CN219838242U - Hydraulic control system of overhead oil cylinder press - Google Patents

Abstract

The hydraulic control system of the overhead oil cylinder press comprises four hydraulic cylinders, a first reversing valve, a second reversing valve, a first hydraulic control one-way valve, a second hydraulic control one-way valve, an overflow valve and a power source; the first reversing valve oil inlet is connected with the constant pressure variable pump, the oil return port is connected with the oil return pipe, the first working oil port is connected with the first hydraulic control one-way valve oil inlet, the first hydraulic control one-way valve oil outlet is connected with the hydraulic cylinder upper cavity and the overflow valve oil inlet, the overflow valve oil outlet is connected with the oil return pipe, the first reversing valve second working oil port is connected with the second hydraulic control one-way valve oil inlet and the first hydraulic control one-way valve control oil port, the second hydraulic control one-way valve oil outlet is connected with the hydraulic cylinder lower cavity and the pressure sensor, the pressure sensor can control the overpressure stop of the press through the control system, the oil inlet pipe is connected with the second reversing valve oil inlet, the second reversing valve oil return port is connected with the oil return pipe, and the second reversing valve working oil port is connected with the second hydraulic control one-way valve control oil port; the first reversing valve and the second reversing valve are respectively a three-position four-way Y-shaped reversing valve and a two-position four-way electromagnetic reversing valve.

Description

Hydraulic control system of overhead oil cylinder press

Technical Field

The present utility model relates to a hydraulic control system for a press.

Background

The existing press with the oil cylinders arranged at the top is characterized in that four oil cylinders are arranged at the upper positions of upright posts at four corners of the press, each oil cylinder body is connected with an upper cross beam of the press respectively, a piston rod is connected with the upright posts, the upper cross beams are supported on adjusting nuts on the upright posts, the upper cross beams are connected with sliding blocks through crank connecting rods, an upper die is arranged on the lower plane of the sliding blocks, when oil is filled into lower cavities of the four oil cylinders, oil cylinder pistons and the upright posts are kept motionless, the oil cylinder bodies and the upper beams move downwards (or have a downward movement trend) with the sliding blocks and the upper die, pressurization is started when the pressure reaches the adjusting nuts, the pressure is maintained when the set pressure is reached, and the position of the bottom dead center of the sliding blocks is maintained, so that the press can work normally. When the upper cavities of the four oil cylinders are filled with oil, the oil cylinder piston and the upright post are kept motionless, the oil cylinder body and the upper beam carry the sliding block and the upper die to move upwards and separate from the adjusting nut, and the sliding block stops when being at the upper dead point, so that the adjusting nut can be adjusted, and the die loading height can be adjusted, and the die can be installed and replaced. In addition, when the pressure center of the die is inconsistent with the pressure center of the slide block, namely unbalanced load can occur, and when the unbalanced load exceeds the allowable range, if the press is not alarmed or stopped, the die and the press can be directly damaged.

Disclosure of Invention

The utility model aims to solve the technical problem of providing a hydraulic control system of a press machine, which can conveniently adjust the die-filling height and better protect the press machine and a die.

The technical scheme adopted for solving the technical problems is as follows:

the hydraulic control system of the overhead oil cylinder press comprises four hydraulic cylinders, a first reversing valve, a first hydraulic control one-way valve, an overflow valve, a second reversing valve, a second hydraulic control one-way valve, a pressure sensor and a constant pressure variable pump; the constant-pressure variable pump is connected with an oil inlet pipe and is used for conveying hydraulic oil, the oil inlet pipe is connected with an oil inlet of a first reversing valve, an oil return port of the first reversing valve is connected with an oil return pipe, a first working oil port of the first reversing valve is connected with an oil inlet of a first hydraulic control one-way valve, an oil outlet of the first hydraulic control one-way valve is connected with an upper cavity of a hydraulic cylinder and is also connected with an oil inlet of an overflow valve, an oil outlet of the overflow valve is connected with the oil return pipe, a second working oil port of the first reversing valve is connected with an oil inlet of a second hydraulic control one-way valve and is also connected with a control oil port of the first hydraulic control one-way valve, an oil outlet of the second hydraulic control one-way valve is connected with a lower cavity of the hydraulic cylinder and is also connected with a pressure sensor, and the pressure sensor sends a signal to a press control system after exceeding a set pressure value so that the press stops working; the oil inlet pipe is connected with an oil inlet of a second reversing valve, an oil return port of the second reversing valve is connected with an oil return pipe, and a working oil port of the second reversing valve is connected with a control oil port of a second hydraulic control one-way valve; the first reversing valve is a three-position four-way Y-shaped electromagnetic reversing valve, and the second reversing valve is a two-position four-way electromagnetic reversing valve or a two-position three-way electromagnetic reversing valve.

