DUST EXTRACTOR

Abstract

A dust extractor (1) includes: a head (2) having a top cover (13); a tank (3) disposed below the head and on which a first electrically conductive member (41) is mounted; a tank cover (4) disposed between the head and the tank and having a cover part (16) covering an opening (3F) in an upper-end portion of the tank and a suction tube (17) into which a dust-extracting hose (6) is insertable, and on which a second electrically conductive member (42) is mounted; and a suction unit (7) that includes a motor (24) and a blower fan (25) that is rotated by a rotational force generated by the motor, and that generates a suction force in the suction tube. The first electrically conductive member is grounded. The second electrically conductive member is electrically connected to the first electrically conductive member.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese patent application no. 2023-212702 filed on Dec. 18, 2023, the contents of which are fully incorporated herein by reference.

TECHNICAL FIELD

Techniques disclosed in the present specification relate to a dust extractor.

BACKGROUND ART

Japanese Laid-open Patent Publication 2013-202327 discloses an electric dust extractor that comprises a ground plate and a cable for discharging, to ground, static electricity that has accumulated in a hose joint.

SUMMARY OF THE INVENTION

In Japanese Laid-open Patent Publication 2013-202327, because the hose joint is provided on a tank, static electricity may accumulate on structural members other than the tank.

It is one non-limiting object of the present teachings to disclose techniques disclosed for discharging static electricity that has accumulated on a dust extractor.

In one non-limiting aspect of the present teachings, a dust extractor may comprise: a head having a top cover; a tank which is disposed more downward than (below) the head and on which a first electrically conductive member is mounted; a tank cover which is disposed between the head and the tank and has a cover part covering an opening in an upper-end portion of the tank and a suction tube into which a dust-extracting hose is inserted, and on which a second electrically conductive member is mounted; and a suction unit that includes a motor and a blower fan rotated by a rotational force generated by the motor, and that generates a suction force in the suction tube. The first electrically conductive member may be grounded. The second electrically conductive member may be connected to the first electrically conductive member.

According to one or more techniques disclosed in the present specification, static electricity that has accumulated on or in a dust extractor can be safely discharged without causing discomfort to (i.e. “shocking”) the user.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an oblique view, viewed from the upper-left front, that shows a dust extractor according to an embodiment of the present teachings.

FIG. 2 is an oblique view, viewed from the lower-right front, that shows the dust extractor according to the embodiment.

FIG. 3 is a cross-sectional view that shows the dust extractor according to the embodiment.

FIG. 4 is an exploded, oblique view that shows a tank and a tank cover according to the embodiment.

FIG. 5 is an oblique view, viewed from the upper-left front, that shows a suction tube according to the embodiment.

FIG. 6 is an oblique view, viewed from the upper-right front, that shows the suction tube according to the embodiment.

FIG. 7 is an oblique view, viewed from the upper-right front, that shows the suction tube according to the embodiment.

FIG. 8 is an exploded, oblique, cross-sectional view, viewed from the upper-right front, that shows the tank and the tank cover according to the embodiment.

FIG. 9 is an oblique, cross-sectional view, viewed from the upper-right front, that shows the tank according to the embodiment.

FIG. 10 is a cross-sectional view that shows a portion of the tank according to the embodiment.

FIG. 11 is a cross-sectional view that shows a portion of the tank and a portion of the tank cover according to the embodiment.

FIG. 12 is an oblique, cross-sectional view, viewed from the upper-right front, that shows a portion of the tank and a portion of the tank cover according to the embodiment.

FIG. 13 is an oblique, cross-sectional view, viewed from the upper-right front, that shows a portion of the tank and a portion of the tank cover according to the embodiment.

DETAILED DESCRIPTION OF THE INVENTION

As was noted above, the dust extractor may comprise: a head having a top cover; a tank which is disposed more downward than the head and on which a first electrically conductive member is mounted; a tank cover which is disposed between the head and the tank and has a cover part covering an opening in an upper-end portion of the tank and a suction tube into which a dust-extracting hose is inserted, and on which a second electrically conductive member is mounted; and a suction unit that includes a motor and a blower fan rotated by a rotational force generated by the motor, and that generates a suction force in the suction tube. The first electrically conductive member may be grounded or configured to contact a grounding surface, such as a floor on which the dust extractor is movable during a vacuuming operation. The second electrically conductive member may be electrically connected to the first electrically conductive member.

In the above-mentioned configuration, static electricity that has accumulated on the tank cover is discharged to ground via the second electrically conductive member and the first electrically conductive member. Therefore, discomfort (e.g., an electrical shock or discharge) felt by a user of the dust extractor, which may be caused by static electricity that accumulates on the dust extractor, is curtailed.

In one or more embodiments, at least a portion of the second electrically conductive member may be disposed in the interior of the suction tube so as to contact the dust-extracting hose.

In the above-mentioned configuration, static electricity that has accumulated on the dust-extracting hose can be safely discharged to ground via the second electrically conductive member and the first electrically conductive member. Discomfort felt by a user of the dust extractor, which may be caused by static electricity that accumulates on the dust extracting hose, is curtailed.

In one or more embodiments, the second electrically conductive member may be an elastic member, such as a spring or a bow that returns to an original shape after having been compressed.

In the above-mentioned configuration, because the second electrically conductive member is pressed against the first electrically conductive member owing to the elastic force of the second electrically conductive member, the second electrically conductive member and the first electrically conductive member can stably (reliably) maintain electrical continuity (an electrical connection).

In one or more embodiments, the second electrically conductive member may include a leaf spring.

In the above-mentioned configuration, because the second electrically conductive member is plate-shaped, the second electrically conductive member and the first electrically conductive member can stably maintain electrical continuity.

In one or more embodiments, the first electrically conductive member may include a lead line (e.g., a wire, such as an insulated wire or cable having a conductor core (e.g., a metal core, such as a copper wire), and an insulation layer (e.g., an electrically insulating material, such as a plastic) surrounding the conductor core).

In the above-mentioned configuration, because the first electrically conductive member can be folded into a wide variety of arbitrary shapes, it can be disposed at an arbitrary location within the tank.

In one or more embodiments, the dust extractor may further comprise a connector mounted on an end portion of the lead line, and a screw that, when connected to the connector, fixes the connector to the tank. The second electrically conductive member may (electrically) contact the screw.

In the above-mentioned configuration, the second electrically conductive member can maintain electrical continuity (an electrical connection) with the first electrically conductive member via the screw and the connector. The second electrically conductive member can stably (reliably) establish electrical continuity (an electrical connection) with a head portion of the screw.

