JP2010265833A - Electric pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric pump capable of further surely reducing noise caused by the vibration of a motor, and suitable for a vacuum pump of, for example, an electric automobile. <P>SOLUTION: This electric pump includes: an installation stand 51 arranged between a pump 31 and a front end as the motor shaft 2 side of the motor 1 and supporting the pump 31 and the motor 1 while undergoing the penetration of a motor shaft 2 therethrough; a motor cover 8 for fixing the opening end side to the installation stand 51 in a bottomed cylindrical shape covering the motor 1; a first elastic member 21 while being compressed in the axial direction of the motor shaft 2 between a rear end of the motor 1 and a bottom 10 of the motor cover 8; and a second elastic member while being radially compressed with the motor shaft 2 as the substantial center. The motor 1 is energized to the installation stand 51 side in the axial direction of the motor shaft 2 by the first elastic member 21, and the motor 1 is radially energized to the motor shaft 2 side by the second elastic member. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electric pump in which a pump is connected to a motor shaft of an electric motor.

For example, when operating a brake booster similar to a gasoline engine vehicle in an electric vehicle, the electric vehicle does not generate negative pressure in the intake manifold as in a gasoline engine, so a separate vacuum pump is required (for example, , See Patent Document 1).
Such a vacuum pump is provided with a pump (for example, a vane type vacuum pump) connected to the motor shaft on the side where the motor shaft of the electric motor protrudes.

Moreover, although it is not a vacuum pump, the electric pump by which the pump was directly connected to the motor shaft of the electric motor and assembled was proposed (for example, refer patent document 2).
In the pump assembly of Patent Document 2, a pump assembly including a motor unit and a pump unit directly connected to the motor shaft of the motor unit is housed in one cylindrical case.

In the case, a cushion rubber formed in a dish shape so as to cover the pump side end portion is disposed between the pump side end outer surface and the case inner surface at the pump side end portion of the pump assembly.
Also, in the case, a cushion rubber formed in a dish shape so as to cover the motor part side end part is arranged between the motor part side end part outer surface and the case inner surface at the motor part side end part of the pump assembly. Has been. As a result, vibration and noise in the pump assembly are prevented.

Japanese Patent Laid-Open No. 10-329701 Japanese Utility Model Publication No. 63-21786

  By the way, in Patent Document 2, a pump assembly including a pump and a motor is supported by a case via a cushion rubber, and vibrations are prevented from being transmitted from the pump and the motor to the case. Although vibration and noise can be reduced, there is a limit to the absorption of vibration by the cushion rubber. Further, it is necessary to apply a rubber-like vibration absorbing member that absorbs vibration, and there are problems of deterioration and durability due to the use environment.

  The present invention has been made in view of the above circumstances, and has an object to provide an electric pump that includes a motor and a pump connected to a motor shaft, and can sufficiently suppress noise caused by vibration of the motor. To do. It is another object of the present invention to provide an electric pump having a highly durable mechanism for preventing noise caused by vibration.

The electric pump according to claim 1 is a pump;
A motor having a motor shaft coupled to the pump and driving the pump;
A support member that is disposed between the pump and a front end portion on the motor shaft side of the motor and supports the pump and the motor in a state where the motor shaft is penetrated;
A motor cover in which the open end side is fixed to the support member with a bottomed cylindrical shape covering the motor;
An elastic member in a compressed state is provided between the rear end of the motor and the bottom of the motor cover;
The elastic member biases and supports the motor to the support member.

  In the first aspect of the invention, the motor is supported in a cantilevered manner by a support member provided between the pump and the motor. At this time, the bottomed cylindrical motor fixed to the support member The motor is disposed in the cover, and an elastic member in a compressed state is disposed between the bottom of the motor cover and the rear end portion of the motor, so that the motor is moved toward the support member by the elastic member. It will be energized. At this time, the elastic member is assumed to be compressed in the axial direction of the motor.

  In this state, the elastic member urges the motor to the support member, and the reaction force generated in the elastic member acts in the direction toward the bottom of the motor cover. Further, depending on the compression state of the elastic member, the elastic member may be compressed in the radial direction of the motor, and the urging force from the elastic member is directed along the radial direction of the motor toward the axial direction of the motor. A biasing force acts. In this case, an urging force from the motor cover to the shaft center side of the motor acts by an elastic force of the elastic member, and a reaction force from the motor side toward the outer peripheral side acts.

