JP2019181597A - Hand-held tool - Google Patents

Abstract

To take a measure to prevent a hand-held tool such as a disc grinder from falling by using a suspension instrument such as a tether strap when performing operation with the tool at an elevated place; and to report to an operator such an incident as when a connection part, to which the suspension instrument for fall prevention is connected, is damaged, so as to surely achieve the original suspension function of the suspension instrument.SOLUTION: When shock is added to a connection member 21 through a suspension instrument S, the connection member 21 is displaced to a second position by deformation of a first position holding member 22, and the activation of a body part 3 is regulated by allowing a conductive plate 31c to separate from contact parts 31a and 31b and a power supply circuit to be cut off.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a hand-held tool used by a worker, for example, a disc grinder.

  For example, for hand-held tools such as disc grinders used for grinding work, use hand-held tools such as tether straps to prevent accidental dropping, especially when working at high places. Measures are taken to connect to scaffolding and handrails. The following patent documents disclose a technique related to a hook for connecting this type of hanging tool or for hanging the hand-held tool on a work belt, a scaffold or the like when the work is interrupted.

JP 2006-326753 A JP2015-178154A

  For this type of hand-held tool, the coupling part that couples a hanging tool such as a tether strap for preventing fall is damaged by a large impact applied through the hanging tool, resulting in a hanging function. However, it has been assumed that no sufficient measures are taken to prevent the worker from continuing to use the hanging tool without knowing the fact.

  The present invention informs the operator of the fact when the connecting part for connecting the hanging tool for preventing the fall is damaged, so that the original hanging function of the hanging tool is surely performed. The purpose is to.

  The above problems are solved by the following inventions. The first invention is a hand-held tool used by an operator. The hand-held tool according to the first invention has a coupling portion for coupling the hanging tool. In the first invention, the coupling portion is configured to hold the coupling member in the first position, the coupling member supported to be displaceable between the first position and the second position with respect to the housing. A first position holding member is provided. In the first invention, the coupling member is displaced to the second position by the deformation of the first position holding member, and the activation of the main body is restricted.

  According to the first invention, the hanging 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 through the hanging tool, the first position holding member is deformed by the impact and the coupling member is displaced from the first position to the second position. When the coupling member is displaced to the second position, it is visually notified to the surroundings that the coupling portion has been damaged, and the main body portion cannot be activated. By visually informing that the coupling portion has been damaged due to the displacement of the coupling member and making the main body unable to start, the operator can perform maintenance such as replacement of the first position holding member and the coupling member. It is possible to recognize that it is necessary to do this, and thereby it is possible to ensure that the hanging function (function of the coupling portion) of the hanging tool is exhibited.

  A second invention is a hand-held tool according to the first invention, wherein the power supply circuit is shut off and activation of the main body is restricted.

  According to the second aspect of the invention, when the coupling member is displaced to the second position, the power supply circuit is shut off and the main body becomes unstartable.

  According to a third invention, in the second invention, a conductive plate is provided in the coupling member, a contact portion is provided in the frame body that supports the coupling member, and conduction is established by contact between the conductive plate and the contact portion in the power circuit. A circuit conduction portion is provided, and the conduction plate and the contact portion are brought into contact with each other at the first position, the circuit conduction portion is conducted to be in a power supply state, and the conduction plate is separated from the contact portion at the second position. Is a hand-held tool that is configured so that the power supply circuit is cut off by becoming non-conductive.

  According to the third invention, when the coupling member is displaced to the second position due to the impact applied through the hanging tool, the conductive plate is detached from the contact portion in the circuit conductive portion, and the power supply circuit is shut off. The fact that the connecting portion has been damaged is informed by the fact that the power supply circuit is shut off and the main body cannot be activated.

  A fourth invention is a handheld tool according to the third invention, wherein the conductive portion is held in contact by elastic pinching of the contact portion, and the conductive plate is separated by displacing the contact portion against elastic force. is there.

