JPH0412471B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a display device that displays image information such as characters, symbols, and figures using a plurality of pixel components, and is particularly suitable for forming a large screen. Regarding.

[Prior art]

Conventionally, large-screen display devices that display images using multiple pixel components include mechanical devices in which the pixel components are mechanically driven by a solenoid, etc., and devices that use light bulbs, fluorescent tubes, etc. There was also an electric type that used an electro-optical conversion device as a pixel component.

However, the mechanical type (b) Power consumption is extremely large.

(b) Abnormal noise occurs when driving each pixel component.

(c) Since individual pixel components and mechanisms for driving them are not independent, it is not easy to change the design if display devices with various total numbers of pixels are required.

(d) The structure is complicated and many expensive drive sources are required, resulting in high manufacturing costs.

(e) The overall weight is very heavy, so it cannot be installed easily.

There were other drawbacks.

Also, in the conventional electric display device, (a) power consumption is extremely large.

(b) Since the image is displayed by blinking the electro-optical conversion device, the image cannot be displayed clearly enough in a bright place.

(c) Manufacturing costs are high because a large number of expensive electro-optical conversion devices and a large-capacity power supply are required.

There were other drawbacks.

[Purpose of the invention]

The present invention was made in order to eliminate the above-mentioned conventional drawbacks, and the power consumption can be extremely reduced, no abnormal noise is generated when driving each pixel component, and each pixel component and The mechanism for driving them has independence for each pixel, and by simply combining the necessary number of these, display devices with various total numbers of pixels can be easily obtained, reducing manufacturing costs. It is an object of the present invention to provide a display device that can display images clearly even in a bright place, and can be extremely lightweight.

[Summary of the invention]

The display device according to the present invention includes a unit main body having an opening on the front surface, a shielding member rotatably supported by the unit main body and opening and closing the opening, and a display device provided integrally with the shielding member or provided with the shielding member. A wrapping body linked to a shield, a wrapping material having at least a part of a shape memory alloy portion wrapped around the wrapping body, and a force that causes elongation deformation in the shape memory alloy. The above-mentioned object is achieved by arranging a plurality of pixel units each having a means for acting on the shape memory alloy, and further comprising an energizing means for selectively energizing the shape memory alloy of the plurality of pixel units. It is.

〔Example〕

Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

1 to 5 show one pixel unit 1 in this embodiment. To explain this, the unit main body 2 has a box shape with an opening 2a provided on the front side, and a shield shaft 3 is fixed near the opening 2a of the unit main body 2. As shown in FIGS. 3 and 5, a bearing tube 4 made of fluororesin is rotatably fitted to the shield shaft 3. As shown in FIGS. Here, the friction between the bearing tube 4 and the shield shaft 3 is made sufficiently small, so that the bearing tube 4 rotates smoothly with respect to the shield shaft 3.

A central portion of a substantially plate-shaped shield 5 is rotatably fitted into the bearing tube 4 . Here, between this shield 5 and the bearing tube 4,
An appropriate amount of frictional force is applied, and when the torque transmitted from the bearing tube 4 to the shield 5 is less than a predetermined value, the bearing tube 4 rotates integrally with the shield 5. However, when the torque reaches a predetermined magnitude, the bearing tube 4 begins to slip against the shield 5.

The rotatable range of the shield 5 is restricted by stoppers 6 and 7 provided on the inner surface of the unit body 2. When the shield 5 comes into contact with the stopper 6, the shield plate 5 becomes parallel to the front surface of the unit main body 2 and completely closes the opening 2a, as shown by the solid line in FIG. On the other hand, when the shield 5 is brought into contact with the stopper 7, the shield 5 opens in a direction perpendicular to the front surface of the unit main body 2, as shown by the dashed line in FIG. 2a is opened so that the inner surface of the unit body 2 can be seen from the outside.

The entire inner surface of the unit body 2 and the inner surface 5a and end surface 5b of the shield 5 are black, while the outer surface 5c of the shield 5 is white.

