JP4170871B2 - Tool retainer for impact tools - Google Patents

Description

  The present invention relates to a tool retainer for an impact tool that is provided at the tip of an impact tool such as a hammer drill and holds the tool.

  The tool retainer for impact tool (hereinafter referred to as “tool retainer”) is fixed to the front end of a housing such as a hammer drill as disclosed in, for example, Patent Document 1 below, and a cylindrical tool holder into which a tool is inserted, The base end of the U-shaped retainer is pivotally attached to the shaft. That is, the tool is prevented from coming off by fitting a notch provided in the center of the front end of the retainer to the small diameter portion of the loosely inserted tool and locking the rotation of the retainer. In particular, Patent Document 1 discloses a structure in which the retainer is locked by fitting a push button that is protruded and biased behind the retainer shaft-attaching portion of the tool holder and a notch formed at the proximal end of the retainer. Is described.

Japanese Utility Model Publication No. 61-71381 Japanese Utility Model Publication No. 2-3380 Japanese Utility Model Publication No. 2-19485

  In this case, in order to unlock the retainer when removing the tool, the push button is pushed in to avoid interference with the base end of the retainer. At this time, the base end of the rotating retainer is pushed. There is a risk of hitting a finger pushing the button, and the operability is lowered. Therefore, Patent Document 2 and Patent Document 3 disclose a device in which a protrusion for pushing operation is provided on the distal end side of the push button to prevent interference between the proximal end of the retainer and the finger. However, in this case, when the push button is not pushed in, the tip of the push button always protrudes from the tool holder, so that it interferes with the operation of the electric tool itself or the side handle or the like. .

  Accordingly, the inventions of claims 1, 3, and 4 can perform the rotation lock and release of the retainer when the tool is attached / detached with good operability, and the operability of the electric tool itself with fewer protruding portions. The purpose of this is to provide a tool retainer that does not affect the above.

In order to achieve the above object, according to a first aspect of the present invention, a ring member is rotatably mounted on the rear side of the retainer shaft attachment portion in the tool holder, and the ring member is mounted at the tool holding position. A lock portion that can prevent the retainer from rotating is provided in contact with or close to the base end of the retainer, and the lock portion is moved by rotating the ring member, so that the retainer can be rotated at the tool holding position. The lock and the release thereof can be selected.
According to the second aspect of the present invention, in addition to the object of the first aspect, the lock portion locks the rotation of the retainer to the ring member in order to eliminate the risk of erroneous operation of the ring member and increase the reliability of tool holding. An urging means for urging and rotating so as to be in the position to be operated is provided.

To achieve the above object, according to a second aspect of the present invention, a lock button along a side surface of the tool holder is provided by a pin in a tangential direction of the tool holder behind the retainer shaft attachment portion in the tool holder . The front and rear ends of the lock button are pivotably mounted, and a biasing means for pressing the front end of the lock button against the base end of the retainer is provided, while the front end of the lock button can be fitted to the base end of the retainer at the tool holding position. By forming a cut-out part and pushing the rear end of the lock button or releasing it, the front end is fitted to and detached from the cut-out part of the retainer to lock and release the rotation of the retainer at the tool holding position. It is characterized by being selectable.

In order to achieve the above object, a third invention according to claim 4 is characterized in that a lock button that is urged outwardly by the urging means is projected and retracted behind the retainer shaft attachment portion in the tool holder. while possible providing, on the base end rear side of the retainer, the front portion of the lock button in the tool holding position to form a fitting recess capable of, a rotation locus of the proximal end of the retainer at the rear side of the front portion of the lock button Form a rear part that is higher than the front part at a position where it does not interfere and the front part fits into the recess at a height equal to or lower than the outer surface of the retainer, and push the lock button using the rear part or the releasing operation, by Hamada' the front portion against the concave portion of the retainer, is characterized in that the locking of the retainer of the rotation of the tool holding position and its release and the selectable.
According to the fifth aspect of the present invention, in addition to the object of the fourth aspect, in order to increase the reliability of the lock by the lock button, the lock fitted into the recess of the retainer between the tool holder and the lock button is provided. A restricting means for restricting the protruding position of the lock button is provided so that the lock button and the retainer are not in contact with each other at the protruding position of the button.

