JPH0711858Y2 - Hydraulic actuator - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial field of application) The present invention uses a hydraulic pressure to move a piston to operate a machining tool such as a cutter or punch attached to the tip of the piston. The present invention relates to a hydraulic actuator.

(Prior Art) An oil tank that stores hydraulic oil inside, a hydraulic pump that is operated by a drive source such as an electric motor, and pumps this hydraulic oil to the cylinder chamber, and a reciprocatingly arranged inside the cylinder chamber. ,
There is known a portable hydraulic actuator that includes a piston rod having a rod protruding outside the cylinder chamber and a machining tool such as a cutter or a punch attached to the tip of the piston rod (for example, actual opening). 51-29192).

In such a hydraulic actuating device, in order to smoothly reciprocate the piston in the cylinder chamber, the pressure buffer is connected to the cylinder chamber at the piston front side (the side where the piston is pushed by the hydraulic fluid to advance). A chamber is provided, and a flexible air bag is inserted and arranged in the pressure buffer chamber.
One end of the air bag is open and communicates with the atmosphere, and the volume of the air bag can be contracted and expanded by a change in pressure acting on the pressure buffer chamber.

Since the air bag may move in the pressure buffer chamber when it is contracted and inflated, its open end needs to be firmly fastened in the pressure buffer chamber.

In the conventional device, in order to prevent the air bladder from jumping out of the pressure buffer chamber, as shown in Japanese Utility Model Laid-Open No. 51-29192, the diameter of the opening of the pressure buffer chamber on the side communicating with the atmosphere is reduced. , A step is provided. For this reason, the insertion and removal of the air bag cannot be performed from the outside due to the hindrance of the step, and the hydraulic actuator itself must be disassembled.

Since disassembling the hydraulic actuating device causes various problems and is a troublesome work, a method has been proposed in which the air bag can be replaced without disassembling the hydraulic working device (Japanese Utility Model Laid-Open No. 63-127823). ).

(Problems to be solved by the invention) In the hydraulic actuator disclosed in Japanese Utility Model Laid-Open No. 63-127823, a step portion is provided at the opening to the atmosphere of the pressure buffer chamber into which the air bag is inserted. Instead, the air bag can be directly inserted from the outside into the pressure buffer chamber.

However, in this hydraulic operating device, since no step is provided at the opening of the pressure buffer chamber to the atmosphere, a locking groove is provided on the outer periphery of the air bag mounting member to prevent the air bag from coming off. The tip of the set screw that is screwed into the tap hole of the casing body must be locked in this locking groove.

When the tap hole is formed in the casing body and the set screw is screwed into the casing body in this way, when the casing body has a large thickness, the machining is troublesome and a long set screw is required, and the assembling work is also time-consuming. Takes. In addition, it is necessary to align the air bag in the axial direction, and the air bag may move even after the attachment in accordance with the width of the locking groove. Further, since it is difficult to use a plurality of setscrews, the air bag mounting member is not sufficiently fixed, and repeated movement of the air bag mounting member causes a gap with the opening of the pressure buffer chamber. The hydraulic oil may leak.

The present invention has been made in consideration of the above points, and provides a hydraulic operating device that allows the air bag to be inserted into and removed from the pressure buffer chamber from the outside and allows the air bag to be firmly attached without oil leakage. The purpose is to provide.

[Constitution of device]

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a pressure buffer chamber in an air bag storage chamber in which an air bag is inserted, and an inlet side opening of the storage chamber. Female threaded portion and a concave portion having a diameter larger than that of the female threaded portion provided at the inlet side opening of the female threaded portion, and a male threaded portion screwed to the female threaded portion is provided at one end, and the other. The air bag is mounted by attaching an opening of the air bag to one end of a hollow holder having a flange portion at the end and a through hole formed in the central portion.

(Operation) According to the present invention, the air bag can be easily attached and detached by simply rotating the hollow holder from the outside of the casing.

