JP2652727B2 - Tool chuck - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool chuck for holding a tool such as a drill bit of an electric drill and a driver bit of an electric screwdriver, and more particularly, to a tightening operation without using a chuck handle. For tool chuck.

[0002]

2. Description of the Related Art Conventionally, as the above-mentioned tool chuck,
For example, the operation ring is rotated to rotate the nut ring loosely fitted to the chuck body, and the rotation of the nut ring causes a plurality of chuck claws to be screw-fed in the tool holding direction, and these chuck claws are rotated. Tool chuck that fixes the tool with a screw (see JP-A-63-189509)
There is.

[0003]

However, the above-mentioned tool chuck amplifies the rotational force of the operation ring by manual operation by screw feed of the nut ring, and converts the plurality of chuck claws in the direction of expanding and contracting operation. However, since it is difficult to obtain a tightening force equivalent to the case using a chuck handle and it is structurally difficult to obtain a tightening force higher than the torque amplified by the screw feed mechanism, the tool and each chuck are required during operation. It is easy for rattling and looseness to occur with the nail,
It has a problem that it is not applicable to use conditions requiring high torque.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide a tool chuck which can firmly tighten and fix a tool only by rotating an operation ring, and can easily perform fastening and fixing operations. .

[0005]

According to the present invention, a torque-up mechanism is provided between an operating ring of a tool chuck and a nut ring to reduce the rotation of the operating ring, increase the torque, and transmit the torque to the nut ring. The torque-up mechanism is formed by arranging an input / output ring at the center along the axis of the chuck body, a corresponding portion of the nut ring at the tip of the chuck, and a fixing ring at the rear end of the chuck. ,
The input / output ring is rotatably held on the inner peripheral surface of the operation ring at a predetermined angle with respect to the axial center line of the chuck main body, and the input / output ring faces the corresponding portion of the nut ring. A gear having a difference in the number of teeth is engraved on the end face, and a part of the gears is meshed with each other, the fixing ring is loosely fitted to the outer peripheral portion of the chuck body, and the opposite end face of the fixing ring and the input / output ring In addition to the above, a concave and convex engaging portion in which a part of the engaging portion is engaged and the engaging point is movable is engraved, and is fixed to the opposing surface between the fixing ring and the chuck body by a reaction force generated by tightening a nut ring. The tool chuck is provided with a pressure contact portion.

[0006]

According to the present invention, when the tool is tightened and fixed, no reaction force acts on each chuck claw until the tool is clamped, and the press contact portion between the chuck body and the fixing ring is separated. Each ring is rotated integrally by the rotation of the ring due to the meshing resistance of the bevel gear. When the tool is clamped by tightening and sliding each chuck claw by screw feed of the nut ring, the nut ring is retracted by the reaction force. As a result, the fixing ring is pressed and fixed to the chuck body, so that the torque is increased based on the deceleration action of the torque increasing mechanism.

That is, when the operation ring is rotated,
Since the axis center line of the input / output ring is inclined at a predetermined angle with respect to the axis center line of the chuck body, the engagement portion of the input / output ring rotates while sequentially shifting the engagement point (contact position) with the fixed ring. Further, when the transition of the engagement point of the input / output ring is transmitted to the corresponding portion of the nut ring, the gear engraved on the end face on the opposite side between the input / output ring and the corresponding portion of the nut ring has a difference in the number of teeth. Therefore, the rotation of the corresponding portion of the nut ring is caused by this difference in the number of teeth. Since this rotation is a difference in the number of teeth from one shift of the engagement point of the input / output ring,
Since a large deceleration results in a large torque increase, the nut ring is rotated with this high torque,
The tool is tightened and fixed by feeding each chuck jaw with the rotation of the nut ring.

Next, when releasing the tightening and fixing of the tool, if the operation ring is rotated in the loosening direction, the chuck body and the fixing ring are fixed by pressure contact at the start of the rotation. The corresponding part of the nut ring is rotated by forcibly retracting each chuck claw, and the corresponding part of the nut ring moves forward by the reaction force to release the pressure contact fixing between the chuck body and the fixing ring. Each ring rotates integrally by the rotation operation of
Each chuck pawl is extended and slid by the screw feed of the nut ring to release the tightening and fixing of the tool.

[0009]

According to the present invention, the rotational power of the operating ring is input from the outer peripheral side of the input / output ring, and the power is transmitted via the bevel gear formed on the end face of the input / output ring and the corresponding portion of the nut ring. Since the power is transmitted, the structure and structure of the power transmission path can be simplified as compared with the case where the rotation of the operation ring is reduced by a planetary gear mechanism or the like. Since the bevel gear is carved, the outer diameter of the input / output ring can be reduced, and the torque-up mechanism can be reduced in size.At the same time, the rotation of the operation ring is greatly reduced due to the difference in the number of teeth of the bevel gear. Higher torque is obtained than when the rotational power is directly transmitted to the nut ring, and the tool can be firmly tightened and fixed with a high torque according to the use conditions.

