Low-profile illuminated switch assembly

The present invention relates to an illuminated switch assembly that includes a case; a circuit board disposed inside the case; a light-emitting diode mounted on the circuit board to emit light downward; a light-guiding member configured to transmit the light emitted downward by the light-emitting diode to a position above the circuit board; and an operation member disposed in an upper part of the case to be operable as a switch, the operation member being configured to be illuminated with light received from the light-guiding member.

CLAIM OF PRIORITY

This application claims benefit of Korean Patent Application No. 2012-0021301 filed on Feb. 29, 2012, which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an illuminated switch assembly. In particular, the present invention relates to a low-profile illuminated switch assembly.

2. Description of the Related Art

Generally, a vehicle has various control switches in front of the driver's seat to control additional functions of the vehicle. Types of such control switches that have been mainly used include a lever type, a push-button type, and a rotary type. As an air-conditioner control switch, a control switch of combined type having both push and rotary functions has been often used particularly in recent years.

When a vehicle having such a combined-type switch drives at night, an illumination structure is used in which when the vehicle's interior lighting is turned on, light is emitted by an internal LED for illumination and passes through a lens for illumination to reach a push button, so that a symbol printed on the push button is illuminated with the light.

Korean Patent No. 0721236 discloses a technique related to a two-point illuminated rotary switch.

The related art described above provides a combined-type rotary switch mounted to a connector terminal of an audiovisual (AV) electric device and configured to emit an operation signal by being pressed or rotated. The combined-type rotary switch includes a rotary switch housing connected to the connector terminal; a switch knob made of transparent material, and inserted in the rotary switch housing to support components sequentially fitted therein; a serration lens fitted in the switch knob, and having serrations formed at a light incident portion and a rim to allow light from many LEDs serving as light sources to travel in straight lines and bend; a transparent lens made of transparent material and configured to surround the rotary switch housing; a handle made of translucent material, and having the transparent lens inserted therein to be illuminated through the transparent lens; and a push button fitted in the handle and configured to move the switch knob, when pressed, to operate a switch on a printed circuit board (PCB) having the LEDs mounted thereon.

In the related art described above, it is inevitable to use a double-sided mounting structure in which components are mounted on the lower side of the PCB and LEDs are mounted on the upper side of the PCB. The double-sided mounting structure is inconvenient in that it makes the design process complicated, inevitably requires development of a program for driving the PCB, and involves an enormous cost.

Also in the related art, it is necessary to secure a large separation space between components to avoid interference with the LEDs mounted on the upper side of the PCB. The space usability is thus degraded, and the related art cannot be applied if the separation space between the PCB and components disposed above the PCB is narrow.

SUMMARY OF THE INVENTION

The present invention solves the problems of the related art by providing an illuminated switch assembly in which light from an LED mounted on a circuit board to emit light downward is refracted horizontally and vertically to reach a position above the circuit board, and thus a space above the circuit board can be used, a plurality of illuminated regions can be simultaneously illuminated with light from the single LED, and the brightness of the plurality of illuminated regions connected to the LED can be simultaneously adjusted by adjusting the brightness of the LED.

The present invention provides an illuminated switch assembly including a case; a circuit board disposed inside the case; an LED mounted on the circuit board to emit light downward; a light-guiding member configured to transmit the light emitted downward by the LED to a position above the circuit board; and an operation member disposed in an upper part of the case to be operable as a switch, the operation member being configured to be illuminated with light received from the light-guiding member.

The circuit board may be disposed with the mounting surface thereof facing downward. The operation member may have a symbol illuminated portion.

The circuit board may have at least one through hole, through which the light-guiding member may extend from below to above the circuit board.

The light-guiding member may include a light input portion that faces the LED to receive light from the LED; and a light branching portion that extends from the light input portion, bends to extend horizontally, and further bends to extend vertically.

More than one light branching portion may be connected to the light input portion.

A switch contact portion of the operation member may be located between the circuit board and the operation member; and an elastic member may be disposed between the circuit board and the switch contact portion.

According to the present invention, it is possible to mount an LED on the circuit board such that the LED emits light downward, realize a compact layout of the illuminated switch assembly, and use a space above the circuit board. Even if a separation distance between the circuit board and a component (such as the operation member) disposed above the circuit board is narrow, the illuminated switch assembly of the present invention can be provided.

The problems of the related art can be solved when the lower surface of the circuit board serves as the mounting surface. Additionally, a plurality of illuminated regions can be illuminated with light from the single LED. The brightness of the plurality of illuminated regions (symbol illuminated portions) connected to the single LED can be simultaneously adjusted by simply adjusting the brightness of the LED. It is thus possible to provide the effect of simplifying the circuit management.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1is a cross-sectional view illustrating a structure of an illuminated switch assembly according to the present invention.

As illustrated inFIG. 1, the illuminated switch assembly according to the present invention mainly includes a case110, a circuit board120, an LED123, a light-guiding member130, and an operation member140.

The operation member140is, for example, a switch member including a switch knob. To allow the user to operate even in dark places, the operation member140is configured to be illuminated with light emitted from the LED123. The operation member140illustrated inFIG. 1is a switch member for operating a power window of a vehicle door. The operation member140ofFIG. 1is configured such that when the user presses the switch knob, a switch contact portion160performs a switching operation to give an operation signal to a control circuit (not shown) on the circuit board120, and thereby drives a motor (not shown) for opening or closing the vehicle window. The present specification does not describe in detail the configuration of the operation member140, as various embodiments of the operation member140may be made by those skilled in the art. Types of the operation member140that can be used include, but are not limited to, a lever type, a push-button type, a rotary type, and a combined type having both push and rotary functions. The illuminated switch assembly of the present invention is applicable regardless of the type of the operation member140, as long as the operation member140can be illuminated. The case110may be of either independent type or attached type, such as a switch box for a vehicle.

