Energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area

Abstract

The present invention provides an energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure region to a low-pressure region, which can not only balance the pressure difference at the moment of connection between the high-pressure region and the low-pressure region, but also effectively and controllably dissipate a part of the jet kinetic energy, so as to reduce the pressure pulsation and the noise of the fluid machinery. It is arranged on the main structure, and the main structure has a high-pressure region and a low-pressure region. This energy dissipation structure includes a flow channel arranged between the high-pressure region and the low-pressure region for the medium to flow between the high-pressure region and the low-pressure region, and an energy dissipation structure for blocking the medium and / or making the medium flow in the flow channel is provided in the flow channel. The present invention has the functions of balancing the pressure difference, reducing the pressure pulsation, and reducing the working noise.

Description

Technical Field

[0001] The present invention belongs to the technical field of fluid buffering devices, and particularly relates to an energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area. Background Art

[0002] When a fluid encounters an obstacle, vortices will be generated around the obstacle. When the fluid flows, it overcomes the internal friction force and the mutual collision and momentum exchange between fluid particles when overcoming turbulence, resulting in energy loss, which is manifested as a certain pressure drop. The resistance in the fluid channel can dissipate part of the kinetic energy of the fluid. Converting part of the fluid kinetic energy into heat helps to reduce the vibration and noise generated by the fluid kinetic energy in the fluid machinery. In fluid machinery that relies on fluid media (such as hydraulic pumps / motors / valves), there are high-pressure areas and low-pressure areas. Due to the presence of a certain amount of gas dissolved in the fluid medium or the existence of extremely small bubbles, the fluid medium exhibits slight compressibility. When the high-pressure area and the low-pressure area are connected, the fluid medium in the low-pressure area is compressed under the high pressure, and the fluid medium flows from the high-pressure area to the low-pressure area. Although the flow rate of the fluid medium is extremely small, a jet flow with a very high speed will be formed within an extremely short time (such as 1 millisecond). After the pressure is balanced, the jet flow ends.

[0003] For example, in a 9-piston axial piston pump, there are 9 piston holes on the cylinder block responsible for oil suction / discharge. When the rotational speed of the cylinder block is 1800 rpm, the cylinder block rotates 30 circles per minute. Any piston hole will move along the circumference, complete oil suction when passing through the low-pressure area of the valve plate, and then approach the high-pressure area. At the moment when the piston hole is connected to the high-pressure area, the above-mentioned jet flow is generated. After the pressure is balanced, the cylinder block continues to rotate to complete oil discharge. This process occurs 270 times per second. In the case of a high-pressure area of 35 MPa and a low-pressure area of 0.1 MPa, the jet flow speed can reach 250 m / sec to 300 m / sec. This jet flow causes pressure pulsation and induces the vibration of the entire fluid machinery, which is the main source of fluid machinery noise. In order to reduce noise, various structures are used to discharge the flow and balance the pressure at the moment of high-low pressure connection. Among them, grooves or holes are also used on the valve plate of the axial piston pump for flow discharge. However, these flow discharge structures are only narrow grooves and / or fine holes, which can play a role in balancing the pressure and cannot effectively dissipate the energy of the jet flow, so the effect is limited. The kinetic energy of the jet flow is manifested as vibration and noise spreading outward.

[0004] In order to solve the deficiencies existing in the prior art, people have carried out long-term explorations and put forward various solutions. For example, a Chinese patent document discloses an automotive water pump with a buffer chamber [201320194030.1], which includes a pump body. A pump inner cavity is provided in the pump body. A rotating shaft is provided in the pump inner cavity. A water seal device is sleeved on the rotating shaft. The water seal device isolates the pump inner cavity into a first and a second pump body cavity. The rotating shaft penetrates through the first and second pump body cavities. An impeller is provided in the first pump body cavity and is sleeved outside the rotating shaft. One end of the rotating shaft away from the first pump body cavity penetrates through the second pump body cavity to form a rotating shaft penetrating section. A pulley device is provided on the rotating shaft penetrating section. A fluid passage communicating with the first pump body cavity is provided on the pump body. A buffer chamber is provided on one side of the fluid passage close to the first pump body cavity. The inner diameter of the buffer chamber is larger than that of the fluid passage. The buffer chamber communicates with the first pump body cavity and the fluid passage.