In addition, during the rotation operation until the tool is tightened and fixed and during the rotation operation after the release of the tightening,
Since the pressure fixing between the chuck body and the fixing ring is released, each ring can be rotated integrally, and by rotating the operation ring, a plurality of chuck claws are quickly expanded and contracted to tighten the tool It can be fixed or released and has excellent operability.

Further, the operation ring is rotated in the loosening direction to expand the chuck claws, and even if the chuck claws reach the limit position in the expanding direction, the reaction force of the nut ring separates the press-contact portion from each other. Therefore, it is possible to prevent the fixing ring from rotating idly and to prevent these chuck claws from being fixed at the spreading limit position.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings. The drawing shows a tool chuck used for holding a tool such as a drill bit of an electric drill, and FIG.
In this case, the tool chuck 1 has three guides that penetrate from the outer peripheral surface at the central portion of the chuck body 2 formed into a cylindrical shape to the center surface at the distal end, and gather toward the axial center line of the chuck body 2. Holes 3 are formed, and three chuck claws 4 are inserted into these guide holes 3 so as to be slidable only in the enlargement / reduction direction.

On the outer peripheral surface of the central portion of the chuck body 2, a nut ring 6, which can be divided into an annular notch portion 5 formed by notching a rear end portion of each of the three guide holes 3.
Is split into the split rings 6b, 6b and loosely fitted. Then, the output ring 7 is integrally press-fitted and fixed to the outer peripheral surfaces of the split rings 6b, 6b, and threaded on the inner peripheral surface of the nut ring 6. A female screw 6a is screwed with a male screw 4a threaded on the outer peripheral surface on the base end side of the three chuck claws 4, and the three chucks are rotated by forward and reverse rotation of the nut ring 6. The claws 4 are screwed in the directions of expansion and contraction along the guide holes 3.

On the other hand, an operating ring 8 is rotatably loosely fitted on the outer peripheral surface on the distal end side of the chuck body 2, and the holding ring 12 is rotatably fixed on the outer peripheral surface on the base end side of the chuck main body 2. The circumferential surface of the opposite side between the shaft and the holding ring 12 is rotatably loosely fitted.

Between the nut ring 6 and the operation ring 8, in addition to the output ring 7, an input / output ring 9 loosely fitted on the inner peripheral surface of the central portion of the operation ring 8, and the center of the chuck body 2. A torque-up mechanism 11 composed of a fixing ring 10 loosely fitted on the outer peripheral surface of the motor is interposed.

As shown in FIGS. 2 and 3, a guide groove is formed on the inner peripheral surface of the operation ring 8 about an axis C which is inclined at an angle θ with respect to the axis B of the chuck body 2. , A large number of ball bearings 15 are rotatably held between the guide groove 13 and a guide groove 14 formed on the outer peripheral surface of the input / output ring 9, and the chuck body 2 is formed. The input / output ring 9 is held rotatably in a posture in which the axis center line D of the input / output ring 9 is inclined at an angle θ with respect to the axis center line B of the input / output ring 9. The input / output ring 9 is rotated forward and backward while the center line D is inclined at the angle θ.

A first bevel gear 16 is provided on an end face of the output ring 7 and the input / output ring 9 opposite to each other, while a second bevel gear 16 is provided on an end face of the input / output ring 9 and the fixed ring 10 on the opposite side.
The bevel gear 17 is interposed.

The above-mentioned first bevel gear 16 is composed of a gear 18 formed on the base end face of the output ring 7 and a part of a gear 19 formed on the front end face of the input / output ring 9 opposed thereto. They are meshed. That is, when the operation ring 8 is rotated and the input / output ring 9 is rotated in the forward / reverse direction while maintaining the posture inclined at the angle θ, the gears 18 engraved on the opposite end surfaces of the output ring 7 and the input / output ring 9, Due to the difference in the number of teeth of 19, the rotation of the operation ring 8 is greatly reduced by the number of teeth,
The output of the input / output ring 9 is an output with increased torque.

In the embodiment, the gear 19 formed on the distal end face of the input / output ring 9 is set to 68 teeth, and the gear 18 formed on the base end face of the output ring 7 is set to 66 teeth. ,
Since the difference in the number of teeth between the gears 18 and 19 is set to two, the reduction ratio is 2 (teeth) / 66 (teeth) = 1/33,
A reduction ratio of about 1/33 with respect to the input is obtained.

