JP6374284B2 - Chuck device with workpiece holding guide - Google Patents

Description

  The present invention relates to a chuck device with a workpiece holding guide that has a workpiece holding guide in a chuck portion and retracts the workpiece holding guide in conjunction with a gripping operation by a chuck claw.

  In a machine tool or the like, a chuck is used as a configuration for setting a workpiece to be processed. It is necessary for an operator to place the workpiece at a clampable position with respect to the chuck. However, if the operator himself / herself holds it until the workpiece is clamped, there is a risk that the chuck may get caught.Therefore, a workpiece holding guide for holding the workpiece must be provided on the chuck portion. There is. In this method, the workpiece is positioned at the clamp position, and is retracted after the workpiece is gripped by the chuck claw so as not to hinder the processing.

  For example, in a machine tool that performs inner diameter processing, a workpiece holding guide is disposed at the center of a plurality of chuck claws, and a ring-shaped workpiece is attached to the workpiece holding guide so as to be inserted into the inner diameter portion. The workpiece placed in the processing section is positioned by being pressed against the seating surface by the pusher, and is gripped by the chuck claw by driving the chuck device. Thereafter, inner diameter processing is performed on the inner peripheral surface of the workpiece, but the workpiece holding guide located in the workpiece becomes an obstacle. Therefore, the work holding guide moves to the retracted position so as to be detached from the work.

JP 2002-254221 A

  In the chuck device provided with the workpiece holding guide, two operations are performed: holding the workpiece by the chuck claws and retracting the workpiece holding guide from the workpiece. Therefore, two actuators (such as an air cylinder) that perform each operation are necessary. However, this not only complicates the structure of the chuck device, but also increases the number of parts. Further, not only labor and time are required for manufacturing the chuck device, but also labor and time are similarly required for maintenance. In addition, such a chuck device is complicated and has a large number of parts, which increases the manufacturing cost and the part cost.

  In this regard, for example, in Patent Document 1 described above, the movement in the radial direction for disconnecting the work / tool holder from the clamping head and the movement in the axial direction for disconnecting the clamping member are as follows: A chuck device is disclosed that uses a cotter and is executed by the output of one cylinder. However, the conventional example described in this document only realizes movement in two directions, and a time difference such as retraction of the workpiece chuck and the workpiece holding guide is required like a chuck device having a workpiece holding guide. It cannot cope with different operations.

  Therefore, in order to solve such a problem, the present invention has an object to provide a chuck device with a work holding guide that allows a workpiece to be gripped by a chuck claw and a work holding guide to be retracted from the work with a single telescopic actuator. And

  A chuck device with a workpiece holding guide according to the present invention includes a plurality of chuck claws for gripping a workpiece disposed at a central portion from the outside and a driving force acting in a direction parallel to a central axis passing through the central portion. A chuck opening and closing mechanism that opens and closes, a telescopic actuator that outputs the driving force by expansion and contraction, and a work holding guide that is fixed to a guide rod that is movable in the axial direction of the central axis and is positioned in the central portion, The guide rod is connected to an output shaft of the telescopic actuator, and the work holding guide is movable between a holding position and a retracted position by the expansion and contraction of the telescopic actuator, and the chuck opening and closing mechanism and the guide rod are The output of the telescopic actuator acting in the retracting direction of the workpiece holding guide is the workpiece holding guide. There after moving to the retracted position, in which the chuck jaws are coupled to transmit a gripping force for gripping the workpiece.

  According to the present invention, the chuck pawl grips the workpiece after the output of the telescopic actuator acting in the retracting direction of the workpiece holding guide moves between the chuck opening / closing mechanism and the guide rod and the workpiece holding guide moves to the retracted position. Since it is configured to transmit the gripping force, the movement of the workpiece holding guide and the gripping / release of the workpiece by the chuck pawl can be executed by one telescopic actuator.

It is sectional drawing which shows the principal part of embodiment of the chuck apparatus with a workpiece | work holding guide. It is the front view which showed the chuck | zipper opening / closing mechanism seeing in the XL direction of FIG. FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2 showing the chuck opening / closing mechanism in an unclamped state. It is sectional drawing which showed the chuck | zipper opening / closing mechanism of a temporary clamp state. It is sectional drawing which showed the chuck | zipper opening / closing mechanism of the clamped state.

