Worm valve element assembly and hydraulic power-assisted steering system

Abstract

The utility model relates to the technical field of steering, and provides a worm valve element assembly and a hydraulic power-assisted steering system. The worm valve element assembly comprises a worm and a valve element arranged in the worm in a penetrating mode, first concave cavities are formed in the inner circumferential wall of the worm at intervals, second concave cavities are formed in the outer circumferential wall of the valve element at intervals, and when the valve element rotates, the second concave cavities communicate with the first concave cavities in the steering sides of the second concave cavities correspondingly to form high-pressure cavities and low-pressure cavities which are alternately distributed in the circumferential direction. The end edge of the first concave cavity and / or the end face of the second concave cavity are / is provided with cutting structures, and when the valve element rotates, pressure transition areas are formed between the high-pressure cavities and the adjacent low-pressure cavities based on the corresponding cutting structures. The cutting structure comprises a gap increasing structure acting on the overflowing gap of the pressure transition area and / or a length increasing structure acting on the overflowing length of the pressure transition area. The flow speed of hydraulic oil discharged from the high-pressure cavity to the low-pressure cavity is effectively reduced through the pressure transition area, and the purpose of reducing noise in the steering process is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of steering, in particular to a worm valve core component and a hydraulic steering assist system. Background Art

[0002] The hydraulic power steering system is equipped with a worm valve core assembly. Figure 1 As shown, the worm valve core assembly includes a worm 10 and a valve core 20 inserted into the worm 10. The inner peripheral wall of the worm 10 is provided with a first concave cavity 11, and the outer peripheral wall of the valve core 20 is provided with a second concave cavity 22. Figure 1 and Figure 2 As shown, when the steering wheel rotates counterclockwise, the valve core 20 rotates counterclockwise through a certain working angle, and each second cavity 22 is connected to the first cavity 11 on its steering side, that is, on its counterclockwise side, to form a circumferentially alternating high-pressure cavity 310 and low-pressure cavity 320; wherein the high-pressure cavity 310 is the oil inlet cavity and the low-pressure cavity 320 is the oil return cavity. Figure 1 and Figure 3 As shown, when the steering wheel rotates clockwise, the valve core 20 rotates clockwise through a certain working angle, and each second concave cavity 22 is respectively connected to its steering side, that is, the first concave cavity 11 on its clockwise side, to form a circumferentially alternating high-pressure cavity 310 and a low-pressure cavity 320.

[0003] When the steering wheel has no steering force, that is, the valve core 20 is in Figure 1 In the middle position shown, each second cavity 22 is also connected to the adjacent first cavity 11 via a gap, but no high or low pressure cavity is formed.

[0004] Figure 4 The negative pressure area and vortex formed by the worm valve core assembly are shown in figure. Figures 1 to 4 As shown, the problem with the worm valve core assembly is that during the steering process, the hydraulic oil in the high-pressure chamber 310 rapidly leaks to the low-pressure chamber 320, resulting in a negative pressure area near the oil outlet 330 ( Figure 4 The excessively low negative pressure causes air to separate out of the oil, i.e., cavitation occurs. The separated air is crushed by the high pressure, producing a gas explosion noise. In addition, the high flow rate causes a vortex to form near the oil outlet 330 (the position of the vortex is the same as that of the negative pressure area 330'), generating flow noise.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute prior art known to ordinary technicians in this field. Utility Model Content

[0006] In view of this, the utility model provides a worm valve core assembly and a hydraulic steering assist system, which forms a pressure transition zone that can increase the flow gap / extend the flow length by cutting the end edge of the first concave cavity and / or the end face of the second concave cavity. The pressure transition zone effectively reduces the flow rate of the hydraulic oil from the high-pressure chamber to the low-pressure chamber, thereby achieving the purpose of reducing noise during the steering process.