  According to the fourth invention, in the state where the coupling member is located at the first position, the conducting portion is held in contact by the elastic pinching force of the contact portion. When the coupling member is displaced to the second position, the contact portion is displaced in the opening direction against the elastic pinching force of the contact portion, and the conducting portion is separated, thereby shutting off the power supply circuit.

  According to a fifth invention, in any one of the first to fourth inventions, in a state where the coupling member is displaced to the second position, the on-operation of the switch lever is restricted and the activation of the main body is restricted. It is a hand-held tool.

  According to the fifth aspect of the present invention, when an impact is applied to the coupling member through the hanging tool, and the coupling member is displaced to the second position, the switch lever for activation cannot be operated, thereby the main body portion. The fact that the joint has been damaged is informed of the activation of the.

  A sixth invention is a hand-held tool according to any one of the first to fifth inventions, wherein the coupling member is configured to be restricted from being displaced to the first position after being displaced to the second position. .

  According to the sixth invention, since the state in which the coupling member is displaced to the second position can be more visually recognized, the fact that the coupling portion has been damaged is more reliably notified to the surroundings.

It is a whole side view of the hand-held tool provided with the coupling | bond part which concerns on 1st Embodiment. This figure has shown the state in which a coupling member is located in a 1st position. It is a longitudinal cross-sectional view of the coupling part according to the first embodiment. This figure has shown the state in which a coupling member is located in a 1st position. It is a disassembled perspective view of the coupling | bond part which concerns on 1st Embodiment. It is a whole side view of the hand-held tool provided with the coupling | bond part which concerns on 1st Embodiment. This figure has shown the state in which a coupling member is located in a 2nd position. It is a longitudinal cross-sectional view of the coupling part according to the first embodiment. This figure has shown the state in which a coupling member is located in a 2nd position. It is a longitudinal cross-sectional view of the coupling part according to the second embodiment. This figure has shown the state in which a coupling member is located in a 1st position. It is a longitudinal cross-sectional view of the coupling part according to the second embodiment. This figure shows a state where the coupling member is located at the first position and the switch is turned on. It is a disassembled perspective view of the coupling | bond part which concerns on 2nd Embodiment. It is a longitudinal cross-sectional view of the coupling part according to the second embodiment. This figure has shown the state in which a coupling member is located in a 2nd position. It is a longitudinal cross-sectional view of the coupling part according to the third embodiment. This figure has shown the state in which a coupling member is located in a 1st position. It is a longitudinal cross-sectional view of the coupling part according to the third embodiment. This figure has shown the state in which a coupling member is located in a 2nd position. It is a disassembled perspective view of the connection part which concerns on 3rd Embodiment. It is a perspective view of the hand-held tool provided with the connection part which concerns on 4th Embodiment. This figure shows a state where the left side of the rear case is removed and the coupling portion is exposed. This figure shows a state in which the coupling member is in the first position. It is a perspective view of the joint part concerning a 4th embodiment. This figure has shown the state in which a coupling member is located in a 1st position. It is a perspective view of the joint part concerning a 4th embodiment. This figure has shown the state in which a coupling member is located in a 2nd position. It is a side view of the joint part concerning a 4th embodiment. This figure has shown the state in which a coupling member is located in a 1st position. It is a side view of the joint part concerning a 4th embodiment. This figure has shown the state in which a coupling member is located in a 2nd position. It is a top view of the joint part concerning a 4th embodiment. This figure has shown the state in which a coupling member is located in a 1st position. In this figure, the engagement arm in the opened state is indicated by a two-dot chain line. It is a top view of the joint part concerning a 4th embodiment. This figure has shown the state in which a coupling member is located in a 2nd position. It is a perspective view of the hand-held tool provided with the connection part which concerns on 4th Embodiment. This figure shows a state in which the left side of the rear case is removed and the coupling portion is exposed. This figure shows a state in which the coupling member is located at the second position. It is a side view of the hand-held tool provided with the connection part which concerns on 4th Embodiment. This figure shows a state in which the left side of the rear case is removed and the coupling portion is exposed. This figure shows a state in which the coupling member is located at the second position.

  Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 5 show a hand-held tool 1 according to a first embodiment of the present invention. In the first embodiment, a disc grinder is illustrated as the hand-held tool 1. The hand-held tool 1 includes 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 is set to a thickness that is easy for a user to hold with one hand and functions as a grip portion.

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

  A gear head portion 4 is coupled to the front side of the main body portion 3. The gear head portion 4 includes a gear train (not shown in the figure) that decelerates the output of the electric motor 2 and outputs the reduced speed to the spindle 4a. The spindle 4 a is orthogonal 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 part of the spindle 4a. The rear side of the grindstone 5 is covered with a cover 6.

  The rear side of the main body 3 is covered with a rear case 7 having a left / right halved structure. FIG. 3 shows a state where the left half case 7a is removed. The left and right half cases 7a and 7b are coupled to each other by being screwed together by 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 abutting the left and right half cases 7a and 7b. A switch arm 10 is provided below the rear case 7 so as to be tiltable up and down via a support shaft 10a. A front end portion of the switch arm 10 is engaged with a rear portion of the switch lever 8. For this reason, the switch arm 10 tilts up and down in conjunction with the vertical movement of the switch lever 8. When the switch lever 8 is pulled upward, the rear portion thereof is displaced upward, and the switch arm 10 tilts upward (clockwise in FIG. 2). An operation convex portion 10 b is provided on the upper surface of the switch arm 10. The operation convex portion 10 b is disposed to face the operation button 9 a of the main switch 9. For this reason, when the switch arm 10 is tilted upward, the operation button 9a is pushed upward by the operation convex portion 10b and the main switch 9 is turned on.

  A large number of air inlets 7 c for introducing outside air are provided on the rear surface and the left and right side portions of the rear case 7. Although not visible in the figure, 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 air inlet 7c. The electric motor 2 is mainly cooled by the introduced outside air (motor cooling air). The motor cooling air is exhausted from the vicinity of the joint between the main body 3 and the gear head 4.

  In the present embodiment, an AC power source handheld tool 1 is illustrated. One power cord 11 is drawn from the rear surface of the rear case 7. AC power is supplied through the power cord 11.

  The hand-held tool 1 according to the first embodiment includes a coupling portion 15 for coupling a hanging tool S such as a tether strap for preventing falling during work. The coupling part 15 according to the first embodiment holds the coupling member 16 provided in the rear case 7 so as to be displaceable between the first position and the second position, and the coupling member 16 in the first position. For this purpose, a tension spring 17 is provided as a first position holding member.

  As shown in FIGS. 2 and 3, an inverted U-shaped frame 18 is attached to the lower surface of the rear portion of the rear case 7 and above the switch arm 10. The frame body 18 is sandwiched between the left and right half cases 7a and 7b and is assembled so as not to be displaced. As shown in the figure, the frame 18 also has a left / right halved structure. The coupling member 16 is supported by the frame 18 so as to be slidable back and forth.

  The coupling member 16 includes an annular hooking portion 16a at the rear portion. The hooking portion 16a protrudes rearward of 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 coupled to the hooking portion 16a.

  A tension spring 17 is interposed between the frame 18 and the coupling member 16. A front spring pin 18 a is provided at the front portion of the frame body 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 is hooked on the rear spring pin 16b. The tension member 17 holds the coupling member 16 in the first position shown in FIG. As shown in FIG. 2, the first position is a displaceable front end position of the coupling member 16. For example, the first position is regarded as a position where the hooking portion 16 a abuts the rear portion of the frame body 18 and cannot be displaced further forward. be able to. A semicircular recess 18b for allowing the screwing portion 7d to escape is provided at the rear portion of the frame 18. The hooking portion 16a comes into contact with the concave portion 18b and the front end position of the coupling member 16 is regulated.

