WO2003102429A1

WO2003102429A1 - Fluid pressure cylinder and clamping device

Info

Publication number: WO2003102429A1
Application number: PCT/JP2003/006662
Authority: WO
Inventors: Akio Nakata; Masakazu Tetsuka
Original assignee: Koganei Corporation
Priority date: 2002-06-04
Filing date: 2003-05-28
Publication date: 2003-12-11
Also published as: TWI229027B; JP2004011685A; JP3904979B2; TW200307591A

Abstract

A piston rod (18) is secured to a piston (26) built in the cylinder body (23). A brake unit (40) is disposed in a cylindrical body (24) for brake and movement of the piston rod (18), at a specified stroke position, is regulated in the retreating direction by means of the brake unit (40). The brake unit (40) is applied with a load in the advancing direction by a taper rod (63) urged toward the brake unit (40) by a spring member (65). Consequently, a load is applied in the advancing direction to the piston rod (18) by the taper rod (63) through the brake unit (40) even if fluid in a fluid chamber (27a) for advancing is discharged.

Description

Specification

Fluid pressure cylinder and clamp device

The present invention relates to a hydraulic cylinder which reciprocates a piston rod in the axial direction by the pressure of a fluid such as compressed air, and more particularly to a technique which is useful when applied to a clamp device for positioning and fixing a panel material. Background art

For example, an automobile body is formed by assembling a plurality of panel members constituting the body by joining means such as spot welding. In order to assemble an automobile body, for example, as shown in Japanese Patent Application Laid-Open No. 4-283034, a body having work stages arranged at predetermined intervals with a panel material fastened to a carrier by a clamp member. While moving the carrier to the assembly line, predetermined work such as spot welding is performed at each work stage. If the final stage and the first stage of the body assembly line are connected by a return line, the transport trolley can be recycled.

It is necessary to provide a clamp member on the transport trolley to fix the panel material with the panel material positioned. When this clamp member is driven by a pneumatic cylinder, the pipe that supplies air pressure to the pneumatic cylinder for operating the clamp member must be removed from the transport cart while the transport cart is moving. No. Therefore, in the first stage and the last stage, compressed air is supplied to the pneumatic cylinder for operating the clamp member provided on the transport trolley to open and close the clamp member. When the transport cart moves, it is necessary to remove the pipe from the transport cart and hold the panel material at the clamp position.

For this reason, a pneumatic cylinder having a brake may be used to brake the piston gate in a state where the supply of air pressure to the pneumatic cylinder for operating the clamp member is stopped. However, a pneumatic cylinder with a brake is designed to prevent the biston opening connected to the clamp member from being loosened, so that the clamping force cannot be continuously applied to the clamp member. Therefore, if an impact force acts on the clamp member during the transport process and the clamp member is loosened, the panel member may not be able to apply the clamping force, that is, the fastening force, and the panel material may be loosened.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fluid in which a piston port can be fixed at a predetermined position and an axial load can be applied to the piston port at the fixed position. It is to provide a pressure cylinder.

Another object of the present invention is to clamp a panel material using a cylinder having a piston rod driven by fluid pressure, and to add a clamping force to the panel material even when the supply of fluid pressure to the cylinder is stopped. An object of the present invention is to provide a clamping device that can perform the above-described operations. Disclosure of the invention

The fluid pressure cylinder according to the present invention includes a cylinder body having a cylinder tube having an end cover attached to one end and a mouth cover attached to the other end; and a reciprocating axially mounted inside the cylinder tube, A piston for partitioning the fluid chamber for use and the fluid chamber for retreat, a piston rod mounted on the cylinder body so as to reciprocate in the axial direction, fixed to the biston and protruding outside from the rod cover. Locking means operably provided in a coupled state and a released state with respect to the piston port, and for restricting a return movement of the screw rod when the piston port moves to a predetermined position; A plunger member provided to be movable back and forth toward the locking means, and a spring member for urging the plunger member to apply a spring force in an advance direction. And a load applying means for applying a load in a forward direction or a backward direction to the hook means, and when the lock means is in a coupled state, the load is maintained even if the fluid in the fluid chamber is discharged. It is characterized in that a load is applied to the piston port through the port means by the applying means.