[0005] The above solution solves the noise problem caused by excessive fluid flow to a certain extent through the buffer chamber, but there are still many deficiencies in this solution. For example, the fluid deceleration is not obvious and the energy dissipation effect is poor. Summary of the Invention

[0006] The object of the present invention is to provide an energy dissipation structure that is reasonably designed, has a simple structure, good energy dissipation effect, and can control the jet flow of a fluid medium from a high-pressure area to a low-pressure area in view of the above problems.

[0007] To achieve the above object, the present invention adopts the following technical solutions: The energy dissipation structure that can control the jet flow of a fluid medium from a high-pressure area to a low-pressure area is provided on a structure main body, and the structure main body includes a stationary high-pressure area and a low-pressure area that can move towards the high-pressure area. The high-pressure area is stationary, and the low-pressure area can approach the high-pressure area along a straight line, a circle, or a specific trajectory and will communicate at a certain position during operation. This structure includes a flow channel provided in the high-pressure area, and an energy dissipation structure for blocking the medium and / or dissipating the fluid energy when the medium flows in the flow channel is provided in the flow channel. When the low-pressure area moves to communicate with the high-pressure area, a jet flow is generated instantaneously due to the pressure difference, and the energy dissipation structure in the flow channel plays a role in dissipating the fluid energy. The flow channel reduces the impact of the jet flow and has a good noise reduction effect.

[0008] In the above energy dissipation structure that can control the jet flow of a fluid medium from a high-pressure area to a low-pressure area, the energy dissipation structure has a medium channel provided in the flow channel, and the medium channel is in any one or a combination of a curved shape, a folded-back shape, and a porous shape. The curved, folded-back, and porous medium channels can adapt to fluids with different viscosities and obtain the best blocking effect.

[0009] In the above energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area, the energy dissipation structure includes an energy dissipation cavity provided on the structure main body and communicating with the high-pressure area and the low-pressure area respectively. An energy dissipation component is arranged in the energy dissipation cavity, and a medium channel is formed in the energy dissipation component. When the fluid passes through the energy dissipation component, the fluid is blocked, and part of the fluid energy is dissipated, which can not only balance the pressure but also reduce the fluid noise.

[0010] In the above energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area, the energy dissipation component includes a plurality of sheet-like objects stacked in sequence from top to bottom in the energy dissipation cavity. A plurality of through holes are respectively formed in the sheet-like objects, and the through holes on two adjacent sheet-like objects are arranged in a staggered manner and communicate with each other, and the through holes on each sheet-like object are sequentially connected to form the above-mentioned medium channel. The sheet-like objects are stacked, and the size of the medium channel can be adjusted according to the stagger of the sheet-like objects, and the blocking effect on the fluid medium is controllable, so as to obtain different degrees of energy dissipation effects.

[0011] In the above energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area, the energy dissipation component includes a plurality of mesh-like objects stacked from top to bottom in the energy dissipation cavity, and the medium channel is formed in each mesh-like object. The mesh size of the mesh structure is adjustable, and the blocking effect on the fluid medium is controllable, so as to obtain different degrees of energy dissipation effects.

[0012] In the above energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area, the energy dissipation component includes a block filled in the energy dissipation cavity and composed of at least one porous material, and the medium channel is formed in the block. The porous block is installed in the energy dissipation cavity, and the hole size and density of the porous block are adjustable, and the blocking effect on the fluid medium is controllable, so as to obtain different degrees of energy dissipation effects.

[0013] In the above energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area, a through drain hole is opened at the bottom of the energy dissipation cavity, and a liquid collecting cavity is left between the bottom of the energy dissipation cavity and the energy dissipation component. The liquid collecting cavity is communicated with the drain hole. When the low-pressure cavity moves to a position communicating with the drain hole of the high-pressure area, the energy dissipation cavity is communicated with the low-pressure cavity. Due to the slight compressibility of the fluid medium, a small amount of fluid enters the liquid collecting cavity from the energy dissipation cavity and is discharged into the low-pressure cavity after being concentrated through the drain hole. The whole flow process takes an extremely short time. The fluid is blocked in the energy dissipation cavity, and part of the fluid energy is dissipated.

[0014] In the above energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area, a typical application is the valve plate of an axial piston pump. The main body of its structure includes a valve plate body, on which there are a number of oil discharge cavities and oil suction cavities arranged along a pitch circle of a certain radius relative to the center of the valve plate body. On one side of the valve plate body, there are communication grooves that connect the energy dissipation cavity with the oil discharge cavity and / or the oil suction cavity.

