CN2107723U

CN2107723U - Motor brush device

Info

Publication number: CN2107723U
Application number: CN91208146U
Authority: CN
Inventors: 罗杰·F·贝恩斯
Original assignee: Johnson Electric Co ltd
Current assignee: Johnson Electric Co ltd; Johnson Electric SA
Priority date: 1990-05-21
Filing date: 1991-05-06
Publication date: 1992-06-17
Also published as: HK37395A; JP2945503B2; DE9106141U1; GB9011275D0; JPH05146108A; GB2244603A; GB2244603B

Abstract

An electric brush assembly component which is used for the fractional horsepower direct current motor bears two electric brushes 20 and 21 which are electrically connected in paralleled abreast and which are separately shaped. The structure reduces the effective electric current density of each electric brush body, whereas the size of the electric brush body is not enlarged. Simultaneously the dynamic characteristic of the electric brush body is not also influenced.

Description

Motor brush device

The utility model relates to the brush assembly of electric of motor.

In small size motor, the brush assembly of electric in fractional horse-power DC (PMDC) motor particularly, generally include a carbon brush on the end that is contained in a flexible conductive arm brush reed.The brush reed is provided with brush biasing is pressed against on the commutator on the motor reel.Brush assembly of electric generally is contained in one and has one for the bearing of motor reel setting and form on the end cap of a structure division of electric motor assembly.

In the low voltage application occasion, the all-in resistance of motor is more and more determined by the face that the connects resistance between brush and commutator.Because motor resistance is determined the maximum power scope that motor can be worked, therefore wish to reduce very much the face that the connects resistance of brush/commutator.

The purpose of this utility model is to provide a kind of electric electromechanics brush assemblies that effective brush/commutator connects face resistance that reduced.

According to the utility model, be provided with a kind of electric electromechanics brush assemblies that includes the elastic conduction supportive device, this elastic conduction supportive device is provided with supports two or more longitudinal axis with respect to motor to arrange vertically and the brush body that separately is shaped in parallel electric.

Supportive device generally comprises the discrete brush arm that promising each brush body is provided with.

Discrete brush arm can be arranged to have different natural resonance frequencies.

The brush body can be of different sizes with/or have different density.

According to one of the present utility model fractional horse-power DC motor example explanation in conjunction with the accompanying drawings, in the accompanying drawings with a brush assembly of electric:

Fig. 1 is isometric view motor, that partly broken of taking away end cap;

Fig. 2 is an end view of end cap inside, and brush assembly of electric is shown;

Fig. 3 is the side sectional view of the end cap of Fig. 2;

Fig. 4 is the top view of brush assembly of electric;

Fig. 5 is the end view of brush assembly of electric; With

Fig. 6 illustrates the view of another angle of the part of the brush of Fig. 5 and brush reed.

Referring to accompanying drawing, motor has an axle 10 that has a coiling armature 11 and commutator 12 in Fig. 1.Commutator 12 is longer than the commutator of the conventional motor of same specification in the axial direction.The end bearing 15 of two field magnets 14 and a bolster 10 is installed in the housing 13.

In Fig. 2 and Fig. 3, molded plastics end cap 16 is provided with a plastics brush clamp of supporting two pairs of brush arms.Every pair of brush arm includes a terminal part 17 that is connected to elastic brush supporter or brush reed 18 and 19.Brush 20 and 21 arranged apart vertically with respect to the longitudinal axis of motor, and be supported on the free end of corresponding brush reed.In use, brush is ordered about with commutator 12 contacts.

In Fig. 3 and Fig. 4, terminal 17 is fixed together by two groups of rivets 22 and 23 respectively with brush reed 18 and 19.Can adopt other fixed form, such as fixing with clip.Brush 20 and 21 top are located on

brush reed

18 and 19 in the close elongated slot at free-ended position through the processing (see figure 6) and being clamped in by interference fit respectively of being shaped.

Embodiment of the present utility model is provided with that wherein two or more brushes are installed side by side and the brush assembly of electric that uses in parallel electric.In other words, motor can have a general structure, can load onto or repack into a brush or two brushes in parallel for each brush assembly of electric at the assembling point.This just allows to maximally utilise the motor that public member adapts to different capabilities.Be used for higher power as motor, can be as in an embodiment form being shown with two (or a plurality of) brushes.

In the embodiment of improvement, the elastomeric material manufacturing that brush reed 18 is different with 19 usefulness or have different a little sizes makes each brush reed have different eigentones.For example make a groove therein between the two ends of a brush reed and reduce its effective elasticity.In other words, when the rotating speed of motor reel during corresponding to the resonance frequency of one of them brush reed, the brush that other reed holds on also can keep good contact with commutator.Another program, or additional conditions,

brush

20 and 21 has same overall dimension, they can be put in the onesize elongated slot of brush reed, but they is to make with the brush material of different densities.Brush also can be for same purpose has different overall dimensions, and the groove but same size is preferably made at the top with the common-use size on the brush reed is press-fitted.

As previously mentioned, embodiment of the present utility model can reduce and effectively connects face resistance, makes same winding resistance can carry big electric current so that higher stalling torque and electric current to be provided.Because two or more brushes are arranged, the current density that just need not improve each brush reaches this purpose.Thereby higher current density regular meeting increases the working life that consume reduces brush.In addition, the dynamic characteristic of each brush is different and can make inequalityly as described like that, therefore keeps perfect brush contact in certain range of speeds, need not increase the brush contact pressure and has reduced the working life of each brush.Avoided strengthening degenerating of intrinsic dynamic characteristic that brush brings simultaneously.Dynamic property is very important, because how much always little desirable the circularity of commutator is, and is in use to be to rotate under very high rotating speed.

Claims

1, a kind of electric electromechanics brush assemblies includes the elastic conduction supportive device, it is characterized in that this elastic conduction supportive device is provided with to support two or more longitudinal axis with respect to motor to arrange vertically and brush body in parallel, that separately be shaped electric.

2,, it is characterized in that supportive device comprises the discrete brush arm that promising each brush body is provided with by the brush assembly of electric of claim 1.

3,, one of it is characterized in that in discrete brush arm forming a groove that makes it to have the natural resonance frequency different with another arm by the brush assembly of electric of claim 2.

4, by the brush assembly of electric of claim 1,2 or 3, it is characterized in that the overall dimension of each brush body is inequality with the overall dimension of other brush body, make each brush have different eigentones.

5,, it is characterized in that each brush body has identical overall dimension but made by the material of different densities, makes each brush have different eigentones by the brush assembly of electric of claim 1,2 or 3.