In one or more embodiments, the dust extractor may further comprise a screw that, when connected to the first electrically conductive member, fixes the first electrically conductive member to the tank. A portion (e.g., an end portion) of the second electrically conductive member may contact the screw.

In the above-mentioned configuration, the second electrically conductive member can maintain electrical continuity (an electrical connection) with the first electrically conductive member via the screw. The second electrically conductive member can stably (reliably) establish electrical continuity (an electrical connection) with a head portion of the screw.

In one or more embodiments, a screw boss may be provided on an inner surface of the tank. The screw may fix the first electrically conductive member to the screw boss.

In the above-mentioned configuration, because the screw boss is provided on the inner surface of the tank, the screw and the first electrically conductive member are stably (securely) fixed to the tank.

In one or more embodiments, an upper-end portion of the second electrically conductive member may be disposed to face a passageway of the suction tube. A lower-end portion of the second electrically conductive member may be disposed more downward than the lower surface of the cover part. An intermediate portion of the second electrically conductive member between the upper-end portion and the lower-end portion may be fixed to at least a portion of the tank cover.

In the above-mentioned configuration, the second electrically conductive member, when fixed to the tank cover, can reliably maintain electrical continuity (an electrical connection) with the dust-extracting hose that has been inserted in the suction tube and the first electrically conductive member of the tank.

In one or more embodiments, the intermediate portion of the second electrically conductive member may be at least partially embedded in the interior of the tank cover; i.e. the intermediate portion of the second electrically conductive member and the tank cover may be formed in an integral (inseparable) manner, wherein a portion of the tank cover extends through the intermediate portion.

In the above-mentioned configuration, the second electrically conductive member is stably (securely) fixed to the tank cover.

In one or more embodiments, a hole may be provided in the intermediate portion. At least a portion of the tank cover may penetrate into the hole; i.e. a portion of the tank cover extends through the hole in the intermediate portion.

In the above-mentioned configuration, the second electrically conductive member is stably (securely) fixed to the tank cover.

In one or more embodiments, a ring portion may be provided on an inner surface of the suction tube. An upper-end portion of the second electrically conductive member is disposed in (inserted into) a notched portion provided (defined) in a portion of the ring portion.

In the above-mentioned configuration, by disposing (inserting) the upper-end portion of the second electrically conductive member in the notched portion, the upper-end portion of the second electrically conductive member is positioned in the suction tube.

In one or more embodiments, the first electrically conductive member may be supported on (fixed to) the inner surface of the tank.

In the above-mentioned configuration, because the first electrically conductive member does not move unnecessarily (in an undesirable manner) within the interior space of the tank, deterioration of the first electrically conductive member caused by frictional rubbing of an outer surface of the first electrically conductive member against another surface can be avoided or at least minimized.

In one or more embodiments, the dust extractor may further comprise an (at least one) intermediate holding member that is provided on (affixed to) the inner surface of the tank and holds the first electrically conductive member.

In the above-mentioned configuration, because the first electrically conductive member is held by the intermediate holding member, unnecessary (undesirable) movement of the first electrically conductive member in the interior space of the tank is curtailed. Because the first electrically conductive member does not move unnecessarily in the interior space of the tank, deterioration of the first electrically conductive member caused by frictional rubbing of an outer surface of the first electrically conductive member against another surface can be avoided or at least minimized.

In one or more embodiments, the intermediate holding member includes a first protruding part protruding from the inner surface of the tank, and a second protruding part adjacent to the first protruding part. The first electrically conductive member may be inserted between the first protruding part and the second protruding part and thereby held by the intermediate holding member.

In the above-mentioned configuration, the intermediate holding member can hold the first electrically conductive member with a simple structure.

In one or more embodiments, the dust extractor may further comprise a lower-end holding member that is inserted into an opening provided in (and/or on) a bottom portion of the tank. At least a portion of the first electrically conductive member may be held by the lower-end holding member. A lower-end portion of the first electrically conductive member may be disposed more downward than (below) a lower surface of the tank; i.e. the lower-end portion of the first electrically conductive member is preferably configured to extend below the lower surface of the tank so that the lower-end portion of the first electrically conductive member is positioned to contact a grounding surface, such as the floor, while the dust extractor is being used.

In the above-mentioned configuration, the lower-end portion of the first electrically conductive member is positioned by the lower-end holding member. Because the amount of protrusion of the lower-end portion of the first electrically conductive member from the lower surface of the tank is maintained at a constant value, the lower-end portion of the first electrically conductive member can be stably (reliably) grounded. In addition, because the lower-end holding member also may function as a sealing member that closes up the opening of the bottom portion, dust or liquid housed in the interior space of the tank is less likely to leak through the opening of the bottom portion.

Embodiments according to the present disclosure are explained below, with reference to the drawings, but the present disclosure is not limited to the embodiments. The structural elements of the embodiments explained below can be combined as appropriate. In addition, there are also situations in which some of the structural elements are not used.

In the embodiments, positional relationships among parts will be explained using the terms “front,” “rear,” “left,” “right,” “up,” and “down.” Each of these terms indicates a relative position or a direction, using the center of a dust extractor 1 as a reference.

Dust Extractor

FIG. 1 is an oblique view, viewed from the upper-left front, that shows the dust extractor 1 according to one non-limiting embodiment of the present teachings. FIG. 2 is an oblique view, viewed from the lower-right front, that shows the dust extractor 1 according to the embodiment. FIG. 3 is a cross-sectional view that shows the dust extractor 1 according to the embodiment.

In the embodiment, the dust extractor 1 is a wet/dry dust extractor that can suction not only gas, but liquid as well. Air is given as an example of a gas. Water is given as an example of a liquid. Of course, the dust extract 1 can also suction (vacuum) dust, debris, etc.

As shown in FIGS. 1-3, the dust extractor 1 comprises a head 2, a tank 3, a tank cover 4, a latch 5, a dust-extracting hose 6, a suction unit 7, a filter unit 8, a float 9, a battery-mounting part 10, a controller 11, and an operation panel 12.

The tank 3 houses all material that is suctioned into the dust extractor 1, such as debris, dust, liquid, etc. The tank 3 is disposed more downward than (below) the head 2. At least a portion of the tank 3 is disposed more downward than (below) the tank cover 4. At least a portion of the tank cover 4 is disposed more downward than (below) the head 2. The tank cover 4 is disposed between the head 2 and the tank 3. The head 2 and the tank cover 4 are each detachable from the tank 3. The latch 5 fixes the head 2 and the tank 3. The tank cover 4 is sandwiched between the head 2 and the tank 3.

The head 2 comprises a top cover 13, a battery cover 14, and a handle 15.

