JPH0341375Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Industrial Application) The present invention relates to a switch device using a light projecting element and a light receiving element.

(Prior Art) As one means for making a switch device contactless, it has been conventionally practiced to utilize a light emitting element such as a light emitting diode and a light receiving element such as a phototransistor. As an example of this type of switch device, conventionally, a light guide member made of plastic or an optical fiber is used to form an optical path between a light emitting element and a light receiving element, and a light path that appears in and out of this optical path according to manual operation is used. A structure equipped with a shielding plate is provided.

(Problems to be Solved by the Invention) The conventional switch device described above not only requires a relatively expensive light guide member or optical fiber, which increases the cost, but also reduces the structure of the movable parts including the shielding plate, etc. There is also the problem that it becomes complicated. In addition, a shielding plate that requires a predetermined operation stroke is required separately from the light guide member or optical fiber, which makes it difficult to reduce the overall size and thickness, and there are problems in that productivity is also poor. .

The present invention was developed in view of the above circumstances, and its purpose is to reduce costs and simplify the structure while being a non-contact type that uses a light emitting element and a light receiving element. It is an object of the present invention to provide a switch device that can be made smaller and thinner, and can also significantly improve productivity.

[Structure of the idea]

(Means for Solving the Problems) A switch device according to the present invention includes a first plate-like member having a light-guiding property, a spacer having a light-shielding property, and a material having an opening and having a light-guiding property. By providing second plate members formed to have substantially the same optical refractive index as the plate members and arranging them in an overlapping manner, a space is created between the first and second plate members. In this state, the first and second plate-like members are provided so as to be substantially parallel to each other, and the upper surface of the second plate-like member is elastically deformed so as to correspond to at least the opening. a light-diffusing layer is formed on the lower surface of the first plate-like member so as to correspond to at least the opening; a light emitting element arranged to project light into the second plate member, and a light emitting element arranged to receive light from the second plate member or the inside of the second plate member, and generates a switching signal in a light receiving state. The configuration is such that a light receiving element is provided respectively.

(Operation) A case will be described in which the light projecting element is arranged to project light into the second plate-shaped member, and the light-receiving element is arranged to receive light from inside the first plate-shaped member. The light projected into the second plate-like member reaches the opening while being totally reflected inside the second plate-like member, and is further reflected by the light-reflecting layer, and then passes through the empty space to the upper surface of the first plate-like member. is irradiated. At this time, the second plate member is in an undeformed state, that is, the first and second plate members are
When the plate-shaped members are substantially parallel to each other, the light irradiated onto the top surface of the first plate-shaped member is The light is totally reflected on its upper surface. Therefore, no light enters the second plate member, the light receiving element is in a non-light receiving state, and no switching signal is output. Further, when the second plate-like member is pressed and deformed by a finger or the like, the angle of light reflection on the light-reflecting layer changes, the angle of incidence of light with respect to the first plate-like member becomes smaller, and the light is transferred to the first plate-like member. The light enters the inside of the plate-like member without being totally reflected on the upper surface of the plate-like member.
Then, the light that has entered the first plate member in this way will be scattered by the light diffusion section, and the light receiving element will receive a part of the scattered light and output a switching signal. . Also, the light projecting element is the first
When the light receiving element is arranged so as to project light into the second plate-like member and the light-receiving element is arranged so as to receive light from inside the second plate-like member, the above-mentioned method is applied based on the principle of so-called light retrograde movement. It works the opposite way.

(Example) In FIGS. 1 and 2, reference numeral 1 denotes a first light guide plate which is a first plate-like member, which is made of, for example, a transparent plastic material and has a light guide property,
Moreover, in this embodiment, it is formed into a rectangular shape. 2
is a light-shielding spacer formed to have the same outer shape as the first light guide plate 1, and has a circular hole 2a in the center thereof to form a hollow portion. The spacers 2 are arranged on the first light guide plate 1 in an overlapping manner. Reference numeral 3 denotes a second light guide plate which is a second plate-like member, and this is formed, for example, from the same material as the first light guide plate 1 and has the same optical refractive index as the first light guide plate 1. The central portion thereof has a circular through-hole portion 3a serving as an opening corresponding to the circular hole 2a. The second light guide plate 3 is formed in the same rectangular shape as the spacer 2, and is arranged on the spacer 2 in an overlapping manner. Reference numeral 4 denotes a light-shielding film made of, for example, plastic and having light-shielding properties and elasticity, and a mirror-like light reflection layer 5, for example, is formed on the lower surface of the film so as to be elastically deformed together with the light-shielding film 4. The light-shielding film 4 is attached to the upper surface of the second light guide plate 3 so as to cover the entire surface thereof, so that the light reflecting layer 5 is attached to the upper surface of the second light guide plate 3. It is located so as to correspond to the through hole portion 3a.

On the other hand, a light diffusing layer 6 is provided on the lower surface of the first light guide plate 1 by applying, for example, a light-scattering paint so as to correspond to the light projecting portion 3a. Furthermore, a reinforcing plate 7 made of a light-shielding material and having the same size as the first light guide plate 1 is attached to the lower surface of the first light guide plate 1 .

Reference numeral 8 denotes a light receiving element, such as a light emitting diode, which is installed so as to face the end surface 3b of the second light guide plate 3 from the side. Reference numeral 9 denotes a light-receiving element, such as a phototransistor, which is installed on the end surface 1a of the first light guide plate 1 opposite to the light-emitting diode 8 so as to face it from the side. Although not shown, the phototransistor 9 is configured to generate a switching signal in its light receiving state. Note that the spaces between the first light guide plate 1, the spacer 2, the second light guide plate 3, the light shielding film 4, and the reinforcing plate 7 may be fixed by, for example, adhesive, or by holders that sandwich each peripheral edge. Just fix it.

