JPS62129837A - Fixed position stopping device for optical part - Google Patents

Abstract

PURPOSE:To stop an optical part accurately at a fixed position without being affected by variance among machines, etc., by measuring the time from the start of speed reduction in the middle of constant-speed backward movement to the reduction to a specific speed and setting final braking start timing on the basis of the measured time. CONSTITUTION:The optical part moves forth to a specific scanning position L1 and then begins to move back through a constant-speed backward moving means, and the optical part is accelerated up to a specific speed VR and then moves back at the specific speed VR. Then when the optical part returns to a specific position L2, the speed is reduced by an accelerating and decelerating means and the time T1 required for the reduction from the VR to VR/n is measured. Then the optical part is accelerated again by the accelerating and decelerating means up to the specific speed VR, but data on the time T1 suitable for the mechanical backward movement characteristics of the optical system which are detected at this time is used to start the speed reduction by a braking means when the optical part reaches a position L3 at specific distance from the home position LH, thereby stopping the optical part at the fixed position LH.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an optical fixed position stopping device, and more specifically, the present invention relates to an optical fixed position stopping device. This invention relates to an optical fixed position stopping device for stopping an optical part.

<Conventional technology> Conventionally, in devices that expose an original by moving an optical part, a variable speed motor is used as a drive source to achieve high-speed processing, and a return speed that does not contribute to the exposure of the original has been used. There are 12 servings of the higher version. In such devices, even if the power supply to the motor is cut off when the optical section returns to the home position (the reference position set for starting the exposure operation), the motor will overrun due to the influence of inertia. Therefore, it is necessary to cut off the power supply, brake, etc. before the home position.

Conventionally, for such a device, after turning on the power, a test scan is performed corresponding to the maximum size, and the return speed is continued to be accelerated until the specified position, and then continues to be decelerated, and the standard deceleration line is get data,
During actual operation, the device continues to accelerate until it matches the standard deceleration linear data, and then decelerates along the above linear data (see Japanese Patent Application Laid-Open No. 59-7357).
, and ■Continue accelerating the backward motion speed until a predetermined timing, then brake to achieve the specified constant speed (speed when the timing switch is activated) double motion state, and then cut off the power supply to the motor at a predetermined position. There is a method in which the predetermined timing is corrected based on preceding return operation data (see Japanese Patent Laid-Open No. 59-29238).

<Problems to be Solved by the Invention> In the above item (■), there is a problem that a memory corresponding to the deceleration reference straight line data is required, and the damper is required to stop at the correct home position. In addition to requiring a large amount of memory for control and a, II control, it also requires a mechanical braking mechanism.

be.

In addition, in the case of item (iii) above, it is difficult to set the initial braking timing, and if this setting is not appropriate, the return movement speed when the timing switch is activated will be quite high, so the stopping position will be uncertain. The problem is that it can be accurate.

In particular, although the braking timing mentioned above must be varied considerably due to variations between machines, the initial setting is almost uniform, so the return speed when the timing switch is operated is will fluctuate significantly, making it impossible to expect an accurate stop at the lateral home position.

<Object of the invention> This invention was made in view of the above problems,
It is an object of the present invention to provide an optical part fixed position stopping device that can accurately stop an optical part at a fixed position without being affected by variations between machines.

Means for Solving the Problems> In order to achieve the above object, the optical fixed position stopping device of the present invention comprises a constant speed reciprocating means, an acceleration/deceleration means, a timing means, and a timing setting means. , and control means.

The constant speed backward movement means moves the optical section back at a constant speed, and the acceleration/deceleration means moves the optical section at uI! during the constant speed backward movement. 71 L, after which the speed is decelerated, the speed is accelerated again to the constant backward movement speed, and the timing means measures the time from the start of deceleration until the speed is decelerated to a predetermined speed, and the timing setting is The means sets the final braking start timing based on the time measured by the timing means, and the control means causes the acceleration/deceleration means to perform a deceleration operation at the timing set by the timing setting means. be.

However, the deceleration and acceleration during the constant speed backward movement by the acceleration/deceleration means, the time measurement by the clocking means, and the setting of the braking start timing by the timing setting means may be performed only during the warming-up period.

<Function> Next, the function of the optical fixed position stopping device of the present invention will be explained in the first part.
This will be explained using figures. In the figure, the vertical axis represents the speed of the optical section, and the horizontal axis represents distance or time corresponding thereto.

After the optical part is moved forward to a predetermined scanning position ([1) in FIG. Do this. Next, when the optical part returns to the predetermined position ([2), the optical part is decelerated by the acceleration/deceleration means, and the time ■1 until the speed of the optical part decreases from vR to the predetermined speed vR/n is measured. Measure by means. Then, the optical section is again accelerated to the predetermined speed VR by the acceleration/deceleration means.

Through the above operations, the above-mentioned time (1) suitable for the mechanical backward movement characteristics of the optical system is detected. By using that data, the optical section is set at a distance from the home position ([■)].
When the position of L3=nVRT1/2 (n-1) is reached, the acceleration/deceleration means is operated again by the braking means to start deceleration. Through the above operations, the optical section can quickly return to the home position ([old]) without unnecessary operations such as over-braking or over-running.

