Hydraulic valve block for electric hydraulic tool

Abstract

The utility model provides a hydraulic valve block for an electric hydraulic tool, which comprises a large valve block and a small valve block, a plunger separating type length supplementing hole is arranged in the large valve block, the plunger separating type length supplementing hole is communicated with a plunger cavity in the small valve block, and a first oil inlet hole and a first oil outlet hole are communicated with the plunger cavity. The first oil outlet hole is communicated with a second oil inlet hole in the large valve block, the second oil inlet hole is respectively communicated with a second oil outlet hole and a second oil return hole in the large valve block, and the second oil return hole is communicated with the first oil return hole. Installation grooves are formed in the positions, between the first oil outlet hole and the second oil inlet hole and between the first oil return hole and the second oil return hole, between the small valve block and the large valve block in a matched mode, O-shaped rings are arranged in the installation grooves, and the installation grooves are provided with extrusion faces which enable the O-shaped rings to be limited and enable the O-shaped rings to be always sealed between the small valve block and the large valve block. According to the hydraulic valve block for the electric hydraulic tool, the oil leakage probability is greatly reduced, the production cost is reduced, the oil return efficiency is improved, the load of a motor is reduced, and the service life of the motor is prolonged.

Description

Technical Field

[0001] The utility model belongs to the technical field of hydraulic tools, and particularly relates to a hydraulic valve block for electric hydraulic tools. Background Art

[0002] Electric hydraulic tools usually include electric hydraulic pliers, hydraulic wrenches, hydraulic electric oil pumps, hydraulic jacks, hydraulic bolt tensioners, hydraulic hole openers, hydraulic flange separators, hydraulic nut cutters, hydraulic pullers and other split hydraulic tools.

[0003] Usually, all of the above electric hydraulic tools include a hydraulic valve block, and its working principle is to drive the eccentric mechanism to rotate through the motor, and then the eccentric mechanism drives the plunger rod to reciprocate, thereby converting the hydraulic oil from low pressure to high pressure. The pressure generated by the high-pressure oil provides driving power for hydraulic tools such as hydraulic pliers and hydraulic wrenches, thereby completing various tasks; when it is necessary to stop working, the motor stops working and the oil return valve starts working, so that the high-pressure oil returns to the chamber of low-pressure oil (usually an oil bag).

[0004] The existing hydraulic valve block has the following defects during long-term operation: 1. There are too many processing holes. The reason is that the design of the internal oil circuit of the existing hydraulic valve block is unreasonable, which leads to additional processing of transition holes on the hydraulic valve block in order to process the internal oil circuit, and then the holes involved in the internal oil circuit are processed through the transition holes, which increases the probability of oil leakage and increases the processing cost; 2. The hydraulic valve block is divided into a small valve block and a large valve block. The two are split designs, which requires sealing performance for the intersecting oil circuit positions after the two are assembled in place. The existing solution to achieve sealing performance is: a flat groove is opened on the small valve block at the position corresponding to the oil circuit, and an O-ring is placed in the flat groove to achieve a sealing effect. However, the O-ring is made of flexible material, the hydraulic oil in the oil circuit is ubiquitous, and flows in the oil circuit with a large pressure, and the O-ring is affected by the hydraulic Due to the flow force of oil, it is easy to be sucked into the oil hole, which makes the O-ring unable to ensure good sealing performance of the small valve block and the large valve block at the oil circuit connection position, which leads to oil leakage; 3. The connection design between the return oil valve and the return oil hole on the valve block is not reasonable. The reason is that the existing return oil valve is screwed into the return oil hole through the mounting seat, and a part of the mounting seat is in the return oil channel. At this time, when returning the oil, the high-pressure oil can only flow back to the low-pressure oil area through the threaded gap of the mounting seat, which leads to slow oil return and low efficiency; 4. In order to achieve the hydraulic driving force required by the market, the existing plunger outer diameter is usually designed to be 10mm, which puts a large load on the motor, resulting in the motor being unable to work for a long time and reducing the service life of the motor. In addition, this will directly bring about high temperature caused by the mechanical friction between the plunger and the eccentric wheel, which will cause the motor to fail to work normally. Summary of the invention

[0005] The utility model aims to solve the existing technical problem and provide a hydraulic valve block for electric hydraulic tools, the oil circuit design of which is more reasonable, thereby greatly reducing the generation of processing transition holes and reducing the probability of oil leakage; it re-optimizes the design of the flat groove, thereby making the O-ring more stable and having better sealing performance; it reduces the outer diameter of the plunger, while ensuring the hydraulic driving force, reducing the load of the motor and extending its service life.

