JP4241344B2 - Fluid pressure cylinder - Google Patents

Description

  The present invention relates to a fluid pressure cylinder in which a piston rod is reciprocated by fluid pressure such as air pressure, and more particularly to a technique effective when applied to a fluid pressure cylinder having a lock mechanism.

  An assembly line of an automobile is provided with a plurality of processes for joining panel materials molded in a pressing process by spot welding or the like. These processes include the underbody process for forming the base of the vehicle body, the side body process for forming the side surface of the vehicle body, the main body process for forming the skeleton of the vehicle body by joining the underbody and the side body, and the main body. There is a metal line process for assembling doors and hoods.

  As a method of moving the panel material between work stages that perform each process on the body assembly line, a handling device that fixes the panel material with an insertion clamp or the like is installed at the tip of a transfer actuator such as a robot arm, and the panel material is Many fixed handling devices are moved by operating the arm.

  Some handling devices are equipped with cylinder actuators that move the insertion clamps forward and backward so that they can be fixed to various types of members that have different shapes. In particular, this cylinder actuator collides with the insertion clamp and the panel material. Even so, a fluid pressure cylinder using air pressure is often used to absorb the impact.

  However, the lock mechanism provided in the fluid pressure cylinder described above is configured to lock only the movement of the piston rod toward either the forward direction or the backward direction. Therefore, even if the fluid cylinder is extended and the insertion clamp is pushed into the panel material and fixed, and the piston rod position is locked at that time, if the panel material is moved together with the handling device by driving the robot arm, the piston rod However, the fixed position of the panel material is shifted from the lock position, and the panel material cannot be accurately positioned, making it difficult to perform highly accurate assembly work.

  An object of the present invention is to provide a fluid pressure cylinder capable of fixing the axial position of a piston rod in both forward and backward directions.

  The fluid pressure cylinder of the present invention includes a cylinder body that houses a piston rod and a main piston, and is divided into a forward pressure chamber and a backward pressure chamber by the main piston, and an inclined surface that is assembled to the piston rod. Two lock units provided, and two lock pistons each having a pressing surface and housed in the lock piston housing portion so as to be capable of reciprocating between a forward limit position approaching the piston rod and a retreat limit position separating from each other. The inclined surface of one lock unit is in contact with the side surface on the piston rod advance side of the pressing surface of one lock piston, and the other lock unit is on the side surface on the piston rod retreat side of the press surface of the other lock piston. It is characterized by the fact that the inclined surfaces are in contact with each other.

  The fluid pressure cylinder of the present invention is characterized in that the two lock units are installed such that their inclined surfaces face each other in the axial direction.

  In the fluid pressure cylinder of the present invention, the two lock units operate in a fastening state in which the two lock units are respectively fastened to the piston rod and a release state in which the fastening is released. Is an operating position for switching to a fastening state, and a retreating position for switching the lock unit to a released state at the retreat limit position.

  In the fluid pressure cylinder of the present invention, the two lock pistons each divide the inside of the lock piston housing portion into a lock pressure chamber and a lock release pressure chamber, and communicate with each lock pressure chamber to the lock unit via the lock piston. A lock fluid supply path for guiding a lock fluid to which thrust is applied, a lock release fluid supply path for communicating a lock release fluid that communicates with each lock release pressure chamber and releases a thrust from the lock unit via a lock piston, A lock spring member that is incorporated in the lock pressure chamber and applies a thrust of the spring to the lock unit via the lock piston, and the thrust of the lock fluid and the thrust of the lock spring member are coupled to the piston rod via the lock unit. It is characterized by adding in the axial direction.

  The fluid pressure cylinder of the present invention is characterized in that the lock fluid supply path connects two lock pressure chambers in series and guides the lock fluid in order.

  In the fluid pressure cylinder of the present invention, the unlocking fluid supply path supplies and discharges fluid between the outside and the retreat pressure chamber is locked via an internal check valve and an internal throttle arranged in parallel. It is connected to the release fluid supply path, and the internal check valve is installed in such a manner that the fluid is passed in the direction of guiding from the reverse pressure chamber to the unlocking fluid supply path and closed in the reverse direction. To do.

  The fluid pressure cylinder of the present invention is characterized in that the unlocking fluid supply path communicates with the forward pressure chamber, and the lock fluid supply path communicates with the backward pressure chamber.

  The fluid pressure cylinder of the present invention has a plunger that is slidably mounted on the lock piston and opens the lock fluid supply path into the lock pressure chamber after the lock piston moves toward the operating position with a predetermined stroke. After applying the thrust of the locking spring member to the piston, the thrust of the locking fluid is applied together.

  The fluid pressure cylinder of the present invention is characterized in that the two lock pistons reciprocate in the radial direction of the piston rod and transmit thrust to the inclined surface of the lock unit via a pressing surface formed on the lock piston. .

  The fluid pressure cylinder of the present invention includes a ball in which two lock units are respectively disposed on the outer peripheral surface of the piston rod, and a lock sleeve that is reciprocally mounted in the axial direction of the piston rod and fastened to the piston rod via the ball. It is characterized by providing.

  According to the present invention, two lock pistons and two lock units are provided, and the two lock units are installed in opposite directions in the axial direction so as to be pressed and fixed to each other. Since the stored distortion force is stored so as to cancel each other in opposite directions, the axial position of the piston rod can be fastened and fixed in both the forward and backward directions.

  According to the present invention, the two lock units are installed in directions in which the inclined surfaces face each other in the axial direction, so that the distortion forces stored in the two lock units cancel each other in opposite directions. Therefore, the axial position of the piston rod can be fastened and fixed more reliably in both the forward and backward directions.

  According to the present invention, the two lock units are operated so as to switch between the engagement and the release of the piston rod by the forward and backward movement of the lock piston, respectively, thereby fastening and fixing the piston rod at an arbitrary axial position. Can do.

  According to the present invention, the locking force in the lock pressure chamber, that is, the thrust generated by the compressed air and the thrust of the locking spring member are used to switch the two lock units to the fastening state, so that the fastening force of the lock unit is reduced. The spring force from the locking spring member can be set low without causing it.

  According to the present invention, the two lock pressure chambers are connected in series via the lock fluid supply passage, and compressed air is supplied in order, thereby providing a time difference in the fastening operation of the two lock units. The play can be removed in sequence for the two lock units.

  According to the present invention, the reverse pressure chamber is connected to the unlocking fluid supply path via the internal check valve and the internal throttle arranged in parallel, so that the piston rod starts to move backward. The fastening state of the two lock units can be released.

  According to the present invention, when the unlocking fluid supply path is connected to the forward pressure chamber and the lock fluid supply path is connected to the backward pressure chamber, the backward movement of the piston rod is limited when By switching the two lock units to the engaged state, the axial position of the piston rod can be reliably fixed in both the forward and backward directions.

  According to the present invention, the thrust generated by the compressed air 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. Can be stored.

  According to the present invention, since the thrust is transmitted by the sliding contact between the pressing surface and the inclined surface between the lock piston and the lock unit that reciprocate in directions orthogonal to each other, the fastening operation can be performed smoothly and reliably.

  According to the present invention, the lock unit is fastened by pressing a ball disposed on the outer peripheral surface of the piston rod against the outer peripheral surface of the piston rod by a lock sleeve mounted so as to be reciprocally movable in the axial direction of the piston rod. Can be fastened and smoothly.

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

  FIG. 1 is a view showing a part of a vehicle body assembly line in which a panel material constituting an automobile body is conveyed by a robot arm equipped with a handling device. The robot arm 1 is a transfer device that controls the position movement and posture of the arm tip by connecting a plurality of arms 2 with a large number of movable joints 3 and controlling the angle between them. The handling device 4 has a pedestal 5 that can be attached to the distal end of the arm, and a plurality of insertion clamps 6 that can be locked and fixed by inserting locking pins into the fixing holes of the panel material W are installed on the pedestal 5. Thus, several insertion clamps 6 are installed so as to be movable back and forth from the pedestal 5 via the fluid pressure cylinder 11. As described above, since several insertion clamps 6 can be moved forward and backward from the pedestal 5, various types of panel members W can be fixed corresponding to different shapes.

