JP2001155573A - Switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light transmission switch having good waterproofing and dust-proofing property, reducing the number of parts for saving, man-hours in molding and assembling. SOLUTION: The switch comprises a printed-circuit board 1 on which a switch for input 10 is mounted, a housing 2 containing the printed-circuit board 1, an elastic cover 4 with which the printed-circuit board 1 is covered, a key top 3 to push the switch 10 via the cover 4, and a switch cover 12 for enveloping. The elastic cover 4, consisting of a fitting part 5 to the key top 3, an outer frame 7 having close contact with the housing 2, and an elastic part 6 closely connecting the part 5 and the frame 7, is molded in one body by a molding method using varied material molding method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof and dustproof switch used in various control input devices and vending machines.

[0002]

2. Description of the Related Art As shown in FIG. 11, switches used in various control input devices, vending machines and the like include:
A switch including a printed circuit board 90 on which an input switch 95 is mounted, a housing 91 arranged so as to surround the printed circuit board 90, and a key top 92 for pressing the switch is used. Such switches can be used alone, or a plurality of switches can be arranged in series, or an appropriate number of switches can be arranged vertically and horizontally according to the purpose of use of the control input device or vending machine. Have been.

Some of these control input devices and vending machines are used outdoors, and they are waterproof and dustproof so that rain and dust do not enter the inside and cause malfunction of the switch. Some measures have been taken. In particular, when rain or dust comes in contact with the printed circuit board 90 on which the switch is mounted,
Corrosion of metal parts of components mounted on the printed circuit board 90 and obstruction of movement of the operation section of the input switch 95 may cause malfunction.

In a conventional switch, the periphery of a printed circuit board 90 is covered by a board cover 93 formed of soft rubber or elastomer, and a cover outer frame 94 formed by injection molding using a hard resin is provided on the housing 9 from outside the board cover 93.
1 and a board cover 93
To prevent rain and dust from coming into contact with the printed circuit board 90 to provide waterproofing and dustproofing. As the key top 92 to be pressed at the time of input, a key top molded by injection molding using a hard resin is used, and is fitted to an elastic substrate cover 93.

[0005] Since a soft rubber or elastomer is used as a molding material of the substrate cover 93, the close contact between the substrate cover 93 and the housing 91 is improved, and the key top 92 is formed.
Is pressed, the board cover 93 bends and the input switch 9
When the key top 92 is released and the key top 92 is released, the bending is returned by elasticity, so that the board cover 93 can return to the original state. The switch assembled in this manner is covered with a switch cover 97 having a hole for projecting the key top 92 from the outside, and is used in various control devices and vending machines.

A light source such as a light emitting diode 96 is mounted on the printed circuit board 90 so that the user can easily confirm that the user has made an input. There is an illuminated switch that emits light to improve visibility. In such an illuminated switch, it is necessary to guide the light emitted from the light source to the outside, and therefore, a substrate cover 93 formed of a light-transmitting material is used. The light emitted from the light source passes through a light-transmitting substrate cover 93, and passes through a key top 92 formed of a transparent resin or a resin having a light transmitting property so that the user can visually recognize the key top 92. ing.

In the conventional method using the substrate cover 93 for the purpose of waterproofing and dustproofing, the substrate cover 93 is brought into close contact with the substrate cover 93 formed of soft rubber or elastomer and the housing 91 formed by injection molding using hard resin. Molding is troublesome because each of these needs to be formed using a different method or a different molding machine. Further, since the board cover 93 and the cover outer frame 94 formed by different methods have to be fitted in the assembling process, the assembling is troublesome.

When a light source such as a light-emitting diode 96 is mounted on a printed circuit board 90 on which an input switch 95 is mounted, the light source emits light when the switch is input and is used as an illuminated switch for improving visibility. The substrate cover 93 formed of soft rubber or elastomer which covers the printed circuit board 90 so as not to hinder the transmission of light is required to have excellent light transmittance such as transparent or nearly transparent. However, none of the soft rubbers and elastomers used for molding the substrate cover 93 have an excellent light transmittance such as transparent or nearly transparent. For example, a commonly used silicone resin is milky white. Therefore, there is a disadvantage that the light emitted from the light source is greatly attenuated.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an excellent waterproof and dustproof property, to reduce the number of parts, to save the trouble of molding or assembling parts, and to reduce the light transmittance. Another object of the present invention is to provide a switch having good visibility for good.

