JPH0861981A - Pattern forming method in position detector - Google Patents

Abstract

PURPOSE: To improve the general purpose applicability of a position detector by forming plural patterns by relating the necessary detecting positions of a mechanism with the coded signals formed of plural patterns. CONSTITUTION: Of plural patterns of the pattern disk 3 of a position detector 1, the number of patterns used selectively is reduced. At the same time, in compliance with the reduction of the using patterns, the number of contacts of a movable contact 4 is also reduced. As a result, when the number of the necessary detecting positions in a mechanism is reduced, the coded signal of one necessary detecting position in the mechanism, or the coded signals of the neighboring detecting positions of this position, including the one necessary detecting position, are formed in the coded signals different from the coded signals at the other necessary detecting positions. Consequently, the mechanism of an apparatus having many necessary detecting positions is used together with an apparatus having fewer necessary detecting positions. Even when the detector 1 is used commonly, the necessary detecting positions of the mechanism made unnecessary by reducing the number of pattern using the detector 1 are not detected, and the necessary detecting positions can be detected accurately, so as to improve the general purpose applicability of the detector 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position detector for detecting the position of a mechanism in a video tape recorder or the like, and particularly when the same position detector is used to detect a case where there are many detection positions of the mechanism and a case where there are few detection positions. The present invention relates to a pattern forming method in a position detector capable of accurate position detection even if the number of mechanism positions that need to be detected is reduced.

[0002]

2. Description of the Related Art Video tape recorders (hereinafter "VTR")
Say. ), FF (fast forward), PLA
It is necessary to detect the position of the mechanism according to the states such as Y (playback), REW (rewind), and STOP (stop).
Therefore, a pattern disk having a plurality of concentrically arranged contact patterns in which conductors that are on-states and insulators that are off-states are alternately arranged in advance, and each contact pattern on this pattern disk. And a movable contact that detects the on / off state of each contact pattern by simultaneously contacting the movable contact, and by rotating the movable contact (less than one rotation) in conjunction with the mechanism, the movable contact is moved according to the position of the mechanism. A position detector that outputs a coded signal that combines the on / off states of the contact patterns that simultaneously contact is used.

For example, as a position detector used in a high-performance VTR such as W-VHS / S-VHS, as shown in FIG. 6, four channels chA as shown in FIG.
.About.chD contact patterns and common channel chG patterns (the shaded portions in the drawing are in the off state, the other parts are in the on state) are provided on the pattern disk, and the channels chA to chD are shown in the same figure (b). So that output signals SA to SD which are on / off signals can be obtained,
By assigning positions P1 to P11 to the respective detection-required positions of the mechanism as shown in the figure, each detection-required position of the mechanism (the detection-required position is a “detection-needed position”).
Is the meaning of. ), A 4-bit coded signal is output individually.

Here, for example, the position P1 is changed to EJECT.
The (take-out) position and position P5 are set to MP-PLAY (W-VH
S tape playback) position so that when the on state is “0” and the off state is “1”,
A 4-bit coded signal such as "0100" (the order of chA to chD, the same applies hereinafter) is output at position P1 and "1110" at position P5.

[0005]

By the way, as a VTR, as shown in FIG. 6, it is possible to detect a small number of mechanism positions from a high-performance VTR such as W-VHS or S-VHS which requires detection of many mechanism positions. Some have various functions up to a low-function VTR such as a normal VHS having only the basic functions that are sufficient. In this case, regardless of the function of the VTR, it is desirable that the mechanism and the position detector for detecting the detection required position of the mechanism can be shared and the number of patterns used by the position detector can be reduced.

By the way, a conventional position detector is used on the premise that the mechanism is shared, and, for example, a high-performance VT is used.
When the R mechanism is used as the mechanism of the low function VTR, if the number of patterns to be used is reduced by using the same position detector, the detection required position of the mechanism of the low function VTR cannot be detected.

That is, assuming that the channel chD of the position detector having the pattern of the channels chA to chD as shown in FIG. 6 is not used, for example, EJE
The position P1 of CT changes from "0100" to "010", and FF
The position P11 of / REW also becomes the same from "0101" to "010", and the position P2 of L / UL STOP (loading / unloading stop) is "000".
From 0 ”to“ 000 ”, PAUSE position P10 is also“ 0 ”
It becomes the same from "001" to "000", and the coded signals at the positions which are incompatible with each other are the same. Therefore, it is possible to correspond to the position detector of the low function type VTR by simply reducing the number of used patterns. I can't.