  Next, an embodiment of a chuck device with a workpiece holding guide according to the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a main part of a chuck device with a workpiece holding guide. This chuck device 1 with a work holding guide constitutes a spindle chuck of a machine tool. In the machine tool, a rotational motion is given to the workpiece W gripped by the spindle chuck, and cutting is performed by a cutting tool. In particular, in the present embodiment, the inner diameter machining of the ring-shaped workpiece W is performed.

  In such a machine tool, the workpiece holding guide 36 is configured to place the workpiece W at a clamping position where the workpiece W is gripped by the chuck claws 32 prior to the inner diameter processing. In the present embodiment, a chuck device with a work holding guide constituting the spindle chuck of a machine tool will be described. Note that the chuck device with the work holding guide can be applied to machine tools other than those described in the present embodiment, or other processing machines other than the machine tools, as long as the effect is obtained.

  A chuck device with a workpiece holding guide (hereinafter, simply referred to as “chuck device”) 1 shown in FIG. 1 has a spindle 12 rotatably assembled in a cylindrical spindle stock 11. A chuck opening / closing mechanism 13 is attached to the spindle 12 at the front end on the right side (XR direction) of the drawing, and a telescopic actuator for driving the chuck opening / closing mechanism 13 is provided on the opposite side (XL direction). In this embodiment, the air cylinder (chuck cylinder) 14 is used for the telescopic actuator, but an electric cylinder or the like may be used.

  A pulley 15 is fixed to the spindle 12, and a timing belt 16 is stretched between a pulley fixed to a rotating shaft of a servo motor (not shown). A rotation output of the servo motor is transmitted to the chuck opening / closing mechanism so that the gripped workpiece W is rotated. The spindle 12 is provided with an encoder (not shown) for detecting the rotational speed. Therefore, the timing belt 18 is also stretched between the pulley 17 fixed to the spindle 12 and the pulley on the encoder side.

  The chuck cylinder 14 is a double rod type air cylinder. When compressed air is supplied and discharged through the inducer 21, the operating rods 141 and 142 advance and retract in the axial direction (XR direction, XL direction). The operating rod 141 integrated with the piston 143 is connected to the chuck opening / closing mechanism 13 side, and the inducer 22 is fixed to the other operating rod 142. Compressed air is also supplied from the inducer 22. This compressed air is sent to the chuck opening / closing mechanism 13 and used for detecting the seating of the workpiece W pressed against the washer 37.

  The operating rods 141 and 142 are provided with through holes 145 in the axial direction. A joint rod 25 and a guide rod 26 are coaxially connected to the operating rod 141, and a through hole 251 is also drilled in the joint rod 25 in the axial direction. The guide rod 26 is formed with a shaft hole 261 and a lateral hole 262 communicating with the through hole 251 of the joint rod 25, and compressed air is fed into an air flow path 373 formed in the washer 37. . The back pressure of the sent compressed air is detected by the pressure switch, and it is confirmed whether or not the workpiece W is properly seated.

  2 is a front view showing the chuck opening / closing mechanism 13 as viewed in the XL direction of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2 showing the chuck opening / closing mechanism 13 in an unclamped state. FIG. The chuck opening / closing mechanism 13 has a rotatable main shaft 31, and the main shaft 31 is fixed to the end of the spindle 12 (see FIG. 1). The main shaft 31 is formed with a retractable pin arbor chuck. In the pin arbor chuck, three chuck claws 32 arranged on the same circumference are respectively attached to the tip end portions of the pin arbor 33, and the pin arbor 33 performs an inclination movement of a predetermined angle with respect to the center axis O, whereby the workpiece W Is gripped while being brought into close contact with the washer 37.

  More specifically, the main shaft 31 is a cylindrical block, a guide hole having a tapered curved sliding contact surface 311 is formed, and the pin arbor 33 is fitted in a slidable state. The pin arbor 33 is inclined so that the opposite drive transmission side end 331 side is closer to the central axis O than the chuck claw 32 side. The drive transmission block 35 is coupled to the drive transmission side end 331 so that a driving force in a direction parallel to the central axis O acts on the pin arbor 33.

  The drive transmission block 35 is a cylindrical member, is formed such that the projection 351 protrudes in the radial direction, and is inserted into an inner diameter side recess 332 formed at the drive transmission side end 331 of each pin arbor 33. Accordingly, by moving the drive transmission block 35 in the axial direction, the three pin arbors 33 slide simultaneously in the oblique direction, and the three chuck claws 32 are opened and closed. At this time, if the movement of the drive transmission block 35 is the left side of FIG. 3 (XL direction), the chuck claw 32 is closed and the workpiece W is clamped, and if the movement of the drive transmission block 35 is the right side of FIG. Is opened to release the workpiece W.