[0010]

According to the first aspect of the present invention, there is provided a printed circuit board on which an input switch is mounted, a housing on which the printed circuit board is installed, and a printed circuit board. Elastic cover 4 to be covered, and key top 3 for pressing switch 10 through elastic cover 4
And a switch cover 12 covering the outside, a switch is formed, a fitting portion 5 for fitting the key top 3, an outer frame portion 7 in close contact with the housing 2, the fitting portion 5 and the outer frame portion 7. And an elastic cover 4 composed of an elastic portion 6 having elasticity that connects them.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the invention, the elastic cover 4 is formed by a different material forming method, and a hard heat is formed in the first forming of the different material forming method. Fitting part 5 and outer frame part 7 made of plastic resin
In the secondary molding, an elastic part 6 is injection-molded with a thermoplastic elastomer having elasticity.
The outer frame 7 and the elastic part 6 are integrated during the molding process.

In the switch according to the third aspect of the present invention, the switch according to the first aspect is provided.
Alternatively, in addition to the configuration of the invention of claim 2, a compression surface 9 formed by extending the elastic portion 6 formed of a thermoplastic elastomer is provided on the surface of the outer frame portion 7 of the elastic cover 4 which is in close contact with the housing 2, When the elastic cover 4 and the housing 2 are brought into close contact with each other, the compression surface 9 of the elastic portion 6 and the housing 2 are brought into close contact with each other.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram illustrating an example of a switch according to the present invention separately for each component, and illustrates a printed circuit board 1 on which an input switch 10 is mounted.
And an elastic cover 4, a key top 3, and a housing 2 for accommodating those parts, and a switch cover 1 for covering the outside.
2. A light emitting diode 11 mounted on the printed circuit board 1 as required, a cable 13 for connecting the printed circuit board 1 to an external controller, and a screw 14 for fixing the housing 2 and the switch cover 12 together. It is configured as a part.

The key top 3, the housing 2, and the switch cover 12 are each formed by a known injection molding method using a hard thermoplastic resin represented by an ABS resin, a polystyrene resin, a polycarbonate resin, a polymethyl methacrylate resin, or the like. You. FIG. 2 is a partial cutaway view showing an example of the elastic cover.
The outer frame portion 16, the elastic portion 17, a projection 18 for pressing an input switch extended from the elastic portion 17, and a compression surface 19 extended to a position corresponding to the back surface of the outer frame portion 16, and each of the fitting portions 15, the elastic portion 6, the projection 18 for pressing the switch extended from the elastic portion 6, and the compression surface 19 are integrally formed as one part at the time of molding.

FIGS. 3, 4, 5 and 6 show an example of an injection molding method for an elastic cover. Such an injection molding method is generally called a different material molding method or a two-color molding method. ing. FIG. 3 is a diagram showing the primary molding of the dissimilar material molding method, in which the lower mold 20 and the upper mold 21 are closed, and is a space filled with resin during injection molding. Resin filling space 22 for molding the second fitting portion 15
And a resin filling space 23 for molding the outer frame 16. The resin for molding is filled into the resin filling space 22 and the resin filling space 23 from the injection port 24 through the resin flow path 25 by a known injection molding machine.
And the outer frame portion 16 is formed.

The resin used for the primary molding is AB
There is a hard thermoplastic resin represented by S resin, polystyrene resin, polycarbonate resin, polymethyl methacrylate resin and the like. FIG. 4 is a diagram in which the upper mold 21 of the primary molding is separated from the lower mold 20 after the filling of the resin is completed by the primary molding, and the fitting portion 26 of the elastic cover molded by the primary molding and the outer frame portion. 27 remains in the lower mold 20 without being separated.

FIG. 5 is a view showing the secondary molding of the dissimilar material molding method, in which the lower mold 20 and the secondary mold upper mold 28 which is replaced with the primary mold upper mold 21 are closed, and the injection molding is performed. In order to form a portion corresponding to the elastic portion 17 of the elastic cover shown in FIG. 2, a projection 18 for pressing a switch extended from the elastic portion 17 and a compression surface 19, the space is filled with resin. The resin filling space 31 is provided. The resin for molding is filled into the resin filling space 31 from the injection port 29 through the resin flow path 31 by a known injection molding machine.

In the secondary molding, the resin melted at a high temperature is filled into the resin filling space 31 at a high pressure, so that the contact surface with the fitting portion 26 formed by the primary molding and the outer frame are formed. Part 2
Are welded to each other on the contact surface with the metal 7 and integrated. As the resin used for the secondary molding, a thermoplastic elastomer having elasticity is used. In particular, thermoplastic elastomers of urethane-based elastomer, polyester-based elastomer, and polystyrene-based elastomer have excellent moldability and weldability or excellent elasticity. It is preferable from having.

