JP2008119755A - Impact tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide effective technology for preventing unforeseen switching motion while maintaining operability of a trigger locking switch in an impact tool with the trigger locking switch. <P>SOLUTION: This impact tool 101 has a motor 111, a working tool main body 103, a tool bit 119, a grip 109, a connecting region 109b to connect a rear part of the working tool main body and an upper part of the grip to each other and a trigger 131 to be moved to a motor driving position to electrify and drive the motor by drawing operation by a worker and to be returned to a motor stopping position to stop electrifying and driving of the motor when the drawing operation is released. Further, it has the trigger locking switch 151 arranged on an upper surface or both of left and right side surfaces of the connecting region 109b. The trigger locking switch 151 is constituted to be operated in a direction along an outer surface of the connecting region 109b and switched between a trigger locked position to lock the trigger 131 at the motor driving position and a trigger unlocked position to unlock the trigger 131. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an impact tool for performing a machining operation such as a hammer operation or a keren operation on a workpiece by performing an impact operation of a tool bit in a long axis direction.

An impact tool capable of performing a hammering operation on a workpiece is disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-62756 (Patent Document 1). In the impact tool described in Patent Document 1, a tool bit, a motor for driving the tool bit, a power switch for turning on / off the motor, a trigger for operating the power switch, and an operation mode of the tool bit are set. A mode switching member for switching is provided. And it is set as the structure which can be switched by the mode switching member to the hammer mode which makes a tool bit perform only a striking operation, and the hammer drill mode which makes a tool bit perform a striking operation and a rotation operation. In addition, when the mode switching member is switched to the hammer mode, the trigger pulled by the operator is locked at the motor drive position where the power switch is turned on (so-called lock-on), and the trigger pulling operation is released. Is also provided with a lock-on mechanism (hereinafter referred to as a trigger lock switch) that can maintain the locked state of the trigger.
The trigger lock switch described in the publication has a locking member that locks the trigger at the motor drive position by locking with the trigger that is pulled to the motor drive position that turns on the power switch. The locking member is disposed on a side surface of the grip connecting portion that extends horizontally from the rear end portion of the housing toward the rear grip. The locking member penetrates both the left and right side surfaces of the grip connecting portion and extends in the horizontal direction intersecting the tool bit major axis direction, and each end portion in the extending direction protrudes from the side surface of the grip connecting portion. Then, the locking member is moved to the trigger lock position for locking the trigger by pressing one protruding end with a finger, and moved to the trigger lock releasing position for unlocking the trigger by pressing the other protruding part. It is the composition which is done.

In the case of the trigger lock switch described in the publication, since the locking member penetrates the left and right side surfaces of the grip connecting portion, it is assumed that the locking member is operated with the same hand as the hand holding the grip and pulling the trigger. In this case, since it can be operated with either the right hand or the left hand, it has an advantage of good operability. By the way, when a hammer drill is placed on the ground or the like at a work site, for example, the side surface of the housing is usually placed in a stable position such that the side surface contacts the ground. For this reason, in the case of the trigger lock switch described in the publication in which the locking member penetrates the housing and protrudes from the left and right side surfaces and the through direction is the switching operation direction, the locking member is locked when the hammer drill is placed on the ground. There is a possibility that the protruding portion of the member is pushed on the ground and the locking member is switched unexpectedly, and there is still room for improvement in this respect.
JP 2001-62756 A

  In view of this point, an object of the present invention is to provide a technique effective in preventing an unexpected switching operation while maintaining the operability of a trigger lock switch in an impact tool having a trigger lock switch.

In order to achieve the above object, the invention described in each claim is configured.
According to the first aspect of the present invention, a motor, a work tool main body that houses the motor, a tool bit that is attached to the tip region of the work tool main body and that is driven by the motor to perform a striking operation in the long axis direction; A grip disposed on the rear side of the work tool opposite to the tool bit and extending in a direction crossing the long axis direction of the tool bit, and a rear portion and a grip extending in the long axis direction of the tool bit. Motor connected to the upper part of the motor and disposed in the grip, moved to a motor drive position for energizing and driving the motor by a pulling operation by an operator, and stopping the energization driving of the motor when the pulling operation is released A striking tool having a trigger returned to the stop position. The “striking tool” in the present invention typically corresponds to an electric hammer that performs hammering operations such as crushing and crushing on a work material, or an electric cutting device that performs keren operations such as grooving and peeling. However, a wide range of power tools are included that allow the tool bit to perform a striking motion in the long axis direction.

