POWER TOOL WITH HAMMER MECHANISM

Abstract

A power tool with a hammer mechanism includes a final output shaft configured to hold a tool accessory and defining a drive axis of the tool accessory, a housing, and a handle movable relative to the housing in an axial direction of the drive axis. The housing and the handle are at least partially shaped such that a radial distance between the housing and the handle is shorter when the handle is in a first relative position maximally spaced from the housing in the axial direction than when the handle is in a second relative position close to the housing in the axial direction.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a power tool having a hammer mechanism and configured to linearly drive a tool accessory. STATE OF THE ART

[0002] Impact drills are configured to perform a hammering action for linearly driving a tool accessory mounted in a tool holder along a drive axis and a drilling action for rotating the tool accessory around the drive axis. Generally, a motion conversion mechanism that converts the rotational motion of an intermediate shaft into linear motion is used for the hammering action, and a rotation transmission mechanism that transmits rotation to the tool holder via the intermediate shaft is applied for the drilling action. This type of impact drill is subject to a reaction force from a workpiece against a hammering force of the tool accessory when the hammering action is performed. This reaction force causes vibration mainly in a direction in which the drive axis extends (hereinafter also referred to as an axial direction).This vibration is transmitted to a housing of the hammer drill and thus to a user.

[0003] JP 2022-36606 A and JP 2022-128006 A each disclose a percussion drill having a structure for damping such vibration in the axial direction. Specifically, a handle of the percussion drill is configured to be slidable in the axial direction on guides arranged on a motor housing that houses a motor. The handle is biased away from the motor housing in the axial direction by biasing members. When the tool accessory is subjected to the reaction force according to the hammering operation, this reaction force causes portions other than the handle to move backward relative to the handle against the biasing forces of the biasing members along with the tool accessory. At the same time, the biasing members are elastically deformed, and the reaction force is partially dampened. This damping effect results in a reduction in the axial vibration transmitted to the handle due to the reaction force.

[0004] The impact drill is also subject to vibration in a direction crossing the axial direction due to the driving of the motion conversion mechanism and the motor. The transmission of such vibration to a handle is reduced due to the radial rattling between the handle and the motor housing, provided that a clearance (play, gap) is maintained between the handle and the motor housing. Specifically, the impact drill disclosed in JP 2022-128006 A has elastic members arranged between the handle and the motor housing, and can therefore effectively reduce the transmission of vibration in the direction crossing the axial direction to the handle. SHORT SUMMARY

[0005] However, if the clearance (gap) provided between the handle and the motor housing is large enough to reduce the transmission of vibration in the direction crossing the axial direction to the handle, the radial chatter between the handle and the motor housing will increase when the user holds the impact drill in their hand in a state where the impact drill is not pressed against the workpiece, thereby impairing the feel of using the impact drill. This problem is not limited to impact drills and commonly occurs in other types of power tools with a hammer mechanism and a drive mechanism for performing the hammering action.

[0006] Under these circumstances, it is desirable to provide a power tool having a hammer mechanism with improved feel while reducing vibration in a direction crossing an axial direction.

[0007] The above-mentioned object is achieved by a power tool according to claim 1.

[0008] The present description discloses a power tool with a hammer mechanism.This power tool may include a final output shaft configured to removably hold a tool accessory and defining a drive axis of the tool accessory, a motor, a drive mechanism configured to perform at least one hammering action for linearly driving the tool accessory along the drive axis using power from the motor, a housing, a handle configured to be movable relative to the housing in an axial direction of the drive axis, a biasing member configured to bias the handle away from the final output shaft in the axial direction, and at least one guide member disposed between the housing and the handle to extend in the axial direction and configured to guide the relative movement between the handle and the housing.The housing and the handle may at least partially have a shape such that a radial distance between the housing and the handle is shorter when the handle is in a first relative position that is maximally distant from the housing in the axial direction than when the handle is in a second relative position that is close to the housing in the axial direction.

[0009] According to this power tool with a hammer mechanism, in a state where the power tool (specifically, the tool attachment held by the final output shaft) is not pressed against the workpiece, the handle is in the first relative position, and therefore the radial distance between the housing and the handle (i.e., the clearance) is relatively shortened. Therefore, when the user holds the power tool with his hand in this state, the radial rattle between the handle and the housing is relatively reduced, and the use feeling of the power tool is improved. On the other hand, when the power tool is pressed against the workpiece to machine the workpiece, the handle is in the second relative position, and therefore the radial distance between the housing and the handle is relatively increased.Therefore, the transmission of vibration in the direction crossing the axial direction to the handle can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side view of a hammer drill according to an embodiment with a handle located in an initial position relative to the main body housing. Fig. 2 is a rear view of the hammer drill. Fig. 3 is a vertical cross-sectional view of the impact drill along a line AA shown in Fig. 2, with the handle located in the initial position relative to the main body housing. Fig. 4 is a perspective view of the hammer drill. Fig. 5 is a perspective view of the hammer drill with the handle removed. Fig. 6 is a perspective view of the hammer drill with the handle removed. Fig. Figure 7 is a left side view of the hammer drill with the handle removed. Fig. Fig. 8 is a vertical cross-sectional view of the impact drill along a line BB shown in Fig. 2, with the handle located in the initial position relative to the main body housing. Fig. 9 is a vertical cross-sectional view of the impact drill along the line BB shown in Fig. 2, with the handle located in a closest position relative to the main body housing. Fig. 10 is an enlarged partial view of Fig. 8. Fig. 11 is an enlarged partial view of Fig. 9. Fig. 12 is a side view showing a left half of the handle. Fig. 13 is a rear view of the hammer drill with a portion of components including the handle removed therefrom. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0010] Representative and non-limiting specific examples of the present teachings are explained in detail below with reference to the drawings. This detailed description is merely intended to disclose to those skilled in the art details for implementing preferred embodiments of the present teachings and is not intended to limit the scope of the present invention. Furthermore, additional features and inventions disclosed below may be used separately or in conjunction with the other features or inventions to provide further improved devices, and methods of making and using them.

[0011] Furthermore, combinations of features or methods disclosed in the detailed description below are not required in the practice of the present invention in the broadest sense and are described only to illustrate representative specific examples of the present invention. Furthermore, to provide additional useful embodiments of the present invention, various features of the representative specific examples mentioned above and below, as well as various features described in the independent and dependent claims, need not necessarily be combined as described in the specific examples listed herein or in the order listed.

[0012] Regardless of the configurations of the features described in the embodiments and / or the claims, all features described in the present description and / or the claims are intended to be disclosed individually and independently of one another for the purpose of original disclosure, as well as for limiting the specific subject matter claimed. Furthermore, all numerical ranges and indications of groupings or categories are intended to be disclosed, including all possible intermediate configurations thereof, for the purpose of original disclosure, as well as for limiting the specific subject matter claimed.

