JPS61223610A - Servo recorder - Google Patents

Abstract

PURPOSE:To prevent the damage due to shake-off of a carriage by fixing the input applied to a servo system to an upper limit value in case of over scale and fixing it to a lower limit value in case of under scale. CONSTITUTION:A measured signal X impressed to an input terminal 31 is amplified by a preamplifier 32 and is read into a microprocessor muP 35 through an A/D converter 33 and is subjected to the arithmetic processing. The muP 35 compares an output X1 of a D/A converter 39 with the lower limit value and the upper limit value of the effective span of the carriage. If the value of the input X falls and the output X1 is smaller than the lower limit value, the muP 35 fixes the output X1 of the converter 39, namely, the input applied to the servo system to the lower limit value independently of the input. If the input X is increased and its value will exceed the upper limit value, the muP 35 fixes the output X1 to the upper limit value. As the result, the carriage is stopped in a position before striking against a mechanical stopper.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a servo recorder equipped with means for protecting the carriage from swinging out.

[Conventional technology]

A conventional example of a servo recorder equipped with this type of protection means is shown in the fourth example.
As shown in the figure. In the figure, 10 is a servo recording unit, the deviation between the measured human force A position signal generating circuit is connected to the rotating shaft of the motor 13 and generates a signal corresponding to the position of a carriage on which a pen or a dot is mounted.The signal obtained by this circuit is fed back to the deviation amplifier 11 as a position signal F. Ru. This constitutes a servo system, and the value of the measured human force X is recorded by a pen or dotting mechanism mounted on the carriage.

Reference numeral 20 denotes a protection circuit provided in the servo recording section 10 when the carriage swings out. Comparators 21 and 22 in the protection circuit 20 compare the position feedback signal F with a voltage es corresponding to 100% of the effective recording span and a voltage ez corresponding to 0%, and detect over (under) scale based on the comparison result. This detection signal is applied to the power amplifier 12 in the servo recording section 10 via transistors 23 and 24, and reduces the power supplied to the servo motor 13.

Thereafter, the carriage contacts the stopper, thereby preventing the carriage from swinging out.

A servo recorder equipped with a shake-out protection means configured in this way has been used in the past, but [B] When the input is over (under) scaled, the servo motor 13
Even if the power is lowered, the carriage will hit the stopper, so there is a risk that the carriage will be damaged by the '4i0.

Even if the power of the servo motor 13 is lowered, if the input over (under) scale continues for a long time, the motor will overheat and the thread will wear out.

[Problem that the invention seeks to solve]

SUMMARY OF THE INVENTION An object of the present invention is to provide a servo recorder equipped with a means for preventing the carriage from swinging out, which solves the above-mentioned problem (a) and the opening problem.

[Means for solving problems]

In order to achieve the above object, the present invention sets the upper and lower limits of the effective recording span, and fixes the input to the servo system at the upper limit when overscaling based on the judgment of the microprocessor, and When , it is fixed at the lower limit value. Examples will be described below.

〔Example〕

FIG. 1 is a circuit diagram of an embodiment of a servo recorder equipped with a protection means according to the present invention. In FIG. 1, 31 is a terminal to which measurement input signal JX is applied, and this input terminal is connected to the analog/digital converter 1'A/D via a preamplifier 32.
converter) 33. 34 is a bus, 35 is a microprocessor (μP), 36 is a memory, 37 is an interface for the display section 38, and 39 is a digital/analog converter (D/A converter). ^/D converter 33. Memory 36. Interface 37 and D/A converter 39 are each connected to bus 34 controlled by μP 35.

Reference numeral 10 denotes a servo recording section, which includes a servo amplifier 11 that amplifies the deviation between the output x 1 of the D/A converter 39 corresponding to the measurement input X and the position feedback signal F, a servo motor 13 that rotates with the output of this servo amplifier, and It consists of a position signal generation circuit 14 that generates a signal according to the position of the carriage connected to the rotating shaft of the servo motor 13, and the signal obtained from this generation circuit is sent to the servo amplifier 11 as a position feedback signal F.
The servo system is configured by this.

