JP3794558B2 - Rotating clamp cylinder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a swivel clamp cylinder, and more particularly to a clutch clamp that protects a swivel motion generation mechanism from being damaged when an excessive swiveling torque is applied to the swivel motion generation mechanism via a clamper. .
[0002]
[Prior art]
As a conventional swiveling clamp cylinder, a piston and a piston rod are combined together, a swiveling groove is engaged with the piston rod, and a guide member (guide ball) is engaged and guided in the swiveling groove on the cylinder tube side (non-rotating side: fixed side). When the piston moves in the axial direction, the turning groove is guided along the stationary guide ball, and the piston rod performs turning and axial movement. A clamper provided at the tip of the piston rod that clamps and unclamps the workpiece from the axial direction is known (for example, JP-A-2001-182713).
[0003]
[Problems to be solved by the invention]
In the above-described swivel type clamp cylinder, the piston moves with the fluid pressure in the axial direction, and the clamper swivels. Therefore, if the swirl of the clamper is hindered by unexpected external interference during the swivel operation. The fluid pressure acting on the piston may generate an excessive turning torque between the guide member of the turning motion generation mechanism and the turning groove, and the turning motion generation mechanism may be damaged. A similar situation also occurs when an unexpected external force acts on the clamp cylinder clamper in the unclamped state, and an excessive turning torque acts on the turning motion generating mechanism via the clamper.
The subject of this application is providing the turning clamp cylinder which prevented damage to the turning motion generation | occurrence | production mechanism of the turning clamp cylinder in such a case.
[0004]
[Means for Solving the Problems]
In order to solve the above problem, in the swivel clamp cylinder of the present application, when the piston moves in the axial direction in the cylinder tube, the piston rod swivels through a swivel motion generating mechanism including a swivel groove and a guide member guided by the swivel groove. In a pivoting clamp cylinder that moves in the axial direction and clamps the workpiece with a clamper integrated with the piston rod , the pivoting rod protrudes backward from the piston, and the pivoting rod is protruded from the cylinder tube. fitted into the central hole of the rotatable with the intermediate member Te, turning one of turning groove and the guide member to the turning operation rod, and the guide member to the turning groove in Rukoto provided the other to the intermediate member engaged usher movement constitute a generating mechanism disposed between the intermediate member and the cylinder tube, the medium until the turning torque acting on the intermediate member is the allowable torque Member of the cylinder tube and integrally connected Suruga, and characterized in that the intermediate member to release the coupling between the intermediate member and the cylinder tube is interposed a structure the clutch structure to pivot when it exceeds the allowable torque To do.
[0005]
Specifically, the piston and the piston rod are integrally formed, and the turning rod is fitted into the center hole of the intermediate member that is rotatably provided to the head cover that closes one end of the cylinder tube. Engaging / disengaging recesses for engaging / disengaging the engaging / disengaging member and the engaging / disengaging member between the intermediate member and the head cover by forming one of the revolving groove and the guide member and the other remaining on the intermediate member to constitute a revolving motion generating mechanism. and the these disengagement member and disengaging the groove is interposed clutch structure comprising a biasing member for engaging with each other, characterized by comprising.
More specifically, the intermediate member can be moved by a predetermined amount in the axial direction relative to the head cover, and an engagement / disengagement groove is formed on one end surface of the intermediate member in the axial direction and one of the head cover portions facing the end surface in the axial direction. The other is provided with an engaging / disengaging ball, and the intermediate member is urged by an urging member in a direction in which the engaging / disengaging groove and the engaging / disengaging ball are engaged to constitute a clutch mechanism. More specifically, the head cover is composed of a head cover main body formed with an accommodation hole for the intermediate member facing the piston rod side, and a cap for closing the accommodation hole. The ball holder portion of the intermediate member protrudes from the center hole of the cap and is held by the guide ball to engage with the turning groove of the turning rod. A spring provided with an engaging / disengaging ball, forming a radial V-groove on the inner end face of the cap facing the engaging / disengaging ball, and biasing the intermediate member forward in the axial direction between the bottom surface of the housing hole of the head cover body and the intermediate member. Intervening.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2, the cylinder tube 1 is composed of an outer tube 2 and an inner tube 3. The outer tube 2 is made of an aluminum alloy drawing material. As shown in FIGS. 5 and 6, a plurality of (eight) concave grooves 5 are drawn at equal angular intervals in the inner surface of the center hole (bore) 4 in the circumferential direction. Sometimes pre-formed. On the other hand, the inner tube 3 shown in FIG. 4 is made of stainless steel, and a plurality of (four in this case) notches 6 for passing pressurized fluid are formed at equal angular intervals in the circumferential direction at the head side end. ing. The outer peripheral surface of the inner tube 3 is fitted into the bore 4 of the outer tube 2, and eight fluid passages 7 are formed along the longitudinal direction of the cylinder tube 1 by the outer peripheral surface of the inner tube 3 and the plurality of concave grooves 5 of the outer tube 2. Is to be formed. The rod-side and head-side ends of these fluid passages 7 are opened outward from the axis. In the attached state, the rod side end 3 a of the inner tube 3 protrudes a predetermined amount toward the rod side from the rod side end 2 a of the outer tube 2. Therefore, the rod side opening 7a of the fluid passage 7 is located on the head side (downward) in the axial direction from the rod side end 3a of the inner tube 3 (FIG. 7).
