Economical hydraulic control multi-way reversing valve

Abstract

The economical hydraulic control multi-way reversing valve comprises a valve body, a rotating bucket valve rod assembly and a movable arm valve rod assembly, a traditional manual multi-way valve body blank is adopted as a valve body blank, the rotating bucket valve rod assembly comprises a rotating bucket valve rod, a rotating bucket end cover assembly and a right end cover, and the rotating bucket end cover assembly and the right end cover are arranged at the left end and the right end of the rotating bucket valve rod. The movable arm valve rod assembly comprises a movable arm valve rod, and a left end cover assembly and a right end cover assembly which are arranged at the left end and the right end of the movable arm valve rod. According to the manual multi-way reversing valve, the valve body and a traditional manual multi-way reversing valve body share the same blank, the cost of additional mold opening is saved, the structure is compact, the weight is light, installation is convenient, the manufacturing cost is greatly reduced, and the market competitiveness is improved; by arranging the rotating bucket end cover assembly, the left end cover assembly and the right end cover assembly, the functions and effectiveness of the economical hydraulic control multi-way reversing valve are consistent with those of an existing Karte hydraulic control multi-way reversing valve, so that the response speed and the control precision of the economical hydraulic control multi-way reversing valve are improved, and the economical hydraulic control multi-way reversing valve is stable and reliable.

Description

Technical Field

[0001] The utility model relates to the technical field of loader hydraulic systems, in particular to an economical hydraulically controlled multi-way reversing valve. Background Art

[0002] The operating conditions of the loader are mainly excavation and loading operations. In order to operate efficiently, the whole machine needs to frequently turn left and right, and the execution module needs to frequently retract the bucket, lift, unload, and lower, etc. The above actions are all controlled and realized by a hydraulically controlled multi-way reversing valve.

[0003] The Carter hydraulic multi-way reversing valve currently used on loaders is heavy and has high manufacturing costs, while the traditional manual multi-way reversing valve has slow response speed and low control accuracy when working. Therefore, it is urgent to design an economical hydraulic multi-way reversing valve, which is light in weight, easy to install, low in manufacturing cost, and strong in market competitiveness compared with the existing Carter hydraulic multi-way reversing valve; and has fast response speed, high control accuracy, and is stable and reliable compared with the traditional manual multi-way reversing valve. Utility Model Content

[0004] In order to solve the problems that the existing Carter hydraulically controlled multi-way valve is heavy and has high manufacturing cost, and the traditional manual multi-way valve has slow response speed and low control accuracy during operation, the utility model provides an economical hydraulically controlled multi-way directional valve, which adopts the traditional manual multi-way valve body blank, saves the cost of additional mold opening, greatly reduces manufacturing cost, and improves market competitiveness. By improving the structure of the bucket valve stem assembly and the boom valve stem assembly, the functional effectiveness of the economical hydraulically controlled multi-way directional valve is consistent with the existing Carter hydraulically controlled multi-way directional valve, thereby improving the response speed and control accuracy of the economical hydraulically controlled multi-way directional valve, which is stable and reliable.

[0005] To achieve the above-mentioned purpose, the utility model provides an economical hydraulically controlled multi-way reversing valve, comprising a valve body, a bucket valve stem assembly and a boom valve stem assembly, wherein the bucket valve stem assembly and the boom valve stem assembly are arranged in parallel at the middle upper part and the middle lower part of the valve body, and is characterized in that: the valve body blank adopts the traditional manual multi-way valve body blank, and the traditional manual multi-way valve body blank has a compact structure, light weight and convenient installation, the bucket valve stem assembly comprises a bucket valve stem, a bucket end cover assembly and a right end cover arranged at the left and right ends of the bucket valve stem, and the bucket end cover assembly is used for the rapid switching of the bucket between the bucket collection, the bucket tipping and the neutral action, the boom valve stem assembly comprises a boom valve stem, a left end cover assembly and a right end cover assembly arranged at the left and right ends of the boom valve stem, and the left end cover assembly and the right end cover assembly are used for the rapid switching of the boom between the lifting, lowering, neutral and floating actions, and a main safety valve is also provided on the valve body above the bucket valve stem assembly for adjusting the pressure of the hydraulically controlled multi-way reversing valve.

