Sheet type hydraulic valve group of vulcanizing machine

Abstract

A plate type valve group of a vulcanizing machine comprises a pressure and flow double-proportional valve and a plate type valve group, the pressure and flow double-proportional valve is modified, so that the plate type valve group can be mounted on two sides of the pressure and flow double-proportional valve, an execution end is endowed with more functions through a small inserting block, and the manufacturing cost is greatly reduced while the structure is optimized.

Description

Technical Field

[0001] The invention relates to a hydraulic control valve, in particular to a vulcanizing machine plate type hydraulic valve group. Background Art

[0002] The hydraulic system of a vulcanizing machine is a relatively complex hydraulic control system. The control oil circuit it uses is complex, so it often requires complex pipelines and oil blocks to implement, which is not only costly, but also occupies a large space and has a large mass.

[0003] The pressure and flow dual proportional valve can provide the necessary minimum pressure and flow for the actuator to work. Since the valve can control the pump pressure according to the load pressure and keep the pressure difference to the minimum, it is a low-energy, oil-inlet control throttling speed regulating valve. This valve has a temperature compensation function, which can make the control flow stable and not affected by the oil temperature. When this type of valve is used on a vulcanizer, it is generally connected to the plate-type reversing valve through an integrated block, and then connected to the oil cylinder through the working oil port on the integrated block. This installation method makes the oil path between the valves longer, affecting the system response speed. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a vulcanizer plate-type hydraulic valve group. The vulcanizer plate-type hydraulic valve group using the pressure and flow dual proportional valve eliminates the complex and large integrated block, which not only greatly shortens the oil circuit, but also further reduces the manufacturing cost.

[0005] The technical solution adopted by the present invention is: a vulcanizing machine plate-type hydraulic valve group, including a pressure and flow dual proportional valve and a plate-type valve group, the plate-type valve group is arranged on both sides of the valve body of the pressure and flow dual proportional valve, the valve body of the pressure and flow dual proportional valve is provided with an oil inlet, a total oil return port, a first working oil port, and a second working oil port, the first working oil port is provided with a corresponding first oil return port, an equal-difference overflow valve and a proportional throttle valve are arranged in the valve body, and the equal-difference overflow valve and the proportional throttle valve inlet are arranged in parallel, and the feature is that: an inlet check valve, an electromagnetic ball valve and a protective check valve are also arranged in the valve body; The inlet check valve is arranged before the inlet of the differential relief valve and the proportional throttle valve; The electromagnetic ball valve is arranged before the first working oil port; The protective one-way valve is arranged between the first working oil port, the second working oil port and the inlet of the equal differential relief valve, and its direction is from the first working oil port, the second working oil port to the inlet one-way valve.

[0006] Further, the plate-type valve group includes a first plate-type valve group and a second plate-type valve group respectively arranged on both sides of the pressure and flow dual proportional valve, wherein the first plate-type valve group includes a first plate-type valve and a second plate-type valve, the second plate-type valve group includes a third plate-type valve, a fourth plate-type valve, a fifth plate-type valve, and a sixth plate-type valve, a transition block is arranged between the pressure and flow dual proportional valve and the first plate-type valve, a first cartridge block is installed on the transition block, a first counter-valve matching the first plate-type valve is arranged on the first cartridge block, a second cartridge block is arranged on the side of the second plate-type valve facing away from the pressure and flow dual proportional valve, a second electromagnetic ball valve and a second one-way valve matching the second plate-type valve are arranged on the second cartridge block; a third cartridge block is arranged between the fourth plate-type valve and the fifth plate-type valve, a third counter-valve matching the fourth plate-type valve is inserted on the third cartridge block, a fourth cartridge block is arranged on the side of the sixth plate-type valve facing away from the pressure and flow dual proportional valve, and a fourth electromagnetic ball valve is arranged on the fourth cartridge block.

[0007] Further, the transition block is provided with an oil passage connecting the second working oil port and the first plate-type valve, the transition block is installed with a first plug-in block, the first plug-in block is plugged with a first counter-balancing valve and is provided with a corresponding oil passage, one of the working oil ports of the first plate-type valve is opened on the surface corresponding to the transition block, the transition block is provided with an oil passage connecting the working oil port of the first plate-type valve corresponding to the transition block and the inlet of the first counter-balancing valve and an oil passage connecting the outlet of the first counter-balancing valve, wherein the oil passage connecting the outlet of the first counter-balancing valve serves as the working oil port of the first plate-type valve. Furthermore, a first process hole is opened on the upper end face of the valve body, and the first process hole on the upper end face is connected to the valve hole where the differential relief valve is located, so that it is connected to the rear end pilot port of the differential relief valve. A first process hole is opened on the front end face of the valve body, and the first process hole on the front end face is connected to the first process hole on the upper end face. A first process hole is opened on the left end face of the valve body, and the first process hole on the left end face is connected to the oil outlet passage section of the valve hole where the proportional throttle valve is located and the first process hole on the front end face in sequence. Through the above arrangement, the outlet of the proportional throttle valve is connected to the rear end pilot port of the differential relief valve.

[0008] Further, the oil inlet is arranged on the lower end surface of the valve body, the first working oil port and the first oil return port are arranged on the left end surface of the valve body, and the second working oil port and the total oil return port are arranged on the right end surface of the valve body; The inlet check valve and the proportional throttle valve are inserted into the valve hole on the upper end face of the valve body, wherein the valve hole where the proportional throttle valve is located penetrates the valve body to the lower end face, and the equal-difference relief valve is inserted into the valve hole on the rear end face of the valve body, and the valve hole penetrates the valve body to the front end face, and the valve hole where the equal-difference relief valve is located is located between the valve holes where the inlet check valve and the proportional throttle valve are located, and a right end face process hole is opened on the right end face of the valve body, and the right end face process hole is connected to the inlet check valve, the equal-difference relief valve, and the valve hole where the proportional throttle valve is located in sequence, so that the outlet of the inlet check valve, the inlet of the equal-difference relief valve, the front pilot port, and the inlet of the proportional throttle valve are connected to each other; The protective one-way valve is inserted into the valve hole whose front end face is located between the valve hole where the equal differential relief valve is located and the left end face; The first oil return port and the main oil return port are connected; A first process hole is opened on the lower end surface of the valve body to connect the valve hole where the differential relief valve is located and the oil passage corresponding to the total oil return port, so that the oil outlet of the differential relief valve is connected to the total oil return port; The rear end face of the valve body is located between the valve hole where the electromagnetic ball valve is located and the upper end face, and a first process hole is set on the rear end face. The first process hole on the rear end face is connected to the valve hole where the proportional throttle valve is located, so that it is connected to the outlet of the proportional throttle valve. The upper end face is opened with a third process hole on the upper end face, and the third process hole on the upper end face is connected with the first process hole on the rear end face and the valve hole where the electromagnetic ball valve is located in sequence, so that it is connected to the inlet of the electromagnetic ball valve. Through the above arrangement, the outlet of the proportional throttle valve is connected to the inlet of the electromagnetic ball valve.