As clearly shown in FIG. 3, terminals 8 and 9 are fixed to the inner surface of one side wall of the unit main body 2, and a pulley 10 is rotatably supported. Also, as shown in Figure 5,
A wrapped body 11 made of a flexible tube material is rotatably fitted into the bearing tube 4 . Here, an appropriate amount of frictional force is applied between the wrapped body 11 and the bearing tube 4, so that the torque transmitted from the wrapped body 11 to the bearing tube 4 is controlled to a predetermined level. When the torque is less than or equal to the torque, the wrapped body 11 rotates integrally with the bearing tube 4. However, when the torque reaches a predetermined value, the wrapped body 11 rotates integrally with the bearing tube 4.
It is starting to slip against the opponent.

One end of a tension coil spring 12 is attached to the terminal 8, and one end of a linear shape memory alloy 14 such as a Ti-Ni alloy is attached to the other end of the spring 12 via a connector 13. The end of the is attached. The shape memory alloy 14 is wound around the body 11 in a crossed state, and around the pulley 10 in a non-crossed state, and the other end is fixed to the terminal 9.

Note that here, the shape memory alloy 14 memorizes a straight shape, but as will become clear later, in this embodiment, the shape memory alloy 14 is mainly deformed in the length direction and shape recovery (i.e. , expansion and contraction of the shape memory alloy 14), there is no problem even if the shape memory alloy 14 records a curved shape.

In this embodiment, a required number of pixel units 1 having the configuration described above are arranged two-dimensionally as shown in FIG.
One display device 18 is configured. In addition, when combining a plurality of pixel units 1 in this way, for example, each pixel unit 1 may be directly connected to each other, or a panel-shaped support body in which each pixel unit 1 is accommodated may be prepared, Each pixel unit 1 may be mounted on the support.

FIG. 6 shows a control system of the display device 18. In this figure, 15 is a control circuit, which inputs an image information signal instructing the image to be displayed on the display device 18, and based on the signal, the drive circuit 1
6, among the plurality of pixel units 1, "black"
The current is made to flow through the shape memory alloy 14 of the object to be used.

The drive circuit 16 is connected to one end of the shape memory alloy 14 via the conductor 20, the terminal 8, the spring 12, and the connector 13, and also to the conductor 21 and the terminal 9.
They are electrically connected to the other end of the shape memory alloy 14 via the respective ends. Further, the control circuit 15
Instead of energizing the shape memory alloys 14 of the pixel units 1 to be rendered "black" at the same time, the shape memory alloys 14 are energized at staggered timings, which will be explained in detail later.

Next, the operation of this embodiment will be explained.

First, the operation of each pixel unit 1 will be explained. In the initial state, the drive circuit 16 is not energizing the shape memory alloy 14 and the alloy 14 is cooling, so the alloy 14 is
Due to the force of 2, the memory shape is stretched and deformed by a certain amount ΔL. For this reason, pulley 2
is in the most counterclockwise rotated state in FIG. Further, at this time, the shield 5 contacts the stopper 6 to close the opening 2a.

Next, when a pulse current of an appropriate magnitude is passed from the drive circuit 16 to the shape memory alloy 14, the alloy 1
4 is heated by Joule heat, reaches a predetermined temperature or higher, starts phase transformation, and attempts to return to its memorized shape due to the shape memory effect. For this reason, shape memory alloy 1
4 expands and contracts toward the length of the memory shape (note that since the shape memory alloy 14 is linear, the recovery stress from bending deformation is small, so it shows only a very slight shape recovery with respect to bending deformation. ).

As the shape memory alloy 14 contracts, the wrapped body 11 rotates clockwise against the spring 12, together with the bearing tube 4 and the shield 5. Then, the shield 5 will soon become the third
It comes into contact with the stopper 7 as shown by the dashed line in the figure,
It is no longer possible to rotate any further, and the opening 2a is in an open state. However, the shield 5 and the bearing tube 4
or between the bearing tube 4 and the wrapped body 1
Since a slip occurs between the shape memory alloy 14 and the shape memory alloy 14, even after the shield 5 contacts the stopper 7 as described above, the shape memory alloy 14 continues to contract and returns to the length of the memorized shape.

