RU2201349C2 - Press hydraulic control system - Google Patents

Abstract

FIELD: mechanical engineering; units for control of hydraulic presses. SUBSTANCE: proposed hydraulic control system includes power supply source communicated with actuating hydraulic cylinders through hydraulic distributors. Control pump is connected with end cavities of hydraulic distributors of actuating hydraulic cylinders. Programmer mounted on rod of drive is used for change- over of control hydraulic distributors. Working fluid reservoir is made in form of housing with piston which forms rod and piston chambers. Piston of drive of working fluid reservoir is made in form of hydraulic cylinder with four-way two-position distributor connected with control pump and working fluid reservoir by means of pipe lines. Mounted on end face of rod of hydraulic cylinder of working fluid reservoir is valve mounted in spaced relation in piston between seat and stop for drainage of leakage from rod chamber to piston chamber. EFFECT: enhanced reliability. 2 dwg

Description

 The invention relates to mechanical engineering, and in particular to control devices for hydraulic vulcanizing presses and other hydraulic equipment.

 A control device for the actuating hydraulic cylinders of machines and automatic lines (Aut. St. 1132078. A control device for the actuating hydraulic cylinders of machines and automatic lines. Yu.A. Chernikov. Publ. BI 48, 1984), containing actuating hydraulic cylinders, a pump communicated through actuators with actuating valves hydraulic cylinders, a drive of program carriers associated with the cavities of the hydraulic cylinders, and a hydraulic compensator with a spring-loaded piston installed in the housing with the formation of two cavities - spring and working, reportedly th with a suction line, a piston drive of the hydraulic compensator in the form of a screw, a filter breather and a locking device connected to the drainage leakage collection line, a check valve installed between the spring and working cavities of the hydraulic compensator.

The presence of a spring in the hydraulic compensator with great effort and a drive in the form of a screw does not allow creating a compact control device and requires a lot of time when filling the hydraulic compensator with liquid and draining the collected leaks from its spring into the working cavity
Known hydraulic control system of the press (Aut. St. USSR 579176. Hydraulic control system of the press. Yu. A. Chernikov. Publ. BI 41, 1977), containing a power source that communicates via control valves with actuating hydraulic cylinders, a control pump connected to the end cavities hydraulic distributors of executive hydraulic cylinders through control valves, a drive connected to the hydraulic distributors of executive hydraulic cylinders, the rod of which contains a software device for switching hydraulic control valves, and hydraulic capacity for the working fluid.

 The working fluid of the known press control system (prototype) has contact with air, which reduces its service life and system. The presence of air reduces the speed and sensitivity of the system, leads to power losses, requires an increase in the volume of the working fluid of the system, contributes to increased foaming in the hydraulic capacity and the occurrence of cavitation. Saturation of the working fluid with air leads to its enhanced heating due to heat generation during compression of the air.

 The technical task is to increase reliability, improve maintenance and save working fluid.

 The specified technical problem is achieved by the fact that in the hydraulic control system of the press containing the power source, communicating through the control valves with the executive hydraulic cylinders, the control pump connected to the end cavities of the hydraulic control valves of the executive hydraulic cylinders through the control valves connected to the hydraulic control valves of the executive hydraulic cylinders, the actuator is located on its stock device for switching control valves, hydraulic capacity for ra the barrel fluid is made in the form of a housing with a piston installed in it with the formation of two cavities, and is equipped with a hydraulic piston drive, a breather filter and a locking device connected to a hydraulic line for collecting leaks and hydraulic capacity, while the hydraulic piston drive is made in the form of a four-way hydraulic cylinder a two-position distributor connected by pipelines to the control pump and hydraulic reservoir with rod and piston cavities, and a valve is mounted at the end of the hydraulic cylinder cylinder stem, which has a clearance An ohm is installed in the piston between the seat and the stop to drain the collected drainage leaks from the rod cavity of the hydraulic reservoir into the piston.

 Figure 1 shows a schematic hydraulic diagram of the press; figure 2 - device control valve and control valve of the hydraulic actuator.

 The system contains a power source 1, connected through the control valves 2 and 3 to the actuating cylinders 4 and 5, a control pump 6 connected to the end cavities of the control valves 2 and 3 of the actuating hydraulic cylinders 4 and 5 through the control valves 7, 8, 9 and 10, connected to the control valves actuator actuators 11, on the rod of which is located a software device 12 for switching control valves 7-10.

 The hydraulic system is equipped with a hydraulic reservoir 13, made in the form of a housing 14 with a piston 15 installed in it with the formation of two cavities 16 and 17, an actuator 18 of the hydraulic reservoir 15, made in the form of a hydraulic cylinder with a four-way two-position distributor 19, connected by pipelines 20 and 21 to the control pump 6 and a hydraulic reservoir 13, a filter-breather 22 and a locking device 23 connected to a hydraulic line 24 for collecting fluid leaks and a hydraulic tank (hydraulic lines for collecting drainage leaks are not shown in FIG. 1).