The top cover 13 is disposed more upward than (above) the tank cover 4. The top cover 13 is disposed to cover the tank cover 4 from above. The top cover 13 is made of a synthetic resin (polymer). The top cover 13 forms a housing space between itself and the tank cover 4. The controller 11 and the suction unit 7 are each disposed in the housing space between the top cover 13 and the tank cover 4. The operation panel 12 is disposed in an opening 13A provided in a front portion of the top cover 13. The battery-mounting part 10 is disposed in the interior of a recessed portion 13B provided in an upper portion of the top cover 13.

The battery cover 14 covers the recessed portion 13B. The battery cover 14 is supported on the top cover 13 in a pivotable manner. The battery cover 14 changes, by pivoting, between a closed state in which the recessed portion 13B is closed and an open state in which the recessed portion 13B is open.

The handle 15 is configured to be gripped by a user of the dust extractor 1. The handle 15 is coupled to the top cover 13 in a pivotable manner. The user can transport (carry) the dust extractor 1 by gripping the handle 15.

FIG. 4 is an exploded, oblique view that shows the tank 3 and the tank cover 4 according to the embodiment. The tank 3 has an interior space that houses debris, dust, liquid, etc. The tank 3 comprises a front portion 3A, a rear portion 3B, a left portion 3C, a right portion 3D, and a bottom portion 3E. An opening 3F is provided in an upper-end portion of the tank 3. The dimension of the tank 3 in the front-rear direction is larger than the dimension of the tank 3 in the left-right direction. The tank 3 is preferably made of a synthetic resin (polymer).

A hose-winding portion 3G is provided on the front portion 3A of the tank 3. The hose-winding portion 3G is provided so as to protrude forward from the front portion 3A. A recessed portion 3H is provided in each of the left portion 3C and the right portion 3D of the tank 3.

As shown in FIG. 2, the tank 3 has four leg portions (legs) 3J. The leg portions 3J are protruding portions (protrusions) provided on the bottom portion 3E. The leg portions 3J are provided so as to protrude downward from a lower surface of the bottom portion 3E. One leg portion 3J is provided on each of the four corners of the lower surface of the bottom portion 3E.

The tank 3 has a projection portion 3K provided at a portion of the upper-end portion of the tank 3. The projection portion 3K is provided at a front portion and a left portion of the upper-end portion of the tank 3. The projection portion 3K is disposed to cover a portion of the opening 3F. A hole 3L is formed in the projection portion 3K. The hole 3L is formed to pass through an upper surface and a lower surface of the projection portion 3K.

The tank cover 4 is mounted on the upper-end portion of the tank 3. The tank cover 4 comprises: a plate-shaped cover part 16 covering the opening 3F of the upper-end portion of the tank 3; and a suction tube 17, into which the dust-extracting hose 6 is inserted. The tank cover 4 is preferably made of a synthetic resin (polymer). A sealing member 18 is disposed on a perimeter-edge portion of a lower surface of the cover part 16. The sealing member 18 seals the boundary between the tank 3 and the tank cover 4. In a state in which the tank cover 4 is mounted on the upper-end portion of the tank 3, the sealing member 18 contacts both the lower surface of the cover part 16 and an upper-end surface of the tank 3. The sealing member 18 is preferably made of an elastomer, such as a rubber.

FIG. 5 is an oblique view, viewed from the upper-left front, that shows the suction tube 17 according to the embodiment. FIG. 6 is an oblique view, viewed from the upper-right front, that shows the suction tube 17 according to the embodiment. The suction tube 17 is configured to suction and transport into the tank 3 at least one of debris, dust and liquid. As shown in FIG. 1, the suction tube 17 is covered by the top cover 13. The suction tube 17 is disposed upward of the projection portion 3K. The suction tube 17 has an inlet port 19 and a passageway 20 connected to the inlet port 19. The inlet port 19 is disposed at a front-end portion of the suction tube 17. The inlet port 19 of the suction tube 17 faces forward. The inlet port 19 passes through the passageway 20 to the hole 3L.

The suction tube 17 is connected to the dust-extracting hose 6. The dust-extracting hose 6 is inserted into the interior of the suction tube 17 through the inlet port 19. The dust-extracting hose 6 comprises a joint part 21. The joint part 21 comprises a protruding portion. The suction tube 17 has a groove 22. The protruding portion of the joint part 21 mates with the groove 22.

The dust-extracting hose 6 is windable around the hose-winding portion 3G for storage purposes. A left surface, a right surface, and a lower surface of the hose-winding portion 3G are each a curved surface matched to an outer-circumferential surface of the dust-extracting hose 6. A hook 23 is provided on an upper surface of the hose-winding portion 3G. The hook 23 holds at least a portion of the dust-extracting hose 6.

The dust-extracting hose 6, which is connected to the suction tube 17, is supported on a front portion of the tank 3 by being wound around the hose-winding portion 3G and held by the hook 23.

The suction unit 7, the filter unit 8, the battery-mounting part 10, and the controller 11 are each supported on the tank cover 4. The suction unit 7, the battery-mounting part 10, and the controller 11 are each disposed more upward than (above) an upper surface of the cover part 16 of the tank cover 4. The filter unit 8 is disposed more downward than (below) a lower surface of the tank cover 4.

The suction unit 7, the battery-mounting part 10, and the controller 11 are arranged in this order in the front-rear direction. The suction unit 7 is disposed on a rear portion of the tank cover 4. The battery-mounting part 10 is disposed more forward than (in front of) the suction unit 7. The controller 11 is disposed more forward than (in front of) the battery-mounting part 10.

The suction unit 7 generates a suction force in the inlet port 19 of the suction tube 17. As shown in FIG. 3, the suction unit 7 comprises a motor 24, a blower fan 25, a motor-housing part 26, and a fan-housing part 27.

The motor 24 generates a rotational force for rotating the blower fan 25. The motor 24 is an inner-rotor-type brushless motor. The motor 24 comprises a stator, a rotor disposed in the interior of the stator, and a rotor shaft fixed to the rotor. A lower portion of the rotor shaft protrudes downward from a lower-end surface of the rotor.

The blower fan 25 is rotated by the rotational force generated by the motor 24. The blower fan 25 is fixed to the lower portion of the rotor shaft. The motor 24 is driven to rotate the rotor shaft, and the blower fan 25 rotates thereby.

The motor-housing part 26 houses the motor 24. The fan-housing part 27 houses the blower fan 25. The motor-housing part 26 is disposed more upward than (above) the fan-housing part 27.