[0009] Furthermore, a first process hole is opened on the upper end face of the valve body, and the first process hole on the upper end face is connected to the valve hole where the differential overflow valve is located, so that it is connected to the rear end pilot port of the differential overflow valve. A first process hole is opened on the front end face of the valve body, and the first process hole on the front end face is connected to the first process hole on the upper end face. A first process hole is opened on the left end face of the valve body, and the first process hole on the left end face is connected to the oil outlet passage section of the valve hole where the proportional throttle valve is located and the first process hole on the front end face in sequence. Through the above arrangement, the outlet of the proportional throttle valve is connected to the rear end pilot port of the differential overflow valve.

[0010] Furthermore, the electromagnetic ball valve is inserted into a valve hole whose rear end face is located between the valve hole where the differential relief valve is located and the left end face, and the first working oil port is connected to the end of the valve hole where the electromagnetic ball valve is located, that is, the electromagnetic ball valve outlet.

[0011] Furthermore, the upper end surface of the valve body is provided with a second process hole on the upper end surface, which is sequentially connected with the first process hole on the left end surface and the end of the valve hole where the protective one-way valve is located. Through the above arrangement, the outlet of the proportional throttle valve is connected with the inlet of the protective one-way valve; The front end face of the valve body is provided with a second process hole, which is connected to the valve hole where the proportional throttle valve is located, so that it is connected to the inlet of the proportional throttle valve. The left end face of the valve body is provided with a third process hole on the left end face, which is connected to the valve hole where the protective one-way valve is located and the second process hole on the front end face in sequence. Through the above arrangement, the outlet of the protective one-way valve is connected to the inlet of the proportional throttle valve, and then connected to the inlet of the differential overflow valve.

[0012] Furthermore, it also includes a relief valve, the front end face of which is provided with an oil drain hole, the oil drain hole is connected to the oil outlet of the relief valve; the valve core of the equal differential relief valve is located on one side of the front end face and an overflow pipeline is additionally provided, the overflow pipeline connects the pilot port communication cavity at the rear end of the equal differential relief valve with the overflow oil inlet of the relief valve; One end of the proportional throttle valve close to the lower end face is a spring seat with a hole, and the outer end face of the spring seat is connected to the oil tank through a pipeline, so that the cavity where the spring seat is located is connected to the oil tank; The valve hole where the proportional throttle valve is located is close to the cavity where the spring seat is located at one end of the lower end face and is connected to the oil drain hole. The present invention improves the settings of the pressure and flow dual proportional valve and the disc valves on both sides thereof, and sets a plug-in block and a transition block between the dual proportional valve and the disc valve. Without increasing the original pressure and flow dual proportional valve body, the present invention shortens the oil circuit, adjusts the working oil port to the side of the valve body, and sets the pressure oil port on the bottom of the valve body, thereby achieving matching installation with the disc valve and greatly reducing the manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is the principle diagram of the present invention; Figure 2 This is the principle diagram of the pressure and flow dual proportional valve of the present invention; Figure 3 This is a first-view stereogram of the present invention; Figure 4 It is a stereoscopic diagram from a second viewing angle of the present invention; Figure 5 This is a first-view stereoscopic diagram of the pressure and flow dual proportional valve of the present invention; Figure 6 This is a stereoscopic diagram of the pressure and flow dual proportional valve of the present invention from a second viewing angle; Figure 7 This is a first-view stereoscopic view of the valve body of the pressure and flow dual proportional valve of the present invention; Figure 8 This is a second perspective stereoscopic view of the valve body of the pressure and flow dual proportional valve of the present invention; Fig. 9 It is a front projection view of the valve body of the pressure and flow dual proportional valve of the present invention; Fig.10 For the present invention Fig. 9 Middle AA section; Fig.11 For the present invention Fig. 9 Middle BB section; Fig.12 For the present invention Fig. 9 Middle CC section; Fig.13 It is a positive projection view of the left end face of the valve body of the pressure and flow dual proportional valve of the present invention; Fig.14 For the present invention Fig.13 Middle DD section; Fig.15 For the present invention Fig.13 Middle EE section; Fig.16 It is a right end face orthographic projection view of the pressure and flow dual proportional valve of the present invention; Fig.17 For the present invention Fig.16 Middle FF section; Fig.18 It is a front projection view of the rear end face of the pressure and flow dual proportional valve of the present invention; Fig.19 For the present invention Fig.18 Middle GG section; Fig. 20 It is a front projection view of the pressure and flow dual proportional valve of the present invention; Fig.21 For the present invention Fig. 20 Middle HH section; Fig. 22 For the present invention Fig. 20 Middle II section; Fig.23 It is a six-sided unfolded view of the valve body of the first piece valve of the present invention; Fig.24 This is a six-sided unfolded view of the valve body of the second piece valve of the present invention; Fig.25 It is a six-sided unfolded view of the transition block of the present invention; Fig.26 This is a six-sided unfolded view of the first plug-in block of the present invention; Fig. 27 This is a six-sided unfolded view of the fourth disc valve of the present invention; Fig.28 This is a six-sided unfolded view of the sixth disc valve of the present invention; Fig.29 This is a six-sided unfolded view of the second plug-in block of the present invention; Fig.30 This is a six-sided unfolded view of the third plug-in block of the present invention; Fig.31 This is a six-sided unfolded view of the fourth plug-in block of the present invention; Fig.32 It is a six-sided unfolded view of the third and fifth piece valves of the present invention.

