JP4253229B2 - Electric motor and electric pump using the same - Google Patents

Description

  The present invention relates to an electric motor and an electric pump including the electric motor.

  2. Description of the Related Art Conventionally, there is an electric pump configured by assembling a single motor and coupling it to the pump side. In order to provide a terminal for such an electric motor, as shown in FIG. 5A, a covering portion 101a for holding the terminal 102 is integrally formed on a brush device 101 provided with a brush pressed against a commutator of the electric motor. It is possible to do.

  However, when insert molding is performed so that the periphery of the terminal 102 is integrated with the brush device 101, the covering portion 101a is molded so as to be as small as possible due to the demand for a small physique, and as shown in FIG. In addition, the thickness of the covering portion 101a is reduced. As a result, as shown in FIG. 5 (c), the terminal 102 and the covering portion 101a are curved and deformed in the longitudinal direction along with the covering molding, and the terminal is made linear when the motor is assembled on the pump side. Or a member for holding a linear terminal is required.

  Further, due to the above-described request, in FIG. 5B, the width D of the covering portion 101a with respect to the width d of the terminal 102 is substantially the same (d≈D), and the terminal 102 is integrally formed with the brush device 101. In this case, the molding material may not flow between the end portion of the terminal 102 and the outer peripheral surface of the covering portion 101a. Then, the terminal 102 is exposed from the covering portion 101a, and there is a possibility that a short circuit occurs in a state where the electric motor is assembled on the pump side.

Therefore, one end of the terminal is insert-molded into the brush device, and the other end can be connected to an external power source through the pump hole formed in the pump part. What was comprised so that it might be hold | maintained is disclosed (refer patent document 1). In this electric pump, a terminal is inserted into a grommet which is a separate member from the brush device, whereby the terminal is held in a straight line and insulation is secured.
Japanese Patent No. 3027051

  However, in the conventional configuration, the terminal provided in the electric motor is not held in a straight line because the tip portion is unstable before being assembled on the pump side. For this reason, when assembling the terminal to the pump part, the dimensional accuracy on the tip side of the terminal is not ensured, and it takes time and labor for proper assembly, and a member (grommet) for holding the terminal in a straight line is required. There has been a problem of increasing the cost.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an electric motor capable of improving the dimensional accuracy of the electric motor while reducing the cost, and an electric pump using the electric motor. .

In order to solve the above problems, an electric motor according to claim 1 is provided with a rotor having a commutator fixed to an output shaft, a brush in contact with the commutator, one end side connected to the brush, and the other end side being An electric motor provided with a brush device provided with a plate-like power supply means connectable to an external power source, wherein the power supply means is coated and molded integrally with the brush device at the one end side; A recess portion extending along the same direction as the direction in which the power feeding means extends is formed in at least a part of the covered portion, and the power feeding means has an area of a cross section perpendicular to the axis along the extending direction in the axial direction. Are formed so that the cross-section of the recess is U-shaped or V-shaped, and the formation of the recess forms the recess in the direction in which the power feeding means extends. Part Wherein the width orthogonal to the axis is formed to be smaller than the width of the flat portion not formed of said recess.

According to a second aspect of the present invention, in the electric motor according to the first aspect, the portion of the brush device that covers the power supply means has a cylindrical shape having a diameter that can cover the other end side of the power supply means. It is characterized by being.

According to a third aspect of the present invention, in the electric motor according to the first or second aspect , the power feeding means extends in the same direction as the output shaft within an inner peripheral diameter of a motor yoke that houses the rotor. It is provided in the brush device.

According to a fourth aspect of the present invention, there is provided an electric pump according to any one of the first to third aspects, an eccentric cam portion provided on the output shaft and performing an eccentric motion, and an eccentric motion of the eccentric cam portion. An electric pump having a pumping unit assembled to the electric motor, having a pumping unit for pumping a fluid by a pump and a bearing unit that supports the output shaft, and a feeding path in which the feeding unit is disposed. And when the said electric motor is assembled | attached to the said pump part, the said electric power feeding means is accommodated in the said electric power feeding path | route, and penetrates the said pump part, It is characterized by the above-mentioned.

