JP7153541B2 - Rotary tool and engaging member provided therewith - Google Patents

Description

The present invention relates to a rotary tool such as an impact wrench for tightening screws such as bolts and nuts.

2. Description of the Related Art In a process of assembling automobiles and the like, workers sometimes use rotary tools such as impact wrenches to tighten bolts and nuts. A rotary tool used in such an assembly process is generally capable of adjusting the rotation speed of a motor according to the amount of operation (pull-in amount) of a trigger. That is, the motor rotates at a low speed when the amount of trigger retraction is small, and the rotational speed of the motor increases as the amount of retraction of the trigger increases.

When tightening a bolt using a rotating tool such as the one described above, if the bolt and the screw hole are not set coaxially, seizure (screw galling) will occur. When screw galling occurs, the thread must be repaired, and since severe screw galling cannot be repaired, parts must be replaced, both of which increase man-hours and material costs. In order to avoid such problems, in the initial stage of bolt tightening, the operator maintains the trigger with a small retraction amount and rotates the motor at a low speed, while adjusting the attitude of the rotary tool so that the bolt and the threaded hole are aligned. are arranged coaxially, and the screws of both must be meshed. However, such work is not easy. In particular, depending on the location, you may not be able to face the bolt mounting surface, or you may have to work with a rotary tool with your non-dominant hand. However, it is extremely difficult to hold the rotary tool in a predetermined position and properly mesh the bolt with the screw hole, and requires skill.

For example, in the rotary tool disclosed in Patent Document 1 below, the motor rotates at a low speed during an initial drive period until a predetermined time elapses after the motor starts to rotate, and after the initial drive period has elapsed, the motor rotates at a high speed. controlled to automatically switch to rotation. In this case, since it is not necessary to keep the trigger with a small retraction amount at the initial stage of bolt tightening, the bolt tightening work becomes easier.

JP 2016-78230 A

However, when controlling the switching from low-speed to high-speed rotation of the motor by time as described above, if the bolt cannot be properly engaged with the screw hole during low-speed rotation, the motor will automatically switch to high-speed rotation. Since it is switched, there is a risk of screw galling. In addition, in order to control the rotational speed of the motor by time as described above, it is necessary to change the control program of the motor, etc., which is costly.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to reliably prevent screw galling and to facilitate tightening operations of screws using a rotating tool while reducing costs.

In order to solve the above-mentioned problems, the present invention provides a rotary tool comprising a main body having a motor, and a drive switch provided slidably with respect to the main body and changing the rotation speed of the motor according to the amount of sliding. and
A rotary tool is provided in which the drive switch and the main body are provided with engaging portions that engage with each other in the sliding direction when the sliding amount of the drive switch reaches a predetermined value smaller than the maximum value.

In this rotary tool, when the drive switch is operated and the amount of slide reaches a predetermined value, the engagement portion provided on the main body and the engagement portion provided on the drive switch are engaged with each other, whereby the drive switch is operated. is given resistance. By holding the drive switch at a position where resistance is felt, the operator can easily maintain the motor rotating at a low speed. In this case, costs can be reduced because there is no need to change the control program. In addition, since the operator can voluntarily slide the drive switch step by step, it is possible to prevent the rotation speed of the motor from automatically switching to a high speed, thereby preventing the occurrence of screw galling.

The main body of the rotary tool is sometimes provided with a switching lever for switching the rotation direction of the motor between the forward direction for tightening the screw and the reverse direction for loosening the screw. If the switching lever is provided with the engaging portion on the main body side, the number of parts can be reduced and the cost can be reduced as compared with the case where a separate member having the engaging portion is provided.

After confirming that the screws are properly engaged, the operator releases the engagement between the engaging portion on the drive switch side and the engaging portion on the main body side, and further increases the amount of sliding of the drive switch to allow the motor to operate. can be rotated at high speed. At this time, by using the play provided in the support mechanism for supporting the sliding of the drive switch, the drive switch is moved in a direction orthogonal to the sliding direction, thereby releasing the engagement between the two engaging portions. If so, the mechanism for releasing the engagement between the two engaging portions can be simplified.