  The robot arm 1 moves the handling device 4 from the first work stage S1 to the final work stage Sn. In the first work stage S 1, the panel material constituting the vehicle body is fixed to the handling device 4 as a work W, and in the final work stage Sn, the work W for which a predetermined assembly work has been completed is removed from the handling device 4.

  As a procedure for fixing the workpiece W by the handling device 4 on the work stage S1, first, the fluid pressure cylinder 11 is pulled in, and all the insertion clamps 6 are positioned at the retreat limit position, and the workpiece W on the side closer to the base 5 is fixed. The insertion clamp 6 is moved forward in order from the hole and fixed. When the fluid pressure cylinder 11 is extended and each insertion clamp 6 is inserted and fixed, the insertion clamp 6 moves forward at the timing when the cylinder stopper 7 provided on the fluid pressure cylinder 11 contacts the stage stopper 8 provided on the stage side. The movement is stopped. 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 with the fluid pressure cylinder 11. An arrangement of insertion clamps can be provided in the handling device 4 so that the fluid pressure cylinder 11 can move forward and backward.

  FIG. 2 is a view showing a fluid pressure cylinder according to the first embodiment of the present invention, in which FIG. 2 (A) is a left side view thereof, FIG. 2 (B) is a plan view thereof, and FIG. It is the right view. In FIG. 2, a fluid pressure cylinder 11 is roughly composed of a substantially rectangular cylinder-shaped cylinder block 12, a substantially rectangular parallelepiped-shaped lock guide block 13 installed on one end face of the cylinder block 12, and the lock guide block 13. A piston rod 14 inserted through the cylinder block 12 so as to be reciprocally movable, and two auxiliary rods 15 penetrating the lock guide block 13 so as to be reciprocally movable in parallel with the piston rod 14; A flange 16 coupled to the ends of the piston rod 14 and the two auxiliary rods 15, and two lock piston accommodating portions 17 installed in an arrangement extending in the radial direction of the piston rod 14 from one side surface of the lock guide block 13. , 117.

  As will be described later, the lock guide block 13 includes a lock unit housing portion around the internal piston rod 14 and also functions as a guide block that supports the two auxiliary rods 15 in a reciprocating manner. As shown in FIG. 2B, the lock guide block 13 is formed with an installation screw hole 19 for installation in the component handling device 4 described above.

  The fluid pressure cylinder 11 is coupled to the piston rod 14 and the piston rod 14 by supplying compressed air to one of the two supply / discharge ports 20 and 21 formed in the cylinder block 12 and discharging air from the other. The flange 16 is moved forward and backward, and compressed air is supplied to the fixing supply / exhaust port 61 formed in the lock guide block 13, thereby moving the piston rod 14 and the flange 16 in either the forward direction or the backward direction. It can be fixed even against it.

  3 is an axial cross-sectional view of the fluid pressure cylinder 11 taken along line XX corresponding to the axial center of the piston rod 14 in FIG. Hereinafter, for convenience of explanation, the direction in which the lock piston accommodating portions 17 and 117 extend from the side surface of the lock guide block 13 is an upward direction, and the opposite direction is the downward direction.

  As shown in FIG. 3, the cylinder block 12 is a cylindrical body in which a piston accommodation hole 24 for accommodating the main piston 23 in a reciprocating manner in the axial direction is formed, and a central rod cover is provided between the cylinder block 12 and the lock guide block 13. A plug 26 is attached to the end of the cylinder block 12 on the opposite side so as to close the piston accommodation hole 24 and fixed by a snap ring 27. An internal space of the piston accommodation hole 24 closed by the central rod cover 25 and the plug 26 forms a cylinder chamber 28.

  Inside the lock guide block 13, a lock unit accommodation hole 30 for accommodating two lock units 29, 129 is formed around the piston rod 14, and the end on the flange 16 side closes the lock unit accommodation hole 30. Thus, the tip rod cover 31 is attached and fixed by a snap ring 32. The lock unit accommodation hole 30 closed by the tip rod cover 31 and the central rod cover 25 forms a lock unit accommodation portion 33. A cylinder body is formed by the cylinder block 12 and the lock guide block 13 that form the cylinder chamber 28 and the lock unit housing portion 33 therein, and the two lock piston housing portions 17 and 117.

  The inside of the cylinder chamber 28 is divided into a forward pressure chamber 34 and a backward pressure chamber 35 by the main piston 23 housed in the cylinder block 12. The cylinder block 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 a guide block 13. It communicates with the lock unit accommodating portion 33 via the inner supply / discharge path 22.

  The central rod cover 25 is provided with an internal check valve 59 and an internal throttle 60, which are connected in parallel to each other so as to connect the retreat pressure chamber 35 and the lock unit housing portion 33. The internal check valve 59 is disposed in such a manner that it allows compressed air to pass in the direction of guiding from the retreat pressure chamber 35 to the lock unit housing portion 33 and closes in the reverse direction.

  When compressed air, which is a fluid, is supplied from the forward supply / discharge port 20 to the forward pressure chamber 34, the main piston 23 is pressed by the compressed air and moves forward toward the central rod cover 25. When compressed air is supplied to the retreat supply / discharge port 21, the compressed air is supplied to the retreat pressure chamber 35 via the internal throttle 60 while increasing the pressure in the lock unit housing portion 33 as will be described in detail later. The piston 23 moves backward toward the plug 26.

  The main piston 23 includes an annular first disk 23a provided with a sealing material 23c and a second disk 23b, and a female screw 23e is formed on the inner peripheral surface of the first disk 23a. An annular magnet 23f is sandwiched between the first disk 23a and the second disk 23b, and the position of the main piston 23 can be detected by a sensor (not shown) provided on the cylinder block 12 via the magnet 23f. It is like that.

  Further, the piston rod 14 having the male screw 14a formed at one end is screwed to the first disk 23a of the main piston 23 via the male screw 14a, and penetrates the through hole 25a of the central rod cover 25 so as to cover the tip rod cover. 31 is supported so that it can reciprocate. The piston rod 14 fixed to the main piston 23 moves in the axial direction integrally with the main piston 23 by supply / discharge control of compressed air to and from the forward pressure chamber 34 and the reverse pressure chamber 35.

  The two lock units 29 and 129 are accommodated in the lock unit accommodating portion 33 so as to face each other at both end positions on the distal end rod cover 31 side (flange 16 side) and the central rod cover 25 side (cylinder block 12 side). Has been. Each of the lock units 29 and 129 has a steel ball 36 as a plurality of balls arranged on the outer periphery of the piston rod 14, and a cylindrical holding unit that holds the plurality of steel balls 36 and penetrates the piston rod 14. The retainer 37 is capable of reciprocating with respect to the piston rod 14. Each of the lock units 29 and 129 includes a lock sleeve 38 having an inner taper surface 38 a formed on the inner periphery thereof on the outer peripheral side of the retainer 37. The lock sleeve 38 can reciprocate in the lock unit accommodation hole 30. Is housed. As described above, the plurality of steel balls 36 are arranged between the outer peripheral surface of the piston rod 14 and the inner tapered 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 steel ball 36 is pressed against the piston rod 14 to fasten the piston rod 14 and the lock sleeve 38 and a release state in which the pressure on the piston rod 14 is released to release the fastening.

  Each of the lock units 29 and 129 includes a bottomed cylindrical spring receiving member 39 having a flange portion 39 a between the lock sleeve 38 and the central rod cover 25 or the tip rod cover 31. A release spring member 40 is provided between the flange portion 39a and the rod covers 25, 31. The release spring member 40 biases the lock sleeve 38 in the release direction via a flange portion 39a that abuts the lock sleeve 38. That is, the two release spring members 40 urge the lock sleeve 38 in the direction away from the rod covers 25 and 31, respectively. Further, a holding spring member 41 is provided between the bottom of the spring receiving member 39 and the cage 37, and these two holding spring members 41 are urged in a direction to bring the cage 37 close to each other. To do.

  A cylindrical positioning sleeve 42 penetrates the piston rod 14 and is mounted on the outer periphery of the positioning sleeve 42 so as to be reciprocally movable. The positioning sleeve 42 serves as a stopper for restricting axial movement of the retainer 37 and the steel ball 36 by the retaining spring member 41 at a predetermined position.