[0006] The technical solution adopted by the utility model to solve the above technical problems is:

[0007] The utility model discloses a hydraulic valve block for an electric hydraulic tool, comprising a large valve block and a small valve block, wherein a plunger separation length auxiliary hole is provided in the large valve block, the plunger separation length auxiliary hole is communicated with a plunger cavity in the small valve block, and an oil inlet hole 1 and an oil outlet hole 1 are communicated with the plunger cavity, an oil inlet check valve and an oil outlet check valve are respectively provided at the positions of the oil inlet hole 1 and the oil outlet hole 1, the oil inlet hole 1 is communicated with an oil bag, the oil bag is installed on an oil bag seat of the small valve block, and the oil bag is communicated with an oil return hole 1 in the small valve block; the oil outlet hole 1 is communicated with an oil inlet hole 2 in the large valve block, the oil inlet hole 2 is respectively communicated with an oil outlet hole 2 and an oil return hole 2 in the large valve block, the oil return hole 2 is communicated with the oil return hole 1, and the The oil outlet hole 2 is connected with the external piston cavity, and an oil outlet check valve 2 is arranged between the oil outlet hole 2 and the oil inlet hole 2; the piston cavity is also connected with the oil return hole 2 through the oil return hole 3 on the large valve block, and a pressure regulating hole is provided at the intersection between the oil return hole 3 and the oil return hole 2, and a pressure regulating valve is arranged in the pressure regulating hole; an oil return valve hole is provided at a position between the oil inlet hole 2 and the oil return hole 2, and an oil return valve is arranged in the oil return valve hole; between the small valve block and the large valve block, an installation groove is provided at a position matching between the oil outlet hole 1 and the oil inlet hole 2, and between the oil return hole 1 and the oil return hole 2, and an O-ring is arranged in the installation groove, and the installation groove has an extrusion surface that limits the O-ring and always seals the O-ring between the small valve block and the large valve block.

[0008] The hydraulic valve block for electric hydraulic tools of the utility model adopts a reasonably designed hydraulic oil circuit to avoid machining more auxiliary holes on the surfaces of the large valve block and the small valve block, thereby greatly reducing the probability of oil leakage while reducing the machining cost; an O-ring is provided on the only connecting contact surface between the small valve block and the large valve block, and the O-ring is in a limited position formed by the extrusion surface design, thereby greatly improving the sealing performance and avoiding the occurrence of oil leakage.

[0009] The extrusion surface is a convex spherical surface, so that a conical annular groove is formed between the convex spherical surface and the side wall of the installation groove in the installation groove, and the O-ring is matched in the conical annular groove.

[0010] The distance from the intersection formed by the extrusion surface and the first oil outlet hole or the second oil inlet hole or the first oil return hole or the second oil return hole to the connecting contact surface of the large valve block and the small valve block is less than the cross-sectional diameter of the O-ring.

[0011] Due to the tight connection force between the large valve block and the small valve block, the O-ring is tightly squeezed in the conical annular groove. No matter how much MPa value of hydraulic oil is, it cannot affect the position and sealing performance of the O-ring. (The maximum hydraulic pressure value of the utility model can reach 100MPa, while the national standard hydraulic pressure value is 63MPa.)

[0012] The second oil inlet hole is connected to the second oil return hole through an oil return valve through hole. The oil return valve through hole is formed by drilling inwardly from the oil return valve hole. The second oil outlet hole is located at the position of the oil return valve through hole.

