JPS638943Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a drive circuit for a display device that changes the display state by magnetic drive means.
It is an object of the present invention to provide a display device drive circuit that can drive a plurality of display devices arranged in a matrix with a particularly simple configuration.

The present applicant previously proposed a display element as shown in FIG. This display element includes, for example, a disc-shaped display board 1 and a protrusion 2 protruding from the back side of this display board 1.
A lever 3 guides the tip of the protrusion 2 along an arc of radius R, and one end engages with a shaft P protruding from the upper end of the display board 1, and is rotated at an angle of 90 degrees by an electromagnetic drive device 4. It is composed of a lever 5 that is rotated, a rod 6 that connects the lever 5 and the electromagnetic drive device 4, and a case 7 made of a resin material that houses these. Front panel 7 facing display panel 1 of case 7
A is made of a transparent resin material, and when the display panel 1 is in contact with the front panel 7a, the white color painted on the surface of the display panel 1 can be seen through the front panel 7a of the case 7. On the other hand, when the electromagnetic drive device 4 is driven and the rod 6 is pulled rearward, the lever 5 is rotated until it becomes parallel to the side wall surface of the case 7. Therefore, the display panel 1 changes from the state indicated by the dotted line in the figure to a state in which its display surface is in contact with the side wall surface of the case 7. Therefore, in this state, the inside of the case 7 can be seen through the front plate 7a of the case 7. By using a light-shielding resin material for the side walls of the case 7, the interior appears dark and appears black from the front.

The electromagnetic drive device 4 includes an electromagnet 4a and the electromagnet 4.
Permanent magnets M ₁ and M ₂ are attached to both ends of the lever 4b so as to face both ends of the lever 4b. The magnets M ₁ and M ₂ have magnetic poles of the same polarity facing both ends of the electromagnet 4a. In this way, the magnetic poles of the electromagnet 4a are reversed, so that the magnets _M1 and _M2 are alternately connected to the electromagnet 4a.
By pulling or pushing the rod 6, the display board 1 can be controlled to be in contact with the front plate 7a of the case 7 and in the state in which it is in contact with the side wall surface of the case 7. For example, a white display state and a black display state can be created.

For example, as shown in FIG. 2, such display elements are arranged in a matrix of 7 vertical rows L ₁ to L ₇ and 5 horizontal columns M ₁ to _{M 5} , and the display plate of a predetermined display element among them is By controlling the display to a set state, that is, a white display state, for example, it can be used as a display device for displaying numbers, characters, etc.

This invention relates to a drive circuit for each display element in such a display device, and is particularly designed to reliably control a large number of display elements.

In this invention, two coils are provided in the electromagnet 4a of the electromagnetic drive device 4 of each display element, and by passing current through one coil, the display board 1 is brought into contact with the display surface, that is, in a set state, and when the other coil is By applying current, the display panel 1 is brought into contact with the side wall of the case 7 and operated to be controlled to a reset state. Therefore, one coil will be referred to herein as a set coil, and the other coil will be referred to as a reset coil.

FIG. 3 shows an embodiment of this invention. Reference numeral 8 in the figure indicates the display device explained in FIG. As described above, the display device 8 is configured as a display device for one number or letter by arranging display elements in a matrix of seven rows in the vertical direction and five columns in the horizontal direction. Each display element has a set coil 9 and a reset coil 1.
0, and one end of each set coil 9 and reset coil 10 is connected to the row line. That is, for each row L ₁ to _{L 7} of the display elements, a set row line 11a,
11b, 11c, 11d, 11e, 11f, 11
g and reset row lines 12a, 12b, 12c, 1
2d, 12e, 12f, and 12g are provided, and one end of each of a set coil 9 and a reset coil 10 is connected to these row lines 11a to 11g and 12a to 12g through diodes, respectively. The other ends of the set coil 9 and reset coil 10 of each display element are commonly connected and connected to a column line. In this example, of the 7 vertical rows of display elements, the upper 3 rows L ₁ to L ₃ and the lower 4 rows L ₄ to
This shows the case where L ₇ is controlled separately. That is, two column lines 13a-14a, 13b- for each column.
14b, 13c-14c, 13d-14d, 13
e-14e, one column line 13a, 13b,
13c, 13d, and 13e are set coils 9 and reset coils 10 for display elements up to the third row from the top.
connect the common connection points of the other column lines 14a, 14
The common connection points of the set coils 9 and reset coils 10 of the lower four rows of display elements are connected to b, 14c, 14d, and 14e, respectively.

These seven set row lines 11a to 11g and reset column lines 12a to 12g, and a total of ten column lines 13a to 13e and 14a to 14e, are each connected to a power source through a thyristor. That is, in this example, four thyristors 15a to 15d are prepared for the seven setting row lines 11a to 11g, and these four thyristors 15a to 15d control the seven setting row lines 11a to 11g. Setting row lines 11a to 11c from the top to the third row
and the four rows of set row lines 11d to 11g below it.
The setting power is applied in a time-division manner. In reality, four thyristors 15a to 15d simultaneously apply setting power to these seven setting row lines 11a to 11g, but the power is applied to each row in a time-division manner on the column lines 13a to 13e and 14a to 14e. By selecting a line, the upper three lines and the lower four lines are controlled in a time-sharing manner. By dividing the row control into two stages in this way, there is an advantage that the number of thyristors controlling the row lines can be reduced to about half.

