Variable structure and pump structure
By distributing oil holes and high-pressure flow channels on the swashplate, the problems of wear on the contact surface between the slipper and the swashplate and insufficient lubricating oil pressure are solved, achieving stable lubrication and reducing wear, thus extending the service life of the plunger pump.
Patent Information
- Application Number
- CN202520560150.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-27
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2035-03-27
AI Technical Summary
In existing plunger pumps, the contact surface between the slipper and the swashplate is severely worn, resulting in insufficient lubricating oil pressure. This leads to slipper failure and stamping marks on the working surface of the swashplate, affecting the pump's lifespan and performance.
At least four oil holes are distributed on the high-pressure side of the swashplate to keep the high-pressure chamber of the slipper connected to the oil holes, and high-pressure oil is introduced between the swashplate and the bearing through the high-pressure flow channel to maintain a stable lubrication effect.
By continuously supplying high-pressure oil, the stamping marks between the slipper and the swashplate are eliminated, wear is reduced, the service life of the slipper and swashplate is extended, and the lubrication effect and pump stability are improved.
Smart Images
Figure CN223724774U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of plunger pump, especially variable structure and pump structure. BACKGROUND
[0002] Plunger pump is an important component of hydraulic system. Plunger pump usually includes rotating shaft, swash plate, cylinder body and multiple plungers. The cylinder body has multiple plunger holes arranged circumferentially around the rotating axis, and the multiple plungers are assembled into the multiple plunger holes one by one. The swash plate includes a working surface inclined relative to the rotating axis, and the end of the multiple plungers protruding from the plunger holes is matched with the working surface of the swash plate through the sliding shoe. During operation, the multiple plungers rotate along with the cylinder body around the rotating shaft, and at the same time, the plungers longitudinally translate in the plunger holes to transfer pressure medium. The stroke of the plungers can be adjusted by adjusting the inclination angle of the swash plate.
[0003] In the structural design, the lubrication and static pressure support between the various parts of the plunger pump are important design links in the design of the axial plunger pump, among which, the lubrication of the variable swash plate and the bearing shell on the swash plate seat is particularly important. Figure 1 As shown in the figure, the existing plunger pump selects a small oil channel 11' on the high-pressure side of the contact surface between the swash plate 1' and the sliding shoe 2' to lubricate the high-pressure oil inside the high-pressure side plunger 4' and the sliding shoe 2' to the runway of the swash plate 1'. Such a design basically meets the lubrication between the swash plate 1' and the bearing shell 3', and is a common design method, but such a lubrication method is prone to the following problems during testing and use:
[0004] After the plunger pump is used for a certain period of time, the axial displacement of the connection between the sliding shoe 2' and the plunger 4' will gradually increase, which increases the hidden danger of the plunger pump failure due to the failure of the sliding shoe 2'.
[0005] The inner support belt on the surface of the sliding shoe 2' in contact with the swash plate 1' is often severely worn, which greatly reduces the service life of the sliding shoe 2';
[0006] The swash plate 1' of this design method often leaves clear and obvious stamping marks 12' on the working surface of the swash plate 1', and the profile of the stamping marks 12' basically matches the profile of the sealing belt of the sliding shoe 2'. As shown in the figure, the dashed line represents the stamping mark 12', which will cause the flatness of the swash plate 1' at this place to be damaged, thereby affecting the relative movement between the sliding shoe 2' and the working surface of the swash plate 1', and further reducing the service life of the sliding shoe; Figure 2
[0007] 4. The design makes the lubricating oil pressure between the swash plate shaft and the bearing bush 3' in the approximate square wave variation cycle, when the high pressure cavity of the shoe 2' is not communicated with the small oil channel 11', the pressure in the lubricating oil cavity is insufficient, the lubricating effect is reduced, if the pump is being variable at this time, it will cause the wear of the swash plate 1' and the bearing bush 3', and reduce the service life of the pump.