  The flange-side lock piston accommodating portion 17 located on the flange 16 side and the cylinder-side lock piston accommodating portion 117 located on the cylinder block 12 side are respectively formed by a cylinder 43 and a head cover 44 that closes the cylinder 43, and each has an internal configuration. Are basically the same, and only the passage of compressed air formed inside the cylinder 43 and the head cover 44 is different as will be described later.

  Lock cylinders 45 and 145 are accommodated in the respective cylinders 43, and both the lock pistons 45 and 145 are reciprocally movable in the radial direction with respect to the piston rod 14. In the lock piston accommodating portions 17 and 117, the thrust of the fluid is opposed to the lock pressure chamber 47 in which the lock spring member 46 is accommodated by the lock pistons 45 and 145 and the spring force that is the thrust of the lock spring member 46. Is divided into a lock release pressure chamber 48 for applying to the lock pistons 45 and 145.

  Each lock piston 45, 145 is formed in a cylindrical shape with a bottom having a flange portion 45a, and includes a spring accommodating hole 45b and a cylinder hole 45c. An annular spring receiving member 49 is incorporated in the spring accommodating hole 45 b, and the locking spring member 46 is held in the lock pressure chamber 47 by the spring receiving member 49 and the head cover 44.

  Further, in only one lock piston 45 accommodated in the flange side lock piston accommodating portion 17, a plunger 50 including a piston portion 50a and a rod portion 50b is incorporated in the cylinder hole 45c so as to be reciprocally movable. A plunger spring member 51 is incorporated between the end surface of the portion 50a and the bottom surface of the cylinder hole 45c. The plunger 50 is biased in a direction approaching the head cover 44 by the spring force of the plunger spring member 51, and movement in this direction is restricted by the piston portion 50 a coming into contact with the spring receiving member 49. That is, the spring receiving member 49 in the lock piston accommodating portion 17 also functions as a stopper for restricting the axial movement of the plunger 50 with a predetermined stroke.

  Fluid introduction holes 52 and 152 for guiding compressed air, which is a lock fluid, are formed in the lock pressure chamber 47 at the substantially central portion of the head cover 44 that forms the lock piston accommodating portions 17 and 117, and flanges are formed. A fluid discharge hole 53 for discharging compressed air from the lock pressure chamber 47 is formed in the head cover 44 of the side lock piston accommodating portion 17.

  As shown in FIG. 3, the fluid introduction hole 52 and the plunger 50 are incorporated substantially concentrically, and the plunger 50 moves in the ascending direction (the direction away from the piston rod 14) in the figure, so that the plunger 50 is moved to the head cover. 44, the fluid introduction hole 52 and the lock pressure chamber 47 are blocked by the rod portion 50b of the plunger 50, and the lock piston 45 moves in the downward direction (the direction approaching the piston rod 14) in the figure. Accordingly, when the plunger 50 is separated from the head cover 44, the fluid introduction hole 52 and the lock pressure chamber 47 are in communication with each other. 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 maintained by bringing the tip of the rod portion 50b of the plunger 50 into contact with the valve seat 54. Be drunk.

  Each unlocking pressure chamber 48 communicates with the lock unit accommodating portion 33 through a communication passage 55. When compressed air is supplied to the unlocking pressure chamber 48 as described later, the lock pistons 45 and 145 are connected to the piston rod 14. Move upward toward the retracted position away from Here, particularly in the process of the upward movement of the lock piston 45, the rod portion 50b of the plunger 50 protrudes from the lock piston 45 until the flange portion 45a of the lock piston 45 contacts the head cover 44. After the 50 rod portions 50 b come into contact with the valve seat 54 of the head cover 44, the flange portion 45 a of the lock piston 45 comes into contact with the head cover 44. When the lock piston 45 moves upward until it comes into contact with the head cover 44, the plunger spring member 51 is compressed, and a predetermined clearance C1 is formed between the piston portion 50b and the spring receiving member 49.

  When the two lock pistons 45 and 145 are moved upward, the air in the lock pressure chamber 47 is exhausted from the valve seat 54 through the fluid introduction holes 52 and 152. In the piston 45, the fluid introduction hole 52 is blocked by the contact between the rod portion 50 b of the plunger 50 and the valve seat 54 during the ascent. For this reason, the U packing 56 provided in the piston portion 50b of the plunger 50 is mounted in a direction allowing air flow in the downward direction, and the air in the lock pressure chamber 47 is in contact with the rod portion 50b of the plunger 50 and the valve seat. Even after contacting 54, air can be discharged in the downward direction from between the U-packing 56 and the cylinder hole 45c, and through the through-hole 50c formed at the center of the plunger 50. The fluid can be exhausted from the fluid introduction hole 52.

  On the other hand, when the compressed air in each unlocking pressure chamber 48 is discharged through the communication passage 55, the lock pistons 45, 145 approach the piston rod 14 by the spring force from the lock spring member 46 and contact the lock sleeve 38. Move downward toward the operating position. In the process in which the lock piston 45 including the plunger 50 moves downward, the plunger 50 is urged in the upward direction by the spring force. Therefore, after the lock piston 45 is separated from the head cover 44, the piston portion 50b of the plunger 50 is moved. After contact with the spring receiving member 49, the rod portion 50 b of the plunger 50 is separated from the head cover 44. That is, even if the downward movement of the lock piston 45 is started, the rod portion 50b of the plunger 50 remains in contact with the valve seat 54 of the head cover 44 until the lock piston 45 is lowered by a predetermined stroke (corresponding to the clearance C1). Will do.

  In the two lock piston housing portions 17 and 117 on the flange 16 side and the cylinder block 12 side, tapered rod portions 45e each having a lock taper surface 45d as a pressing surface are formed at the tips of the lock pistons 45 and 145 that reciprocate. The taper angle of the lock taper surface 45d is an acute angle of about 30 °. To correspond to these lock taper surfaces 45d, outer taper surfaces 38b that are inclined surfaces are also formed on the end surfaces of the two lock sleeves 38 facing each other, and the taper angle of the outer taper surfaces 38b is as follows. The obtuse angle is about 150 °.

  When the lock pistons 45 and 145 move downward toward the lock sleeve 38, the lock taper surface 45d (pressing surface) of each taper rod portion 45e contacts with the outer taper surface 38b (inclined surface) of the lock sleeve 38, respectively. To do. As a corresponding relationship at this time, an outer taper surface 38b (of the lock unit 38 on the flange 16 side) on the side of the piston rod advance side of the lock taper surface 45d (pressing surface) of the lock piston 45 in the flange side lock piston housing portion 17 ( And the outer taper surface of the lock unit 38 on the cylinder block 12 side is in contact with the side surface on the piston rod retraction side of the lock taper surface 45d (pressing surface) of the lock piston 145 in the cylinder side lock piston housing 117. 38b (inclined surface) comes into contact.

  In each lock unit 29, 129, each lock sleeve 38 is pushed toward the flange 16 side or the cylinder block 12 side via the outer tapered surface 38b that comes into contact with each other, and the two lock units 29, 129 are fastened. On the other hand, when the lock pistons 45 and 145 move upward, the lock sleeves 38 are pushed in the directions approaching each other by the spring force of the release spring member 40, so that the two lock units 29 and 129 are released. .

  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 lock piston 45. A screw member 57 is attached to the fluid introduction holes 52 and 152 formed in the head cover 44 as a plug for blocking the fluid introduction holes 52 and 152 from the outside, and the lock pistons 45 and 145 extend from the cylinder hole 45c. A screw hole 45f is formed. When manually moving the lock pistons 45 and 145, a rod member (not shown) having a male screw formed at the tip is inserted into the fluid introduction holes 52 and 152 from the outside with the screw member 57 removed, and a plunger 50 is provided. On the other hand, it is screwed with the screw hole 45f through the through hole 50c of the plunger 50. As a result, both the lock pistons 45 and 145 can be moved up and down from the outside via the rod member, and the lock units 29 and 129 can be manually switched between the release state and the fastening state. it can.

  Next, a supply flow path for supplying compressed air to the forward pressure chamber 34, the reverse pressure chamber 35, each lock pressure chamber 47, and each lock release pressure chamber 48 will be described. As shown in FIG. 3, an annular rubber damper 23d having an outer diameter smaller than that of each of the disks 23a and 23b is attached to the rear end face of the first piston disk 23a of the main piston 23 and the front end face of the second piston disk 23b. Even when the main piston 23 is located in the retreat limit position or the advance limit position in the cylinder chamber 28 and the rubber damper 23d is in contact with the plug 26 or the central rod cover 25, there is a gap (that is, the minimum) on the outer periphery of the rubber damper 23d. The forward pressure chamber 34 and the reverse pressure chamber 35) having the capacity are formed.

