JP4630048B2 - Scroll chuck - Google Patents

Description

  The present invention relates to a scroll chuck for gripping a workpiece used in a machine tool such as a lathe.

  Some machine tools such as a lathe use a scroll chuck that allows a gripping claw to be movable in the radial direction in order to grip the inner and outer periphery of a workpiece to be gripped. In this type of scroll chuck, for example, as shown in Patent Document 1, a plurality of gripping claws arranged in an equal orientation around an axis center on the front surface of the chuck body can move in the radial direction of the chuck body. Is attached. The chuck body includes a scroll member disposed so as to be rotatable about the axis, and a spiral scroll groove is formed on a front surface of the scroll member, and the scroll groove is formed on a rear surface side of the gripping claw. By forming rack teeth that mesh with each other and rotating the scroll member, the gripping claws move in the radial direction so that the workpiece can be gripped.

Since the gripping claw is operated by meshing the scroll groove and the rack teeth, the scroll chuck can easily control the gripping torque, and even a thin and easily deformable workpiece can be gripped with a gentle force without being deformed. Accurate centering can be performed. Further, by increasing the diameter of the scroll member and extending the length of the spiral scroll groove, the distance that the gripping claw can move in the radial direction becomes longer. A large range of the outer diameter or inner diameter can be ensured (see, for example, Patent Document 1 and Patent Document 2).
JP 2000-308909 A JP 2000-308910 A

  On the other hand, there is a chuck device having a face clamp function that operates so as to press a workpiece centered and set by a gripping claw against a reference surface on the front surface of the chuck body. For example, as shown in Patent Document 3, a pulling claw that exhibits a face clamping function is attached to a rod front end that advances and retreats in the axial direction of the chuck body, and each rod is formed in the axial direction on the outer periphery of the rod. Thus, a guide groove having a shape bent in the direction around the axis is formed. A fixed guide pin provided on the chuck body is slidably fitted in the guide groove.

After the workpiece is set in a state where the workpiece is centered by the gripping claws of the chuck body, when the rod is moved backward by operating another drive source, the guide pin slides on the bent portion of the guide groove and moves to the rod. A rotational force is applied, and the pulling claw is moved backward while rotating around the axis, and the pulling claw operates so as to press the work against the front surface (see, for example, Patent Document 3, Patent Document 4, and Patent Document 5).
Japanese Patent Laid-Open No. 2000-706 JP-A-6-328307 Japanese Patent Laid-Open No. 3-190610

  However, when the scroll chuck is provided with a face clamp function, the rod that operates the pulling claw is stationary in the radial direction, so even if the gripping claw moves in the radial direction of the chuck body and grips the workpiece, the pulling claw May not hit the proper gripping position of the workpiece. For this reason, each time a workpiece having a different outer diameter or inner diameter is gripped, the pulling claw must be replaced with one having a size corresponding to the workpiece. Since the replacement work of the pulling claws requires a lot of labor and time, it is not preferable to perform such replacement work.

  Therefore, an object of the present invention is to make it possible to use the face clamp function regardless of the diameter of the workpiece.

  In order to solve the above-mentioned problems, the present invention moves the pulling claw rod in conjunction with the gripping claw. In this way, since the gripping claw of the scroll chuck moves in the radial direction and the pulling claw also moves in the radial direction, the position of the gripping claw, that is, the position of the workpiece, The face clamp function can always be used regardless of the diameter.

  Since the present invention is configured as described above, the face clamp function can be used regardless of the workpiece diameter.

  As a specific embodiment of the above means, in a scroll chuck for gripping a workpiece by moving a plurality of gripping claws provided around the axis of the chuck body in the radial direction of the chuck body, the gripping claws may include the chuck A rod is provided so as to be able to advance and retreat along the axial direction of the main body, and a pulling claw is provided on the rod. It is a thing. In this way, the grip claw of the scroll chuck moves in the radial direction in accordance with the diameter of the workpiece and the rod also moves in the radial direction, so that the grip claw is gripped at any position within the range in which the grip claw can move. The pulling claw moves corresponding to the workpiece, and the face clamp function can always be used.

