CN2770204Y - Small size motor - Google Patents

Abstract

The utility model relates to a miniature motor which is provided with a stator (9) and a rotor (10), wherein the stator comprises an inner flange processing part (11) which forms a bearing shield shell in the central part, a bracket (4) which is made of magnetic material and forms an integral structure with a mounting base part (12), an oil-retaining bearing (5), a stator core (8) fixed at the outer side of the inner flange processing part, and a bearing bracket (14) fixed at the inner peripheral side of the stator core; the rotor comprises an output shaft (1) which makes use of the oil-retaining bearing to be supported freely and is fixed on a frame (2) of the central part, and a cylinder-shaped rotor magnet (3) fixed at the inner periphery of the frame; the bearing bracket is provided with a cylinder part (15) which has gaps and is arranged between the outer peripheries of the oil-retaining bearing, and an end face part (13) which extends from one end part of the cylinder part to the side of the internal diameter. In addition, an annular elastomer (18) is arranged between the end face (17) of the inner flange processing part and the other end face (16) of the cylinder part of the bearing bracket.

Description

Miniature motor

Technical field

The utility model, relate generally to as disc drive with and be used for information such as CD-ROM (R/RW) and DVD ± (R/RW) are write down miniature motor with regenerating unit, especially be conceived to the bearing arrangement of miniature motor.

Background technology

In recent years, the disc that information such as CD-ROM (R/RW) and DVD ± (R/RW) is write down and regenerate is being rotated in the miniature motor of driving, according to the requirement of low price cost, do to be used as general bearing arrangement by the formed oiliness bearing of the metal of porous matter.

Fig. 2 is a cutaway view of representing miniature motor structure in the past.Among Fig. 2, the 21st, be rotated the output shaft of transmission, the 22nd, oiliness bearing, the 23rd, the case that oiliness bearing is kept, the 24th, rotor, the 25th, stator, the 26th, the carriage that constitutes by printed base plate.This miniature motor, between rotor 24 and stator 25, utilize the magnetive attraction that takes place successively to obtain revolving force, be fixed on the output shaft 21 of rotor 24 central authorities, utilization is by oiliness bearing 22 and be fixed on the bearing arrangement that the case 23 on the carriage 26 constitutes and be rotated supporting freely, and the rotation that precision is high is transmitted to the outside.

But, along with information such as CD-ROM (R/RW) and DVD ± (R/RW) are write down and regeneration medium with the high speed of equipment, the oily structure of guarantor that exist the equipment of the long-term reliability of bearing arrangement to tail off, must constitute the oiliness bearing of bearing arrangement reaches the important problem such as countermeasure of dispersing for the oil that contains in oiliness bearing.

Promptly, in structure in the past as described above, for the periphery of oiliness bearing 22 is airtight with case 23, the pressure that takes place at the contact site of output shaft 21 and oiliness bearing 22 when utilizing output shaft 21 rotation, and the pressure to the end face of oiliness bearing 22 is increased, oiling at the end face of oiliness bearing 22 is blown, especially the top surface side of rotor 24 attached to its inside top surface on.In addition, since attached to the oil on the rotor 24 because of centrifugal force on the inside top surface of rotor to radially diffusion, do not return in the oiliness bearing 22, so remain on oil minimizing in the oiliness bearing 22, can not play normal lubrication, existence can not be carried out the problem that high-precision rotation is transmitted.

Therefore, applicant's purpose is, provide and reduce oil while realizing reducing cost and blow out and can keep for a long time the bearing arrangement of the miniature motor that the high accuracy rotation transmits and miniature motor with excellence of this device to the oiliness bearing end face, in the flat 9-294350 communique of Japanese Patent Application Laid-Open, disclosed the technical scheme of the miniature motor of following bearing arrangement: in the top surface side of the rotor of the portion that is pressed into of oiliness bearing and case, by that the periphery of oiliness bearing is not airtight part is set the pressure to the end face of oiliness bearing is reduced, energy minimizing oil blows out to the oiliness bearing end face, can keep high-precision rotation transmission for a long time.

Fig. 3 represents the structure of this miniature motor.Among Fig. 3, the 31st, output shaft, the 32nd, oiliness bearing, the 35th, carriage, the 33rd, case, the 34th, rotor.Case 33 and carriage 35 are formed,, make 1/2 to 4/5 size of oiliness bearing 32 total lengths by size with oiliness bearing maintaining part 36 in the top surface side of rotor 34, the periphery of the oiliness bearing 32 of rotor 34 sides is open.According to this structure, can suppress oil and blow out to oiliness bearing 32 end faces, and, by carriage 35 and case 33 are formed as one, have the effect of the constitutional detail number that can reduce miniature motor.

