Abstract: A nailer device has a housing containing a motor and a transmission mechanism. The housing has a nozzle portion with a striking rod for striking a nail arranged therein, the striking rod being moved in a reciprocating manner. A rotating shall is mounted in the housing and the rotating shaft is coupled to the output shaft of the motor through the transmission mechanism. An impact member surrounds the rotating shaft and is moved with the rotating shaft. Corresponding slots are formed on the rotating shaft and the impact member respectively and mate with each other with engagement members being contained in the corresponding slots.

Abstract: In a driving tool, a diameter of an intermediate member is enlarged to increase a mass of the intermediate member and an outside diameter of a cylinder at a position where the intermediate member is internally provided is enlarged in accordance with the enlarged diameter of the intermediate member. Further, in the driving tool, a bearing thickness of a ball bearing is reduced correspondingly to a dimension of the enlarged outside diameter of the cylinder and a washer is provided at a part where the ball bearing abuts on the cylinder in the forward and backward moving direction thereof.

Abstract: A drilling and vibratory jarring device is provided. The device has an inner mandrel shiftable upward or downward in an outer housing from an intermediate position in the outer housing. When the inner mandrel is in the intermediate position within the outer housing mating splines, one set of splines attached to inner mandrel, the other set of splines attached to the outer housing, engage and rotatably lock inner mandrel and outer housing together. When the inner mandrel is shifted to the upward position said splines disengage and the saw-tooth surfaces of an upper pair of jars engage creating longitudinal vibratory forces down-hole when inner mandrel is rotated with respect to outer housing. When the inner mandrel is shifted to the downward position said splines disengage and the saw-tooth surfaces of an lower pair of jars engage creating longitudinal vibratory forces down-hole when inner mandrel is rotated with respect to outer housing.

Abstract: Disclosed is a tool (5) comprising a cam track (A) and cam follower means (B), wherein the cam track (A) comprises a first cam track wall means (15) and the cam follower (B) comprises a first cam follower wall means (15), and the first cam track wall means (10) and first cam follower wall means (15) face one another. The cam track (A) further comprises a second cam track wall means (30) and the cam follower (B) comprise a second cam follower wall means (35), and the second cam track wall means (30) and second cam follower wall means (35) face one another. The first and second cam track wall means (10, 30) are disposed so as to face one another. The first and second cam follower wall means are disposed so as to oppose one another, e.g. back to back. The first/second cam track wall means (10, 30) comprise a first/second cam track wave (20, 40). The second cam follower wall means (15, 35) comprise a first/second cam follower wave (25, 45).

Abstract: A drive mechanism for use with a surgical instrument includes a rotatable drive member, a crank operatively coupled to the drive member; a clutch operatively coupled to the crank, wherein rotational motion of the drive member causes oscillating movement of the clutch; and a gear rotatably coupled to the clutch, wherein the oscillating movement of the clutch causes rotation of the gear. The drive mechanism may further include a gear configured to engage a linear member. The crank may include a pin extending distally therefrom. The clutch may include a slot dimensioned and configured to receive a pin of the crank.

Abstract: A number of cam-operated devices such as power tools (10) are described, the tools having a rotary drive device (24) for rotating a drive shaft (36) having a cylinder cam (42) mounted thereon. A pair of cam followers (54) are located within a cam track (44) provided on the cam member (42), such that rotation of the cam (42) causes axial movement of the cam followers (54), which may be attached to a drive shaft (48) and a tool bit (12). A range of shapes of cam track (44) are described, each of which is non-sinusoidal in shape. Various embodiments of the invention provide non-sinusoidal cam tracks having forward or rearward throw sections which are respectively steeper, shorter, or provide greater acceleration of the cam followers than sinusoidal cam tracks of equivalent wavelength and amplitude. Related piston and cylinder devices and reciprocal drive devices are also described.

Abstract: A drill housing supports an output spindle comprising a material that is relatively soft. The non-rotating hammer member can be mounted around the output spindle, adjacent its forward end, and adjacent the relatively soft material of the drill housing. The non-rotating hammer member can include support slots located along its edge. Support rods that are made of a relatively hard material can extend through the support slots to support the non-rotating hammer member. A plurality of recesses can be provided in the relatively soft material of the drill housing to support the non-rotating hammer member. A hammer mode shift mechanism can be configured to move the non-rotating hammer member along the support rods between a first position corresponding to a non-hammer mode and a second position corresponding to a hammer mode. The relatively hard support rods support the non-rotating hammer member to thereby resist damage to the relatively soft material of the housing member.

