JP5226499B2 - Disc rotation motor - Google Patents

Description

  The present invention mainly relates to a disk drive device for recording music and video information on an optical medium such as a CD and a DVD, and reproducing the recorded information, and more particularly to the structure of a brushless motor for rotating a disk. is there.

In recent years, disk drive devices that record music and video information on optical media such as CDs and DVDs and reproduce the recorded information have been demanded to be small and thin. Accordingly, in order to secure the bearing length, a structure has been proposed in which a concave portion is provided in the center of the rotor portion, the bearing portion is accommodated therein, and a mechanism for preventing the rotor portion from coming off is configured. (For example, see Patent Document 1)
FIG. 7 shows a cross-sectional view of a conventional disk rotation motor disclosed in Patent Document 1 described above.

  In FIG. 7, the disk rotation motor is composed of a rotor portion 101 and a stator portion 102, and an engagement portion 104 is formed by cutting or the like at the inner opening of the turntable portion 103 of the rotor portion 101. A rotor removal prevention mechanism is configured by engaging in the axial direction with an engaged portion 107 formed on the fixed retaining member 106.

In addition to the above prior art, a structure that constitutes a rotor removal prevention mechanism using a yoke of a magnet that attracts the rotor portion has also been proposed. (For example, see Patent Document 2)
FIG. 8 shows a cross-sectional view of a conventional disk rotating motor disclosed in Patent Document 2.

  In FIG. 8, the disk rotation motor is composed of a rotor portion 108 and a stator portion 109. A retaining member 111 is fixed to the turntable portion 110 of the rotor portion 108 by welding, and this retaining member 111 is axially engaged with the outer periphery of the yoke 114 of the rotor portion attracting magnet 113 fixed to the bearing holder 112. By combining them, a rotor removal prevention mechanism is configured.

Further, the demand for cost reduction of the disk drive device has become very strict. However, a structure in which the engaging portion is integrally formed with the turntable portion of the rotor portion by press working has been proposed. (For example, see Patent Document 3)
FIG. 9 shows a cross-sectional view of a conventional disk rotating motor disclosed in Patent Document 3.

In FIG. 9, the disk rotation motor includes a rotor part 115 and a stator part 116. The turntable portion 117 of the rotor portion 115 is integrally formed with an engagement portion 118 for preventing the rotor from coming off. A spiral structure 120 is formed in a metal housing 119 that is a bearing holder of the stator portion 116. When the rotor part 115 is assembled to the stator part 116, the turntable part 117 is rotated and the engaging part 118 is inserted into the helical structure 120 while being screwed. After the engagement portion 118 passes from the spiral structure 120, a rotor removal prevention mechanism is formed in which the engagement portion 118 and the spiral structure 120 are engaged in the axial direction. Then, by rotating the turntable portion 117 in the direction opposite to that during insertion while screwing the engaging portion 118 into the helical structure 120, the rotor portion 115 is passed through the engaging portion 118 from the helical structure 120 and the stator portion 116. Can be removed from. Thereby, a rotor removal prevention mechanism in which the rotor portion 115 can be easily inserted into and removed from the stator portion 116 can be configured.

In order to further simplify the structure of the disk drive motor, a structure in which the engaging portion 118 of the turntable 117 is bent by plastic deformation and engaged with the engaged portion of the metal housing 119 has been proposed. (For example, see Patent Document 4)
JP 2002-176742 A JP 2005-354757 A JP 2006-325333 A JP 2008-123575 A

  In recent years, disk rotation motors used in disk drive devices have been required to be small, thin, and low in cost, and have a long life performance of several thousand hours, and reliability against repeated insertion and removal of disks of several tens of thousands of times. Is also required.

  The drop prevention mechanism shown in FIG. 7 has an advantage that it is easy to reduce the size and thickness by forming a bearing and a drop prevention structure in the recess in the center of the rotor portion. However, since the retaining member 106 made of an elastic member in which the engaged portion 107 is formed is fixed to the bearing holder 105 by press-fitting or bonding, the durability against repeated detachment of the disk several tens of thousands of times. It is not preferable when thinking. Moreover, it is necessary to set the material and shape which can be elastically deformed, and the material cost is higher than that of a general steel plate.

