JP3343838B2 - Mechanical position control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical position control device, and more particularly to a mechanical position control device of a device designed to change a mechanical position according to a rotation angle of a master cam.

[0002]

2. Description of the Related Art As a typical example of a device generally used in which a mechanical position changes according to a rotation angle of a master cam,
There is a video tape recorder (hereinafter, VTR). Less than,
The prior art will be described using a mechanical position control portion of a VTR as an example.

FIG. 7 is a block diagram for explaining an example of the prior art. As a method for obtaining information for controlling a mechanical position, a method of changing information according to the rotation angle of a master cam is described.
This is an example (prior art example 1) in which mechanical position detection is intended to be realized by a system signal. In the figure, reference numeral 31 denotes a key input unit,
32 is a system control unit, and 33 is a motor driver.
In the conventional example 1, the information for controlling the mechanical position is obtained by turning the mechanical position switches SW3a and 3b "ON" and "OFF" according to the rotation angle of the master cam (not shown). The signal S31 of the switch SW3a and the signal S32 of the mechanical position switch SW3b are provided to the system control unit 32. The system controller 32 determines (recognizes) the mechanical position based on the information of the signals S31 and S32, and controls the tape control signal S via the motor driver 33 so that the tape is not loosened or overstretched.
33 and a master cam control signal S34.

FIG. 8 is a diagram showing the relationship between the master cam rotation angle and the mechanical position in the example shown in FIG.
Are the mechanical positions, for example, mechanical position A is the mechanical position at the time of ejection.

FIG. 9 is a block diagram for explaining another example of the prior art. As a method of obtaining information for controlling the mechanical position, a method of obtaining one system of signals which changes according to the rotation angle of the master cam is used. This is an example (prior art example 2) in the case of realizing mechanical position detection. In the figure, reference numeral 41 denotes a key input unit, 42 denotes a system control unit, and 43 denotes a motor driver. In the second conventional example, the information for controlling the mechanical position is obtained by turning the mechanical position switches SW4a to 4d "ON" and "OFF" in accordance with the rotation angle of the master cam. System controller 42 in form
Given to. In the system controller 42, this signal S4
The tape control signal S42 and the master cam control signal S43 are controlled via the motor driver 43 so that the mechanical position is determined (recognized) based on the information 1 and the tape is not loosened or overstretched. . In the case of this example, if there is a section in which a plurality of switches SW are simultaneously turned “ON”, the types of input voltage levels increase, and there is a margin for setting a voltage in a discrimination effective range for discriminating a certain voltage level. In order to prevent a plurality of switches SW from being turned “ON” even if a mounting error of the switches SW is included, the interval of a given switch SW is “ON” and all other switches SW are “OFF”. It is provided so that it becomes. FIG. 10 is a diagram showing the relationship between the master cam rotation angle and the mechanical position in the example shown in FIG.

However, in the case of Conventional Example 1, when the mechanical position is determined in the initial state (at startup), a section where the mechanical absolute position can be distinguished (a section where the mechanical position can be determined).
Are only two sections (section * 1 in FIG. 8) in which the mechanical position switch SW3a is “ON”.
When the rotation angle of the master cam is not in the section where the mechanical absolute position can be distinguished, it is necessary to rotate the master cam to the section where the absolute position can be distinguished. At this time, since the mechanical position has not been determined, the VTR takes up the tape under the condition of the greatest common denominator so that the tape mounted on the VTR moves from all positions so that tape damage is minimized. The master cam must be moved while performing the above operations. That is, unnecessary control is performed for a certain mechanical position, and the control is wasted. Furthermore, since the mechanical position is controlled only by the signal, a disturbance may occur between the actual mechanical position during operation and the mechanical position recognized by the control side due to disturbance noise (abnormal state). However, since the absolute position cannot be distinguished depending on the section, detection of an abnormal state is delayed, and tape damage may occur during operation during the abnormal state.

