JP4382077B2 - Small motor - Google Patents

Description

  The present invention relates to a small motor used in an environment where inflow of grease or oil becomes a problem, an electrical equipment such as ABS using a small motor, or an electric tool.

  In recent years, small motors used for electrical equipment, electric tools, and the like are required to have high reliability while being further required to be smaller and lighter.

  FIG. 10 shows the structure of a conventional small motor. In FIG. 10, 1 is a small motor, 2 is a winding, 3 is an output shaft, 4 is an iron core, 5 is a brush, 6 and 11 are bearings, 7 is a commutator, 8 is a rotor, 9 is a yoke, and 10 is a bracket. , 12 is a brush holder, and 13 is a permanent magnet.

  The rotor 8 of the small motor 1 includes a substantially arc-shaped iron core 4 having a plurality of slots, a winding 2 wound and accommodated in the slot, and an output shaft 3 that is fixed through the center of the iron core 4 in the axial direction. The end of the winding 2 fixed to the output shaft 3 is composed of a commutator 7 electrically connected. The rotor 8 is covered with a yoke 9 having a bottomed hollow cylindrical shape in which the rotor 8 is rotatably accommodated and a plurality of permanent magnets 13 fixed to the inner peripheral surface. A bracket 10 is attached to the open end of the yoke 9 and closed. The small motor 1 having such a configuration includes a brush holder 12 inside the bracket 10, and slides with the commutator 7 by the brush 5 housed in the brush holder 12.

  However, in the above conventional configuration, when grease leaks from the output side bearing or oil from the counterpart device flows in, it may adhere to the commutator or brush and cause abnormal wear of the brush or performance degradation of the small motor. there were.

  An object of the present invention is to provide a small motor capable of obtaining high reliability against leakage of grease from an output side bearing or oil from a counterpart device.

  In order to solve the above problems, a small motor according to the present invention has a bracket or brush holder having a wall having a constant gap around the output shaft between the commutator and the bearing.

  This prevents grease leakage from the output side bearing or oil from the counterpart device from adhering to the commutator or brush, preventing abnormal brush wear and small motor performance degradation. Therefore, high reliability is obtained as a small motor used for such applications.

The first invention of the present application includes a substantially arc-shaped iron core having a plurality of slots, a winding wound and accommodated in the slot, an output shaft that is axially fixed through the center of the iron core, and A rotor composed of a commutator that is electrically connected to the ends of the windings fixed to the output shaft, and a plurality of permanent magnets on the inner peripheral surface in a bottomed hollow cylindrical shape that rotatably accommodates the rotor A case formed by adhering to the case, a bracket-shaped brush holder integrally formed so as to close the opening end of the case, and further arranged on the output side of the output shaft formed integrally with the brush holder. And a bearing housing that rotatably supports the rotor, and a brush that is disposed on the rotor side of the brush holder and is housed in the brush holder and slides on the commutator. Yes, and
The brush holder is provided with a wall having a certain gap around the output shaft between the commutator and the bearing, and is provided with a lack part in which a part of the housing is missing, and the lack part. A small motor having a configuration in which the arrangement of the brush in the housing is positioned on one side of line symmetry with respect to the center line of the output shaft, and the arrangement of the brush in the housing is positioned on the other side of line symmetry of the center line In the case of grease leakage from the output side bearing or oil from the counterpart device, it can be prevented from adhering to the commutator and brush, preventing abnormal wear of the brush and performance degradation of the small motor. Thus, a highly reliable small motor can be obtained.

A second invention of the present application, the shaft side end portion of the wall having a predetermined gap along the circumference of the shaft between the bearings and the commutator, compact structure in which a convex portion toward the bearing It is a motor and does not cross over the wall against the intrusion of oil etc., and does not flow into the small motor, preventing it from adhering to the commutator and brush, preventing abnormal wear of the brush and deterioration of the performance of the small motor It becomes possible and it has the effect that a highly reliable small motor can be obtained.

A third invention of the present application is a small motor having a configuration in which the brush holder of the first invention or the second invention lacks a part of the housing and is provided with a recess that leads to the missing part. When the amount of inflow into a small motor increases, it flows into the recess from the missing part, so it does not flow over the wall and into the small motor, preventing it from adhering to the commutator or brush, and abnormal brush wear In addition, it is possible to prevent the performance of a small motor from being deteriorated and to obtain a highly reliable small motor.

4th invention of this application is a small motor of the brush holder of 1st invention thru | or 3rd invention of the structure which has arrange | positioned the positional relationship of a brush and a recessed part to the line object with respect to the centerline of an output shaft. .

According to a fifth invention of the present application, in the brush holders of the first to fourth inventions, the housing at a position opposite to the center line of the output shaft with respect to the position of the missing portion of the housing is also lacked, so that a breathing hole is formed. It is the small motor of the provided structure .

