JPS6158837B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a display device.

In a display device, display elements with different colors on the front and back sides are arranged in parallel in the vertical and horizontal directions so that they can be freely reversed, and the display elements are reversed using the attractive force of an electromagnet according to the display pattern. It is known that attempts have been made to display patterns according to the colors that appear.

That is, as shown in FIGS. 1 and 2, the display surfaces 1a and 1b of the display element 1 have different colors, and a hollow elongated hole 2 is formed inside. A shaft 3 extending laterally (horizontally) is inserted through the elongated hole 2, and the display element 1 is suspended from this shaft 3. Specifically, a large number of shafts 3 are arranged in parallel along the lateral direction (horizontal direction), and a plurality of display elements 1 are inserted into each shaft. This allows a large number of display elements 1 to be arranged in parallel in the vertical and horizontal directions. An electromagnet is used to invert each display element 1. For this purpose, a magnetic piece (for example, an iron piece) 4 is embedded in the display element 1 in advance near one end in the vertical direction. In order to balance the weight, it is preferable to bury a non-magnetic piece of the same weight as the magnetic piece near the other end. The electromagnets are inserted through one shaft and arranged horizontally in the same number as the display elements. All the electromagnets are raised and lowered in sequence, and in the process of raising and lowering, each electromagnet faces each display element arranged in the vertical direction in turn. Each time the electromagnet faces each display element, the excitation of the electromagnet is controlled according to the display pattern, and is inverted or non-inverted depending on the control mode. When the electromagnet rises, magnetic piece 4
If it is on the lower end side, it is similarly reversed.

By the way, as shown in the top view of FIG. 3, when electromagnets face all of the display elements supported by one shaft 3, for example, one electromagnet 5A
Assume that the adjacent electromagnet 5B is moved over and the adjacent electromagnet 5C is excited. At this time, display element 1 facing electromagnets 5A and 5C
As described above, the magnetic pieces in A and 1C are magnetized to the polarity shown in the figure and are thereby reversed. However, in this case, in addition to one closed magnetic path connecting the electromagnet 5A and the magnetic piece in the display element 1A, and another closed magnetic path connecting the electromagnet 5C and the magnetic piece in the display element 1C, the electromagnets 5A, 5B, 5C A third closed magnetic path connecting the magnetic pieces in the display elements 1A, 1B, and 1C is completed. Due to this third closed magnetic path, the iron core of the electromagnet 5B is magnetized to the n-pole and s-pole as shown in the figure, and the magnetic pieces in the display element 1C are also magnetized to the n-pole and s-pole as shown in the figure. , display element 1
C now rotates in the same way as other display elements. In reality, this rotation is minute, but a hook piece that moves up and down together with the electromagnet is usually provided, and this hook piece engages the end of the rotated display element to perform the reversing operation. Since the display element is assisted, if the display element engages with the hook even by a slight rotation as described above, the display element will be completely reversed.

In order to prevent such unexpected situations from occurring,
In other words, in order to prevent the aforementioned third closed magnetic path from being completed, two of each electromagnet are
Electromagnets belonging to the same group have the same polarity at the ends of their iron cores, and opposite ends of the iron cores of the electromagnets belonging to the same group have opposite polarities. It is conceivable to magnetize the electromagnets so that the electromagnets of the adjacent pairs are magnetized so that the iron core ends and the opposing ends of the electromagnets of the adjacent pairs have the same polarity. Magnetization in this manner can be achieved by changing the winding direction of the coil of each magnet or by changing the polarity of the DC power source that excites the coil. To further explain the above magnetization relationship with reference to FIG. 4, among the electromagnets 5A to 5F facing the display elements 1A to 1F, the electromagnet 5A,
5B, electromagnets 5C, 5D, electromagnets 5E, 5F, etc. are each set as one set, and electromagnets 5A, 5B, 5E, 5
For F, if the left end of each core is magnetized so that it becomes the north pole and the right end becomes the south pole, then for the middle pair of electromagnets 5C and 5D, the right end of each core becomes the north pole. Magnetize so that the north pole becomes the south pole and the left end becomes the south pole. At this time, the opposite ends of the iron cores of both electric stones belonging to the same group have different polarities,
Also, the end of the core of an electromagnet belonging to one set and the end of the core of the electromagnet opposite to this belonging to an adjacent set are magnetized with the same polarity.

