An electric vacuum pump with air cooling

Abstract

The present invention relates to an electric vacuum pump with air cooling, which is used for vacuuming automobile brake systems. The vacuum pump includes a pump core assembly and a motor assembly. The pump core assembly is arranged on the motor assembly. The pump core assembly includes a pump chamber. The pump chamber includes a pump chamber lower cover, a pump chamber upper cover, a stator, a rotor and a plurality of blades. The stator, rotor and a plurality of blades are arranged between the pump chamber lower cover and the pump chamber upper cover. The blades are inserted into the rotor so as to be able to move in and out. The rotor is arranged in the inner cavity of the stator to divide the inner cavity of the stator into a first working cavity, a second working cavity and an air-cooling cavity. The plurality of blades and the side walls of the stator are fitted in the first working cavity, the second working cavity and the air-cooling cavity to form a plurality of compartments. The product structure of the present application is simple. The cold air swirls in the pump core and then is discharged out of the pump, taking away the heat. The heat dissipation efficiency is greatly improved, and the vacuum pump is always in a relatively low temperature state.

Description

Technical Field

[0001] The present invention relates to an automobile brake booster device, in particular to an automobile electric vacuum pump with an air cooling function. Background Art

[0002] At the current stage of socio-economic development, people are becoming increasingly aware of environmental protection and demanding a low-carbon economy and lifestyle. Meanwhile, oil prices are rising, prompting an urgent search for new technologies in the automotive industry to replace traditional ones. Against this backdrop, fuel cell vehicles (FCVs) or electric vehicles modified from existing internal combustion engine vehicles have been vigorously developed to address the energy crisis and environmental pollution. Most FCVs utilize a vacuum-assisted servo braking system, combining both human and power. The vacuum source for the brake system vacuum booster in traditional ICE vehicles comes from the engine intake manifold or a mechanical vacuum pump. For pure EVs or FCVs modified from traditional models, the brake system lacks a vacuum power source due to the lack of an engine, resulting in the loss of the vacuum boost function. The braking force generated solely by human power is insufficient to meet the needs of driving. Consequently, with the rapid advancement of vehicle driving methods, more and more vehicles are relying on external vacuum sources to provide the boost vacuum during braking. Consequently, the use of electric vacuum pumps for vehicles is becoming increasingly widespread.

[0003] Prior art rotary vane automotive vacuum pumps, such as that disclosed in Patent No. 201611149458.9, suffer from the following issues: During operation, high-speed friction occurs between the rotor (consisting of rotor and vanes) and the stator in the pump core. This causes a significant temperature rise after a period of operation. With little gas flow within the pump core, the heat generated by this intense friction can only be dissipated through radiation, which is inefficient. A significant amount of heat is then transferred through conduction to heat the entire vacuum pump, causing overall temperature rise and potentially burning out. Under normal circumstances, the vacuum pump operates intermittently: when a sensor detects insufficient vacuum in the brake booster, the vehicle control system activates the vacuum pump. When the vacuum reaches the set level, the control system shuts down the vacuum pump, repeating the cycle. This keeps the temperature rise in the pump core due to friction low and prevents damage to the vacuum pump. However, under certain abnormal circumstances, such as a control system malfunction, causing the vacuum pump to continue operating, the temperature rise in the pump core can be very high. This heat is then transferred to the motor, causing burns in motor components and ultimately damaging the entire vacuum pump. This is one of the main failure modes of this type of electric vacuum pump.

[0004] In summary, there is still room for improvement in the existing electric vacuum pumps. Summary of the Invention

[0005] In view of the above-mentioned defects, the purpose of the present invention is to provide an electric vacuum pump for automobiles with a simple structure and an air cooling function to solve the existing technical problems.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] An electric vacuum pump with air cooling is used for vacuuming an automobile brake system. The vacuum pump includes a pump core assembly and a motor assembly. The pump core assembly is arranged on the motor assembly. The pump core assembly includes a pump chamber. The pump chamber includes a pump chamber lower cover, a pump chamber upper cover, a stator, a rotor and a plurality of blades. The stator, rotor and a plurality of blades are arranged between the pump chamber lower cover and the pump chamber upper cover. The blades are inserted into the rotor in an accessible manner. The rotor is arranged in the inner cavity of the stator to divide the inner cavity of the stator into a first working cavity, a second working cavity and an air-cooling cavity. The plurality of blades and the side walls of the stator are fitted into the first working cavity, the second working cavity and the air-cooling cavity to form a plurality of compartments.