[0007]
The cylinder tube 1 includes a head chamber 10 and a rod cover 11, and both ends in the axial direction are closed to form a cylinder chamber 12 inside. A piston 13 is fitted in the cylinder chamber 12 so as to be capable of reciprocating in the axial direction, and the cylinder chamber 12 is partitioned into a head side cylinder chamber 14 and a rod side cylinder chamber 15. The piston 13 is integrally provided with a piston rod 16 on the rod side, and the piston rod 16 projects forward from the rod cover 11 along the axis. A clamper 17 is integrally attached to the protruding portion of the piston rod 16.
[0008]
As shown in FIGS. 1 and 7, the rod cover 11 has an annular tube fitting groove 21 formed on the head side, and a fitting portion 20 in which a radially inner portion is fitted to the inner peripheral surface of the inner tube 3. It has become. The tube fitting groove 21 includes an end fitting portion 21a in which the inner surface of the radially outer wall portion 22 is fitted to the end portion of the outer tube 2, and a diameter smaller than that of the end fitting portion 21a. It has a stepped shape including an end receiving portion 21b that receives the end. The end fitting portion 21a of the outer tube 2 has a female screw portion 21c formed on the head side portion thereof, and a male screw portion 23 formed on the outer periphery of the rod side end portion of the outer tube 2 is screwed to the female screw portion 21c. The rod side end surface 2a of the outer tube 2 is in contact with the stepped portion 21d. In this state, an annular communication path 25 is formed by a space surrounded by the rod-side end outer peripheral surface of the inner tube 3, the end receiving portion 21 b, and the rod-side end face 2 a of the outer tube 2. Is in communication with the rod side openings 7a of the eight fluid passages 7.
[0009]
A pair of supply / discharge ports 30 and 31 are provided on one side surface of the rod cover 11. One supply / discharge port 30 communicates with the annular communication passage 25 via a fluid passage 32. The other supply / discharge port 31 communicates with the rod-side cylinder chamber 15 via another fluid passage 33 of the head cover 10.
[0010]
The head cover 10 includes a head cover main body 35 and a cap 36. The head cover main body 35 has a stepped shape including a large diameter portion 38 having a threaded portion 37 formed on the outer periphery and a fitting portion 39 that fits on the inner periphery of the inner tube 3. The stepped portion is a contact surface 40 in which the head-side end surface 3 b of the inner tube 3, the female screw portion 42 of the outer tube 2, and the stepped portion 43 of the bore 4 are in contact with each other to block the head-side opening 7 b of the fluid passage 7. A circumferential groove 44 is formed with a predetermined width from the contact surface 40 toward the rod. A male screw portion 37 on the outer periphery of the head cover main body 35 is screwed into the female screw portion 42 formed on the inner side of the head side end of the bore 4 of the outer tube 2. When the rod cover 11 and the head cover 10 are integrally screwed to the rod side and the head side of the outer tube 2, the head side end 3b of the inner tube 3 is brought into contact with the contact surface 40, and the rod side end 3a. Is in contact with the bottom surface of the end receiving portion 21b of the rod cover 11 in a state protruding from the rod side end surface of the outer tube 2 and sandwiched between the rod cover 11 and the head cover 10 from both sides of the axis. Is done. The fitting portion 39 of the head cover body 35 to the inner tube 3 is formed with a plurality of (four in this case) concave grooves 46 (FIG. 6) for fluid passage in the circumferential direction. The circumferential groove 44 and the head side cylinder chamber 14 are communicated with each other. The notch 6 of the inner tube 3 opens into the circumferential groove 44, and each notch 6 and each of the plurality of fluid passages 7 are annular grooves 47 formed at positions close to the step portion 43 of the outer tube 2. Communicate with each other. Accordingly, the pressurized fluid supplied from the one supply / discharge port 30 is communicated with the communication passage 25, the plurality of fluid passages 7, the annular groove 47, the notch 6 of the inner tube 3, the circumferential groove 44, and the concave groove of the head cover body 35. It is supplied to the head side cylinder chamber 14 through 46.
