JP7118706B2 - hand tool - Google Patents

Description

The present invention relates to a hand-held tool, such as a disk grinder, which is used by an operator.

For example, hand-held tools such as disc grinders used for grinding work should be hung with tether straps or other hanging tools to prevent them from being accidentally dropped, especially when working at heights. Provisions are made to tie it to scaffolding or handrails. The following patent documents disclose techniques related to hooks for connecting this type of hanging tool and for hanging the hand-held tool from a work belt, scaffolding, or the like when work is interrupted.

JP 2006-326753 A JP 2015-178154 A

For this type of hand-held tool, the connecting part that connects a hanging tool such as a tether strap for fall prevention may be damaged due to a large impact applied via the hanging tool, and as a result, the hanging function will be damaged. In the past, sufficient measures were not taken to prevent workers from continuing to use the hanging tool without knowing this fact.

The present invention notifies a worker of the fact that a connecting part for connecting a hanging tool for fall prevention is damaged or the like so that the original hanging function of the hanging tool can be reliably performed. The purpose is to

The above problems are solved by the following inventions. A first invention is a hand-held tool that is held in a hand and used by an operator. A hand-held tool according to a first aspect of the present invention has a connecting portion for connecting a hanging tool. In the first invention, the connecting portion includes a connecting member supported so as to be displaceable between a first position and a second position with respect to the housing; A first position holding member is provided. The coupling member is configured to be displaced to the second position by deformation of the first position holding member.

According to the first invention, a suspension tool such as a tether strap is coupled to the coupling member held at the first position by the first position holding member. When an impact is applied to the coupling member via the suspension, the first position holding member is deformed by the impact, displacing the coupling member from the first position to the second position. Displacement of the coupling member to the second position provides visual notification to the surroundings that the coupling has been damaged. By visually notifying that the connecting portion has been damaged, the operator can recognize that maintenance such as replacement of the first position holding member and the connecting member is necessary, and thus the suspension can be resumed. It is possible to ensure that the hanging function of the hanging tool (the function of the connecting portion) is exhibited.

A second invention is the hand-held tool according to the first invention, further comprising a second position holding member for holding the coupling member at the second position.

According to the second aspect of the invention, once the connecting member is displaced to the second position due to damage to the connecting portion, the connecting member is held at the second position by the second position holding member. Therefore, it is reliably reported that the joint has been damaged.

In a third aspect based on the first aspect, after the coupling member is displaced to the second position, the position holding function of the first position holding member is lost, and the coupling member moves between the first position and the second position. It is a hand-held tool configured to be freely movable between positions.

According to the third aspect of the invention, when the connecting portion is damaged, the connecting member becomes freely movable between the first position and the second position (rattling vibration state), and the connecting portion is damaged. You will be notified that it has been received.

A fourth invention is the hand-held tool according to the first or second invention, wherein a spring is used as the first position holding member.

According to the fourth invention, the coupling member is held at the first position by the spring. When an impact is applied to the coupling member through the suspension, the coupling member is displaced to the second position by stretching the first position holding member, such as a tension spring, beyond the elastic region and plastically deforming. By plastically deforming the spring as the first position holding member, the coupling member is held in the second position and the damage to the coupling portion is notified.

A fifth invention is a hand-held tool according to the first or second invention, wherein a shaft member is used as the first position holding member.

According to the fifth invention, the coupling member is held at the first position by the shaft member. When an impact is applied to the coupling member via the suspension, the coupling member is displaced to the second position by breaking the shaft member as the first position holding member and disengaging the coupling member. When the shaft member as the first position holding member is disengaged and not returned to the original position, the connecting member is held at the second position and the damage to the connecting portion is notified.

In a sixth aspect, in any one of the first to fifth aspects, the first position holding member has a function of restricting the displacement of the coupling member displaced to the second position to the first position. It is a handheld tool.

According to the sixth invention, when the coupling member is displaced to the second position due to the impact applied through the suspension member, the plastically deformed first position holding member restricts the coupling member from returning to the first position. to notify that the joint has been damaged. The first position holding member has both the function of restricting the displacement of the coupling member from the first position to the second position and the function of restricting the return from the second position to the first position. It is possible to reduce the size of the connecting portion and simplify the configuration.

A seventh invention is the hand-held tool according to any one of the first to sixth inventions, wherein when the connecting member is displaced to the second position, activation of the main body is restricted.

According to the seventh invention, when the connecting part is damaged by the impact applied through the suspension tool, and if the connecting part is used as it is, the suspension function may not be sufficiently exhibited. , the coupling member is displaced to the second position, indicating that the coupling has been damaged. In addition, since the main body portion cannot be activated, it is possible to more reliably notify that the connecting portion has been damaged, and use of the hand-held tool in a state in which the connecting portion has been damaged is prevented.