The blower fan 25 generates a suction force in an air-intake port 28 provided in a lower portion of the fan-housing part 27. The interior space of the tank 3 is connected to the inlet port 19 through the hole 3L. The air-intake port 28 is connected to the inlet port 19 via the filter unit 8, the interior space of the tank 3, and the hole 3L. Rotation of the blower fan 25 generates a suction force in the inlet port 19 via the air-intake port 28, the filter unit 8, the interior space of the tank 3, and the hole 3L. Air suctioned in from the inlet port 19 passes through the hole 3L, the interior space of the tank 3, and the filter unit 8, and subsequently flows into the air-intake port 28 of the suction unit 7. Dust, debris, liquid, etc. suctioned in from the inlet port 19 is housed (stored) in the interior space of the tank 3.

The tank cover 4 has a turning (curved) path 32 and an exhaust path 33. Air that has flowed into the interior space of the fan-housing part 27 via the air-intake port 28 passes through the turning path 32 and is subsequently exhausted from the exhaust path 33.

The filter unit 8 traps solid materials, such as e.g., debris, dust, etc., from the air flowing into the air-intake port 28 of the suction unit 7. The filter unit 8 is disposed in the interior space of the tank 3 and is supported by the tank cover 4. The filter unit 8 has a tubular shape having a bottom portion. The filter unit 8 is supported by the tank cover 4 so that the interior space of the filter unit 8 and the air-intake port 28 are fluidly connected. The float 9 is disposed in the interior space of the filter unit 8.

The battery-mounting part 10 is connected to a battery pack 29. The battery pack 29 is mounted on the battery-mounting part 10. The battery-mounting part 10 has a pair of guide rails and a terminal block disposed between the pair of guide rails. The guide rails extend in the left-right direction. The guide rails are disposed spaced apart in the front-rear direction.

The battery pack 29 is detachable from the battery-mounting part 10. When mounted on the battery-mounting part 10, the battery pack 29 supplies electric power to the motor 24. In addition, the battery pack 29 supplies electric power to electronic devices installed in the dust extractor 1. The battery pack 29 may be a general-purpose rechargeable battery pack (or battery cartridge) that is configured to be used as an electric-power supply for various electrical devices. For example, the battery pack 29 can be used as an electric-power supply for a power tool and/or can be used as an electric-power supply for an electrical device other than a power tool. The battery pack 29 can be used as an electric-power supply for a dust extractor other than the dust extractor 1 according to the embodiment. The battery pack 29 comprises at least one lithium-ion battery, typically several electrically connected lithium-ion battery cells, although a variety of battery chemistries, including solid-state batteries, may be utilized with the present teachings. The battery pack 29 is preferably a rechargeable battery. The battery-mounting part 10 has a structure equivalent to that of a battery-mounting part of a power tool.

The user of the dust extractor 1 can mount the battery pack 29 on the battery-mounting part 10 and remove the battery pack 29 from the battery-mounting part 10. The user can mount the battery pack 29 on the battery-mounting part 10, e.g., by inserting the battery pack 29 into the battery-mounting part 10 from the right. The battery pack 29 is inserted into the battery-mounting part 10 while being guided by the guide rails. By mounting the battery pack 29 on the battery-mounting part 10, the terminals of the battery pack 29 and the terminal block of the battery-mounting part 10 become electrically connected. The user of the dust extractor 1 can remove the battery pack 29 from the battery-mounting part 10 by moving the battery pack 29 leftward.

The controller 11 controls (the energization or driving of) the motor 24. The controller 11 comprises a control circuit board and a case, which holds the control circuit board. The control circuit board comprises a microcomputer (e.g., one or more microprocessors, memory/storage, I/O devices, etc.) and switching devices (e.g., power FETs) for controlling (supplying drive currents to) the motor 24.

The operation panel 12 is disposed on a front surface of the top cover 13. The operation panel 12 comprises a manipulatable dial 12A and a display part 12B. The manipulatable dial 12A is manually rotatable. The display part 12B displays the remaining charge of the battery pack 29. When the user manipulates (rotates) the manipulatable dial 12A, a manipulation signal is generated. The manipulation signal is transmitted to the controller 11. The controller 11 switches between driving and stopping the motor 24 based on the manipulation signal. In addition, the controller 11 adjusts the rotational speed of the motor 24 based on the manipulation signal. By adjusting the rotational speed of the motor 24, the suction force generated in the inlet port 19 is adjusted. When the rotational speed of the motor 24 becomes high, the suction force generated in the inlet port 19 becomes high; and when the rotational speed of the motor 24 becomes low, the suction force generated in the inlet port 19 becomes low. In the embodiment, by manipulating (rotating) the manipulatable dial 12A, the state of the motor 24 is switched between a stopped state, a low-suction-force state, and a high-suction-force state.

It is noted that the top cover 13 has a receptacle 31, into which a suction nozzle 30 is inserted, as shown in FIG. 2. The receptacle 31 is provided in a right-rear portion of the top cover 13.

Operation

To perform cleaning using the dust extractor 1, the user manipulates (rotates) the manipulatable dial 12A to drive the motor 24. When the motor 24 is driven, the blower fan 25 rotates. When the blower fan 25 rotates, a suction force is generated in the inlet port 19.

When dry cleaning is performed (i.e. liquid is not being suctioned), air is suctioned into the inlet port 19 through the dust-extracting hose 6. The air suctioned into the inlet port 19 flows into the interior space of the tank 3 via the suction tube 17 and the hole 3L. At least a portion of the air that flowed into the interior space of the tank 3 passes through the filter unit 8 and into the interior space of the filter unit 8. The dust contained in the air is trapped by the filter unit 8. The air that flowed into the interior space of the filter unit 8 flows into the interior space of the fan-housing part 27 via the air-intake port 28. The air, which flowed into the interior space of the fan-housing part 27 via the air-intake port 28, passes through the turning path 32 provided in the tank cover 4 and is subsequently exhausted from the exhaust path 33.

When wet cleaning is performed, liquid is suctioned into the inlet port 19 through the dust-extracting hose 6. The liquid suctioned into the inlet port 19 flows into the interior space of the tank 3 via the suction tube 17 and the hole 3L. At least a portion of the liquid that flowed into the interior space of the tank 3 is stored in the tank 3. At least a portion of the liquid that flowed into the interior space of the tank 3 passes through the filter unit 8 and flows into the interior space of the filter unit 8. The float 9 is disposed in the interior space of the filter unit 8. The float 9 can float in the liquid. When the liquid flows into the interior space of the filter unit 8, the float 9 moves upward to close up the air-intake port 28 of the suction unit 7. When the float 9 has moved up to the air-intake port 28 of the suction unit 7 and closed up (blocked) the air-intake port 28, the flow of liquid into the interior space of the fan-housing part 27 and the interior space of the motor-housing part 26 is inhibited (blocked, stopped). Penetration of liquid into the motor 24 is thereby inhibited.