  The drive source for gripping and releasing the workpiece W is the chuck cylinder 14, and its expansion / contraction operation is transmitted to the drive transmission block 35 via the guide rod 26. However, in this embodiment, the operation of the guide rod 26 is not directly connected to the drive transmission block 35. This is because it is necessary to provide a time difference between two different operations of gripping the workpiece W and retracting the workpiece holding guide 36. The work holding guide 36 is fixed to the tip of the guide rod 26 and is located at the center of the three chuck claws 32. The shape is a disk shape that matches the ring-shaped workpiece W.

  In processing, the workpiece W is attached to the workpiece holding guide 36 by the operator as shown in FIG. Thereafter, the inner peripheral surface of the workpiece W gripped by the chuck claws 32 is processed to have an inner diameter. However, if the workpiece holding guide 36 is contained therein, the processing is obstructed. Therefore, after the workpiece W is clamped, the workpiece holding guide 36 needs to be detached from the workpiece W. Thus, the washer 37 is provided with a retreating place for such a work holding guide 36. The washer 37 is provided with three arc-shaped receiving portions 371 for receiving the workpiece W at three positions corresponding to the pin arbor 33, and the interior surrounded by the receiving portions 371 serves as a retreat space for the workpiece holding guide 36. The work holding guide 36 is a holding position where the position shown in FIG. 3 holds the work W, and the position shown in FIG. 5 is a retracted position moved so as not to affect the processing of the work W.

  The movement of the work holding guide 36 is executed by moving the supported guide rod 26 in the axial direction. In the present embodiment, the guide rod 26 has a function of transmitting a driving force for opening and closing the chuck pawl 32 in addition to moving the work holding guide 36 to each position. However, if these two functions act simultaneously, the guide rod 26 cannot be moved in the XL direction by the clamp of the workpiece W, and the retraction of the workpiece holding guide 36 is restricted in the middle. Therefore, the chuck opening / closing mechanism 13 of the present embodiment is configured such that a time difference is generated between the retraction of the work holding guide 36 and the clamping of the work W by the chuck claws 32.

  In order to provide a time difference, the drive transmission block 35 is formed with an engagement recess 352 having an enlarged inner diameter, and the guide rod 26 is formed with an engagement protrusion 263 projecting in the radial direction to enter the engagement recess 352. . The engagement protrusion 263 can move in the XL direction in the engagement recess 352 until it abuts against the axial wall surface 355, and drive force is transmitted through the guide rod 26 while moving in the non-engagement portion. Not transmitted to block 35. An abutting ring 38 is fixed to the guide rod 26 and is disposed on the opposite side of the engaging protrusion 263 so as to abut against the drive transmission block 35 in the XR direction. Therefore, power transmission from the guide rod 26 to the drive transmission block 35 is performed via the engagement protrusion 263 in the XL direction and via the abutment ring 38 in the XR direction.

  Since the drive transmission block 35 is free to move between the engagement protrusion 263 and the abutting ring 38, rattling may occur when one of them is not pressed. Therefore, a spring 39 is loaded between the drive transmission block 35 and the washer 37. The drive transmission block 35 is always urged in the XL direction by a spring 39, and is pressed against the abutment ring 38 during unclamping shown in FIG. By adjusting the position of the abutment ring 38, not only the drive transmission block 35 butted against the abutment ring 38, the positions of the pin arbor 33 and the chuck pawl 32 can be adjusted. Therefore, the chuck opening / closing mechanism 13 can adjust the position of the chuck claw 32 with respect to the central axis O during unclamping by adjusting the position of the abutting ring 38, that is, the opening degree of the chuck.

  Next, the operation of the chuck device 1 will be described. First, as shown in FIGS. 1 and 3, the work W is attached to the work holding guide 36 by the operator. At this time, the chuck cylinder 14 extends in the XR direction as shown in FIG. 1, and the work holding guide 36 is disposed at the holding position. Further, due to the output of the chuck cylinder 14, the drive transmission block 35 is pushed and moved in the XR direction via the abutting ring 38, and the chuck pawl 32 is in an unclamped state. In the machine tool, the workpiece W is pressed against the seating surface (reference surface) of the washer 37 in the XL direction by a pusher (not shown).