  An escape recess 16 c for allowing the recess 18 b of the frame 18 to escape is provided on the upper portion of the coupling member 16. The relief 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 a range in which the recess 18b can be relatively displaced in the escape recess 16c. The front end position of the coupling member 16 in the range in which the front and rear direction can be displaced is set to the first position, and the rear end position is set to the second position.

  When an impact such as a drop is applied to the coupling member 16 via the hanging tool S, the coupling member 16 is displaced rearward against the urging 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. Therefore, 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, the tension spring 17 corresponds to a first position holding member.

  If the impact applied to the coupling member 16 via the hanging tool 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 is displaced to the second position. The second position corresponds to a retreat end position in which the recess 18b of the frame 18 comes into contact with the front end of the escape recess 16c and cannot be further retracted. As shown in FIG. 4, when the coupling member 16 is displaced to the second position, the indicator 16d for notification provided on the side surface can be visually confirmed. By visually checking 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, since the tension spring 17 is plastically deformed beyond the elastic region, the coupling member 16 is held at the second position even after the impact is removed. Thereby, it is reliably notified 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 convex portion 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 a higher abutment portion 10c. When the coupling member 16 is displaced to the second position, the restricting convex portion 16e is put on the contact base portion 10c. In this state, the displacement of the switch arm 10 to the on position side is restricted, and therefore the switch lever 8 cannot be pulled upward. Therefore, in a state where 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 handheld tool 1 becomes unusable.

  According to the coupling part 15 of the first embodiment described above, the hanging 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. The A state in which the coupling member 16 is located at the first position is a normal state of the coupling portion 15, and a sufficient hanging function of the hanging tool S is exhibited in this normal state.

  When an impact is applied to the coupling member 16 via the hanging tool 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 coupling member 16 to the second position, it is visually notified to the surroundings that the coupling 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 informing that the coupling portion 15 is damaged, the operator recognizes that it is necessary to perform maintenance such as replacement of the tension spring 17 or the coupling member 16 as the first position holding member. Accordingly, the hanging function of the hanging tool S (the function of the coupling portion 15) can be surely exhibited.

  In addition, the coupling member 16 is displaced to the second position by the plastic deformation of the tension spring 17 as the first position holding member. Since the tension spring 17 is plastically deformed beyond the elastic region, the coupling member 16 is held at the second position without being returned to the first position once it is displaced to the second position. From this, in the coupling part 15 according to the first embodiment, the tension spring 17 as the first position holding member also functions as a second position holding member for holding the coupling member 16 in the second position. The coupling member 15 is damaged by the displacement of the first position being restricted by the tension spring 17 that also functions as the second position holding member and being held at the second position. Is notified more reliably.

  By performing maintenance such as replacing the plastically deformed tension spring 17, the coupling member 16 can be returned to the normal state held in the first position again. It can be used in the state.

  Further, according to the coupling portion 15 of the first embodiment, when the coupling member 16 is displaced to the second position by the impact received through the hanging tool S, the displacement of the switch arm 10 to the on side is restricted. The switch lever 8 cannot be pulled and the activation of the electric motor 2 is restricted. Since the main body 3 cannot be activated in this way, it is more reliably notified that the coupling portion 15 has been damaged, and the use of the handheld tool 1 in a state where the coupling portion 15 has been damaged is prevented. Avoided.

  In FIG. 6 and subsequent figures, a connecting portion 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 that holds the coupling member 21 in the first position, and the coupling member 21. 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 second position at the second position. About the member and structure which do not require a change, the description is abbreviate | omitted using a same sign.