  As a characteristic configuration, the present invention includes a trigger lock switch arranged on the upper surface of the connection region or both the left and right side surfaces. The trigger lock switch is configured to be switched between a trigger lock position that is operated in a direction along the outer surface of the connection region and locks the trigger to the motor drive position, and a trigger lock release position that unlocks the trigger. The “direction along the outer surface” in the present invention means the same direction as the major axis direction of the tool bit, that is, the longitudinal direction of the impact tool, or the direction intersecting the major axis direction of the tool bit, that is, the vertical direction of the impact tool. This is the case. In the present invention, the “trigger lock position and trigger lock release position” are arranged along the outer surface of the articulated region. The trigger lock switch is preferably disposed within a range where a finger (thumb or index finger) holding the grip can reach to enable operation with a finger that operates the trigger by holding the grip. In this invention, it is set as the structure which arrange | positions a trigger lock switch on the upper surface of a connection area | region, or both the left and right side surfaces. That is, since it is arranged symmetrically with respect to the axial center line of the impact tool, it is possible to operate with a finger that grips the grip regardless of the dominant hand of the operator.

  According to the present invention, the trigger lock switch for locking the trigger operated to the motor drive position to the motor drive position operated to be pulled is provided. The trigger lock switch is arranged on the upper surface of the connection region or both the left and right side surfaces, and the operation direction thereof is set in a direction along the outer surface of the connection region. For this reason, for example, at the work site, when the impact tool is placed on the ground or the like in a stable posture, the trigger lock switch comes into contact with the ground if the trigger lock switch is disposed on the upper surface of the connection region. If the trigger lock switch is arranged on the side surface of the connection area, even if the trigger lock switch contacts the ground, the direction of the force acting from the ground is the operation direction of the trigger lock switch. This is a crossing direction, so the trigger lock switch is not activated. That is, according to the present invention, it is possible to prevent the trigger lock switch from being switched unexpectedly.

(Invention of Claim 2)
According to the second aspect of the present invention, the operation direction of the trigger lock switch in the impact tool according to the first aspect is set to be the same direction as the trigger pulling operation direction. That is, the trigger lock switch is slidably disposed along the same direction as the trigger pulling operation direction on the outer surface of the connection region. Thus, by setting the operation direction of the trigger lock switch in the same direction as the pulling operation direction of the trigger, the trigger and the trigger lock switch can be operated by moving the finger in the same direction, so that the operation is easy.

(Invention of Claim 3)
According to the third aspect of the present invention, the trigger lock switch in the impact tool according to the first or second aspect includes a switching operation member that is switched between a trigger lock position and a trigger lock release position, and a trigger. And a locking member that rotates toward the front surface in the return direction of the trigger that has been pulled and locks to the front surface when the pulling operation is performed to the motor drive position. When the trigger is switched to the trigger lock position when the trigger is pulled to the motor drive position, the switching operation member comes into contact with the locking member from the direction intersecting the operation direction of the switching operation member. Accordingly, even when the operator releases the trigger pulling operation, the locking state with respect to the front surface portion of the locking member is maintained. The “rotation toward the front surface” in the present invention typically means a mode in which the switching operation member is pushed and rotated by the switching operation member when the switching operation member is switched to the trigger lock position. Although applicable, the locking member may be rotated by its own weight in accordance with the pulling operation to the motor driving position of the trigger.

  According to the present invention, the switching operation member that has been switched to the trigger lock position is configured to abut on the locking member from a direction that intersects the operation direction of the switching operation member. Therefore, the return force due to the spring or the like added to the trigger hardly acts as a force for moving the switching operation member toward the trigger lock release position. Rather, the force that maintains the switching operation member in the trigger lock position, that is, the switching operation member can act as a force that presses the switching operation member against the member that guides the switching operation of the switching operation member in a direction that intersects the operation direction. It becomes. For this reason, even if an operator releases the pulling operation of the trigger, the locked state of the trigger can be secured by maintaining the locked state of the locking member with respect to the front surface portion of the trigger.

  According to the present invention, in an impact tool having a trigger lock switch, a technique effective in preventing unexpected switching operation while maintaining the operability of the trigger lock switch is provided.