[0013] In one or more embodiments, the motor may have a rotation axis extending parallel to the drive axis. The housing may house the motor. The handle may be disposed outside the housing in a radial direction with respect to the rotation axis and may have a first portion extending in the axial direction of the rotation axis and a second portion extending in a direction crossing the first portion so that a user can grip the second portion. At least one guide member may be disposed between the housing and the first portion. According to the power tool configured in this manner, the radial rattling between the handle and the housing can be relatively reduced when the handle is in the first relative position, and the use feel of the power tool is improved.Furthermore, when the handle is in the second relative position, the radial distance between the housing and the handle is relatively increased, and the transmission of the vibration in the direction crossing the axial direction to the handle can be reduced.

[0014] In one or more embodiments, the power tool may include at least one elastic member disposed adjacent to the at least one guide member and between the at least one guide member and the housing, or between the at least one guide member and the handle. According to this configuration, when vibration in the direction crossing the axial direction occurs with the power tool in use, the at least one elastic member is elastically deformed in the direction crossing the axial direction and dampens this vibration. Therefore, the transmission of vibration in the direction crossing the axial direction to the handle can be effectively reduced.

[0015] In one or more embodiments, the housing may include at least one first abutment portion. The handle may include at least one second abutment portion, which abuts with at least one first abutment portion in such a manner that a clearance (distance, space) in the radial direction is zero (i.e., the radial relative displacement is prevented) when the handle is in the first relative position, and is not abutted with the first abutment portion when the handle is in the second relative position. According to this configuration, in the state where the power tool is not pressed against the workpiece, the handle is in the first relative position, and the at least one first abutment portion of the housing and the at least one second abutment portion of the handle are in abutment with each other in such a manner that the radial clearance therebetween becomes zero.Therefore, in the state where the power tool is not pressed against the workpiece, the radial rattling between the handle and the motor housing can be further reduced, and the use feeling of the power tool is further improved.

[0016] In one or more embodiments, the at least one first abutment portion may include at least one first tapered surface extending to be located at a more inner position in the radial direction toward the final output shaft. The at least one second abutment portion may include at least one second tapered surface extending to be located at a more inner position in the radial direction toward the final output shaft and being planarly contactable (in planar / areal contact) with the at least one first tapered surface. According to this configuration, compared with such a configuration in which the at least one first abutment portion and the at least one second abutment portion are each a surface facing in the radial direction (ie,a surface parallel to the axial direction), the at least one first abutment portion and the at least one second abutment portion are instantly separated from each other, thereby creating a clearance (clearance) that allows the handle and the housing to move relative to each other (i.e., a clearance (clearance) that contributes to reducing the transmission of vibration to the handle in the direction crossing the axial direction) when the handle starts to move relative to the housing from the first relative position toward the second relative position (i.e., when the user starts to press the power tool against the workpiece to machine the workpiece). Therefore, the vibration damping performance can be further improved.Furthermore, the at least one first abutment region and the at least one second abutment region can function as a guide when the handle returns from the second relative position to the first relative position.

[0017] In one or more embodiments, the at least one first abutment portion may include at least one first front abutment portion and at least one first rear abutment portion spaced apart from the at least one first front abutment portion in the axial direction and disposed at a position farther from the final output shaft than the at least one first front abutment portion. The at least one second abutment portion may include at least one second front abutment portion configured to abut against the at least one first front abutment portion, and at least one second rear abutment portion spaced apart from the at least one second front abutment portion in the axial direction and configured to abut against the first rear abutment portion.According to this configuration, the at least one first abutment portion and the at least one second abutment portion are in abutment with each other at at least two positions spaced from each other in the axial direction, and therefore, the radial rattling between the handle and the housing can be further stably reduced in the state where the power tool is not pressed against the workpiece (ie, when the handle is in the first relative position).

[0018] In one or more embodiments, the at least one first abutment region may include at least three first abutment regions circumferentially spaced from each other. According to this configuration, the at least one first abutment region and the at least one second abutment region abut each other at at least three positions circumferentially spaced from each other, and therefore, the radial rattling between the handle and the housing can be further stably reduced.

[0019] In one or more embodiments, when a front-to-back direction is defined as a direction in which the drive axis extends, an up-down direction is defined as a direction perpendicular to the front-to-back direction and generally coincident with a direction in which the second portion of the handle extends, and a left-right direction is defined as a direction perpendicular to the front-to-back direction and the up-down direction, the at least one guide member and the at least one first abutment portion may include four sets of guide members and first abutment portions, each arranged in four quadrants defined based on the up-down direction and the left-right direction, with an origin set on the radial axis. According to this configuration, in the state in which the power tool is not pressed against the workpiece (ie,, when the handle is in the first relative position), the at least one first abutment portion and the at least one second abutment portion are each in abutment with each other at four positions distributed in a balanced manner among the four quadrants. Therefore, the radial rattling between the handle and the housing can be further reduced, and the use feel of the power tool is further improved. Furthermore, the guide member is respectively arranged at each of the four positions arranged in a balanced manner with the four quadrants, and therefore the handle can smoothly move slidably relative to the housing in the axial direction. In other words, wobbling (wobbling) of the axial relative movement between the handle and the housing in the direction crossing the axial direction can be reduced.

[0020] In one or more embodiments, the four sets of guide members and the first abutment portions may be arranged such that a circumferential distance (circumferential spacing) between the guide member and the first abutment portion, which are adjacent to each other, is shorter than a circumferential distance between the two guide members that are adjacent to each other. According to this configuration, the circumferential distance between the guide member and the first abutment portion is relatively shortened, and therefore, the radial rattling between the handle and the housing can be further reduced when the handle is removed from the first relative position, and the feel of using the power tool is further improved.

[0021] In one or more embodiments, a separation distance between the at least one second front abutment portion and the at least one second rear abutment portion may be equal to or longer than one-third of a distance over which the guide member extends in the longitudinal direction of the guide member. According to this configuration, the separation distance between the at least one second front abutment portion and the at least one second rear abutment portion in the axial direction can be relatively increased. Therefore, the radial rattle between the handle and the housing can be further stably reduced in the state in which the power tool is not pressed against the workpiece (i.e., when the handle is in the first relative position).

[0022] In one or more embodiments, the housing may include at least one rear abutment portion that is continuous with an edge portion of the at least one first beveled surface of the at least one first rear abutment portion on an opposite side from the final output shaft. The at least one rear abutment portion may be configured to contact the handle to restrict relative displacement between the handle and the housing in the radial direction when the handle is in the second relative position and the handle is displaced relative to the housing in the radial direction by a predetermined amount. According to this configuration, when the handle is displaced relative to the housing by the predetermined amount in the radial direction while the power tool is pressed against the workpiece for machining the workpiece (ie,while the handle is in the second relative position), further displacement is prevented by the at least one rear stop portion. Furthermore, the first rear abutment portion and the at least one rear stop portion can be integrally structured, and therefore the structure of the housing can be simplified.