To explain the connection relationship in more detail, the anodes of the thyristors 15a to 15d are commonly connected to the positive terminal of the power source 16. Further, the cathode side of each thyristor 15a to 15d is first connected to the lower four rows of set row lines 11d to 11g, and the thyristor 15 is connected to the upper three rows of row lines 11a to 11c.
Connect the cathodes of b to 15d. Similarly, the cathodes of the reset thyristors 17a to 17d are connected to the lower four rows of reset row lines 12d to 12g, and the upper three rows of reset row lines 12a to 12c are connected to the cathodes of the reset thyristors 17a to 17d.
The cathodes of the thyristors 17b to 17d are connected to the thyristors 17b to 17d.

On the other hand, a total of 10 column lines 13a to 13e and 14a to
10 thyristors 18a-18 for 14e
j is prepared. 5 thyristors 18a, 18c, 18e, 18g, 1 out of 10 thyristors
8i anodes to the column lines 13a, 13b, 13c,
13d, 13e, and other column lines 14a, 14b, 14c, 14 are connected to the anodes of the other five thyristors 18b, 18d, 18f, 18h, 18j.
Connect d and 14e. These 10 thyristors 1
Each cathode of 8a to 18j is connected in common, and the power supply 1
It is connected to the negative terminal of No.6.

Thyristors 15a-15d and 17a-17d
A data signal to be displayed is applied to each gate. This data signal is, for example, information such as numbers or characters for time display. For example, in the case of time display, this information is provided by changing the address signal every minute and reading it out from the read-only memory 19. This example shows the case where one 4-bit output type read-only memory is used, and the information for one line of the display 8 is read out twice from this one read-only memory. be. Therefore, in the first reading, the display data up to the third row on the upper side of the display device 8 is read out, and each set thyristor 15a to 15d and reset thyristor 17a to 17d is activated by the H logic and L logic of the read data. Controlled on.

On the other hand, the thyristors 18a to 18j are counters 20
are sequentially turned on in synchronization with reading from the read-only memory 19. In other words, thyristor 1
While the first display information is being given to 5a to 15d and 17a to 17d, the thyristor 18a is controlled to be turned on. Therefore, the first column of the display device 8
Power for setting or resetting is applied to the display elements up to the upper three rows of _M1 , and their display states are controlled to correspond to the readout output of the read-only memory 19. Next, when the second information is read from the read-only memory 19, the thyristor 18b becomes conductive, and power for setting or resetting is applied to the lower four display elements of the first column _M1 . In this way, the state of one column of display elements is controlled by reading information twice, and the states of all columns M ₁ to _{M 5} of the display device 8 are controlled by reading information 10 times in total. Ru. In this example, the display device 8 is a display device for one digit of numbers and one character for letters, and by preparing such a display device 8 with multiple digits, it is possible to display the time or advertisement text. For multi-digit display, the set and reset thyristors 15a to 15d and 17a to 17d are shared for each digit.
The thyristors 18a to 18j are added according to the number of digits. In addition, the power supply 16 is read-only memory 1
Pulse-like power is output in synchronization with the readout pulse No. 9, and each display element is controlled to set and reset states by the pulse-like power. Therefore, each thyristor 15a to 15d, 17a
~17d and 18a~18j are turned off by the fall of the pulsed power.

As explained above, according to this invention, the setting power and the resetting power are given to the set and reset coils 9 and 10 of each display element in a time-sharing manner for each column by the thyristor, so it is relatively The display state of the display device can be changed using a small power source. Moreover, since power is applied to each set coil 9 and reset coil 10 through the thyristor, the thyristor has higher durability than other semiconductor switch elements such as transistors, and can constitute a highly reliable display device.

[Brief explanation of the drawing]

FIG. 1 is a plan view illustrating an example of a display element suitable for use in this invention, FIG. 2 is a front view showing an example of the external appearance of a display device according to this invention, and FIG. 3 is an embodiment of this invention. FIG. 8: Display device, 9: Set coil, 10: Reset coil, 11a to 11g: Set row line, 1
2a-12g: Reset row lines, 13a-13
e, 14a-14e: row line, 15a-15d, 1
7a-17d, 18a-18j: Thyristor, 1
6: Power supply.

Claims (1)

[Scope of utility model registration request] A plurality of display devices are arranged in a matrix in which a display state is changed by rotating a plate-shaped display element by means of a magnetic drive means having a set coil and a reset coil, and the set coils of the plurality of display devices are arranged in a matrix. and one end of the reset coil is connected to a row line, and the other ends of the set coil and reset coil are connected to a column line, each of these row lines is connected to one end of a power supply through a first thyristor, and each of the column lines is connected to a second The first thyristor is connected to the other end of the power supply through a thyristor, the first thyristor is selectively made conductive by a display signal, the change in the display signal is counted by a counter, and the output of the counter is used to sequentially selectively turn the second thyristor on. A drive circuit for a display device which is electrically conductive and selectively controls the display elements to set and reset states for each column.