(First embodiment of the present invention)
Hereinafter, the first embodiment of the present invention will be described in detail with reference to FIGS. This embodiment will be described using an electric hammer as an example of an impact tool. FIG. 1 shows the overall configuration of the electric hammer according to the present embodiment, and FIGS. 2 to 7 show the configuration of a lock-on mechanism that locks the trigger in the operated position. As shown in FIG. 1, the electric hammer 101 generally includes a main body portion 103 that forms an outline of the electric hammer 101, and a hollow tool holder 137 in a tip region (left side in the drawing) of the main body portion 103. The main body is composed of a hammer bit 119 that is detachably attached to the main body 103 and a hand grip 109 that is gripped by an operator connected to the opposite side of the hammer bit 119 of the main body 103. The hammer bit 119 is held by the tool holder 137 so that the linear movement in the major axis direction is possible and the relative rotation in the circumferential direction is restricted. The main body 103 corresponds to the “work tool main body” in the present invention, the hammer bit 119 corresponds to the “tool bit” in the present invention, and the hand grip 109 corresponds to the “grip” in the present invention. For convenience of explanation, the hammer bit 119 side is referred to as the front, and the hand grip 109 side is referred to as the rear.

  The main body 103 includes a motor housing 105 that houses the drive motor 111 and a crank housing 107 that houses the motion conversion mechanism 113 and the striking element 115. The drive motor 111 corresponds to the “motor” in the present invention. The rotational output of the drive motor 111 is appropriately converted into a linear motion by the motion conversion mechanism 113 and then transmitted to the striking element 115, and the major axis direction of the hammer bit 119 (the left-right direction in FIG. 1) via the striking element 115. Generates an impact force on. The handgrip 109 is provided with a trigger 131 for turning on / off a power switch 133 (see FIGS. 3 and 4) for energization driving to the drive motor 111.

  The motion conversion mechanism 113 is mainly composed of a drive gear 121, a driven gear 123, a crankshaft 122, a crank plate 125, a crank arm 127, and a piston 129 as a driver, which are driven to rotate in a horizontal plane by a drive motor 111. The crank shaft 122, the crank plate 125, the crank arm 127 and the piston 129 constitute a crank mechanism. The piston 129 is slidably disposed in the cylinder 141 and performs a linear motion along the cylinder 141 as the drive motor 111 is driven to energize.

  The striking element 115 is slidably disposed on the striker 143 slidably disposed on the bore inner wall of the cylinder 141 and the tool holder 137, and transmits the kinetic energy of the striker 143 to the hammer bit 119. And an impact bolt 145 as an intermediate element. The striker 143 is driven via an air spring in the air chamber 141a of the cylinder 141 in accordance with the sliding movement of the piston 129, and collides (hits) with an impact bolt 145 slidably disposed on the tool holder 137. The striking force is transmitted to the hammer bit 119 via the bolt 145.

  The electric hammer 101 configured as described above has a motion conversion mechanism mainly composed of a crank mechanism when the power switch 133 is turned on by the pulling operation of the trigger 131 by the operator and the drive motor 111 is energized. The piston 129 is slid linearly along the cylinder 141 through the cylinder 113, and the striker 143 moves in the cylinder 141 due to the air pressure change in the air chamber 141a of the cylinder 141, that is, the action of the air spring. Move linearly. The striker 143 collides with the impact bolt 145 to transmit the kinetic energy to the hammer bit 119. Thus, the hammer bit 119 performs a hammering operation in the axial direction and performs a hammering operation on the workpiece (concrete).

  As shown in FIGS. 3 and 4, the trigger 131 has a lower side attached to the grip main body 109a of the handgrip 109 so as to be rotatable in the front-rear direction via a support shaft 109d. 133 is moved to the switch-on position for turning on 133, and the power switch 133 is returned to the switch-off position (initial position) for turning off the power switch 133 when the pulling operation is released. The switch-on position corresponds to the “motor drive position” in the present invention, and the switch-off position corresponds to the “motor stop position” in the present invention. The trigger 131 is returned to the switch-off position by a return spring (not shown) for convenience or a return spring to the off position of the power switch 133.

  Next, in the case where the hammer operation is performed continuously, the trigger 131 that has been pulled by the operator can be locked in the switch-on position even when the finger is released from the trigger 131. A description will be given with reference to FIGS. The lock-on mechanism 151 corresponds to the “trigger lock switch” in the present invention. The handgrip 109 includes a grip main body 109a extending in the vertical direction intersecting the major axis direction of the hammer bit 119, and upper and lower connected to the rear side portion of the main body 103 at the upper and lower ends of the grip main body 109a. Connecting portions 109b and 109c (see FIG. 1). The connecting portion 109b on the upper side corresponds to the “connecting region” in the present invention. The handgrip 109 is divided into two parts that are divided into left and right along the long axis direction of the hammer bit 119, and are joined by bolts 109f.

