CN1046062C

CN1046062C - Miniature motor

Info

Publication number: CN1046062C
Application number: CN95106428A
Authority: CN
Inventors: 佐谷务; 中桥宏明
Original assignee: Mabuchi Motor Co Ltd
Current assignee: Mabuchi Motor Co Ltd
Priority date: 1994-05-25
Filing date: 1995-05-25
Publication date: 1999-10-27
Anticipated expiration: 2015-05-25
Also published as: JPH07322552A; CN1118532A

Abstract

To enhance the hermetic sealing performance without machining the fixing face while preventing intrusion of water, oil, etc., by applying a packing, made of a flexible elastic material, into a groove made in the outer end face of an end cap. A groove 16 is made substantially in phi-shape around output shafts 13a, 13 while covering the periphery of a fixing bolt hole 26. Four positioning holes 17 are made in the groove 16 and four arcuate recesses 18 are made on the outside of the recess 16 thus forming a rib-like protrusion 19 contiguously to the recess 16. When another arcuate recess 18 is made at the outer end of an end cap 6, an arcuate protrusion is formed on the corresponding inner end face and a coaxial setting is ensured when the outer periphery of the protrusion is engaged with the inner peripheral face at the opening in the housing. When a miniature motor is fixed to an external machine, a packing is set in the recess 16 of the cap 6 which is then fastened. This structure prevents the intrusion of water, oil, etc., into the inner space and facilitates the assembling work.

Description

Electrical micro-machine

Present invention relates in general to for example be used for the electrical micro-machine of driving machine motor-car electricity parts, water pump etc., more specifically to a kind of like this electrical micro-machine, the inner space that it will hold the rotor that comprises armature core, commutator etc. seals, anti-sealing, wet goods enter motor interior, and are easy to assembling.

Fig. 1 is the axial orthogonal view of the electrical micro-machine of general type.In Fig. 1, the shell that reference number 1 expression is made by the such metal material of for example mild steel, and make the hollow cup-shaped of the end, for example the permanent magnet 2 of segmental arc is installed on the inner peripheral surface of shell securely by binding material such as adhesive.Permanent magnet 2 can be made hollow cup-shaped, is magnetized at a plurality of magnetic poles of its inner peripheral surface.

In shell 1, provide and had in the face of the armature core 3 of permanent magnet 2 and the rotor 5 of commutator 4.The end cap that reference number 6 expressions are made by the metal material that is similar to shell 1, it is assembled to the opening end of shell 1.The stand base that reference number 7 expression is made by the such insulating material of for example resin is assembled to the opening end of shell 1 with end cap 6.

The brush that reference number 8 expressions are made by the such electric conducting material of for example carbon, for example do quadrangularly, and be assembled to slidably on the brush carriage 9, it is cup-shaped that brush carriage 9 is made hollow side, and be formed on the inner face of stand base 7, make the outer peripheral face sliding contact of brush and commutator 4.Prestrain helical spring in the reference number 10 expression brush carriages 9 makes brush 8 press to commutator 4.

Reference number 11 expressions connect the lead-in wire of the conductive component (not shown) on the stand base 7, are used for the electric energy from the external dc power (not shown) is delivered to commutator 4 through brush 8.Reference number 12 expression bearings; Pair of bearings 12 is assembled to the bottom (not shown) of shell and the middle body of end cap 6 securely, so that support the axle 13 that constitutes rotor 5 rotatably.Axle 13 is protruding from the bottom of shell 1.

Utilize said structure, when the commutator 4 of power supply by the conductive component on the stand base 7, brush and formation rotor 5 from going between 11 when delivering to rotor 5, revolving force is applied on the rotor that is arranged in magnetic field, this magnetic field is to be produced by the permanent magnet on the inner peripheral surface that is fixedly mounted in shell 12, this makes rotor 5 rotate, by outwardly directed axle 13 drives the external equipment (not shown) from the bottom of shell 1.

When with the electric parts of the electrical micro-machine drive installation with said structure in the such adverse circumstances of for example starting motor-driven vehicle unit room; side at the end cap 6 of shell 1 usually also provides waterproof cover 14, to prevent owing to water, wet goods infiltrate undesirable accident that the inner space of shell 1 causes.This waterproof cover 14 is made by for example elastomeric material usually, makes the hollow cup-shaped of the end, and its internal diameter equals the external diameter of shell 1 substantially.Owing in the bottom of shell 1 a bearing (not shown) is arranged, so need be similar to the sealing device of the opening end that is used for shell 1.Yet adopt a device that separates to be communicated with jockey in fact usually and connect external equipment together.

When the electrical micro-machine of the general type that will have said structure is installed to external equipment, generally adopt at the through bolt that axially passes shell 1 inside.For through bolt is installed, must temporarily remove waterproof cover 14 from shell 1.Utilizing after through bolt is installed in electrical micro-machine on the external equipment, waterproof cover 14 must relay the opening end at shell 1.Consequently operating efficiency is lower.