  Then, the chuck cylinder 14 is expanded and contracted in the XL direction, and the state of the chuck opening / closing mechanism 13 changes as shown in FIGS. First, the chuck claw 32 is abutted against the workpiece W while the abutting ring 38 moves in the XL direction to the position shown in FIG. That is, the drive transmission block 35 is moved in the XL direction by the urging force of the spring 39, and the pin arbor 33 is pulled in the same direction to slide obliquely on the sliding contact surface 311 of the main shaft 31. At this time point, the output of the chuck cylinder 14 does not act on the chuck pawl 32 because the engagement protrusion 263 does not contact the axial wall surface 355 in the XL direction forming the engagement recess 352. In addition, since the guide rod 26 can move in the XL direction, the work holding guide 36 can further move away from the work W to the retreat space in the receiving portion 371.

  At this time, the chuck claws 32 are in a temporarily clamped state in which the workpiece W is gripped, but a gripping force that keeps the workpiece W firmly seated is not acting. This is because, as described above, the spring 39 has only a spring force that prevents the drive transmission block 35 from rattling. Incidentally, at the stage shown in FIG. 4, the workpiece W is still pressed against the washer 37 by a pusher (not shown). Therefore, even if the work holding guide 36 is detached, the sitting state of the work W is maintained. However, since this is a case of a machine tool having a pusher, when the pusher does not exist, the seating state of the workpiece W can be maintained by using the spring 39 having a large spring force. Good.

  When the abutting ring 38 moves in the XL direction to the position shown in FIG. 5, the engagement protrusion 263 hits the axial wall surface 355 in the XL direction of the engagement recess 352, and the output of the chuck cylinder 14 passes through the guide rod 26. To the drive transmission block 35. When a driving force acts on the drive transmission block 35 in the XL direction, an oblique force toward the central axis O acts on the chuck claw 32 via the pin arbor 33, and the workpiece W is pulled and gripped. In this way, the workpiece W is brought into close contact with the seating surface of the washer 37, and a stable clamp state without lifting is obtained.

  The guide rod 26 that has hit the axial wall surface 355 of the engaging recess 352 cannot move further in the XL direction. However, at this stage, the work holding guide 36 has already come off the work W, and the inside of the receiving part 371 It has moved to a certain retreat position. Therefore, the workpiece W can be machined inside. Note that the retracted position of the work holding guide 36 does not have to be a hindrance in the subsequent inner diameter processing, and therefore does not need to be a position completely disengaged from the work W in some cases.

  Thereafter, the spindle 12 is rotated by driving a servo motor (not shown), and the spindle 31 rotates. In the chuck opening / closing mechanism 13, the pin arbor 33, the washer 27, and the work W rotate along with the main shaft 31. Then, turning with the cutting tool applied to the inner peripheral surface is performed on the rotating workpiece W. After turning, the chuck cylinder 14 expands and contracts in the XR direction, and the chuck opening / closing mechanism 13 changes from the state shown in FIG. 5 to FIGS. 4 and 3. That is, the drive transmission block 35 is moved by being pushed by the abutting ring 38, and the chuck claw 32 is in an unclamped state in which the workpiece W is released. The workpiece holding guide 36 moves to the holding position that has entered the workpiece W, and the operator removes the workpiece W.

  Therefore, according to the present embodiment, the movement of the workpiece holding guide 36 and the gripping and releasing of the workpiece W by the chuck claws 32 can be performed by one chuck cylinder 14. Therefore, the chuck device 1 can be reduced in size, and the installation space when mounted on a machine tool or the like can be reduced. In addition, since the driving means has a simple structure including only the chuck cylinder 14, the cost can be reduced, and the manufacturing and maintenance can be facilitated as compared with the prior art, and the cost can also be reduced in that respect. .

  In the present embodiment, in particular, a time difference is generated between the retraction of the work holding guide 36 and the work gripping by the chuck claws 32. The configuration for providing the time difference is also a simple configuration such as the engagement recess 352 of the drive transmission block 35 and the engagement protrusion 263 of the guide rod 26, so that the chuck device 1 that exhibits the above effects can be provided at low cost. it can. In the chuck opening / closing mechanism 13, the movement of the drive transmission block 35 in the XL direction is restricted by the abutting ring 38, but the fixing position of the abutting ring 38 is adjusted in the axial direction with respect to the guide rod 26. Thus, the position adjustment of the chuck claw 32 at the time of unclamping can be easily performed. That is, it is possible to easily correspond to the shape and size of the workpiece W.