  The upper connecting portion 109b of the hand grip 109 extends in the longitudinal direction of the hammer bit 119, and the lock-on mechanism 151 according to the present embodiment is disposed on the upper surface of the connecting portion 109b (see FIG. 2). ). As shown in FIGS. 3 to 5, the lock-on mechanism 151 mainly includes a switch holder 153, a lock-on button 155, and a lock-on lever 157. The lock-on button 155 corresponds to the “switching operation member” in the present invention, and the lock-on lever 157 corresponds to the “locking member” in the present invention. The switch holder 153 is housed and fixed in an internal space that opens upward in the connecting portion 109b. The lock-on button 155 and the lock-on lever 157 are assembled to the switch holder 153 to form a lock-on assembly. The lock-on button 155 is attached to the switch holder 153 so as to be slidable in the longitudinal direction of the hammer bit 119, that is, in the front-rear direction along the surface direction of the outer surface of the connecting portion 109b. It is possible to move between a lock-on position (position shown in FIG. 4) where the lock can be locked and a lock-on release position (position shown in FIG. 3) where the lock can be released. The lock-on position corresponds to the “trigger lock position” in the present invention, and the lock-on release position corresponds to the “trigger lock release position” in the present invention. The operation direction of the lock-on button 155 arranged as described above is the same as the operation direction of the trigger 131.

  As shown in FIGS. 3 and 4, the lock-on button 155 has a generally plate-like flat surface portion 155 a that extends horizontally, and a protruding knob portion 155 b formed on the upper surface side of the flat surface portion 155 a. As shown in FIG. 2, the knob portion 155b is arranged in the upper surface opening 109g of the connecting portion 109b so as not to protrude from the upper surface of the connecting portion 109b, and the operator inserts his / her finger into the upper surface opening 109g to move back and forth. It can be configured to slide. The lock-on button 155 has a circular shaft portion 155c between the flat surface portion 155a and the knob portion 155b. The shaft portion 155c is slidably engaged with a guide groove 153a extending in the long axis direction of the hammer bit 119 provided in the switch holder 153, thereby stabilizing and smoothing the sliding operation of the lock-on button 155. It is illustrated. Further, the guide groove 153a defines the movement range of the lock-on button 155. That is, when the lock-on button 155 is slid forward or backward by the operator, the shaft portion 155c comes into contact with the front end portion 153b or the rear end portion 153c of the guide groove 153a, whereby the lock-on button 155 is It is positioned at the lock-on position or the lock-on release position. That is, the lock-on position and the lock-on release position of the lock-on button 155 are arranged along the upper surface of the connecting portion 109b.

  The lock-on lever 157 is disposed on the lower surface side of the flat portion 155a of the lock-on button 155, and is supported by the switch holder 153 so as to be rotatable in the vertical direction with the shaft portion 157a as a fulcrum. The lock-on lever 157 faces the upper end surface of the trigger 131 through an opening 109e formed in the lower surface of the connecting portion 109b, and a notch 131a provided at the front upper portion of the trigger 131 and the opposed portion. A locking claw 157b that can be engaged and disengaged is provided. The lock-on lever 157 is held at a position where the tip of the locking claw 157b is in contact with the upper end surface of the trigger 131 when the trigger 131 is in the switch-off position (see FIGS. 3 and 5).

FIG. 7 shows the operation of the lock-on mechanism 151. FIG. 7A shows an initial state. FIG. 7B shows a state where the trigger 131 is pulled by the operator. In this pulled state, when the lock-on button 155 is slid toward the front lock-on position, the lock-on lever 157 pushes the upper surface 157c of the lock-on button 155 as shown in FIG. It is pushed by the flat surface portion 155a and rotates downward about the shaft portion 157a. Then, the locking claw 157b of the lock-on lever 157 is locked to the notch 131a of the trigger 131, whereby the trigger 131 is in the lock-on state. Thus, since the trigger 131 is locked at the switch-on position, the operator does not need to keep pulling the trigger 131 to the operation position, and the hammer work by the hammer bit 119 can be performed easily and continuously. This state is also shown in FIG.
FIG. 7D shows a state where the lock-on button 155 is slid toward the rear lock-on release position. In this state, the flat portion 155a of the lock-on button 155 is separated from the upper surface 157c of the lock-on lever 157, and the rotation restriction of the lock-on lever 157 is released. That is, the lock on of the trigger 131 is released. Then, the pulling operation of the trigger 131 by the operator is released, and the lock-on lever 157 is pushed by the notch 131a of the trigger 131 and rotated upward by the return operation of the trigger 131 to the switch-off position. Allow return to off position. This state is shown in FIG.

