JPH0829444B2 - Tool chuck - Google Patents

Description

Description: (a) Technical field to which the present invention pertains The present invention relates to a tool chuck that is mounted on a tool such as an electric drill or an electric river and that enables a tool to be tightened without using a chuck handle. Regarding

(B) Conventional Technology Conventionally, as the tool chuck described above, for example, a nut ring loosely fitted in the chuck body is normally and reversely rotated by rotationally operating an operation ring, and a plurality of nut rings screwed together are provided. There is a tool chuck (Japanese Utility Model Laid-Open No. Sho 63-189509) in which each chuck claw is expanded and contracted in the tool clamping direction to clamp and fix the tool.

(C) Problems to be Solved by the Invention However, in the above-mentioned tool chuck, since the rotational force of the operation ring by manual operation is converted into the direction of the expansion / contraction operation of the plurality of chuck claws via the screw feeding mechanism, It is structurally difficult to obtain a tightening force equivalent to that when using a handle, and it is structurally difficult to obtain a tightening force higher than the torque amplified by the screw feed mechanism. It has a problem that it is apt to rattle and loosen and is not applicable to use conditions requiring high torque.

In view of the above problems, an object of the present invention is to provide a tool chuck that can firmly tighten and fix a tool only by manually rotating an operation ring, and that can easily perform tightening, fixing and releasing of the tool. To do.

(D) Means for Solving the Problems The present invention is characterized in that a torque-up mechanism provided between transmission paths of an operation ring and a nut ring is loosely fitted to the operation ring with an input / output ring eccentric. A fixing ring is loosely fitted on the center of the chuck to the center of the chuck, and rolling grooves having inner and outer cycloid curves having a wave number difference are engraved on the facing surfaces of the input / output ring and the fixing ring, and balls are formed between the rolling grooves. The input / output ring and the nut ring are rotatably held, and a pressure contact portion, which is pressed and fixed by a reaction force due to the tightening of the nut ring, is provided on the surface facing the chuck body and the fixing ring, and the input / output ring and the nut ring are connected so that power can be transmitted. It is characterized in that it is a tool chuck configured as described above.

(E) Operation According to the tool chuck of the present invention, by rotating the operation ring in the direction in which the tool is clamped, a load due to the clamping of the tool is applied to the chuck claws at the initial stage of rotation. Since the fixing ring that constitutes the torque-up mechanism is rotatable with respect to the chuck body, the operation ring, the input / output ring, and the fixing ring rotate integrally with the transmission load, and the nut The screw feed of the ring quickly and tightly slides the chuck claws to clamp and fix the tool.

Furthermore, when the operating ring is rotated in the tightening direction and the tool is clamped by the chuck claws, a load is generated on the chuck claws and the nut ring retracts due to the reaction force due to the tightening. The pressure-up mechanism causes a deceleration action by pressing and rotatingly fixing.

That is, when the operation ring is rotated to revolve the input / output ring, the ball rolls along the rolling groove formed on the facing surface of the input / output ring and the fixed ring, and the ball rolls. As the I / O ring rotates,
Due to the wave number difference of these rolling grooves, the rotation output of the input / output ring decelerates the input and becomes a high torque output, the nut ring rotates, and the chuck jaws are screw-fed to clamp and fix the tool with high torque. .

(F) Effect of the Invention As a result of the above, according to the present invention, since the turning force of the operating ring is reduced by the torque-up mechanism when the tool is held, the turning force of the operating ring is higher than that directly transmitted to the nut ring. A torque can be obtained, and the tool can be tightened and fixed with a torque according to the operating conditions simply by rotating the operating ring in the tightening direction.The torque-up mechanism is composed of the input / output ring and the fixed ring. Since it is easy to assemble to the chuck body,
Although the structure is simple, a large torque increasing effect can be obtained.

