JPH03136706A - Tool chuck - Google Patents

Abstract

PURPOSE:To fasten a chuck by a manual force without using a chuck handle with a compact arrangement by providing such an arrangement that a manual torque is amplified by a mechanism in which an input ring, a stationary ring and an output ring are formed in a ring-like shape, and loosening is prevented by mesh urged by a resilient member. CONSTITUTION:No load caused by clamping of a tool 10 is applied to chuck pawls 12 at the initial stage of rotation of a manipulation ring 18 so that an output ring 20, an input ring 21 and a stationary ring 22 are rotated as one unit body so that the rotation of the manipulation ring 18 directly rotates a thread ring 15 which therefore feeds the pawls 12. When the pawl 12 makes contact with the tool 19 so as to apply a load, the output ring 20 and the input ring 21 push the stationary ring 22 rearward so that pressure contact surfaces 28, 29 are pressed against each other while balls 25 roll, and accordingly, the input turns into a high torque output which is then transmitted to the output ring 20 so as to clamp the tool 19. When the tool 19 is removed, by rotating the manipulation ring in a loosening direction, the pawls 12 is loosened so that a backlash of the thread ring 15 is eliminated, and accordingly, a resilient ring 33 pushes back the stationary ring 22 so that the press-contact between the pressure contact surfaces 28, 29 are released. Thus, a torque-up mechanism 17 is released so that the thread ring 15 loosens the pawls 12 in cooperation with the manipulation ring 18.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention is a tool chuck that is attached to, for example, an electric drill or an electric screwdriver, and the chuck can be operated by hand without using a chuck handle. Concerning a tightening type tool chuck.

(b) Conventional technology A tool chuck that manually tightens the chuck without using the chuck handle as described above is known, for example, from Japanese Patent Application Laid-open No. 6
There are Japanese Utility Model Publications No. 3-174804 and Japanese Utility Model Application No. 189509/1983.

(c) Problems to be solved by the invention However, when tightening a tool chuck without using a conventional chuck handle, the force is only amplified by the screw feed that moves the chuck jaws, so when using a chuck handle, It is not possible to obtain a force equivalent to tightening the chuck jaws, and although the chuck jaws are locked with a locking means to prevent the chuck jaws from loosening, it is not possible to increase the force when tightening the chuck jaws. Therefore, there is a problem in that it is not possible to work with a tool equivalent to a tool chuck that is tightened with a chuck handle.

Therefore, this invention is equipped with a unique torque-up mechanism,
The object of the present invention is to provide a tool chuck that can be compactly constructed without complicating the structure, yet can obtain sufficient tightening force.

(d) Means for Solving the Problems The first aspect of the present invention is to provide a plurality of chuck claws obliquely at the center of the tip of the chuck body so as to be able to expand and contract, and to attach the outer surface of each chuck claw to the outer surface of each chuck claw. Partial male screws are carved, a screw ring is screwed onto these partial male screws, and an operation ring fitted on the outer periphery of the screw ring is rotated to rotate the screw ring and screw the chuck claw. This is a tool chuck that clamps a tool by expanding and contracting the tool by sliding, and a torque up mechanism is interposed between the torque transmission path between the operation ring and the threaded ring, and the torque up mechanism is connected to the threaded ring. An output ring fixed to the input ring, an input ring eccentrically and loosely fitted to the operating ring, and a fixed ring fixed to the chuck body are disposed in the axial direction of the chuck body, and Rolling grooves of an inner and outer cycloid curve having a wave number difference are carved on the opposing mutual surfaces of the base and the fixed ring, and a ball is interposed between the rolling grooves, and a power source is formed between the input ring and the output ring. The tool chuck is characterized by being formed by interposing conductive balls.

Furthermore, a second aspect of the invention is the tool chuck of the first aspect, in which the means for fixing the stationary ring and the chuck body are formed by mutual pressure contact surfaces that press against each other in the direction of the load from the chuck jaws.

Furthermore, in a third aspect of the present invention, a pressure contact surface is formed in the opposing portions of the fixed ring and the chuck body to press against each other in the direction of the load from the chuck claw, and a gear tooth is formed on the circumference of the rear surface of the fixed ring. The tool chuck according to the first aspect of the invention is characterized in that an elastic body is attached to either the operation ring or the chuck body to urge and mesh with the teeth.

