KR20070113570A - Stepping motor - Google Patents

Abstract

A stepping motor is provided to prevent deterioration of an elastic member by installing the elastic member between a cover plate or an end cover and a thrust holder. A stepping motor includes a bracket(110), a lead screw(160), a rotor(167), a housing(120), a stator(170), a cover plate(140), a thrust holder(150), a pivot bearing(130), and an elastic member(180). The bracket includes a rest plate(111), a first side plate(113), and a second plate(115). The first and second plates are formed on both ends of the rest plate. The lead screw is installed through the first side plate and rotates reversibly. The rotor is fixed on an outer circumference of an end of the lead screw. The housing is coupled on the first side plate embracing the rotor. The stator is coupled inside the housing embracing the rotor and rotates the rotor. The cover plate is coupled to the housing and is concentric with the housing. The thrust holder is coupled to the cover plate and the stator movably lengthwise of the lead screw, is concentric with the cover plate, supports an end of the lead screw. The pivot bearing is coupled to the second side plate, is concentric with the thrust holder, and supports an other end of the lead screw. The elastic member is formed between the cover plate and the thrust holder, and supports the thrust holder.

Description

Stepping Motor {STEPPING MOTOR}

1A and 1B are cross-sectional views showing the configuration of a conventional stepping motor.

Figure 2 is a cross-sectional view showing the configuration of a stepping motor according to an embodiment of the present invention.

3 is an exploded perspective view of the main portion of FIG. 2;

* Explanation of symbols for main parts of the drawings

110: bracket 120: housing

130: pivot bearing 137: ball

140: cover plate 150: thrust holder

160: lead screw 167: rotor

170: stator 180: elastic member

The present invention relates to a stepping motor.

1A and 1B are cross-sectional views showing the configuration of a conventional stepping motor, which will be described.

As shown in FIG. 1A, a bracket 11 having a supporting plate 11a and first and second side plates 11b and 11c is provided. One surface of the housing 13 is coupled to the first side plate 11a, and the thrust holder 15 and the cover plate 17 are coupled to the other surface of the housing 13.

The bobbin 21 is installed inside the housing 13, and the coil 23 and the tooth yoke 25 are respectively provided on the outer circumferential surface and the inner circumferential surface of the bobbin 21.

In addition, one end and the other end of the lead screw 40 are rotatably installed on the pivot bearing 30 coupled to the thrust holder 15 and the second side plate 11c of the bracket 11, and the housing is rotatably installed. (13) The magnet 45 is fixed to the outer circumferential surface of the lead screw 40 therein. The lead screw 40 rotates forward and backward by the action of the magnet 45 and the coil 23, and the optical pickup (not shown) installed on the lead screw 40 is linearly reciprocated by the forward and reverse rotation of the lead screw 40. To exercise. Reference numeral 31 is a washer spring.

In the conventional stepping motor as described above, since one end and the other end of the lead screw 40 are directly in contact with the fixed thrust holder 15 and the pivot bearing 30, the lead screw 40 and the thrust holder 15 The friction force between the lead screw 40 and the pivot bearing 30 is large. Due to this, there is a disadvantage that a lot of noise occurs and the characteristics are degraded.

In order to reduce the frictional force at both ends of the lead screw 40, an expensive material having properties such as high lubrication, wear resistance, and heat resistance should be used.

In order to solve the above disadvantages, as shown in Figure 1b, between the one end of the lead screw 65 and the thrust holder 61, the other end of the lead screw 65 and the pivot bearing 63 A stepping motor with 67 was developed.

However, in the conventional stepping motor as described above, since the thrust holder 61 is installed inside the housing 71, it is difficult to couple the thrust holder 61 to a predetermined position, and the thrust holder 61 is coupled to the predetermined position. It's hard to see if it's done. As a result, since the lead screw 65 is also installed in a twisted state, there is a disadvantage that the reliability of the product is lowered.

In addition, since the arm portion 69a of the cover plate 69, which functions as an elastic member that elastically supports the thrust holder 61, is exposed to the outside, the arm portion 69a of the cover plate 69 may be deformed. .

The present invention has been made to solve the above problems of the prior art, an object of the present invention to provide a stepping motor that can improve the reliability of the product.

Another object of the present invention to provide a stepping motor that can prevent the deformation of the elastic member for supporting the thrust holder.