  The forward supply / exhaust port 20 communicating with the forward pressure chamber 34 has a gap (minimum forward advancement) between the first disk 23a and the plug 26 when the main piston 23 is positioned at the retreat limit position. The pressure chamber 34) is formed so as to communicate with the pressure chamber 34), and the pressure receiving area on the main piston 23 in the forward pressure chamber 34 can always be secured. Similarly, the internal throttle 60 that communicates with the retreat pressure chamber 35 has a gap between the second disk 23b and the central rod cover 25 when the main piston 23 is located at the forward limit position (minimum retraction use). The pressure chamber 35) is formed so as to communicate with the pressure chamber 35), so that the pressure receiving area on the main piston 23 in the retreat pressure chamber 35 can always be secured. Each supply / discharge port 20, 21 is connected to a compressed air source via a common flow path switching valve, which will be described later, and is compressed to one of the two supply / discharge ports 20, 21 by switching operation of the flow path switching valve. Air is supplied, and compressed air is discharged from the other supply / discharge ports 20 and 21. Therefore, the supply / discharge control of the compressed air to the forward pressure chamber 34 and the reverse pressure chamber 35 can be performed via the supply / discharge ports 20 and 21.

  Further, the through hole 25a of the central rod cover 25 through which the piston rod 14 penetrates has a diameter substantially the same as the outer diameter of the piston rod 14, and the sealing material 25b attached to the inner peripheral surface of the piston rod 14 adheres to the outer periphery of the piston rod 14. Touching. Further, since the 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 retreat supply / discharge port 21 communicates with the entire lock unit housing portion 33. Furthermore, it communicates with the lock release pressure chamber 48 in each lock piston accommodating portion 17, 117 via each communication passage 55. Further, the reverse supply / discharge port 21 is also communicated with the reverse pressure chamber 35 via the lock unit accommodating portion 33 (unlocked fluid supply path) and the internal throttle 60.

  Here, the supply / exhaust passage 22, the lock unit accommodating portion 33 including the communication gap 58, and each communication passage 55 constitute an unlocking fluid supply passage, that is, each unlocking pressure chamber 48 is respectively connected via the unlocking fluid supply passage. The retreat supply / discharge port 21 and the retreat pressure chamber 35 communicate with each other. When compressed air is supplied to the retreat supply / exhaust port 21, the compressed air is first introduced into the lock unit housing portion 33, but the internal check valve 59 of the central rod cover 25 is compressed in the reverse direction. Air does not pass through, but is introduced into the retreat pressure chamber 35 through only the internal throttle 60. However, since the internal throttle 60 has a narrow channel cross-sectional area and a small allowable passage flow rate, a back pressure is generated inside the lock unit accommodating portion 33, that is, the unlocking fluid supply path, and the pressure rises.

  For this reason, the pressure of the unlocking pressure chamber 48 in each lock piston accommodating portion 17, 117 rises before the retreating pressure chamber 35 via each communication passage 55, and the lock piston 45, 145 is raised to the retracted position. Will be moved. Thereafter, the compressed air is sufficiently introduced into the retreat pressure chamber 35 so that the main piston 23 is pushed and moved in the retreat direction. That is, when compressed air is supplied to the reverse supply / discharge port 21, the main piston 23 moves backward after the lock pistons 45, 145 move to the retracted position.

  FIG. 4 is a diagram for simply explaining a fluid pressure circuit to which the fluid pressure cylinder 11 of the present embodiment is connected and a path configuration for supplying compressed air to each lock pressure chamber 47 and each lock release pressure chamber 48. . 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 is connected to the forward fluid flow path 67 and the backward supply / discharge port 21 connected to the forward supply / discharge port 20. The retreating fluid flow path 68 to be connected is connected to the two output ports 66b and 66c of the flow path switching valve 66, respectively. In addition, an external check valve 67a is provided at an intermediate position of the forward fluid passage 67 in an arrangement that allows passage of air in a direction from the passage switching valve 66 toward the forward supply / discharge port 20. An external throttle 67b is connected in parallel to the installation check valve 67a.

  The fixing supply / discharge port 61 is connected to the forward fluid flow path 67 on the flow path switching valve 66 side from the external check valve 67a through the fixing fluid flow path 69. By switching between two switching positions, the flow path switching valve 66 connects one of the forward fluid flow path 67 and the backward fluid flow path 68 to the compressed air source 65 to supply the compressed air, and the other is connected to the outside. It is open to the atmosphere and discharges compressed air.

  Compressed air (lock fluid) supplied via a fixing supply / exhaust port 61 formed in the lock guide block 13 is connected to a flange side lock piston via a fluid introduction passage 62 (not shown in FIG. 3). The fluid is supplied to the fluid introduction hole 52 of the accommodating portion 17. The fluid discharge hole 53 formed in the head cover 44 of the flange side lock piston accommodating portion 17 is connected to the fluid introduction hole 152 of the cylinder side lock piston accommodating portion 117 via a fluid communication path 63 (not shown in FIG. 3). The compressed air is supplied from the lock pressure chamber 47 of the flange side lock piston accommodating portion 17 in communication.

  That is, by supplying compressed air to the fixing supply / exhaust port 61, compressed air is supplied to the lock pressure chamber 47 in the flange side lock piston accommodating portion 17 via the fluid introduction path 62 and the fluid introduction hole 52, and the lock piston. 45 can be moved down to the operating position. Further, compressed air is supplied from the lock pressure chamber 47 in the flange side lock piston accommodating portion 17 to the fluid introduction hole 152 and the lock pressure chamber 47 in the cylinder side lock piston accommodating portion 117 through the fluid discharge hole 53 and the fluid communication path 63. The lock piston 145 can be moved downward to the operating position by supplying.

  The fixing supply / discharge port 61, the fluid introduction path 62, the fluid introduction hole 52, the fluid discharge hole 53, the fluid communication path 63, and the fluid introduction hole 152 constitute a lock fluid supply path throughout, that is, supply of the lock fluid. The passage is configured such that two lock pressure chambers 47 are connected in series in the order of the cylinder side and then the rod side, and compressed air can be supplied to each.

  Next, the operation of the fluid pressure cylinder 11 will be described. 5 (A) to 6 (B) are enlarged sectional views showing a part of the fluid pressure cylinder 11, and FIG. 5 (A), FIG. 5 (B), FIG. 6 (A), and FIG. 6 (B). The process in which the lock unit 29 on the flange 16 side operates from the released state to the fastened state in this order.

  First, in the lock unit 29 on the flange 16 side including the plunger 50, the piston rod 14 is moved from the state where the main piston 23 is disposed at the retreat limit position on the plug 26 side, that is, the piston rod 14 is drawn into the cylinder body. An operation when the main piston 23 is moved forward will be described.

  In a state where the main piston 23 is disposed at the retreat limit position, the compressed air is supplied from the retreat supply / exhaust port 21 to the lock unit accommodating portion 33 and the lock release pressure chamber 48 via the retreat pressure chamber 35. ing. The compressed air applied to the lock release pressure chamber 48 applies a pressing force to the lock piston 45 in the upward direction in which the lock spring member 46 is compressed, and the lock piston 45 moves upward away from the lock sleeve 38. The pressure receiving area of the lock piston 45 that receives the air pressure supplied to the lock release pressure chamber 48 is set to an area sufficient to generate a pressing force against the spring force from the lock spring member 46.

  When the lock piston 45 moves upward, contact between the lock piston 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. When the backward movement is completed, a predetermined clearance C2 is formed between the end surface of the lock sleeve 38 and the end surface of the distal end rod cover 31 as shown in FIG. Thus, when the lock sleeve 38 is operated to the release position, a predetermined clearance C3 is provided between the inner tapered surface 38a of the lock sleeve 38 and the steel ball 36, so that the lock unit 29 has the steel ball 36 connected to the piston rod. 14 is in a released state without being pressed by 14.

