JP4045238B2 - Optical pickup feeder - Google Patents

Description

  The present invention relates to an optical pickup feeding device mounted on a disc player or the like.

In the disc players described in Patent Documents 1 and 2, the power transmission to the optical pickup moving mechanism is cut off at times other than when the optical pickup is driven to drive. If the power transmission is cut off and the optical pickup is allowed to move freely when the optical pickup is not driven, it becomes difficult to hold the optical pickup at a predetermined standby position. In addition, even if the power is connected, there is no appropriate resistance, so the feeding and stopping operations are not stable due to play between the machine parts such as gear backlash.
In order to cope with such a problem, in the disc player described in Patent Document 2, “the spring 207 is a helical spring, one end of which is fixed to the main body chassis by the fixing portion 213, and the other end is the arm 203. The optical pickup 209 is stretched along with the movement of the optical pickup 209 in the direction of arrow C and urges the optical pickup 209 in the direction of arrow G along the main shaft 205 (paragraph 0011 in Patent Document 2).

Even in the implementation of the disc player described in Patent Document 1, by providing a tension coil spring that pulls the optical pickup in the inner circumferential direction, the optical pickup is held at the standby position on the inner circumferential side when the power is cut off, and the backlash is reduced when the power is connected. There is an embodiment in which the feed operation and the stop operation are stabilized by killing.
Further, any part of the moving body mounted with the optical pickup that is urged by the tension coil spring and enters the standby position is pressed against the switch that detects that the optical pickup is in the standby position, and the switch is turned on. There are embodiments that are designed to do this. In this embodiment, when the optical pickup is in the standby position on the inner peripheral side, the switch is pressed and the elastic force that can be stably stopped is applied by the spring, so that the optical pickup is at the outermost peripheral side. The elasticity of the spring increased accordingly.
JP 2002-288911 A JP 2001-297544 A

In the above prior art, if the position of the optical pickup is different in the feeding operation of the optical pickup, the extension of the spring varies. The elastic force of the spring changes in proportion to the extension of the spring, and the force applied by the spring to the optical pickup varies depending on the position of the optical pickup.
In such a prior art, the accuracy and stability of the feed operation and the stop operation are hindered due to fluctuations in the spring load in the feed operation. There is a problem that it is difficult to perform control due to the complicated setting of control values and the need to cope with changes in spring elasticity over time.
In addition, when the driving device cannot cope with the maximum load of the spring, the optical pickup cannot be sent to the position to be moved, and on the other hand, the driving device is output so that torque corresponding to the maximum load of the spring can be output. In the case of the configuration, there is a problem that the servo motor and the power transmission mechanism are enlarged. In the embodiment in which the above-described switch is pushed by the elastic force of the spring, the maximum load of the spring becomes large, and this problem becomes remarkable accordingly.

  The present invention has been made in view of the problems in the prior art described above, and the load fluctuation is reduced, the difficulty of control associated with the load fluctuation is reduced, and the drive device is complicated to cope with an excessive load. It is an object of the present invention to provide an optical pickup feeding device in which an optical pickup feeding operation and a stopping operation are accurately and stably performed without increasing the size.

The invention according to claim 1 for solving the above-mentioned problem comprises an elastic member that generates a resistance against a certain movement of the optical pickup regardless of the position of the optical pickup within a predetermined movement range of the optical pickup , The elastic member is an optical pickup feeding device that urges the optical pickup in the moving direction away from the predetermined moving range outside the predetermined moving range .

According to a second aspect of the invention, it comprises an elastic member that applies an elastic force to the surface of the parallel moving body in the moving direction of the moving unit incorporating the optical pickup within a predetermined movement range of the optical pickup, wherein the elastic member A light characterized in that an elastic force is applied to an end face in the moving direction of the moving body outside the predetermined moving range to urge the moving body in the moving direction and away from the predetermined moving range. It is a pickup feeding device.