[0013] The oil return valve hole is a stepped hole, including a large diameter hole and a small diameter hole, the large diameter hole and the small diameter hole are concentric holes, and the two are designed to be axially connected front to back, the small diameter hole is respectively connected with the oil return hole 2 and the oil return valve through hole; the oil return valve includes a mounting seat, the center of the mounting seat is provided with a screw hole, a valve stem is threaded in the screw hole, a hand wheel is installed at the outer end of the valve stem, a valve core is provided at the inner end, a sealing ring is provided on the valve core, the sealing ring is sealed and connected with the valve core groove of the mounting seat, so as to prevent the hydraulic oil from leaking through the gap between the valve core and the valve core groove, the valve core is in the small diameter hole, and the valve core is directly against the steel ball placed in the small diameter hole; by rotating the hand wheel, the valve stem is driven to move forward and backward along the axial direction, so that the valve core has the effect of squeezing or loosening the steel ball, and then the through hole of the oil return valve and the oil return hole 2 are closed or connected.

[0014] The mounting seat of the oil return valve of the utility model is independently installed in the large-diameter hole, and the steel ball for blocking or opening is in the small-diameter hole, and the small-diameter hole is connected with the second oil return hole. In this way, when oil return is required, the hydraulic oil passes through the small-diameter hole and the second oil return hole at a full flow rate, thereby greatly improving the oil return efficiency.

[0015] The structure of the oil outlet check valve 1 is consistent with that of the oil outlet check valve 2, including a screw threaded in the oil outlet hole 1, a spring sleeved on the front end of the screw and a steel ball matched between the plunger cavity and the oil outlet hole 1. The spring has an elastic pressing effect on the steel ball, so that the steel ball can naturally block the oil outlet hole 1 to prevent the hydraulic oil in the plunger cavity from flowing back to the oil outlet hole 1.

[0016] The oil inlet one-way valve includes a screw seat screwed into an oil inlet hole and a steel ball movably embedded in a mounting groove at the inner end of the screw seat. The center of the screw seat has an oil hole that is connected to the mounting groove. The steel ball can perform one-way sealing on the oil hole.

[0017] The pressure regulating valve includes a set screw, a pressure regulating block and a spring connected between the set screw and the pressure regulating block. The front end of the pressure regulating block abuts against the steel ball. When the oil pressure in the hydraulic oil circuit is within a normal range, the steel ball blocks the position between the oil return hole three and the oil return hole two. When the oil pressure in the hydraulic oil circuit exceeds the normal range, the high oil pressure exceeds the elastic force given to the steel ball by the spring, thereby squeezing the spring, so that the high-pressure oil flows through the oil return hole three and the oil return hole two to the oil return hole one, and then flows back to the oil bag.

[0018] The large valve block is provided with a pressure gauge mounting hole, and the pressure gauge mounting hole is connected to the oil outlet hole.

[0019] The plunger installation space is composed of the plunger separation length auxiliary hole and the plunger cavity. A plunger assembly is arranged in the plunger installation space. The outer diameter of the plunger assembly is 8 mm.

[0020] The plunger assembly is driven by an eccentric wheel, and the eccentric radius and eccentric distance of the eccentric wheel are larger than those of the prior art, thereby increasing the driving stroke of the plunger assembly and then improving the driving force, so that the hydraulic valve block of the utility model provides a driving force that meets the requirements.

[0021] In summary, the beneficial effects of the utility model are:

[0022] Compared with the prior art, the hydraulic valve block for electric hydraulic tools of the utility model greatly reduces the probability of oil leakage and reduces the production cost. In addition, the hydraulic valve block for electric hydraulic tools of the utility model can improve the oil return efficiency, reduce the load of the motor, and extend its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional view of the utility model having a hydraulic valve block for an electric hydraulic tool;

[0024] Figure 2 yes Figure 1 A magnified view of part A;

[0025] Figure 3 yes Figure 1 A magnified view of part B;

[0026] Figure 4 yes Figure 1 Enlarged view of part C;

[0027] Figure 5 It is a three-dimensional diagram of a hydraulic valve block for an electric hydraulic tool of the utility model from one viewing angle;

