KR102056897B1 - Electric Pump - Google Patents

Abstract

The present invention includes a motor unit including a housing, a rotating shaft inserted into the housing, a rotor core disposed on an outer circumferential surface of the rotating shaft, and a stator core accommodating the rotor core; And a pump unit including an inner rotor and an outer rotor coupled to one end of the rotation shaft, wherein one side of the housing is provided with an insertion groove in which the pump unit is accommodated, and the motor unit and the pump in the housing. The electric pump in which the part is accommodated is disclosed.

Description

Electric Pump

The present invention relates to an electric pump.

In general, an electric oil pump (EOP) is a device for supplying oil to maintain a constant pressure therein for a smooth shifting function of an automobile transmission. In particular, in the case of HEV vehicles, there is a problem in that the engine is stopped when the vehicle is stopped, so that a constant pressure cannot be maintained on the transmission. To compensate for this, the pump serves to maintain oil pressure when the engine is stopped.

However, the conventional electric oil pump manufactures the pump, the motor, and the inverter separately and fastens the pump and the motor with bolts, and the inverter is manufactured by connecting with a separate cable. Therefore, existing products have pumps, motors, and inverters manufactured and assembled by individual companies, and thus have unnecessary structures in terms of performance, efficiency, and cost.

In particular, as each component is assembled separately, it is unnecessarily large in size, which is vulnerable to vibration, and because it is detachable, noise defects increase, and an additional structure (eg, bush) is required in terms of assembly to secure reliability. There is.

The present invention provides an electric pump that can eliminate the structure in consideration of unnecessary assembly by increasing the assembly reliability by making the pump and the motor integrally.

Electric pump according to one aspect of the invention, the housing; A motor unit including a stator disposed in the housing, a rotor, and a rotation shaft coupled to the rotor; A pump unit including an inner rotor and an outer rotor coupled to the rotating shaft; A first bearing supporting rotation of the rotation shaft; And a sealing member disposed between the motor part and the first bearing, wherein the housing has a first insertion groove in which the pump part is accommodated, and a second insertion groove in which the motor part is received, on the other side thereof. The housing is disposed between the first insertion groove and the second insertion groove, and includes a through hole through which the rotating shaft penetrates, and the through hole comprises a first hole of a first diameter and a second diameter of a second hole. And a third hole having a second hole and a third diameter, wherein the second hole connects the first hole and the third hole, the second diameter is smaller than the first diameter and larger than the third diameter, The sealing member is disposed in the first hole, the first bearing is disposed in the second hole, and fluid is introduced at an interval disposed between the inner circumferential surface of the third hole and the rotation shaft.

In the electric pump according to an aspect of the present invention, a main channel through which a fluid is pumped is formed on a bottom surface of the insertion groove, and the main channel is connected to a fluid inlet port and a fluid outlet port formed outside the housing.

In the electric pump according to an aspect of the present invention, an inside of the housing is formed with a suction channel connecting the fluid inlet and the main channel, and a discharge channel connecting the fluid outlet and the main channel.

In the electric pump according to an aspect of the present invention, a through hole in which the rotating shaft is inserted is formed in the center of the bottom surface of the insertion groove, and a bearing for rotatably supporting the rotating shaft is disposed on the inner wall of the through hole.

In the electric pump according to an aspect of the present invention, a gap is formed between the through hole and the rotating shaft to allow fluid to flow into the bearing.

In the electric pump according to an aspect of the present invention, a sealing member may be disposed between the bearing and the motor unit to block the inflow of fluid.

In the electric pump according to an aspect of the present invention, a first cover coupled to one side of the housing to seal the pump unit and a second cover coupled to the other side of the housing to seal the motor unit.

In the electric pump according to an aspect of the present invention, a sensing unit is disposed at the other end of the rotating shaft, and the sensing unit is sealed in the housing by the second cover.

In the electric pump according to an aspect of the present invention, it is formed integrally with the second cover and includes a drive unit for rotating the motor unit.

In the electric pump according to an aspect of the present invention, the circuit board of the driving unit is directly connected to the terminal of the motor unit.

According to the present invention, it is possible to reduce the volume by about 20 to 25% compared to the conventional combination of the motor and the pump, and it is possible to implement the in-buffer integrated pump even in the existing volume by mounting the inverter in the reserved extra space.

In addition, the mold of the pump and the mold of the motor are not manufactured separately, so that only one mold of the integrated housing is manufactured, thereby reducing the cost.

In addition, an alignment point is not required for alignment of the concentricity between the pump and the motor, and thus, manufacturing is simple and the process is simple.