In the clamp device of the present invention, an end force par is attached to one end and a rod is attached to the other end. A cylinder body having a cylinder tube to which a force par is attached; a piston mounted in the cylinder tube so as to be reciprocally movable in the axial direction to partition a forward fluid chamber and a backward fluid chamber; A biston rod which is mounted to be reciprocally movable in the axial direction and is fixed to the biston and protrudes outside from the rod cover; and A clamp arm that is operably provided in a coupled state and a released state with respect to the piston port, and regulates a return movement of the piston port when the piston rod moves to a predetermined position. Locking means, a plunger member provided to be movable forward and backward toward the locking means, and the plunger. A spring member for urging the jaw member with a spring force in an advance direction; and a load applying unit for applying a load in a forward direction or a backward direction to the hook unit, and the locking unit is in a connected state. In this case, even if the fluid in the fluid chamber is discharged, a load is applied to the clamp arm by the load applying means via the hook means and the piston rod.

The fluid pressure cylinder and the clamp device according to the present invention are characterized in that the plunger member is provided so as to be movable forward and backward toward an inclined surface formed in the lock means.

The fluid pressure cylinder and the clamp device according to the present invention are characterized in that the locking means is brought into a connected state by a hook plate having a hook hole through which the biston rod passes is inclined with respect to the biston rod. And BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a plan view showing a part of an assembly line of an automobile body in which panel materials constituting an automobile body are transported by a transport trolley.

FIG. 2 is an enlarged front view showing the clamp device shown in FIG.

FIG. 3 is an enlarged sectional view showing the fluid pressure cylinder shown in FIG.

FIG. 4A is a half sectional view showing the rod force par shown in FIG. 3, and FIG.

) Is a side view as viewed from the direction of the arrow B—B in FIG. Is a cross-sectional view taken along the line CC in FIG. (A), and FIG. 4 (D) is a cross-sectional view taken along the line DD in FIG.

FIGS. 5 (A) to 5 (C) are schematic diagrams showing the outline of the operation of the brake unit and the taper lock cylinder.

FIG. 6 is an enlarged front view showing another type of clamping device. BEST MODE FOR CARRYING OUT THE INVENTION

As shown in FIG. 1, the transport vehicle 10 has a plurality of wheels 11 and travels from the first stage S1 to the final stage Sn. In the first stage S1, the panel material constituting the vehicle body is carried into the transport trolley 10 as the work W, and in the final stage S n, the work W after the predetermined assembling work is removed from the transport trolley 10 . Each carrier 10 is provided with a clamp device 12 for clamping or fastening the work W. In FIG. 1, each of the transport vehicles 10 is provided with two clamp devices 12, but an arbitrary number of clamp devices 12 are provided on the transport vehicle 10 according to the size of the work W and the like. FIG. 2 is an enlarged front view showing the clamp device 12 shown in FIG. 1, and the carrier 10 is provided with a work support 13 for supporting the work W. Has a clamp arm 14 for clamping the work W with the support 13 so as to be swingable about the pin 15a. A hydraulic cylinder 16 is fixed to the support base 13 by a pin 15b at the clevis 17 fixed to the hydraulic cylinder 16 so that it can swing freely.The piston rod 18 of the hydraulic cylinder 16 is clamped. It is connected to the arm 14 by a pin 15c. When the piston arm 18 moves forward, that is, moves in a direction that protrudes from the inside of the fluid pressure cylinder 16, the clamp arm 14 clamps the work W when it moves to a predetermined stroke position. FIG. 3 is an enlarged cross-sectional view of the hydraulic cylinder 16 shown in FIG. 2. The hydraulic cylinder 16 has a cylinder tube 20 and an end cover 21 attached to one end thereof. And a rod body 22 attached to the other end. Mouth cover 2 2 and brake cylinder 2 4 It is attached to the other end of the cylinder tube 20 via the plastic stopper 25, and the cylinder 24 and the plastic stopper 25 constitute a cylinder body 23.

