Low-pulsation low-noise axial plunger pump device

Abstract

The invention discloses a low-pulsation low-noise axial plunger pump device which comprises a shell, an oil distribution cover, a main shaft arranged in the middle in the shell, a plurality of plungers distributed in a back-to-back staggered mode along the circumference of the main shaft, an oil distribution disc located in the shell and arranged at the end of the main shaft, a floating cylinder base located on the rear side of the oil distribution disc, a floating cylinder and a limiting sleeve. A pressing plate is arranged between the floating cylinder and the plunger; and a driving pin is arranged between the floating cylinder seat and the main shaft. The number of the plungers is 2-3 times that of a conventional pump, the plungers are back to back and staggered, hydraulic pressure internal force borne by the main shaft can be counteracted, work and operation are stable, the generated pulsation double amplitude is very low, and compared with a traditional plunger pump, the pump is few in leakage point and high in volume efficiency; high-quality flow can be output, and noise is low. The invention has the advantages of simple structure, small occupied space, light weight, lower pressure pulsation and low noise.

Description

Technical Field

[0001] The invention relates to the technical field of volumetric hydraulic pumps, in particular to an axial piston pump device with low pulsation and low noise. Background Art

[0002] With the development of science and technology, whether it is the aviation field, engineering machinery field or marine hydraulic pump, the main engine users have higher and higher requirements on the performance and quality of hydraulic pumps. In hydraulic transmission, the hydraulic pump, as the power source of the hydraulic system, is equivalent to the "heart" of the hydraulic system. Its performance and reliability largely determine the performance of the entire hydraulic system.

[0003] There is inevitably fluid resistance inside the pump or in the system pipeline. High flow pulsation will inevitably cause large pressure pulsation. When the pulsation frequency is equivalent to the natural frequency of the hydraulic oil column and the pipeline, a resonance condition is created. During resonance, the pressure pulsation may be extremely high, which is potentially destructive to the construction of the system. In some extreme cases, the pipeline or accessories can reach the fatigue damage limit within a few minutes. The flow and pressure pulsation of the hydraulic oil excites high-frequency mechanical vibrations in the pipeline or accessories, which will cause stress that damages the pipeline, accessories and installation components. As mentioned above, the pressure pulsation of the hydraulic pump is particularly important for the hydraulic equipment system.

[0004] When designing hydraulic pumps and hydraulic systems, full consideration should be given to taking measures to suppress or absorb pressure pulsation to avoid resonance. For the double amplitude of pressure pulsation, relevant standards have regulations. With the requirements of miniaturization and lightweight of hydraulic systems, hydraulic systems will inevitably develop in the direction of high pressure, and high-pressure systems will inevitably lead to increased vibration and noise. Reducing the pressure pulsation of hydraulic pumps is a trend in the development of hydraulic technology.

[0005] Currently, the existing high-pressure pumps, whether radial piston pumps or axial piston pumps, have little room for optimization of pressure pulsation in terms of structural design. This is determined by the inherent structural characteristics of the existing piston pumps.

[0006] Therefore, it is of great significance to design a plunger pump device with simple structure, small space occupation, light weight, low pressure pulsation and low noise. Summary of the invention

[0007] The object of the present invention is to provide an axial piston pump device with low pulsation and low noise. The present invention has the advantages of simple structure, small occupied space, light weight, low pressure pulsation and low noise.

[0008] The technical solution of the present invention is: a low-pulsation and low-noise axial piston pump device, including a housing, an oil separator cover, a main shaft arranged in the middle of the housing, a plurality of plungers staggered and distributed back to back along the circumference of the main shaft, an oil separator plate located in the housing and arranged at the end of the main shaft, a float cylinder seat located at the rear side of the oil separator plate, a float cylinder and a limit sleeve; a pressure plate is provided between the float cylinder and the plunger; a drive pin is provided between the float cylinder seat and the main shaft.

[0009] In the aforementioned low-pulsation and low-noise axial piston pump device, the number of the pistons is 2n, where n≥12; and the working end of each of the pistons is drum-shaped.

[0010] In the aforementioned low-pulsation and low-noise axial piston pump device, the main shaft includes a wheel disc in the middle and drum-shaped spheres distributed on both sides of the wheel disc; each of the drum-shaped spheres has a circle of 6 pin holes distributed circumferentially on the circumference; each of the pin holes is perpendicular to the main shaft and passes through the center of the sphere.

[0011] In the aforementioned low-pulsation and low-noise axial piston pump device, each of the floating cylinder seats is provided with a cylinder seat groove, and the cylinder seat groove is a rectangular groove; the driving pin can slide along the cylinder seat groove.

[0012] In the aforementioned low-pulsation and low-noise axial piston pump device, a ball hinge disc, a butterfly spring and a retaining ring are sequentially arranged between the drum-shaped ball and the floating cylinder seat.

