Abstract: A portable power tool includes a housing, and an impact mechanism movably supported in the housing and having a front opening for receiving a working implement and a hammer piston for delivering hammer blows to the working implement. The impact mechanism is supported in the housing by a pivot device in a point located between the forward and rear ends of the impact mechanism and allowing longitudinal and pivotal movements but preventing in the support point radial and rotational movements of the impact mechanism relative to the housing. A resilient device is located at a distance from the pivot device and is arranged to bias the impact mechanism to a neutral position relative to the housing and to absorb vibration movements of the impact mechanism to protect the housing against such vibration movements.

Abstract: A pneumatic hammer drill includes: a pneumatic cylinder having a cylinder rear end fitted in a handle body, an air passage, and a pressure chamber; and an air valve adjacent to the cylinder rear end. The air valve has a front bearing end, a valve orifice interconnecting fluidly the air passage and the pressure chamber, and an opening disposed at the front bearing end in communication with the valve orifice. A piston is disposed slidably in the pressure chamber, and has a piston rear end capable of moving towards or away from the front bearing end. An air trap arrangement is associated with the piston rear end and the front bearing end to trap air between the same and around the opening so as to provide a shock-absorbing air cushion when the piston rear end moves towards the front bearing end.

Abstract: A handle assembly for a power tool 1 comprises a housing 2 defining a handle 4 and housing a motor for actuating an output member of the tool, such as a drill bit or jigsaw blade. The handle assembly comprises at least one flexible sheet 8 adapted to be mounted to a surface of the handle of the power tool and having a series of protrusions 10 adapted to be engaged by a hand of a user of the tool. The protrusions 10 retain one or more blister packs (not shown) containing at least one vibration damping gel material between the flexible sheet 8 and the surface of the handle 4.

Abstract: A device and method for vibration control in a machine for cutting, said machine comprising a cutting tool supported by a tool holder. The device comprises a control unit and converting means which are connectible to the control unit and comprise a vibration sensor and an actuator. The actuator comprises an active element which converts an A.C. voltage supplied by the control unit to the actuator into dimensional changes. Said active element is adapted to be embedded in the body of the tool holder and in such manner that said dimensional changes impart bending to the body of the tool holder.

Abstract: In a handheld power tool, including a first housing part and a second housing part as well as a damping element between the first housing part and the second housing part, the damping element is connectable to the first housing part and the second housing part, and the handheld power tool further has at least one securing element, which is connectable to the first housing part and the second housing part.

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 anti-phase to motion of the hammer piston to counteract vibrations produced by operation of the hammer action of the tool.

Abstract: A handle assembly for a power tool is described and includes a first substantially tubular body portion 210 which contains a first spring 212. A second body portion 216 is slidably mounted within first body portion 210 and contains a second spring 218. A third body portion 222 is also slidably mounted within first body portion 210. The biasing coefficient, or spring constant, of the first spring 212 is less than that of the second spring 218. The first, second and third body portions 210, 216 and 222, and first and second springs, 212 and 218, are all mounted coaxially on threaded bolt 224. In use the third body portion 222 moves within first body portion 210 in a direction towards end portion 214 and the first and softer spring 212 becomes compressed more rapidly than the second and harder spring 218.

Abstract: A power tool has a handle assembly which is biased by a torsional spring. The torsional spring has an engaging arm the position of which is fixed relative to the housing by an adjusting mechanism. The adjusting mechanism has a lever which extends outside the housing of the power tool, and a cam surface, and is mounted on and rotatable at least partially around an axle. In use, the tension in the torsional spring may be adjusted by movement of the lever. The lever is moved, causing rotation of the adjusting cam around the axle. As a result, the cam surface causes the engaging arm of the spring to be moved axially along the axle and more or less tension is applied to the torsional spring.

Abstract: A powered hand tool comprising a pneumatic motor including a cylinder, a main body formed as a hollow tube member, a main body rear end being formed with a fluid inlet and a fluid outlet, said main body being axially disposed for engagement with said pneumatic motor, a main body front end with an interior surface fitted for engagement with a lock nut, said pneumatic motor having a rotary shaft axially extending out of said main body front end wherein the diameter of said pneumatic motor is smaller than the diameter of said hollow tube member, an internal isolation layer composed of a vibration isolation material placed in said hollow tube member so that said vibration isolation material is engaged with and adjacent said ends of said hollow tube member and said pneumatic motor.

