Self-cooling integrated wet-type motor pump

Abstract

The invention provides a self-cooling integrated wet-type motor pump which is composed of a pump assembly, a motor assembly, a motor pump shell and other parts, cooling holes are formed in a swash plate assembly of the pump assembly and the motor pump shell, and the cooling holes are located on the movement track line of a sliding shoe. The high-pressure plunger cavity injects high-pressure oil in the high-pressure plunger cavity into the motor assembly through the cooling hole, the oil is sucked back through the low-pressure plunger cavity, the motor assembly is cooled in the oil suction and discharge process, and due to the fact that the flow of a cooling medium depends on the pressure in the plunger, when the load of the motor pump is large, the pressure in the plunger is high, the cooling flow is large, and the motor assembly is cooled. And a self-adaptive cooling structure changing along with the load is formed. Compared with a traditional wet-type oil-immersed motor pump, the heat exchange efficiency of the motor pump is greatly improved through circular flowing of the cooling medium, and the heat dissipation capacity of the motor is improved.

Description

Technical Field

[0001] The present invention relates to the field of motor pumps, and particularly to a self-cooling integrated wet motor pump. Background Art

[0002] As an energy component of a hydraulic system, a motor pump is the core of the hydraulic system. In recent years, the wide application of electro-hydrostatic servo mechanisms has greatly promoted the development of servo motor pumps. The motor pump has gradually evolved from the traditional form of motor + pump to the coaxial integrated form of motor pump, and the dynamic seal at the end of the pump shaft has been cancelled, enabling the oil to enter the motor to cool the motor, and the motor has changed from dry type to wet type. However, at present, most motor pumps are oil-immersed motors. After the oil heats up while cooling the motor, it is difficult to be discharged from the motor cavity in time, resulting in poor heat dissipation effect. Although some motor pumps adopt a circulating oil circuit, their cooling flow rate is a fixed value and cannot be adjusted according to the load change. When the load of the motor pump is small, the cooling flow rate is still too large, causing energy loss. Therefore, it is necessary to optimize the cooling structure of the motor pump to achieve more efficient cooling. Summary of the Invention

[0003] The purpose of the present invention is to provide a self-cooling integrated wet motor pump to solve the problems existing in the prior art.

[0004] The technical solution of the present invention is: to provide a self-cooling integrated wet motor pump, including a motor assembly and a piston pump assembly. The motor assembly and the piston pump assembly share a motor pump housing and a motor pump shaft; the motor pump housing and the motor pump shaft divide the interior of the motor pump into a motor cavity and a piston pump cavity; the piston pump is composed of a swash plate seat, a swash plate, a cylinder block, a low-pressure slipper, a low-pressure piston, a valve plate, a high-pressure slipper, and a high-pressure piston;

[0005] There are two pairs of cooling holes on the swash plate, namely an oil discharge cooling hole and an oil suction cooling hole. At the same time, there is also a pin slot on the swash plate;

[0006] There are 2 cooling channels and a pin hole on the swash plate seat. The swash plate is matched with the swash plate seat through a pin. The cooling channel is composed of an elliptical arc-shaped cooling groove and a cooling hole. The first cooling groove of the swash plate seat and the first cooling hole of the swash plate seat form a cooling channel, and the second cooling groove of the swash plate seat and the second cooling hole of the swash plate seat form a second cooling channel; the first cooling hole on the swash plate corresponds to the first cooling groove on the swash plate seat, and the second cooling hole corresponds to the second cooling groove on the swash plate seat;

[0007] When the high-pressure slipper passes through the second cooling hole on the swash plate, the high-pressure oil in the plunger and the cylinder block flows into the second cooling hole of the swash plate through the channels in the plunger and the slipper in sequence, and then flows into the motor pump housing through the second cooling groove and the second cooling hole on the swash plate seat, and flows into the motor cavity through the second cooling hole on the motor pump housing, so as to cool the motor assembly. That is, as the motor pump rotates, the cooling flow will intermittently inject into the motor cavity as the high-pressure slipper passes through the cooling hole on the swash plate.