1 is an overall side view of a hand-held tool having a coupling portion according to a first embodiment; FIG. This figure shows a state in which the coupling member is positioned at the first position. FIG. 4 is a longitudinal sectional view of a coupling portion according to the first embodiment; This figure shows a state in which the coupling member is positioned at the first position. FIG. 4 is an exploded perspective view of a coupling portion according to the first embodiment; 1 is an overall side view of a hand-held tool having a coupling portion according to a first embodiment; FIG. This figure shows a state in which the connecting member is positioned at the second position. FIG. 4 is a longitudinal sectional view of a coupling portion according to the first embodiment; This figure shows a state in which the connecting member is positioned at the second position. FIG. 8 is a vertical cross-sectional view of a coupling portion according to a second embodiment; This figure shows a state in which the coupling member is positioned at the first position. FIG. 8 is a vertical cross-sectional view of a coupling portion according to a second embodiment; This figure shows a state in which the connecting member is positioned at the first position and the switch is turned on. FIG. 8 is an exploded perspective view of a coupling portion according to the second embodiment; FIG. 8 is a vertical cross-sectional view of a coupling portion according to a second embodiment; This figure shows a state in which the connecting member is positioned at the second position. FIG. 11 is a vertical cross-sectional view of a coupling portion according to a third embodiment; This figure shows a state in which the coupling member is positioned at the first position. FIG. 11 is a vertical cross-sectional view of a coupling portion according to a third embodiment; This figure shows a state in which the connecting member is positioned at the second position. FIG. 11 is an exploded perspective view of a coupling portion according to a third embodiment; FIG. 11 is a perspective view of a hand-held tool with a coupling portion according to a fourth embodiment; This figure shows a state in which the left side of the rear case is removed to expose the coupling portion. This figure shows a state in which the coupling member is in the first position. FIG. 11 is a perspective view of a coupling portion according to a fourth embodiment; This figure shows a state in which the coupling member is positioned at the first position. FIG. 11 is a perspective view of a coupling portion according to a fourth embodiment; This figure shows a state in which the connecting member is positioned at the second position. It is a side view of the coupling|bond part which concerns on 4th Embodiment. This figure shows a state in which the coupling member is positioned at the first position. It is a side view of the coupling|bond part which concerns on 4th Embodiment. This figure shows a state in which the connecting member is positioned at the second position. FIG. 11 is a plan view of a coupling portion according to a fourth embodiment; This figure shows a state in which the coupling member is positioned at the first position. In this figure, the engagement arm in the open state is indicated by a two-dot chain line. FIG. 11 is a plan view of a coupling portion according to a fourth embodiment; This figure shows a state in which the connecting member is positioned at the second position. FIG. 11 is a perspective view of a hand-held tool with a coupling portion according to a fourth embodiment; This figure shows a state in which the left side of the rear case is removed to expose the coupling portion. This figure shows a state in which the coupling member is positioned at the second position. FIG. 11 is a side view of a handheld tool with a coupling according to a fourth embodiment; This figure shows a state in which the left side of the rear case is removed to expose the coupling portion. This figure shows a state in which the coupling member is positioned at the second position.

Next, embodiments of the present invention will be described with reference to FIGS. 1 to 21. FIG. 1 to 5 show a handheld tool 1 according to a first embodiment of the invention. In the first embodiment, a disc grinder is exemplified as the hand-held tool 1 . This hand-held tool 1 has a main body 3 in which an electric motor 2 as a drive source is housed in a cylindrical main body housing 3a. The main body housing 3a functions as a grip section by setting a thickness that allows the user to easily hold it with one hand.

A large switch lever 8 is provided on the lower surface of the main body 3 so as to be vertically tiltable. The electric motor 2 is activated when the switch lever 8 is pulled upward with the fingertip of the hand holding the main body 3 . The switch lever 8 is provided with a small lock-off lever 8a. As shown in the figure, when the lock-off lever 8a is raised, the switch lever 8 cannot be pulled upward, so the electric motor 2 is maintained in a stopped state (lock-off state). By tilting the lock-off lever 8a rearward to release the lock-off state, the switch lever 8 can be pulled upward.