[0006] Preferably, an oil inlet is provided in the middle of the upper end of the valve body, a main oil inlet groove is provided below the oil inlet, a bucket collecting chamber, a first oil groove, a second oil groove, a third oil groove, a fourth oil groove, and a bucket tipping chamber are respectively provided in the valve body at positions corresponding to the bucket valve stem from left to right, the bucket collecting chamber is connected with the large chamber of the bucket oil cylinder, and the bucket tipping chamber is connected with the small chamber of the bucket oil cylinder, a boom lifting chamber, a fifth oil groove, a sixth oil groove, a seventh oil groove, and a boom lowering chamber are respectively provided in the valve body at positions corresponding to the boom valve stem from left to right, the boom lifting chamber is connected with the large chamber of the boom oil cylinder, and the boom lowering chamber is connected with the small chamber of the boom oil cylinder, an oil return groove is provided along the peripheral outer wall of the valve body, and when the bucket valve stem and the boom valve stem are in the middle position, the main oil inlet groove is connected with the second oil groove, the third oil groove, the sixth oil groove, and the seventh oil groove.

[0007] Preferably, the bucket end cover assembly includes a first end cover and a first screw rod, a first spring, a first spring seat, a second spring seat, a return spring, a first limiting washer and a first bolt arranged in the inner cavity of the first end cover, the first end cover is detachably and sealedly fixedly connected to the valve body, a first internal threaded hole is provided in the middle of the left end of the bucket valve stem, the right end of the first screw is threadedly connected to the first internal threaded hole, the first spring seat and the second spring seat are respectively sleeved on the outer sides of the left and right ends of the first screw rod, and both are connected to the first screw rod to form a linearly movable connection, a first expansion hole is provided on the right end surface of the first spring seat, and a first flange is provided on the left end, a second expansion hole is provided on the left end surface of the second spring seat, and a second flange is provided on the right end, the first spring is arranged in the first expansion hole and the second expansion hole, the return spring is sleeved on the outer sides of the first spring seat and the second spring seat, and the two ends are respectively fixedly connected to the first flange and the second flange, and the first limiting washer is tightened to the left end surface of the first screw rod and the first spring seat through the first bolt.

[0008] Preferably, the left end cover assembly includes a second end cover, an end sleeve and a second screw, a second spring, a third spring seat, a fourth spring seat, a second limiting washer and a second bolt arranged in the inner cavity of the end sleeve, the second end cover is detachably and sealingly fixedly connected to the left end face of the end sleeve, the end sleeve is detachably and sealingly fixedly connected to the valve body, a coaxial second internal threaded hole is provided in the middle of the left end of the boom valve stem, the right end of the second screw is threadedly connected to the second internal threaded hole, the third spring seat and the fourth spring seat are respectively sleeved on the outer sides of the left and right ends of the second screw, and both form a linearly movable connection with the second screw, the left end of the third spring seat is provided with a third flange, the right end of the fourth spring seat is provided with a fourth flange, the second spring is sleeved on the outer sides of the third spring seat and the fourth spring seat, and the two ends are fixedly connected to the third flange and the fourth flange respectively, the left end face of the third spring seat is provided with a third expanded hole, and the second limiting washer is tightened to the left end face of the second screw and the bottom surface of the third expanded hole through the second bolt.

[0009] Preferably, the right end cover assembly includes a third end cover and a third screw, a third spring, a fifth spring seat, a sixth spring seat, a third limiting washer and a third bolt arranged in the inner cavity of the third end cover, the third end cover is detachably and sealedly fixedly connected to the valve body, a coaxial third internal threaded hole is provided in the middle of the right end of the boom valve stem, the left end of the third screw is threadedly connected to the third internal threaded hole, the fifth spring seat and the sixth spring seat are respectively sleeved on the outer sides of the left and right ends of the third screw, and both form a linearly movable connection with the third screw, the left end of the fifth spring seat is provided with a fifth flange, and the right end of the sixth spring seat is provided with a sixth flange, the third spring is sleeved on the outer sides of the fifth spring seat and the sixth spring seat, and the two ends are fixedly connected to the fifth flange and the sixth flange respectively, and the third limiting washer is tightened to the left end surface of the third screw and the fifth spring seat through the third bolt.