[0008] According to the air-cooled electric vacuum pump described in a preferred embodiment of the present invention, the pump core assembly also includes an end cover, the inner cavity of the end cover includes an air inlet cavity and an air cavity, the air inlet cavity is connected to the braking system through an air inlet, and the air cavity is connected to the atmosphere through an atmospheric pipe.

[0009] According to the electric vacuum pump with air cooling described in a preferred embodiment of the present invention, the pump core assembly also includes a filter silencer, and the filter silencer is connected to the inlet end of the atmospheric pipe.

[0010] According to the air-cooled electric vacuum pump described in the preferred embodiment of the present invention, the pump core assembly also includes a sealing ring, a silencer and an outer cover, the outer cover is arranged on the end cover to form an accommodating space, and the pump chamber is arranged in the accommodating space; the sealing ring is arranged between the outer cover and the end cover to prevent air leakage; the silencer is arranged in the accommodating space, one end of the silencer is connected to the pump chamber upper cover, and the other end of the silencer is connected to the inner wall of the outer cover with a ventilation hole.

[0011] According to the air-cooled electric vacuum pump described in a preferred embodiment of the present invention, the motor assembly includes a motor output shaft and a drive block, the motor output shaft passes through the center hole of the lower cover of the pump chamber, and one end of the motor output shaft is inserted into the center hole of the rotor; the motor output shaft is fixedly connected to the rotor through the drive block, and the rotor drives the motor output shaft.

[0012] The design idea of ​​the present application is: to design a new structure of a pump core combination of an electric vacuum pump, the pump chamber of the pump core combination adopts a three-chamber structure, two of which (working chambers) are connected to the brake booster and are used to pump air so that the inner cavity of the brake booster reaches and maintains the required vacuum requirement; the other cavity (air-cooling chamber) is connected to the atmosphere, and when working, the cold air outside the vacuum pump is drawn into the pump chamber and then pumped out. The cold air flows in a zigzag manner inside and outside the cavity of the pump chamber and then discharges the vacuum pump, taking away heat, thereby achieving the effect of controlling the temperature rise of the vacuum pump; such a design can effectively control the temperature rise of the vacuum pump, thereby protecting the vacuum pump motor and the entire vacuum pump so that it will not burn due to high temperature.

[0013] Due to the adoption of the above technical features, the present invention has the following advantages and positive effects compared with the prior art:

[0014] First, the product structure of this application is simple. Cold air swirls inside the pump core assembly and then is discharged outside the pump, taking away heat. The heat dissipation efficiency is greatly improved, and the vacuum pump is always kept at a low temperature.

[0015] Second, the present application installs a filter silencer at the cold air inlet of the pump core assembly to prevent dust in the air from entering the pump chamber and damaging the pump chamber components;

[0016] Third, the filter silencer of the present application reduces noise and provides a more comfortable driving environment.

[0017] Of course, any specific embodiment of the present invention does not necessarily have all of the above technical effects at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the vacuum pump for this application;

[0019] Figure 2 This is a schematic diagram of the appearance of the vacuum pump of this application from another angle;

[0020] Figure 3 This is a schematic cross-sectional view of the pump core assembly of this application;

[0021] Figure 4 This is a schematic diagram of the connection between the stator, rotor and blades of this application;

[0022] Figure 5 This is a schematic cross-sectional view of the end cover of this application. DETAILED DESCRIPTION

[0023] Several preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the present invention is not limited to these embodiments. The present invention encompasses any alternatives, modifications, equivalent methods, and solutions that are not inconsistent with the spirit and scope of the present invention. To provide a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, but those skilled in the art will be able to fully understand the present invention without these detailed descriptions. Furthermore, to avoid unnecessary confusion regarding the essence of the present invention, well-known methods, processes, procedures, components, and the like are not described in detail.

[0024] Please refer to Figure 1 and Figure 2 , Schematic diagram of the appearance of the vacuum pump of the present application, an electric vacuum pump with air cooling of the present application is used for vacuuming the automobile brake system. In the embodiment of the present application, the air in the brake booster cavity is pumped out to form a vacuum. The vacuum pump includes a pump core assembly 100 and a motor assembly 200. The pump core assembly 100 is arranged on the motor assembly 200. In the embodiment of the present application, the pump core assembly 100 is locked to the motor assembly 200 with a screw. When the vacuum pump is working, the brake booster cavity is evacuated to a set vacuum degree; wherein, the pump core assembly 100 includes a pump chamber, please refer to Figure 3 This is a schematic cross-sectional view of the pump core assembly of this application. In the figure, the pump chamber includes a pump chamber lower cover 7, a pump chamber upper cover 10, a stator 8, a rotor 9 and a plurality of blades 11. The stator 8, the rotor 9 and the plurality of blades 11 are arranged between the pump chamber lower cover 7 and the pump chamber upper cover 10. Please also refer to Figure 3 、 Figure 4 and Figure 5 The pump chamber lower cover 7, the stator 8 and the pump chamber upper cover 10 are locked together with screws, and the screws continue to move downward into the threaded holes of the end covers. Therefore, the assembled pump chamber lower cover 7, the stator 8 and the pump chamber upper cover 10 will not rotate.

