JPS6126885Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to automatic correction of expansion and contraction of recording paper of a recorder.

One of the problems with recorders that record on recording paper in response to measurement input signals is expansion and contraction of the recording paper. As shown in Figure 1, there is a predetermined relationship between humidity and the elongation of recording paper, and when the humidity changes from 0 to 90%, the recording paper expands and contracts by a maximum of about 2% relative to the entire scale width. conduct. Normally, recorders are designed to obtain correct recording results when the recording paper does not expand or contract, so if the recording paper expands or contracts, a corresponding recording error will occur. For this reason, in order to allocate errors, printing of scales on recording paper is controlled so that it is performed at a humidity of 65%.

In view of the above, the purpose of this invention is to detect the humidity around the recording paper by taking advantage of the fact that there is a predetermined relationship between humidity and the expansion and contraction of the recording paper width, and to record according to the expansion and contraction of the recording paper width. To provide a recorder that automatically corrects span and reduces recording errors.

An embodiment of this invention will be described in detail below with reference to the drawings. FIG. 2a shows a basic block diagram of the self-balancing recorder. 1 is orthogonal transformer, 2
is an amplifier, 3 is a servo motor, 4 is a sliding resistor, 5
1 is a recording mechanism, 6 is a humidity detector, and 7 is a correction circuit. The deviation input of the input signal amount θi and the feedback voltage due to the sliding resistor 4, which will be described later, is converted into alternating current by the orthogonal converter 1, amplified by the amplifier 2, and then applied to the servo motor 3.
to drive. The brush of the sliding resistor 4 moves in conjunction with the servo motor 3, and a feedback voltage depending on the position of the brush is added to the input signal θi. Balance is maintained at a position where the deviation between the input signal θi and the feedback voltage is zero.
At this position, the recording mechanism 5 performs a recording operation. The relationship between the input signal amount θi and the output displacement amount θo is as follows:
The gains of Bomotor 3 and sliding resistance 4 are respectively
If K ₁ , K ₂ , K ₃ , and K ₄ are used, it is given by the following formula.

The gain K ₃ of the servo motor 3 is considered to be infinite because it continues to rotate as long as voltage is applied to the servo motor 3, and θo=θi/K ₄ (2). Therefore, the humidity around the recording paper is detected by the humidity detector 6, which is made up of a humidity sensing element, for example, and the correction circuit 7 uses this detection signal to correct the relationship between the humidity and the expansion and contraction of the recording paper. The feedback gain K ₄ due to the sliding resistance 4 in equation (2) is changed. For example, when the humidity is high, the recording paper stretches, so _K4 can be changed to account for this stretching, and θo can finally be increased.

FIG. 2b is a principle block diagram of a self-balancing recorder including a preamplifier 8 without a quadrature transformer. In this case, the input signal amount θi and the output displacement amount θo
The relationship finally becomes θo=K ₀ /K ₄ θi (3). Note that K ₀ is the gain of the preamplifier 8. Therefore, the humidity is detected by the humidity detector 6, and the above-mentioned gain ratio is adjusted based on this detection signal via the correction circuit 7.
By changing K ₀ /K ₄ , the recording span can be changed in accordance with the expansion and contraction of the recording paper. In this case, K ₄
Only one of K0 and _K0 may be changed.

FIG. 3 shows a more specific embodiment of FIG. 2a, using a potentiometer circuit 4' including a sliding resistor as the measuring circuit. For Rp, the brush is servo motor 3
Rs is the shunt resistance of this sliding resistor, Rvs is the variable resistor for span adjustment, and Rl is the resistor for current regulation.These resistors form one side of the potentiometer circuit, and The other side is formed by resistors Rz and Ro, variable resistor Rvz for zero point adjustment, and resistor _R2 for current regulation. If the constant current flowing to each side obtained by dividing the constant voltage ES by the combined resistance of each side of the potentiometer circuit is I, then the position of the brush of the sliding resistance Rp in the equilibrium state is θ (O < θ < I ) is given by the following equation, which is equal to the input voltage Ei.

Then, Ei=Aθ−B ∴θ=1/AEi+B/A ……(4). Therefore, the humidity is detected by the humidity detector 6, and the detected signal is transmitted through the correction circuit 7 to (4)
By changing the value of A in the equation, that is, the values of I, Rs, Rvs, etc., the brush position θ may be changed to correct the recording span according to the expansion and contraction of the recording paper. Alternatively, you can directly use a humidity-sensitive element whose resistance value changes depending on humidity.
You can also use it instead of RVs. Then, a changeover switch is installed between the humidity sensing element (humidity detector) and the measurement circuit to prevent the detection signal of the humidity sensing element from being applied to the measurement circuit, and this changeover switch measures the output of the humidity sensing element. By not giving it to the circuit,
It is possible to read the indicated value using a fixed scale plate without performing a recording span correction operation.

As described above, this invention consists of a humidity sensing element that detects the humidity around the recording paper, a measurement circuit that corrects the recording span based on the detection signal of the humidity sensing element, and a measurement circuit that uses the detection signal of the humidity sensing element to correct the recording span. This recorder is equipped with a changeover switch that prevents the humidity from being applied to the recording paper, and uses the fact that there is a certain relationship between humidity and the expansion and contraction of the recording paper to correct the recording span according to the expansion and contraction of the recording paper. be.

Therefore, it is possible to prevent recording errors in environments of high humidity and low humidity, as in the prior art. In addition, automatic correction is performed electrically, so no human effort is required〓〓〓〓
It is. In particular, if humidity is directly converted into an electrical signal using a humidity sensing element, etc., and correction is performed,
Further miniaturization becomes possible. In addition, if you want to know the true indicated value, change the changeover switch so that the detection signal of the humidity sensing element is not applied to the measurement circuit, and use the fixed scale plate to correct the recording span.
All you have to do is read the indicated value.

[Brief explanation of the drawing]

Figure 1 is a diagram of the relationship between humidity and elongation of recording paper related to this invention, Figures 2a and b are block diagrams showing an example in which this invention is applied to an automatic balancing recorder, and Figure 3 is a diagram showing the relationship between humidity and elongation of recording paper. FIG. 3 is a diagram showing a more specific example. DESCRIPTION OF SYMBOLS 1... Orthogonal converter, 2... Amplifier, 3... Servo motor, 4... Sliding resistance, 5... Recording mechanism, 6
...Humidity detector, 7...Correction circuit. 〓〓〓〓

Claims (1)

[Scope of utility model registration request] a fixed scale plate for indicating a measured value; a recording mechanism for indicating a measured value on the scale plate and recording it on a recording paper in response to a measurement input signal; and a humidity detector for detecting the humidity of the recording paper. a measurement circuit that corrects the recording span based on the detection signal of the humidity detector; and a measurement circuit that corrects the recording span of the recording mechanism according to the expansion and contraction of the recording paper when the detection signal of the humidity detector is applied to the measurement circuit. and a changeover switch provided between the measuring circuit and the humidity detector, which switches the scale plate to indicate the measured value by the recording mechanism when the detection signal of the humidity detector is not applied to the measuring circuit. A recorder characterized by: