JP2011251357A - Impact rotary tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impact rotary tool capable of keeping such a state that an O-ring is always covered with a member covering the O-ring for preventing a connection pin from falling out.SOLUTION: The impact rotary tool includes: a square rotary shaft 16 that is protruded from a housing 11 for housing a driving part 12 and that is rotated by the operation of the driving part 12; a socket 20 having a square hole that is fitted to the square rotary shaft 16; a connection pin 19 that is inserted into the shaft through-hole 18 of the square rotary shaft 16 and the socket through-hole 23 of the socket 20 and that connects the socket 20 with the square rotary shaft 16; an annular groove 24 that is formed in the circumferential direction of the outer periphery of the socket 20 and that goes over the socket through-hole 23; an elastic ring that is installed in the annular groove 24; a cylindrical cover 26 that is loosely fitted to the socket 20 to cover the elastic ring of the annular groove 24; and an interposing member that is interposed between the cylindrical cover 26 in the rotary axial center P direction of the square rotary shaft 16 and the housing 11 side. The interposing member regulates movement of the cylindrical cover 26 to the housing 11 side.

Description

  The present invention relates to an impact rotary tool such as an impact wrench or an impact driver.

As a conventional impact rotary tool, for example, the rotary tool disclosed in Patent Document 1 can be cited.
In this rotary tool, the prism portion formed on the anvil of the rotary tool is inserted into the square hole formed on the base portion of the tool, and the connecting pin is inserted into the through hole penetrating the anvil and the tool in the direction perpendicular to the rotation axis. ing.
Then, an O-ring is attached to the outer peripheral surface of the tool so as to cover both end portions of the through hole, and a wide ring having a width wider than the width of the O-ring is attached on the O-ring.
According to this rotary tool, it is possible to increase the tightening force for suppressing the load in the pulling direction of the connecting pin, and to prevent the connecting pin from coming out of the through hole due to the centrifugal force.

Japanese Patent Laid-Open No. 2003-71735

By the way, when using this type of impact rotary tool, for example, an operator wearing a work gloves may grip the grip of the rotary tool with the right hand and operate the rotary tool with the left hand attached to the tool.
However, in the rotating tool disclosed in Patent Document 1, when the tool is rotated with a hand attached, the hand may hit the wide ring and the O-ring, and the elastic wide ring and the O-ring may come off and move. is there.
When the wide ring and the O-ring move to a position away from the through hole, the connecting pin comes out of the through hole due to the rotation of the tool.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an impact rotary tool that can maintain a state in which a member that covers an O-ring that prevents the connection pin from coming out always covers the O-ring. It is in.

  In order to solve the above-described problems, the present invention provides a housing that accommodates a drive unit, and a rectangular rotation that protrudes from the housing and is rotated by the operation of the drive unit, and has a square cross section that intersects the rotation axis. A shaft, a socket having a square hole to be fitted to the square rotary shaft, a shaft through hole penetrating the square rotary shaft in the radial direction, and a socket through hole penetrating the socket in the radial direction through the square hole A connecting pin that is inserted into the shaft through-hole and the socket through-hole and connects the socket and the rectangular rotary shaft, and an annular groove that is formed in the circumferential direction of the outer peripheral surface of the socket and passes over the socket through-hole. An impact rotary tool provided in the annular groove, and a cylindrical cover that is loosely fitted in the socket and covers the elastic ring of the annular groove; An intermediate member interposed between the cylindrical cover and the housing side in the direction of the axis of rotation of the shaft, the intermediate member covering the elastic ring, the rotational axis of the cylindrical cover The movement to the housing side in the direction is restricted.

According to the present invention, the cylindrical cover loosely fitted in the socket is restricted from moving toward the housing side in the direction of the rotation axis by the interposed member interposed between the cylindrical cover and the housing side. The cylindrical cover can always cover the elastic ring.
In addition, since the cylindrical cover is in a position that always covers the elastic ring, even if the elastic ring is removed from the socket, the cylindrical cover covers the annular groove, and there is no possibility that the connecting pin will immediately come out of the shaft through hole and socket through hole. Low.

  In the present invention, in the above-described impact rotary tool, a notch may be formed in the opening end of the cylindrical cover, and the notch may be set to a dimension that allows the connection pin to be inserted.

