Hydraulic control system for fixing die and forming die

Abstract

The utility model discloses a hydraulic control system for fixing a die, which relates to the technical field of hydraulic control systems and comprises a three-position reversing valve, a rod cavity oil way, a rodless cavity oil way, a first hydraulic control one-way valve, a second hydraulic control one-way valve, a balance valve, an oil inlet pipeline and an oil return pipeline. When each oil cylinder is controlled to clamp, the three-position reversing valve is in a first state, so that oil enters from the rodless cavity oil way, oil returns from the rod cavity oil way, the pressure difference of the oil ways is reduced through the balance valve, and the impact on a die is reduced; when the oil cylinders are controlled to be loosened, the three-position reversing valve is in a second state, and oil enters the rod cavity oil way and returns the rodless cavity oil way; when pressure maintaining of the oil cylinders is controlled, the three-position reversing valve is in a third state, oil ways are interlocked through the first hydraulic control one-way valve and the second hydraulic control one-way valve, and the clamping state is maintained; the utility model further discloses a forming die, the forming die comprises the hydraulic control system used for fixing the die and the die, and clamping and loosening during die replacement are achieved through the hydraulic control system used for fixing the die.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic control, in particular to a hydraulic control system for fixing a mold and a forming mold. Background Art

[0002] When replacing the mold, the traditional mold replacement requires manual operation to replace the mold. Tools are used to disassemble the original mold and re-fix the new mold. The operation is cumbersome and time-consuming during the mold replacement process. Therefore, the controlled hydraulic mold replacement technology has emerged. Chinese Patent Application CN117231597A discloses a hydraulic control system and its control method. When this hydraulic control system is used to fix the mold, during the mold clamping and fixing process, due to the excessive pressure difference between the rod chamber and the rodless chamber of the oil cylinder, the impact force of the oil cylinder on the mold during clamping is too large, which is likely to cause damage to the mold. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a hydraulic control system for fixing a mold and a forming mold to solve the problems existing in the above-mentioned prior art, reduce the impact of the piston rod on the mold during the clamping and fixing process, avoid damage to the mold, and also realize the pressure holding of the oil cylinder, maintain the clamping state of the piston rod on the mold, and the pressure in the oil circuit is more stable and the energy consumption is less.

[0004] To achieve the above purpose, the utility model provides the following solution:

[0005] The present utility model provides a hydraulic control system for fixing a mold, which includes a three-position reversing valve that can switch between a first state, a second state, and a third state; a rod chamber oil circuit, one end of which is used to communicate with the three-position reversing valve, and the other end is used to communicate with the rod chambers of each oil cylinder; a rodless chamber oil circuit, one end of which is used to communicate with the three-position reversing valve, and the other end is used to communicate with the rodless chambers of each oil cylinder; a first hydraulic check valve and a second hydraulic check valve, the first hydraulic check valve is arranged on the rod chamber oil circuit, the first oil inlet of the first hydraulic check valve is communicated with the three-position reversing valve, the first oil outlet of the first hydraulic check valve is communicated with each rod chamber, the first control oil port of the first hydraulic check valve is communicated with the rodless chamber oil circuit located between the three-position reversing valve and the second hydraulic check valve, the second hydraulic check valve is arranged on the rodless chamber oil circuit, the second oil inlet of the second hydraulic check valve is communicated with the three-position reversing valve, the second oil outlet of the second hydraulic check valve is communicated with each rodless chamber, and the second control oil port of the second hydraulic check valve is communicated with the rod chamber oil circuit located between the three-position reversing valve and the first hydraulic check valve; a balance valve, the balance valve is arranged on the rod chamber oil circuit between the first hydraulic check valve and each rod chamber, the inlet of the balance valve is communicated with the first oil outlet of the first hydraulic check valve, the outlet of the balance valve is communicated with each rod chamber, and the pilot port of the balance valve is communicated with each rod chamber; an oil inlet pipeline, which is used to communicate with the three-position reversing valve; and an oil return pipeline, which is used to communicate with the three-position reversing valve; when the three-position reversing valve is in the first state, the oil inlet pipeline is communicated with the rodless chamber oil circuit, and the rod chamber oil circuit is communicated with the oil return pipeline; when the three-position reversing valve is in the second state, the oil inlet pipeline is communicated with the rod chamber oil circuit, and the rodless chamber oil circuit is communicated with the oil return pipeline; when the three-position reversing valve is in the third state, the oil inlet pipeline is closed, and the oil return pipeline is connected to the rod chamber oil circuit and the rodless chamber oil circuit.