[0023] In one or more embodiments, the housing may include at least one front-side abutment portion that is continuous with an edge portion of the at least one first beveled surface of the at least one first front-side abutment portion on a side closer to the final output shaft. The at least one front-side abutment portion may be configured to contact the handle to restrict relative displacement between the handle and the housing in the radial direction when the handle is in the second relative position and the handle is displaced relative to the housing in the radial direction by a predetermined amount. According to this configuration, when the handle is displaced relative to the housing by the predetermined amount in the radial direction while the power tool is pressed against the workpiece for machining the workpiece (ie,while the handle is in the second relative position), further displacement is prevented by the at least one front stop portion. Furthermore, the first front abutment portion and the at least one front stop portion can be integrally structured, and therefore the structure of the housing can be simplified.

[0024] In the following description, a percussion drill 10 as an example of a power tool with a hammer mechanism according to an exemplary embodiment will be described in further detail with reference to the drawings. In the present embodiment, the percussion drill 10 is presented as an example of a power tool with a hammer mechanism. The percussion drill 10 is a handheld power tool used for machining work, such as chiseling and drilling, and is designed to perform an operation for linearly driving a tool accessory 11 (see Fig. 3) along a predetermined drive axis AX1 (hereinafter referred to as a hammering operation) and an operation for rotationally driving the tool accessory 11 around the drive axis AX1 (hereinafter referred to as a drilling operation).

[0025] First, the overall configuration of the impact drill 10 is mainly described with reference to Fig. 1 to 3 briefly described. As in Fig. 1, the outer casing of the impact drill 10 mainly includes a main body casing 20 and a handle 30 coupled to the main body casing 20.

[0026] The main body housing 20 is a hollow member that houses a spindle 40, a drive mechanism 50, a motor 60, and the like. The spindle 40 is an elongated hollow cylindrical member and has a tool holder 41 at one axial end portion thereof. The tool holder 41 removably holds the tool accessory 11. The longitudinal axis of the spindle 40 defines the drive axis AX1 of the tool accessory 11. The main body housing 20 extends along the drive axis AX1. The tool holder 41 is arranged at one end portion of the main body housing 20 in an extending direction of the drive axis AX1 (hereinafter simply referred to as an axial direction).

[0027] The handle 30 is arranged on one side of the main body housing 20 in the axial direction (the opposite side from that where the spindle 40 is arranged). The handle 30 has a grip portion 31 extending in a direction intersecting the drive axis AX1 (specifically, in a direction generally perpendicular to the drive axis AX1). The grip portion 31 is a portion intended to be gripped by a user and is formed to protrude in the direction intersecting the drive axis AX1.

[0028] As used in the following description, a front-back direction of the impact drill 10 is defined for convenience as the extending direction of the drive axis AX1 (the direction along the longitudinal axis of the main body case 20). A front side and a back side of the impact drill 10 are respectively defined to be one side in the front-back direction on which the spindle 40 is located and the opposite side (on which the motor 60 is located). Further, an up-down direction of the impact drill 10 is defined to be a direction perpendicular to the drive axis AX1 and generally coincident with the direction in which the handle portion 31 extends. An upper side and a lower side of the impact drill 10 are respectively defined to be one side in the up-down direction on which the main body case 20 is located and the opposite side in the up-down direction.the opposite side to the protruding end of the grip portion 31. Furthermore, a left-right direction of the impact drill 10 is defined to be a direction perpendicular to the front-back direction and the up-down direction. A right side and a left side of the impact drill 10 are defined to be the right side and the opposite side in the left-right direction thereof, respectively, when the front side is viewed from the back.

[0029] Now the detailed configuration of the impact drill 10 is described. As in Fig. As shown in Figure 3, the main body housing 20 includes a gear housing 21 and a motor housing 22. The spindle 40 and the drive mechanism 50 are housed in the gear housing 21.

[0030] The motor 60 is housed in the motor housing 22. The motor housing 22 is disposed adjacent to the rear of the transmission housing 21. The motor housing 22 is a single component and includes a tubular portion 23 and a bearing support portion 24.

[0031] The tubular portion 23 is a tubular portion extending in the axial direction. Specifically, the tubular portion 23 has a front end portion and a rear portion located at the rear of the front end portion. The front end portion of the tubular portion 23 has a circumferential length (i.e., a dimension around the drive axis AX1) approximately equal to the rear end portion of the transmission case 21. The rear portion has an outer diameter smaller than the front end portion of the tubular portion 23. The bearing holding portion 24 protrudes rearward from the rear end surface of the tubular portion 23 and has an outer diameter smaller than the outer diameter of the rear half of the tubular portion 23.

[0032] As in Fig. 3, the motor 60 includes a motor main body portion 61 including a stator and a rotor, and a motor shaft 62 configured to be rotatable integrally with the rotor. The motor main body portion 61 is housed in the tubular portion 23 (specifically, in the rear portion of the tubular portion 23). A rotation axis AX2 of the motor 60 (the motor shaft 62) is located below the drive axis and extends parallel to the drive axis AX1. The motor shaft 62 is rotatably supported by two bearings about the rotation axis AX2. The front end portion of the motor shaft 62 extends to an inside of the gear case 21. A drive pinion 63 is formed on this portion, which projects into the interior of the gear case 21.

[0033] The spindle 40 is a final output shaft of the impact drill 10. As in Fig. As shown in Figure 3, the spindle 40 is arranged in the gear housing 21 along the drive axis AX1 and is supported by two bearings for rotation about the drive axis AX1 relative to the main body housing 20. The spindle 40 is configured as an elongated stepped circular hollow cylindrical member.

[0034] The front half portion of the spindle 40 forms the tool holder 41, in which the tool accessory 11 is removably mountable. The tool accessory 11 is inserted into the front end portion of the tool holder 41 in such a manner that the longitudinal axis of the tool accessory 11 coincides with the drive axis AX1. The tool accessory 11 is held by the tool holder 41 in a state in which it can move axially relative to the tool holder 41 and is restricted from rotating about the axis. The rear half portion of the spindle 40 forms a cylinder 42 that slidably supports a piston 54, which will be described later.

[0035] The drive mechanism 50 is configured to perform the hammering operation for linearly driving the tool accessory 11 along the drive axis AX1 and the drilling operation for rotationally driving the tool accessory 11 about the drive axis AX1 using the power of the motor 60.

[0036] Specifically, the drive mechanism 50 includes a hammer mechanism 51 for the hammering action. The hammer mechanism 51 includes a motion conversion member 52, an arm portion 53, the piston 54, a striking piston 55, and a striking pin 56. The motion conversion member 52 is arranged around an intermediate shaft 57. The intermediate shaft 57 extends parallel to the rotation axis AX2 of the motor shaft 62. The intermediate shaft 57 is rotatably supported by two bearings. A rotational force of the motor shaft 62 is transmitted to the intermediate shaft 57 via a gear 58 that meshes with the drive pinion 63 formed at the front end of the motor shaft 62. The motion conversion member 52 is configured to reciprocate in the front-to-back direction in conjunction with the rotation of the intermediate shaft 57. The arm portion 53 operably connects the motion conversion member 52 and the piston 54.The rotary motion of the intermediate shaft 57 is converted into a linear motion of the motion converting member 52 and is transmitted to the piston 54 via the arm portion 53.