Abstract: In a hand power tool, having at least one first housing part for receiving at least one electric motor and at least one second housing part for receiving at least one gear, the electric motor and the gear are connected to one another, and the first housing part and the second housing part are connected, and in the connection region between the first housing part and the second housing part, at least one damping element is provided.

Abstract: An auxiliary handle for a hand-held power tool has a handle part gripped by a hand of an operator and defining an axial direction. An attachment part with which the auxiliary handle is to be attached to a power tool is provided. An elastic damping element connects the handle part and the attachment part, wherein the handle part is secured to the attachment part by positive fit. A unitary holding section is connected to the handle part or the attachment part and a unitary securing section is connected to the attachment part or the handle part. The holding section surrounds with lateral play in all directions the securing section on all sides so that a damping space is generated between the securing section and the holding section. The damping element fills out the damping space at least partially.

Abstract: A percussion hand-held power tool includes a housing (4), a chuck (2) provided at one end of the housing (4), a handle (3) provided at an opposite end of the housing (4) and secured thereto, an axially displaceable percussion mechanism (5) located in the housing and connected thereto, at its handle side, by a spring (6) and a transversely extending articulated arm (7), and supported in the housing (4), at its chuck side, by axial slide surface element (8).

Abstract: A hand-operated power tool has a housing with a drive mechanism for driving a tool, a tool receptacle for receiving a tool, a handle assembly for grasping and handling located in a rear region which is remote from the tool receptacle and engaging the housing, wherein the handle assembly is vibration-damped with respect to the housing with components contained in the housing, at least and substantially in an axial direction.

Abstract: A shock-absorbing structure installed in a pneumatic tool to absorb shocks from the impact unit of the pneumatic tool is disclosed to include a housing, and a shock-absorbing socket, the shock-absorbing socket having a socket body fastened to the impact unit and axially movably mounted in a receiving hole inside the housing, a first spring coil connected between the rear side of the socket body and the housing and alternatively compressed and stretched to absorb shocks upon reciprocating motion of the impact unit, and a second spring coil connected between the front side of the socket body and the housing and alternatively compressed and stretched in direction reversed to the first spring coil upon reciprocating motion of the impact unit.

Abstract: It is an object of the invention to provide an effective technique for reducing the manufacturing costs of a handle mounted to a power tool. According to the invention, a representative handle may comprise a handle body, a grip, an elastic element and an elastic outer surface member. The grip is hollow-shaped and the handle body is inserted into the grip. The elastic element is disposed between the inner surface of the grip and the outer surface of the handle body to apply a biasing force to the grip upon movement of the grip with respect to the handle body when vibration of the power tool is transmitted from the handle body to the grip. The elastic outer surface member covers the outer surface of the grip. The elastic outer surface member is integrally formed with the elastic element. As a result, the manufacturing costs can be reduced compared with known construction in which the elastic outer surface member and the elastic element are separately formed.

Abstract: A portable hand-held power tool (2), especially in the form of a drilling or chisel hammer, includes a drive assembly (8) located in the tool housing (10) for driving a tool spindle (4) along an operational axis (A), a first handle (16) which is rotatable around a first pivotal axis (S1) by a first handle suspension (22), a second handle (20) located on the opposite sides (14.1, 14.2) of the housing which is rotatable around a second pivotal axis (S2) by a second handle suspension (24), and spring elements for retaining the handles (16, 20) in their initial position, with the first and second handle suspensions (22, 24) extending partially circumferentially about the drive assembly (8).

Abstract: It is an object of the present invention to provide a vibration reducing technique caused by air pressure fluctuations within a power tool. According to the present invention, a representative power tool may comprise a driving motor, a driver and a tool bit. The driving motor drives the driver to cyclically reciprocate. The tool bit is linearly driven by utilizing the pressure of air within the power tool. The air may be compressed by the reciprocating movement of the driver. The power tool changes the rotational speed of the driving motor in the cycle of the reciprocating movement of the driver so that vibration caused in the power tool can be alleviated.

