JP2014004651A - Rotary gripping chuck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary gripping chuck that can grip and release a component or rotate the gripped component and does not use compressed air.SOLUTION: A collet 3 into which what is called a component W can be inserted rotates through rotational driving by a collet rotating motor 2, and a male screw member 7 engaging a female member 6 rotates through rotational driving by a collet opening/closing motor 1. When the male screw member 7 rotates, the female member 6 moves downward while having its rotation restricted by a rotation stop shaft 11. The female screw member 6 has a collet receiver 4 arranged rotatably across a support member 5, and the collet receiver 4 moves in the direction to abut against a taper 3a of the collect 3 through the rotation of the male member 7, so that the collet 3 grips the component W. Gripping operation of the collet 3 is thereby performed through the rotational driving by the collect opening/closing motor 1, thereby eliminating the need for conventional compressed air supply.

Description

  The present invention relates to a rotary gripping chuck that can grip, open, or rotate a workpiece that has a substantially cylindrical shape or a substantially columnar shape.

  A conventional rotary gripping chuck 110 shown in Patent Document 1 is known and will be described below with reference to FIG. The rotary gripping chuck 110 is inserted through the part W, and has a collet 105 having a tapered outer end and a threaded portion 105a at the outer end, and a piston 108 connected to the collet 105 and slidably disposed. The collet receiver 104 includes the collet 105 and includes a tapered hole 104a, a driven gear 113 that is fixed to the collet receiver 104 and rotates integrally with the collet receiver 104, and the rotation can be transmitted to the driven gear 113. And a motor unit 120. The motor unit 120 is associated with a motor 116, which is an example of a rotational drive source having an output shaft 116a, a drive gear 115 fixed to the output shaft 116a, and the drive gear 115 and the driven gear 113. The intermediate gear 114 is rotatably arranged. Next, the operation will be described. When compressed air is supplied to the piston 108 from an air tank connected to an air compressor (not shown), the collet 105 inserted through the component W operates together with the piston 108, and the taper hits the taper hole 104a. In contact with it, the inner diameter of the collet 105 contracts. As a result, the component W is gripped by the collet 105 and rotated by receiving the rotational drive of the motor 116. When the rotation drive of the motor 116 is stopped, the compressed air is supplied to the piston 108, the collet 105 is restored, and the contact state of the taper and the taper hole 104a is released. Thereby, the component W can be extracted from the collet 105. That is, the conventional rotary gripping chuck 110 grips or releases the component W inserted into the collet 105 by the reciprocating movement of the piston 108 and rotates the component W gripped by the collet 105 by the rotational drive of the motor 116. There are features. Therefore, for example, when the rotary gripping chuck 110 is mounted on a cutting apparatus, the part W can be rotated while gripping, releasing or gripping the outer diameter of the part W that is a round bar. it can. Further, if the part W is a substantially cylindrical fastening part having a male thread or a female thread, the fastening part can be fastened to the object with a predetermined tightening torque. Used in production sites.