(Function)
According to the first aspect of the present invention, since the power feeding means is provided with the recess in the linearly extending direction, the rigidity is improved as compared with the case where the power feeding means remains flat. For this reason, it is possible to prevent the power supply means from falling or deforming when the power supply means is integrally formed with the brush device without increasing the number of components, and the dimensional accuracy of the brush device while reducing costs. Can be improved. Therefore, the assembling work when assembling the electric motor to another device can be easily and reliably performed.

Moreover , the area of the cross section orthogonal to the axis along the direction in which the power supply means extends is substantially the same along the axis. For this reason, in the part in which the hollow part of the electric power feeding means was formed, the distance from the edge part of an electric power feeding means to the outer periphery of a coating | coated part becomes large. As a result, the molding material flows smoothly into the outer periphery of the power feeding means when the covering portion of the recess is molded, so that the yield can be improved, insulation in the covering portion of the power feeding means is ensured, and the power feeding means is short-circuited (shorted). ) Can be prevented. In addition, since the cross-sectional area of the recess is substantially the same as the cross-sectional area of the other end connected to the external power supply, the current allowable amount is maintained and the energization amount can be reduced even if the recess is formed. There is no.

According to the invention described in claim 2 , in addition to the action of the invention described in claim 1, a distance from the end of the portion where the recess of the power feeding means is formed to the outer periphery of the covered portion is secured. The molding material flows smoothly into this part.

According to the invention described in claim 3 , in addition to the operation of the invention described in claim 1 or 2 , since the fitting direction of the output shaft of the motor and the power feeding means are both axial directions, the motor is assembled at the same time. The power feeding means can also be assembled, and the electric motor can be easily inserted. Further, the motor diameter can be made small.

According to the invention described in claim 4 , in addition to the action of the invention described in any one of claims 1 to 3 , in addition to assembling the electric motor to the pump unit, it is also possible to assemble the power feeding means. It becomes easy to insert the electric motor.

  ADVANTAGE OF THE INVENTION According to this invention, the dimensional accuracy of an electric motor can be improved, aiming at cost reduction.

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the electric pump 1 includes a motor unit 11 and a pump unit 12 as an electric motor.

  The motor unit 11 includes a bottomed cylindrical motor yoke 13, and an opening end of the motor unit 11 is fixed to a pump housing 25 described later via an O-ring 14 with a bolt 15. An arc-shaped magnet 16 is fixed to the inner peripheral surface of the motor yoke 13. Further, a rotor 17 is disposed at the shaft core portion in the motor yoke 13 so as to face the magnet 16.

  The rotor 17 includes a shaft 18 as an output shaft, and a commutator 19 is fixed to an intermediate portion in the axial direction. Further, a ball bearing 20 as a bearing portion is fixed by press-fitting to the other end portion in the axial direction of the shaft 18. An eccentric bearing 21 as an eccentric cam portion is fixed at a position adjacent to the ball bearing 20 (commutator 19 side). The eccentric bearing 21 includes a ball bearing 22 and an eccentric bush 23 press-fitted into the inner ring thereof, and the shaft 18 is press-fitted into an axial core portion of the eccentric bush 23 and fixed. Therefore, when the shaft 18 rotates, the eccentric bearing 21 moves eccentrically.

  Further, a support bearing 24 as a bearing portion is fixed by press-fitting between the eccentric bearing 21 and the commutator 19 at an intermediate portion in the axial direction of the shaft 18. The support bearing 24 will be further described in detail in relation to a brush device 26 described later.

  On the other hand, the pump unit 12 includes a pump housing 25, and the pump housing 25 is assembled to the motor unit 11.

  The pump housing 25 is formed with a receiving portion 28 into which the ball bearing 20 and the eccentric bearing 21 described above are inserted. The accommodating portion 28 has a substantially cylindrical shape with a reduced diameter at the tip, and the ball bearing 20 is closely fitted into the reduced diameter portion 28A. Therefore, in the inserted state, the tip end portion of the shaft 18 is pivotally supported. In addition, an eccentric bearing 21 is disposed in the center of the enlarged diameter portion 28B of the accommodating portion 28 so as to be capable of eccentric movement.