According to a third aspect of the present invention, the elastic member includes an elastic member that applies an elastic force to a peripheral surface of a gear connected to a moving body on which the optical pickup is mounted within a predetermined movement range of the optical pickup, and the elastic member is the predetermined member. An optical pickup feeding device characterized in that an elastic force is applied to an end face in the rotational direction of the gear outside the moving range to bias the moving body in the moving direction and away from the predetermined moving range. is there.

The invention of claim 4, wherein the one one of claims 1 to 3, characterized in that the object scanning range of the optical pickup is set within the predetermined range of motion or the predetermined movement range The optical pickup feeding device according to the above.

The invention according to claim 5 is the optical pickup feeding device according to any one of claims 1 to 4 , wherein the elastic member is a torsion coil spring.

A sixth aspect of the present invention is the optical pickup feeding device according to any one of the first to third aspects , wherein the elastic member is a single torsion coil spring.

The invention of claim 7, wherein, when the elastic member is biased away the optical pickup, according to claim from claim 1 to which power for an optical pickup movement is characterized in that it is cut 3 The optical pickup feeding device according to any one of the above.

  According to the present invention, since the elastic member is provided, the load fluctuation due to the position of the optical pickup is reduced within the predetermined movement range, the difficulty of control is reduced, and the excessive load is eliminated by equalizing the load. Thus, there is no need to complicate and increase the size of the drive device for dealing with an excessive load, and there is an effect that the feeding operation and the stopping operation of the optical pickup are stabilized with high accuracy.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following is one embodiment of the present invention and does not limit the present invention. The following embodiment will be described as an example applied to a disc player.

[First Embodiment]
FIG. 1 is a plan view showing the main components of the optical pickup feeding apparatus according to the first embodiment, and shows a state during standby of the optical pickup. For ease of explanation, the disk center O, the point P, and the coordinate axis X are shown in FIG.

  As shown in FIG. 1, the optical pickup feeding device of this embodiment includes an optical pickup 1, a carriage 2, a rack 3, a main shaft 4, a drive gear 5, a gear A6, a gear B7, and a torsion coil spring 8. And a switch 9.

  An optical pickup 1 is mounted on the carriage 2. A through hole is formed in the base end portion of the carriage 2, and the main shaft 4 is inserted into the through hole, whereby the carriage 2 is held by the main shaft 4 and guided by the main shaft 4 to be movable. A rack 3 is fixed to the carriage 2. The rack 3 is arranged in parallel with the main shaft 4. A gear B7 meshes with the rack 3, and a gear A6 meshes with the gear B7. As shown in FIGS. 2 and 3, the rack 3 has a side surface 3 a disposed in parallel with the main shaft 4 in the longitudinal direction of the rack itself, a fixed side end surface 3 b perpendicular to the main shaft 4, and an angle with respect to the main shaft 4. The arranged free end side inclined surface 3c is formed. The free end side inclined surface 3c is pressed against the switch 9 and the switch 9 is turned on, and it is detected that the optical pickup is in the standby position (innermost circumferential position in this embodiment).

  The drive gear 5 is rotationally driven by a motor (not shown). The drive gear 5 has a tooth row 5a and a notch 5b arranged on a circular arc in a part of the outer periphery. When the tooth row 5a faces the gear A6, the drive gear 5 and the gear A6 are meshed and connected, and when the notch 5b faces the gear A6, the connection between the drive gear 5 and the gear A6 is released. If the drive gear 5 and the gear A6 are meshed and connected, the power for moving the optical pickup 1 is mechanically connected. If the connection between the drive gear 5 and the gear A6 is released, the optical pickup 1 is moved. Is powered off mechanically.

