WO2005052383A1

WO2005052383A1 - Fluid pressure cylinder

Info

Publication number: WO2005052383A1
Application number: PCT/JP2004/017498
Authority: WO
Inventors: Akio Nakata; Masakazu Tetsuka; Hirotaka Kakae
Original assignee: Koganei Corporation; Daihatsu Motor Co., Ltd.
Priority date: 2003-11-27
Filing date: 2004-11-25
Publication date: 2005-06-09
Also published as: JP4241344B2; JP2005155837A

Abstract

A lock unit housing (13) in which two lock units (29, 129) are assembled inverted to each other is attached to a drive cylinder (12) where a piston rod (14) is assembled, and the piston rod (14) projects to the outside from the head of the lock unit housing (13). Each of the lock units (29, 129) has a retainer (37) for receiving steel balls (36) and a lock sleeve (38) provided outside the retainer. On the lock unit housing (13) are installed lock cylinders (17, 117) for driving fastening rods (45, 145). The fastening rods (45, 145) drive the corresponding lock sleeves (38) into a fastened state and a fastening-released state. To fix the piston rod (14), one (45) of the fastening rods drives the lock sleeve (38) into a fastened state prior to driving the other fastening rod (145).

Description

Specification

Fluid pressure cylinder technical field

The present invention relates to a hydraulic cylinder that reciprocates a piston rod by a fluid pressure such as air pressure, and more particularly to a technology effective when applied to a hydraulic cylinder having a lock mechanism.

Background art

[0002] An assembly line of an automobile is provided with a plurality of steps of joining panel materials formed in a pressing step by spot welding or the like. These processes include an underbody process that forms the base of the vehicle body, a side body process that forms the side surface of the vehicle body, a main body process that forms the skeleton of the vehicle body by joining the underbody and the side body, There is a metal line process for assembling doors and hoods on the body.

[0003] As a method of moving a panel material between work stages for performing various processes on an automobile assembly line, a panel material is fixed to an end of a transfer actuator such as a robot arm by an insertion clamp or the like. In many cases, a handling device is installed and the paneling material is moved together with the fixed binding device by operating the arm.

[0004] In addition, a cylinder ring actuator for moving each insertion clamp forward and backward so as to be able to fix each of various types of members having different shapes is installed in the case of a cylinder ring apparatus. Many hydraulic cylinders that use air pressure are used for the user so that even if the insertion clamp collides with the panel material, the impact can be absorbed. Disclosure of the invention

Problems to be solved by the invention

[0005] The locking mechanism provided in the above-mentioned fluid pressure cylinder while applying force only has a configuration that locks only movement of the piston rod in one of the forward direction and the backward direction. Therefore, even if the fluid cylinder is extended and the insertion clamp is pushed into the panel material and inserted and fixed, and the piston rod position is locked at that time, even if the panel material is moved together with the handling device by driving the robot arm, Piston rod moves to lock position As a result, the fixing position of the panel material was shifted, so that accurate positioning of the panel material was not possible, and it was difficult to perform assembly work with high accuracy!

[0006] An object of the present invention is to provide a fluid pressure cylinder capable of applying a braking force to an axial position of a piston rod in both forward and backward directions.

Means for solving the problem

[0007] A fluid pressure cylinder according to the present invention includes a drive cylinder in which a piston rod having a main piston is reciprocally accommodated in an axial direction and is provided with a forward pressure chamber and a retreat pressure chamber defined by the main piston. A first lock unit having a first lock sleeve that is installed in a unit housing chamber of a lock unit housing attached to the drive cylinder and that fastens the piston rod, and is installed in the unit housing chamber; A second lock unit having a second lock sleeve for fastening a piston port; and a lock unit, which is attached to a housing and contacts a first inclined surface formed on the first lock sleeve. A fastening position having a first pressing surface and approaching the piston rod, and a fastening release position away from the piston rod A first lock cylinder accommodating a first fastening rod that is reciprocally movable between the first lock cylinder and a second inclined surface formed on the second lock sleeve, the second lock sleeve being attached to the lock unit housing; A second lock cylinder that has a second pressing surface and accommodates a second fastening rod that is reciprocally movable between a fastening position approaching the piston rod and a fastening release position away from the piston rod. It is characterized by.

[0008] A fluid pressure cylinder according to the present invention is characterized in that the first and second lock sleeves are installed so that the first and second inclined surfaces face each other.

[0009] In the fluid pressure cylinder of the present invention, the first lock sleeve has a first inner peripheral surface having a tapered shape, and the first lock unit includes a plurality of first inner peripheral surfaces that are in contact with the first inner peripheral surface. A first retainer that holds the steel ball and is movably fitted in the piston rod in the axial direction, and presses the steel ball against the first inner peripheral surface via the first retainer. A first spring member for applying a spring force in a direction, and the second lock sleeve has a tapered second inner peripheral surface that is opposite to the first inner peripheral surface. The second lock unit holds a plurality of steel balls in contact with the second inner peripheral surface, and a second retainer fitted to the piston rod so as to be movable in the axial direction; Hold the steel ball through the cage And a second spring member for applying a spring force in a direction of pressing the second inner peripheral surface.

[0010] In the fluid pressure cylinder according to the present invention, the first and second lock cylinders each include a spring member that reduces a spring force in a direction toward the piston rod with respect to each of the fastening rods. It is characterized by.

[0011] In the fluid pressure cylinder according to the present invention, a restrictor for communicating the unit storage chamber and the retreat pressure chamber is provided on a partition wall that partitions the unit storage chamber and the retreat pressure chamber, and a fluid pressure source is provided. A supply / discharge port connected via a retreat channel is communicated with the unit housing chamber, and supply and discharge of fluid to and from the retreat pressure chamber are performed via the unit housing chamber. I do.

[0012] In the fluid pressure cylinder of the present invention, a check valve for allowing the flow of the fluid toward the unit housing chamber and preventing the flow of the fluid in the opposite direction is provided on the partition wall. It is characterized by

[0013] In the fluid pressure cylinder according to the present invention, the first fastening rod is separated from the piston rod by a lock pressure chamber that applies a thrust to the first fastening rod in a direction toward the piston rod. A first lock piston for partitioning the inside of the first lock cylinder and a lock release pressure chamber for applying a thrust force in the first direction, wherein the second fastening rod is connected to the piston rod with respect to the second fastening rod. A second lock piston for partitioning the inside of the second lock cylinder into a lock pressure chamber for reducing the thrust in a heading direction and a lock release pressure chamber for applying a thrust in a direction away from the piston rod force; It is characterized by.

[0014] In the fluid pressure cylinder according to the present invention, a fluid pressure source is connected to a supply / discharge port communicating with the first lock pressure chamber by a fluid introduction path, and the first lock pressure chamber and the second lock pressure are connected to each other. And the chamber are connected in series by a fluid communication passage, and the fluid from the fluid pressure source to the second lock pressure chamber is supplied through the first lock pressure chamber.

[0015] The fluid pressure cylinder of the present invention has a through hole communicating with the supply / discharge port, and fits movably in the axial direction into a receiving hole formed in the first fastening rod. A plunger having a piston part is incorporated into the first fastening rod, and when the first fastening rod moves a predetermined stroke toward the piston rod, the fluid introduction path and the fluid introduction path are connected to each other. It is characterized by communicating with the first lock pressure chamber.

[0016] The fluid pressure cylinder according to the present invention is characterized in that the first fastening rod applies a pressing force to the first lock sleeve toward the tip of the piston rod.

The invention's effect

According to the present invention, two sets of lock units each having a lock sleeve operated by a fastening rod are provided in the lock unit housing, and the two lock units are opposite to each other. The piston rod can be fixed by increasing the braking force or the fastening force in both the forward and backward directions. Since the strain forces stored in the two lock units are stored so as to cancel each other in the opposite directions, the piston rod is reliably applied to the piston rod even if external force is applied in either the forward or backward direction. Can be fixed.