  In the above configuration, the chuck body is provided with an actuator that is driven by a draw bar so as to be able to advance and retreat in the axial direction of the chuck body, and the actuator is provided with a long hole in the moving direction of the gripping claw. It is possible to adopt a configuration that is guided along the elongated hole and that advances and retracts in the axial direction integrally with the actuator. In this way, when the rod moves in the radial direction along with the movement of the gripping claw, the direction thereof is always maintained the same, and the driving force of the drawbar can be transmitted to the rod via the actuator. The pressure contact force of the pulling claw with respect to the workpiece can be maintained evenly.

  In the above configuration, a configuration in which the orientation of the pulling claw around the axis with respect to the rod can be adjusted may be employed. When the outer diameter or inner diameter of the workpiece to be gripped changes, the orientation of the gripping position of the gripping position by one gripping claw with respect to the workpiece and the workpiece at the press-contact position by the pulling claw that moves in conjunction with the one gripping claw When there is a difference between the azimuths around the axis, the angle formed by both the positions changes depending on the diameter of the workpiece. Therefore, if the orientation of the pulling claw about the axis with respect to the rod can be adjusted, the pressure contact position of the pulling claw with respect to the workpiece can be corrected to the optimum position each time according to the shape of the workpiece.

  As a method for adjusting the orientation of the pulling claw around the axis with respect to the rod, a well-known method can be adopted.For example, the pin is screwed into the pulling claw from both sides with the rod interposed therebetween, It is possible to adopt a configuration in which the rods are in contact with the rods and pressed so as to rotate the rods in opposite directions around the axis. By doing so, the pulling claw is fixed to the rod so as not to move around the axis by the pressure contact of both the pins, and the pressure contact position, that is, the contact position between the pin tip and the rod, By changing around the axis, it is possible to adjust the orientation of the pulling claw around the axis. The change of the pressure contact position can be easily adjusted by changing the screwing degree of the two pins.

  One embodiment will be described with reference to FIGS. In the scroll chuck of this embodiment, as shown in FIG. 2A, on the front surface of the chuck body 1, three gripping claws (top jaws) 2 are arranged at equal positions around the axis, and each gripping claw 2 is arranged. The gripping claw 2 is a scroll chuck that grips the outer periphery of the workpiece W by simultaneously moving in the radial direction.

  As shown in FIG. 3, the chuck body 1 is provided with a scroll flange 5 disposed so as to be rotatable about the axis, and a spiral scroll groove 5a is formed on the front surface of the scroll flange 5. Is forming. A lower claw (master jaw) 3 having rack teeth 3a meshing with the scroll groove 5a is disposed on the front surface of the scroll flange 5, as shown in the figure, and a bolt 2c is further provided on the front surface of the lower claw 3. The gripping claw 2 is attached via. Further, a carbide tip 2a is attached to the front inner end of the gripping claw 2 via a bolt 2d.

  A radial groove 5b is formed on the rear surface side of the scroll flange 5, and the groove 5b is inserted in the radial direction from the outside of the chuck body 1 toward the axis as shown in FIG. The grooves 5b and 6b mesh with the groove 6b on the circumferential surface of the shaft 6 to constitute a bevel gear. The pinion shaft 6 is disposed on the front surface of the base 7 of the chuck body 1 and is fixed to the base 7 together with the scroll flange 5 by a fixing member 4 shown in the drawing. By rotating the pinion shaft 6 around the axis, the scroll flange 5 rotates around the axis of the chuck body 1 via both grooves 5b, 6b, and the rotation causes the scroll groove 5a and the rack teeth 3a to slide. The grip claw 2 moves in the radial direction together with the lower claw 3 by moving.

  The grip claw 2 is provided with a pull claw (face clamp jaw) 12 that exhibits a face clamp function. As shown in FIG. 4, the pulling pawl 12 is configured such that a draw bar 8 that is driven to advance and retreat in the axial direction is provided at the axial center of the chuck body 1, and an actuator 10 is connected to the draw bar 8. The drawbar 8 and the chuck body 1 are driven so as to advance and retreat in the axial direction. The actuator 10 is provided with an actuator flange 10a that extends radially outward at the front end and extends to the side of the gripping claw 2. The tip of the actuator flange 10a is parallel to the moving direction of the gripping claw 2. A long hole 13 is provided, and the end of the long groove 13 opens outward as shown in FIG.