  A part of the outer peripheral surface of the eccentric bearing 21 is in contact with a plunger 30 that is closely accommodated and arranged in a plunger support 29 so as to be able to reciprocate. A flow path is formed in the central portion of the plunger 30 so that oil can flow in. Further, the plunger 30 itself is pressed and urged by the compression coil spring 31, and a check ball 33 pressed and urged by the compression coil spring 32 is in contact with the lower end portion in the axial direction so as to be separated. Further, another check ball 34 is pressed and urged by a compression coil spring 35 at a position facing the check ball 33, and the check balls 33 and 34 constitute a check valve.

  Accordingly, when the eccentric bearing 21 is eccentrically moved, the plunger 30 is reciprocated to open or close the check balls 33 and 34, thereby causing the oil pressure feeding suction hole 36 and the discharge hole 37 formed in the pump housing 25. Oil is inhaled and discharged. The plunger 30, the check balls 33 and 34, the suction hole 36, and the discharge hole 37 described above correspond to a pressure feeding unit.

  Further, in the pump housing 25, a pump hole 25 a is formed in the axial direction of the shaft 18 slightly above the eccentric bearing 21 in the state shown in FIG. 1. A holding portion 38 of the brush device 26 described later is accommodated in the pump hole 25a, and one end portion of the wiring / use plate 39 embedded in the holding portion 38 is connected to the pump housing 25 as shown in FIG. It is exposed from the left side.

  On the other hand, as shown in FIGS. 2A and 2B, the holder housing 27 of the brush device 26 has a ring shape in which a through hole 40 is formed at the center, and is tightly attached to the brush device 26. The bolt 42 is screwed into the collar 41 in this state. A ground terminal 47 connected to the commutator 19 of the motor unit 11 is fastened to the bolt 42 together.

  On the surface of the holder housing 27 (the rotor 17 side in the state shown in FIG. 1), four-pole brushes 43, 44, 45, 46 are radially arranged at equal intervals in the circumferential direction. These brushes 43, 44, 45, 46 are always urged toward the center of the through hole 40, and the tip of each brush is the periphery of the through hole 40 before the shaft 18 penetrates the through hole 40. It is in a state protruding slightly. In addition, pigtails 43A, 44A, 45A, and 46A extend from the upper end surface of each brush.

  A holding portion 38 is formed on the surface of the holder housing 27 opposite to the side on which the brushes 43, 44, 45, 46 are provided, and the holding portion 38 has a wiring combined plate 39 as a power feeding means. Is embedded with insulating resin by insert molding.

  As shown in FIG. 3 (a), the wiring combined plate 39 is provided at the substantially central portion in the width direction of the one end side (left side in the figure) embedded in the holding portion 38, as shown in FIG. A recess 39a having a U-shaped cross section is formed. The recess 39a is formed so as to extend in the same direction as the direction in which the wiring / combination plate 39 extends, and is substantially in the axial direction (longitudinal direction) in the portion covered with the holding part 38 of the wiring / combination plate 39. It is formed over the entire area. The other end side of the wiring / use plate 39 is exposed from the holding portion 38 and has a flat plate shape. In addition, the area of the cross section orthogonal to the axial direction along the direction in which the wiring combined plate 39 extends is substantially the same along the coaxial line direction. That is, in the wiring / use plate 39, the portion where the recess 39a is formed (one end side) and the portion where the recess 39a is not formed (the other end side) have substantially the same cross-sectional area. Thus, the one end side of the wiring / use plate 39 is connected to the commutator 19 via the brushes 43, 44, 45, 46, and the other end side can be connected to an external power source. Thus, since the wiring combined plate 39 is formed with the recessed portion 39a along the longitudinal direction, the rigidity is improved, and the linear state is maintained as shown in FIG.

  In addition, a pair of protrusions 48 are erected on the surface of the holder housing 27 on which the brushes 43, 44, 45, 46 are provided, and a noise prevention capacitor 49 is sandwiched between the protrusions 48. ing.

  A cylindrical bearing holding portion 50 is formed integrally with the pump housing 25 on the surface of the holder housing 27 on which the holding portion 38 is provided. A support bearing 24 that pivotally supports an intermediate portion in the axial direction is held and fixed by press-fitting.