[0008] Design defect analysis: combined with the experience of the static pressure support of the shoe 2', it can be known that when the high pressure oil in the shoe 2' is not communicated with the small oil channel 11', the pressure is consistent with the cavity pressure of the shell, and is almost 0, so whenever the sealing ring of the shoe 2' is communicated with the small oil channel 11', the high pressure cavity in the sealing ring of the shoe 2' is communicated with the lubricating oil cavity with very low pressure, the pressure is instantaneously reduced, the static pressure support between the shoe 2' and the working surface of the swash plate 1' is broken, the shoe 2' cannot get enough support and is pressed tightly on the working surface of the swash plate 1', and the cycle is repeated, so that the working surface of the swash plate 1' leaves the stamping traces which are equivalent to the profile of the sealing ring and tangent to the small oil channel 11'. Content of the utility model
[0009] In order to solve the technical problems that the high pressure oil in the shoe of the plunger pump in the prior art cannot always keep communicated with the lubricating oil cavity through the oil channel, the pressure of the high pressure cavity in the sealing ring of the shoe is suddenly changed, the shoe hits the working surface of the swash plate, the working surface of the swash plate leaves the impact traces, and there is insufficient lubricating oil pressure between the swash plate and the bearing bush, which causes the wear of the swash plate and the bearing bush, the utility model provides a variable structure and a pump structure, and solves the above technical problems.
[0010] In order to solve the above technical problems, the utility model provides a variable structure, including a swash plate, the swash plate has opposite first face and second face, the first face is matched with a shoe, the first face is divided into high pressure side and low pressure side, the high pressure side is distributed with at least four oil holes, the high pressure cavity of at least one shoe keeps communicated with at least one oil hole, so as to guide the high pressure oil in the shoe to the second face of the swash plate.
[0011] According to one embodiment of the utility model, all the oil holes are distributed on the same circle with the center of the swash plate as the center, and the center points of the high pressure cavities of all the shoes are also distributed on the circle.
[0012] According to one embodiment of the utility model, the distance between two oil holes separated by one oil hole is constant, when one of the two oil holes is inscribed in the high pressure cavity of the shoe, the other oil hole is tangent to the high pressure cavity of the shoe, when one of the two oil holes is just disconnected from the high pressure cavity of the shoe, the other oil hole is just communicated with the high pressure cavity of the shoe.
[0013] According to one embodiment of the utility model, when the intermediate oil hole between the two oil holes is externally tangent to the high pressure cavity of the sliding shoe, one adjacent oil hole is located at the center point of the high pressure cavity of the sliding shoe.
[0014] According to one embodiment of the utility model, the swash plate is internally provided with a high pressure flow channel, and all the oil holes extend to communicate with the high pressure flow channel.
[0015] According to one embodiment of the utility model, further comprising a bush, the second face of the swash plate is supported by the bush, and the high pressure flow channel guides high pressure oil between the swash plate and the bush.
[0016] The utility model also provides a pump structure, comprising:
[0017] Variable structure;
[0018] Cylinder, the cylinder is formed with a plurality of plunger holes;
[0019] Plunger, the plunger is correspondingly assembled into the plunger hole, and one end of the plunger that extends the plunger hole is matched with the first face of the swash plate through the sliding shoe.
[0020] According to one embodiment of the utility model, the sliding shoe is formed with a spherical concave surface to match the plunger, a high pressure cavity is formed between the sliding shoe and the swash plate, and the high pressure cavity and the spherical concave surface are communicated.
[0021] According to one embodiment of the utility model, the high pressure cavity is recessed on the face of the sliding shoe matched with the first face of the swash plate, a sealing band is formed on the periphery of the high pressure cavity, and the high pressure cavity and the spherical concave surface are communicated through an oil hole.
[0022] According to one embodiment of the utility model, the sealing band, the high pressure cavity and the oil hole are coaxially arranged along the axis of the sliding shoe.
[0023] Based on the above technical scheme, the utility model can realize the following technical effects:
[0024] The variable structure of the utility model, by setting the high pressure side distribution of at least 4 oil holes of the swash plate, at least one high pressure cavity of the sliding shoe is kept in communication with at least one oil hole, so that the high pressure oil in the sliding shoe can keep on to the second face of the swash plate, and the second face of the swash plate keeps on high pressure oil lubrication, can guarantee that the oil in the swash plate is always equivalent to the pressure of the high pressure cavity of the sliding shoe, so as to eliminate the stamping trace caused by the sudden pressure loss of the sliding shoe moving to the oil hole at the present stage;
[0025] The variable structure of the utility model, specific setting oil hole's distribution, all oil holes distribute on same circle with the center of swash plate as the center, the center point of all high pressure cavities of sliding shoe also distribute on the circle, then in the process of relative motion of sliding shoe and swash plate, the high pressure cavity of sliding shoe will pass the position of oil hole and realize intercommunication, further set the distance between two oil holes which are separated by an oil hole, when one oil hole in two oil holes is tangent with the high pressure cavity in sliding shoe, the other oil hole is externally tangent with the high pressure cavity in sliding shoe, when one oil hole in two oil holes just disconnects and communicates with the high pressure cavity in sliding shoe, the other oil hole just communicates with the high pressure cavity in sliding shoe, so this can guarantee that at least one of two oil holes communicates with the high pressure cavity, further limit the position relation between intermediate oil hole and adjacent oil hole between two oil holes, can guarantee that at least one of intermediate oil hole and its adjacent oil hole communicates with the high pressure cavity,
[0026] The variable structure of the utility model, swash plate is provided with high pressure flow channel, all oil holes extend to communicate with high pressure flow channel, high pressure oil enters between swash plate and bearing bush through high pressure flow channel, then high pressure flow channel can keep the pressure equivalent to the high pressure cavity of sliding shoe, high pressure oil introduced by oil hole all converges to high pressure flow channel, then high pressure flow channel provides high pressure oil for the gap between swash plate and bearing bush, and stable oil supply is maintained.
