JPH0998548A - Motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the volume, weight and cost of the whole of a bearing holder. by providing the references when integrating respectively the bearing holder in a motor and the motor in a VTR, etc. without increasing the wall thickness of the bearing holder. SOLUTION: In a spindle motor, a shaft 12, a rotor case 6, a driving magnet 11, bearings 24, 25, a bearing holder 5, a stator core 2 and a stator (S) including a stator board 4 are provided. Also, in the bearing holder 5, a cylinder portion 5c for holding the bearings 24, 25 is provided, and on the cylinder portion 5c, a plurality of portions 5j protruded in its radial outside direction are provided. In the respective protruding portions 5J, first and second positioning portions 5k, 5m having respectively circumscribed circles with large and small diameters are provided to be engaged respectively with an inner hole 4a formed in the stator S and with a portion of a chassis 20 for attaching the spindle motor thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor that can be used in various other devices such as a capstan motor of a video tape recorder (hereinafter referred to as "VTR"), and particularly to a bearing holder and its periphery. Regarding the structure.

[0002]

2. Description of the Related Art For example, a conventional motor used as a VTR capstan motor has a structure shown in FIG. In FIG. 5, in the motor, the core holder 3 is placed at the center of the stator core 2 of the core winding set 1,
The core holder 3 is placed on the substrate 4. From above the stator core 2, the bearing holder 5 is inserted into the central through holes 2a, 3a of the stator core 2 and the core holder 3 and the through hole 4a of the substrate 4, and is placed in the recess of the stator core 2. The bearing holder 5 is integrated with the stator core 2 into the board 4 with screws 1
It is fixed at 0. The drive magnet 11 of the rotor case 6 faces the outer periphery of the stator core 2. The bearing is press-fitted and fixed to the bearing holder 5, and the bearing rotatably supports the shaft 12.

The rotor R has a rotor case 6 in which a rotor magnet 11 is mounted and a shaft 12, and the stator S includes a stator core 2 around which a coil 7 is wound, a core holder 3 made of an insulating material, and the substrate 4. Have

The core winding set 1 includes a stator core 2, a coil 7 wound around the stator core 2, an insulating core holder 3 made of resin or ceramic, and a plurality of coils 7 held by the core holder 3 to connect the coils 7. It consists of a terminal 8 of a book. The stator core 2 is made up of the core holder 3
Is fitted and fixed.

As shown in FIGS. 7 to 9, the bearing holder 5 has an inverted T-shaped vertical cross section. However,
In contrast to FIG. 5, the bearing holder 5 is turned upside down in FIGS. 7 to 9. In the bearing holder 5, a screw through hole 5b is formed in the flange portion 5a mounted on the core winding set 1, and a plurality of projecting portions 5d extending outward in the radial direction are formed around the cylindrical portion 5c. A screw hole 5e is formed in the protrusion 5d in parallel with the axis of the bearing holder 5.

As shown in FIG. 6, the substrate 4 is formed with a through hole 4a having a substantially triangular shape in which the cylindrical portion 5c of the bearing holder 5 and a plurality of protruding portions 5d around the cylindrical portion 5c are fitted. A notch 4b into which the positioning pin of the core holder 3 is fitted is formed at a portion corresponding to the apex of the substantially triangular shape of the through hole 4a. The substrate 4 is made of an iron plate whose surface is treated with an insulating film, on which a circuit conductive pattern is formed of copper foil, and a terminal portion 13 is formed at a position corresponding to the terminal 8. The core winding set 1, the bearing holder 5, and the substrate 4 are superposed, and the screw 10 penetrating the stator core 2 and the core holder 3 is screwed into the screw hole 4e of the substrate 4 so that the core winding set 1 and the bearing holder 5 are inserted. The substrate 4 is integrally fixed.

The cylindrical portion 5c of the bearing holder 5 is shown in FIG.
As shown in FIG. 9, it is formed in two stages of a large diameter portion 5g at the base and a small diameter portion 5h at the tip side. The large diameter portion 5g serves as a positioning portion during motor assembly, and when the cylindrical portion 5c of the bearing holder 5 is fitted into the through hole 4a, the large diameter portion 5g.
The bearing holder 5 is positioned with respect to the substrate 4 by fitting it into the through hole 4a using g as a guide and contacting the large-diameter portion 5g with the partially arcuate wall surface of the through hole 4a of the substrate 4. Further, the small diameter portion 5h has a motor
It forms a positioning part for mounting on the chassis 20 such as TR, and when mounting the motor on the chassis 20,
The motor is positioned with respect to the chassis 20 by fitting the small diameter portion 5h into the through hole of the chassis 20 and using the small diameter portion 5h as contact with the wall surface of the through hole of the chassis 20.