Japanese Patent No. 4227551

  Incidentally, the conventional rotary gripping chuck 110 is required to always rotate the gripped component W integrally with the collet 105. For example, in the case of the above-described cutting process, torque is applied to the part W due to the contact of the cutting tool, so that the part W slides and rotates with respect to the collet 105 and correct cutting cannot be performed. Alternatively, in the case of the above-described fastening operation, torque is applied to the component W due to the increase in the tightening torque, and thus the component W slides and rotates with respect to the collet 105 so that correct fastening operation cannot be performed. Therefore, the conventional rotary gripping chuck 110 is required to have a strong gripping force that does not cause the component W to idle. For this reason, the diameter of the piston 108 must be increased so that compressed air can be received in a wider area, and the collet 105 must press the collet receiver 104 strongly. As a result, the taper of the collet 105 is strongly pressed by the taper hole 104a of the collet receiver 104. Therefore, the collet 105 contracts further in the direction in which the inner diameter of the collet 105 becomes smaller, and the force for gripping the component W gradually increases. In other words, the conventional rotary gripping chuck 110 outputs a strong gripping force, but has a problem of increasing the size because the piston 108 has a large diameter. In addition, since the conventional rotary gripping chuck 110 grips and releases the component W by the reciprocating movement of the piston 108, the sliding portion of the piston 108 is easily worn, and compressed air leaks from the sliding portion. easy. Therefore, the conventional rotary gripping chuck 110 has a problem that air leakage occurs due to wear of the sliding portion of the piston 108 and has a serious defect that causes a decrease in gripping force of the component W. In order to prevent the above-described air leakage, the airtightness of the piston 108 must be increased. However, this requires an increase in the processing accuracy of the sliding portion or the wear resistance of the sliding portion, and there is a problem that the cost of parts used for the sliding portion is increased. By the way, the compressed air in the air tank is generally kept almost constant by the air compressor so that the pressure does not fluctuate, while the compressed air discharged from the air tank is not supplied to the piston 108. The flow rate of the compressed air is adjusted in advance by an adjustment valve (not shown) and supplied to the piston 108 almost uniformly. That is, since the piston 108 slides at a substantially constant force and speed by compressed air having a constant pressure and a constant flow rate, the gripping speed and gripping force of the collet 105 are constant in the gripping process of the component W each time. is there. For this reason, in the case of multi-product production in which parts having different softness are frequently replaced, particularly soft parts are seriously damaged. Therefore, the conventional rotary gripping chuck 110 cannot easily reduce the gripping force of the component according to the softness of the component, and has a problem that it cannot cope with multi-product production.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a rotary gripping chuck capable of gripping, releasing, or rotating a gripped component without using compressed air. In order to achieve this object, the present invention provides a gripping hole through which a so-called part can be inserted and a collet formed with a taper on the outer periphery thereof, and slides in the extending direction of the collet so as to abut against or from the taper. A collet receiver that is separated, a support member that rotatably supports the collet receiver, a screw member that is fixed to the support member, a male screw member that is screwed to the female screw member, and one end of the male screw member A fixed driven gear, a drive gear engaged with the driven gear, a first rotary drive source directly connected to the drive gear, a second rotary drive source directly connected to the collet, and the first and second rotary drives It comprises a fixing member for fixing and supporting each source, and a detent shaft fixed to the supporting member and inserted through the fixing member. The first rotational drive source is preferably connected to a control device that stores a plurality of torques that the output shaft exerts during rotation.

  In the rotary gripping chuck 20 of the present invention, since the gripping hole of the collet 3 is contracted by receiving the rotational drive of the first rotational drive source, it is not necessary to supply compressed air as in the prior art. For this reason, there is an advantage that there is no decrease in gripping force due to leakage of compressed air as in the prior art. Further, the rotary gripping chuck 20 has an advantage that it is more compact than the conventional one because a large-diameter piston is not required as in the prior art even when a strong gripping force is required.

  Further, the rotary gripping chuck 20 of the present invention is applied to the male screw member 7 in order to perform rotational drive control of the output shaft 1a of the first rotational drive source based on a preset torque in each gripping operation of the component W. There is an advantage that the axial force can be made substantially constant, and the force applied to the component W becomes almost constant. In addition, since a plurality of torques can be stored in the control device 41 in advance, an appropriate gripping force can be set according to parts having different softness. As a result, the rotary gripping chuck 20 of the present invention has an advantage that it can flexibly cope with multi-product production as compared with the conventional one.

It is a partially cutaway sectional view of an embodiment according to the present invention. It is a partially cutaway sectional view showing a conventional example.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG. The rotary gripping chuck 20 of the present invention includes a collet 3 having a gripping hole through which a so-called component W can be inserted, a collet rotation motor 2 that is an example of a second rotational drive source that imparts rotation to the collet 3, and a first rotation. It comprises a rotatable collet receiver 4 that reciprocates in response to the rotation of a collet opening / closing motor 1, which is an example of a drive source.

  The collet 3 is formed such that the grip hole has a size slightly larger than the outer diameter of the component W, and includes a plurality of notches 3b in the axial direction from the tip. The outer shape of the collet 3 includes a taper 3a formed so as to expand toward the front end side and a male screw formed at the rear end, and the male screw extends in the axial direction of the collet 3. A groove is formed. The collet 3 is provided with a rotation transmission shaft 26 screwed to the male screw, and the rotation transmission shaft 26 is rotatably supported by a flange 25. A coupling 27 is disposed on the collet 3 and the rotation transmission shaft 26, and this coupling 27 is fixed to the outer shape of the tip of the rotation transmission shaft 26 by a screw 28, while in the groove of the collet 3. The collet 3 has an anti-rotation function that prevents the collet 3 from being completely loosened from the rotation transmission shaft 26 by the fitted screw. Further, a hexagonal column is integrally formed at the upper end portion of the rotation transmission shaft 26, and the collet 3 is always rotated integrally with the rotation transmission shaft 26 when the hexagonal column rotates. The