Moreover, the operation ring, the input / output ring, and the fixing ring are integrally rotated during the rotation operation until the tool is tightened and fixed and during the rotation operation after the tightening is released. By rotating the ring, a plurality of chuck claws can be rapidly expanded / contracted, and the tool can be clamped / fixed or unlocked, which is excellent in operability.

(G) Embodiment of the Invention One embodiment of the present invention will be described in detail below with reference to the drawings.

The drawing shows a tool chuck for holding a tool such as a drill bit or a driver bit in a tool such as an electric drill or an electric screwdriver. In FIG. 1, the tool chuck 1 is formed in a cylindrical shape. On the outer peripheral surface of the central portion of the chuck body 2, three guide holes 3 are formed in an oblique direction gathering toward the center portion on the tip side, and three chuck claws 4 are formed in these guide holes 3. It is inserted so that it can be expanded and contracted.

On the outer peripheral surface of the central portion of the chuck body 2 described above, a part of each of the three guides 3 is cut out in the circumferential direction to form an annular cutout portion 5.
Is formed, and a nut ring 6 that can be split into two is loosely fitted in the annular notch 5, and the female screw 6a threaded on the inner peripheral surface of the nut ring 6 and the outer periphery of the rear end of the chuck claw 4 are formed. The male screw 4a screwed on the surface is screwed together.

The above-mentioned nut ring 6 is a ring formed by dividing into two.
Both ends of 6b, 6b are opposed to each other and are loosely fitted into the annular notch 5,
A sleeve 7 is press-fitted into the outer peripheral surfaces of the rings 6b, 6b on the tip side to be integrally fixed, and by rotating the nut ring 6 forward and backward, the three chuck claws 4 ... Is screw-fed in the expansion / contraction direction along the
The tool A is clamped and fixed and released by.

The operation ring 8 formed in a cylindrical shape is rotatably loosely fitted on the outer peripheral surface of the central portion of the chuck body 2 described above, while the cylindrical outer shape is formed on the outer peripheral surface of the rear end portion of the chuck body 2. The ring 9 is integrally fitted and fixed.

A torque increasing mechanism 10 for transmitting the turning force of the operating ring 8 to the nut ring 6 is provided between the transmission paths of the operating ring 8 and the nut ring 6 described above.

The torque-up mechanism 10 includes an input / output ring 11 loosely fitted to the inner peripheral surface of the operation ring 8 and a fixed ring 12 loosely fitted to the inner peripheral surface of the operation ring 8 and the outer peripheral surface of the chuck body 2.
Composed of and.

As shown in FIG. 2, the inner peripheral surface of the input / output ring 11 on the distal end side is loosened on the outer peripheral surface of the eccentric portion 14 formed on the inner peripheral surface of the central portion of the operation ring 8 via the ball bearing 13, as shown in FIG. It is fitted.

As shown in FIG. 2, the outer peripheral surface of the eccentric portion 14 is formed around an axial center C, which is eccentric with respect to the axial center B of the chuck body 2 by the dimension e.

The inner peripheral surface on the rear end side of the input / output ring 11 is meshed with the outer peripheral surface of the sleeve 7 press-fitted and fixed to the nut ring 6 via the gap coupling 15 so as to be able to transmit power.

That is, this gap coupling 15 is an input / output ring.
A gear 16 engraved on the inner peripheral surface of the rear end side of 11 and a gear 17 engraved on the outer peripheral surface of the sleeve 7 facing the inner peripheral surface are meshed with each other in a loosely fitting state allowing eccentricity of the e dimension. .

As shown in FIG. 3, on the opposing surfaces of the input / output ring 11 and the fixed ring 12, a rolling groove 18 having an arcuate cross section is engraved on the input / output ring 11 side by an adduction cycloid curve, and A rolling groove 19 having an arcuate cross section is engraved on the fixed ring 12 side by an abduction cycloidal curve, and a large number of balls 20 are rollably held between these rolling grooves 18, 19.