In addition, since it is manufactured integrally, there is no need for a sealing structure for preventing leakage between the motor and the pump.

In addition, by designing the length of the rotating shaft short, unnecessary torque loss (Torque Loss) is prevented.

In addition, the integral body makes it easy to secure a pump-like oil channel (channel).

In addition, the center of gravity between the transmission coupling portion and the electric pump is closer to the vibration and to implement low noise.

In addition, it is easy to assemble the product with an integrated structure, and can prevent driving failure or noise failure due to alignment misalignment.

1 is a perspective view of an electric pump according to an embodiment of the present invention,
2 is an exploded perspective view of an electric pump according to an embodiment of the present invention;
3 is a view showing the flow of the fluid according to an embodiment of the present invention,
4 is a cross-sectional view of an electric pump according to an embodiment of the present invention,
5 is a view for explaining the position of the bearing and the sealing member according to an embodiment of the present invention,
FIG. 6 is an enlarged view of portion A of FIG. 4.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated and described in the drawings. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be referred to as the first component, and similarly, the first component may also be referred to as the second component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is said to be "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that another component may be present in the middle. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present disclosure does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings, and the same or corresponding components will be given the same reference numerals regardless of the reference numerals, and redundant description thereof will be omitted.

1 is a perspective view of an electric pump according to an embodiment of the present invention, Figure 2 is an exploded perspective view of the electric pump according to an embodiment of the present invention.

1 and 2, the electric pump according to an embodiment of the present invention is disposed on the housing 100, the rotary shaft 410 inserted into the housing 100, and the outer peripheral surface of the rotary shaft 410 A motor unit 400 including a rotor 420, and a stator 430 in which the rotor 420 is accommodated, an inner rotor 310 coupled to one end of the rotation shaft 410, and an outer rotor 320. It includes a pump unit 300 including.

The housing 100 is a cylindrical member, and an insertion groove 110 is formed at one side thereof to accommodate the pump 300. The depth of the insertion groove 110 may be manufactured to be the same as the thickness of the pump unit 300, but is not necessarily limited thereto and may be manufactured so that only a predetermined portion of the pump unit 300 is inserted. One side of the housing 100 is inserted into the pump unit 300 is coupled to the first cover 210 is sealed.

The mounting part 160 is formed in the housing 100. In the present invention exemplifies a structure in which the fluid inlet 120 and the fluid outlet 130 are formed in the mounting unit 160, but the positions of the inlet and outlet are not necessarily limited thereto. In addition, the shape and position of the mounting unit 160 may be variously modified according to the selection.

The pump unit 300 includes an inner rotor 310 coupled to one end of the rotation shaft 410 and an outer rotor 320 in which the inner rotor 310 is accommodated. N lobes are formed on the outer surface of the inner rotor 310, and N + 1 lobes are formed on the outer rotor 320 to rotate at a rotation ratio of (N + 1) / N.

The pump unit 300 has a certain eccentric structure when the inner rotor 310 rotates under rotational force from the rotation shaft 410. The eccentricity allows fluid fuel between the inner rotor 310 and the outer rotor 320. A volume that can be transported occurs.

That is, the portion of which the volume is increased during the rotational movement of the rotor sucks the surrounding fluid by the pressure drop, and the portion of which the volume is reduced discharges the fluid by the increase of the pressure. This pump structure can be applied to all the known structure bar further description will be omitted.

The motor unit 400 is inserted into the other side of the housing 100. The motor unit 400 may include any known configuration including a rotating shaft 410, a rotor 420 disposed on an outer circumferential surface of the rotating shaft 410, and a stator 430 in which the rotor 420 is accommodated. In detail, the motor unit 400 may be a brush motor or a brushless motor.

The bearing 500 is disposed between the pump unit 300 and the motor unit 400 to rotatably support the rotating shaft 410, and the sealing member 600 has a fluid circulated in the pump unit 300 by the motor unit ( 400) to block the inflow to the side.

The second cover 220 is coupled to the other side of the housing 100 to seal the motor unit 400, and various electronic / electric devices such as a motor driving unit may be inserted as necessary.

In the electric pump according to the exemplary embodiment of the present invention, since the motor unit 400 and the pump unit 300 are integrally accommodated in one housing 100, the structure for assembling the motor and the pump is eliminated. It is improved, and the overall size is smaller, which makes it possible to manufacture a compact motor.

The electric pump according to an embodiment of the present invention may operate as an oil pump, but may be suitably modified and used as a structure for pumping various fluids, such as a water pump, as necessary.