[0007] According to one aspect of the present invention, a worm valve core assembly is provided, comprising a worm and a valve core inserted in the worm, wherein first concave cavities are arranged at intervals on the inner peripheral wall of the worm, and second concave cavities are arranged at intervals on the outer peripheral wall of the valve core, and when the valve core rotates, each second concave cavity is respectively connected to the first concave cavity on its turning side to form a high-pressure cavity and a low-pressure cavity that are alternately distributed circumferentially; wherein a cutting structure is provided at the end edge of the first concave cavity and / or the end face of the second concave cavity, and when the valve core rotates, a pressure transition zone is formed between each high-pressure cavity and an adjacent low-pressure cavity based on the corresponding cutting structure, and the cutting structure includes a gap increasing structure acting on the flow gap of the pressure transition zone and / or a length extending structure acting on the flow length of the pressure transition zone.

[0008] In some embodiments, the cutting structure includes a gap increasing structure and a length extending structure arranged at the end edge of the first concave cavity, and the gap increasing structure and the length extending structure arranged at the end edge of the first concave cavity are formed by any one of the following structures: a chamfered surface, and the gap between the chamfered surface and the end face of the second concave cavity increases from the high-pressure cavity connected to the pressure transition zone to the low-pressure cavity; a wave surface, and the gap between the wave surface and the end face of the second concave cavity increases from the high-pressure cavity connected to the pressure transition zone to the low-pressure cavity; a step surface, and the gap between the step surface and the end face of the second concave cavity increases from the high-pressure cavity connected to the pressure transition zone to the low-pressure cavity.

[0009] In some embodiments, when the gap enlarging structure and the length extending structure provided at the end edge of the first cavity are formed by chamfered surfaces, the chamfered surfaces are rounded surfaces or chamfered beveled surfaces.

[0010] In some embodiments, when the chamfered surface is a beveled surface, a concave angle is further provided at one end of the beveled surface close to the high-pressure cavity connected to the pressure transition zone.

[0011] In some embodiments, the cutting structure includes a gap increasing structure and a length extending structure arranged on the end face of the second concave cavity, and the gap increasing structure and the length extending structure arranged on the end face of the second concave cavity are formed by a groove, and the gap between the groove and the end edge of the first concave cavity increases from the high-pressure cavity connected to the pressure transition zone to the low-pressure cavity.

[0012] In some embodiments, both ends of the groove close to the high-pressure chamber and the low-pressure chamber communicated with the pressure transition zone are respectively provided with chamfers.

[0013] In some embodiments, the cutting structure includes a length extension structure arranged at the end edge of the first concave cavity, and the length extension structure arranged at the end edge of the first concave cavity is formed by an extended cutting surface, and there is a uniform gap between the extended cutting surface and the end surface of the second concave cavity.

[0014] In some embodiments, when a cutting structure is provided at an end edge of the first concave cavity, a sidewall of the first concave cavity is provided with an inwardly contracted extension segment, and the cutting structure is provided at an end edge of the inwardly contracted extension segment.

[0015] According to another aspect of the present invention, a hydraulic power steering system is provided. The hydraulic power steering system is equipped with the worm valve core assembly as described in any of the above embodiments.

[0016] Compared with the prior art, the beneficial effects of the present invention include at least:

[0017] The utility model cuts the end edge of the first concave cavity of the worm and / or the end face of the second concave cavity of the valve core to form a pressure transition zone that connects the high-pressure cavity and the low-pressure cavity and can increase the flow gap / extend the flow length. The pressure transition zone effectively reduces the flow rate of the hydraulic oil leaking from the high-pressure cavity to the low-pressure cavity, avoids the risk of negative pressure and eddy current caused by sudden pressure changes, thereby effectively reducing the noise during the steering process and optimizing the performance of the worm valve core assembly and the hydraulic power steering system.