(E) Function According to the tool chuck of the present invention, when the operation ring is rotated in the tightening direction in order to hold the tool between the chuck jaws, the input ring is revolved and is interposed between it and the fixed ring. As the ball rolls and moves through the groove, the input ring undergoes autorotation, and this autorotation is thicker (decelerated) relative to the revolution, resulting in an output with increased torque, and this output is output to the output ring via the ball. The screw ring is rotated, the chuck jaws are fed, and the tool is tightened and clamped with a large torque.

In addition, when the fixed ring is fixed by pressing the chuck body and the pressure contact surface, rotation of the fixed ring is allowed until these are in pressure contact, so insert the tool into the enlarged chuck jaws and the chuck jaws will clamp the tool. The input ring, fixed ring,
Since the output ring rotates as one unit and no deceleration effect occurs, the rotation of the operating ring is directly transmitted to the screw ring.
The chuck jaws can be screwed quickly and the tool can be quickly brought into the clamped state.

Then, by further rotating the operation ring from this clamped state, a tightening force is applied to the chuck jaws, a load is generated on the chuck jaws, the threaded ring retreats, and this presses the fixed ring against the chuck body. When it is fixed, the aforementioned torque-up mechanism is activated to obtain high-torque tightening.

Furthermore, when the elastic body engages with the teeth of the fixed ring,
The fixed ring and the operating ring are locked, preventing the operating ring from loosening due to inertia and vibration caused by rotation of the operating ring, and maintaining firm clamping.

(F) Effects of the Invention As a result of the above, according to the present invention, the torque-up mechanism greatly amplifies the manual turning force, so the chuck can be tightened with a large force, which is equivalent to the tightening force of a chuck handle. The tool can be securely clamped by tightening.

Furthermore, the above-mentioned torque up mechanism has an input ring, a fixed ring,
Since the output ring has a structure in which three pieces are formed in a ring shape,
The structure can be easily connected to the chuck jaw, and can be constructed compactly.Although the structure is simple, it has a large torque transmission force.

In addition, loosening of the chuck due to vibrations during operation or inertia of the operating ring is prevented by the biasing engagement of the elastic body, resulting in even more secure gripping of the tool.

Furthermore, in addition to the function of preventing loosening, the elastic body described above also prevents the operation ring from being removed from the chuck body, and also acts to release the pressure contact between the chuck body and the chuck jaws when removing the tool from the chuck. By performing the function with one part, the number of parts can be reduced and the structure can be made more compact.

(g) Examples of the invention An embodiment of the present invention will be described in detail below based on the drawings.

The drawings show a tool chuck for holding tools such as drill bits and driver bits with electric drills, electric screwdrivers, etc. In FIGS. Chuck jaw 12
... are installed obliquely so that their tips converge with respect to the axis of the chuck body 11, and are slidably expandable and contractable.

That is, each chuck claw 12 is attached to the chuck body 1.
The partial male threads 14 are inserted into the sliding grooves 13 formed at an angle with respect to the axis of the first part, and the partial male threads 14 are screwed into the outer circumference of each part so that they are continuous. The screw 14... has a female screw 16 of a ring-shaped screw ring 15.
By screwing together the screw ring 15 and rotating the screw ring 15 forward and backward, the chuck claws 12 are screwed to expand and contract, thereby releasing the tool.

A torque-up mechanism 17 is fitted on the outer circumference of the screw ring 15, and an operation ring 18 is fitted on the outer circumference of the torque-up mechanism 17, and the operation ring 18 can be rotated in forward and reverse directions, that is, By rotating the tool 19 in the tightening direction or in the removing direction, the rotational force is transmitted to the aforementioned threaded ring 15 via the torque-up mechanism 17.

The torque up mechanism 17 described above is configured as follows.

That is, the mechanism 17 includes an annular output ring 20 that is press-fitted into the screw ring 15 and fixed therein, and an annular input ring 21 that is loosely fitted and held eccentrically on the operation ring 18 with a predetermined amount of eccentricity e. and a fixed ring 22 which is fixed to the rear part of the chuck main body 11 by pressure on the tapered peripheral surface,
These annular bodies are arranged in the axial direction of the chuck body 11.

On the opposing surfaces of the input ring 21 and the fixed ring 22, the input ring 21 has a rolling 7i having an internal rotation cycloid curve and an arcuate cross section.
l! 23 is carved, and a rolling groove 24 having an arcuate cross section with an epicycloid curve is carved in the fixed ring 22, and between these rolling grooves 23.24, a plurality of balls 25. ...is mediated.