  Next, a procedure for assembling the motor unit 11 to the pump unit 12 will be described.

  As a pre-stage of this assembling operation, the wiring / use plate 39 is insert-molded in the holding portion 38 of the holder housing 27 of the brush device 26. At this time, as shown in FIG. 3 (a), since the recessed portion 39a is formed in the portion covered with the holding portion 38, the wiring / use plate 39 is not deformed in the longitudinal direction. Therefore, the wiring / use plate 39 is integrally formed with the brush device 26 in a state in which the wiring / use plate 39 is kept linear in the axial direction (the axial direction of the shaft 18).

  In addition, since the holding portion 38 has a cylindrical shape having a diameter that can accommodate the portion exposed from the holding portion 38 of the wiring / use plate 39 (the portion on the other end side), in the portion where the recess 39a is formed. A distance is ensured between the end of the recessed portion 39a and the outer peripheral surface of the holding portion 38, and the molding material surely flows into this portion. For this reason, the yield of the brush device 26 is improved, and the insulation of the wiring / use plate 39 is reliably ensured. Further, by securing the distance, the wiring / use plate 39 is stably fixed to the brush device 26.

  First, a commutator 19 is fixed to an intermediate portion of the shaft 18 of the rotor 17. In parallel with this, brushes 43, 44, 45, and 46 are attached to the surface of the holder housing 27 in which the wiring-use plate 39 is embedded by insert molding as described above, and the pigtails 43A, 44A, 45A, and 46A are connected. Work is done. Further, the support bearing 24 is press-fitted into the bearing holding portion 50, and the capacitor 49 is mounted. Thus, the brush device 26 is assembled.

  Next, the brush device 26 is assembled to the intermediate portion of the shaft 18 in the axial direction. That is, the brushes 43, 44, 45, 46 in a slightly protruding state are pushed in the direction opposite to the direction in which they are urged (the radially outward direction of the rotor 17). A shaft 18 is inserted into the shaft 40 from its tip. Then, the support bearing 24 is pivotally supported by the intermediate portion in the axial direction of the shaft 18. Then, coil springs and caps are fitted from behind the brushes 43, 44, 45, 46, and the brushes 43, 44, 45, 46 are pressed against the commutator 19. Thereafter, the eccentric bearing 21 and the ball bearing 20 are mounted in this order.

  Next, while inserting one end portion in the longitudinal direction of the wiring / use plate 39, that is, the end portion not fixed to the holder housing 27, into the pump hole 25 a as a power feeding path formed in the pump housing 25, The part 11 is fitted to the pump part 12. At this time, since the holding portion 38 that is integrally formed with the brush device 26 by inserting the wiring / use plate 39 is held linearly in the same axial direction as the shaft 18, the holding portion 38 (wiring / use plate 39) is easy. The pump housing 25 can be inserted into the pump hole 25a. At this time, the ball bearing 20 is press-fitted into the reduced diameter portion 28 </ b> A of the accommodating portion 28 of the pump housing 25. Next, in this state, the bolt 42 is screwed into the collar 41 and the brush device 26 is assembled to the pump housing 25. Thereafter, the motor yoke 13 is fitted through the O-ring 14 and assembled to the pump housing 25 with the bolt 15. In the state after the assembly is completed, the shaft 18 is cantilevered by the ball bearing 20 and the support bearing 24.

  Next, the operation of the electric pump 1 will be described.

  When power is supplied through the wiring / use plate 39 and the brushes 43, 44, 45, 46, the shaft 18 rotates. Thereby, the eccentric bearing 21 moves eccentrically. For this reason, the plunger 30 in contact with a part of the peripheral surface of the eccentric bearing 21 reciprocates. Accordingly, the check balls 33 and 34 are regularly opened / closed, and oil is sucked and discharged from the suction hole 36 and the discharge hole 37.

  Next, characteristic effects of the present embodiment will be described.

