JP2004162541A - Electric brushless water pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress heat transfer to a circuit element having comparatively inferior heat resistance such as an electrolytic capacitor, and to improve connection reliability of a circuit to be used for a connection with an external power supply circuit, etc., in an electric brushless water pump. <P>SOLUTION: A circuit board 30 is held by a housing 10 and an end cover 20. An internal space is partitioned into a housing side internal space 13 and an end cover side internal space 23 by the circuit board 30. An electric connector 37 of a prescribed insertion/pull-out direction X is formed integrally with the circuit board 30 in a part projected from the internal space of the circuit board 30. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric brushless water pump, and more particularly, to an improvement of an electric part having a built-in brushless motor.
[0002]
[Prior art]
For example, an electric brushless water pump in which a brushless motor is built in a housing is known as an electric water pump used as an automobile part (Patent Document 1).
[0003]
This brushless motor is a kind of DC motor having a built-in control circuit for electronically performing position control instead of a contact portion such as a brush or a commutator.
(1) small electrical and mechanical noise;
(2) High reliability and long life
(3) High speed is easy,
(4) Speed control is easy,
It has the advantage of.
[0004]
Here, an example of the electric brushless water pump will be described based on a cross-sectional view shown in FIG. In addition, in the electric brushless water pump 100, only the pump portion such as the impeller 60 directly acting on the working fluid is schematically shown by a two-dot chain line, and the electric portion is shown by a solid line.
[0005]
The illustrated electric brushless water pump 100 is axially connected to the housing 10 so as to cover a substantially cylindrical housing 10 that houses a brushless motor 50 therein and one end surface 12 of the housing 10. The vehicle includes an end cover 20 and a circuit board 30 provided in the internal spaces 13 and 23 covered by the housing 10 and the end cover 20 and having a control circuit for controlling the brushless motor 50 formed thereon.
[0006]
Here, the end faces 12 and 22 of the peripheral walls 11 and 21 of the housing 10 and the end cover 20 abut each other.
[0007]
A gap is formed between the edge of the circuit board 30 and the inner surface of the peripheral wall 11 of the housing 10 and the inner surface of the peripheral wall 21 of the end cover 20.
[0008]
Therefore, the internal space 13 on the housing 10 side communicates with the internal space 23 on the end cover 20 side.
[0009]
The circuit board 30 includes a circuit element such as an electrolytic capacitor 31 as a power filter, and extends from an electric connector 37 connected to an external electric connector 200 for supplying external power supply and transmitting and receiving control signals and the like. The wiring 36 is soldered.
[0010]
The wiring 36 passes through the hole of the grommet 38 provided on the wall surface of the end cover 20 in a watertight manner, and is drawn out of the electric brushless water pump 100 to the outside.
[0011]
Further, a radiation fin 41 made of an aluminum alloy or the like for heat radiation is provided on the circuit board 30, and watertightness is maintained between the end cover 20 and the radiation fin 41 by a sealant (not shown).
[0012]
Further, the internal spaces 13 and 23 of the electric brushless water pump 100 are filled with a potting agent, so that heat H of the brushless motor 50 is easily transmitted to the peripheral walls 11 and 21 to enhance heat radiation performance.
[Patent Document 1]
JP 2001-295797 A
[Problems to be solved by the invention]
By the way, the heat generation H of the brushless motor 100 of the electric brushless water pump is large as described above, and this heat generation H is difficult to transfer to the power filter such as the electrolytic capacitor 31 on the circuit board 30. The circuit board 30 is provided on the surface opposite to the surface on the brushless motor 50 side, that is, on the surface on the end cover 20 side.
[0014]
However, since the internal space 13 on the housing 10 side communicates with the internal space 23 on the end cover 20 side, the heat generation H of the brushless motor 50 wraps around the internal space 23 on the end cover 20 side via the potting agent. And the electrolytic capacitor 31 and the like.