[0018] Since the two lock units operate so as to switch between fastening to and releasing from the piston rod by moving the fastening rod forward and backward, the piston rod can be fastened and fixed at an arbitrary axial position.

[0019] Since the two lock units are switched to the engaged state using the thrust of the lock fluid in the lock pressure chamber and the thrust of the lock spring member, the lock can be performed without reducing the engagement force of the lock unit. The spring force from the use spring member can be set low. Since the two mouth pressure chambers are connected in series via the lock fluid supply path and are supplied with fluid in order, a time lag can be provided for the fastening operation of the two lock units, and Play can be removed in order.

[0020] Since the retraction pressure chamber is connected to the unit accommodating chamber through a tick valve and a throttle arranged in parallel, the two lock units are engaged when the piston rod starts retreating. Can be canceled. When the backward movement of the piston rod is restricted, the two lock units are switched to the fastening state, so that the axial position of the piston rod can be reliably fixed in both the forward and backward directions.

[0021] The thrust by the fluid in the lock pressure chamber and the spring force of the lock spring member are applied to the piston rod in the axial direction via the locked lock unit, so that the lock unit can store a distortion force. it can. [0022] Between the fastening rod and the lock sleeve that reciprocate in a direction orthogonal to each other, the thrust of the fastening rod is transmitted to the lock sleeve by sliding contact between the pressing surface and the inclined surface, so that the fastening operation can be performed smoothly and reliably. it can. The ball placed on the outer peripheral surface of the piston rod is pressed against the outer peripheral surface of the piston rod by the lock sleeve mounted reciprocally in the axial direction of the piston port, and the lock unit is fastened. And it can be securely tightened.

Brief Description of Drawings

FIG. 1 is a diagram showing a part of a vehicle body assembly line in which a robot arm provided with a handling device conveys a panel material constituting a vehicle body.

[FIG. 2] (A) is a plan view showing the fluid pressure cylinder of the first embodiment, (B) is a right side view of FIG. 2 (A), and (C) is a left side view of FIG. 2 (A). It is.

FIG. 3 is a longitudinal sectional view of the fluid pressure cylinder taken along line XX in FIG. 2 (A).

FIG. 4 is a circuit diagram showing a fluid pressure circuit for supplying compressed air to a drive cylinder and two lock cylinders.

[FIG. 5] (A) is a cross-sectional view showing the lock cylinder in which the fastening rod is in an unlocked state, and (B) is a cross-sectional view showing the lock cylinder in a state in which the fastening rod is moving forward. .

FIG. 6 (A) is a cross-sectional view showing the lock cylinder in a state where the fastening rod has moved forward and the fluid of the fluid pressure source has flowed into the lock pressure chamber. FIG. 4 is a sectional view showing the lock cylinder in a moved state.

FIG. 7 is a longitudinal sectional view of a fluid pressure cylinder according to another embodiment of the present invention.

FIG. 8 is a longitudinal sectional view of a fluid pressure cylinder according to still another embodiment of the present invention.

9 is a circuit diagram showing a fluid pressure circuit for supplying compressed air to the drive cylinder and two lock cylinders shown in FIG.

FIG. 10 is a circuit diagram showing a modification of the fluid pressure circuit shown in FIGS. 4 and 9.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of an industrial robot 1 equipped with a handling device. FIG. 3 is a view showing a part of a vehicle body assembly line configured to transport a flannel material. The industrial robot 1 has a plurality of arms 2 connected by joints 3, and a handling device 4 is attached to a tip of the arm 2. The handling device 4 has a pedestal 5 that can be attached to the tip of the arm, and a plurality of insertion clamps 6 are provided on the pedestal 5 to insert the locking pins into the fixing holes of the panel material W to fix the panel material W. Some of the insertion clamps 6 can be moved forward and backward by the fluid pressure cylinder 11. By moving the insertion clamps 6 forward and backward as described above, various types of panel materials W having mutually different shapes can be fixed and transported by one handling device 4.

[0026] The industrial robot 1, for example, grasps the panel material W supported and transported by the transport trolley, transports it to the welding stage, and returns to the transport trolley again after welding work on the panel material is completed. It is used. When grasping the panel material W with the handling device 4 of the industrial robot 1, the hydraulic cylinder 11 is retracted and all the insertion clamps 6 are positioned at the retracted position. Move the insertion clamp 6 forward in the order of the fixing hole force of the panel material W on the near side and insert it. When inserting each insertion clamp 6 by extending the fluid pressure cylinder 11, insert the clamp 6 when the cylinder stopper 7 provided on the fluid pressure cylinder 11 comes into contact with the stage stopper 8 provided on the stage side. To stop the forward movement. In FIG. 1, two insertion clamps 6 are provided in the handling device 4 and one of them is installed so as to be able to move forward and backward by the hydraulic cylinder 11, but it is optional depending on the size and shape of the panel material W. The number of insertion clamps provided in the ring ring device 4 can be moved forward and backward by the hydraulic cylinder 11.

As shown in FIG. 2, the fluid pressure cylinder 11 includes a drive cylinder 12 having a substantially quadrangular prism shape, and a substantially rectangular parallelepiped lock unit No. 13 mounted on one end of the drive cylinder 12. The piston rod 14 mounted on the drive cylinder 12 and thereby reciprocally movable in the axial direction penetrates through the lock unit housing 13, and the tip force of the lock unit housing 13 also protrudes to the outside. A connecting plate 16 is attached to the two guide rods 15 and the piston rods 14 which reciprocately penetrate the lock unit nosing 13 in parallel with the piston rods 14, and these rods 14, 15 They are connected by a connection plate 16. The lock unit housing 13 has the first The second two lock cylinders 17, 117 are mounted. As shown in FIG. 2 (A), the lock unit housing 13 has a screw hole 19 for mounting the fluid pressure cylinder 11 to the above-described handling device 4.

The fluid pressure cylinder 11 moves the piston rod 14 forward and backward by supplying compressed air to one of the two supply / discharge ports 20, 21 formed in the drive cylinder 12 and discharging the compressed air to the other. Let it. The piston rod 14 is fixed by supplying compressed air to a supply / discharge port 61 formed in the lock unit housing 13.

As shown in FIG. 3, a piston housing hole 24 for housing a main piston 23 fixed to the piston rod 14 so as to be able to reciprocate in the axial direction is formed in the drive cylinder 12, and the lock unit housing 13 and the piston The housing hole 24 is partitioned by a partition wall 25 attached to one end of the drive cylinder 12. A head cover 26 is fixed to the other end of the drive cylinder 12, and the piston receiving hole 24 is closed. The internal space of the piston receiving hole 24 closed by the partition wall 25 and the head cover 26 forms a cylinder chamber 28.

The lock unit housing 13 is formed with a mouthpiece housing hole 30 for housing the two lock units 29 and 129, and a rod cover for closing the lock unit housing hole 30 is provided at the end of the lock unit housing 13. 31 is installed. A unit housing chamber 33 is formed by the lock unit housing hole 30 closed by the rod cover 31 and the partition wall 25, and a distal end portion of the piston rod 14 projects from the rod cover 31 to the outside. A cylinder body is formed by the drive cylinder 12, the lock unit housing 13, and the two lock cylinders 17, 117.