In this case, in order for the connecting pin to come out of the shaft through hole and the socket through hole, the cylindrical cover loosely fitted to the socket and the rectangular rotating shaft is moved to the housing side, the elastic ring is detached, and the notch And the position of the socket through hole in the circumferential direction must match each other.
Therefore, it is possible to further reduce the possibility that the connecting pin will come out of the socket through hole and the shaft through hole during use of the impact rotary tool.

  In the present invention, in the impact rotary tool, the interposed member may be an O-ring having elasticity.

  In this case, since an O-ring which is an off-the-shelf product is used as the interposed member, the cost and convenience are excellent.

  In the present invention, in the above-described impact rotary tool, an annular outer circumferential groove may be formed in the circumferential direction on the outer circumferential surface of the cylindrical cover.

In this case, when connecting the socket to the rectangular rotating shaft, an O-ring as an interposed member can be attached to the outer circumferential groove.
Thus, after the connecting pin is inserted and the elastic ring is mounted in the annular groove, the O-ring is loosely fitted to the rectangular rotating shaft when the O-ring is removed from the outer peripheral groove of the socket and moved to the housing side of the socket. Can do.
If the O-ring is attached to the outer peripheral groove, the O-ring does not interfere with the operation when the connecting pin is inserted, and the O-ring is easily moved to the rectangular rotation shaft.

  ADVANTAGE OF THE INVENTION According to this invention, the impact rotary tool which can maintain the state which the member which covers O-ring which prevents the connection pin from slipping out always covers O-ring can be provided.

It is a side view of the impact rotary tool which concerns on the 1st Embodiment of this invention. It is principal part sectional drawing which shows the connection state of the socket in an impact rotary tool. It is a disassembled perspective view of the principal part of an impact rotary tool. (A)-(d) It is principal part sectional drawing which shows the procedure of the connection of a socket. It is a disassembled perspective view of the principal part of the impact rotary tool which concerns on 2nd Embodiment. (A) is principal part sectional drawing of the impact rotary tool which concerns on 3rd Embodiment, (b) is the AA arrow directional view in (a).

(First embodiment)
Hereinafter, an impact wrench as an impact rotary tool according to the first embodiment will be described with reference to the drawings.
An impact wrench 10 shown in FIG. 1 includes a housing 11 that houses a drive unit 12.
The drive unit 12 of the impact wrench 10 of this embodiment is mainly composed of an electric motor.
The housing 11 has a hand gun type shape and includes a grip portion 13, and the grip portion 13 includes a switch 14 that supplies power to the drive portion 12.
As shown in FIG. 2, a shaft hole 15 is formed on the distal end side of the housing 11, and a rectangular rotating shaft 16 that is a part of the output shaft protrudes from the shaft hole 15 of the housing 11.

The square rotating shaft 16 is rotated by receiving a rotational driving force by the operation of the driving unit 12.
As shown in FIG. 3, the square rotation shaft 16 has a square cross-sectional shape that intersects the rotation axis P, and the side surface of the square rotation shaft 16 is formed by four planes 17.
As shown in FIGS. 2 and 3, the rectangular rotary shaft 16 is formed with a shaft through hole 18 that penetrates in the radial direction, and the shaft through hole 18 passes through the rotational axis P of the square rotary shaft 16.

A socket 20, which is a tightening tool, is connected to the rectangular rotating shaft 16 via a connecting pin 19.
A square hole 21 as a square hole to be fitted to the square rotation shaft 16 is formed at the base end portion of the socket 20 on the side connected to the square rotation shaft 16.
A hexagonal hole 22 having a hexagonal cross-sectional shape is formed at the distal end opposite to the base end of the socket 20, and the hexagonal hole 22 is a head of a hexagonal bolt (not shown) to be tightened. Or a hex nut (not shown).
The centers of the rectangular hole 21 and the hexagonal hole 22 formed in the socket 20 are coincident with each other, and in a state where the rectangular rotation shaft 16 is inserted into the square hole 21, the rotation axis P of the rectangular rotation shaft 16 is the socket 20. Coincides with the center of
A socket through hole 23 is formed in the socket 20 so as to penetrate in the radial direction.
The socket through-hole 23 is a through-hole formed so as to coincide with the center of the shaft through-hole 18 in a state where the rectangular rotary shaft 16 is fitted into the square hole 21, and allows the connection pin 19 to be inserted. .
Therefore, the socket through hole 23 communicates with the square hole 21 in the radial direction of the socket 20.