  Under such a state, when compressed air is supplied to the forward pressure chamber 34 from the forward supply / discharge port 20 and the compressed air in the backward pressure chamber 35 is discharged, the main piston 23 and the piston rod 14 Is moved in the forward direction indicated by arrow a in FIG. At this time, the air in the retreat pressure chamber 35 is discharged to the lock unit housing portion 33 through the internal check valve 59 and the internal throttle 60 as the main piston 23 moves, and further through the supply / discharge passage 22. The air is discharged from the retreating supply / discharge port 21 to the retreating fluid flow path 68. At the same time, the air in the lock unit accommodating portion 33 is compressed by the external throttle 68a provided in the retreating fluid flow path 68, and the pressure increases. Will do. That is, a back pressure (pressing air pressure by the unlocking fluid) corresponding to the moving speed of the main piston 23 is generated in the unlocking fluid supply path including the lock unit accommodating portion 33.

  Since the back pressure generated in the lock unit housing portion 33 is applied to the lock release pressure chamber 48 via the communication passage 55, a pressing force is applied to the lock piston 45 in the upward direction that compresses the lock spring member 46. The lock piston 45 is held in the retracted position. The pressure receiving area of the lock piston 45 that receives the back pressure generated in the lock unit housing portion 33 is set to an area sufficient to generate a pressing force against the spring force from the lock spring member 46 even by the back pressure. Has been. That is, when the piston rod 14 is moved in the forward direction by supplying compressed air to the forward pressure chamber 34 from the forward supply / discharge port 20, the two lock units 29 and 129 are held in the released state. The piston rod 14 can be moved forward.

  Although the case where the piston rod 14 is moved forward in the direction of the arrow a by supplying compressed air to the forward pressure chamber 34 has been described, the compressed air is supplied to the backward pressure chamber 35 and the forward pressure chamber 34 is supplied. Even if the piston rod 14 is moved backward in the direction of the arrow b by discharging the compressed air inside, the lock is applied because the back pressure is applied to the unlocking pressure chamber 48 by the internal throttle 60 as described above. The unit 29 is released.

  Thus, when the piston rod 14 is moved forward and backward, the lock unit 29 can be released by the back pressure generated by the internal throttle 59 and the external throttle 68a, and the piston rod 14 is moved forward and backward. Permissible.

  Next, an operation of switching the lock unit 29 on the flange 16 side to the fastening state will be described. When the piston rod 14 and the main piston 23 are stopped, that is, when the forward movement of the piston rod 14 is restricted, or when the supply of compressed air to the reverse pressure chamber 35 is stopped, the lock unit 29 is fastened. Switch to state.

  First, the forward movement of the piston rod 14 is restricted, such as when the main piston 23 is positioned at the forward limit position, or when the cylinder stopper 7 contacts the stage stopper 8 in use in the handling device 4 described above. The case where the main piston 23 stops will be described. First, while the compressed air source 65 is connected to the forward fluid passage 67 and the piston rod 14 is moving forward, it is also compressed to the stationary supply / discharge port 61 via the stationary fluid passage 69. Air is being supplied. In the fluid introduction hole 52 opened to the lock pressure chamber 47, the lock piston 45 is moved up to the retracted position, that is, the fluid introduction hole 52 and the lock pressure chamber 47 are blocked by the plunger 50. Compressed air is supplied from the fluid introduction path 62. At this time, since the plunger 50 is provided with the through hole 50c in the center of the shaft, the pressure by the compressed air from the fluid introduction hole 52 is not received in the downward direction, and the fluid introduction hole 52 and the lock pressure chamber 47 are shut off. Is securely held.

  When the main piston 23 stops, the air in the lock unit housing portion 33 is discharged from the flow path switching valve 66 without being compressed, so that the back pressure in the lock unit housing portion 33 gradually decreases. The upward pressing force applied to the lock piston 45 in opposition to the spring force from the locking spring member 46 decreases as the back pressure decreases. That is, as shown in FIG. 5B, when the pressing force for raising the lock piston 45 falls below a predetermined pressing force, the lock piston 45 is biased in the downward direction by the spring force from the locking spring member 46, The lock sleeve 38 moves downward while being pushed toward the fastening position.

  At this time, since the plunger 50 is biased in the upward direction by the plunger spring member 51, the contact state between the rod portion 50b of the plunger 50 and the valve seat 54 is maintained even when the lock piston 45 starts to move downward. . That is, since the shutoff state between the fluid introduction path 62 and the lock pressure chamber 47 is continued, the lock piston 45 is urged in the downward direction only by the spring force. Although the lock pressure chamber 47 is negatively moved by the downward movement of the lock piston 45, the spring force of the lock spring member 46 is set so as to continue the downward movement of the lock piston 45 against this negative pressure. Has been.

  When the lock piston 45 moves in a downward direction with a predetermined stroke (for example, 2 mm) by the spring force of the lock spring member 46, the lock sleeve 38 moves in a forward direction with a predetermined stroke (for example, 0. 8mm). As shown in FIG. 5B, when the lock sleeve 38 moves forward, the clearance C3 provided between the inner tapered surface 38a of the lock sleeve 38 and the steel ball 36 is lost, and the outer peripheral surface of the piston rod 14 is removed. The steel ball 36 comes into contact with the inner tapered surface 38a of the lock sleeve 38 and is sandwiched. That is, the lock piston 45 that moves downward by the spring force of the lock spring member 46 removes the play that has occurred in the lock unit 29 and starts the fastening operation of the lock unit 29.

  As shown in FIG. 5B, when the downward movement of the lock piston 45 reaches a predetermined stroke, the clearance C1 formed between the piston portion 50a of the plunger 50 and the spring receiving member 49 disappears. The piston portion 50a and the spring receiving member 49 are in contact with each other. Subsequently, as shown in FIG. 6 (A), when the lock piston 45 further moves downward, the plunger 50 is pulled down by the lock piston 45, and the plunger 50 and the lock piston 45 integrally start to move downward. . When the rod portion 50 b of the plunger 50 is pulled away 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 path 62 is supplied to the lock pressure chamber 47. The This operation does not require an external switching valve and operates automatically. Therefore, the state shown in FIG. 6A is a state in which thrust by the compressed air (lock fluid) supplied to the lock pressure chamber 47 is applied to the lock piston 45 in addition to the spring force from the lock spring member 46. It has become.

  As shown in FIG. 6B, when the lock piston 45 to which the spring force by the lock spring member 46 and the thrust force by the compressed air are further moved downward, the lock sleeve 38 on the flange 16 side is further moved by the lock piston 45. Pushed in the forward direction. When the clearance between the lock sleeve 38 and the tip 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 moved to the lock sleeve 38. It will be in the fastening state which dig into the piston rod 14. In this way, when the lock 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, so that a predetermined distortion force is applied to the piston rod 14 and the lock unit 29. It is in a stored state.

  Even when the lock unit 29 on the flange 16 side is switched to the fastening state, a predetermined clearance C4 is provided between the lock sleeve 38 and the tip rod cover 31, so that the lock sleeve 38 is further moved forward. Permissible. Then, 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 continue to the piston rod 14 via the lock sleeve 38 in the forward direction. Will be added.

  The spring force from the lock spring member 46 and the thrust 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 outer 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. Further, when the lock sleeve 38 is moved to the fastening position, the taper rod portion 45e enters the retreating direction of the lock sleeve 38. Therefore, until the compressed air is supplied to the lock release pressure chamber 48, the lock unit 29 is securely connected. The fastening state can be maintained.

  Further, even when the spring receiving member 39 moves forward with the movement of the lock sleeve 38, the holding spring member provided between the retainer 37 that holds the steel ball 36 and the bottom of the spring receiving member 39. 41, the retainer 37 can be kept in contact with the positioning sleeve 42. Therefore, the position of the steel ball 36 does not move, and the lock unit 29 can be switched to the fastening state without fail.

  In the above description, the case where the forward movement of the piston rod 14 is restricted and the main piston 23 is stopped has been described, but the case where the main piston 23 is stopped by stopping the supply of compressed air to the forward pressure chamber 34 is described. Even if it exists, the lock unit 29 by the side of the flange 16 can be similarly switched to a fastening state.

  Further, even when the piston rod 14 is moved backward by pushing the flange 16 or the like, the air in the lock unit housing portion 33 is introduced into the pressure chamber 35 for retraction, and the pressure in the lock release pressure chamber 48 is lowered. Thus, the lock unit 29 on the flange 16 side can be switched to the fastening state.