A gear head portion 4 is coupled to the front side of the body portion 3 . The gear head portion 4 incorporates a gear train (not shown in the figure) that reduces the speed of the output of the electric motor 2 and outputs it to the spindle 4a. The spindle 4 a is perpendicular to the motor axis of the electric motor 2 . The spindle 4 a protrudes downward from the lower surface of the gear head portion 4 . A circular grindstone 5 is attached to the lower portion of the spindle 4a. The rear side of the grindstone 5 is covered with a cover 6. - 特許庁

The rear portion of the body portion 3 is covered with a rear case 7 having a left and right split structure. FIG. 3 shows a state in which the left half case 7a is removed. The left and right half cases 7a and 7b are coupled together by being screwed together at a total of four screwing portions 7d. As shown in FIGS. 2 and 3, a main switch 9 is housed inside a rear case 7 formed by butting left and right half cases 7a and 7b. A switch arm 10 is provided in the lower part of the rear case 7 so as to be vertically tiltable via a support shaft 10a. A front end of the switch arm 10 is engaged with a rear portion of the switch lever 8 . Therefore, the switch arm 10 tilts up and down in association with the vertical movement of the switch lever 8 . When the switch lever 8 is pulled upward, its rear portion is displaced upward and the switch arm 10 tilts upward (clockwise in FIG. 2). An upper surface of the switch arm 10 is provided with an operating projection 10b. The actuating projection 10b is arranged to face the actuating button 9a of the main switch 9. As shown in FIG. Therefore, when the switch arm 10 is tilted upward, the operating button 9a is pushed upward by the operating protrusion 10b, and the main switch 9 is turned on.

The rear surface and left and right side portions of the rear case 7 are provided with a large number of intake ports 7c for introducing outside air. Although not visible in the drawing, a cooling fan is attached to the output shaft of the electric motor 2 . When the electric motor 2 is activated, the cooling fan rotates, and outside air is introduced into the rear case 7 and the main body housing 3a through the intake port 7c. The electric motor 2 is mainly cooled by the introduced outside air (motor cooling air). Motor cooling air is exhausted to the outside from the vicinity of the joint between the main body portion 3 and the gear head portion 4 .

In this embodiment, an AC power type hand-held tool 1 is exemplified. A single power cord 11 is pulled out from the rear surface of the rear case 7 . AC power is supplied through the power cord 11 .

The hand-held tool 1 of the first embodiment is provided with a connecting portion 15 for connecting a hanging tool S such as a tether strap for preventing dropping during work. The coupling portion 15 according to the first embodiment includes a coupling member 16 provided on the rear case 7 so as to be displaceable between a first position and a second position, and holds the coupling member 16 at the first position. A tension spring 17 is provided as a first position holding member for.

As shown in FIGS. 2 and 3, an inverted U-shaped frame 18 is attached to the lower rear surface of the rear case 7 and above the switch arm 10 . The frame 18 is sandwiched between the left and right half cases 7a and 7b and assembled so as not to be displaceable. In addition, as shown in the figure, the frame 18 also has a left-right half split structure. A coupling member 16 is supported by the frame 18 so as to be slidable forward and backward.

The coupling member 16 has an annular hook portion 16a at its rear portion. The hook portion 16 a protrudes rearward from the frame 18 , and thus protrudes further rearward than the rear surface of the rear case 7 . A hanging tool S such as a tether strap can be connected to the hook portion 16a.

A tension spring 17 is interposed between the frame 18 and the connecting member 16 . A front side spring pin 18a is provided on the front portion of the frame 18 . The coupling member 16 is provided with a rear spring pin 16b. The front side of the tension spring 17 is hooked on the front spring pin 18a, and the rear side thereof is hooked on the rear spring pin 16b. The tension spring 17 holds the coupling member 16 in the first position shown in FIG. As shown in FIG. 2, the first position is the displaceable front end position of the coupling member 16. For example, the hook portion 16a contacts the rear portion of the frame 18 and cannot be displaced forward any further. be able to. The rear portion of the frame 18 is provided with a semicircular recess 18b for releasing the screwing portion 7d. The hooking portion 16a abuts against the concave portion 18b to restrict the position of the front end of the coupling member 16. As shown in FIG.

The upper portion of the coupling member 16 is provided with a relief recess 16 c for releasing the recess 18 b of the frame 18 . The escape recess 16c is formed long in the front-rear direction with a width that allows the recess 18b of the frame 18 to be inserted. The coupling member 16 can be displaced back and forth with respect to the rear case 7 within the range in which the recess 18b can be relatively displaced within the escape recess 16c. The front end position of the range in which the coupling member 16 can be displaced in the front-rear direction is set at the first position, and the rear end position is set at the second position.