[A] in Fig. 2 shows each span of the recorder in Fig. 1 and the movable range of the carriage. A: Recording span (0 to 100%) B: Effective recording span (-1 to 0 to 100 to 101%)C
: Movable range of carriage D: Represents measurable full span. bl is the lower limit value of the effective recording span B, b2 is the upper limit value, and these mbl and b2 are each set as digital values in the memory 36. Note that in the movable range C of the carriage, cl represents the mechanical stopper position on the 0% side, and C2 represents the mechanical stopper position on the 100% side. FIG. 2) is a diagram showing the signal relationship of the servo system in the recorder of FIG. The operation of the servo recorder shown in FIG. 1 having the functions shown in FIG.

The measurement signal X applied to the input terminal 31 is sent to the preamplifier 32.
After being amplified (normalized) by the A/D converter 33
is converted into a digital signal. This signal is read by the μP 35 and subjected to arithmetic processing such as linearization or scaling. This arithmetic processed signal is converted into signals 2a for display and recording, and one of the signals is applied to the display interface 37 and its value is displayed on the display section 38. The other signal is applied to D/A converter 39. ' The D/A converter 39 outputs an analog signal represented by xl.

Here, the μP 35 compares the output of the D/A converter 39 with the lower limit value b1 and upper limit value mb2 in the effective span B, respectively. In this case, the relationship between Xl, bl, and b2 is bl(
xi<b2. That is, if the input X1 applied to the servo system is within the range B, xl will vary according to the input amount X.

This signal X1 is applied to the servo motor 13 via the servo amplifier 11 and compared with the signal F generated by the position signal generating circuit 14. In this way, if the measurement signal X is within the range of the effective recording span B, the pen or dotting mechanism mounted on the carriage performs recording according to the input amount.

Here, when the value of input X decreases and Xl becomes smaller than the lower limit value 131 of effective recording span B (underscale),
Regardless of the input, μP 35 sends the output X1. of this D/A converter to D/A converter 39. That is, the input applied to the servo system is fixed at the lower limit value b1. Similarly, when the input X increases and its value attempts to exceed the upper limit ib2 (overscale), the μP 35 fixes the output X1 of this D/A converter to the upper limit b2 to the D/A converter 39. . D
/A converter 39 output X1. When is fixed at points bl and b2, the servo system 10 is balanced at points bl and b2, respectively, as shown in Figure 2. As a result, the carriage is
It stops at a position before hitting the mechanical stoppers at C1 and C2 shown in Figure [A].

In addition, if the servo system is a digital servo, the D/A
A transducer is not required and an encoder may be used as the position feedback element.

〔Effect of the invention〕

In a servo recorder having such a protection means for protecting the carriage, [a] Even if the carriage is over (under) scaled, the carriage does not hit the stopper, so there is no damage to the carriage.

) Even if over (under) scale input is applied, the balance of the servo system is maintained, resulting in less power consumption and less heat generation.

Q) Since the upper and lower limit values are set digitally, there is no need to adjust the comparator threshold, and even if the amount of over (under) scale in the carriage movable range is small, the limits can be set reliably.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram showing an embodiment of the servo recorder according to the present invention, Fig. 2 is a diagram for explaining the functions of the recorder shown in Fig. 1, and Fig. 3 is a diagram showing the function of the recorder shown in Fig. 1. A flowchart for explaining the operation, FIG. 4 is a circuit diagram of a conventional servo recorder. 10... Servo recording unit, 35... Microprocessor, 13... Servo motor.

Claims (1)

[Claims] In a servo recorder that records a measurement input converted into a digital signal by adding it to a servo system under the control of a microprocessor, the upper and lower limits of the effective recording span are set. Based on the judgment of the microprocessor, the input applied to the servo system is fixed at the upper limit value when the scale is overscale, and is fixed at the lower limit value when the input is underscale.