[0010] Preferably, a plurality of evenly distributed annular pressure-equalizing grooves are provided on the first and second sections of the outer circumferential surface from the left, and the first and second sections of the outer circumferential surface from the right of the bucket valve stem.

[0011] Preferably, a plurality of annular pressure equalizing grooves are provided on the outer circumferential surfaces of the first, second, third, fourth and fifth sections of the boom valve stem from the left.

[0012] Preferably, the groove spacing of the annular pressure equalizing grooves is set to 3±0.1 mm.

[0013] Compared with the prior art, the beneficial effects of the utility model are:

[0014] 1. The utility model uses the same blank as the valve body of the traditional manual multi-way reversing valve, saving the cost of opening another mold. It has a compact structure, light weight, and is easy to install, which greatly reduces manufacturing costs and improves market competitiveness.

[0015] 2. The utility model makes the function of the economical hydraulically controlled multi-way reversing valve consistent with the existing Carter hydraulically controlled multi-way reversing valve by arranging the bucket end cover assembly, the left end cover assembly and the right end cover assembly, thereby improving the response speed and control accuracy of the economical hydraulically controlled multi-way reversing valve, and making it stable and reliable;

[0016] 3. The bucket valve stem and the boom valve stem of the utility model are improved on the basis of the corresponding valve stem of the manual multi-way reversing valve. By increasing the number of annular pressure-equalizing grooves on each outer circumferential surface of the bucket valve stem and the boom valve stem, the sticking phenomenon of the bucket valve stem and the boom valve stem is greatly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the structure of an embodiment of the utility model;

[0018] Figure 2 This is a schematic diagram of the structure of the bucket valve stem of the utility model embodiment;

[0019] Figure 3 This is a schematic diagram of the structure of the boom valve stem of an embodiment of the utility model;

[0020] Figure 4 This is a schematic diagram of the structure of the bucket end cover assembly of the utility model embodiment;

[0021] Figure 5 This is a schematic diagram of the structure of the left end cover assembly of an embodiment of the utility model;

[0022] Figure 6 This is a schematic diagram of the structure of the right end cover assembly of the utility model embodiment;

[0023] Figure 7 It is a schematic diagram of the structure of a traditional manual multi-way reversing valve;

[0024] Figure 8 This is a schematic diagram of the structure of the existing Carter hydraulically controlled multi-way directional valve.

[0025] In the figure: 1, valve body, 101, oil inlet, 102, main oil inlet groove, 103, bucket receiving chamber, 104, first oil groove, 105, second oil groove, 106, third oil groove, 107, fourth oil groove, 108, bucket tipping chamber, 109, boom lifting chamber, 110, fifth oil groove, 111, sixth oil groove, 112, seventh oil groove, 113, boom lowering chamber, 114, return oil groove, 2, main safety valve, 3, bucket valve stem, 301, first internal threaded hole, 302, equalizing pressure groove, 4, right end cover, 5, bucket end cover assembly, 501, first end cover, 502, first spring seat, 503, first spring, 504, second spring seat, 505, first screw, 506, Return spring, 507, first bolt, 508, first limiting washer, 6, boom valve stem, 601, second internal threaded hole, 602, pressure equalizing groove, 603, third internal threaded hole, 7, left end cover assembly, 701, second end cover, 702, end sleeve, 703, third spring seat, 704, second spring, 705, fourth spring seat, 706, second screw, 707, second bolt, 708, second limiting washer, 8, right end cover assembly, 801, third end cover, 802, fifth spring seat, 803, third spring, 804, sixth spring seat, 805, third screw, 806, third bolt, 807, third limiting washer, 3', bucket valve stem, 6', boom valve stem. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention.

