Shuttle structure parameter matching design method for axial plunger pump

Abstract

The invention belongs to the technical field of hydraulic transmission and hydraulic elements, and particularly relates to an axial plunger pump Shuttle structure parameter matching design method. According to the method, valve plate angles corresponding to starting positions and stopping positions of a low-pressure kidney-shaped groove and a high-pressure kidney-shaped groove are calculated, and whether the maximum compensation volume actually provided by a micro hydraulic cylinder is larger than the maximum compensation volume of a micro hydraulic cylinder or not is judged and controlled. Therefore, the efficient Shuttle structure parameter matching design method is obtained, and the matching design of the Shuttle structure parameters can be rapidly completed.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic transmission and hydraulic components, and in particular relates to a structural parameter matching design method for an axial piston pump "Shuttle". Background Art

[0002] As a hydraulic power element, the swash plate axial piston pump is widely used in situations with large loads and high power due to its advantages of high output pressure, high efficiency, simple and compact structure and convenient flow regulation.

[0003] In 2001, INNAS of the Netherlands first proposed the "Shuttle" technology in hydraulic transformers. In 2021, in order to reduce the noise of axial piston pumps and improve the efficiency of axial piston pumps, INNAS further introduced the "Shuttle" technology into axial piston pumps. In 2022, INNAS verified through experiments that the "Shuttle" technology can significantly improve the efficiency of axial piston pumps.

[0004] The "Shuttle" technology is based on the traditional axial piston pump structure. A micro hydraulic cylinder similar to a shuttle valve (Shuttle) is added between any two adjacent piston chambers in the axial piston pump cylinder body, and the position of the high and low pressure waist grooves of the distribution plate is re-matched. After the "Shuttle" technology is introduced into the traditional axial piston pump, the axial piston pump can realize the smooth high and low pressure switching process of the piston chamber pressure in a wide range of working conditions, so that the axial piston pump can benefit from vibration reduction, noise reduction, stability enhancement, efficiency enhancement, and life extension at the same time. At the same time, the introduction of the "Shuttle" technology will not change the appearance and installation interface of the axial piston pump, and can realize the in-situ replacement of the traditional axial piston pump, which is conducive to the in-situ upgrade of the axial piston pumps used in large quantities in existing equipment.

[0005] However, after the "Shuttle" technology is introduced into the traditional axial piston pump, a series of structural parameters will be involved in the matching design. These parameters are coupled with each other. If we only rely on the trial method, constantly give the design values ​​of these parameters, and then simulate and verify the design effect, the design efficiency will be very low. As a new technology, there is no public matching design method yet. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] The technical problem to be solved by the present invention is: "Shuttle" technology is a new technology proposed in the field of axial piston pumps in recent years. Introducing this technology into traditional axial piston pumps can benefit the axial piston pumps in many aspects such as vibration reduction, noise reduction, stability enhancement, efficiency enhancement, and life extension. The introduction of "Shuttle" technology involves a series of structural parameters that need to be matched and designed. If it only relies on trial methods, constantly giving design values ​​of these parameters, and then simulating and verifying the design effect, it will lead to very low design efficiency. As a new technology, there is no public matching design method yet. The present invention will disclose an efficient "Shuttle" structural parameter matching design method, which can quickly complete the matching design of "Shuttle" structural parameters.

[0008] (II) Technical solution

[0009] In order to solve the above technical problems, the present invention provides a structural parameter matching design method of an axial piston pump "Shuttle", which adopts the following steps:

[0010] Step 1: Make the following simplifications:

[0011] (1) Assume that the plunger cavity is ideally leak-free;

[0012] (2) Ignore the inertial effect of the spherical piston motion;

[0013] Step 2: Calculate the second distribution plate angle α2 and the fourth distribution plate angle α4; the second distribution plate angle α2 describes the distribution plate angle corresponding to the cut-off position of the high-pressure waist-shaped slot, and the fourth distribution plate angle α4 describes the distribution plate angle corresponding to the cut-off position of the low-pressure waist-shaped slot;

[0014] Step 3: Calculate the first distribution plate angle α1; the first distribution plate angle α1 describes the distribution plate angle corresponding to the starting position of the high-pressure waist-shaped groove;

[0015] Step 4: Calculate the required maximum compensation volume of the micro hydraulic cylinder;

[0016] Step 5: Carry out engineering design of the micro hydraulic cylinder to determine the maximum compensation volume that the micro hydraulic cylinder can actually provide under practical constraints;

[0017] Step 6: Determine whether the maximum compensation volume that the micro hydraulic cylinder in step 5 can actually provide is greater than the maximum compensation volume of the micro hydraulic cylinder in step 4, that is, determine whether the narrow structural space between the two plunger holes of the cylinder body is sufficient to arrange a sufficiently large micro hydraulic cylinder;

[0018] Step 7: Calculate the third distribution plate angle α3; the third distribution plate angle α3 describes the distribution plate angle corresponding to the starting position of the low-pressure waist-shaped groove.