Yet along with the rapid high speed to equipment such as CD-ROM (R/RW) and DVD ± (R/RW), the pressure that radially reaches the bearing face direction of the bearing inside that causes because of the imbalance of disc is bigger, becomes more than the imagination.And at above-mentioned the 2nd in the past in the structure of example, oil is flowed out by the periphery of open oiliness bearing and bearing face from utilizing this pressure, produces the corresponding problem that becomes difficult with long lifetime.

Therefore, the applicant has disclosed the technical scheme of following structure in Japanese Patent Application Laid-Open 2002-262540 communique: in the open part of oiliness bearing periphery, have the gap and columnar cover is installed by end face and the periphery that makes oiliness bearing, even the oil that is extruded from the end face of oiliness bearing disperses rotation, cover also becomes the wall that prevents that oil from dispersing, in addition, the oil that utilizes gap between the cylindrical portion of the periphery of oiliness bearing and cover to make the oiliness bearing that will disperse to cylindrical portion is back to the recovery structure of the oil in the oiliness bearing by this gap.

Fig. 4 represents the above-mentioned the 3rd structure of miniature motor of example in the past.Among Fig. 4, the 41st, output shaft, the 42nd, oiliness bearing, the 43rd, rotor, the 46th, plunging is added the carriage that the mounting base portion 44 of the Ministry of worker 45 and miniature motor forms as one.The plunging that oiliness bearing 42 is fixed on carriage 46 with the state of the part of opening of periphery adds the interior perimembranous of the Ministry of worker 45, and stator core 47 is fixed on the peripheral part that plunging adds the Ministry of worker 45.And, the columnar support of bearing 52 (cover) that is made of the cylindrical portion 50 that has the gap in end face and periphery with oiliness bearing 42 and the end face portion 51 of extending to internal side diameter from a side's of this cylindrical portion end, the end face that adds the Ministry of worker 45 with the plunging of carriage 46 is pressed in the interior perimembranous that is fixed in stator core 47 with the state that the opposing party's of the cylindrical portion 50 of the support of bearing 52 end face docks.

Yet, in above-mentioned structure in the past, be difficult, so can not avoid in the interface of both ends of the surface, producing small gap owing to each end face that will add the Ministry of worker 45 to the plunging of the support of bearing 52 and carriage 46 is finish-machined to desirable plane.Again, the situation that oil flows out from the gap of gap between each iron core of laminate core of above-mentioned interface owing to be fixed in the internal diameter that utilizes the formed stator core 47 of laminate core, might take place because of capillarity in the support of bearing 50.Therefore, exist the oil of oiliness bearing 42 little by little to run off, will keep for a long time the problem that enough reliabilities become difficult from this gap because of the running of miniature motor.

Summary of the invention

Miniature motor of the present utility model has stator and rotor, and described stator is included in plunging that central portion constitutes the bearing case and adds the carriage that magnetic material constituted that the Ministry of worker and mounting base portion work are integral; Oiliness bearing, the part of its total length is fixed on the inboard that plunging adds the Ministry of worker; Be fixed on plunging and add the stator core in the Ministry of worker outside; And the support of bearing that is fixed on all sides in the stator core, described rotor comprises: utilize oiliness bearing and be rotated the output shaft of supporting freely; Output shaft is fixed on framework on the central portion; And the cylindric rotor magnet that is fixed on week in the framework, with following structure as feature:

The support of bearing have and the periphery of oiliness bearing between be provided with the cylindrical portion in gap and the end face portion that extends to internal side diameter from a square end portion of this cylindrical portion, add at plunging between the opposing party's end face of cylindrical portion of the end face of the Ministry of worker and the support of bearing and be equipped with circular elastomer.Adopt this structure, owing to above-mentioned both ends of the surface push elastomer, so can prevent the leakage of oil in the oiliness bearing.Its result adopts the utility model, can provide reliability long-term higher miniature motor.

Description of drawings

Fig. 1 is the cutaway view of the miniature motor structure of expression embodiment of the present utility model.

Fig. 2 is the cutaway view of expression the 1st miniature motor structure in the past.

Fig. 3 is the cutaway view of expression the 2nd miniature motor structure in the past.

Fig. 4 is the cutaway view of expression the 3rd miniature motor structure in the past.

Embodiment

Below, with reference to accompanying drawing embodiment of the present utility model is described.

Among Fig. 1, the 1st, be rotated the output shaft of transmission.The 2nd, framework, in a circumferential direction by the ring-type rotor magnet 3 after multipole magnetized to be pressed into or bonding way was fixed on the interior week of framework 2.And, carry out plunging processing and directly output shaft 1 be pressed at the central portion of framework 2.Like this, rotor 10 is made of output shaft 1, framework 2 and rotor magnet 3.