[0008]

As described above,
The capstan motor is a standard when the bearing holder 5 is assembled into the capstan motor and the capstan motor is set to V.
The conventional capstan motor requires a reference when incorporating it into a TR, etc., and the large diameter portion 5 formed in the bearing holder 5 is required.
g is a reference when the bearing holder 5 is incorporated in the capstan motor, and the small diameter portion 5h formed in the bearing holder 5 is a reference when the capstan motor is incorporated in a VTR or the like.

As shown in FIG. 9, the large-diameter portion 5g of the bearing holder 5 is formed in a D-shaped cross section and the small-diameter portion 5h is formed in an oval cross-section, but the large-diameter portion 5g is formed. Both the small diameter portion 5h and the small diameter portion 5h are basically formed in a cylindrical shape. However, since the large-diameter portion 5g and the small-diameter portion 5h are used as a reference when the bearing holder 5 is incorporated in the capstan motor and a standard when the capstan motor is incorporated in a VTR or the like, respectively, the large-diameter portion 5g and the small-diameter portion 5h are included. Needs to be provided at a position relatively distant from the central axis of the bearing holder 5, and if the large diameter portion 5g and the small diameter portion 5h are formed in a cylindrical shape, the cylindrical portion 5c of the bearing holder 5 becomes thicker,
The volume of the bearing holder 5 was large. As a result, the material cost of the bearing holder 5 becomes high, and the cost becomes high.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and it is a standard for incorporating the bearing holder into the motor without increasing the thickness of the bearing holder, the VTR of the motor, etc. It is an object of the present invention to provide a motor capable of providing a standard for assembling in a bearing, reducing the volume of the entire bearing holder, reducing the cost, and reducing the weight.

[0011]

To achieve the above object, the invention according to claim 1 includes a shaft, a rotor case, a drive magnet, a bearing, a bearing holder, a stator core and a stator substrate. In a motor including a stator, a bearing holder is provided with a cylindrical portion for holding a bearing and a plurality of protrusions directed outward in the radial direction on the cylindrical portion, and each protrusion has a large circumscribed circle. The first positioning part and the second positioning part having a small circumscribed circle are provided, the first positioning part is engaged with the inner hole formed in the stator, and the second positioning part is engaged with a part of the chassis on which the motor is mounted. It is characterized by A first positioning portion and a second positioning portion are formed on a part of the protruding portion that extends radially outward from the cylindrical portion. The first positioning part and the second positioning part are not formed in a cylindrical shape.

The invention according to claim 2 is characterized in that the protrusions of the bearing holder are evenly arranged at 120 ° intervals around the bearing holder.

According to a third aspect of the present invention, the first positioning portion and the second positioning portion are provided on the protruding portions that communicate with each other in the axial direction.

[0014]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of a motor according to the present invention will be described below with reference to FIGS. It should be noted that the same components as those in the conventional example are designated by the common reference numerals, and the characteristic portions of the present invention will be mainly described.

In FIG. 1, reference numeral S indicates a stator of the capstan motor, and R indicates a rotor of the capstan motor. The rotor R includes a rotor case 6, a shaft 12 press-fitted into a boss formed by burring at the center of the rotor case 6, and a pulley 28 fixed to the rotor case 6 around the shaft 12. To have. The shaft 12 is a bearing 2 made of a sintered oil-impregnated bearing or the like press-fitted into the upper and lower ends of the cylindrical portion 5c of the bearing holder 5.
The bearings 24 and 25 are rotatably supported by the bearings 24 and 25, respectively.

The stator S has a bearing holder 5, a stator substrate 4, a core winding set 1, and a core holder 3.
The core holder 3 is placed at the center of the stator core 2 that constitutes the core winding set 1, and the core holder 3 and the stator substrate 4 are superposed. From below the stator core 2, the bearing holder 5 is inserted into the central through holes of the stator core 2 and the core holder 3 and the inner hole 4 a of the stator substrate 4. Bearing holder 5
Screws 1 to the stator substrate 4 integrally with the stator core 2.
It is fixed at 0. The drive magnet 11 of the rotor case 6 faces the outer periphery of the stator core 2.

As shown in FIGS. 2 to 4, the bearing holder 5 has an inverted T-shaped vertical cross section. In the bearing holder 5, a screw through hole 5b is formed in a flange portion 5a which is superposed on the core winding set 1, and the bearings 24 and 25 are formed.
A plurality of projecting portions 5d directed outward in the radial direction are formed around the cylindrical portion 5c for holding the screw holes 5d.
e is formed parallel to the axis of the bearing holder 5. However, the cylindrical portion 5c is formed with a thin wall thickness and a small outer diameter, and the cylindrical portion 5c and each protruding portion 5d have ribs 5n.
It is connected.