Grounded Structure

FIG. 7 is an oblique view, viewed from the upper-right front, that shows the suction tube 17 according to the embodiment. FIG. 8 is an exploded, oblique, cross-sectional view, viewed from the upper-right front, that shows the tank 3 and the tank cover 4 according to the embodiment. FIG. 9 is an oblique, cross-sectional view, viewed from the upper-right front, that shows the tank 3 according to the embodiment. FIG. 10 is a cross-sectional view that shows a portion of the tank 3 according to the embodiment. FIG. 11 is a cross-sectional view that shows a portion of the tank 3 and a portion of the tank cover 4 according to the embodiment. FIG. 12 is an oblique, cross-sectional view, viewed from the upper-right front, that shows a portion of the tank 3 and a portion of the tank cover 4 according to the embodiment. FIG. 13 is an oblique, cross-sectional view, viewed from the upper-right front, that shows a portion of the tank 3 and a portion of the tank cover 4 according to the embodiment. FIG. 13 corresponds to a partial, enlarged view of FIG. 12.

The dust extractor 1 has a grounded structure (electrical grounding structure) 40 that discharges static electricity that accumulates on and/or in at least a portion of the dust extractor 1. The grounded structure 40 has a first electrically conductive member 41 mounted on and/or in the tank 3 and a second electrically conductive member 42 mounted on the tank cover 4. The first electrically conductive member 41 is grounded. The second electrically conductive member 42 is electrically connected to the first electrically conductive member 41. Static electricity that has accumulated on the tank cover 4 is discharged to ground via the second electrically conductive member 42 and the first electrically conductive member 41.

At least a portion of the second electrically conductive member 42 is disposed in the interior of the suction tube 17 so as to contact the dust-extracting hose 6, when it is inserted into the interior of the suction tube 17. At least a portion of the second electrically conductive member 42 is disposed to face the passageway 20 of the suction tube 17.

The second electrically conductive member 42 is an elastic member. In the embodiment, the second electrically conductive member 42 includes a leaf spring. The second electrically conductive member 42 is a metal leaf spring that is elongated in the up-down direction. However, the second electrically conductive member 42 may have a variety of forms or shapes that enable it to be resiliently biased into electrical contact with the dust-extracting hose 6 when the dust-extracting hose 6 is inserted into the suction tube 17, such as bow-shaped, angular-shaped (e.g., rounded triangular shaped), coil spring shaped, garter spring shaped, cantilever shaped, etc..

An upper-end portion 42B of the second electrically conductive member 42 is disposed to face the passageway 20 of the suction tube 17. A lower-end portion 42C of the second electrically conductive member 42 is disposed more downward than (below) the lower surface of the cover part 16. An intermediate portion 42A of the second electrically conductive member 42 between the upper-end portion 42B and the lower-end portion 42C is fixed to at least a portion of the tank cover 4.

The upper-end portion 42B of the second electrically conductive member 42 contacts (electrically connects to) the dust-extracting hose 6 that has been inserted into the interior of the suction tube 17. The second electrically conductive member 42 generates an elastic force such that the upper-end portion 42B is pressed against the dust-extracting hose 6 that has been inserted into the interior of the suction tube 17. When the dust-extracting hose 6 is inserted into the interior of the suction tube 17, the upper-end portion 42B is in close contact with the dust-extracting hose 6.

Referring back to FIG. 6, a ring portion 17A is provided on an inner surface of the suction tube 17. The ring portion 17A is fixed to the suction tube 17. In the embodiment, the suction tube 17 and the ring portion 17A are integral. An end surface of the dust-extracting hose 6 that has been inserted into the suction tube 17 is connected to the ring portion 17A.

The upper-end portion 42B of the second electrically conductive member 42 is disposed in a notched portion 17B, which is provided in a portion of the ring portion 17A. The notched portion 17B is provided in a left portion of the ring portion 17A. By disposing the upper-end portion 42B in the notched portion 17B, the upper-end portion 42B is positioned in the suction tube 17.

The lower-end portion 42C of the second electrically conductive member 42 is disposed in the interior space of the tank 3. The lower-end portion 42C of the second electrically conductive member 42 is inserted into the hole 3L of the tank 3 from above the tank 3, as can be understood by viewing FIGS. 8, 10 and 11 together. The lower-end portion 42C is disposed in the interior space of the tank 3 via the hole 3L. The lower-end portion 42C of the second electrically conductive member 42 is connected to the first electrically conductive member 41 in the interior space of the tank 3.

As can be seen in FIG. 7, the intermediate portion 42A of the second electrically conductive member 42 is embedded in the interior of the tank cover 4. The intermediate portion 42A is joined/affixed to (integrated or interconnected with) the tank cover 4. In the state in which the intermediate portion 42A is mounted on a base material of the tank cover 4, the intermediate portion 42A is joined to the base material using the same type of synthetic resin (polymer) as the base material of the tank cover 4. For example, the intermediate portion 42A may be at least partially embedded in the wall of the tank cover 4 by joining the intermediate portion 42A with the base material.

The intermediate portion 42A has a plate shape that is elongated in the up-down direction. Holes 42D are provided in the intermediate portion 42A. For example, two of the holes 42D may be provided in the up-down direction. At least a portion of the material (polymer) of the tank cover 4 penetrates into the holes 42D. That is, in the joining process, molten synthetic resin (e.g., a thermoplastic polymer) penetrates into the holes 42D. Because at least a portion of the molten material of the tank cover 4 penetrates into the holes 42D and then solidifies, the intermediate portion 42A is rigidly (securely) fixed to the tank cover 4.

Referring now to FIGS. 8-13, the first electrically conductive member 41 is supported on an inner surface of the tank 3. The first electrically conductive member 41 includes a lead line. The first electrically conductive member 41 has an electrically conductive core wire (e.g., copper or aluminum wire) and an insulative coating film (sheath, wrap) covering the core wire. At each of a lower-end portion 41A and an upper-end portion 41B of the first electrically conductive member 41, the core wire is exposed from the coating film. Along an intermediate portion of the first electrically conductive member 41, the core wire is covered by the coating film.

As can be seen, in particular, in FIGS. 10-13, the upper-end portion 41B of the first electrically conductive member 41 is fixed to the tank 3 by a screw 46. When the screw 46 is connected to the core wire of the first electrically conductive member 41, the screw 46 fixes the upper-end portion 41B of the first electrically conductive member 41 to the tank 3. In the embodiment, a connector 45 is mounted on the upper-end portion 41B of the first electrically conductive member 41. The connector 45 is fixed to the tank 3 by the screw 46. By fixing the connector 45 to the tank 3, the screw 46 fixes the upper-end portion 41B of the first electrically conductive member 41 to the tank 3.