Preferably, the lower cavity of each hydraulic cylinder is connected with a pressure sensor and a hydraulic control one-way valve, and the pressure sensor sends a signal to the control system of the press after exceeding a set pressure value, so that the press stops working, and the pressure of each hydraulic cylinder can be monitored, and the control is more flexible and comprehensive.

Preferably, the oil inlet pipe is also connected with a pressure gauge, so that the pressure in the oil inlet pipe can be intuitively displayed.

Compared with the prior art, the utility model has the advantages that: the lower cavity of each hydraulic cylinder is respectively connected with a hydraulic control one-way valve and a pressure sensor, when the press is stamped, the pressure sensor can independently detect the pressure of the lower cavity of each hydraulic cylinder, if overpressure exists, the pressure sensor transmits signals to the press control system, and the control system controls the press to stop working, so that the press and the die are better protected.

Drawings

Fig. 1 is a schematic diagram of a hydraulic control system of a top-mounted ram press according to an embodiment of the present utility model.

Description of the embodiments

The utility model is described in further detail below with reference to the drawings and examples.

As shown in fig. 1, the hydraulic control system of the overhead oil cylinder press comprises four hydraulic cylinders 1, a first reversing valve 2, a first hydraulic control one-way valve 3, an overflow valve 4, a second reversing valve 5, a second hydraulic control one-way valve 6, a pressure sensor 7 and a constant pressure variable pump 8.

The constant pressure variable pump 8 is responsible for providing pressure oil required by a power guarantee hydraulic control system, the constant pressure variable pump is connected with an oil inlet pipe 81, the oil inlet pipe 81 is connected with an oil inlet of a first reversing valve 2, an oil return port of the first reversing valve 2 is connected with an oil return pipe 82 of the hydraulic control system, a first working oil port of the first reversing valve 2 is connected with an oil inlet of a first hydraulic control one-way valve 3, an oil outlet of the first hydraulic control one-way valve 3 is connected with an upper cavity of the hydraulic cylinder 1 and is also connected with an oil inlet of an overflow valve 4, an oil outlet of the overflow valve 4 is connected with an oil return pipe 82 of the hydraulic control system, a second working oil port of the first reversing valve 2 is connected with an oil inlet of a second hydraulic control one-way valve 6 and is also connected with a control oil port of the first hydraulic control one-way valve 3, an oil outlet of the second hydraulic control one-way valve 6 is connected with a lower cavity of the hydraulic cylinder 1 and is also connected with a pressure sensor 7, an oil inlet of the first working oil port of the second reversing valve 5 is connected with an oil inlet of the second reversing valve 5, an oil return port of the second reversing valve 5 is connected with the oil return pipe 82 of the hydraulic control system and the second working oil port of the second reversing valve 5 is connected with the second hydraulic control one-way valve 6.

The lower chamber of each hydraulic cylinder 1 is connected with a pressure sensor 7 and a pilot operated check valve 6.

The oil inlet pipe 81 is also connected with a pressure gauge 9, and the pressure gauge 9 is used for displaying the working pressure of the hydraulic control system.

The first reversing valve 2 is a three-position four-way Y-shaped electromagnetic reversing valve.

The second reversing valve 5 is a two-position four-way electromagnetic reversing valve or a two-position three-way electromagnetic reversing valve.