  The lock-on mechanism 151 has a position holding mechanism 161 that holds the lock-on button 155 at the position where the lock-on button 155 is switched. As shown in FIGS. 2 and 3, the position holding mechanism 161 includes a steel ball 163, a cross-section arc-shaped groove 165a for the lock-on position into which the steel ball 163 can be fitted, and a cross-section for the lock-on release position. The arc-shaped groove 165b and a coil spring 167 that urges the steel ball 163 toward the grooves 165a and 165b are mainly configured. The grooves 165a and 165b are provided in the switch holder 153. The steel ball 163 is provided on the lock-on button 155 via a coil spring 167. When the lock-on button 155 is switched between the lock-on position and the lock-on release position by the operator, the steel ball 163 is inserted into the lock-on position groove 165a and the lock-on release position groove 165b. Selectively engaged. As a result, the lock-on button 155 is prevented from floating due to vibration generated in the electric hammer 101 during the hammering operation.

  The electric hammer 101 according to the present embodiment is configured as described above. In this embodiment, a lock-on mechanism 151 is disposed on the upper surface of the upper connecting portion 109b of the hand grip 109. For this reason, the operator can operate the lock-on button 155 using the finger (thumb or index finger) holding the hand grip 109 regardless of the dominant hand. That is, in the electric hammer 101 of this embodiment, the pulling operation of the trigger 131 and the operation of the lock-on mechanism 151 can be performed with one hand. In order to enable such a one-hand operation, the lock-on mechanism 151 can be operated. Is placed in an upper position as close to the trigger 131 as possible. This provides a lock-on mechanism 151 with good operability. Further, when the electric hammer 101 is placed in a stable sideways posture on the ground of the work site or the like, the lock-on button 155 disposed on the upper surface of the connecting portion 109b does not contact the ground. For this reason, the unexpected switch of the lock-on button 155 can be prevented.

  Further, in the present embodiment, by setting the operation direction of the lock-on button 155 to the same direction as the operation direction of the trigger 131, that is, the front-rear direction, the trigger 131 and the lock-on button 155 can be operated by moving each finger in the same direction. Thus, the lock-on button 155 is easily operated. In addition, in the present embodiment, in order to ensure the lock-on state of the trigger 131, it intersects with the front-rear direction, which is the operation direction of the lock-on button 155, between the trigger 131 and the lock-on button 155. A lock-on lever 157 that operates in the vertical direction is arranged. Then, in a state where the locking claw 157b provided on the lock-on lever 157 is pulled and locked to the notch 131a of the trigger 131 placed at the switch-on position, the upward pivoting operation that is the unlocking direction of the locking is performed. Is controlled by the flat portion 155a of the lock-on button 155.

  That is, according to the present embodiment, the lock-on lever 157 is brought into contact with the trigger 131 from the direction that intersects the operation direction of the lock-on button 155 with respect to the lock-on lever 157. It is set as the structure to hold. For this reason, the return force due to the spring or the like added to the trigger 131 is less likely to act as a force in the direction of moving the lock-on button 155 toward the trigger lock release position, but rather presses the lock-on button 155 against the switch holder 153. This makes it possible to act as a force for maintaining the switch-on position. As described above, according to the present embodiment, by adjusting the operation direction of the lock-on button 155 to the operation direction of the trigger 131, vibration during hammering operation is maintained while maintaining good operability of the lock-on button 155. Regardless of this, the lock-on state of the trigger 131 can be reliably maintained.

  Further, in the present embodiment, the knob portion 155b is disposed in the upper surface opening 109g of the connecting portion 109b so as not to protrude from the upper surface of the connecting portion 109b. For this reason, for example, during the hammering operation by the electric hammer 101, the operation of switching the lock-on button 155 caused by the interference can be prevented by avoiding that the knob portion 155b interferes with another object.