[0025] Figure 4 In the embodiment, the blades 11 are inserted into the rotor 9 so as to be removable, specifically, they are inserted into the grooves provided on the rotor 9; the rotor 9 is arranged in the inner cavity of the stator 8, as shown in FIG. Figure 4 As shown, the inner cavity of the stator 8 is divided into three cavities: a first working cavity 81, a second working cavity 82 and an air-cooling cavity 83. The plurality of blades 11 and the side walls of the stator 8 are attached to the first working cavity 81, the second working cavity 82 and the air-cooling cavity 83 to form a plurality of compartments. Specifically, when the vacuum pump is working, the rotor 9 and the blades 11 in the pump chamber rotate at a high speed. Due to the action of centrifugal force, the blades 11 are attached to the side walls of the stator 8, forming a plurality of compartments with several other parts of the pump chamber. The volume of each compartment cyclically changes from large to small, continuously pumping out the air in the brake booster cavity to form a vacuum.

[0026] like Figure 4 As shown, the rotor 9 is a perfect circle, and the inner cavity of the stator 8 is formed by three lines tangent to the rotor 9 combined with three arcs. The space between these three arcs and the outer edge of the rotor 9 is the first working cavity 81, the second working cavity 82 and the air-cooling cavity 83. When the blade 11 enters the first working cavity 81, the second working cavity 82 and the air-cooling cavity 83, it will extend out of the groove of the rotor 9 and fit into the side wall of the stator 8 due to the action of centrifugal force. When it encounters a place where the lines are tangent, it will sink into the groove of the rotor 9.

[0027] Please refer to Figure 5 The cross-sectional schematic diagram of the end cover of the present application shows that the pump core assembly 100 also includes an end cover 2, the inner cavity of the end cover 2 includes an air inlet cavity 21 and an air cavity 22, the air inlet cavity 21 and the air cavity 22 are not connected to each other, the air inlet cavity 21 is connected to the braking system, such as the inner cavity of the brake booster, through the air inlet port 23, and the air cavity 22 is connected to the atmosphere through the atmospheric pipe 24; in view of the design that the inner cavity of the stator 8 is three-cavity, the end cover 2 of the pump core assembly 100 is designed accordingly: the integral air inlet cavity of the prior art is separated to form two cavities that are not connected to each other: the air inlet cavity 21 and the air cavity 22, the two ends of the air inlet cavity 21 are respectively connected to the inner cavity of the brake booster and the working cavity of the pump chamber, please also refer to Figure 3 and Figure 4 The air intake chamber 21 is connected to the pump chamber working chamber by, in the embodiment of the present application, an air intake hole 71 is provided on the pump chamber lower cover 7 before the vanes 11 are inserted into the grooves of the rotor 9 in the first and second working chambers 81 and 82, respectively. Furthermore, both ends of the air chamber 22 are connected to the air outside the vacuum pump and the pump chamber air-cooling chamber 83, respectively. The air chamber 22 and the air-cooling chamber 83 are connected by, in the embodiment of the present application, an air intake hole 71 is provided on the pump chamber lower cover 7 before the vanes 11 are inserted into the grooves of the rotor 9 in the air-cooling chamber 83. In this way, the two air flows do not intersect before entering the pump chamber, thereby preventing the normal operation of the vacuum pump from being affected.

[0028] like Figure 5 As shown, the pump core assembly 100 also includes a filter-silencer 12, which is connected to the inlet end of the atmospheric pipe 24. The air outside the vacuum pump can be regarded as cold air at room temperature. During operation, the pump chamber draws cold air from the outside of the vacuum pump into the pump core assembly and then pumps it out. The cold air flows in a zigzag manner inside and outside the cavity of the pump chamber and then is discharged from the vacuum pump, taking away heat, thereby achieving the effect of controlling the temperature rise of the vacuum pump. The filter-silencer 12 is installed at the cold air inlet of the pump core assembly to prevent dust in the air from entering the pump chamber and damaging the pump chamber components, while reducing noise.