Further, in the case of the conventional example 2, since any mechanical absolute position can be distinguished in a section where any one of the switches SW is "ON", the control for determining the mechanical position is performed as follows.
Although it is relatively simple as compared with the conventional example 1, in the section where all the switches SW are "OFF", the absolute position cannot be distinguished, so that the master cam is moved to a position where the absolute position can be distinguished. The process for performing the same is necessary as in the first conventional example. Furthermore, since the number of components increases in accordance with the number of mechanical positions that need to be distinguished, it is necessary to correspond a substrate pattern or the like to the number of mechanical positions in advance in order to increase the mechanical positions. It is disadvantageous in terms of standardization, high-density mounting, and cost.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to make it possible to roughly distinguish mechanical positions at all master cam rotation angles. In addition, it prevents malfunctions due to disturbance noise, has the same circuit configuration irrespective of the number of required mechanical positions, and has a mechanism that can respond even when the rotation angle of the master cam and the mechanical position are changed. It is an object to provide a position control device.

[0009]

According to a first aspect of the present invention, there is provided a mechanical position control device of a device designed so that a mechanical position changes according to a rotation angle of a master cam. Voltage generating means for generating a voltage change according to the rotation angle of the master cam; signal means for generating an intermittent signal corresponding to a discrete mechanical position which is accurately set; Voltage comparison / determination means for determining the approximate mechanical position information for controlling the mechanical position by comparing the effective range voltage set by the effective range information for each of the positions, and detecting the intermittent signal generated by the signal means Signal determining means for determining the validity of the intermittent signal generated by the signal means based on the voltage of the voltage generating means and the effective range voltage information generated when The mechanical position can be detected based on the voltage change and the intermittent signal generated by the signal means, so that the mechanical position can be determined at all mechanical positions without rotating the master cam. In addition, since the above-mentioned voltage change is also taken in as information, it is resistant to disturbance noise during operation.
Further, the circuit configuration is the same regardless of the number of required mechanical positions.

According to a second aspect of the present invention, there is provided a mechanical position control device for an apparatus designed to change a mechanical position in accordance with a rotational angle of a master cam. Voltage generating means for generating a voltage change in response to the signal, signal means for generating an intermittent signal corresponding to a discrete mechanical position which is accurately set, and voltage generating means for detecting a signal generated by the signal means. Effective range calculating means for calculating the value of the effective range voltage of each mechanical position with respect to the intermittent signal generated by the signal means based on the voltage value of the means, and effective means for storing the calculated effective range voltage. A range storage unit, a voltage comparison determination unit that determines general mechanical position information for controlling a mechanical position by comparing a voltage of the voltage generation unit with the effective range voltage, and the signal unit. A signal judging means for judging the validity of the intermittent signal generated by the signal means based on the voltage of the voltage generating means generated when the generated intermittent signal is detected and the effective range voltage information; And the intermittent signal generated by the signal means so that the mechanical position can be detected.In all the mechanical positions, the approximate mechanical position can be determined without rotating the master cam. Since the voltage change is also taken in as information, it is resistant to disturbance noise during operation. Furthermore, regardless of the number of required mechanical positions, the same circuit configuration is used, and the effective range of the voltage for the signal corresponding to the rotation angle can be calculated. The correspondence between the rotation angle of the master cam and the mechanical position Is used without changing the mechanical position control device.

According to a third aspect of the present invention, the voltage changing means according to the rotation angle of the master cam outputs a voltage proportional to the rotation angle by using a slip resistor, and applies different voltages to all the rotation angles. It is made possible.

[0012]

