JP2533658B2 - Fastener - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a tightening tool called a chuck provided for holding a tool such as a drill bit or a driver bit in an electric drill or an electric screwdriver.

[Prior art]

There is a fastener that allows the tool to be attached and detached without using the chuck handle. In this type of tightening tool, the relative rotation between the shaft and the sleeve causes the tightening claws to move in the radial direction. Therefore, the shaft and the sleeve generated when the shaft is rotated to perform the work. There is a problem that the relative rotation between and causes the nail to be loosened. For this reason, conventionally, in this type of tightening tool, a locking means for preventing relative rotation between the shaft and the sleeve has been incorporated. For example, the actual exploitation sho 63-158711
In the publication, a ratchet plate that rotates integrally with the shaft is provided, and ratchet teeth that engage with the ratchet plate are formed on the end surface of the sleeve. Due to the engagement of the ratchet teeth, the sleeve is rotated unintentionally with respect to the shaft. It has been made to prevent it from happening.

[Problems to be Solved by the Invention]

However, in the above-mentioned conventional example, unlocking for removing the tool is performed by moving the handle mounted on the sleeve in the axial direction to separate the ratchet plate from the sleeve, and the operability is poor. I have a problem. In this regard, the applicant of the present application has already filed Japanese Patent Application No. 63-16
No. 7291 (Japanese Patent Publication No. 4-60762) proposes a tightening tool that is unlocked simply by rotating the handle relative to the shaft. Since the lock can be released and the pawl can be loosened only by the operation of rotationally driving the shaft, the operability is excellent. However, since the ratchet pawl supported by the pivot was used as the locking means, the load applied to the ratchet pawl is large, and the operation of loosening the pawl by rotating the handle with respect to the shaft while releasing the lock. The operation force was heavy and sometimes the user felt stuck. The present invention has been made in view of the above points, and an object of the present invention is to lock and unlock only by rotating operation. Therefore, lock and unlock using rotation of a shaft by an electric tool is also possible. Moreover, it is an object of the present invention to provide a tightening tool that has a light operating force and does not cause a feeling of being caught.

[Means for Solving the Problems]