The interior of the cylinder chamber 28 is divided into a forward pressure chamber 34 and a reverse pressure chamber 35 by a main piston 23 accommodated in the drive cylinder 12. The drive cylinder 12 is formed with a forward supply / discharge port 20 and a reverse supply / discharge port 21. The forward supply / discharge port 20 communicates with the forward pressure chamber 34, and the reverse supply / discharge port 21 is connected to the lock unit. In addition, it communicates with the unit accommodation room 33 via the supply / discharge passage 22 in the housing 13. A check valve 59 and a throttle 60 are provided on the partition wall 25.The check valve 59 allows the flow of air from the retreat pressure chamber 35 to the unit storage chamber 33, and blocks the flow in the reverse direction, thus restricting the flow. 60 communicates the retreat pressure chamber 35 with the unit accommodation chamber 33. Thus, the retraction pressure chamber 35 communicates with the unit accommodation chamber 33. When compressed air, which is a fluid, is supplied to the forward pressure chamber 34 from the forward supply / discharge port 20, the main piston 23 is pressed by the compressed air and moves forward toward the partition wall 25, and the backward pressure chamber is moved. The air in 35 flows into the unit housing chamber 33 through the check valve 59 and the throttle 60, and is discharged from the supply / discharge port 21. On the other hand, when compressed air is supplied to the retraction supply / discharge port 21, the compressed air is supplied to the retraction pressure chamber 35 via the throttle 60 while increasing the pressure in the unit storage chamber 33, and the main piston 23 is moved to the head cover 26. Retreat toward.

[0032] The main piston 23 has an annular first disk 23a provided with a sealing material 23c and a second disk 23b, and an external thread 14a of the piston rod 14 is provided on an inner peripheral surface of the first disk 23a. A female screw 23e to be screwed is formed. An annular magnet 23f is interposed between the first disk 23a and the second disk 23b, and a sensor (not shown) provided on the drive cylinder 12 responds to the magnetic force of the magnet 23f, thereby causing the main piston 23f to move. Position can be detected.

[0033] In the unit accommodating chamber 33, first and second two lock units 29, 129 are installed in the axial direction and opposite to each other, and the first lock unit 29 is provided with a rod cover 31. The second lock unit 129 is adjacent to the partition wall 25. Each of the lock units 29 and 129 holds a plurality of steel balls 36 arranged in contact with the outer peripheral surface of the piston rod 14, and holds the plurality of steel balls 36 and moves in the axial direction relative to the piston rod 14. And a cylindrical retainer 37 movably fitted. A lock sleeve 38 having a tapered inner peripheral surface 38a is disposed outside each of the retainers 37. The lock sleeve 38 is reciprocally housed in the lock unit housing hole 30. I have. As described above, a plurality of steel balls 36 are disposed between the outer peripheral surface of the piston rod 14 and the inner peripheral surface 38a of the lock sleeve 38, and the lock unit 29 is moved by moving the lock sleeve 38 in the axial direction. , 129 are switched between a fastening state in which the lock sleeve 38 presses the steel ball 36 against the piston rod 14 to fix the piston rod 14 and a release state in which the pressing on the piston rod 14 is released to release the fastening.

[0034] Between the respective lock sleeves 38 and the partition wall 25 and between the rod cover 31, a bottomed cylindrical spring receiving member 39 having a flange portion 39a is provided. Between the flange portion 39a of each spring receiving member 39 and the partition wall 25 and between the rod cover 31 A release spring member 40 is provided between them. The release spring member 40 applies a spring force to the lock sleeve 38 in the release direction via a flange portion 39a that contacts the lock sleeve 38. That is, each release spring member 40 urges the lock sleeve 38 in a direction away from the partition wall 25 and the rod cover 31. Further, a holding spring member 41 is provided between the bottom of the spring receiving member 39 and the holder 37, and these holding spring members 41 are arranged so that the respective holders 37 are moved in the direction of approaching each other. Apply force.

The lock unit housing 13 is provided with stoppers 13a protruding into the unit accommodating chamber 33, and a cylindrical positioning sleeve 42 is provided between each retainer 37 and the stopper 13a. It is mounted on the outside of the housing so as to be able to reciprocate in the axial direction relatively to this. Both ends of the positioning sleeve 42 abut the stopper 13a and the respective retainer 37, thereby regulating the position of each lock sleeve 38 when the two lock sleeves 38 approach each other.

As shown in FIG. 4, each of the two lock cylinders 17 and 117 is formed by a cylinder portion 43 and a head cover 44 that closes the cylinder portion. Fastening rods 45, 145 are housed in the respective lock cylinders 17, 117, and both fastening rods 45, 145 are reciprocally movable in the radial direction with respect to the bistro rod 14. An annular lock piston 45a is provided on the fastening rods 45 and 145, and a thrust of a lock pressure chamber 47 for accommodating a lock spring member 46 and a lock spring member 46 is provided in the cylinder portion 43 from the lock piston 45a. A lock release pressure chamber 48 is provided which locks the thrust of the fluid to the fastening rods 45 and 145 in opposition to the spring force.

[0037] The lock piston 45a is provided at the base end of the fastening rods 45 and 145, and has a spring accommodating hole 45b and a cylinder hole 45c therein. An annular spring receiving member 49 is incorporated in the spring receiving hole 45b, and a locking spring member 46 is held between the spring receiving member 49 and the head cover 44. A plunger 50 having a piston portion 50a and a rod portion 50b is incorporated in a cylinder hole 45c of a fastening rod 45 accommodated in one lock cylinder 17 so as to be reciprocally movable. A plunger spring member 51 is incorporated between the bottom of the cylinder hole 45c and the bottom. The spring force of the plunger spring member 51 applies a spring force to the plunger 50 in a direction approaching the head cover 44, and the plunger 50 moves in this direction. The movement is regulated by the contact of the piston portion 50a with the spring receiving member 49. That is, the spring receiving member 49 of the mouth cylinder 17 also functions as a stopper for restricting the axial movement of the plunger 50 with a predetermined stroke.

As shown in FIG. 4, fluid introduction holes 52 and 152 for guiding compressed air, which is a lock fluid, to the lock pressure chamber 47 are formed substantially in the center of the head cover 44 of each of the lock cylinders 17 and 117. In addition, a fluid discharge hole 53 for discharging compressed air from the lock pressure chamber 47 is formed in the head cover 44 of the lock cylinder 17.

As shown in FIG. 4, the fluid introduction hole 52 and the plunger 50 are substantially concentrically assembled, and the plunger 50 moves upward (in a direction away from the piston rod 14) in the figure, whereby the plunger 50 is moved. Upon contact with 44, the fluid introduction hole 52 and the lock pressure chamber 47 are shut off by the rod portion 50b of the plunger 50. On the other hand, when the fastening port 45 moves downward in the drawing (in a direction approaching the piston rod 14) and the plunger 50 moves away from the head cover 44, the fluid introduction hole 52 and the lock pressure chamber 47 communicate with each other. State. A valve seat 54 is incorporated in the opening of the fluid introduction hole 52 formed in the head cover 44, and the airtightness in the shut-off state is established by bringing the end face of the rod portion 50b of the plunger 50 into contact with the valve seat 54. Will be kept.

[0040] Each of the unlocking pressure chambers 48 communicates with the unit housing chamber 33 via a communication passage 55, and when compressed air is supplied from the unit housing chamber 33 to the unlocking pressure chamber 48, the fastening rods 45, 145 are connected. Moves upward toward the retreat position away from the piston rod 14. In particular, during the upward movement of the fastening rod 45 in the lock cylinder 17, the rod portion 50b of the plunger 50 projects from the end surface of the lock piston 45a until the lock piston 45a contacts the head cover 44. After the portion 50b contacts the valve seat 54 of the head cover 44, the lock piston 45a contacts the head cover 44. When the fastening rod 45 moves upward until the lock piston 45a contacts the head cover 44, a predetermined clearance C1 is formed between the piston portion 50a and the spring receiving member 49 as shown in FIG.