According to the present invention, the attachment / detachment work can always be performed from a fixed direction, and the air bag can be positioned and fixed securely, which is excellent in workability and can prevent oil leakage.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 10 is a main body casing of the hydraulic operating device, and an oil tank 1 in which operating oil is stored in the casing 10.
1, a cylinder chamber 12 is formed. An oil pressure generating pump 14 driven by an electric motor 13 is disposed in the oil tank 11, and the hydraulic oil is sent to the cylinder chamber 12 through an oil passage 15 by the pressure generated by the pump 14. There is. A piston 16 is arranged in the cylinder chamber 12 so as to be able to reciprocate, and a rod 17 protrudes outward from the cylinder chamber 12 on the front side of the piston 16 (the side that is pushed by the hydraulic oil to advance). Are connected together. A working tool, for example, a punch 18 is attached to the tip of the rod 17 so that the punching can be performed in cooperation with a die 19 fixed to the casing 10 at an opposite position.

A pressure buffer chamber is provided in the casing 10 so as to communicate with the cylinder chamber 12 at the front side of the piston 16. The pressure buffer chamber includes an air bag storage chamber 22 into which the air bag 21 is inserted and arranged.
The air bag storage chamber 22 communicates with the cylinder chamber 12 at the front side position of the piston 16 by the oil passage 22a.

A female screw portion 23 provided adjacent to the inlet side opening portion of the air bag storage chamber 22 is provided, and further opened to the outside of the casing at a position adjacent to the inlet side opening portion of the female screw portion 23. Then, a recess 24 having a diameter larger than that of the female screw portion 23 is provided so as to form a step.

In the figure, reference numeral 25 is a hollow holder having a through hole 25a formed in the center. The hollow holder 25 is provided with a male screw portion 25b that is screwed into the female screw portion 23 at the outer periphery of the tip, and a flange portion 25c that is larger than the diameter of the female screw portion 23 and smaller than the diameter of the recess 24 is formed at the rear end. There is. The hollow holder 25 is provided on the rear side of the flange portion 25c (the side facing the outside of the casing 10).
A locking hole 25d for rotating the is formed.

A hollow bush 26 is fitted in the through hole 25a of the hollow holder 25. The hollow bush 26 has a female screw portion 26a formed through the center thereof, and a flange-shaped connecting portion 26b at one end to which the opening portion of the air bag 21 is connected.

A bolt 27 is screwed into the female screw portion 26a of the hollow bush 26. This bolt 27 has a through hole for ventilation in the axial direction.
27a is provided, and the bolt head 27b is in contact with the flange portion 25c of the hollow holder 25 via a washer 28 having a larger diameter than the through hole 25a of the hollow holder 25.

The air bag 21 is made of a flexible material such as oil resistant rubber and has one end open. The opening is sandwiched between the connecting portion 26b of the hollow bush 26 and the end of the hollow holder 25 and held by the hollow holder 25.

Reference numeral 28 is an O-ring for the oil seal, and the flange portion
It is arranged between 25c and the entrance opening of the female screw portion 23.

Next, the operation of this embodiment having such a configuration will be described.

When the air bag 21 is taken out from the casing 10, a claw (not shown) of a rotating tool is inserted and engaged in the locking hole 25d of the hollow holder 25, and the hollow holder 25 is rotated. When the male screw portion 25b of the hollow holder 25 and the female screw portion 23 are unscrewed and the hollow holder 25 is pulled out from the recess 24, the air bag 21 is also pulled out from the pressure buffer chamber 22.

To replace the air bladder 21, turn the bolt 27 to rotate the hollow bush 26.
This is performed by separating the connecting portion 26b of the above from the hollow holder 25.

The opening end of the new air bag 21 is sandwiched between the end of the hollow holder 25 and the connecting portion 26b of the hollow bush 26, and the bolt 27 is rotated and tightened in the female screw portion 26a. Then, the air bag 21 is inserted into the pressure buffer chamber 22, and the male screw portion 25b of the hollow holder 25 is screwed into the female screw portion 23. By bringing the flange portion 25c into contact with the step between the recess 24 and the female screw portion 23, the air bag
Finish wearing 21.