Next, from the drive circuit 16 to the shape memory alloy 14
When the application of the pulse current to the shape memory alloy 14 ends, the shape memory alloy 14 begins to cool down, and the force of the spring 12 causes the shape memory alloy 14 to cool down again.
It begins to undergo elongation deformation. Therefore, the wrapped body 11 rotates counterclockwise in FIG. 3 together with the bearing tube 4 and the shield 5.
Then, the shield 5 eventually comes into contact with the stopper 6,
It cannot rotate any further, and the opening 2a is in a closed state. On the other hand, between the shielding body 5 and the bearing tube 4 or between the bearing tube 4 and the wrapped body 11
Because a slip occurs between the shield 5 and the stopper 6 as described above, the shape memory alloy 14 continues to be stretched and deformed to a length that balances the force of the spring 12 even after the shield 5 comes into contact with the stopper 6 as described above.

Thereafter, when the drive circuit 16 energizes the shape memory alloy 14, the shield 5 opens the opening 2a, and when the energization is stopped, the shield 5 closes the opening 2a.

Furthermore, when the shield 5 opens the opening 2a as described above, the inner surface of the unit main body 2 becomes visible from the outside, so the pixel unit 1 displays "black"; When the section 2a is closed, the inner surface of the unit body 2 is no longer visible from the outside, and only the outer surface 5c of the shield 5 is visible, so that the pixel unit 1 displays "white".

Therefore, in the display device 18 of FIG.
Among the plurality of pixel units 1, the shape memory alloy 14 of the pixel unit 1 that should be ``black'' is energized, while the pixel unit 1 that should be ``white'' is not energized; Display the image on the display device 18
It is possible to display the .

Next, the method of energizing each pixel unit 1 will be explained in more detail.

When the control circuit 15 receives the image information signal,
Shape memory alloy 1 of pixel unit 1 that should be “black”
4 through the drive circuit 16, but at this time, the control circuit 15 does not apply the pulse current to all the pixel units 1 which should be "black" at the same time, but as shown in FIG. A pulse current is applied to the shape memory alloy 14 of each pixel unit 1 to be "black" at different timings (in FIG. 8, the shape memory alloy 14(1),
14(2), 14(4), and 14(n), but not the shape memory alloys 14(3) and 14(5)).

By the way, even if the power supply to the shape memory alloy 14 is stopped, the temperature of the alloy 14 does not drop instantly, so the shield 5 remains open for a while after the power supply. In this embodiment, for example, when a current of 6 [V] and 1 [A] is passed through the shape memory alloy 14 for 0.05 [seconds], the shield 5
can be opened for about 1 to 2 seconds (this time depends on the volume of the shape memory alloy 14, etc.).

Because of the delay characteristic of the shape memory alloy 14, even if the shape memory alloy 14 of each pixel unit 1 is energized at different timings as described above,
Each pixel unit 1 can be opened almost simultaneously. By energizing the shape memory alloy 14 of each pixel unit 1 at different timings as described above, the power consumption of the entire device 18 can be extremely reduced.

Generally, when a shape memory alloy is subjected to repeated deformation and shape recovery, the memory shape of the shape memory alloy is not stabilized and changes until this repetitive operation is performed a considerable number of times. For example, in the case of thin wires made of Ti-Ni alloy, which is a type of shape memory alloy, the thin wires are stretched and deformed by applying tensile stress within the stress range (300 MPa) that allows shape recovery, and then the thin wires are heated to shape the wires. If the deformation-shape recovery operation of recovery is repeated ¹⁰⁵ times, the memorized shape of the thin Ti-Ni alloy wire will be elongated by nearly 20%.

For this reason, in conventional thermo-mechanical energy conversion devices using shape memory alloys, as the shape memory alloy is repeatedly subjected to deformation and shape recovery operations, the operating range of the shape memory alloy changes greatly.
This caused the inconvenience that the device would no longer function properly. In order to prevent such inconveniences, it is necessary to frequently perform adjustment work to operate the shape memory alloy within its normal operating range.

