JP5644448B2 - Chuck device - Google Patents

Description

  The present invention relates to a chuck device for gripping a workpiece provided in a loader device or the like for supplying and discharging a workpiece to and from a machine tool.

  The chuck device provided in the loader device or the like includes an open / close type chuck claw for gripping the workpiece, and the workpiece is moved along the central axis from the workpiece gripping position by the chuck claw when passing the workpiece to a machine tool or another device. Pusher to push out. Conventionally, this pusher push-out operation has been performed by the elastic repulsion of a spring (for example, Patent Document 1). Other than the configuration using a spring, a configuration using a fluid pressure cylinder has also been proposed (for example, Patent Document 2).

JP 2006-7378 A JP 2010-5766 Gazette

  The fluid pressure cylinder using the spring presses the work against the pusher when the chuck pawl is holding the work so that the pusher can push out the work when the chuck pawl releases the work. Therefore, the force that pushes back the workpiece by the pusher acts on the chuck claw, and it is necessary to increase the gripping force of the chuck claw accordingly.

  In the configuration described in Patent Document 1, the chuck claw is closed and the workpiece is gripped by changing the position of the base end of the spring between when the chuck claw is closed and when the chuck claw is open. However, the biasing force of the spring acting on the pusher is reduced. However, the urging force of the spring is acting on the pusher while the chuck claw is gripping the workpiece, and the gripping force of the chuck claw that is not lost is still necessary.

  Moreover, the fluid pressure cylinder using a spring has a problem that the effective stroke of the pusher is short due to the nature of the spring. This is because the elastic repulsive force of the spring changes depending on the length of expansion and contraction, and thus the range in which the elastic repulsive force suitable for pushing out the workpiece can be obtained is narrow. If the effective stroke of the pusher is short, the chuck pawl or pusher needs to be replaced whenever the axial length or shape of the workpiece changes.

For example, as shown in FIG. 9, when the workpiece W _L having a long axial length (FIG. 9A) is changed to the short workpiece W _S (FIG. 9B), the pusher 3 having a short effective stroke is changed to the workpiece W. _S will not reach. In this case, the chuck pawl 2 is replaced with one having a short axial portion (FIG. (C)), or an adjustment block 50 for adjusting the axial position of the work pressing surface is attached to the pusher 3 (same as above). Figure (D)).

  Further, as shown in FIG. 10, the pusher 3 for the stepped workpiece W composed of the large diameter portion Wa and the small diameter portion Wb pushes the large diameter portion Wa side of the workpiece W (FIG. 10A). 51 and a central pushing portion 52 that pushes the small diameter portion Wb side ((B) in the figure), and is configured so as to be able to cope even if the stepped workpiece W is reversed. However, for the stepped workpiece W in which the small-diameter portion Wb has a long axial length, the large-diameter portion Wa can be gripped by the chuck claw 2 from the large-diameter portion Wa side. From the Wb side, the small-diameter portion Wb is in the way, and the large-diameter portion Wa cannot be gripped by the chuck claw 2 ((D) in the figure). Therefore, when gripping the large-diameter portion Wa from the large-diameter portion Wa side with the chuck claw 2, the chuck claw 2 must be replaced with one having a long axial portion (not shown).

  When the work push-out operation of the pusher 3 is performed by the fluid pressure cylinder, the pusher 3 does not push the work W while the chuck claw 2 is holding the work W, so that the gripping force of the chuck claw 2 can be reduced. . In general, since the stroke of the pusher 3 can be made longer, the number of times the chuck pawl 2 and the pusher 3 are changed by changing the type of the workpiece W can be reduced. However, since the fluid pressure cylinder using the conventional fluid pressure cylinder described in Patent Document 2 is arranged side by side with the chuck claw opening / closing mechanism, the size of the entire chuck device is increased. Therefore, it is difficult to use a fluid pressure cylinder of a long stroke type.