  According to the invention according to the present application, since it has a wall having a certain gap along the circumference of the bearing between the commutator and the bearing, grease leakage from the output-side bearing or from the counterpart device When oil or the like flows in, it can be prevented from adhering to the commutator or the brush, and it is possible to prevent abnormal wear of the brush and a decrease in performance of the small motor, and a highly reliable small motor can be obtained.

  Further, by forming the wall integrally with the bracket or the brush holder, or by forming the bearing housing on the brush holder, the number of components of the small motor can be reduced.

  Furthermore, by providing a convex part toward the bearing at the axial end of the wall formed on the brush holder, an oil reservoir is formed on the outer periphery and outer periphery of the convex part by the housing of the bearing. Inflow of oil from the equipment can be prevented.

  Moreover, even if the amount of inflow into the small motor, such as oil, is increased by providing a lack part in a part of the housing of the bearing and forming a recess so as to be connected to the lack part, It is possible to promote the outflow by providing a breathing hole together with the lacking portion.

  In addition, it has a labyrinth shape with a fixed gap along the axis between the bearing and the commutator and a shaft that is fastened with the shaft or an integral wall between the bearing and mist at high temperatures. It is possible to prevent the oil from entering the oil.

In addition , a highly reliable apparatus can be obtained by using the small motor which has the said specific effect for apparatuses, such as an electrical equipment, such as an ABS apparatus, and an electric tool.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
A small motor according to a first embodiment of the present invention is shown in FIGS. 1, 2, and 3, reference numeral 14 denotes a wall, and the other reference numerals are the same as those in the conventional example (FIG. 10), and thus description thereof is omitted.

  The rotor 8 of the small motor 1 includes a substantially arc-shaped iron core 4 having a plurality of slots, a winding 2 wound and accommodated in the slot, and an output shaft 3 that is fixed through the center of the iron core 4 in the axial direction. The end of the winding 2 fixed to the output shaft 3 is composed of a commutator 7 electrically connected.

Then, the rotor 8 is covered with a case ( yoke 9 ) having a bottomed hollow cylindrical shape that rotatably accommodates a plurality of permanent magnets 13 fixed to the inner peripheral surface. A bracket 10 is attached to the open end of the case ( yoke 9 ) and closed.

  The small motor 1 having such a configuration includes a brush holder 12 inside the bracket 10, and slides with the commutator 7 by the brush 5 housed in the brush holder 12.

  On the other hand, by providing a wall 14 between the bearing 6 and the commutator 7, when grease leaks from the output-side bearing 6 or oil from the counterpart device flows in, it adheres to the commutator 7 or the brush 5. It is possible to prevent the abnormal wear of the brush 5 and the performance deterioration of the small motor 1, and a highly reliable small motor can be obtained.

  The wall 14 is formed integrally with the bracket 10 as shown in FIG. 1 or the brush holder 12 as shown in FIG.

  Further, as shown in FIG. 3, the bearing housing is integrally formed with the brush holder 12 having the wall 14, so that the number of parts can be reduced, and as shown in FIG. By providing the convex part 30 facing the bearing 6 at the shaft side end part, an oil sump 40 is formed on the outer periphery of the convex part 30 together with the bearing housing, and grease leakage from the output side bearing 6 or from the counterpart device When oil or the like flows in, it can be stored in the oil sump 40.

(Embodiment 2)
FIG. 5 shows a cross-sectional view of a small motor that is Embodiment 2 of the present invention. In FIG. 5, 12a is a lacking part in which a part of the housing is missing, 12b is a recess, and the other reference numerals are the same as those in the first embodiment (FIGS. 1 to 3) and the conventional example (FIG. 10). Description is omitted.

  The brush holder 12 is formed with a lacking portion 12a in which a part of the housing of the bearing 6 is missing, and is provided with a recess 12b that leads to the lacking portion 12a. When the amount of grease leakage from the output side bearing 6 or oil from the counterpart device increases into the small motor 1, it flows into the recess 12 b from the lacking portion 12 a and acts as if it is a reservoir tank. It is possible to prevent the brush 5 from adhering to the commutator 7 or the brush 5 without overflowing into the small motor, and to prevent abnormal wear of the brush 5 or performance deterioration of the small motor. It can be a motor.

  Furthermore, as shown in FIG. 6, by providing the breathing hole 50 in the housing separately from the lacking portion 12a, the flow into the concave portion 12b can be promoted.

  Even in the case where the convex portion 30 is provided and the oil reservoir 40 is formed, the oil or the like accumulated in the oil reservoir 40 flows from the lack portion 12a into the concave portion 12a.