  As described above, when the piston rod 14 moves forward, when the main piston 23 is stopped by limiting the movement of the piston rod 14 or stopping the supply of compressed air to the forward pressure chamber 34, When the pressure in the lock unit housing portion 33 is reduced due to the pressing of the flange 16, the lock unit 29 on the flange 16 side is switched to the fastening state.

  However, the distortion force stored in the piston rod 14 and the lock unit 29 on the flange 16 side is applied only in one direction in the forward direction of the piston rod 14 only by the fastening by the lock unit 29 on the flange 16 side described above. It becomes a state. Therefore, in the handling apparatus 4 shown in FIG. 1, when the cylinder stopper 7 is separated from the stage stopper 8 and the flange 16 is freed, the stored distortion force is released in the forward direction, and the flange 16 and The position of the insertion clamp 6 installed in the head is moved forward (generally about 2 mm). For this reason, the fixing position of the panel material W is shifted together with the insertion clamp 6, so that accurate positioning cannot be performed and assembly work with high accuracy becomes difficult.

  Further, with respect to the lock unit 29 on the flange 16 side, although the steel ball 36 is pressed against the inner taper surface 38a of the lock sleeve 38 against the movement of the piston rod 14 in the backward direction, the fastening state is made more reliable, but in the opposite direction. When the piston rod 14 moves in the forward direction, there is a possibility that the steel ball 36 is disengaged from the lock sleeve 38 and loosened. That is, the lock unit alone is configured to fasten only the movement of the piston rod 14 in one direction. Therefore, the handling device 4 shown in FIG. 1 includes only one lock unit. If it is moved largely together, the fixing position of the panel material W is likely to shift, and this also makes it difficult to assemble with high accuracy.

  With respect to the above problems, the fluid pressure cylinder 11 of the present embodiment is provided with two lock pistons 45 and 145 and two lock units 29 and 129, respectively, and the lock taper surface 45d (pressing surface) of one lock piston 45 is provided. The outer taper surface 38b (inclined surface) of one lock unit 29 is brought into contact with the side surface on the piston rod advance side, and the side surface on the piston rod retreat side of the lock taper surface 45d (pressing surface) of the other lock piston 145. Since the outer taper surface 38b (inclined surface) of the other lock unit 129 is in contact with the other lock unit 129, that is, the two lock units 29 and 129 are installed in directions facing each other in the axial direction and pressed against each other to be fixed. The axial position of the rod 14 can be fixed in both the forward and backward directions. In addition, since the outer tapered surfaces 38b are oriented in the axial direction, the strain forces stored in the two lock units 29 and 129 are stored so as to cancel each other in opposite directions. The position of the piston rod 14 in the axial direction can be securely fastened in both the forward and backward directions.

  Further, the two lock units 29 and 129 are operated so as to switch between fastening and releasing to the piston rod 14 by forward and backward movement of the lock pistons 45 and 145, respectively, so that the piston rod 14 can be moved at an arbitrary axial position. It can be fastened and fixed.

  In addition, since the two lock units 29 and 129 are switched to the fastening state by using the thrust of the lock fluid in the lock pressure chamber 47, that is, the compressed air, and the thrust of the lock spring member 46, the lock units 29 and 129 are switched. The spring force from the locking spring member 46 can be set low without reducing the fastening force. Thereby, size reduction and cost reduction of the fluid pressure cylinder 11 can be achieved.

  Further, the two lock pressure chambers 47 are connected in series via the lock fluid supply passage and are supplied with compressed air in order, so that a time difference is provided in the operation of the two lock pistons 45 and 145 when the fastening operation is performed. Thus, the play in each of the lock units 29 and 129 can be favorably removed as compared with the case where the two lock units 29 and 129 are operated simultaneously since the play is removed in turn. In particular, in the present embodiment, the lock unit 29 on the flange 16 side is actuated first, and then the lock unit 129 on the cylinder side is actuated, so that the piston rod 14 and the flange 16 are advanced as shown in FIG. In the forward-restricted usage mode in which the movement is restricted and the movement is restricted, the play in each of the lock units 29 and 129 can be removed best, and the fixation is possible. Further, the time difference of operation can be changed by changing the length of the fluid communication path 63 between the lock pressure chambers 47.

  In addition, the thrust force generated 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 fastened state. 29, 129 can store distortion force. Accordingly, even after the compressed air is discharged from the lock pressure chamber 47, a high fastening force can be maintained by the distortion force and the spring force.

  In addition, since supply and interruption | blocking of the compressed air with respect to the lock pressure chamber 47 are switched by the plunger 50 according to the stroke of the lock piston 45, after the play of the lock unit 29 is removed, the compressed air in the lock pressure chamber 47 A strong thrust can be transmitted to the piston rod 14 via the lock unit 29. As a result, it is possible to store distortion force in the lock unit 29 without wasting the stroke of the lock piston 45. In the cylinder side lock piston accommodating portion 117, the lock piston 145 can remove the play of the lock units 29 and 129 at the same timing as the lock piston 45, and then the fluid discharge hole 53 of the flange side lock piston accommodating portion 17. Since the compressed air is introduced into the fluid introduction hole 152 of the cylinder side lock piston accommodating portion 117 from the above, the supply and shutoff of the compressed air according to the stroke can be switched without providing the plunger 50.

  Further, when the lock piston 45 is moved upward to the retracted position, the lock pressure chamber 47 and the fluid introduction hole 52 are switched to the cutoff state by the plunger 50 incorporated in the lock piston 45, while the lock piston 45 is moved at a predetermined stroke. When moved downward, the lock pressure chamber 47 and the fluid introduction hole 52 are switched to the communication state. Thereby, even before the lock piston 45 starts to move downward toward the operating position, compressed air may be supplied to the fluid introduction hole 52 in advance in preparation for switching the lock unit 29 to the fastening state. It is possible to increase the degree of freedom of pressure supply control.

  Further, by incorporating the plunger 50 in a reciprocating manner with respect to the lock piston 45, supply of compressed air to the lock pressure chamber 47 in the released state of the lock unit 29 without being affected by the dimensional error or assembly error of each member. Can be stopped reliably. Thereby, the malfunctioning in the release state of the lock unit 29 can be avoided.

  FIG. 7 is an axial sectional view of a fluid pressure cylinder which is a modification of the present embodiment. In FIG. 7, members that are the same as those shown in FIG. 3 are given the same reference numerals, and descriptions thereof are omitted. The fluid pressure cylinder 11 shown in FIG. 3 has two lock piston accommodating portions 17 and 117 arranged in an axial arrangement on the same side, whereas the fluid pressure cylinder 211 shown in FIG. The parts 17 and 117 are installed so as to overlap in the axial direction on the side surfaces opposite to each other.

  Even in such an arrangement, the outer taper surface 38b of one lock unit 29 is brought into contact with the side surface of the lock taper surface 45d of one lock piston 45 on the piston rod advance side, and the lock taper surface 45d of the other lock piston 145 is contacted. Since the outer taper surface 38b of the other lock unit 129 is in contact with the side surface of the piston rod retracting side, the axial position of the piston rod 14 can be fixed in both the forward side and the backward side. Since the two lock units 29 and 129 can be arranged close to each other, the axial length of the entire fluid pressure cylinder 211 can be shortened accordingly.

  Further, when the lock guide block 213 having the lock unit housing portion 233 has a cylindrical shape such as a cylinder, the two lock piston housing portions 17 and 117 are not limited to the opposite side but are arranged at an arbitrary angle around the axis of the piston rod 14. It may be installed in a shifted arrangement.

  Next, a fluid pressure cylinder according to a second embodiment of the present invention will be described. FIG. 8 is an axial sectional view of a fluid pressure cylinder according to the second embodiment. In the fluid pressure cylinder 11 of the first embodiment, the piston rod 14 is moved forward when the forward movement of the piston rod 14 is restricted by the cylinder stopper 7 coming into contact with the stage stopper 8 positioned on the forward side. In contrast to the configuration in which the axial position is fixed in both the forward and backward directions, the fluid pressure cylinder 311 of the present embodiment moves the piston rod 14 when the backward movement of the piston rod 14 is restricted. The structure is fixed in both directions. 8, members that are the same as those shown in FIG. 3 are given the same reference numerals, and descriptions thereof are omitted.