FIG. 6 is a view showing a state in which the upper mold 28 of the secondary molding is separated after the completion of the secondary molding, and the protrusion pin 35 is moved to separate the elastic cover from the lower mold 20. Constituent part 26, elastic part 32, elastic part 3 to constitute
The protrusion 33 for pressing the switch extended from 2, the compressed surface 34 extended to a position corresponding to the back of the outer frame 27, and the respective portions of the outer frame 27 are welded to each other at their contact surfaces during molding. Therefore, it does not peel off after being separated from the lower mold 20.

A typical example of the arrangement when assembling the components that have been formed in this way will be described with reference to FIG. The printed circuit board 1 on which the input switch 10 is mounted is mounted on a housing 2, and an elastic cover 4 is arranged so as to cover the printed circuit board 1. At this time, for example, when a cable for transmitting an input signal when the input switch 10 of the printed circuit board 1 is input to the outside is required, the cable 13 is used.
Is mounted on the printed circuit board 1 by a connector or the like, and is connected to a power supply, a controller, or the like disposed outside through a hole provided in a part of the housing 2.

The key top 3 for pressing and inputting the input switch 10 is fitted and fitted to the fitting portion 5 of the elastic cover 4, and the switch cover 12 provided with a hole for protruding the key top 3 from the outside thereof is mounted. , Screw 1
4, the housing 2 and the switch cover 12 are screwed.

FIG. 7 is a sectional view of an example showing an assembled state of the switch according to the present invention. The printed circuit board 37 on which the input switch 38 is mounted is arranged at a predetermined position of the housing 36, and the fitting portion 40, the outer frame portion 41, the elastic portion 43, and the switch extended from the elastic portion 43 are pressed so as to cover the periphery thereof. An elastic cover comprising a compression surface 45 extending to a position corresponding to the rear surface of the outer frame portion 41 and a projection 44 for disposing the switch is provided. It is arranged so as to be at a position facing the mounted input switch 38. The outer frame 41 is provided with a rib 42 extending from the outer frame 41 at a position where the rib 42 is in contact with a rib 47 provided inside the switch cover 46 during assembly.

There are various methods for determining the position of the elastic cover and the housing 36. In the example of FIG. 7, the printed board 37 is placed on a printed board supporting rib 48 extending from the housing 36, and The positioning hole 5 penetrating through the compressed surface 45 extending from the outer frame portion 41 and the elastic portion 43 of the elastic cover is provided in the cylindrical positioning protrusion 49 provided.
The position is decided by inserting 0. Further, inside the elastic cover, a board holding rib 51 extending from the outer frame portion 41 and the elastic portion 37 is provided at a position to sandwich the printed circuit board 37 when the positions of the elastic cover and the housing 36 are determined.

When the elastic cover and the housing 36 are combined, the printed board 37 is sandwiched between a printed board supporting rib 48 and a surface having elasticity, which is a part of the elastic portion 43 of the board holding rib 51, from a predetermined position. There is no deviation. A key top 52 having a recess 53 with an inner diameter that is forcibly fitted and fitted with the fitting portion 40 of the elastic cover is fitted into the fitting portion 40 of the elastic cover.

On the key top 52, characters, numerals, symbols, and the like to be displayed in advance can be displayed by printing or engraving. As another method, it is possible to use a key top 52 which is formed by using different colored resins for characters, numerals and symbols to be displayed and other portions. Such a key top using two kinds of resins having different colors can be molded by a known dissimilar material molding method.

As a method of fitting the key tops, in addition to the above-described method, a projection is provided on the outer periphery of the fitting portion 40 or inside the recess 53 of the key top 52, and a depression is provided at a position corresponding to the projection. As shown in the method of fitting the respective protrusions and depressions, and the partial cross-sectional view of the elastic cover in FIG.
When the joint portion 59 between the elastic cover elastic portion 58 and the fitting portion 57 is set larger than the fitting portion 57 so as to be forcibly fitted into the concave portion 61 of the inner diameter of the key top 60, and the key top 60 is fitted. There is a method in which a part of the joint 59 is compressed and the key top 60 is held by the repulsive force.

A switch cover 46 having a through hole through which the key top 52 passes is fixed in accordance with the housing 36. At this time, a rib 47 provided inside the switch cover 46 extends from the outer frame portion 41 of the elastic cover. The elastic cover is pressed in the direction of the housing 36 by contact with the ribs 42 thus formed, so that the elastic cover is brought into close contact with the contact surface between the compression surface 45 of the elastic cover and the housing 36, and the printed board 37 is
And the elastic cover can be hermetically sealed.

