JPS6387643A - Optical disk replacing device - Google Patents

Abstract

PURPOSE:To reduce a required output torque of a driving source to make a motor small-sized and light-weight and use a narrow bar-shaped shaft as the supporting shaft by supporting a carriage with at least one or more constant torque springs. CONSTITUTION:Constant torque springs 17 are wound around drums 16, and they always support the weight of a carriage 4 with a certain torque because being expanded and contracted in accordance with vertical movement in the perpendicular direction of the carriage 4. Therefore, the required output torque of the driving source which rotates a ball screw 5 is reduced. The weight of the carriage 4 is supported by the restoring force of constant torque springs 17 in such a manner, and the torque due to the weight of the carriage 4 does not act upon drums 16, namely, supporting shafts 14, and only the frictional torque on the contacting surface between drums 16 and supporting shafts 14 due to rotation of drums 16 accompanied with expansion and contraction of constant torque springs 17 acts upon them. Thus, it is unnecessary to increase the rigidity of supporting shafts 14, and narrow bar-shaped shafts can be used as them.

Description

[Detailed description of the invention] Technical field The present invention relates to an optical disc exchange device.

2. Description of the Related Art Conventionally, there is an autochanger-type optical disk changing device as shown in FIG. 5, which selects an arbitrary optical disk and automatically loads it into a recording/reproducing drive device. First, a stocker 2 is provided with a plurality of cartridges 1 each containing an optical disk (not shown), and has a shelf configuration in which these cartridges 1 are individually stored in a horizontal state.
is provided. A drive device 3 for recording or reproducing an optical disc is provided in this section. Furthermore, the optical disc of the stocker 2 (
Cartridge l) Use the drawer 1 to move vertically between the front surface of the stocker 2 and the front surface of the drive device 3 to pull out the optical disc from the desired position of the stocker 2 and transport it to the drive device 3, or to set it in the drive device 3. A carriage 4 is provided for pulling out the stocker 2 and transporting and storing it to a desired position in the stocker 2. Here, the carriage 4 is erected on the back side, guides the movement of the carriage 4 in the vertical direction, and is slid in the vertical direction by a ball screw 5 which is rotationally driven. That is,
The ball screw 5 serves as a driving force transmission medium, and is connected via a pole nut 6 for converting the rotation of the ball screw 5 into vertical movement of the carriage 4.

Such a carriage 4 needs to detect and position its position, and a linear encoder slit plate 7 is provided vertically along the moving direction of the carriage 4. A plurality of slits 8 formed at the same intervals as the carriage 4 are detected by an optical sensor 9 attached to the carriage 4.
The position detection and positioning are performed. However, in this method, the sensor 9 is moved and displaced together with the carriage 4, and the wiring lead wire for the sensor 9 also needs to be long enough to be bent, and the output signal from the sensor 9 is likely to contain noise. Become something.

A balancing weight 10 is provided to mutually cancel out the weight of the carriage 4 moving in the vertical direction by the ball screw 5. Connected and supported.

Here, the inertial body acceleration torque, which is part of the required output torque of the drive source for moving the carriage 4, is the product of the moment of inertia and the required acceleration, and the balancing weight 10 is connected to the moving body (i.e., the carriage 4 and Cartridge 1
) has the same mass as the mass of As a result, the moment of inertia of the inertial body acceleration torque is twice the moment of inertia of the moving body, and the load on the drive source is large. That is, the drive source for moving the carriage 4 needs to be capable of accelerating the moment of inertia of the carriage 4 and the balancing weight 10, and in the case of the conventional method, the required output torque of the drive source becomes large. Furthermore, in the case of such a balancing weight system, since the weight of both the carriage 4 and the balancing weight 10 acts on the support shaft 13 of the pulley 12, the support shaft 13 needs to have sufficient rigidity.

Purpose The present invention was made in view of the above points, and it is possible to reduce the required output torque of the drive source for moving the carriage in the vertical direction, thereby reducing the size and weight of the motor. It is an object of the present invention to provide an optical disk exchange device in which a support shaft that indirectly supports the optical disc can be made into a thin rod-like support shaft.

Structure In order to achieve the above object, the present invention includes: a stocker that individually stores optical discs stored in each cartridge; a drive device that records or plays back the optical disc;
An optical disc exchange device comprising a carriage that selectively grips the optical disc and moves the optical disc in a vertical direction between the stocker and the drive device, wherein the carriage is supported by at least one constant torque spring. It is characterized by the fact that

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. The same parts as those shown in FIG. 5 are indicated using the same reference numerals. First, two support shafts 14 are provided above the carriage 4 and are supported by an apparatus main body 15, and two bobbin-shaped drums 16 are rotatably attached to each of these support shafts 14. . these drums 1
6 are each wound with a constant torque spring 17 and housed therein.

Here, the constant torque spring 17 is a leaf spring,
Four of them are provided and connected to the carriage 14. That is, these four constant torque springs 17 expand and contract as the carriage 4 moves in the vertical direction to support the weight of the carriage 4. Here, the constant torque spring 17 and the carriage 4 are connected through a stopper 18, as shown in FIGS. 2 and 3. That is, the stopper 18 and the constant torque spring 17 are fixedly connected by a rivet 19, and the stopper 18 is connected and fixed to the carriage 4 by a fixing screw 20.

