JP4947461B2 - Boost type fluid pressure cylinder - Google Patents

Description

  The present invention relates to a fluid pressure cylinder such as an air cylinder or a hydraulic cylinder, and more particularly to a boosted fluid pressure cylinder that increases an operating force in a specific region of a cylinder stroke.

  The fluid pressure cylinder is used in various operating mechanisms such as a caulking mechanism, a clamp mechanism, and a compression mechanism. In such a caulking mechanism, the operating force is usually not required at the start of the cylinder operation. It is necessary to output a larger operating force when operating to the part.

For this reason, when deciding the size of the fluid pressure cylinder to be used in the caulking mechanism, etc., a fluid pressure cylinder of a size (large diameter of the cylinder tube) that can obtain the maximum required operating force has been selected in the past. However, in order to improve this, as described in JP-A-5-164111, JP-A-6-42507, and JP-A-6-300008, the piston rod of the cylinder and the boosting piston of the auxiliary cylinder are used. Was locked near the end of the stroke, and the operating force for the booster piston could be increased to reduce the installation space.
JP-A-5-164111 JP-A-6-42507 JP-A-6-300008

  However, in the conventional pressure increasing type fluid pressure cylinder, an auxiliary cylinder portion having a pressure increasing piston in the cylinder chamber is coaxially attached to the outside of the lot cover on the piston rod exit side of the fluid pressure cylinder, and the tapered surface inside the pressure increasing piston is provided. Since the piston rod outer peripheral surface of the fluid pressure cylinder was locked by the locking steel ball, the piston rod outer peripheral surface was damaged by the hard steel ball due to repeated operation of the pressure-increasing cylinder, and the seal packing of the piston rod sliding part was removed. There was a problem in that it was damaged and could not be sealed, causing leakage or malfunction due to seal leakage.

  For this purpose, the intensifying fluid pressure cylinder according to claim 1 of the present invention is provided with an auxiliary cylinder in series for increasing the force outside the head cover of the fluid pressure cylinder, and the piston and piston rod of the fluid pressure cylinder are integrally fixed. A space with a tapered surface is formed inside the piston, and a clutch shaft connected to a boosting piston rod in the auxiliary cylinder attached to the outside of the head cover can be inserted in the space, and the piston can be inserted. A rolling lock body is disposed between the inner tapered surface and the outer peripheral surface of the clutch shaft inserted into the inner space of the tapered surface.

  In this intensifying fluid pressure cylinder, fluid pressure is pressurized in the cylinder chamber between the head cover and the piston, and the piston and the piston rod are driven in the pushing direction. At this time, when the piston moves to a position where it wants to be boosted, pressurizing the fluid pressure in the booster cylinder chamber between the auxiliary head cover of the auxiliary cylinder and the booster piston, and pushing the booster piston, the rolling lock body is moved by the tapered surface inside the piston. The piston and clutch shaft are locked by being strongly pressed by the outer peripheral surface of the clutch shaft connected to the boosting piston rod. For this reason, after locking, the operating force of the piston and the operating force of the boosting piston are applied and increased, and the piston rod is pushed out.

  In the intensification type fluid pressure cylinder according to claim 2, the lock is provided with a lock releasing portion protruding so as to release the lock by pushing back the rolling lock body by pressurizing the fluid pressure in the cylinder chamber between the rod cover and the piston. The release piston is slidably disposed inside the piston.

  In the intensifying type hydraulic cylinder of claim 3, the rolling lock body is a roller pin, so that the contact surface is widened, and when the piston and the clutch shaft having a large operating force are locked, the lock surface may be damaged. Without deformation, the operating force of the fluid pressure cylinder is increased and the piston rod is pushed out.

