Tool adapter

Abstract

The invention is based on a tool adapter (30), for fastening a disklike tool (12) on a slaving device (16) of a hand power tool, that has a tool retention means (36) for connection to the tool (12). It is proposed that the tool adapter (30) includes a fastening means (52, 54) for form-locking connection with the slaving device (16).

Description

PRIOR ART

The invention is based on a tool adapter as generically defined by the preamble to claim 1.

Rubber plates for fastening sheets of sandpaper To a power drill, for instance, are known that are fastened in force-locking fashion in the chuck of the power drill. The sheet of sandpaper is retained on the rubber plate by a larger slaving disk, which in turn is connected to the rubber plate by a screw.

ADVANTAGES OF THE INVENTION

The invention is based on a tool adapter, for fastening a disklike tool on a slaving device of a hand power tool, that has a tool retention means for connection to the tool.

It is proposed that the tool adapter includes a fastening means for form-locking connection with the slaving device. Tools can be connected to the slaving device of the hand power tool and need not be adapted in their design to the slaving device. For instance, a tool with a simple hub that has no special fastening means can be located on a slaving device with specially designed fastening elements. By means of the form lock, an especially stable retention of the tool adapter on the slaving device can be assured.

The tool adapter is prepared such that it can be secured to the slaving device of a complete hand power tool. The slaving device of the hand power tool is thus a tool slaving device. The tool adapter is therefore not part of the hand power tool but instead is a separate component, independent of the hand power tool, and can be secured like a tool to the slaving device.

The tool retention means is advantageously provided for force-locking connection to the tool, and as a result simple fastening of the tool can be achieved. The tool can, in addition to the force lock, be retained by an additional form lock. The force lock is expediently effected in the tangential direction, while the additional form lock is effected in the axial direction. The tool can be retained especially simply and yet firmly and securely on the tool adapter. The tool retention means may have a threaded element, by which the force and form lock are established.

Expediently, the tool retention means includes a centering element. An imbalance of the tool during a machining operation can be counteracted.

In a further feature of the invention, it is proposed that the fastening means is provided for form-locking connection in the tangential direction with the slaving device. A strong force moment can be transmitted to a rotating tool without requiring that the tool adapter be chucked in force-locking fashion.

Advantageously, the fastening means is formed by a cup-shaped element. A relatively large area for absorbing a strong driving force can be used on the inner or outer wall of the cup-shaped element. Wear of the fastening means and hence of the tool adapter can be counteracted. The cup-shaped element may be embodied with a cap or a partial cap, or it may be embodied entirely without a cap, for instance in the form of a hollow-cylindrical element.

The tool adapter can be securely connected to the slaving device without chucking if the fastening means is provided for form-locking connection with the slaving device in the axial direction. In addition, a form lock with the slaving device in the tangential direction may be provided. An especially secure form lock in the axial direction can be attained if the fastening means includes a retaining element, which can be grasped from behind in the axial direction. The retaining element thus has one side facing away from the slaving device that can be braced in the axial direction by a retaining means, which for instance is hook-shaped, of the slaving device. The retaining element is designed in particular in the form of a segment of a circle, so that by a rotary motion of at least part of the tool adapter it can be rotated underneath a retaining means of the slaving device. By this rotation, locking of the tool adapter in the axial direction on the slaving device can be attained.

A form-locking connection of the tool adapter with the slaving device, especially in the axial direction, can be attained in an especially simple way if the fastening means includes an opening through a plate element that extends in the radial direction. A retaining means, guided through this opening, of the slaving device can secure the plate element and thus the tool adapter in the axial direction and expediently also in the tangential direction by force-locking engagement. The main element is platelike, at least in part, and is for instance a metal sheet.

By means of a centering element for centered mounting on the slaving device, an imbalance of the tool adapter during a machining operation can be counteracted in a simple way. The centering element is for instance a centering opening, particularly through the plate element, and as a result centering can be achieved even without a corresponding opening in the slaving device. The slaving device can be constructed in compact form.

Advantageously, the centering element has at least one recess in the radial direction. As a result, the tool adapter can be adapted to a code on the slaving device, and an unambiguous association can be made between the tool adapter and a coded slaving device.

Suitability of the tool adapter for a fast-action chucking system can be attained by means of a pushbutton element located on one side of the tool. The pushbutton element can be operated from the side on which the tool is located on the tool adapter and is thus easily accessible. By means of the pushbutton element, a release device in the slaving device can be actuated, and the tool adapter can be released from the slaving device in an especially simple way. The pushbutton element may have any suitable shape and is a function element that is displaceable by pressure relative to its surroundings.

Expediently, the pushbutton element is located at least partly in the tool retention means. As a result, a central position of the pushbutton element in the tool adapter can be attained and hence an imbalance of the tool adapter can be counteracted.

Advantageously, the pushbutton element can be operated from one side of the tool, and on a slaving side diametrically opposite that side of the tool, it includes a function element. The slaving side, during a work operation, is oriented toward the slaving device, and therefore the slaving-side function element can actuate a corresponding function element of the slaving device, such as a pushbutton element, directly or indirectly.