FIG. 1 is a block diagram for explaining an embodiment of the present invention, which will be described below with reference to FIG. The mechanical position is determined according to the rotation angle of the master cam, and the rotation angle of the master cam can be changed by a master cam control motor (motor driver 13). According to the present invention, the information for controlling the mechanical position is obtained by intermittently turning on / off the mechanical position switch SW1 corresponding to the discrete mechanical position that is accurately set. A mechanical position resistance signal S1 obtained by a signal S11 and a voltage change of a mechanical position resistance R1 whose resistance value changes according to the rotation angle of the master cam.
2 are formed. Mechanical position resistance signal discriminator 15
Is provided in advance with effective range information of a mechanical position switch SW edge (when the mechanical position switch SW is turned ON / OFF) corresponding to each of the mechanical positions.
The comparison voltage S13 (Al, Ah, Bl, Bh, ..., Gl,
Gh), and is output as appropriate. The mechanical position resistance signal discriminating unit 15 compares the comparison voltage S13 with the mechanical position resistance signal S12 and compares the output of the comparator 14 with the comparison result S14.
Is input, it is determined which of the general mechanical position categories the current mechanical position belongs to, and the result of the determination is output to the system control unit 12 as general mechanical position information S15. In the system control unit 12,
The mechanical position information S15 and the mechanical position switch SW signal S11 are input, and the mechanical position control is performed by controlling the master cam control signal S16 based on these. FIG. 2 is a diagram showing the relationship between the master cam rotation angle and the mechanical position in FIG.

Next, control by the system control unit 12 in the initial state will be described. First, in the initial state, the mechanical position is indefinite (undetermined), and it is necessary to immediately rotate the master cam so as to move to the correct mechanical control position (target mechanical position, mechanical position in the initial state, etc.). The rotation of the master cam without any control of the undetermined mechanical position may cause tape damage to the tape mounted in the VTR, so that the moving direction, the tape state, and the like are restricted. There are cases. Therefore,
In the present invention, in the initial state, the approximate mechanical position information S15 can be obtained, and based on the information S15, the master cam control signal S16 and the tape control signal S17 are controlled according to the mechanical position, and the moving direction, the tape state, Also, tape damage can be prevented by determining the target mechanical position and starting mechanical movement.

FIG. 3 is a flowchart of a mechanical movement process to the target mechanical position in the embodiment of FIG.
Hereinafter, description will be made with reference to FIG. When the target mechanical position is input by the key input unit 11, the system control unit 12 first requests the master cam control signal S16 to rotate the master cam in the direction of the target mechanical position (step S101). . Next, the mechanical position switch S
The change edge of W1 is set to the S11 detection state (step S10).
2) When the change edge S11 is detected, a mechanical position effective range check CK (Step S103) is performed. This check CK is performed when the mechanical position resistance signal S14 generated at the time of detecting the change edge S11 is out of the effective mechanical position range for all the mechanical positions.
11 is determined to be disturbance noise, and the next change edge S1 is determined.
1 and, if any one of the mechanical positions indicates that it is within the effective range of the mechanical position, the change edge S11
Is determined to be valid, and the next step (step S10
Go to 4). Next, the mechanical position resistance signal S14 generated at the detected change edge is compared with the effective range information of the target mechanical position (step S104). If the target mechanical position is not reached, the SW edge S11 detection state (step S104) is again performed. S102), and if it is the target mechanical position, it is determined that the movement has been completed and the master cam control signal S16
Then, a stop request is made (step S105), and the mechanical movement processing is completed.

Thus, even when disturbance noise enters the signal S11 of the mechanical position switch SW1, if the disturbance noise is out of the effective range of the mechanical position, the disturbance noise is ignored and there is no influence. If there is, the disturbance noise will be recognized as a correct signal, but the mechanical position at the time of the disturbance noise is only slightly deviated from the correct mechanical position and is close to the correct mechanical position,
Tape damage will be minimized. Further, even when the mechanical position is moved thereafter, in the case of the flowchart in FIG. 3, the change edge S11 of the mechanical position switch SW1 is ignored until the mechanical position is within the target mechanical position section. If there is no disturbance noise within the mechanical position effective range of the mechanical position, the mechanical misalignment will be naturally repaired, and even if mechanical misalignment occurs, there is no hindrance to subsequent mechanical position movement, and mechanical misalignment is repaired. No control is required.