The inside of the air bag 21 is a through hole for ventilation provided in the bolt 27.
The air bag 21 is communicated with the atmosphere by 27a, the air bag 21 is contracted and expanded in response to the change in the pressure of the cylinder chamber 12, the pressure is buffered, and the piston 16 can be smoothly moved.

As described above, according to the present embodiment, the female holder 23 is formed in the inlet side opening of the pressure buffer chamber 22 and the recess 24 having a larger diameter is formed to form a step, and the hollow holder having the flange 25c is provided. Since the air bag 21 is screwed and fixed at 25, the work for attaching and detaching the air bag 21 can be always performed in only one direction, and the air bag 21 can be securely fixed. Further, a bolt 27 is screwed into a hollow bush 26 having a female screw portion 26a, and the bolt 27 is turned to rotate the bolt 27.
Since the opening end of the air bag 21 can be sandwiched between the hollow holder 25 and the end of the hollow holder 25, the tightening force of the bolt 27 can be sufficiently transmitted compared to the case where a simple disk-shaped nut is used. 21 can be fixed securely.

[Effect of device]

As described above, according to the present invention, since the set screw or the like is not used unlike the conventional device, the air bag attaching device can be configured regardless of the thickness of the casing.
The hollow holder can not only be easily operated from the outside of the casing, but also by using this, the holder can be firmly fixed and positioned reliably. In addition, this also provides an excellent effect such that oil leakage from the pressure buffer chamber can be reliably prevented. Furthermore, inside the through hole of the hollow holder, a female screw portion is formed penetrating through the center, and a flange-shaped connecting portion to which the opening portion of the air bag is connected is formed at one end so that the hollow bush can slide. Further, the female thread portion of this hollow bush is provided with a through hole for ventilation in the axial direction, and a screw member having a flange portion having a diameter larger than that of the through hole of the hollow holder is screwed into the female thread portion of the air bag. The opening end can be firmly clamped by holding the flange-shaped connecting portion of the hollow bush and the end of the hollow holder and rotating the screw member. This further secures the fixing of the air bladder, and it is possible to reliably prevent an accident in which the fixed state of the air bladder is loosened during use of the hydraulic actuator and oil leakage occurs.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a hydraulic operating device according to the present invention. 10 ... Casing, 11 ... Oil tank, 12 ... Cylinder chamber, 16 ... Piston, 17 ... Rod, 21 ... Air bag, 22 ... Air bag storage chamber, 22
a ... Oil passage, 23 ... Female screw part, 24 ... Recessed part, 25 ... Hollow holder, 25a ... Through hole, 25b ... Male screw part, 25c ... Flange part, 26 ... Hollow bush, 27 ... Bolt.

Claims (1)

[Scope of utility model registration request] 1. A casing in which a cylinder chamber is formed, a piston which is disposed in the cylinder chamber and reciprocates by pressure oil supplied to the cylinder chamber, and a cylinder chamber at a position on the front side of the piston communicates with the inside of the casing. A pressure actuating chamber provided in the pressure buffer chamber, and a flexible air bag inserted into the pressure buffer chamber and having one end opened and the opening communicating with the atmosphere. In the chamber, an air bag storage chamber in which an air bag is inserted and arranged, a female screw portion provided adjacent to the inlet side opening of the storage chamber, and a position adjacent to the inlet side opening of the female screw portion. And a recess having a larger diameter than the female screw portion is provided outside the casing, and the female screw portion has a male screw portion at one end and a larger diameter than the female screw portion at the other end, and Diameter smaller than the recess A hollow holder having a flange portion and a through hole formed in the center is attached by screwing the male screw portion, the through hole of the hollow holder is formed with a female screw portion penetrating in the center, A hollow bush, in which a flange-shaped connecting portion to which the opening of the air bag is connected is formed, is slidably inserted at one end, and the female screw portion of the hollow bush has an axial through hole for ventilation. And a screw member having a flange portion having a diameter larger than that of the through hole of the hollow holder is screwed together.