  (1) In the present embodiment, the wiring / use plate 39 of the motor unit 11 is integrally coated and formed at one end side with the brush device 26 and extends at least partially along the same direction as the direction in which the wiring / use plate 39 extends. A recess 39a is formed. As described above, the wiring-use plate 39 is provided with the recess 39a in the linearly extending direction, so that the rigidity is improved as compared with the case where the plate is used as a flat plate. For this reason, it is possible to prevent the wiring / use plate 39 from falling or deforming when the wiring / use plate 39 is integrally formed with the brush device 26 without increasing the number of components. The dimensional accuracy can be improved. Therefore, the assembling work when assembling the motor unit 11 to another device (pump unit 12) can be easily and reliably performed.

  (2) In the present embodiment, the area of the cross section perpendicular to the axis along the direction in which the wiring / use plate 39 extends is substantially the same along the axis. For this reason, the recess 39a of the wiring / use plate 39 has substantially the same cross-sectional area as the flat plate portion where the recess 39a is not formed. Accordingly, the distance from the end of the recessed portion 39a of the wiring / use plate 39 to the outer periphery of the holding portion 38 is increased, so that the molding material smoothly flows when forming this portion, and the insulation of the covering portion of the wiring / use plate 39 is insulated. Is ensured, and the occurrence of a short circuit of the wiring / use plate 39 can be prevented. In addition, the yield can be improved. Furthermore, since the cross-sectional area of the recess 39a is substantially the same as the cross-sectional area on the other end side to which the external power supply is connected, the current allowable amount is maintained and the energization amount is not reduced.

  (3) In this embodiment, the portion of the brush device 26 that covers the wiring / use plate 39, that is, the holding portion 38 has a cylindrical shape having a diameter that can cover the other end of the wiring / use plate 39. For this reason, the distance from the end of the wiring / use plate 39 to the outer periphery of the covered portion (holding portion 38) is increased, and the molding material flows smoothly into this portion. Therefore, the moldability of the holding part 38 is improved.

  (4) In the present embodiment, the wiring / use plate 39 is provided so as to extend in the same direction as the shaft 18 within the inner peripheral diameter of the motor yoke 13 that houses the rotor 17. For this reason, since the fitting direction of the shaft 18 of the motor unit 11 and the wiring / combination plate 39 are both axial directions, the wiring / combination plate 39 can be assembled at the same time as the motor unit 11 is assembled, and the motor unit 11 is connected to the pump unit 12. Insertion is easy. Moreover, the diameter of the electric pump 1 can be made small.

  (5) In the present embodiment, the electric pump 1 includes a motor unit 11 and a pump unit 12. The pump unit 12 is provided with an eccentric bearing 21 provided on the shaft 18, and a pumping means (plunger 30, check balls 33 and 34, suction hole 36 and discharge hole 37) that pumps fluid by the eccentric motion of the eccentric bearing 21. A ball bearing 22 that supports the shaft 18 and a support bearing 24 are provided. In addition, a pump hole 25a in which the wiring / use plate 39 is disposed is formed. When the motor unit 11 is assembled to the pump unit 12, the wiring / use plate 39 is accommodated in the pump hole 25 a and penetrates the pump unit 12. For this reason, the wiring portion plate 39 can be assembled at the same time as the motor portion 11 is assembled to the pump portion 12, and the motor portion 11 can be easily inserted. In addition, since the wiring-use plate 39 penetrates the pump portion 12 within the inner peripheral diameter of the motor yoke 13, the electric pump 1 can be reduced in size.

  In addition, you may change embodiment of this invention as follows.

  In the above embodiment, the cross-sectional shape of the recessed portion 39a formed in the wiring-use plate is U-shaped, but the cross-sectional shape of the recessed portion is not limited to the U-shape. For example, a recess 39b having a V-shaped cross section provided at the center in the width direction as shown in FIG. 4 (a), or a cross section formed over the entire width direction as shown in FIG. 4 (b). It is good also as the V-shaped hollow part 39c.

  In the present embodiment, the portion inserted into the holding portion 38 of the wiring-use plate 39 has the depression 39a formed over almost the entire area in the longitudinal direction, but the depression 39a is not provided over the entire area in this way. Also good. That is, if the rigidity can be ensured while being covered with the holding portion 38, the recessed portion 39 a may be formed in at least a part of the portion inserted into the holding portion 38.