As shown in FIG. 3, the socket 20 includes an annular groove 24 that is formed over the circumferential direction of the outer peripheral surface and passes over the socket through hole 23.
The annular groove 24 is an annular groove that enables the mounting of an O-ring (hereinafter referred to as “first O-ring”) 25 as an elastic ring that prevents the connecting pin 19 from coming out of the socket through hole 23. is there.
The first O-ring 25 is a known O-ring formed of a rubber-based material having elasticity.
Since the inner diameter of the first O-ring 25 is set to be smaller than the diameter of the annular groove 24, in the state where the first O-ring 25 is attached to the annular groove 24, a force for tightening the socket 20 acts, The first O-ring 25 is in close contact with the socket 20.
The depth of the annular groove 24 is set to half the cross-sectional diameter of the first O-ring 25, and when the first O-ring 25 is mounted in the annular groove 24, the outer periphery of the first O-ring 25 is The side half protrudes from the annular groove 24.

In this embodiment, the socket 20 and the square rotary shaft 16 are connected by connecting the connecting pin 19 to the shaft through hole 18 and the socket through hole 23 in a state where the square rotary shaft 16 is inserted into the square hole 21 of the socket 20. Is done.
The impact wrench 10 includes a cylindrical cover 26 that covers the base end portion of the socket 20 in a state where the socket 20 and the square rotary shaft 16 are coupled.

In this embodiment, the cylindrical cover 26 is formed of the same metal material as the socket 20.
The cylindrical cover 26 includes a cylindrical peripheral wall portion 27 having an open end into which the base end portion of the socket 20 is inserted, and a perforated bottom portion 28 that comes into contact with the end surface of the base end portion of the socket 20 to be inserted. .
The peripheral wall portion 27 includes a first inner diameter surface 29 formed on the perforated bottom portion 28 side, and a second inner diameter surface 30 formed from the first inner diameter surface 29 toward the opening end.

The inner diameter of the first inner diameter surface 29 is set slightly larger than the outer diameter of the base end portion of the socket 20.
Therefore, the clearance between the first inner diameter surface 29 and the outer peripheral surface of the proximal end portion of the socket 20 that allows the socket 20 and the cylindrical cover 26 to be loosely fitted, that is, the socket 20 and the cylindrical cover 26 are relatively free to rotate. Clearance as much as possible is set.
The inner diameter of the second inner diameter surface 30 is set to be sufficiently larger than the inner diameter of the first inner diameter surface 29, and there is a gap G between the second inner diameter surface 30 and the outer peripheral surface of the proximal end portion of the socket 20. Is formed (see FIG. 2).
The gap G of this embodiment is set to a dimension (half the cross-sectional diameter of the first O-ring 25) corresponding to a portion protruding from the annular groove 24 in the first O-ring 25 mounted in the annular groove 24. ing.

As shown in FIG. 3, two cutouts 31 are formed at the opening end of the cylindrical cover 26 on the opposite side (the socket 20 side) from the perforated bottom portion 28.
These notches 31 are formed by being cut in a semicircular cross section from the open end of the cylindrical cover 26 toward the perforated bottom portion 28 side.
The notches 31 are provided at positions that are 180 degrees in the circumferential direction of the opening end of the cylindrical cover 26 with the rotation axis P as the center.
In this embodiment, the maximum diameter of the notch 31 is larger than the diameter of the connecting pin 19 and is the same as the diameters of the shaft through hole 18 and the socket through hole 23.
Therefore, the notch 31 allows the connecting pin 19 to be inserted.

An annular outer circumferential groove 32 formed in the circumferential direction is formed on the outer circumferential surface of the cylindrical cover 26.
The outer circumferential groove 32 is a groove that allows an O-ring (hereinafter referred to as “second O-ring”) 33 different from the first O-ring 25 to be mounted.
In this embodiment, the depth of the outer peripheral groove 32 is set to half of the cross-sectional diameter of the second O-ring 33, but the depth of the outer peripheral groove 32 is not half of the cross-sectional diameter of the second O-ring 33. For example, about 1/3 of the cross-sectional diameter of the second O-ring 33 may be used.
The outer circumferential groove 32 is a groove for temporarily depositing the second O-ring 33 on the outer circumferential surface of the cylindrical cover 26 without moving the second O-ring 33 in the direction of the rotation axis P.