When the two fastening rods 45 and 145 are respectively moved upward, the air in the lock pressure chamber 47 is exhausted through the fluid introduction holes 52 and 152. In the rod 45, the fluid introduction hole 52 is closed when the rod portion 50b of the plunger 50 contacts the valve seat 54. For this reason, the U packing 56 provided in the piston portion 50a is mounted in a direction that allows air flow in the downward direction, and the air in the lock pressure chamber 47 is released after the rod portion 50b and the valve seat 54 come into contact with each other. However, air can be discharged in the downward direction from between the U packing 56 and the cylinder hole 45c, and is exhausted from the fluid introduction hole 52 through the through hole 50c formed at the center of the plunger 50. can do.

On the other hand, when the compressed air in each unlocking pressure chamber 48 is discharged through the communication passage 55, the fastening ports 45, 145 approach the piston rod 14 by the spring force from the locking spring member 46, and And moves downward to the operating position where it contacts the sleeve 38. In the process of moving the fastening rod 45 having the plunger 50 downward, the plunger 50 is urged in the ascending direction by the spring force, so that the piston portion 50a of the plunger 50 is released after the lock piston 45a is also separated from the head cover 44. The rod portion 50b separates from the head cover 44 after coming into contact with the spring receiving member 49. That is, even if the fastening rod 45 starts descending movement, the rod part 50b keeps the state in contact with the valve seat 54 of the head cover 44 until it descends by a predetermined stroke corresponding to the clearance C1.

At the tip of each of the fastening rods 45 and 145, a taper portion 45e having a lock taper surface 45d as a pressing surface is formed, and the taper angle of the lock taper surface 45d is an acute angle of about 30 °. Is formed. In order to correspond to these lock taper surfaces 45d, tapered surfaces 38b, which are inclined surfaces, are also formed on the end faces of the two lock sleeves 38 facing each other, and the taper angle of the tapered surface 38b is approximately It is formed at an obtuse angle of 150 °. When each of the fastening rods 45, 145 moves downward toward the lock sleeve 38, the tapered surface 45d of the fastening rod 45 in the lock cylinder 17 becomes the tapered surface (inclined surface) 38b of the right lock sleeve 38 in FIGS. Then, the tapered surface 45 d of the fastening rod 145 of the lock cylinder 117 comes into contact with the tapered surface 38 b (inclined surface) of the left lock sleeve 38. As a result, the respective lock sleeves 38 are pushed in directions away from each other, and the two lock units 29, 129 are brought into the fastening state. On the other hand, when the fastening rods 45 and 145 move upward, the respective lock sleeves 38 are pushed in directions approaching each other by the spring force of the release spring member 40, and the two lock units 29 and 129 are released. [0044] The through hole 50c of the plunger 50 is used not only for discharging the air in the lock pressure chamber 47 but also for manually moving the fastening rod 45. The fluid introduction holes 52, 152 formed in the head cover 44 are provided with screw members 57 as plugs for shutting off the fluid introduction holes 52, 152 from the outside, and the fastening rods 45, 145 have cylinder holes 45c. And a screw hole 45f is formed. When manually moving the fastening rods 45 and 145, it is not shown that a male screw is formed at the tip end.The rod member is inserted into the fluid introduction holes 52 and 152 from the outside with the screw member 57 removed, Screw it to screw hole 45f. Thereby, the fastening rods 45, 145 can be moved up and down from outside via the rod members.

As shown in FIG. 3, an annular rubber damper 23d is attached to the main piston 23. Even when the main piston 23 is in contact with the head cover 26 or the partition wall 25, the rubber damper 23d is provided. A gap is formed on the outer periphery. The forward supply / discharge port 20 communicating with the forward pressure chamber 34 is formed so as to communicate with the forward pressure chamber 34, and the throttle 60 communicating with the backward pressure chamber 35 is connected to the backward pressure chamber 35. It is formed to pass through. Each of the supply / discharge ports 20, 21 is connected to a compressed air source through a common flow path switching valve described later, and one of the two supply / discharge ports 20, 21 is operated by switching operation of the flow path switching valve. And compressed air is discharged from the other supply / discharge ports 20, 21. Therefore, it is possible to control the supply and discharge of the compressed air to the forward pressure chamber 34 and the backward pressure chamber 35 through the respective supply / discharge ports 20 and 21.

[0046] The through hole 25a of the partition wall 25 through which the piston rod 14 penetrates has substantially the same diameter as the outer diameter of the piston rod 14, and the sealing material 25b attached to the inner peripheral surface thereof contacts the outer periphery of the piston rod 14. are doing. Since a communication gap 58 is formed between the retainer 37, the positioning sleeve 42, and the spring receiving member 39 with the outer peripheral surface of the piston rod 14, the retreating supply / discharge port 21 communicates with the unit storage chamber 33. It communicates with the unlocking pressure chamber 48 in each of the lock cylinders 17 and 117 via each communication passage 55. The retraction supply / discharge port 21 also communicates with the retraction pressure chamber 35 via the unit accommodation chamber 33 and the throttle 60. Thus, each lock release pressure chamber 48 communicates with the retraction supply / discharge port 21 and the retraction pressure chamber 35, respectively. When compressed air is supplied to the retraction supply / discharge port 21, the compressed air supplied to the unit storage chamber 33 does not flow into the retraction pressure chamber 35 via the check valve 59 of the partition wall 25. It will be introduced through the squeeze 60. Since the throttle 60 has a small flow passage cross-sectional area and a small allowable passage flow rate, a back pressure is generated inside the unit accommodation chamber 33, and the pressure rises. For this reason, the pressure in the unlocking pressure chamber 48 in each of the lock cylinders 17 and 117 increases through the communication passage 55 before the pressure chamber 35 for retreating, and the fastening rods 45 and 145 are raised to the retreat position. Will be. Thereafter, the compressed air is sufficiently introduced into the retreat pressure chamber 35, and the main piston 23 is moved in the retreat direction. When compressed air is supplied to the retraction supply / discharge port 21 in this manner, the main piston 23 retreats after the fastening rods 45 and 145 have moved to the retreat position.

As shown in FIG. 4, a compressed air source 65 such as a compressor is connected to the input port 66 a of the flow path switching valve 66, and a forward fluid flow path 67 connected to the forward supply / discharge port 20 and a reverse supply A retreating fluid flow path 68 connected to the discharge port 21 is connected to the two output ports 66b and 66c of the flow path switching valve 66, respectively. The forward fluid flow path 67 is provided with a check valve 67a that allows the flow of air from the flow path switching valve 66 to the forward supply / discharge port 20 and prevents the flow in the reverse direction. The aperture 67b is connected in parallel with the.

The lock supply / discharge port 61 is connected via a lock fluid flow path 69 to a forward fluid flow path 67 on the flow path switching valve 66 side from the check valve 67a. By switching between the two switching positions, the flow path switching valve 66 connects one of the forward fluid path 67 and the backward fluid path 68 to the compressed air source 65 to supply compressed air, and supplies the other. Release to the outside air to discharge compressed air.

[0050] Compressed air (lock fluid) supplied through a supply / discharge port 61 formed in the lock unit housing 13 is supplied to a fluid introduction hole 52 of the lock cylinder 17 through a fluid introduction path 62 shown in FIG. Supplied. The fluid discharge hole 53 formed in the head cover 44 of the lock cylinder 17 communicates with the fluid introduction hole 152 of the lock cylinder 117 via the fluid communication channel 63, and compressed air is supplied through the lock pressure chamber 47 of the lock cylinder 17 It is now being done. As described above, when the compressed air is supplied to the supply / discharge port 61, the compressed air is supplied to the lock pressure chamber 47 in the lock cylinder 17 via the fluid introduction path 62, and the fastening rod 45 is moved down to the operation position, Further, compressed air is supplied from the lock pressure chamber 47 in the lock cylinder 17 to the lock pressure chamber 47 in the lock cylinder 117 via the fluid communication path 63, and the fastening rod 145 moves down to the operating position.