In this case, if the number of patterns used by the position detector for detecting the mechanism position of the high-performance VTR is not reduced, it can be used as it is for the low-function VTR. At that time, the coded signal of the position detector is input. Since the input port of the control microcomputer is required as much as the case of the high-performance VTR, the mechanism of the high-performance VTR is not diverted to the low-function VTR, and the addition of the input port expansion circuit etc. Becomes necessary and expensive.

As described above, in the conventional position detector, in consideration of the reduction in the number of used patterns, there is simply a relation between the detection required position of the mechanism and the coded signal generated according to each pattern. Since the coded signal, which is the detection-required position of the mechanism, is merely output, V may be increased or decreased depending on the number of patterns to be used.
It becomes impossible to deal with the case where the number of detection required positions of the TR mechanism changes, and the mechanism and the position detector have to be dedicated according to the VTR of each function, which increases the cost.

[0010]

In order to solve the above problems, the present invention reduces the number of patterns to be selectively used among a plurality of patterns provided on a pattern member of a position detector, and When the number of detection-requiring positions in the mechanism is reduced by reducing the number of detection units of the pattern detecting means corresponding to the decrease, the coded signal of one detection-requiring position in the mechanism or the one detection-requiring position is included. The plurality of patterns are formed such that the coded signal at the detection-required position adjacent to the position is different from the coded signals at the other detection-needed positions. That is, in consideration of the decrease in the number of patterns used in the position detector, a plurality of patterns are formed by associating the detection required position of the mechanism with the coded signal generated by the plurality of patterns.

[0011]

In the mechanism, the number of patterns to be selectively used among the plurality of patterns provided on the pattern member of the position detector is reduced, and the number of detection units of the pattern detecting means is reduced in response to the reduction in the number of patterns. When the number of detection required positions is reduced, the coded signal of one detection required position in the mechanism or the coded signal of the detection required position adjacent to this position including this one detection required position,
Since a plurality of patterns are formed so as to be different from the coded signals of other detection-requiring positions, the mechanism of a device with a large number of detection-required positions is shared with a device with a small number of detection-required positions and a position detector is also shared. In this case, by reducing the number of patterns used by the position detector, it becomes possible to detect the required detection positions that are no longer needed and to accurately detect the required detection positions, which makes the position detector more versatile. improves.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a circuit configuration diagram adopting a pattern forming method in a position detector according to the present invention, FIG. 2 is an explanatory view showing one surface of a pattern disk of the position detector, and FIG. 3 is another surface of the pattern disk. Explanatory drawing, FIG. 4 (a) is a developed view in which the time axis of each pattern in FIG. 2 is expanded together, (b) is an explanatory view of output signals from each pattern, and FIG. 5 (a) is channel chD of FIG. FIG. 3B is a development view when is not used, and FIG. 6B is an explanatory diagram of output signals from each pattern.

The position detector 1 includes a disc 2 as shown in FIG.
On one surface, from the outer peripheral side to the inner peripheral side, in the order shown in FIG. 1, a conductor (black portion in the figure) that is an ON state and an insulator (white portion in the figure) that is an OFF state are provided. The four contact patterns of the channels chA to chD and the contact pattern of the common channel chG, which are alternately arranged, are formed concentrically, and as shown in FIG. 3, through a through hole (not shown) on the other surface of the disk 2. Each channel chA ~ c
A pattern disc 3 which is a pattern member formed with power feeding patterns cha to chd and chg connected to conductor portions of the patterns of hD and common channel chG, and channels chA to chD and common channel chG of this pattern disc 3. Contact each pattern chA ~
and a movable contact portion 4 which is a pattern detecting means including a plurality of contact portions 4a to 4d and 4g for detecting the on / off state of the chD, and the movable contact portion 4 is interlocked with the mechanism. It rotates (however, less than one rotation).

Then, the conductor portion of the channels chA to chD on one surface of the fixed-side pattern disk 3 is pulled up to the power supply voltage Vcc by the pull-up resistor group 5 via the feeding patterns cha to chd on the other surface and is protected. Input ports IP1 to IP of the control microcomputer 7 via the resistor group 6
4 and the common channel chG is grounded via the feeding pattern chg.