[0018] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory and are not restrictive of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0020] Figure 1 A schematic structural diagram of a worm valve core assembly is shown;

[0021] Figure 2 A schematic diagram showing the high-pressure chamber and low-pressure chamber formed by the worm valve core assembly when the valve core rotates counterclockwise;

[0022] Figure 3A schematic diagram showing the high-pressure chamber and low-pressure chamber formed by the worm valve core assembly when the valve core rotates clockwise;

[0023] Figure 4 A schematic diagram showing the negative pressure area and vortex formed by the existing worm valve core assembly;

[0024] Figure 5 A schematic diagram showing the cutting structure of the worm valve core assembly in an embodiment of the present utility model;

[0025] Figure 6 A schematic diagram showing a pressure transition zone formed by a worm valve core assembly in an embodiment of the present invention;

[0026] Figure 7 A schematic diagram showing a cutting structure in which a chamfered angled surface is provided at the end edge of the first concave cavity of the worm in an embodiment of the present invention;

[0027] Figure 8 A schematic diagram showing a cutting structure having a concave chamfered surface at the end edge of the first concave cavity of the worm in an embodiment of the present invention;

[0028] Figure 9 A schematic diagram showing a cutting structure with a wavy surface pattern provided at the end edge of the first concave cavity of the worm in an embodiment of the present invention;

[0029] Figure 10 A schematic diagram showing a cutting structure in which a stepped surface pattern is provided at the end edge of the first concave cavity of the worm in an embodiment of the present invention;

[0030] Figure 11 A schematic diagram showing a cutting structure in which a groove pattern is provided on the end surface of the second concave cavity of the valve core in an embodiment of the present utility model;

[0031] Figure 12 A schematic diagram showing an embodiment of the present invention in which cutting structures are provided on both the end edge of the first concave cavity of the worm and the end surface of the second concave cavity of the valve core;

[0032] Figure 13 A schematic diagram showing a cutting structure in which an extended cutting surface is provided at the end edge of the first concave cavity of the worm in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to make this disclosure more comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art.

[0034] The accompanying drawings are merely schematic illustrations of the present invention and are not necessarily drawn to scale. Identical reference numerals in the figures represent identical or similar structures, and thus their repeated descriptions will be omitted. The terms "first," "second," and similar terms used in the specific description do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Furthermore, in the description of the present invention, when a device is said to be "connected" to another device, this includes not only direct connections but also indirect connections through other elements.

[0035] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in different embodiments may be combined with each other.

[0036] Reference Figures 1 to 3 , and the above Figures 1 to 3 According to the description, the worm valve core assembly includes a worm 10 and a valve core 20 passing through the worm 10, the inner peripheral wall of the worm 10 is provided with a first concave cavity 11, and the outer peripheral wall of the valve core 20 is provided with a second concave cavity 22. When the valve core 20 rotates, each second concave cavity 22 is respectively connected with the first concave cavity 11 on its turning side, forming a high-pressure cavity 310 and a low-pressure cavity 320 that are alternately distributed circumferentially.

[0037] Figure 5 The cutting structure of the worm valve core assembly in the embodiment of the present utility model is shown in FIG. Figure 6 The pressure transition zone formed by the worm valve core assembly is shown in figure 2. Figures 1 to 3 、 Figure 5 and Figure 6 As shown, in the worm valve core assembly provided by the embodiment of the present utility model:

[0038] A cutting structure (110, 220) is provided at the end edge of the first concave cavity 11 and / or the end face of the second concave cavity 22. When the valve core 20 rotates, a pressure transition zone 360 ​​is formed between each high-pressure cavity 310 and the adjacent low-pressure cavity 320 based on the corresponding cutting structure. The cutting structure includes a gap increasing structure acting on the flow gap of the pressure transition zone 360 ​​and / or a length extending structure acting on the flow length of the pressure transition zone 360.

[0039] in, Figure 5 The diagram shows that if a cutting structure is provided on the worm 10, the cutting structure 110 is provided at the end edge of the first concave cavity 11; if a cutting structure is provided on the valve core 20, the cutting structure 220 is provided at the end surface of the second concave cavity 22. The cutting structure can be provided on both the worm 10 and the valve core 20, or on only one of them.