  By the way, in the electric hammer 101, the main body 103 and the handgrip 109 are manufactured separately, and then assembled together. In the present embodiment, the connecting portion 109 b that connects the main body portion 103 and the hand grip 109 is provided on the hand grip 109. For this reason, the assembly of the trigger 131 and the lock-on mechanism 151 is concentrated on one member, that is, the hand grip 109, and the assemblability can be improved. In addition, the lock-on mechanism 151 in the present embodiment is configured to be a lock-on assembly by assembling the lock-on button 155 and the lock-on lever 157 to the switch holder 153, and therefore can be easily assembled to the connecting portion 109b. .

(Second embodiment of the present invention)
Next, an electric hammer 101 according to a second embodiment of the present invention will be described with reference to FIGS. This embodiment is a modification of the lock-on mechanism 151 described in the first embodiment, and is configured in the same manner as the first embodiment described above except for the lock-on mechanism 151. For this reason, the same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. As shown in FIGS. 8 and 9, the lock-on mechanism 171 according to the present embodiment is disposed on the side surface of the connecting portion 109 b on the upper side of the hand grip 109. The lock-on mechanism 171 corresponds to the “trigger lock switch” in the present invention. As in the first embodiment described above, the lock-on mechanism 171 is configured as a lock-on assembly in which a lock-on button 175 and a lock-on lever 177 are assembled to the switch holder 173, as shown in FIGS. The The lock-on button 175 corresponds to the “switching operation member” in the present invention, and the lock-on lever 177 corresponds to the “locking member” in the present invention.

  The switch holder 173 is disposed in the internal space of the connecting portion 109b so as to penetrate the internal space in the left-right direction (the horizontal direction intersecting the long axis direction of the hammer bit 119). The lock-on button 175 is slidably attached to the switch holder 173 in the longitudinal direction of the hammer bit 119, that is, in the front-rear direction along the surface direction of the outer surface of the connecting portion 109b. It is possible to move between a lock-on position (position shown in FIG. 11) where the lock can be locked and a lock-on release position (position shown in FIG. 10) where the lock can be released.

  The lock-on button 175 has a generally plate-like flat surface portion 175a extending horizontally in the left-right direction, and protruding left and right knob portions 175b formed at the extending end portions of the flat surface portion 175a. As shown in FIG. 12, the left and right knobs 175b protrude laterally from the left and right side surfaces of the connecting portion 109b. Further, a protrusion piece 173b is provided at the front end portion of the switch holder 173 so as to protrude from the side surface of the connecting portion 109b to the side. The protruding amount of the knob 175b is set so as not to protrude sideways beyond a straight line connecting the end surface of the protruding piece 173b and the side surface of the grip body 109a. The lock-on button 175 has a circular shaft portion 175c between the flat surface portion 175a and the knob portion 175b. As shown in FIG. 13, the shaft portion 175c is slidably engaged with a guide groove 173a extending in the long axis direction of the hammer bit 119 provided in the switch holder 173, whereby the sliding operation of the lock-on button 175 is performed. Stabilization and facilitation are achieved. The guide groove 173a defines the movement range of the lock-on button 175. That is, when the lock-on button 175 is slid forward or backward by the operator, the shaft portion 175c comes into contact with the front end portion 173c or the rear end portion 173d of the guide groove 173a. It is positioned at the lock-on position or the lock-on release position. In other words, the lock-on position and the lock-on release position of the lock-on button 175 are arranged along the side surface of the connecting portion 109b.

  The lock-on lever 177 is disposed on the lower surface side of the flat portion 175a of the lock-on button 175, and is supported by the switch holder 173 so as to be rotatable in the vertical direction with the shaft portion 177a as a fulcrum. The lock-on lever 177 has a locking claw 177b that can be engaged with and disengaged from the notch 131a of the trigger 131 through the opening 109e on the lower surface side of the connecting portion 109b. When the trigger 131 is in the switch-off position, the tip of the locking claw 177b is held at a position where it abuts on the upper surface of the trigger 131.

  The lock-on mechanism 171 according to the present embodiment is configured as described above. Therefore, when the operator pulls the trigger 131 to the switch-on position with fingers, the lock-on lever 177 moves the upper surface 177c of the knob 175b of the lock-on button 175 toward the front lock-on position. The lock-on button 175 is pushed by the flat surface portion 175a and rotates downward about the shaft portion 177a. Then, the locking claw 177b of the lock-on lever 177 is locked to the notch 131a of the trigger 131, whereby the trigger 131 is locked on. Thus, since the trigger 131 is locked at the switch-on position, the operator does not need to keep pulling the trigger 131 to the operation position, and the hammer work by the hammer bit 119 can be performed easily and continuously.