The circuit board120may be disposed inside the case110, with the mounting surface thereof facing downward.

In the present specification, the term “upper” or “upward” refers to the position or direction in which the operation member140is disposed in the illuminated switch assembly, and the term “lower” or “downward” refers to the position or direction opposite that in which the operation member140is disposed.

The circuit board120may be a single-sided mounting board instead of, for example, a double-sided mounting board. The circuit board120may be disposed with the mounting surface thereof facing downward.

For example, a PCB or a printed wiring board (PWB) may be used as the circuit board120.

The PCB refers to one that is obtained by placing and soldering components, such as a resistor, a capacitor, a coil, a transistor (TR), an integrated circuit (IC), a large-scale integrated circuit (LSI), and a switch, onto a PWB to complete a circuit function. The PWB refers to one that is obtained by forming a wiring pattern of copper foil on a copper clad laminate by, for example, etching. The wiring pattern is based on circuit design and represents electrical wiring that connects circuit components. The PWB is provided with both wiring and components mounted thereon.

The LED123is mounted on the circuit board120. The LED123is mounted, together with electrical components, on the lower surface of the circuit board120. Light from the single LED123is transmitted through the light-guiding member130to a position above the circuit board120.

The light-guiding member130is disposed to face the LED123.

The light-guiding member130receives light emitted from the LED123and transmits the light to a position above the circuit board120. The light-guiding member130may be configured to have a substantially U shape with one shorter leg, as viewed from one side.

A type of optical waveguide configured to be capable of efficiently transmitting optical signals is used as the light-guiding member130. For example, the light-guiding member130may be made of quartz. As illustrated inFIG. 1, light emitted from the LED123travels while being refracted and/or reflected inside the light-guiding member130to form a plurality of optical paths135. The optical paths135illustrated inFIG. 1are merely an example. Other optical paths not shown inFIG. 1, or different from those inFIG. 1, may be formed inside the light-guiding member130.

FIG. 2is a perspective view illustrating a first embodiment of the light-guiding member130according to the present invention.FIG. 3is a perspective view illustrating a second embodiment of the light-guiding member130according to the present invention.

Referring toFIG. 2andFIG. 3, the light-guiding member130may include a light input portion131and a light branching portion133. The light input portion131faces the LED123to receive light from the LED123. The light branching portion133extends from the light input portion131, bends to extend horizontally, and further bends to extend vertically.

As illustrated inFIG. 2andFIG. 3, a plurality of light branching portions133may be connected to the light input portion131to provide a plurality of illuminated regions.

FIG. 2illustrates an example where the light branching portions133are disposed on both sides of the light input portion131.FIG. 3illustrates an example where the light branching portions133are disposed in four directions around the light input portion131. More than four light branching portions133may be disposed around the light input portion131.

The light branching portions133are configured to bend to extend upward. The circuit board120may have a through hole121, through which the light-guiding member130may extend from below to above the circuit board120.

The operation member140operable as a switch is disposed in an upper part of the case110.

The operation member140may have a symbol illuminated portion141illuminated with light received from the light-guiding member130. The symbol illuminated portion141presents a symbol that allows the user to intuitively recognize the operation of the operation member140. For example, if the operation member140includes a switch knob for operating a power window, upward and downward arrows indicating upward and downward operations of the power window can be presented by the symbol illuminated portion141. The symbol illuminated portion141may be configured in various embodiments. For example, the symbol illuminated portion141may be made of transparent material that simply allows transmission of light from the LED123, or may be made of material that allows transmission of light from the LED123while varying the color of the light.

The switch contact portion160may be disposed between the circuit board120and the operation member140to emit a contact signal in response to the operation of the operation member140.

An elastic member150may be disposed between the circuit board120and the switch contact portion160to elastically support the switch contact portion160. The elastic member150is made of elastic material, such as rubber or urethane resin. The material of the elastic member150is not particularly limited, as long as the elastic member150can elastically support the switch contact portion160.

During operation of the operation member140, the elastic member150elastically supports the switch contact portion160to provide a restoring force. The operational feeling of the operation member140can thus be improved.

FIG. 4is a plan view illustrating an example where the illuminated switch assembly according to the present invention is applied to a vehicle window switch. As illustrated, the illuminated switch assembly of the present invention can be effectively used in a structure, such as a vehicle window switch, that includes a plurality of operation members140.

In the present invention having the configuration described above, the LED123and the light-guiding member130are disposed below the circuit board120. It is thus possible to reduce the space between the circuit board120and the operation member140. Also, since the circuit board120can be configured as a single-sided mounting board instead of a double-sided mounting board, it is possible to solve the problems of design constraints in the double-sided mounting board of the related art.

Additionally, since a plurality of symbol illuminated portions141of the operation members140can be illuminated with light from the single LED123, the unit price of the illuminated switch assembly can be reduced. The brightness of a plurality of illuminated regions (symbol illuminated portions141) connected to the single LED123can be simultaneously adjusted by adjusting the brightness of the LED123. This is advantageous in that the circuit management can be simplified.

Embodiments of the present invention have been described with reference to the attached drawings. It should be understood by those having ordinary knowledge in the technical field of the present invention that the present invention can be carried out in other specific forms without changing its technical idea or essential features. For example, by changing the material or size of each component part in accordance with the field of application, or by appropriately combining or replacing the embodiments, those skilled in the art can carry out the present invention in forms not specifically disclosed in the embodiments of the present invention, again, without departing from the scope of the present invention. Therefore, the embodiments described above are illustrative in any sense and should not be understood as being restrictive. Such modified embodiments should be considered as being within the scope of the technical idea described in the claims of the present invention.