  In these intensification type fluid pressure cylinders according to claims 1 and 3, the rolling lock body strongly presses and locks the outer peripheral surface of the clutch shaft connected to the intensification piston rod by the taper surface inside the piston of the fluid pressure cylinder. Therefore, there is no need to seal the fluid pressure on each lock surface, and there is no need to finish the lock surface with high precision as in the past, and malfunctions caused by foreign matter, scratches or deformation of the lock surface. Therefore, it is possible to provide a boosted fluid pressure cylinder that is inexpensive and has a long service life. In particular, in the intensifying fluid pressure cylinder of claim 3, since it is not necessary to seal the outer peripheral surface of the clutch shaft, the lock body is a roller pin, and the taper surface inside the piston, which becomes the lock surface, and the clutch shaft outer peripheral surface are flat. Therefore, the lock contact surface is widened, and the lock connection with the high-power auxiliary cylinder can be handled without causing damage or deformation to the lock surface.

  According to the intensifying fluid pressure cylinder of claim 2, after the pushing operation of the intensifying fluid pressure cylinder is completed, when the piston rod is retracted, that is, the fluid pressure is applied from the rod cover side of the fluid pressure cylinder. When the pressure is applied, the unlocking piston slides inside the piston toward the head cover, and the unlocking part protruding from the unlocking piston rolls back to lock the lock body, so the piston and clutch shaft are securely unlocked. Yes, the piston rod can be pulled in smoothly.

    Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a plan view of an intensifying fluid pressure cylinder, and FIG. 4 shows an ii enlarged sectional view thereof. The rod cover 3 slidably supports the piston rod 20 at the end of the cylinder tube 8 on the piston rod 20 side, and is fixed so as to close the cylinder tube opening. The head cover is attached to the end of the cylinder tube 8 at the piston 10 side. 4 is fixed so as to slidably support a boosting piston rod 9 fixed to the boosting piston 6 of the auxiliary cylinder 2.

  In the auxiliary cylinder 2, the end of the auxiliary cylinder tube 8a on the side of the boosting piston rod 9 is fixed to the head cover 4, the end of the boosting piston 6 on the side of the auxiliary head cover 5 is closed, and the end of the auxiliary cylinder tube 8a has a boosting piston. 6 is inserted and the boosting piston rod 9 fixed to the boosting piston 6 is supported by the bearing metal 44 in the central inner diameter portion of the head cover 4 and is inserted into the fluid pressure cylinder 1 side. The clutch shaft 7 is connected and extends in the space inside the piston 10 and the piston rod 20 of the fluid pressure cylinder.

  A piston 10 is slidably inserted into the cylinder tube 8 of the fluid pressure cylinder 1, a hole 12 is provided in the central axis direction of the piston 10, and a clutch shaft 7 protruding from the auxiliary cylinder 2 is inserted therethrough. A concave groove is disposed in the central hole portion 10 toward the outer diameter side, and a space (substantially conical concave portion) 19 having a tapered surface (conical inclined surface) 19a is formed on the outer diameter side of the concave groove. The The space 19 is positioned so as to surround the periphery of the clutch shaft 7, and the tapered surface 19 a is formed to have a smaller diameter toward the tip side of the clutch shaft 7.

  Further, in the space 19, for example, as shown in FIG. 2, eight locking steel balls 18 as rolling lock bodies are disposed so as to surround the periphery of the clutch shaft 7. The steel ball 18 for locking has an outer diameter that can contact the tapered surface 19a and the outer peripheral surface of the clutch shaft 7 near the center of the taper. A seal member 13 is fitted on the outer periphery of the piston 10.

  The rod cover 3 of the fluid pressure cylinder 1 is provided with an air supply / exhaust port 31 and further communicates with the fluid pressure cylinder chamber 21 through a passage 31a, and the head cover 4 is provided with an air supply / exhaust port 41 and an air hole 42, respectively. , 42a communicates with the fluid pressure cylinder chamber 21 and the auxiliary cylinder chamber 22, and the auxiliary head cover 5 is provided with a supply / exhaust port 51, and communicates with the auxiliary cylinder chamber 22 through a passage 51a. Further, a return spring 23 is disposed between the head cover 4 and the boosting piston 6 to push back the boosting piston 6 toward the auxiliary head cover 5 when no fluid pressure is applied from the air supply / exhaust port 51 provided in the auxiliary head cover 5. Is done.