Abstract: There is disclosed a tool (5) comprising a cam track (A) and cam follower means (B), wherein a width (WA) of at least a portion of the cam track (A) is greater than a width (WB) of the cam follower means (B). The cam follower means (B) is engaged within the cam track (A), the cam follower means (B) being adapted to run in/around the cam track (A) and be thrown between opposing walls (D, E) of the cam track (A). In use, the cam follower means (B) therefore has two degrees of motion, a first defined by the cam track (A), and a second defined by ricochet between opposing walls (D, E).

Abstract: A vibratory and impact connector for a power tool is provided with a spring, a first drive rod, a drive ring and a second drive rod which are sequentially received in an outer cylinder. The first drive rod is inserted through the spring and extended out of the outer cylinder, the second drive rod is inserted through the drive ring and into the first drive rod, and the drive ring is fixed to the outer cylinder. By such arrangements, driving the second drive rod can rotate the outer cylinder, the first drive rod and the drive ring. Furthermore, by restricting the rotation of the outer cylinder, the drive ring can also be restricted from rotation, and the drive ring and spring can cooperate with a spring to drive the first drive rod to perform axial reciprocation, thus creating an impact operation.

Abstract: A powered hammer includes a housing, a tool holder coupled to the housing and configured to hold a tool, a motor within the housing, a piston slideably mounted within the housing, a drive mechanism that converts rotary output of the motor into a reciprocating motion of the piston, a ram slideably mounted forward of the piston and that is reciprocatingly driven by the piston, and a beat piece support mounted in the housing forward of the ram. A beat piece is slideably supported by the beat piece support. The beat piece is repetitively struck by the ram and that in turn repetitively strikes an end of a tool when the tool is held in the tool holder to transfer the momentum of the ram to a tool. The beat piece support includes a seal that is slidingly engaged by the beat piece. The seal includes an absorbent material.

Abstract: The present invention relates to an arrangement for the repeated mechanical triggering of various types of downhole equipment, the arrangement comprising a spring element (4) and a string section (1).

Abstract: A powered hammer includes a housing, a tool holder coupled to the housing and configured to hold a tool, a motor within the housing, and a piston slideably mounted within the housing. A drive mechanism converts rotary output of the motor into a reciprocating motion of the piston. A ram is slideably mounted within the housing, forward of the piston, and is reciprocatingly driven by the piston. A beat piece is slideably mounted forward of the ram. The beat piece is repetitively struck by the reciprocating ram, which in turn repetitively strikes an end of the tool when held in the tool holder to transfer the momentum of the ram to the tool. A vibration dampener is coupled to the housing and is configured to remove metal splinters from lubricating fluid in the housing while counteracting vibration generated by movement of at least one of the piston, the ram, and the beat piece.

Abstract: The invention relates to a hand power tool, in particular a drill hammer and/or chipping hammer, comprising a hammer unit (10a; 10b) for producing a pulse in the direction of a hammer axis (12a; 12b). Said tool has an axial drive unit (14a; 14b) with a drive element (16a; 16b) and a motor unit (18a; 18b), in addition to a motor shaft (20a; 20b), which forms an angle (22a; 22b) not equal to zero with the hammer axis (12a; 12b) and which co-operates with the axial drive unit (14a; 14b) by means of a torque transmission wheel (24a; 24b) of said unit, the axial drive unit (14a; 14b) being mounted on the opposite side of the torque transmission wheel (24a; 24b) from the motor unit (18a; 18b). The driven element (16a; 16b) of the axial drive unit (14a; 14b) is mounted directly on the torque transmission wheel (24a; 24b).

Abstract: It is an object of the invention to provide a technique that contributes to further improvement of an impact tool. A representative impact tool includes a motor, a tool body that houses the motor, a dynamic vibration reducer and a driving mechanism part that is driven by the motor and forcibly drives the dynamic vibration reducer by applying an external force other than vibration of the tool body to the dynamic vibration reducer, during hammering operation. At least one of the dynamic vibration reducer and the driving mechanism part is mounted to the tool body in a form of an assembly into which at least one of a plurality of component parts forming the dynamic vibration reducer and a plurality of component parts forming the driving mechanism part are assembled in advance.