The connector 45 is an electrically conductive plate member. The screw 46 is electrically conductive, preferably made of metal. When the screw 46 is connected to the connector 45, the screw 46 fixes the connector 45 to the tank 3. The screw 46, the connector 45, and the core wire of the first electrically conductive member 41 are in electrical continuity (electrically connected).

A screw boss 3M is provided on the inner surface of the tank 3. The screw boss 3M is provided more upward than (above) a bottom surface of the bottom portion 3E. The screw boss 3M is provided more upward than (above) the center of the tank 3 in the up-down direction. In the embodiment, the screw boss 3M is provided on an upper portion and a front portion of an inner surface (right surface) of the left portion 3C of the tank 3. The screw boss 3M is provided directly below the hole 3L.

The screw 46 fixes the upper-end portion 41B of the first electrically conductive member 41 to the screw boss 3M. By fixing the connector 45 to the screw boss 3M, the screw 46 fixes the upper-end portion 41B of the first electrically conductive member 41 to the screw boss 3M.

The connector 45 has a hole, into which the threaded portion of the screw 46 is inserted (screw-fastened). The screw hole of the screw boss 3M extends downward from an upper-end surface of the screw boss 3M. From above the screw boss 3M, the screw 46 is inserted through the hole in the connector 45 into the screw hole of the screw boss 3M. The connector 45 is disposed between the head portion of the screw 46 and the upper-end surface of the screw boss 3M. By inserting the threaded portion of the screw 46 into the screw hole of the screw boss 3M, the connector 45 is fixed to the screw boss 3M of the tank 3. By fixing the connector 45 to the screw boss 3M of the tank 3, the upper-end portion 41B of the first electrically conductive member 41 is fixed to the screw boss 3M of the tank 3. The head portion of the screw 46 is disposed more upward than (above) the screw boss 3M. The head portion of the screw 46 faces upward. The head portion of the screw 46 is disposed directly below the hole 3L.

The lower-end portion 42C of the second electrically conductive member 42 contacts the head portion of the screw 46. The lower-end portion 42C contacts the head portion of the screw 46 from above the screw 46. The second electrically conductive member 42 generates an elastic force such that the lower-end portion 42C is pressed against the head portion of the screw 46. The lower-end portion 42C is in close contact with the head portion of the screw 46.

Intermediate holding members 44, which hold the first electrically conductive member 41, are provided on the inner surface of the tank 3. The intermediate holding members 44 hold intermediate portions of the first electrically conductive member 41. The intermediate holding members 44 hold the coating film (insulative sheath) of the first electrically conductive member 41. The intermediate holding members 44 hold intermediate portions of the first electrically conductive member 41 so that the first electrically conductive member 41 contacts the inner surface of the tank 3.

The intermediate holding members 44 are provided on the right surface of the left portion 3C and the bottom surface of the bottom portion 3E of the tank 3. The intermediate holding members 44 is provided in a spaced apart relationship. In the embodiment, two of the intermediate holding members 44 are provided in the up-down direction on the right surface of the left portion 3C. Two of the intermediate holding members 44 are provided in the left-right direction on the bottom surface of the bottom portion 3E.

Each intermediate holding member 44 includes a first protruding part 44A, which protrudes from the inner surface of the tank 3, and a second protruding part 44B, which is adjacent to the first protruding part 44A. The intermediate portion of the first electrically conductive member 41 is inserted between the first protruding parts 44A and the second protruding parts 44B. By inserting the first electrically conductive member 41 between the first protruding parts 44A and the second protruding parts 44B, the intermediate holding members 44 can hold the first electrically conductive member 41.

The intermediate holding members 44 are formed from an insulative material. The intermediate holding members 44 are formed, for example, from a synthetic resin (an electrically insulating polymer). The intermediate holding members 44 are fixed to the inner surface of the tank 3. In the embodiment, the tank 3 and the intermediate holding members 44 are integral.

A lower-end holding member 43 is disposed on and/or in the bottom portion 3E of the tank 3. An opening is provided in a center portion of the bottom portion 3E of the tank 3. The lower-end holding member 43 is inserted into the opening provided in the bottom portion 3E of the tank 3. The lower-end holding member 43 functions as a sealing member that closes up the opening of the bottom portion 3E. At least a portion of the first electrically conductive member 41 is held by the lower-end holding member 43. The lower-end holding member 43 holds the lower-end portion 41A of the first electrically conductive member 41. The lower-end holding member 43 is formed from an insulative material. The lower-end holding member 43 is formed, for example, from a synthetic resin (polymer).

The lower-end holding member 43 has a hole, into which the lower-end portion 41A of the first electrically conductive member 41 is inserted. The lower-end holding member 43 closes up the opening provided in the bottom portion 3E. The lower-end portion 41A of the first electrically conductive member 41 protrudes more downward than (below) a lower surface of the lower-end holding member 43. The lower-end portion 41A of the first electrically conductive member 41 is disposed more downward than (below) the lower surface of the tank 3. In the state in which the leg portions 3J of the tank 3 are placed on the ground (e.g., a floor), the lower-end portion 41A of the first electrically conductive member 41 contacts the ground. That is, when the leg portions 3J of the tank 3 are placed on the ground, the lower-end portion 41A of the first electrically conductive member 41 is grounded.

The upper-end portion 41B of the first electrically conductive member 41 is fixed to the screw boss 3M by the screw 46. The lower-end portion 41A of the first electrically conductive member 41 is held by the lower-end holding member 43 and disposed more downward than the lower surface of the tank 3. Intermediate portions of the first electrically conductive member 41 are held by the plurality of intermediate holding members 44. The first electrically conductive member 41 is disposed along the right surface of the left portion 3C and the bottom surface of the bottom portion 3E.

It is possible that static electricity will accumulate on the dust-extracting hose 6. The dust-extracting hose 6, which has been inserted in the suction tube 17, and the upper-end portion 42B of the second electrically conductive member 42 are in electrical contact with each other. The lower-end portion 42C of the second electrically conductive member 42 and the screw 46 are in contact with each other. The screw 46 is in electrical continuity with the upper-end portion 41B of the first electrically conductive member 41 via the connector 45. The lower-end portion 41A of the first electrically conductive member 41 is grounded. Consequently, static electricity accumulated on the dust-extracting hose 6 is discharged to ground via the second electrically conductive member 42 and the first electrically conductive member 41. Because static electricity accumulation on the dust-extracting hose 6 is curtailed by the grounded structure 40, discomfort felt by the user of the dust extractor 1, which may be caused by static electricity that accumulates on the dust-extracting hose 6, is curtailed.