[0037] The piston 54 is a cylindrical component with a bottom and is arranged in the cylinder 42 of the spindle 40 so as to be slidable along the drive axis AX1. The impact piston 55 is arranged in the piston 54 so as to be slidable along the drive axis AX1. An internal space at the rear of the impact piston 55 in the piston 54 is defined as an air chamber that serves as an air spring. The firing pin 56 is an intermediate element that transmits kinetic energy of the impact piston 55 to the tool accessory 11. The firing pin 56 is arranged in the tool holder 41 at the front of the impact piston 55 so as to be movable along the drive axis AX1.

[0038] When the rotational motion of the intermediate shaft 57 is converted into linear motion and transmitted to the piston 54 as described above, the piston 54 moves in the front-to-back direction. At the same time, the air pressure in the air chamber changes, and the impact piston 55 slides in the front-to-back direction within the piston 54 under the action of the air spring. Specifically, as the piston 54 moves forward, the air in the air chamber is compressed, and the internal pressure increases. The impact piston 55 is pushed forward at a high speed under the action of the air spring and strikes the impact pin 56. The impact pin 56 transmits the kinetic energy of the impact piston 55 to the tool accessory 11. Consequently, the tool accessory 11 is driven linearly along the drive axis AX1. On the other hand, as the piston 54 moves backward, the air in the air chamber expands, and the internal pressure decreases.As a result, the impact piston 55 is pulled backward. The tool accessory 11 moves backward along with the impact pin 56, being pressed against the workpiece. In this way, the hammering action is repeated by the hammer mechanism 51.

[0039] Furthermore, the drive mechanism 50 includes a rotation transmission mechanism for the drilling operation. The rotation transmission mechanism includes a drive gear 59 and is configured to transmit the rotational motion of the intermediate shaft 57 to the spindle 40 for rotationally driving the tool accessory 11 about the drive axis AX1. Specifically, the drive gear 59 is fixed to the front end portion of the intermediate shaft 57. A driven gear 43, which is fixed to the outer periphery of the cylinder 42 of the spindle 40, meshes with the drive gear 59. Due to this, the spindle 40 rotates integrally with the driven gear 43 in conjunction with the drive gear 59, which rotates integrally with the intermediate shaft 57. This results in the execution of the drilling operation for rotationally driving the tool accessory 11, held by the tool holder 41, about the drive axis AX1.

[0040] In the present embodiment, the impact drill 10 has three selectively executable operation modes, namely a hammer and drilling mode, a hammer mode, and a drilling mode. The hammer and drilling mode is an operation mode for executing the hammering operation and the drilling operation by driving both the hammer mechanism 51 and the rotation transmission mechanism. The hammer mode is an operation mode for executing only the hammering operation by blocking the power transmission for the drilling operation and driving only the hammer mechanism 51. The drilling mode is an operation mode for executing only the drilling operation by blocking the power transmission of the hammering operation and driving only the rotation transmission mechanism. These operation modes are switched in response to operation of a mode switching dial 12. Such an operation mode switching mechanism is known, and therefore, the description thereof is omitted herein.

[0041] The drive mechanism 50 described above is disclosed, for example, in US 2015 / 144366 A1 and US 2016 / 136801 A1. The disclosures of US 2015 / 144366 A1 and US 2016 / 136801 A1 are incorporated herein by reference in their entirety.

[0042] As in Fig. 1 to 3, the handle 30 includes the grip portion 31 and a tubular portion 32. The tubular portion 32 is a tubular portion extending in the front-to-back direction. As shown in Fig. As shown in Figure 2, the tubular portion 32 is disposed outside the motor housing 22 in the radial direction with respect to the rotation axis AX so as to circumferentially surround the motor housing 22. The grip portion 31 is an elongated hollow body extending from the rear end of the tubular portion 32 in the direction crossing the rotation axis AX2. In the present embodiment, the tubular portion 32 and the front portion of the grip portion 31 are integrally formed. The handle 30 is formed by screwing together left and right halves.

[0043] A power cord 13, which is connectable to an external AC power source, extends from the lower end of the handle portion 31. A trigger 14 is attached to the handle portion 31. The trigger 14 is intended to receive a pushing operation performed by the user. A switch 15 is disposed in the handle portion 31. The switch 15 is placed in an ON state in response to the pushing operation performed on the trigger 14. When the switch 15 is placed in the ON state, the impact drill 10 causes the motor 60 to be energized (energized) to drive the drive mechanism 50, thereby performing the hammering action and / or the drilling action.

[0044] In the present embodiment, the main body housing 20 and the handle 30 are coupled via an expandable and compressible bellows 25. Specifically, the bellows 25 is formed in a ring shape so as to circumferentially surround the rotation axis AX2, as shown in Fig. 4 and Fig. 5. The front edge of the bellows 25 is connected to the motor housing 22, and the rear edge of the bellows 25 is connected to the tubular portion 32 of the handle 30. According to the bellows 25, dust can be prevented from entering the interior of the hammer drill 10 via a gap between the main body housing 20 and the handle 30.

[0045] In the present embodiment, the impact drill 10 is configured to reduce the transmission of vibration to the handle 30 that occurs when the motor 60 and the drive mechanism 50 are driven. In the following description, a vibration damping structure of the impact drill 10 will be described.

[0046] As the vibration damping structure, the main body housing 20 and the handle 30 are configured to be relatively movable in the front-to-back direction. This relative movement is slidably guided by four guide members 70 that are arranged between the main body housing 20 (specifically, the motor housing 22) and the handle 30 (specifically, the tubular portion 32) and extend in the front-to-back direction. In the present embodiment, the guide members 70 are mounted to the motor housing 22 (specifically, the tubular portion 23) via elastic members 71. Specifically, as shown in Fig. As shown in FIGS. 5 to 7, the elastic members 71 are fixed to the tubular portion 23 of the motor housing 22, and the guide members 70 are further fixed to the elastic members 71 (i.e., to the surfaces of the elastic members 71 opposite to the tubular portion 23). In the present embodiment, an adhesive is used for the fixation between the elastic members 71, the guide members 70, and the tubular portion 23. However, any fixing method may be used instead of the adhesive.

[0047] The handle 30 slides on the guide members 70 when the main body housing 20 and the handle 30 move relatively in the front-to-back direction. Specifically, the handle 30 has flat (level, smooth) sliding surfaces 325 inside the handle 30, as shown in Fig. 12. The flat sliding surfaces 325 are aligned parallel to the radially outer surfaces of the guide members 70. The relative movement between the main body housing 20 and the handle 30 in the front-to-back direction is realized due to the sliding movement of these flat sliding surfaces 325 on the guide members 70. The guide members 70 extend longitudinally in the front-to-back direction, and their longitudinal direction coincides with the front-to-back direction. As shown in Fig. As shown in Fig. 7, the guide members 70 extend approximately the entire length of the tubular portion 23 in the front-to-back direction. A stable sliding movement between the main body case 20 and the handle 30 can be achieved by ensuring as long a length of the guide members 70 as possible in this manner. The guide members 70 are made of metal in the present embodiment, but may be formed of another material (such as hard synthetic resin). Furthermore, each of the guide members 70 is in the form of a metal sheet (metal plate), but each of the guide members 70 may be formed in another shape (e.g., in the form of a pin that is circular in cross section).