Abstract: An actuator is arranged in a housing of an electrical nail gun. The actuator includes a sliding base, an external-running brushless direct current motor, a swing base and an electric driver. The sliding base is slidably disposed on an end of a located supporter which is positioned in the housing. The sliding base loads a spring and forms a hitting nail bar thereon. The motor has a stator and a rotator attached on an outer wall of the stator. A flywheel is driven by the motor and is configured to engage or disengage with/from the sliding base. The swing base is pivotally mounted on the housing. The swing base is adjacent to the sliding base and the supporter. The motor is installed in the swing base. The electric driver is attached to the housing and is adjacent to an end side of the swing base. The electric driver has a rod member driven by electricity.

Abstract: A hammer includes a housing; a motor mounted within the housing; and a tool holder rotatably mounted on the house for holding a cutting tool. A striker is mounted in a freely slideable manner within the housing, for repetitively striking an end of a cutting tool when a cutting tool is held by the tool holder. The striker is reciprocatingly driven by the motor, when the motor is activated, via a drive mechanism. The drive mechanism comprises: a pivoting drive arm pivotally mounted within the housing at one end and which is drivingly connected to the striker; a pivotal drive mechanism connected to the pivoting drive arm and which converts a rotary movement generated by the motor into an oscillating pivotal movement of the pivoting drive arm; and the amplitude of the oscillations of the pivoting drive arm can be adjusted.

Abstract: A power tool suppressing expansion of the air in a chamber and preventing lubricant encapsulated in the chamber from being leaked outside of the chamber. A communication portion communicates a speed reduction chamber with a motor housing communicating with an atmosphere. A communication passage forming component made from an elastic material is fittingly inserted into the communication portion which forms a communication passage including a plurality of impediment portions. When the air containing lubrication component is passed through the communication passage, the air collides against the impediment portions, allowing grease component to be adhered to the impediment portions.

Abstract: A hammer comprising a housing 2; a motor mounted within the housing; a tool holder 8 rotatably mounted on the housing 2 for holding a cutting tool; striker mounted in a freely slideable manner within the housing, for repetitively striking an end of a cutting tool when a cutting tool is held by the tool holder 8, which striker is reciprocatingly driven by the motor, when the motor is activated, via a drive mechanism; wherein the drive mechanism comprises: a pivoting drive arm pivotally mounted within the housing 2 at one end; a pivotal drive mechanism connected to the pivoting drive arm which converts a rotary movement generated by the motor to a pivoting movement of the pivoting drive arm about its pivot point the pivotal drive mechanism comprising a circular cam formed around the circumference of a lengthwise section of a rotatable shaft and a cam follower connected to the pivoting drive arm which engages with the cam and follows the path of the cam when the shaft is rotated; characterised in that a spring i

Abstract: A vibration reduction apparatus for use with a hammer tool having a hammer piston is disclosed. The hammer piston is caused to reciprocate in the cylinder by rotation of a gear wheel and crank drive. A cam is mounted around the gear wheel, a counterweight surrounds the piston cylinder, and a cam follower is provided on the counterweight. The cam follower on the counterweight is urged into contact with the cam by a biasing element. The external profile of the cam is such that rotation of the gear wheel causes oscillation of the counterweight in antiphase to motion of the hammer piston to counteract vibrations produced by operation of the hammer action of the tool. A mechanism is provided to deactivate the vibration reduction apparatus when the hammer action of the tool is deactivated.

Abstract: A rotary hammer incorporating both a reciprocating drive for generating a first hammering action transmittable to a tool bit and ratcheting mechanism for generating a second hammering action transmittable to the tool bit. The first hammering action and the second hammering actions differing in frequency and force of the impacts transmitted to the tool bit. Furthermore, the reciprocating drive and ratcheting mechanism are selectably engageable so that the first hammering action and the second hammering action may be selectably transmitted to the tool bit individually or in combination depending on the desired mode operation.