  The fluid pressure cylinder 311 of the present embodiment shown in FIG. 8 is airtight between the pressure chamber 35 for retraction and the lock unit accommodating portion 33 because the central rod cover 325 is not provided with an internal check valve or an internal throttle. The reverse supply / exhaust port 321 is formed so as to directly communicate only with the reverse pressure chamber. The retraction supply / exhaust port 321 is a gap formed between the first disk 23a and the central rod cover 325 on the outer periphery of the rubber damper 23d when the main piston 23 is located at the retreat limit position (the retraction that is minimized). The pressure receiving area on the main piston 23 in the retreating pressure chamber 35 can always be secured.

  A release supply / exhaust port 364 formed on the side surface of the lock guide block 313 and immediately adjacent to the fixing supply / exhaust port 61 communicates with the inside of the lock unit accommodating portion 33, and The lock piston accommodating portions 17 and 117 communicate with the lock release pressure chamber 48.

  FIG. 9 is a diagram for simply explaining a fluid pressure circuit to which the fluid pressure cylinder 311 of this embodiment is connected and a path configuration for supplying compressed air to each lock pressure chamber 47 and each lock release pressure chamber 48. . In FIG. 9, a compressed air source 365 such as a compressor is connected to the input port 366 a of the flow path switching valve 366, and is connected to the forward fluid flow path 367 and the backward supply / discharge port 21 connected to the forward supply / discharge port 20. The retreating fluid flow path 368 to be connected is connected to the two output ports 366b and 366c of the flow path switching valve 366, respectively. In addition, external check valves 367a and 368a having forward directions from the flow path switching valve 366 toward the respective supply / discharge ports 20 and 21 are provided at midway positions of the forward fluid flow path 367 and the reverse fluid flow path 368, respectively. In addition, external throttles 367b and 368b are connected in parallel to the respective external check valves 367a and 368a.

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

  Compressed air supplied through the fixing supply / exhaust port 61 formed in the lock guide block 313 passes through a fluid introduction path 362 (not shown in FIG. 8) of the cylinder side lock piston accommodating portion 117. It is supplied to the fluid introduction hole 152. The fluid discharge hole 153 formed in the head cover 44 of the cylinder side lock piston accommodating portion 117 is connected to the fluid introduction hole 52 of the flange side lock piston accommodating portion 17 via a fluid communication path 363 (not shown in FIG. 8). The compressed air is supplied from the lock pressure chamber 47 of the cylinder side lock piston accommodating portion 117 in communication.

  In other words, by supplying compressed air to the fixing supply / discharge port 61, compressed air is supplied to the lock pressure chamber 47 in the cylinder side lock piston accommodating portion 117 via the fluid introduction path 362 and the fluid introduction hole 152, and the lock piston. 145 can be moved downward to the operating position. Further, compressed air is supplied from the lock pressure chamber 47 in the cylinder side lock piston accommodating portion 117 to the fluid introduction hole 52 and the lock pressure chamber 47 in the flange side lock piston accommodating portion 17 through the fluid discharge hole 153 and the fluid communication path 363. The lock piston 45 can be lowered to the operating position by being supplied.

  The fixing supply / discharge port 61, the fluid introduction path 362, the fluid introduction hole 152, the fluid discharge hole 153, the fluid communication path 363, and the fluid introduction hole 52 constitute a lock fluid supply path throughout, that is, supply of the lock fluid. The passage is configured such that two lock pressure chambers 47 are connected in series in the order of the cylinder side and then the rod side, and compressed air can be supplied to each. Further, the lock fluid supply path communicates with the retreat pressure chamber 35 via the fixing fluid flow path 369 and the retreat fluid flow path 368.

  On the other hand, the unlocking supply / exhaust port 364, the lock unit accommodating portion 33 including the communication gap 58, and the communication passages 55 constitute an unlocking fluid supply path, and the unlocking fluid supply path is the unlocking fluid flow path 370. The forward pressure chamber 34 communicates with the forward fluid passage 367.

  By switching between two switching positions, the channel switching valve 366 connects one of the forward fluid channel 367 and the backward fluid channel 368 to the compressed air source 365 to supply the compressed air and the other to the outside. It is open to the atmosphere and discharges compressed air.

  Next, the operation of the present embodiment will be described. When the compressed air source 365 is connected to the forward fluid flow path 367 by switching the flow path switching valve 366 and the backward fluid flow path 368 is opened to the atmosphere, first, the 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 lock units 29 and 129 are in the fastened state, the volume of the forward pressure chamber 34 is fixed without moving the main piston 23, so that the supplied compressed air is locked. The release fluid channel 370 and the unlocking fluid supply passage are introduced into the unlocking pressure chambers 48 as the releasing fluid, and the fastening of the lock units 29 and 129 is forcibly released. After the fastening is released, the main piston 23 that can reciprocate is pressed by the compressed air and moves forward together with the piston rod 14 and the flange 16.

  During the forward movement, the compressed air pushed out from the retreat pressure chamber 35 passes through the external throttle 368 b and is released into the atmosphere. At this time, the fixing fluid flow path 369 is separated from the retraction fluid flow path 368. The back pressure is not introduced because the connection is made at a position downstream of the external throttle 368b. Even when the forward movement is restricted due to the flange 16 coming into contact with an external member or reaching the forward limit position, the lock units 29 and 129 are released as long as compressed air is supplied to the forward fluid passage 367. State is maintained.

  Next, when the flow path switching valve 366 is switched to connect the compressed air source 365 to the retreating fluid flow path 368 and the forward fluid flow path 367 is opened to the atmosphere, the compressed air is supplied to the retreating pressure chamber 35. As a result, 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 from the forward pressure chamber 34 passes through the external throttle 367 b and is released into the atmosphere. At this time, the release fluid channel 370 is outside the forward fluid channel 367. Since the connection is made at a position upstream from the throttle 367b, 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 and 129 maintain the state in which the fastening is released.

  As shown in FIG. 9, when the backward movement of the flange 16, the piston rod 14 and the main piston 23 is restricted due to the cylinder stopper 307 coming into contact with the stage stopper 308 positioned on the backward side, for example, first, The back pressure in the unlocking pressure chamber 48 is discharged from the external throttle 367b through the unlocking fluid supply passage and the releasing fluid passage 370, and the pressure is reduced. Further, since the volume of the retreating pressure chamber 35 is fixed without the main piston 23 moving, the supplied compressed air is used as the lock fluid via the fixing fluid flow path 369 and the lock fluid supply path to each lock pressure. The lock units 29 and 129 are forcibly fastened by being introduced into the chamber 47.

  At this time, the lock fluid supply path first introduces compressed air into the lock pressure chamber 47 in the cylinder side lock piston accommodating portion 117 and then introduces compressed air into the lock pressure chamber 47 in the flange side lock piston accommodating portion 17. . Therefore, it is possible to provide a time difference in the operation of the two lock pistons 45 and 145, and thereby play can be removed sequentially from the two lock units 29 and 129, so that the moving position of the piston rod 14 can be fixed well. become able to.

  In particular, in the present embodiment, the cylinder side lock unit 129 is actuated first, and then the flange side lock unit 29 is actuated, so that the piston rod 14 and the flange 16 are moved backward as shown in FIG. In the utilization mode of the backward limit type in which the lock unit 29 and 129 are fixed in a restricted state, play in each lock unit 29 and 129 can be removed best, and secure fixing is possible. Further, the time difference of operation can be changed by changing the length of the fluid communication path 363 between the lock pressure chambers 47.

  Further, when supply of compressed air is stopped to both the forward fluid passage 367 and the backward fluid passage 368, and neither unlocking fluid nor back pressure is supplied to each unlocking pressure chamber 48. As in the first embodiment, the lock pistons 45 and 145 are pushed down to the operating position by the thrust of the lock spring member 46, the lock units 29 and 129 are brought into a fastening state, and the shaft of the piston rod 14 is The direction position will be fixed.

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

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, the fluid pressure cylinders 11, 211, 311 are used for fixing the panel material W constituting the automobile body to the handling device 4, but may be used for fixing other than the panel material. It can also be used for purposes other than fixing in 4.