[0019] Among them, in the step 2, the angles α2 and α4 of the distribution plate are calculated; the plunger cavity is made to move counterclockwise to the bottom dead center, that is, when the plunger cavity oil discharge stroke ends, the plunger cavity and the high-pressure waist-shaped groove are completely separated, so:

[0020]

[0021] Similarly, there are:

[0022]

[0023] Among them, θ0 is the angle of the waist groove at the tail end of the plunger cavity.

[0024] In step 2, the first valve plate angle α1 is calculated; according to the "shuttle" technology principle, α1 should be large enough to ensure that the plunger cavity has a large enough pre-pressurization capacity; let the pump inlet pressure p L is a constant pressure p1, the pump outlet pressure p H The variation range is [p1, p2]. Considering the maximum pressure condition of the pump outlet pressure p2, the plunger cavity needs to reduce the oil pressure in the cavity to p H Pre-boost from p1 to p2; to complete the boost process, the required valve plate angle α1 is

[0025]

[0026] In the above formula, V d0 is the volume of the plunger cavity at the top dead center, β is the effective volume elastic modulus of the oil, d is the plunger diameter, R p is the radius of the distribution circle of the plunger cavity on the cylinder body, and α is the inclination angle of the swash plate.

[0027] Among them, in the step 4, the required maximum compensation volume of the micro hydraulic cylinder is calculated; according to the "shuttle" technical principle, after the plunger cavity is disconnected from the low-pressure waist-shaped groove and before it is connected to the high-pressure waist-shaped groove, when the plunger cavity pressure is pre-pressurized to the pump outlet pressure, the plunger cavity expansion volume formed by the movement of the spherical piston in the micro hydraulic cylinder will be used to compensate for the plunger cavity compression volume caused by the plunger movement, so as to limit the plunger cavity pressure from further increasing and realize the connection between the plunger cavity and the high-pressure waist-shaped groove without pressure difference; considering that when the pump outlet pressure is the lowest working pressure p1, the volume compensation capacity of the micro hydraulic cylinder is required to be the largest; under the corresponding working conditions, the required maximum compensation volume V of the micro hydraulic cylinder is obtained shuttle ,have

[0028]

[0029] Among them, in the step 5, the micro hydraulic cylinder engineering design is carried out; the micro hydraulic cylinder is arranged in the cylinder body, and the inner diameter d of the micro hydraulic cylinder is determined. s and piston travel Ls , and piston ball diameter d ball , the inlet areas Asl and Asr at both ends of the micro hydraulic cylinder; when carrying out the three-dimensional design of the micro hydraulic cylinder, the compact structural space of the two adjacent plunger cavities should be used to the maximum extent possible while meeting the requirements of rigidity, machinability, etc.; determine the maximum compensation volume V that the micro hydraulic cylinder can actually provide under actual constraints s ' huttle , calculated by the following formula

[0030]

[0031] Among them, in step 6, it is determined that V s ' huttle Is it greater than V shuttle , that is, to judge whether the narrow structural space between the two plunger holes of the cylinder body is sufficient to arrange a sufficiently large micro hydraulic cylinder.

[0032] Among them, in step 6, if the judgment result is no, that is, the narrow structural space between the two plunger holes of the cylinder body is not enough to arrange a sufficiently large micro hydraulic cylinder, the maximum compensation volume V of the micro hydraulic cylinder that can actually be designed is s ' huttle Smaller than the required design volume V shuttle , then the valve plate angle α1 is designed within the following range

[0033]