Abstract: A reciprocating drive mechanism for a striker in a hammer, a rotary hammer, or a power drill having a hammer action, includes a sinusoidal cam channel formed on a drive member and a cam follower, in the form of a ball bearing, attached to a driven member which, due to the interaction of the cam and cam follower, results in a reciprocating movement of the driven member. Both the drive member and driven member can be rotatingly driven by a motor, their relative speeds resulting in the reciprocating movement of the driven member. The driven member is connected to the striker either via a mechanical helical spring or an air spring.

Abstract: A stationary annular abutting member 14E is provided with a first projecting section that operates as part of a ratchet mechanism. A rotational flange section is provided with a second projecting section that operates as part of the ratchet mechanism. The first projecting section projects in the direction from the ON position toward the OFF position of a plunger of a solenoid. The second projecting section projects in the direction from the OFF position toward the ON position of the plunger. When a driven rotor starts rotating and comes to a rotary position slightly short of the rotary position of about ¾ of a full turn in the ON state of the solenoid, the projecting end of the first projecting section and that of the second projecting section are located opposite to each other and the second projecting section rides on the first projecting section.

Abstract: A hand power tool has a tool spindle rotatable by a drive train, a cam device located in the drive train and having two cam discs in engagement with one another for transmitting axial percussion motions to the tool spindle, an overloading coupling located in the drive train and having two coupling parts which are in engagement with one another and are overloadable counter to an axially exerted force, a blocking device which upon its activation blocks a relative rotation of the coupling parts of the overloading coupling to one another, and an operating mode setting device for setting “percussion drilling”, “drilling” and “screw driving” operating modes, and also a magnitude of an overlocking moment upon screwdriving and having one torque adjusting ring for setting the “drilling” operating mode and the “screwdriving” operating mode, with preselection of the magnitude of the overlocking moment, and another adjusting the “percussion drilling” operating mode on and off, and in “on” position overrides any operating

Abstract: An impact drill includes a first ratchet together with a spindle and movable in an axial direction, and a second ratchet engageable with the first ratchet. The second ratchet can be moved in the axial direction, and rotated with a predetermined range in a rotational direction.

Abstract: An impact mechanism for a hammer drill, which has a housing and a drill bit protruding outside the housing, is provided. The mechanism includes firstly an impact platform within the housing; the impact platform is in connection with the drill bit for receiving impact forces and for transferring the impact forces to the drill bit. The mechanism also has a plurality of cams within the housing, and the plurality of cams are angularly spaced apart and arranged about an axis of rotation. The mechanism further includes a plurality of hammers placed within the housing and interactable with both the impact platform and the plurality of cams. The plurality of hammers are angularly spaced apart and arranged about the axis of rotation, and each hammer is capable of reciprocating along the axis for exerting the impact forces on the impact platform.

Abstract: A preferred embodiment of a rotary tool reciprocating motion conversion attachment for a rotary power hand tool is described which is configured to be attached to a nose portion of the hand tool housing. The attachment has a rotary drive train in a housing that is connectable to the output shaft of the hand tool, the drive train driving a barrel cam having an exterior cam groove. A cam follower rides in the cam groove and produces reciprocating motion, with the cam follower being part of a cam follower assembly to which an implement holder is attached. The preferred embodiment has a cam groove configuration which causes the implement holder to move slower during a cutting stroke and faster during a return stroke, thereby tending to optimize the operation of the cutting implement. The preferred embodiment also includes a planetary gear set for reducing the rotational speed of the hand tool output shaft to reduce the speed of reciprocation of the attachment.

Abstract: An electric power tool includes a housing, an inner case and a hammer case. The housing receiving a motor has a pair of half portions. The inner case receives a planetary gear train. An input side of the planetary gear train is connected to a drive shaft of the motor. The housing receives the inner case. The hammer case receives a hammer unit. An input side of the hammer unit is connected to an output shaft of the planetary gear train to convert rotation of the output shaft of the planetary gear train into an intermittent striking power outputted from an output shaft of the hammer unit. The hammer case receives the inner case having recesses. The hammer case has elongated holes aligned with the recesses. Each half portion has bosses engaging with the elongated holes of the hammer case, which are aligned with the recesses of the inner case.