[0014] In the figure: 1-pressure and flow dual proportional valve, 11-inlet check valve, 12-proportional throttle valve, 121-spring seat, 13-equal-difference overflow valve, 131-overflow pipeline, 14-proportional overflow valve, 141-damping hole, 15-solenoid ball valve, 16-protection check valve, 17-safety valve, 101-oil inlet, 102-first working oil port, 103-first oil return port, 104-second working oil port, 105-total oil return port, 201-oil inlet channel, 202-first working oil channel, 203-first oil return channel, 204-second working oil channel, 205-total oil return channel, 301-inlet check valve mounting hole, 302-throttle valve mounting hole, 303-equal-difference overflow valve mounting hole, 304-drain hole , 305- electromagnetic ball valve installation hole, 306- protection check valve installation hole, 411- front end face first process hole, 412- front end face second process hole, 421- rear end face first process hole, 422- rear end face second process hole, 431- left end face first process hole, 432- left end face second process hole, 433- left end face third process hole, 441- right end face process hole, 451- upper end face first process hole, 452- upper end face second process hole, 453- upper end face third process hole, 461- lower end face first process hole, 462- pressure measuring hole, 1001- front end face, 1002- rear end face, 1003- left end face, 1004- right end face, 1005- upper end face, 1006- lower end face; 10-first disc valve, 106-first oil inlet channel, 107-first oil return channel, 108-first front working oil port, 109-first upper working oil port, 110-first upper pilot port, 111-first lower working oil port; 2-second piece valve, 21-second cartridge block, 211-second cartridge oil inlet, 212-second solenoid ball valve cartridge hole, 213-second cartridge check valve cartridge hole, 214-second cartridge working oil port, 215-second cartridge oil return hole, 216-second cartridge process hole I, 217-second cartridge process hole II, 218-second cartridge process hole III, 219-quick oil return port; 22-second electromagnetic ball valve, 23-second cartridge check valve; 3- third piece valve; 4-the fourth plate valve, 41-the fourth oil inlet channel, 42-the fourth oil return channel, 43-the fourth left working oil port, 45-the fourth lower working oil port, 46-the fifth lower working oil port; 5-fifth disc valve, 51-third cartridge block, 52-third counterbalance valve, 511-third oil inlet channel, 512-third oil return channel, 513-third counterbalance valve installation hole, 514-third cartridge working oil port, 515-third cartridge process hole I, 516-third cartridge process hole II, 517-third cartridge oil inlet port, 518-third cartridge pilot port; 6-sixth disc valve, 61-fourth cartridge block, 611-fourth working oil inlet, 612-fourth solenoid ball valve cartridge hole, 613-fourth cartridge working oil port, 614-fourth cartridge return oil inlet, 615-fourth cartridge return oil outlet; 62- fourth electromagnetic ball valve; 7-transition block, 711-transition block counterbalance valve first interface, 712-transition block counterbalance valve second interface, 713-transition block third process hole, 714-transition block oil inlet connecting hole, 715-transition block first working oil port, 716-transition block second working oil port, 717-transition block oil return connecting hole, 718-transition block total oil return port, 719-transition block proportional oil return port, 710-transition block proportional oil inlet; 8-first plug-in block, 81-first counterbalance valve, 82-first counterbalance valve plug-in hole, 821-first plug-in working oil port, 83-first counterbalance valve control oil hole, 84-first plug-in oil inlet hole, 85-first plug-in process hole I, 86-first plug-in process hole II, 87-first plug-in process hole III. DETAILED DESCRIPTION

[0015] like Figure 1 As shown, a vulcanizing machine plate valve group includes a pressure and flow dual proportional valve 1, a first plate valve 10, a second plate valve 2, a third plate valve 3, a fourth plate valve 4, a fifth plate valve 5, and a sixth plate valve 6. The system pressure oil enters the oil inlet of each plate valve through the pressure and flow dual proportional valve 1. The first plate valve 10, the second plate valve 2, the fourth plate valve 4, and the sixth plate valve 6 are Y-type three-position four-way electromagnetic reversing valves, and the third plate valve 3 and the fifth solenoid valve 5 are O-type three-position four-way electromagnetic reversing valves. A first counterbalance valve 81 is provided at the working oil port of the first plate valve 10, and a second electromagnetic ball valve 22 and a second cartridge check valve 23 are provided at one of the working oil ports of the second plate valve 2, wherein the second cartridge check valve 23 is provided in the working oil circuit, and the second electromagnetic ball valve 22 is provided in the bypass oil circuit for draining the working oil circuit. The working oil port of the fourth plate valve 4 is provided with a third counterbalance valve 52 , and one working oil port of the sixth plate valve 6 is provided with a fourth electromagnetic ball valve 62 .

[0016] like Figure 1 , 3As shown in Figure 4, a vulcanizing machine plate-type hydraulic valve group includes a pressure and flow dual proportional valve 1, a first plate-type valve group and a second plate-type valve group, wherein the first plate-type valve group is a first plate-type valve 10 and a second plate-type valve 2 arranged below the pressure and flow dual proportional valve 1, and the second plate-type valve group includes a third plate-type valve 3, a fourth plate-type valve 4, a fifth plate-type valve 5, and a sixth plate-type valve 6 arranged above the pressure and flow dual proportional valve 1, a transition block 7 is arranged between the first plate-type valve 10 and the pressure and flow dual proportional valve 1, a first cartridge block 8 is installed on the transition block 7, a first counterbalance valve 81 is inserted on the first cartridge block 8, and a second cartridge block 21 is arranged on the side of the second plate-type valve 2 facing away from the pressure and flow dual proportional valve 1, and a second electromagnetic ball valve 22 and a second check valve 23 are inserted on the second cartridge block 21. The third plate valve 3 is adjacent to the pressure and flow dual proportional valve 1, and a third cartridge block 51 is arranged between the fourth plate valve 4 and the fifth plate valve 5, and a third counterbalance valve 52 is inserted on the third cartridge block 51. The sixth plate valve 6 is provided with a fourth cartridge block 61 on the side facing away from the pressure and flow dual proportional valve 1, and a fourth electromagnetic ball valve 62 and a fourth check valve 63 are arranged on the fourth cartridge block 61.