According to the first and third aspects of the present invention, the retainer can be locked and released when the tool is attached and detached with good operability. Further, since the ring member and the lock button are provided without protruding outward from the retainer, there is no possibility that the operation of the hammer drill itself will be disturbed.
According to the second aspect of the invention, in addition to the effect of the first aspect, the retainer lock is maintained in a normal state to reduce the possibility of erroneous operation, and the reliability of tool holding is increased.
According to the fifth aspect of the present invention, in addition to the effect of the fourth aspect, accidental release of the lock button or rotation of the retainer due to impact is prevented, and the reliability of the retainer lock by the lock button is higher. Become.

<< Form 1 >>
First, an embodiment corresponding to the first invention will be described. FIG. 1 is an overall view of a hammer drill. A housing 2 of the hammer drill 1 includes a motor (not shown) and a striking mechanism for converting the rotation of the motor into the forward and backward movement of a piston. A cylindrical barrel 3 is connected to the front of the housing 2 (left side in FIG. 1), and a striker 5 that moves forward and backward in conjunction with the piston is inserted into a cylinder 4 that is pivotally supported in the barrel 3. Has been. Reference numeral 6 denotes a handle that extends rearward of the housing 2, and 7 denotes a side handle that is mounted orthogonally to the barrel 3.
8 is a tool retainer mounted in front of the barrel 3. The tool retainer 8 includes a cylindrical tool holder 9 fixed coaxially with the barrel 3, and a pair of upper and lower pins 11 on the front side of the tool holder 9. 11, and a U-shaped retainer 10 that is pivotally mounted by the motor 11. The retainer 10 is pivotable between a tool holding position protruding forward along the axis of the tool holder 9 and a holding release position tilting a predetermined angle therefrom, and is drilled in the axis of the tool holder 9. The impact bolt 13 is accommodated so as to be movable back and forth across the through hole 12 and the cylinder 4 formed.

  In the tool retainer 8, pins 11, 11 that pivotally mount the retainer 10 are press-fitted into the tool holder 9, and a stopper for retaining the screw that is screwed into the tool holder 9 as shown in FIG. Screws 14 and 14 are locked. Further, rubber sleeves 15 are respectively sheathed in the penetrating portions of the retainer 10 in the pins 11. The sleeve 15 is for reducing an impact transmitted from the retainer 10 to the tool holder 9 or the barrel 3 side when the hammer drill 1 is used. One pin 11 is provided with a through hole 16 penetrating the shaft center, and this through hole 16 is used for inserting a rod or the like and pushing it out from the inside when the other pin 11 is removed. It is.

  Further, in the tool holder 9, a lock ring 17 as a ring member is externally provided on the rear side of the axially attached portion of the retainer 10. The lock ring 17 has an outer diameter substantially the same as the outer dimension between the proximal ends of the retainer 10, and extends in the circumferential direction in a concave groove 18 formed in the circumferential direction toward the inner circumference as shown in FIGS. A spring receiver 19 in which support pins 20 and 20 are arranged side by side is accommodated, and one ends of coil springs 21 and 21 are externally mounted on the support pins 20 and 20, respectively. On the other hand, on the outer periphery of the tool holder 9 in the concave groove 18, a spring receiver 22 in which support pins 23, 23 are arranged side by side in the circumferential direction on the circumferential extension of the support pins 20, 20 is fixed by a pin 9 a. The other ends of the coil springs 21 and 21 are covered with support pins 23 and 23, respectively. Therefore, the lock ring 17 is normally urged to rotate to the position shown in FIG. 3A where the spring receivers 19 and 22 are pressed against both ends of the groove 18 by the elasticity of the two coil springs 21 and 21. Is rotated in the direction indicated by the arrow in the figure against the bias of the coil springs 21 and 21, the support pins 20 and 23 can be rotated to the position shown in FIG.