[0013] In the aforementioned low-pulsation and low-noise axial piston pump device, the working surface of the oil separation plate 1 is an inclined surface.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The plungers are installed back to back and staggered along the circumference of the wheel disc of the main shaft; there are many plungers, and the back-to-back design offsets each other's internal forces, resulting in very low double amplitude of pressure pulsation, thereby outputting high-quality flow, and the noise generated by this structure is lower than that of traditional plunger pumps;

[0016] 2. Compared with the traditional hydraulic pump, the plunger hole carrier adopts a floating cylinder structure. The free floating of the floating cylinder can automatically compensate for the displacement difference caused by the elliptical trajectory of the floating cylinder and the accumulated tolerance caused by the parts processing. At the same time, the floating cylinder adopts the traditional static hydraulic support residual clamping force design method, so that a good seal is achieved between the floating cylinder and the floating cylinder seat, ensuring the volumetric efficiency of the plunger pump;

[0017] 3. This application adds a limit pressure plate for pump working conditions to limit the end face of the floating cylinder, solving the problem of insufficient inlet oil suction when used as a pump. It not only meets the working conditions of the motor, but also meets the requirements of the pump working conditions.

[0018] In summary, the present application improves the working stability of the hydraulic system on the basis of ensuring the compact structure and lightweight of the axial piston pump, effectively prolongs the service life of the system and components, has a simple structure, occupies a small space, is lightest, is not limited by the installation space of the host, and has the advantages of easy installation and high maintainability.

[0019] Since the number of plungers is 2 to 3 times that of conventional pumps, and they are back-to-back and offset from each other, the internal forces of the hydraulic pressure acting on the main shaft can offset each other, the operation is stable, and the double amplitude of the pulsation generated is very low. Moreover, compared with traditional plunger pumps, this pump has fewer leakage points and higher volumetric efficiency; it can output high-quality flow and low noise.

[0020] Therefore, the present invention has the advantages of simple structure, small occupied space, light weight, low pressure pulsation and low noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The structure of the present invention is schematically shown Figure 1 ;

[0022] Figure 2 yes Figure 1 Schematic diagram of the MM structure;

[0023] Figure 3 yes Figure 2 Enlarged view of point A in the middle;

[0024] Figure 4 It is a structural schematic diagram of the floating cylinder seat of the present invention;

[0025] Figure 5 It is a schematic diagram of the distribution of the main shaft and the plunger of the present invention;

[0026] Figure 6 It is a schematic diagram of the pressing plate structure of the present invention.

[0027] Markings in the accompanying drawings: 1-oil distribution plate, 2-floating cylinder seat, 201-cylinder seat groove, 3-limiting sleeve, 4-floating cylinder, 5-pressure plate, 6-plunger, 7-spindle, 701-pin hole, 702-wheel plate, 8-oil distribution cover, 9-driving pin, 10-housing, 11-ball hinge plate, 12-butterfly spring, 13-retaining ring, 14-locating pin. DETAILED DESCRIPTION

[0028] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0029] Embodiment. A low-pulsation and low-noise axial piston pump device, such as Figure 1-6As shown, it includes a shell 10, an oil separator cover 8, a main shaft 7 arranged in the middle of the shell 10, a plurality of plungers 6 distributed back to back and staggered along the circumference of the main shaft 7, an oil separator plate 1 located in the shell 10 and arranged at the end of the main shaft 7, a floating cylinder seat 2 located at the rear side of the oil separator plate 1, a floating cylinder 4 and a limiting sleeve 3; a pressure plate 5 is provided between the floating cylinder 4 and the plunger 6; a driving pin 9 is provided between the floating cylinder seat 2 and the main shaft 7.

[0030] The number of the plungers 6 is 24; the working end of each plunger 6 is drum-shaped.

[0031] like Figure 5 As shown, the main shaft 7 includes a wheel disc 702 in the middle and drum-shaped spheres distributed on both sides of the wheel disc 702; each of the drum-shaped spheres has a circle of 6 pin holes 701 distributed circumferentially on the circumference; each of the pin holes 701 is perpendicular to the main shaft 7 and passes through the center of the sphere.

[0032] like Figure 5 The plunger 6 is divided into two parts, 12 pieces are loaded on the left side of the wheel disc 702, and 12 pieces are loaded on the right side, and they are fixed to the main shaft 7 with fastening screws. The arrangement of the columns 6 is arranged side by side and staggered along the circumference, and the left plunger 6 and the right plunger 6 are staggered by 15°.

[0033] Each of the floating cylinder seats 2 is provided with a cylinder seat groove 201, and the cylinder seat groove 201 is a rectangular groove; the driving pin 9 can slide along the cylinder seat groove 201 to ensure that the floating cylinder seat 2 is in close contact with the working surface of the oil distribution plate.