[0017] like Figure 2As shown, the pressure and flow dual proportional valve 1 includes an inlet check valve 11, a proportional throttle valve 12, an equal-difference relief valve 13, a proportional relief valve 14, an electromagnetic ball valve 15, a protection check valve 16, and a safety valve 17. The inlet check valve 11 is arranged at the oil inlet 101, and the outlet of the inlet check valve 11 is connected to the inlet of the proportional throttle valve 12, the inlet of the equal-difference relief valve 13, and the front pilot port. The outlet of the proportional throttle valve 12 is respectively connected to the first working oil port 102, the second working oil port 104, the rear end pilot port of the equal-difference relief valve 13, the inlet of the proportional relief valve 14, the inlet of the safety valve 17, and the inlet of the protection check valve 16, wherein the oil circuit between the outlet of the proportional throttle valve 12 and the rear end pilot port of the equal-difference relief valve 13, the inlet of the proportional relief valve 14, and the inlet of the safety valve 17 is provided with a damping hole 141, and the electromagnetic ball valve 15 is arranged between the outlet of the proportional throttle valve 12 and the first working oil port 102. The outlet of the equal-difference relief valve 13 is connected to the oil tank through the total oil return port 105, the first oil return port 103 is connected to the total oil return port 105, the internal drain port of the proportional throttle valve 12, the outlet of the proportional relief valve 14, and the outlet of the safety valve 17 are interconnected and return oil. The safety valve 17 adjusts the maximum working pressure of the working oil port to protect the overall hydraulic system. The proportional relief valve 14 adjusts the actual use pressure of the system according to the actual working conditions. The equal-difference relief valve 13 makes the pressure difference between the inlet and outlet of the proportional throttle valve 12 constant, so that the pressure of the oil inlet 101 changes with the load, instead of overflowing at the highest pressure, which plays an energy-saving role. Since the pressure difference between the inlet and outlet of the proportional throttle valve 12 is constant, dual precise proportional control of pressure and flow is achieved. When the working oil circuit where the first working oil port 102 and the second working oil port 104 are located has an instantaneous high pressure, the high-pressure oil can also be released by the equal-difference relief valve 13 through the protective check valve 16.

[0018] like Figure 5-22 As shown, a pressure and flow dual proportional valve includes a valve body 1, and the six end faces of the valve body 1 are respectively a front end face 1001, a rear end face 1002, a left end face 1003, a right end face 1004, an upper end face 1005, and a lower end face 1006.

[0019] The upper end surface 1005 is provided with an inlet check valve mounting hole 301 and a throttle valve mounting hole 302, and the throttle valve mounting hole 302 runs through the valve body 1 to the lower end surface; the lower end surface is provided with an oil inlet 101, and the oil inlet passage 201 corresponding to the oil inlet 101 is arranged opposite to and connected with the inlet check valve mounting hole 301; the front end surface is provided with a protective check valve mounting hole 306; the rear end surface is provided with an equal difference overflow valve mounting hole 303, an electromagnetic ball valve mounting hole 305, and an equal difference overflow valve mounting hole 306. The hole 303 passes through the valve body 1 to the front end face; a group of working oil ports are arranged on the left end face, namely the first working oil port 102 and the first oil return port 103, the first working oil port 102 and the first oil return port 103 correspond to the first working oil channel 202 and the first oil return channel 203 respectively; the second working oil port 104 and the total oil return port 105 are arranged on the right end face, the second working oil port 104 and the total oil return port 105 correspond to the second working oil channel 204 and the total oil return channel 205 respectively.

[0020] The front end face is provided with a first process hole 411, a second process hole 412, and an oil drain hole 304; the rear end face is provided with a first process hole 421, and a second process hole 422; the left end face is provided with a first process hole 431, a second process hole 432, and a third process hole 433; the right end face is provided with a right end face process hole 441, which is located between the second working oil port 104 and the total oil return port 105, and the process hole is connected to the inlet check valve mounting hole 301, the differential overflow valve mounting hole 303, and the throttle valve mounting hole 302 in sequence; the upper end face is provided with a first process hole 451, a second process hole 452, and a third process hole 453; the lower end face is provided with a first process hole 461 and a pressure measuring hole 462.

[0021] The differential relief valve installation hole 303 is located between the second working oil port 104 and the total oil return port 105. The differential relief valve installation hole 303 is provided with an annular cavity near the rear end face, and the annular cavity near the lower end face communicates with the total oil return passage 205. The lower end face process hole 461 communicates with the total oil return passage 205 and the annular cavity near the left end face of the differential relief valve installation hole 303 in sequence. The differential relief valve installation hole 303 is located on the front end face and communicates with the first process hole 451 on the upper end face.

[0022] The throttle valve installation hole 302 is provided with two groups of annular cavities, the annular cavity close to the upper end surface forms an oil inlet cavity, and the annular cavity close to the lower end surface forms an oil outlet cavity, the annular cavity close to the upper end surface is connected with the first process hole 431 of the left end surface, the first process hole 431 of the left end surface extends to the end and is connected with the first process hole 411 of the front end surface, and the first process hole 411 of the front end surface is connected with the first process hole 451 of the upper end surface. The cavity close to the lower end surface of the throttle valve installation hole 302 is connected with the second process hole 412 of the front end surface.

[0023] The third process hole 433 on the left end surface is connected with the protective one-way valve installation hole 306 and the second process hole 412 on the front end surface in sequence.

[0024] The second process hole 432 on the left end surface is connected to the second working oil channel 204 .

[0025] The second process hole 452 on the upper end surface is connected in sequence with the first process hole 431 on the left end surface and the end of the protective one-way valve installation hole 306 .

[0026] The third process hole 453 on the upper end surface is communicated with the electromagnetic ball valve installation hole 305 .

[0027] The first process hole 421 on the rear end surface is connected in sequence with the third process hole 453 on the upper end surface, the second process hole 432 on the left end surface, and the first process hole 431 on the left end surface.

[0028] The second process hole 422 on the rear end surface is connected to the main oil return passage 205 and the first oil return passage 203 in sequence.

[0029] An inlet check valve 11 is inserted into the inlet check valve mounting hole 301, a proportional throttle valve 12 is inserted into the throttle valve mounting hole 302, an asymmetric relief valve 13 is inserted into the asymmetric relief valve mounting hole 303, an electromagnetic ball valve 15 is provided in the electromagnetic ball valve mounting hole 305, and a protective check valve 16 is inserted into the protective check valve mounting hole 306.

[0030] The pressure oil of the pressure source enters the oil inlet passage 201 through the oil inlet port 101, enters the right end surface process hole 441 after passing through the inlet check valve 11, and then flows into the inlets of the proportional throttle valve 12 and the differential relief valve 13 respectively.

