Switch assembly

A switch assembly comprises first and second tact switches located on a printed circuit board (PCB) at a predetermined interval, a shuttle body having a pair of tension ribs, including a first tension rib and a second tension rib located in parallel with each other, to turn on/off the first and the second tact switches, and a knob holding shaft provided between the first and the second tension ribs, a manipulation knob connected to the knob holding shaft of the shuttle body, rotating between a position where the manipulation knob presses one of the first and the second tension ribs to operate the corresponding tact switch and a position where the manipulation knob releases the tension rib, and a spring member connected with the knob holding shaft of the shuttle body elastically pressing the manipulation knob to the releasing position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(a) of Korean Patent Application No. 2003-52432, filed on Jul. 29, 2003, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a switch assembly. More particularly, the present invention relates to a switch assembly having a shuttle function and a button function in an integrated form.

2. Description of the Related Art

An electronic product, such as a video cassette tape recorder (VCR), a video tape recorder (VTR), or a digital video disk player (DVDP), is provided with a plurality of manipulation knobs to manipulate functions of the electronic product. The manipulation knobs are for various operations of, for example, playing, fast-forwarding, re-winding, pausing and stopping, according to the on/off state of the switches installed on a printed circuit board (PCB). However, because there are so many different manipulation knobs, the size of the product must be oversized. Recently, an integrated switch assembly has been developed to solve the problem by selectively manipulating a plurality of functions.

FIG. 1is a cross section view showing a conventional switch assembly, andFIG. 2is an exploded perspective view ofFIG. 1. As shown inFIGS. 1 and 2, a conventional switch assembly100includes a shuttle unit120and a plurality of tact switches131and132disposed on a printed circuit board (PCB)110, a shuttle knob140operating the shuttle unit120, and a button knob150for turning on/off the tact switches131and132. The conventional switch assembly100further includes a board holder160and a button knob holder170interposed between the tact switches131and132and the button knob150.

The plurality of tact switches131and132are arranged in a radial direction with respect to the shuttle unit120rotatably disposed on the PCB110. The plurality of tact switches131and132are located at predetermined intervals and signals the performance of different functions, namely, playing, stopping, pausing, or inserting/ejecting. The board holder160, located on the front surface of the PCB110, where the tact switches131and132are located, compensates for a stepped width between the tact switches131and132and the PCB110.

When assembled with the button knob holder170, the button knob150is connected to the front surface of the PCB110where the board holder160is disposed. The button knob holder170is provided with a plurality of poles171and172protruding therefrom and corresponding to the tact switches131and132fixed to the PCB110. As a side of the button knob150is pressed, the poles171and172of the button knob holder170turn on/off the corresponding tact switches131and132. The shuttle knob140is connected to the shuttle unit120to rotate 360° in either a clockwise direction or a counter-clockwise direction. The button knob150includes a plurality of tension ribs155spaced from the shuttle knob140by a predetermined distance. For example, a user can adjust the volume of sound by rotating the shuttle knob140.

However, the conventional switch assembly100has a complicated construction requiring assembly of the shuttle knob140, the button knob150, the button knob holder170, and the board holder160with the shuttle unit120. Therefore it is difficult to disassemble the switch assembly100, which increases manufacturing costs. Particularly, since the shuttle unit120is a single unit integrating a plurality of components therein, it has to be manufactured as an original equipment manufacturer (OEM) part, resulting in increased manufacturing costs.

Also, if a malfunction occurs in the relatively expensive shuttle unit120, the entire switch assembly100has to be replaced causing increased maintenance costs.

SUMMARY OF THE INVENTION

The present invention has been developed in order to solve the above problems in the related art. Accordingly, it is an aspect of the present invention to provide a switch assembly having a simplified construction capable of facilitating assembling/disassembling and, particularly, reducing manufacturing and maintenance costs.

Another aspect of the present invention is to provide a switch assembly with a compact design to reduce the size of a product.

Still another aspect of the present invention is to provide a switch assembly that makes operating an electronic product more convenient for a user.