[0006] Preferably, it further includes at least one oil cylinder, and the piston rods of each oil cylinder are used to connect the moving part of the mold.

[0007] Preferably, the three-position reversing valve has an oil inlet, an oil return port, a first working port, and a second working port. When the three-position reversing valve is in the first state, the oil inlet is communicated with the first working port, and the second working port is communicated with the oil return port; when the three-position reversing valve is in the second state, the oil inlet is communicated with the second working port, and the first working port is communicated with the oil return port; when the three-position reversing valve is in the third state, the oil inlet is closed, and the first working port and the second working port are communicated with the oil return port.

[0008] Preferably, the three-position directional valve further has a drain port, and the drain port is connected and communicated with a drain pipeline.

[0009] Preferably, it further includes a first relief valve and a second relief valve. The first relief valve is arranged on the oil path between the first pilot-operated check valve and the balance valve to control the pressure of the rod chamber oil path, and the second relief valve is arranged on the oil path between the second pilot-operated check valve and the rodless chamber to control the pressure of the rodless chamber oil path.

[0010] Preferably, the three-position directional valve adopts any one of a manual three-position directional valve, an electromagnetic three-position directional valve, and an electro-hydraulic three-position directional valve.

[0011] Preferably, the first relief valve and the second relief valve are direct-acting relief valves, and the oil drainage mode of the direct-acting relief valve is external drainage.

[0012] Preferably, it further includes a first pressure measuring joint, a second pressure measuring joint, and a third pressure measuring joint. The first pressure measuring joint is communicated with the rod chamber oil path, the second pressure measuring joint is communicated with the rodless chamber oil path, the third pressure measuring joint is communicated with the oil inlet pipeline, and the first pressure measuring joint, the second pressure measuring joint, and the third pressure measuring joint are used to connect a pressure gauge.

[0013] The present utility model provides a forming die, which includes a hydraulic control system and a die for fixing the die as described in any one of the above, and the die includes a moving part.

[0014] The present utility model has achieved the following technical effects compared with the prior art:

[0015] The hydraulic control system and the forming die for fixing the die provided by the utility model, when controlling each oil cylinder to clamp, control the three-way directional valve to be in the first state, so that the oil inlet pipeline is communicated with the rodless cavity oil circuit, the rodless cavity oil circuit is filled with oil, and the rod cavity oil circuit is communicated with the oil return pipeline, and the oil in the rod cavity oil circuit returns. The initial oil pressure in the rod cavity oil circuit is relatively small. At this time, the pressure in the rodless cavity oil circuit is much greater than the pressure in the rod cavity oil circuit. The oil pressure in the rod cavity oil circuit cannot reach the pressure value set by the pilot port, and the balance valve blocks the oil from flowing from the outlet to the inlet, and the piston rod cannot move. When the oil pressure in the rod cavity oil circuit reaches the pressure value set by the pilot port, the balance valve allows the oil to flow from the outlet to the inlet to reduce the pressure difference between the rodless cavity oil circuit and the rod cavity oil circuit, thereby controlling the extension speed of the piston rod and reducing the impact of the piston rod on the die during the clamping process, avoiding damage to the die; by arranging a first hydraulic control one-way valve on the rod cavity oil circuit and the first control oil port is communicated with the rodless cavity oil circuit, and arranging a second hydraulic control one-way valve on the rodless cavity oil circuit and the second control oil port is communicated with the rod cavity oil circuit. When the three-way directional valve is in the third state, the pressures in the rod cavity oil circuit and the rodless cavity oil circuit are the same, there is no pressure difference, and the oil in the first control oil port and the second control oil port cannot reach the preset pressure value. Therefore, the first hydraulic control one-way valve blocks the oil from flowing from the first oil outlet to the first oil inlet, and the second hydraulic control one-way valve blocks the oil from flowing from the second oil outlet to the second oil inlet, so that the rod cavity oil circuit and the rodless cavity oil circuit are interlocked to realize the pressure holding of each oil cylinder, keep the die in a clamped state, and this pressure holding method does not require the intervention of energy-consuming equipment such as auxiliary pumps and accumulators, and the pressures in the rod cavity oil circuit and the rodless cavity oil circuit are more stable.