  In the drop prevention mechanism shown in FIG. 8, the stopper member 111 is fixed to the turntable portion 110 by welding. When the engagement portion of the prevention mechanism is elastically deformed and engaged, a moment is generated in a direction in which the retaining member 111 is peeled off from the turntable portion 110. Therefore, as in the case of the removal prevention mechanism shown in FIG. Considering durability against repeated disk insertion / removal of 10,000 times, it is not preferable.

  Further, like the retaining structure shown in FIG. 7, it is necessary to set a material and a shape that can be elastically deformed, and the material cost is higher than that of a general steel plate.

  On the other hand, the retaining mechanism shown in FIG. 9 is formed integrally with the turntable portion 117 by the press-engagement engaging portion 118 and the metal housing 119 by the press working. In addition to being advantageous, since it is integrated, it has high rigidity and excellent durability. However, since the retaining structure is configured lower in the axial direction than the turntable portion 117, and the engaging portion must be configured with the same plate thickness as the turntable portion, etc. This is disadvantageous in terms of the configuration of fastening the core and securing the bearing length.

In order to solve the above problems, the present invention provides a rotor frame integrally formed with a turntable portion on which a disk is mounted, a disk alignment member for centering and supporting the disk, a rotor magnet attached to the rotor frame, and the rotor A rotor portion having a shaft fixed at the center of the frame; a bearing for supporting the shaft; a metal housing for holding the bearing; a core disposed opposite to the rotor magnet and provided with winding; and the metal housing In a disk rotation motor comprising a stator portion having a bracket for holding a bracket, at least one through-hole is formed in the top surface of the rotor frame, and a retaining member having at least one engagement portion is formed in the through-hole. Attached to the hole by inserting the engaging portion, and the axial direction of the metal housing An engaged portion is integrally formed on the side end surface toward the radially outer side, and a diameter dimension of a circle inscribed in the engaging portion of the retaining member is larger than an outer dimension of the engaged portion of the metal housing. Set to be small, and further, a notch portion having a width through which the engaging portion can be inserted is formed in the engaged portion of the metal housing in a state in which the center is deviated from the center line of the metal housing, When the rotor part is inserted into the stator part, the engaging part of the retaining member is passed in accordance with the position of the notch part of the metal housing, and after the insertion is completed, the engaged part of the metal housing And at least a part of the engaging portion of the retaining member moves to a position where they overlap each other when viewed in the axial direction to constitute a mechanism for preventing the rotor portion from being detached from the stator portion.

  According to the present invention, since the metal housing having the retaining member and the engaged portion can be formed by press working, it is advantageous in terms of cost, and also has high rigidity and excellent durability. Yes. In addition to the fact that a retaining structure can be configured in the concave shape in the center of the rotor frame, it is advantageous for thinning, and the notched portion of the engaged portion is formed with a bias with respect to the center line. Since it is a retaining structure that is assembled by moving the portion in the biasing direction or the opposite direction, there is no stress applied to the member during assembly, and a highly reliable motor can be configured.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
1 is a structural sectional view of a disk rotation motor according to Embodiment 1 of the present invention, FIG. 2A is an upper perspective view of a rotor portion of the disk rotation motor according to Embodiment 1 of the present invention, and FIG. (B) is a lower perspective view, FIG. 3 (a) is an upper perspective view of the disk alignment member according to Embodiment 1 of the present invention, FIG. 3 (b) is a lower perspective view, and FIG. 5 is a perspective view of a retaining member according to Embodiment 1, and FIG. 5 is an upper perspective view of a stator portion of a disk rotation motor according to Embodiment 1 of the present invention. 6 (a) to 6 (g) are schematic views of a retaining engagement process according to Embodiment 1 of the present invention.