[0008] Further, when the low-pressure slipper passes through the first cooling hole on the swash plate, the pressure of the low-pressure oil in the plunger and the cylinder block is lower than that in the motor cavity. At this time, the oil flows into the low-pressure slipper and the plunger through the first cooling hole of the motor pump housing, the first cooling hole of the swash plate seat, the first cooling groove and the first cooling hole on the swash plate in sequence. That is, as the motor pump rotates, the cooling flow will intermittently flow out of the motor cavity as the low-pressure slipper passes through the cooling hole on the swash plate; the above-mentioned flow direction of the cooling flow constitutes a circulating cooling channel.

[0009] Further, when the low-pressure slipper does not pass through the swash plate, the circulating cooling channel is not opened. At this time, the cooling flow flows into or into the motor cavity through the annular gap between the motor pump shaft and the motor pump housing, thus avoiding the phenomena of pressure buildup and cavitation that may occur when only one side of the slipper flows through the cooling hole.

[0010] The beneficial effects obtained by the self-cooling integrated wet motor pump provided by the present invention are as follows:

[0011] 1) Through the circulating flow of the cooling medium, the heat exchange efficiency of the motor pump is greatly improved compared with the traditional wet oil-immersed motor pump, and the heat dissipation capacity of the motor is improved.

[0012] 2) The cooling flow can change with the load size. When the load is large and the heat generation is high, the cooling flow is large; when the load is small and the heat generation is low, the cooling flow is small, reducing the ineffective internal leakage of the motor pump.

[0013] 3) The cooling structure of this motor pump is simple and can be applied to bidirectional motor pumps, having a relatively broad application prospect in aerospace EHA. Brief Description of the Drawings

[0014] The present invention will be further described below with reference to the drawings:

[0015] Figure 1 is a schematic structural diagram of a self-cooling integrated wet motor pump;

[0016] Figure 2 is a structural diagram of the swash plate in the self-cooling motor pump;

[0017] Figure 3 is a structural diagram of the swash plate seat in the self-cooling motor pump;

[0018] Figure 4 It is a sectional view of the swash plate seat along the cooling flow path in the self-cooling motor pump;

[0019] Figure 5 It is a schematic diagram of the plunger pump assembly in the self-cooling motor pump;

[0020] Figure 6 It is a schematic diagram of the cooling oil circuit direction in the self-cooling motor pump.

[0021] Wherein: A is the motor assembly, B is the plunger pump assembly, 1 is the swash plate seat, 2 is the swash plate, 3 is the cylinder block, 4 is the slipper (low pressure), 5 is the plunger (low pressure), 6 is the valve plate, 7 is the slipper (high pressure), 8 is the plunger (high pressure), 9 is the motor pump housing, 10 is the motor pump shaft, 201 is the cooling hole 1, 202 is the cooling hole 2, 203 is the pin slot, 101 is the swash plate seat cooling groove 1, 102 is the swash plate seat cooling groove 2, 105 is the pin hole, 103 is the swash plate seat cooling hole 1, 104 is the swash plate seat cooling hole 2, 11 is the low-pressure chamber, 12 is the high-pressure chamber, 601 is the high-pressure valve plate window, 602 is the low-pressure valve plate window, 901 is the motor pump housing cooling hole 1, 902 is the motor pump cooling hole 2, 903 is the annular gap. Specific embodiments

[0022] The following further elaborates on the self-cooling integrated wet motor pump proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description and claims, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise ratios, only for the purpose of conveniently and clearly assisting in explaining the purpose of the embodiments of the present invention.