[0028] Figure 6 It is a three-dimensional diagram of the hydraulic valve block for the electric hydraulic tool of the utility model from another perspective;

[0029] Figure 7 It is a three-dimensional cross-sectional view of a hydraulic valve block for an electric hydraulic tool of the utility model;

[0030] Figure 8 It is a structural schematic diagram of a pressure regulating valve of a hydraulic valve block for an electric hydraulic tool of the utility model;

[0031] Fig. 9 It is a structural schematic diagram of the oil inlet check valve of the hydraulic valve block for the electric hydraulic tool of the utility model;

[0032] Fig.10 It is a three-dimensional cross-sectional view of two positions of the oil outlet hole of the hydraulic valve block for the electric hydraulic tool of the utility model. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0034] See also Figures 1 to 10 The utility model provides a hydraulic valve block for an electric hydraulic tool, comprising a large valve block 1 and a small valve block 2. A plunger separation length auxiliary hole 3 is provided in the large valve block 1. This type of hole is used to solve the defect that a long connecting rod plunger assembly is easily broken due to high temperature caused by high-speed operation of a motor. The plunger separation length auxiliary hole 3 is connected to a plunger cavity 4 in the small valve block 2, and an oil inlet hole 5 and an oil outlet hole 6 are also connected to the plunger cavity 4; the oil inlet hole 5 is vertically connected to the plunger cavity 4, and the inner diameter of the oil inlet hole 5 is smaller than the inner diameter of the oil inlet check valve hole 7. The oil inlet check valve 47 is installed in the oil inlet check valve hole 7, which includes a screw seat 48 screwed in the oil inlet hole 5 and a steel ball 50 movably embedded in a mounting groove 49 at the inner end of the screw seat 48. The center of the screw seat 48 has an oil hole 51, and the oil hole 51 is connected to the mounting groove 49. The groove 49 is through-connected, and the steel ball 50 can perform one-way sealing on the oil hole 51; the oil outlet hole 16 includes an oil outlet hole 11 which is radially smaller than the outer diameter of the oil outlet one-way valve hole 46 along the plunger cavity 4, and an oil outlet hole 2 12 which is connected with the oil outlet one-way valve hole 46. Of course, the oil outlet one-way valve hole 46 and the oil outlet hole 11 here are concentric through holes, and the steel ball 9 of the oil outlet one-way valve 8 is blocked at the intersection of the oil outlet one-way valve hole 46 and the oil outlet hole 11 by the spring 10; the oil outlet one-way valve 8 also includes a screw 13 threadedly connected in the oil inlet hole 5 and the oil outlet hole 6, and the spring 10 is sleeved on the front end of the screw 13. The spring 10 has an elastic pressing effect on the steel ball 9 to prevent the hydraulic oil in the plunger cavity 4 from flowing back to the oil inlet hole 5 and the hydraulic oil in the oil outlet hole 6 from flowing back to the plunger cavity 4.

[0035] When the plunger assembly in the plunger chamber 4 reciprocates, the hydraulic oil in the oil bag (not shown in the figure) installed on the oil bag seat 14 of the small valve block 2 is sucked into the plunger chamber 4 through the oil inlet hole 15; the oil outlet hole 16 is connected with the oil inlet hole 2 15 in the large valve block 1, and the oil inlet hole 2 15 is respectively connected with the oil outlet hole 2 16 and the oil return hole 2 17 in the large valve block 1. During processing, we cannot process the oil inlet hole 2 15 to be connected with the oil outlet hole 2 16 and the oil return hole 2 17 in the large valve block 1 at one time, so we processed the return oil valve through hole 18. This return oil valve through hole 18 and the return oil valve hole 19 are concentric through holes, so that the oil inlet hole 2 15 is connected with the oil return hole 2 17. Therefore, the return oil valve through hole 18 is formed by drilling the return oil valve hole 19 inward, and the oil outlet hole 2 16 is connected at the position of the return oil valve through hole 18.