  The lock-on mechanism 171 includes a position holding mechanism unit 181 that holds the lock-on button 175 at the position where the switch-on button 175 is switched. As shown in FIGS. 10 and 11, the position holding mechanism portion 181 has a groove portion 185a for the lock-on position, a groove portion 185b having a circular arc shape for the lock-on release position, and a resilient shape with respect to the groove portions 185a and 185b. And a leaf spring 187 having a hemispherical protrusion 183 that engages with the main body. The grooves 185a and 185b are provided in the switch holder 173. The leaf spring 187 is provided on the lock-on button 175. When the operator switches the lock-on button 175 between the lock-on position and the lock-on release position, the leaf spring 187 is moved relative to the groove part 185a for the lock-on position and the groove part 185b for the lock-on release position. The protrusion 183 is selectively engaged. Accordingly, the lock-on button 175 is held at the position where the switching operation is performed, and the lock-on button 175 is prevented from floating due to vibration generated in the electric hammer 101 during the hammering operation.

  The lock-on mechanism 171 according to the second embodiment configured as described above can obtain the same operational effects as the lock-on mechanism 151 of the first embodiment described above. That is, the lock-on mechanism 171 is arranged on both the left and right side surfaces of the upper connecting portion 109 b of the hand grip 109. That is, the lock-on button 175 of the lock-on mechanism 171 is arranged symmetrically with respect to the axial center line of the electric hammer 101. For this reason, the operator can operate the lock-on button 175 using the finger (thumb or forefinger) of the hand holding the handgrip 109 regardless of the dominant hand.

  Further, when the electric hammer 101 is placed in a stable posture on the ground or the like on the work site, the protruding amount from the side surface of the connecting portion 109b of the knob portion 175b of the lock-on button 175 is such that the side surface of the grip body 109a and the switch holder 173 are protruded. Since it is set so as to be inside the straight line connecting the end face of the protruding piece 173b, it is possible to prevent the knob 175b from contacting the ground and prevent the trigger lock button 175 from being unexpectedly switched. In this case, even if the projecting piece 173b is pressed from the ground side, the pressing direction is a direction that intersects with the operation direction of the lock-on button 175, so that the lock-on button 175 is prevented from being switched.

  Further, in the lock-on state in which the trigger 131 is locked at the switch-on position, the lock-on button 175 is in contact with the upper surface 177c of the lock-on lever 177 from the direction intersecting the operation direction of the lock-on button 175. The locked state of the locking claw 177b of the lock-on lever 177 with respect to the notch 131a of 131 is maintained. For this reason, it is possible to reliably maintain the lock-on state of the trigger 131 regardless of the vibration during the hammering operation while adopting a configuration in which the operation direction of the lock-on button 175 is matched with the operation direction of the trigger 131.

In view of the gist of the present invention, the following modes can be configured.
(Aspect 1)
“A striking tool according to claim 3,
The switching operation member is disposed on the upper surface of the connection region and has a knob that is operated by an operator, and the knob is placed in an opening formed on the upper surface of the connection region. A striking tool characterized in that protrusion from the head is suppressed. "
According to the first aspect of the invention, it is possible to rationally prevent the knob from interfering with other objects during the machining operation by the impact tool.

(Aspect 2)
“A striking tool according to claim 3,
The switching operation member is disposed on both the left and right side surfaces of the connection region, and has a knob that protrudes from the side surface of the connection region at a predetermined protruding height and is operated by an operator. Is provided with a protruding piece having a protruding height at least equal to the protruding height of the knob protruding from the side surface, thereby placing the impact tool on the ground or the like in a lying state, An impact tool characterized in that the knob is configured to prevent contact with the ground or the like. "
According to the invention described in the aspect 2, the effect of preventing the unexpected switching of the switching operation member can be further enhanced.

(Aspect 3)
"A striking tool according to any one of claims 1 to 3 or aspects 1 and 2,
The hitting tool, wherein the connecting region is formed in the grip. "
According to the invention described in the aspect 3, after the trigger and the trigger lock switch are assembled to the grip, the grip can be assembled to the work tool main body. For this reason, the assembly property of the trigger and the trigger lock switch is improved.