[0015]
Further, since the housing 10 and the end cover 20 are made of metal, heat is easily transferred as compared with resin or glass epoxy. However, heat H from the brushless motor 50 is first transmitted to the housing 10 which is located close to the brushless motor 50. Heat is transferred from the housing 10 to the end cover 20 via the end faces 12 and 22.
[0016]
Then, the heat transfer H ′ from the wall surface of the end cover 20 also transfers to the electrolytic capacitor 31 and the like.
[0017]
Therefore, the electrolytic capacitor 31 and the like in the conventional electric brushless water pump have a large thermal load, which is one of the causes of reducing the performance and life of the pump.
[0018]
In addition, the wiring 36 that has been drawn out through the grommet 38 is easily swung by the connection work of the electrical connectors 37 and 200 and subsequent vibrations, and the wiring 36 is fixed on the circuit board 30. The structure is such that a load is easily applied to the solder.
[0019]
For this reason, when a large load is applied to the wiring, solder cracks may occur, and the reliability of electrical connection may be reduced.
[0020]
The present invention has been made in view of the above circumstances, and suppresses heat transfer to a circuit element having relatively low heat resistance, such as an electrolytic capacitor, and has a connection reliability of a circuit used for connection to an external power supply circuit or the like. It is an object of the present invention to provide an electric brushless water pump that can improve the performance.
[0021]
[Means for Solving the Problems]
In order to solve the above problems, an electric brushless water pump according to the present invention includes a circuit board sandwiched between a housing and an end cover, and the circuit board partitions an internal space into a housing-side internal space and an end cover-side internal space. An electrical connector in a predetermined insertion / removal direction is formed integrally with a circuit board on a circuit board portion protruding from a space.
[0022]
That is, the electric brushless water pump according to claim 1 of the present invention is connected to the substantially cylindrical housing accommodating the brushless motor therein and the housing in the axial direction so as to cover one end surface of the housing. An electric brushless water pump including an end cover and a circuit board provided in an internal space covered by the housing and the end cover and on which a control circuit for controlling the brushless motor is formed, wherein the circuit board includes: The internal space is sandwiched between the front and rear surfaces of the circuit board by the peripheral wall end surface of the housing and the peripheral wall end surface of the end cover, and the internal space is partitioned into the internal space on the housing side and the internal space on the end cover side, Of the circuit board, protruded outside the housing and the end cover In addition, the electrical connector connected to the corresponding external electrical connector is formed integrally with the circuit board so that the insertion / removal direction of the electrical connector coincides with the holding direction of the circuit board between the housing and the end cover. It is characterized by having been done.
[0023]
Here, at least the end cover is made of metal, and the circuit board is made of non-metal having lower thermal conductivity than the end cover, for example, glass epoxy is used.
[0024]
According to the electric brushless water pump according to the first aspect of the present invention, the circuit board is sandwiched between the front and back surfaces of the circuit board by the peripheral wall end face of the housing and the end cover peripheral wall end face, and the inside of the circuit board is formed. Since the space is partitioned into an internal space on the housing side and an internal space on the end cover side, the heat generated by the brushless motor provided in the internal space on the housing side is different from the internal space on the housing side as in the related art. The heat is not transferred to the internal space on the end cover side through the communication part with the internal space on the end cover side, but is blocked by the circuit board serving as a partition, and the end cover side, which is the internal space on the end cover side The circuit element provided on the surface of the circuit board which faces the heat is difficult to conduct heat.
[0025]
Further, since the circuit board is sandwiched between the peripheral wall of the housing and the peripheral wall of the end cover, the housing and the end cover are not in direct contact with each other.
[0026]
Therefore, the heat from the peripheral wall of the housing is first transferred to the circuit board having lower thermal conductivity than the end cover, and then transferred from the circuit board to the end cover. Therefore, heat transfer from the end cover to the circuit element can be suppressed.