Abstract: An apparatus for providing percussion action in a rotary power tool having a rotary output shaft, the apparatus comprising at least one moveable mass adapted to have a component of movement parallel to the axis of the rotary output shaft to cause impacts to be applied to a working member of the tool; and a device for intermittently converting rotary movement of the rotary output shaft into movement of at least one the moveable mass to cause the impacts to be applied to the working member.

Abstract: The invention relates to a device for limiting torque to be transferred, having first and second shafts having a longitudinal axis; at least first and second transfer elements arranged coaxial with the longitudinal axis of the first and second shafts, the first transfer element associated with the first shaft and the second transfer element associated with the second shaft; the two transfer elements having substantially complementary engaging faces; at least one elastic element configured to bias the engaging faces of the first and second transfer elements into engagement with each other; wherein an engaging face of the first transfer element has a first engageable contour, and an engaging face of the second transfer element has a second engageable contour, wherein first and second engageable contours each have first and second active angles and a first passive angle.

Abstract: A fastening tool that drives a fastener into a work-piece. The tool includes a motor that is connected to a transmission. The transmission includes a flywheel. The tool also includes a driver mechanism that is adapted to drive the fastener into the work-piece. The flywheel is connected to the driver mechanism when the flywheel is in a flywheel firing position. The tool includes a control module that detects a flywheel position and compares the flywheel position to the flywheel firing position. The control module also adjusts the flywheel position based on the comparison. The control module ensures that the transmission has enough rotations to ensure that enough momentum can be generated to drive the fastener into the work-piece.

Abstract: A rotary tool, such as an impact wrench, includes a housing having a forward end and supporting a motor. The motor has a motor shaft extending axially through the housing and defining an axis. The rotary tool further includes a frame coupled to the motor shaft and rotatable relative to the housing about the axis in response to rotation of the motor shaft. The frame defines an interior space. The rotary tool also includes a piston supported by the frame and moveable axially in the interior space and an output shaft supported in the forward end of the housing and rotatable about the axis. The output shaft has a plurality of cams. The piston is engageable with the plurality of cams to intermittently hammer the output shaft.

Abstract: An impact tool driver includes a hollow holding member having a surrounding wall defining a chamber. A solid and rigid shank of a handle is formed with a V-shaped cam hole, and extends into the chamber such that the V-shaped cam hole is registered with two diametrically disposed pin holes in the surrounding wall. A compression spring is disposed within the chamber in the holding member, and abuts against the shank and the holding member. A pin extends through the pin holes in the surrounding wall and the cam hole in the handle, and slidably contacts a cam face that defines the cam hole.

Abstract: Percussion device, includes a housing and two movable bodies, an impact body for an impact pin protruding from the housing, and a balancing body for counterbalancing impact motions of the impact body. The housing includes springs, which constantly strive to bring the bodies towards each other and against the action of which the bodies may be separated axially. The balancing body is rotatable, via a drive spindle connected to a driving source the spindle being mounted in a bearing member, at least one of the bodies including an oblique surface, which, by contact against the other body, transforms the rotary motion of the balancing body into axial motions of the impact body. Rotation of the bearing member is prevented by a helical pressure spring attached to the bearing member and the housing. In this way, tangential vibrations cannot be transferred from the drive spindle to the housing.

Abstract: This invention relates to the design of a pin clutch to allow for coupling of a rotational shaft to an output mechanism in a synchronous fashion. Specifically, this is related to impacting or operations requiring intermittent or semi-intermittent coupling of an input mechanism or shaft to an output mechanism or shaft. Devices of this nature include fastening tools, throwing mechanisms and other devices in which input energy is built up during a portion of a cycle followed by the coupling and release of that energy to an output mechanism.

Abstract: A portable electric nailing gun operating from a power source. The motor accelerates a flywheel which at the appropriate energy state is coupled through a mechanism to an anvil acting directly on the nail. The motor accelerates a flywheel that is then clutched to the output anvil causing the nail to be driven. The position of the output anvil is sensed and once the nail is driven, the motor is dynamically braked reducing the excess energy in the flywheel. This method uses a highly responsive motor and power source which enables the motor to come up to speed, drive the nail and return to a low energy condition in less than 2 seconds. The electrical control circuit and brake allow precise control and improve safety. The power source is preferably a rechargeable low impedance battery.