[0027] The pump structure of the utility model, when the cylinder body rotates relative to the swash plate, the high pressure oil in the cylinder body can flow to the high pressure cavity of the corresponding sliding shoe, at least one high pressure cavity can keep communication with at least one oil hole, the high pressure oil is introduced to the second surface of the swash plate, the lubrication between the swash plate shaft and the bearing bush can be continuously realized, the wear between the bearing bush and the bearing seat is reduced, the static pressure support balance between the sliding shoe and the swash plate is maintained, the original stamping trace of the sliding shoe on the first surface of the swash plate is eliminated, the sliding shoe and the first surface of the swash plate can smoothly move relative to each other, the lubrication is guaranteed, the impact is reduced, and the service life of the sliding shoe and the swash plate is increased. BRIEF DESCRIPTION OF DRAWINGS
[0028] Figure 1 It is a structural schematic view of the plunger pump in the prior art;
[0029] Figure 2 It is a state view of the working surface of the swash plate in the prior art;
[0030] Figure 3 It is a structural schematic view of the first surface of the swash plate of the variable structure of the utility model;
[0031] Figure 4 It is a structural schematic view of the side surface of the swash plate and an internal oil circuit schematic view;
[0032] Figure 5 It is the corresponding position relation of the oil hole on the first surface of the swash plate and the high pressure cavity of the sliding shoe under the initial state;
[0033] Figure 6 For rotating a certain angle, the corresponding position relationship between the oil hole on the first surface of the swash plate and the high-pressure cavity;
[0034] Figure 7 The structural schematic view of the pump structure of the utility model;
[0035] Figure 8 The schematic view of the oil pressure distribution of the contact surface between the sliding shoe and the swash plate when the sliding shoe works in the high-pressure area;
[0036] Figure 9 The structural schematic view of the contact surface between the sliding shoe and the swash plate;
[0037] In the figure: 1-swash plate; 11-oil hole; 111-first oil hole; 112-second oil hole; 113-third oil hole; 114-fourth oil hole; 12-high-pressure flow channel; 2-sliding shoe; 21-high-pressure cavity; 22-spherical concave surface; 23-oil passage; 24-sealing band; 3-bush; 4-oil film; 5-plunger; 51-through hole; 1'-swash plate; 11'-small oil channel; 12'-punch mark; 2'-sliding shoe; 3'-bush; 4'-plunger. DETAILED DESCRIPTION
[0038] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the utility model and its application or use. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the utility model.
[0039] It should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and furthermore, it should be understood that when the terms "comprise" and / or "include" are used in the specification, there is a feature, step, operation, device, component and / or combination thereof.
[0040] The foregoing description, for purposes of explanation, sets forth specific values and arrangements of components and steps that are subject to many options. The intent is to be accurate in describing the principles and novel features of the application. Thus, although the application has been described with reference to specific embodiments thereof, it will be apparent to those of ordinary skill in the art that a number of changes can be made to the embodiments described without departing from the spirit and scope of the application. For example, the various features of the application can be combined in any combination, where possible. Accordingly, the scope of the application is to be construed as encompassing modifications and variations of the specific examples described herein, subject only to the conditions of the prior art.
[0041] In the description of the present application, it is necessary to understand that the orientation words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom" and the like indicated by the orientation or position relationship shown in the drawings are generally based on the orientation or position relationship shown in the drawings, only for the convenience of describing the present application and simplifying the description, without making the opposite statement, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, therefore, it cannot be understood as a limitation on the protection scope of the present application; the orientation words "inner, outer" refer to the inner and outer of the contour of each component itself.