The second O-ring 33 corresponds to an interposed member, and is an existing O-ring formed of a rubber-based material having elasticity.
In this embodiment, the inner diameter of the second O-ring 33 is set larger than the maximum diameter of the rectangular rotating shaft 16.
The sectional diameter of the second O-ring 33 is such that the socket 20 is connected to the rectangular rotary shaft 16, the first O-ring 25 is mounted in the annular groove 24, and the cylindrical cover 26 is connected to the first O-ring 25. In the covered state, the distance is smaller than the distance L formed between the housing 11 and the cylindrical cover 26.
The cross-sectional diameter of the second O-ring 33 is set to be not less than half the cross-sectional diameter of the first O-ring 25.

A circular hole 34 is formed at the center of the perforated bottom portion 28 of the cylindrical cover 26, and the circular hole 34 allows the rectangular rotary shaft 16 to be inserted.
Therefore, the hole diameter of the circular hole 34 is set to be larger than the maximum diameter of the rectangular rotating shaft 16.
The hole diameter of the circular hole 34 is set to be smaller than the diameter of the base end portion of the socket 20, and the base end portion of the socket 20 does not contact the perforated bottom portion 28 and does not penetrate the cylindrical cover 26.

  When the socket 20 is connected to the rectangular rotary shaft 16 and the first O-ring 25 is mounted in the annular groove 24, the cylindrical cover 26 configured as described above has the first O-ring as shown in FIG. Cover the ring 25.

Next, a procedure for connecting the socket 20 to the rectangular rotating shaft 16 of the impact wrench 10 will be described.
As shown in FIG. 4A, the state before the socket 20 is connected to the rectangular rotating shaft 16 is the connection pin 19, the socket 20, the first O-ring 25, the second O-ring 33, and the cylindrical cover 26. Exist individually.
First, the first O-ring 25 is temporarily attached to the outer peripheral surface on the tip side of the annular groove 24 of the socket 20 in advance, and the second O-ring 33 is attached to the outer peripheral groove 32 of the cylindrical cover 26 in advance. deep.

Next, after the rectangular rotating shaft 16 is inserted into the circular hole 34 of the cylindrical cover 26, the rectangular rotating shaft 16 is inserted into the rectangular hole 21 of the socket 20.
When the rectangular rotating shaft 16 is fitted into the square hole 21, the rotation direction of the socket 20 and the rectangular rotating shaft 16 is aligned with the position of the rotation axis P so that the shaft through hole 18 and the socket through hole 23 communicate with each other.
Next, the cylindrical cover 26 is moved to the housing 11 side in the direction of the rotation axis P and rotated to align the notch 31 of the cylindrical cover 26 with the socket through hole 23 in the circumferential direction.
As shown in FIG. 4B, the connecting pin 19 is connected to the socket through hole 23 and the shaft through hole through the notch 31 in a state where the notches 31 of the cylindrical cover 26 and the circumferential positions of the socket through holes 23 match. 18 is inserted.

The first O, which is temporarily mounted on the outer peripheral surface of the socket 20 on the tip side of the annular groove 24, while maintaining the state where the inserted connecting pin 19 does not come out of the socket through hole 23 and the shaft through hole 18. The ring 25 is moved to the housing 11 side. Then, as shown in FIG. 4C, the first O-ring 25 is attached to the annular groove 24.
Further, the cylindrical cover 26 is rotated with respect to the socket 20 so that the positions of the notch 31 and the socket through hole 23 of the cylindrical cover 26 are inconsistent.
Both ends of the connecting pin 19 in this state are covered with the first O-ring 25, and the connecting pin 19 does not come out of the socket through hole 23 and the shaft through hole 18.

Next, the cylindrical cover 26 is moved in the direction away from the housing 11 in the direction of the rotation axis P.
When the perforated bottom portion 28 of the cylindrical cover 26 contacts the end surface of the base end portion of the socket 20, the cylindrical cover 26 is positioned farthest from the housing 11.
In this state, a gap of a distance L is formed between the cylindrical cover 26 and the housing 11.
While maintaining this state, the second O-ring 33 attached to the outer circumferential groove 32 is pulled out from the outer circumferential groove 32 toward the housing 11 side, and as shown in FIG. The second O-ring 33 is dropped into the gap of the distance L between the first and second members 11.