  Then, as shown in FIG. 5, a pair of notches 24 and 24 are formed at a point-symmetrical position at the front end of the lock ring 17. 3A of the lock ring 17 is separated in the circumferential direction from the inclined corner 10a at the proximal end of the retainer 10 at the tool holding position as shown in FIG. 5A. It is set to be a position. Therefore, in this state, the front end edge 17a serving as the lock portion of the lock ring 17 contacts the base end of the retainer 10 to prevent the retainer 10 from rotating (lock position). 3B of the lock ring 17, the notch 24 is located behind the corner 10a of the retainer 10 as shown in FIG. 5B, and the retainer 10 is placed as shown in FIG. Allow tilting (unlocked position). A second concave groove 25 for holding the leaf spring 26 is formed on the inner peripheral surface of the lock ring 17, and the central projecting portion 27 of the leaf spring 26 is shown in FIGS. 3 (A) and 5 (A). Is engaged with a recess 28 formed on the outer periphery of the tool holder 9 to obtain the click action of the lock ring 17 at the lock position.

  In the tool retainer 8 configured as described above, when the tool is mounted, when the lock ring 17 is rotated to the unlocking position in FIG. 3B, the front edge 17a is retracted from the rear of the retainer 10 as described above. Instead, the notches 24 and 24 are positioned to allow the retainer 10 to tilt. Therefore, if the retainer 10 is rotated to the rear holding release position as shown in FIG. 5C to open the front of the tool holder 9, the tool 29 can be inserted into the through hole 12. After the tool 29 is inserted, the retainer 10 is rotated again to the front tool holding position, and the lock ring 17 is returned to the lock position shown in FIG. This prevents the retainer 10 from rotating. In this state, the notch 31 formed in the center of the retainer 10 is fitted into the small diameter portion 30 of the tool 29, and the tool 29 is prevented from coming off forward. These procedures are the same when the tool 29 is removed.

As described above, according to the above-described embodiment, the lock ring 17 is rotatably mounted on the rear side of the retainer 10 in the tool holder 9 so as to be rotatable, and the base end of the retainer 10 at the tool holding position is provided on the lock ring 17. Is provided with a front edge 17a that can prevent the retainer 10 from rotating and the lock ring 17 is rotated to move the front edge 17a and lock the rotation of the retainer 10 at the tool holding position. Since the release can be selected, the rotation lock of the retainer 10 accompanying the attachment / detachment of the tool 29 and the release thereof can be performed with good operability. Further, since the lock ring 17 is provided without protruding outward from the retainer 10, there is no possibility that the operation of the hammer drill itself will be disturbed.
In particular, the lock ring 17 is provided with coil springs 21 and 21 that urge the rotation so that the front end edge 17a is positioned to lock the rotation of the retainer 10, so that the lock of the retainer 10 is maintained in a normal state and an erroneous operation occurs. The risk is reduced and the tool holding reliability is increased.

The coil spring that rotationally biases the lock ring 17 may be a single stage, or other biasing means such as a torsion spring or a leaf spring may be used in addition to the coil spring. However, these urging means may be eliminated and the lock ring may be arbitrarily rotated between the locked position and the unlocked position. In this case, a leaf spring or the like is used at each of the locked position and the unlocked position. It is desirable to get a click.
Further, the front edge 17a of the lock ring 17 does not necessarily have to be brought into contact with the proximal end of the retainer 10 at the locked position. If the rotation of the retainer 10 can be prevented by interfering with the corner portion 10a, the front end edge 17a remains at the rear adjacent position. May be.

  On the other hand, in the above embodiment, the front end edge 17a of the lock ring 17 is formed long in the circumferential direction and the notch 24 is partially provided. On the contrary, the notch is formed long in the circumferential direction, and the retainer The front end edge (convex portion) that is close to or in contact with the base end of 10 is partially left, and the convex portion is retracted from the rear of the retainer by the rotation of the lock ring to allow the retainer to rotate. You can also. In this case as well, a biasing means to the lock position where the convex portion is located behind the retainer may or may not be provided.