SUMMARY OF THE INVENTION An object of the present invention is to provide a chuck device that can take a long stroke of the pusher without pushing the work when the chuck claw is holding the work and has a compact configuration.
Another object of the present invention is to compactly arrange a chuck pawl opening / closing mechanism and a pusher pushing fluid pressure cylinder.
Still another object of the present invention is to provide a more compact arrangement of the chuck claw opening / closing mechanism and the pusher pushing fluid pressure cylinder, and to reliably open and close the chuck claw by the chuck claw opening / closing mechanism.

  The chuck device of the present invention is arranged radially on the outer periphery of the central shaft, each of which has a plurality of chuck claws that open and close in the radial direction to grip the workpiece, a chuck claw opening / closing mechanism that opens and closes each chuck claw, and the workpiece. A pusher that pushes in a direction along the central axis from a position gripped by the chuck claw, and a fluid pressure cylinder that causes the pusher to push the workpiece, and the fluid pressure cylinder and the chuck claw opening / closing mechanism are They were arranged side by side in the orthogonal direction.

  According to this configuration, since the fluid pressure cylinder is used for pushing out the pusher, it can be designed so that the pusher does not push the work while the chuck claw is holding the work. Therefore, the gripping force of the chuck claw can be reduced. In addition, since the fluid pressure cylinder is used, the pusher stroke can be increased, and the number of times the chuck pawl or pusher is changed due to the change of the workpiece can be reduced. Furthermore, by arranging the fluid pressure cylinder and the chuck claw opening / closing mechanism side by side in a direction perpendicular to the pusher pushing direction, the axial length of the chuck device can be shortened and the size can be reduced.

Before SL chuck jaws opening and closing mechanism includes an opening and closing drive source, and a cylindrical operation transmitting member for transmitting the operation of the opening and closing drive source to each chuck jaws, the fluid in the hollow portion of the cylindrical operation transmitting member place a pressure cylinder.
By disposing the fluid pressure cylinder in the hollow portion of the cylindrical motion transmission member, the chuck pawl opening / closing mechanism and the fluid pressure cylinder for pusher extrusion can be compactly disposed.

Further, the fluid pressure cylinder is disposed on the central axis, and the opening / closing drive source of the chuck pawl opening / closing mechanism is a fluid pressure cylinder that advances and retracts in a direction perpendicular to the central axis, and the chuck pawl opening / closing mechanism includes: A first motion converting mechanism that converts the advancing / retreating operation of the opening / closing drive source into a reciprocating operation in the direction along the central axis of the motion transmitting member; and the advancing / retreating operation of the motion transmitting member in the radial direction of each chuck claw. It is good also as a structure which has the 2nd operation | movement conversion mechanism part of the same number as a chuck | zipper nail | claw which each converts into opening / closing operation | movement.
By arranging a fluid pressure cylinder for pusher extrusion on the center axis and using a fluid pressure cylinder that moves back and forth in the direction perpendicular to the center axis as the opening and closing drive source for the chuck jaw opening and closing mechanism, This is a more compact arrangement with the fluid pressure cylinder. In addition, the first and second motion conversion mechanism sections and the second motion conversion mechanism section transmit the advance / retreat operation of the open / close drive source to the chuck claws in two stages, so that the chuck claws can be reliably opened and closed.

  The chuck device of the present invention is arranged radially on the outer periphery of the central shaft, each of which has a plurality of chuck claws that open and close in the radial direction to grip the workpiece, a chuck claw opening / closing mechanism that opens and closes each chuck claw, and the workpiece. A pusher that pushes in a direction along the central axis from a position held by the chuck claw, and a fluid pressure cylinder that causes the pusher to perform a workpiece pushing operation, and the fluid pressure cylinder and the chuck claw opening / closing mechanism are Since they are arranged side by side in the orthogonal direction, the pusher does not push the work when the chuck claw is holding the work, and the pusher stroke can be taken longer and a compact configuration can be achieved.