A piston 26 is mounted in the cylinder tube 20 so that it can reciprocate in the axial direction. The piston 26 allows the cylinder tube 20 to have a forward fluid chamber 27a and a retreat fluid chamber 27b. It is divided into and. When the compressed air is supplied to the forward fluid chamber 27 a, the piston 26 moves forward toward the rod cover 22, and when the compressed air is supplied to the backward fluid chamber 27 b, the piston 26 retracts toward the end cover 21. You will move. The piston 26 has a first disk 28 provided with a sealing material 28 a and a second disk 29 having a cylindrical portion 29 a, and the cylindrical portion 29 of the second disk 29. A female screw is formed on the inner peripheral surface of a. Further, the piston 26 is provided with a ring-shaped magnet 30 sandwiched between the first disk 28 and the second disk 29, and a sensor (not shown) by this magnet 30 Is detected. 29 b is a wear ring.

On the other hand, Biston Rod 18 has a mouth cover 22 and a brake unit

It is mounted on the cylinder body 23 so that it can reciprocate in the axial direction, supported by

As shown in FIG. 2, the clamp arm projects outward from the rod cover 22.

It is pin connected to 14. In addition, the button 18 is fixed to the piston 26 by connecting a male screw formed at the end thereof to a female screw of the cylindrical portion 29a, and is axially integrated with the piston 26. To move to.

FIG. 4A is a half sectional view showing the rod force par 22 shown in FIG.

(B) is a side view as viewed from the direction of arrow B—B in FIG.

(C) is a cross-sectional view along the line CC in FIG. (A), and FIG. 4 (D) is a cross-sectional view along line DD in FIG. As shown in Fig. 4 (C), three supply / discharge ports 31 are formed in the rod cover 22, and supply / discharge hoses and pipes are connected to either one of the supply / discharge ports depending on the usage condition. Can be connected. The unused supply / discharge port 31 is closed by the plug 31a, and the used supply / discharge port is connected to the air pressure source, exhaust port, and hose or piping via a flow path switching valve. The supply / discharge port 31 is switched to and connected to an air pressure source and an exhaust port by a flow path switching valve.

As shown in FIG. 4 (C), a guide cylinder 32 is incorporated inside the mouth cover 22, and the outer peripheral surface of the guide cylinder 32 is connected to three supply / discharge ports 31. A through-groove 33 is formed, and a throttle 35 is provided in a communication hole 34 for communicating the groove 33 with the inside of the guide cylinder 32. An air supply passage 24 a is formed in the brake cylinder 24, a communication passage 25 a is formed in the brake unit stop 25, and an air supply passage is formed inside the guide cylinder 32. It communicates with the retreating fluid chamber 27b via the communication passage 24a and the communication passage 25a. Therefore, each supply / discharge port 31 communicates with the retraction fluid chamber 27 b via the throttle 35. On the other hand, as shown in FIG. 4 (D), a throttle 37 is also provided in a communication flow path 36 for communicating the inner end face of the rod cover 22 with the inside of the guide cylinder 32.

As shown in FIG. 3, similarly, three supply / discharge ports 38 are respectively formed in the end force par 21 so as to communicate with the forward fluid chamber 27a, so that the end force par 21 does not correspond to the use state. A supply / discharge hose or pipe can be connected to one of the supply / discharge ports. The unused supply / discharge port 38 is closed by a plug 38a, the used supply / discharge port is connected to the air pressure source and exhaust port via a flow path switching valve and a hose or piping, and the supply / discharge port 38 is The passage switching valve switches between the air pressure source and the exhaust port and connects them. Restrictions similar to those described above are incorporated between the respective supply / discharge ports 38 and the forward fluid chamber 27a.

Inside the brake cylinder 24, a brake cut 40 is provided between the plastic cut stopper 25 and the mouth cap 22 to serve as a hook means. 40 is operable in the coupled state and the released state with respect to the biston opening 18 by switching the opening plate 42 incorporated in the casing 41 between the upright state and the inclined state. . The casing 4 1 is composed of a main case 4 3 formed in a cylindrical shape with a bottom, and a cap 4 4 fixed to an open end of the main case 4 3. 3a and cap 4 4 have through holes 4 5 through which the piston rod 18 passes, respectively.

4 6 are formed. Inside the casing 41 is the inner peripheral surface of the main case 43. A force par plate 47 formed in a disc shape is fitted adjacent to the inner surface of the cap 44 and is engaged with the support groove 43 b formed on the cap 44. A through hole 47 a through which the biston rod 18 penetrates is formed, and both end faces are formed perpendicular to the axis.