Next, with reference to FIGS. 5 and 6, the operation of the fastening rod 45 when the piston rod 14 is moved forward from the state in which the piston rod 14 is retracted into the drive cylinder 12 as shown in FIG. 3 will be described with reference to FIGS. explain.

When the piston rod 14 is at the retreat limit position, compressed air is supplied from the retreat supply / discharge port 21 to the unit housing chamber 33 and the unlocking pressure chamber 48. A pressing force is applied to the fastening rod 45 in the upward direction for compressing the locking spring member 46 by the compressed air collected in the unlocking pressure chamber 48, and the fastening rod 45 is lifted away from the lock sleeve 38. ing. The pressure receiving area of the lock piston 45a is set to a sufficient area to generate a pressing force against the spring force from the locking spring member 46.

When the fastening rod 45 moves upward, the contact between the fastening rod 45 and the lock sleeve 38 is avoided, so that the lock sleeve 38 moves backward toward the release position by the spring force of the release spring member 40. Under the retracted state, a predetermined clearance C2 is formed between the end face of the lock sleeve 38 and the end face of the rod cover 31 as shown in FIG. As described above, when the lock sleeve 38 operates to the release position, a predetermined clearance C3 is provided between the inner peripheral surface 38a of the lock sleeve 38 and the steel ball 36. It is in a released state where it is not pressed by the rod 14.

In this state, when compressed air is supplied from the forward supply / discharge port 20 to the forward pressure chamber 34 and the compressed air is discharged from the backward pressure chamber 35, the main piston 23 and the piston rod 14 is moved in the forward direction indicated by the arrow a in FIG. At this time, the air in the retreat pressure chamber 35 flows into the unit housing chamber 33 through the check valve 59 and the throttle 60 with the movement of the main piston 23, and the retreat supply / discharge port 21 The fluid is further discharged to the retreating fluid channel 68. At the same time, the air in the unit storage chamber 33 is compressed by the throttle 68b provided in the retreating fluid flow channel 68, and the pressure increases. That is, the back pressure (lock release fluid) corresponding to the moving speed of the main piston 23 is stored in the unit accommodation room 33. Pressure).

Since the back pressure generated in the unit storage chamber 33 is applied to the unlocking pressure chamber 48 via the communication passage 55, a pressing force is applied to the fastening rod 45 in the upward direction for compressing the locking spring member 46. As a result, the fastening rod 45 is held at the retracted position. The pressure receiving area of the lock piston 45a that receives the back pressure generated in the unit housing chamber 33 is set to an area sufficient to generate a pressing force against the spring force from the locking spring member 46. That is, when the piston rod 14 is moved in the forward direction by supplying compressed air from the forward supply / discharge port 20 to the forward pressure chamber 34, the two lock units 29 and 129 are held in the released state. Therefore, the forward movement of the piston rod 14 becomes possible. As described above, when the piston rod 14 is moved forward and backward, the lock unit 29 can be released by the back pressure generated by the throttles 59 and 68a, and the piston rod 14 is allowed to move forward and backward. On the other hand, even if the piston rod 14 is moved backward in the direction of the arrow b by supplying compressed air to the retreat pressure chamber 35 and discharging compressed air in the forward pressure chamber 34, As described above, since the back pressure is applied to the unlocking pressure chamber 48 by the throttle 60, the lock unit 29 is released.

Next, the case where the piston rod 14 is at the forward limit position or the case where the forward movement of the piston rod 14 is limited and the main piston 23 stops will be described. First, when the compressed air source 65 is connected to the forward fluid channel 67 and the piston rod 14 is moving forward, compressed air is also supplied to the supply / discharge port 61 via the locking fluid channel 69. It will be. At this time, the fastening rod 45 moves upward to the retracted position in the fluid introduction hole 52 opened to the lock pressure chamber 47 under a state where the fluid introduction hole 52 and the lock pressure chamber 47 are shut off by the plunger 50. Thus, compressed air is supplied from the fluid introduction path 62. At this time, since the plunger 50 is provided with the through hole 50c, the plunger 50 does not receive the pressure of the compressed air from the fluid introduction hole 52 in the downward direction. The shut-off state is reliably maintained.

When the main piston 23 stops, the air in the unit storage chamber 33 is discharged from the flow path switching valve 66 without being compressed, so that the back pressure in the unit storage chamber 33 gradually decreases. Then, the spring force is applied to the lock piston 45a in opposition to the spring force from the lock spring member 46. As shown in Fig. 5 (B), when the pressing force for raising the lock piston 45a falls below a predetermined pressing force, the lock piston 45a is used for locking. It is urged in the downward direction by the spring force from the spring member 46, and moves downward while pushing the lock sleeve 38 toward the fastening position.

At this time, since the plunger 50 is urged in the ascending direction by the plunger spring member 51, the contact state between the rod portion 50b of the plunger 50 and the valve seat 54 even when the lock piston 45a starts moving downward. Is kept. That is, since the state of blocking between the fluid introduction path 62 and the lock pressure chamber 47 is continued, the fastening rod 45 is urged in the downward direction only by the spring force. The negative pressure is generated in the lock pressure chamber 47 by the downward movement of the lock piston 45a. The spring force of the lock spring member 46 is set so that the downward movement of the fastening rod 45 is continued against this negative pressure. ing.

The fastening rod 45 is moved downward by a predetermined stroke by the spring force of the locking spring member 46.

When the lock sleeve 38 moves at a predetermined stroke (for example, 0.8 mm) as the fastening rod 45 moves down, the lock sleeve 38 moves at a predetermined stroke (for example, 0.8 mm). As shown in FIG. 5 (B), when the lock sleeve 38 moves forward, the clearance C3 provided between the inner peripheral surface 38a of the lock sleeve 38 and the steel ball 36 is lost, and the outer peripheral surface of the piston rod 14 The steel ball 36 comes into contact with the inner peripheral surface 38a of the lock sleeve 38 to be sandwiched therebetween, and the fastening operation of the lock unit 29 is started.

As shown in FIG. 5 (B), when the downward movement of the fastening rod 45 reaches a predetermined stroke, the clearance C 1 formed between the piston portion 50a of the plunger 50 and the spring receiving member 49 Disappears, and the piston portion 50a and the spring receiving member 49 come into contact with each other. Subsequently, as shown in FIG. 6A, when the fastening rod 45 further moves down, the plunger 50 moves down together with the fastening rod 45. When the rod portion 50b of the plunger 50 is separated from the valve seat 54 by this downward movement, the fluid introduction hole 52 and the lock pressure chamber 47 are in communication with each other, and compressed air from the fluid introduction passage 62 is supplied to the lock pressure chamber 47. Is done. This operation does not require an external switching valve and operates automatically. In the state shown in FIG. 6 (A), in addition to the spring force from the lock spring member 46, a thrust by the compressed air (lock fluid) supplied to the lock pressure chamber 47 is applied to the fastening rod 45. As shown in FIG. 6B, when the fastening rod 45 to which the spring force of the locking spring member 46 and the thrust by the compressed air are further moved downward, the fastening rod 45 locks the connection plate 16. The sleeve 38 is pushed further in the forward direction. Then, when the clearance force between the lock sleeve 38 and the rod cover 31 is reduced to a predetermined clearance C4, that is, when the lock sleeve 38 is pushed to the fastening position, the steel ball 36 is connected to the lock sleeve 38. It is in a fastening state biting into the piston rod 14. As described above, when the mouth unit 29 is switched to the fastening state, the main piston 23 and the piston rod 14 are fixed at their stop positions. Further, when the lock unit 29 is switched to the fastening state, the piston rod 14, the steel ball 36 and the lock sleeve 38 are held in an elastically deformed state with respect to each other. Is stored.