Stepping motor according to the present invention for achieving the above object, the support plate, the bracket having a first and second side plates formed on both ends of the support plate; A lead screw installed to rotate forward and backward through the first side plate; A rotor fixed to an outer circumferential surface of one end of the lead screw; A housing coupled to the first side plate to surround the rotor; A stator coupled to the inside of the housing in a form of enclosing the rotor and acting on the rotor to rotate the rotor; A cover plate coupled to the housing and concentric with the housing; A thrust holder coupled to the cover plate and the stator to be movable in the longitudinal direction of the lead screw, concentric with the cover plate, and having one end side of the lead screw supported; A pivot bearing coupled to the second side plate to be concentric with the thrust holder and to which the other end side of the lead screw is supported: an elastic member provided between the cover plate and the thrust holder to elastically support the thrust holder.

Hereinafter, a stepping motor according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view showing the configuration of a stepping motor according to an embodiment of the present invention.

As shown, the stepping motor according to the present embodiment has a bracket 110, the bracket 110 has a base plate 111, the first and second side plates 113, 115 formed at both ends of the base plate 111. .

A cylindrical housing 120 having both sides open to the first side plate 113 is coupled, and a pivot bearing 130 is coupled to the second side plate 115. On the inner circumferential surface of one side of the housing 120 coupled to the first side plate 113, a plurality of teeth 121 (see FIG. 3) are bent inwardly at equal intervals, and the cover plate 140 and the thrust holder ( Thrust Holder 150 is coupled. The tooth 121 is inserted into the second bobbin 176, which will be described later, and is coupled to engage with the second tooth yoke 178 and the tooth.

In this case, the housing 120, the pivot bearing 130, the cover plate 140, and the thrust holder 150 are concentric, and the thrust holder 150 is bracketed between the cover plate 140 and the thrust holder 150. An elastic member 180 that is elastically supported toward the 110 is provided. This will be described later.

One end and the other end of the lead screw 160 are respectively supported at the centers of the thrust holder 150 and the pivot bearing 130 so as to be capable of forward and reverse rotation. That is, the lead screw 160 is installed through the first side plate 113, the thrust holder 150 and the pivot bearing 130 in contact with one end and the other end of the lead screw 160, respectively, the lead screw ( The ball 137 is supported to support the 160 to rotate smoothly. The lead screw 160 is provided with an optical pickup device (not shown) that linearly reciprocates along the lead screw 160 as the lead screw 160 rotates forward / reversely.

The rotor 167 having the first and second magnets 167a and 167b is fixed to a portion of the lead screw 160 located outside the first side plate 113, that is, inside the housing 120. The stator 170 is installed to surround the rotor 167 on the outside of the electron 167.

The stator 170 is concentric with the housing 120 and has first and second stators 171 and 175. The first and second stators 171 and 175 are installed to surround the first and second magnets 167a and 167b, respectively, so that the first and second bobbins 172 and 176 concentric with the housing 120, and the first and second First and second tooth yokes coupled to the first and second coils 173 and 177 and the first and second bobbins 172 and 176 wound on the outer circumferential surfaces of the second bobbins 172 and 176 and concentric with the housing 120. (174,178).

The first and second tooth yokes 174 and 178 are formed in a ring-shaped body 174a (see FIG. 3) and a plurality of teeth 174b (see FIG. 3) formed at equal intervals on the inner circumferential surface of the body 174a, respectively. ) The body 174a of the first and second tooth yokes 174,178 is in contact with the sides of the first and second bobbins 172,176, respectively, and the tooth 174b of the first and second tooth yokes 174,178 is first And the inner circumferential surfaces of the second bobbins 172 and 176. At this time, the first tooth yoke 174 is provided in a pair and coupled to one side and the other side of the first bobbin 172, the tooth 174b inserted into the inner circumferential surface of the first bobbin 172 is engaged with each other. Is placed. The second tooth yoke 178 is provided as one, and the tooth of the second tooth yoke 178 is disposed in engagement with the tooth 121 of the housing 120.

The pivot bearing 130 is fixed to the second side plate 115 of the bracket 110, and the cover plate 140 is coupled to the housing 120. In addition, the thrust holder 150 is coupled to the cover plate 140 so as to be able to flow in the longitudinal direction of the lead screw 160, and thus is not separated outward.

The elastic member 180 provided between the cover plate 140 and the thrust holder 150 elastically supports the thrust holder 150 to the bracket 110 side so that the lead screw 160 flows in the length direction of the load side and the half load side. Allow End-Play. At this time, the center of the pivot bearing 130 and the center of the thrust holder 150 should be positioned coaxially so that the lead screw 160 is installed horizontally, thereby the optical pickup installed in the lead screw 160 accurately Can play / record.