By operating the motor in these states, when the motor vibrates due to rotation imbalance of the motor, transmission of pump vibration, etc., the biasing force and reaction force of the elastic member increase due to the vibration force of the motor. However, since the urging force and reaction force of the elastic member act on the support member that is the same member, the urging force and reaction force are canceled out, and the vibration can be attenuated, thereby reducing the noise due to the vibration of the motor. Can do.
In this case, the noise due to motor vibration can be more reliably reduced than when the motor is supported by the case with cushion rubber or the like, that is, when transmission of vibration between the motor and the case is cut off. You can plan. Further, since there is no need to use a vibration absorbing member that absorbs vibration, durability can be improved without being affected by the use environment.

The electric pump according to a second aspect is the invention according to the first aspect, wherein as the elastic member,
A first elastic member in a compressed state along the axial direction of the motor shaft is provided;
The motor is urged toward the support member along the axial direction of the motor shaft by the first elastic member.

  In the invention described in claim 2, since the first elastic member as the elastic member is compressed along the axial direction of the motor shaft, the elastic member is attached along the axial direction of the motor shaft as described above. The power and the reaction force accompanying it are in a state of acting. By arranging the elastic member in the axial direction, it is possible to suitably secure the installation area of the elastic member with respect to the motor and the motor cover, so that the biasing force generated by the elastic member and the reaction force can be reliably ensured by the support member. As a result, the force is canceled and the displacement of vibration is attenuated to prevent vibration and noise.

The electric pump according to a third aspect is the invention according to the first aspect or the second aspect, wherein as the elastic member,
A second elastic member in a compressed state is provided along a radial direction about the motor shaft;
The motor is biased along the radial direction by the second elastic member toward the motor shaft.

In the electric pump according to the third aspect, since the second elastic member as the elastic member is compressed along the radial direction about the motor shaft, as described above, An urging force or a reaction force is applied along the radial direction. When the motor vibrates in this state, the urging force and reaction force in the radial direction of the elastic member generated by the vibration force are canceled by the support member, and the vibration displacement is attenuated, thereby preventing vibration and noise.
In particular, the motor is in a cantilever state in which the front end side is supported by the support member, and the motor may vibrate so that the rear end side is displaced around the front end, but the rear end side of the motor is By being urged in the radial direction by the second elastic member, noise due to such vibration can be efficiently prevented. Moreover, it can arrange | position compactly compared with arrange | positioning an elastic member to an axial direction.

  According to the electric pump of the present invention, vibration and noise can be reduced more reliably. For example, when the electric pump is mounted on an electric vehicle, a quieter environment is provided to those who ride the electric vehicle. be able to. In addition, it is possible to reduce the structure for noise countermeasures in the motor cover, and it is possible to reduce the cost of the structure for noise countermeasures in the motor cover.

It is a side view which shows the electric pump of 1st Embodiment of this invention. It is sectional drawing which shows the said electric pump. It is a disassembled perspective view which shows the said electric pump. It is a perspective view which shows the 1st elastic member of the said electric pump. It is sectional drawing which shows the electric pump of 2nd Embodiment of this invention. It is a disassembled perspective view which shows the electric pump of 2nd Embodiment. It is a perspective view which shows the 2nd elastic member of the said electric pump.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described with reference to the accompanying drawings.
1 is a side view showing an electric pump according to a first embodiment of the present invention, FIG. 2 is a sectional view showing the electric pump, FIG. 3 is an exploded perspective view showing the electric pump, and FIG. 4 is a first view of the electric pump. It is a perspective view which shows this elastic member.

The electric pump of this example is, for example, a vacuum pump mounted on an electric vehicle, and is driven by a direct current of a battery mounted on the electric vehicle.
As shown in FIGS. 1 to 3, the electric pump includes a motor 1 and a pump 31, and a motor shaft 2 of the motor 1 is connected to a rotor 32 of the pump 31.
Further, the electric pump includes an attachment base (support member) 51 for fixing the electric pump at a predetermined position of the automobile.

The mounting base 51 includes a base 52 that is fixed to the automobile side, and a generally plate-like connection plate 53 that is erected (hangs down) on the base 52 and to which the motor 1 and the pump 31 are attached. The motor 1 is fixed to one side surface of the plate 53, and the pump 31 is fixed to the other side surface.
The motor 1 is a DC motor including a rotor and a stator (not shown) in a substantially cylindrical case 3, and a motor shaft 2 that rotates integrally with the rotor protrudes from the tip of the case 3.

The front end portion of the motor 1 from which the motor shaft 2 protrudes is provided with a protruding portion that protrudes at the center thereof. A mounting plate 4 having an engagement hole with which the protrusion is engaged is fixed to the tip of the motor 1 with screws 5.
The mounting plate 4 is fixed to one side surface of the connection plate 53 of the mounting base 51 with screws 6.