<< Form 2 >>
Next, an embodiment corresponding to the second invention will be described. In addition, the structure code | symbol which overlaps with the structure 1 of a hammer drill etc. attaches | subjects the same code | symbol, and abbreviate | omits description.
As shown in FIGS. 6 and 7, lock buttons 32 and 32 are provided on the tool holder 9 in place of the lock ring. This lock button 32 is in a pair of left and right recesses 37, 37 provided in the tool holder 9 at the rear of the base end of the retainer 10, and has a square plate-like operation portion 33 having a front end bulged in a circular shape, It is formed of a pair of support portions 34 and 34 projecting from both sides of the operation portion 33 toward the tool holder 9, and can be swung by a pin 35 that pivotally supports the support portions 34 and 34. Further, a torsion spring 36 is externally mounted on the pin 35, and the front end is urged to rotate in a direction in which the tool holder 9 is pressed.

  Further, here, the rear portion of the pin 11 on the proximal end side of the retainer 10 is in a position where it interferes with the front end of the lock button 32 that is rotationally biased, and the circular portion of the front end of the lock button 32 is formed on the surface thereof. Removable portions 38 that can be fitted are formed. Therefore, when the front ends of the lock buttons 32 and 32 are fitted into the cut portions 38 and 38 at the tool holding position of the retainer 10 as shown by solid lines in FIGS. It is maintained in the posture along. When the rear ends of the lock buttons 32 and 32 are pushed in from here and rotated against the urging force of the torsion spring 36, the front ends are lifted as shown by the two-dot chain lines in FIG. To do. In this separated state, the movement trajectory on the proximal end side accompanying the rotation of the retainer 10 does not interfere with the front ends of the lock buttons 32 and 32.

  In the tool retainer 8 configured as described above, when the tool 29 is mounted, when the rear ends of the lock buttons 32 and 32 are pushed in as described above, the front ends of the lock buttons 32 and 32 become the cut portions 38 and 32 of the retainer 10. Since the retainer 10 is allowed to tilt, the retainer 10 is tilted as shown by a two-dot chain line in FIG. 7A and the tool 29 is inserted into the through hole 12 of the tool holder 9. Thereafter, when the retainer 10 is returned to the front side and the push-in of the lock buttons 32, 32 is released, the front ends of the lock buttons 32, 32 are fitted again into the cut portions 38, 38, and the rotation of the retainer 10 is locked.

  As described above, also in the second embodiment, the lock button 32 along the side surface of the tool holder 9 is pivotally attached to the tool holder 9 so that the front and rear ends can swing, and the front end of the lock button 32 is used as the base end of the retainer 10. While providing the torsion spring 36 to be pressed, the base end of the retainer 10 is formed with a cutout portion 38 into which the front end of the lock button 32 can be fitted at the tool holding position, and the rear end of the lock button 32 is pushed in or released. Thus, the retainer 10 accompanying the attachment / detachment of the tool 29 can be selected by fitting the front end to the cutting portion 38 of the retainer 10 and selecting the lock and release of the rotation of the retainer 10 at the tool holding position. Can be rotated and released with good operability. In addition, the lock buttons 32 and 32 hardly protrude outward when fitted to the cut portion 38, so that there is no possibility that the operation of the hammer drill itself will be disturbed.

<< Form 3 >>
An embodiment corresponding to the third invention will be described. In addition, the description of the components that overlap with the configuration 1 such as the configuration of the hammer drill is omitted as in the configuration 2.
As shown in FIGS. 8 and 9, the lock button 39 provided on the tool holder 9 has a planar circular shape, and the inside of the accommodating portion 40 having the same shape recessed at one base end of the retainer 10 in the tool holder 9. The coil spring 41 is urged in an outward projecting direction by a coil spring 41 serving as an urging means provided between the housing 40 and the bottom surface of the housing 40. Here, a semicircular recess 44 into which the front portion 42 of the lock button 39 can be fitted is formed on the rear surface of the proximal end of the retainer 10, and the lock is applied in the fitted state of the front portion 42 that is projected and biased. It is possible to restrict the protruding position of the button 39 and to lock the rotation of the retainer 10.

Further, the rear portion 43 serving as the pressing portion of the lock button 39 has a curved shape in which the front end edge does not interfere with the rotation trajectory of the proximal end of the retainer 10 and is higher than the front portion 42, and at the protruding position of the lock button 39. It is formed at a height that is less than or equal to the outer surface of the retainer 10. Further, the stroke that is sunk by pressing the lock button 39 is set to be larger than the depth of the recess 44 of the retainer 10 to which the front portion 42 is fitted.
On the other hand, the tool holder 9 is fitted with a pin 45 projecting in the radial direction into the accommodating portion 40 and engaged with a notch 46 also formed in the radial direction on the bottom side of the lock button 39. That is, the lock button 39 is prevented from rotating so that the lock button 39 can always appear and appear at an appropriate position.