[0034] The driving pin 9 is inserted between the pin hole 701 and the cylinder seat groove 201 respectively. When the main shaft 7 rotates, the driving pin 9 rotates with the main shaft 7 to drive the floating cylinder seat 2, so that the floating cylinder seat 2 and the main shaft 7 rotate synchronously.

[0035] A ball hinge plate 11, a butterfly spring 12 and a retaining ring 13 are arranged in sequence between the drum-shaped ball and the floating cylinder seat 2. The butterfly spring 12 is designed to provide preload force, so that the floating cylinder seat 2 and the oil distribution plate 1 are in flexible contact, and the product has a higher volumetric efficiency regardless of high or low pressure.

[0036] The working surface of the oil separation plate 1 is an inclined surface.

[0037] A positioning pin 14 is further provided in the housing 10 . The positioning pin 14 is located between the oil separator 1 and the housing 10 , and is used to accurately orient the oil separator 1 and determine the upper and lower dead points of the oil separator 1 .

[0038] Working principle:

[0039] like Figure 1The present invention adopts a symmetrical design. When the main shaft 7 rotates, since the working surface of the oil separator 1 is designed as an inclined surface (the oil separator 1 not only has the diversion function of high and low pressure oil, but also satisfies the inclination function of the inclined plate), the plunger volume cavity is forced to increase and the hydraulic oil is sucked in. The oil can pass through the housing 10 and the oil separator cover 8 through the floating cylinder seat 2 and enter the plunger holes on both sides at the same time. As the main shaft 7 and the floating cylinder seat 2 rotate, the hydraulic oil passes the top dead center, and the plunger cavity volume continues to decrease. After loading the B port, the outlet high-pressure oil is formed; the working end of the plunger 6 adopts a drum-shaped design, so that the plunger 6 is in line contact with the floating cylinder 4. Since the running trajectory of the floating cylinder 4 is an ellipse, the drum-shaped line contact design ensures that the floating cylinder 4 is close to the floating cylinder seat 2 and runs smoothly; when the main shaft 7 rotates, the various components cooperate with each other to complete the oil suction and discharge process of the plunger pump in an orderly manner.

[0040] As shown in Fig. 3, under the premise of the design of the gap δ1, the floating cylinder 4 can realize a certain free displacement movement within a range of 360° around the limit sleeve 3, and the movement trajectory of the floating cylinder 4 is elliptical. The gap δ1 not only compensates for the displacement difference caused by the elliptical trajectory, but also corrects the inevitable cumulative tolerance of the components; the floating cylinder 4 and the floating cylinder seat 2 are designed as traditional static pressure supports, which must ensure that the floating cylinder slides on the plane of the floating cylinder seat 2, and the floating cylinder 4 cannot be separated from the floating cylinder seat 2, so a gap δ2 is set, and the gap δ2 = Hh.

Claims

1. A low-pulsation and low-noise axial piston pump device, characterized in that: The invention comprises a housing (10), an oil separator cover (8), a main shaft (7) arranged in the middle of the housing (10), a plurality of plungers (6) arranged in a back-to-back staggered manner along the circumference of the main shaft (7), an oil separator plate (1) located in the housing (10) and arranged at the end of the main shaft (7), a floating cylinder seat (2) located at the rear side of the oil separator plate (1), a floating cylinder (4) and a limiting sleeve (3); a pressure plate (5) is arranged between the floating cylinder (4) and the plunger (6); and a driving pin (9) is arranged between the floating cylinder seat (2) and the main shaft (7).

2. The low-pulsation and low-noise axial piston pump device according to claim 1, characterized in that: The number of the plungers (6) is 2n, where n≥12; the working end of each plunger (6) is drum-shaped.

3. The low-pulsation and low-noise axial piston pump device according to claim 1, characterized in that: The main shaft (7) comprises a wheel disc (702) in the middle and drum-shaped spheres distributed on both sides of the wheel disc (702); each drum-shaped sphere has a circle of 6 pin holes (701) distributed circumferentially on the circumference; each pin hole (701) is perpendicular to the main shaft (7) and passes through the center of the sphere.

4. The low-pulsation and low-noise axial piston pump device according to claim 1, characterized in that: Each of the floating cylinder seats (2) is provided with a cylinder seat groove (201), and the cylinder seat groove (201) is a rectangular groove; the driving pin (9) can slide along the cylinder seat groove (201).

5. The low-pulsation and low-noise axial piston pump device according to claim 3, characterized in that: A ball hinge disc (11), a butterfly spring (12) and a retaining ring (13) are arranged in sequence between the drum-shaped sphere and the floating cylinder seat (2).

6. The low-pulsation and low-noise axial piston pump device according to claim 1, characterized in that: The working surface of the oil separation plate (1) is an inclined surface.

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