The second O-ring 33 is interposed between the cylindrical cover 26 and the housing 11 in a loosely-fitted state on the rectangular rotary shaft 16 in the gap, and even if the cylindrical cover 26 tries to move toward the housing 11, The O-ring 33 restricts the movement of the cylindrical cover 26.
Since the second O-ring 33 restricts the movement of the cylindrical cover 26 toward the housing 11, the cylindrical cover 26 covers the first O-ring 25 mounted in the annular groove 24.

Although the first O-ring 25 and the cylindrical cover 26 are in contact with each other, the cylindrical cover 26 is in a loosely fitted state with respect to the socket 20, and the cylindrical cover 26 and the first O-ring 33 are The frictional force due to contact is small.
For this reason, when the impact wrench 10 is operated and the operator puts his / her hand on the cylindrical cover 26, the socket 20 and the rectangular rotary shaft 16 rotate with respect to the cylindrical cover 26.
When the hand is not attached to the cylindrical cover 26, the cylindrical cover 26 rotates together with the socket 20 and the rectangular rotating shaft 16.
Therefore, even if the operator works with the left hand, the hand does not directly hit the O-ring 33, and the O-ring 33 does not come off from the through hole 23. Therefore, the connecting pin 19 does not fall off.

Due to the long-term use of the impact wrench 10 and the like, for example, the connection pin 19 does not fall off immediately when the second O-ring 33 is cut and dropped from the impact wrench 10.
In order for the connecting pin 19 to fall out of the socket through-hole 23, the cylindrical cover 26 moves to the housing 11 side in the direction of the rotation axis P, and the first O-ring 25 comes off the annular groove 24. It is necessary to satisfy the condition that the positions of the notch 31 and the socket through hole 23 coincide.

Further, even when the first O-ring 25 first drops, the connecting pin 19 does not drop immediately.
In this case, unless the three conditions of dropping off the second O-ring 33 from the rectangular rotary shaft 16, moving the cylindrical cover 26 toward the housing 11, and matching the positions of the notch 31 and the socket through hole 23 are satisfied. There is no possibility that the connecting pin 19 will fall out of the socket through hole 23.

When the connection between the socket 20 and the rectangular rotating shaft 16 is released, the procedure reverse to the procedure for connecting the socket 20 to the rectangular rotating shaft 16 shown in FIGS. 4 (a) to 4 (d) is performed. Good.
First, the second O-ring 33 is attached to the outer peripheral groove 32 of the cylindrical cover 26 from the gap, and the cylindrical cover is moved.
Thereafter, the first O-ring 25 is removed from the annular groove 24, and the notch 31 of the cylindrical cover 26 and the circumferential position of the socket through hole 23 are aligned.
Since the positions of the notch 31 and the socket through-hole 23 coincide with each other in the circumferential direction, the connecting pin 19 can be extracted, and the connection between the socket 20 and the rectangular rotating shaft 16 can be released.

The above embodiment has the following effects.
(1) Since the cylindrical cover 26 loosely fitted in the socket 20 is restricted from moving toward the housing 11 by the second O-ring 33 interposed between the cylindrical cover 26 and the housing 11 side. The cylindrical cover 26 can always cover the first O-ring 25. Further, since the cylindrical cover 26 is present at a position that always covers the first O-ring 25, the cylindrical cover 26 covers the annular groove 24 even when the first O-ring 25 is detached from the socket 20, and the connecting pin 19 is The shaft through hole 18 and the socket through hole 23 do not come out immediately. In this case, in order for the connecting pin 19 to come out of the socket through-hole 23, the cylindrical cover 26 loosely fitted in the socket 20 is moved to the housing 11 side, the first O-ring 25 is removed, and further the cutting is performed. It is necessary for the notch 31 and the socket through hole 23 to coincide. Therefore, it is possible to further reduce the possibility that the connecting pin 19 is pulled out during use of the impact wrench 10.

(2) Since the second O-ring 33 having elasticity is used, an O-ring that is an off-the-shelf product can be used, and it is excellent in cost and convenience, and the second O-ring 33 is used to form a square shape. It is easy to loosely fit the second O-ring 33 to the rotating shaft 16.