For example, a drive switch for a general rotary tool comprising a main body having a motor and a drive switch provided slidably with respect to the main body for changing the rotational speed of the motor according to the amount of sliding may include the drive switch. If an engaging member having an engaging portion that engages with the engaging portion provided on the main body in the sliding direction when the sliding amount of the switch reaches a predetermined value smaller than the maximum value, the present invention can be applied. A rotary tool as described above can be obtained.

As described above, in the rotary tool of the present invention, the rotation speed of the motor is not automatically switched by control, but the amount of slide of the drive switch, that is, the rotation speed of the motor can be adjusted by the operator's intention. It is possible to reliably prevent screw galling while suppressing costs. In addition, the drive switch can be easily held by a predetermined amount of sliding due to the mechanical engagement between the engaging portion on the drive switch side and the engaging portion on the main body side. become.

It is a side view of a rotary tool. FIG. 4 is a partially cross-sectional side view of a drive switch mechanism provided in the rotary tool; It is a top view of the said drive switch mechanism, and shows the state which restricts rotation of a motor. It is a top view of the said drive switch mechanism, and shows the state which rotates a motor forward (direction to tighten a screw). It is a top view of the said drive switch mechanism, and shows the state which rotates a motor in a reverse direction (direction to loosen a screw). FIG. 5 is a top view of the drive switch mechanism of FIG. 4, showing a state in which the engaging member of the trigger and the engaging portion of the switching lever are engaged; 7 shows a state in which the trigger of the drive switch mechanism of FIG. 6 is further pulled; 8 shows a state in which the trigger of the drive switch mechanism of FIG. 7 is further pulled; It is a top view of an engaging member concerning other embodiments. FIG. 11 is a top view of an engaging member according to still another embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

An impact wrench 1 as a rotary tool according to this embodiment mainly includes a main body 10 and a battery 20 detachable from the main body 10, as shown in FIG. Inside the case 11 of the main body 10 are a motor 12, a deceleration mechanism 13 for decelerating the rotation of the motor 12, a striking mechanism 14 for applying an impact force to the rotation output from the deceleration mechanism, and a controller for controlling the rotational speed of the motor 12. A control unit 15 is provided. Various tools (for example, a socket 30) are attached to the output shaft of the striking mechanism 14. As shown in FIG. In this embodiment, as shown in FIG. 1, the main body is arranged so that the rotation axis direction of the motor 12 (hereinafter referred to as "motor axis direction") is horizontal, the motor 12 is on the upper side, and the battery 20 is on the lower side. Each part will be explained with 10 arranged. At this time, the direction perpendicular to both the motor shaft direction (horizontal direction in FIG. 1) and the vertical direction (direction perpendicular to the paper surface of FIG. 1) is called the width direction.

The impact wrench 1 has a drive switch mechanism 40 operated by an operator. The drive switch mechanism 40 includes a switch body 41 fixed to the case 11 of the main body 10, a trigger 42 as a drive switch provided slidably in the motor shaft direction with respect to the main body 10, and a width direction with respect to the main body 10. and a changeover switch 43 slidably provided in. The trigger 42 protrudes forward (to the left in FIG. 1) from the case 11 of the main body 10, and the selector switch 43 protrudes from the case 11 of the main body 10 on both sides in the width direction.

As shown in FIG. 2, the switch body 41 includes a housing 41a, a slide shaft 41b attached to the housing 41a so as to reciprocate in the motor shaft direction, and a slide shaft 41b attached to the housing 41a so as to rotate vertically. and a rotating shaft 41c. Inside the housing 41a, there are provided a bearing 41d that supports the slide shaft 41b, a slide amount detector 41e that detects the slide amount of the slide shaft 41b, and a switching sensor 41f that switches depending on the rotation angle of the rotation shaft 41c. A support mechanism for supporting the slide of the trigger 42 is configured by the slide shaft 41b and the bearing 41d. The slide shaft 41b is biased by biasing means (not shown) toward the side projecting forward from the housing 41a, that is, toward the side that causes the trigger 42 to retreat (left side in FIG. 2).