The torsion coil spring 8 is fixed by inserting a fixing pin 11 into a coil portion and engaging both ends (arms) of the wire with the fixing pin 10 and the rack 3, respectively. One arm may be fixed to the fixing pin 10, but the other arm is in contact with the rack 3.
Generally, a coil spring is referred to as a tension coil spring and a compression coil spring, respectively, when used in a form that receives a tensile load and a compression load in the direction of the central axis of the coil. On the other hand, the torsion coil spring refers to a coil spring that is used in a form that receives a torsional moment load around the central axis of the coil. Usually, both ends of the strands of the tension coil spring form hooks on the central axis, and both ends of the strands of the compression coil spring form end turns. Normally, as shown in FIG. 1, arms are formed at both ends of the strand of the torsion coil spring so as to extend from the winding start point and end point in the tangential direction of the coil.

Point P is a point marked at the tip of the carriage 2 for convenience of explanation. When the optical pickup 1 is at the innermost standby position, it is defined that the X coordinate of the point P is X0, and X = X0.
When X = X0 to X1, the torsion coil spring 8 acts on the fixed-side end surface 3b of the rack 3 to urge the moving body on which the optical pickup 1 is mounted in the inner circumferential direction, that is, in the negative X direction.
When X = X1 to X2, by a torsion coil spring 8 acting on the side surface 3 a of the rack 3, the elastic force in a plane parallel to the moving direction of the moving unit incorporating the optical pickup 1 (= X axis direction) Make it work. Thereby, the moving body on which the optical pickup 1 is mounted receives a load perpendicular to the moving direction (X-axis direction) from the torsion coil spring 8. Therefore, when X = X1 to X2, a certain resistance to the movement of the optical pickup 1 occurs regardless of the position of the optical pickup 1. Since this resistance does not fluctuate and is constant, the position of the optical pickup 1 can be easily controlled with a constant driving voltage. This resistance force stabilizes the position of the optical pickup 1 at the time of stopping and moving, and the feeding operation and the stopping operation are accurately stabilized.

The range X0 to X2 corresponds to the movable range of the optical pickup 1, the range X1 to X2 corresponds to the predetermined movement range, and the range X0 to X1 is away from the predetermined movement range (= negative direction of X) ) Corresponds to the range to be energized.
The disk scanning range by the optical pickup 1 is set in the range X1 to X2 or the range X1 to X2. As a result, the disk scanning is accurately stabilized throughout and the reliability is improved. The movable range X0 to X2 may be set as the disk scanning range, but it is not preferable because load fluctuations may occur between the range X0 to X1 and the range X1 to X2.

In the range of X0 <X <X1, the engagement / disengagement between the drive gear 5 and the gear A6, that is, the mechanical connection / disconnection of the power for moving the optical pickup is switched.
By energizing the optical pickup 1 in the negative X direction in the range X0 to X1, the optical pickup 1 is surely moved in the negative X direction even when the power is cut off, so that the standby position (X = X0) Is held stably. In the present embodiment, the power is mechanically disconnected. However, even in a structure in which the power is not mechanically disconnected but electrically disconnected, the optical pickup 1 is moved in the negative X direction by the torsion coil spring 8. In the configuration in which the optical pickup 1 is urged, play due to play of mechanical parts is prevented, so that the optical pickup 1 is stably held at the standby position (X = X0).

FIG. 2 is a plan view illustrating the state of the rack 3, the torsion coil spring 8 and the switch 9 extracted when X = X0. FIG. 3 is a plan view illustrating the rack 3, the torsion coil spring 8 and the switch 9 when X1 <X ≦ X2. It is the top view which extracted and drawn the state of.
As shown in FIG. 2, a force F2 is applied to the rack 3, the moving body on which the optical pickup is mounted is urged in the negative direction of X, and the switch 9 is pushed by the free end side inclined surface 3c to be turned on. Become.
As shown in FIG. 3, the force F <b> 1 acts on the rack 3 to generate a resistance force against the movement of the optical pickup 1. In the range X1 to X2, since the torsion angle of the torsion coil spring 8 is constant, the force F1 is constant, and a force F1 that does not vary depending on the position of the optical pickup 1 can be applied. As a result, the resistance force against the movement of the optical pickup 1 becomes constant, and the feeding operation and the stopping operation are stabilized with high accuracy without causing difficulty in control.
Since two forces F1 and F2 having different directions are applied by a single torsion coil spring, it is effective in reducing the number of parts and simplifying the mechanism.