(3) Since the cylindrical cover 26 has an annular outer circumferential groove 32 formed over the circumferential direction of the outer circumferential surface, the second O-ring 33 is connected when the socket 20 is connected to the rectangular rotating shaft 16. Can be mounted in the outer circumferential groove 32. After the connecting pin 19 is inserted into the socket through hole 23 and the shaft through hole 18, the first O ring 25 is attached to the annular groove 24, and then the second O ring 33 is removed from the outer peripheral groove 32 and the cylindrical cover 26. The second O-ring 33 is loosely fitted to the rectangular rotating shaft 16. If the second O-ring 33 is attached to the outer peripheral groove 32, the second O-ring 33 does not interfere with the operation when the connecting pin 19 is inserted, and the second O-ring 33 is square. Easy to move to the rotating shaft 16.

(Second Embodiment)
Next, an impact rotary tool according to the second embodiment will be described.
The impact rotary tool of the second embodiment is an impact wrench as in the first embodiment, but is an example in which the shape of the cylindrical cover is different from that of the first embodiment.
In 2nd Embodiment, about the element which is common in 1st Embodiment, the description of 1st Embodiment is used and a code | symbol is also used in common.

A cylindrical cover 41 shown in FIG. 5 includes a peripheral wall portion 42 and a perforated bottom portion 43.
The peripheral wall portion 42 includes a first inner diameter surface 44 formed on the perforated bottom portion 43 side, and a second inner diameter surface 45 formed on the opposite side of the perforated bottom portion 43 side from the first inner diameter surface 44.
The first inner diameter surface 44 is set to an inner diameter slightly larger than the outer peripheral diameter of the base end portion of the socket 20, and the socket 20 and the cylindrical cover 41 are loosely fitted.
The inner diameter of the second inner diameter surface 45 is set to be larger than the inner diameter of the first inner diameter surface 44.

As shown in FIG. 5, a notch 46 is formed at the opening end of the cylindrical cover 41 that is opposite to the perforated bottom portion 43 (socket side).
The notch 46 is formed by cutting toward the perforated bottom 43 in the range of about a half circumference at the open end of the cylindrical cover 41.
The cut amount of the notch 31 toward the perforated bottom 43 is larger than the diameter of the connecting pin 19 and is the same as the diameters of the shaft through hole 18 and the socket through hole 23.
An annular outer circumferential groove 47 formed in the circumferential direction of the outer circumferential surface is formed on the outer circumferential surface of the cylindrical cover 41, and the outer circumferential groove 47 allows the second O-ring 33 to be attached.

A circular hole 48 is formed in the center of the perforated bottom portion 43 of the cylindrical cover 41, and the circular hole 48 allows the rectangular rotary shaft 16 to be inserted.
The diameter of the circular hole 48 is set to be larger than the maximum diameter of the rectangular rotary shaft 16 and is set to be smaller than the diameter of the proximal end portion of the socket 20. The base end portion of the socket 20 does not contact the perforated bottom portion 43 and does not penetrate the cylindrical cover 41.

According to the second embodiment, in a state where the rectangular rotary shaft 16 and the socket 20 are connected, the cylindrical cover 41 always covers the first O-ring 25 attached to the socket 20, and the first As in the embodiment, the connecting pin 19 can be prevented from coming off.
In the case of connecting or releasing the rectangular rotary shaft 16 and the socket 20, the cylindrical cover 41 may be moved to the housing 11 side and the socket through hole 23 may be exposed to the notch 46. As a result, the connecting pin 19 can be inserted into or extracted from the socket through hole 23 and the shaft through hole 18.

(Third embodiment)
Next, an impact rotary tool according to a third embodiment will be described.
The impact rotary tool of the third embodiment is an impact wrench as in the first embodiment.
The impact wrench according to the third embodiment is different from the first embodiment in that a C-ring is used instead of an O-ring as an interposed member.
In 3rd Embodiment, about the element which is common in 1st Embodiment, the description of 1st Embodiment is used and a code | symbol is also used in common.

A C-ring as an interposing member of an impact rotary tool according to the third embodiment is shown in FIGS. 6 (a) and 6 (b).
As shown in FIG. 6A, the C ring 51 is loosely fitted to the rectangular rotating shaft 16 between the cylindrical cover 26 and the housing 11.
As shown in FIG. 6B, the C-ring 51 is formed in a C shape from a metal material.
The C-ring 51 can be elastically deformed, and can be fitted to the rectangular rotating shaft 16 from the side of the rectangular rotating shaft 16 by enlarging the space between both ends 52 and 52 of the C-ring 51.