  A rod 11 parallel to the axial direction of the chuck body 1 is accommodated in the elongated hole 13, and the rod 11 is provided on the side protrusion 2 ′ of the gripping claw 2 as shown in FIG. 1. Through the hole 2b and fixed to the grip claw 2 so as to be immovable in the radial direction, and is held rotatably about the axis via the bearing 16, and can be moved back and forth in the axial direction with respect to the grip claw 2. Supported. Further, the front end side of the rod 11 protrudes further forward than the penetrating portion of the gripping claw 2, and a pulling claw 12 is provided at the front end.

  As shown in FIGS. 1 and 6, the pulling claw 12 and the rod 11 are connected by fitting the insertion hole 12 b of the pulling claw 12 to the front end of the rod 11 and attaching the rod 11 to the pulling claw 12. In a state where the pins 22 and 22 are screwed in from both the upper and lower sides and are screwed in a predetermined amount and pressed against the rod 11, the pins 22 and 22 are fixed to the pulling claws 12 with nuts 22b and 22b. Both pins 22 and 22 abut against the recesses 11a and 11a of the rod 11 and press the rod 11 so as to rotate in the opposite direction around the axis. Therefore, the screwing amounts of the pins 22 and 22 are mutually adjusted. By doing so, the contact position (direction of the contact position) between the tips 22a and 22a of the pins 22 and 22 and the recesses 11a and 11a of the rod 11 can be adjusted around the axis of the rod 11. By this adjustment, the pulling claw 12 can adjust the orientation around the axis with respect to the rod 11.

  Further, as shown in FIGS. 1 and 4, the rear end side of the rod 11 has an enlarged diameter before and after the elongated hole 13, and the enlarged stepped portions 11b and 11b are arranged at the front and rear of the actuator flange 10a. It abuts against both end faces 10b, 10b and is fixed to the actuator 10 in the axial direction. For this reason, the rod 11 advances and retreats in the axial direction integrally with the actuator 10 and is held by the actuator flange 10a so as to be rotatable about the axis.

  Further, as shown in FIG. 5B, a guide groove 14 is formed on the peripheral surface of the rod 11. The guide groove 14 is formed in the axial direction and bent in the axial direction. As shown in FIG. 4, a fixed guide pin 15 screwed into the grip claw 2 is slidably fitted into the guide groove 14.

  Since the function of a general scroll chuck is the same as that of the conventional example, the description thereof will be omitted, and the operation of the face clamp function will be described. As shown by an arrow P in FIG. By rotating the scroll flange, as indicated by an arrow Q in FIG. 2A, the gripping claw 2 moves in the radial direction, and the tip 2a grips the outer periphery of the workpiece W from three directions. In this state, the axis of the workpiece W is set in a state of being aligned with the axis of the chuck body 1.

  At this time, since the rod 11 is fixed in the radial direction relative to the gripping claw 2, if the gripping claw 2 moves in the radial direction when gripping the workpiece W, the rod 11 is moved to the gripping claw 2. And move along the moving direction of the gripping claws 2. During the movement, the rod 11 slides on the inner wall of the long hole 13, so that the rod 11 is guided along the length direction of the long hole 13, and the direction of the rod 11 depends on the axis of the chuck body 1. Kept in parallel.

  In this state, when the drive source is operated to retract the draw bar 8, the actuator 10 and the rod 11 are retracted in the axial direction to the left shown in FIG. When the rod 11 is retracted, the guide pin 15 slides on the bent portion of the guide groove 14 to apply a rotational force to the rod 11, and the pulling claw 12 is moved from the position indicated by the chain line in FIGS. While rotating around the axis to the position indicated by the solid line, the tip 12a of the pulling claw 12 operates so as to press the workpiece W against the front surface. By this pressure contact, the workpiece W is attracted to the front surface of the chuck body 1 and set firmly. At this time, since the three rods 11 are always maintained in parallel with the axis of the chuck body 1, transmission of the driving force to the pulling claws 12 is maintained evenly.