The trigger 42 has a body portion 42a to be pressed by an operator, an attachment portion 42b attached to the slide shaft 41b of the switch body 41, and a locking piece 42c. In this embodiment, the main body portion 42a, the attachment portion 42b, and the locking piece 42c are integrally molded with resin.

The operator draws in the trigger 42 against the urging force of the urging means and slides it toward the switch body 41 (right side in FIG. 2) to rotate the motor 12 . The amount of slide of the trigger 42 at this time, that is, the amount of slide of the slide shaft 41b is detected by the slide amount detection unit 41e, and the signal is transmitted to the control unit 15. to rotate. Specifically, when the amount of slide of the trigger 42 exceeds a predetermined value, the rotation of the motor 12 is started. When the maximum value is reached, the rotation speed of the motor 12 becomes maximum.

A switching lever 44 is attached to the rotary shaft 41 c of the switch body 41 . The switching lever 44 has a lever body 44a, a pin 44b projecting upward from the lever body 44a, and an engaging portion 44c extending downward from the tip of the lever body 44a. In the illustrated example, the lever body 44a, the pin 44b, and the engaging portion 44c are integrally molded of resin. A pin 44 b of the switching lever 44 is inserted into an elongated hole 43 a provided in the switching switch 43 . The change-over switch 32 and the change-over lever 44 have a rotation restriction position (see FIG. 3) that restricts the rotation of the motor 12, a forward rotation position (see FIG. 4) that rotates the motor 12 in the forward direction, and a forward rotation position (see FIG. 4) that rotates the motor in the reverse direction. It is movable between a reverse rotation position (see FIG. 5) that allows

As shown in FIG. 3, when the change-over switch 43 is placed at the rotation restricting position, the engagement portion 44c of the change-over lever 44 and the locking piece 42c of the trigger 42 face each other in the sliding direction and are engaged. As a result, the pull-in operation of the trigger 42 (slide to the side approaching the switch body 41) is restricted. At this time, by engaging the engaging piece 42c of the trigger 42 with the engaging portion 44c of the switching lever 44 before the rotation of the motor 12 starts, the rotation of the motor 12 is restricted.

When the change-over switch 43 is slid to the forward rotation position shown in FIG. 4, the elongated hole 43a of the change-over switch 43 and the pin 44b of the change-over lever 44 are engaged with each other, causing the change-over lever 44 to rotate about the rotation shaft 41c. Rotate clockwise. At this time, the rotation of the rotating shaft 41c activates the switching sensor 41f of the switch body 41, the signal is transmitted to the control unit 15, and the rotation direction of the motor 12 is set to the positive direction (the direction in which the screw is tightened). . At this time, the engaging portion 44c of the switching lever 44 is displaced to one side in the width direction with respect to the locking piece 42c of the trigger 42, and is disposed at a position where it does not engage in the sliding direction, so that the trigger 42 can slide. It is in a good state. Therefore, when the operator pulls in the trigger 42, the motor 12 rotates in the forward direction.

When the change-over switch 43 is slid to the reverse rotation position shown in FIG. 5, the change-over lever 44 rotates clockwise around the rotating shaft 41c. At this time, the rotation of the rotating shaft 41c activates the switching sensor 41f of the switch body 41, the signal is transmitted to the control unit 15, and the rotation direction of the motor 12 is reversed (in the direction of loosening the screw). . At this time, the engaging portion 44c of the switching lever 44 is shifted to the other side in the width direction with respect to the locking piece 42c of the trigger 42, and is disposed at a position where it does not engage in the sliding direction, so that the trigger 42 can slide. It is in a good state. Therefore, when the operator pulls in the trigger 42, the motor 12 rotates in the opposite direction.

The basic configuration of the impact wrench 1 has been described above, and the engaging member 45, which is a characteristic configuration of the present invention, will be described below.