  The collet rotation motor 2 is arranged so that the hexagonal column of the rotation transmission shaft 26 is fitted into the hexagon hole formed in the output shaft 2 a, and is fixed to the motor mounting plate 21. The collet rotation motor 2 is connected to a control device 42 that controls the rotation drive of the collet rotation motor 2. The control device 42 controls the rotation of the output shaft 2a so as to exhibit a predetermined torque and rotation speed, respectively. In addition, since rotation control of the collet rotation motor 2 and the control apparatus 42 is disclosed by patent 3357497, the detailed description is abbreviate | omitted here.

  On the other hand, the collet opening / closing motor 1 is provided with a hexagonal hole on the output shaft 1a, and is fixed to the motor mounting plate 21 and connected to a control device 41 that controls the rotation of the output shaft 1a. . Since the collet opening / closing motor 1 and the control device 41 are also disclosed in Japanese Patent No. 3357497 as described above, a detailed description of the rotation control is omitted here.

  A hexagonal bar 22 having screws at both ends is fixed to the motor mounting plate 21 with nuts, and a fixing member 10 that fixes and supports the flange 25 is fixed to the other end of the hexagonal bar 22 with nuts. Has been. Further, the fixing member 10 is provided with a flange 23 fixed side by side with the flange 25, and the rotation transmission fitted in the hexagon hole of the output shaft 1a of the collet opening / closing motor 1 is provided on the flange A23. A shaft 24 is rotatably arranged. Further, the fixed member 10 is provided with a flanged linear bush 31 extending in parallel with the rotation transmission shaft 26, and a through hole is provided so as to coincide with the inner diameter of the flanged linear bush 31.

  The rotation transmission shaft 24 is provided with a drive gear 9 fixed by positioning pins and screwing, and a driven gear 8 engaged with the drive gear 9 is rotatably arranged on the outer periphery of the flange 25. . In addition, a hole larger than the diameter of the rotation transmission shaft 26 is provided at the center of the driven gear 8 and a male screw member 7 having a hollow hole communicating with the hole is fixed.

  The external thread member 7 has an outer shape formed of a trapezoidal screw and is configured to rotate in conjunction with the rotation of the collet opening / closing motor 1. A female screw member 6 is screwed onto the male screw member 7, and the female screw member 6 is disposed so as to include the coupling 27.

  A support member 5 is fixed to one end of the female screw member 6 by screwing, and a detent shaft 11 inserted into the flanged linear bush 31 is fixed to the support member 5. For this reason, when the collet opening / closing motor 1 is rotationally driven, the female screw member 6 is configured to be movable in the ascending / descending direction together with the support member 7 and the detent shaft 11. A bearing case 30 that rotatably supports a bearing is fixed to the support member 7, and a collet receiver 4 that is inserted through the bearing and includes the collet 3 is rotatably disposed. The

  The collet receiver 4 includes a screw formed on the outer shape of one end thereof, and a tapered hole 4a formed inside the tip portion. The tapered hole 4a substantially coincides with the taper 3a of the collet 3. Formed as follows. Further, since the fixing nut 29 is screwed into the screw of the collet receiver 4, the collet receiver 4 is configured to be movable in conjunction with the elevation of the female screw member 6.

  Next, the operation of the rotary gripping unit 20 of the present invention will be described below. First, after a component W is inserted into the collet 3 by an operator (not shown), the collet opening / closing motor 1 is reversely rotated so as to exert a predetermined torque in response to a command from the control device 41. The combined driven gear 8 rotates forward together with the male screw member 7. As a result, the female screw member 6 moves downward in FIG. 1, and the tapered hole 4 a of the collet receiver 4 comes into contact with the tapered 3 a of the collet 3. Gradually, the abutting force increases and the gripping hole of the collet 3 becomes small, and the part W is held by the gripping hole of the collet 3. The control device 41 stops when the collet opening / closing motor 1 exerts a predetermined torque, but since the axial force is generated in the female screw member 6 and the male screw member 7 even after the stop, the collet 3 The gripping force generated in the operation continues to be maintained. Next, the control device 42 causes the collet rotation motor 2 to rotate forward at a predetermined torque and rotation speed. As a result, the fixing member 10 is lowered to a predetermined position by a lifting / lowering means (not shown), and the component W gripped and rotated by the collet 3 is screwed into a workpiece (not shown). When the control device 42 reaches a predetermined torque, the control device 42 stops the rotation of the collet rotation motor 2, and then the collet opening / closing motor 1 so that the control device 41 exhibits a torque higher than the previous torque and by a predetermined angle. Rotate forward. As a result, the male screw member 7 reverses, so that the collet receiver 4 moves upward and the tapered hole 4 a of the collet receiver 4 is separated from the taper 3 a of the collet 3. Therefore, the collet 3 releases the part W that has been gripped, and the elevating means returns to complete a series of fastening operations.