  The coupling member 21 according to the second embodiment is supported by a reverse U-shaped frame 18 assembled on the lower surface side of the rear case 7 so as to be slidable back and forth. An annular hook portion 21 a is provided at the rear portion of the coupling member 21. The hook portion 21 a protrudes rearward from the rear surface of the rear case 7. A hanging tool S such as a tether strap is coupled to the hook portion 21a.

  The coupling member 21 is coupled to the frame 18 by a 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 disengaged from one of the coupling member 21 and the frame body 18, the coupling member 21 is displaced to the second position behind the frame body 18.

  An engagement shaft 23 is supported on the upper surface of the coupling member 21 so as to be vertically displaceable. The engagement shaft 23 is urged by a compression spring 24 in a direction protruding upward. As shown in FIGS. 6 and 7, in a state where the coupling member 21 is located at the first position, the engagement shaft 23 is abutted against the upper portion of the frame 18 and is in a retracted position where it does not project from the upper surface of the coupling member 21. Is retained. An engagement hole 18 c is provided in the upper portion of the frame body 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. As a result, the engagement shaft 23 is moved into the engagement hole 18c by the compression spring 24. Protruding state. When the engagement shaft 23 protrudes into the engagement hole 18c, the engagement member 21 is held at the second position, and the return operation to the first position is restricted.

  As in the first embodiment, the coupling member 21 is provided with a regulation convex portion 21b, a relief concave portion 21c, and an indicator 21d. As shown in FIG. 9, when the engaging member 21 is displaced to the second position, the restricting convex portion 21 b is placed on the contact base portion 10 c of the switch arm 10, and the switch lever 8 cannot be pulled. Therefore, the electric motor 2 cannot be started. The screw recess 7d and the recess 18b of the frame 18 for allowing the screw stopper 7d to escape enter the escape recess 21c. The coupling member 21 can be displaced in the front-rear direction within a range in which the screwing portion 7d and the concave portion 18b can be displaced and relatively displaced in the concave portion 21c. As shown in FIGS. 6 and 7, when the coupling member 21 is located at the first position, the hooking portion 21a is in contact with the recess 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 end portions 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 body 18, respectively, and the coupling member 21 is held at the first position. In a normal state where the coupling member 21 is held at the first position and the suspension member S can fully perform the suspension function, the switch lever 8 is pulled and operated as shown in FIG. The switch 9 can be turned on, so that the handheld tool 1 can be used.

  As shown in FIG. 9, when a large impact is applied to the coupling member 21 through the hanging tool S, as a result, the shaft member 22 is disengaged from the engagement hole 18d and the coupling member 21 is displaced to the second position, the indicator 21d is It is reliably notified by the surroundings that the connecting member 21 is exposed and displaced to the second position.

  According to the coupling part 20 of the second embodiment described above, the suspending 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. The The state in which the coupling member 21 is located at the first position is a normal state of the coupling portion 20, and a sufficient hanging function of the hanging tool S is exhibited in this normal state.

  When an impact is applied to the coupling member 21 through the hanging 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 coupling member 21 to the second position, the surroundings are informed that the coupling portion 20 has been damaged. By notifying that the joint portion 20 has been damaged in this manner, the necessity of maintenance of the joint portion 20 is notified, and as a result, the suspension function of the joint portion 20 is fully exhibited.

  In the second embodiment, after the coupling member 21 is once displaced to the second position, the engagement shaft 23 enters the engagement hole 18c and is held at the second position. Thus, the return to the position is regulated so that the fact that the connecting portion 20 is damaged can be more reliably notified.

  Furthermore, also in the second embodiment, when 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 therefore the handheld tool 1 cannot be used. . Thereby, it is reliably notified that the connecting portion 20 has been damaged, and the necessity of maintenance is notified.

  In the coupling portion 20 of the second embodiment, maintenance can be performed by exchanging the shaft member 22, the frame 18 and the like, so that the coupling member 21 can be returned to the normal state held at the first position again. By performing necessary maintenance, the connecting portion 20 can be used again in a normal state.

