JPH0418112Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention is designed to operate the disk tray of a digital audio disc (abbreviation: CAD) player, which is mainly called a compact disc (abbreviation: CD) player, by using a direct current motor in the forward and reverse directions. This device is used to move the player in and out of the playback position by means of a motor, and is also used to set up video discs, video cassettes, and even cassette tapes in video tape recorders. The present invention relates to a loading device for an audio device configured to move a playback/recording medium such as a disk tray into and out of a predetermined position.

<Conventional technology> Devices of this kind that have been known in the past include: ○a. A device in which the rotational speed of the DC motor is kept constant throughout the entire period of medium movement in and out, and ○b. Air dump and oil dump. There is a device configured to perform speed convergence and fixed position stopping using a fluid shock absorbing device such as .

<Problems to be solved by the invention> However, it is difficult to set the speed of the constant speed moving type of the former (○). For example, if the speed is set to low to avoid unpleasant noises such as shock and gear noise, the loading time will be long and it will be difficult to use.On the other hand, if the speed is set to be high to make it easier to use, the inertia force when the movement stops will cause However, there are disadvantages in that the shock exerted on other mechanisms is large, and unpleasant noises such as gear noise may occur.

On the other hand, the latter type (○) can be set at high speed to improve usability and can absorb the shock when stopping and achieve a fixed position stop, but it requires a fluid shock absorber, which increases cost and space factors. Not only is there a disadvantage in terms of speed, but also the viscous resistance of the fluid changes depending on environmental conditions and over time, making the desired speed convergence and fixed position stopping performance unstable. It was hot.

<Means for Solving the Problems> In view of the above circumstances, the present invention aims to provide a device that can perform reliable and smooth loading without the need for additional parts, while maintaining a sufficiently high average speed. Have a purpose.

In order to achieve the above object, the loading device for audio equipment according to the present invention includes a mechanism that automatically controls the rotational speed of the DC motor so that the speed during the second half of the input/output movement is smaller than the speed during the first half. It is characterized by its configuration.

<Operation> When using the loading device according to the present invention having the above-mentioned configuration, the medium moves at high speed during the first half of the time by controlling the rotational speed of the DC motor, and moves at a lower speed during the second half of the time. . Therefore, if the high speed in the first half is set to a sufficiently large value, the overall average speed can be maintained relatively high despite the deceleration in the second half, and the low speed movement in the second half allows for less shock. This makes it possible to stop in position.

<Embodiment> An embodiment of the present invention will be described below in detail based on the drawings. In FIG. 1, reference numeral 1 is a motor that can be switched between forward and reverse directions. and playback of cassette tapes, etc.
The recording medium 2 is moved into and out of a predetermined position such as a playback position or a recording position, that is, it is loaded and unloaded. 3 is a mechanism that automatically controls the rotational speed of the DC motor 1 so that the speed V ₁ during the second half of the input/output movement is smaller than the speed V ₀ during the first half of the movement. The microcomputer 3A counts the length of time after the voltage V is applied, and when the time length counted by the microcomputer 3A reaches the set time length _T1 , the DC motor 1 receives that signal. As shown in Figure 2, the voltage applied to
This is a pulse control mechanism consisting of a driver 3B that switches to a rectangular pulse wave. As a result, the medium moving speed V is reduced from the speed V ₁ during the second half to half of the speed V ₀ during the first half, and the average speed V _A is
It becomes V ₀ +V ₁ /2.

FIG. 3 shows another example of pulse control, in which the pulse duty t when moving the medium in the latter half is reduced over time in the order of 2/3, 1/2, and 1/3. This is what I did.

<Effects of the invention> As is clear from the detailed explanation above, when the present invention is used, (1) the average speed of medium movement in and out can be made sufficiently large to provide good usability due to the loading time; However, (2) the actual speed at the time of stopping is kept small to suppress shocks caused by inertial force as much as possible, and it is possible to reliably stop at a fixed position.

(3) Moreover, it is advantageous in terms of cost and space factor because it does not require the use of any fluid buffering device such as an air dump; (4) Furthermore, there is no instability in performance due to changes in the viscous resistance of the fluid; To ensure reliable, smooth and stable loading as expected regardless of long-term use.

It has achieved many practical effects, such as:

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a graph explaining a control form, and FIG. 3 is a graph showing another control form. 1 is a DC motor, 2 is a playback/recording medium, and 3 is an automatic speed control mechanism.

Claims (1)

[Scope of utility model registration request] In a loading device for digital audio equipment configured to play back a disk tray, cassette tape, etc. and move a recording medium 2 in and out of a predetermined position by forward and reverse rotation of the DC motor 1, the rotation of the DC motor 1 A loading device for digital audio equipment, characterized in that a pulse control mechanism 3 is provided, which is configured to reduce the speed of the pulse duty during the second half movement in a plurality of steps over time after the start of the input/output movement. .