[0042] For the convenience of description, spatial relative terms such as "on", "above", "upper surface", "upper" and the like can be used herein to describe the spatial position relationship of one device or feature with other devices or features as shown in the drawings. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation of the device described in the drawings. For example, if the device in the drawing is inverted, the device described as "above" or "on" other devices or structures will be positioned "below" or "under" other devices or structures. Thus, the example term "above" can include both "above" and "below" orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative description used herein is interpreted accordingly.
[0043] In addition, it should be noted that the use of the words "first", "second" and the like to define parts of components is only for the convenience of distinguishing the corresponding parts of components, and the above words have no special meaning unless otherwise stated, therefore, it cannot be understood as a limitation on the protection scope of the present application.
[0044] AsFigures 3-6 As shown, this embodiment proposes a variable structure, including a swashplate 1. The swashplate 1 has a first surface and a second surface that are opposite each other. The first surface of the swashplate 1 is engaged with a slipper 2. The first surface can be divided into a high-pressure side and a low-pressure side. The high-pressure side of the swashplate 1 has at least four oil holes 11. When multiple slippers 2 move relative to the first surface of the swashplate 1, the high-pressure chamber 21 of at least one slipper 2 can be connected to at least one oil hole 11. In this way, the high-pressure oil in the high-pressure chamber 21 of at least one slipper 2 can flow to the second surface of the swashplate 1 through the connected oil hole 11, thereby playing a role in stable lubrication.
[0045] like Figures 3-4 As shown, the first surface of the swashplate 1 is a planar structure, which mates with the slipper 2; the second surface of the swashplate 1 is a spherical surface, supported by the bearing 3. Figure 3 As shown, the first surface of the swashplate 1 is divided into two parts by a vertical dotted line. The left half is the part where the volume of the cylinder piston cavity decreases as the plunger 5 and slipper 2 rotate clockwise on the swashplate 1, i.e., the high-pressure side (also called the oil-pressing side). The right half is the part where the volume of the cylinder piston cavity increases as the plunger 5 and slipper 2 rotate clockwise on the swashplate 1, i.e., the low-pressure side (also called the oil-suction side). At least four oil holes 11 are distributed on the high-pressure side of the swashplate 1, and all oil holes 11 are distributed on the same circle centered on the center of the swashplate 1. When the slipper 2 moves relative to the swashplate 1, the high-pressure cavity 21 of at least one slipper 2 communicates with at least one oil hole 11 on the swashplate 1.
[0046] As a preferred technical solution in this embodiment, the center point of the high pressure chamber 21 of all slippers 2 is also distributed on the circle where all oil holes 11 are located.
[0047] As a preferred technical solution of this embodiment, the distance between the two oil holes 11 separated by one oil hole 11 is constant. When one of the two oil holes 11 is internally tangent to the high-pressure cavity 21 of the slipper 2, the other oil hole 11 is externally tangent to the high-pressure cavity 21 of the slipper 2. When one of the two oil holes 11 is just disconnected from the high-pressure cavity 21 of the slipper 2, the other oil hole 11 is just connected to the high-pressure cavity 21 of the slipper 2.
[0048] As a preferred technical solution of this embodiment, when the intermediate oil hole 11 located between the two oil holes 11 is externally tangent to the high-pressure cavity 21 of the slipper 2, the adjacent oil hole 11 is located at the center point of the high-pressure cavity 21 of the slipper 2.
[0049] As a preferred embodiment, a high-pressure flow channel 12 is also provided inside the swash plate 1. The first end of the high-pressure flow channel 12 is located inside the swash plate 1, and the second end extends to the second surface of the swash plate 1. Each oil hole 11 extends to communicate with the first end of the high-pressure flow channel 12. High-pressure oil introduced through the oil hole 11 enters the high-pressure flow channel 12 and then flows to the second surface of the swash plate 1. By connecting multiple oil holes 11 and providing pressurized oil to the swash plate seat together, it can be ensured that the oil inside the swash plate 1 always has a pressure equivalent to that of the high-pressure chamber 21, thereby eliminating the dents caused by the sudden pressure loss when the slipper 2 moves above the oil hole 11. Preferably, the second end of the high-pressure flow channel 12 extends to the center of the second surface of the swash plate 1.
[0050] As a preferred technical solution of this embodiment, it also includes a bearing 3, the second surface of the swash plate 1 is fitted with the bearing 3, and high-pressure oil enters between the swash plate 1 and the bearing 3 through the high-pressure flow channel 12 to form an oil film 4.