  In the tool retainer 8 configured as described above, when the tool 29 is mounted, when the tool retainer 8 is pushed into the accommodating portion 40 using the rear portion 43 of the lock button 39, as shown in the enlarged view of the portion A in FIG. The front portion 42 of the lock button 39 is separated downward from the concave portion 44 of the retainer 10 to allow the retainer 10 to be tilted. Therefore, the retainer 10 is tilted as shown by a two-dot chain line in FIG. A tool 29 is inserted into the nine through holes 12. Thereafter, when the retainer 10 is returned to the front side and then the push of the lock button 39 is released, the front portion 42 of the lock button 39 is fitted again into the recess 44 and the rotation of the retainer 10 is locked.

  As described above, also in the third embodiment, the tool holder 9 is provided with the lock button 39 urged in the outward projecting direction by the coil spring 41 so that the lock button 39 can be projected and retracted. A recess 44 into which the front portion 42 of the lock button 39 can be fitted is formed. When the lock button 39 is pressed using the pressing portion 43 or released, the front portion 42 is fitted to and detached from the concave portion 44 to lock the rotation of the retainer 10 at the tool holding position. And the release thereof can be selected, the rotation lock of the retainer 10 accompanying the attachment / detachment of the tool 29 and the release thereof can be performed with good operability. Moreover, since the rear part 43 of the lock button 39 does not always protrude outward from the retainer 10, there is no possibility that the operation of the hammer drill itself will be disturbed.

  In the second embodiment, the lock buttons 32 are provided on both the left and right sides of the tool holder 9. However, the configuration may be simplified by providing the lock buttons 32 on only one of them as in the third embodiment. On the contrary, in the third mode, the lock button 39 is provided on only one side. However, as in the second mode, the tool retainer 10 may be securely locked by being provided on both the left and right sides.

  In particular, in the third aspect, the retainer 10 directly contacts the lock button 39 to prevent the lock button 39 from being removed. In this case, if the hammer drill has a large idle energy, The retainer 10 rattles due to a gap between the holder 9 and the pin 11, and the rattling is transmitted to the lock button 39, and the lock button 39 that can move only in the direction of the housing portion 40 is detached from the housing portion 40. There is a risk that the tool 29 may come off. Therefore, as shown in FIGS. 10 and 11, the tool holder 9 is provided with a stopper pin 47 protruding forward in the housing portion 40, while the stopper pin 47 is loosely inserted on the front surface of the lock button 39, and the lock button 39 is pushed in. A locking groove 48 that ends in the axial direction is provided in the axial direction, and the lock button 39 urged in the protruding direction is locked to the stopper pin 47 to restrict the protruding position. It is desirable to set so that it is close to the retainer 10 and is not contacted in the protruding direction.

In this way, by providing the restricting means including the stopper pin 47 and the locking groove 48, the impact due to idle driving is not transmitted to the lock button 39. Therefore, accidental detachment of the lock button 39 or tilting of the retainer 10 due to an impact is prevented, and the reliability of the lock of the retainer 10 by the lock button 39 is increased.
The restricting means is not limited to the structure of the stopper pin 47 and the locking groove 48, and conversely, the locking groove provided on the inner wall side of the housing portion 40 and the protrusion provided on the lock button 39. It can also be set as the structure by latching.