[0027]
An electric connector for connection to an external power supply or the like is provided on a portion of the circuit board sandwiched between the peripheral wall end surface of the housing and the end wall of the end cover, the portion protruding outside the housing and the end cover. Since the electrical connector is formed integrally with the board, the deflection of the electrical connector becomes the deflection of the circuit board itself, and the wiring of the electrical connector does not swing independently. There is no movement.
[0028]
Therefore, a load is not applied to the solder for fixing the wiring and the circuit board, and the connection reliability of a circuit used for connection to an external power supply circuit or the like can be improved.
[0029]
In addition, the electric connector formed integrally with the circuit board is formed such that the direction of insertion and withdrawal of the external electric connector to be connected (corresponding to) corresponds to the direction of holding the circuit board between the housing and the end cover. Therefore, the insertion / removal direction coincides with the die-removal direction of the board, and it is not necessary to use a special core or the like when molding the housing of the electrical connector, so that the manufacturing cost can be reduced.
[0030]
An electric brushless water pump according to a second aspect of the present invention is the electric brushless water pump according to the first aspect, wherein the circuit board is fastened together with the housing and the end cover.
[0031]
According to the electric brushless water pump according to the second aspect, the circuit board is fastened to the housing and the end cover sandwiching the circuit board, so that the housing and the end cover are fastened. At the same time, since the circuit board is also held between the housing and the end cover, the work efficiency of mounting the circuit board can be improved as compared with the case where the circuit board is separately fastened to the housing or the end cover.
[0032]
Further, as long as the tightening of the housing and the end cover is not loosened, the circuit board does not fall off from between the housing and the end cover, and the mounting reliability of the circuit board can be improved.
[0033]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, specific embodiments of an electric brushless water pump according to the present invention will be described with reference to the drawings.
[0034]
FIG. 1 is a longitudinal sectional view showing a schematic configuration of an electric brushless water pump according to one embodiment of the present invention.
[0035]
The illustrated electric brushless water pump 100 is axially connected to the housing 10 so as to cover a substantially cylindrical housing 10 that houses a brushless motor 50 therein and one end surface 12 of the housing 10. An end cover 20, a circuit board 30 provided in the housings 10 and the internal spaces 13 and 23 covered by the end cover 20 and provided with a control circuit for controlling the brushless motor 50, and a blade directly acting on a working fluid; And a pump unit such as a car 60.
[0036]
Note that the pump section of the electric brushless water pump 100 of the present embodiment is the same as the conventional one, and therefore only the outline is shown by a two-dot chain line for simplicity of illustration.
[0037]
The circuit board 30 is larger in size than the conventional circuit board, and its periphery is enlarged to the peripheral wall 11 of the housing 10 and the peripheral wall 21 of the end cover 20, and the peripheral edge is formed by another general flat portion 33 (see FIG. 2). The thickened portion 32 is formed to be thicker than that of FIG.
[0038]
The short cylindrical thickened portion 32 is sandwiched by the end surface 12 of the peripheral wall 11 of the housing 10 and the end surface 22 of the peripheral wall 21 of the end cover 20 from both the front and back surfaces of the circuit board 30.
[0039]
For this reason, the internal space 13 on the housing 10 side and the internal space 23 on the end cover 20 side are completely separated as two spaces by the circuit board 30. A circuit element such as an electrolytic capacitor 31 as a power filter is arranged on a surface of the end cover 20 on the side of the internal space 23.
[0040]
A part of the circuit board 30 is formed to protrude outside the housing 10 and the end cover 20, and an electric connector 37 connected to the corresponding external electric connector 200 is formed at the protruded part. ing.
[0041]
The electric connector 37 is formed such that the insertion / removal direction X with respect to the external electric connector 200 coincides with the direction in which the circuit board 30 is sandwiched between the housing 10 and the end cover 20, and one end of the electric connector 37 is on the circuit board 30. Are extended to the inside of the electrical connector 37 as contacts.