FIG. 4 is a block diagram for explaining another embodiment of the present invention. The block diagram is based on the block diagram shown in FIG. 1 and has a structure in which a mechanical position effective range information storage unit 26 is added. Have been. In the embodiment shown in FIG.
Although the mechanical position effective range information is set in the mechanical position resistance discriminating unit 15, the mechanical position effective range information is independent of the mechanical position resistance signal discriminating unit 25 in this embodiment shown in FIG. The mechanism position effective range information can be changed when desired. The storage unit 26 uses a storage device that does not require a power backup. The mechanical position resistance signal discriminating unit 25 normally uses the comparison voltage S21 based on the mechanical position effective range information S20 stored in the storage unit 26.
Is output, and the same control as in the embodiment of FIG. 1 is performed. However, when the system control unit 22 receives a voltage comparison request S22 including comparison voltage information, the mechanical position resistance signal discrimination is performed. The unit 25 outputs the comparison voltage S21 based on the comparison voltage information to the comparator 24, outputs the result from the comparator 24 to the system control unit 22 instead of the general mechanical position information S23, and accurately outputs the result. Change edge S of switch SW2 corresponding to the set discrete mechanical position
The mechanical position effective range for 26 is reset.

FIG. 5 is a flowchart for explaining the mechanical position effective range resetting operation when there is voltage comparison information including the comparison voltage information, which will be described below with reference to FIG. Mechanical position reset request S2 from key input unit 21
When there is a request, the system control unit 22 first outputs a rotation request in the rotation angle decreasing direction by the master cam control signal S25, and then sends a voltage comparison request S22 including reference voltage information to the mechanical position resistance signal determination unit 25. (Step S2)
01). Next, the mechanical position resistance signal discriminating unit 25 determines the mechanical position resistance signal S27 of the mechanical position resistance R2 with respect to the reference voltage according to the voltage comparison request S22 from the system control unit 22.
Is output to the system control unit 22, and the system control unit 22 can recognize the completion of the mechanical movement to the reference position based on the comparison result. If the mechanical movement is completed in the mechanical movement check CK to the reference position (step S202), the master cam control signal S2
5 is stopped (step S203), the rotation request is switched to the rotation angle increasing direction (step S204). Next, in the system control unit 22, the mechanical position switch SW
2 change edge S26 detection waiting state (step S20)
5), when the change edge S26 is detected, the master cam control signal S25 is set to the stop state (step S206), and based on the result of comparison by the comparator 24 input through the mechanical position resistance signal determination unit 25, the position at this position is determined. The comparison between the mechanical position resistance signal S27 and the comparison voltage S21 is performed (step S207). The value of the comparison voltage S21 at this time is compared with the value set in the previous comparison (the reference voltage when the first change edge S26 is detected after the movement to the reference position). As a result, if the comparison voltage S21 is lower than the comparison voltage S21, the comparison voltage S21 is increased by one preset step (step S208), and then again.
Repeat the comparison.

When the comparison result becomes a positive value (comparison voltage S21 or more) by this repetition, a change edge X obtained by detecting a value obtained by subtracting a preset variation 1 from the comparison voltage value at that time is detected. Lower limit voltage information X of the effective range for
and the amount of variation h in the value of the comparison voltage at that time.
Is stored (re-set) in the mechanical position effective range information storage unit 26 as the mechanical position effective range as upper limit voltage information Xh of the effective range (S28), and the change edge of the mechanical position switch SW2 whose effective range is reset is changed. A counter for counting the number is counted up (step S2).
09). Next, the counter value is compared with a preset number of change edges of the mechanical position switch SW2 (step S210). If the value of this counter is less than the preset number of mechanical position switch SW edges,
In order to find the next change edge S26, the processing from the master cam rotation request (step S204) is performed again. If the change edge number is equal to or more than the change edge number of the mechanical position switch SW2, the mechanical position effective range reset operation ends. . Thereafter, by using the information stored in the mechanical position effective range information storage unit 26 as the mechanical position effective range information, the mechanical position moving operation in the initial state is performed in the same process as the embodiment shown in FIG. Then, the processing is performed. FIG.
FIG. 4 is a diagram showing the relationship between the master cam rotation angle and mechanical position information and the like according to the embodiment shown in FIG. .