Abstract: A power tool is provided including a resilient boot having a radial flange mounted in a seat formed by housing halves in order to provide a sealed barrier segregating air of an inlet vent of a motor from air of an exhaust vent and the boot also mounting the motor and providing vibration dampening between the motor and the housing halves. The boot and housing also include wire management slots and the boot absorbs tolerance stack-up of components and provides shock absorption when the power tool is dropped.

Abstract: A blast-hole drilling rig includes a carriage, a mast disposed on the carriage, and a rotary head mounted on the mast for up-and-down movement. The rotary head includes: a housing forming an internal chamber, a hydraulically driven motor, and a rotation transmission mechanism disposed in the chamber. The rotation transmission mechanism includes a gear system having a high-speed power input section operably connected to the motor, and a low-speed power output section adapted for connection to a drill pipe. The rotation transmission mechanism includes an anti-vibrational inertial body forming part of the high-speed power input section for storing rotational energy to even-out rotary speed variations and resist the generation of vibrations during operation. The inertial body includes a downwardly open recess in which the motor casing extends, wherein the motor projects downwardly past a bottom wall of the housing.

Abstract: An engine breaker includes a vertically extending cylindrical main body (1), a work member (2) supported by a lower portion of the main body for up and down movement, an engine (5) mounted to an upper portion of the main body and having an output shaft arranged to extend horizontally, and a striker (30) incorporated in the main body (1) for successively striking an upper end of the work member (2) through rotation of a horizontally extending rotary shaft (6) to which rotation output of the engine (1) is transmitted. The engine (5) includes a housing (5a) supported by the main body (1) via a resilient member (8), and a flexible coupling (9, 9A, 9B) for absorbing vibration in a direction crossing the rotary shaft (6) is interposed between the output shaft (52) and the rotary shaft (6).

Abstract: A coupling between the handle (2) and the machine housing (1) of a hand power tool having the greatest possible vibration damping is produced by the fact that the handle (2) is coupled with the machine housing (1) via two or more parallel levers (4, 5) situated nearly perpendicular to the longitudinal axis (3) of the hand power tool, whereby the levers (4, 5) are hinge-mounted on the machine housing (1) on the one hand and on the handle (2) on the other hand.

Abstract: It is an object of the invention to provide a technique for further improving the vibration reducing performance in the power tool, while avoiding complicating the construction of the power tool. According to the present invention, a representative power tool may comprise a striker, a tool bit and a vibration reducer. The vibration reducer serves to reduce vibration on the striker by reciprocating in a direction opposite to the reciprocating direction of the striker. The path of the center of gravity of the vibration reducer is arranged to coincide with a path of the center of gravity of the striker. With such construction, because rotating moment is not exerted onto the reciprocating cylinder during the operation of the power tool, vibration reduction can be performed in a stable manner.

Abstract: A method and apparatus for driving and extracting piles that includes a vibration/tension load absorber assembly mounted between a housing and the vibratory unit which includes shear-type vibration absorbers connected between the housing and the vibratory unit and operating in combination with at least one compression-type vibration absorber positioned to be compressed between first and second compression plates when the tension load reaches a predetermined level.

Abstract: A power tool includes vibration isolation material positioned between an engine shroud and a drive shaft housing. The vibration isolation material isolates the drive shaft housing from engine vibration for radial, axial, and torsional movement without utilizing intermediate components.

Abstract: An impact tool enables a front cover part to be easily attached to and detached from a housing body, with a device having a simplified structure. The front cover part has an annular fastening portion clamped to the outer peripheral surface of a front edge portion of the housing body, a cylindrical portion extending from the front end of the housing to the region of the fastening portion, and a connecting portion connecting together the cylindrical portion and the fastening portion. The fastening portion is split at a circumferential part thereof to form a pair of circumferentially opposing tongue-shaped portions. A clamping device is provided between the tongue-shaped portions, which is movable between a clamping position where it pulls the tongue-shaped portions toward each other and an unclamping position where the tongue-shaped portions are released from being pulled toward each other.

Abstract: A tool for a powered machine, having vibration damping member. A method of providing a tool having a vibration damping member arrangement, applicable to different tools, is described. Estimated antinode positions along the tool in use are determined and a vibration damping member arrangement is located to cover at least one selected antinode position.