The chuck claw opening / closing mechanism has an opening / closing drive source and a cylindrical motion transmission member that transmits the operation of the opening / closing drive source to each chuck claw, and the fluid pressure is provided in a hollow portion of the cylindrical motion transmission member. Since the cylinder is arranged , the chuck pawl opening / closing mechanism and the pusher push-out fluid pressure cylinder can be arranged compactly.

  The fluid pressure cylinder is disposed on the central axis, the opening / closing drive source of the chuck pawl opening / closing mechanism is a fluid pressure cylinder that moves back and forth in a direction perpendicular to the central axis, and the chuck pawl opening / closing mechanism A first motion conversion mechanism that converts a forward / backward motion of the drive source into a forward / backward motion in a direction along the central axis of the motion transmission member; and a forward / backward motion of the motion transmission member in a radial direction of each chuck claw If there are as many second movement conversion mechanisms as the chuck claws, the chuck pawl opening / closing mechanism and the fluid pressure cylinder are more compactly arranged, and the chuck pawl opening / closing mechanism ensures the chuck pawls. Can be opened and closed.

It is a side view of the loader head provided with the chuck device concerning one embodiment of this invention. It is a bottom view of the loader head. (A) is III-III sectional drawing of FIG. 1 (A), (B) is sectional drawing which shows the different state. It is a front view which shows schematic structure of the loader apparatus provided with the loader head, and a machine tool. It is side surface sectional drawing of the loader apparatus. (A) is a diagram showing a state of the chuck device and the main spindle when a workpiece having a long axial length is gripped by the chuck device, and (B) is a chuck device when a workpiece having a short axial length is gripped by the chuck device. It is a figure which shows the state of a main axis | shaft. (A) is a diagram showing the state of the chuck device when a stepped workpiece having a small axial length of the small diameter portion is gripped from the large diameter portion side, and (B) is a diagram when the stepped workpiece is gripped from the small diameter portion side. It is a figure which shows the state of this chuck apparatus. (A) is a diagram showing the state of the chuck device when a stepped workpiece having a long axial length of the small diameter portion is gripped from the large diameter portion side, and (B) is a state where the stepped workpiece is gripped from the small diameter portion side. It is a figure which shows the state of this chuck apparatus. (A)-(D) is explanatory drawing of the setup change by the difference in the axial direction length of the workpiece | work in the conventional chuck device. (A)-(D) is explanatory drawing of the setup change by the difference in the shape of the workpiece | work in the conventional chuck | zipper apparatus.

An embodiment of the present invention will be described with reference to FIGS. The chuck device 1 is provided on a loader head 35 of a loader device 30 (FIGS. 4 and 5), and the illustrated loader head 35 is provided with two chuck devices 1 (1A, 1B). . Each chuck device 1 includes a plurality of (for example, three) chuck claws 2 for gripping the workpiece W, and the central axis O (O _A , O _B ) of the chuck device 1 from the position where the workpiece W is gripped by the chuck claws 2. And a pusher 3 for extruding along.

  As shown in FIG. 2, the plurality of chuck claws 2 are radially arranged on the outer periphery of the central axis O at equal intervals, and each grips and releases the workpiece W by opening and closing in the radial direction. As shown in FIG. 3, each chuck claw 2 can be attached to and detached from a claw support base 6 that engages with each guide groove 5 provided on the chuck installation surface of the loader head 35 and can advance and retreat in the radial direction by bolts 7. Installed on. The axial length of the chuck claw 2 is relatively long, and the large-diameter portion Wa (FIGS. 7 and 8) of the stepped workpiece W composed of the large-diameter portion Wa and the small-diameter portion Wb is replaced with the large-diameter portion Wa and It can be gripped from either side of the small diameter portion Wb.