[0028] like Figures 1 to 6 As shown, the embodiment of the utility model includes a valve body 1, a bucket valve stem assembly and a boom valve stem assembly, the bucket valve stem assembly and the boom valve stem assembly are arranged in parallel at the upper middle part and the lower middle part of the valve body 1, the valve body 1 blank adopts a traditional manual multi-way valve body blank, the traditional manual multi-way valve body blank has a compact structure, light weight, easy installation, and can greatly save manufacturing costs; the bucket valve stem assembly includes a bucket valve stem 3, a bucket end cover assembly 5 and a right end cover 4 arranged at the left and right ends of the bucket valve stem 3, the bucket end cover assembly 5 is used for the rapid switching between the bucket retracting, bucket tipping and neutral actions, the boom valve stem assembly includes a boom valve stem 6, a left end cover assembly 7 and a right end cover assembly 8 arranged at the left and right ends of the boom valve stem 6, the left end cover assembly 7 and the right end cover assembly 8 are used for the rapid switching of the boom between lifting, lowering, neutral and floating actions, and a main safety valve 2 is also provided on the valve body 1 above the bucket valve stem assembly for adjusting the pressure of the hydraulically controlled multi-way reversing valve.

[0029] In this embodiment, the valve body 1 is produced together with the valve body of a traditional manual multi-way reversing valve, which saves the cost of opening an additional mold. It has a compact structure, light weight, and is easy to install, which greatly reduces manufacturing costs and improves market competitiveness. By arranging the bucket end cover assembly 5, the left end cover assembly 7, and the right end cover assembly 8, the functional effectiveness of the economical hydraulically controlled multi-way reversing valve in this embodiment is consistent with the existing Carter hydraulically controlled multi-way reversing valve, thereby improving the response speed and control accuracy of the economical hydraulically controlled multi-way reversing valve, and being stable and reliable.

[0030] like Figure 1As shown, an oil inlet 101 is provided in the middle of the upper end of the valve body 1, and a main oil inlet groove 102 is provided below the oil inlet 101. A bucket collecting chamber 103, a first oil groove 104, a second oil groove 105, a third oil groove 106, a fourth oil groove 107, and a bucket tipping chamber 108 are provided in the valve body 1 at positions corresponding to the bucket valve stem 3 from left to right. The bucket collecting chamber 103 is connected to the large chamber of the bucket oil cylinder, and the bucket tipping chamber 108 is connected to the small chamber of the bucket oil cylinder. The corresponding positions in the valve body 1 and the boom valve stem 6 are provided from left to right. To the right, there are respectively provided a boom lifting chamber 109, a fifth oil groove 110, a sixth oil groove 111, a seventh oil groove 112 and a boom lowering chamber 113; the boom lifting chamber 109 is connected to the large chamber of the boom cylinder, the boom lowering chamber 113 is connected to the small chamber of the boom cylinder, and an oil return groove 114 is provided along the peripheral outer wall of the valve body 1; when the bucket valve stem 3 and the boom valve stem 6 are in the middle position, the main oil inlet groove 102 is connected to the second oil groove 105, the third oil groove 106, the sixth oil groove 111 and the seventh oil groove 112.

[0031] As a preference, Figure 4 As shown, the bucket end cover assembly 5 includes a first end cover 501 and a first screw 505, a first spring 503, a first spring seat 502, a second spring seat 504, a return spring 506, a first limit washer 508 and a first bolt 507 arranged in the inner cavity of the first end cover 501. The first end cover 501 is detachably sealed and fixedly connected to the valve body 1 through bolts and an O-ring. A first internal threaded hole 301 is provided in the middle of the left end of the bucket valve stem 3. The right end of the first screw 505 is threadedly connected to the first internal threaded hole 301. The first spring seat 502 and the second spring seat 504 are respectively sleeved on the first screw 5 05, and are both connected to the first screw rod 505 to form a linearly movable connection. The first spring seat 502 is provided with a first expansion hole on the right end face, and a first flange on the left end. The second spring seat 504 is provided with a second expansion hole on the left end face, and a second flange on the right end. The first spring 503 is arranged in the first expansion hole and the second expansion hole. The return spring 506 is sleeved on the outside of the first spring seat 502 and the second spring seat 504, and the two ends are fixedly connected to the first flange and the second flange respectively. The first limiting washer 508 is tightened to the first screw rod 505 and the left end face of the first spring seat 502 through the first bolt 507.