[0034] Among them, if the design value of the distribution plate angle α1 is biased towards the left boundary, it means that for the latter high-pressure interval of the pump outlet pressure variation range [p1, p2], due to the insufficient pre-pressurization capacity of the plunger cavity, the plunger cavity will be connected with the high-pressure waist-shaped groove in advance when the pressure is not increased to the pump outlet pressure level, forming a reverse flow backflow, that is, sacrificing the distribution characteristics of the high-pressure working condition range; if the design value of the sealing belt α1 is biased towards the right boundary, it means that for the first low-pressure interval of the pump outlet pressure variation range [p1, p2], due to the insufficient compensation capacity of the micro-hydraulic cylinder, the plunger cavity pressure will be over-pressurized to exceed the pump outlet pressure level and connect with the high-pressure waist-shaped groove, which will form a positive flow impact, that is, sacrificing the distribution characteristics of the low-pressure working condition;

[0035] Therefore, when the actual structure does not allow the design of a sufficiently large micro hydraulic cylinder, that is, under the structural constraint that the ideal flow distribution process under full pressure conditions cannot be achieved, the size of the distribution plate angle α1 can be adjusted to actively control the operating range of the ideal pressure switching process; according to the actual target application requirements, the design value of α1 is determined according to actual needs, and then the next step of design work is carried out.

[0036] Among them, in step 6, if the judgment result is yes, that is, the cylinder space is sufficient to arrange the compensation volume V shuttle If you have a micro hydraulic cylinder, you can directly carry out the next step of design work.

[0037] Among them, in step 7, the third valve plate angle α3 is calculated; considering the extreme working condition, that is, the pump outlet is the maximum working pressure p2, the plunger cavity runs from the bottom dead center to connect with the low-pressure waist groove. In this process, the plunger cavity pressure drops from p2 to p1, and the required valve plate angle α3 can be deduced as

[0038]

[0039] In the above formula, V d2 It is the volume of the plunger cavity when it is at the bottom dead center of the distribution plate.

[0040] (III) Beneficial effects

[0041] Compared with the prior art, the "Shuttle" technology is a new technology proposed in the field of axial piston pumps in recent years. Introducing this technology into traditional axial piston pumps can benefit the axial piston pumps in many aspects such as vibration reduction, noise reduction, stability enhancement, efficiency enhancement, and life extension. The introduction of the "Shuttle" technology involves a series of structural parameters that need to be matched and designed. If it only relies on trial methods, constantly giving design values ​​for these parameters, and then simulating and verifying the design effect, it will lead to very low design efficiency. As a new technology, there is no public matching design method yet. The present invention provides an efficient "Shuttle" structural parameter matching design method that can quickly complete the matching design of the "Shuttle" structural parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1a and Figure 1b This is a comparison between a traditional cylinder block and a cylinder block with the "shuttle" technology introduced. Figure 1a For the traditional cylinder, Figure 1b This is the cylinder block after the introduction of the "shuttle" technology.

[0043] Figure 2 Schematic diagram of parameters related to the distribution plate design.

[0044] In the figure, - cylinder angle;

[0045] θ0-Angle of waist groove at the end of plunger cavity;

[0046] α1-the first valve plate angle, the starting angle of the high-pressure waist-shaped groove, describes the valve plate angle corresponding to the starting position of the high-pressure waist-shaped groove;

[0047] α2-the second distribution plate angle, the cut-off angle of the high-pressure waist-shaped groove, describes the distribution plate angle corresponding to the cut-off position of the high-pressure waist-shaped groove;

[0048] α3-the third valve plate angle, the starting angle of the low-pressure waist-shaped groove, describes the valve plate angle corresponding to the starting position of the low-pressure waist-shaped groove;

[0049] α4-the fourth distribution plate angle, the cut-off angle of the low-pressure waist-shaped groove, describes the distribution plate angle corresponding to the cut-off position of the low-pressure waist-shaped groove.

[0050] Figure 3 Design a flow chart for parameter matching of the "Shuttle" structure. DETAILED DESCRIPTION

[0051] In order to make the purpose, content, and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the accompanying drawings and examples.