The bearing holder 5 also has a plurality of protrusions 5j extending radially outward on the outer peripheral surface side of the cylindrical portion 5c.
Each protrusion 5j extends in the axial direction of the bearing holder 5,
The first positioning portion 5k is provided on the base portion (lower portion in FIGS. 2 and 3) of each protrusion 5j, and the first positioning portion 5k is provided on the upper portion of each protrusion 5j.
A second positioning portion 5m is formed so as to communicate with the positioning portion 5k. The circumscribing circle 21 (see FIG. 4) of each first positioning portion 5k has a large diameter, and the circumscribing circle 22 of each second positioning portion 5m has a smaller diameter than the circumscribing circle 21 of each first positioning portion 5k. The protrusions 5j forming the first positioning portion 5k and the second positioning portion 5m are evenly arranged at 120 ° intervals around the bearing holder 5, and accordingly, are arranged at three locations. Similarly, the respective protrusions 5d are equally arranged around the bearing holder 5 at 120 ° intervals. Projection parts 5j arranged at three places
One of them is formed with a protrusion 5r for positioning the bearing holder 5 in the circumferential direction with respect to the stator substrate 4 (see FIG. 4). The width of the protrusion 5j is 0.5, for example.
Approximately 5 mm.

The bearing holder 5 can be attached to the stator substrate 4 having the same structure as the stator substrate 4 of the conventional capstan motor described with reference to FIG. The cylindrical portion 5c of the bearing holder 5 is fitted in the inner hole 4a of the stator substrate 4. At this time, the protrusion 5r of the bearing holder 5 is formed in a part of the inner hole 4a of the stator substrate 4 shown in FIG.
The bearing holder 5 is positioned in the circumferential direction by engaging with r. When the cylindrical portion 5c of the bearing holder 5 is fitted into the inner hole 4a of the stator substrate 4, each first positioning portion 5 of the bearing holder 5 is inserted.
k is engaged with the peripheral wall of the inner hole 4a formed in the stator substrate 4 forming a part of the stator S, and the relative positional relationship between the bearing holder 5 and the stator substrate 4 can be set accurately. These stator constituent members are integrally connected by screwing the screw holes 5b of the positioned bearing holder 5, the screws penetrating the stator core 2 and the core holder 3 into the screw holes 4e of the stator substrate 4.

The capstan motor assembled as described above is attached to the chassis 20 of the VTR and other various devices. An inner hole 20 similar to the inner hole 4a formed in the stator substrate 4 is provided in the chassis 20 of various devices.
a is formed (see FIG. 1), and the cylindrical portion 5c of the bearing holder 5 of the capstan motor is fitted into the inner hole 20a. At this time, the second positioning portion 5m of the bearing holder 5 engages with the peripheral wall of the inner hole 20a of the chassis 20, and the relative positional relationship between the bearing holder 5 and the chassis 20, and thus the relative position of the capstan motor and the chassis 20. The positional relationship can be set accurately.

According to the embodiment described above, the inner hole 4 formed in the stator substrate 4 forming a part of the stator.
The first positioning portion 5k that engages with a to set the relative positional relationship between the stator and the bearing holder 5, and the inner hole 20a of the chassis 20 to which the capstan motor is attached to engage with the capstan motor and the chassis 20. Since the second positioning portion 5m for setting the relative positional relationship is provided on the plurality of projecting portions 5j radially outward of the cylindrical portion 5c of the bearing holder 5, the cylindrical portion 5c of the bearing holder 5 excludes the projecting portion 5j. The thickness of the bearing holder 5 can be reduced and the volume of the bearing holder 5 can be reduced. As a result, the material cost of the bearing holder 5 is reduced, and the cost can be reduced. By the way, compared to the conventional bearing holder, the weight is about 3
The weight can be reduced by 0%, and the volume is reduced to about 2/3.

In the embodiment described above, the first
Since the protrusions 5j that form the positioning portion 5k and the second positioning portion 5m are evenly arranged at 120 ° intervals around the bearing holder 5, the relative positional relationship between the stator and the bearing holder 5, the capstan motor, and the chassis 20 are different. It is possible to minimize the number of the protruding portions 5j while accurately setting the relative positional relationship of the above, and thus it is possible to effectively reduce the volume and weight of the bearing holder 5. Furthermore, since the first positioning portion 5k and the second positioning portion 5m are formed on the three protruding portions 5j, the accuracy of the diameter and height of the circumscribed circle of the first positioning portion 5k and the second positioning portion 5m can be set at three locations. There is also an advantage that accuracy is easy to obtain, as long as it is limited and concentrated.

Further, in the above embodiment, the first positioning portion 5k and the second positioning portion 5m are concentratedly provided on the projecting portion 5j which communicates with each other in the axial direction, so that the volume of the bearing holder can be reduced most efficiently. can do.

As the material of the bearing holder 5, for example, zinc or resin can be used. In the case of zinc, die casting can be used, and in the case of resin, molding can be performed. Further, it can be made by using other materials and construction methods, for example, by processing a metal plate into a metal plate. Protrusion 5j forming first positioning part 5k and second positioning part 5m
Need not be provided in three places, and may be provided in more places.