The lock plate 42 is formed in a disk shape that is in sliding contact with the inner peripheral surface of the casing 41, and is disposed adjacent to the force-par plate 47. A lock hole 42 a formed with an inner diameter slightly larger than the outer diameter of the piston rod 18 is provided in the axis of the lock plate 42, and the piston rod 18 is provided with the lock hole 42 a. Penetrating. On the outer peripheral surface of the lock plate 42, a flange portion 42b is formed in a predetermined range on the lower side in the drawing, that is, one side in the radial direction, and the flange portion 42b is engaged with the support groove 43b. Have been combined. Accordingly, the lock plate 42 has one end face in contact with the end face of the force-par plate 47 and the upright state in which the axial direction of the lock hole 42 a and the axial direction of the biston rod 18 are aligned. With the engaging portion between 2b and the support groove 4 3b as a fulcrum, the lock plate 4 2a is tilted counterclockwise in the figure with respect to the force par plate 47, that is, inclined to the bottom wall 43a side. Is movable between an inclined state in which the piston is inclined with respect to the axial direction of the piston rod 18. The concave groove 4 3c formed on the outer peripheral surface of the main case 4 3 communicates between the force plate 4 7 and the lock plate 4 2 through the vent hole 4 3 d. Is formed with a supply / exhaust hole 24b for communicating the concave groove 43c with the outside. Therefore, the space between the force plate 47 and the lock plate 42 communicates with the outside, so that when the lock plate 42 moves with respect to the cover plate 47, the force can be released. A compression coil spring 48 is provided between the par plate 47 and the lock plate 42 on the upper side in the drawing, that is, on the other side in the radial direction of the lock plate 42. As a result, a spring force directed toward the bottom wall portion 43a is applied to the lock plate 42. Therefore, the lock plate 42 is tilted counterclockwise in the drawing, that is, toward the bottom wall 43 a with the engagement between the flange 42 b and the support groove 43 b as a fulcrum due to the spring force of the compression coil spring 48. Rotation force is applied in the direction of A brake release pressure chamber 49 is provided between the hook plate 42 and the bottom wall 43a, and the pressure chamber 49 is formed through a through hole 45 formed in the bottom wall 43a. To the retraction fluid chamber 27b. I mean The pressure chamber 49 communicates with the supply / discharge port 31 via the retraction fluid chamber 27 b. Therefore, when compressed air is supplied from the supply / discharge port 31, compressed air is supplied into the pressure chamber 49, and when compressed air is discharged from the supply / discharge port 31, the compressed air in the pressure chamber 49 is discharged. become.

The brake unit 40 is connected by discharging the compressed air in the pressure chamber 49. In other words, when the compressed air in the pressure chamber 49 is discharged, the lock plate 42 is moved by the spring force of the compression coil spring 48 so that the engagement between the flange 42 b and the support groove 43 b serves as a fulcrum. As a result, the opening end of the lock hole 42 a comes into strong contact with the outer peripheral surface of the piston rod 18. In this state, if the piston rod 18 attempts to move in the return direction, that is, the retreating direction, the lock plate 42 is more strongly attached to the bottom wall by the frictional force between the lock plate 42 and the piston rod 18. 4 3 Rotational force toward the a side is applied, the frictional force between the lip plate 42 and the piston rod 18 increases, and the backward movement of the piston rod 18 is restricted. Become. On the other hand, when the piston rod 18 moves forward with the lock plate 42 inclined, the friction between the lock hole 42 a and the piston rod 18 causes the lock plate 42 to move forward. Of the compression coil spring 48, the frictional force between the lock plate 42 and the piston hole 18 decreases, and the piston rod 18 moves forward freely. can do. Thus, in the brake unit 40, the piston unit 18 is connected to the piston rod 18 only when the piston rod 18 moves in the backward direction.

On the other hand, when compressed air is supplied to the pressure chamber 49, the brake unit 40 is released. In other words, when compressed air is supplied to the pressure chamber 49, the pressure in the pressure chamber 49 increases, and the pressure plate 42 is pressed against the cover plate 47 against the compression coil spring 48 by this pressure. It will be upright. Therefore, a gap is formed between the piston rod 18 and the lock hole 42a, and the piston rod 18 can freely move with respect to the lock plate 42, that is, the brake unit 4◦.