  10 to 12 show a coupling portion 30 according to the third embodiment. The coupling unit 30 of the third embodiment has a configuration in which a power supply circuit cutoff function is added to the coupling unit 20 of the second embodiment. Explanations of members and configurations that do not need to be changed will be omitted using the agreement.

  In the third embodiment, a circuit conduction portion 31 is interposed between the frame 18 and the coupling member 21. The circuit conduction part 31 includes contact parts 31a and 31b attached to the frame body 18 side and a conduction part 31c attached to the coupling member 21 side. A conductive plate obtained by bending a conductive strip 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 an elastic force on the closed side. The end portion of the conducting portion 31c is elastically sandwiched between the contact portions 31a and 31b and is held in a connected state. As shown in FIG. 10, in a normal state where the coupling member 21 is located at the first position (a state in which a sufficient hanging function is exhibited), both end portions of the conducting portion 31c are inserted into the contact portions 31a and 31b, respectively. The two contact portions 31a and 31b are electrically connected through one conductive portion 31c. The power supply circuit is brought into a conductive state by electrically connecting the contact portions 31a and 31b, and the electric motor 2 is started by turning on the switch lever 8 in this conductive state.

  As shown in FIG. 11, when the impact is applied to the coupling member 21 through the hanging tool S and the shaft portion 22 is detached from the frame 18 or the coupling member 21, and as a result, the coupling member 21 is displaced to the second position side, The conducting part 31c is disengaged from both contact parts 31a and 31b. Both end portions of the conducting portion 31c are displaced rearward against the elastic pinching force of the contact portions 31a and 31b (displacement of the contact portions 31a and 31b in the opening direction) and disengage from the contact portions 31a and 31b. . When the conducting part 31c is detached from the contact parts 31a and 31b, the conduction between the both contact parts 31a and 31b is lost, so that the power supply circuit is cut off.

  In a state where 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 main switch 9 is turned on by pulling the switch lever 8. As described above, in the third embodiment, when the coupling member 21 is displaced to the second position, the power supply circuit is cut off, so that the electric motor 2 cannot be started. Therefore, the first and second embodiments are exemplified. The restricting convex portions 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 regulating projections 16e and 21b abut on the abutment base 10c, so that the on-side tilting operation of the switch arm 10 and the on-operation of the switch lever 8 are prohibited. Thus, the start of the electric motor 2 is avoided. On the other hand, in the third embodiment, although the tilting operation of the switch lever 8 is possible, the configuration is such that the activation of the electric motor 2 is avoided by cutting off the power supply circuit, and as a result, the switch lever 8 is different from the first and second embodiments in that the on operation is invalidated.

  Also by the coupling part 30 of the third embodiment described above, a large impact is applied to the coupling member 21 via the suspending tool S, and the coupling member 21 is displaced to the second position, so that the coupling part 30 is displaced. The surroundings are informed that they have been damaged. Moreover, it can confirm visually reliably by the indicator 21d exposed when the coupling member 21 displaces to a 2nd position. Also, 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, thereby In addition, it is reliably notified that the coupling portion 30 has been damaged.

  Also in the third embodiment, it is notified that the coupling portion 30 has been damaged due to the displacement of the coupling member 21, whereby the user stops using the hand-held tool 1 or performs maintenance of the coupling portion 30. Thus, a reliable hanging function of the coupling portion 30 can be exhibited.

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

  The handheld tool 1 of 4th Embodiment is shown by FIGS. 13-21. Since the basic configuration of the hand-held tool 1 does not need to be changed, description thereof is omitted using the same sign. In 4th Embodiment, the structure different from the 1st-3rd embodiment is provided about the coupling | bond part 40 for couple | bonding hanging tools S, such as a tether strap. There is no need to change the basic configuration of the handheld tool 1. About the member and structure which do not require a change, the description is abbreviate | omitted using a same sign.