Due to the structure of the stepping motor, since the pivot bearing 130 is fixed to the second side plate 115 of the bracket 110 exposed to the outside, it is easy to accurately couple the pivot bearing 130 to a predetermined position. However, since the thrust holder 150 is installed inside the housing 120, it is difficult to accurately couple the thrust holder 150 to a predetermined position. Thus, the thrust holder 150 is coupled to the cover plate 140, and the cover plate 140 is coupled to the housing 120 to determine the position of the thrust holder 150. By the way, when the tolerance and the coupling tolerance of the cover plate 140 itself is out of the set value, the thrust holder 150 is also out of the predetermined position, the center of the thrust holder 150 is coaxial with the center of the pivot bearing 130 Can't be located in

The stepping motor according to the present embodiment inserts and couples the thrust holder 150 to the cover plate 140 and the first tooth yoke 174 concentric with the housing 120, so that the thrust holder 150 is accurately positioned. To be combined. That is, the thrust holder 150 is concentrically coupled with the cover plate 140 and the first tooth yoke 174, which will be described with reference to FIGS. 2 and 3.

3 is an exploded perspective view of the main part shown in FIG. 2, wherein the cover plate 140, the elastic member 180, the thrust holder 150, and the housing 120 shown in FIG. 2 are rotated 90 ° counterclockwise. Is an exploded perspective view of the.

As shown, the cover plate 140 has a ring-shaped body 141 that contacts the side of the first tooth yoke 174 and covers the other side of the housing 120. A locking protrusion 143 is bent on one side of the outer circumferential surface of the body 141, and a locking groove 123 is formed on the outer surface of the housing 120. Because the locking protrusion 143 is inserted into the locking groove 123 and caught, the cover plate 140 is coupled to the housing 120. A coupling protrusion 145 is formed on the outer circumferential surface of the body 141, and a mounting groove 125 to which the coupling protrusion 145 is coupled is formed at the other side of the housing 120. When the cover plate 140 is coupled to the housing 120 such that the coupling protrusion 145 is inserted into the seating groove 125, the cover plate 140 is coupled to a predetermined position of the housing 120. In addition, a protruding tube 147 is formed at the center of the cover plate 140, and a coupling hole 149 is formed at an end of the protruding tube 147.

The thrust holder 150 has a body 151, a coupling protrusion 153, a coupling pipe 155, and a protruding frame 157. The body 151 is provided in a ring shape and contacts the outer surface of the first tooth yoke 174, and the engaging protrusion 153 is provided on the side of the body 151 so as to correspond to a gap between the tooth 174b and the tooth 174b. And is inserted and coupled between the tooth 174b and the tooth 174b. In addition, the coupling pipe 155 is formed to protrude from the inner peripheral surface of the body 151 is inserted and coupled to the coupling hole 149 of the cover plate 140, the outer peripheral surface of the body 151 is inserted into the inner peripheral surface of the protrusion pipe 147 Combined. When the body 151 and the coupling pipe 155 are respectively inserted into the protruding pipe 147 and the coupling hole 149 to couple the thrust holder 150 to the cover plate 140, the thrust holder 150 is positioned at a predetermined position. To be combined. Protruding frame 157 is formed on the outer surface of the body 151 in the same direction as the coupling pipe 155, which will be described later. Then, the ball 137 is built in the coupling pipe 155.

The body 151 and the coupling pipe 155 of the thrust holder 150 are inserted into and coupled to the protruding pipe 147 and the coupling hole 149 of the cover plate 140, and the coupling protrusion 153 is connected to the first tooth yoke ( 174 is coupled between the tooth 174b and the tooth 174b. In addition, since the cover plate 140 and the first tooth yoke 174 are coupled to each other concentrically with the housing 120, the thrust holder 150 is coupled to the cover plate 140 and the first tooth yoke 174. When the thrust holder 150 is also concentric with the housing 120. At this time, when the cover plate 140 or the first tooth yoke 174 is out of a predetermined engagement position due to the tolerances or the coupling tolerances of the cover plate 140 and the first tooth yoke 174 itself, the thrust holder 150 Is not coupled to a part that is outside the defined engagement position, so it is always correctly coupled to the specified position.

The elastic member 180 is provided as a coil spring and is installed between the cover plate 140 and the thrust holder 150. More specifically, the elastic member 180 is inserted between the coupling pipe 155 and the protruding frame 157 so that one side is in contact with the body 151 of the cover plate 150 and the other side is the body of the thrust holder 140 ( 141). That is, since the elastic member 180 is not exposed to the outside, the elastic member 180 is not deformed or damaged by external factors.