Abstract: A gear assembly for a power tool. The gear assembly includes a gear assembly housing, a ring gear supported by the gear assembly housing, one of the gear assembly housing and the ring gear having an end defining a first bearing race, a planetary gear carrier member supported for rotation relative to the ring gear and defining a second bearing race, the carrier member being drivingly engageable with a tool element to drive the tool element, a plurality of planet gears supported by the carrier member and drivingly connectable to the gear end of the drive shaft of the motor, the plurality of planet gears interacting with a ring gear to rotatably drive the carrier member, and a plurality of bearing members supported between the first bearing race and the second bearing race.

Abstract: An impact driver (1) includes a main housing (2) encasing a motor (5); an internal gear case (8) which is secured by screws to the main housing (2) and is provided with an externally threaded portion (12); and a hammer case (13) with an internally threaded portion (14) which is adapted for threadable engagement with the externally threaded portion (12) of the internal gear case (8) so as to couple the hammer case (13) to the internal gear case (8). The impact driver (1) additionally includes a rotation stop mechanism comprised of a rack (24) disposed within a forward extending portion (23) of the main housing (2) for meshing with dimples (27) formed in the outer surface of the hammer case (13). By fixing the rack (24) with a feed screw (26) disposed transversely in the forward extending portion (23), the hammer case (13) is prevented from rotation with respect to the internal gear case (8) after assembly of the impact driver (1).

Abstract: A portable electric nailing gun operating from a power supply. The motor accelerates a flywheel, which at the appropriate energy state is coupled through a mechanism to an anvil acting directly on the nail. The actuation is governed by a control circuit and initiated from a trigger switch. The stored energy delivered from the motor is coupled to the output anvil drives the nail. At least one position of the output anvil is sensed and once the nail is driven, the power is disconnected from the motor. This method uses a direct acting clutch and a harmonic motion nailing mechanism to reduce wear and increase robustness of the nailer. Elastic elements are used to limit stresses during the impact periods. The electrical control circuit and sensors allow precise control and improve safety. The power supply is preferably a rechargeable low impedance battery pack.

Abstract: A number of cam-operated devices such as power tools 10 are described, the tools having rotary drive means 24 for rotating a drive shaft 36 having a cylinder cam 42 mounted thereon. A pair of cam followers 54 are located within a cam track 44 provided on the cam member 42, such that rotation of the cam 42 causes axial movement of the cam followers 54, which may be attached to a drive shaft 48 and a tool bit 12.

Abstract: A hammer drill with rolling contact at the contact surfaces for transmission of axial force between a drive shaft and hammer shaft. In the case of ball bearings, point contact is obtained. In the case of roller bearings, line contact is obtained. The area of contact is thus close to zero as opposed to a relatively large area in engagement systems using toothed surfaces. Use of point or line contact reduces heat generation and reduces energy loss due to friction.

Abstract: Disclosed and taught is a novel drive mechanism for a cyclic operating tool employing an energized flywheel to provide the necessary energy to perform a working cycle. The drive mechanism disclosed is particularly useful in hand tool applications such as a hand held nailing machine. The flywheel may be energized by a corded or battery powered motor. The herein disclosed mechanism teaches a novel pair of ball ramp cam plates wherein a first pair of ball ramps cause an initial engagement of a clutch with the energized flywheel whereupon rotation of the clutch causes activation of a second pair of ball ramps which affect compression of a spring which acts to increase the pressure applied to the clutch thereby assuring a slip free engagement between the clutch and he flywheel throughout the working cycle of the drive mechanism.

Abstract: An apparatus for providing repetitive percussive blows in tools and the like comprises an elongated hammer movable along its longitudinal axis from an extended position to a retracted position. A bias element urges the hammer towards the extended position. A cam member is attached to a face of a rotating drive member at a point removed from the drive member's rotational axis. The cam member bears against the hammer during only a portion of each revolution of the drive member so as to move the hammer against the bias force from the extended position to the retracted position and then release the hammer, which then moves toward the extended position to deliver a percussive blow.