[0031] like Figure 5-22 As shown, in the proportional throttle valve 12, the pressure oil flows in from the annular cavity on the side of the throttle valve mounting hole 302 close to the lower end surface, and after being throttled by the valve core, flows out from the annular cavity on the side of the throttle valve mounting hole 302 close to the upper end surface, and the outflowing oil flows through the following paths respectively: Path 1: output from the first working oil port 102 through the first process hole 431 on the left end surface, the first process hole 421 on the rear end surface, the electromagnetic ball valve 15 , and the first working oil passage 202 .

[0032] Path 2: output from the second working oil port 104 through the first process hole 431 on the left end surface, the first process hole 421 on the rear end surface, the second process hole 432 on the left end surface, and the second working oil passage 204 .

[0033] Through path 1 and path 2, the working oil circuit is located on both sides of the valve body, so that it has the function of directly installing the plate valve group.

[0034] Path 3: It is connected to the inlet of the differential relief valve 13 through the first process hole 431 on the left end face, the second process hole 452 on the upper end face, the protective one-way valve 16, the third process hole 433 on the left end face, the second process hole 412 on the front end face, and the process hole 441 on the right end face.

[0035] Through path 3, when instantaneous high pressure occurs in the first working oil port 102 and the second working oil port 104, the high-pressure oil can overflow through the overflow valve in the working circuit itself, and can also overflow through path 3, through the protective one-way valve 16, and finally through the differential overflow valve 13, thereby achieving double protection for the entire working circuit.

[0036] Path 4: Enter the rear end pilot port communication cavity of the differential relief valve 13 through the first process hole 431 on the left end surface, the first process hole 411 on the front end surface, and the first process hole 451 on the upper end surface.

[0037] like Fig.17 As shown, one end of the proportional throttle valve 12 close to the lower end surface 1006 is a spring seat 121 with a hole, and the outer end surface of the spring seat is connected to the oil tank through a pipeline, so that the cavity where the spring seat is located is connected to the oil tank.

[0038] In the differential relief valve 13, the pressure oil enters the inlet of the differential relief valve mounting hole 303 and the front pilot port through the right end face process hole 441, and the overflow oil passes through the valve core of the differential relief valve 13, the annular cavity of the differential relief valve mounting hole 303, and the total return oil channel 205, and is finally discharged from the total return oil port 105.

[0039] Furthermore, the front end face 1001 is also equipped with a proportional overflow valve 14 and a safety valve 17. The valve body of the safety valve 17 is installed on the front end face 1001, and an overflow oil inlet and an oil outlet are provided on the interface between the valve body of the safety valve 17 and the front end face 1001. The proportional overflow valve 14 is connected to the overflow oil inlet and the oil outlet of the safety valve 17, and the internal oil circuit arrangement of the two is not the technical key point of this application, so it will not be repeated here.

[0040] The front end face 1001 is also provided with an oil drain hole 304, which is connected to the oil outlet of the safety valve 17, and the throttle valve mounting hole 302 is close to the cavity where the spring seat 121 is located at one end of the lower end face and is connected to the oil drain hole 304. Fig.18 , 19As shown, the valve core of the differential relief valve 13 is located on one side of the front end face and an overflow pipeline 131 is added. The overflow pipeline 131 connects the connecting cavity of the pilot port at the rear end of the differential relief valve 13 with the overflow oil inlet of the safety valve 17, thereby realizing the oil inlet of the proportional relief valve 14 and the safety valve 17. The first process hole 451 on the upper end face is connected. The damping hole 141 is arranged in the part between the first process hole 411 on the front end face and the mounting hole 303 of the differential relief valve, so that the oil throttled by the proportional throttle valve 12 enters the proportional relief valve 14, the safety valve 17 and the pilot port at the rear end of the differential relief valve 13 through the damping hole 141, thereby realizing the oil return of the proportional relief valve 14 and the safety valve 17.

[0041] The above valves and oil channels are connected to achieve Figure 2 Function of the schematic diagram.

[0042] like Fig.23 As shown, the first disc valve 10 adopts a standard 10-diameter disc valve body, with main valve core mounting holes on both sides, and a first oil inlet channel 106 and a first oil return channel 107 on the surface corresponding to the transition block 7, wherein the first oil inlet channel 106 passes through from the surface corresponding to the transition block 7 to the surface corresponding to the second disc valve 2, and the first oil return channel 107 is provided on the surface corresponding to the transition block 7 and is only connected to the main valve core mounting hole. The two working oil ports of the first disc valve 10 are the first front working oil port 108 and the first upper working oil port 109. Different from the standard 10-diameter disc valve body, the first upper working oil port 109 is not coplanar with the first front working oil port 108, but is provided on the surface corresponding to the first disc valve 10 and the transition block 7, and is connected to the oil channel of the transition block 7. The first disc valve 10 is also provided with a first upper pilot port 110 on the surface corresponding to the transition block 7, and the first upper pilot port 110 is connected to the first front working oil port 108. Compared with a standard valve body, the functions of the first upper working oil port 109 and the first upper pilot port 110 can be determined by the position of the internal connection to the main valve core mounting hole. Therefore, the internal communication structure is omitted in the present invention without affecting the integrity of the technical content.

[0043] like Fig.24 As shown, compared with the first plate valve 10, the first oil return channel 107 in the second plate valve 2 is only opened on the surface corresponding to the second cartridge block 21, and the original first upper working oil port 109 is changed to the first lower working oil port 111 corresponding to the surface of the second cartridge block 21, and its internal connection relationship is the same as that of the first upper working oil port 109.

[0044] like Fig.25As shown, the transition block 7 is used to input the pressure oil in the pressure and flow dual proportional valve 1 into the first plate valve 10, the second plate valve 2, and the return oil of the pressure and flow dual proportional valve 1 and the first plate valve 10. The openings on the transition block 7 include: a transition block proportional oil inlet 710 corresponding to the second working oil port 104, a transition block proportional oil return port 719 corresponding to the total oil return port 105, a transition block oil inlet connecting hole 714 corresponding to the first oil inlet channel 106 in the first plate valve 10, a transition block oil return connecting hole 717 corresponding to the first oil return channel 107 in the first plate valve 10, a transition block second working oil port 716 corresponding to the first upper working oil port 109, a transition block first working oil port 715 corresponding to the first upper pilot port 110, a transition block counterbalance valve first interface 711, a transition block counterbalance valve second interface 712, a transition block third process hole 713 opened on the side, and a transition block total oil return port 718 opened on the front end.