[0040] Figure 6The figure shows a possible structure of the pressure transition zone 360 ​​between the high-pressure chamber 310 and the adjacent low-pressure chamber 320. The pressure transition zone 360 ​​is formed by a cutting structure (specifically, an arcuate cut corner 110a) provided at the end edge of the first concave chamber 11 of the worm 10, which cooperates with the end surface of the second concave chamber 22 of the valve core 20. The arcuate cut corner 110a forms a chamfered surface at the end edge of the first concave chamber 11, which acts on the flow gap G of the pressure transition zone 360, making the flow gap G of the pressure transition zone 360 ​​smaller than that of the valve core 20. Figure 4 The pressure relief gap of the oil outlet 330 shown is effectively increased; at the same time, the chamfered angle surface formed by the arc cut corner 110a acts on the flow length L of the pressure transition zone 360, making the flow length L of the pressure transition zone 360 ​​relative to Figure 4 The pressure relief length of the oil outlet 330 shown is effectively extended. That is, in this embodiment, the curved cut corner 110a simultaneously creates a gap-enhancing structure and a length-extending structure. This creates a pressure transition zone 360 ​​that effectively reduces the flow rate of hydraulic oil from the high-pressure chamber 310 to the low-pressure chamber 320. Simulations have shown that the provision of the pressure transition zone 360 ​​significantly increases the negative pressure and reduces the vortex area 360', thereby reducing noise.

[0041] It should be noted that Figure 6 Only one feasible structure of the pressure transition zone 360 ​​is illustrated. In other embodiments, a corresponding pressure transition zone may be formed by cooperating other cutting structures provided at the end edge of the first concave cavity 11 of the worm 10 with the end surface of the second concave cavity 22 of the valve core 20, or by cooperating a cutting structure provided at the end surface of the second concave cavity 22 of the valve core 20 with the end edge of the first concave cavity 11 of the worm 10, or by cooperating a cutting structure provided at the end edge of the first concave cavity 11 of the worm 10 with a cutting structure provided at the end surface of the second concave cavity 22 of the valve core 20. In addition, the cutting structure may only include a gap increasing structure acting on the flow gap of the pressure transition zone 360, that is, the fitting gap between the end edge of the first concave cavity 11 of the worm 10 and the end face of the second concave cavity 22 of the valve core 20 is increased through the corresponding cutting structure; the cutting structure may only include a length extension structure acting on the flow length of the pressure transition zone 360, that is, the fitting length between the end edge of the first concave cavity 11 of the worm 10 and the end face of the second concave cavity 22 of the valve core 20 is extended through the corresponding cutting structure; the cutting structure may also include a gap increasing structure and a length extension structure at the same time to achieve a better noise reduction effect.

[0042] In summary, the utility model cuts the end edge of the first concave cavity 11 of the worm 10 and / or the end face of the second concave cavity 22 of the valve core 20 to form a pressure transition zone 360 ​​that connects the high-pressure cavity 310 and the low-pressure cavity 320 and can increase the flow gap G / extend the flow length L. The pressure transition zone 360 ​​effectively reduces the flow rate of the hydraulic oil leaking from the high-pressure cavity 310 to the low-pressure cavity 320, avoids the risk of negative pressure and eddy current caused by sudden pressure changes, thereby effectively reducing the noise during steering and optimizing the performance of the worm valve core assembly and the hydraulic steering power system.

[0043] In specific design, when the cutting structure includes a gap-enhancing structure, the ratio of the maximum to minimum flow gap formed by the gap-enhancing structure in the pressure transition zone 360 ​​is preferably less than 50. This effectively increases the flow gap in the pressure transition zone 360 ​​while preventing a large difference between the maximum and minimum flow gaps, which could cause a rapid change in the flow rate of the oil flowing through the pressure transition zone 360. When the cutting structure includes a length-extending structure, the flow length formed by the length-extending structure in the pressure transition zone 360 ​​can be 20% to 80% of the reference length (the distance from the starting point of the pressure transition zone 360 ​​to the oil return channel 12), and can be set as needed.