As shown in FIGS. 2 and 3, the trigger 42 is provided with an engaging member 45 . The engaging member 45 is accommodated in the main body portion 42a of the trigger 42, and fixed to the locking piece 42c by an appropriate means such as adhesion. The engaging member 45 has an engaging surface 45a as an engaging portion that engages in the sliding direction with the engaging portion 44c of the switching lever 44 arranged at the forward rotation position shown in FIG. The engaging surface 45a is, for example, a flat surface orthogonal to the sliding direction. In the illustrated example, a locking piece 42c is provided at the center in the width direction of the body portion 42a of the trigger 42, and an engagement surface 45a is provided on one side in the width direction. Between the engaging member 45 and the side wall of the body portion 42a of the trigger 42, a widthwise gap G is provided in which the engaging portion 44c of the switching lever 44 can enter.

When the trigger 42 is pulled in with the switching lever 44 placed in the forward rotation position shown in FIG. After that, as the amount of retraction of the trigger 42 increases, the rotational speed of the motor 12 gradually increases. Then, as shown in FIG. 6, when the engaging surface 45a of the engaging member 45 provided on the trigger 42 contacts the engaging portion 44c of the switching lever 44, resistance is applied to the operation of the trigger 42, and the trigger 42 stops (this position is called an "intermediate position"). At this time, the position of the engaging surface 45a is set so that the rotation speed of the motor 12 is sufficiently low (for example, 5 rotations/second or less).

In this way, by applying resistance to the operation of the trigger 42 through mechanical engagement between the engaging member 45 and the switching lever 44, the operator can easily hold the trigger 42 at an intermediate position where there is resistance. be able to. As a result, the motor 12 can be rotated at a low and constant speed without the need for a highly difficult operation to hold the trigger 42 at a delicate position. facilitated.

When the operator confirms that the screw of the bolt and the screw of the threaded hole are properly engaged, the engagement between the engaging member 45 of the trigger 42 and the engaging portion 44c of the switching lever 44 is released. The trigger 42 is pulled further than the intermediate position. In this embodiment, the engagement between the engaging member 45 of the trigger 42 and the engaging portion 44c of the switching lever 44 is released by pulling the trigger 42 with a force greater than or equal to a predetermined force. Specifically, between the support mechanism that supports the slide of the trigger 42, that is, the slide shaft 41b of the switch body 41 and the bearing 41d (see FIG. 2) that supports the slide shaft 41b, a direction perpendicular to the slide direction (radial direction) is provided. ) is provided, and this play can be used to move the trigger 42 in a direction perpendicular to the sliding direction (in the illustrated example, in the width direction). When the operator pulls in the trigger 42 while it is engaged with the engaging portion 44c of the switching lever 44, the trigger 42 moves to the other side in the width direction (upper side in the drawing) while the slide shaft 41b is tilted. The engagement between the engaging surface 45a of the joining member 45 and the engaging portion 44c of the switching lever 44 is released (see FIG. 7).

When the trigger 42 is further pulled in, the engaging portion 44c of the switching lever 44 is fitted into the gap G between the engaging member 45 and the side wall of the body portion 42a of the trigger 42, as shown in FIG. This causes the trigger 42 to slide past the intermediate position and the motor 12 to rotate at high speed. Then, when the bolt is tightened to a predetermined position, a torque greater than a predetermined amount is applied to the motor 12, and the rotation of the motor 12 is stopped by detecting this torque.

On the other hand, when the switching lever 44 is placed in the reverse rotation position (see FIG. 5), the engaging surface 45a of the engaging member 45 and the engaging portion 44c of the switching lever 44 are misaligned in the width direction from the beginning. They do not engage in the sliding direction, and the trigger 42 can be pulled up to the maximum without resistance. Since the motor 12 needs to be maintained at low speed only when tightening the screw (i.e., when rotating in the forward direction), engagement of the trigger 42 is required for reverse rotation as described above. By reducing the resistance when operating the trigger 42 without engaging the member 45 and the engaging portion 44c of the switching lever 44, the burden on the operator is reduced.