  In operation, as shown in FIG. 4, the fluid pressure cylinder switching direction switching valve (not shown) is operated with the boosting piston 6 positioned on the end face of the auxiliary head cover 5 and the piston rod 20 in the retracted position. When the fluid pressure is switched to pressurize the supply / exhaust port 41, the piston 10 receives an operating force in the direction of the rod cover 3, and the piston rod 20 advances in the pushing direction. At this time, since the fluid pressure is not applied to the supply / exhaust port 51 of the auxiliary head cover 5 of the auxiliary cylinder 2, the piston rod 20 advances in the pushing direction by the operating force of the piston 10.

  When the piston rod 20 advances in the pushing direction and moves to the position P that requires the increased operating force shown in FIG. 5, when the fluid pressure is increased to the supply / exhaust port 51 of the auxiliary head cover 5, Is pressurized to the booster cylinder chamber 22 through the passage 51a, and the booster piston 6 overcomes the return spring 23 and moves in the direction of the head cover 4. Therefore, the clutch shaft 7 connected to the booster piston rod also moves in the hole 12 in the same direction. The locking steel ball 18 in the inner groove on the inner diameter side of the piston 10 is strongly pressed against the outer peripheral surface of the clutch shaft 7 by the tapered surface 19a of the groove. For this reason, the clutch shaft 7 is locked to the piston 10 by the locking steel ball 18. Therefore, the piston rod 20 that has reached the boosting position in FIG. 5 is pushed out by the operating force obtained by adding the operating force of the boosting piston 6 to the operating force of the piston 10.

  Next, when the piston rod 20 is retracted, as shown in FIG. 6, when the fluid pressure is exhausted from the air supply / exhaust port 51 of the auxiliary head cover 5, the boosting piston 6 is moved toward the auxiliary head cover 5 by the return spring 23 to lock. Since the clutch shaft 7 locked with the piston 10 by the steel ball 18 also moves in the same direction, the force to return the locking steel ball 18 that has locked the piston 10 and the clutch shaft 7 to the large diameter side of the concave groove taper surface. Working and unlocked. Further, when the fluid pressure cylinder switching direction switching valve pressurizes the fluid pressure from the supply / exhaust port 31 of the rod cover 3 of the fluid pressure cylinder 1 and exhausts the fluid pressure from the supply / exhaust port 41 of the rod cover 4, the unlocked piston The rod 20 moves in the direction of the head cover 4 by the return operating force of the piston 10.

  Further, in the intensifying fluid pressure cylinder according to the second aspect, when the fluid pressure is increased from the air supply / exhaust port 31 of the rod cover 3 when the piston rod 20 is retracted, the fluid pressure passes through the passage 31a and the rod cover 3 and the piston. The cylinder chamber 21 between 10 is pressurized and passes through a passage 10b provided in the vicinity of the outer diameter of the piston rod 20 in the central axis direction of the piston 10 to be slidably disposed inside the piston 10 The piston 15 is pressurized, and the unlocking piston 15 moves in the direction of the locking steel ball 18. As shown in FIG. 6, the locking steel ball 18 is moved to the piston inner groove groove taper by the protrusion 15 a of the unlocking piston 15. Pushing to the large diameter side of the surface, the lock is reliably released.

  Next, another embodiment shown in claim 3 will be described. As shown in FIG. 3, a hole 12 is arranged in the direction of the central axis of the piston 10a as in the first embodiment. A concave groove is disposed toward the outer diameter side of the piston 10a at the piston central portion of the hole, and a space 19 having a multifaceted tapered surface (hexagonal cone inclined surface) 19b is formed on the outer diameter side of the concave groove. The space is located so as to surround the periphery of the crankshaft 71 having a hexagonal cross section, and the tapered surface 19b is formed on the front end side of the clutch shaft 7 so as to have a small diameter.

  In the space 19, six roller pins 18 a serving as rolling lock bodies are disposed so as to surround the crankshaft 71. The roller pin 18a has an outer diameter capable of contacting the tapered surface 19b and the hexagonal plane of the crankshaft 71 near the center of the taper.

  In this case, the operation is the same as that of the first embodiment, but the locking surface is widened by flattening the locking contact surface between the inner tapered surface 19b of the piston 10a and the roller pin 18a on the outer peripheral surface of the clutch shaft 71. Therefore, even in the lock coupling with the auxiliary cylinder which has been greatly increased in force, it can be dealt with without any damage or deformation.