As mentioned above, although embodiment of the chuck apparatus with a workpiece | work holding guide of this invention was described, this invention is not limited to this, A various change is possible in the range which does not deviate from the meaning.
For example, in the above-described embodiment, the pin arbor chuck constituted by the pin arbor moving in the tilt direction is shown as the chuck opening / closing mechanism, but the linear driving force of the telescopic actuator is converted into the operation of the chuck claw moving in the radial direction. Any configuration may be used.

  Specifically, a configuration in which a swingable chuck member including a chuck claw is swung by expansion and contraction of a telescopic actuator via a cam or the like can be considered. In that case, the expansion / contraction of the expansion / contraction actuator and the swing of the chuck member may be connected so as to have a time difference so that clamping can be performed after the workpiece holding guide is retracted. That is, at the connecting portion, an engagement recess is formed on the chuck member side, and the cam swings the chuck member after the work holding guide is retracted.

Further, the retracted position of the workpiece holding member is to move the workpiece holding member to a predetermined position so that it can be processed. Therefore, in the above-described embodiment, as shown in FIG. 5, the workpiece is completely detached from the workpiece W. However, as long as machining is possible, the workpiece holding guide 36 may be located in the workpiece. .
Further, the guide rod connects the telescopic actuator and the work holding member, and therefore, for example, the joint rod 25 of the above embodiment does not deviate from the concept of the guide rod.
Moreover, although the said embodiment demonstrated the case where the internal diameter process of a ring-shaped workpiece | work was performed, you may perform the outer diameter process of a cylindrical shaped workpiece | work. In that case, the workpiece holding guide is retracted so as not to rotate integrally with the workpiece during processing.

DESCRIPTION OF SYMBOLS 1 ... Chuck apparatus with a workpiece holding guide 12 ... Spindle 13 ... Chuck opening / closing mechanism 14 ... Chuck cylinder 26 ... Guide rod 31 ... Main shaft 32 ... Chuck claw 33 ... Pin arbor 35 ... Drive transmission block 36 ... Work holding guide 37 ... Washer 38 ... Projection This ring 39 ... Spring

Claims (5)

A plurality of chuck claws for gripping the workpiece arranged in the central portion from the outside;
A chuck opening and closing mechanism for opening and closing the chuck pawl by a driving force acting in a direction parallel to a central axis penetrating the central portion;
A telescopic actuator that outputs the driving force by expansion and contraction;
A work holding guide fixed to a guide rod movable in the axial direction of the central axis and positioned at the central portion;
The guide rod is connected to an output shaft of the telescopic actuator, and the work holding guide is movable between a holding position and a retracted position by the expansion and contraction of the expansion actuator.
The chuck opening / closing mechanism and the guide rod hold the workpiece by the chuck pawl after the output of the telescopic actuator acting in the retracting direction of the workpiece holding guide moves to the retracted position. A chuck device with a work holding guide, which is connected so as to transmit as a gripping force. The guide rod is formed with an engaging protrusion protruding in the radial direction, and the chuck opening / closing mechanism is formed with an engaging recess for entering the engaging protrusion,
The engaging recess has a space in which the engaging protrusion can move in the retracting direction of the workpiece holding guide, and the chuck opening / closing mechanism has an output of the telescopic actuator for gripping the workpiece at the retracted position. 2. The chuck device with a workpiece holding guide according to claim 1, wherein the chuck device is transmitted from the engagement protrusion applied to a wall surface forming the engagement recess.   The restriction member for restricting the operation on the grip side of the chuck opening / closing mechanism is fixed to the guide rod so that the position in the axial direction can be adjusted. The chuck device with a workpiece holding guide according to 1.   The chuck opening / closing mechanism includes a drive transmission block that is penetrated by the guide rod and arranged to be movable in the axial direction, and the drive transmission block abuts the regulating member in a holding side direction of the work holding guide, 4. The chuck device with a work holding guide according to claim 3, wherein the chuck device is biased by a spring member in a retracting direction from the opposite side. The chuck device with a work holding guide according to claim 4, wherein the spring member gives a gripping force for temporarily gripping the work to the chuck pawl.

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