[0062] Even if the lock unit 29 is switched to the engaged state, a predetermined clearance C4 is provided between the lock sleeve 38 and the rod force bar 31, so that the lock sleeve 38 is allowed to move further forward. Is done. The spring force from the lock spring member 46 and the thrust from the lock pressure chamber 47 transmitted to the lock sleeve 38 fastened to the piston rod 14 are applied to the piston rod 14 through the bow I and the lock sleeve 38. You will be able to move forward.

[0063] The spring force from the lock spring member 46 and the thrust force from the lock pressure chamber 47 are transmitted to the lock sleeve 38 via the lock taper surface 45d formed at an acute angle and the taper surface 38b formed at an obtuse angle. Therefore, the spring force from the lock spring member 46 and the thrust from the lock pressure chamber 47 are increased and transmitted to the piston rod 14. When the lock sleeve 38 moves to the fastening position, the taper rod portion 45e enters in the retreating direction of the lock sleeve 38, so that the lock unit 29 is securely fastened until compressed air is supplied to the unlock pressure chamber 48. The state can be maintained.

[0064] Even when the spring receiving member 39 moves forward with the movement of the lock sleeve 38, a retaining spring provided between the retainer 37 for retaining the steel ball 36 and the bottom of the spring receiving member 39. Since the retainer 37 can be kept in contact with the stopper 13a via the positioning sleeve 42 by the member 41, the position of the steel ball 36 can be securely locked without moving. The unit 29 can be switched to the fastening state.

In the above description, the case where the forward movement of the piston rod 14 is restricted and the main piston 23 stops has been described. However, the supply of the compressed air to the forward pressure chamber 34 is stopped so that the main piston 23 is stopped. Even in the case of stopping, the lock unit 29 can be similarly switched to the fastening state. In addition, even when the biston rod 14 is moved backward by pushing the connecting plate 16 or the like, the air in the unit housing chamber 33 is introduced into the retreat pressure chamber 35 to reduce the pressure in the unlocking pressure chamber 48. Thus, the mouthpiece 29 can be switched to the fastening state.

As described above, when the main piston 23 is stopped by restricting the movement of the piston rod 14 during the forward movement of the piston rod 14 or by stopping the supply of the compressed air to the forward pressure chamber 34, For example, when the pressure of the unit housing chamber 33 is reduced by pushing the connecting plate 16, the lock unit 29 is switched to the fastening state.

[0067] The lock unit 29 presses the steel ball 36 against the inner peripheral surface 38a of the lock sleeve 38 against the movement of the piston rod 14 in the retreating direction so that the fastening state can be more surely secured. When the piston rod 14 moves in the forward direction, there is a possibility that the steel ball 36 loses the restraining force of the lock sleeve 38 and loosens the fastening state.

However, the fluid pressure cylinder 11 of the present invention has the two lock units 29 and 129, and the fastening state is ensured even when the piston rod 14 moves in the forward direction. The inner peripheral surfaces 38a of the lock sleeves 38 of the lock units 29, 129 are opposite to each other, and the tapered surface 45d (pressing surface) of the fastening rod 45 is opposite to the tapered surface 3 of the lock unit 29. 8b (inclined surface) and the tapered surface 45d (pressing surface) of the fastening rod 145 comes into contact with the tapered surface 38b (inclined surface) of the other mouthpiece 129. Can be fixed in both the forward and backward directions, and the distortion forces stored in the two lock units 29 and 129 can be stored so as to cancel each other in the opposite directions. The axial position can be securely fastened and fixed in both forward and backward directions.

[0069] The two lock units 29, 129 fasten the piston rod 14 using the thrust of the compressed air in the lock pressure chamber 47 and the thrust of the lock spring member 46. The spring force from the locking spring member 46 can be set low without reducing the fastening force by the 129. As a result, the size and cost of the fluid pressure cylinder 11 can be reduced.

[0070] Since the two lock pressure chambers 47 are connected in series via a lock fluid supply path and are supplied with compressed air in order, when the piston rod 14 is fastened, the operation of the two fastening rods 45 and 145 is performed. A time lag can be provided between the two lock units 29 and 129, so that the play in each lock unit 29 and 129 can be removed better than in the case where the lock units 29 and 129 are operated simultaneously. In particular, in the present embodiment, since the lock unit 29 is operated first and then the lock unit 129 is operated, the forward movement of the piston rod 14 and the connection plate 16 is restricted as shown in FIG. The play in each lock unit 29, 129 can be best removed in the forward-restricted type of use mode in which the lock is fixed by the lock, and the lock can be securely performed. Further, by changing the length of the fluid communication passage 63 between the lock pressure chambers 47, the operation time difference can be changed.

[0071] The thrust by the compressed air in the lock pressure chamber 47 and the spring force of the lock spring member 46 are applied to the piston rod 14 in the axial direction via the lock units 29 and 129 in the engaged state. Units 29 and 129 can store distortion power. As a result, even after the compressed air is discharged from the lock pressure chamber 47, it is possible to maintain a high fastening force due to the distortion force and the spring force.

The supply and cutoff of the compressed air to the lock pressure chamber 47 are switched by the plunger 50 in accordance with the stroke of the fastening port 45, so that after the play of the lock unit 29 is removed, the inside of the lock pressure chamber 47 is removed. Strong thrust by the compressed air can be transmitted to the piston rod 14 via the lock unit 29. This makes it possible to store the distortion force in the lock unit 29 without wasting the stroke of the fastening rod 45. In the lock cylinder 117, the play of the lock units 29 and 129 can be eliminated at the same timing as the fastening rod 45 with the fastening rod 145, and then the fluid discharge hole 53 of the lock cylinder 17 and the fluid introduction hole of the lock cylinder 117. Since the compressed air is introduced into the 152, the supply and cutoff of the compressed air can be switched according to the stroke without providing the plunger 50.

When the fastening rod 45 moves upward to the retracted position, the push rod incorporated in the fastening rod 45 The lock pressure chamber 47 and the fluid introduction hole 52 are switched to the shut-off state by the lancer 50.On the other hand, when the fastening rod 45 moves down by a predetermined stroke, the lock pressure chamber 47 and the fluid introduction hole 52 are switched to the communication state. Can be Thus, even before the fastening rod 45 starts to move downward toward the operating position, compressed air can be supplied to the fluid introduction hole 52 in advance in preparation for switching the lock unit 29 to the fastening state. Pressure control can be increased. In addition, by incorporating the plunger 50 reciprocally with respect to the fastening rod 45, the compressed air is supplied to the lock pressure chamber 47 when the lock unit 29 is released without being affected by dimensional errors and assembly errors of each member. Can be reliably stopped. As a result, malfunction in the unlocked state of the lock unit 29 can be avoided.

FIG. 7 is a longitudinal sectional view of a fluid pressure cylinder according to another embodiment of the present invention. In FIG. 7, members common to the members shown in FIG. 3 are denoted by the same reference numerals. Have been. In the hydraulic cylinder 11 shown in FIG. 3, two lock cylinders 17 and 117 are mounted on the lock unit housing 13 in parallel on the same side, whereas the hydraulic cylinder 211 shown in FIG. The two lock cylinders 17 and 17 are attached to the lock unit housing 213 so as to oppose each other on the opposite side and overlap each other in the axial direction.