[0044] In some embodiments, the cutting structure includes a gap increasing structure and a length extending structure provided at the end edge of the first concave cavity 11 of the worm 10. The gap increasing structure and the length extending structure provided at the end edge of the first concave cavity 11 can be Figures 6 to 10 Any one of the cutting structures is formed.

[0045] Reference Figures 6 to 8 , and combined Figures 1 to 3 and Figure 5 As shown, the gap increasing structure and length extending structure arranged at the end edge of the first concave cavity 11 of the worm 10 can be a chamfered surface style cutting structure. The gap between the chamfered surface style cutting structure and the end face of the second concave cavity 22 of the valve core 20 increases from the high-pressure cavity 310 connected to the pressure transition zone 360 ​​to the low-pressure cavity 320. In this way, the chamfered surface style cutting structure is used to increase the flow gap G of the pressure transition zone 360 ​​and extend the flow length L of the pressure transition zone 360, thereby reducing the flow rate of the hydraulic oil leaking from the high-pressure cavity 310 to the low-pressure cavity 320, thereby achieving the purpose of reducing noise during the steering process.

[0046] Among them, the chamfered surface can be Figure 6 The rounded corner surface formed by the arc-shaped cut corner 110a shown in the figure can also be Figure 7The chamfered angled surface 110b is shown as a diagram. The radian, arc length and other parameters of the arc-shaped cut angle 110a can be set as needed; the radian can be constant or variable, as long as the gap between the chamfered angled surface and the end face of the second concave cavity 22 gradually increases from the high-pressure cavity 310 to the low-pressure cavity 320. The slope, length and other parameters of the chamfered angled surface 110b can be set as needed; the slope can be constant or variable, as long as the gap between the chamfered angled surface 110b and the end face of the second concave cavity 22 gradually increases from the high-pressure cavity 310 to the low-pressure cavity 320. Further, referring to Figure 8 As shown, a concave angle 110b' can also be provided at one end of the chamfered surface 110b close to the high-pressure chamber 310 connected to the pressure transition zone 360. The concave angle 110b' is used to reasonably increase the initial flow gap of the pressure transition zone 360 ​​to alleviate the pressure difference between the high-pressure chamber 310 and the low-pressure chamber 320.

[0047] Reference Figure 9 , and combined Figures 1 to 3 and Figure 5 As shown, the gap-enhancing and length-extending structures provided at the end edge of the first concave cavity 11 of the worm gear 10 can be a cutting structure in the form of a wave surface 110c. The gap between this cutting structure in the form of a wave surface 110c and the end surface of the second concave cavity 22 of the valve core 20 increases from the high-pressure cavity 310 connected to the pressure transition zone 360 ​​toward the low-pressure cavity 320. This cutting structure in the form of a wave surface 110c increases the flow gap G in the pressure transition zone 360 ​​and extends the flow length L in the pressure transition zone 360, thereby reducing the flow rate of hydraulic oil from the high-pressure cavity 310 to the low-pressure cavity 320 and achieving the purpose of reducing noise during the steering process. The corrugation parameters of the wave surface 110c can be set as needed, as long as the gap between the wave surface 110c and the end surface of the second concave cavity 22 gradually increases from the high-pressure cavity 310 connected to the pressure transition zone 360 ​​toward the low-pressure cavity 320.

[0048] Reference Figure 10 , and combined Figures 1 to 3 and Figure 5As shown, the gap-enhancing and length-extending structures provided at the end edge of the first concave cavity 11 of the worm 10 can be a cutting structure in the form of a stepped surface 110d. The gap between this stepped surface 110d and the end surface of the second concave cavity 22 of the valve core 20 increases from the high-pressure cavity 310 connected to the pressure transition zone 360 ​​toward the low-pressure cavity 320. This stepped surface 110d-like cutting structure increases the flow gap G in the pressure transition zone 360 ​​and extends the flow length L in the pressure transition zone 360, thereby reducing the flow rate of hydraulic oil from the high-pressure cavity 310 to the low-pressure cavity 320 and achieving the purpose of reducing noise during steering. The step parameters of the stepped surface 110d can be set as needed, as long as the gap between the stepped surface 110d and the end surface of the second concave cavity 22 gradually increases from the high-pressure cavity 310 connected to the pressure transition zone 360 ​​toward the low-pressure cavity 320.