3 is a view showing the flow of the fluid according to an embodiment of the present invention.

Referring to FIG. 3, one side of the housing 100 is formed with an insertion groove 110 into which the pump unit 300 is inserted, and the insertion groove 110 is rotated at the bottom surface 113 of the pump unit 300. The main channel 111 in which the fluid is pumped by the pressure difference is formed.

The main channel 111 may be formed as a groove formed along the circumference of the bottom surface 113. In addition, a through hole 114 through which a rotating shaft is inserted is formed at the center of the bottom surface 113. Therefore, the rotating shaft is coupled to the inner rotor through the through hole 114, thereby transmitting the rotational force to the pump portion.

In more detail, the main channel 111 may include a first main channel 111a connected to an end of the suction channel 121 and a second main channel 111b connected to an end of the discharge channel 131.

Therefore, the fluid sucked through the fluid inlet 120 by the pump is introduced into the first main channel 111a through the suction channel 121, discharged to the second main channel 111b, and then discharge channel 131. ) May be discharged to the fluid outlet 130.

In the present invention, the first main channel 111a and the second main channel 111b have been described as an example, but the structure of the channel may be variously modified according to the selection of the transmission coupling position. In addition, the inlet channel 121 and the outlet channel 131 can also be changed in various structures to design the channel in the shortest distance.

Figure 4 is a cross-sectional view of the electric pump according to an embodiment of the present invention, 5 is a view for explaining the position of the bearing and the sealing member according to an embodiment of the present invention, Figure 6 is an enlarged view of a portion A of FIG. to be,

Referring to FIG. 4, a first bearing 500 rotatably supporting one side of the rotation shaft 410 is disposed on an inner wall of the through hole 114 into which the rotation shaft 410 is inserted. In addition, the second bearing 510 is disposed on the other side of the rotating shaft.

According to this structure, since the first bearing 500 is disposed near the end of the rotating shaft 410, the first bearing 500 can stably support the rotation of the rotating shaft 410, and the first bearing 500 can be used without using a separate bush. There is an advantage that can only stably support the axial load of the rotating shaft (410). In this case, the first bearing 500 may be designed to have a smaller diameter than the inner rotor 310 of the pump unit 300.

A sealing member 600 is disposed between the first bearing 500 and the motor unit 400 to block the inflow of the fluid. This sealing member 600 may be a known configuration such as an O-ring. An inner wall of the through hole 114 may have a space in which the first bearing 500 and the sealing member 600 may be installed.

According to the present invention, since the sealing member 600 is located between the bearing 500 and the motor unit 400, the inner diameter of the sealing member 600 is formed to be equal to or larger than the inner diameter of the bearing 500. It is advantageous to block the

Hereinafter, the reason why the first bearing 500 is disposed between the pump unit 300 and the sealing member 600 will be described. Referring to FIG. 5, when a load is applied to the pump unit 300, the sum of the loads applied between the first bearing 500 and the second bearing 510 satisfies Equation 1 below.

[Relationship 1]

Here, P _pump is a load applied to the pump unit 300, P _b1 is a load applied to the first bearing 500, and P _b2 is a load applied to the second bearing 510.

Further, the first bearing moment (M _b1) and the second bearing moment (M _b2) must have to satisfy the relational expression 2, and the moment of the first bearing (M _b1) and the moment of the second bearing (M _b2) of the Each may be represented by the following relational formula 3. Where L _b1 is the load distance of the first bearing, L _total is the total length.

[Relationship 2]

[Relationship 3]

Therefore, by substituting relation 3 in relation 1 and arranging terms, the following relation 4 can be derived.

[Relationship 4]

Referring to FIG. 5 and Equation 4, as the load distance L _b1 of the first bearing increases, the load P _{b1 applied} to the first bearing 500 increases. Therefore, it is preferable to reduce the load on the first bearing by reducing the load distance of the first bearing 500 to shorten the shaft system.

However, when the sealing member 600 is disposed between the pump unit 300 and the first bearing 500 as shown in FIG. 5, the pump unit 300 and the first bearing 500 are formed as much as the sealing member 600. Should be spaced apart. Therefore, the load of the first bearing 500 increases by the distance between the pump unit 300 and the first bearing 500, resulting in a decrease in the life of the pump.

That is, the first bearing 500 is disposed between the sealing member 600 and the pump portion 300, preferably close to the pump portion 300.

Referring to FIG. 6, the first bearing is disposed in the receiving groove 114a provided in the inner wall of the through hole, and a gap G is formed between the inner wall 114b of the through hole 114 and the rotation shaft 410.