Further, a through hole through which the motor shaft 2 of the motor 1 passes is formed at the center of the connection plate 53, and the tip of the motor shaft 2 that passes through the connection plate 53 reaches the rotor 32 in the pump 31. ing.
The periphery of the central projecting portion of the motor 1 is connected to the connection plate 53 via the attachment plate 4 and is covered with the connection plate 53.

  Further, the outer peripheral surface and the rear end surface except for the front end surface of the motor 1 are covered with a bottomed cylindrical motor cover 8. The motor cover 8 is fixed to the connection plate 53 with screws 11 at one end of the opened motor cover 8 around the tip of the motor 1. The front end of the motor cover 8 has a flange shape, and the seal ring 12 is disposed between the connection plate 53 and the front end surface of the motor cover 8.

The motor cover 8 includes a substantially cylindrical tube portion 9 and a substantially disk-shaped bottom portion 10 that is attached to the rear end portion of the tube portion 9 and closes the opening of the rear end portion. The bottom portion 10 is fixed to the rear end portion of the cylindrical portion 9 with screws 13.
A seal ring 14 is disposed between the bottom portion 10 and the tube portion 9.
The motor 1 and the motor cover 8 are connected via the connection plate 53, but a gap is provided between the outer peripheral surface of the motor 1 and the inner peripheral surface of the cylinder portion 9 of the motor cover 8. ing. A space is also provided between the rear end surface of the motor 1 and the bottom 10 of the motor cover 8. Therefore, the motor 1 and the motor cover 8 are not in contact with each other.

A pump 31 is connected to the other side surface of the connection plate 53. The pump 31 includes a pump unit 33 in which a rotor 32 to which the motor shaft 2 is connected is disposed, and a pump cover 34 that covers the periphery of the pump unit 33.
The pump unit 33 includes, for example, a rotor 32 having vanes, and the case of the pump unit 33 includes a suction port and a discharge port.

The suction port is provided on the surface side connected to the connection plate 53 of the pump unit 33. The pump unit 33 is connected to the connection plate 53 by screws.
A concave portion communicating with the suction port of the pump unit is provided in the connection plate 53, and a suction path is connected to the concave portion. The suction path opens to the outer peripheral surface of the connection plate 53, and a suction pipe is connected to the suction path. 54 is connected.

The pump cover 34 covering the pump unit 33 is formed in a covered cylinder shape, and an open end (bottom) is connected to a portion on the other side of the connection plate 53 outside the pump unit 33 by screws 56. ing. A seal ring 55 is disposed between the pump cover 34 and the connection plate 53.
There is a space between the pump cover 34 and the pump unit 33, and the pump cover 34 and the pump unit 33 are connected via the connection plate 53, but the pump cover 34 and the pump unit 33 are not in direct contact with each other.

A cylindrical projection 7 is provided at the center of the rear end of the motor 1. The protrusion 7 and the motor shaft 2 are arranged coaxially.
Further, a cylindrical projecting portion 16 that projects toward the periphery of the projecting portion 7 is formed on the bottom portion 10 of the motor cover 8 at a portion facing the projecting portion 7.
The cylindrical projecting portion 16 is in a state of covering the outer peripheral surface of the projecting portion 7 on the rear end surface of the motor 1, and a state in which the tip is close to a portion around the projecting portion 7 on the rear end surface of the motor 1. It has become.

In addition, the outer peripheral surface of the protrusion 7 at the rear end of the motor 1 and the inner peripheral surface of the cylindrical protrusion 16 of the bottom 10 of the motor cover 8 are opposed to each other with a gap. Further, the protruding portion 7 of the motor 1 and the cylindrical protruding portion 16 of the bottom portion 10 are arranged on the same axis.
The cylindrical protruding portion 16 has a step 19 between the inner peripheral portion 17 and the outer peripheral portion 18 and protrudes long so that the inner peripheral portion 17 is close to the rear end surface of the motor 1 as described above. On the other hand, the outer peripheral portion 18 is in a lower state. That is, the amount of protrusion from the inner surface of the bottom portion 10 is larger in the inner peripheral portion 17 than in the outer peripheral portion 18, the inner peripheral portion 17 is close to the rear end surface of the motor 1, and the outer peripheral portion 18 is the rear end surface of the motor 1. It is in a state away from.