  Each chuck claw 2 is driven to open and close in synchronization with each other by a chuck claw opening / closing mechanism 9 shown in FIG. The chuck pawl opening / closing mechanism 9 is provided along one opening / closing drive source 10 including a fluid pressure cylinder such as an air cylinder in which a piston rod 10a advances and retreats in a direction orthogonal to the central axis O, and a cylindrical hole 11 provided in the loader head 35. A motion transmission member 12 that is movable back and forth in the direction of the central axis O, a first motion conversion mechanism section 13 that converts the forward / backward motion of the open / close drive source 10 into a forward / backward motion in the direction along the central axis O of the motion transmission member 12, It consists of the same number of second motion conversion mechanisms 14 as the chuck claws 2 for converting the advance / retreat operation of the motion transmitting member 12 into the opening / closing operations of the chuck claws 2 in the radial direction.

  More specifically, the first motion conversion mechanism 13 is swingably supported by a support shaft 16 that is orthogonal to both the central axis O and the radial direction, and both sides of the support shaft 16 have two arm portions 17a and 17b. The link member 17 is used. Then, one arm portion 17a of the link member 17 engages with an engagement recess 18 formed in the piston rod 10a on the side of advancement / retraction in the opening / closing drive source 10, and the other arm portion 17b is engaged in the motion transmission. The engaging recess 19 is formed on the outer peripheral surface of the member 12.

  Further, the second motion conversion mechanism section 14 is supported by a support shaft 21 that is orthogonal to both the central axis O and the radial direction so as to be swingable, and both side portions of the support shaft 21 have two arm portions 22a and 22b. The link member 22 is provided. Then, one arm portion 22a of the link member 22 is engaged with an engagement recess 23 formed on the outer peripheral surface of the motion transmission member 12, and the other arm portion 22b is formed on the claw support base 6. The engaging recess 24 is engaged.

  When the piston rod 10a of the opening / closing drive source 10 is driven to advance and retract in the radial direction, the advance / retreat operation is transmitted to the operation transmitting member 12 via the first operation converting mechanism 13, and the operation transmitting member 12 is moved to the central axis O. Advancing and retreating along. Furthermore, the forward / backward movement of the motion transmitting member 12 is transmitted to each claw support base 6 via the second motion conversion mechanism section 14, and each claw support base 6 advances / retreats in the radial direction. Each chuck claw 2 opens and closes by the advance and retreat of the claw support base 6. As described above, the first and second motion conversion mechanisms 13 and 14 transmit the advance / retreat operation of the opening / closing drive source 10 to the chuck claw 2 in two stages, thereby ensuring that the chuck claw 2 is moved. Can be opened and closed.

  As shown in FIG. 2, the pusher 3 is a plate-like member having branch portions 3 a extending radially in, for example, three directions around the position of the central axis O. Each branch portion 3 a is arranged with a circumferential position shifted from the chuck claws 2.

  As shown in FIG. 3, the pusher drive mechanism that causes the pusher 3 to push the workpiece out includes a double-acting fluid pressure cylinder 26 such as an air cylinder. The fluid pressure cylinder 26 is disposed on the central axis O, and is fixed to the loader head 35 by a bolt 27 at a tip collar portion 26aa of the cylinder tube 26a. The motion transmitting member 12 has a cylindrical shape, and the cylinder tube 26a is slidably fitted in a hollow portion of the motion transmitting member 12.

  The cylinder tube 26a is provided with an advancing inlet port P1 and a retracting inlet port P2 at both ends in the central axis O direction. Each of these ports P1, P2 is connected to a fluid supply source (not shown) by piping. A piston 26b is slidably fitted along the central axis O in the cylinder tube 26a, and a piston rod 26c having a tip projecting from the chuck installation surface of the loader head 35 is integrally provided on the piston 26b. Yes. The pusher 3 is attached to a collar-like pusher attachment portion 26ca provided at the tip of the piston rod 26c by a bolt 28 (FIG. 2).

  The piston 26b moves forward and backward along the center axis O by supplying a fluid such as air into the cylinder tube 26a from the advance port P1 or the reverse port P2. Thereby, the pusher 3 attached to the tip of the piston rod 26b advances and retreats. When the pusher 3 advances, the workpiece W is pushed out in the direction along the central axis O from the position gripped by the chuck claws 2. Since the pusher drive mechanism is the fluid pressure cylinder 26, the maximum stroke S of the pusher 3 can be increased.