Further, one of the constant torque springs 17, for example, the constant torque spring 17a, is formed with a plurality of slits 21 (marks or the like may be divided by means) at a pitch equal to the pitch of the storage shelves of the stocker 2. An optical sensor 22 for detecting the slit 21 is provided in a fixed position with respect to the constant torque spring 17a.

In such a configuration, in order to move the carriage 4 to the storage position of any optical disk (cartridge 1) stored in the stocker 2, a driving force is applied to the ball screw 5 through the rotation 6 by a driving source such as a motor. is transmitted and moves up and down in the vertical direction, and its weight is always supported by constant torque from four constant torque springs 17 whose one ends are fixed to the carriage 4. Here, as the carriage 4 moves up and down, the constant torque spring 17 also expands and contracts. At this time, the sensor 22 for the constant torque spring 17a counts the number of slits 21 moved due to the expansion and contraction of the constant torque spring 17a. Since the number of sheets counted by this sensor 22 is proportional to the amount of movement of the carriage 4, the position of the carriage 4 can be detected at all times, and the width of the slit 21 is set at the same vertical position as the storage position of the target optical disk cartridge 1 of the carriage 4. By making the positioning accuracy equal to the positioning accuracy during positioning, the carriage 4 can be positioned within such positioning accuracy. Then, the rotation of the ball screw 5 is stopped at the target optical disc position. At that position, the carriage 4 receives the cartridge 1 containing the target optical disk from the stocker 2, moves the carriage 4 upward in the same way, and drives the drive device 3.
The cartridge 1 is loaded into the cartridge insertion position of the drive device 3 at the location. This is the basic operation for transporting and loading any optical disc from the stocker 2 to the drive device 3.

Similarly, when moving the cartridge 1 from the drive device 3 to the empty storage shelf of the stocker 2, the carriage 4 is positioned in the same vertical position as the cartridge ejection position of the drive device 3, and the cartridge 1 is moved from the drive device 3 to the empty storage shelf of the stocker 2.
The carriage 4 is moved and positioned to the same vertical position as the empty storage shelf of the stocker 2, and the cartridge 1 is stored in the empty storage shelf.

In such an operation, according to this embodiment, the weight of the carriage 4 is always supported by the four constant torque springs 17. That is, each constant torque spring 17
Since it expands and contracts as the carriage 4 moves up and down in the vertical direction, it always supports the weight of the carriage 4 with a constant torque. Therefore, the required output torque of the drive source for rotating the ball screw 5 can be reduced. In addition, the weight of the carriage 4 is thus supported by the restoring force of the constant torque spring 17, and no torque due to the weight of the carriage 4 acts on the drum 16, and thus the support shaft 14, and the expansion and contraction of the constant torque spring 17 Only the friction torque at the contact surface between the drum 16 and the support shaft 14 due to the accompanying rotation of the drum 16 acts. Therefore, there is no need to increase the rigidity of the support shaft 14, and a thin rod-like support shaft may be used. Furthermore, a drive source carriage 4 for moving the carriage 4 is provided.
, the inertia moment of the constant torque spring 17 and the drum 16 can be accelerated, and the load on the drive source can be clearly reduced compared to the conventional one, and the motor can be made smaller and lighter.

Further, according to this embodiment, the position detection and positioning mechanism of the carriage 4 are also simple. That is, constant torque spring 17
Since the slit 21 is formed in the constant torque spring 17a, which is one of the constant torque springs 17a, and the sensor 22 detects it, there is no need to provide a completely separate linear encoder slit plate as in the past, and the device can be made smaller and the number of parts can be reduced. It becomes possible. or,
Since the sensor 22 may be fixed in position, this sensor 22
The wiring for the sensor is simple and short, and the noise of the sensor output can be reduced.

As shown in FIG. 4, such a detection method involves forming slits 23 on the flange 16a of the drum 16 at a predetermined pitch corresponding to the storage shelf pitch,
3 may be detected by a sensor 24 (position fixed). That is, since the drum 16 rotates according to the expansion and contraction of the constant torque spring 17 as the carriage 4 moves, if the slit 23 of the flange lea of the drum 16 is detected by the sensor 24, the position of the carriage 4 can be detected and positioned. It can be done.

The sensor is not limited to an optical one.

Effects As described above, in the present invention, since the carriage that moves up and down in the vertical direction is supported by a constant torque spring, the carriage that moves up and down can always be supported in a constant torque state, and therefore the required output of the drive system for moving the carriage is reduced. By reducing the torque, the motor can be made smaller and lighter, and there is no need to increase the rigidity of the support shaft that indirectly supports the carriage, so a thin rod-like one can be used. be.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention,
Fig. 1 is an external perspective view, Fig. 2 is a side view, Fig. 3 is a partially enlarged perspective view, Fig. 4 is a perspective view of a modified example, and Fig. 5 is an external perspective view of a conventional example. It is a diagram. 1...Cartridge, 2...Stocker, 3...
Drive device, 4... Carriage, 17... Constant torque spring Applicant Ricoh Co., Ltd. -13

Claims (1)

[Claims] a stocker that individually stores optical discs housed in cartridges; a drive device that records or plays back the optical disc; and a drive device that selectively grips the optical disc and moves it vertically between the stocker and the drive device. What is claimed is: 1. An optical disk exchanging apparatus comprising: a carriage for transporting the optical disk; the carriage being supported by at least one constant torque spring;