[0011]
The cap 36 closes a receiving hole, which will be described later, and has an outer diameter that is somewhat smaller than the fitting portion 39 of the head cover main body 35. In order to allow the pressurized fluid supplied to the head side cylinder chamber 14 to efficiently act on the piston 13, the front surface (rod side surface) of the cap 36 of the head cover 10 is shallow in the radial direction at equiangular intervals in the circumferential direction. A groove 49 and an annular groove 50 on the center side connected to each of the grooves 49 are formed. Even if the end surface on the head side of the piston 13 abuts against the front surface of the cap 36, the pressurized fluid acts on the piston 13 with certainty. ing.
A recess 51 into which a ball holder portion 58 (described later) enters and exits is formed at the rear portion (head side) of the piston 13. The swing operation rod 52 projects rearward and concentrically with the axis of the piston 13. It is attached to. On the outer periphery of the swivel rod 52, two swivel grooves 55 each including an axial cam groove 53 and a cam groove 54 obliquely inclined in the circumferential direction are formed at symmetrical positions.
[0012]
Further, the head cover main body 35 is formed with an accommodation hole 57 of the intermediate member 56 opened to the rod side. The accommodation hole 57 includes a small-diameter ball holder portion 58 and a large-diameter spring receiving portion 59. The intermediate member 56 having a stepped shape is fitted so as to be rotatable and movable in the axial direction. The cap 36 is attached with a screw 60 so as to close the opening of the accommodation hole 57 of the head cover main body 35, and the ball holder portion 58 protrudes from the center hole 36 a of the cap 36 to the rod side. A pair of guide balls 62 as guide members held in a ball holder portion 58 are inserted into the center hole 61 of the intermediate member 56 so as to be movable in the axial direction and the rotational direction, respectively. The turning motion generating mechanism 63 is configured by being guided and engaged with the turning groove 55 of the rod 52 for use.
[0013]
Between the intermediate member 56 and the head cover 10 integrated with the cylinder tube 1, until the intermediate member 56 exceeds a predetermined amount of turning torque (allowable torque) via the turning motion generating mechanism 63, the intermediate member 56. Is coupled to the cylinder tube 1 side, and when a torque exceeding the allowable torque is applied, a clutch mechanism 65 is provided for releasing the coupling of both members and rotating the intermediate member 56 relative to the cylinder tube 1.
[0014]
In the clutch mechanism 65, a V-groove 67 is formed on the head side end surface of the cap 36 as an engaging / disengaging recess extending in the radial direction. An engaging / disengaging ball 68 as an engaging / disengaging member is provided on the end surface of the spring receiving portion 59 of the intermediate member 56 facing the V-groove 67 in the axial direction, and the receiving hole bottom portion of the head cover 10 and the spring receiving portion of the intermediate member 56 are provided. A disc spring 69 as an urging member for urging the intermediate member 56 in the rod direction is interposed between the portion 59 and the engagement / disengagement ball 68 so that the engagement / disengagement ball 68 can be engaged with and disengaged from the V groove 67 by the spring force. Match. In this configuration, the permissible torque is set by the spring force of the disc spring 69, and the permissible torque is set to a normal operation (by moving the piston 13 in the axial direction by the fluid, the swirl motion generating mechanism 63 performs the third operation. In the operation in which the clamper 17 is turned 90 degrees between the unclamping position A and the clamping position B shown in the drawing and moved in the axial direction), the engagement / disengagement ball 68 does not come off from the V groove 67. While the clamper 17 is turning, a dangerous torque is generated in the intermediate member 56 such that an unexpected external force acts to prevent the turning and damage the guide ball 62 or the guide groove 55 of the turning motion generating mechanism 63. Alternatively, when an unexpected external force is applied to the clamper 17 in the unclamping position and the above dangerous torque is generated in the intermediate member 56, As the intermediate member 56 moves in the circumferential direction, the engagement / disengagement ball 68 rides on the V-groove 67, pushes the intermediate member 56 toward the head against the spring force of the disc spring 69, and the V-groove 67 and the engagement / removal ball 68. The intermediate member 56 is freely rotated in the circumferential direction.