[0051] Based on the aforementioned technical solution, the working principle of the variable structure in this embodiment is as follows: Figures 5-6 As shown, taking four oil holes 11 and nine plungers 5 and slippers 2 as an example, the circular dashed lines represent the distribution of slippers 2 on the first surface of the swashplate 1. The inner circle of dashed lines represents the high-pressure chamber 21 region of slipper 2, and the annular area between the inner and outer circles of dashed lines represents the sealing band 24 of slipper 2. The four oil holes 11 are designated as first oil hole 111, second oil hole 112, third oil hole 113, and fourth oil hole 114. The circumferential distance between first oil hole 111 and third oil hole 113, and the circumferential distance between second oil hole 112 and fourth oil hole 114 are equal. Figure 6 As shown, the first oil hole 111 is internally tangent to the high-pressure chamber 21 of the slipper 2, and the third oil hole 113 is externally tangent to the high-pressure chamber 21 of the next slipper 2. At the current position, the first oil hole 111 is connected to the high-pressure chamber 21 of the slipper 2, while the third oil hole 113 is disconnected from the next slipper 2. As the slipper 2 continues to rotate clockwise, the first oil hole 111 gradually disconnects from the high-pressure chamber 21 of the slipper 2, while the third oil hole 113 gradually connects to the high-pressure chamber 21 of the slipper 2. That is, at least one of the first oil holes 111 and the third oil hole 113 is connected to at least one high-pressure chamber 21 of the slipper 2; similarly, at least one of the second oil holes 112 and the fourth oil hole 114 is connected to at least one high-pressure chamber 21 of the slipper 2. Figure 5 As shown, the first oil hole 111 is located at the center of the high-pressure chamber 21 of one slipper 2, the second oil hole 112 is externally tangent to the high-pressure chamber 21 of the next slipper 2, and the third oil hole 113 is also externally tangent to the high-pressure chamber 21 of the next slipper 2. Because the movement of the slipper on the swashplate is repetitive and regular, such as... Figure 5As shown, for a 9-piston cylinder block, it is only necessary to consider whether at least one oil hole 11 can always be connected to the high-pressure chamber 21 of the slipper 2 during the time it rotates 360° / 9 = 40° until the high-pressure chamber 21 of the next slipper 2 becomes tangent to the second oil hole 112. Combining the relative positions of the second oil hole 112 and the fourth oil hole 114, it can be known that at least one of them will be connected to the high-pressure chamber 21; combining the relative positions of the first oil hole 111 and the third oil hole 113, it can be known that at least one of them will be connected to the high-pressure chamber 21. Therefore, the high-pressure flow channel 12 of the swashplate 1 will always be connected to the high-pressure chamber 21 of at least one slipper 2.
[0052] The above scheme corresponds to the oil hole distribution of a 9-piston cylinder. As can be seen from the design requirements of the piston pump, for a piston pump with more pistons, the pistons are more compactly distributed on the cylinder block distribution circle (the space occupied by the high-pressure chamber is larger than the interval between the high-pressure chambers). It is easier to meet the requirements of the oil passage opening design according to the above scheme. Example
[0053] like Figures 7-9 As shown, this embodiment provides a pump structure, including the aforementioned variable structure, and also includes a cylinder and a plunger 5. The cylinder has multiple plunger holes, and the plunger 5 is set corresponding to the plunger holes. The plunger 5 is assembled into the plunger holes, and one end of the plunger 5 extending out of the plunger hole cooperates with the first surface of the swashplate 1 through the slipper 2.
[0054] like Figure 7 As shown, the plunger 5 is a hollow plunger, and the end of the plunger 5 that mates with the slipper 2 is ball-shaped. The plunger 5 has a through hole 51 to facilitate the entry of high-pressure oil into the slipper 2.
[0055] like Figures 8-9 As shown, the end of the slipper 2 that mates with the plunger 5 has a spherical concave surface 22. The ball-shaped end of the plunger 5 can extend into the spherical concave surface 22. A high-pressure chamber 21 is recessed on the surface of the slipper 2 that mates with the first surface of the swashplate 1. A sealing band 24 is formed on the outer periphery of the high-pressure chamber 21. An oil passage hole 23 is also provided inside the slipper 2. The spherical concave surface 22 and the high-pressure chamber 21 are connected through the oil passage hole 23.