[0029] Figure 3 In the embodiment, the pump core assembly further includes a sealing ring 4, a silencer ring 5 and an outer cover 6, the outer cover 6 is arranged on the end cover 2 to form an accommodating space, and the pump chamber is arranged in the accommodating space; the sealing ring 4 is arranged between the outer cover 6 and the end cover 2 to prevent air leakage; the silencer ring 5 is arranged in the accommodating space, one end of the silencer ring 5 is connected to the pump chamber upper cover 10, and the other end of the silencer ring 5 is connected to the inner wall of the outer cover 6 with a ventilation hole 61. After assembly, a silencer space is formed between the silencer ring 5, the inner wall of the outer cover 6 and the pump chamber upper cover 10. In the embodiment of the present application, the inner wall of the outer cover 6 includes an annular ring body, the silencer ring 5 is sleeved and connected to the annular ring body, the ventilation hole 61 is a through hole opened on the annular ring body, and the ventilation hole 61 connects the silencer space with the outer cover space. Figure 3 The arrows in the figure indicate the flow direction of the gas. Driven by the blades 11, the gas entering the pump chamber enters the silencer space through the exhaust hole 101 provided on the pump chamber upper cover 10, and then flows from the ventilation holes 61 to the outer cover space and is discharged through the exhaust port 25 of the end cover 2. The silencer ring 5 mainly covers the space from the exhaust hole 101 of the pump chamber upper cover 10 to the ventilation holes 61, thereby reducing the gas noise discharged from the pump chamber in the vacuum pump.

[0030] In driving the rotor 9 and blades 11, Figure 3 The motor combination 200 includes a motor shaft 1 and a drive block 3 to provide power for the rotation of the rotor 9 and the blades 11. The motor shaft 1 passes through the center hole of the pump chamber lower cover 7, and one end of the motor shaft 1 is inserted into the center hole of the rotor 9; the motor shaft 1 is fixedly connected to the rotor 9 through the drive block 3, and the rotor 9 drives the motor shaft 1 in conjunction with the motor shaft 1.

[0031] The process of vacuum pump airflow in this application is:

[0032] 1. The air in the brake booster cavity enters the air inlet cavity 21 of the end cover 2 from the air inlet 23 of the end cover 2, and the cold air enters the air cavity 22 of the end cover 2 from the atmospheric duct 24 of the end cover 2;

[0033] 2. The airflow enters the compartment of the pump chamber from the air cavity of the end cover 2 through the air inlet hole 71 of the pump chamber lower cover 7;

[0034] 3. The air flow is squeezed through the pump chamber compartment and discharged from the exhaust through-hole 101 of the pump chamber upper cover 10, and enters the silencing space composed of the muffler 5 and the outer cover 6. The silencing space is provided with a ventilation hole 61 which is connected to the outer cover space;

[0035] 4. The airflow enters the outer cover space through the ventilation holes 61, flows around the outer wall of the pump chamber and is discharged from the exhaust port 25 of the end cover 2.

[0036] To sum up, the electric vacuum pump for automobiles with air cooling function of the present application has a pump chamber of the pump core assembly that pumps the air in the inner cavity of the brake booster and the cold air outside the vacuum pump into the pump core assembly at the same time, and the air is discharged from the exhaust port 25 of the end cover 2 of the pump core assembly after a zigzag flow, which can not only realize the function of the vacuum pump, but also effectively control the temperature rise of the entire vacuum pump body.

[0037] After testing, the vacuum pump of this application has achieved the performance of both meeting the function and controlling the temperature rise of the vacuum pump body, and the noise has not increased. The following table is the test data:

[0038]

[0039] As shown in the table above, the vacuum pump of this application adds a cavity as an air-cooling cavity, which is used to draw cold air from outside the pump into the cavity when the vacuum pump is operating. The cold air swirls within the pump core assembly and is then discharged outside the pump, removing the heat generated by friction during operation. This greatly improves heat dissipation efficiency and maintains the vacuum pump at a consistently low temperature. While having this advantage, this application also possesses the following basic performance:

[0040] 1. The vacuum pump of the present application still has two working chambers, and its working performance is the same as that of the vacuum pump in the prior art. For example, the maximum vacuum degree and the pumping rate are completely consistent after actual measurement;

[0041] 2. The vacuum pump of the present application is equipped with a filter silencer at the cold air inlet, and its noise level fully meets the industry standards or the noise requirements of various automobile manufacturers for this type of vacuum pump.