At this time, the compression surface 45 of the elastic cover formed of a thermoplastic elastomer having elasticity is compressed by being pressed against the housing 36 to enhance the effect of close contact and to obtain a sufficient sealing. . Although the compression surface 45 of the elastic cover is a flat surface in the example of FIG. 7, a projection surrounding the outer frame portion 41 is provided on the compression surface 45 in addition to the flat surface, and the elastic cover is pressed toward the housing 36. At this time, if the projections are compressed, the sealing effect can be further enhanced. FIG. 9 is a partial cross-sectional view showing an elastic cover provided with such protrusions. The protrusions protruding from the periphery of the outer frame portion 62 by extending a part of the elastic portion 64 formed integrally with the outer frame portion 62. This is an example in which a unit 65 is provided.

When the housing 66 and the switch cover 67 are combined, a rib 68 provided inside the switch cover 67 is provided.
Comes into contact with the rib 63 extending from the outer frame portion 62 of the elastic cover and presses the elastic cover in the direction of the housing 66, so that the elastic projection 65 of the elastic cover
6, the printed circuit board 69 can be sealed in the space between the housing 66 and the elastic cover.

There are various methods for aligning the switch cover 46 with the housing 36. In the example shown in FIG. 7, the screw holes provided in the switch cover 46 and the through holes of the screws provided in the housing 36 are aligned, and the resin Tapping screw 54
The screw is passed through the through hole of the housing 36 and screwed into the screw hole of the switch cover 46.

Some of the switches allow the user to easily confirm that the input has been made,
Alternatively, a light source such as a light emitting diode 39 is mounted on the printed circuit board 37 so that the user can recognize the position and function of the switch when used in a dark place such as at night, and when the input switch 38 is turned on or at night. When the switch is used in a dark place, the light source emits light to improve the visibility of the switch. In the case of such an illuminated switch, since light emitted from a light source such as the light emitting diode 39 needs to pass through the fitting portion 40 and the key top 52, the fitting portion 40 of the elastic cover and the outer frame portion are required. When molding 41, it is molded using a resin having a light transmitting property, and the key top 52 is similarly formed using a resin having a light transmitting property.

As such a resin having a light transmitting property, a polycarbonate resin, a polymethyl methacrylate resin, a polyacetal resin, or the like, which is transparent or colored so as not to completely impair the light transmitting property, is used. When it is necessary to display characters, numbers, symbols, and the like on the key top 52, print the characters, numbers, and symbols to be displayed on the key top 52 with light-shielding paint, or, on the contrary, the characters and numbers that you want to display. There is also a type in which light other than characters, numerals, and symbols that are desired to be printed and displayed other than symbols is transmitted.

There is also a method of sandwiching a light-transmitting sheet between the key top 52 and the fitting portion 40. For example, characters, numerals, and symbols to be displayed are printed on a light-transmitting resin sheet. Or a printed version of the other part, excluding the characters, numbers and symbols to be displayed. As another display method, it is also possible to use a key top 52 formed by using two kinds of resins having different light transmittances on the display part such as letters, numbers and symbols and the other part. .

For example, the display portion of the key top 52 such as letters, numbers, and symbols is formed of a light-transmitting resin, and the other portions are formed of a resin having a light-shielding property by adding a pigment or the like to emit light. Light emitted from a light source such as a diode 39 transmits only characters such as letters, numbers, and symbols formed of a light-transmitting resin and emits light, and conversely, letters, numbers, and symbols of a key top 52. Are molded with a resin having a light shielding property by adding a pigment or the like, and the other parts are molded with a light-transmitting resin.
Light emitted from a light source such as No. 9 only emits light by transmitting through other portions formed of a light-transmitting resin. Such a key top 52 using two kinds of resins having different light transmittances can be molded by a known dissimilar material molding method.

The switch assembled as described above is used by being attached to a control input device or a vending machine. However, in addition to being used alone, the switch can be used in accordance with the control input device or the vending machine. Multiple switches can be arranged in series,
Alternatively, an appropriate number can be arranged vertically and horizontally for use. When a plurality of switches are used, the switch cover 46 having a hole through which the housing 36 and the required number of key tops 52 are extended is extended according to the size of the input device for control or the vending machine. The housing 36 and the switch cover 46 can be used as a control input device or a housing of a vending machine. Further, the printed circuit board 37 is extended according to a control input device, a vending machine, or the like, and one printed circuit board 37 is provided.
A plurality of light sources, such as a plurality of input switches 38 and light-emitting diodes 35, may be used.