  At the time of this face clamp, the orientation of the pulling claw 12 about the axis of the rod 11 can be adjusted by operating the pins 22 and 22 screwed into the pulling claw 12, so that the screwing amount of the pins 22 and 22 is increased. Is adjusted so that the orientation of the tip 12a of the pulling claw 12 is adjusted so that the work W to be gripped is pressed to the optimum position as shown in FIG. This is because, when the outer diameter of the workpiece W to be gripped changes, the orientation around the workpiece W axis center of the gripping position by the one gripping claw 2 with respect to the workpiece W and the pulling that moves in conjunction with the one gripping claw 2. The angle (angle α shown in FIG. 2A) formed by the azimuth around the workpiece W axis center of the pressure contact position by the claw 12 changes depending on the diameter of the workpiece W. Therefore, the pressure contact position of the pulling claw 12 with respect to the workpiece W is corrected to an optimum position by finely adjusting the azimuth around the axis of the pulling claw 12 with respect to the rod 11 in accordance with the change in the angle α. .

  After the gripped workpiece W is processed, when the workpiece W is released from the chuck body 1, the drive source is operated to advance the draw bar 8, and the actuator 10 and the rod 11 are integrated with the draw bar 8. 4 advances in the axial direction to the right as shown in FIG. When the rod 11 moves forward, the pulling claw 12 moves in the direction opposite to that when the rod 11 moves backward, and the pressure contact of the front surface of the workpiece W by the tip 12a of the pulling claw 12 is released.

  In this embodiment, a pulling claw 12 that exhibits a face clamping function, and a rod 11 that supports the pulling claw 12 so as to be able to advance and retreat are provided in a gripping claw 2 of a scroll chuck, and the draw bar provided in the chuck body 1. However, the present invention is not limited to this embodiment, and the rod 11 and the pulling claw 12 are provided so as to be able to advance and retract in the axial direction with respect to the gripping claw 2, and the rod 11 has a diameter of the gripping claw 2. The rod 11 may be moved back and forth by another known driving method as long as it moves in the moving direction along with the direction movement. For example, a drive source for moving the rod 11 back and forth in the axial direction may be provided so as to move in the radial direction together with the gripping claws 2. At the same time, a known power transmission means may be provided to continuously transmit the driving force from the driving source to the rod 11 even when moving in the radial direction so that the rod 11 can always advance and retreat in the axial direction. In addition, the gripping claws 2 may grip the outer periphery of the workpiece W as in this embodiment. In particular, when the face clamping function is required, the gripping claws 2 are not attached to the workpiece W. The inner periphery may be gripped.

The principal part expansion perspective view of one Example (A) is a front view of the same embodiment, (b) is a bottom view. Sectional side view showing the III-III cross section of FIG. Cut-away side view showing section IV-IV in Fig. 2 (a) It is the principal part enlarged view of the Example, (a) is a front view of a holding nail, (b) is the bottom view. Enlarged view of the main part showing the connection between the pulling claw and the rod

Explanation of symbols

1 Chuck body 2 Grip claw (top jaw)
2a Tip 3 Lower jaw (master jaw)
3a Rack teeth 4 Fixing member 5 Scroll flanges 5a, 5b, 6b Groove 6 Pinion 7 Base 8 Drawbar 9 Fixing bolt 10 Actuator 10a Actuator flange 11 Rod 11a Recess 12 Pulling claw (face clamp jaw)
12a Tip 13 Long hole 14 Guide groove 15 Fixing pin 16 Bearing 21 Fixing bolt 22 Pin W Workpiece

Claims (1)

In the scroll chuck for gripping the workpiece W by moving a plurality of gripping claws 2 provided around the axis of the chuck body 1 in the radial direction of the chuck body 1,
A rod 11 is provided on the gripping claw 2 so as to be movable back and forth in the axial direction of the chuck body 1, and a pulling claw 12 is provided on the rod 11. , Pressed against the front surface of the workpiece W gripped by the gripping claws 2 ,
The pulling pawl 12, Ri adjustable der axis around bearing for the rod 11, the pulling pawl 12, threaded pins 22, 22 from both sides by interposing the rod 11, the two pins 22, 22, scroll chuck you wherein each in contact with the rod 11 pushes to rotate the rod 11 in the axial around opposite direction.

Images