[0045] Among them, the first interface 711 of the transition block counterbalance valve is connected to the second working oil port 716 of the transition block, the second interface 712 of the transition block counterbalance valve is connected to the first working oil port 715 of the transition block, the third process hole 713 of the transition block is connected to the total oil return port 718 of the transition block and the proportional oil return port 719 of the transition block, the oil inlet connecting hole 714 of the transition block is connected to the proportional oil inlet 710 of the transition block, and the oil return connecting hole 717 of the transition block is connected to the total oil return port 718 of the transition block.

[0046] like Fig.26 As shown, the first counterbalance valve control oil hole 83, the first plug-in oil inlet hole 84, and the first plug-in process hole I 85 are provided at the upper end of the first plug-in block 8, and the first counterbalance valve plug-in hole 82 is opened at the right end. The first counterbalance valve plug-in hole 82 penetrates the first plug-in block 8 to its left end to form a first plug-in working oil port 821.

[0047] The first counterbalance valve 81 is a standard threaded cartridge counterbalance valve, the front section of the side thereof is a control oil port, the middle section is an oil inlet, and the rear section is an oil outlet.

[0048] The left end is provided with a first insertion process hole II 86, and the rear end is provided with a first insertion process hole III 87. Among them, the first insertion process hole I 85 is connected with the front end of the first counterbalance valve insertion hole 82, and the first insertion process hole II 86 is connected with the first counterbalance valve control oil hole 83 and the first insertion process hole I 85 in sequence, so that the first counterbalance valve control oil hole 83 is connected with the front end of the first counterbalance valve insertion hole 82, that is, the control oil port of the first counterbalance valve 81. The first insertion process hole III 87 is connected with the first insertion oil inlet hole 84 and the first counterbalance valve insertion hole 82 in sequence, so that the first insertion oil inlet hole 84 is connected with the middle section of the first counterbalance valve insertion hole 82, that is, the oil inlet of the first counterbalance valve 81. The surfaces where the first counterbalancing valve control oil hole 83 and the first plug-in oil inlet hole 84 are located correspond to the surfaces where the first interface 711 of the transition block counterbalancing valve and the second interface 712 of the transition block counterbalancing valve are located in the transition block 7. The first counterbalancing valve control oil hole 83 is connected to the first interface 711 of the transition block counterbalancing valve, and the first plug-in oil inlet hole 84 is connected to the second interface 712 of the transition block counterbalancing valve.

[0049] Through the above connection, the oil flowing out of the second working oil port 104 flows into the transition block 7 through the transition block proportional oil inlet port 710, flows out from the transition block oil inlet connecting hole 714, and enters the first oil inlet channel 106 of the first plate valve 10, the oil flowing out of the total oil return port 105 flows into the transition block 7 through the transition block proportional oil return port 719, and the oil flowing out of the first oil return channel 107 in the first plate valve 10 flows into the transition block 7 through the transition block oil return connecting hole 717. The oil flowing into the transition block proportional oil return port 719 returns to the transition block total oil return port 718 through the third process hole 713, and the oil flowing into the transition block oil return connecting hole 717 also returns to the transition block total oil return port 718.

[0050] There are two working oil paths flowing out of the main valve core of the first plate valve 10, one path flows out directly from the first front working oil port 108, and the other path flows through the first upper working oil port 109, the second working oil port 716 of the transition block, and the first interface 711 of the transition block counterbalance valve into the first plug-in block 8, and after passing through the counterbalance valve 81, it flows out from the first counterbalance valve plug-in hole 82 to the first plug-in working oil port 821 at the left end of the first plug-in block 8.

[0051] like Fig.32 As shown, the third plate valve 3 and the fifth plate valve 5 are standard 6-diameter plate valve bodies.

[0052] like Fig. 27As shown, the fourth plate-type valve 4 is modified from a standard 6-diameter plate-type valve body, and the channels include a main valve core hole, a fourth oil inlet channel 41, a fourth oil return channel 42, and a fourth left working oil port 43. The right working oil port is omitted. On the basis of the original channels, a fourth lower working oil port 45 and a fifth lower working oil port 46 are added. The fourth lower working oil port 45 is connected to the fourth left working oil port 43, and the fifth lower working oil port 46 is connected to the right working oil port connecting section of the main valve core hole on the fourth plate-type valve 4.

[0053] like Fig.28 As shown, compared with the fourth plate valve 4 , the sixth plate valve 6 lacks the fourth lower working oil port 45 .

[0054] like Fig.29 As shown, the second plug-in block 21 is provided with a second plug-in oil return hole 215 that passes through the upper and lower ends thereof. The second plug-in oil return hole 215 is located at the upper end side oil port and corresponds to the first oil return channel 107 in the second disc valve 2. The second plug-in oil return hole 215 is located at the lower end side oil port and returns oil through an external pipeline, thereby realizing the separate oil return of the second disc valve 2. The second plug-in oil inlet 211 is provided at the upper end of the second plug-in block 21, and the second plug-in oil inlet 211 corresponds to the first lower working oil port 111 in the second disc valve 2. The second electromagnetic ball valve plug-in hole 212 and the second plug-in check valve plug-in hole 213 are provided at the front end of the second plug-in block 21, and the second electromagnetic ball valve 22 and the second plug-in check valve 23 are plug-in respectively. The second plug-in oil inlet 211 is communicated with the end of the second plug-in check valve plug-in hole 213, thereby being connected to the oil inlet of the second plug-in check valve 23. A second plug-in working oil port 214 is set at the right end of the second plug-in block 21. The oil channel where the second plug-in working oil port 214 is located is connected to the second electromagnetic ball valve plug-in hole 212 and the middle section of the second plug-in check valve plug-in hole 213, so that the oil outlet of the second plug-in check valve 23 is connected to the second plug-in working oil port 214 and the oil port on one side of the second electromagnetic ball valve 22. A second insert process hole I216 is opened at the upper end of the second insert block 21, and the second insert process hole I216 is connected to the end of the second electromagnetic ball valve insert hole 212. A second insert process hole II217 is opened at the right end of the second insert block 21, and the second insert process hole II217 is connected to the second insert process hole I216. A quick oil return port 218 is opened at the lower end of the second insert block 21, and the oil channel where the quick oil return port 218 is located is connected to the second insert process hole II217, so that the oil port on the other side of the second electromagnetic ball valve 22 is connected to the quick oil return port 218 through the second insert process hole I216 and the second insert process hole II217.