[0036]

According to the switch of the present invention, instead of a board cover formed of a soft rubber or elastomer for the purpose of waterproofing and dust-proofing as in the case of a conventional switch, it includes peripheral parts required for assembling the switch. By integrally molding, the number of molding steps can be reduced, and the cost required for molding can be reduced. Further, since the switch can be assembled with a smaller number of parts than the conventional switch, the assembling operation can be facilitated, and the assembling can be performed in a short time and at a low cost. In addition, when used as an illuminated switch, it can increase the light transmission compared to conventional switches, and has excellent visibility when used in various control input devices and vending machines. This makes it possible to provide a switch that is easy to use even for the user.

[0037]

Embodiment 1 FIG. 7 is a sectional view of a switch assembled according to the present embodiment. A printed board 37 on which an input switch 38 and a light emitting diode 39 are mounted is disposed on a printed board supporting rib 48 which is a part of the housing 36 formed by a known injection molding method using an ABS resin. The light emitting diode 39 mounted on the printed circuit board 37 is configured to emit light when the input switch 38 is input. A cable 55 is attached to the printed circuit board 37 by a connector 56 in order to supply electric power to the printed circuit board 37 from the outside or to transmit an input signal of the input switch 38 to the outside, and a switch is provided through a hole provided in a part of the housing 36. It is connected to a power supply and a controller arranged outside the device.

The fitting portion 40, the outer frame portion 41 and the elastic portion 43, the projection 44 for pushing a switch extended from the elastic portion 43, and the outer frame portion so as to cover the periphery of the printed circuit board 37 thus arranged. An elastic cover comprising a compression surface 45 extended to a position corresponding to the back surface of 41 is disposed. In arranging the elastic cover, the projection 44 for pressing the switch is arranged so as to face the input switch 38 mounted on the printed circuit board 37.

Next, an elastic cover comprising a fitting portion 40, an outer frame portion 41 and an elastic portion 43, a projection 44 for pushing a switch extended from the elastic portion 43, and a compression surface 45 by the above-described dissimilar material molding method. The molding method will be described with reference to FIGS. 3, 4, 5, and 6. FIG. 3 is a diagram showing the primary molding of the dissimilar material molding method, in which the lower mold 20 and the upper mold 21 are closed, and is a space filled with resin during injection molding. A resin filling space 22 and a resin filling space 23 for molding the fitting portion 40 and the outer frame portion 41 are provided. As the resin used for the primary molding, a transparent polycarbonate resin having a light transmitting property was used.

Using a well-known injection molding machine, the resin filling space 22 and the resin filling space 23 are filled with the polycarbonate resin from the injection port 24 through the resin flow path 25, and the fitting portion 40 shown in FIG. A portion corresponding to the outer frame portion 41 was formed. FIG. 4 shows the lower mold 2 after the filling of the resin is completed by the primary molding.
FIG. 8 is a view in which the upper mold 21 of the primary molding is separated from 0, and the fitting part 26 and the outer frame part 27 corresponding to the fitting part 40 and the outer frame part 41 of FIG. It remains in the lower mold 20 without being separated.

FIG. 5 is a view showing the secondary molding of the dissimilar material molding method, in which the lower mold 20 and the upper secondary mold 28 replaced with the upper primary mold 21 are closed, and the injection molding is performed. In this case, there is provided an elastic portion 43 shown in FIG. 7, a protrusion 44 for pressing a switch extended from the elastic portion 43, and a resin filling space 31 for molding a compression surface 45. I have. As the resin used for the secondary molding, an urethane-based thermoplastic elastomer having elasticity was used.

Using a well-known injection molding machine, a resin-filled space 31 is filled with a urethane-based thermoplastic elastomer from an injection port 28 through a resin flow path 29, and the elastic portion 4 shown in FIG.
3. A portion corresponding to the protrusion 44 for pressing the switch extended from the elastic portion 43 and the compression surface 45 was formed. In this secondary molding, the urethane-based thermoplastic elastomer melted at a high temperature is filled into the resin filling space 31 at a high pressure, so that the fitting portion 26 and the outer frame portion 27 formed by the primary molding are used. Are welded to each other on the contact surface with the metal and integrated. FIG. 6 is a view showing a state in which the upper mold 28 of the secondary molding is separated after the completion of the secondary molding, and the protrusion pin 35 is moved to separate the elastic cover from the lower mold 20.