[0056] As a preferred technical solution in this embodiment, the high-pressure chamber 21 is circular, the sealing strip 24 is annular, and the oil passage 23, the high-pressure chamber 21 and the sealing strip 24 are coaxially arranged along the axis of the slipper 2.
[0057] Based on the above technical solution, the pump structure of this embodiment has an oil hole 11 on the swashplate 1, which can continuously achieve lubrication between the swashplate 1 and the bearing 3, reducing wear. Secondly, it maintains the hydrostatic support balance between the slipper 2 and the swashplate 1, and the oil pressure distribution on the contact surface between the slipper 2 and the swashplate 1 when the slipper 2 is working in the high-pressure area is as follows:Figure 8 As shown, stable support is established between the sliding shoe 2 and the inclined plane 1, and there is always oil film lubrication between the sliding shoe 2 and the inclined disc 1, thereby eliminating the original stamping marks of the sliding shoe 2 on the inclined disc 1, both of which can make the sliding shoe 2 and the inclined disc 1 smoothly relative movement, ensure lubrication, reduce impact, and increase the service life of the sliding shoe 2 and the inclined disc 1. Thirdly, the pressure pulsation inside the oil hole 11 is eliminated, the service life of the inclined disc 1 is prolonged, and it is also helpful to reduce the noise during the operation of the plunger pump. Finally, the design structure is simple, easy to process, and can directly improve the existing products.
[0058] The embodiments of the utility model are described in detail above in combination with the drawings, but the utility model is not limited to the above-mentioned embodiments, and various changes can be made within the knowledge range possessed by those skilled in the art without departing from the purpose of the utility model.
Claims
1. A variable structure, characterized by, The invention relates to a swash plate (1) having opposite first and second faces, the first face being matched with a shoe (2), the first face being divided into a high pressure side and a low pressure side, the high pressure side being provided with at least four oil holes (11), the high pressure cavity (21) of at least one shoe (2) being in communication with at least one oil hole (11) to guide the high pressure oil in the shoe (2) to the second face of the swash plate (1).
2. A variable structure according to claim 1, wherein, All the oil holes (11) are distributed on the same circle with the center of the swash plate (1) as the center, and the center points of the high pressure cavities (21) of all the shoes (2) are also distributed on the circle.
3. A variable structure according to claim 2, wherein, The distance between two oil holes (11) separated by one oil hole (11) is constant, when one of the two oil holes (11) is inscribed in the high pressure cavity (21) of the shoe (2), the other oil hole (11) is circumscribed in the high pressure cavity (21) of the shoe (2); when one of the two oil holes (11) is just disconnected from the high pressure cavity (21) of the shoe (2), the other oil hole (11) is just connected to the high pressure cavity (21) of the shoe (2).
4. A variable structure according to any one of claims 2-3, characterized in that, When the middle oil hole (11) between the two oil holes (11) is circumscribed in the high pressure cavity (21) of the shoe (2), one of the adjacent oil holes (11) is located at the center point of the high pressure cavity (21) of the shoe (2).
5. A variable structure according to claim 1, wherein, The swash plate (1) is provided with a high pressure flow channel (12), and all the oil holes (11) extend to communicate with the high pressure flow channel (12).
6. A variable structure according to claim 5, wherein, The invention further relates to a bearing bush (3) supporting the second face of the swash plate (1), and the high pressure flow channel (12) guides the high pressure oil between the swash plate (1) and the bearing bush (3).
7. A pump structure, characterized by, The invention relates to: a variable structure according to any one of claims 1-6; a cylinder block formed with a plurality of plunger holes; a plunger (5) fitted into the plunger holes, and an end of the plunger (5) extending out of the plunger hole matched with the first face of the swash plate (1) through a shoe (2).
8. A pump structure according to claim 7, wherein The shoe (2) is formed with a spherical concave surface (22) matched with the plunger (5), and a high pressure cavity (21) is formed between the shoe (2) and the swash plate (1), and the high pressure cavity (21) and the spherical concave surface (22) are in communication.
9. A pump structure according to claim 8, wherein The high pressure cavity (21) is concavely formed on the face of the shoe (2) matched with the first face of the swash plate (1), and a sealing band (24) is formed on the periphery of the high pressure cavity (21), and the high pressure cavity (21) and the spherical concave surface (22) are in communication through an oil passage hole (23).
10. A pump structure according to claim 9, wherein The sealing band (24), the high pressure cavity (21) and the oil passage hole (23) are coaxially arranged along the axis of the shoe (2).