[0015] Compared with the existing technology, the advantages of the present invention are as follows: A flow channel composed of an energy dissipation structure is provided between the high-pressure area and the low-pressure area. This energy dissipation structure can block the instantaneous jet flow generated due to the pressure difference and fluid compressibility, dissipate part of the fluid kinetic energy, and effectively reduce the energy of the jet flow; The sheet-like objects are stacked, and curved, folded-back, and porous medium channels can be formed. The degree of stacking is controllable, so as to adapt to different fluids and obtain different degrees of energy dissipation effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the present invention;

[0017] Figure 2 is a schematic structural diagram of the high-pressure area of the present invention;

[0018] Figure 3 is Figure 2 a schematic structural diagram from another perspective;

[0019] Figure 4 is a schematic structural diagram of the internal cavity of the present invention;

[0020] Figure 5 is a sectional view of the installation structure of the sheet-like object of the present invention;

[0021] Figure 6 is a sectional view of the installation structure of the mesh-like object of the present invention;

[0022] Figure 7 is a sectional view of the installation structure of the block-like object of the present invention;

[0023] Figure 8 is a schematic structural diagram of the valve plate body in the specific application of the present invention;

[0024] Figure 9 is a sectional schematic structural diagram of the specific application of the present invention;

[0025] In the figures, the main body of the structure 1, the high-pressure area 11, the low-pressure area 12, the low-pressure cavity 13, the flow channel 2, the energy dissipation structure 3, the medium channel 31, the energy dissipation cavity 32, the energy dissipation assembly 4, the sheet-like object 41, the through hole 42, the mesh-like object 43, the block-like object 44, the drain hole 45, the liquid collecting cavity 46, the valve plate body 5, the oil suction cavity 51, the oil discharge cavity 52, the communication groove 53. DETAILED DESCRIPTION OF THE INVENTION

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0027] As Figures 1-9 shown, an energy dissipation structure for controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area is provided on a structure main body 1, and the structure main body 1 includes a stationary high-pressure area 11 and a low-pressure area 12 that can move along a straight line, a circumference or other trajectories towards the high-pressure area 11. This structure includes a flow channel 2 provided in the high-pressure area 11, and an energy dissipation structure 3 for blocking the medium and / or dissipating the fluid energy when the medium flows in the flow channel 2 is provided in the flow channel 2. When the low-pressure area 12 moves to communicate with the high-pressure area 11, a jet flow is generated instantaneously due to the pressure difference, and the energy dissipation structure 3 in the flow channel 2 plays a role in dissipating the fluid energy. After the fluid enters the structure main body 1, it passes through the flow channel 2 composed of the energy dissipation structure 3, and after the kinetic energy of the fluid is further consumed, it is transmitted to a liquid collection cavity 46 and then led out into a low-pressure cavity 13 of the low-pressure area 12, and the pressures of the high-pressure area 11 and the low-pressure area 12 are balanced.

[0028] Specifically, the energy dissipation structure 3 has a medium channel 31 provided in the flow channel 2, and the medium channel 31 is in any one or a combination of a curved shape, a folded-back shape, and a porous shape. Different fluids have different viscosities, and different shapes are formed in the medium channel 31 to block the fluid flow. When the fluid moves relative to the medium channel 31, corresponding resistance is received, thereby dissipating the kinetic energy of the fluid.

[0029] Further, the energy dissipation structure 3 includes an energy dissipation cavity 32 provided on the structure main body 1 and communicating with the high-pressure area 11 and the low-pressure cavity 13 respectively. An energy dissipation component 4 is arranged in the energy dissipation cavity 32, and the medium channel 31 is formed in the energy dissipation component 4. The energy dissipation component 4 in the energy dissipation cavity 32 plays a main blocking role. After the fluid enters the energy dissipation cavity 32, part of the fluid kinetic energy is dissipated under the resistance of the energy dissipation component 4.

[0030] Furthermore, the energy dissipation component 4 includes a plurality of sheet-like objects 41 stacked on top of each other in sequence from top to bottom in the energy dissipation cavity 32. A plurality of through holes 42 are respectively formed in the sheet-like objects 41, and the through holes 42 on two adjacent sheet-like objects 41 are arranged in a staggered manner and communicate with each other, and the through holes 42 on each sheet-like object 41 are sequentially connected to form the above-mentioned medium channel 31. The energy dissipation component 4 formed by stacking the sheet-like objects 41 blocks layer by layer when the fluid flows from the high-pressure area 11 to the low-pressure area 12, and the degree of staggering of the sheet-like objects 41 therein can be freely adjusted, and its blocking effect on the fluid is controllable, so as to form different states of the medium channel 31 and obtain different energy dissipation effects.