  In FIG. 1, the disk rotation motor includes a rotor frame 2 integrally formed with a turntable portion 1 on which a disk is mounted, a disk alignment member 3 for centering and supporting the disk, and a rotor magnet attached to the rotor frame 2. 4, a rotor portion 8 having a shaft 5 fixed at the center of the rotor frame 2 and a retaining member 7 formed with an engaging portion 6, a bearing 9 for supporting the shaft 5, and the bearing 9 are held. It is comprised by the stator part 14 provided with the metal housing 10, the core 12 arrange | positioned facing the rotor magnet 4, and the winding 11 was given, and the bracket 13 holding the metal housing 10. FIG.

  As shown in FIG. 1, the rotor portion 8 has a recess 15 formed at the center of the inner opening of the rotor frame 2. And as shown in FIG. 1, the metal housing 10 which hold | maintains the bearing 9 and the bearing 9 is accommodated in the recessed part 15. As shown in FIG. Further, as shown in FIG. 2B, the engaging portion 6 of the retaining member 7 is inserted into the recess 15 through a through hole 16 formed in the top surface of the rotor frame 2. As shown in FIG. 4, the retaining member 7 includes a substantially ring-shaped annular portion 7 a, and an engaging portion 6 that protrudes in two axial directions so as to face the circumference of the annular portion 7 a. It is formed by. The front end 6a of the engaging portion 6 is folded back in the radial direction in a key shape, and is formed in a J shape as a whole. As shown in FIGS. 1 and 2A, the disc alignment member 3 is fixed to the rotor frame 2 with the retaining member 7 interposed therebetween. The disk aligning member 3 is formed by resin molding, and includes a fixing support column 17 that protrudes inward from the top surface as shown in FIGS. 1 and 3B. The fixing member 17 determines the position of the retaining member 7 in the radial direction. Further, as shown in FIGS. 3A and 3B, the disk aligning member 3 is formed with a pressing spring portion 18 having elasticity in the axial direction on the top surface portion, and the retaining member 7 is retained by the pressing spring portion 18. Is fixed to the rotor frame 2 by pressure contact in the axial direction.

  Further, as shown in FIGS. 5 and 6A, the engaged portion is formed with notches 19 as many as the engaging portions 6 of the retaining member 7 on the upper end surface in the axial direction of the metal housing 10 of the stator portion 14. The joint portion 20 is integrally formed outward in the radial direction.

  The diameter dimension of the circle inscribed in the engaging part 6 of the retaining member 7 is set smaller than the outer dimension of the engaged part 20 of the metal housing 10.

  Further, the width of the cutout portion 19 of the metal housing 10 indicated by the symbol w in FIG. 6B is formed to be a size that allows the engagement portion 6 of the retaining member 7 to be inserted. Further, as shown in FIG. 6B, the notch 19 is formed so that the center C <b> 2 is deviated from the center line C <b> 1 of the metal housing 10.

  As shown in FIGS. 6C and 6D, when the rotor portion 8 is inserted into the stator portion 14, the engagement portion 6 of the retaining member 7 is inserted into the through hole 16 of the rotor frame 2. Then, the notch 19 of the metal housing 10 is moved in the biasing direction so that the engaging part 6 fits in the notch 19.

  Thereafter, as shown in FIG. 6 (e), the engaging portion 6 of the retaining member 7 is lowered axially downward (in the direction of the arrow) while passing through the notch 19 of the metal housing 10, and the rotor portion 8 is moved to the stator. Incorporated into part 14. From this state, as shown in FIGS. 6 (f) and 6 (g), in the state where the engaging portion 6 of the retaining member 7 is inserted into the through hole 16 of the rotor frame 2, the displacement of the notch portion 19 of the metal housing 10. In the direction opposite to the direction, at least part of the engaging part 6 is moved out of the range of the notch part 19 and moved to a position where at least part of the engaged part 20 of the metal housing 10 overlaps with the engaged part 20 when viewed from the axial direction. Complete.