When the coupling member 16 is subjected to an impact, such as when it is dropped, through the suspension member S, the coupling member 16 is displaced rearward against the biasing force of the tension spring 17 . However, when the impact is weak, the coupling member 16 is displaced within the elastic region of the tension spring 17, so that when the impact is removed, the coupling member 16 is returned to the first position by the biasing force of the tension spring 17. . In the first embodiment, this tension spring 17 corresponds to the first position holding member.

When the impact applied to the coupling member 16 through the suspension device S is large, the tension spring 17 is plastically deformed beyond the elastic region, and as a result the coupling member 16 is displaced to the second position. 4 and 5 show a state in which the coupling member 16 has been displaced to the second position. The second position corresponds to a retracted end position where the recessed portion 18b of the frame 18 abuts the relief recessed portion 16c at the front end and further retraction is impossible. When the coupling member 16 is displaced to the second position as shown in FIG. 4, the notification indicator 16d provided on the side surface can be visually confirmed. By visually confirming this indicator 16d, the user can recognize that the coupling member 16 has been displaced to the second position.

When the coupling member 16 is displaced to the second position, the tension spring 17 is plastically deformed beyond its elastic region, so that the coupling member 16 is held in the second position even after the impact is removed. As a result, it is reliably reported that the connecting portion 15 has been damaged.

When the coupling member 16 is displaced to the second position, the switch lever 8 cannot be pulled. A restriction projection 16 e is provided on the lower surface of the coupling member 16 . On the other hand, the upper surface of the switch arm 10 is provided with an abutment base portion 10c which is one step higher. When the coupling member 16 is displaced to the second position, the restriction convex portion 16e rides on the contact base portion 10c. In this state, the switch arm 10 is restricted from being displaced toward the ON position, so that the switch lever 8 cannot be pulled upward. Therefore, when the coupling portion 15 is damaged and the coupling member 16 is displaced to the second position, the electric motor 2 cannot be started, and the hand-held tool 1 becomes unusable.

According to the coupling portion 15 of the first embodiment described above, the suspension tool S such as a tether strap is coupled to the coupling member 16 held at the first position by the tension spring 17 as the first position holding member. be. A state in which the coupling member 16 is positioned at the first position is a normal state of the coupling portion 15, and the suspension tool S exhibits a sufficient suspension function in this normal state.

When an impact is applied to the coupling member 16 through the suspension device S, the tension spring 17 is plastically deformed by the impact and the coupling member 16 is displaced from the first position to the second position. By displacing the connecting member 16 to the second position, it is visually notified to the surroundings that the connecting portion 15 has been damaged. When the coupling member 16 is displaced to the second position, the indicator 16d is exposed and the position of the coupling member 16 is reliably notified.

By visually notifying that the connecting portion 15 has been damaged, the operator recognizes that it is necessary to perform maintenance such as replacement of the tension spring 17 as the first position holding member and the connecting member 16. As a result, the hanging function of the hanging tool S (the function of the connecting portion 15) can be reliably exhibited.

Further, the connecting member 16 is displaced to the second position by plastically deforming the tension spring 17 as the first position holding member. Since the tension spring 17 is plastically deformed beyond the elastic region, once displaced to the second position, the coupling member 16 is held at the second position without being returned to the first position. Therefore, in the coupling portion 15 according to the first embodiment, the tension spring 17 as the first position holding member also functions as the second position holding member for holding the coupling member 16 at the second position. The connecting member 16 is held at the second position while being restrained from being displaced to the first position by the tension spring 17, which also functions as a second position holding member, so that the connecting portion 15 is damaged. is reported more reliably.

By performing maintenance such as replacing the plastically deformed tension spring 17, the coupling member 16 can be restored to the normal state in which it is held at the first position, thereby restoring the coupling portion 15 to its normal state. state can be used.

Furthermore, according to the coupling portion 15 of the first embodiment, when the coupling member 16 is displaced to the second position due to the impact received through the suspension member S, the switch arm 10 is restricted from being displaced to the ON side. , the switch lever 8 cannot be pulled, and the start of the electric motor 2 is restricted. Since the main body portion 3 cannot be started in this manner, it is possible to more reliably notify that the coupling portion 15 has been damaged, and to prevent the hand-held tool 1 from being used while the coupling portion 15 is damaged. Avoided.

From FIG. 6 onwards, the connecting part 20 according to the second embodiment is shown. As shown in FIG. 8, the coupling portion 20 of the second embodiment includes a shaft member 22 instead of the tension spring 17 as a first position holding member for holding the coupling member 21 at the first position. The second embodiment is different from the first embodiment in that an engagement shaft 23 is provided as a second position holding member that holds the at the second position. For members and configurations that do not require change, the same reference numerals are used and the description thereof is omitted.