[0023] Aiming at the deficiencies of the prior art, the present invention proposes a self-cooling integrated wet motor pump. The motor pump drives the oil to enter the motor cavity through the pressure difference between the high-pressure plunger cavity and the motor cavity of the motor pump plunger assembly to cool the motor, and then flows out of the motor cavity under the pressure difference between the motor cavity and the low-pressure plunger cavity and the oil return cavity of the pump, forming a circulating flow, greatly improving the cooling efficiency of the motor pump. At the same time, this cooling structure can make the cooling flow increase with the increase of the motor torque, and has the characteristic of self-adaptive adjustment of the cooling flow. Compared with the traditional wet motor pump, the structure is simple and more efficient, and has broad application prospects in aerospace.

[0024] The technical solution adopted by the present invention is as follows: a self-cooling integrated wet motor pump, the magnitude of whose cooling flow rate can automatically vary with the load. The greater the load of the motor pump, the greater the cooling flow rate. It consists of a plunger pump assembly with cooling holes, a motor pump housing with a cooling flow path, a motor assembly and other parts. The self-adaptive cooling motor pump housing divides the motor pump into a motor chamber and a pump chamber. The swash plate assembly of the plunger pump with cooling holes is composed of a swash plate seat and a swash plate. The swash plate is provided with cooling holes, and the swash plate seat is provided with two cooling flow paths, which are respectively composed of an elliptical cooling groove and a cooling hole. The cooling holes on the swash plate are at least two, and are divided into oil discharge cooling holes and oil suction cooling holes, which are generally distributed in pairs, and are respectively distributed in the oil suction side area and the oil discharge side area of the corresponding distribution plate, and are on the track line of the slipper. Multiple pairs of cooling holes can be provided on the swash plate, or the cooling flow rate under a given pressure difference can be increased by increasing the diameter of the cooling holes. When the plunger pump rotates, the high-pressure plunger chamber injects the internal high-pressure oil through the cooling holes into the motor assembly, and sucks the oil back through the low-pressure plunger chamber, and cools the motor assembly through the oil suction and discharge process, that is, the cooling flow direction is the high-pressure plunger chamber, the slipper, the swash plate oil discharge cooling hole, the swash plate seat oil discharge cooling hole, the motor pump housing cooling hole, the motor pump chamber, the motor pump housing cooling hole, the swash plate seat oil suction cooling hole, the swash plate oil suction cooling hole, the slipper, the low-pressure plunger chamber. In addition, there is also a fitting clearance between the motor pump shaft and the pump housing, which plays a balancing role when the pump plunger assembly does not pass through the cooling holes, avoiding phenomena such as pressure buildup and air suction.