[0032] As a preference, Figure 5As shown, the left end cover assembly 7 includes a second end cover 701, an end sleeve 702 and a second screw 706, a second spring 704, a third spring seat 703, a fourth spring seat 705, a second limiting washer 708 and a second bolt 707 arranged in the inner cavity of the end sleeve 702. The second end cover 701 is detachably sealed and fixedly connected to the left end surface of the end sleeve 702 by bolts and an O-ring, and the end sleeve 702 is detachably sealed and fixedly connected to the valve body 1 by bolts and an O-ring. A coaxial second internal threaded hole 601 is provided in the middle of the left end of the boom valve stem 6, and the right end of the second screw 706 is threadedly connected to the second internal threaded hole 601. The third spring seat 703 and the fourth spring seat 705 are respectively sleeved on the outer sides of the left and right ends of the second screw rod 706, and both form a linearly movable connection with the second screw rod 706. The left end of the third spring seat 703 is provided with a third flange, and the right end of the fourth spring seat 705 is provided with a fourth flange. The second spring 704 is sleeved on the outer sides of the third spring seat 703 and the fourth spring seat 705, and the two ends are respectively fixedly connected to the third flange and the fourth flange. The left end face of the third spring seat 703 is provided with a third expanded hole, and the second limiting washer 708 is tightened to the left end face of the second screw rod 706 and the bottom face of the third expanded hole through the second bolt 707.

[0033] As a preference, Figure 6 As shown, the right end cover assembly 8 includes a third end cover 801 and a third screw 805, a third spring 803, a fifth spring seat 802, a sixth spring seat 804, a third limit washer 807 and a third bolt 806 arranged in the inner cavity of the third end cover 801. The third end cover 801 is detachably sealed and fixedly connected to the valve body 1 through bolts and O-rings. A coaxial third internal threaded hole 603 is provided in the middle of the right end of the boom valve stem 6. The left end of the third screw 805 is threadedly connected to the third internal threaded hole 603. The fifth spring seat 802, the sixth spring seat 804, the third limit washer 807 and the third bolt 806 are arranged in the inner cavity of the third end cover 801. The spring seats 804 are respectively sleeved on the outer sides of the left and right ends of the third screw rod 805, and both are connected to the third screw rod 805 to form a linearly movable connection. The left end of the fifth spring seat 802 is provided with a fifth flange, and the right end of the sixth spring seat 804 is provided with a sixth flange. The third spring 803 is sleeved on the outer sides of the fifth spring seat 802 and the sixth spring seat 804, and the two ends are fixedly connected to the fifth flange and the sixth flange respectively. The third limiting washer 807 is tightened to the third screw rod 805 and the right end surface of the fifth spring seat 802 through the third bolt 806.

[0034] As a preference, Figure 2 As shown, the first and second outer circumferential surfaces of the bucket valve stem 3 from the left are respectively provided with 6 and 10 evenly distributed annular pressure equalizing grooves 302, and the first and second outer circumferential surfaces from the right are respectively provided with 4 and 11 evenly distributed annular pressure equalizing grooves 302.

[0035] The number of the annular pressure equalizing grooves 302 on each outer circumferential surface is 1 to 2 more than the number of the annular pressure equalizing grooves at the corresponding positions on the rotary valve stem 3' of the conventional manual multi-way reversing valve.

[0036] As a preference, Figure 3 As shown, the first, second, third, fourth and fifth sections of the outer circular surface of the boom valve stem 6 from the left are respectively provided with 2, 11, 2, 3 and 4 evenly distributed annular pressure-equalizing grooves 602.

[0037] like Figure 7 As shown, the first section of the outer circumferential surface of the conventional manual multi-way reversing valve arm stem 6' has no annular pressure equalizing grooves, while the second, third, fourth and fifth sections of the outer circumferential surfaces are provided with 9, 1, 2 and 1 annular pressure equalizing grooves respectively.