[0048] The elastic members 71 in the present embodiment are sponges, that is, synthetic resin foam (e.g., polyurethane). However, the elastic members 71 are not limited to sponges and may be any elastic member elastically deformable in a direction crossing the front-to-back direction (hereinafter also referred to as a crossing direction). For example, the elastic members 71 may be formed of a flexible synthetic resin such as silicone resin or urethane. The elastic members 71 are arranged between the guide members 70 and the motor housing 22 (the tubular portion 23) in a non-compressed state. Therefore, the elastic members 71 can be elastically deformed (pressed) in the radial direction with respect to the rotational axis AX2 of the motor shaft 62 when subjected to a force in the direction crossing the rotational axis AX2.In an alternative embodiment, the elastic members 71 may be arranged in a slightly compressed state by being pushed radially through the handle 30 (the tubular portion 32).

[0049] As in Fig. 5, Fig. 6 and Fig. As shown in Figure 13, the four sets of guide members 70 and elastic members 71 are arranged such that they are spaced apart from each other in the circumferential direction with respect to the rotation axis AX2. Thus, the circumferentially distributed arrangement of the guide members 70 enables the impact drill 10 to have even smoother slidability and reduces the wobbling (wobbling) of the handle 30 from the rotation axis AX2 at the time of sliding movement.

[0050] In the configuration in which the handle 30 is movable relative to the main body housing 20 in the front-to-back direction in this manner, the handle 30 is constantly biased rearward (ie, away from the spindle 40 in the front-to-back direction). Specifically, the impact drill 10 has three bias springs 16, as shown in Fig. 5 to 7. In the present embodiment, the biasing springs 16 are in the form of coil springs and are arranged in a compressed state between the tubular portion 23 and the tubular portion 32. The three biasing springs 16 are arranged at equal intervals in the circumferential direction with respect to the rotation axis AX2. Therefore, the biasing springs 16 can evenly bias the handle 30 in a plane perpendicular to the rotation axis AX2.

[0051] Due to such a configuration, the impact drill 10 allows the handle 30 to move relative to the main body housing 20 in the front-back direction between an initial position located in Fig. 1, Fig. 3 and Fig. 8 and a nearest position shown in Fig. 9. The initial position is a relative position of the handle 30 in a state where the main body case 20 and the handle 30 are not subjected to any force in the front-to-back direction (that is, in a state where the tool accessory 11 held by the spindle 40 is not pressed against the workpiece). In the initial position, the handle 30 is located at a position farthest away from the main body case 20 (the motor case 22) in the front-to-back direction (that is, a position maximally away (spaced) from the main body case 20). The closest position is a relative position of the handle 30 in a state where a rearward force is applied to the main body case 20 and the main body case 20 and the handle 30 are closest to each other in the front-to-back direction.Each of the initial position and the nearest position is defined by an abutment between abutment areas (not shown) formed on the motor housing 22 and the handle 30, respectively.

[0052] According to the impact drill 10 described above, when the tool accessory 11 is subjected to a backward reaction force during the hammering operation, the spindle 40 that holds the tool accessory 11 and the main body housing 20 that supports the drive mechanism 50 are also subjected to the backward reaction force. Due to this, the handle 30 can move relative to the main body housing 20 between the initial position and the closest position. In other words, the handle 30 moves relative to the spindle 40 in the front-to-back direction against the biasing forces of the biasing springs 16, while the main body housing 20 and the handle 30 are slidably guided by the guide members 70. Part of the reaction force is dampened by the elastic deformation of the biasing springs 16 at this time.This damping effect reduces the transmission of vibration in the front-to-back direction to the handle 30, which occurs due to the reaction force.

[0053] Furthermore, according to the impact drill 10, when vibration occurs in the cross direction due to the driving of the motion conversion member 52 and the motor 60, the elastic members 71 disposed between the motor housing 22 and the tubular portion 32 of the handle 30 are elastically deformed in this vibration direction to dampen this vibration. Therefore, the transmission to the handle 30 with respect to the vibration in the cross direction is also reduced. Furthermore, in the present embodiment, sponges having an easily elastically deformable property are used as the elastic members 71. This can ensure that the elastic members 71 are elastically deformed by a large amount in the cross direction. Consequently, the effect of reducing the transmission to the handle 30 with respect to the vibration in the cross direction is improved.

[0054] Furthermore, the elastic members 71 are arranged at four positions distributed along the circumferential direction, and the elastic members 71 located at circumferentially different positions are elastically deformed in directions different from each other. Therefore, the effect of reducing the transmission to the handle 30 of vibration in the crossing direction is improved.

[0055] The impact drill 10 has a configuration that can ensure that the impact drill 10 has an excellent feel while achieving the effect of reducing the transmission of vibration in the cross direction to the handle 30. The following description describes such a configuration.

[0056] As in Fig. As shown in FIGS. 5 to 7, the tubular portion 23 of the motor housing 22 has four sets of first front abutment portions 231, first rear abutment portions 232, front stopper portions 233, and rear stopper portions 234 on the outer surface thereof. These four sets are each arranged to be spaced apart in the circumferential direction with respect to the rotation axis AX2. In each of the sets, the first front abutment portion 231, the first rear abutment portion 232, the front stopper portion 233, and the rear stopper portion 234 are arranged to be linearly aligned in the front-to-rear direction.

[0057] How best in Fig. As shown in Fig. 11, in the present embodiment, each of the first front-side abutment portion 231 and the first rear-side abutment portion 232 is in the shape of a chamfered (tapered, inclined) surface that approaches the rotation axis AX2 toward the front (i.e., toward the spindle 40). In other words, the chamfered surface extends to be located toward the front on a radially inner side. In the present embodiment, the front-side abutment portion 233 is a flat surface portion continuous with the front edge portion of the front-side abutment portion 231. Further, in the present embodiment, the rear-side abutment portion 234 is a flat surface portion continuous with the rear edge portion of the first rear-side abutment portion 232.

[0058] As in Fig. 11 and Fig. 12, the tubular portion 32 of the handle 30 has four sets of second front abutment portions 321, second rear abutment portions 322, front recessed portions 323 and rear recessed portions 324 inside the tubular portion 32 (only two sets on the left side are shown in Fig. 12). These four sets are arranged such that they are spaced apart in the circumferential direction with respect to the rotation axis AX2. The circumferential positions of the four sets of the second front abutment portions 321, the second rear abutment portions 322, the front recessed portions 323, and the rear recessed portions 324 are respectively aligned with the circumferential positions of the four sets of the first front abutment portions 231, the first rear abutment portions 232, the front stop portions 233, and the rear stop portions 234. The second front abutment portion 321, the second rear abutment portion 322, the front recessed portion 323, and the rear recessed portion 324 are arranged such that they are linearly aligned in the front-to-back direction in each of the sets on the tubular portion 32.