[0016] Further, the three-way directional valve also has a leakage port, and the leakage port is connected and communicated with a leakage pipeline. When the oil return pipeline returns oil, it is communicated with the three-way directional valve through the leakage pipeline, which can reduce the back pressure of the oil return pipeline, prevent the excessive resistance of the three-way directional valve during commutation, improve the sensitivity during commutation, and ensure the normal operation of the system. Brief Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic diagram of the hydraulic cylinder control system of the present invention when the three-way directional valve is in the first state;

[0019] Figure 2 It is a schematic diagram of the hydraulic cylinder control system of the present invention when the three-way directional valve is in the second state;

[0020] Figure 3 This is a schematic diagram of the hydraulic cylinder control system of the present utility model when the three-way directional valve is in the third state;

[0021] In the figure: 1 - three-way directional valve; 11 - first state; 12 - second state; 13 - third state; 2 - oil cylinder; 21 - rod chamber; 211 - first pressure measuring joint; 22 - rodless chamber; 221 - second pressure measuring joint; 3 - rod chamber oil circuit; 31 - balance valve; 32 - first pilot-operated check valve; 33 - first direct-acting relief valve; 4 - rodless chamber oil circuit; 42 - second pilot-operated check valve; 43 - second direct-acting relief valve; 5 - inlet pipeline; 51 - third pressure measuring joint; 6 - return pipeline; 7 - external leakage pipeline; J1 - first inlet port; R1 - first outlet port; K1 - first control oil port; J2 - second inlet port; R2 - second outlet port; K2 - second control oil port; E - inlet; F - outlet; X - pilot port; B - inlet port; T - return port; A - first working port; B - second working port; Y - external leakage port. Specific embodiments

[0022] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0023] The purpose of the present utility model is to provide a hydraulic control system and a forming die for fixing a die, so as to solve the problems existing in the above-mentioned prior art, reduce the impact of the piston rod on the die during the clamping and fixing process, avoid damage to the die, and also achieve the pressure holding of the oil cylinder, maintain the clamping state of the piston rod on the die, and the pressure in the oil circuit is more stable and the energy consumption is less.

[0024] To make the above objects, features, and advantages of the present utility model more obvious and understandable, the present utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0025] Embodiment 1