[0031] In addition, the energy dissipation component 4 includes a plurality of meshes 43 stacked from top to bottom in the energy dissipation cavity 32, and the medium channels 31 are formed on each of the meshes 43. When the meshes 43 are used to form the energy dissipation component 4, the sizes of the densely distributed mesh holes on the meshes 43 are adjustable, and the blocking effect on the fluid medium is controllable, so as to obtain buffering effects of different degrees.

[0032] Meanwhile, the energy dissipation component 4 includes a block 44 filled in the energy dissipation cavity 32 and composed of at least one porous material, and the medium channels 31 are formed on the block 44. The medium channels 31 in the block 44 communicate with each other. During installation, the block 44 is directly clamped into the energy dissipation cavity 32. The porosity of the porous material is adjustable, and the blocking effect on the fluid medium is controllable, so as to obtain buffering effects of different degrees.

[0033] Obviously, a through drain hole 45 is formed at the bottom of the energy dissipation cavity 32, and a liquid collecting cavity 46 is left between the bottom of the energy dissipation cavity 32 and the energy dissipation component 4. The liquid collecting cavity 46 is communicated with the drain hole 45, and the drain hole 45 is opposite to the low-pressure area 12 provided on the structural body 1. The liquid collecting cavity 46 is connected to the low-pressure area 12. After the fluid passes through the energy dissipation cavity 32 and is concentrated in the liquid collecting cavity 46 for pressure stabilization, it is discharged from the drain hole 14 at the bottom into the low-pressure cavity 13 in the low-pressure area 12.

[0034] Preferably, the structural body 1 includes a flow distribution disk body 5. A plurality of oil suction cavities 51 and oil discharge cavities 52 are formed on the flow distribution disk body 5 and arranged along a pitch circle of a certain radius relative to the center of the flow distribution disk body 5. A communication groove 53 for communicating the energy dissipation cavity 32 with the oil suction cavity 51 and / or the oil discharge cavity 52 is formed on one side of the flow distribution disk body 5. The fluid in the oil discharge cavity 52 enters the energy dissipation cavity 32 through the communication groove 53. When the low-pressure cavity 13 (i.e., the cylinder bore) rotates to communicate with the drain hole 45, the high-pressure fluid flows from the drain hole 45 into the low-pressure cavity 13. Due to the blockage of the energy dissipation structure 32, part of the jet energy is dissipated.

[0035] A typical application of the energy dissipation structure 3 of the present invention is the valve plate of an axial piston pump. Specifically, the structural body 1 is the valve plate body 5, and the valve plate body 5 is stationary. The oil discharge cavity 52 on the valve plate body 5 is at high pressure. The cylinder block rotates. The cylinder block is distributed with plunger holes for oil suction / discharge. Along with the rotational movement, the plunger holes are always in communication with the oil suction cavity 51 during the oil suction process, and the oil suction cavity 51 is at low pressure. After the oil is fully sucked, the oil suction cavity 51 continues to approach the oil discharge cavity 52. When the cylinder block rotates to a certain position, the oil suction cavity 51 is in communication with the energy dissipation cavity 32. Since air is dissolved in the hydraulic oil or there are minute air bubbles, the hydraulic oil exhibits compressibility. Due to the high and low pressure difference, an instantaneous jet flow is caused from the high-pressure oil discharge cavity 52 to the low-pressure oil suction cavity 51. When the jet flow occurs, the energy dissipation component 4 plays a role. Due to the blockage of the energy dissipation component 4, a pressure drop is formed within the energy dissipation component 4, and part of the jet flow kinetic energy is dissipated, forming heat energy, reducing the vibration and noise generated by the impact of the jet flow kinetic energy. Since the compressibility of the hydraulic oil is usually 0.0006 - 0.0009 / MPa, the flow rate of the jet flow is extremely small. When the rotational speed is 1800 rpm, the rotational speed of the cylinder block is 30 revolutions per second, and the jet flow process is approximately about 1 millisecond. After the jet flow ends, the pressures in the high and low pressure cavities are balanced. Specifically, when the number of plunger holes on the cylinder block is 9, 270 jet flows occur per second, and the impact kinetic energy of the jet flow will cause pressure pulsation, which is the main reason for exciting noise. The energy dissipation structure 3 of the present invention can effectively reduce the fluid kinetic energy that excites noise.