The invention is not limited to the above embodiments. Duplicate descriptions of the same points as in the above-described embodiment will be omitted.

The shape of the engaging member 45 is not limited to the above. Thereby, the engaging member 45 can be fixed to the trigger 42 more firmly. Specifically, the engaging member 45 includes a first portion 45b provided on one widthwise side (lower side in the drawing) of the locking piece 42c and a first portion 45b provided on the other widthwise side (upper side in the drawing) of the locking piece 42c. It consists of a second portion 45c provided and a third portion 45d connecting the first portion 45b and the second portion 45c. An end surface 45b1 of the first portion 45b on the main body side (right side in the drawing) functions as an engaging surface 45a that engages with the engaging portion 44c of the switching lever arranged in the forward rotation position. The body-side end surface 45c1 of the second portion 45c has a smaller width dimension than the body-side end surface 45b1 of the first portion 45b. As a result, the end surface 45c1 of the second portion 45c does not engage with the engaging portion 44c of the switching lever arranged in the reverse rotation position, or even if engaged, the trigger 42 is slightly displaced to one side in the width direction. , the engagement is released.

In the embodiment shown in FIG. 10, the engaging surface 45a of the engaging member 45 is an inclined surface that is inclined toward the side (left side in the drawing) on which the trigger 42 retreats toward one side in the width direction (lower side in the drawing). be. Accordingly, when the engaging portion 44c of the switching lever 44 is engaged with the engaging surface 45a of the engaging member 45, the engaging member 45 is easily moved to the other side in the width direction (upper side in the drawing). The pull-in force of the trigger 42 required for releasing the is reduced.

In the above embodiment, the case where the engaging member 45 and the trigger 42 are configured as separate members has been shown, but for example, these may be integrally molded with resin. Alternatively, an engaging member having the above functions may be provided on the main body side (for example, the switch main body 41) and engaged with the trigger 42 (for example, the locking piece 42c).

1 impact wrench (rotary tool)
10 Body 11 Case 12 Motor 13 Reduction Mechanism 14 Impact Mechanism 15 Control Unit 20 Battery 30 Socket 40 Drive Switch Mechanism 41 Switch Body 41b Slide Shaft 42 Trigger (Drive Switch)
42c Locking piece 43 Switching switch 44 Switching lever 44a Lever main body 44c Engaging portion 45 Engaging member 45a Engaging surface (engaging portion)

Claims (3)

A rotary tool comprising: a main body having a motor; and a drive switch slidably provided with respect to the main body for changing the rotation speed of the motor in accordance with a slide amount,
The driving switch and the main body are engaged with each other in the sliding direction when the sliding amount of the driving switch is gradually increased and reaches a predetermined value smaller than the maximum value, thereby increasing the forward rotational speed of the motor. provided with an engaging portion that regulates at a predetermined speed ,
By releasing the engagement between the engaging portion of the drive switch and the engaging portion of the main body and increasing the amount of sliding of the drive switch to be greater than the predetermined value, the rotational speed of the motor in the forward direction is increased. can be made higher than the predetermined speed . A switching lever for switching the rotation direction of the motor is provided on the main body,
2. The rotary tool according to claim 1, wherein the switching lever is provided with an engaging portion on the main body side. An engaging member attached to the drive switch of a rotary tool, comprising a main body having a motor, and a drive switch provided slidably with respect to the main body and changing the rotation speed of the motor according to the amount of sliding. hand,
When the amount of sliding of the drive switch reaches a predetermined value smaller than the maximum value , the forward rotation speed of the motor is increased to a predetermined speed by engaging with an engaging portion provided on the main body in the sliding direction. has an engaging portion that is regulated by
By releasing the engagement between the engaging portion of the drive switch and the engaging portion of the main body and increasing the amount of sliding of the drive switch to be greater than the predetermined value, the rotational speed of the motor in the forward direction is increased. is greater than the predetermined speed .

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