Thus, the tightening tool according to the present invention includes a shaft to which power is transmitted, a sleeve that is rotatable with respect to the shaft, and a tightening claw that moves in the radial direction as the sleeve rotates with respect to the shaft. A tightening tool comprising: locking means for locking rotation of the sleeve with respect to the shaft; and unlocking means for unlocking the locking means, the locking means comprising a first disc rotationally fixed to the shaft, Second rotation fixed to sleeve
The two discs, which are composed of a disc and at least one of which is capable of axial movement, have a large number of ratchet teeth on the opposite surfaces, and the ratchet teeth of the two discs are coupled to each other for unidirectional rotation. Are freely rotatable relative to each other and are coupled to each other for rotation in the other direction, and are urged in a direction in which they are engaged with each other by a spring that urges in the axial direction, and the releasing means rotates with respect to the sleeve. Formed by a release ring which is fixed to the sleeve with a required play in the direction and which, by rotation in this play with respect to the sleeve, pulls the discs apart against the spring bias. There is. [Operation] According to the present invention, only by causing relative rotation between the release ring and the shaft, the release ring rotates within a play range with respect to the second disc, and the second disc is spring-loaded. Unlocking the lock due to improper spring engagement of the first disc rotatably fixed to the shaft and the second disc rotatively fixed to the sleeve for axial movement against the force. You can [Embodiment] The present invention will be described in detail below with reference to illustrated embodiments.
As shown in FIG. 1, the metal cylindrical shaft 1 whose rear end is connected to the drive shaft, which is the output portion of the electric tool, by the collar 17 and the set screw 18 disposed inside is as shown in FIG. , The uneven surface by knurling on the outer peripheral surface of the rear end 11
Is provided, and a female screw 13 is cut on the inner peripheral surface of the front end portion where the flange 12 is formed, and the float screw 3 is screwed in. A sleeve 2 is attached to the outer periphery of the front end of the shaft 1. A groove 20 is formed on the outer peripheral surface of the sleeve 2,
Screws 22 are formed on the outer peripheral surface on the front end side, and the front end surface is uneven.
21 is formed, a taper sleeve 26 is attached to the tip end by the connection with the screw 22, and a guide block 23 is arranged in the taper sleeve 26.
In this guide block 23, the unevenness 25 at the rear end is engaged with the unevenness 21. That is, the sleeve 2 and the taper sleeve
The 26 and the guide block 23 are designed to rotate integrally. Each of the plurality of claws 4 for tightening a tool such as a drill bit or a driver bit has an inclined surface on the outer surface and has an engaging piece 40 at the rear end. Engagement groove 30 provided on the float screw 3
Is engaged with. In addition, each claw 4 is housed in a slit 24 formed in the above-mentioned conical metal-made guide block 23, and a wing piece is formed on the outer conical surface of the guide block 23.
41 is engaged. On the other hand, a release ring 5, a first circular plate 6, a second circular plate 7, and a leaf spring 8 are arranged in this order from the rear on the outer periphery of the shaft 1 on the rear end side. When,
It is lined up with a stop ring 19 attached to the shaft 1. The first disc 6 has a plurality of pieces 62 projecting from the inner peripheral edge thereof along with the outer peripheral surface of the shaft 1 so that the posture with respect to the shaft 1 is restricted and the engaging teeth provided on a part of the inner peripheral edge. By engaging 61 with the uneven surface 11 on the outer peripheral surface of the shaft 1, the shaft 61 is rotated integrally with the shaft 1. In addition, the engaging teeth 61 for rotationally fixing the shaft 1
As is apparent from FIG. 5, the reason why a part is not provided all around the inner peripheral edge but is provided only partially is as follows. That is, the uneven surface 11 is formed by knurling, which is an inexpensive process, without performing coft-like processes such as spline processing on the shaft 1.
When the concave and convex surfaces 11 are formed, the shape of the uneven surface 11 inevitably changes slightly.
This is because if the above is provided on the first disc 6, it may not be possible to engage them. On the other hand, as shown in FIG. 4, the second disc 7 is fitted with a projecting piece 71 projecting from the outer peripheral edge in the groove 20 of the sleeve 2 so as to rotate integrally with the sleeve 2, and The projection 73 has a groove 73 on the outer peripheral side and a plurality of notches 72 on the outer peripheral edge. The both discs 6 and 7 have a large number of ratchet teeth 60 and 70 respectively on the surfaces facing each other, and the engagement between the ratchet teeth 60 and 70, which are provided in a two-row annular shape, causes the first and second ratchet teeth 60 and 70 to engage with each other. As shown in FIG. 6, the release rings 5 are arranged such that relative rotation about the rotation in the direction shown by the arrow is freely possible and that they are connected to each other about the rotation in the other direction. The engaging piece 51, the tongue piece 52, and the projection 53 are formed as protruding in the axial direction. Here the engaging piece 51
Engages with an engaging groove 55 formed on the inner peripheral surface of the handle 50 arranged on the outer periphery thereof to integrate the release ring 5 and the handle 50, and the tongue 52 is the second disc. 7 is located in the groove 73 to mutually restrict the movements of the release ring 5 and the second disc 7 in the rotational direction, and the protrusion 53 having a triangular shape is the second disc. The notch 72 of 7 is freely engageable. Since the width of the tongue piece 52 is narrower than the width of the groove 73, the movement of the release ring 5 and the second disc 7 in the rotational direction is restricted with respect to the second disc 7. Has some play in the direction of rotation. That is, the second
Since the disc 7 is integral with the sleeve 2 in terms of its rotation, the handle 50 and the release ring 2 are fixed to the sleeve 2 with a certain play in the rotational direction with respect to the sleeve 2. become. The leaf spring 8 is provided with a plurality of spring pieces 81 whose one surface is in contact with the rear end surface of the sleeve 2 and which biases the second disk 7 toward the first disk 6 side. The release ring 5, the first and second discs 6 and 7, and the leaf spring 8 are all manufactured by press working on sheet metal parts to reduce costs. Further, the reason why each ratchet tooth 60, 70 is formed in a two-row annular shape is to increase the number of ratchet teeth 60, 70 and to reduce the load on each ratchet tooth 60, 70 when locked. As shown in FIGS. 4 and 5, the ratchet teeth 6 on the inner peripheral side are provided.
The 0, 70 and the ratchet teeth 60, 70 on the outer peripheral side are provided so as to be displaced in the circumferential direction in order to increase the strength of these discs 6, 7 against twisting. Now, as shown in FIGS. 8 and 11, the two discs 6 and 7 are attached by the leaf spring 8 when the protrusion 53 of the release ring 5 fits into the notch 72 of the second disc 7. Since the ratchet teeth 60, 70 are brought closer to each other by the force and engaged with each other, the rotation of the chaft 1 with respect to the sleeve 2 is possible only in the direction shown by the arrow in FIG. The rotation in the direction causes the float screw 3 screwed with the shaft 1 to move forward to move the claws 4 forward. As a result, the claws 4 that position the blade 41 between the guide block 23 and the inner peripheral surface of the taper sleeve 26 gather at the center in the radial direction and tighten the tool. The rotation in this direction is the same as when the screw is tightened by the tool. When loosening the screw, the shaft 1 may be rotated in the direction opposite to the arrow. In this case, there is no relative rotation between the shaft 1 and the sleeve 2 due to the engagement of the ratchet teeth 60, 70 of the first disk 6 and the second disk 7, so that the pawl 4 expands. There is no chance that it will end up. The removal of the tool can then be performed by rotating the shaft 1 in the direction opposite to the arrow while holding the handle 50. That is, when the handle 50 is gripped and the shaft 1 is rotated in the above-mentioned direction, initially both discs are
By engaging the ratchet teeth 60, 70 of 6, 7 with each other, the sleeve 2
On the other hand, the handle 50, which is rotationally connected through the release ring 5, performs relative rotation with respect to the sleeve 2 within the play range. When this rotation occurs, as shown in FIGS. 9 and 10, the protrusion 53 protruding from the release ring 5 comes out from the notch 72, and the second disc 7 is resisted against the leaf spring 8. In order to move it to the sleeve 2 side, the second disc 7 disengages the ratchet teeth 60, 70 from the first disc 6 and therefore, the handle after that.
Only the shaft 1 rotates with respect to the sleeve 50 and the sleeve 2, and the relative rotation between the sleeve 2 and the shaft 1 causes the float screw 3 to retreat and open the claw 4. When the rotation of the shaft 1 is stopped and the hand is released from the handle 50, the protrusion 53 is formed in the notch 72 of the second disc 7 because of the biasing by the leaf spring 8 and the protrusion 53 having a triangular shape. Re-engage.