[0042]
More specifically, the circuit board 30 has a substantially rectangular window 34 formed at the center of the general plane portion 33, and includes a rectangular substrate 40 closing the window 34.
[0043]
The substrate 40 includes a substrate main body 42 and a radiating fin 41 made of aluminum alloy provided on the substrate main body 42. As shown in FIG. Are in contact.
[0044]
In addition, a sealing agent (not shown) is applied to a portion between the root portion of the heat dissipating fin 41 and the end cover 20 which is in contact with the fin 41 to maintain watertightness.
[0045]
Further, the housing 10 and the end cover 20 described above are made of metal, and the circuit board 30 including the board 40 (excluding the radiation fins 41) is made of glass epoxy having lower thermal conductivity than metal.
[0046]
As shown in FIG. 3, which is a cross section taken along line AA of FIG. 2, the circuit board 30 is formed by a screw member 70 passing through two through holes 32a formed in the short cylindrical thickened portion 32. The housing 10 and the end cover 20 are clamped together with the housing 10 and the end cover 20.
[0047]
Further, the internal spaces 13 and 23 of the electric brushless water pump 100 are filled with a potting agent to easily diffuse the heat H of the brushless motor 50 to the surroundings, thereby improving the heat radiation performance of the brushless motor 50.
[0048]
Next, the operation of the electric brushless water pump 100 according to the present embodiment will be described.
[0049]
First, in order to supply an external power supply to the electric connector 37 of the electric brushless water pump 100 and transmit and receive a signal for operation control of the electric brushless water pump 100, the power supply wiring and the transmission / reception wiring are provided. The connected external electric connector 200 is fitted in the direction of the arrow X, and these external wirings and the circuit board 30 of the electric brushless water pump 100 are electrically connected.
[0050]
At this time, a load for fitting is applied to the electric connector 37 in the direction of arrow X for connection with the external electric connector 200, but the electric connector 37 is formed integrally with the circuit board 30. Moreover, since the thickened portion 32, which is the root portion of the electric connector 37, is sandwiched between the housing 10 and the end cover 20, the rigidity of the electric connector 37 is high, and the No significant deformation occurs.
[0051]
Also, the wiring extending inside the electrical connector 37 does not cause relative displacement with respect to the circuit board 30.
[0052]
The brushless motor 50 is driven by the control of the circuit board 30 to which power is supplied, and the impeller 60 rotates. At this time, the brushless motor 50 generates heat.
[0053]
The heat H is transferred to the potting agent filled in the internal space 13 of the housing 10 and the potting agent is heated, but the circuit board 30 (including the board 40; the same applies hereinafter) is provided on the housing 10 side. Since the internal space 13 and the internal space 23 on the end cover 20 side are separated from each other, the heat H generated by the potting agent filled in the internal space 13 of the housing 10 is blocked by the circuit board 30 so that the electrolytic capacitor Heat is not easily transferred to the internal space 23 on the end cover 20 side, which is the internal space on the side where the circuit elements 31 and the like are disposed.
[0054]
Therefore, the amount of heat transferred to the circuit element via the potting agent is reduced as compared with the related art.
[0055]
Further, the heat H generated by the brushless motor 50 is also transmitted to the peripheral wall 11 of the housing 10 and is also transmitted to members in contact with the peripheral wall of the housing 10.
[0056]
Here, since the thickened portion 32 of the circuit board 30 is in direct contact with the end surface 12 of the peripheral wall 11 of the housing 10, the heat H is also transmitted from the peripheral wall of the housing 10 to the thickened portion 32. Since 30 is made of glass epoxy, the heat conductivity is not as high as that of the housing 10 and the end cover 20. Therefore, the amount of heat transferred to circuit elements such as the electrolytic capacitor 31 disposed on the general flat portion 33 of the circuit board 30 is small. , Relatively low.