[0036] An oil outlet check valve 2 53 is provided between the oil outlet hole 2 16 and the oil inlet hole 2 15. The design of the oil outlet check valve 2 53 is to prevent the hydraulic oil flowing from the oil outlet hole 2 16 to the piston chamber from flowing back from the oil outlet hole 2 16 to the oil inlet hole 2 15, causing the flow direction of the hydraulic oil to be disturbed. We can open a mounting hole 54 on the large valve block 1. This mounting hole 54 passes through the oil inlet hole 2 15 and the oil outlet hole 2 16. The oil outlet check valve 2 53 has the same structure as the oil outlet check valve 1 8 and is screwed into the mounting hole 54.

[0037] The oil return valve hole 19 is located between the oil inlet hole 15 and the oil return hole 17, and is a stepped hole, including a large diameter hole 20 and a small diameter hole 21. The large diameter hole 20 and the small diameter hole 21 are concentric holes, and the two are axially through-designed. The small diameter hole 21 is respectively through-connected with the oil return hole 17 and the oil return valve through hole 18; an oil return valve 22 is installed in the oil return valve hole 19, including a mounting seat 23, a screw hole 24 is provided at the center of the mounting seat 23, a valve stem 25 is threadedly provided in the screw hole 24, a hand wheel 26 is installed at the outer end of the valve stem 25, a valve core 27 is provided at the inner end, and a sealing ring 28 is provided on the valve core 27, and the sealing ring 28 is sealed and docked with the valve core groove 29 of the mounting seat 23, so as to prevent the hydraulic oil from leaking through the gap between the valve core 27 and the valve core groove 29, and the valve core 27 is located in the small diameter hole 21, and the valve core 27 is directly against the steel ball 30 placed in the small diameter hole 21.

[0038] The mounting seat 23 of the oil return valve 22 of the utility model is independently installed in the large diameter hole 20, and the steel ball 30 for blocking or opening is located in the small diameter hole 21, and the small diameter hole 21 is connected with the second oil return hole 17. In this way, when oil return is required, the hydraulic oil passes through the small diameter hole 21 and the second oil return hole 17 in a full flow manner, thereby greatly improving the oil return efficiency.

[0039] The oil return hole 2 17 is connected with the oil return hole 1 31, the oil outlet hole 2 16 is connected with the external piston cavity, the piston cavity is connected with the oil return hole 2 17 through the oil return hole 3 32, and there is a pressure regulating hole 33 at the intersection between the oil return hole 3 32 and the oil return hole 2 17. How is the intersection formed here: we have added a pressure regulating oil return transition hole 34, so that the oil return hole 3 32 can be connected with both the oil return hole 2 17 and the oil inlet hole 2 15; a pressure regulating valve 35 is arranged in the pressure regulating hole 33. The pressure regulating oil return transition hole 24 is processed from the surface of the large valve block 1 inwardly. After the processing is completed, screws need to be installed in the pressure regulating oil return transition hole 24 to achieve the purpose of blocking and sealing.

[0040] Therefore, when the hydraulic oil pressure is too high or normal oil return is required, the high-pressure oil in the oil circuit will flow back to the low-pressure oil area (and eventually enter the oil bag) through the oil return hole 32 and the oil return hole 2 17, the piston chamber and the pressure regulating oil return transition hole 34, and the oil return hole 2 17.

[0041] Specifically, when normal oil return is required, the handwheel 26 of the oil return valve 22 is rotated to drive the valve stem 25 to move forward and backward along the axial direction, so that the valve core 27 has a squeezing or loosening effect on the steel ball 30, and then the oil return valve through hole 18 and the oil return hole 2 17 are connected, so that the high-pressure oil passes through the oil return hole 32, the oil return valve through hole 18, the small-diameter hole 21, the oil return hole 2 17, and the oil return hole 1 31 in sequence, and finally flows back to the oil bag (not shown in the figure); how to achieve the connection between the oil return hole 1 31 and the oil bag, here it is necessary to use the oil return transition hole 52, after the processing is in place, it is finally necessary to use screws to block the oil return transition hole 52; after the reflux is in place, the handwheel 26 of the oil return valve 22 is rotated in the opposite direction, so as to close the oil circuit between the oil return valve through hole 18 and the oil return hole 2 17, and prepare for the next work.

[0042] Specifically, the pressure regulating valve 35 includes a set screw 36, a pressure regulating block 37 and a spring 38 connected between the set screw 36 and the pressure regulating block 37. The front end of the pressure regulating block 37 abuts against the steel ball 39. When the oil pressure in the hydraulic oil circuit is within the normal range, the steel ball 39 blocks the position between the oil return hole 32 and the oil return hole 2 17. When the oil pressure in the hydraulic oil circuit exceeds the normal range, the high oil pressure exceeds the elastic force of the spring 38 given to the steel ball 39, thereby squeezing the spring 38, so that the high-pressure oil flows through the oil return hole 32 and the oil return hole 2 17 to the oil return hole 1 31, and then flows back to the oil bag (not shown in the figure).

[0043] The small valve block 2 is fixedly connected to the large valve block 1 by four bolts, and the hydraulic oil circulation position between the two is: oil outlet hole 16 and oil inlet hole 2 15, oil return hole 2 17 and oil return hole 1 31, so we provide a mounting groove 40 between the oil outlet hole 16 and oil inlet hole 2 15, oil return hole 1 31 and oil return hole 2 17, and an O-ring 41 is provided in the mounting groove 40, and the mounting groove has an extrusion surface 42 that limits the O-ring 41 and ensures that the O-ring 41 is always sealed between the small valve block 2 and the large valve block 1.

[0044] The extrusion surface 42 is a convex spherical surface, so that a conical annular groove 44 is formed between the convex spherical surface and the side wall 43 of the installation groove in the installation groove 40 , and the O-ring 41 is matched in the conical annular groove 44 .

[0045] The distance d from the intersection formed by the extrusion surface 42 and the oil outlet hole 16 or the oil inlet hole 2 15 or the oil return hole 1 31 or the oil return hole 2 17 to the connection contact surface of the large valve block 1 and the small valve block 2 is smaller than the cross-sectional diameter of the O-ring 41. In this way, the O-ring 41 is always in the conical annular groove 44, and will not be affected by the suction force generated by the flow of hydraulic oil, resulting in sealing failure.

[0046] Due to the tight connection force between the large valve block 1 and the small valve block 2, the O-ring 41 is tightly squeezed in the conical annular groove 44. No matter how much the MPa value of the hydraulic oil is, it cannot affect the position and sealing performance of the O-ring 41.

[0047] The large valve block 1 is provided with a pressure gauge mounting hole 45 , and the pressure gauge mounting hole 45 is connected with the second oil outlet hole 16 .

[0048] The plunger installation space is composed of the plunger separation length auxiliary hole 3 and the plunger cavity 4. A plunger assembly is arranged in the plunger installation space. The outer diameter of the plunger assembly is 8 mm. The plunger assembly is driven by an eccentric wheel. The eccentric radius of the eccentric wheel is larger than that of the prior art, thereby increasing the driving stroke of the plunger assembly and then improving the driving force, so that the hydraulic valve block of the utility model provides a driving force that meets the requirements.

[0049] The working principle of the hydraulic valve block for electric hydraulic tools of the utility model is explained below:

[0050] The hydraulic valve block for the electric hydraulic tool of the utility model has hydraulic oil stored in an oil bag (not shown in the figure). When it is necessary to increase the pressure to drive the piston chamber and then push the external working piece, the motor works to drive the eccentric wheel to rotate, and then drives the plunger to reciprocate along the axial direction, so that a pressure difference is formed in the plunger chamber 4, so that the hydraulic oil in the oil bag (not shown in the figure) is sucked into the plunger chamber 4 through the oil inlet hole 5, and the sucked hydraulic oil is squeezed by the plunger to push the oil outlet check valve 8 in the oil outlet hole 6. The steel ball 9 enters the oil outlet hole 6 in the form of high-pressure oil. During this process, since the oil inlet check valve 47 and the oil outlet check valve 8 are arranged in the oil inlet hole 5 and the oil outlet hole 6, the low-pressure oil can only enter the plunger chamber 4 from the oil bag (not shown in the figure), and the high-pressure oil can only enter the oil outlet hole 6 from the plunger chamber 4; then, the high-pressure oil reaches the oil return valve through hole 18 along the oil outlet hole 6 and the oil inlet hole 5, and then reaches the piston chamber along the oil outlet hole 2 16, thereby completing the boost drive work.