To avoid unintentional actuation of the pushbutton element, the pushbutton element has an operation element, which in the unactuated state is at least for the most part sunken in an indentation. Additional safety can be achieved by means of a spring element, which is prestressed for preloading the pushbutton element counter to an actuation direction.

Simple manufacture of the tool adapter can be attained by a first main element that includes the tool retention means and a second main element, separable from the first main element, that includes the fastening means. The tool retention means and the fastening means can thus be produced separately and connected firmly to one another indirectly or directly by means of suitable connection means for firm connection of the two main elements, such as screws.

DRAWINGS

Further advantages will become apparent from the ensuing description of the drawings. In the drawings, one exemplary embodiment of the invention is shown. The drawings, description and claims include numerous characteristics in combination. One skilled in the art will expediently consider these characteristics individually as well and put them together to make useful further combinations.

Shown are:

FIG. 1, a right-angle grinder with a cutting wheel;

FIG. 2, a slaving device of the right-angle grinder;

FIG. 3, an exploded view of a tool adapter; and

FIG. 4, a main element of the tool adapter, with the cutting wheel secured to it.

DESCRIPTION OF THE EXEMPLARY EMBODIMENT

FIG. 1 shows a right-angle grinder 2 from above, with an electric motor, not identified by reference numeral, supported in a housing 4. The right-angle grinder 2 can be guided via two handles 6, 8. Via the electric motor, a gear, not shown, in a gearbox 10, and a likewise not visible driveshaft, a tool 12 embodied as a cutting wheel can be driven in a tangential direction 14.

If the right-angle grinder 2 is viewed not from above as in FIG. 1 but rather from below and the tool 12 is removed, then a slaving device 16 of the right-angle grinder 2 becomes visible. This slaving device 16 is shown in FIG. 2 in perspective, isolated from the other components of the right-angle grinder. The slaving device 16 includes a slaving flange 18, a centering collar 20, three identical fastening elements embodied as detent bolts 22, and three likewise identical fastening elements 24, embodied as clamping hooks. An actuation button 26 is located centrally inside the centering collar 20. Three encoding projections 28 protrude radially outward from the centering collar 20.

FIG. 3 shows a tool adapter 30 with a first main element 32, shown at the top in FIG. 3, and a second main element 34, shown below the first main element 32. A tool retention means 36, which includes a threaded element 38 and a centering element 40, is a component of the first main element 32. A pushbutton element 42 is located partly inside the tool retention means 36; on a side toward the tool, it includes an actuating element 44, and on a slaving side it includes a function element 46. The actuating element 44, for the sake of simple assembly, is screwed onto a central core of the pushbutton element 42.

The second main element 34 includes a plate element 50 inside a connecting flange 48; the plate element includes three first fastening means 52, embodied as a cup-shaped indentation, and three fastening means 54 each with one opening 56. A centering element 58 embodied as an opening is located centrally in the plate element 50 and has three radial recesses 60, of which only one, however, is visible. For firmly connecting the two main elements 32, 34 to one another, the tool adapter 30 includes four screws 62, each passed through a respective hole 64 in the connecting flange 48 and screwed into a threaded bore 66 in the first main element 32. It is also possible for the two main elements 32, 34, after their manufacture, to be connected by material engagement to one another, for instance by welding. Manufacturing the tool adapter 30 in one piece is also conceivable.

The slaving device 16 shown in FIG. 2 is designed as a fast-action chucking system, onto which tools can be fastened simply, quickly and securely with a tool hub designed to suit the plate element 50. Disklike tools such as grinding wheels, roughing disks, cutting wheels, sawblades, or the like of simple design, however, typically have only a single circular centering opening and cannot be connected to the slaving device 16. It may be desirable, however, for even such simple tools to be connected to the slaving device 16. To that end, the tool adapter 30 is provided. The tool adapter 30 can be connected to the slaving device 16 and can in turn itself receive simple disklike tools.

For connecting the tool adapter 30 to the slaving device 16, the centering element 58 is slipped onto the centering collar 20. After it is slipped on, the plate element 50 rests on the three encoding projections 28 and can now be rotated in the tangential direction 14, until the three recesses 60 cover the three encoding projections 28. In this position, the plate element 50—and with it the entire tool adapter 30—drops somewhat lower, until it comes to rest on the three detent bolts 22. These three detent bolts 22 are spring-loaded and can be pressed downward by a user of the right-angle grinder 2 by pressure on the tool adapter 30, until the tool adapter 30 rests on the slaving flange 18. As a result, the hook-like fastening elements 24 pass through the openings 56.

For fastening the tool adapter 30 to the slaving device 16, the plate element 50 can now be rotated clockwise, as a result of which a radially innermost region of the plate element 50 is moved underneath the encoding projections 28.

Simultaneously, a retaining element 68 of the fastening means 54, adjacent the respective openings 56 and embodied in the tangential direction parallel to an opening 56, is thrust beneath an obliquely oriented ramp element 70 of the fastening element 24, whereupon the fastening element 24 is drawn upward somewhat along the force of a prestressed spring, not shown. A precise description of the slaving device 16, the spring-loaded detent bolts 22, and the fastening elements 24 can be found in International Patent Disclosure WO 03/097299.