[0057]
Since the thickened portion 32 is in contact with the end surface 22 of the peripheral wall 21 of the end cover 20, the amount of heat transferred from the thickened portion 32 to the end cover 20 is further reduced. The amount of heat transferred to the circuit element via the potting agent filled in the internal space 23 on the cover 20 side is significantly reduced as compared with a conventional electric brushless water pump.
[0058]
By the above operation, the amount of heat transferred to the circuit element such as the electrolytic capacitor 31 provided on the circuit board 30 is reduced as compared with the conventional case, and the heat load applied to the circuit element can be reduced.
[0059]
Therefore, the thermal load applied to the circuit element can be reduced as compared with the conventional electric brushless water pump, and the performance and life of the electric brushless water pump 100 can be suppressed from being reduced.
[0060]
Since the heat generated by the circuit element from the end cover 20 can be reduced, the end face of the end cover 20 may be closer to the capacitor 31 and the like than the conventional electric brushless water pump shown in FIG. As a result, the volume of the internal space 23 on the side of the end cover 20 can be reduced, and the manufacturing cost can be reduced by reducing the material cost for manufacturing the end cover 20 and the potting agent to be filled.
[0061]
Further, as described above, since the wiring extending inside the electrical connector 37 does not cause relative displacement with respect to the circuit board 30, a load is applied to the solder fixing the wiring and the circuit board 30. Therefore, connection reliability of a circuit used for connection to an external power supply power circuit or the like can be improved.
[0062]
The electrical connector 37 integrally formed with the circuit board 30 has an insertion / removal direction X with respect to the external electrical connector 200 to be connected which coincides with a direction in which the housing 10 and the end cover 20 sandwich the circuit board 30. Therefore, the insertion / extraction direction X coincides with the die / pull direction of the circuit board 30, and it is not necessary to use a special core or the like when molding the housing of the electrical connector 37. In addition, the manufacturing cost can be reduced.
[0063]
As described above, according to the electric brushless water pump 100 according to the present embodiment, heat transfer to circuit elements having relatively low heat resistance such as the electrolytic capacitor 31 is suppressed, and connection to an external power supply power circuit and the like is suppressed. The connection reliability of the circuit used can be improved.
[0064]
In the electric brushless water pump 100 according to the present embodiment, since the circuit board 30 is fastened together with the housing 10 and the end cover 20, the circuit board 30 is simultaneously fastened to the housing 10 and the end cover 20. Since the circuit board 30 is sandwiched between the housing 10 and the end cover 20, the work efficiency of mounting the circuit board 30 can be improved as compared with the case where the circuit board 30 is separately fastened to the housing 10 or the end cover 20.
[0065]
Further, as long as the tightening of the housing 10 and the end cover 20 is not loosened, the circuit board 30 does not fall off from between the housing 10 and the end cover 20, and the mounting reliability of the circuit board 30 can be improved. .
[0066]
【The invention's effect】
As described above, according to the electric brushless water pump according to the present invention, since the circuit board is partitioned into the housing-side internal space and the end cover-side internal space, the circuit board is separated from the brushless motor housed in the housing-side internal space. Heat generated by the circuit board is shielded by the circuit board, so that the heat insulation of the control circuit elements disposed on the end cover side surface of the circuit board is enhanced. Since the electrical connector in one direction is formed integrally with the board, the rigidity is improved, and the influence on the solder on the circuit board corresponding to the contact of the electrical connector can be reduced.
[0067]
That is, according to the electric brushless water pump according to claim 1 of the present invention, the circuit board is sandwiched between the front and back surfaces of the circuit board by the peripheral wall end surface of the housing and the end wall of the end cover, and the internal space is defined by the housing. Is divided into the internal space on the side of the housing and the internal space on the side of the end cover, so that the heat generated by the brushless motor provided in the internal space on the housing The circuit does not conduct heat to the internal space on the end cover side through the communication part with the internal space, but is shielded by the circuit board serving as a partition, and the circuit facing the end cover side, which is the internal space on the end cover side. Heat is not easily transferred to circuit elements provided on the substrate surface.