And between the front end surface of the outer peripheral part 18 and the rear-end surface of the motor 1, the 1st elastic member 21 as a leaf | plate spring of a substantially diaphragm shape (disc spring shape) is arrange | positioned.
As shown in FIG. 4, the first elastic member 21 has a substantially truncated cone shape and a cylindrical shape (dish shape, diaphragm shape), and an inner peripheral portion of the cylindrical protruding portion 16 at the center portion. A circular opening 22 into which 17 is inserted is formed.
In addition, the circumference of the circular opening 22 of the first elastic member 21 is a ring portion 23 composed of a short cylindrical portion and a portion extending in an annular shape from the tip end (bottom 10 side end) to the periphery. Is formed.

Around the ring portion 23, there is provided a leaf spring portion 24 that is inclined obliquely (in a truncated cone shape) from the inner surface side of the bottom portion 10 toward the rear end surface side of the motor 1 as it goes radially outward. It has been. The leaf spring portion 24 is provided with two first cutout portions 25 that extend from the outer peripheral edge of the leaf spring portion 24 to the outer peripheral edge of the ring portion 23 and have a wide width along the circumferential direction. ing.
By these two first cutout portions 25, the leaf spring portion 24 is divided into two. Further, in the center of each of the two portions of the leaf spring portion 24, a second notch portion 26 that is narrower and shallower than the notch portion 25 is provided.

The first elastic member 21 is in a state where the inner peripheral portion 17 of the cylindrical protrusion 16 of the bottom portion 10 of the motor cover 8 is inserted into the circular opening 22 inside the ring portion 23. The side surface on the tip side of the ring portion 23 is in contact with the end surface of the outer peripheral portion 18 of the cylindrical protrusion 16.
Further, the front end portion of the leaf spring portion 24 is in contact with the rear end surface of the motor 1, and the leaf spring portion 24 is curved and compressed in the axial direction. Accordingly, the first elastic member 21 is biased in a direction in which the rear end surface of the motor 1 and the bottom portion 10 are separated.

  Therefore, the leaf spring which is the first elastic member 21 urges the motor 1 toward the connection plate 53 and the reaction force of the leaf spring acts toward the bottom 10 side. The bottom portion 10 is fixed to the tube portion 9, and the tube portion 9 is fixed to the connection plate 53. The front end surface of the motor 1 is also fixed to the connection plate 53. Therefore, the urging force and reaction force of the leaf spring of the first elastic member 21 are received by the connection plate 53, and maintain an equilibrium state, and the motor 1 is maintained in a stable state. When the motor 1 vibrates due to the force based on the rotation of the motor 1 itself or the rotation of the pump 31, the force (load) applied to the leaf spring increases, so the urging force and reaction force of the leaf spring also increase. However, since the urging force and reaction force generated by the leaf spring are received by the connection plate 53, the urging force and reaction force are canceled by the connection plate 53 even when the force increases, and the motor 1 is in a stable state. Can be maintained.

  In the above state, when the motor 1 vibrates, a force (load) acts on the leaf spring due to the vibration, and the urging force and reaction force generated by the leaf spring increase, but the urging force and reaction force of the leaf spring are They cancel each other out, and the displacement of vibration can be kept small. Moreover, noise can be prevented by suppressing vibration.

As described above, in this example, for example, a member such as an anti-vibration rubber is disposed between the motor and the cover, and the vibration of the cover is suppressed by blocking the vibration of the motor from being transmitted to the cover. Unlike the conventional case in which this is the main function, the vibration of the motor is changed to the biasing force and reaction force of the spring by applying a biasing force (spring load) with a compression spring as an elastic member interposed, The main purpose is to dampen vibration by canceling both forces.
Thereby, vibration and noise can be suppressed more reliably than in the past.

5 to 7 show an electric pump according to a second embodiment of the present invention. FIG. 5 is a sectional view showing the electric pump according to the second embodiment. FIG. 6 shows the electric pump according to the second embodiment. FIG. 7 is a perspective view showing a second elastic member of the electric pump.
The electric pump according to the second embodiment is the electric pump according to the first embodiment, except that the first elastic member 21 is not provided as an elastic member, and the second elastic member 41 described later is provided. The same components as those of the electric pump of the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals, and the description thereof is omitted.

  Between the outer peripheral surface of the projecting portion 7 on the rear end surface of the motor 1 and the inner peripheral surface of the cylindrical projecting portion 16 (inner peripheral portion 17) of the bottom 10 of the motor cover 8, a second cylindrical elasticity is provided. The member 41 is arranged in a state compressed in the radial direction. The second elastic member 41 includes a cylindrical portion 42 formed in a short cylindrical shape, and a plurality of rectangular convex portions 43 that protrude from the cylindrical portion 42 to the outer peripheral side.

