JPH0345267Y2 - - Google Patents

Description

[Detailed description of the invention] This invention expresses the value output from a display device, especially an electronic computer, etc. and expressed by a digital code, etc., as a physical quantity called rotation angle, so that it can be grasped intuitively by humans. This relates to a display device for easily displaying analog values.

Conventionally, this type of display has either simply decoded a digital code and used the result to drive a light emitting device such as a lamp or light emitting diode, or converted it into a rotation angle using a servo mechanism using a pulse motor. There was a method to convert the digital code directly into an analog voltage and current signal, and to make the meter swing with this analog electrical signal. However, with methods similar to , there is a limit to the power and persuasiveness that is one of the important elements of the display function.For example, when rotating a large pointer with a special shape, There was a problem. In other cases, although the above problems can be solved, it is generally very expensive.

The present invention attempts to solve the above problems by using an inexpensive servo system consisting of a DC motor and a photointerrupter, which stores a digital code representing the displayed value that is output together with a strobe signal from a digital code output device. a register for decoding the stored code, a decoder for decoding the stored code, an exclusive OR circuit for comparing the decoder output with signals output from a plurality of photo interrupters for detecting the rotation angle of the pointer; a logical sum circuit that calculates the logical sum of the logical sum circuit outputs;
an RS flip-flop that is reset by the output of the OR circuit and set by the strobe signal; and a motor drive that powers on the DC motor that drives the pointer while the output of the RS flip-flop is at its true value. It includes a circuit and a shield plate that rotates at the same time as the indicator needle and has a structure that allows light to pass through only the photo interrupter corresponding to the position indicated by the indicator needle, and displays the digital code as the rotation angle of the indicator needle. It is characterized by

The present invention is used, for example, to display wind directions in 16 directions using arrow feathers on an industrial instrumentation panel, and to obtain the data from a digital telemeter output or an electric computer process output. Embodiments of the present invention will be described with reference to the drawings. 1st
The figure is a block diagram of an embodiment of the present invention, in which a strobe signal 2 is output from a device 1 that outputs a digital code.
A data signal 3 consisting of a plurality of bits is output. Data signal 3 is written to register 4 by strobe 2 and latched. Furthermore, the strobe 2 simultaneously sets the RS flip-flop 5, and the output of the flip-flop 5 is connected to the input of the DC motor drive circuit 6. While the output of the flip-flop 5 is at the true value, the motor drive circuit 6 is The DC motor 7 is rotated in a fixed direction. The rotational speed of the motor 7 is such that when the drive from the motor drive circuit 6 is stopped, the position of the indicator needle does not shift due to the mechanical inertia of the motor itself, and the movement of the indicator needle can be tracked visually. The decision must be made based on conditions such as the ability to
Generally, a geared motor that rotates one revolution in about 4 seconds is preferable. Results of rotation of motor 7 8-1 to 8-n
One by one of the n position detection photo interrupters is selected one by one, and the output is 9-1 to 9-1.
It is output to an exclusive OR circuit 9-n. On the other hand, the output of the register 4 is developed into individual stop position signals by the decoder 10, and similarly the exclusive OR circuit 9-
It is connected to other terminals of 1 to 9-n. What is important here is that the number of output bits of the decoder 10 is equal to n, and that the stop position signal output from the decoder 10 must correspond to the mounting position of the photointerrupter. Therefore, for example, when the i-th position signal is output as a true value from the decoder 10, the output is obtained from the exclusive OR circuit 9-i only when the signal is detected by the photo interrupter 8-i. It turns out. The output signals of the exclusive OR circuits 9-1 to 9-n are input to the OR circuit 11, and its output is connected to the reset terminal of the flip-flop 5, so the output signal of the exclusive OR circuit 9-i is The flip-flop 5 is reset through the OR circuit 11, and when the output of the flip-flop 5 becomes false, the motor drive circuit 6 stops the rotation of the motor 7.

FIGS. 2a and 2b show a side view and a front view of the part where the photo interrupter detects the rotational position of the DC motor.
3 and a display hand 14 are attached, and rotate as the motor 7 rotates around the shaft 12.
Reference numeral 15 designates a plate so that when a person views this display from the front, only the display needle 14 is visible and the internal structure is not visible. Mark the scale corresponding to the amount to be instructed and fix it in an appropriate location. Shade board 13
A notch is made in the first part 16, and when the photo interrupter 16 passes through the photo interrupters 8-1, 8-2, . I'll keep it. Therefore, as the motor 7 rotates, the photo interrupters 8-1, 8-2, .
will pass through, and its electrical output will be obtained in turn. These are taken as temporal relationships and shown in FIG. A is output data from an electronic computer, etc., and is synchronized by a strobe signal b.
c is the RS flip-flop shown in FIG.
This indicates that it was set by. d means the rotational operation of the DC motor, which starts rotating by setting c. e-1 to e-n indicate output signals of the photo interrupter. Here e-i
When is output, c is reset and d stops its rotation.

According to the present invention, a value expressed by a digital code or the like can be expressed by a physical quantity called a rotation angle using an inexpensive servo system.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment of the present invention;
Figures a and b are side and front views of the portion where the photointerrupter detects the rotational position of the DC motor, and Figure 3 is a time chart of the operation of Figure 1. DESCRIPTION OF SYMBOLS 1... Digital code output device, 2... Strobe signal, 3... Data signal, 4... Register, 5... Flip-flop, 6... DC motor drive circuit, 7... Motor, 8... Photo interrupter, 9 ...Exclusive OR circuit, 10...Decoder, 11...OR circuit.

Claims (1)

[Scope of utility model registration request] A register that stores a digital code representing a display value that is output together with a strobe signal from a digital code output device, a decoder that decodes the stored code, and a plurality of photo interrupters that detect the rotation angle of the pointer. an exclusive OR circuit that compares the signal output from the decoder with the output of the decoder; an OR circuit that ORs the outputs of the exclusive OR circuit; an RS flip-flop that is set by A display device comprising a shield plate having a structure that allows light to pass through only a photo interrupter corresponding to the indicated position of the needle, and displaying a digital code as a rotation angle of the indicator needle.