A coupling member 21 according to the second embodiment is supported by an inverted U-shaped frame 18 attached to the lower surface of the rear case 7 so as to be slidable forward and backward. A ring-shaped hook portion 21 a is provided at the rear portion of the coupling member 21 . The hook portion 21a protrudes rearward from the rear surface of the rear case 7 . A hanging tool S such as a tether strap is connected to the hook portion 21a.

The connecting member 21 is connected to the frame 18 by the shaft member 22 . As shown in FIGS. 6 and 7 , the coupling member 21 is held at the first position with respect to the frame 18 by the shaft member 22 . As shown in FIG. 9, when the shaft member 22 is detached from either the coupling member 21 or the frame 18, the coupling member 21 is displaced to the second rearward position with respect to the frame 18. As shown in FIG.

An engaging shaft 23 is supported on the upper surface of the coupling member 21 so as to be vertically displaceable. The engaging shaft 23 is urged by a compression spring 24 in a direction of protruding upward. As shown in FIGS. 6 and 7, when the coupling member 21 is located at the first position, the engaging shaft 23 abuts against the upper portion of the frame 18 and is in the retracted position where it does not protrude from the upper surface of the coupling member 21. held. An engagement hole 18 c is provided in the upper portion of the frame 18 . As shown in FIG. 9, when the coupling member 21 is displaced to the second position, the engagement shaft 23 is displaced below the engagement hole 18c, and as a result, the engagement shaft 23 is pushed into the engagement hole 18c by the compression spring 24. It will stick out. When the engaging shaft 23 protrudes into the engaging hole 18c, the engaging member 21 is held at the second position and is restricted from returning to the first position.

As in the first embodiment, the connecting member 21 is provided with a restricting protrusion 21b, an escape recess 21c, and an indicator 21d. As shown in FIG. 9, when the engaging member 21 is displaced to the second position, the regulating projection 21b rides on the abutment base 10c of the switch arm 10, so that the switch lever 8 cannot be pulled. , so that the electric motor 2 cannot be started. The screwed portion 7d and the recessed portion 18b of the frame 18 for releasing the screwed portion 7d are inserted into the relief recessed portion 21c. The coupling member 21 can be displaced in the front-rear direction within a range in which the screwing portion 7d and the recessed portion 18b can be relatively displaced within the relief recessed portion 21c. As shown in FIGS. 6 and 7, when the coupling member 21 is positioned at the first position, the hooking portion 21a is in contact with the concave portion 18b.

A shaft member 22 is attached to the front portion of the coupling member 21 . The shaft member 22 protrudes laterally from the left and right side portions of the coupling member 21 . Both ends of the shaft member 22 are inserted into engagement holes 18d provided on the left and right sides of the front portion of the frame 18, respectively, so that the coupling member 21 is held at the first position. In a normal state in which the coupling member 21 is held at the first position and the hanging function of the hanging member S can be fully exhibited, the switch lever 8 is pulled as shown in FIG. The switch 9 can be turned on and thus the hand-held tool 1 can be used.

As shown in FIG. 9, when a large impact is applied to the coupling member 21 through the suspension member S, and as a result the shaft member 22 is disengaged from the engaging hole 18d and the coupling member 21 is displaced to the second position, the indicator 21d is activated. The fact that the connecting member 21 has been exposed and displaced to the second position is reliably reported to the surroundings.

According to the coupling portion 20 of the second embodiment described above, the suspension tool S such as a tether strap is coupled to the coupling member 21 held at the first position by the shaft member 22 as the first position holding member. be. A state in which the connecting member 21 is positioned at the first position is a normal state of the connecting portion 20, and the hanging tool S can perform a sufficient hanging function in this normal state.

When an impact is applied to the coupling member 21 via the suspension tool S, the shaft member 22 is disengaged from the engagement hole 18d by the impact, and the coupling member 21 is displaced from the first position to the second position. By displacing the connecting member 21 to the second position, it is notified to the surroundings that the connecting portion 20 has been damaged. By notifying that the connecting portion 20 has been damaged in this manner, the need for maintenance of the connecting portion 20 is notified, and as a result, the hanging function of the connecting portion 20 can be fully exhibited.

In addition, in the second embodiment, once the connecting member 21 is displaced to the second position, the engaging shaft 23 enters the engaging hole 18c so that the connecting member 21 is held at the second position and moved to the first position. The return to the position of 1 is restricted, so that the fact that the connecting portion 20 has been damaged can be reported more reliably.

Furthermore, in the second embodiment as well, if the coupling portion 20 is damaged and the coupling member 21 is displaced to the second position, the switch lever 8 cannot be turned on, and the hand-held tool 1 cannot be used. . As a result, it is reliably reported that the connecting portion 20 has been damaged, and the necessity of maintenance is reported.

In the coupling portion 20 of the second embodiment, by performing maintenance such as replacing the shaft member 22, the frame 18, etc., the coupling member 21 can be restored to the normal state in which it is held at the first position. By performing necessary maintenance, the connecting portion 20 can be used again in a normal state.

FIGS. 10 to 12 show the connecting portion 30 according to the third embodiment. The connecting portion 30 of the third embodiment has a configuration in which a power supply circuit cutoff function is added to the connecting portion 20 of the second embodiment. For members and configurations that do not require change, the same symbols are used, and descriptions thereof are omitted.

In the third embodiment, a circuit conducting portion 31 is interposed between the frame 18 and the coupling member 21. As shown in FIG. The circuit conducting portion 31 includes contact portions 31a and 31b attached to the frame 18 side and a conducting portion 31c attached to the coupling member 21 side. A conductive plate formed by bending a conductive band steel plate into a U-shape is used for the conductive portion 31c. The contact portions 31a and 31b are electrically incorporated in the power supply circuit. Each of the contact portions 31a and 31b has a bifurcated structure having elasticity on the closing side. The ends of the conducting portion 31c are elastically sandwiched between the contact portions 31a and 31b to maintain the connected state. As shown in FIG. 10, in a normal state (a state in which a sufficient hanging function is exhibited) in which the coupling member 21 is positioned at the first position, both ends of the conductive portion 31c are inserted into the contact portions 31a and 31b. , the two contact portions 31a and 31b are electrically connected through one conducting portion 31c. Electrical conduction between the two contact portions 31a and 31b causes the power supply circuit to be in a conduction state, and the electric motor 2 is started by turning on the switch lever 8 in this conduction state.

As shown in FIG. 11, when an impact is applied to the coupling member 21 via the hanging member S, the shaft portion 22 is disengaged from the frame 18 or the coupling member 21, and as a result, the coupling member 21 is displaced toward the second position. The conductive portion 31c is separated from the contact portions 31a and 31b. Both ends of the conductive portion 31c are displaced rearward against the elastic sandwiching force of the contact portions 31a and 31b (while displacing the contact portions 31a and 31b in the opening direction) to separate from the contact portions 31a and 31b. . When the conductive portion 31c is separated from the contact portions 31a and 31b, the electrical connection between the contact portions 31a and 31b is lost and the power supply circuit is cut off.

When the coupling member 21 is displaced to the second position and the power supply circuit is cut off, the electric motor 2 does not start even if the switch lever 8 is pulled to turn on the main switch 9 . As described above, in the third embodiment, when the coupling member 21 is displaced to the second position, the electric motor 2 cannot be started because the power supply circuit is interrupted. The restriction protrusions 16e and 21b that restrict the displacement of the switch arm 10 toward the ON position are omitted. In the first and second embodiments, the restricting projections 16e and 21b abut against the abutment base portion 10c, thereby inhibiting the tilting operation of the switch arm 10 to the ON side and thus the ON operation of the switch lever 8. , the start-up of the electric motor 2 is avoided. On the other hand, in the third embodiment, although the switch lever 8 can be tilted, the electric motor 2 is prevented from starting by shutting off the power supply circuit. This differs from the first and second embodiments in that the ON operation of 8 is invalidated.

Even with the connecting portion 30 of the third embodiment described above, when a large impact is applied to the connecting member 21 via the suspension S and the connecting member 21 is displaced to the second position, the connecting portion 30 is The surroundings are notified of the damage or the like. In addition, the indicator 21d exposed by displacing the connecting member 21 to the second position allows for reliable visual confirmation. Further, once the coupling member 21 is displaced to the second position, the engagement shaft 23 enters the engagement hole 18c, and the return of the coupling member 21 to the first position is restricted. Also, it is reliably notified that the connecting portion 30 has been damaged or the like.

In the third embodiment as well, the displacement of the connecting member 21 informs the user that the joint 30 has been damaged. Therefore, the reliable hanging function of the connecting portion 30 can be exhibited.

Furthermore, according to the third embodiment as well, when the coupling portion 30 is damaged and the coupling member 21 is displaced to the second position, the power supply circuit is interrupted and the electric motor 2 cannot be started. Reliable notification is made.