As shown in FIG. 3, the amplitude of the rolling grooves 23 and 24 is set to be the same as the eccentricity e of the input ring 21, and the wave number on the input ring 21 side is 10 waves, and the wave number on the fixed ring 24 is 10 waves. The wave number on the side is set to 12 waves, and the balls 25 interposed between these...
is set to 11 or less.

When the input ring 21 with the rolling grooves 23 and 24 is subjected to revolution caused by the eccentricity e, the balls 25 and
... rolls along the rolling grooves 23 and 24, causing the input ring 21 to rotate, and this rotation is greatly decelerated relative to the revolution, so the rotational output of the input ring 21 is increased in torque. This becomes the output.

In the case of this embodiment, since the wave number of the rolling groove 23 of the input ring 21 is 10 waves, the reduction ratio is 2710 waves = 115. However, by increasing the wave number, a large reduction ratio can be obtained. For example, By setting the wave number to 40 waves, it is possible to obtain a reduction ratio of 1/20, and a large torque increase can be obtained.

In order to extract the rotation of the input ring 21 mentioned above to the output ring 20,
A plurality of balls 26 are interposed on these opposing surfaces.

That is, a recess (not shown) into which the ball 26 is inserted is formed on the input ring 21 side, and the output ring 2 opposite thereto is formed with a recess (not shown) into which the ball 26 is inserted.
A recess 27 is also formed in the output ring 20, and the recess 27 of the output ring 20 allows the ball 26 to rotate with the same eccentricity e so that power can be transmitted even if the input ring 2 is rotated eccentrically. It is formed into a concave portion as large as possible (ring shape).

In order to fix the above-mentioned fixed ring 22 to the chuck body 11, a tapered pressure contact surface 28 is formed in the center of the fixed ring 22, the diameter of which is larger on the rear end side, and also on the chuck body 11 side. When the fixed ring 21 is pressed by the backlash of the screw ring 15 (in the load direction of the chuck claws 12), the fixed ring 21 comes into pressure contact with the chuck body 11. Fixed.

A gear tooth 30 is carved on the circumference of the rear side of the aforementioned fixed ring 21, and an elastic ring 33 having a plurality of elastic bodies 32 each having a claw 31 that engages with the tooth tooth 30 is attached to the fixed ring 22. The fixing pawl 34 of the elastic ring 33 is press-fitted into the groove 35 carved in the inner peripheral surface of the operating ring 18, thereby preventing the elastic ring 33 from coming out and preventing it from rotating. I do.

A cover 36 is opposed to the rear of the operating ring 18, and its base is press-fitted and fixed to the rear of the chuck body 11.

Although the elastic ring 33 described above is fixed to the operating ring 18 side, it may be fixed to the chuck body 11 side.

In addition, the aforementioned threaded ring 15 is formed in two parts, and after being assembled to the chuck body 11, the output ring 20 is press-fitted into one body. It may be made into an integral structure by any means, such as by carving it and fixing it with screws, or by spline fitting and preventing it from coming out with an E ring.

The operation of the tool chuck 10 configured in this way will be explained.

In order to clamp the tool 19 in the chuck jaws 12, the chuck jaws 12 are thick (assuming they are open).In order to insert the tool 19 into the chuck jaws 12 and clamp the chuck jaws 12, the operating ring 18 must be tightened. rotates in the direction.

At the initial stage of rotation, no load is applied to the chuck jaws 12 due to the clamping of the tool 19, so the fixed ring 22 of the torque-up mechanism 17 is free with respect to the chuck body 11, so the output ring 20, the input ring 21. The fixed ring 22 is integrated and rotates as a unit, so that the rotation of the operation ring 18 directly becomes the rotation of the screw ring 15, and the chuck claw 12 is sent out with a fast screw feed.

When the chuck jaw 12 contacts the tool 19 and a load is generated on the chuck jaw 12, the load causes backlash in the screw ring 15, which causes the fixed ring 22 to move backward through the output ring 20 and the input ring 21. Press down.

As a result, the pressing surfaces 28 and 29 of the fixed ring 22 and the chuck body 11 are brought into pressure contact, so that the fixed ring 22 is fixed to the chuck body 11, and the torque-up mechanism 17 is brought into operation.