[0026] This embodiment provides a hydraulic control system for fixing a die, as Figures 1 to 3As shown in the figure, it includes a three-position directional control valve 1, a rod chamber oil circuit 3, a rodless chamber oil circuit 4, a first pilot-operated check valve 32, a second pilot-operated check valve 42, a balance valve 31, an oil inlet pipeline 5 and an oil return pipeline 6. The three-position directional control valve 1 can switch between a first state 11, a second state 12 and a third state 13. One end of the rod chamber oil circuit 3 is used to communicate with the three-position directional control valve 1, and the other end is used to communicate with each rod chamber 21. One end of the rodless chamber oil circuit 4 is used to communicate with the three-position directional control valve 1, and the other end is used to communicate with each rodless chamber 22. The first pilot-operated check valve 32 is arranged on the rod chamber oil circuit 3, wherein the first oil inlet J1 of the first pilot-operated check valve 32 communicates with the three-position directional control valve 1, the first oil outlet R1 of the first pilot-operated check valve 32 communicates with each rod chamber 21, and the first control oil port K1 of the first pilot-operated check valve 32 communicates with the rodless chamber oil circuit 4 located between the three-position directional control valve 1 and the second pilot-operated check valve 42. The second pilot-operated check valve 42 is arranged on the rodless chamber oil circuit 4, the second oil inlet J2 of the second pilot-operated check valve 42 communicates with the three-position directional control valve 1, the second oil outlet R2 of the second pilot-operated check valve 42 communicates with each rodless chamber 22, and the second control oil port K2 of the second pilot-operated check valve 42 communicates with the rod chamber oil circuit 3 located between the three-position directional control valve 1 and the first pilot-operated check valve 32. The balance valve 31 is arranged on the rod chamber oil circuit 3 between the first pilot-operated check valve 32 and each rod chamber 21. Among them, the inlet E of the balance valve 31 communicates with the first oil outlet of the first pilot-operated check valve 32, the outlet F of the balance valve 31 communicates with each rod chamber 21, and the pilot port X of the balance valve 31 communicates with each of the rod chambers 21. The oil inlet pipeline 5 is used to communicate with the three-position directional control valve 1 to supply oil to the hydraulic control system for fixing the mold, and the oil return pipeline 6 is used to communicate with the three-position directional control valve 1 to return oil from the hydraulic control system for fixing the mold. When controlling each oil cylinder 2 to clamp, by controlling the three-position directional control valve 1 to be in the first state 11, the oil inlet pipeline 5 is communicated with the rodless chamber oil circuit 4, the rodless chamber oil circuit 4 is supplied with oil, and the rod chamber oil circuit 3 is communicated with the oil return pipeline 6, and the rod chamber oil circuit 3 returns oil, so that the rodless chamber 22 of the oil cylinder 2 is supplied with oil and the rod chamber 21 discharges oil. The oil pressure in the rodless chamber 22 increases and the oil pressure in the rod chamber 21 decreases, pushing the piston rod to extend to realize the clamping process of the mold. The initial state oil pressure of the rod chamber oil circuit 3 is small. At this time, the pressure of the rodless chamber oil circuit 4 is much greater than the pressure of the rod chamber oil circuit 3. The oil pressure in the rod chamber oil circuit 3 cannot reach the pressure value set by the pilot port X, and the balance valve 31 blocks the oil from flowing from the outlet F to the inlet E, and the piston rod cannot move. When the oil pressure in the rod chamber oil circuit 3 reaches the pressure value set by the pilot port X, the balance valve 31 allows the oil to flow from the outlet F to the inlet E to reduce the pressure difference between the rodless chamber oil circuit 4 and the rod chamber oil circuit 3, thereby controlling the extension speed of the piston rod and reducing the impact of the piston rod on the mold during the clamping process, avoiding damage to the mold;When controlling the relaxation of each oil cylinder 2, by controlling the three-position directional control valve 1 to be in the second state 12, the oil inlet pipeline 5 is connected to the rodless cavity oil circuit 3, and the rodless cavity oil circuit 4 is connected to the oil return pipeline 6. The rodless cavity 22 of the oil cylinder is filled with oil and the rod cavity 21 discharges oil. The oil pressure in the rodless cavity 22 increases and the oil pressure in the rod cavity 21 decreases, pushing the piston rod to retract to realize the process of relaxing the mold. At this time, the balance valve 31 allows the oil to flow from the inlet E to F. When controlling the pressure holding of each oil cylinder, by controlling the three-position directional control valve 1 to be in the third state 13, the oil inlet pipeline 5 is closed, and the oil return pipeline 6 is connected to the rod cavity oil circuit 3 and the rodless cavity oil circuit 4. At this time, the pressures in the rod cavity oil circuit 3 and the rodless cavity oil circuit 4 are the same, there is no pressure difference, and the oil in the first control oil port K1 and the second control oil port K2 cannot reach the preset pressure values. Therefore, the first pilot-operated check valve 32 cuts off the oil from flowing from the first oil outlet R1 to the first oil inlet J1, and the second pilot-operated check valve 32 cuts off the oil from flowing from the second oil outlet R2 to the second oil inlet J2, interlocking the rod cavity oil circuit 3 and the rodless cavity oil circuit 4 to realize the pressure holding of each oil cylinder, maintaining the clamping state of the mold, and this pressure holding method does not require the intervention of energy-consuming equipment such as auxiliary pumps and accumulators, and the pressures in the rod cavity oil circuit and the rodless cavity oil circuit are stable.

[0027] In another implementation manner of this embodiment, the hydraulic control system for fixing the mold further includes at least one oil cylinder 2, and the piston rod of each oil cylinder 2 is used to connect the moving part of the mold.