  Here, the through hole 16 of the rotor frame 2 allows the engagement portion 6 of the retaining member 7 to pass through in accordance with the position of the notch portion 19 of the metal housing 10, and after the passage is completed, the engaged portion of the metal housing 10. The engagement portion 6 of the retaining member 7 is formed in a size that can move to a position where at least a part thereof overlaps when viewed in the axial direction.

  Thereafter, the disk alignment member 3 is inserted and fixed to the rotor frame 2. At this time, the fixing support 17 formed on the disk alignment member 3 is brought into contact with the side surface of the retaining member 7 to prevent the engaging portion 6 of the retaining member 7 from moving again. In order to prevent rattling of the retaining member 7 due to vibration or the like, the pressing spring portion 18 is pressed against and fixed to the rotor frame 2 in the axial direction.

  In the above state, when the rotor part 8 is moved upward in the axial direction, the engaging part 6 of the retaining member 7 and the engaged part 20 of the metal housing 10 are engaged to restrict the movement of the rotor part 8. Therefore, it functions as a drop prevention mechanism. In the present embodiment, the engaging portion 6 is formed on the circumference of the annular portion 7a of the retaining member 7 symmetrically with respect to the center of the annular portion 7a, and the center of the notch portion 19 is formed in the metal housing. Since it is formed to be deviated with respect to the center line of 10, even if one of the engaging portions 6 is within the range of the notch portion 19, the other engaging portion 6 is always in the notch portion 19. Since the configuration is such that at least a part thereof overlaps with the engaged portion 20 when viewed from the axial direction outside the range, the rotor portion 8 cannot be easily removed.

  In the present embodiment, two engaging portions 6 of the retaining member 7 are formed and the same number of through-holes 16 of the rotor frame 2 are formed. However, the engaging portion 6 has one, or two or more engaging portions 6. Even if there are a plurality of them, it is possible to satisfy the same function, and there is no problem even if the number of the through holes 16 of the rotor frame 2 is larger than the engaging portion 6 of the retaining member 7.

  Further, in the present embodiment, the center of the notched portion 19 of the engaged portion 20 is biased in parallel to the center line of the metal housing 10, and the engaging portion of the retaining member 7 in the biasing direction. 6 is moved in the axial direction below the notch 19, and after the engagement is completed, the engagement 6 is moved in the direction opposite to the biasing direction. Although the stop mechanism is configured, it is not always necessary to form the center of the notch 19 so as to be parallel to the center line of the metal housing 10, and an arbitrary direction can be set as the direction of the bias. Further, the notch portion 19 of the engaged portion 20 of the metal housing 10 and the engaging portion 6 of the retaining member 7 are formed so as to face each other at two places, but it is not always necessary to face each other. As long as the notch 19 and the engaging part 6 are set in a corresponding positional relationship, they may be formed at an arbitrary position.

  Further, in the present embodiment, the stopper is configured in the concave portion 15 formed in the central portion of the inner opening of the rotor frame 2, but the center of the metal housing 10 such as the lower side of the turntable portion 1. Arrangement is made as long as a retaining structure that is formed by biasing the notched portion 19 of the engaged portion 20 with respect to the wire and moving the engaging portion 6 of the retaining member 7 in the biasing direction or the opposite direction can be arranged. Is possible.

  The shape of the tip 6a of the engaging portion 6 of the retaining member 7 is preferably formed in a J shape by folding back into a key shape radially inward in consideration of the load direction applied to the retaining member 7 and the like. As a result, the retaining member 7 receives predominantly tensile stress, not bending stress, and the resistance to deformation due to excessive stress is enhanced.

  In the present invention, the material of the retaining member 7 can be arbitrarily selected, and can be formed not only by pressing a metal thin plate, but also by molding a metal spring material, a resin molded member, etc. Can be substituted.

  It is useful for brushless motors for mobile devices that require high reliability and low cost in addition to miniaturization and thinning, such as optical media spindle motors.