[0052] Example 1

[0053] This embodiment provides a method for designing structural parameters matching of an axial piston pump "Shuttle", the method adopts the following steps:

[0054] Step 1: Make the following simplifications:

[0055] (1) Assume that the plunger cavity is ideally leak-free;

[0056] (2) Ignore the inertial effect of the spherical piston motion;

[0057] Step 2: Calculate the second distribution plate angle α2 and the fourth distribution plate angle α4; Figure 2 As shown, the second distribution plate angle α2 describes the distribution plate angle corresponding to the cut-off position of the high-pressure waist-shaped slot, and the fourth distribution plate angle α4 describes the distribution plate angle corresponding to the cut-off position of the low-pressure waist-shaped slot;

[0058] Step 3: Calculate the first distribution plate angle α1; the first distribution plate angle α1 describes the distribution plate angle corresponding to the starting position of the high-pressure waist-shaped groove;

[0059] Step 4: Calculate the required maximum compensation volume of the micro hydraulic cylinder;

[0060] Step 5: Carry out engineering design of the micro hydraulic cylinder to determine the maximum compensation volume that the micro hydraulic cylinder can actually provide under practical constraints;

[0061] Step 6: Determine whether the maximum compensation volume that the micro hydraulic cylinder in step 5 can actually provide is greater than the maximum compensation volume of the micro hydraulic cylinder in step 4, that is, determine whether the narrow structural space between the two plunger holes of the cylinder body is sufficient to arrange a sufficiently large micro hydraulic cylinder;

[0062] Step 7: Calculate the third distribution plate angle α3; the third distribution plate angle α3 describes the distribution plate angle corresponding to the starting position of the low-pressure waist-shaped groove.

[0063] Among them, in the step 2, the angles α2 and α4 of the distribution plate are calculated; the plunger cavity is made to move counterclockwise to the bottom dead center, that is, when the plunger cavity oil discharge stroke ends, the plunger cavity and the high-pressure waist-shaped groove are completely separated, so:

[0064]

[0065] Similarly, there are:

[0066]

[0067] Among them, θ0 is the angle of the waist groove at the tail end of the plunger cavity.

[0068] In step 2, the first valve plate angle α1 is calculated; according to the "shuttle" technology principle, α1 should be large enough to ensure that the plunger cavity has a large enough pre-pressurization capacity; let the pump inlet pressure p L is a constant pressure p1, the pump outlet pressure p H The variation range is [p1, p2]. Considering the maximum pressure condition of the pump outlet pressure p2, the plunger cavity needs to reduce the oil pressure in the cavity to p H Pre-boost from p1 to p2; to complete the boost process, the required valve plate angle α1 is

[0069]

[0070] In the above formula, V d0 is the volume of the plunger cavity at the top dead center, β is the effective volume elastic modulus of the oil, d is the plunger diameter, R p is the radius of the distribution circle of the plunger cavity on the cylinder body, and α is the inclination angle of the swash plate.

[0071] Among them, in the step 4, the required maximum compensation volume of the micro hydraulic cylinder is calculated; according to the "shuttle" technical principle, after the plunger cavity is disconnected from the low-pressure waist-shaped groove and before it is connected to the high-pressure waist-shaped groove, when the plunger cavity pressure is pre-pressurized to the pump outlet pressure, the plunger cavity expansion volume formed by the movement of the spherical piston in the micro hydraulic cylinder will be used to compensate for the plunger cavity compression volume caused by the plunger movement, so as to limit the plunger cavity pressure from further increasing and realize the connection between the plunger cavity and the high-pressure waist-shaped groove without pressure difference; considering that when the pump outlet pressure is the lowest working pressure p1, the volume compensation capacity of the micro hydraulic cylinder is required to be the largest; under the corresponding working conditions, the required maximum compensation volume V of the micro hydraulic cylinder is obtained shuttle ,have

[0072]

[0073] Among them, in the step 5, the micro hydraulic cylinder engineering design is carried out; the micro hydraulic cylinder is arranged in the cylinder body, and the inner diameter d of the micro hydraulic cylinder is determined. s and piston travel L s , and piston ball diameter d ball , the inlet areas Asl and Asr at both ends of the micro hydraulic cylinder; when carrying out the three-dimensional design of the micro hydraulic cylinder, the compact structural space of the two adjacent plunger cavities should be used to the maximum extent possible while meeting the requirements of rigidity, machinability, etc.; determine the maximum compensation volume V that the micro hydraulic cylinder can actually provide under actual constraints s ' huttle , calculated by the following formula

[0074]

[0075] Among them, in step 6, it is determined that V s ' huttle Is it greater than V shuttle , that is, to judge whether the narrow structural space between the two plunger holes of the cylinder body is sufficient to arrange a sufficiently large micro hydraulic cylinder.