Abstract: A vibration-decoupling arrangement for supporting a percussion unit (2) in a hand-held percussion power tool includes a spring (4) arranged between the percussion unit (2) and a tool housing (3) and preloaded against an engagement point (P) in the housing (3) for preventing vibrations of the percussion unit (2) from being transmitted to the housing (3), and two axially spaced, flexurally deformable, articulated arms (5a, 5b) secured in the housing (3) for supporting the percussion unit (2) in the housing (3), with the arms (5a, 5b) being secured in the housing (3) with a possibility of a limited axial displacement and without any slip motion relative to the housing.

Abstract: A partially percussive electrical hand tool machine (1) having a portable housing (3), a striking mechanism module (4) connected, in a vibration-damped manner, to the housing (3) and having electrical lines (5) for electrical connection of the relatively moveable striking mechanism module (4) to the housing (3). The electrical lines (5) are non-vibrationally attached in a bending flexible wiring bridge (7) arranged transverse to the striking axis (A).

Abstract: It is, accordingly, an object of the present invention to provide an electric hammer with improved construction, while ensuring the vibration reduction performance. According to the present invention, a representative electric hammer may include a hammer bit, a driving motor, a crank mechanism and a counter weight. The crank mechanism drives a striker by converting a rotating output of the driving motor to linear motion in the axial direction of the hammer bit. The counter weight is detachably mounted to the crank mechanism and serves to reduce vibration of the striker. According to the representative hammer, because the counter weight is detachably mounted to the crank mechanism, it is possible to switch between the mode in which the counter weight is mounted on the hammer body in order to reduce and alleviate vibration and the mode in which the counter weight is removed from the hammer so that the operation can be performed with the hammer having a lighter weight and slimmer appearance.

Abstract: It is an object of the invention to provide a technique for further improving the vibration reducing performance in the power tool, while avoiding complicating the construction of the power tool. According to the present invention, a representative power tool may comprise a striker, a tool bit and a vibration reducer. The vibration reducer serves to reduce vibration on the striker by reciprocating in a direction opposite to the reciprocating direction of the striker. The path of the center of gravity of the vibration reducer is arranged to coincide with a path of the center of gravity of the striker. With such construction, because rotating moment is not exerted onto the reciprocating cylinder during the operation of the power tool, vibration reduction can be performed in a stable manner.

Abstract: An article having a first structure and a second structure. The first structure includes a structural portion and an overmold portion, which is formed from a resilient material and molded onto the structural portion. The overmold portion is configured to perform an auxiliary function, such as creating a seal portion that is configured to sealing engage the second structure, an isolator portion that is configured to contact the second structure and dampen vibrations that are transmitted thereto and/or an auxiliary gripping surface.

Abstract: A vibration damper is disposed between two components (2, 3) of a portable handheld work apparatus (4). The vibration damper is held especially between a housing (6), which holds an internal combustion engine (5), and a handle (7) which is fixed on the housing (6) for guiding the work apparatus (4). The vibration damper includes a coil spring (9) and respective attachment elements (11, 12) at the ends (10, 13) of the coil spring. A coupling member (17) is provided to ensure that the work apparatus can be guided notwithstanding a break of a coil spring. The coupling member (17) projects through the coil spring (9) and bridges the axial distance (16) between the attachment elements (11 and 12). The coupling member (17) is connected to each attachment element (11, 12) so that it cannot separate therefrom.

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 conversion means 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: An assembly for a percussion power tool includes a carrying handle (5) and a flush head (4) which is connected with the power tool chuck (3) for flushing a working tool receivable in the chuck and which has an inlet opening (12) for a flushing fluid and communicating with the working tool stem (2), the carrying handle (5) and the flush head (4) forming a functional unit.

Abstract: A vibration-decoupling arrangement for supporting a percussion unit (2) in a hand-held percussion power tool includes a spring (4) arranged between the percussion unit (2) and a tool housing (3) and preloaded against an engagement point (P) in the housing (3) for preventing vibrations of the percussion unit (2) from being transmitted to the housing (3), and two axially spaced, flexurally deformable, articulated arms (5a, 5b) secured in the housing (3) for supporting the percussion unit (2) in the housing (3), with the arms (5a, 5b) being secured in the housing (3) with a possibility of a limited axial displacement and without any slip motion relative to the housing.