[0059] How best in Fig. As seen in Fig. 11, in the present embodiment, each of the second front-side abutment portion 321 and the second rear-side abutment portion 322 is in the shape of a tapered surface that approaches the rotation axis AX2 toward the front (i.e., toward the spindle 40). In other words, the tapered surface extends to be located toward the front on a radially inner side. The inclination angles of the second front-side abutment portion 321 and the second rear-side abutment portion 322 in the tapered surface shape are respectively equal to the inclination angles of the first front-side abutment portion 321 and the first rear-side abutment portion 322 in the tapered surface shape. The front-side recessed portion 323 is a flat surface continuous with the rear edge portion of the second front-side abutment portion 321 in the tapered surface shape.The rear recessed portion 324 is a flat surface continuous with the rear edge portion of the second rear abutment portion 322 in the shape of the beveled surface.

[0060] As in Fig. 8 and Fig. As shown in Figure 10, the four first front abutment portions 231 and the four second front abutment portions 321 are in abutment with each other when the handle 30 is in the initial position relative to the main body case 20. In this state, the radial clearance (distance) between the first front abutment portions 231 and the second front abutment portions 321 is zero. Similarly, the four first rear abutment portions 232 and the four second rear abutment portions 322 are in abutment with each other (i.e., the beveled surfaces are in planar contact with each other). In this state, the radial clearance (distance) between the first rear abutment portions 232 and the second rear abutment portions 322 is zero.

[0061] In such a state, the handle 30 cannot be displaced radially relative to the main body housing 20. Therefore, when the user holds the impact drill 10 with his hand in this state, the impact drill 10 can be prevented from rattling radially between the handle 30 and the main body housing 20. Consequently, the feel of using the impact drill 10 can be improved.

[0062] Specifically, in the present embodiment, the abutment state is formed (established) at two positions spaced apart in the front-rear direction, and therefore, radial rattle can be further stably reduced. However, the abutment state can be formed at only one position. In other words, one of the combination of the first front-side abutment portion 231 and the second front-side abutment portion 321 and the combination of the first rear-side abutment portion 232 and the second rear-side abutment portion 322 can be omitted.

[0063] Furthermore, in the present embodiment, the abutment state is formed at four circumferentially spaced positions, and therefore, radial rattle can be further stably reduced. However, the shapes of the motor housing 22 and the tubular portion 32 can be changed such that the abutment state is formed at only one position, two positions, or three positions, or the abutment region is formed at five or more positions. Radial rattle can be significantly reduced by forming the abutment state at at least three or more positions.

[0064] On the other hand, when the tool accessory 11 is pressed against the workpiece for machining the workpiece by the impact drill 10, the handle 30 begins to move relative to the main body housing 20 from the initial position toward the nearest position. This causes, for example, the four first front abutment portions 231 and the four second front abutment portions 321 to be spaced apart from each other, thereby enabling the handle 30 to be radially displaced relative to the main body housing 20, as shown in Fig. 9 and Fig. 11. Accordingly, when vibration occurs in the cross direction (the direction crossing the front-to-back direction), the elastic members 71 are elastically deformed in the direction crossing the front-to-back direction as described above, thereby reducing the transmission of vibration in the cross direction to the handle 30.

[0065] Furthermore, in the present embodiment, when the handle 30 is radially displaced relative to the main body case 20 by a predetermined amount in the state where the tool accessory 11 is pressed against the workpiece, the front stopper portions 233 and the flat sliding surfaces 325 of the handle 30 are brought into planar contact with each other, and the rear stopper portions 234 and the rear recessed portions 324 are also brought into planar contact with each other. Due to this, further radial relative displacement between the handle 30 and the main body case 20 is restricted. According to this configuration, radial relative displacement between the handle 30 and the main body case 20 can be restricted before a limit of elastic deformation of the elastic members 71 is reached.Therefore, the impact drill 10 can be prevented from excessively rattling radially between the handle 30 and the main body case 20. Consequently, the feel of using the impact drill 10 can be improved.

[0066] In the present embodiment, the abutment state described above is formed by means of the tapered surfaces. Therefore, when the handle 30 begins to move relative to the main body case 20 from the initial position toward the closest position (that is, when the user begins to press the tool accessory 11 against the workpiece to machine the workpiece), the four first front abutment portions 231 and the four second front abutment portions 321 are immediately separated from each other, thereby generating clearances that allow the handle 30 and the main body case 20 to move radially relative to each other (clearances that provide the above-described vibration damping effect). Therefore, the vibration damping property can be improved.Furthermore, the first front abutment portions 231 and the four second front abutment portions 321 in the shape of the beveled surface can function as guides when the handle 30 returns to the initial position.

[0067] In the present embodiment, the planar contact is formed at two positions spaced apart in the front-to-rear direction, and therefore, the radial rattle can be further stably reduced. However, the planar contact may be formed at only one position. Alternatively, the shapes of the motor housing 22 and the tubular portion 32 may be changed in such a way that the planar contact is formed at three or more positions. Furthermore, the shapes of the motor housing 22 and the tubular portion 32 may be changed to bring the motor housing 22 and the tubular portion 32 into linear contact or point contact with each other instead of the planar contact.

[0068] Furthermore, in the present embodiment, the planar contact is formed at four circumferentially spaced positions, and therefore, radial rattle can be further stably reduced. However, the shapes of the motor housing 22 and the tubular portion 32 can be changed such that the planar contact is formed at only one position, two positions, or three positions, or the planar contact is formed at five or more positions. Radial rattle can be significantly reduced by forming the planar contact at at least three or more positions.

[0069] Furthermore, in the present embodiment, the first rear abutment portions 232 and the rear stopper portions 234 have an integral continuous structure, and therefore, the shape of the tubular portion 23 can be simplified. Similarly, the first front abutment portions 231 and the front stopper portions 233 have an integral continuous structure, and therefore, the shape of the tubular portion 23 can be simplified. However, the first rear abutment portions 232 and the rear stopper portions 234 may be spaced apart from each other. Similarly, the first front abutment portions 231 and the front stopper portions 233 may be spaced apart from each other.