[0076] Among them, in step 6, if the judgment result is no, that is, the narrow structural space between the two plunger holes of the cylinder body is not enough to arrange a sufficiently large micro hydraulic cylinder, the maximum compensation volume V of the micro hydraulic cylinder that can actually be designed is s ' huttle Smaller than the required design volume V shuttle , then the valve plate angle α1 is designed within the following range

[0077]

[0078] Among them, if the design value of the distribution plate angle α1 is biased towards the left boundary, it means that for the latter high-pressure interval of the pump outlet pressure variation range [p1, p2], due to the insufficient pre-pressurization capacity of the plunger cavity, the plunger cavity will be connected with the high-pressure waist-shaped groove in advance when the pressure is not increased to the pump outlet pressure level, forming a reverse flow backflow, that is, sacrificing the distribution characteristics of the high-pressure working condition range; if the design value of the sealing belt α1 is biased towards the right boundary, it means that for the first low-pressure interval of the pump outlet pressure variation range [p1, p2], due to the insufficient compensation capacity of the micro-hydraulic cylinder, the plunger cavity pressure will be over-pressurized to exceed the pump outlet pressure level and connect with the high-pressure waist-shaped groove, which will form a positive flow impact, that is, sacrificing the distribution characteristics of the low-pressure working condition;

[0079] Therefore, when the actual structure does not allow the design of a sufficiently large micro hydraulic cylinder, that is, under the structural constraint that the ideal flow distribution process under full pressure conditions cannot be achieved, the size of the distribution plate angle α1 can be adjusted to actively control the operating range of the ideal pressure switching process; according to the actual target application requirements, the design value of α1 is determined according to actual needs, and then the next step of design work is carried out.

[0080] Among them, in step 6, if the judgment result is yes, that is, the cylinder space is sufficient to arrange the compensation volume V shuttle If you have a micro hydraulic cylinder, you can directly carry out the next step of design work.

[0081] Among them, in step 7, the third valve plate angle α3 is calculated; considering the extreme working condition, that is, the pump outlet is the maximum working pressure p2, the plunger cavity runs from the bottom dead center to connect with the low-pressure waist groove. In this process, the plunger cavity pressure drops from p2 to p1, and the required valve plate angle α3 can be deduced as

[0082]

[0083] In the above formula, V d2 It is the volume of the plunger cavity when it is at the bottom dead center of the distribution plate.

[0084] Summarizing the above process, we can sort out the following Figure 3 The parameter matching design process of the "Shuttle" structure shown in the figure. Based on the flow chart, a special program is written to carry out the "Shuttle" structure parameter matching for a certain axial piston pump. The main parameters of the axial piston pump are: displacement: 125ml / r; working speed: 1000r / min~3000r / min; oil replenishment pressure: 2.5MPa; working high pressure range: 2.5MPa~50MPa. The design results are shown in Table 1.

[0085] Table 1 Design results

[0086]

[0087] It should be noted that the spherical piston in the micro hydraulic cylinder is a universal standard part, and the ball diameter design needs to refer to the national standard GBT308-2002 or the selection table of the steel ball and ceramic ball manufacturer. In order to maximize the response speed of the piston, the spherical piston uses a low-density ceramic ball.

[0088] In addition, according to the matching design process of the "Shuttle" structural parameters (such as Figure 3 In order to realize the smooth high and low pressure switching process of the plunger chamber in the entire working pressure range of the axial piston pump, the micro hydraulic cylinder needs to have at least 507.25mm 3However, due to the limited space of the cylinder, the actual structure can only arrange a maximum compensation volume of 324.89mm 3 micro hydraulic cylinder. Therefore, the program gives the feasible design range of the waist groove angle α1 as [32.45~36.85]°. As mentioned earlier, when the cylinder body is limited by the small space and it is impossible to achieve ideal flow distribution under all working conditions, if the value of α1 is biased towards the lower limit, the flow distribution characteristics of the low-pressure working section are guaranteed, and the flow distribution characteristics of the high-pressure working section are sacrificed. On the contrary, if the value of α1 is biased towards the upper limit, the flow distribution characteristics of the high-pressure working section are guaranteed, and the flow distribution characteristics of the low-pressure working section are sacrificed. In this case, α1 takes the design lower limit of 32.45°.

[0089] Parameter matching design flow chart based on "Shuttle" structure ( Figure 3 ) for automatically matching the structural parameters of the "Shuttle", which takes only 0.01 seconds to run, proving that the method disclosed in the present invention is very efficient.