  As an embodiment of the present invention, the piston 10 of the fluid pressure cylinder 1 has an outer diameter of φ90 mm, and the design of the lock coupling portion according to claim 1 is that the inner concave groove taper portion 19a of the piston 10 has a small diameter side of φ57 mm, The large-diameter side has a conical shape with a taper angle of 9.5 degrees and a lock steel ball 18 of 12 mm, and the outer diameter of the lock shaft 7 is 36 mm. The design of the lock coupling portion according to claim 3 is that the inner concave groove multi-sided taper surface (hexagonal cone inclined surface) 19b of the piston 10a has a taper angle of 9.5 with a small-diameter side hexagonal width of 57 mm and a large-diameter side hexagonal width of 63 mm. The lock roller pin 18a has a roller pin diameter of 12 mm and a length of 18 mm, and the lock shaft 71 has a hexagonal facing size of 36 mm. The lock coupling contact surface sufficiently quenches the carbon steel, and considering the wear resistance and scratch resistance, a stable operation can be obtained even after 5 million repetitive operations.

  The auxiliary cylinder 2 can be doubled by a lock connection with the auxiliary cylinder 2 having the boosting piston 6 having the same diameter as the piston outer diameter φ90 mm of the fluid pressure cylinder 1. Further, in the case of claim 3, an increase in power 8 times that of the fluid pressure cylinder can be realized by locking and connecting an intensification cylinder as an auxiliary cylinder by JP-A-2005-164019. As described above, as the auxiliary cylinder, a pneumatic cylinder, a hydraulic cylinder, a booster cylinder, and the like can be appropriately selected as necessary.

It is a top view of an intensification type fluid pressure cylinder which shows one example of the present invention. FIG. 5 is a reduced sectional view taken along line ii-ii in FIG. 4. It is ii-ii reduced sectional drawing of FIG. 4 which shows another Example. It is the ii expanded sectional view of FIG. (The drawing is rotated 90 ° clockwise due to space) It is the ii expanded sectional view of FIG. 1 in a lock coupling position. (The drawing is rotated 90 ° clockwise due to space) FIG. 2 is an enlarged cross-sectional view taken along line ii of FIG. 1 in an unlocked state. (The drawing is rotated 90 ° clockwise due to space)

Explanation of symbols

1-Fluid pressure cylinder 2-Auxiliary cylinder 3-Rod cover 4-Head cover 5-Auxiliary head cover 6-Boosting piston 7, 71-Clutch shaft 8-Cylinder tube 8a-Auxiliary cylinder tube 9-Boosting piston rod 10, 10a-Piston 10b , 31a, 41a, 42a, 51a-passage 12-holes 13, 15b, 32, 61-seal member 15-unlocking piston 15a-protrusion 18-locking steel ball 18a-roller pin 19-space 19a, 19b-taper Surface 20-Piston rod 21-Fluid pressure cylinder chamber 22-Boosting cylinder chamber 23-Return spring 31, 41, 51-Supply / exhaust port 33, 44-Bearing metal 42-Air hole

Claims (2)

An auxiliary cylinder is attached in series outside the head cover of the fluid pressure cylinder. A piston and a piston rod are integrally fixed in the cylinder chamber of the fluid pressure cylinder, and a space having a tapered surface is formed inside the piston. A clutch shaft connected to the pressure-increasing piston rod of the auxiliary cylinder can be inserted in the inside, and a rolling lock for locking and coupling the inner tapered surface and the outer peripheral surface of the clutch shaft to the inner diameter portion of the piston. A lock release piston that is slidable in the direction of movement of the body and the piston is disposed, and an unlocking portion that pushes back the rolling lock body and releases the lock is projected on one end surface of the piston for unlocking , A booster type fluid pressure cylinder characterized in that a cylindrical portion for sealing a pressurized fluid on the outer peripheral surface projects from the other end surface .   2. The intensifying fluid pressure cylinder according to claim 1, wherein a lock coupling surface of the outer peripheral surface of the clutch shaft and an inner tapered surface of the piston is a flat surface, and a rolling lock body is a roller pin.

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