13 to 21 show a hand-held tool 1 of a fourth embodiment. Since the basic configuration of the hand-held tool 1 does not need to be changed, the same symbols are used and the description thereof is omitted. In the fourth embodiment, a connecting portion 40 for connecting a suspension member S such as a tether strap has a configuration different from that of the first to third embodiments. The basic configuration of the hand-held tool 1 does not require any change. For members and configurations that do not require change, the same reference numerals are used and the description thereof is omitted.

The connecting portion 40 of the fourth embodiment is arranged on the upper rear surface of the rear case 7 and above the power cord 11 . Details of the coupling portion 40 of the fourth embodiment are shown in FIGS. 14-19. The connecting portion 40 of the fourth embodiment includes a connecting member 41 for connecting a suspension tool S such as a tether strap, a first position holding member 42 for holding the connecting member 41 at a first position, and a connecting A second position holding member for holding the member 41 at the second position and an engaging shaft 44 for regulating the retreating end of the coupling member 41 are provided.

The coupling member 41 has an oval annular shape that is long in the front-rear direction. A hanging tool S is coupled to the rear portion of the coupling member 41 . A first position holding member 42 is engaged with the front portion of the coupling member 41 . The first position holding member 42 has a pair of left and right engaging arms 42a. The rear portions of the pair of left and right engaging arms 42a are bent in an L-shape toward the side approaching each other to form bent portions 42b. Both engaging arms 42a have an elastic force in a direction to bring the bent portions 42b on the rear side closer to each other. Both engaging arms 42a are attached to the left and right side surfaces of the base portion 43 in parallel to each other. The pedestal portion 43 is fixed to the rear case 7 side and further to the main body portion 3 side.

The pair of left and right engaging arms 42a are brought into a closed state in which the bent portions 42b at the rear portions are overlapped with each other by elastic force, so that the connecting member 41 is moved to the first position (a state in which the bent portions 42b are positioned on the inner peripheral side). ). 13, 14, 16, and 18 each show a normal state in which the coupling member 41 is held at the first position. When a large impact is applied to the coupling member 41 via the hanging tool S, the front portion of the coupling member 41 is pressed against the bent portions 42b of the pair of left and right engaging arms 42a. By applying an external force in the push-open direction (rearward direction) to both bent portions 42b via the coupling member 41, both engaging arms 42a are displaced in directions away from each other against the elastic force, and both bent portions The superposition state of 42b is opened. By pushing the engagement arm 42a open, the coupling member 41 is displaced from the first position to the second position.

As shown in FIG. 13, an engagement shaft 44 as a second position holding member is positioned on the inner peripheral side of the coupling member 41 . The engaging shaft 44 is fixed to the rear case 7 side. Therefore, when the coupling member 41 displaces the pair of left and right engaging arms 42a in the opening direction against the elastic force and is displaced rearward, the engaging shaft 44 restricts further backward movement. becomes. A retracted end position regulated by the engaging shaft 44 corresponds to the second position. A state in which the coupling member 41 is displaced to the second position is shown in FIGS. 15, 17, 19, 20 and 21. FIG.

When the coupling member 41 is displaced from the first position to the second position, the left and right engaging arms 42a are returned toward each other by their own elastic force. When the pair of left and right engaging arms 42a is returned, the respective bent portions 42b are overlapped again to return to the closed state. By closing the pair of left and right engaging arms 42a in this manner, the coupling member 41 once displaced to the second position is prevented from being returned to the first position and is held at the second position. Therefore, the bent portion 42b of the pair of left and right engaging arms 42a functions as a first position holding member that holds the coupling member 41 at the first position and holds the coupling member 41 at the second position. It also has a function as a second position holding member to prevent it from returning to the first position.

A pair of left and right engaging arms 42a serving as second position holding members hold the connecting member 41 in a displaced state at the second position, thereby informing the surroundings that the connecting portion 40 has been damaged or the like. Therefore, the need for maintenance of the joint 40 is notified. As described above, the coupling member 41 held at the second position with the pair of right and left engaging arms 42a closed makes rattling noises in the range where it is not returned to the first position and where it is not engaged with the engaging shaft 44. It will be in a state of being able to move back and forth while emitting a .

In the case of the fourth embodiment, the connecting member 41 can be returned to the first position by removing the rear case 7 and opening the left and right engaging arms 42a. Therefore, in the fourth embodiment, the connecting portion 40 can be restored to its normal state without replacing parts such as the engaging arm 42a, which is different from the first to third embodiments. there is

According to the connecting portion 40 of the fourth embodiment described above, in a normal state in which the connecting member 41 to which the hanging tool S is connected is held at the first position, the hanging tool S prevents the hand-held tool 1 from being damaged. Prevents accidental falls. When a large impact is applied to the coupling portion 40 through the suspension member S when the fall is prevented, the coupling portion 40 is damaged by displacing the coupling member 41 to the second position. visually notified. By confirming that the connecting member 41 has been displaced to the second position, the user can recognize the need for maintenance of the connecting portion 40, and can decide to stop using it after that. can be done.