[Other Embodiments]
In the first embodiment, in order to generate a certain resistance to the movement of the optical pickup 1 regardless of the position of the optical pickup 1 within a predetermined movement range (X1 to X2) of the optical pickup 1, The elastic force of the torsion coil spring 8 as an elastic member was applied to the surface 3a of the moving body parallel to the moving direction of the moving body on which 1 is mounted. In the following second and third embodiments, the elastic force of the torsion coil spring is applied to the peripheral surface of the gear C7a that is connected to the moving body on which the optical pickup 1 is mounted so as to be able to transmit power in order to generate the resistance. .

FIG. 4A is a plan view of the second embodiment, and FIG. 4B is a plan view of the third embodiment, both of which are different from the first embodiment.
In the second and third embodiments, a gear C7a is used instead of the gear B7 of the first embodiment. On one side surface of the gear C7a, an arc-shaped rib 7a-1 centering on the center of the gear is formed.
As shown in FIG. 4A, in the second embodiment, one arm of the torsion coil spring 8a is brought into contact with the rib 7a-1, and the torsion coil spring 8a is fixed to the outside of the gear C7a by the fixing pins 12 and 13.
As shown in FIG. 4B, in the third embodiment, one arm of the torsion coil spring 8b is brought into contact with the rib 7a-1, and the coil spring 8b is fixed inside the gear C7a by the fixing pins 14 and 15. The fixing pin 15 may be shared with the shaft of the gear C7a. The fixing pin 14 does not rotate together with the gear C7a, and the tip protrudes toward the side surface on the rib 7a-1 forming side of the gear C7a to the extent that it does not contact the gear C7a, and the base end is fixed to the frame or the like. is there.
In the rack 30 applied to the second and third embodiments, it is not necessary to provide the side surface 3a and the fixed-side end surface 3b suitable for spring contact as in the first embodiment.

In the second embodiment, by applying the torsion coil spring 8a to the outer peripheral surface of the rib 7a-1, a force F1 'in place of the force F1 of the first embodiment is applied, and the torsion coil spring 8a is moved to the rib. By acting on one end face of 7a-1, a force F2 'in place of the force F2 of the first embodiment is applied.
In the third embodiment, by applying the torsion coil spring 8b to the inner peripheral surface of the rib 7a-1, a force F1 "in place of the force F1 of the first embodiment is applied, and the torsion coil spring 8b is By acting on the one end surface of the rib 7a-1, a force F2 "in place of the force F2 of the first embodiment is applied.

The force F1 ′ in the second embodiment and the force F1 ″ in the third embodiment are constant regardless of the position of the optical pickup 1 within a predetermined movement range (X1 to X2) of the optical pickup 1. The resistance against the movement of the optical pickup 1 is generated.
In the second embodiment, the optical pickup 1 is urged in the negative X direction in the range X0 to X1 by the force F2 ′ in the third embodiment and the force F2 ″ in the third embodiment. Similarly, the optical pickup is stably held at the standby position (X = X0).

The torsion coil spring 8a (8b) may be provided not only for the gear C7a directly connected to the rack 30, but also for a gear (for example, gear A6) indirectly connected to the rack 30 via another gear. .
In the second and third embodiments, the forces F1 ′ and F1 ″ do not act directly on the moving body on which the optical pickup 1 is mounted. Therefore, the backlash between the gear C7a and the rack 30 causes the feeding operation and the stopping operation accuracy. While the stability is reduced, there is an advantage that the degree of freedom of the installation location of the spring is increased.
On the other hand, in the first embodiment, since the force F1 directly acts on the moving body on which the optical pickup 1 is mounted, the force F1 suppresses the behavior of the moving body and the accuracy and stability of the feeding operation and the stopping operation. Has the advantage of better.