Sectional view of the structure of the disk rotation motor according to the first embodiment of the present invention. (A) Upper perspective view of the rotor part of the disk rotation motor according to the first embodiment of the present invention, (b) Lower perspective view (A) Upper perspective view of disk alignment member according to Embodiment 1 of the present invention, (b) Lower perspective view 1 is a perspective view of a retaining member according to Embodiment 1 of the present invention. The stator part upper side perspective view of the disk rotation motor which concerns on Embodiment 1 of this invention (A), (c), (e), (f) Perspective perspective view showing an outline of a retaining engagement process according to Embodiment 1 of the present invention, (b), (d), (g) Fig. 3 is a cross-sectional view of a principal part showing an outline of a retaining engagement process according to the first embodiment of the invention. Structural sectional view showing a conventional disk rotation motor (1) Structural sectional view showing a conventional disk rotating motor (2) Structural sectional view showing a conventional disk rotation motor (3)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 103, 110, 117 Turntable part 2 Rotor frame 3 Disc alignment member 4 Rotor magnet 5 Shaft 6, 104, 118 Engagement part 6a Tip 7, 106, 111 Retaining member 7a Ring part 8, 101, 108 , 115 Rotor portion 9 Bearing 10, 119 Metal housing 11 Winding 12 Core 13 Bracket 14, 102, 109, 116 Stator portion 15 Recess 16 Through hole 17 Fixing strut portion 18 Pressing spring portion 19 Notch portion 20, 107 Engaged Part 105, 112 Bearing holder 113 Suction magnet 114 York 120 Spiral structure C1, C2 Center w Notch width

Claims (6)

A rotor frame integrally formed with a turntable portion for mounting a disk, a disk alignment member for centering and supporting the disk, a rotor magnet attached to the rotor frame, and a shaft fixed to the center of the rotor frame A rotor portion, a bearing that supports the shaft, a metal housing that holds the bearing, a core that is disposed opposite to the rotor magnet and that is wound, and a stator portion that includes a bracket that holds the metal housing. In the disk rotating motor, at least one through hole is formed on the top surface of the rotor frame, and a retaining member having at least one engaging portion is inserted and attached to the through hole. On the upper end surface in the axial direction of the metal housing. An engagement portion is integrally formed, a diameter dimension of a circle inscribed in the engagement portion of the retaining member is set to be smaller than an outer dimension of the engagement portion of the metal housing, and the engagement of the metal housing is further reduced. In the joint portion, a notch portion having a width through which the engaging portion can be inserted is formed in a state where the center is deviated with respect to the center line of the metal housing, and the rotor portion is inserted into the stator portion. Passes through the engaging portion of the retaining member in accordance with the position of the notch portion of the metal housing, and after the insertion is completed, at least one of the engaged portion of the metal housing and the engaging portion of the retaining member. A disk rotating motor that constitutes a mechanism for preventing the rotor portion from coming off from the stator portion by moving to a position where the portion overlaps when viewed from the axial direction. 2. The disk rotation motor according to claim 1, wherein a concave portion for housing the bearing is formed in the center of the inner opening of the rotor frame, and the engaged portion and the engaging portion are accommodated in the concave portion. 3. The disk rotation motor according to claim 1, wherein the front end of the engaging portion is formed in a J shape by being folded back radially inward. 4. The retaining member is sandwiched between the disk aligning member and the rotor frame, protrudes inward from the top surface of the disk aligning member to form a fixing column, and the engaging portion of the retaining member is a notch in the metal housing. After the insertion is completed, the fixing support column is prevented from being detached while at least a part of the engaged portion of the metal housing and the engaging portion of the retaining member are overlapped when viewed from the axial direction. The disk rotating motor according to any one of claims 1 to 3, wherein the disk rotating motor is in contact with a side surface of the member. The retaining member is sandwiched between the disk aligning member and the rotor frame, and a pressing spring portion having elasticity in the axial direction is formed on the top surface of the disk aligning member, and the retaining member is attached to the rotor frame by the pressing spring portion. The disk rotation motor according to any one of claims 1 to 4, wherein the disk rotation motor is fixed by pressure contact in an axial direction. 6. A disk drive device on which the disk rotation motor according to claim 1 is mounted.

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