It is a general view of the hammer drill of form 1. (A) is a cross-sectional view of the axially attached portion of the retainer in the tool retainer, and (B) is a cross-sectional view along the line AA. (A) is a cross-sectional view of the lock ring portion, and (B) is a cross-sectional view of the lock ring portion. (A) is a BB line sectional view, (B) is a partial sectional view of a lock ring. (A) is a side view of the tool retainer at the lock ring lock position, (B) is a side view of the tool retainer at the lock ring unlock position, and (C) is a tool retainer in which the retainer is tilted to the holding release position. FIG. (A) is a longitudinal cross-sectional view of the tool retainer in form 2, (B) is an A section enlarged view. (A) is a side view of a tool retainer, (B) is a cross-sectional view of a lock button portion. It is a longitudinal cross-sectional view of the tool retainer in form 3. (A) is a side view of a tool retainer, (B) is a cross-sectional view of a lock button portion. It is a partial longitudinal cross-sectional view of the hammer drill which shows the example of a change of form 3. (A) (B) is an expanded sectional view of a lock button part, respectively ((A) is a lock button pushing state, (B) is a pushing release state), (C) is a B arrow view.

Explanation of symbols

1. Hammer drill, 2. Housing, 3. Barrel, 8. Tool retainer, 9. Tool holder, 10. Retainer, 11. Pin, 17. Lock ring, 17a, Front edge, 21 .. Coil spring, 29 .. Tool, 32, 39 .. Lock button, 33 .. Operation part, 34 .. Support part, 37 .. Recessed part, 38 .. Cutting part, 40. Front part, 43 .. Back part, 47 .. Stopper pin, 48 .. Locking groove.

Claims (5)

A cylindrical tool holder into which a tool is inserted, a tool holding position that is pivotally attached to the tool holder, protrudes forward, and can be locked with the tool, and is tilted by a predetermined angle from the tool holding position. A tool retainer for an impact tool comprising a retainer that can rotate between a holding release position for releasing the lock with the tool,
A ring member is rotatably mounted behind the retainer on the tool holder so that the retainer can be rotated around the ring member in contact with or close to the proximal end of the retainer at the tool holding position. A lock part capable of preventing movement is provided, and the lock part is moved by a rotation operation of the ring member, so that the lock of the retainer rotation at the tool holding position and the release thereof can be selected. A featured tool retainer for impact tools. 2. The tool retainer for an impact tool according to claim 1, wherein the ring member is provided with urging means for urging and rotating so that the lock portion is positioned to lock the rotation of the retainer. A cylindrical tool holder into which a tool is inserted, a tool holding position that is pivotally attached to the tool holder, protrudes forward, and can be locked with the tool, and is tilted by a predetermined angle from the tool holding position. A tool retainer for an impact tool comprising a retainer that can rotate between a holding release position for releasing the lock with the tool,
A lock button along a side surface of the tool holder is pivotally mounted behind the retainer shaft attachment portion of the tool holder so that front and rear ends thereof can swing by a tangential pin of the tool holder , and the lock button An urging means for pressing the front end of the lock button against the base end of the retainer is provided, and a cut-out portion is formed at the base end of the retainer to which the front end of the lock button can be fitted at the tool holding position. By pushing the rear end or releasing the rear end, the front end is fitted to and detached from the cut portion of the retainer, and the lock of the retainer rotation at the tool holding position and the release thereof can be selected. A featured tool retainer for impact tools. A cylindrical tool holder into which a tool is inserted, a tool holding position that is pivotally attached to the tool holder, protrudes forward, and can be locked with the tool, and is tilted by a predetermined angle from the tool holding position. A tool retainer for an impact tool comprising a retainer that can rotate between a holding release position for releasing the lock with the tool,
A lock button that is urged outwardly by the urging means is provided to be able to project and retract behind the retainer shaft-attached portion of the tool holder, while the tool holding position is provided on the back side of the proximal end of the retainer. And forming a recess into which the front portion of the lock button can be fitted, and at a position on the rear side of the front portion of the lock button that does not interfere with the rotation trajectory of the proximal end of the retainer, higher than the front portion. And forming a rear portion having a height equal to or lower than the outer surface of the retainer at a projecting position where the front portion is fitted into the recess , and pressing the lock button using the rear portion or releasing the front portion. the parts by Hamada' against the recess of the retainer, to-for impact tool, characterized in that the locking of the rotation of the retainer in the tool holding position and can select the release and A retainer. Provided between the tool holder and the lock button is a restricting means for restricting the protruding position of the lock button so that the lock button and the retainer are not in contact with each other at the protruding position of the lock button that fits into the recess of the retainer. The tool retainer for impact tools according to claim 4.

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