Carriage 4 is the materials that constitute with magnetic material, and forms by process for stamping, and adds the Ministry of worker 11 at the plunging that substantial middle portion has a prominent shape of ladder.This plunging adds the function that the bearing case that bearing arrangement is accommodated plays in the Ministry of worker 11.And carriage 4 has the plunging that will constitute the bearing case and adds the Ministry of worker 11 and miniature motor and the mounting base portion 12 of usefulness is installed makes the structure that is integral.Like this, owing to plunging being added the structure that the Ministry of worker 11 and mounting base portion 12 works are integral, so form the perpendicularity that plunging adds 11 relative mounting base portions 12 of the Ministry of worker easily accurately.

Add the inboard of the Ministry of worker 11 at the plunging of carriage 4, in order rotating freely output shaft 1 to be supported, and to be pressed into oiliness bearing 5 fixing.

On the other hand, add the outside of the Ministry of worker 11, by the insulator of resin package is had the stator coil assembling body of stator coil 6 to be pressed into and be fixed in the stator core 8 at the plunging of carriage 4.

In addition, the printed base plate 7 of a circuit part that is used to drive and control miniature motor has been installed at least, has been utilized two-sided tape (not shown) and be adhesively fixed in the mounting base portion 12.The winding terminal distribution of stator coil 6 of stator coil being assembled body constitutes stator 9 on printed base plate 7.

In addition, stator 9 is, the support of bearing 14 of drum is pressed into the internal side diameter that is fixed in stator core 8.This support of bearing 14 constitutes to the end face portion 13 that internal side diameter extends by cylindrical portion 15 with from a side's of this cylindrical portion 15 end, cylindrical portion 15 is pressed into the internal side diameter that is fixed in stator core 8.Again, cylindrical portion 15 has and the end face of oiliness bearing 5 and the gap of periphery, and end face portion 13 has the gap at the end face of axial and framework 2.

Above structure is routine in the past identical with the above-mentioned the 3rd.In the present embodiment, add at the plunging of carriage 4 between the opposing party's end face 16 of cylindrical portion 15 of the end face 17 of the Ministry of worker 11 and the support of bearing 14 and be equipped with circular elastomer 18, the structure that pushes this elastomer and described both ends of the surface are docked is and the above-mentioned the 3rd routine in the past difference.

According to said structure, owing to add the elastomer 18 that accompanies between the opposing party's end face 16 of cylindrical portion 15 of the Ministry of worker's 11 end faces 17 and the support of bearing 14 after being compressed at the plunging of carriage 4, so become the closed structure of higher degree.Thus, can prevent to add the oil condition that the Ministry of worker's 11 end faces 17 and the gap of the interface of the opposing party's end face 16 of the cylindrical portion 15 of the support of bearing 14 spill oiliness bearing 5 from the plunging of carriage 4.

This circular elastomer 18 is so-called sealing rings, preferably adopts the silicon rubber of oil synthetic rubber system or acrylonitrile-butadiene rubber etc.

According to this structure, because the support of bearing is provided in the outside that is positioned at oiliness bearing top, thus can increase guarantor's oiliness energy of oiliness bearing, and can will be recycled to from the oil that oiliness bearing disperses the oiliness bearing self.In addition, seal owing to plunging is processed the interface of the opposing party's end face of the cylindrical portion of end surface and the support of bearing with elastomer, so can prevent to make because of capillarity the gap between each iron core the situation of oily outflow from this gap to laminate core.Its result can provide the miniature motor that high speed is corresponding, reliability is high, the life-span is grown with the equipment of CD-ROM (R/RW) and DVD ± (R/RW) wait.

Claims (2)

1, a kind of miniature motor has stator and rotor, and described stator comprises: the plunging that constitutes the bearing case at central portion adds the carriage that the Ministry of worker and mounting base portion make the magnetic material formation that is integral; Oiliness bearing, the part of its total length is fixed on the inboard that described plunging adds the Ministry of worker; Be fixed on described plunging and add the stator core in the Ministry of worker outside; And the support of bearing that is fixed on interior all sides of described stator core, described rotor comprises: utilize described oiliness bearing and be rotated freely the output shaft of supporting; Described output shaft is fixed on the framework on the central portion; And the rotor magnet cylindraceous that is fixed on described framework inboard, it is characterized in that,

The described support of bearing have and the periphery of described oiliness bearing between be provided with the cylindrical portion in gap and the end face portion that extends to internal side diameter from a square end portion of this cylindrical portion, add at described plunging between the opposing party's end face of cylindrical portion of the end face of the Ministry of worker and the described support of bearing and be equipped with circular elastomer.

2, miniature motor as claimed in claim 1 is characterized in that, described elastomer is made of the silicon rubber or the acrylonitrile-butadiene rubber of oil synthetic rubber system.

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