  For mist-like oil at high temperatures, as shown in FIG. 7, the gap between the bearing 6 and the commutator 7 is between the wall 14 having a certain gap along the axis and the bearing 6. Intrusion can be prevented by forming a labyrinth shape in which a second wall 90 that is fastened to or integrated with the shaft is provided.

(Embodiment 3)
The ABS device using the small motor in the first embodiment or the second embodiment (system capable of preventing the tire from being locked during sudden braking) is attached to FIG. 8, and the ABS device shown in FIG. 8 is attached. An automobile is shown in FIG. In the ABS device shown in FIG. 8, the small motor shown in FIG. 5 is drawn.

  In recent years, ABS devices have been increasingly mounted on automobiles due to the increasing demand for safety in the market. For example, a small motor 70 such as grease used for the bearing 6 or other parts 80 constituting the ABS device 60 is used. Can be prevented from flowing into the interior.

  That is, the grease or the like to flow in flows from the gap 12a that is wider than the gap formed by the output shaft 3 and the wall 14, and accumulates in the recess 12b.

  Further, the positions of the brush 5 and the recess 12b are symmetrical with respect to the center line as shown in FIG. 5. For example, when the ABS 5 is attached to an automobile as shown in FIG. By attaching so as to be (see FIG. 5), the amount of oil or the like flowing into the small motor is abnormally large, overflowing from the recess 12b, and even if it flows into the small motor, it is prevented from adhering to the commutator or brush, Abnormal wear of the brush and performance degradation of the small motor can be prevented.

  Therefore, high reliability can be maintained for a long time in the ABS device shown in this embodiment.

  In the above description, the ABS device is taken as an example, but it is obvious that the same effect can be obtained in the power tool for the same reason.

  The present invention relates to grease leakage from an output-side bearing or a counterpart device regarding a small motor used in an environment where inflow of grease or oil or the like becomes an issue, an electrical equipment such as ABS using a small motor, or a power tool. This is to provide a solution to the problem caused by the inflow of oil.

Sectional drawing of the small motor which integrally formed the wall in the bracket of this invention Sectional drawing of the small motor which integrally formed the wall in the brush holder of this invention Sectional drawing of the small motor which formed the housing of the bearing integrally with the brush holder which formed the wall of this invention Sectional view of a small motor in which the oil sump of the present invention is formed Sectional view of a small motor with a lack and recess formed in the present invention Sectional view of a small motor with a breathing hole along with a lack of the present invention Sectional drawing of the small motor which comprises the labyrinth shape of this invention Sectional view of the ABS device of the present invention The perspective view of the motor vehicle carrying the ABS apparatus of this invention Cross section of a conventional small motor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Small motor 2 Winding 3 Output shaft 4 Iron core 5 Brush 6, 11 Bearing 7 Commutator 8 Rotor 9 Yoke 10 Bracket 12 Brush holder 12a Missing part 12b Recessed part 13 Permanent magnet 14 Wall 30 Protruding part 50 Breathing hole 60 ABS apparatus 90 Second wall

Claims (5)

A substantially arc-shaped iron core having a plurality of slots, a winding wound and housed in the slot, an output shaft fixed through the center of the iron core in the axial direction, and the winding fixed to the output shaft A rotor composed of a commutator electrically connected to the end of the rotor, a case in which a plurality of permanent magnets are fixed to an inner peripheral surface in a bottomed hollow cylindrical shape that rotatably accommodates the rotor, An integrally formed bracket-like brush holder mounted so as to close the open end of the case, and further formed integrally with the brush holder and disposed on the output side of the output shaft and rotatably supporting the rotor A bearing housing; and a brush disposed on the rotor side of the brush holder and housed in the brush holder and sliding with the commutator; and
The brush holder is provided with a wall having a certain gap around the output shaft between the commutator and the bearing, and is provided with a lack part in which a part of the housing is missing, and the lack part. A small motor having a configuration in which the arrangement of the brush in the housing is positioned on one side of line symmetry with respect to the center line of the output shaft, and the arrangement of the brush in the housing is positioned on the other side of line symmetry of the center line . In a miniature motor of the brush holder according to claim 1, wherein the axial end portion of the wall having a predetermined gap along the circumference of the shaft between the bearing and the commutator, provided with a convex portion toward the bearing structure small motor. In a miniature motor of the brush holder according to claim 1 or claim 2, small motor structure provided with recesses that lead to a lack portion of the housing. 4. The small motor brush holder according to claim 1, wherein the positional relationship between the brush and the recess is arranged on a line object with respect to the center line of the output shaft. 5. In a miniature motor of the brush holder according to any one of claims 1 to 4, provided with ventilation hole is lack other side position of the housing of the center line of the output shaft relative to the position of the lack of the housing structure small motor.

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