[0038] The utility model greatly reduces the sticking phenomenon of the bucket valve stem 3 and the boom valve stem 6 by increasing the number of the annular pressure equalizing grooves 302 and 602 on the bucket valve stem 3 and the boom valve stem 6.

[0039] Preferably, the groove spacing between the annular pressure equalizing grooves 302, 602 is set to 3 mm.

[0040] Working principle of the utility model: when the bucket valve stem 3 and the boom valve stem 6 are in the middle position, the hydraulic oil directly enters from the oil inlet 101, flows along the main oil inlet groove 102, the second oil groove 105, the third oil groove 106, the sixth oil groove 111, and the seventh oil groove 112 directly into the oil return groove 114, and finally flows back to the oil tank;

[0041] When the bucket is turned and retracted, the bucket valve stem 3 moves to the right, the hydraulic oil flows from the first oil groove 104 to the bucket retracting chamber 103, the fourth oil groove 107 is closed, and the hydraulic oil in the bucket tipping chamber 108 flows into the return oil groove 114; when the bucket is turned and tipped, the bucket valve stem 3 moves to the left, the hydraulic oil flows from the fourth oil groove 107 to the bucket tipping chamber 108, the first oil groove 104 is closed, and the hydraulic oil in the bucket retracting chamber 103 flows into the return oil groove 114;

[0042] When the boom is raised, the boom valve stem 6 moves to the right, the sixth oil groove 111 and the seventh oil groove 112 are closed, the hydraulic oil flows from the fifth oil groove 110 to the boom lifting chamber 109, and the hydraulic oil in the boom lowering chamber 113 flows into the return oil groove 114; when the boom is lowered, the boom valve stem 6 moves to the left, the sixth oil groove 111 is closed, the hydraulic oil flows from the seventh oil groove 112 into the boom lowering chamber 113, and the hydraulic oil in the boom lifting chamber 109 flows into the return oil groove 114.

[0043] The above are only preferred implementations of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. An economical hydraulically controlled multi-way reversing valve, comprising a valve body, a bucket valve stem assembly and a boom valve stem assembly, wherein the bucket valve stem assembly and the boom valve stem assembly are arranged in parallel at the middle upper part and the middle lower part of the valve body, characterized in that: The bucket valve stem assembly includes a bucket valve stem, a bucket end cover assembly and a right end cover arranged at the left and right ends of the bucket valve stem, and the bucket end cover assembly is used for the rapid switching of the bucket between bucket collection, bucket tipping and neutral actions. The boom valve stem assembly includes a boom valve stem, a left end cover assembly and a right end cover assembly arranged at the left and right ends of the boom valve stem, and the left end cover assembly and the right end cover assembly are used for the rapid switching of the boom between lifting, lowering, neutral and floating actions. A main safety valve is also arranged on the valve body above the bucket valve stem assembly, which is used to adjust the pressure of the hydraulically controlled multi-way reversing valve; The valve body blank has a compact structure and light weight. An oil inlet is provided in the middle of the upper end of the valve body, and a main oil inlet groove is provided below the oil inlet. A bucket collecting chamber, a first oil groove, a second oil groove, a third oil groove, a fourth oil groove, and a bucket tipping chamber are respectively provided in the valve body at positions corresponding to the bucket valve stem from left to right. The bucket collecting chamber is connected with the large chamber of the bucket oil cylinder, and the bucket tipping chamber is connected with the small chamber of the bucket oil cylinder. A boom lifting chamber, a fifth oil groove, a sixth oil groove, a seventh oil groove, and a boom lowering chamber are respectively provided in the valve body at positions corresponding to the boom valve stem from left to right. The boom lifting chamber is connected with the large chamber of the boom oil cylinder, and the boom lowering chamber is connected with the small chamber of the boom oil cylinder. An oil return groove is provided along the peripheral outer wall of the valve body. When the bucket valve stem and the boom valve stem are in the middle position, the main oil inlet groove is connected with the second oil groove, the third oil groove, the sixth oil groove, and the seventh oil groove.