  4 and 5 show a loader device 30 in which the chuck device 1 is provided. The loader device 30 is a gantry type device that is installed above the machine tool 40 and is driven in an orthogonal coordinate system. The loader device 30 includes a traveling body 32 that travels along a horizontal installation rail 31 that is installed horizontally, and is provided with an elevating rod 34 via a front / rear moving table 33, and the loader head 35 is provided at the lower end thereof. . As shown in FIG. 1, the loader head 35 is rotatable about a fixed portion 36 fixed to the lifting rod 34 and a rotation center axis 37 inclined relative to the horizontal at an angle of 45 ° with respect to the fixed portion 36. The rotating unit 38 includes the two chuck devices 1A and 1B. By rotating the rotation part 38 around the rotation center axis 37 by 180 °, the position of the chuck devices 1A and 1B is converted into a downward position and a lateral position.

  In FIG. 4, the machine tool 40 is a lathe, for example, and includes a spindle 41 and a tool post 42. The spindle 41 has a chuck 43 at the tip thereof, and is rotatably supported by a spindle head 45 provided on the bed 44. The chuck 43 has a plurality of chuck claws 43 a for gripping the workpiece W. The tool post 42 is of a turret type, and any one of a plurality of tools T attached to the outer periphery is indexed to the cutting position. The tool post 42 is installed on the bed 44 via a feed base 46 so as to be movable in a direction along the axis of the main shaft 41 (Z-axis direction) and in a horizontal direction (X-axis direction) perpendicular thereto. The workpiece W is delivered to the chuck 43 of the main shaft 41 by the loader device 30.

The operation of the loader device 30 will be described.
At the standby position (not shown) of the unprocessed workpiece W, the loader device 30 grips the workpiece W with the chuck device 1 (for example, 1A) at the downward position of the loader head 35. At this time, the pusher 3 of the chuck device 1 is in a retracted position as shown in FIG. The loader head 35 that grips the workpiece W moves the traveling body 32 traveling along the installation rail 31 in the left-right direction (X-axis direction), moves back and forth the front-and-rear moving table 33 (Z-axis direction), and raises and lowers the lifting rod 34. The workpiece W is conveyed to a position in front of the spindle 41 of the machine tool 40 by (in the Y-axis direction). During this time, the rotation unit 38 of the loader head 35 is rotated 180 °, and the position of the chuck device 1 that grips the workpiece W at the downward position is changed to the horizontal position.

  Next, the front and rear moving table 33 is moved back and forth to advance the chuck device 1 toward the main shaft 41. When the end of the workpiece W gripped by the chuck device 1 on the opposite side to the chuck device side is positioned immediately in front of the chuck 43 of the spindle 41, the chuck claw 2 of the chuck device 1 is opened, and then the pusher is moved. 3 protrudes and pushes the workpiece W in the direction along the central axis O from the position held by the chuck claw 2. The pushed workpiece W is seated on the seating surface 43 b (FIG. 5) of the chuck 43 of the main shaft 41. After the seating, the chuck claws 43a of the chuck 43 are closed and the workpiece W is gripped. Thereby, the delivery of the workpiece W from the loader head 35 of the loader device 30 to the spindle 41 of the machine tool 40 is completed.

The position of the loader head 35 during delivery of the workpiece W is determined by teaching performed for each type of workpiece W so that the chuck claw 2 of the chuck device 1 and the chuck claw 43a of the chuck 43 of the spindle 41 do not interfere with each other. It is done. Since the pusher drive mechanism for operating the pusher 3 includes the fluid pressure cylinder 26 such as an air cylinder, the pusher 3 stops when it receives a reaction force of a certain magnitude or more during the protruding operation. As shown in FIG. 6 (A), if the chuck device 1 is holding a long workpiece W _L of the axial length, if the workpiece W _L is in contact with the pusher 3, the amount of protrusion of the pusher 3 is a distance a from the front end of the workpiece _{W L} to the seating surface 43b chuck 43 of the spindle 41. As shown in FIG. 6 (B), if the chuck device 1 is gripped a short workpiece W _S of the axial direction length, the amount of protrusion of the pusher 3, the seating from the tip of the workpiece W _S of the chuck 43 of the spindle 41 the distance a to the surface 43 b, a distance obtained by adding the distance b from the pusher 3 to the workpiece W _S.