[0055] Through the above connection, the second disc valve 2 returns oil separately through the second cartridge block 21, and the two working oil circuits of the second disc valve 2 are connected to the actuator through the first front working oil port 108 and the second cartridge working oil port 214 respectively, wherein the working oil circuit where the second cartridge working oil port 214 is located passes through the second cartridge one-way valve 23, and the oil outlet of the second cartridge one-way valve 23 corresponds to two oil circuits, one is the working oil circuit where the second cartridge working oil port 214 is located, and the other is the oil circuit passing through the second electromagnetic ball valve 22 and the quick oil return port 218, which is used for quick oil return of the actuator.

[0056] like Fig.30 As shown, the third plug-in block 51 is provided with a third oil inlet channel 511 and a third oil return channel 512, which are through holes at the upper and lower ends, ensuring that the oil inlet and oil return channels of the fourth plate valve 4 and the fifth plate valve 5 are connected, and the oil inlet and oil return ports of the plate valves on both sides are connected. The third counterbalance valve mounting hole 513 is provided at the rear end, and the third plug-in working oil port 514 is provided at the left end. The third plug-in oil inlet port 517 and the third plug-in pilot port 518 are provided at the bottom of the third plug-in block 51. The third plug-in oil inlet port 517 is connected to the fifth lower working oil port 46 of the fourth plate valve 4, and the third plug-in pilot port 518 is connected to the fourth lower working oil port 45 of the fourth plate valve 4.

[0057] The tail of the third counterbalance valve installation hole 513 is connected to the third plug-in working oil port 514. The third plug-in process hole I515 is set at the left end of the third plug-in block 51, and the third plug-in process hole I515 is connected to the third plug-in oil inlet 517 and the middle section of the third counterbalance valve installation hole 513, so that the oil flowing through the third plug-in working oil port 514 enters the oil inlet of the third counterbalance valve 52. The third plug-in process hole II516 is set at the right end of the third plug-in block 51, and the third plug-in process hole II516 is connected to the middle section of the third counterbalance valve installation hole 513 and the third plug-in pilot port 518, so that the oil flowing through the third plug-in pilot port 518 enters the pilot oil port of the third counterbalance valve 52.

[0058] By respectively connecting the fourth lower working oil port 45 and the fifth lower working oil port 46 of the fourth plate valve 4 to the oil inlet and the control oil port of the third counter-balancing valve 52, the oil outlet of the third counter-balancing valve 52 is connected to the third plug-in working oil port 514, so that the oil flowing through the fourth plate valve 4 is connected to the actuator through the fourth left working oil port 43 and the third plug-in working oil port 514.

[0059] like Fig.31As shown, the fourth plug-in block 61 is provided with a fourth working oil inlet 611 corresponding to the fifth lower working oil port 46 of the sixth disc valve 6, a fourth electromagnetic ball valve plug-in hole 612, and a fourth plug-in working oil port 613 is also provided on the front end surface, wherein the fourth working oil inlet 611 of the fifth lower working oil port 46 is communicated with the end of the fourth electromagnetic ball valve plug-in hole 612, and the fourth plug-in working oil port 613 is communicated with the middle section of the fourth electromagnetic ball valve plug-in hole 612. Through the above connection, the oil of the fifth lower working oil port 46 on the sixth disc valve 6 is introduced into the fourth plug-in block 61 through the fourth working oil inlet 611, and after passing through the fourth electromagnetic ball valve 62, it is discharged from the fourth plug-in working oil port 613, so that the oil flowing through the sixth disc valve 6 is communicated with the actuator through the fourth left working oil port 43 thereon and the fourth plug-in working oil port 613 on the fourth plug-in block 61. The fourth cartridge block 61 is also provided with a fourth cartridge oil return inlet 614 at the upper end, corresponding to the fourth oil return channel 42 in the sixth disc valve 6, and the fourth cartridge oil return outlet 615 is provided at the rear end of the fourth cartridge block 61, and the fourth cartridge oil return inlet 614 and the fourth cartridge oil return outlet 615 are connected. The return oil of the sixth disc valve 6 is returned separately through the fourth cartridge oil return inlet 614, the fourth cartridge oil return outlet 615 and the external pipeline.

[0060] The structures of each valve block in the present invention cannot be fully described, but the specific functional channel communications have been clearly stated, and the related designs are conventional designs in the field, so they are not displayed one by one, which does not affect the integrity of the technical content of the present invention.

[0061] The above structural features realize Figure 1 Function of the schematic diagram.

Claims

1. A vulcanizing machine plate-type hydraulic valve group, comprising a pressure and flow dual proportional valve and a plate-type valve group, characterized in that: The plate valve group is arranged on both sides of the valve body of the pressure and flow dual proportional valve. The valve body of the pressure and flow dual proportional valve is provided with an oil inlet (101), a total oil return port (105), a first working oil port (102), and a second working oil port (104). The first working oil port (102) is provided with a corresponding first oil return port (103). The valve body is provided with an equal-difference overflow valve (13) and a proportional throttle valve (12). The inlets of the equal-difference overflow valve (13) and the proportional throttle valve (12) are arranged in parallel. The valve body is characterized in that: an inlet check valve (11), an electromagnetic ball valve (15), and a protective check valve (16) are also provided in the valve body; The inlet check valve (11) is arranged before the inlets of the differential relief valve (13) and the proportional throttle valve (12); The electromagnetic ball valve (15) is arranged before the first working oil port (102); The protective one-way valve (16) is arranged between the first working oil port (102), the second working oil port (104) and the inlet of the differential relief valve (13), and its direction is from the first working oil port (102), the second working oil port (104) to the inlet one-way valve (11).

2. A vulcanizing machine plate type hydraulic valve group according to claim 1, characterized in that: The plate valve group includes a first plate valve group and a second plate valve group respectively arranged on both sides of the pressure and flow dual proportional valve, wherein the first plate valve group includes a first plate valve and a second plate valve, the second plate valve group includes a third plate valve, a fourth plate valve, a fifth plate valve, and a sixth plate valve, a transition block is arranged between the pressure and flow dual proportional valve and the first plate valve, a first cartridge block is installed on the transition block, a first counter-valve matching the first plate valve is arranged on the first cartridge block, a second cartridge block is arranged on the side of the second plate valve facing away from the pressure and flow dual proportional valve, a second electromagnetic ball valve and a second one-way valve matching the second plate valve are arranged on the second cartridge block; a third cartridge block is arranged between the fourth plate valve and the fifth plate valve, a third counter-valve matching the fourth plate valve is inserted on the third cartridge block, a fourth cartridge block is arranged on the side of the sixth plate valve facing away from the pressure and flow dual proportional valve, and a fourth electromagnetic ball valve is arranged on the fourth cartridge block.