Effects

In the embodiment, as explained above, the dust extractor 1 comprises: the head 2 having the top cover 13; the tank 3, which is disposed more downward than the head 2 and on which the first electrically conductive member 41 is mounted; the tank cover 4, which is disposed between the head 2 and the tank 3 and has the cover part 16 covering the opening 3F in the upper-end portion of the tank 3 and the suction tube 17 into which the dust-extracting hose 6 is inserted, and on which the second electrically conductive member 42 is mounted; and the suction unit 7 that comprises the motor 24 and the blower fan 25, which is rotated by the rotational force generated by the motor 24, and that generates a suction force in the suction tube 17. The first electrically conductive member 41 is grounded when it is in contact with a grounding material, such as a floor. The second electrically conductive member 42 is electrically connected to the first electrically conductive member 41.

In the above-mentioned configuration, static electricity that has accumulated in the tank cover 4 is discharged to ground via the second electrically conductive member 42 and the first electrically conductive member 41. Therefore, discomfort felt by the user of the dust extractor 1, which may be caused by static electricity accumulating on the dust extractor 1, is curtailed.

In the embodiment, at least a portion of the second electrically conductive member 42 is disposed in the interior of the suction tube 17 so as to contact the dust-extracting hose 6.

In the above-mentioned configuration, static electricity that has accumulated on the dust-extracting hose 6 can be safely discharged to ground via the second electrically conductive member 42 and the first electrically conductive member 41. Discomfort felt by the user of the dust extractor 1, which may be caused by static electricity that accumulates on the dust-extracting hose 6, is curtailed.

In the embodiment, the second electrically conductive member 42 is an elastic member.

In the above-mentioned configuration, because the second electrically conductive member 42 is pressed against the first electrically conductive member 41 by the elastic force of the second electrically conductive member 42, the second electrically conductive member 42 and the first electrically conductive member 41 can stably maintain electrical continuity.

In the embodiment, the second electrically conductive member 42 includes a leaf spring.

In the above-mentioned configuration, because the second electrically conductive member 42 is plate-shaped, the second electrically conductive member 42 and the first electrically conductive member 41 can stably maintain electrical continuity.

In the embodiment, the first electrically conductive member 41 includes a lead line.

In the above-mentioned configuration, because the first electrically conductive member 41 can be folded into a wide variety of arbitrary shapes, it can be disposed at an arbitrary location within the tank 3.

In the embodiment, the dust extractor 1 also comprises: the connector 45 mounted on an end portion of the lead line; and the screw 46 that, when connected to the connector 45, fixes the connector 45 to the tank 3. The second electrically conductive member 42 contacts the screw 46.

In the above-mentioned configuration, the second electrically conductive member 42 can maintain electrical continuity with the first electrically conductive member 41 via the screw 46 and the connector 45. The second electrically conductive member 42 can stably maintain electrical continuity with the head portion of the screw 46.

In the embodiment, the screw boss 3M is provided on the inner surface of the tank 3. The screw 46 fixes the first electrically conductive member 41 to the screw boss 3M.

In the above-mentioned configuration, because the screw boss 3M is provided on the inner surface of the tank 3, the screw 46 and the first electrically conductive member 41 are stably fixed to the tank 3.

In the embodiment, the upper-end portion 42B of the second electrically conductive member 42 is disposed to face the passageway 20 of the suction tube 17. The lower-end portion 42C of the second electrically conductive member 42 is disposed more downward than the lower surface of the cover part 16. The intermediate portion 42A of the second electrically conductive member 42 between the upper-end portion 42B and the lower-end portion 42C is fixed to at least a portion of the tank cover 4.

In the above-mentioned configuration, the second electrically conductive member 42, when fixed to the tank cover 4, can maintain electrical continuity between the dust-extracting hose 6 inserted in the suction tube 17 and the first electrically conductive member 41 of the tank 3.

In the embodiment, the intermediate portion 42A is at least partially embedded in the wall of the tank cover 4.

In the above-mentioned configuration, the second electrically conductive member 42 is stably fixed to the tank cover 4.

In the embodiment, the holes 42D are provided in the intermediate portion 42A. At least a portion of the tank cover 4 penetrates into (extends through) the holes 42D.

In the above-mentioned configuration, the second electrically conductive member 42 is stably fixed to the tank cover 4.

In the embodiment, the ring portion 17A is provided on the inner surface of the suction tube 17. The upper-end portion 42B of the second electrically conductive member 42 is disposed in a notched portion 17B provided in a portion of the ring portion 17A.

In the above-mentioned configuration, the upper-end portion 42B of the second electrically conductive member 42 is positioned in the suction tube 17 by being disposed in the notched portion 17B.

In the embodiment, the first electrically conductive member 41 is supported by the inner surface of the tank 3.

In the above-mentioned configuration, because the first electrically conductive member 41 does not move unnecessarily in the interior space of the tank 3, deterioration of the first electrically conductive member 41 is curtailed.

In the embodiment, the dust extractor 1 also comprises the intermediate holding members 44 that are provided on the inner surface of the tank 3 and hold the first electrically conductive member 41.

In the above-mentioned configuration, because the first electrically conductive member 41 is held by the intermediate holding members 44, unnecessary movement of the first electrically conductive member 41 in the interior space of the tank 3 is curtailed. Because the first electrically conductive member 41 does not move unnecessarily in the interior space of the tank 3, deterioration of the first electrically conductive member 41 is curtailed.

In the embodiment, the intermediate holding members 44 comprise the first protruding parts 44A protruding from the inner surface of the tank 3, and the second protruding parts 44B adjacent to the first protruding parts 44A. The first electrically conductive member 41 is inserted between the first protruding parts 44A and the second protruding parts 44B.

In the above-mentioned configuration, the intermediate holding members 44 can hold the first electrically conductive member 41 with a simple structure.

In the embodiment, the dust extractor 1 also comprises the lower-end holding member 43 that is inserted into the opening provided in the bottom portion 3E of the tank 3. At least a portion of the first electrically conductive member 41 is held by the lower-end holding member 43. The lower-end portion 41A of the first electrically conductive member 41 is disposed more downward than (below) the lower surface of the tank 3.

In the above-mentioned configuration, the lower-end portion 41A of the first electrically conductive member 41 is positioned by the lower-end holding member 43. Because the amount of protrusion of the lower-end portion 41A of the first electrically conductive member 41 from the lower surface of the tank 3 is maintained at a constant value, the lower-end portion 41A of the first electrically conductive member 41 can be stably grounded. In addition, because the lower-end holding member 43 also function as a sealing member that closes up the opening of the bottom portion 3E, leakage of dust or liquid housed in the interior space of the tank 3 through the opening of the bottom portion 3E is curtailed.