  The coupling portion 40 of the fourth embodiment is disposed on the upper surface of the rear case 7 and above the power cord 11. Details of the connecting portion 40 of the fourth embodiment are shown in FIGS. The coupling portion 40 of the fourth embodiment includes a coupling member 41 for coupling a hanging tool S such as a tether strap, a first position holding member 42 for holding the coupling member 41 in a first position, A second position holding member for holding the member 41 in the second position and an engagement shaft 44 for restricting the retracted 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 includes a pair of left and right engaging arms 42a. The rear side of the pair of left and right engaging arms 42a is bent in an L shape on the side approaching each other to form a bent portion 42b. Both engagement arms 42a have an elastic force in a direction in which the bent portions 42b on the rear side approach each other. Both engagement arms 42 a are attached to the left and right side surfaces of the pedestal portion 43 in parallel with each other. The pedestal portion 43 is fixed to the rear case 7 side and thus to the main body portion 3 side.

  The pair of left and right engaging arms 42a are closed by overlapping the rear bent portions 42b by elastic force, so that the coupling member 41 is in the first position (the bent portion 42b is positioned on the inner peripheral side). ). 13, FIG. 14, FIG. 16, and FIG. 18 each show a normal state in which the coupling member 41 is held in 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 engagement arms 42a. When an external force in the push-open direction (rearward direction) is applied to both bent portions 42b through the coupling member 41, both the engaging arms 42a are displaced in a direction away from each other against the elastic force, and both bent portions 42 The overlapping state of 42b is opened. When the engagement arm 42a is pushed 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 located on the inner peripheral side of the coupling member 41. The engagement 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 displaces backward, the engagement shaft 44 restricts further backward movement. It becomes. The retracted end position regulated by the engagement shaft 44 corresponds to the second position. The state where the coupling member 41 is displaced to the second position is shown in FIGS. 15, 17, 19, 20, and 21.

  When the coupling member 41 is displaced from the first position to the second position, the pair of left and right engaging arms 42a are returned to a direction in which they approach each other by their own elastic force. When the pair of left and right engaging arms 42a are 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 way, the coupling member 41 once displaced to the second position is prevented from returning 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 in the first position, and holds the coupling member 41 in the second position. It also has a function as a second position holding member for preventing it from returning to the first position.

  By holding the coupling member 41 in the state displaced to the second position by the pair of left and right engaging arms 42a as the second position holding member, it is notified to the surroundings that the coupling portion 40 has been damaged. Therefore, the necessity of maintenance of the connecting portion 40 is notified. As described above, the coupling member 41 in which the pair of left and right engaging arms 42a are closed and held at the second position is rattling within a range where the coupling member 41 is not returned to the first position and is not engaged with the engaging shaft 44. , It is possible to displace forward and backward, and this also informs that the joint 40 has been damaged.

  In the case of the fourth embodiment, the coupling member 41 can be returned to the first position by removing the rear case 7 and opening the left and right engagement arms 42a. For this reason, in 4th Embodiment, the said connection part 40 can be returned to a normal state, without replacing components, such as the engagement arm 42a, and this point differs from 1st-3rd Embodiment. Yes.

  According to the coupling portion 40 of the fourth embodiment described above, in the normal state where the coupling member 41 coupled with the hanging tool S is held at the first position, the hanging tool S causes the handheld tool 1 to be unfit. Prepared fall is prevented. When a large impact is applied to the coupling portion 40 via the hanging tool S when falling is prevented, the coupling member 41 is damaged by the displacement of the coupling member 41 to the second position. Visually informed. By confirming that the coupling member 41 has been displaced to the second position, the user can recognize the necessity of maintenance for the coupling portion 40 and determine that the subsequent use should be temporarily stopped. Can do.

  In 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, and as described above, it is not necessary to replace parts as in the first to third embodiments. In the fourth embodiment, the pair of left and right engagement arms 42a is illustrated, but the coupling member 41 may be held at the first position by the engagement arm only on one side.