  In this embodiment, the cross-sectional area of the portion where the recess 39a of the wiring / use plate 39 is formed is the same as the cross-sectional area on the other end side of the wiring / use plate 39. If the distance between the outer peripheral surface of the portion 38 is secured, the cross-sectional area may be larger than this. Then, the energization amount of the wiring / use plate 39 is surely ensured.

  -In this embodiment, although the holding | maintenance part 38 was made into the column shape, it does not need to be a column shape. For example, a flat shape along the wiring / use plate 39 may be used.

  In the present embodiment, the wiring combined plate 39 has the same direction as the shaft 18 within the inner peripheral diameter of the motor yoke 13 as the longitudinal direction. However, the mode in which the wiring combined plate 39 is provided in the motor unit 11 is this. It is not limited at all. For example, the wiring / use plate 39 may be provided such that the direction perpendicular to the shaft 18 is the longitudinal direction.

  -In this embodiment, although the motor part 11 was assembled | attached to the pump part 12 and the electric pump 1 was comprised, you may assemble | attach the motor part 11 to another apparatus.

  The technical idea that can be grasped from each of the above embodiments will be described below.

(B) the cross-sectional area of the front Symbol recess is you being greater than the cross-sectional area of the other end. Thereby, it can prevent reliably that the electric current which flows into an electric power feeding means reduces.

Sectional drawing of the electric pump of one Embodiment. (A) is a top view of a brush apparatus, (b) is the sectional view on the AA line of (a). (A) is a partial sectional view of the brush device, (b) is a sectional view taken along the line BB of (a), and (c) is a sectional view taken along the line CC of (a). (A), (b) is a partial cross section figure of the brush device of another example. (A), (b) and (c) are explanatory drawings of the conventional terminal shape.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electric pump, 11 ... Motor part (electric motor), 12 ... Pump part, 13 ... Motor yoke, 17 ... Rotor, 18 ... Shaft (output shaft), 19 ... Commutator, 21 ... Eccentric bearing (eccentric cam part) , 26 ... brush device, 30 ... plunger (pressure feeding means), 33, 34 ... check ball (pressure feeding means), 36 ... suction hole (pressure feeding means), 37 ... discharge hole (pressure feeding means), 43, 44, 45, 46 ... Brush, 38 ... Holding part (part covering power supply means), 38a ... Pump hole (power supply path), 39 ... Plate-combining plate (power supply means), 39a, 39b, 39c ... Depression part

Claims (4)

A rotor having a commutator fixed to the output shaft;
An electric motor comprising: a brush that is in contact with the commutator; and a brush device provided with a plate-like power supply unit that is connected to an external power source at one end and is connected to the brush at the other end;
The power supply means has one end side integrally formed with the brush device, and a recess extending along the same direction as the direction of the power supply means is formed in at least a part of the covered part ,
The power feeding means is formed such that the cross-sectional area orthogonal to the axis along the extending direction is substantially the same along the axial direction, and the cross-section of the recess is U-shaped or V-shaped, By forming the recess, the width of the portion where the recess is formed in the extending direction of the power feeding means is formed so as to be smaller than the width of the flat plate portion where the recess is not formed. An electric motor characterized by being made . 2. The electric motor according to claim 1, wherein a portion of the brush device that covers the power supply unit has a cylindrical shape having a diameter that can cover the other end side of the power supply unit. . 3. The electric motor according to claim 1, wherein the power feeding unit is provided in the brush device so as to extend in the same direction as the output shaft within an inner peripheral diameter of a motor yoke that houses the rotor. An electric motor characterized by that. The electric motor according to any one of claims 1 to 3,
An eccentric cam portion that is provided on the output shaft and moves eccentrically, a pressure feeding means that pumps fluid by the eccentric movement of the eccentric cam portion, and a bearing portion that pivotally supports the output shaft and the power feeding means are disposed. A pump unit assembled with the electric motor, in which a power supply path is formed;
An electric pump comprising:
When the electric motor is assembled to the pump part, the electric power feeding means is accommodated in the electric power feeding path and penetrates the pump part.

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