As shown in FIG. 4, the amplitude of the rolling grooves 18 and 19 is set to the same amount as the eccentric amount e of the input / output ring 11,
In addition, the wave number of the rolling groove 18 on the input / output ring 11 side is engraved to 10 waves, and the wave number of the rolling groove 19 on the fixed ring 12 side is engraved to 12 waves, and is held between these rolling grooves 18 and 19. The number of balls 20 is set to 11 or less.

In the input / output ring 11 with the rolling groove 18 thus formed,
When a revolution caused by the eccentricity e of the eccentric portion 14 is given, the ball 20 rolls along the rolling grooves 18 and 19 to cause the input / output ring 11 to rotate, and this rotation is greatly decelerated with respect to the revolution. Therefore, the rotation output of the input / output ring 11 becomes an output with increased torque.

In the case of this embodiment, since the rolling groove 18 of the input / output ring 11 has 10 waves, the reduction ratio is 2/10 waves = 1/5, but a large reduction ratio can be obtained by increasing the number of waves. For example, it is possible to set the wave number to 40 waves and obtain a reduction ratio of 1/20, and a large torque increasing action can be obtained.

The fixed ring 12 described above is a ring 12 that is configured to be separable.
A plurality of connecting pins 21 are press-fitted into the facing surfaces of a and 12b to be fixedly connected, and a thrust bearing 22 is rotatably held between the facing surfaces of the ring 12b on the rear end side and the nut ring 6. .

On the inner peripheral surface of the ring 12b constituting the above-mentioned fixed ring 12, a tapered surface 23 having a diameter gradually increasing toward the rear end side is formed, and on the outer peripheral surface of the central portion of the chuck body 2 facing the tapered surface 23. The tapered surface 24 is formed so that its diameter gradually increases toward the rear end side.

When the tool A is clamped, the tapered surfaces 23, 24 are pressed against each other by the nut ring 6 being retracted by the reaction force due to the tightening, so that the fixing ring 12 is fixed to the chuck body 2.
Rotate and fix.

A fixing ring is provided on the inner peripheral surface of the operation ring 8 on the rear end side.
The spring ring 2 faces the rear end face of the ring 12b that constitutes 12
5 is inserted and the elastic piece 26 formed on the inner peripheral edge of the spring ring 25 is engaged with the notch surface 27 formed on the rear end surface of the ring 12b so that the notch is formed when the operation ring 8 is rotated. The fixing ring 12 is urged in a direction to release the pressure contact between the tapered surfaces 23 and 24 while giving a touch.

A retaining ring 28 is press-fitted and fixed to the rear side of the spring ring 25, and the retaining ring 28 prevents the spring ring 25 from retaining and rotating.

Assuming that the illustrated embodiment is configured as described above,
The tightening operation and the releasing operation of the tool chuck 1 will be described.

First, when the tool A is clamped by the three chuck claws 4 ..., As shown in FIG. 2, the holding ring 9 is rotationally fixed, and the operating ring 8 is tightened in the tightening direction D (solid arrow direction).
When the tool is rotated, the load due to the tool A being clamped is not applied to each of the three chuck claws 4 ... Since it is rotatable with respect to the main body 2, the operation ring 8, the input / output ring 11, and the fixed ring 12 are integrally rotated by a transmission load, and the nut ring 6 is screw-fed to rotate the three rings. The chuck claws 4 ...

Next, when each of the three chuck claws 4 comes into contact with the tool A and a clamping load is applied, the nut ring 6 is retracted by a reaction force due to the tightening, and the fixing ring 12 is moved rearward through the thrust bearing 22. When the fixed ring 12 and the chuck body 2 are integrally rotated and fixed by pressing the tapered surfaces 23 and 24 of the fixed ring 12 and the chuck body 2 into contact with each other, the speed is reduced by the torque-up mechanism 10. The action occurs.