[0090] In summary, the present invention belongs to the technical field of hydraulic transmission and hydraulic components, and specifically relates to a "Shuttle" structural parameter matching design method for an axial piston pump. The "Shuttle" technology is based on the structure of a traditional axial piston pump. A micro hydraulic cylinder similar to a shuttle valve (Shuttle) is added between any two adjacent piston chambers of the axial piston pump cylinder body, and the positions of the high and low pressure waist grooves of the distribution plate are re-matched. After the "Shuttle" technology is introduced into the traditional axial piston pump, the axial piston pump can benefit from multiple aspects such as vibration reduction, noise reduction, stability enhancement, efficiency enhancement, and life extension. At the same time, the introduction of the "Shuttle" technology will not change the external contour and installation interface of the axial piston pump, and can realize the in-situ replacement of the traditional axial piston pump, which is conducive to the in-situ upgrade of the axial piston pumps used in large quantities in existing equipment. However, after the "Shuttle" technology is introduced into the traditional axial piston pump, a series of structural parameter matching designs will be involved. These parameters are coupled with each other. If only relying on the trial method, constantly giving the design values ​​of these parameters, and then simulating and verifying the design effect, the design efficiency will be very low. As a new technology, there is no public matching design method yet. The present invention provides an efficient "Shuttle" structural parameter matching design method.

[0091] The method calculates the angle of the valve plate corresponding to the starting position and the end position of the low-pressure waist-shaped groove and the high-pressure waist-shaped groove, and judges and controls whether the maximum compensation volume that the micro-hydraulic cylinder can actually provide is greater than the maximum compensation volume of the micro-hydraulic cylinder. Thus, an efficient "Shuttle" structural parameter matching design method is obtained, which can quickly complete the matching design of the "Shuttle" structural parameters.

[0092] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A structural parameter matching design method for an axial piston pump "Shuttle", characterized in that: The method employs the following steps: Step 1: Make the following simplifications: (1) Assume that the plunger cavity is ideally leak-free; (2) Ignore the inertial effect of the spherical piston motion; Step 2: Calculate the second distribution plate angle α2 and the fourth distribution plate angle α4; the second distribution plate angle α2 describes the distribution plate angle corresponding to the cut-off position of the high-pressure waist-shaped slot, and the fourth distribution plate angle α4 describes the distribution plate angle corresponding to the cut-off position of the low-pressure waist-shaped slot; Step 3: Calculate the first distribution plate angle α1; the first distribution plate angle α1 describes the distribution plate angle corresponding to the starting position of the high-pressure waist-shaped groove; Step 4: Calculate the required maximum compensation volume of the micro hydraulic cylinder; Step 5: Carry out engineering design of the micro hydraulic cylinder to determine the maximum compensation volume that the micro hydraulic cylinder can actually provide under practical constraints; Step 6: Determine whether the maximum compensation volume that the micro hydraulic cylinder in step 5 can actually provide is greater than the maximum compensation volume of the micro hydraulic cylinder in step 4, that is, determine whether the narrow structural space between the two plunger holes of the cylinder body is sufficient to arrange a sufficiently large micro hydraulic cylinder; Step 7: Calculate the third distribution plate angle α3; the third distribution plate angle α3 describes the distribution plate angle corresponding to the starting position of the low-pressure waist-shaped groove.

2. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 1, characterized in that: In step 2, the angles α2 and α4 of the distribution plate are calculated; the plunger cavity is moved counterclockwise to the bottom dead center, that is, when the plunger cavity oil discharge stroke ends, the plunger cavity and the high-pressure waist-shaped groove are completely separated, so: Similarly, there are: Among them, θ0 is the angle of the waist groove at the tail end of the plunger cavity.

3. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 2, characterized in that: In step 2, the first valve plate angle α1 is calculated; according to the "shuttle" technology principle, α1 should be large enough to ensure that the plunger cavity has a large enough pre-pressurization capacity; let the pump inlet pressure p L is a constant pressure p1, the pump outlet pressure p H The variation range is [p1, p2]. Considering the maximum pressure condition of the pump outlet pressure p2, the plunger cavity needs to reduce the oil pressure in the cavity to p1 during the deadlock stage. H Pre-boost from p1 to p2; to complete the boost process, the required valve plate angle α1 is In the above formula, V d0 is the volume of the plunger cavity at the top dead center, β is the effective volume elastic modulus of the oil, d is the plunger diameter, R p is the radius of the distribution circle of the plunger cavity on the cylinder body, and α is the inclination angle of the swash plate.

4. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 3, characterized in that: In step 4, the required maximum compensation volume of the micro hydraulic cylinder is calculated; according to the "shuttle" technical principle, after the plunger cavity is disconnected from the low-pressure waist-shaped groove and before it is connected to the high-pressure waist-shaped groove, when the plunger cavity pressure is pre-pressurized to the pump outlet pressure, the plunger cavity expansion volume formed by the movement of the spherical piston in the micro hydraulic cylinder will be used to compensate for the plunger cavity compression volume caused by the plunger movement, so as to limit the plunger cavity pressure from further increasing and realize the connection between the plunger cavity and the high-pressure waist-shaped groove without pressure difference; considering that the pump outlet pressure is the lowest working pressure p1, the volume compensation capacity of the micro hydraulic cylinder is required to be the largest; under the corresponding working conditions, the required maximum compensation volume V of the micro hydraulic cylinder is obtained shuttle ,have 5. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 4, characterized in that: In step 5, the micro hydraulic cylinder engineering design is carried out; the micro hydraulic cylinder is arranged in the cylinder body, and the inner diameter d of the micro hydraulic cylinder is determined. s and piston travel L s , and piston ball diameter d ball , the inlet areas Asl and Asr at both ends of the micro hydraulic cylinder; when carrying out the three-dimensional design of the micro hydraulic cylinder, the compact structural space of the two adjacent plunger cavities should be used to the maximum extent possible while meeting the requirements of rigidity, machinability, etc.; determine the maximum compensation volume V that the micro hydraulic cylinder can actually provide under actual constraints s ' huttle , calculated by the following formula 6. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 5, characterized in that: In step 6, it is determined that V s ' huttle Is it greater than V shuttle , that is, to judge whether the narrow structural space between the two plunger holes of the cylinder body is sufficient to arrange a sufficiently large micro hydraulic cylinder.

7. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 6, characterized in that: In step 6, if the result of the judgment is no, that is, the narrow structural space between the two plunger holes of the cylinder body is not enough to arrange a sufficiently large micro hydraulic cylinder, the maximum compensation volume V of the micro hydraulic cylinder that can actually be designed is s ' huttle Smaller than the required design volume V shuttle , then the valve plate angle α1 is designed within the following range Among them, if the design value of the distribution plate angle α1 is biased towards the left boundary, it means that for the latter high-pressure interval of the pump outlet pressure variation range [p1, p2], due to the insufficient pre-pressurization capacity of the plunger cavity, the plunger cavity will be connected with the high-pressure waist-shaped groove in advance when the pressure is not increased to the pump outlet pressure level, forming a reverse flow backflow, that is, sacrificing the distribution characteristics of the high-pressure working condition range; if the design value of the sealing belt α1 is biased towards the right boundary, it means that for the first low-pressure interval of the pump outlet pressure variation range [p1, p2], due to the insufficient compensation capacity of the micro-hydraulic cylinder, the plunger cavity pressure will be over-pressurized to exceed the pump outlet pressure level and connect with the high-pressure waist-shaped groove, which will form a positive flow impact, that is, sacrificing the distribution characteristics of the low-pressure working condition; Therefore, when the actual structure does not allow the design of a sufficiently large micro hydraulic cylinder, that is, under the structural constraint that the ideal flow distribution process under full pressure conditions cannot be achieved, the size of the distribution plate angle α1 can be adjusted to actively control the operating range of the ideal pressure switching process; according to the actual target application requirements, the design value of α1 is determined according to actual needs, and then the next step of design work is carried out.

8. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 7, characterized in that: In step 6, if the judgment result is yes, that is, the cylinder space is sufficient to arrange the compensation volume V shuttle If you have a micro hydraulic cylinder, you can directly proceed to the next step of design.

9. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 8, characterized in that: In step 7, the third valve plate angle α3 is calculated; considering the extreme working condition, that is, the pump outlet is at the maximum working pressure p2, the plunger cavity runs from the bottom dead center to connect with the low-pressure waist groove, in this process, the plunger cavity pressure drops from p2 to p1, and the required valve plate angle α3 can be deduced as follows: In the above formula, V d2 It is the volume of the plunger cavity when it is at the bottom dead center of the distribution plate.

10. The structural parameter matching design method of the axial piston pump "Shuttle" according to claim 9, characterized in that: The method belongs to the technical field of hydraulic transmission and hydraulic components.

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