On the other hand, the above-mentioned second bevel gear 17 is composed of a gear 20 engraved on the proximal end face of the input / output ring 9 and a gear 2 engraved on the distal end face of the fixed ring 10 opposed thereto.
1 and the gears 20, 21
Are set to the same number of teeth, so that the input and the output are equivalent.

Pressing surfaces 22 and 23 are formed on the peripheral surfaces of the chuck body 2 and the fixing ring 10 facing each other, and when the tool A is tightened, the nut ring 6 is retracted by a reaction force generated by the tightening. The pressing surface 22 of the chuck body 2 and the pressing surface 23 of the fixing ring 10 are pressed against each other, and the chuck body 2 and the fixing ring 10 are integrally fixed.

On the inner peripheral surface on the base end side of the operation ring 8 described above,
The spring ring 24 faces the proximal end surface of the fixing ring 10.
And insert the retaining ring 2 behind the spring ring 24.
5 is press-fitted and fixed, and a protruding portion 24 a formed on the inner peripheral edge of the spring ring 24 is engaged with a notch surface 10 a engraved on the proximal end surface of the fixing ring 10. That is,
At the time of rotating the operation ring 8, the notch surface 10 a and the protruding portion 24 a provide an appropriate notch feel by engagement with the protrusion 24 a, and the pressing surface 22 of the chuck body 2 and the pressing surface 23 of the fixed ring 10 are separated from each other. It is urged, and is urged in a direction in which the proximal end surface of the nut ring 6 and the distal end surface of the fixing ring 10 are pressed against each other.

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

First, the tool A is connected to three chuck claws 4.
When the operation ring 8 is rotated in the tightening direction, no reaction force is applied to each of the chuck claws 4. Each ring 6,7,8,9,10 by urging force
Are fixed in the axial direction by pressing, and the pressing surface 22 of the chuck body 2 and the pressing surface 23 of the fixing ring 10 are separated from each other, so that the fixing ring 10 is in a rotatable free state,
By rotating the operation ring 8, each ring 6, 7, 8,
The nut ring 6 is rotated at the same speed as the rotation speed of the operation ring 8, and the three chuck claws 4 are tightened by the fast screw feed of the nut ring 6. To move and hold the tool A.

Next, three chuck claws 4 are attached to the tool A.
Contact, the nut ring 6 and the output ring 7 are retracted by the reaction force, and the press contact surface 22 of the chuck body 2 and the press contact surface 23 of the fixing ring 10 are pressed and fixed. Action occurs.

That is, by rotating the operation ring 8,
When the input / output ring 9 is rotated with the posture inclined at the angle θ, as shown in FIG.
Since the axial center line D of the input / output ring 9 is inclined at a predetermined angle θ, the gear 20 of the second bevel gear 17 engraved on the opposite end face of the input / output ring 9 and the fixed ring 10.
21 sequentially shifts the meshing portion in the circumferential direction, and since the gears 20 and 21 have the same number of teeth, the input / output ring 9
Has no rotation, and shifts the meshing point caused by the inclination sequentially in the rotation direction. The relative movement between the input / output ring 9 and the operation ring 8 is smoothly allowed by the interposition of the ball bearings 15.

On the other hand, the gears 18 of the first bevel gear 16 engraved on the opposite end surfaces of the output ring 7 and the input / output ring 9
On the 19 side, the meshing portion (engaging point) is sequentially shifted in the circumferential direction. However, since the gears 18 and 19 have a difference in the number of teeth of +2 teeth on the gear 19 side, the input / output ring 9 By one rotation of the meshing point, the gear 18 of the output ring 7 is rotated by the insufficient two teeth. As a result, the output ring 7 moves by one rotation of the mesh point of the input / output ring 9,
2/66 (the number of teeth) = 1/33 rotations, and one rotation of the operation ring 8 is reduced to 1/33 rotation of the output ring 7. This large deceleration, that is, an output with increased torque. The nut ring 6 is rotated by the output of the ring 7 to feed the chuck claws 4... By screwing and fixing the tool A with high torque.

Next, when releasing the tightening and fixing of the tool A, when the operation ring 8 is rotated in the loosening direction, the pressure contact surface 22 of the chuck body 2 and the pressure contact surface 23 of the fixing ring 10 at the start of rotation. Are pressed and fixed, the deceleration action of the torque-up mechanism 11 occurs in the initial stage of rotation, rotates the nut ring 6 with a high torque, forcibly retracts the chuck claws 4... 6 and the output ring 7 are advanced, and the fixing ring 10 is advanced by the urging force of the spring ring 24 to separate the press contact surfaces 22 and 23, and the rings 6, 7, 8, 9, 10 are pressed in the axial direction. Since the operation ring 8 is fixed, the rotation of the operation ring 8 causes the rings 6, 7, 8, 9, and 10 to integrally rotate, and the nut ring 6 is rotated at the same speed as the rotation speed of the operation ring 8. , Nut ring 6 screw Each chuck claws Ride three 4 ... extends slides to release the clamping of the tool A.