[0051] When it is necessary to stop working, the motor is turned off, and the handwheel 26 of the oil return valve 22 is rotated to drive the valve stem 25 to move forward and backward along the axial direction, so that the valve core 27 has the effect of squeezing or loosening the steel ball 30, and then the oil return valve through hole 18 and the oil return hole 2 17 are connected, so that the high-pressure oil passes through the oil return hole 3 32, the oil return valve through hole 18, the small-diameter hole 21, the oil return hole 2 17, and the oil return hole 1 31 in sequence, and finally flows back to the oil bag (not shown in the figure); after the reflux is in place, the handwheel 26 of the oil return valve 22 is rotated in the opposite direction, so as to close the oil circuit between the oil return valve through hole 18 and the oil return hole 2 17, so as to prepare for the next work.

[0052] In summary, the hydraulic valve block for electric hydraulic tools of the utility model adopts a reasonably designed hydraulic oil circuit to avoid processing more auxiliary holes on the surface of the large valve block 1 and the small valve block 2, thereby reducing the processing cost and greatly reducing the probability of oil leakage; an O-ring 41 is provided on the only connecting contact surface between the small valve block 2 and the large valve block 1, and the O-ring 41 is in the limited position formed by the design of the extrusion surface 42, thereby greatly improving the sealing performance and avoiding the occurrence of oil leakage.

[0053] The hydraulic valve block for electric hydraulic tools provided in the embodiment of the utility model is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the utility model. The description of the above embodiments is only used to help understand the technical solution disclosed by the utility model; at the same time, for general technicians in this field, according to the idea of ​​the utility model, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as a limitation of the utility model.

Claims

1. A hydraulic valve block for an electric hydraulic tool, comprising a large valve block and a small valve block, characterized in that: A plunger separation length auxiliary hole is provided in the large valve block, and the plunger separation length auxiliary hole is connected with the plunger cavity in the small valve block, and an oil inlet hole 1 and an oil outlet hole 1 are also connected with the plunger cavity, and an oil inlet check valve and an oil outlet check valve are respectively provided at the positions of the oil inlet hole 1 and the oil outlet hole 1, and the oil inlet hole 1 is connected with an oil bag, and the oil bag is installed on the oil bag seat of the small valve block, and the oil bag is connected with an oil return hole 1 in the small valve block; the oil outlet hole 1 is connected with the oil inlet hole 2 in the large valve block, and the oil inlet hole 2 is respectively connected with the oil outlet hole 2 and the oil return hole 2 in the large valve block, and the oil return hole 2 is connected with the oil return hole 1, and the oil outlet hole 2 is connected with the external piston cavity, and the oil outlet hole 1 is connected with the oil bag seat of the small valve block, and the oil bag is connected with the oil return hole 1. An oil outlet one-way valve No. 2 is provided between oil hole No. 2 and oil inlet hole No. 2; the piston chamber is also connected with oil return hole No. 2 through oil return hole No. 3 on the large valve block, and a pressure regulating hole is provided at the intersection between oil return hole No. 3 and oil return hole No. 2, and a pressure regulating valve is provided in the pressure regulating hole; an oil return valve hole is provided at a position between the oil inlet hole No. 2 and oil return hole No. 2, and an oil return valve is provided in the oil return valve hole; between the small valve block and the large valve block, an installation groove is provided at a position matching between the oil outlet hole No. 1 and the oil inlet hole No. 2, and between the oil return hole No. 1 and the oil return hole No. 2, and an O-ring is provided in the installation groove, and the installation groove has an extrusion surface that limits the O-ring and always seals the O-ring between the small valve block and the large valve block.