A tapered surface 51 as an inclined surface is formed on the bottom wall portion 4 3 a of the main case 43, and the tapered surface 51 contacts the brake unit stopper 25 to form the brake unit 40. Brake unit stopper 2 Movement in 5 directions is restricted. Is controlled. A spring member 52 is mounted between the cap 44 and the rod cover 22. A compression coil spring is used as the spring member 52, and the brake unit 40 is formed by the spring member 52. It is pressed against the brake unit stopper 25.

A taper lock cylinder 60 as a load applying means is attached to the brake cylinder 24.The taper lock cylinder 60 has a cylinder body 61 in which a rod cover and a cylinder tube are integrally formed. Biston 62 is incorporated in the cylinder tube so that it can reciprocate in the axial direction. A taper rod 63 as a plunger member is formed in the piston 62 in a body, and a tapered surface 63 a that is in contact with the tapered surface 51 is formed at the tip of the taper rod 63. A spring member 65 is incorporated between the force par 64 fixed to the cylinder body 61 and the piston 62. As the spring member 65, a compression coil spring is used, and the spring member 65 applies a spring force in the advance direction to the piston 62. Therefore, the tapered rod 63 is urged by the spring member 65 to advance toward the tapered surface 51 formed on the rear end surface of the brake unit 40. When the tapered rod 63 advances, the tapered surface 63 a of the tapered rod 63 comes into sliding contact with the tapered surface 51 of the brake unit 40, and a load is applied to the brake unit 40 in the forward direction, that is, in the rod cover 22 direction. Will be done. With this load, the brake unit 40 moves to the side of the force member 22 against the spring force of the spring member 52 within the range of the stroke Sa between the cap 44 and the rod cover 22. The stop position is determined according to the reaction force from the work W applied to the brake unit 40 via the piston rod 18. The tapered surface 63a is formed at an acute angle with respect to the axis of the tapered rod 63, and the tapered surface 51 is formed at an obtuse angle with respect to the axis of the brake unit 40. The spring force applied to 63 is boosted and transmitted as a load to brake unit 40, and the load from brake unit 40 prevents taper rod 63 from retreating. .

To move the tapered rod 6 3 backward against the spring force, A communication passage 66 branched from the air supply passage 24 a is formed in 1, and the communication passage 66 communicates with a fluid chamber 67 in a tape lock cylinder 60. Therefore, when compressed air is supplied from the supply / discharge port 31, the compressed air flows into the fluid chamber 67 through the communication passage 66, and the tapered rod 63 moves backward together with the piston 62. The pressure in the fluid chamber 67 necessary to move the taper rod 63 backward is set to be smaller than the pressure in the pressure chamber 49 required to bring the lock plate 42 upright in the brake unit 40. I have. Therefore, when the compressed air is supplied from the supply / discharge port 31, the tapered rod 63 is retracted before the hook plate 42 becomes the upright state, and the compressed air is supplied from the supply / discharge port 31. Is discharged, the lock plate 42 is inclined before the tapered rod 63 advances toward the brake unit 40.

FIGS. 5A to 5C are explanatory diagrams schematically showing the operation of the brake unit 40 and the taper lock cylinder 60. FIG. First, when compressed air is supplied from the supply / discharge port 38 to the forward fluid chamber 27a while the piston 26 is at the retreat limit position, the piston 26 and the piston rod 18 are shown in FIG. 5A, the clamp arm 14 moves forward toward the predetermined stroke position, that is, the position where the workpiece W is clamped. This stroke position is a position that is retracted by a predetermined stroke with respect to the forward limit position of the piston 26, in this case, by the stroke Sa of the brake unit 40. When the piston 26 moves forward, back pressure is generated in the retreating fluid chamber 27 b, the pressure chamber 49 and the fluid chamber 67, and the back pressure causes the lock plate 42 to stand upright, that is, the brake unit. 40 is in the released state, and the tapered rod 63 is in the retracted position. When the piston 26 reaches the predetermined stroke position, the back pressure in the pressure chamber 49 and the fluid chamber 67 gradually decreases, and as shown in FIG. As a result, the brake unit 40 is tilted to be in the coupled state, and the movement of the piston rod 18 in the retreating direction with respect to the brake unit 40 is restricted. In this case, the piston rod 18 switches the brake unit 40 to the coupled state when the clamp arm 14 reaches the stroke position for clamping the workpiece W. The force of the brake unit 40 is the piston rod 1 8 stroke position Instead, it can be connected to the biston opening 18. Therefore, even if the stroke position of the piston 18 is changed at the time of clamping due to deformation of the work W, the brake unit 40 can be surely connected to the piston rod 18. it can.