Abstract: A shock-absorbing structure installed in an pneumatic tool to absorb shocks from the impact unit of the pneumatic tool is disclosed to include a housing, and a shock-absorbing socket, the shock-absorbing socket having a socket body fastened to the impact unit and axially movably mounted in a receiving hole inside the housing, a first spring coil connected between the rear side of the socket body and the housing and alternatively compressed and stretched to absorb shocks upon reciprocating motion of the impact unit, and a second spring coil connected between the front side of the socket body and the housing and alternatively compressed and stretched in direction reversed to the first spring coil upon reciprocating motion of the impact unit.

Abstract: A damping apparatus for a reciprocating pneumatic tool mainly includes a cylindrical damper. The damper has a front opening and an enlarged rear end. The front opening is attached to a cylinder of the reciprocating pneumatic tool. A damping segment is formed between the front opening and the enlarged rear end of the damper. A spiral slot is defined longitudinally through the enlarged rear end of the damper. Several slots are defined parallel and transversely in the damping segment of the damper and communicate with the spiral slot. The damping segment has gaps arranged longitudinally by the slots such that the structure has high internal damping to attenuate shock that is caused by return movement of a piston in the cylinder. Consequently, a user holding the pneumatic tool can feel comfortable.

Abstract: A nailing machine includes a nose member disposed in the leading end portion of a main body of the nailing machine for driving the leading nail of stick-shaped connected nails supplied thereto, and a magazine mounted in an opening formed in the side surface of the nose member for sequentially supplying the connected nails to the nose member. When the magazine is fit to the nose member, an elastic member is pressed in into a clearance provided between the nose member and the magazine.

Abstract: A portable power tool includes an internal combustion engine that includes a crankshaft in which a load applied thereto is unevenly distributed along the axis of the crankshaft with respect to the axis of the reciprocating movement of a piston. The portable power tool also includes operational members that are driven by the internal combustion engine, a rotational body fixed to an end of the crankshaft to which a smaller component of the load is applied, and a balancing weight provided on the rotational body for absorbing vibrations generated by the reciprocating movement of the piston. The centroid of the balancing weight is disposed at an angular position from 140 degrees to 180 degrees with respect to the axis of the reciprocating movement of the piston in a rotational direction of the rotational body, when the piston is positioned at a top dead center.

Abstract: A system and method for reducing reaction forces induced in a machine frame by an oscillating tool employs a counterforce assembly which is driven to move along linear slides mounted to the machine frame. The counterforce assembly is driven with a drive signal derived from two signals: a first signal which is proportional to the acceleration of the tool, and a second signal which is directly proportional to the velocity of the oscillating tool. By properly-adjusting the acceleration and velocity components of the drive signal, the magnitude of the reaction forces induced in the machine frame by the oscillating tool can be substantially reduced. The counterforce assembly preferably includes a centering means which prevents it from moving to either end of the slide. An accelerometer is preferably mounted to the machine frame to sense its vibration, with the accelerometer output used to adjust the counterforce assembly's drive electronics to reduce vibration to a minimum.

Abstract: A vibration-isolating member is formed of an elastic material, and has a mounting hole at the center thereof, a large diameter section at an end of the mounting hole, a groove at the periphery of the large diameter section, and a flange. One of a vibration-source-side member and a vibration-receiving member is fitted into each of the large diameter section and the groove. An end opposite from the large diameter section is secured to one of the vibration-receiving member and the vibration-source-side member by a mounting member. Since the inside diameter of the large diameter section is larger than any other part of the mounting hole, either of the vibration-source-side member or the vibration-receiving member and the mounting member can be received. The flange prevents the vibration-isolating member from disengaging from one of the vibration-source-side member and the vibration-receiving member.

Abstract: A percussion rotary hand-held power tool including a percussion piston (3), an anvil (5), a chuck (4) for receiving a working tool, an axially displaceable and rotatable guide tube (6) located in the housing (2) and extending in a telescopic-like manner over the chuck (4) and the anvil (5) from a chuck region up to a region of the percussion piston (3), and a sealing element (8) located between the guide tube (6) and the housing (2) and having at least one axial seal (9) for performing only axial movement and at least one rotary shaft seal (10) for performing only rotary movement.