However, in this embodiment, such inconvenience does not occur. To explain this, in this embodiment as well, while the number of repetitions of the elongation deformation and shape recovery operations of the shape memory alloy 14 is small,
Each time this operation is repeated, the length of the memorized shape of the shape memory alloy 14 increases, so the rotation range of the wrapped body 11 changes accordingly. However, in this embodiment, the rotatable range of the shield 5 is restricted to a certain range by the stoppers 6 and 7, and the torque transmitted from the shape memory alloy 14 side to the shield 5 side is limited to a predetermined level. When this happens, slips occur between the wrapped body 11 and the bearing tube 4 or between the bearing tube 4 and the shield 5, so that the length of the memorized shape of the shape memory alloy 14, and eventually the length of the memorized shape of the shape memory alloy 14, as described above, Even if the rotation range of the wrapped body 11 changes, as long as the rotation range of the wrapped body 11 includes the rotatable range of the shield 5 determined by the stoppers 6 and 7, the shield 5
The operating range is always within a certain range (that is, the rotatable range), and no adjustment work is required.

In the above embodiment, when the torque transmitted from the shape memory alloy 14 side to the shielding body 5 side reaches a predetermined level, the torque between the wrapped body 11 and the bearing tube 4 or between the bearing tube 4 By causing a slip between the shielding body 5 and the shielding body 5,
Although it is designed to prevent further torque from being transmitted to the shielding body 5, the shielding body 5 is
When the torque transmitted to the side reaches a predetermined magnitude, the shape memory alloy 14 may slip against the wrapped object 11, and in that case, the wrapped object 11 may be caused to slip. It can also be integrated with the bearing tube 4 or the shield 5.

Further, in the above embodiment, the shape memory alloy 14 itself is directly wound around the wrapped object 11, but a linear non-shape memory alloy material is connected to the shape memory alloy 14, and the non-shape memory alloy material is You may make it wrap around the body 11 to be wrapped.

Further, in the above embodiment, the elastic force of the spring is used to deform the shape memory alloy 14, but
In the present invention, the shape memory alloy may be deformed by a force other than the elastic force, such as gravity, magnetic force, or shape recovery stress of another shape memory alloy.

Further, in the embodiment, the entire inner surface of the unit main body 2, the inner surface 5a of the shield 5, and the end surface 5
b is black, and the outer surface 5c of the shielding body 5 is white, but it goes without saying that these may be a combination of other different colors.

Furthermore, by making the back wall of the unit main body 2 translucent or not providing the back wall, when the shield 5 is opened, the light coming from the back passes through the opening 2a and reaches the viewer. You can make it visible.

〔Effect of the invention〕

By having the above-described configuration, the present invention can () significantly reduce power consumption;

() No abnormal noise occurs when driving each pixel component.

() Each pixel component and the mechanism that drives it (pixel unit) have independence for each pixel, and by simply combining them, display devices with various total numbers of pixels can be easily obtained. can.

() Since the structure is simple and an expensive drive device is not required, manufacturing costs can be reduced even if the total number of pixels is increased.

() Since the drive source is a shape memory alloy, it can be extremely lightweight.

() Since images can be displayed without the need for flashing light emitting devices, images can be displayed clearly even in bright places.

It is possible to obtain excellent effects such as.

[Brief explanation of drawings]

FIG. 1 is a perspective view of one pixel unit in an embodiment of the display device according to the present invention, with the shield closed, and FIG. 2 is a perspective view of the pixel unit with the shield opened. , 3rd
4 is a sectional view taken along the - line in FIG. 3, FIG. 5 is a sectional view taken along the - line in FIG. 3, and FIG. 6 shows the control system in the embodiment. FIG. 7 is a front view showing the entire image apparatus of the embodiment, and FIG. 8 is a timing chart of pulse current applied to the shape memory alloy of each pixel unit in the embodiment. 1...Pixel unit, 2...Unit body, 3
... Shield shaft, 4 ... Bearing tube, 5 ... Shield, 6, 7 ... Stopper, 11 ... Wrapped body, 12 ... Spring, 14 ... Shape memory alloy, 15
. . . control circuit, 16 . . . drive circuit, 18 . . . display device.

Claims (1)

[Claims] 1. A unit main body having an opening on the front surface, a shield rotatably supported by the unit main body to open and close the opening, and a unit provided integrally with the shield or linked to the shield. The present invention includes a wrapped body, a wrapped material having at least a part of a shape memory alloy portion wrapped around the wrapped body, and a means for applying a force that causes elongation deformation to the shape memory alloy. What is claimed is: 1. A display device comprising: a plurality of pixel units arranged in a plurality of pixel units; and an energizing means for selectively energizing the shape memory alloy of the plurality of pixel units.