Other Embodiment

In the embodiment described above, it is assumed that the connector 45 is mounted on the upper-end portion 41B of the first electrically conductive member 41. The connector 45 may be omitted. The upper-end portion 41B of the first electrically conductive member 41 may be directly fixed to the screw boss 3M by the screw 46.

Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved dust extractors (vacuum cleaners) and methods of using the same.

Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.

All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.

EXPLANATION OF THE REFERENCE NUMBERS

• • 1 Dust extractor
  • 2 Head
  • 3 Tank
  • 3A Front portion
  • 3B Rear portion
  • 3C Left portion
  • 3D Right portion
  • 3E Bottom portion
  • 3F Opening
  • 3G Hose-winding portion
  • 3H Recessed portion
  • 3J Leg portion
  • 3K Projection portion
  • 3L Hole
  • 3M Screw boss
  • 4 Tank cover
  • 5 Latch
  • 6 Dust-extracting hose
  • 7 Suction unit
  • 8 Filter unit
  • 9 Float
  • 10 Battery-mounting part
  • 11 Controller
  • 12 Operation panel
  • 12A Manipulatable dial
  • 12B Display part
  • 13 Top cover
  • 13A Opening
  • 13B Recessed portion
  • 14 Battery cover
  • 15 Handle
  • 16 Cover part
  • 17 Suction tube
  • 17A Ring portion
  • 17B Notched portion
  • 18 Sealing member
  • 19 Inlet port
  • 20 Passageway
  • 21 Joint part
  • 22 Groove
  • 23 Hook
  • 24 Motor
  • 25 Blower fan
  • 26 Motor-housing part
  • 27 Fan-housing part
  • 28 Air-intake port
  • 29 Battery pack
  • 30 Suction nozzle
  • 31 Receptacle
  • 32 Turning path
  • 33 Exhaust path
  • 40 Grounded structure
  • 41 First electrically conductive member
  • 41A Lower-end portion
  • 41B Upper-end portion
  • 42 Second electrically conductive member
  • 42A Intermediate portion
  • 42B Upper-end portion
  • 42C Lower-end portion
  • 42D Hole
  • 43 Lower-end holding member
  • 44 Intermediate holding member
  • 44A First protruding part
  • 44B Second protruding part
  • 45 Connector
  • 46 Screw

Claims

1. A dust extractor comprising:

a head having a top cover;

a tank disposed below the head in an up-down direction of the dust extractor;

a first electrically conductive member mounted on the tank;

a tank cover disposed between the head and the tank, the tank cover including a cover part that covers an opening in an upper-end portion of the tank and a suction tube into which a dust-extracting hose is insertable;

a second electrically conductive member mounted on the tank cover; and

a suction unit that includes a blower fan, which is rotated by a rotational force generated by a motor and thereby generates a suction force in the suction tube;

wherein:

the first electrically conductive member is grounded; and

the second electrically conductive member is electrically connected to the first electrically conductive member.

2. The dust extractor according to claim 1, wherein at least a portion of the second electrically conductive member is disposed in the interior of the suction tube and is configured to contact the dust-extracting hose.

3. The dust extractor according to claim 1, wherein the second electrically conductive member is an elastic member.

4. The dust extractor according to claim 3, wherein the second electrically conductive member includes a leaf spring.

5. The dust extractor according to claim 1, wherein the first electrically conductive member includes a lead line.

6. The dust extractor according to claim 5, further comprising:

a connector mounted on an end portion of the lead line; and

a screw connected to the connector and fixing the connector to the tank;

wherein the second electrically conductive member electrically contacts the screw.

7. The dust extractor according to claim 1, further comprising:

a screw connected to the first electrically conductive member and fixing the first electrically conductive member to the tank;

wherein the second electrically conductive member electrically contacts the screw.

8. The dust extractor according to claim 7, wherein:

a screw boss is provided on an inner surface of the tank; and

the screw fixes the first electrically conductive member to the screw boss.

9. The dust extractor according to claim 1, wherein:

an upper-end portion of the second electrically conductive member is disposed to face a passageway of the suction tube;

a lower-end portion of the second electrically conductive member is disposed below a lower surface of the cover part in the up-down direction; and

an intermediate portion of the second electrically conductive member between the upper-end portion and the lower-end portion is fixed to at least a portion of the tank cover.

10. The dust extractor according to claim 9, wherein the intermediate portion is embedded in a wall of the tank cover.

11. The dust extractor according to claim 10, wherein:

a hole is provided in the intermediate portion; and

at least a portion of the tank cover penetrates into the hole.

12. The dust extractor according to claim 9, wherein:

a ring portion is provided on an inner surface of the suction tube; and

an upper-end portion of the second electrically conductive member is disposed in a notched portion provided in a portion of the ring portion.

13. The dust extractor according to claim 1, wherein the first electrically conductive member is supported by an inner surface of the tank.

14. The dust extractor according to claim 13, further comprising an intermediate holding member that is provided on the inner surface of the tank and holds the first electrically conductive member.

15. The dust extractor according to claim 14, wherein:

the intermediate holding member includes a first protruding part, which protrudes from the inner surface of the tank, and a second protruding part adjacent to the first protruding part; and

the first electrically conductive member is inserted between the first protruding part and the second protruding part.

16. The dust extractor according to claim 1, further comprising:

a lower-end holding member that is inserted into an opening provided in a bottom portion of the tank;

wherein:

at least a portion of the first electrically conductive member is held by the lower-end holding member; and

a lower-end portion of the first electrically conductive member is disposed below a lower surface of the tank in the up-down direction.

17. The dust extractor according to claim 2, wherein:

the second electrically conductive member is an elastic member;

the first electrically conductive member includes a lead line supported by an inner surface of the tank;

an upper-end portion of the second electrically conductive member is disposed to face a passageway of the suction tube;

a lower-end portion of the second electrically conductive member is disposed below a lower surface of the cover part in the up-down direction; and

an intermediate portion of the second electrically conductive member between the upper-end portion and the lower-end portion is fixed to at least a portion of the tank cover.

18. The dust extractor according to claim 17, further comprising:

a lower-end holding member that is inserted into an opening provided in a bottom portion of the tank;

wherein:

at least a portion of the first electrically conductive member is held by the lower-end holding member; and

a lower-end portion of the first electrically conductive member is disposed below a lower surface of the tank in the up-down direction.

19. The dust extractor according to claim 18, wherein the second electrically conductive member includes a leaf spring.

20. The dust extractor according to claim 19, wherein:

the intermediate portion is at least partially embedded in a wall of the tank cover;

a hole is provided in the intermediate portion; and

at least a portion of the tank cover penetrates into the hole.