  The convex portion 43 is formed by bending the cylindrical portion 42 from the inside to the outside, is elastically deformable in the radial direction, and functions as a leaf spring. That is, a plurality of convex portions 43 functioning as leaf springs that generate a biasing force in the radial direction when compressed in the radial direction are arranged side by side in the circumferential direction. The rectangular convex portion 43 has a rectangular top plate along the circumferential direction of the cylindrical portion 42 and four surfaces substantially along the radial direction of the cylindrical portion 42 corresponding to the four sides of the top plate. However, when there are wall-shaped portions on these four surfaces, the wall portions adjacent to each other at the corners may be separated. Moreover, a wall-shaped member may exist only on two opposing surfaces of the four surfaces, and the remaining opposing back surfaces may be in an open state without any members.

  As described above, the second elastic member 41 is formed between the outer peripheral surface of the projecting portion 7 of the motor 1 and the inner peripheral surface of the cylindrical projecting portion 16 of the motor cover 8 with the convex portion 43 being compressed and deformed. The projecting portion 7 of the motor 1 is urged in the radial direction toward the central axis, and a reaction force generated by the second elastic member 41 is applied to the cylindrical projecting portion 16 of the motor cover 8. Acts radially outward. Similar to the first embodiment, the front end side of the motor 1 is fixed to the connection plate 53 of the mounting base 51. The bottom portion 10 is fixed to the tube portion 9, and the tube portion 9 is fixed to the connection plate 53. Therefore, the urging force and reaction force of the leaf spring of the second elastic member 41 receive a force at the connection plate 53 and maintain an equilibrium state. Thereby, the motor 1 is maintained in a stable state. When the motor 1 generates a force that vibrates in the radial direction due to the force based on the rotation of the motor 1 itself or the rotation of the pump 31, the force (load) applied to the leaf spring increases. Although increased, the urging force and reaction force generated by the leaf spring are received by the connection plate 53, so that the urging force and reaction force are offset and the motor 1 can be maintained in a stable state. . That is, the urging force and the reaction force generated by the leaf spring are increased by the radial force that generates the vibration, but these forces cancel each other and suppress the vibration.

  Further, as described above, the rear end portion of the motor 1 is urged in the axial direction of the motor shaft 2 in a state where the front end side of the motor 1 is attached to the mounting base 51. Vibration that causes the rear end of the motor 1 to swing around the front end can be suppressed by arranging the second elastic member 41.

  Another embodiment of the present invention may be configured to include both the first elastic member 21 and the second elastic member 41. Also with this configuration, vibration and noise of the motor 1 can be suppressed. The first elastic member 21 can suppress vibrations by being arranged in the axial direction between the motor 1 and the motor cover 8, and the second elastic member 41 includes the motor 1 and the motor cover 8. It is the structure which can suppress a vibration by arrange | positioning to radial direction between these. However, the present invention is not limited to this configuration, and other configurations may be used as long as the configuration is configured to attenuate the vibration by converting the force caused by the vibration into the biasing force and the reaction force of the spring and canceling each other's force.

  As described above, the elastic member is not a rubber-like member, but is preferably a compression spring that can generate an urging force even with slight elastic deformation, particularly a leaf spring (including a disc spring). By using a leaf spring, it can be arranged in a slight gap. The elastic member of the present invention is not a member intended to block vibration by absorbing vibration or letting it escape like various insulators such as conventional anti-vibration rubber. The purpose is to generate the above-mentioned reaction force by the elastic force generated by the above, and cancels the force that generates vibration.

DESCRIPTION OF SYMBOLS 1 Motor 8 Motor cover 21 1st elastic member 31 Pump 41 2nd elastic member 51 Mounting stand (support member)
53 Connection plate (support member)

Claims (3)

A pump,
A motor having a motor shaft coupled to the pump and driving the pump;
A support member that is disposed between the pump and a front end portion on the motor shaft side of the motor and supports the pump and the motor in a state where the motor shaft is penetrated;
A motor cover in which the open end side is fixed to the support member with a bottomed cylindrical shape covering the motor,
An elastic member in a compressed state is provided between the rear end of the motor and the bottom of the motor cover;
An electric pump, wherein the elastic member biases and supports the motor against the support member. As the elastic member,
A first elastic member in a compressed state along the axial direction of the motor shaft is provided;
The electric pump according to claim 1, wherein the motor is urged toward the support member along the axial direction of the motor shaft by the first elastic member. As the elastic member,
A second elastic member in a compressed state is provided along a radial direction about the motor shaft;
3. The electric pump according to claim 1, wherein the motor is urged along the radial direction by the second elastic member toward the motor shaft.

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