For maintenance of the connecting portion 40, it is sufficient to open the left and right engaging arms 42a and return the connecting member 41 to the first position. In the fourth embodiment, the pair of left and right engaging arms 42a is illustrated, but the coupling member 41 can be held at the first position by only one engaging arm.

Further modifications can be added to each of the embodiments described above. Although the connection parts 15, 20, 30, and 40 for connecting the suspension tool S such as a tether strap are provided at the rear part of the hand-held tool 1, they may be provided at the side part or the front part.

Although a disc grinder is exemplified as the hand-held tool 1, the exemplified coupling portion can be applied to drilling tools such as hammer drills and other electric tools or power tools such as cutting machines. Moreover, although the hand-held tool 1 of the AC power supply type is illustrated, the connecting portion illustrated as an example can be applied to a rechargeable hand-held tool powered by a battery pack that can be used repeatedly by charging.

S: Hanging tool 1: Hand-held tool (disk grinder)
DESCRIPTION OF SYMBOLS 2... Electric motor 3... Main body part 3a... Main body housing 4... Gear head part 4a... Spindle 5... Grindstone 6... Cover 7... Rear case 7a... Left half case 7b... Right half case 7c... Inlet, 7d Screwing portion 8 Switch lever 9 Main switch 9a Operation button 10 Switch arm 10a Support shaft 10b Operation convex portion 10c Abutment base 11 Power supply cord 15 Coupling (first embodiment)
Reference numeral 16: Coupling member 16a: Hook portion 16b: Rear spring pin 16c: Relief recess 16d: Indicator 16e: Regulating projection 17: Tension spring (first position holding member/second position holding member)
Reference Signs List 18 Frame 18a Front spring pin 18b Recessed portion 18c Engagement hole 18d Engagement hole 20 Coupling portion (second embodiment)
Reference numeral 21: Coupling member 21a: Hook portion 21b: Regulating convex portion 21c: Escape recessed portion 21d: Indicator 22: Shaft member (first position holding member)
23... Engagement shaft (second position holding member)
24... Compression spring 30... Coupling portion (third embodiment)
31...Circuit conduction part 31a, 31b...Contact part 31c...Conduction part 40...Coupling part (fourth embodiment)
41... Coupling member 42... First position holding member 42a... Engagement arm 42b... Bent part 43... Base part 44... Engagement shaft

Claims (8)

A hand-held tool held by a worker for use,
a coupling portion for coupling the suspension, the coupling portion comprising a coupling member supported so as to be displaceable between a first position and a second position with respect to the housing; A first position holding member for holding the at the first position,
The first position holding member is deformed by an external force in the anti-suspension direction applied to the coupling member through the suspension tool, and the coupling member is displaced to the second position, thereby causing damage to the coupling portion. A handheld tool configured to be notified. A handheld tool according to claim 1, comprising:
A hand tool comprising a second position retaining member for retaining said coupling member in said second position. A handheld tool according to claim 1 or 2,
A hand-held tool, wherein a spring is interposed as the first position holding member between the housing and the coupling member, and the coupling member is held at the first position by the urging force of the spring . A handheld tool according to claim 1 or 2,
One of the housing and the coupling member has a shaft member as the first position holding member, and the other has an engagement hole into which the shaft member is detachably inserted, and the shaft member is the engagement hole. a hand-held tool configured to be inserted into and hold said coupling member in said first position . A hand-held tool according to any one of claims 1 to 4 ,
The hand-held tool, wherein the first position holding member also has a function of restricting the displacement of the coupling member displaced to the second position to the first position. A handheld tool according to claim 1, comprising:
After the coupling member is displaced to the second position, the position holding function of the first position holding member is lost so that the coupling member can move freely between the first position and the second position. A handheld tool configured to be movable. A hand-held tool held by a worker for use,
a coupling portion for coupling the suspension, the coupling portion comprising a coupling member supported so as to be displaceable between a first position and a second position with respect to the housing; at the first position, wherein deformation of the first position holding member displaces the coupling member to the second position ;
After the coupling member is displaced to the second position, the position holding function of the first position holding member is lost so that the coupling member can move freely between the first position and the second position. A handheld tool configured to be movable . A handheld tool according to any one of claims 1 to 7 ,
A hand-held tool configured such that when the coupling member is displaced to the second position, activation of the main body is restricted.

Images