  Furthermore, when the lock units 29 and 129 are operated, the steel ball 36 is pressed against the piston rod 14, but not only the steel ball 36 but also a ball using other materials may be used. Other members may be used instead of the balls. For example, a member in which a slit is formed in an annular member and the inner diameter is reduced by elastic deformation may be used.

  In addition, although air is used as the fluid when operating the fluid pressure cylinders 11, 211, 311, it goes without saying that other fluids may be used.

It is a figure which shows a part of vehicle body assembly line which conveyed the panel material which comprises a motor vehicle body with the robot arm provided with the handling apparatus. It is a figure which shows the fluid pressure cylinder of 1st Embodiment, Comprising: (A) is the left view, (B) is the top view, (C) is the right view. FIG. 3 is an axial sectional view of the fluid pressure cylinder taken along line XX corresponding to the axial center of the piston rod in FIG. 2. It is a figure which illustrates simply the fluid pressure circuit which a fluid pressure cylinder connects, and the path composition which supplies compressed air to each lock pressure room and each lock release pressure room. (A) is sectional drawing which shows a part of fluid pressure cylinder which the lock unit by the side of a flange will be in the cancellation | release state, (B) is a fluid pressure cylinder of the flange side lock unit which can be switched from a cancellation | release state to a fastening state It is sectional drawing which shows a part. (A) is sectional drawing which shows a part of fluid pressure cylinder by which the lock unit by the side of a flange is switched from a cancellation | release state to a fastening state, (B) of the fluid pressure cylinder by which the lock unit by the side of a flange became a fastening state It is sectional drawing which shows a part. It is an axial sectional view of a fluid pressure cylinder which is a modification of the first embodiment. It is an axial sectional view of a fluid pressure cylinder of a second embodiment. It is a figure which illustrates simply the fluid pressure circuit which a fluid pressure cylinder connects, and the path composition which supplies compressed air to each lock pressure room and each lock release pressure room.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Robot arm 2 Arm 3 Movable joint 4 Handling apparatus 6 Insertion clamp 7 Cylinder stopper 8 Stage stopper 11 Fluid pressure cylinder 12 Cylinder block 13 Lock guide block 14 Piston rod 15 Auxiliary rod 16 Flange 17, 117 Lock piston accommodating part 20 Forward feed Exhaust port 21 Retraction supply / exhaust port 22 Supply / exhaust passage 23 Main piston 23a First disc 23b Second disc 23d Rubber damper 24 Piston accommodation hole 25 Central rod cover 26 Plug 28 Cylinder chamber 29, 129 Lock unit 30 Lock unit accommodation hole 31 Tip Rod cover 33 Lock unit accommodating portion 34 Advance pressure chamber 35 Retreat pressure chamber 36 Steel ball (ball)
37 Cage 38 Lock sleeve 38a Inner taper surface 38b Outer taper surface (inclined surface)
39 Spring receiving member 40 Release spring member 41 Holding spring member 42 Positioning sleeve 43 Cylinder 44 Head cover 45, 145 Lock piston 45a Flange portion 45b Spring accommodating hole 45c Cylinder hole 45d Lock taper surface (pressing surface)
45e Taper rod part 46 Locking spring member 47 Locking pressure chamber 48 Unlocking pressure chamber 49 Spring receiving member 50 Plunger 50a Piston part 50b Rod part 50c Through hole 51 Plunger spring members 52, 152 Fluid introduction holes 53, 153 Fluid discharge hole 54 Valve seat 55 Communication path 56 U packing 57 Screw member 58 Communication gap 59 Internal check valve 60 Internal throttle 61 Fixed supply / exhaust port 62 Fluid introduction path 63 Fluid communication path 65 Compressed air source 66 Channel switching valve 66a Input port 66b , 66c Output port 67 Forward fluid channel 68 Reverse fluid channel 67a, 68a External check valves 67b, 68b External throttle 69 Fixed fluid channel 211 Fluid pressure cylinder 213 Lock guide block 233 Lock unit housing portion 307 Cylinder Stopper 308 Stage stopper 31 Fluid pressure cylinder 313 Lock guide block 325 Central rod cover 362 Fluid introduction path 363 Fluid communication path 364 Release supply / exhaust port 365 Compressed air source 366 Channel switching valve 366a Input port 366b, 366c Output port 367 Forward fluid channel 368 Backward Fluid flow path 367a, 368a External check valve 367b, 368b External throttle 369 Fixing fluid flow path 370 Release fluid flow path S1-Sn Work stage W Work piece C1-C4 Clearance

Claims (10)

A cylinder body that contains a main piston fixed to the piston rod in a reciprocating manner and is divided into a forward pressure chamber and a backward pressure chamber;
Two lock units assembled to the piston rod and provided with an inclined surface;
Two locks each having a pressing surface corresponding to the inclined surface and housed in the lock piston housing portion so as to be reciprocally movable between a forward limit position approaching the piston rod and a backward limit position away from the piston rod. A piston,
The inclined surface of one of the lock units is in contact with the side surface on the piston rod advance side of the pressing surface of one of the lock pistons, and the side surface on the piston rod retreating side of the pressing surface of the other lock piston. The fluid pressure cylinder, wherein the inclined surface of the other lock unit is in contact with the cylinder.   2. The fluid pressure cylinder according to claim 1, wherein the two lock units are installed such that the inclined surfaces thereof face each other in the axial direction.   3. The fluid pressure cylinder according to claim 1, wherein the two lock units operate in a fastening state in which the two lock units are fastened to the piston rod and a release state in which the fastening is released, respectively, and the two lock pistons are A hydraulic cylinder, wherein each of the hydraulic cylinders is an operating position for switching the lock unit to a fastening state at the forward limit position, and a retracted position for switching the lock unit to a release state at the backward limit position.   4. The fluid pressure cylinder according to claim 1, wherein each of the two lock pistons divides the inside of the lock piston housing into a lock pressure chamber and a lock release pressure chamber, and each of the lock cylinders. A lock fluid supply path that guides a lock fluid that communicates with a pressure chamber and applies a thrust to the lock unit via the lock piston, and a lock fluid supply path that communicates with each lock release pressure chamber via the lock piston. An unlocking fluid supply path for guiding the unlocking fluid for releasing the thrust from, and a lock spring member that is incorporated in each of the lock pressure chambers and applies a thrust of the spring to the lock unit via the lock piston. And the thrust of the lock fluid and the thrust of the lock spring member are forwarded via the lock unit. Fluid pressure cylinder, characterized in that added to the axial direction of the piston rod.   5. The fluid pressure cylinder according to claim 4, wherein the lock fluid supply path guides the lock fluid in order by connecting the two lock pressure chambers in series.   6. The fluid pressure cylinder according to claim 4, wherein the unlocking fluid supply path supplies and discharges fluid to and from the outside, and the retreat pressure chamber is provided with an internal check valve disposed in parallel. The internal check valve is connected to the unlocking fluid supply passage through a throttle, and the internal check valve closes in the reverse direction by allowing fluid to pass in the direction of guiding from the reverse pressure chamber to the unlocking fluid supply passage. A fluid pressure cylinder characterized by being installed in an arrangement.   6. The fluid pressure cylinder according to claim 4, wherein the unlocking fluid supply path communicates with the forward pressure chamber, and the lock fluid supply path communicates with the reverse pressure chamber. Pressure cylinder.   The fluid pressure cylinder according to any one of claims 4 to 7, wherein the cylinder is slidably mounted on the lock piston, and the lock fluid is supplied after the lock piston moves toward the operating position with a predetermined stroke. A fluid pressure cylinder having a plunger that opens a passage to the lock pressure chamber, and applying a thrust of the lock fluid after applying a thrust of the lock spring member to the lock piston.   The fluid pressure cylinder according to any one of claims 4 to 8, wherein each of the two lock pistons reciprocates in a radial direction of the piston rod, and the pressure surface is formed via the pressing surface formed on the lock piston. A fluid pressure cylinder, wherein thrust is transmitted to the inclined surface of the lock unit. The fluid pressure cylinder according to any one of claims 1 to 9, wherein the two lock units are each mounted with a ball disposed on an outer peripheral surface of the piston rod and reciprocally movable in an axial direction of the piston rod. And a lock sleeve fastened to the piston rod via the ball.

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