[0015]
In the above configuration, when fluid is supplied to the rod side cylinder chamber 15 from the state of FIG. 2 in the unclamping position A (the clamper 17 turning position is indicated by a two-dot chain line in FIG. 3), the piston 13 is moved to the piston rod 16 and the clamper 17. Then, it is moved downward along the axis along with the turning rod 52. In normal operation, dangerous torque exceeding the allowable torque does not act on the intermediate member 56 via the turning groove 55 and the guide ball 62, so the V groove 67 and the engagement / disengagement ball 68 are caused by the spring force of the disc spring 69. The intermediate member 56 is integrally coupled to the cylinder tube 1 while maintaining the engagement. As a result, the turning groove 55 of the turning rod 52 is guided by the guide ball 62 on the tube side (fixed side), and the clamper 17 turns 90 degrees while moving downward from the unclamping position A, and thereafter The workpiece W is lowered toward the workpiece W while maintaining the turning position, and the workpiece W is clamped at the clamp position B (FIG. 1).
[0016]
During the turning of the clamper 17 in the clamping operation, for example, when a workpiece transfer robot or the like is present at a position where it should not exist due to malfunction, and interferes with the clamper 17 and prevents the clamper 17 from turning, Is still supplied to the rod-side cylinder chamber 15, and the piston 13 generates an excessively dangerous torque exceeding the allowable torque, which causes the turning groove 55 to turn with respect to the guide ball 62 in an attempt to move downward. Let Then, the intermediate member 56 is rotated by the dangerous torque, and the engagement / disengagement ball 68 rides on the V-groove 67 and depresses the intermediate member 56 toward the head against the spring force of the disc spring 69 to engage / disengage from the V-groove 67. The ball 68 is disengaged, the intermediate member 56 is released from the cylinder tube 1 side, and rotates freely while the turning groove 55 and the guide ball 62 are engaged. As described above, when the torque forcing the turning groove 55 to rotate with respect to the guide ball 62 is applied, the clutch mechanism 65 is operated and the intermediate member 56 is rotated freely. Therefore, the turning motion generating mechanism 63 is generated with an unreasonable torque. Can be prevented from being damaged, and the life of the apparatus can be extended. Needless to say, the same is true when an excessive external force that turns the piston 13 (piston rod 16) is applied via the clamper 17 of the present clamping cylinder at the unclamping position A.
[0017]
Next, the pressure fluid supplied from the supply / discharge port 30 to the clamper 17 at the clamp position A in FIG. 1 is connected to the communication passage 25, the plurality of fluid passages 7, the annular groove 47, and the notch 6 of the inner tube 3. , Are supplied to the head side cylinder chamber 14 via the circumferential groove 44, the concave groove 46 of the head cover main body 35, and the grooves 49, 50, and pushes the piston 13 upward. As a result, the clamper 17 moves straight in the axial direction from the clamp position B in FIG. 3 and then turns 90 degrees toward the unclamp position A while moving further forward in the axial direction and stops there. Since a plurality of fluid passages 7 are formed, a fluid supply amount to be supplied to the head-side cylinder chamber 14 may be ensured by a flow rate that passes through the total cross-sectional area of the plurality of fluid passages 7. The cross-sectional size of the fluid passage 7 may be smaller than that of the conventional case where the number of the fluid passages 7 is limited to one. Therefore, in the double tube type cylinder tube structure, the wall thickness of the outer tube 2 can be reduced, which greatly contributes to the reduction of the cylinder outer diameter. Further, since the plurality of fluid passages 7 are provided at equiangular intervals in the circumferential direction with respect to the cylinder tube, the outer peripheral surface of the inner tube 2 from the radially outer side in the circumferential direction by the fluid pressure passing therethrough. Since the pressure is evenly applied, the inner tube can be deformed evenly as compared with the case of having one fluid passage as in the prior art, and the sliding movement of the piston is not hindered.