[0049] Among them, the flow gap G of the pressure transition zone 360 ​​formed by the cutting structure in the wave surface 110c style and the cutting structure in the step surface 110d style increases discretely, and the flow gap G of the pressure transition zone 360 ​​formed by the cutting structure in the chamfered surface style increases continuously, both of which can achieve the purpose of reducing the flow rate of the hydraulic oil leaking from the high-pressure chamber 310 to the low-pressure chamber 320.

[0050] In some embodiments, the cutting structure includes a gap enlarging structure and a length extending structure provided on the end surface of the second concave cavity 22 of the valve core 20. Figure 11 , and combined Figures 1 to 3 and Figure 5 As shown, the gap-enhancing and length-extending structures provided on the end surface of the second concave cavity 22 of the valve core 20 are formed by a groove 220a. The gap between the groove 220a and the end edge of the first concave cavity 11 of the worm 10 increases from the high-pressure cavity 310 connected to the pressure transition zone 360 ​​toward the low-pressure cavity 320. This cutting structure, characterized by the groove 220a, increases the flow gap G in the pressure transition zone 360 ​​and extends the flow length L in the pressure transition zone 360, thereby reducing the flow rate of hydraulic oil flowing from the high-pressure cavity 310 to the low-pressure cavity 320 and achieving the purpose of reducing noise during steering. The depth, length, and other parameters of the groove 220a can be adjusted as needed, as long as the gap between the groove 220a and the end edge of the first concave cavity 11 gradually increases from the high-pressure cavity 310 connected to the pressure transition zone 360 ​​toward the low-pressure cavity 320.

[0051] Furthermore, in some embodiments, chamfers 220b are respectively provided at both ends of the high-pressure chamber 310 and the low-pressure chamber 320 connected to the pressure transition zone 360 ​​of the groove 220a. The chamfers 220b are used to buffer the flow rate of the oil entering and flowing out of the pressure transition zone 360 ​​and guide the flow direction of the oil to achieve better speed reduction and noise reduction effects.

[0052] Reference Figure 12 As shown, the worm 10 and the valve core 20 can be provided with cutting structures at the same time, wherein the cutting structure of the worm 10 is, for example, the arc-shaped cutting angle 110a described in the above embodiment, and the cutting structure of the valve core 20 is, for example, the groove 220a described in the above embodiment, so that the pressure transition zone 360 ​​formed has a better speed reduction and noise reduction effect.

[0053] Reference Figure 13 , and combined Figures 1 to 3 and Figure 5 As shown, in some embodiments, the cutting structure may simply include a length-extending structure in the form of an extended cutting surface 110e provided at the end edge of the first concave cavity 11 of the worm 10, with a uniform gap between the extended cutting surface 110e and the end surface of the second concave cavity 22 of the valve core 20. By extending the flow length L of the pressure transition zone 360 ​​through the cutting structure in the form of the extended cutting surface 110e, the flow rate of the hydraulic oil flowing from the high-pressure chamber 310 to the low-pressure chamber 320 can also be reduced, thereby reducing noise during the steering process.

[0054] In the above embodiments, referring to Figure 5 , and combined Figures 6 to 10 and Figure 12 and Figure 13 As shown, the cutting structure at the end edge of the first cavity 11 of the worm 10 can be achieved as follows: the sidewall of the first cavity 11 is provided with an inwardly extending section 100, and the cutting structure 110 is provided at the end edge of the inwardly extending section 100. In other words, compared to existing designs, when machining the worm 10 using the solution of the present invention, the width of the first cavity 11 can be appropriately reduced (from the original W1 to W1') to reserve the inwardly extending section 100 on the sidewall of the first cavity 11, and the corresponding cutting structure 110 is then machined at the end edge of the inwardly extending section 100.