That is, the rotation of the operating ring 18 causes the input ring 21 to revolve, and as the balls 25 roll and move through the grooves 23 and 24 during this revolution, the input ring 21 rotates, and this rotational output decelerates the input. A high torque output is output to the output ring 20, the screw ring 15 is rotated, and the chuck jaws 12...
is sent out and clamps the tool 19 with high torque.

Note that when removing the tool 19, the operating ring 18 may be rotated in the loosening direction.

In this case, when the chuck claws 12 are loosened and there is no backlash in the screw ring 15, the elastic body 32 pushes back the fixed ring 22, so that the pressure contact between the fixed ring 22 and the chuck body 11 is released. Torque up mechanism 17
is released, the screw ring 15 rotates quickly at the same speed as the rotation of the operating ring 18, and quickly feeds the chuck claw 12 in the loosening direction.

According to this embodiment, the clamping of the tool 19 is strong because the tightening torque increased by the torque-up mechanism 17 is clamped by force, and clamping equivalent to that obtained when using a chuck handle is obtained.

Furthermore, the above-mentioned torque up mechanism 17 includes an output ring 20,
Since the input ring 21 and the fixed ring 22 have a ring-shaped structure, the structure can be easily connected to the chuck claw 12, and the structure can be made compact, and the structure is simple. However, it has a large torque transmission force.

In addition, loosening of the operating ring 18 and the chuck jaws 12 due to vibrations during operation is prevented by the biasing engagement of the elastic body 32, so that the tool 19 can be held even more firmly.

Furthermore, the above-mentioned elastic body 32 has the function of preventing loosening.
Prevent the operation ring 18 from being removed from the chuck body 11,
Furthermore, when the tool 19 is removed from the chuck jaw 12, the pressure contact between the chuck body 11 and the chuck jaw 12 is released, and three functions are performed in one part, thereby reducing the number of parts and making the structure more compact. be able to.

In the above-mentioned embodiment, the chuck claw 12 is screwed by the screw ring 15 on its outer periphery, but the chuck claw 12 is screw-fed using the screw ring 15 on its outer periphery.
Since the torque-up mechanism 17 of the present invention can also be installed in a screw-feed type chuck jaw, the present invention, including other configurations, is not limited to only the configuration of the embodiment.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a sectional view of a tool chuck, FIG. 2 is an exploded perspective view of a torque-up mechanism, and FIG. 3 is an explanatory diagram of a rolling groove. 10... Tool chuck 11... Chuck body 12... Chuck jaw 15... Screw ring 17... Torque up mechanism 18... Operation ring 20... Output ring 21... Input ring 22 ... Fixed ring 23.24 ... Rolling groove 25.26 ... Ball 28.29 ... Pressure contact surface 30 ... Teeth ridge 32 ... Elastic body 33 ... Elastic ring 10 ... Tool check 23.24... Turning force tlJ reference Fig. 3 36-

Claims (3)

[Claims] (1) A plurality of chuck claws are provided obliquely at the center of the tip of the chuck body so that they can be expanded and retracted, and a partial male screw is carved on the outer surface of each of these chuck claws,
A screw ring is screwed onto these partial male screws, and by rotating an operating ring fitted on the outer periphery of the screw ring, the screw ring is rotated and the chuck jaws are expanded and contracted by screw feeding, thereby operating the tool. A tool chuck for clamping, wherein a torque up mechanism is interposed between the torque transmission path between the operation ring and the screw ring, and the torque up mechanism is connected to the output ring fixed to the screw ring and the operation ring. An input ring eccentrically fitted and held in the ring and a fixed ring fixed to the chuck body are disposed in the axial direction of the chuck body, and mutual faces of the input ring and the fixed ring are opposed to each other. A rolling groove having an inner and outer cycloidal curve having a wave number difference is carved, a ball is interposed between the rolling groove, and a power transmission ball is interposed between the input ring and the output ring. tool chuck. (2) The tool chuck according to claim 1, wherein the means for fixing the fixed ring and the chuck body are formed by mutual pressure contact surfaces that press against each other in the direction of the load from the chuck jaws. (3) mutually between the opposing parts of the fixed ring and the chuck body;
A pressure contact surface that presses in the direction of the load from the chuck jaw is formed, and a tooth is formed on the circumference of the rear side of the fixed ring, and an elastic body that is biased and meshed with the tooth is attached to the operating ring or the chuck body. The tool chuck according to claim 1, wherein the tool chuck is attached to one side of the tool chuck.