[0075] Also in the hydraulic cylinder 211 shown in Fig. 7, the fastening force can be applied to the axial position of the piston rod 14 in both the forward and backward directions. Furthermore, the two mouthpieces 29 and 129 can be made closer to each other, and the entire length of the fluid pressure cylinder 211 in the axial direction can be reduced. When the lock unit housing 213 having the unit accommodation chamber 233 has a cylindrical shape such as a cylinder, the two lock cylinders 17, 117 are not limited to the opposite sides but are shifted at any angle around the axis of the piston rod 14. It may be installed in an arrangement.

FIG. 8 is a longitudinal sectional view of a fluid pressure cylinder according to still another embodiment of the present invention. In FIG. 8, members common to those shown in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted.

[0077] The plunger 50 is incorporated in the left lock cylinder 117 of the two lock cylinders 17, 117 attached to the lock unit housing 313 of the fluid pressure cylinder 311 shown in FIG. Therefore, in this hydraulic cylinder 311, the lock cylinder 117 is tightened. The connecting rod 145 moves forward toward the piston rod 14 first, and when the backward movement of the piston rod 14 is restricted, a fastening force is applied to the piston rod 14 in both directions.

In the fluid pressure cylinder 311 shown in FIG. 8, since the partition wall 325 is not provided with a check valve or a throttle, the space between the retreat pressure chamber 35 and the unit storage chamber 33 is airtightly shut off. The retraction supply / discharge port 321 is formed so as to directly communicate only with the retraction pressure chamber 35. The lock unit housing 313 is provided with a release supply / discharge port 364 communicating with the unit storage chamber 33, and the supply / discharge port 364 is used to release the lock in each lock cylinder 17, 117 through the unit storage chamber 33. It communicates with the pressure chamber 48.

FIG. 9 is a circuit diagram showing a fluid pressure circuit for supplying compressed air to the drive cylinder and two lock cylinders shown in FIG. As shown in FIG. 9, a compressed air source 365 such as a compressor is connected to the input port 366a of the flow path switching valve 366, and the forward fluid flow path 367 connected to the forward supply / discharge port 20 and the reverse supply / discharge The retreating fluid flow path 368 connected to the port 21 is connected to the two output ports 366b and 366c of the flow path switching valve 366, respectively. At the respective intermediate positions of the forward fluid passage 367 and the backward fluid passage 368, the flow of air directed from the passage switching valve 366 to each of the supply / discharge ports 20 and 21 is allowed to allow the flow in the opposite direction. Check valves 367a and 368a are provided for blocking, and each check valve 367a and 368a is connected to a throttle 367b and 368b.

The lock supply / discharge port 61 is connected from the check valve 368a to the retraction fluid flow path 368 on the flow path switching valve 366 side via the lock fluid flow path 369, and the release supply / discharge port 364 is connected to the release flow path. The check valve 367a is connected to the forward fluid flow path 367 on the forward supply / discharge port 20 side via the body flow path 370.

The compressed air supplied via the lock supply / discharge port 61 is supplied to the fluid introduction hole 152 of the lock cylinder 117 via the fluid introduction path 362 shown in FIG. The fluid discharge hole 153 formed in the head cover 44 of the lock cylinder 117 communicates with the fluid introduction hole 52 of the lock cylinder 17 via the fluid communication path 363, and supplies compressed air from the lock pressure chamber 47 of the lock cylinder 117. I am receiving it. Therefore, the lock fluid is supplied to the pressure chamber 47 of the lock cylinder 17 next to the pressure chamber 47 of the lock cylinder 117.

[0082] The release supply / discharge port 364 is connected to the forward fluid path 367 by the release fluid path 370. The release supply / discharge port 364 communicates with the forward pressure chamber 34. By switching the two switching positions, the flow path switching valve 366 connects one of the forward fluid flow path 367 and the reverse fluid flow path 368 to the compressed air source 365 to supply compressed air, and the other to the outside. The compressed air is released to the atmosphere.

Next, the operation of the present embodiment will be described. When the compressed air source 365 is connected to the forward fluid passage 367 by switching the passage switching valve 366 to open the retreat fluid passage 368 to the atmosphere, compressed air is supplied to the forward pressure chamber 34. As a result, the main piston 23 is pressed forward by the pressing force, and the piston rod 14 moves forward. Here, when the two port units 29 and 129 are in a fastening state, the compressed air to be supplied is supplied because the main piston 23 does not move and the volume of the forward pressure chamber 34 is fixed. Is introduced as unlocking fluid into the unlocking pressure chambers 48 via the unlocking fluid flow path 370 and the unlocking fluid supply path, and the fastening of the lock units 29 and 129 is forcibly released. After the release of the fastening, the reciprocally movable main piston 23 is pushed by the compressed air and moves forward.

[0084] During the forward movement, the compressed air pushed out of the retreat pressure chamber 35 passes through the restrictor 368b and is released to the atmosphere. At this point, the locking fluid passage 369 is displaced from the retreat fluid passage 368. The connection is made at a position downstream of the throttle 368b, so no back pressure is introduced. Even if the forward movement is restricted due to the connection plate 16 contacting the external member or reaching the forward limit position, as long as the compressed air is supplied to the forward fluid passage 367, each lock unit 29, The release state of 129 is maintained.

Next, when the compressed air source 365 is connected to the retreating fluid passage 368 by switching the passage switching valve 366 and the forward fluid passage 367 is opened to the atmosphere, the compressed air is supplied to the retreating pressure chamber 35. By being supplied, the main piston 23 is pressed backward by the pressing force, and the piston rod 14 moves backward. During the backward movement, the compressed air pushed out of the forward pressure chamber 34 passes through the throttle 367b and is released to the atmosphere.At this point, the release fluid flow path 370 is moved from the throttle 367b to the forward fluid flow path 367. Since the connection is made at the upstream position, back pressure is introduced into each unlocking pressure chamber 48 via the unlocking fluid flow path 370 and the unlocking fluid supply path, and each lock unit 29, 129 Maintain the state where the fastening is released. [0086] As shown in Fig. 9, when the cylinder rod 307 contacts the stage stopper 308 located on the retreat side of the cylinder stopper 307 or the like, the retraction movement of the piston rod 14 is restricted. The back pressure in 48 is discharged from the throttle 367b through the release fluid flow path 370, and the pressure drops. Further, since the volume of the retraction pressure chamber 35 is fixed without moving the main piston 23, the supplied compressed air is supplied as lock fluid through the lock fluid flow path 369 and the lock fluid supply path. The lock units are introduced into the lock pressure chamber 47, and the lock units 29 and 129 are forcibly fastened.

At this time, compressed air is first introduced into the lock pressure chamber 47 in the lock cylinder 117, and then compressed air is introduced into the lock pressure chamber 47 in the lock cylinder 17. Therefore, there is a time difference between the operation of the two fastening rods 45 and 145, and the play can be sequentially removed from the two lock units 29 and 129, so that the moving position of the piston rod 14 can be fixed well. Become.

[0088] In particular, in the present embodiment, since lock unit 129 is operated first and lock unit 29 is subsequently operated, retreat movement of piston rod 14 and connecting plate 16 is performed as shown in FIG. The play in each of the lock units 29 and 129 can be best removed in a restricted use type in which the lock unit 29 is fixed in a limited state, and secure fixing is possible. By changing the length of the fluid communication path 363 between the lock pressure chambers 47, the operation time difference can be reduced.

The supply of compressed air to both the forward fluid passage 367 and the backward fluid passage 368 is stopped, and either the unlocking fluid or the back pressure is supplied to each unlocking pressure chamber 48. In the case where the piston rod 14 has been removed, the fastening rods 45 and 145 are pushed down to the operating position by the thrust of the locking spring member 46 as in the above embodiment, and the lock units 29 and 129 are engaged and the piston rod 14 is stopped. The axial position will be fixed.