[0025] Embodiment 1

[0026] Figure 1 It is a structural schematic diagram of a self-cooling integrated wet motor pump. The self-cooling motor pump consists of a motor assembly A and a plunger pump assembly B, and the two share a motor pump housing 9 and a motor pump shaft 10. The housing 9 and the motor pump shaft 10 divide the interior of the motor pump into a motor chamber and a plunger pump chamber. The plunger pump mainly consists of parts such as a swash plate seat 1, a swash plate 2, a cylinder block 3, a slipper (low pressure) 4, a plunger (low pressure) 5, a distribution plate 6, a slipper (high pressure) 7, and a plunger (high pressure) 8. Figure 2 It is a structural diagram of the swash plate in the self-cooling motor pump. There are two pairs of cooling holes 201 and 202 on the swash plate, which are respectively oil discharge cooling holes and oil suction cooling holes. In addition, there is also a pin slot 203 on the swash plate. Figure 3 and Figure 4They are respectively the structure diagram of the swash plate seat in the self-cooling motor pump and the sectional view of the swash plate seat along the cooling flow path. As can be seen from the figure, the swash plate seat is provided with two cooling flow paths and a pin hole 105. The swash plate 2 is matched with the swash plate seat 1 through a pin. The cooling flow path is composed of an elliptical arc-shaped (seen from the plane perpendicular to the mating surface of the swash plate seat and the swash plate) cooling groove and cooling holes. The swash plate seat cooling groove 1 (101) and the swash plate seat cooling hole 1 (103) form a cooling flow path, and the swash plate seat cooling groove 2 (102) and the swash plate seat cooling hole 2 (104) form the second cooling flow path. The cooling hole 201 on the swash plate corresponds to the cooling groove 101 on the swash plate seat, and the cooling hole 202 corresponds to the cooling groove 102 on the swash plate seat. Figure 5 It is a schematic diagram of the plunger pump assembly in the self-cooling motor pump. As shown in the figure, the cooling holes on the swash plate 2 are respectively distributed in the areas of the high-pressure distribution window 601 and the low-pressure distribution window 602 of the corresponding distribution disk 6. The three pairs of cooling holes are all on the track line of the slipper. The distribution disk 6 and the swash plate 2 are relatively fixed in the motor pump. The cylinder block 3 and the plunger and slipper inside it rotate with the rotation of the motor pump shaft 10. When the plunger and slipper rotate to the area corresponding to the high-pressure distribution window, the high-pressure plunger 8 and the high-pressure slipper 7 are formed. When the plunger and slipper rotate to the area corresponding to the low-pressure distribution window, the low-pressure distribution window 5 and the distribution slipper 4 are formed. Figure 6It is a schematic diagram of the cooling oil circuit of a self-cooling motor pump. When the slipper 7 passes through the cooling hole 202 on the swash plate 1, the high-pressure chamber 12 oil in the plunger 8 and the cylinder block 3 will flow into the cooling hole 202 of the swash plate through the channels in the plunger and the channels in the slipper in sequence. (It should be noted here that in order to form a lubricating support oil film between the slipper and the swash plate, there are usually flow holes on the plunger and the slipper of a general piston pump. Therefore, the flow holes in the slipper and the plunger are not the claim items of this patent), and then it flows into the motor pump housing 9 through the cooling groove 102 and the cooling hole 104 on the swash plate seat, and flows into the motor cavity through the cooling hole 902 on the motor pump housing to cool the motor assembly. That is, as the motor pump rotates, the cooling flow will intermittently shoot into the motor cavity as the high-pressure slipper passes through the cooling hole on the swash plate. When the slipper 4 passes through the cooling hole 201 on the swash plate 1, the low-pressure chamber 11 oil in the plunger 5 and the cylinder block 3 is lower than the pressure in the motor cavity. At this time, the oil flows into the slipper 4 and the plunger 5 through the cooling hole 901 of the motor pump housing, the cooling hole 103 of the swash plate seat, the cooling groove 101 and the cooling hole 201 on the swash plate in sequence. That is, as the motor pump rotates, the cooling flow will intermittently flow out of the motor cavity as the low-pressure slipper passes through the cooling hole on the swash plate. The above cooling flow direction constitutes a circulating cooling channel. When the slipper does not pass through the swash plate, the circulating cooling channel is not opened. At this time, the cooling flow flows into or into the motor cavity through the annular gap 903 between the motor pump shaft 10 and the motor pump housing, thus avoiding the phenomena of pressure buildup and cavitation that may occur when only one side of the slipper passes through the cooling hole. (Although it is possible to arrange the cooling holes at positions corresponding to the positions of the slippers to ensure that there are always slippers on both sides passing through the cooling holes at the same time to avoid cavitation or pressure buildup, this method is not necessary). Through the above embodiments, it can be found that for a self-cooling integrated wet motor pump proposed by the present invention, its cooling flow is driven by the high-pressure chamber and the low-pressure chamber of the piston pump and the pressure difference to circulate. When the output torque of the motor pump is large, the heat generation of the motor assembly is more serious. At this time, the pressure difference of the piston pump is also larger, and the cooling flow is more, which can better dissipate the heat of the motor assembly. When the output torque of the motor is small, the heat generation of the motor is also small. At this time, the pressure difference of the piston pump decreases, and the cooling flow decreases, thereby reducing the internal leakage of the motor pump. It can be seen that this motor pump has the ability to adaptively adjust the cooling flow.