In that being installed on the shell 1 or from shell 1, waterproof cover 14 removes the process of waterproof cover 14, or utilizing through bolt electrical micro-machine to be installed in the process on the external equipment, owing to may damage waterproof cover 14 because of carelessness, weaken waterproof and grease proofing sealing and reliability.

In addition, cover on the opening end of shell 1, together with end cap 6 owing to waterproof cover 14 so the axial length of whole electrical micro-machine has extended inevitably.Also have the size of waterproof cover 14 also to become greatly, this has improved manufacturing cost.

When the electrical micro-machine that will have said structure was installed on the external equipment, the outer face of shell 1 bottom was as installed surface 15.Water, wet goods may infiltrate the inner space of shell 1 by installed surface 15 and the bearing (not shown) that provides in the bottom of shell 1.

In order to address this problem, by installed surface 15 being carried out machining to improve its fineness or to reduce its surface roughness and improve sealing.Yet do the time that means machining and the increase in man-hour like this.In addition, owing to, do to guarantee extraordinary sealing like this improving suffered restriction aspect the sealing.

The present invention is intended to solve problem intrinsic in the prior art, an object of the present invention is to provide and a kind ofly can prevent that sealing, wet goods enter the electrical micro-machine of the inner space that holds rotor, and under need not, improve sealing the situation of motor mounting being carried out machining to the installed surface on the external equipment.

In order to realize these purposes, according to the invention provides a kind of electrical micro-machine, it comprises the shell with the permanent magnet that is assembled to inner circumferential surface securely, rotor with armature core and commutator, stand base with brush, with the end cap that is assembled to an opening end of shell, the output shaft of its rotor passes end cap and protruding, be formed with a groove in the outer face of end cap, around the construction bolt hole on encirclement output shaft and the topped end cap, and the sealing gasket of being made by a kind of flexible, flexible material is placed in the groove.

Fig. 1 is the axial front part sectioned view of the electrical micro-machine of general type.

Fig. 2 to 5 is front view, right side view, left side view and axial part sectioned views of one embodiment of the present of invention.

Fig. 6 and 7 is plane graph and the profiles that are used for the sealing gasket of one embodiment of the present of invention.

Fig. 8 is that the expression sealing gasket is installed in the part sectioned view that embodies the state in the electrical micro-machine of the present invention.

Fig. 2 to 5 is front view, right side view, left side view and the axial part sectioned views that embody electrical micro-machine of the present invention.The part identical with Fig. 1 represented with identical reference number.In Fig. 2 to Fig. 5, reference number 21 expressions are along the edge and the end cap 6 integrally formed curved edges of end cap 6.Part at curved edge 21 is formed with interlock pawl 22, for example relative 180 ° of its

position.Interlock pawl

22 and 22 bendings are with the outer recess of placing 23 and 23 interlocks that are formed on shell 1, so that securely end cap 6 is assembled to the opening end of shell 1.Concentricity between end cap 6 and the shell 1 is guaranteed that by the mode that forms end cap 6 this illustrates below.

The internal diameter of the curved edge 21 of end cap 6 is greater than the external diameter of the opening end of shell 1, and by non-oil suction and non-absorbent material for example the encapsulant 24 made of rubber be placed between the outer peripheral face of curved edge 21 and shell 1 opening end, the two sealing.The bearing 12 of axle 13 the left end of support rotor 5 is assembled in the recess 25 on the outer face that is formed on end cap 6.

Output shaft 13a passes end cap 6 and protruding, and departs from the axis of the axle 13 of rotor 5, and its bias is e.Reference number 26 expression construction bolt holes are formed on the bottom of shell 1 and each the construction bolt hole 26 on the

end cap

6 and 26 and make that the through bolt (not shown) is installed can be passed.Reference number 27 expression is formed on a pair of input in the tube connector 28, tube connector 28 be formed on stand base 7 than low side, link to each other with the external dc power (not shown).

Groove on the outer face of reference number 16 expression end caps 6 is used for holding sealing gasket, and the generation type of sealing gasket will be in following explanation.Be that groove 16 forms Φ shape, surround output shaft 13a and axle 13, and topped construction bolt hole 26 around.Reference number 17 expression location recesses; For example four location recesses 17 are arranged in groove 16.Reference number 18 expression circular arc recesses; For example four circular arc recesses 18 are arranged in the outside of groove 16.Like this, form rib shape ledge 19 near groove 16.

By circular arc recess 18 is provided, on corresponding inner face, form circular arc ledge 18a on the outer face of end cap 6.By with the periphery of ledge 18a and the inner peripheral surface interlock of shell 1 opening end, can keep the concentricity of end cap 6 and shell 1.