2. The hydraulic valve block for an electric hydraulic tool according to claim 1, characterized in that: The extrusion surface is a convex spherical surface, so that a conical annular groove is formed between the convex spherical surface and the side wall of the installation groove in the installation groove, and the O-ring is matched in the conical annular groove.

3. A hydraulic valve block for an electric hydraulic tool according to claim 1 or 2, characterized in that: The distance from the intersection formed by the extrusion surface and the first oil outlet hole or the second oil inlet hole or the first oil return hole or the second oil return hole to the connecting contact surface of the large valve block and the small valve block is less than the cross-sectional diameter of the O-ring.

4. The hydraulic valve block for an electric hydraulic tool according to claim 1, characterized in that: The second oil inlet hole is connected to the second oil return hole through an oil return valve through hole. The oil return valve through hole is formed by drilling inwardly from the oil return valve hole. The second oil outlet hole is located at the position of the oil return valve through hole.

5. A hydraulic valve block for an electric hydraulic tool according to claim 1 or 4, characterized in that: The oil return valve hole is a stepped hole, including a large diameter hole and a small diameter hole, the large diameter hole and the small diameter hole are concentric holes, and the two are designed to be axially connected front to back, the small diameter hole is respectively connected with the oil return hole 2 and the oil return valve through hole; the oil return valve includes a mounting seat, the center of the mounting seat is provided with a screw hole, a valve stem is threaded in the screw hole, a hand wheel is installed at the outer end of the valve stem, and a valve core is provided at the inner end, and a sealing ring is provided on the valve core, the sealing ring is sealed and docked with the valve core groove of the mounting seat, so as to prevent the hydraulic oil from leaking through the gap between the valve core and the valve core groove, the valve core is in the small diameter hole, and the valve core is directly against the steel ball placed in the small diameter hole; by rotating the hand wheel, the valve stem is driven to move forward and backward along the axial direction, so that the valve core has the effect of squeezing or loosening the steel ball, and then the through hole of the oil return valve and the oil return hole 2 are closed or connected.

6. The hydraulic valve block for an electric hydraulic tool according to claim 1, characterized in that: The structure of the oil outlet check valve 1 is consistent with that of the oil outlet check valve 2, including a screw threaded in the oil outlet hole 1, a spring sleeved on the front end of the screw and a steel ball matched between the plunger cavity and the oil outlet hole 1. The spring has an elastic pressing effect on the steel ball, so that the steel ball can naturally block the oil outlet hole 1 to prevent the hydraulic oil in the plunger cavity from flowing back to the oil outlet hole 1.

7. The hydraulic valve block for an electric hydraulic tool according to claim 1, characterized in that: The oil inlet one-way valve includes a screw seat screwed into an oil inlet hole and a steel ball movably embedded in a mounting groove at the inner end of the screw seat. The center of the screw seat has an oil hole that is connected to the mounting groove. The steel ball can perform one-way sealing on the oil hole.

8. The hydraulic valve block for an electric hydraulic tool according to claim 1, characterized in that: The pressure regulating valve includes a set screw, a pressure regulating block and a spring connected between the set screw and the pressure regulating block. The front end of the pressure regulating block abuts against the steel ball. When the oil pressure in the hydraulic oil circuit is within a normal range, the steel ball blocks the position between the oil return hole three and the oil return hole two. When the oil pressure in the hydraulic oil circuit exceeds the normal range, the high oil pressure exceeds the elastic force given to the steel ball by the spring, thereby squeezing the spring, so that the high-pressure oil flows through the oil return hole three and the oil return hole two to the oil return hole one, and then flows back to the oil bag.

9. The hydraulic valve block for an electric hydraulic tool according to claim 1, characterized in that: The large valve block is provided with a pressure gauge mounting hole, and the pressure gauge mounting hole is connected to the oil outlet hole.

10. The hydraulic valve block for an electric hydraulic tool according to claim 1, characterized in that: The plunger installation space is composed of the plunger separation length auxiliary hole and the plunger cavity. A plunger assembly is arranged in the plunger installation space. The outer diameter of the plunger assembly is 8 mm.

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