As a result, when the contacts 4a to 4d of the movable contact portion 4 are in contact with the conductor portions of the channels chA to chD, the channels chA to chD are connected to the common channel chG (grounded state) via the movable contact portion 4. Connected to the "0" level (ON state), channel ch
Each contact 4a of the movable contact unit 4 is attached to the insulator part of A to chD.
When 4d is in contact, channels chA to ch
Since D is not connected to the common channel chG (grounded state) via the movable contact portion 4 and is at the “1” level (off state), the movable contact portion 4 rotates in conjunction with the mechanism, and thus the movable contact portion A 4-bit coded signal consisting of on / off signals SA to SD depending on the position of 4, that is, the position of the mechanism is the input port IP of the control microcomputer 7.
1 to IP4, the position of the mechanism can be recognized.

Here, the portion showing the ON state and the portion showing the OFF state of each contact pattern of each channel chA to chD of the pattern disk 3 of the position detector 1 are provided according to the detection required position of the mechanism. And when the position where the mechanism requires detection decreases, each channel chA-ch
Channels chA to c which are a predetermined number of patterns in D
By hC, it is possible to detect the detection-required position of the mechanism after the reduction.

That is, the patterns of the channels chA to chD and the common channel chG of the pattern disk 3 are formed as shown in FIG. 4A, and when all the channels chA to chD are used, FIG. ), Signals SA to SD are obtained, and positions P1 to P11 are obtained.
As shown in Table 1, it is possible to detect all the mechanism positions that need to be detected as the mechanism of the high-performance VTR such as W-VHS and S-VHS by using the coded signals at 11 points in FIG. Channel chA as shown
When performing position detection using channels chA to chC without using the channel chD of
When the number of contacts of the movable contact unit 4 is reduced according to the channels chA to chC to be used, the signal S as shown in FIG.
A to SC are obtained, and by the coded signals at 10 positions other than the position P5 among the positions P1 to P11, all that need to be detected as a mechanism of a low function VTR such as a normal VTR as shown in Table 2 The mechanism position of is made detectable.

[0018]

[Table 1]

[0019]

[Table 2]

Here, the channel chD of the position detector 1
If is not used, the position P5 that can be detected when the channel chD is used is “111” from FIG. 5, and the coded signal of “111” at this time is preset as a signal between modes. , The position cannot be detected at the position P5, but as shown in Table 1, the position at which the W-VHS tape is reproduced (MP-PLA) is a mechanism position used only in the high-performance VTR.
Since Y) is assigned, there is no problem in detecting the mechanism position of the low function VTR even if it becomes undetectable.

Further, as shown in Table 2, positions P1 to P11 are set.
Positions P1 and P2, Positions P6 and P7, Positions P8 and P
9 and 9 have the same coded signal, but as shown in Table 1 and Table 2, these mechanism positions are configured to be similar, that is, positions P1 and P2 are both positions where the mechanism is unloaded. And L / U
At L STOP, positions P6 and P7 are PLAY and FWD STILL / which are the mechanism positions of the capstan forward rotation.
In SLOW, positions P8 and P9 are REV and REV STILL / SLO, which are the mechanism positions for capstan reversal.
Since they are respectively assigned to W, even if the coded signals are the same, there is no problem in detecting the mechanism position of the low function VTR. It should be noted that the same processing is performed at initialization such as when the AC power is turned on.

Further, even when the normal mechanism position is moved, it is possible to distinguish and detect even the same coded signals by detecting once that the coded signals have become "1" for all channels.

As described above, the position detector 1 reduces the number of patterns to be selectively used among the plurality of patterns (channels chA to chD) provided on the pattern disk 2 which is the pattern member, and at the same time, reduces the number of patterns. When the number of detection required positions in the mechanism is reduced by reducing the number of detection portions (movable contacts 4a to 4d) of the movable contact portion 4 which is the pattern detection means in response to the decrease in A plurality of patterns are formed such that the coded signal or the coded signal at the detection required position including the one detection required position and adjacent to this position is different from the coded signals at the other detection required positions.

By doing so, the position detector 1
Even if the number of channels used by the device is reduced, the functionally incompatible mechanism positions do not become the same coded signal. Therefore, using the mechanism of the high function type VTR with the low function type VTR, Even when the detector 1 is used and the channel chD is not used, it is possible to accurately detect the mechanism position that needs to be detected by the low function VTR.

