JPS6316494A - Disk reproducing device - Google Patents

Abstract

PURPOSE:To exactly protect a device as well as a pickup, by fixing a detecting element for detecting a dewdrop, onto a chassis. CONSTITUTION:A detecting element 31 for detecting a dewdrop is fixed to a prescribed position on a chassis 13 consisting of a material whose specific heat is comparatively high, such as iron, etc., and this position is in the vicinity of a position of a pickup 15 (a position where the pickup 15 is holding before starting a reproducing operation). The chassis 13 follows up a variation of the environment prior to the pickup 15 since its specific heat is high. That is, when humidity of the periphery becomes high, the chassis 13 is bedewed prior to the pickup 15, and on the other hand, when the humidity of the periphery becomes low, the dewdrop is dissolved later than the pickup 15. As a result, a state immediately before the dewdrop is generated actually in the pickup 15, and a state immediately after the dewdrop of the pickup 15 has been dissolved completely can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a disc playback device such as a vehicle navigation device.

[Summary of the invention]

In the present invention, a detection element for detecting dew condensation is fixed on the chassis.

[Conventional technology]

Recently, research has been conducted on vehicle navigation devices that play back map information recorded on a so-called CD-ROM or the like and display the current location of the vehicle to guide the vehicle to a predetermined destination, and some of them have been commercialized. Since such a device is installed in a vehicle, its operating conditions are more severe than those of ordinary CD players, video disc players, etc. used at home.

[Intermediate point that the invention attempts to solve]

In conventional devices, the detection element is fixed in a predetermined position on the housing to detect the usage conditions, but because the position is not appropriate, accurate conditions cannot be detected, and the device cannot be adequately protected. There was a drawback that it could not be done.

[Means for solving problems]

The present invention provides a disk playback device that includes a spindle motor that rotates a disk, a pickup that plays information from the disk, a slider motor that drives the pickup in the radial direction of the disk, and a spindle motor that supports the spindle motor, pickup, and slider motor. The pickup is characterized by comprising a chassis made of a material with a large specific heat, and a detection element fixed to the chassis in the vicinity of the pickup when it is at the home position and detects dew condensation.

[Effect]

A detection element for detecting dew condensation is fixed to a chassis supporting the pickup near the pickup at the home position.

〔Example〕

1 to 3 show the configuration of a disc reproducing apparatus according to the present invention. In the figure, 1 is a casing made of metal or the like, and the casing 1 has a plurality of pieces (in the embodiment, 4
) reinforcing parts 2 are added and reinforced. Reinforcement part 2
has a fixing plate 3 fixed to the side wall of the casing 1 by spot welding or the like, a side wall 4, and a top plate 5, and these and the side wall and bottom surface of the casing 1 form a substantially sealed space. It is formed. A chamfered portion 6 is formed on a portion of the side wall 4 to widen the space inside the housing 1.

11 is an insulator for damping vibration, and screw 12
It is fixed to the top plate 5 of the reinforcing part 2 by. A chassis 13 supports mechanisms such as a spindle motor 14 for rotating the disk 10, a pickup 15 for reproducing information from the disk 10, and a slider motor 16 for driving the pickup 15 in the disk radial direction. 17
．． Reference numeral 18 denotes a printed circuit board in which an electric circuit for controlling these mechanisms is incorporated, and its end located on the center side of the casing 1 is fixed to the chassis 13 with screws or the like. Since the chassis 13 that supports these mechanisms and the printed circuit boards 17 and 18 is supported by the insulator 11, the structure is such that vibrations from the casing 1 are difficult to be transmitted to these.

21 is a balance weight whose one end is fixed relatively to the outer periphery of the chassis 13, and each mechanism and the printed circuit board 17.1
The required number (three in the embodiment) is provided so that the mass of the chassis 13 supporting the insulators 8 is equally supported by the four insulators 11. balance weight 21
is provided so as to protrude below the chassis 13, and its lower end abuts the printed circuit board 17, 18 via a spacer 22 inserted as required. In other words, the printed circuit boards 17 and 18 are on the inside (center side of the housing 1)
The six balance weights 21, whose ends are fixed to the chassis 13 and have a so-called cantilevered structure, abut against the outer ends of the printed circuit boards 17 and 18 via the spacers 22, converting this cantilevered structure into a double-sided structure. It is said that As a result, when vibration is transmitted to the chassis 13, the printed circuit board 17.1
8 is prevented from vibrating and being damaged. The printed circuit boards 17 and 18 may be fixed to the balance weight 21 with screws or the like in order to ensure their support, but this will impair workability when mounting or removing them. You can just do it.

Mechanisms such as the spindle motor 14, pickup 15, slider motor 16, printed circuit boards 17, 18, and balance weight 21 are all arranged below the chassis 13. This allows the center of gravity of the mechanism supported by the insulator 11 to be lowered, which is effective in preventing vibration. The heights of the insulator 11 and the reinforcing portion 2 are set so that these mechanisms can be accommodated in the housing 1.