That is, when the input / output ring 11 revolves when the operation ring 8 is rotated, the input / output ring 11 and the fixed ring 12 are rotated.
Ball 20 along the rolling grooves 18 and 19 engraved on the surface facing
And the rotation of the ball 20 causes the input / output ring 11 to rotate, and due to the wave number difference between the rolling grooves 18 and 19, the rotation output of the input / output ring 11 reduces the input to a high torque output. Then, the nut ring 6 rotates and the three chuck claws 4 are screw-fed to clamp and fix the tool A with high torque.

When removing the tool A, the operation ring 8 may be rotated in the loosening direction E (dotted line direction).

In this case, when the three chuck claws 4 ... Retreat and the reaction force due to tightening does not act on the nut ring 6, the fixing ring 12 is moved forward by the urging force of the spring ring 25 and the fixing ring 12 Surface of the chuck and the chuck body 2 23,2
Since the pressure contact fixing by 4 is released, the torque up mechanism 1
The operation ring 8, the input / output ring 11, and the fixed ring 12 rotate integrally without generating the deceleration action due to 0, and the reverse screw feed of the nut ring 6 rapidly moves the three chuck claws 4 ... The tool A is extended and slid to release the clamped fixation of the tool A.

As described above, when the tool A is clamped, the turning force of the operation ring 8 is decelerated by the torque increasing mechanism 10.
A higher torque can be obtained than directly transmitting the turning force of the operation ring 8 to the nut ring 6, and the tool A can be tightened and fixed only by rotating the operation ring 8 in the tightening direction. Since the torque increasing mechanism 10 is composed of the fixing ring 12, the assembling to the chuck body 2 is easy, and the structure is simple and a large torque increasing action is obtained.

Moreover, the operation ring 8 is rotated during the rotating operation until the tool A is tightened and fixed and during the rotating operation after the tightening is released.
Since the input / output ring 11 and the fixed ring 12 are integrally rotated, the screw feeding of the nut ring 6 rapidly expands and contracts each of the three chuck claws 4 to fix or fix the tool A. It can be released and has excellent operability.

In the correspondence between the configuration of the present invention and the above-described embodiment, the pressure contact portion of the present invention corresponds to the tapered surfaces 23 and 24 of the embodiment, but the present invention is limited to the configuration of the above-described embodiment. It is not something that will be done.

For example, the inner peripheral surface of the operation ring 8 is formed eccentrically with respect to the axial center B of the chuck body 2 by the dimension e, and the input / output ring 11 is rotatably mounted on the inner peripheral surface of the operation ring 8. By fitting, the input / output ring 11 can be revolved by the turning operation of the operation ring 8 as described above.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a vertical sectional side view of a tool chuck, FIG. 2 is a vertical sectional view of the II-II portion shown in FIG. 4 is an exploded perspective view of FIG. 4, and FIG. 4 is an operation explanatory view of the rolling groove. A: Tool, 1 ... Tool chuck, 2 ... Chuck body, 4 ... Chuck claw, 6 ... Nut ring, 8 ... Operation ring, 10 ... Torque increasing mechanism, 11 ... Input / output ring, 12 ... Fixed ring , 18,19 …… Rolling groove, 20… Ball 23,24 …… Tapered surface

Claims (1)

[Claims] 1. A chuck main body holds a plurality of chuck claws in a central portion on the front end side so that the chuck claws can be expanded and contracted, and a nut ring screwed to each of the chuck claws is rotated by an operation ring to perform a chuck claw. Is a tool chuck for expanding and contracting, and a torque-up mechanism is provided between the transmission paths of the operation ring and the nut ring, and the torque-up mechanism is loosely fitted by eccentricizing the input / output ring with respect to the operation ring. Then, a fixing ring is loosely fitted to the chuck main body on the coaxial center, and rolling grooves of an inner-outer cycloid curve having a wave number difference are engraved on the facing surfaces of the input / output ring and the fixing ring, and the rolling groove gap is formed. The ball is held in a rollable manner, and a press-contact portion is provided on the surface facing the chuck body and the fixing ring, which is press-contacted and fixed by a reaction force due to the tightening of the nut ring. Tool chuck constructed by the ring and the nut rings linked in a power transmission.