[0027] The content not described in detail in this specification belongs to the prior art well-known to those skilled in the art. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes falling within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A self-cooling integrated wet motor pump, characterized in that: It includes a plunger pump assembly, a motor assembly and a motor pump housing; there are cooling holes on the swash plate assembly of the plunger assembly and the motor pump housing, and the cooling holes are located on the movement trajectory of the sliding shoe. When the plunger assembly of the pump rotates, the high-pressure plunger cavity injects the internal high-pressure oil into the motor assembly through the cooling hole, and sucks the oil back through the low-pressure plunger cavity, and cools the motor assembly through the oil suction and discharge process. Since the flow rate of the cooling medium depends on the pressure in the plunger, when the motor pump is heavily loaded, the pressure in the plunger is high and the cooling flow rate is large, forming an adaptive cooling structure that changes with the load.

2. The self-cooling integrated wet motor pump according to claim 1, characterized in that: The motor assembly and the plunger pump assembly share a motor pump housing and a motor pump shaft; the motor pump housing and the motor pump shaft divide the inside of the motor pump into a motor chamber and a plunger pump chamber; the plunger pump is composed of a swash plate seat, a swash plate, a cylinder body, a low-pressure sliding shoe, a low-pressure plunger, a distributor plate, a high-pressure sliding shoe, and a high-pressure plunger; The swash plate is provided with two pairs of cooling holes, namely, an oil discharge cooling hole and an oil suction cooling hole, and the swash plate is also provided with a pin groove; The swash plate seat is provided with two cooling channels and a pin hole. The swash plate is matched with the swash plate seat by a pin. The cooling channel is composed of an elliptical arc-shaped cooling groove and a cooling hole. The first cooling groove of the swash plate seat and the first cooling hole of the swash plate seat constitute a cooling channel. The second cooling groove of the swash plate seat and the second cooling hole of the swash plate seat constitute a second cooling channel. The first cooling hole on the swash plate corresponds to the first cooling groove on the swash plate seat, and the second cooling hole corresponds to the second cooling groove on the swash plate seat. When the high-pressure slipper passes through the second cooling hole on the swash plate, the oil in the high-pressure chamber of the high-pressure plunger and the cylinder body flows into the second cooling hole of the swash plate through the channel in the high-pressure plunger and the channel in the slipper in turn, and then flows into the motor pump housing through the second cooling groove and the second cooling hole on the swash plate seat, and flows into the motor cavity through the second cooling hole on the motor pump housing to cool the motor assembly. That is, as the motor pump rotates, the cooling flow will intermittently inject into the motor cavity through the cooling hole on the swash plate along with the high-pressure slipper.

3. The self-cooling integrated wet motor pump according to claim 2, characterized in that: When the low-pressure slipper passes through the first cooling hole on the swash plate, the pressure of the low-pressure cavity oil in the low-pressure plunger and the cylinder body is lower than that in the motor cavity. At this time, the oil flows into the low-pressure slipper and the low-pressure plunger through the first cooling hole of the motor pump housing, the first cooling hole of the swash plate seat, the first cooling groove and the first cooling hole on the swash plate in sequence. That is, as the motor pump rotates, the cooling flow will intermittently flow out of the motor cavity along with the low-pressure slipper through the cooling hole on the swash plate; the above-mentioned cooling flow direction constitutes a circulating cooling channel.

4. The self-cooling integrated wet motor pump according to claim 3, characterized in that: When the low-pressure slipper does not pass through the swash plate, the circulating cooling channel is not opened. The cooling flow at this time flows into or into the motor cavity through the annular gap between the motor pump shaft and the motor pump housing, thereby avoiding the pressure buildup and air suction that may be caused when only one side of the slipper flows through the cooling hole.

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