A detection element 31 detects dew condensation, and is fixed at a predetermined position on the chassis 13 made of a material with a relatively large specific heat, such as iron. As shown in FIG. 1, this position is near the home position of the pickup 15 (the position where the pickup 15 is waiting before starting playback operation). Since the chassis 13 has a large specific heat, it follows changes in the environment before the pickup 15 does. That is, when the surrounding humidity increases, dew condensation occurs before the pickup 15. On the other hand, when the surrounding humidity becomes low, condensation disappears after the pickup 15. As a result, it becomes possible to detect the state immediately before dew condensation actually occurs on the pickup 15 and the state immediately after the dew condensation on the pickup 15 is completely eliminated.

FIG. 4 shows a circuit diagram for protecting the device in response to the output of the detection element 31. In this embodiment, seven detection elements 31 for detecting dew condensation and a detection element 32 for detecting temperature are provided. The output of the detection element 31 is supplied to a comparison circuit 34, and the output of the detection element 32 is supplied to comparison circuits 35 and 36, respectively. Comparison circuit 34.3
5.36 each has a predetermined group +! ! Voltage V□, v2, ■,
is entered. Therefore, the comparison circuit 34 is activated when condensation occurs, the comparison circuit 35 is activated when the temperature reaches a predetermined value or higher, and the comparison circuit 36 is activated when the temperature becomes lower than a predetermined value.
Each outputs a high level detection signal.

These detection signals are sent to the detection circuit 33 via an OR circuit 37.
It is input to the regulator 38 as an output.

When a low-level signal is input from the detection circuit 33, the regulator 38 converts the voltage supplied from a battery (not shown) into a predetermined voltage (for example, 5V) and supplies it to a control circuit 39 consisting of a microcomputer or the like. ing. At this time, the control circuit 39 outputs a control signal to the converter 40, puts the converter 4o into operation, and generates a predetermined DC voltage (for example, ±5v, ±13v) from the DC voltage of the battery, and supplies it to each circuit, means, etc. let

When the regulator 38 receives a high level signal,
The supply of power to the control circuit 39 is stopped.

At this time, since control circuit 39 puts converter 40 into a non-operating state, the predetermined voltage is not generated from converter 4o. In other words, the entire disk playback device stops operating (of course, only the detection circuit 33 remains in operation), thus preventing the circuits, means, etc. of the disk playback device from running out of control or being destroyed.

When the normal state returns from the abnormal state, a low level signal is output from the detection circuit 33, so power is supplied to each circuit and means again as in the case described above.

Note that the output of the detection circuit 33 may be directly output to the converter 40 as a power supply circuit for control. It is also possible to input the output of the detection circuit 33 to the control circuit 39, so that the control circuit 39 itself is put into an operating state and the converter 40 is put into a non-operating state. In this way, it becomes possible to retain the information stored in the memory without erasing it. Of course, the converter 40 is also put into operation, and the control circuit 39
It is also possible to output a control signal from to each circuit, means, etc. to put each circuit, means, etc. in a standby state, but in that case, I
There is a possibility that it may not be possible to prevent C from running out of control. Therefore, it is preferable to control the converter 40 or provide a switch at its input or output stage so that power is not supplied to each circuit 1 means.

〔effect〕 As described above, the present invention relates to a disc playback device.

A spindle motor that rotates the disk, a pickup that reproduces information from the disk, a slider motor that drives the pickup in the radial direction of the disk, and a chassis made of a material with relatively high specific heat that supports the spindle motor, pickup, and slider motor. Since the device is provided with a detection element fixed to the chassis for detecting dew condensation in the vicinity of the pickup when it is at the home position, the device including the pickup can be reliably protected.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the disc playback device of the present invention, FIG. 2 is a front view thereof, FIG. 3 is a side view thereof, and FIG. 4 is a circuit diagram thereof. 1... Housing 2... Reinforcement part 3... Fixing plate 4... Side wall 5... Top plate 6... Chamfered part 10... Disc 11... Insulator 12... Screw 13...Chassis 14...Spindle motor 15...Pickup 16...Slider motor 17.18...Printed circuit board 21...Balance weight 22...Spacer 31.32...Detection element 33 ...Detection circuit 34.35.36...Comparison circuit 37...OR circuit 38...Regulator 39...Control circuit 40...Converter or higher

Claims (1)

[Claims] A spindle motor that rotates a disk, a pickup that reproduces information from the disk, a slider motor that drives the pickup in the radial direction of the disk, and a motor with relatively specific heat supporting the spindle motor, the pickup, and the slider motor. A disc playback device comprising: a chassis made of a large material; and a detection element fixed to the chassis in the vicinity of the pickup when the pickup is at a home position, and detects dew condensation.