The working principle of the hydraulic control system of the press is as follows:

when the die-filling height of the press slide block needs to be adjusted, the left electromagnet of the three-position four-way Y-shaped electromagnetic directional valve 2 is electrified, the upper cavity of the hydraulic cylinder 1 is filled with oil, so that the upper cross beam is separated from the adjusting nut upwards, the electromagnet of the two-position four-way electromagnetic directional valve 5 is electrified, the oil inlet of the electromagnetic directional valve is communicated with the working oil port, the second hydraulic control one-way valve 6 is used for controlling the oil port to have pressure input, the second hydraulic control one-way valve 6 is opened, and an oil return path is communicated; stopping the upper beam after reaching a set position, wherein the left electromagnet of the three-position four-way Y-shaped electromagnetic directional valve 2 is powered off, the three-position four-way Y-shaped electromagnetic directional valve 2 is positioned in the middle position, the electromagnet of the two-position four-way electromagnetic directional valve 5 is powered off, and the hydraulic control one-way valve 3 plays a role in that the upper cavity of the hydraulic cylinder 1 is in a pressure maintaining state, so that the position of the upper beam is ensured to be constant; after the adjusting nut is adjusted to a required position, the right electromagnet of the three-position four-way Y-shaped electromagnetic directional valve 2 is electrified, the lower cavity of the hydraulic cylinder 1 is filled with oil, the upper cross beam is enabled to downwards move until the adjusting nut is contacted to be limited to downwards move, the pressure of the lower cavity is maintained after the pressure of the lower cavity reaches a set value, the right electromagnet of the three-position four-way Y-shaped electromagnetic directional valve 2 is deenergized, and the three-position four-way Y-shaped electromagnetic directional valve 2 is positioned in the middle position until the die filling height is adjusted.

When the press works in normal stamping, the three-position four-way Y-shaped electromagnetic directional valve 2 is positioned in the middle position, the constant pressure variable pump 8 stops oil supply, and the second hydraulic control one-way valve 6 plays a role in keeping the lower cavity of the hydraulic cylinder 1 in a pressure maintaining state, so that the position of the bottom dead center of the sliding block can be ensured, and the press can complete stamping through the up-and-down motion of the sliding block.

In the stamping process, when unbalanced load is serious, the sliding block is subjected to a reaction force to generate an inclination phenomenon, so that the upper cross beam is forced to incline, the pressure of the lower cavity of one or more hydraulic cylinders is increased and exceeds the set pressure value of the pressure sensor, and therefore the pressure sensor can send a signal to the press control system, and the press control system stops working of the press. Because the pressure sensors 7 are arranged on the oil paths of the lower cavities of the four hydraulic cylinders, each pressure sensor 7 can independently detect the pressure of the lower cavity of each hydraulic cylinder, and the corresponding pressure sensor 7 can send a signal to a control system of the press to avoid damage to the press and the die.

Claims (3)

1. The hydraulic control system of the overhead oil cylinder press is characterized in that: the hydraulic control system comprises four hydraulic cylinders, a first reversing valve, a first hydraulic control one-way valve, an overflow valve, a second reversing valve, a second hydraulic control one-way valve, a pressure sensor and a constant pressure variable pump; the constant-pressure variable pump is connected with an oil inlet pipe and is used for conveying hydraulic oil, the oil inlet pipe is connected with an oil inlet of a first reversing valve, an oil return port of the first reversing valve is connected with an oil return pipe, a first working oil port of the first reversing valve is connected with an oil inlet of a first hydraulic control one-way valve, an oil outlet of the first hydraulic control one-way valve is connected with an upper cavity of a hydraulic cylinder and is also connected with an oil inlet of an overflow valve, an oil outlet of the overflow valve is connected with the oil return pipe, a second working oil port of the first reversing valve is connected with an oil inlet of a second hydraulic control one-way valve and is also connected with a control oil port of the first hydraulic control one-way valve, an oil outlet of the second hydraulic control one-way valve is connected with a lower cavity of the hydraulic cylinder and is also connected with a pressure sensor, and the pressure sensor sends a signal to a press control system after exceeding a set pressure value so that the press stops working; the oil inlet pipe is connected with an oil inlet of a second reversing valve, an oil return port of the second reversing valve is connected with an oil return pipe, and a working oil port of the second reversing valve is connected with a control oil port of a second hydraulic control one-way valve; the first reversing valve is a three-position four-way Y-shaped electromagnetic reversing valve, and the second reversing valve is a two-position four-way electromagnetic reversing valve or a two-position three-way electromagnetic reversing valve.

2. The hydraulic control system of the overhead ram press of claim 1, wherein: the lower cavity of each hydraulic cylinder is connected with a pressure sensor and a hydraulic control one-way valve, and the pressure sensor sends a signal to a control system of the press after exceeding a set pressure value, so that the press stops working.

3. The hydraulic control system of the overhead ram press of claim 1, wherein: the oil inlet pipe is also connected with a pressure gauge.