As described above, the rotational power of the operating ring 8 is input from the outer peripheral side of the input / output ring 9, and the first bevel gear 16 formed on the end face of the nut ring 6 and the input / output ring 9 on the opposite side.
Power is transmitted through the gears 18 and 19, the structure and structure of the power transmission path can be simplified as compared with the case where the rotation of the operation ring 8 is reduced by a planetary gear mechanism or the like, and the nut ring 6 is inserted. Since the gears 18 and 19 of the first bevel gear 16 are engraved on the end face facing the output ring 9, the outer diameter of each ring 7 and 9 can be reduced, so that the entire mechanism can be downsized and the operation ring can be reduced. 8 is greatly reduced by the gears 18 and 19 of the first bevel gear 16, so that a higher torque is obtained than when the rotational power of the operation ring 8 is directly transmitted to the nut ring 6, and a high torque according to the use conditions is obtained. Thus, the tool A can be firmly fixed.

In addition, the pressing and fixing between the chuck body 2 and the fixing ring 10 is released during the rotation operation until the tool A is tightened and fixed and during the rotation operation after the release of the tightening. The rings 6, 7, 8, 9, and 10 can be integrally rotated forward and backward, and the three chuck claws 4 are rapidly expanded and contracted via the nut ring 6 by rotating the operation ring 8. As a result, the tool A can be tightened and fixed or released, and the operability is excellent.

Further, the operation ring 8 is rotated in the loosening direction to expand the chuck claws 4. Even if the chuck claws 4 reach the limit position in the expanding direction, the reaction force of the nut ring 6 does not increase. Acting in the direction in which the press contact surfaces 22 and 23 are separated from each other, it is possible to prevent the fixing ring 10 from rotating idly and the chuck claws 4... From being fixed at the expansion limit position.

In the correspondence between the configuration of the present invention and the above-described embodiment, the corresponding portion of the nut ring of the present invention corresponds to the output ring 7 integrated with the nut ring 6 of the embodiment. The mating portion corresponds to the second bevel gear 17 and the gears 20 and 21, and the press contact portion corresponds to the press contact surfaces 22 and 23. However, the present invention is not limited to the configuration of the above-described embodiment. .

In the above-described embodiment, the speed is reduced by the difference in the number of teeth between the gears 18 and 19 constituting the first bevel gear 16, but the speed is reduced by the second bevel gear 16.
The gears 20 and 21 constituting the bevel gear 17 may be provided with a difference in the number of teeth to reduce the speed.

[Brief description of the drawings]

FIG. 1 is a vertical side view showing an internal structure of a tool chuck.

FIG. 2 is a vertical side view showing an operation ring.

FIG. 3 is a vertical side view showing an input / output ring.

[Explanation of Signs] A: Tool B, C, D: Shaft center line θ: Angle 1: Tool chuck 2: Chuck body 4: Chuck claw 6: Nut ring 7: Output ring 8: Operation ring 9: Input / output ring 10 ... Fixing ring 11 ... Torque-up mechanism 16 ... First bevel gear 18,19 ... Gears 22,23 ... Press contact surface

Claims (1)

(57) [Claims] A plurality of chuck claws are slidably held at the center of the distal end side of the chuck body so as to be able to expand and contract, and the rotational power of an operation ring fitted to the chuck body is transmitted to a nut ring to cause the chuck claws to rotate. A tool chuck that feeds a screw in a direction of expansion and contraction, and a torque-up mechanism that reduces the rotation of the operation ring, increases the torque, and transmits the torque to the nut ring, between the operation ring and the nut ring; A torque-up mechanism is formed by arranging an input / output ring at the center along the axis of the chuck body, a corresponding part of a nut ring at the tip of the chuck, and a fixing ring at the rear end of the chuck. A writing output ring is rotatably held on the inner peripheral surface of the operation ring at a predetermined angle with respect to the axial center line of the chuck body, and a corresponding portion of the input / output ring and the nut ring A gear having a difference in the number of teeth is engraved on the opposite end face of the chuck, and a part of the gears is meshed with each other, and the fixing ring is loosely fitted to an outer peripheral portion of the chuck body. The fixing ring and the input / output ring A concave / convex engaging portion in which a part of each is engaged and the engaging point is movable is engraved on the opposite end surface of the chuck ring, and the reaction force due to the tightening of the nut ring on the opposite surface between the fixing ring and the chuck body. Tool chuck provided with a press-contact part fixed by pressure.