[0028] In another implementation manner of this embodiment, the three-position directional control valve includes an oil inlet P, an oil return port T, an external leakage port Y, a first working port A, and a second working port B. When the three-position directional control valve is in the first state, the oil inlet P is connected to the first working port A, and the second working port B is connected to the oil return port T and the external leakage port Y, so that the oil inlet pipeline is connected to the rodless cavity oil circuit, and the rod cavity oil circuit is connected to the oil return pipeline and the external leakage pipeline to realize the process of clamping the mold. When the three-position directional control valve is in the second state, the oil inlet P is connected to the second working port B, and the first working port A is connected to the oil return port T and the external leakage port Y, so that the oil inlet pipeline is connected to the rod cavity oil circuit, and the rodless cavity oil circuit is connected to the oil return pipeline and the external leakage pipeline to realize the process of relaxing the mold. When the three-position directional control valve is in the third state, the oil inlet P is closed, and the first working port A and the second working port B are connected to the oil return port T, so that the oil inlet pipeline is closed, and the oil return pipeline is connected to the rod cavity oil circuit and the rodless cavity oil circuit to maintain the clamping state of the mold.

[0029] In another implementation manner of this embodiment, the three-position directional control valve 1 also has an external leakage port Y, and the external leakage port Y is connected and communicated with an external leakage pipeline 7. When discharging oil through the oil return port T, it prevents the excessive back pressure during oil return from causing excessive commutation resistance of the three-position directional control valve 1, improves the sensitivity during commutation, and ensures the normal operation of the system.

[0030] In another implementation manner of this embodiment, the hydraulic control system for fixing the mold further includes a first overflow valve 33 and a second overflow valve 43. The first overflow valve 33 is arranged on the oil path between the first hydraulic control check valve 32 and the balance valve 31 to control the pressure of the rod chamber oil path 3 within a safe range. The second overflow valve 43 is arranged on the oil path between the second hydraulic control check valve 42 and the rodless chamber 22 to control the pressure of the rodless chamber oil path 4 within a safe range, preventing the hydraulic control system from being damaged due to overload.

[0031] In another implementation manner of this embodiment, the three-position reversing valve 1 can be any one of a manual three-position reversing valve, an electromagnetic three-position reversing valve, and an electro-hydraulic three-position reversing valve.

[0032] In another implementation manner of this embodiment, the three-position reversing valve 1 can be any one of a three-position four-way reversing valve, a three-position five-way reversing valve, and a three-position six-way reversing valve.

[0033] In another implementation manner of this embodiment, the first overflow valve 33 and the second overflow valve 43 are direct-acting overflow valves, and the oil drainage method is external drainage. In the external drainage mode, when the hydraulic pressure in the system exceeds the preset pre-tightening force of the valve core spring, the working oil in the system will directly flow out from the channel at the top of the valve core to the fuel tank, thereby playing a role in regulating the pressure of the hydraulic control system.

[0034] In another implementation manner of this embodiment, it further includes a first pressure measuring joint 211, a second pressure measuring joint 221, and a third pressure measuring joint 51. The first pressure measuring joint 211 is connected to each rod chamber 21, the second pressure measuring joint 221 is connected to each rodless chamber 22, and the third pressure measuring joint 51 is connected to the oil inlet pipeline 5. The first pressure measuring joint 211, the second pressure measuring joint 221, and the third pressure measuring joint 51 are used to connect a pressure gauge to monitor the pressure in the system to ensure the safety of the hydraulic control system.

[0035] Embodiment 2

[0036] This embodiment provides a forming mold, including the hydraulic control system for fixing the mold and the mold in Embodiment 1. The mold includes a moving part. The clamping and relaxation during mold replacement are realized through the hydraulic control system for fixing the mold, reducing the impact of the piston rod on the mold during the clamping and fixing process, avoiding damage to the mold, and also being able to realize the pressure holding of the oil cylinder, maintaining the clamping state of the piston rod on the mold, and having more stable pressure in the oil path and less energy consumption.

[0037] Specific examples are used in the present utility model to elaborate on the principle and implementation manner of the present utility model. The description of the above embodiments is only used to help understand the method and its core idea of the present utility model; at the same time, for those of ordinary skill in the art, according to the idea of the present utility model, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present utility model.