With such a configuration, for example, the electromagnet 5
When A and 5C are excited at the same time, the right end of the iron core of electromagnet 5A and the left end of the iron core of electromagnet 5C will be magnetized with the same polarity, so the third closed magnetic path as described above will be The iron core of the electromagnet 5B, which has not been completed and therefore is not energized, is not magnetized at all. Note that in this configuration, for example, the electromagnets 5B, 5
When E is excited at the same time (electromagnets 5C and 5D are de-energized), the right end of the iron core of electromagnet 5B and the left end of the iron core of electromagnet 5E are magnetized with different polarities. A third closed magnetic path passing through the iron cores 5E to 5E is completed, but in this case, since the electromagnets 5B and 5E are separated by a considerable distance, the magnetic resistance is large and poses almost no problem in practice.

However, on the other hand, the following disadvantages occur. That is, when the two electromagnets of each set are excited, since the opposing ends of the iron cores of both electromagnets have different polarities, one closed magnetic path passing through both electromagnets is completed. As is well known, when a plurality of magnets are connected in series, the total magnetomotive force is not a multiple of the magnetomotive force of each magnet, but only about the magnetomotive force of one magnet. Therefore, if a closed magnetic path is completed when both electromagnets in one set are excited, the magnetomotive force of one electromagnet will be approximately half,
The force that attracts the iron core inside the display element is also halved. Therefore, the display element could not be reliably reversed, and a so-called reversal error sometimes occurred.

An object of the present invention is to prevent magnetic interference due to completion of a closed magnetic path by adjacent electromagnets when electromagnets for reversing display elements are arranged in parallel.

An embodiment of this invention is shown in FIG. This embodiment is an example using the configuration shown in FIG. 4, and the magnet 10 is
It is placed between the core ends of both electromagnets forming a pair. At this time, the polarity of the magnet 10 is made the same as that of the end facing the electromagnet core. For example, the magnet 10 placed between the electromagnets 1A and 1B is configured such that its left side is an S pole and its right side is an N pole. The magnet 10 may be a permanent magnet or an electromagnet. However, the magnetomotive force of the magnet 10 must not be such as to rotate the display element by itself.

According to the above configuration, as in Figure 4, when the electromagnets on both sides of one electromagnet are excited, the iron core of the one electromagnet becomes magnetized and causes the display element to rotate. Of course, this is not the case, but when both electromagnets in one set are excited at the same time, for example when electromagnets 5A and 5B are excited at the same time, there is a difference between the N end of the iron core of electromagnet 5B and the S end of the iron core of electromagnet 5A. The lines of magnetic force that are heading towards it cannot move towards the S end of the iron core of the electromagnet 5A because they repel the lines of magnetic force from the magnet 10 that is between them. Therefore, the lines of magnetic force of the electromagnet 5B are directed against the magnetic field lines in the display element that are facing it. It will only pass through one side. The same is true for the electromagnet 5A. As a result of the above, magnetic interference between electromagnets belonging to the same group can be avoided.

Note that the present invention is not limited to a configuration in which two (or three or more) electromagnets are configured as a set as shown in FIG. In short, when the magnetic poles of the opposing ends of the cores of adjacent electromagnets have different polarities, the magnet 10 may be placed between them so that the opposing ends of the cores have the same polarity. In this way, the presence of the magnet 10 prevents the third closed magnetic path from being completed as described above. However, if a plurality of electromagnets are combined into one set as shown in FIGS. 4 and 5, and the magnets 10 are arranged between the electromagnets belonging to the set, the number of magnets 10 used can be reduced, which is convenient.

As described in detail above, according to the present invention, it is possible to reliably prevent malfunctions of the display element due to magnetic interference between adjacent electromagnets, thereby reliably eliminating erroneous display.

[Brief explanation of the drawing]

Figure 1 is a side sectional view showing the relationship between the display element and the electromagnet, Figure 2 is a perspective view of the display element, Figures 3 and 4.
The figure is a plan view of a conventional example, and FIG. 5 is a plan view showing an embodiment of the present invention. 1,1A~1F...display element, 5,5A~5F
...Electromagnet, 10...Magnet.

Claims (1)

[Claims] 1. In a display device in which each display surface has a different color and a large number of rotatably supported display elements are arranged vertically and horizontally, a plurality of electromagnets are arranged in parallel to attract and rotate the display elements. Also, a display device in which a magnet having the same polarity as the opposing iron core end portions is arranged between the opposing iron core ends of mutually adjacent electromagnets having different polarities.