In the above embodiment, the torsion coil spring is used as the elastic member. However, the present invention is not limited to this, and the elastic member may be a coil spring such as a compression coil spring or a tension coil spring, or a spring other than a coil spring such as a plate spring. An elastic member other than a so-called spring (for example, rubber, sponge, etc.) may be used. Since bending springs such as leaf springs and torsion coil springs can be configured such that the direction of reaction force varies depending on the amount of deformation, a simple and advantageous structure as in the above embodiment can be realized.
In the above embodiment, force F1 (force F1 ′, force F1 ″) and force F2 (force F2 ′, force F2 ″) are applied. However, the present invention is not limited to this, and force F1 (force Any elastic member can be simply configured as long as only the force F1 (force F1 ′, force F1 ″) is applied.

In the above embodiment, the standby position of the optical pickup is the inner peripheral side of the disc installed in the disc player, but the standby position may be the outer peripheral side. In an optical pickup device other than a disc player, there may be cases where the concept of the inner peripheral side and the outer peripheral side does not exist. Even in such a case, the above embodiment can be implemented with one end of the movement range of the optical pickup as a standby position. Further, the present invention can be applied to those in which the standby position of the optical pickup is not determined and in which the power to the optical pickup is not cut off during operation, and is technically effective.
The optical pickup feeding device of the present invention can be widely applied to a disk player having an optical pickup feeding device and an optical pickup device other than the disk player in addition to the disc player of Patent Document 1.

FIG. 2 is a plan view showing the main components of the optical pickup feeding device according to the first embodiment of the present invention, and shows a state during standby of the optical pickup. FIG. 2 is a plan view illustrating the rack 3, the torsion coil spring 8, and the switch 9 extracted when the X coordinate of a point P in FIG. 1 is X0. FIG. 2 is a plan view illustrating the state of a rack 3, a torsion coil spring 8 and a switch 9 extracted when the X coordinate of a point P in FIG. 1 is X1 <X ≦ X2. (A) is a plan view of the second embodiment of the present invention, (b) is a plan view of the third embodiment of the present invention, and both depict parts different from the first embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical pick-up 2 ... Carriage 3 ... Rack 4 ... Main shaft 5 ... Drive gear 6 ... Gear A
7 ... Gear B
8 ... Torsion coil spring 9 ... Switch

Claims (7)

An elastic member that generates resistance against movement of a certain optical pickup regardless of the position of the optical pickup within a predetermined movement range of the optical pickup is provided , and the elastic member moves the optical pickup outside the predetermined movement range. The optical pickup feeding device is urged in a direction away from the predetermined movement range . An elastic member that applies an elastic force to a surface of the moving body that is parallel to the moving direction of the moving body on which the optical pickup is mounted within a predetermined movement range of the optical pickup, and the elastic member is outside the predetermined movement range; An optical pickup feeding device characterized in that an elastic force is applied to an end surface of a moving body in a moving direction to urge the moving body in the moving direction and away from the predetermined moving range . An elastic member that applies an elastic force to a peripheral surface of a gear connected to a moving body on which the optical pickup is mounted within a predetermined movement range of the optical pickup, and the elastic member rotates the gear outside the predetermined movement range. An optical pickup feeding device characterized in that an elastic force is applied to an end face in a direction to urge the moving body in the moving direction and away from the predetermined moving range . Optical pickup feeding apparatus according to any one of claims 1 to 3, characterized in that the object scanning range of the optical pickup is set within the predetermined range of motion or the predetermined movement range. The elastic member is an optical pickup feeding device as claimed in any one of claims 1 to 4, characterized in that a torsion coil spring. The optical pickup feeding device according to any one of claims 1 to 3, wherein the elastic member is a single torsion coil spring. When the elastic member is urged away said optical pickup, from claim 1, the power for the optical pickup movement is characterized in that it is cut according to any one of claims 3 Optical pickup feeder.

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