[0036] In summary, the principle of this embodiment is as follows: An energy dissipation structure 3 is provided between the high-pressure area 11 existing on the structural body 1 and the drain hole 45. An energy dissipation component 4 is provided within the energy dissipation structure 3. The energy dissipation component 4 has a sheet-like object 41 or a mesh-like object 43 or a block-like object 44, forming a complex medium channel 31. When the low-pressure area 12 moves towards the high-pressure area 11, the two are not in communication. When reaching a certain position, the high-pressure area 11 is in communication with the low-pressure area 12. Since air is dissolved in the fluid medium or there are minute air bubbles, the fluid medium exhibits compressibility. Under the action of the high and low pressure difference, a minute jet flow is formed from the oil discharge cavity 52 to the oil suction cavity 51. The energy dissipation structure 3 blocks the fluid, generating complex eddy currents, causing a pressure drop, dissipating part of the kinetic energy of the jet flow, and converting it into heat energy, thereby reducing the impact of the jet flow and reducing vibration and noise.

[0037] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the technical field to which the present invention pertains can make various modifications or supplements to the described specific embodiments or use similar ways to substitute, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0038] Although terms such as structural body 1, high-pressure area 11, low-pressure area 12, low-pressure cavity 13, flow channel 2, energy dissipation structure 3, medium channel 31, energy dissipation cavity 32, energy dissipation component 4, sheet 41, through hole 42, mesh 43, block 44, drain hole 45, liquid collection cavity 46, flow distribution disk body 5, oil suction cavity 51, oil discharge cavity 52, and communication groove 53 are used more frequently in this text, the possibility of using other terms is not excluded. Moreover, the fluid medium in the plunger pump is not limited to oil and may also be other fluids such as water and water glycol. The use of these terms is only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitation is contrary to the spirit of the present invention.

Claims

1. An energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area, which is arranged on a structure main body (1), and the structure main body (1) includes a stationary high-pressure area (11) and a low-pressure area (12) capable of moving towards the high-pressure area (11). Characterized in that the structure main body (1) includes a flow channel (2) arranged in the high-pressure area (11), and an energy dissipation structure (3) for blocking the medium is arranged in the flow channel (2). When the low-pressure area (12) moves to communicate with the high-pressure area (11), a jet flow is generated instantaneously due to the pressure difference, and the energy dissipation structure (3) in the flow channel (2) plays a role in dissipating the fluid energy; the energy dissipation structure (3) has a medium channel (31) arranged in the flow channel (2), and the medium channel (31) is in any one or a combination of a curved shape, a folded shape, and a porous shape; the energy dissipation structure (3) includes an energy dissipation cavity (32) arranged on the structure main body (1) and communicating with the high-pressure area (11) and the low-pressure area (12) respectively. An energy dissipation component (4) is arranged in the energy dissipation cavity (32), and the medium channel (31) is formed in the energy dissipation component (4); the energy dissipation component (4) includes a plurality of sheet-like objects (41) stacked in sequence from top to bottom in the energy dissipation cavity (32). A plurality of through holes (42) are respectively formed in the sheet-like objects (41), and the through holes (42) on two adjacent sheet-like objects (41) are arranged in a staggered manner and communicate with each other, and the through holes (42) on each sheet-like object (41) are sequentially connected to form the above-mentioned medium channel (31); a through drain hole (45) is formed at the bottom of the energy dissipation cavity (32), and a liquid collection cavity (46) is left between the bottom of the energy dissipation cavity (32) and the energy dissipation component (4). The liquid collection cavity (46) communicates with the drain hole (45), and the drain hole (45) faces a low-pressure cavity (13) arranged on the low-pressure area (12); the structure main body (1) includes a flow distribution disk body (5), and a plurality of oil suction cavities (51) and oil discharge cavities (52) are arranged on the flow distribution disk body (5) along a pitch circle of a certain radius relative to the center of the flow distribution disk body (5). A communication groove (53) for communicating the energy dissipation cavity (32) with the oil suction cavity (51) and / or the oil discharge cavity (52) is formed on one side of the flow distribution disk body (5).

2. The energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area according to claim 1, Characterized in that the energy dissipation component (4) is replaced with: including a plurality of mesh-like objects (43) stacked from top to bottom in the energy dissipation cavity (32), and the medium channel (31) is formed on each mesh-like object (43).

3. The energy dissipation structure capable of controlling the jet flow of a fluid medium from a high-pressure area to a low-pressure area according to claim 1, Characterized in that The described energy dissipation component (4) is replaced with: including a block (44) filled in the energy dissipation cavity (32) and composed of at least one porous material, and the medium channel (31) is formed on the block (44).

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