When the back pressure in the fluid chamber 67 further decreases from this state, the taper rod 63 moves forward toward the taper surface 51 of the brake unit 40 as shown in FIG. Then, the advancing movement of the tapered rod 63, that is, the spring force applied to the tapered rod 63, is converted into a forward load on the break unit 40 via the tapered surface 63a and the tapered surface 51. If the compressed air in the forward fluid chamber 27a is discharged to the outside in this state, no load is applied to the piston rod 18 due to the pressure in the forward fluid chamber 27a, but the tape rod 6 Since the spring force of the spring member 65 is applied to 3, it advances toward the brake unit 40 regardless of the stop of the supply of the compressed air. Therefore, the piston rod 18 is restricted from being connected to the brake unit 40, that is, the backward movement with respect to the brake unit 40, and the brake unit 40 is subjected to a forward load by the taper rod 63. Therefore, even if the compressed air in the forward fluid chamber 27 a is discharged to the outside, the forward load is applied to the piston 18 by the tapered rod 63 via the brake unit 40. become. In other words, even if the supply of compressed air to the forward fluid chamber 27a is stopped and the internal air is exhausted to the outside, the fluid pressure cylinder 16 can be connected to the piston rod 18 via the tapered rod 40 via the break unit 40. 6 A load from 3 can be applied.

In order to supply compressed air to the fluid pressure cylinder 16, as shown in FIG. 2, a supply / discharge hose 70 connected to a supply / discharge port 31 is provided on a supply / discharge joint 70 provided on the carrier 10. And a supply / discharge hose 71b connected to the supply / discharge port 38, and supply compressed air to the forward fluid chamber 27a and the reverse fluid chamber 27b.

The discharge of the compressed air from the inside is performed via a supply / discharge joint 70.

On the other hand, the first stage S 1 shown in FIG. 1 is provided with a supply / discharge joint 72 adjacent to the carrier 10, and the supply / discharge hood connected to the supply / discharge joint 72 is provided. The source is connected to an air pressure source (not shown) via a flow path switching valve. These supply / discharge joints 70 and 72 are connected to each other when the carrier 10 is at the position of the first stage S 1, and are separated from an air pressure source provided outside the carrier 10. The compressed air can be supplied to each of the fluid chambers 27a and 27b, and the air in the fluid chambers 27a and 27b can be discharged to the outside. As a result, after the work W is loaded onto the work support 13 with the clamp arm 14 opened, the work W is fastened by closing the clamp arm 14 with the fluid pressure cylinder 16. can do.

By moving the transport vehicle 10 in the state where the work W is fastened in this manner, the transport vehicle 10 can perform a predetermined assembling operation at each stage constituting the vehicle body assembly line. The final stage S n shown in FIG. 1 is provided with a supply / discharge joint 72 a connected to the supply / discharge joint 70 on the bogie side to supply compressed air to the retraction fluid chamber 27 b. By opening the clamp arm 14 at this stage Sn, the work W after the completion of the predetermined assembly can be carried out of the line.