Therefore, the fluid may flow into the first bearing 500 by the gap G to perform a lubrication function of the first bearing 500. A groove 311 is formed at the center of the contact surface of the inner rotor 310 so that the fluid can be easily inserted into the bearing. In addition, a slot may be further formed in the inner wall of the through hole 114b as necessary to increase the inflow of the fluid by widening the gap G.

The first bearing 500 may be selected from various products within a range in which no chemical reaction occurs with the dedicated grease. In addition, when the fluid is an automatic transmission fluid (ATF), the lubricant may sufficiently serve as a lubricant of the bearing.

However, the above configuration is not necessarily limited thereto, and various modifications are possible. For example, if it is necessary to block the fluid from flowing into the first bearing 500, a separate sealing member (not shown) may be installed in the gap G.

Referring back to FIG. 4, the sensing unit 700 is configured to monitor a rotational posture of the rotor 420, and all of the known sensing devices (resolvers, etc.) provided in the motor may be adopted. In addition, the sensing unit 700 may be sealed in the housing 100 by the second cover 220.

Therefore, according to the exemplary embodiment of the present invention, the pump unit 300, the motor unit 400, and the sensing unit 700 are all disposed inside the one housing 100, thereby allowing a compact structure.

According to the present invention, the driving unit 800 may be manufactured integrally with the second cover 220. Since the pump unit 300, the motor unit 400, and the sensing unit 700 are disposed in one housing 100, a space capable of integrating the driving unit 800 with the same standard as the existing electric motor is secured. can do.

In more detail, the driving unit 800 may be integrally coupled to the upper side of the second cover 220, but is not necessarily limited thereto and may be formed in the inner space of the second cover 220.

The driving unit 800 includes an inverter for rotating the motor 400 and an inverter driving unit, and the printed circuit board 801 embedded in the inverter and the u, v, w terminals 440 of the motor are directly connected to each other. The electrical reliability is improved and the structure is more compact than the structure using the cable. Specifically, the u, v, w terminals 440 of the printed circuit board 801 and the motor may be directly connected by soldering.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art various modifications and variations of the present invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

100: housing 110: insertion groove
111: main channel 210: first cover
300: pump unit 310: internal rotor
320: external rotor 400: motor portion
500: first bearing 600: sealing member
700: sensing unit 800: driving unit

Claims (10)

housing;
A motor unit including a stator disposed in the housing, a rotor, and a rotation shaft coupled to the rotor;
A pump unit including an inner rotor and an outer rotor coupled to the rotating shaft;
A first bearing disposed at one side of the motor unit to support rotation of the rotary shaft;
A second bearing disposed on the other side of the motor unit to support rotation of the rotary shaft; And
A sealing member disposed between the motor portion and the first bearing,
The housing has a first insertion groove for accommodating the pump portion disposed on one side thereof, and a second insertion groove for accommodating the motor portion disposed on the other side thereof.
The housing is disposed between the first insertion groove and the second insertion groove, and includes a through hole through which the rotating shaft passes,
The through hole includes a first hole having a first diameter, a second hole having a second diameter, and a third hole having a third diameter, wherein the second hole connects the first hole and the third hole,
The first hole is disposed between the pump part and the motor part, the third hole is disposed between the pump part and the first hole, and the second hole is between the first hole and the third hole. Deployed,
The second diameter is smaller than the first diameter and larger than the third diameter,
The sealing member is disposed in the first hole and the first bearing is disposed in the second hole,
An electric pump in which fluid flows in the space arranged between the inner peripheral surface of the said 3rd hole and the said rotating shaft.
The method of claim 1,
The main channel for pumping fluid is formed on the bottom surface of the first insertion groove, the main channel is connected to the fluid inlet and the fluid outlet formed in the housing.
The method of claim 2,
And an intake channel connecting the fluid inlet port and the main channel, and an outlet channel connecting the fluid outlet port and the main channel.
delete The method of claim 1,
The fluid introduced into the gap is introduced into the first bearing.
The method of claim 5,
The sealing member is an electric pump to block the fluid flowing into the motor unit.
The method of claim 1,
And a second cover coupled to one side of the housing to seal the pump unit, and a second cover coupled to the other side of the housing to seal the motor unit.
The method of claim 7, wherein
A sensing unit is disposed at the other end of the rotating shaft, and the sensing unit is sealed in the housing by the second cover.
The method of claim 7, wherein
And a driving part disposed in the second cover to rotate the motor part.
The method of claim 9,
Circuit board of the drive unit is an electric pump directly connected to the terminal of the motor unit.

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