 At the end of the rod 25 of the hydraulic cylinder, a valve 26 is mounted, which is installed with a gap in the piston 15 between the seat 27 and the stop 28. The safety valves 29 and 30 limit the increase in pressure in the system over a predetermined one. The actuator 11 has a control valve 31, a rod 32 and cavities 33 and 34. The control valves 2 and 3 are connected by a pipe 35 to the control valve 31 of the drive 11.

 The control valve includes a spool 37 mounted in the housing 36 with a control button 38, springs 39 and 40 and a slider 41. The stiffness of the spring 39 is greater than the spring 40. The actuator hydraulic valve consists of a housing 42, a valve 43, a spring 44 and a washer 45.

 The press control system operates as follows. In the initial position, the software device 12, the rod 32 with the piston of the actuator 11 are in the extreme position.

 When you turn on the control pump 6 and the power source 1, the fluid enters through the valve 2 into the piston cavity of the actuator cylinder 4. From the rod cavity of the actuator cylinder 4, the fluid is forced out through the valve 2, pipe 35 and the valve 31 into the cavity 34 of the actuator 11. The rod 32 and the software device 12 move up and switch control valves 9 and 10. The fluid from the control pump 6 flows through the control valves 9 and 10 into the end cavities of the control valve 2, per Keys him. Now the fluid from the power source 1 enters through the valve 2 into the rod cavity of the actuating cylinder 4. From the piston cavity, the liquid through the valve 2, pipe 35 and valve 31 enters the cavity 34 of the actuator 11. The rod 32 and the software device move up and switch valves 7 and 9 . The control valve 2 is set in the middle position, and the control valve 3 is switched. The fluid from the power source 1 through the valve 3 enters the piston cavity of the hydraulic cylinder 5. From the rod cavity, the liquid through the valve 3, the pipe 35 and the valve 31 is displaced into the cavity 34 of the actuator 11. Next, the operation of the actuating hydraulic cylinder 5 is carried out in the same manner as the cylinder 4.

 In the highest position, the valve 31 switches and the rod 32 with the software device 12 returns down. In the extreme lower position, the valve 31 switches and the rod 32 with the software device 12 moves up and so on.

 The safety valve 30 maintains a predetermined pressure in the pipe 20, and the stem 25 presses the valve 26 against the seat 27. If necessary, drain collected leaks from the cavity 16 into the cavity 17 of the hydraulic reservoir 13, the power source 1 is turned off, the shut-off device 23 is closed and the four-way two-way valve 19 is switched. 25 with the valve 26 are moved by the amount of clearance between the valve 26 and the stop 28. Next, the valve 26 through the stop 28 moves the piston 15 up, the fluid from the cavity 16 flows into the cavity 17. Then the shut-off device opens roystvo switches 23 and control valve 19. Fluid from the pump control cylinder 6 via the piston accumulator tank 13, the rod 25 pushes the valve 26 against the valve seat 27, and the system is ready for operation.

 In the "setup" mode, the system is operated using the control button 38. When you click on it, one of the end cavities, for example, the control valve 2 communicates with the cavity 17 of the hydraulic capacity 13, and the hydraulic cylinder 4 makes a working (idle) stroke.

 The design of the control valve makes it possible to ensure the operation of the executive hydraulic cylinder both when the cam (copier) of the software device 12 is exposed to it, and if it is absent. The presence of a spring 40 in the control valve provides a message to the end cavity of its spool with a hydraulic capacity 13 when the cam (copier) does not act on the slider 41. In addition, by pulling the button 38 from the control valve, the fluid is supplied under pressure into the end cavity of the control valve of the actuating hydraulic cylinder and preset movement of the actuating hydraulic cylinder.

 The technical and economic efficiency of the proposed device is to increase the service life of the working fluid and the system, to reduce the time it takes to service the system and save working fluid.

Claims (1)

 A hydraulic press control system comprising a power source communicating via hydraulic distributors with executive hydraulic cylinders, a control pump connected to the end cavities of the hydraulic actuator hydraulic distributors, a drive on the rod of which is located a software device for switching control hydraulic distributors, a hydraulic fluid for the working fluid, characterized in that the hydraulic fluid for the working fluid is made in the form of a housing with a piston installed in it with the formation of the rod and pores the cavity, and is equipped with a piston drive, a breather filter and a locking device connected to a hydraulic line for collecting leaks and hydraulic fluid for the working fluid, the hydraulic piston drive for the hydraulic fluid is made in the form of a hydraulic cylinder with a four-way two-position distributor connected by pipelines to the control pump and hydraulic reservoir for working fluid, and at the end of the stem of the hydraulic cylinder for hydraulic fluid mounted valve, which is installed with a gap in the piston between the seat and the stop for draining brane drainage of leaks from the rod end of the piston in the accumulator tank.

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