Next, the procedure for clamping the workpiece W by the clamping device 12 using the above-described fluid pressure cylinder 16 will be described. To move the piston rod 18 backward and open the clamp arm 14, the supply / discharge joint 70 , 72 to supply compressed air to the retreating fluid chamber 27b. In this state, the piston 26 is at the retreat limit position, the piston rod 18 is also at the retreat limit position, the clamp arm 14 is opened, and the work W can be carried in. In addition, the brake unit 40 is in the angular release state, the biston opening 18 is movable in the axial direction, the taper rod 63 is retracted, and the brake unit 40 is in the spring state. The member 52 is pressed against the break unit stopper 25. To close the clamp arm 14, compressed air is supplied to the forward fluid chamber 27 a via the supply / discharge port 38. As a result, the piston 26 and the piston rod 18 move forward, and when the piston 26 and the piston rod 18 move to a predetermined stroke position, the clamp arm 14 is closed. When the clamp arm is closed, the lock plate 42 tilts as shown in FIG. When the retracting movement of the piston rod 18 is regulated by the brake unit 40, the tapered rod 6 is restricted as shown in FIG. 5 (C). 3 moves forward toward the tapered surface 51 of the brake unit 40. Then, the taper surface 63 a of the taper rod 63 comes into contact with the taper surface 51 of the brake unit 4◦, and a forward load is applied to the brake unit 40. Since the backward movement of the biston opening 18 with respect to the brake unit 40 is regulated, when a forward load is applied to the brake unit 40, the load is also transferred to the biston rod 18. If there is a gap between the clamp arm 14 and the workpiece W due to vibration or the like, the load applied by the tapered rod 63 causes the piston rod 18 to become integral with the brake unit 40 and the rod cover 22 side. Will be moved to If the compressed air in the forward fluid chamber 27 a is discharged to the outside in this state, no load is applied to the piston rod 18 depending on the pressure in the forward fluid chamber 27 a, but the taper rod 6 3 Since the spring force of the spring member 65 is urged in, the load on the brake unit 4 is maintained, and the forward load is applied to the piston rod 18 via the brake unit 40. If looseness occurs between the clamp arm 14 and the workpiece W due to vibrations caused by the movement of the bogie, etc., the piston opening 18 moves forward with the brake unit 40 to absorb the looseness. Will be done. Therefore, when clamping the work W as shown in FIG. 2 by the clamp arm 14 connected to the fluid pressure cylinder 16, the supply of the compressed air to the forward fluid chamber 27 a is stopped and the internal Even if the air is discharged to the outside, the load, that is, the clamping force against the workpiece W is applied to the clamp arm 14.

The workpiece W thus clamped by the clamp arm 14 is transported by the transport cart.

10 When transporting by 0, supply / discharge joint 7 2

It will be removed from 0. When removed, the fluid chambers 27a and 27b are open to the air, so that the air supplied to the forward fluid chamber 27a is discharged to the outside. As a result, it is added to the piston rod 18 through the piston 26. Although the clamping force is lost, a load is applied to the piston opening 18 from the tapered rod 63 via the brake unit 40. Therefore, even if vibration or impact is applied to the transport vehicle 10 in the process of transporting the transport vehicle 10, the work W can be reliably held without loosening the fastening force of the clamp arm 14 to the workpiece "W.

To remove the workpiece W at the final stage S n, supply compressed air to the retraction fluid chamber 27 b.First, the taper rod 63 moves backward together with the piston 62 due to the pressure increase in the fluid chamber 67, 6 3 Taper surface 6 3 a Force S Brake unit 40 Detaches from taper surface 51 of 40. Then, the brake unit 40 is moved toward the brake unit stopper 25 by the spring member 52. Subsequently, the pressure in the pressure chamber 49 rises due to the supply of compressed air into the retreating fluid chamber 27 b, and the lock plate 42 becomes upright, that is, the brake unit 40 becomes released, and the piston 26 together with the piston 26 The rod 18 moves backward and the clamp arm 14 is opened.

If the clamp arm 14 is to be set to the closed state when returning the transport carriage 10 with the workpiece W removed to the first stage, supply compressed air to the forward fluid chamber 27 a. The piston rod 18 moves forward.

FIG. 6 is an enlarged front view showing another type of clamping device. In FIG. 6, members common to those shown in FIG. 2 are denoted by the same reference numerals.

While the clamp device 12 shown in FIG. 2 causes the clamp arm 14 to be fastened by the forward movement of the piston opening 18, ie, the pressing movement, the clamp device 12 a shown in FIG. The clamp arm 14 is fastened by the backward movement, ie, the pulling movement of the biston mouth pad 18. In the hydraulic cylinder 16a for performing such a clamping operation, the brake cylinder 24 is provided at the rear end of the cylinder body 23.

The brake sut 40 mounted in the inside of the bar 4 restricts the return direction of the piston rod 18, that is, the movement of the piston rod 18 in the forward direction.

. The taper rod applies a load to the brake unit 40 in the backward direction. Thus, the hydraulic cylinder 16a shown in Fig. 6 The clamp arm 14 is closed by the reciprocating movement of the ton rod 18. When the clamp arm 14 is closed, the clamp arm 14 is retracted to the piston opening 18 in the same manner as in the above-described embodiment. Directional loads can be applied.