2. An economical hydraulically controlled multi-way directional control valve according to claim 1, characterized in that: The bucket end cover assembly includes a first end cover and a first screw rod, a first spring, a first spring seat, a second spring seat, a return spring, a first limiting washer and a first bolt arranged in the inner cavity of the first end cover, the first end cover is detachably and sealedly fixedly connected to the valve body, a first internal threaded hole is provided in the middle of the left end of the bucket valve stem, the right end of the first screw rod is threadedly connected to the first internal threaded hole, the first spring seat and the second spring seat are respectively sleeved on the outer sides of the left and right ends of the first screw rod, and both are connected to the first screw rod to form a linearly movable connection, a first expansion hole is provided on the right end surface of the first spring seat, and a first flange is provided on the left end, a second expansion hole is provided on the left end surface of the second spring seat, and a second flange is provided on the right end, the first spring is arranged in the first expansion hole and the second expansion hole, the return spring is sleeved on the outer sides of the first spring seat and the second spring seat, and the two ends are respectively fixedly connected to the first flange and the second flange, and the first limiting washer is tightened to the first screw rod and the left end surface of the first spring seat through the first bolt.

3. The economical hydraulically controlled multi-way directional control valve according to claim 1 is characterized in that: The left end cover assembly includes a second end cover, an end sleeve and a second screw, a second spring, a third spring seat, a fourth spring seat, a second limiting washer and a second bolt arranged in the inner cavity of the end sleeve. The second end cover is detachably and sealedly fixedly connected to the left end face of the end sleeve, and the end sleeve is detachably and sealedly fixedly connected to the valve body. A coaxial second internal threaded hole is provided in the middle of the left end of the boom valve stem, and the right end of the second screw is threadedly connected to the second internal threaded hole. The third spring seat and the fourth spring seat are respectively sleeved on the outer sides of the left and right ends of the second screw, and both form a linearly movable connection with the second screw. The left end of the third spring seat is provided with a third flange, and the right end of the fourth spring seat is provided with a fourth flange. The second spring is sleeved on the outer sides of the third spring seat and the fourth spring seat, and the two ends are fixedly connected to the third flange and the fourth flange respectively. A third reaming hole is provided on the left end face of the third spring seat, and the second limiting washer is tightened to the left end face of the second screw and the bottom surface of the third reaming hole through the second bolt.

4. The economical hydraulically controlled multi-way directional control valve according to claim 1, characterized in that: The right end cover assembly includes a third end cover and a third screw, a third spring, a fifth spring seat, a sixth spring seat, a third limiting washer and a third bolt arranged in the inner cavity of the third end cover. The third end cover is detachably and sealedly fixedly connected to the valve body. A coaxial third internal threaded hole is provided in the middle of the right end of the boom valve stem. The left end of the third screw is threadedly connected to the third internal threaded hole. The fifth spring seat and the sixth spring seat are respectively sleeved on the outer sides of the left and right ends of the third screw, and both form a linearly movable connection with the third screw. The left end of the fifth spring seat is provided with a fifth flange, and the right end of the sixth spring seat is provided with a sixth flange. The third spring is sleeved on the outer sides of the fifth spring seat and the sixth spring seat, and the two ends are fixedly connected to the fifth flange and the sixth flange respectively. The third limiting washer is tightened to the left end surface of the third screw and the fifth spring seat through the third bolt.

5. The economical hydraulically controlled multi-way directional control valve according to claim 1 is characterized in that: A plurality of evenly distributed annular pressure-equalizing grooves are provided on the first and second sections of the outer circular surface from the left and the first and second sections of the outer circular surface from the right of the bucket valve stem.

6. The economical hydraulically controlled multi-way directional control valve according to claim 1, characterized in that: The first, second, third, fourth and fifth outer circumferential surfaces of the boom valve stem from the left are each provided with a plurality of annular pressure equalizing grooves.

7. An economical hydraulically controlled multi-way directional control valve according to claim 5 or 6, characterized in that: The groove spacing of the annular pressure equalizing groove is set to 3±0.1 mm.

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