The stepping motor according to the present embodiment is provided with an end cover 190 for more accurately coupling the thrust holder 150, the end cover 190 has a body 191 and the coupling tube 195.

The body 191 of the end cover 190 is provided in a ring shape and the inner surface contacts the side surface of the first tooth yoke 174, and the outer surface contacts the body 141 of the cover plate 140. In addition, the coupling pipe 195 of the end cover 190 is formed to protrude from the inner circumferential surface of the body 191 is inserted into the protrusion pipe 147 of the cover plate 140, the coupling pipe of the thrust plate 150 on the inner circumferential surface ( 155 is inserted and coupled. At this time, the communication hole communicating with the coupling hole 149 of the cover plate 140 on the upper surface of the coupling pipe 195 of the end cover 190 so that the coupling pipe 155 of the thrust plate 150 can enter and exit ( 195a) is formed. The communication hole 195a is formed to correspond to the coupling hole 149.

In the structure in which the end cover 190 is installed, since the coupling position of the thrust holder 150 is confirmed by the tooth yoke 174, the end cover 190, and the cover plate 140, the thrust holder 150 is more accurately coupled. . The elastic member 180 is interposed between the end cover 190 and the thrust holder 150.

As described above, in the stepping motor according to the present invention, thrust holders are inserted into and coupled to the two yoke, the end cover, and the cover plate while being concentric with the housing. That is, since the coupling position of the thrust holder is confirmed in duplicate by the tooth yoke, the end cover and the cover plate, the thrust holder is always correctly coupled to the predetermined position. Therefore, the lead screw is always installed concentrically with the thrust holder and the tooth yoke, thereby improving the reliability of the product.

 Further, since the elastic member is installed between the cover plate and the thrust holder or between the end cover and the thrust holder so that the elastic member is not exposed to the outside, there is no fear that the elastic member is deformed or damaged by the inflow of foreign matter or an external object.

In the above, the present invention has been described in accordance with one embodiment of the present invention, but those skilled in the art to which the present invention pertains have been changed and modified without departing from the spirit of the present invention. Of course.

Claims (8)

A bracket having a support plate and first and second side plates formed at both end sides of the support plate; A lead screw installed to rotate forward and backward through the first side plate; A rotor fixed to an outer circumferential surface of one end of the lead screw; A housing coupled to the first side plate to surround the rotor; A stator coupled to the inside of the housing in a form of enclosing the rotor and acting on the rotor to rotate the rotor; A cover plate coupled to the housing and concentric with the housing; A thrust holder coupled to the cover plate and the stator to be movable in the longitudinal direction of the lead screw, concentric with the cover plate, and having one end side of the lead screw supported; A pivot bearing coupled to the second side plate to be concentric with the thrust holder and to support the other end side of the lead screw: And a resilient member provided between the cover plate and the thrust holder to elastically support the thrust holder. The method of claim 1, Stepping motor, characterized in that the elastic member is a coil spring. The method of claim 1, Stepping motor, characterized in that the thrust holder and the pivot bearing is provided with a ball in contact with one end and the other end of the lead screw. The method of claim 1, The cover plate is coupled to the body covering the other side of the housing, the engaging protrusion formed in the outer circumferential surface of the body to be caught in the engaging groove formed in the housing, extending from the outer circumferential surface of the body and seated in the seating groove formed in the housing Stepping motor comprising a projection, a protruding tube extending from the body, the coupling hole formed in the end of the protruding tube. The method of claim 4, wherein The thrust holder is a body in contact with the outer surface of the tooth yoke of the stator, a coupling protrusion formed on one surface of the body is inserted and coupled between the tooth and the tooth of the tooth yoke, extending from the other surface of the body and the ball is built Stepping motor characterized in that it has a coupling pipe which is inserted and coupled to the coupling hole at the same time, protruding from the outer surface of the body in the same direction as the coupling pipe. The method of claim 5, Stepping motor, characterized in that the body of the thrust holder is inserted into the protruding tube of the cover plate. The method of claim 6, Stepping motor, characterized in that between the cover plate and the thrust holder is further provided with an end cover coupled to the cover plate and the thrust holder to confirm the position of engagement of the thrust holder. The method of claim 7, wherein The end cover has an inner surface in contact with the tooth yoke and an outer surface in contact with the body of the cover plate, and protrudes from the body of the end cover and is inserted into the protruding tube of the cover plate, and the inner tube has a coupling tube of the thrust plate. Stepping motor, characterized in that the insertion hole is coupled to the upper surface has a communication hole through which the coupling tube of the thrust plate in and out corresponding to the coupling hole of the cover plate.

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