JPS605731Y2 - small motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a small motor with two commutators connected to a rotor coil.

In a small motor equipped with two commutators, for example, one commutator is connected directly to the rotor coil, and the other commutator is connected to the rotor coil via a governor switch. When power is supplied by sliding the brush on one of the commutators, it rotates at a low speed at a constant speed determined by the governor switch, and when power is supplied by sliding the brush on one of the commutators, it rotates at high speed, so speed control can be performed.

Furthermore, the high-voltage coil of the rotor coil is connected to one commutator, and the low-voltage coil is connected to the other commutator, and the voltage applied to the brushes can be varied depending on which of the brushes in sliding contact with both commutators is supplied with power. small motors can be used even when the power supply voltages are different.

When two commutators are provided in this way, it is useful because the range of use of the small motor can be expanded.

There are two types of commutators: a cylindrical commutator in which curved segments are annularly provided around the rotor axis, and a flat commutator in which fan-shaped segments are annularly provided on a plane perpendicular to the rotor axis. The present invention aims to provide a compact motor that is easy to assemble and miniaturized by combining such commutators.One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a sectional view of a small motor. In this figure 1
The motor case consists of a cylindrical casing 2 with a bottom and a bracket 3 that covers the opening of the cylindrical casing 2.

An annular permanent magnet 4 is attached to the inner peripheral surface of the motor case 1, and a housing 2 serving as one inner end surface of the motor case 1 is attached.
A holding plate 7 is attached to the inner bottom surface 5 of the motor case 1. A holding plate 7 is provided with first power feeding brushes 6, 6 which are biased in the axial direction toward the center of the motor case 1.

In addition, the bracket 3 which becomes the other inner end surface of the motor case 1
On the inner surface 8 of the rotor shaft 9 there is a second
A feed brush 10.10 is installed.

A bearing LL provided at the center of the inner bottom surface 5 and the bracket 3
A rotor shaft 9 supported at a rotor shaft 12 includes a rotor 13, a rotor core 15 around which a rotor coil 14 is wound, a flat commutator 16 connected to the rotor coil 14, and a cylindrical commutator 1.
7 and a substrate 19 of the governor switch 18 are attached.

The flat commutator 16 is attached to the inner bottom surface 5 side of the rotor core 15 and comes into sliding contact with the first feed brushes 6, 6, and the cylindrical commutator ffi
,, -f 17 is attached to the bracket 3 side of the rotor core 15 and comes into sliding contact with the second power supply brush 10.10.

Further, a substrate 19 equipped with a governor block 18 is located between the flat commutator 16 and the end face of the rotor core 15, and by attaching the substrate 19 to the back surface of the flat commutator 16, the mechanical The strength of the dog is made into a dog.

Next, FIG. 2 shows an electric circuit diagram of a small motor, in which the rotor coil 14 includes three-phase coils 14a, 14b,
14c, the segment 16a of the flat commutator 16
is connected directly to the coil 14a (the governor switch G is connected directly to the coil 14a (the components 16b and 16e are the governor switch G in which resistors R, R2 are connected in parallel, respectively),
, G2 to the coils 14b and 14e.

In addition, each segment of the cylindrical commutator 17) 17a, 17b, 1
7e are directly connected to coils 14a, 14b, and 14e, respectively.

Resistors R1, R2 and governor switch G1. The G2 governor block 18 is configured.

[When assembling a small motor] 7, the rotor 1 is mounted so that the rotor shaft 9 is attached to the bearing 11 provided in the housing 2.
3 into the housing 2.

In this case, the inner bottom surface 5 of the casing 2 has first feeding brushes 6, 6 which are biased in the axial direction, and the flat commutator 16 is attached to the inner bottom surface 5 side of the rotor 13. , rotor 1
3 into the housing 2, the flat commutator 16 is in a state where it can come into sliding contact with the first power feeding brushes 6, 6.

Further, since the annular permanent magnet 4 is attached within the housing 2, when the rotor 13 is inserted into the housing 2, the rotor core 15 is attracted to the annular permanent magnet 4, and the inserted state of the rotor 13 is maintained.

Next, the second power supply brush 10 attached to the bracket 3.
The bracket 3 is expanded with the jig 20 between 10 and 10.
After fitting the bearing 12 to the rotor shaft 9 and fixing the bracket 3 to the opening edge of the housing 2 with the screw 21, the jig 20 is pulled out to release the expanded state between the power supply brushes 10 and 10. The second feed brush 10.10 is brought into contact with the cylindrical commutator 17 to complete the assembly.

However, when both commutators are cylindrical, there is a drawback that the axial direction of the small motor is skewed.

In addition, when both commutators are made into flat plates, the first power supply brush provided on the inner bottom surface 5 and the second power supply brush provided on the bracket 3 are both biased in the same axial direction, and each There is a drawback that it is difficult to uniformly adjust the contact pressure of each feed brush with respect to the commutator.

In contrast, in the present invention, the flat commutator 16 is provided on one end surface of the rotor 13, and the cylindrical commutator 17 is provided on the other end surface, so the size is smaller than when each commutator is made cylindrical. The axial length of the motor can be reduced, and since the first and second feed brushes that come into sliding contact with each commutator have different urging force directions, the contact pressure of each feed brush can be easily adjusted, making it compact and easy to assemble. Can easily provide a small motor.

Further, in the case where the motor case is constituted by a bottomed cylindrical case and a bracket that covers the opening thereof, and a first power supply brush that is in sliding contact with the flat commutator is provided on the inner bottom surface of the case, the motor case Since the rotor inserted into the bracket is attracted and held by a permanent magnet provided on the inner surface of the motor case, a jig is used to widen the space between the second power supply brushes provided on the inner surface of the bracket and biased in the radial direction. The bracket can be attached to the motor case in this state, making assembly easy.

[Brief explanation of the drawing]

The drawings show an embodiment of a small motor according to the present invention, and FIG. 1 is a sectional view of the small motor, and FIG. 2 is an electric circuit diagram of the small motor. 1... Motor case, 5... One inner end surface (inner bottom surface), 6, 6... First power supply brush,
8...Other inner end surface (inner surface), 10, 10...
...Second power supply brush, 13--Rotor, 1
4.14a, 14b, 14c... Rotor coil, 16... Flat commutator, 17... Cylindrical commutator, 2... Housing, 3...Bracket.

Claims (2)

[Scope of utility model registration request] (1) A first power supply brush biased in the axial direction is provided on one inner end surface of the motor case, and a second power supply brush biased in the radial direction is provided on the other inner end surface of the case, and A flat commutator connected to the rotor coil and in sliding contact with the first power supply brush is provided on the one inner end surface side of the rotor housed in the case, and a flat commutator is provided on the other inner end surface side of the rotor coil. The small motor is provided with a cylindrical commutator connected to the rotor coil and in sliding contact with the second power supply brush. (2) The motor case consists of a bottomed cylindrical casing and a bracket that covers the opening thereof, and the inner bottom surface of the casing is the one inner end surface, and the inner surface of the bracket is the other inner end surface. A small motor according to claim 1 of the utility model registration claim.