Abstract: The invention is directed to a portable handheld work apparatus such as a brushcutter, edge cutter or the like. The work apparatus has a drive motor which drives a rotatable work tool via a drive shaft (3) journalled in a guide tube (2). The guide tube (2) is held in a housing (5) of the drive motor by an anti-vibration unit (6). The anti-vibration unit (6) includes a clamp (7) which surrounds the guide tube (2) and elastic damping elements (8, 9) which lie between the clamp (7) and the housing (5). The clamp (7) surrounds the guide tube (2) and is fixed form tight on the housing (5).

Abstract: Readily available steel “I” beams being strengthened sufficiently (without introducing localised stresses that exacerbate the fatigue difficulty) over at risk regions and particularly adjacent the lower regions of the beam that hitherto have given rise to fatigue difficulties. It is therefore to such a strengthened beam for a post driver or any variant thereof machines made using such a beam, their use and to related methods of strengthening such beams of post drivers.

Abstract: The invention concerns a rock drill handle which is connectable to a hand-held rock drill and which includes vibration damping means to damp the transmission of at least back and forth vibrations from the drill to the hand of an operator gripping the handle. In the preferred embodiments, the handle comprises operatively forwardly located connecting means connectable to the backhead of the drill, an operatively rearwardly located handle section and at least one linking section which extends rearwardly from the connecting means to the handle section, the linking section including damping means.

Abstract: A motor housing (11) is mounted in a handle body (10) so as to slide in the longitudinal direction. A tubular pipe (37) that can slide in a bore (38) of the body (10) projects from the back of the housing (11). Compressed air can be applied to the bore (38) through a switching valve (40). A piston (14) with a piston rod (17) can slide in the housing and a tool can be secured to its front end. A flutter valve (23) which alternatingly connects the bore (38) to the two cylinder chambers (27, 28) is built into the valve housing (22). The piston (14) alternatingly opens the connection to an outgoing air conduit (29-31). A pre-stressed spring (47) is set between the body (10) and the housing (11). In operation, the housing (11) oscillates out of step with the piston (14), so that their initial forces are largely compensated and no vibrations are transmitted to the handle body (10).

Abstract: A hand held-type apparatus for fracturing a gate or riser from a casting subsequent to a foundry pouring process. The apparatus operates off of a driven piston assembly, which upon a stroke of such causes a hammer end of the piston assembly to extend from the apparatus and contact the casting, thereby causing the fracturing of the gate or riser from the casting. The apparatus also includes an assembly for decelerating the driven piston assembly upon a stroke of such, as well as an apparatus for isolating the linear motion of the apparatus from the operator thereof.

Abstract: The present invention relates to a device for vibration control in a machine for internal turning, said machine comprising a cutting tool supported by a tool holder, the device comprising a control unit, a vibration sensor connectible to the control unit, and an actuator connectible to the control unit, and the actuator comprising an active element, which converts an A.C. voltage supplied by the control unit to the actuator into dimensional changes. Said active element is adapted to be embedded in the body of the tool holder, and is adapted to be embedded in such manner that said dimensional changes impart bending to the body of the tool holder.

Abstract: This invention relates generally to an impact tool. The present invention provides a vibration isolated impact tool wherein an impact mechanism and a motor assembly are arranged into a cartridge assembly. An elastomeric member resiliently connects the cartridge assembly with a housing. The cartridge assembly is free to move axially and rotationally within the housing. The elastomeric member absorbs axial vibration and torsional vibration, reducing the vibration transmitted to an operator.

Abstract: An arrangement of frictional gripping zones on the handle of a power tool is disclosed. The power tool has a main body portion and a handle portion depending from the main body portion. The handle portion includes a first side region, a second side region opposite the first side region, a rear region connecting the first and second side regions along a rear of the handle portion, and a front region connecting the first and second side regions along a front of the handle portion. A plurality of alternating first and second gripping zones extend longitudinally along each of the first and second side regions of the handle portion. The first gripping zones are made the first gripping zones being made from a first material and the second gripping zones are made from a second material different from the first material. Preferably, the material of the second gripping zones have a hardness greater than the material of the first gripping zones.