[0070] If four quadrants 91 to 94 are specified, which are defined based on the up-down direction and the left-right direction, with an origin set on the rotation axis AX2, as shown in Fig. 13, the sets of guide members 70 and abutment portions (first front abutment portions 231 and first rear abutment portions 232) are arranged in quadrants 91 to 94, respectively, as shown in Fig. 5 to 7 and 13. Therefore, in the state where the tool accessory 11 is not pressed against the workpiece (that is, when the handle 30 is in the initial position), the first front abutment portions 231 and the first rear abutment portions 232 and the second front abutment portions 321 and the second rear abutment portions 322 are respectively in abutment with each other at four positions distributed in a balanced manner among the four quadrants 91 to 94. Therefore, the radial chatter between the handle 30 and the motor housing 22 can be further reduced, and the use feel of the impact drill 10 is further improved.Furthermore, in the present embodiment, the guide members 70 and the first abutment portions (the first front abutment portions 231 and the first rear abutment portions 232) are arranged in such a manner that the distances between the guide members 70 and the first abutment portions adjacent to each other are each shorter than the distances between the two guide members 70 adjacent to each other. According to this configuration, the distances between the guide members 70 and the first abutment portions are relatively shortened, and therefore, the radial rattle between the handle 30 and the motor housing 22 can be further reduced when the handle 30 is removed from the first relative position, and the feel of using the hammer drill 10 can be further improved.

[0071] Furthermore, the sets of the stopper portions (the front stopper portions 233 and the rear stopper portions 234) and the elastic members 71 are arranged in the quadrants 91 to 94, respectively, as shown in Fig. 5 to 7 and 13. Thus, the four sets of stopper portions and elastic members 71 are arranged in such a manner that, in the circumferential direction with respect to the rotation axis AX2, the distances between the front stopper portions 233 and the elastic members 71 that are adjacent to each other and the distances between the rear stopper portions 234 and the elastic members 71 that are adjacent to each other are each shorter than the distances between the two front stopper portions 233 that are adjacent to each other and the rear stopper portions 234 that are adjacent to each other.Therefore, the distances between the elastic members 71 and the stopper portions 233 and 234 (these stopper portions restrict the relative radial displacement between the handle 30 and the main body case 20) are relatively shortened, and this makes it easier to restrict the radial elastic deformation amounts of the elastic members 71. Furthermore, the elastic members 71 and the stopper portions 233 and 234 are each arranged at four positions distributed in a balanced manner among the four quadrants 91 to 94, and this allows the handle 30 to be displaced relative to the main body case 20 with a constant displacement amount, regardless of the radial direction in which the handle 30 is displaced.Therefore, the radial chatter between the handle 30 and the motor housing 20 can be further reduced when the tool accessory 11 is pressed against the workpiece to machine the workpiece, and the use feeling of the impact drill 10 is further improved.

[0072] Furthermore, in the present embodiment, a separation distance L2 between the first front-side abutting portion 231 and the first rear-side abutting portion 232 is set to 1 / 3 or more of a distance L1 by which the guide member 70 extends in the front-rear direction, as shown in Fig.7. Therefore, the separation distance between the first front abutment portion 231 and the first rear abutment portion 232 in the front-to-rear direction can be relatively increased. Therefore, the radial rattle between the handle 30 and the motor housing 22 can be further stably reduced in the state where the tool accessory 11 is not pressed against the workpiece (ie, when the handle 30 is in the initial position).

[0073] The corresponding relationship between each component in the above-described embodiment and each component of the present teachings will be described below. However, each component of the embodiment is merely an example and is not intended to limit every component of the present teachings and the present invention. The impact drill 10 is an example of a "power tool with a hammer mechanism." The tool accessory 11 is an example of a "tool accessory." The spindle 40 is an example of a "final output shaft." The drive axis AX1 is an example of a "drive axis." The motor 60 is an example of a "motor." The rotation axis AX2 is an example of a "rotation axis." The drive mechanism 50 is an example of a "drive mechanism." The motor housing 22 is an example of a "housing." The handle 30 is an example of a "handle." The tubular portion 32 is an example of a "first portion."The grip portion 31 is an example of a "second portion." The biasing spring 16 is an example of a "biasing member." The guide member 70 is an example of "at least one guide member." The elastic member 71 is an example of "at least one elastic member." The first front abutment portion 231 and the first rear abutment portion 232 are an example of "at least one first abutment portion." The second front abutment portion 321 and the second rear abutment portion 322 are an example of "at least one second abutment portion." The first front abutment portion 231 is an example of a "first front abutment portion." The first rear abutment portion 232 is an example of a "first rear abutment portion." The second front abutment portion 321 is an example of a "second front abutment portion."The second rear abutment area 322 is an example of a "second rear abutment area." The front stop area 233 and the rear stop area 234 are an example of a "stop area." The front stop area 233 is an example of a "front stop area." The rear stop area 234 is an example of a "rear stop area." The initial position is an example of a "first relative position." Any position between the initial position and the nearest position and the nearest position are an example of a "second relative position."

[0074] Having described various embodiments of the present invention, the above-described embodiments are intended only to facilitate understanding of the present invention and are not intended to limit the present invention thereto. The present invention may be modified or improved without departing from the scope thereof, and includes equivalents thereof. Furthermore, each of the features described in the claims and the specification may be arbitrarily combined or omitted in any way within a range that allows them to remain capable of achieving at least part of the above-described objects or producing at least part of the above-described advantageous effects.

[0075] For example, the guide members 70 and the elastic members 71 may be fixed to the handle 30 instead of the motor housing 22. According to this configuration, the elastic members 71 are fixed to the inner surface of the handle 30, and the guide members 70 are fixed to the elastic members 71 in such a manner that the elastic members 71 are located between the handle 30 and the guide members 70. Furthermore, the motor housing 22 slides on the guide members 70.

[0076] Alternatively, the elastic members 71 may be omitted. In this case, the guide members 70 may be directly fixed to the motor housing 22 or the handle 30. This configuration can also reduce the transmission of vibration in the direction crossing the axial direction to the handle 30 due to the clearances between the main body housing 20 and the handle 30.

[0077] Alternatively, the motor housing 22 (specifically, the tubular portion 23) and the handle 30 (specifically, the tubular portion 32) may be modified into any shape that at least partially has a shape such that the radial distance between the motor housing 22 (the tubular portion 23) and the handle 30 (the tubular portion 32) is shorter when the handle 30 is in the initial position than when the handle 30 is in a relative position at the front of the initial position. Such a modification also makes it possible to relatively shorten the radial distance between the motor housing 22 and the handle 30 in the state where the tool accessory 11 is not pressed against the workpiece.Therefore, when the user holds the impact drill 10 with his hand in this state, the radial chatter between the handle 30 and the main body case 20 is relatively reduced, and the use feeling of the impact drill 10 is improved.

[0078] Alternatively, the numbers of the guide members 70 and the elastic members 71 can be set to any number. For example, the guide members 70 and the elastic members 71 can be arranged at three positions distributed along the circumferential direction similar to the bias springs 16.

[0079] In the above-described embodiment, the relative movement between the main body casing 20 and the handle 30 and the above-described vibration damping structure are realized by disposing the guide members 70, the first front abutment portions 231, the first rear abutment portions 232, the front stop portions 233, and the rear stop portions 234 on the motor casing 22. However, these components may be disposed at any portion of the main body casing according to the configuration of the impact drill (e.g., the configuration of the components corresponding to the drive mechanism 50 and the motor 60). For example, these components may be disposed on the casing housing the drive mechanism or the casing housing the drive mechanism and the motor, instead of on the motor casing 22 housing the motor 60.