As shown in FIG. 7, the outer frame portion 41 is provided with a rib 42 extending from the outer frame portion 41 at a position in contact with a rib 47 provided inside the switch cover 46 during assembly. I have. When attaching the elastic cover and the printed board 37 to the housing 49, the printed board 37 is placed on a printed board supporting rib 48 extending from the housing 36, and the outer frame 41 and the elastic section 4 of the elastic cover are placed.
Positioning hole 50 penetrating compression surface 45 extended from 3
A cylindrical positioning projection 49 provided on the housing 36;
Is inserted, and the position is fixed.

A board holding rib 51 extending from the outer frame portion 41 and the elastic portion 43 is provided inside the elastic cover at a position sandwiching the printed board 37 when the position of the elastic cover and the housing 36 is determined. , Elastic cover and housing 3
When the number 6 is adjusted, the printed board 37 is not sandwiched between the printed board supporting ribs 48 and a surface having elasticity which is a part of the elastic portion 43 of the board holding rib 51 and does not deviate from a predetermined position. Since the fitting part 40, the elastic part 37, and the outer frame part 41 which constitute the elastic cover are integrated into one part, the work of attaching the elastic cover is extremely easy.

A key top 52 having a recess 53 with an inner diameter to be forcibly fitted and fitted with the fitting portion was fitted into the fitting portion 40 of the elastic cover. The key top 52 is formed by a known injection molding method using a transparent polycarbonate resin as a resin, and the surface of the recess 53 on the back side is provided with other parts except for letters, numbers, and symbols to be displayed in advance. It is printed with a light-shielding dark red paint so that light is transmitted only through the letters, numbers, and symbols to be displayed.

As a method of fitting the key top, as shown in a partial sectional view of FIG.
The joint portion 59 between the elastic portion 58 of the elastic cover and the fitting portion 57 is set to be larger than the fitting portion 57 so that the key top 60 is fitted. A part is compressed so that the key top 60 is held by the repulsive force.

The switch cover 46 having a hole through which the key top 52 passes is a cover that covers the outside of the switch and has an external appearance. The switch cover 46 is formed using an ABS resin as a resin by a known injection molding method. The positions of the screw holes provided in the switch cover 46 and the through holes of the screws provided in the housing 36 were aligned, and the screws 54 were screwed in to fix the switch cover 46 and the housing 36 by screws.

As described above, the switch cover 46 is fixed in accordance with the housing 36. At this time, the rib 47 provided inside the switch cover 46 is attached to the outer frame portion 41 of the elastic cover.
The elastic cover is pressed in the direction of the housing 36 by contacting the rib 42 extended from the housing 42, so that the elastic cover is brought into close contact with the elastic compression surface 45 and the contact surface of the housing 36,
The printed circuit board 37 can be sufficiently sealed in the space between the housing 36 and the elastic cover. Therefore, even when the device equipped with this switch is placed outdoors, rain or dust or the like, which may cause a malfunction of the switch, can be prevented from entering the printed circuit board 37.

In the switch thus assembled, when the key top 52 is pressed, the switch pressing projection 44 extending toward the input switch 38 on the back of the elastic cover presses the input switch 38, and the input signal is The data is sent to a controller arranged outside through a cable 55 attached to the printed circuit board 37 with a connector 56, and is used for controlling devices and the like. When the keytop 52 is pressed, the elastic portion 37 of the elastic cover formed of an elastic urethane-based thermoplastic elastomer is appropriately bent to facilitate input to the input switch 38. 52
Is released, the deflection returns to the original shape.

When the light is input to the input switch 38, the light emitting diode 39 mounted on the printed circuit board 37 is lit. The lit light passes through the fitting portion 40 of the elastic cover and the character to be displayed on the key top 52 is displayed. And the parts of numbers and symbols are made to emit light. At this time, the fitting part 40 and the key top 52
Is made of transparent polycarbonate resin,
The light emitted from the light emitting diode 39 can be easily applied to the fitting portion 4.
By transmitting the characters, numerals and symbols of 0 and the key top 52, excellent visibility could be obtained.

[0051]

Embodiment 2 The embodiment of FIG. 10 is a switch box for a controller used for a building machine such as a bulldozer used outdoors. The switch box is connected to an external controller by a cable 85, and the input of the switch box is performed. A signal when a switch is input is sent, and power is supplied to the printed circuit board 70 in the switch box. This switch box is required to be waterproof and dustproof for outdoor use, and it is required that the position and type of the key top of the switch be clearly visible to the user even in dark places such as at night. And a plurality of switches according to the present invention are arranged.