  As described above, the rotary gripping chuck 20 of the present invention receives the rotational drive of the collet opening / closing motor 1 and the gripping hole of the collet 3 contracts, so that it is not necessary to supply compressed air as in the prior art. For this reason, there is an advantage that there is no decrease in gripping force due to leakage of compressed air as in the prior art. Further, the rotary gripping chuck 20 has an advantage that it is more compact than the conventional one because a large-diameter piston is not required as in the prior art even when a strong gripping force is required. Furthermore, the rotary gripping chuck 20 of the present invention controls the rotational drive of the output shaft 1a of the collet opening / closing motor 1 based on the torque set in advance according to the softness of the component W in each gripping operation of the component W. Therefore, there is also an advantage that the force applied to the component W can be easily changed to an optimum value according to the type of the component W each time. Further, a plurality of rotational speeds of the output shaft 1a of the collet opening / closing motor 1 can be set in the control device 41 in advance for each type or size of the component W. There is also an advantage that it can be set optimally depending on the type. On the other hand, the collet rotation motor 2 controls the rotational drive of the output shaft 2a with a preset torque and rotation speed. Therefore, the rotary gripping chuck 20 of the present invention can stably fasten the component W with a predetermined tightening torque. There is also an advantage that fastening work can be realized.

  Although the rotary gripping unit 20 of the present invention has been described with respect to the embodiment of the tip tool of the fastening device, the present invention is not limited to this. For example, it may be mounted on a machine tool that performs cutting. Yes. Moreover, although the thread part of the said internal thread member 6 and the said external thread member 7 was demonstrated as a trapezoidal screw, it is not limited to this, For example, a triangular thread like a metric thread may be sufficient. Further, it is needless to say that a right-handed screw or a left-handed screw is selected for each of the screws that are the connecting portions of the collet 3 and the rotation transmission shaft 26 based on the direction of the load torque generated in the collet 3.

DESCRIPTION OF SYMBOLS 1 Collet opening / closing motor 1a Output shaft 2 Collet rotation motor 2a Output shaft 3 Collet 3a Taper 3b Notch 4 Collet receptacle 4a Tapered hole 5 Support member 6 Female screw member 7 Male screw member 8 Drive gear 9 Drive gear 10 Fixing member 11 Non-rotation Shaft 20 Rotary gripping chuck (present invention)
DESCRIPTION OF SYMBOLS 21 Motor mounting plate 22 Hexagon stick 23 Flange 24 Rotation transmission shaft 25 Flange 26 Rotation transmission shaft 27 Coupling 28 Fixing screw 29 Fixing nut 30 Bearing case 31 Linear bush with flange 41 Control device 42 Control device 104 Collet receiver 104a Taper hole 105 Collet 105a Screw part 108 Piston 110 Rotary gripping chuck (Conventional)
113 driven gear 114 intermediate gear 115 driving gear 116 motor 116a output shaft 120 motor unit W parts

Claims (2)

  A so-called grip hole through which a part can be inserted and a collet formed with a taper on the outer periphery, a collet receiver that slides in the extending direction of the collet and abuts against or away from the taper, and the collet receiver is rotatable A support member supported on the support member, a screw member fixed to the support member, a male screw member screwed to the female screw member, a driven gear fixed to one end of the male screw member, and the driven gear engaged Drive gear, a first rotation drive source directly connected to the drive gear, a second rotation drive source directly connected to the collet, a fixing member for fixing and supporting each of the first and second rotation drive sources, and the support A rotary gripping chuck comprising a non-rotating shaft fixed to a member and inserted through the fixing member.   The rotary gripping chuck according to claim 1, wherein the first rotation drive source is connected to a control device that stores a plurality of torques that the output shaft exerts during rotation.

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