As described above, the fluid pressure cylinder 311 of the present embodiment operates when the backward movement of the piston rod 14 is restricted due to the contact of the cylinder stopper 307 or the like, or when the supply of the compressed air is completely stopped. Thus, the axial position of the piston rod 14 can be reliably fixed in both the forward and backward directions.

[0091] Fig. 10 shows the fluid pressure for supplying compressed air to the drive cylinder and the two lock cylinders. It is a circuit diagram which shows the modification of a circuit. This fluid pressure circuit is applied to a fluid pressure cylinder 311 in which a retraction supply / discharge port 321 communicates only with the retraction pressure chamber 35 as shown in FIG. 8, and is shown in FIGS. 8 and 9 in FIG. The same reference numerals are given to members common to the above members.

[0092] The forward supply / discharge port 20 is connected to a forward fluid passage 367, and the backward supply / discharge port 321 is connected to a backward fluid passage 368. The forward pressure chamber 34 and the backward pressure are connected to each other. Compressed air is selectively supplied to the chamber 35 by the flow path switching valve 366. As shown in FIG. 10, the flow path switching valve 366 has a position for discharging the compressed air in the pressure chambers 34 and 35, a position for supplying the compressed air to the forward pressure chamber 34, and a position in the retreat pressure chamber 35. The position can be switched to the position where compressed air is supplied.

The supply / discharge port 364 communicating with the lock release pressure chamber 48 of each of the lock cylinders 17 and 117 via the unit storage chamber 33 is connected to a lock release fluid flow path 371. The lock fluid passage 372 is connected to the fluid introduction holes 52 and 152 communicating with the fluid. A switching valve 373 provided between each of the fluid flow paths 371 and 372 and the compressed air pressure source 365 communicates a position that connects the input port 373a and the output port 373b with the input port 373a and the output port 373c. Is switched to Therefore, when the piston rod 14 is moved forward, the compressed air is supplied from the forward supply / discharge port 20 while the compressed air is supplied into the unit storage chamber 33 via the supply / discharge port 364, and the piston port is closed. When the crew 14 is moved backward, compressed air is supplied from the retreating supply / discharge port 321 in a state where compressed air is supplied into the unit storage chamber 33 via the supply / discharge port 364.

When the piston rod 14 reaches the forward limit position or the backward limit position, the switching valve 366 discharges the compressed air in the forward pressure chamber 34 and the reverse pressure chamber 35, and the fluid inlet holes 52, 152. To supply compressed air into the respective lock pressure chambers 47. The fluid pressure circuit shown in FIG. 10 can be applied to the case where the plunger 50 is incorporated in one of the two lock cylinders 17 and 117 as shown in FIG. , 117, the plunger 50 is not used.

[0095] The present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist thereof. For example, this hydraulic cylinder 11, 211, 311 Although it is used for fixing the panel material W constituting the above to the handling device 4, it can be used for fixing other than the panel material, and can be used for purposes other than fixing in the handling device 4.

[0096] Further, when operating the lock units 29 and 129, the steel ball 36 is pressed against the piston rod 14, but instead of the ball, for example, a slit is formed in an annular member, and the slit is formed by elastic deformation. Alternatively, a member whose inner diameter is reduced by using a member may be used. It is needless to say that a force other than air may be used as the fluid for operating the fluid pressure cylinders 11, 2 11, 311.

Industrial applicability

[0097] This fluid pressure cylinder is applied when a work holder for holding a work is attached to a moving member such as a robot arm to carry the work.

Claims

The scope of the claims

[1] A drive cylinder in which a piston rod having a main piston is accommodated so as to be reciprocally movable in an axial direction and a forward pressure chamber and a backward pressure chamber defined by the main piston are provided, and the drive cylinder is attached to the drive cylinder. A first mouthpiece having a first lock sleeve which is incorporated in a unit housing chamber of a lock unit and a housing and fastens the piston rod.

-

A second lock unit that is incorporated in the unit storage chamber and has a second lock sleeve for fastening the piston rod;

A fastening position attached to the lock unit housing and having a first pressing surface that contacts a first inclined surface formed on the first lock sleeve, and a fastening position approaching the piston rod and a fastening release separating from the piston rod. A first lock cylinder accommodating a first fastening port reciprocally movable to and from a position;

A fastening position attached to the lock unit housing and having a second pressing surface that contacts a second inclined surface formed on the second lock sleeve, and a fastening position approaching the piston rod and a fastening release separating from the piston rod. A second lock cylinder accommodating a second fastening port that is reciprocally movable to and from a position.

[2] The hydraulic cylinder according to claim 1, wherein the first and second lock sleeves are installed so that first and second inclined surfaces face each other.

3. The fluid pressure cylinder according to claim 1, wherein the first lock sleeve has a first inner peripheral surface having a tapered shape, and the first lock unit contacts the first inner peripheral surface. A first retainer that holds a plurality of steel balls and is movably fitted to the piston rod in the axial direction, and the steel balls are attached to the first inner peripheral surface via the first retainers. A first spring member for adjusting the spring force in the pressing direction,

The second lock sleeve has a second inner peripheral surface having a tapered shape opposite to the first inner peripheral surface, and the second lock unit is provided on the second inner peripheral surface. A second retainer that holds the plurality of contacting steel balls and is movably fitted in the piston rod in the axial direction, and the second inner periphery of the steel balls via the second retainer; Press against surface A second spring member for applying a spring force in a direction.

4. The fluid pressure cylinder according to claim 1, wherein the first and second lock cylinders reduce a spring force of the fastening rod in a direction toward the piston rod. A fluid pressure cylinder comprising:

[5] The fluid pressure cylinder according to claim 1, wherein a restrictor for communicating the unit housing chamber and the retreat pressure chamber is provided on a partition wall separating the unit housing chamber and the retreat pressure chamber, A supply / discharge port to which a source is connected via a retreat channel is connected to the unit housing chamber, and fluid supply and discharge are performed to the retreat pressure chamber via the unit housing chamber. Fluid pressure cylinder.

6. The fluid pressure cylinder according to claim 5, wherein a check valve that allows the flow of the fluid toward the unit housing chamber and prevents the flow of the fluid in the opposite direction is provided on the partition wall. A hydraulic cylinder characterized by the following.

7. The fluid pressure cylinder according to claim 1, wherein the first fastening rod is a lock pressure chamber that reduces a thrust force in a direction toward the piston rod with respect to the first fastening rod; A lock release pressure chamber for applying a thrust in a direction away from the ston rod, and a first lock piston for partitioning the inside of the first lock cylinder, wherein the second fastening rod is arranged in A second lock that partitions the inside of the second lock cylinder into a lock pressure chamber that applies thrust in a direction away from the piston rod and a lock pressure chamber that applies thrust in a direction away from the piston rod. A fluid pressure cylinder having a piston.

[8] The fluid pressure cylinder according to claim 7, wherein a fluid pressure source is connected to a supply / discharge port communicating with the first lock pressure chamber via a fluid introduction path, and the first lock pressure chamber and the second lock pressure chamber are connected to each other. A fluid pressure cylinder connected to the lock pressure chamber in series by a fluid communication passage, and supplying a fluid of the fluid pressure source to the second lock pressure chamber via the first lock pressure chamber. .

9. The fluid pressure cylinder according to claim 8, wherein a through hole communicating with the supply / discharge port is formed, and the cylinder is movably fitted in an axial direction into a receiving hole formed in the first fastening rod. A plunger having a piston portion that is to be assembled is incorporated into the first fastening rod, and the fluid is moved when the first fastening rod moves a predetermined stroke toward the piston rod. A fluid pressure cylinder that communicates an introduction path with the first lock pressure chamber. 10. The hydraulic cylinder according to claim 9, wherein the first fastening rod applies a pressing force to the first lock sleeve toward a distal end of the piston rod.