The housing 73 and the switch cover 83 constituting the switch box are formed by a known injection molding method using ABS resin. An input switch 71 corresponding to a plurality of key tops 80 and a light emitting diode 7 are provided on a printed circuit board 70 disposed inside a switch box at a predetermined position of a housing 73.
2 are mounted, and elastic covers 74 corresponding to the number are arranged so as to cover the input switch 71 and the light emitting diode 72. The light emitting diode 72 mounted on the printed circuit board 70 is configured to emit light when the input switch 71 is input or when the position of the switch is difficult to determine at night or the like.

The elastic cover 74 has a fitting portion 75 and an outer frame 76 formed of a transparent hard resin, an elastic portion 77 formed of an elastic thermoplastic elastomer, and an input extending from the elastic portion 77. It comprises a projection 78 for pressing the switch 71 and a compression surface 79 extending to a position corresponding to the back of the outer frame 76. Elastic cover 74
Is molded by the different material molding method described above,
The fitting portion 75 and the outer frame portion 76 are molded using a transparent polymethyl methacrylate resin in the primary molding of the different material molding method, and a polyester-based thermoplastic elastomer is used in the secondary molding of the different material molding method. Then, a projection 78 for pressing the elastic portion 77, the input switch 71 extended from the elastic portion 77, and a compression surface 79 extended from the elastic portion 77 to a position corresponding to the rear surface of the outer frame portion 76 were formed.

The fitting portion 75, the outer frame portion 76 and the elastic portion 7
7, a projection 78 extending from the elastic portion 77 for pressing the input switch 71, and a compression surface 79 extending from the elastic portion 77 to a position corresponding to the rear surface of the outer frame portion 76 are welded and integrated at their respective contact surfaces. It has become one of the parts.
Further, the fitting portion 75 is formed in such a size that it cannot be disengaged from the concave portion on the rear surface of the key top 80, and the key top 80 is fitted in the fitting portion 75.

The key top 80 is composed of a portion 81 representing a character or a symbol formed of a resin having a light transmitting property, and a cover 82 formed of a light shielding resin covering the periphery thereof. The key top 80 using two kinds of resins having different transmittances is molded by a known dissimilar material molding method. That is, in the primary molding of a different material molding method, a portion 81 representing a character or a symbol is molded using a light transmitting polyacetal resin, and then a black pigment is mixed in the secondary molding of a different material molding method. Cover part 8 using ABS resin with light shielding property
2 was molded. When the key top 80 is fitted into the fitting portion 75 of the elastic cover 74, the position is determined so that the portion 81 of the key top 80 representing the character or symbol corresponds to the light emitting diode 72 mounted on the substrate 80. I have.

Next, a switch cover 83 having a hole for projecting the key top 80 and formed by using a known injection molding method using an ABS resin is attached from the outside. At this time, the rib 84 provided inside the switch cover 83 comes into contact with the outer frame portion 76 of the elastic cover 74, and the compressed surface 79 is moved in the direction of the housing 73 while pressing the printed board 70 with a part of the compressed surface 79 of the elastic cover 74. , And the printed circuit board 70 is sealed by bringing the elastic cover 74 into close contact with the printed circuit board 70 and the housing 73. Since the fitting portion 75, the elastic portion 77, and the outer frame portion 76 constituting the elastic cover 74 are integrated into one component, the work of attaching the elastic cover 74 is extremely easy. . For example, even when the switch box is used outdoors, the printed circuit board 70 is connected to the elastic cover 74 and the housing 7.
3, so that rain, dust, and the like can be prevented from entering the printed circuit board 70, which may cause a malfunction of the switch.

In the switch thus assembled, when the key top 80 is pressed, the switch pressing projection 78 extending toward the input switch 71 on the back of the elastic cover presses the input switch 71, and the input signal is transmitted through the cable 85. It is sent to an externally placed controller and used to control equipment. When the key top 80 is pressed, the elastic portion 77 of the elastic cover formed of an elastic polyester-based thermoplastic elastomer is appropriately bent so that the input to the input switch 71 is facilitated. 8
When 0 is released, the bending returns to its original shape.

When the input switch 71 is turned on or when the position of the switch is difficult to determine at night or the like, the light emitting diode 72 mounted on the printed circuit board 70 is turned on. The portion 91 representing the character or symbol of the key top 80 is transmitted through the light source 75 to emit light. At this time, the fitting portion 75 is formed of a transparent polymethyl methacrylate resin, and the portions 91 of the key tops 80 representing characters and symbols are formed of a light-transmitting polyacetal resin. The light easily transmitted through the fitting portion 75 and the portion 91 of the key top 80 representing the characters and symbols, and excellent visibility was obtained.