Abstract: A portable electric nailing gun operating from a power supply. The motor accelerates a flywheel which at the appropriate energy state is coupled through a mechanism to an anvil acting directly on the nail. The actuation is governed by a control circuit and initiated from a trigger switch. The motor accelerates a flywheel that is then clutched to the output anvil causing the nail to be driven. The position of the output anvil is sensed and once the nail is driven, the motor is dynamically braked reducing the excess energy in the flywheel. This method uses a highly responsive motor and power supply which enables the motor to come up to speed, drive the nail and return to a low energy condition in less than 2 seconds. The electrical control circuit and brake allow precise control and improve safety. The power supply is preferably a rechargeable low impedance battery.

Abstract: A hammer drill has a motor which drives an axially displaceable intermediate gear mounted in an intermediate gear arrangement. An impact mechanism is formed by including interacting impact cams between either the intermediate gear and the housing, or the motor armature shaft and the housing to generate a reciprocating motion on an output spindle or shaft. A spindle locking mechanism is included which causes an intermediate gear to be disengageable with respect to the output shaft, while still permitting the impact mechanism to be engaged. Such an arrangement allows the hammer drill to operate in a hammer-only or chipping mode.

Abstract: An automatic fastening scheduler apparatus is described for scheduling the placement of fasteners such as nails, staples or screws for joining materials along a preselected path on the material. The apparatus spaces the fasteners by sequentially operating the safety mechanism of a standard power fastener at a rate determined by the distance the apparatus is rolled along the surface of the material. The apparatus does not modify the operation of the safety mechanism of the power fastener and the power fastener can be easily removed from the apparatus for manual operation. The apparatus provides for varying the spacing between adjacent fasteners and can be operated from either an upright or a crouched position.

Abstract: In a conventional impact generator, a grease receives centrifugal force by the rotation of a rotary member, thereby keeping away from surfaces of the rotary member and a weight. Consequently, insufficient lubrication is caused between the weight and a member (for example, a tappet and the like) which comes in contact with the weight. An impact generator D comprises an impregnating member 60 capable of impregnating the grease. The impregnating member 60 is extended from a vicinity of an inner peripheral wall surface 59 of a chamber E1 for accommodating a rotary member 10 and a weight 30 to a position where the impregnating member 60 comes in contact with the weight 30 performing a circular motion.

Abstract: In a conventional impact generator, a great shock is generated when a weight collides with a rotary member, and a rotary shaft of the rotary member and a bearing supporting the rotary shaft receive the great shock. Therefore, it is necessary to employ a bearing having a great load capacity. Furthermore, great vibrations and noises are also generated in the impact generator. A rotary member (10) is rotatably supported by rotary shafts (11) and (12). A weight (30) is movably held by the rotary member (10). A shock absorber (40) for absorbing, by elastic force, a shock generated between the weight (30) and the rotary member (10) is provided between the weight (30) and the rotary member (10).

Abstract: A cable-cutting apparatus includes a housing, a cutter rod with a fixed blade, an impact rod, a resilient unit for biasing the impact rod to press against the cutter rod, a rotating unit, and a driving unit. Normally, an engagement surface of the impact rod abuts against an engagement surface of the cutter rod. When the blade presses a cable against a planar surface, and when a switch of the driving unit is actuated to rotate the rotating unit, the engagement surface of the impact rod moves rearward away from the engagement surface of the cutter rod against the biasing action of the spring until the push rod reaches a rear limit position, after which the impact rod is biased by the spring to move forward to impact on the cutter rod, thereby cutting the cable with the blade.

Abstract: A retaining device for a power drill has multiple brake shoes movably received in the housing, a cam securely engaged with the output shaft to selectively abut the brake shoes to move and engage with an inner periphery of a through hole and a driving disk provided to drive the output shaft and to limit the movement of the brake shoes in the housing. When the brake shoes are moved to engage with the inner periphery defining the through hole, a locking effect is provided to the driving disk so as to the output shaft.

Abstract: A hand-controlled motor-driven oscillating device having an elongate casing, an electric motor having an output shaft, and an oscillating unit having an output shaft and being connected in drive terms to the output shaft of the electric motor. The electric motor and the oscillating motor and the oscillating unit are arranged in the casing in succession in a direction of the longitudinal access of the casing so as to form a grip section and an oscillating head section. The output shaft of the oscillating unit projects out of the casing. The grip section is connected to the oscillating head section so that the grip section can be pivoted, in terms of its angular position, with respect to the oscillating head section and the oscillating unit output shaft.