As described above, when the mechanism of the high-performance VTR such as W-VHS and S-VHS is diverted to the low-function VTR such as the normal VTR, the conventional position detector can reduce the number of channels used. As a mechanism of the low function type VTR, a mechanism position which is wasted cannot be detected, but at the same time a necessary mechanism position cannot be detected. On the other hand, when the pattern forming method in the position detector according to the present invention is adopted, As a mechanism of the type VTR, a mechanism position which is wasted is prevented from being detected by reducing the number of channels used by the position detector, and a mechanism position which needs to be detected can be accurately detected.

As a result, it becomes possible to detect the multi-mechanism position of the high-function type VTR and the low-mechanism position of the low-function type VTR with the same position detector. It is possible to reduce the die cost. Further, since the number of channels used by the position detector is reduced in the low-function VTR, it is possible to reduce the peripheral circuit cost and the number of exclusive use of the input port of the control microcomputer.

In the above embodiment, the position detector uses the pattern disk provided with a plurality of patterns in which the conductor portion and the insulator portion are combined and the movable contact is used, but the pattern member is a slit. Alternatively, a plurality of patterns formed by the presence or absence of a reflective film are provided, and the presence or absence of a slit or reflective film in each pattern is detected by a photo sensor, a pattern formed by using a Hall element, etc.
Various ones can be used. In the above embodiment, the case where the total number of channels is 4 channels (4 patterns) and 3 channels (3 patterns) of the 4 channels are used has been described. However, the total number of channels needs to be detected. You can increase or decrease according to the number of positions,
Also, the number of unused channels can be set to two or more. Further, in the above-mentioned embodiment, the example of the rotary type position detector in which a plurality of patterns are concentrically provided has been described, but the same can be applied to a linear slide type position detector in which a plurality of patterns are provided in parallel.

[0028]

As described above, according to the present invention, of the plurality of patterns provided on the pattern member of the position detector, the number of patterns to be selectively used is reduced and the number of patterns is reduced. When the number of detection-required positions in the mechanism is reduced by reducing the number of detection sections of the pattern detection means, the coded signal of one detection-needed position in the mechanism or the one adjacent to this position including this one detection-required position is detected. Since a plurality of patterns are formed so that the coded signal of the detection position is different from the coded signal of the other detection positions required, the mechanism of the device having the many detection positions required is shared with the device having the few detection positions required, Even if the position detector is also shared, the number of patterns used by the position detector is reduced. It will be able to accurately detect the main detection position improves the versatility of the position detector, Hakare the sharing of the position detector as well as sharing mechanism, the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram adopting a pattern forming method in a position detector according to the present invention.

FIG. 2 is an explanatory view showing one surface of a pattern disk of the position detector.

FIG. 3 is an explanatory view showing the other surface of the patterned disc.

FIG. 4A is a development view in which the time axis of each pattern of FIG. 2 is expanded together, and FIG. 4B is an explanatory diagram of an output signal from each pattern.

5A is a development view when the channel chD of FIG. 4 is not used, and FIG. 5B is an explanatory view of an output signal from each pattern.

FIG. 6A is a development view in which each pattern of a conventional position detector is developed by matching the time axis, and FIG. 6B is an explanatory diagram of an output signal from each pattern.

[Explanation of symbols]

1 ... Position detector, 2 ... Disc, 3 ... Pattern disc, 4 ... Movable contact part, 7 ... Microcomputer, chA-cHD ... Channel (pattern).

Claims (1)

[Claims] 1. A pattern member in which a portion showing an on state and a portion showing an off state are alternately arranged to form one pattern, and a plurality of the one pattern are provided in parallel or concentrically. A pattern detecting means having a plurality of detecting portions for detecting the on / off states of a plurality of patterns provided on the pattern member, and the pattern member and the pattern detecting means are relatively arranged according to the position of the mechanism. A position detector that outputs a coded signal that is obtained by combining the ON / OFF states of the plurality of patterns according to a plurality of detection-required positions in the mechanism, by moving the plurality of the plurality of units provided in the pattern member. Out of the pattern
While reducing the number of patterns to be selectively used and reducing the number of detection positions in the mechanism by reducing the number of detection units of the pattern detection means in response to the reduction in the number of patterns, one of the main points in the mechanism is reduced. The coded signal of the detection position or the coded signal of the detection required position adjacent to this position including this one detection required position is
A pattern forming method in a position detector, wherein the plurality of patterns are formed so as to be different from the coded signals of other detection-required positions.