[0042] It should be noted that in the description of the embodiments of the present application, the terms "front, rear", "left, right", "up, down", etc. indicating directions or positional relationships are all based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present application. The terms "install", "connect", and "connected" should be understood in a broad sense. For example, they can be fixedly connected, detachably connected, or integrally connected; they can be directly connected, or indirectly connected through an intermediate medium, or they can be internal connections between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] In summary, due to the adoption of the above technical features, the present invention has the following advantages and positive effects compared with the prior art:

[0044] First, the product structure of this application is simple. Cold air swirls inside the pump core assembly and then is discharged outside the pump, taking away heat. The heat dissipation efficiency is greatly improved, and the vacuum pump is always kept at a low temperature.

[0045] Second, the present application installs a filter silencer at the cold air inlet of the pump core assembly to prevent dust in the air from entering the pump chamber and damaging the pump chamber components;

[0046] Third, the filter silencer of the present application reduces noise and provides a more comfortable driving environment.

[0047] The preferred embodiments of the invention are only used to help illustrate the invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made based on the contents of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the invention, so that those skilled in the art can make good use of the invention. The present invention is only limited by the claims and their full scope and equivalents. The above disclosure is only the preferred embodiment of the present invention, but it is not intended to limit itself. Any equivalent changes and modifications made by any person skilled in the art without violating the spirit and connotation of the invention should fall within the scope of protection of the present invention.

Claims

1. An electric vacuum pump with air cooling, used for vacuuming an automobile brake system, the vacuum pump comprising a pump core assembly and a motor assembly, the pump core assembly being arranged on the motor assembly, characterized in that: The pump core assembly includes a pump chamber, the pump chamber includes a pump chamber lower cover, a pump chamber upper cover, a stator, a rotor and a plurality of blades, the stator, rotor and a plurality of blades are arranged between the pump chamber lower cover and the pump chamber upper cover, and an air intake hole is provided on the pump chamber lower cover; the blades are inserted into the grooves on the rotor so as to be able to enter and exit; the rotor is arranged in the inner cavity of the stator to divide the inner cavity of the stator into a first working cavity, a second working cavity and an air cooling cavity, and a plurality of the blades and the side walls of the stator are fitted into the first working cavity, the second working cavity and the air cooling cavity to form a plurality of compartments; the rotor is a perfect circle, and the inner cavity of the stator is formed by three lines tangent to the rotor and three arcs, and the spaces between the three arcs and the outer edge of the rotor are respectively the first working cavity, the second working cavity and the air cooling cavity. cavity, when the blades enter the first working cavity, the second working cavity and the air-cooling cavity, they will extend out of the groove of the rotor and fit into the side wall of the stator due to the action of centrifugal force, and when they encounter a tangent line, they will sink into the groove of the rotor; the pump core assembly also includes an end cover, the inner cavity of the end cover includes an air intake cavity and an air cavity, the air intake cavity is connected to the braking system through the air inlet, and the air cavity is connected to the atmosphere through the atmospheric pipe; the air intake cavity and the air cavity are not connected to each other; in the first working cavity and the second working cavity, before the blades are immersed in the groove of the rotor, the air intake cavity and the pump chamber working cavity are connected, and in the air-cooling cavity, before the blades are immersed in the groove of the rotor, the air cavity and the air-cooling cavity are connected. The two air flows do not communicate with each other before entering the pump chamber, and will not affect the normal operation of the vacuum pump.

2. The electric vacuum pump with air cooling according to claim 1, characterized in that The pump core assembly further includes a filter silencer connected to the inlet end of the atmospheric pipe.

3. The electric vacuum pump with air cooling according to claim 2, characterized in that The pump core assembly also includes a sealing ring, a silencer and an outer cover. The outer cover is arranged on the end cover to form an accommodating space, and the pump chamber is arranged in the accommodating space; the sealing ring is arranged between the outer cover and the end cover to prevent air leakage; the silencer is arranged in the accommodating space, one end of the silencer is connected to the pump chamber upper cover, and the other end of the silencer is connected to the inner wall of the outer cover with a ventilation hole.

4. The electric vacuum pump with air cooling according to claim 3, characterized in that The motor assembly includes a motor output shaft and a drive block. The motor output shaft passes through the center hole of the pump chamber lower cover, and one end of the motor output shaft is inserted into the center hole of the rotor; the motor output shaft is fixedly connected to the rotor through the drive block, and the rotor drives the motor output shaft in conjunction.

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