[0080] In the above-described embodiment, the impact drill 10, which performs the hammering action and the drilling action, was described as an example of the power tool with a hammer mechanism. However, the power tool may be an electric hammer that can only perform the hammering action.

[0081] It is explicitly emphasized that all features disclosed in the description and / or the claims are to be considered separate and independent of each other for the purpose of the original disclosure as well as for the purpose of limiting the claimed invention, regardless of the feature combinations in the embodiments and / or the claims. It is explicitly stated that all range specifications or specifications of groups of units disclose every possible intermediate value or subgroup of units for the purpose of the original disclosure as well as for the purpose of limiting the claimed invention, in particular also as a limit of a range specification. LIST OF REFERENCE SYMBOLS

[0082] 10: Impact drill, 11: Tool accessories, 12: Mode switching dial, 13: Power cable, 14: Trigger, 15: Switch, 16: Preload spring, 20: Main body case, 21: Gear case, 22: Motor case, 23: Tubular section, 24: Bearing holding section, 25: Bellows, 30: Handle, 31: Grip section, 32: Tubular section, 40: Spindle, 41: Tool holder, 42: Cylinder, 43: Output gear, 50: Drive mechanism, 51: Hammer mechanism, 52: Motion conversion component, 53: Arm section, 54: Piston, 55: Impact piston, 56: Impact pin, 57: Intermediate shaft, 58: Gear, 59: Drive gear, 60: Motor, 61: Motor main body section, 62: Motor shaft, 63: Drive pinion, 70: Guide member, 71: Elastic member, 91 to 94: Quadrant, 231: First front abutment section, 232: First rear abutment section, 233: Front stop section, 234: Rear stop section, 321: Second front abutment section, 322: Second rear abutment section,223: front recessed area, 324: rear recessed area, 325: flat sliding surface, AX1: drive axis, AX2: rotation axis, QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2022 - 36 606 A

[0003] JP 2022 - 128 006 A [0003, 0004] US 2015 / 144 366 A1

[0041] US 2016 / 136 801 A1

[0041]

Claims

[1] Power tool with a hammer mechanism, with a final output shaft configured to removably hold a tool accessory and defining a drive axis of the tool accessory, an engine, a drive mechanism configured to perform at least one hammering operation for linearly driving the tool accessory along the drive axis using a power of the motor, a housing, a handle configured to be movable relative to the housing in an axial direction of the drive axis, a biasing member configured to bias the handle away from the final output shaft in the axial direction, and at least one guide member arranged between the housing and the handle so as to extend in the axial direction and configured to slidably guide a relative movement between the handle and the housing, wherein the housing and the handle at least partially have a shape such that a radial distance between the housing and the handle is shorter when the handle is in a first relative position that is maximally spaced from the housing in the axial direction than when the handle is in a second relative position that is close to the housing in the axial direction. [2] Power tool according to claim 1, wherein the motor has a rotational axis extending parallel to the drive axis, the housing houses the motor, the handle is arranged outside the housing in a radial direction with respect to the rotation axis and has a first portion extending in the axial direction of the rotation axis and a second portion extending in a direction crossing the first portion so that a user can grip the second portion, and the at least one guide component is arranged between the housing and the first region. [3] Power tool according to claim 1 or 2, further comprising at least one elastic member arranged adjacent to the at least one guide member and between the at least one guide member and the housing or between the at least one guide member and the handle. [4] A power tool according to any one of claims 1 to 3, wherein the housing has at least one first abutment portion, and the handle has at least one second abutment portion which is in abutment with the at least one first abutment portion in such a manner that a distance in the radial direction is zero when the handle is in the first relative position, and is out of abutment with the first abutment portion when the handle is in the second relative position. [5] The power tool according to claim 4, wherein the at least one first abutment portion includes at least one first tapered surface extending to be located at a further inner position in the radial direction toward the final output shaft, and the at least one second abutment portion includes at least one second tapered surface extending to be located at a further inner position in the radial direction toward the final output shaft, wherein the at least one second tapered surface can be brought into planar contact with the at least one first tapered surface. [6] The power tool according to claim 4 or 5, wherein the at least one first abutment portion includes at least one first front abutment portion and at least one first rear abutment portion spaced apart from the at least one first front abutment portion in the axial direction and disposed at a position farther from the final output shaft than the at least one first front abutment portion, and the at least one second abutment portion includes at least one second front abutment portion configured to be in abutment with the at least one first front abutment portion and at least one second rear abutment portion spaced apart from the at least one second front abutment portion in the axial direction and configured to be in abutment with the first rear abutment portion. [7] Power tool according to one of claims 4 to 6, wherein the at least one first abutment region has at least three first abutment regions circumferentially spaced from one another. [8] A power tool according to any one of claims 4 to 7 when dependent on claim 2, wherein, when a front-to-back direction is defined as a direction in which the drive axis extends, an up-down direction is defined as a direction perpendicular to the front-to-back direction and generally coincident with a direction in which the second portion of the handle extends, and a left-right direction is defined as a direction perpendicular to the front-to-back direction and the up-down direction, the at least one guide member and the at least one first abutment portion comprise four sets of guide members and first abutment portions each arranged in four quadrants defined based on the up-down direction and the left-right direction with an origin placed on the rotation axis. [9] A power tool according to claim 8, wherein the four sets of the guide members and the first abutment portions are arranged in such a manner that a circumferential distance between the guide member and the first abutment portion which are adjacent to each other is shorter than a circumferential distance between the two guide members which are adjacent to each other. [10] A power tool according to claim 6 or any one of claims 7 to 9 when dependent on claim 6, wherein a separation distance between the at least one second front abutment portion and the at least one second rear abutment portion is equal to or longer than one third of a distance by which the guide member extends in the longitudinal direction of the guide member. [11] A power tool according to claim 6 when dependent on claim 5, or according to any one of claims 7 to 10 when dependent on claim 5 or 6, wherein the housing has at least one rear abutment portion continuous with an edge portion of the at least one first tapered surface of the at least one first rear abutment portion on an opposite side from the final output shaft, and the at least one rear abutment portion is configured to come into contact with the handle to restrict relative displacement between the handle and the housing in the radial direction when the handle is in the second relative position and the handle is displaced relative to the housing in the radial direction by a predetermined amount. [12] A power tool according to claim 6 when dependent on claim 5, or according to any one of claims 7 to 11 when dependent on claim 5 or 6, wherein the housing has at least one front abutment portion continuous with an edge portion of the at least one first tapered surface of the at least one first front abutment portion on a side closer to the final output shaft, and the at least one front abutment portion is configured to come into contact with the handle to restrict relative displacement between the handle and the housing in the radial direction when the handle is in the second relative position and the handle is displaced relative to the housing in the radial direction by a predetermined amount.

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