First positioning portion 5k and second positioning portion 5m
May be formed on separate protrusions. For example, a member indicated by a dotted line with reference numeral 5p in FIGS. 2 and 4 shows another example of the second positioning portion which replaces the second positioning portion 5m, and the second positioning portion 5p.
Are integrally formed following the upper ends of the ribs 5n that connect the cylindrical portion 5c and the protruding portions 5d described above. Rib 5n
Are formed in three places at equal intervals, so that the second positioning portions 5p are also formed in three places at equal intervals. The 1st positioning part 5k is formed in the protrusion part 5j like the above-mentioned example. The rib 5n, which is a protrusion separate from the protrusion 5j
Since the second positioning portion 5p is formed on the
It is not necessary to form the second positioning portion 5m on j, but it is possible to form the second positioning portion 5m and then further form the second positioning portion 5p. In this case, the second
The positioning portions 5m and 5p are formed on the same circumscribing circle.

It goes without saying that the motor according to the present invention is not limited to the capstan motor for VTR as in the above-mentioned embodiment, but can be applied to motors for other purposes. Further, in the above-described embodiment, the peripheral facing type with the core has been described as an example, but the surface facing type may also be used.
A coreless type may be used, and the type of the motor is not limited.

[0027]

According to the first aspect of the present invention, the first positioning portion that engages with the inner hole formed in the stator to set the relative positional relationship between the stator and the bearing holder, and the chassis to which the motor is attached. Since the second positioning portion that engages with a part of the bearing to set the relative positional relationship between the motor and the chassis is provided on the plurality of protruding portions formed on the cylindrical portion of the bearing holder toward the radially outer side, The thickness of the cylindrical portion can be reduced except for the protruding portion, and the volume of the bearing holder can be reduced. As a result, the material cost of the bearing holder is reduced, and the cost can be reduced.

According to the second aspect of the present invention, the protrusions forming the first positioning portion and the second positioning portion are evenly arranged at 120 ° intervals around the bearing holder, so that the stator and the bearing holder are opposed to each other. While accurately setting the positional relationship and the relative positional relationship between the motor and the chassis, the number of protrusions can be minimized, and thus the volume and weight of the bearing holder can be effectively reduced. Further, since the first positioning part and the second positioning part are formed on the three protruding parts, the accuracy of the diameter and height of the circumscribed circle of the first positioning part and the second positioning part is limited to three parts, and concentrated. There is also an advantage that accuracy can be easily obtained.

According to the third aspect of the present invention, since the first positioning portion and the second positioning portion are concentratedly provided on the protruding portions that communicate with each other in the axial direction, the volume of the bearing holder can be reduced most efficiently. can do.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a half body of an embodiment of a motor according to the present invention.

FIG. 2 is a vertical sectional view of a bearing holder used in the same motor.

FIG. 3 is a front view of the above bearing holder.

FIG. 4 is a plan view of the above bearing holder.

FIG. 5 is a vertical sectional view showing an example of a conventional motor.

FIG. 6 is a plan view of a motor board used in the motor of the above.

FIG. 7 is a vertical cross-sectional view of a bearing holder used in the same motor.

FIG. 8 is a front view of the above bearing holder.

FIG. 9 is a plan view of the above bearing holder.

[Explanation of symbols]

 2 stator core 4 stator substrate 4a inner hole 5 bearing holder 5c cylindrical part 5j protruding part 5k first positioning part 5m second positioning part 6 rotor case 7 coil 11 drive magnet 12 shaft 20 chassis 21 circumscribing circle 22 circumscribing circle 24 bearing 25 bearing S Stator R rotor

Claims (3)

[Claims] 1. A shaft, a rotor case that rotates integrally with the shaft, a drive magnet mounted on the rotor case, a bearing that rotatably supports the shaft, and a bearing holder that holds the bearing. In a motor including a stator core having a salient pole around which a coil is wound, the salient pole facing the drive magnet, and a stator including a stator substrate on which a conductive pattern for energizing the coil is formed. The bearing holder has a cylindrical portion for holding the bearing and a plurality of radially outwardly projecting portions on the cylindrical portion, and each of the projecting portions has a circumscribing circle having a large diameter and a circumscribing circle. A second positioning part having a small diameter is formed, the first positioning part engages with the inner hole formed in the stator, and the second positioning part is a part of the chassis to which the motor is attached. Motor, characterized in that the engagement. 2. The motor according to claim 1, wherein the protrusions of the bearing holder are evenly arranged at 120 ° intervals around the bearing holder. 3. The motor according to claim 1, wherein the first positioning portion and the second positioning portion are respectively provided on projecting portions that communicate with each other in the axial direction.