3. A vulcanizing machine plate type hydraulic valve group according to claim 2, characterized in that: The transition block is provided with an oil passage connecting the second working oil port and the first plate-type valve, the transition block is installed with a first plug-in block, the first plug-in block is plugged with a first counter-balancing valve and is provided with a corresponding oil passage, one of the working oil ports of the first plate-type valve is opened on the surface corresponding to the transition block, the transition block is provided with an oil passage connecting the working oil port of the first plate-type valve corresponding to the transition block and the inlet of the first counter-balancing valve and an oil passage connecting the outlet of the first counter-balancing valve, wherein the oil passage connecting the outlet of the first counter-balancing valve serves as the working oil port of the first plate-type valve.

4. A vulcanizing machine plate type hydraulic valve group according to claim 2 or 3, characterized in that: The oil inlet (101) is arranged on the lower end surface of the valve body, the first working oil port (102) and the first oil return port (103) are arranged on the left end surface of the valve body, and the second working oil port (104) and the total oil return port (105) are arranged on the right end surface of the valve body; The inlet check valve (11) and the proportional throttle valve (12) are inserted into the valve hole on the upper end face of the valve body, wherein the valve hole where the proportional throttle valve (12) is located passes through the valve body to the lower end face, and the equal-difference relief valve (13) is inserted into the valve hole on the rear end face of the valve body, wherein the valve hole passes through the valve body to the front end face, and the valve hole where the equal-difference relief valve (13) is located is located between the valve holes where the inlet check valve (11) and the proportional throttle valve (12) are located, and a right end face process hole (441) is opened on the right end face of the valve body, and the right end face process hole (441) is connected to the valve holes where the inlet check valve (11), the equal-difference relief valve (13), and the proportional throttle valve (12) are located in sequence, so that the outlet of the inlet check valve, the inlet of the equal-difference relief valve, the front pilot port, and the inlet of the proportional throttle valve are connected to each other; The protective one-way valve (16) is inserted into a valve hole located at the front end face between the valve hole where the differential relief valve (13) is located and the left end face; The first oil return port (103) and the main oil return port (105) are connected; A first process hole (461) is formed on the lower end surface of the valve body, which is connected to the valve hole where the differential relief valve (13) is located and the oil passage corresponding to the total oil return port (105), so that the oil outlet of the differential relief valve (13) is connected to the total oil return port (105); The rear end face of the valve body is provided with a first process hole (421) on the rear end face between the valve hole where the electromagnetic ball valve (15) is located and the upper end face. The first process hole (421) on the rear end face is connected to the valve hole where the proportional throttle valve (12) is located, so that it is communicated with the outlet of the proportional throttle valve (12). The upper end face is provided with a third process hole (453) on the upper end face. The third process hole (453) on the upper end face is communicated with the first process hole (421) on the rear end face and the valve hole where the electromagnetic ball valve (15) is located in sequence, so that it is communicated with the inlet of the electromagnetic ball valve (15). Through the above arrangement, the outlet of the proportional throttle valve (12) is communicated with the inlet of the electromagnetic ball valve (15).

5. A vulcanizing machine plate type hydraulic valve group according to claim 2 or 3, characterized in that: The upper end surface of the valve body is provided with an upper end surface first process hole (451), which is connected to the valve hole where the differential relief valve (13) is located, so that it is connected to the rear end pilot port of the differential relief valve (13). The front end surface of the valve body is provided with a front end surface first process hole (411), which is connected to the upper end surface first process hole (451). The left end surface of the valve body is provided with a left end surface first process hole (431), which is connected in sequence to the oil outlet passage section of the valve hole where the proportional throttle valve (12) is located and the front end surface first process hole (411). Through the above arrangement, the outlet of the proportional throttle valve (12) is connected to the rear end pilot port of the differential relief valve (13).

6. A vulcanizing machine plate type hydraulic valve group according to claim 2 or 3, characterized in that: The electromagnetic ball valve (15) is inserted into a valve hole at the rear end face between the valve hole where the differential relief valve (13) is located and the left end face, and the first working oil port (102) is connected to the end of the valve hole where the electromagnetic ball valve (15) is located, that is, the outlet of the electromagnetic ball valve (15).

7. A vulcanizing machine plate type hydraulic valve group according to claim 2 or 3, characterized in that: The upper end surface of the valve body is provided with an upper end surface second process hole (452), and the upper end surface second process hole (452) is connected in sequence with the left end surface first process hole (431) and the end of the valve hole where the protective one-way valve (16) is located. Through the above arrangement, the outlet of the proportional throttle valve (12) is connected with the inlet of the protective one-way valve (16); The front end face of the valve body is provided with a second process hole (412) on the front end face, and the second process hole (412) on the front end face is connected to the valve hole where the proportional throttle valve (12) is located, so that it is connected to the inlet of the proportional throttle valve (12). The left end face of the valve body is provided with a third process hole (433) on the left end face, and the third process hole (433) on the left end face is connected to the valve hole where the protective check valve (16) is located and the second process hole (412) on the front end face in sequence. Through the above arrangement, the outlet of the protective check valve (16) is connected to the inlet of the proportional throttle valve (12), and further connected to the inlet of the differential relief valve (13).

8. A vulcanizing machine plate type hydraulic valve group according to claim 2 or 3, characterized in that: It also includes a relief valve, the front end face of which is provided with an oil drain hole (304), the oil drain hole (304) being connected to the oil outlet of the relief valve; the valve core of the differential relief valve (13) is located on one side of the front end face, and an overflow pipeline (131) is additionally provided, the overflow pipeline (131) connects the pilot port communication cavity at the rear end of the differential relief valve with the overflow oil inlet of the relief valve; One end of the proportional throttle valve (12) close to the lower end surface is a spring seat (121) with a hole, and the outer end surface of the spring seat is connected to the oil tank through a pipeline, so that the cavity where the spring seat (121) is located is connected to the oil tank; The cavity where the spring seat (121) is located at one end of the valve hole where the proportional throttle valve (12) is located near the lower end surface is communicated with the oil drain hole (304).

Images