  Further, since the chuck device 1 of the loader device 30 has a longer length in the axial direction of the chuck claw 2, as shown in FIGS. 7 and 8, a step having a large diameter portion Wa and a small diameter portion Wb is provided. The large diameter portion Wa of the workpiece W can be gripped from either the large diameter portion Wa or the small diameter portion Wb. Even if it is a stepped workpiece W (FIG. 7) in which the axial direction length of the small diameter portion Wb is short or a stepped workpiece W (FIG. 8) in which the axial direction length of the small diameter portion Wb is long, the chuck claw 2 All the workpieces W held by can be pushed out by the pusher 3.

  As described above, the chuck device 1 has high flexibility with respect to the size and shape of the workpiece W, and the change of the chuck pawl 2 and the pusher 3 by changing the type of the workpiece W can be minimized. Further, by using the fluid pressure cylinder 26 for pushing out the pusher 3, the pusher 3 can be designed not to push the work W when the chuck claw 2 is holding the work W. Therefore, the work gripping force of the chuck claw 2 can be reduced.

  In the chuck device 1, the fluid pressure cylinder 26 is arranged on the central axis O, and the chuck claw opening / closing mechanism 9 is arranged side by side, so that the axial length can be shortened. Further, since the fluid pressure cylinder 26 is disposed in the hollow portion of the cylindrical motion transmission member 12 of the chuck claw opening / closing mechanism 9, the chuck claw opening / closing mechanism 9 and the fluid pressure cylinder 26 are compactly arranged. In the case of this embodiment, the opening / closing drive source 10 of the chuck claw opening / closing mechanism 9 is a fluid pressure cylinder. By arranging the fluid pressure cylinder to move back and forth in the direction perpendicular to the central axis O, the chuck claw opening / closing mechanism 9 and the pusher The fluid pressure cylinder 26 for extrusion has a more compact arrangement.

DESCRIPTION OF SYMBOLS 1 ... Chuck apparatus 2 ... Chuck claw 3 ... Pusher 9 ... Chuck opening / closing mechanism 10 ... Opening / closing drive source 12 ... Operation transmission member 13 ... 1st operation conversion mechanism part 14 ... 2nd operation conversion mechanism part 26 ... Fluid pressure cylinder O ... Center axis W ... Workpiece

Claims (2)

A plurality of chuck claws that are radially arranged on the outer periphery of the central axis and each open and close in the radial direction to grip the workpiece, a chuck claw opening / closing mechanism that opens and closes each chuck claw, and a position at which the workpiece is gripped by the chuck claw A pusher that pushes out in the direction along the central axis, and a fluid pressure cylinder that causes the pusher to push out the workpiece,
The fluid pressure cylinder and the chuck claw opening / closing mechanism are arranged side by side in a direction perpendicular to the pusher pushing direction ,
The chuck claw opening / closing mechanism has an opening / closing drive source and a cylindrical motion transmission member that transmits the operation of the opening / closing drive source to each chuck claw, and the fluid pressure is provided in a hollow portion of the cylindrical motion transmission member. Chuck device with a cylinder . The fluid pressure cylinder is disposed on the central axis, the opening / closing drive source of the chuck pawl opening / closing mechanism is a fluid pressure cylinder that moves back and forth in a direction perpendicular to the central axis, and the chuck pawl opening / closing mechanism A first motion conversion mechanism that converts a forward / backward motion of the drive source into a forward / backward motion in a direction along the central axis of the motion transmission member; and a forward / backward motion of the motion transmission member in a radial direction of each chuck claw The chuck device according to claim 1 , wherein the number of second motion converting mechanism units is the same as that of chuck claws.

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