Upon further rotation of the plate element 50 and tool adapter 30 clockwise, the retaining element 68 is thrust beneath a lug 72, oriented parallel to the slaving flange 18, which with the aid of the prestressed spring, not shown, presses the plate element 50 onto the slaving flange 18. When a fastening position is reached, the detent bolts 22 come to coincide with the cup-shaped fastening means 52 of the tool adapter 30 and by racing upward snap into these fastening means 52. The plate element 50—and with it the entire tool adapter 30—is now fixed in the cup-like fastening means 52 in the tangential direction 14 by the detent bolts 22 and in the axial direction by the spring-loaded fastening elements 24 that engage the retaining elements 68 from behind.

The tool 12 can now be chucked on the first main element 32, located on the tool side; the order in which the connections are made, of the tool to the first main element 32, of the first main element 32 to the second main element 34, and of the second main element 34 to the slaving device 16, is arbitrary. The tool 12 is guided, by a centrally embodied centering opening, not shown, over the tool retention means 36 and placed around the centering element 40. Next, a pressure element 74, embodied as a lock nut, shown in FIG. 4 is threaded with its female thread onto the threaded element 38, specifically until the tool 12 is firmly clamped between a base plate 76 of the main element 32 and the pressure element 74. Instead of a lock nut, some other clamping element that suitably cooperates with the tool retention means may equally well be used; the threaded element 38 may optionally be replaced by some other suitable element.

For applying the force required for tensing the pressure element 74, the pressure element 74 is embodied with a hexagonal outer shape, like a tool nut, and can be retained by a wrench. To generate a necessary contrary force, any spindle lock that may be present for the right-angle grinder 2 can be actuated; this prevents slaved rotation of the slaving device 16. For cases in which the right-angle grinder 2 has no such spindle lock, the main elements 32, 34 are each embodied with two flat faces 78, which can likewise be engaged by a large wrench. Now the two wrenches can be rotated counter to one another about the faces 78 and about the pressure element 74 until the pressure element 74 presses the tool 12 firmly against the base plate 76. The tool 12 is now secured to the tool adapter 30.

For releasing the tool adapter 30 from the slaving device 16, the user of the right-angle grinder 2 can press the actuating element 44 in the axial direction toward the gearbox 10 of the right-angle grinder 2, and as a result the function element 46 on the slaving side presses against the actuation button 26 of the slaving device 16. As a result, the detent bolts 22 are pulled downward and out of the cup-shaped fastening means 52. The tool adapter 30 can be rotated counterclockwise and released from the slaving device 16.

To prevent unintentional actuation of the pushbutton element 42, the actuating element 44 is sunk completely inside the pressure element 74. The pushbutton element 42 is furthermore prestressed in the axial direction away from the gearbox by a spring element 80 embodied as a spiral spring, so that in operation, even if the tool adapter 30 experiences strong impacts, the actuation button 26 will not be actuated unintentionally by the weight of the pushbutton element 42 alone.

Claims

1. A tool adapter (30), for fastening a disklike tool (12) on a slaving device (16) of a hand power tool, that has a tool retention means (36) for connection to the tool (12), characterized by a fastening means (52, 54) for form-locking connection with the slaving device (16).

2. The tool adapter (30) in accordance with claim 1, characterized in that the tool retention means (36) is provided for force-locking connection of the tool (12) in the tangential direction (14) and for form-locking connection of the tool (12) in the axial direction.

3. The tool adapter (30) in accordance with claim 1, characterized in that the fastening means (52) is provided for form-locking connection in the tangential direction (14) with the slaving device (16).

4. The tool adapter (30) in accordance with claim 1, characterized in that the fastening means (52) is formed by a cup-shaped element.

5. The tool adapter (30) in accordance with claim 1, characterized in that the fastening means (54) is provided for form-locking connection with the slaving device (16) in the axial direction.

6. The tool adapter (30) in accordance with claim 1, characterized in that the fastening means (54) includes an opening (56) through a plate element (50) that extends in the radial direction.

7. The tool adapter (30) in accordance with claim 1, characterized by a centering element (58) for centered mounting on the slaving device (16).

8. The tool adapter (30) in accordance with claim 7, characterized in that the centering element (58) has at least one recess (60) in the radial direction.

9. The tool adapter (30) in accordance with claim 1, characterized by a pushbutton element (42) located on one side of the tool.

10. The tool adapter (30) in accordance with claim 9, characterized in that the pushbutton element (42) is located at least partly in the tool retention means (36).

11. The tool adapter (30) in accordance with claim 9, characterized in that the pushbutton element (42) can be operated from one side of the tool, and on a slaving side diametrically opposite that side of the tool, it includes a function element (46).

12. The tool adapter (30) in accordance with claim 1, characterized by a first main element (32) that includes the tool retention means (36) and a second main element (34), separable from the first main element (32), that includes the fastening means (52, 54).