[0059]

As described above, in the switch according to the present invention, as shown in FIG. 1, the elastic cover 4 which is in close contact with the housing 2 around the printed circuit board 1 on which the input switch 10 is mounted.
Is composed of an outer frame portion 7, a fitting portion 5, and an elastic portion 6. Since these components are integrally formed by a different material molding method, the number of components is smaller than that of a conventional switch. As a result, it is possible to easily produce an inexpensive switch without assembling or molding.

The elastic cover 4 is provided with a compression surface 9 extending from an elastic portion 6 formed of a thermoplastic elastomer on a surface of the outer frame portion 7 which is in close contact with the housing 2.
When the housing 2 is brought into close contact with the compression surface 9 of the elastic portion 6 and the housing 2, the printed circuit board 1 is excellent in hermeticity even when used outdoors, and has high waterproofness.
It has become possible to manufacture dustproof switches.

Further, according to the present invention, it is possible to mold the fitting portion 6 of the elastic cover 4 by using a resin having a high light transmission property. Even if it is used as an illuminated switch for lighting the light emitting diode 11 mounted on the printed circuit board 1 in a dark place, the fitting portion 6 of the elastic cover 4
By transmitting light satisfactorily, it became possible to manufacture a switch exhibiting excellent visibility.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a switch according to an embodiment of the present invention.

FIG. 2 is a perspective view in which a part of the switch is cut open.

FIG. 3 is a cross-sectional view showing a state in which a mold is closed by primary molding when an elastic cover incorporated in the switch is molded by a different material molding method.

FIG. 4 is a cross-sectional view showing a state where a mold is opened after the completion of the primary molding.

FIG. 5 is a cross-sectional view of a state in which a mold is closed in secondary molding of a different material molding method.

FIG. 6 is a cross-sectional view showing a state where a mold is opened after the completion of the secondary molding and an elastic cover is separated.

FIG. 7 is a sectional view of the switch in an assembled state.

FIG. 8 is an enlarged sectional view of a main part of the elastic cover.

FIG. 9 is an enlarged sectional view of a main part of the switch.

FIG. 10 is a perspective view of a switch according to another embodiment of the present invention, which is partially cut away.

FIG. 11 is an exploded perspective view of a conventional switch.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2 Housing 3 Key top 4 Elastic cover 5 Fitting part 6 Elastic part 7 Outer frame part 9 Compression surface 10 Input switch 11 Light emitting diode 12 Switch cover 13 Cable 36 Housing 37 Printed circuit board 38 Input switch 39 Light emitting diode 40 Fitting Part 41 Outer frame part 43 Elastic part 44 Switch pushing projection 45 Compression surface 46 Switch cover 52 Key top 55 Cable

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E044 AA01 CA01 EB06 FB02 FB14 5G006 AA01 AB01 AZ01 BA01 BB07 JA01 JB03 JC01 JD03 5G023 AA12 CA41 5G052 AA05 AA07 AA11 AA22 AA24 BB01 HA01 HA09 HA14 HA24

Claims (3)

[Claims] A printed circuit board on which an input switch is mounted, and a housing on which the printed circuit board is installed.
A switch comprising: an elastic cover 4 covering the printed circuit board 1; a key top 3 pressing the switch 10 via the elastic cover 4; and a switch cover 12 covering the outside.
An elastic cover 4 including a fitting portion 5 for fitting the key top 3, an outer frame portion 7 in close contact with the housing 2, and an elastic portion 6 having elasticity connecting the fitting portion 5 and the outer frame portion 7. A switch characterized by being integrally molded. 2. The elastic cover 4 is molded by a dissimilar material molding method. In the primary molding of the dissimilar material molding method, the fitting portion 5 and the outer frame portion 7 are injection-molded with a hard thermoplastic resin. The elastic part 6 is injection-molded by a thermoplastic elastomer having elasticity in the secondary molding, and the fitting part 5, the outer frame part 7, and the elastic part 6 are integrated in a molding process. Item 2. The switch according to Item 1. 3. The housing 2 of the outer frame 7 of the elastic cover 4.
A compression surface 9 is formed by extending an elastic portion 6 formed of a thermoplastic elastomer on a surface which is in close contact with the housing. When the elastic cover 4 and the housing 2 are brought into close contact with each other, the compression surface 9 of the elastic portion 6 and the housing 2 come into close contact with each other. The switch according to claim 1, wherein the switch is operated.