【The invention's effect】

As described above, in the present invention, only by causing relative rotation between the release ring and the shaft, the release ring rotates within the play range with respect to the second disc, and the second disc is spring-loaded. The lock is released by the spring-biased engagement of the first disk rotationally fixed to the shaft and the second disk rotationally fixed to the sleeve in order to move in the axial direction against the bias. If the shaft is rotated by an electric tool, the shaft can be locked and unlocked simply by rotating the shaft while holding the release ring, and the lock is the first disc. And ratchet teeth formed in large numbers on the second disc and the second disc, respectively, and the load on each ratchet tooth is small, but the locking strength can be high and the release ring can rotate. On the other hand To release the lock by moving the plate in the axial direction, it is possible to reduce the operating force of the time of unlocking, it is obtained a no smooth release operation caught feeling.

[Brief description of drawings]

1 is an exploded perspective view of an embodiment of the present invention, FIG. 2 is a cutaway front view of the same, FIG. 3 is a rear view of the same, FIG. 4 is a rear view of a second circular plate of the same, and FIG. Is a rear view of the same first disk, FIG. 6 is a rear view of the release ring of the same, FIG. 7 is a sectional view taken along line A-O in FIG. 3, and FIGS. B-O in the figure
Sectional views and partial horizontal sectional views, FIGS. 9 (a) and 9 (b) are B-O sectional views and partial horizontal sectional views, FIG. 10 and FIG.
Fig. 11 is a rear view of the second disk showing the same operation as above.
Is a shaft, 2 is a sleeve, 4 is a claw, 5 is a release ring,
6 is a first disc, 7 is a second disc, 8 is a leaf spring, 52 is a tongue piece,
53 is a protrusion, 60 and 70 are ratchet teeth, 72 is a notch, and 73 is a groove.

Claims (3)

(57) [Claims] 1. A shaft to which power is transmitted, a sleeve rotatable with respect to the shaft, a tightening claw that moves in a radial direction with rotation of the sleeve with respect to the shaft, and a sleeve with respect to the shaft. A tightening tool comprising lock means for locking rotation and release means for unlocking the lock means, the lock means comprising:
The first and second circular plates, which are rotationally fixed to the shaft, and the second circular plate, which is rotationally fixed to the sleeve, and at least one of which is axially movable, have both discs on opposite surfaces. Each has a large number of ratchet teeth, the ratchet teeth of both discs are engaged to allow relative rotation about one direction of rotation, and are connected to each other about rotation of the other direction. The releasing means are biased in a direction to engage with each other by a biasing spring, and the releasing means is fixed to the sleeve with a required play in the rotational direction with respect to the sleeve, and rotation in this play with respect to the sleeve causes the two circles to rotate. A fastener formed by a release ring that separates the plate against the spring bias. 2. The axially movable disc of the first disc and the second disc is provided with a notch, and a release ring formed of the disc projects in the axial direction. The tightening tool according to claim 1, further comprising a protrusion that moves the disc in the axial direction by moving in and out of the notch. 3. A second disc fixed to the sleeve by rotation is provided with a groove for receiving a tongue projecting axially from the release ring, and the groove width is made larger than the width of the tongue. Fastener according to claim 1, characterized in that the required play in the direction of rotation of the release ring with respect to is formed.