[0068]
Further, since the circuit board is sandwiched between the peripheral wall of the housing and the peripheral wall of the end cover, the housing and the end cover are not in direct contact with each other.
[0069]
Therefore, the heat from the peripheral wall of the housing is first transferred to the circuit board having lower thermal conductivity than the end cover, and then transferred from the circuit board to the end cover. Therefore, heat transfer from the end cover to the circuit element can be suppressed.
[0070]
In addition, an electrical connector for connection to an external power supply or the like is provided on a portion of the circuit board sandwiched between the peripheral wall end surface of the housing and the end wall of the end cover, the portion protruding outside the housing and the end cover. However, since the electric connector is formed integrally with the circuit board, the vibration of the electric connector becomes the vibration of the circuit board itself, and the wiring of the electric connector does not oscillate independently. There is no relative movement.
[0071]
Therefore, a load is not applied to the solder for fixing the wiring and the circuit board, and the connection reliability of a circuit used for connection to an external power supply circuit or the like can be improved.
[0072]
In addition, the electric connector formed integrally with the circuit board is formed such that the direction of insertion and withdrawal of the external electric connector to be connected (corresponding to) corresponds to the direction of holding the circuit board between the housing and the end cover. Therefore, the insertion / removal direction coincides with the die-removal direction of the board, and it is not necessary to use a special core or the like when molding the housing of the electrical connector, so that the manufacturing cost can be reduced.
[0073]
Further, according to the electric brushless water pump according to the second aspect of the present invention, since the circuit board is fastened to the housing and the end cover sandwiching the circuit board, the tightening of the housing and the end cover is performed. At the same time, since the circuit board is also sandwiched between the housing and the end cover, the work efficiency of mounting the circuit board can be improved as compared with the case where the circuit board is separately fastened to the housing or the end cover.
[0074]
Further, as long as the tightening of the housing and the end cover is not loosened, the circuit board does not fall off from between the housing and the end cover, and the mounting reliability of the circuit board can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a main part of an electric brushless water pump according to an embodiment of the present invention.
FIG. 2 is a diagram showing a circuit board of the electric brushless water pump shown in FIG.
FIG. 3 is a sectional view showing a section taken along line AA in FIG. 2;
FIG. 4 is a sectional view showing a main part of a conventional electric brushless water pump.
[Explanation of symbols]
Reference Signs List 10 Housing 11, 21, 32 Peripheral wall 12, 22 End face 13, 23 Internal space 20 End cover 30 First circuit board 31 Electrolytic capacitor 32 Thickened portion 32a Fastening hole 33, 42 Board body 34 Notch hole 36 Lead wire 37, 200 Electric connector 40 Second circuit board 41 Heat sink 50 Electromagnetic coil 60 Impeller 100 Electric brushless water pump H, H 'Heat

Claims (2)

A substantially cylindrical housing for housing the brushless motor therein, an end cover axially connected to the housing so as to cover one end surface of the housing, and an interior covered by the housing and the end cover. An electric brushless water pump comprising: a circuit board provided in a space, and a control circuit configured to control the brushless motor;
The substrate is sandwiched between the front and back surfaces of the substrate by a peripheral wall end surface of the housing and a peripheral wall end surface of the end cover, and the internal space is partitioned into an internal space on the housing side and an internal space on the end cover side. Together
An electrical connector connected to a corresponding external electrical connector is provided on a portion of the board that protrudes outside the housing and the end cover, and the insertion and removal direction of the electrical connector is such that the housing and the end cover sandwich the board. An electric brushless water pump, wherein the electric brushless water pump is formed integrally with the substrate so as to coincide with the direction. The electric brushless water pump according to claim 1, wherein the circuit board is fastened together with the housing and the end cover.

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