[0019]

【The invention's effect】

Effect common to all claims: In the initial state, the approximate mechanical position can be determined without moving the master cam with respect to the entire rotation angle of the master cam, so that optimal control for the mechanical position can be performed. This eliminates the need for useless control (redundant operation to correspond to all mechanical positions). Furthermore, since the effective range voltage is provided at the signal change edge of the switch SW corresponding to the discrete mechanical position that is accurately set, a signal check is performed. Is no longer accepted. Furthermore, even if the number of required mechanical positions increases or decreases, it is possible to cope with the same circuit configuration without changing the board pattern, etc., just by changing the control in the system control unit, and the common use of the board between different devices can be achieved. And cost reduction can be realized.

According to the second aspect of the present invention, the preset effective range for the signal change edge of the mechanical position switch SW can be changed, so that the resistance voltage level is generated for each device due to the variation of the resistance value or the mounting error of the switch SW. Without providing a redundant part for the variation, the effective range for the change edge can be narrowed and accurate, the noise range can be further strengthened, and the effective range can be narrowed. Among them, many setting ranges are provided, and it is possible to cope with a device having a large number of necessary mechanical positions. Furthermore, if the number of necessary mechanical positions and the control at the mechanical position remain the same, and if the rotation of the master cam with respect to the mechanical position is changed, if the front-back relationship of the mechanical position does not change,
Since the mechanical position with respect to the rotation angle of the master cam can be reset, it can be used without changing the control of the system control unit.

According to the third aspect of the present invention, since the resistance value changes in accordance with the rotation angle, it can be achieved with a simple configuration so that different output voltages can be obtained for all rotation angles.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a master cam rotation angle and a mechanical position in FIG.

FIG. 3 is a flowchart showing a movement process to a target mechanical position in FIG. 1;

FIG. 4 is a block diagram for explaining another embodiment of the present invention.

FIG. 5 is a flowchart showing the operation of resetting the mechanical position effective range in FIG. 4;

FIG. 6 is a diagram showing a relationship between a master cam rotation angle and a mechanical position in FIG.

FIG. 7 is a block diagram for explaining an example of the related art.

8 is a diagram showing a relationship between a master cam rotation angle and a mechanical position in FIG.

FIG. 9 is a block diagram for explaining another example of the related art.

10 is a diagram showing a relationship between a master cam rotation angle and a mechanical position in FIG.

[Explanation of symbols]

11: Key input unit, 12: System control unit, 13: Motor driver, 14: Comparator, 15: Mechanical position resistance signal discrimination unit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁷ , DB name) G11B 15/10 G01B 7/00 G05D 3/00

Claims (3)

(57) [Claims] In a mechanical position control device of a device designed to change a mechanical position according to a rotation angle of a master cam, a voltage change according to a rotation angle of the master cam is shown to indicate a rough mechanical position. Voltage generating means, signal means for generating an intermittent signal corresponding to a discrete mechanical position which is accurately set, and voltage set by the voltage of the voltage generating means and effective range information for each of the mechanical positions. A voltage comparison / determination unit that determines general mechanical position information for controlling a mechanical position by comparing the voltage with an effective range voltage; and a voltage generation unit that is generated when an intermittent signal generated by the signal unit is detected. A mechanical position control device, comprising: signal determination means for determining the validity of an intermittent signal generated by said signal means based on a voltage and said effective range voltage information. 2. A mechanical position control device of a device designed to change a mechanical position according to a rotation angle of a master cam, wherein a voltage change according to the rotation angle of the master cam is shown to indicate a rough mechanical position. Voltage generating means for generating, a signal means for generating an intermittent signal corresponding to a discrete mechanical position which is accurately set, and a voltage generation means for detecting a signal generated by the signal means. Based on the value,
Effective range calculating means for calculating the value of the effective range voltage of each mechanical position with respect to the intermittent signal generated by the signal means, effective range storage means for storing the calculated effective range voltage, and voltage of the voltage generating means Voltage comparison / determination means for determining general mechanical position information for controlling the mechanical position by comparing the voltage with the effective range voltage; and the voltage generation generated when the intermittent signal generated by the signal means is detected. A mechanical position control device, comprising: signal determination means for determining the validity of the intermittent signal generated by the signal means based on the voltage of the means and the effective range voltage information. 3. The mechanical position control device according to claim 1, wherein the voltage changing means according to the rotation angle of the master cam uses a slip resistor.