[0018]
【The invention's effect】
As described above, in the swivel clamp cylinder of the present application, the swiveling rod is integrally projected rearward from the piston, and the swiveling rod is fitted in the center hole of the intermediate member which can be pivoted with respect to the cylinder tube, and the swiveling motion is performed. By providing one of the swiveling groove and the guide member on the rod for use and the other on the intermediate member, the guide member is guided and engaged with the swiveling groove to constitute a turning motion generating mechanism, and between the intermediate member and the cylinder tube, The intermediate member is integrally coupled with the cylinder tube until the turning torque acting on the intermediate member reaches the allowable torque, but when the allowable torque is exceeded, the intermediate member and the cylinder tube are released to rotate and the intermediate member rotates. In the normal operation, the intermediate member is integrally coupled with the cylinder tube, and the piston is moved in the axial direction. It is, can clamp the pivot and by axially moving the workpiece between an unclamped position and a clamped position by the turning motion generating mechanism clamper. In addition, when the clamper is prevented from turning during turning, or excessive turning torque is applied from the outside via the unclamped clamper, the turning motion generating mechanism inside the cylinder exceeds the allowable torque. When torque is applied, the clutch mechanism is activated and the intermediate member releases the coupling to the cylinder tube side so that the intermediate member rotates freely. Therefore, the turning motion generating mechanism interposed between the intermediate member and the piston rod side is damaged. Can be prevented and the life of the apparatus can be extended.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a clamp cylinder in a clamped state.
FIG. 2 is a longitudinal sectional view showing the same section as FIG. 1, but showing an unclamped state.
3 is a plan view of FIG. 1. FIG.
FIG. 4 is a longitudinal sectional view of an inner tube.
FIG. 5 is an enlarged cross-sectional view taken along line VV in FIG. 1;
6 is a cross-sectional view taken along line VI-VI in FIG.
FIG. 7 is an enlarged cross-sectional view of a connecting portion between a rod cover, a head cover, and a cylinder tube.
8 is a cross-sectional view taken along line VIII-VIII in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cylinder tube 10 Head cover 13 Piston 16 Piston rod 17 Clamper 35 Head cover main body 36 Cap 36a Cap center hole 52 Turning rod 55 Turning groove 56 Intermediate member 57 Accommodating hole 58 Ball holder part 61 Intermediate member center hole 62 Guide ball (guide) Element)
63 Rotating motion generating mechanism 65 Clutch mechanism 67 V groove (engagement / removal recess / engagement groove)
68 Engaging ball
69 Spring (Biasing member)
W Work

Claims (4)

When the piston moves in the axial direction in the cylinder tube, the piston rod turns and moves in the axial direction through a turning motion generating mechanism including a turning groove and a guide member guided by the turning groove. In the revolving clamp cylinder in which the clamper integrated with the clamp clamps the workpiece, the revolving rod is projected integrally from the piston to the rear, and the revolving rod is pivotable with respect to the cylinder tube. fitted, one of turning groove and the guide member to the turning operation rod, and the guide member to the turning groove in Rukoto provided the other to the intermediate member engaged usher constitutes a turning motion generating mechanism, the intermediate member and the cylinder tube between the intermediate member cylinder tube integrally coupled Suruga until turning torque acting on the intermediate member is the allowable torque, the allowable torque The pivoting clamp cylinder the intermediate member to release the coupling between the intermediate member and the cylinder tube, characterized in that is interposed configured clutch structure to pivot when exceeded. A piston and a piston rod are integrally formed, and the turning rod is fitted into a center hole of an intermediate member provided to be rotatable with respect to a head cover that closes one end of the cylinder tube , and the turning groove and the guide member are inserted into the turning rod. One of the two is provided with the other remaining on the intermediate member to form a turning motion generating mechanism. Between the intermediate member and the head cover, the engaging / disengaging member and the engaging / disengaging recess for engaging / disengaging the engaging / disengaging member are disposed. 2. A swing type clamp cylinder according to claim 1, wherein a clutch structure having an urging member for meshing the member and the engagement / disengagement groove is interposed.   The intermediate member is movable in the axial direction by a predetermined amount with respect to the head cover, and an engaging / disengaging groove is provided on one end surface of the intermediate member in the axial direction and one end of the head cover portion facing the end surface in the axial direction, and an engaging / disengaging ball on the other. The swing clamp cylinder according to claim 2, wherein the clutch member is configured by urging the intermediate member with an urging member in a direction in which the engagement / disengagement groove and the engagement / disengagement ball are engaged.   The head cover is composed of a head cover main body formed with an accommodation hole for the intermediate member facing the piston rod side, and a cap for closing the accommodation hole, and the stepped intermediate member is axially and circumferentially arranged in the accommodation hole. The ball holder portion of the intermediate member is movably accommodated and protrudes from the center hole of the cap to hold the guide ball and engage with the turning groove of the turning rod, and the intermediate member is provided with an engagement / disengagement ball on the cap side end surface, A radial V-groove is formed in an inner end face of the cap facing the engagement / disengagement ball, and a spring for biasing the intermediate member forward in the axial direction is interposed between the receiving hole bottom surface of the head cover body and the intermediate member. 3. A swiveling clamp cylinder according to 3.

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