  Each embodiment described above can be further modified. The configuration in which the coupling portions 15, 20, 30, and 40 that couple the hanging tool S such as a tether strap are provided at the rear portion of the hand-held tool 1 is illustrated, but the configuration may be provided at the side portion or the front portion.

  Although the disc grinder has been exemplified as the hand-held tool 1, the exemplified coupling portion can be applied to other drilling tools such as a hammer drill and other electric tools or power tools such as a cutting machine. Moreover, although the AC power supply type hand-held tool 1 has been illustrated, the coupling portion illustrated for the rechargeable hand-held tool that uses a battery pack that can be repeatedly used by charging as a power source can be applied.

S ... Hanging tool 1 ... Hand tool (disc grinder)
2 ... Electric motor 3 ... main body 3a ... main body housing 4 ... gear head 4a ... spindle 5 ... grinding stone 6 ... cover 7 ... rear case 7a ... left half case 7b ... right half case 7c ... inlet, 7d ... Screw fixing part 8 ... Switch lever 9 ... Main switch, 9a ... Actuation button 10 ... Switch arm 10a ... Support shaft, 10b ... Actuation convex part, 10c ... Abutment base part 11 ... Power cord 15 ... Coupling part (first Embodiment)
DESCRIPTION OF SYMBOLS 16 ... Coupling member 16a ... Hook part, 16b ... Rear side spring pin, 16c ... Escape recessed part 16d ... Indicator, 16e ... Restriction convex part 17 ... Tension spring (1st position holding member / 2nd position holding member)
18 ... Frame 18a ... Front spring pin, 18b ... Recess, 18c ... Engagement hole, 18d ... Engagement hole 20 ... Coupling part (second embodiment)
21 ... Coupling member 21a ... Hooking part, 21b ... Restriction convex part, 21c ... Escape concave part, 21d ... Indicator 22 ... Shaft member (first position holding member)
23 ... engaging shaft (second position holding member)
24... Compression spring 30... Joint (third embodiment)
31 ... Circuit conduction part, 31a, 31b ... Contact part, 31c ... Conduction part 40 ... Coupling part (4th Embodiment)
41 ... coupling member 42 ... first position holding member 42a ... engagement arm 42b ... bent portion 43 ... pedestal portion 44 ... engagement shaft

Claims (6)

A hand-held tool used by a worker to hold in a hand, and having a coupling part for coupling a hanging tool, the coupling part between a first position and a second position with respect to the housing And a first position holding member for holding the coupling member in the first position, and the coupling member is moved to the second position by deformation of the first position holding member. A hand-held tool that is configured to be displaced to a position and to restrict activation of the main body. 2. The hand-held tool according to claim 1, wherein the power supply circuit is cut off and activation of the main body is restricted. The hand-held tool according to claim 2, wherein a conductive portion is provided on the coupling member, a contact portion is provided on a frame body that supports the coupling member, and the conductive portion and the contact portion are provided in the power supply circuit. A circuit conduction portion that is conducted by contact is provided, the conduction portion and the contact portion are contacted at the first position, the circuit conduction portion is conducted to be in a power supply state, and the conduction at the second position. A hand-held tool configured to shut off the power supply circuit when a portion is separated from the contact portion and the circuit conduction portion is in a non-conduction state. 4. The hand-held tool according to claim 3, wherein the conductive portion is held in contact by elastic pinching of the contact portion, and the conductive portion is separated by displacing the contact portion against elastic force. tool. 5. The hand-held tool according to claim 1, wherein in a state where the coupling member is displaced to the second position, an on operation of the switch lever is restricted and activation of the main body is restricted. Hand-held tool with a configured structure. The hand-held tool according to any one of claims 1 to 5, wherein the coupling member is configured to be restricted from being displaced to the first position after being displaced to the second position. tool.

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