It is a sectional side view showing the whole electric hammer composition concerning an embodiment of the present invention. It is a perspective view which shows the hand grip which has the lock on mechanism which concerns on 1st Embodiment. It is sectional drawing which shows a trigger and a lock on mechanism, and shows the initial state which the lock on of the trigger was cancelled | released. It is sectional drawing which shows a trigger and a lock on mechanism, and shows the lock on state of a trigger. FIG. 5 is a cross-sectional view showing a trigger and a lock-on mechanism cut at a portion different from those in FIGS. 3 and 4. It is the VI-VI sectional view taken on the line in FIG. It is explanatory drawing which shows operation | movement of a lock on mechanism in steps. It is a side view of a hand grip which has a lock on mechanism concerning a 2nd embodiment. It is a front view of a hand grip similarly. It is sectional drawing which shows a trigger and a lock on mechanism, and shows the initial state which the lock on of the trigger was cancelled | released. It is sectional drawing which shows a trigger and a lock on mechanism, and shows the lock on state of a trigger. It is the XII-XII sectional view taken on the line in FIG. It is the XIII-XIII sectional view taken on the line in FIG.

Explanation of symbols

101 Electric hammer (blow tool)
103 Main body (work tool main body)
105 Motor housing 107 Crank housing 109 Hand grip 109a Connecting portion on grip body 109b (connecting region)
109c Lower connecting portion 109d Support shaft 109e Opening portion 109f Bolt 109g Upper surface opening portion 111 Drive motor (motor)
113 Motion conversion mechanism 115 Impact element 119 Hammer bit (tool bit)
121 driving gear 122 crankshaft 123 driven gear 125 crank plate 127 crank arm 129 piston 131 trigger 131a notch 133 power switch 137 tool holder 141 cylinder 141a air chamber 143 striker 145 impact bolt 151 lock-on mechanism (trigger lock switch)
153 Switch holder 153a Guide groove 155 Lock-on button (switching operation member)
155a Plane portion 155b Knob portion 155c Shaft portion 157 Lock-on lever (locking member)
157a Shaft 157b Locking claw 157c Upper surface 161 Position holding mechanism 163 Steel ball 165a Groove 165b for lock-on position Groove 167 for lock-on release position Coil spring 171 Lock-on mechanism (trigger lock switch)
173 Switch holder 173a Guide groove 173b Projection piece 175 Lock-on button (switching operation member)
175a Plane portion 175b Knob portion 175c Shaft portion 177 Lock-on lever (locking member)
177a Shaft 177b Locking claw 177c Upper surface 181 Position holding mechanism 183 Projection 185a Groove 185b for lock-on position Groove 187 for lock-on release position Leaf spring

Claims (3)

A motor,
A work tool body for housing the motor;
A tool bit attached to the tip region of the work tool body and driven by the motor to perform a striking motion in the long axis direction;
A grip disposed on the rear side of the work tool main body opposite to the tool bit and extending in a direction intersecting with the long axis direction of the tool bit;
A connecting region extending in the longitudinal direction of the tool bit and connecting the rear portion of the work tool body and the upper portion of the grip;
A trigger disposed on the grip, moved to a motor driving position for energizing and driving the motor by a pulling operation by an operator, and returned to a motor stop position for stopping the energizing driving of the motor as the pulling operation is released A striking tool having
The trigger lock switch is disposed on the upper surface of the connection region or both the left and right side surfaces, and the trigger lock switch is operated in a direction along the outer surface of the connection region to lock the trigger at the motor drive position. A striking tool characterized in that it can be switched between a trigger lock position to be triggered and a trigger lock release position to unlock the trigger. The impact tool according to claim 1,
The strike tool according to claim 1, wherein an operation direction of the trigger lock switch is set in the same direction as a pull operation direction of the trigger. The impact tool according to claim 2,
The trigger lock switch includes a switching operation member that is switched between the trigger lock position and the trigger lock release position, and the trigger that is operated when the trigger is pulled to the motor drive position. A locking member that pivots toward the front portion in the return direction and locks to the front portion,
When the switching operation member is switched to the trigger lock position in a state where the trigger is pulled to the motor drive position, the switching operation member is from a direction intersecting the operation direction of the switching operation member with respect to the locking member. A striking tool that is configured to maintain the locked state of the locking member with respect to the front surface portion even when the operator releases the trigger pulling operation.

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