Above-mentioned end cap 6 preferably should be formed by the sheet metalwork.Be that end cap 6 is made by the sheet metal in the forming process at the same time, this process comprise with a pair of corresponding to end cap 6 inner face and the form metal mould of the profile of outer face carry out punching press, cutting and boring.

Fig. 6 and 7 is plane graph and the profiles that are used for the sealing gasket of embodiments of the invention.In Fig. 6 and 7, sealing gasket 40 by a kind of flexible, flexible material for example rubber make, its planar profile is a Φ shape, so sealing gasket 40 can be assemblied in the groove 16 shown in Figure 4 and 5.Reference number 26 expression construction bolt holes, reference number 41 expression positioning salient branches.Positioning salient divides 41 positions that are placed on corresponding to the recess shown in the Figure 4 and 5 17, forms the shape corresponding to recess 17.

After shell 1, stand base 7 and end cap 6 are assembled as shown in Figure 5, encapsulant 24 is placed between the opening end outer peripheral face of the curved edge 21 of end cap 6 and shell 1.When the interlock pawl on the curved edge of end cap 6 bent into the outer recess of placing 23 of shell 1 opening end, stand base 7, end cap 6 and shell 1 be interlock mutually closely, has sealed the inner space.

Zu Zhuan electrical micro-machine can be by also using through bolt (not shown) fit sealing pad 40, the external equipment of packing in the groove 16 on the end cap shown in the Figure 4 and 5 that the sealing gasket 40 shown in Fig. 6 and 7 is packed in a manner described.In this case, since when recess 17 interlocks in ledge on the sealing gasket 40 41 and the groove 16 sealing gasket 40 be positioned and temporarily remain on the original place, external equipment so electrical micro-machine can be packed at an easy rate.By electrical micro-machine is installed in a manner described, near the of output shaft 13a, bearing 12 and construction bolt hole 26 can seal by all sealing gaskets 40 airtightly, prevented that water, wet goods from infiltrating the inner space of shell 1.

More than Shuo Ming embodiment provides ledge 41 on sealing gasket 40, and recess 17 interlocks on this ledge 41 and the end cap 6 are not even but what problem cancellation ledge 41 and recess 17 can cause yet.By recess and the temporary transient sealing gasket 40 that keeps in advance on the equipment externally are provided on the equipment externally, just electrical micro-machine can be installed.

In addition, more than the central shaft of output shaft 13a departs from axle 13 the central shaft of motor 5 in Shuo Ming the example, but the present invention certainly is used for output shaft 13a and axle 13 is electrical micro-machines of concentric shafts.Can suitably select to be assembled to the number of the permanent magnet 2 on shell 1 inner peripheral surface according to the required specification of motor, and the number of brush carriage 9 and stand base 7 power up brushes 8.

Permanent magnet 2 can be made hollow cylinder, and side face provides the magnetic pole of predetermined number within it.In addition, also can suitably select the interlock pawl 22 on end cap 6 and the shell 1 and the number of recess 23.Encapsulant 24 can be packed into before end cap is contained in shell 1 on the inner peripheral surface of curved edge 21 of end cap 6 in advance.

The present invention with said structure and operation has reached following effect:

(1) can prevent that sealing, wet goods enter the inner space that holds motor, thereby improve Water proofing property and the grease proofness of micro machine.

(2) can be not the installed surface with the electrical micro-machine of motor mounting to the external equipment not be carried out machining, and be convenient to install electrical micro-machine.

(3) cancelled the waterproof cover that is used for electrical micro-machine before this, this is convenient to electrical micro-machine is installed in the external equipment, has reduced micro-motor to shared space.

(4) can improve the rigidity of end cap by form rib shape ledge near groove, so can reduce to constitute the thickness of the material of end cap.

Claims

1. an electrical micro-machine comprises: the hollow cup-shaped shell of being made, be shaped as the end by metal material, permanent magnet is assemblied on the face on every side of this shell securely, have facing to the armature core of described permanent magnet and the rotor of commutator, and the two all is assemblied in the stand base and the end cap of an opening end of described shell; Be used to support the brush carriage of brush, make described brush contact slidably with described commutator, and the pair of input terminals that is electrically connected with described commutator on the described stand base; Described rotor is by the bearings that provides on described outer casing bottom and the described end cap, the output shaft that it is characterized in that described rotor passes described end cap and protruding, a groove is provided on the outer face of described end cap, its generation type for this groove surround construction bolt hole on described output shaft and the topped described end cap around; The sealing gasket of making by a kind of flexible, the flexible material described groove of packing into.

2. electrical micro-machine as claimed in claim 1 is characterized in that described end cap made by the uniform material of a kind of thickness, and forms rib shape ledge near described groove.

3. electrical micro-machine as claimed in claim 1 is characterized in that described described groove and the described sealing gasket that is arranged on the end cap forms by this way, makes them all have the corresponding annular part.