According to this embodiment, the C-ring 51 can function as an intervening member like the second O-ring 33.
Further, when the C ring 51 is used, it is not necessary to temporarily attach the outer peripheral groove 32 of the cylindrical cover 26 as in the case of the second O ring 33, and after the rectangular rotary shaft 16 and the socket 20 are connected. Also, the C-ring 51 can be fitted to the rectangular rotating shaft 16.

The impact rotary tool according to each of the above embodiments represents an embodiment of the present invention, and the present invention is not limited to each of the above embodiments, and the gist of the invention is as follows. Various changes can be made within the range.
In the above embodiment, the impact wrench includes an electric motor as a drive unit. However, the drive unit may be an air motor driven by compressed air, for example. In the above embodiment, the impact wrench has been described as an example of the impact rotary tool. However, the impact rotary tool may be an impact driver in addition to the impact wrench. In this case, the socket tip side is replaced with a hexagon hole. It becomes.
In the above embodiment, when the socket is connected to the rectangular rotation shaft, the second O-ring is temporarily mounted in the outer circumferential groove formed in the cylindrical cover, and the second O-ring is oriented in the direction of the rotation axis. Although the movement is restricted, it is not limited to mounting the second O-ring in the outer circumferential groove. For example, a rib or a step formed in the circumferential direction of the outer peripheral surface of the cylindrical cover is provided, and the movement of the second O-ring in the rotational axis direction on the outer peripheral surface of the cylindrical cover is regulated by the rib or the step. It may be.
In the above embodiment, the interposition member is interposed between the housing and the cylindrical cover, and the interposition member is in sliding contact with the housing and the cylindrical cover, but is not limited thereto. For example, a step portion may be provided by forming a shaft portion having a larger diameter than the rectangular rotation shaft on the housing side of the rectangular rotation shaft, and an interposition member may be interposed between the cylindrical cover and the shaft portion. The interposition member is in sliding contact with the cylindrical cover and the stepped portion.
In the above embodiment, the O-ring is used as the elastic ring, but a ring having elasticity other than the O-ring may be used, for example, a square ring or a D-ring may be used.

DESCRIPTION OF SYMBOLS 10 Impact wrench 11 Housing 12 Drive part 16 Rectangular rotating shaft 18 Shaft through-hole 19 Connecting pin 20 Socket 21 Square hole 23 Socket through-hole 24 Annular groove 25 1st O-ring (as an elastic ring)
26, 41 Cylindrical covers 29, 44 First inner diameter surface 30, 45 Second inner diameter surface 31, 46 Notch 32, 47 Outer peripheral groove 33 Second O-ring (as intervening member)
51 C-ring (as an intervening member)
G Gap L Distance P Center of rotation

Claims (4)

A housing that houses the drive,
A rectangular rotary shaft that protrudes from the housing and is rotated by the operation of the drive unit and has a square cross-sectional shape across the rotation axis,
A socket having a square hole to be fitted to the square rotation shaft;
A shaft through hole penetrating the square rotation shaft in a radial direction;
A socket through hole penetrating the socket in the radial direction through the square hole;
A connecting pin that is inserted into the shaft through hole and the socket through hole, and connects the socket and the rectangular rotating shaft;
An annular groove formed in the circumferential direction of the outer peripheral surface of the socket and passing over the socket through hole;
An impact rotary tool comprising an elastic ring mounted in the annular groove,
A cylindrical cover that is loosely fitted into the socket and covers the elastic ring of the annular groove;
An interposition member interposed between the cylindrical cover and the housing side in the rotational axis direction of the rectangular rotary shaft,
The impact rotary tool characterized in that the interposition member restricts movement of the cylindrical cover in a state of covering the elastic ring toward the housing in the direction of the rotation axis.   2. The impact rotary tool according to claim 1, wherein a cutout is formed at an opening end of the cylindrical cover, and the cutout is set to a dimension that allows the connection pin to be inserted.   The impact rotary tool according to claim 1, wherein the interposed member is an O-ring having elasticity.   The impact rotary tool according to any one of claims 1 to 3, wherein an annular outer circumferential groove is formed in a circumferential direction on the outer circumferential surface of the cylindrical cover.

Images