Claims

1. A hydraulic control system for fixing a mold, characterized in that, including a three-position directional control valve capable of switching between a first state, a second state and a third state; a rod chamber oil passage, one end of which is used to communicate with the three-position directional control valve and the other end of which is used to communicate with the rod chambers of each oil cylinder; a rodless chamber oil passage, one end of which is used to communicate with the three-position directional control valve and the other end of which is used to communicate with the rodless chambers of each oil cylinder; a first pilot-operated check valve and a second pilot-operated check valve, the first pilot-operated check valve being arranged on the rod chamber oil passage, a first oil inlet of the first pilot-operated check valve communicating with the three-position directional control valve, a first oil outlet of the first pilot-operated check valve communicating with each rod chamber, a first control oil port of the first pilot-operated check valve communicating with the rodless chamber oil passage located between the three-position directional control valve and the second pilot-operated check valve, the second pilot-operated check valve being arranged on the rodless chamber oil passage, a second oil inlet of the second pilot-operated check valve communicating with the three-position directional control valve, a second oil outlet of the second pilot-operated check valve communicating with each rodless chamber, and a second control oil port of the second pilot-operated check valve communicating with the rod chamber oil passage located between the three-position directional control valve and the first pilot-operated check valve; a balance valve arranged on the rod chamber oil passage between the first pilot-operated check valve and each rod chamber, an inlet of the balance valve communicating with the first oil outlet of the first pilot-operated check valve, an outlet of the balance valve communicating with each rod chamber, and a pilot port of the balance valve communicating with each rod chamber; an oil inlet pipeline for communicating with the three-position directional control valve; and an oil return pipeline for communicating with the three-position directional control valve; when the three-position directional control valve is in the first state, the oil inlet pipeline communicates with the rodless chamber oil passage, and the rod chamber oil passage communicates with the oil return pipeline; when the three-position directional control valve is in the second state, the oil inlet pipeline communicates with the rod chamber oil passage, and the rodless chamber oil passage communicates with the oil return pipeline; when the three-position directional control valve is in the third state, the oil inlet pipeline is closed, and the oil return pipeline is connected to the rod chamber oil passage and the rodless chamber oil passage.

2. The hydraulic control system for fixing a mold according to claim 1, wherein It further includes at least one oil cylinder, and the piston rods of each oil cylinder are used to connect the moving part of the mold.

3. The hydraulic control system for fixing a mold according to claim 1, characterized in that, The three-position directional control valve has an oil inlet, an oil return port, a first working port and a second working port. When the three-position directional control valve is in the first state, the oil inlet and the first working port are communicated, and the second working port and the oil return port are communicated; when the three-position directional control valve is in the second state, the oil inlet and the second working port are communicated, and the first working port and the oil return port are communicated. When the three-position directional control valve is in the third state, the oil inlet is closed, and the first working port and the second working port are communicated with the oil return port.

4. The hydraulic control system for fixing a mold according to claim 1, characterized in that, The three-position directional control valve further has an external leakage port, and the external leakage port is connected and communicated with an external leakage pipeline.

5. The hydraulic control system for fixing a mold according to claim 1, characterized in that, It further includes a first overflow valve and a second overflow valve. The first overflow valve is arranged on the oil path between the first pilot-operated check valve and the balance valve to control the pressure of the rod chamber oil path, and the second overflow valve is arranged on the oil path between the second pilot-operated check valve and the rodless chamber to control the pressure of the rodless chamber oil path.

6. The hydraulic control system for fixing a mold according to claim 1, characterized in that, The three-position reversing valve adopts any one of a manual three-position reversing valve, an electromagnetic three-position reversing valve, and an electro-hydraulic three-position reversing valve.

7. The hydraulic control system for fixing a mold according to claim 5, characterized in that, The first overflow valve and the second overflow valve are direct-acting overflow valves, and the oil drainage mode of the direct-acting overflow valve is external leakage type.

8. The hydraulic control system for fixing a mold according to claim 1, characterized in that, It further includes a first pressure measuring joint, a second pressure measuring joint, and a third pressure measuring joint. The first pressure measuring joint is communicated with the rod chamber oil path, the second pressure measuring joint is communicated with the rodless chamber oil path, the third pressure measuring joint is communicated with the oil inlet pipeline, and the first pressure measuring joint, the second pressure measuring joint, and the third pressure measuring joint are used to connect a pressure gauge.

9. A molding die, characterized in that, It includes the hydraulic control system and the mold for fixing the mold according to any one of claims 1 to 8, and the mold includes a moving part.

Images