The present invention is not limited to the above-described embodiments, but can be variously modified without departing from the gist thereof. For example, the fluid pressure cylinders 16 and 16a are used to clamp panel materials constituting a vehicle body, but the invention is not limited to this, and the piston rod 18 is moved to a predetermined stroke position. The fluid pressure cylinder can be applied to any application as long as a predetermined load is applied to the piston rod 18 even if the supply of fluid pressure to the piston 26 is stopped. it can.

In this fluid pressure cylinder, the pistons 26 are moved by compressed air. However, the pistons 26 may be reciprocated by the pressure of liquid such as hydraulic pressure.

Although this fluid pressure cylinder is used to drive the clamp device 12 provided on the carrier 10, it should also be applied to the case where it is attached to the tip of a robot arm to clamp and convey panel materials. Can be.

In this fluid pressure cylinder, a brake unit 40 which is connected to the piston rod 18 when the lock plate 42 inclines is used as an opening means, but is not limited thereto. The plurality of steel balls that are supported by the holder to restrict the axial movement and contact the outer peripheral surface of the piston rod 18 and the inner peripheral surface that contacts these steel balls are formed in a tapered shape. A force par having an inclined surface at the end is provided, and the taper rod 63 is advanced toward the inclined surface and the cover is moved in the axial direction to be connected to the biston rod 18. ,. Also, a brake metal is provided inside the brake cylinder so as to cover the piston rod 18, and the brake metal is pressed against the piston port 18 to be connected to the piston rod 18.

Industrial applicability INDUSTRIAL APPLICABILITY The present invention can be applied when positioning and fixing a panel material and the like in a manufacturing process of an automobile body and the like constituted by the panel material.

Claims

The scope of the claims

1. A cylinder body having a cylinder tube with an end cover attached to one end and a mouth cover attached to the other end;

A piston which is mounted in the cylinder tube so as to be reciprocally movable in the axial direction, and defines a forward fluid chamber and a backward fluid chamber;

A piston rod that is mounted on the cylinder body so as to be reciprocally movable in the axial direction, is fixed to the piston, and protrudes outward from the rod cover; and is operably provided in a coupled state and a released state with respect to the piston rod. Lock means for restricting return movement of the biston rod when the biston rod moves to a predetermined position;

A plunger member provided to be able to move forward and backward toward the locking means; and a spring member for urging the plunger member to apply a spring force in a forward direction. A load applying means for applying pressure, and when the lip means is in a coupled state, even if the fluid in the fluid chamber is discharged, the load applying means causes the piston to pass through the lip means. A fluid pressure cylinder characterized by applying a load to a mouthpiece.

2. The hydraulic cylinder according to claim 1, wherein the plunger member is provided so as to be able to move forward and backward toward an inclined surface formed in the hook means.

3. The fluid pressure cylinder according to claim 1, wherein the locking means is in a coupled state by the fact that a lip plate having a lip hole through which the piston port penetrates is inclined with respect to the biston rod. A fluid pressure cylinder characterized by the following.

4. A cylinder body having a cylinder tube with an end force par attached to one end and a rod cover attached to the other end;

A piston which is mounted in the cylinder tube so as to be reciprocally movable in the axial direction, and defines a forward fluid chamber and a backward fluid chamber; A piston rod, which is attached to the cylinder body so as to be able to reciprocate in the axial direction, is fixed to the piston, and projects outward from the lid cover, and is connected to the piston rod; A clamp arm for clamping the work by retreating;

Lock means operably provided in a coupled state and a released state with respect to the piston port, and for restricting a return movement of the biston rod when the biston rod moves to a predetermined position;

A plunger member movably movable toward and away from the hook means; and a spring member for urging the plunger member to apply a spring force in an advance direction. And a load applying means for applying a load, wherein the lock means and the piston rod are provided by the load applying means even when the fluid in the fluid chamber is discharged when the lip means is in a coupled state. Characterized in that a load is applied to the clamp arm via

5. The clamp device according to claim 4, wherein the plunger member is provided so as to be able to move forward and backward toward an inclined surface formed in the locking means.

6. The clamping device according to claim 4, wherein the locking means is in a connected state by tilting a hook plate having a hook hole through which the biston rod penetrates with respect to the biston rod. Clamp device.