<Example> Hereinafter, an example will be described in detail with reference to FIGS. 2 to 4 showing examples.

FIG. 2 is a block diagram showing the hardware of the optical fixed position stopping device of the present invention, including a control board (CB).
S/D signal, F/R signal, PLL from microcomputer (CPU) to motor controller (HC) through
This shows that a clock signal is applied and a motor driving pulse is applied from the motor controller (HC) to the DC motor (H). Further, the rotation of the DC motor (H) is monitored by the FG clock signal from the DC motor (14), and the rotation speed of the DC motor (H) can be read by calculating the pulse period of the FG clock signal. I can do it.

Moreover, FIG. 3 is a detailed diagram showing the positional relationship around the optical part, (2) is the optical part, (3) is the light emitter, (4) is the main reflector, (5) is the sub-reflector, ( 6) shows a flat reflecting mirror. Two sensors (81) and (32) are attached to predetermined positions below the contact glass (1), and the first
The sensor (Sl) detects the home position (LH), and the second sensor (S2) as a detection means moves a predetermined distance l1lii from the home position (LH) to the exposure end position.
They are respectively provided so as to detect the set position (L2) that has changed. However, the above prescribed position i2! (L2) is sufficient to reach a stable backward movement speed vR after the optical part (2) starts to move backward from the scan end position H (11) of the test scan toward the home position (Ll+). The setting is such that the travel distance is secured.

As each of the above-mentioned sensors (81) and (32), a photoelectric switch, a reed switch, etc. can be used, and the optical part (2
) is selectively driven by an optical path blocking plate, a light reflecting plate, a magnet, etc. as a detected part (7) attached to a predetermined position of the sensor. Also, in the figure ([3) is the optical part (2
) shows the position where braking starts.

The operation of the optical fixed position stopping device having the above configuration will be explained with reference to the flowchart shown in FIG.

After the power is turned on, it is determined in step (2) whether or not it is in a warm-up state, and if so, it is maintained until the test scan mode is entered in step (2). When the test scan mode is entered, scanning is performed without lighting the light emitting body (3), and after waiting until the return movement is started in step The motor controller (HC) supplies a forward rotation drive signal to the DC motor (4) to apply braking until the optical section passes over the sensor (S2), and then the microcomputer (HC) applies a brake. The time of the timer provided in the CPU is cleared and the time counting operation is started. Wait until the speed of the optical section becomes 1/2 of VR in step J3, and then read the time measured by the timer in step 3. and,
The time (2T1) to start braking the optical part in step ■ and its position (distance in Fig. 1!11L3=VRT
l, n-2). In step (2), the optical section is driven in the reverse direction, and the backward movement speed of the motor (H) is again set to vR&-. In step [stock], the optical part is held until it reaches the above-mentioned braking start position (distance tli (L3) in Fig. 1), and in step ■, braking is started again by normal rotation drive, and at the same time, the timer starts timing operation. do. Then, in step @, the optical unit is stopped by waiting until the time measured by the timer reaches 2T1 and applying a stop signal to the DC motor (H) in step @.

Through the above discrimination process, using the test scan time,
By actually measuring the braking response characteristics of the optical part, it is possible to set an appropriate braking start timing for each machine.

In addition, if the warm-up state is not reached in step ① above, the operations in step [phase] and below are performed without performing the operations in steps ② to ②, and normal rotation braking is performed at the timing set during the test scan. ,
Stopping at an accurate home position can be achieved.

Note that the above series of operations does not necessarily need to be performed during a test scan, and the entire operation of steps ① to O may be performed during normal copy exposure, but deceleration and re-acceleration may be performed during the backward movement. Because it is necessary, it takes more time to copy.

<Effects of the Invention> As described above, according to the present invention, it is possible to prevent overrun during the backward movement of the optical part scanning and to accurately stop the optical part at the home position.

[Brief explanation of drawings]

Figure 1 is a graph showing the speed change of the optical part during a test scan, Figure 2 is a block diagram of the optical part fixed position stop device, Figure 3 is a diagram showing the positional relationship of the optical part, etc., and Figure 4 is flowchart. (2)...optical section,

Claims (1)

[Claims] 1. By moving the optical part, the original In devices that perform exposure of Constant-speed double-acting means for backward-moving at a constant speed; During the return movement, the optical part is braked and reduced. After increasing the speed, accelerate it again to the constant backward motion speed. Acceleration/deceleration means to accelerate and a predetermined speed from the start of deceleration Measure the time it takes to decelerate to the speed of time measurement means and time measured by the time measurement means Final braking start timing based on A timing setting means for setting the tag and a timing setting means for setting the tag. The timing set by the timing setting means deceleration operation using acceleration/deceleration means. and a control means for causing the Optical fixed position stop device. 2. In the middle of constant speed backward movement by acceleration/deceleration means deceleration and acceleration, time measured by timekeeping means Control by measurement and timing setting means The setting of the warm start timing is Things that only take place during the training period According to claim 1 above, Optical fixed position stop device.