[0055] The present invention also provides a hydraulic power steering system equipped with a worm gear valve core assembly as described in any of the above embodiments. Using the worm gear valve core assembly, by cutting the end edge of the first cavity 11 of the worm 10 and / or the end surface of the second cavity 22 of the valve core 20, a pressure transition zone 360 ​​is formed that connects the high-pressure chamber 310 and the low-pressure chamber 320 and increases the flow gap G / extends the flow length L. This effectively reduces the flow rate of hydraulic oil flowing from the high-pressure chamber 310 to the low-pressure chamber 320, reduces noise during steering, and optimizes the performance of the worm gear valve core assembly and the hydraulic power steering system.

[0056] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A worm valve core assembly, comprising a worm and a valve core inserted into the worm, wherein first concave cavities are spaced apart on the inner circumferential wall of the worm, and second concave cavities are spaced apart on the outer circumferential wall of the valve core. When the valve core rotates, each second concave cavity communicates with the first concave cavity on the side to which it turns, forming high-pressure and low-pressure cavities alternately distributed circumferentially. It is characterized by: A cutting structure is provided at the end edge of the first concave cavity and / or the end face of the second concave cavity. When the valve core rotates, a pressure transition zone is formed between each high-pressure chamber and the adjacent low-pressure chamber based on the corresponding cutting structure. The cutting structure includes a gap increasing structure acting on the flow gap of the pressure transition zone and / or a length extending structure acting on the flow length of the pressure transition zone.

2. The worm valve core assembly according to claim 1, characterized in that: The cutting structure includes a gap enlarging structure and a length extending structure provided at the end edge of the first concave cavity, wherein the gap enlarging structure and the length extending structure provided at the end edge of the first concave cavity are formed by any one of the following structures: a chamfered surface, wherein the gap between the chamfered surface and the end surface of the second concave cavity increases from the high-pressure cavity communicated with the pressure transition zone to the low-pressure cavity; a wave surface, wherein the gap between the wave surface and the end surface of the second concave cavity increases from the high-pressure cavity communicated with the pressure transition zone to the low-pressure cavity; A stepped surface is provided, and a gap between the stepped surface and the end surface of the second concave cavity increases from the high-pressure cavity communicated with the pressure transition zone to the low-pressure cavity.

3. The worm valve core assembly according to claim 2, characterized in that: When the gap enlarging structure and the length extending structure provided at the end edge of the first cavity are formed by chamfered surfaces, the chamfered surfaces are rounded surfaces or chamfered beveled surfaces.

4. The worm valve core assembly according to claim 3, characterized in that: When the chamfered surface is a chamfered angled surface, a concave angle is further provided at one end of the chamfered angled surface close to the high-pressure cavity communicated with the pressure transition zone.

5. The worm valve core assembly according to any one of claims 1 to 4, characterized in that: The cutting structure includes a gap increasing structure and a length extending structure arranged on the end face of the second concave cavity, and the gap increasing structure and the length extending structure arranged on the end face of the second concave cavity are formed by a groove, and the gap between the groove and the end edge of the first concave cavity increases from the high-pressure cavity connected to the pressure transition zone to the low-pressure cavity.

6. The worm valve core assembly according to claim 5, characterized in that: Both ends of the groove close to the high-pressure chamber and the low-pressure chamber communicated with the pressure transition zone are respectively provided with chamfers.

7. The worm valve core assembly according to claim 1, characterized in that: The cutting structure includes a length extension structure provided at the end edge of the first concave cavity, wherein the length extension structure provided at the end edge of the first concave cavity is formed by an extended cutting surface, and a uniform gap is provided between the extended cutting surface and the end surface of the second concave cavity.

8. The worm valve core assembly according to any one of claims 1 to 4 and 7, characterized in that: When the end edge of the first cavity is provided with a cutting structure: The side wall of the first cavity is provided with an inwardly contracted extension section, and the cutting structure is provided at the end edge of the inwardly contracted extension section.

9. A hydraulic power steering system, characterized in that: The hydraulic power steering system is equipped with a worm valve core assembly as described in any one of claims 1 to 8.

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