According to the above configuration, the light emitted from the light emitting diode 8 reaches the light emitting part 3a while being totally reflected inside the second light guide plate 3, as shown by the arrow in FIG. After being reflected by the layer 5, the light emitting part 3
The upper surface of the first light guide plate 1 is irradiated through the circular hole 2a and the circular hole 2a. At this time, when the first light guide plate 1 and the second light guide plate 3 are in a non-operating state, that is, when the first light guide plate 1 and the second light guide plate 3 are in a parallel state, the first light guide plate 1
The light incident angle θ with respect to the light guide plate 3 becomes equal to each light reflection angle θ' in the second light guide plate 3 and the light reflection layer 5. Also,
In this case, since the optical refractive index of the first light guide plate 1 and the second light guide plate 3 is approximately the same, the light irradiated onto the upper surface of the second light guide plate 3 as described above is transmitted to the upper surface of the second light guide plate 3. (See Figure 1). Therefore, the light emitted from the light emitting diode 8 into the second light guide plate 3 is not transmitted into the first light guide plate 1, and therefore the phototransistor 8 is in a non-light receiving state and the switching signal is not transmitted. It is never output. Furthermore, when the central portion of the light-shielding film 4 is pressed, the light-reflecting layer 5 is deformed to bulge downward, as shown in FIG. As a result, the light reflecting layer 5
The light reflection angle at the light guide plate 1 changes, and the light incidence angle θ with respect to the first light guide plate 1 becomes smaller, so that the light from the light reflection layer 5 enters the first light guide plate 1 without being totally reflected. become. Then, the light that has entered the first light guide plate 1 will be scattered by the light diffusion layer 6, and a part of the scattered light will be scattered through the first light guide plate as shown by the arrow in FIG. The light reaches the end face 1a of the phototransistor 9 while being totally reflected within the phototransistor 9. Therefore, in response to the pressing operation of the central part of the light-shielding film 4, the phototransistor 9
A switching signal is output from
Such an output state is the first state after the above pressing operation is released.
It will be stopped when it returns to the state shown in the figure.

According to the present embodiment described above, the first light guide plate 1, the spacer 2, the second light guide plate 3, and the light shielding film 4 on which the light reflection layer 5 is provided in advance, each having a simple shape and being relatively inexpensive, are provided. The structure is extremely low cost and simple, consisting of simply overlapping the reinforcing plates 7 and 7, and of course, the structure of the movable parts is also extremely simple, which can promote miniaturization and thinning of the entire structure. be. Moreover, in this case, the above-mentioned parts can be simply stacked on top of each other, and each part (including the light diffusion layer 6) can be manufactured using only press technology and printing technology, so productivity can be dramatically increased. It is something. Furthermore, by modifying the shapes of the spacer 2, the second light guide plate 3, etc., it is possible to easily construct a multiple switch, which has the advantage of greatly widening the range of applications.

In the above embodiment, the light emitting diode 8 is
The light-emitting diode 8 and the phototransistor 9 were arranged to face the end surface 3b of the first light guide plate 3, and the phototransistor 9 was arranged to face the end surface 1a of the first light guide plate 1. This is also a good configuration. In this case, when pressing the light shielding film 4, the first
The light emitted from the light emitting diode 8 arranged to face the end surface 1a of the second light guide plate 1 travels in the direction opposite to the arrow in FIG. The light is received by the phototransistor 9 arranged therein. Further, the light diffusion layer 6 is
Although the light guide plate 1 is provided on the lower surface of the light guide plate 1, it may be provided at the same position on the upper surface of the reinforcing plate 7.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings; for example, spacers,
Various modifications can be made without departing from the spirit of the invention, such as the second plate-like member may be made into other shapes.

[Effect of idea]

According to the present invention, as is clear from the above explanation, although it is a non-contact type switch device that uses a light emitting element and a light receiving element, it is possible to reduce the cost and simplify the structure, and also to reduce the overall cost. This has the beneficial effect of promoting miniaturization and thinning, and furthermore, achieving a dramatic improvement in productivity.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a longitudinal sectional view, FIG. 2 is an exploded perspective view of the main parts, and FIG. 3 is a longitudinal sectional view in a different state from FIG. 1. In the figure, 1 is a first light guide plate (first plate-like member),
2 is a spacer, 3 is a second light guide plate (second plate-shaped member), 3a is a light projection part (opening), 4 is a light shielding film, 5 is a light reflection layer, 6 is a light diffusion layer, 7 is a reinforcement board,
Reference numeral 8 indicates a light emitting diode (light emitting element), and reference numeral 9 indicates a phototransistor (light receiving element).

Claims (1)

[Scope of utility model registration request] A first plate-like member having a light-guiding property, and a structure in which the first plate-like member is arranged in an overlapping manner with a spacer interposed therebetween, and there is a space between the first plate-like member and the first plate-like member. a second plate-like member that is arranged in parallel and has an opening that corresponds to the cavity, and is made of a light-guiding material and has substantially the same optical refractive index as the first plate-like member; , an elastically deformable light reflecting layer provided on the upper surface of the second plate member so as to correspond to at least the opening;
a light diffusion layer formed on the lower surface of the plate-like member so as to correspond to at least the opening; and a light projection arranged to project light into the first plate-like member or the second plate-like member. and a light-receiving element that is arranged to receive light from the second plate-like member or inside the second plate-like member and generates a switching signal in a light-receiving state.