The above aspects are achieved by providing a switch assembly comprising first and second tact switches disposed on a printed circuit board (PCB) at a predetermined interval. The switch assembly comprises a shuttle body having a pair of tension ribs including a first tension rib and a second tension rib located in parallel to each other, to turn on/off the first and the second tact switches; and a knob holding shaft between the first and the second tension ribs; a manipulation knob connected to the knob holding shaft of the shuttle body, rotating between a position where the manipulation knob presses one of the first and the second tension ribs to operate the corresponding tact switch and a position where the manipulation knob releases the tension rib. The switch assembly further includes a spring member connected to the knob holding shaft of the shuttle body to elastically press the manipulation knob to the releasing position.

The manipulation knob may comprise a pair of operating portions outwardly protruding from the manipulation knob in a radial direction, having a predetermined angle between each operating portion, and operating with the first and the second tension ribs of the shuttle body, and a connection portion extending from the manipulation knob in an axial direction and connected to the shuttle body.

In other embodiments, the first and the second tension ribs of the shuttle body each may comprise a protrusion upwardly protruding toward the manipulation knob, and an inclined portion formed at a predetermined inclination angle with respect to the protrusion and inwardly curved, contacting the operating portion of the manipulation knob.

In other embodiments, the shuttle body may have a guide hole or recess formed therein, to receive the connection portion of the manipulation knob and restrict the movements of the connection portion within a predetermined range.

In other embodiments, the operating portions of the manipulation knob each may include a pair of locking protrusions locked by opposite ends of the spring member, which exerts an elastic biasing force toward the releasing position.

In other embodiments, a third tact switch may be further disposed on the PCB, and the shuttle body further includes a third tension rib interposed between the first and the second tension rib to operate with the third tact switch, and the third tension rib is elastically deformed when pressed by the manipulation knob positioned at the release position, thereby turning on the third tact switch.

In other embodiments, the shuttle body may be provided with an elastic supporting rib which elastically supports the manipulation knob such that the third tension rib is placed at a position to turn off the third tact switch.

In other embodiments, the switch assembly may further comprise a shuttle ring interposed between the manipulation knob and a front panel of an electronic product which exposes a part of the manipulation knob to the outside.

In a preferred embodiment, the switch assembly further comprises a shuttle ring interposed between the manipulation knob and a front panel of an electronic product which exposes a part of the manipulation knob to the exterior of the electronic product.

The above aspects and other advantages are achieved by providing a switch assembly comprising a manipulation knob, and a shuttle body integrally formed with a knob holding shaft to which the manipulation knob is rotatably connected, and a plurality of tension ribs positioned within a rotating radius of the manipulation knob to be selectively deformed by the manipulation knob.

Furthermore, the switch assembly may further comprise a spring member connected to the knob holding shaft to return the manipulation knob to an original position.

In addition, the switch assembly may further comprise a plurality of tact switches fixed onto a printed circuit board (PCB) to be turned on/off by the plurality of tension ribs.

Finally, the shuttle body may be formed by injection molding.

In the drawing figures, it will be understood that like reference numerals refer to like features and structures.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT

Hereinafter, a switch assembly according to an exemplary embodiment of the present invention will be described in greater detail.

FIG. 3is a front view showing an electronic product having a switch assembly mounted therein according to an embodiment of the present invention,FIG. 4is a partially exploded perspective view ofFIG. 3,FIG. 5is an enlarged view of the part ‘A’ ofFIG. 4, andFIG. 6is a partial cross section view taken along the line V-V ofFIG. 3. As shown in these drawings, an electronic product1includes a case body (not shown) having an opening formed in a front portion thereof, and a front panel3blocking the opening of the case body. The case body has embedded a plurality of parts and a printed circuit board (PCB)11. A switching assembly17, tact switches21,22,23,24,25, and26, and display unit28are preferably located on the PCB11.

As shown inFIG. 3, a door4and a display window5are located in a center portion of the front panel3and located one above the other, and the door4vertically pivots to be opened and closed. For example, through the door4, a medium such as a video tape or a disk is inserted or ejected. The display window5is made of a transparent material to expose an operating state displayed on the display unit28to the outside. Functions keys6protrude through the display window5to perform functions of recording, adjusting a channel or adjusting a screen by turning on/off the respective tact switches26.

The front panel3is also provided with a power button13and an eject button14located on one side of the door4and the display window5. An external input unit15having a plurality of external input ports is preferably located under the power button13and the eject button14. Knob holes7,8, and9are formed in the front panel3on the side opposite the powerbutton13and the eject button14. The knob holes7,8, and9allow manipulation knobs71,84, and85, which form the switch assembly17, to protrude through the front panel3.

As shown inFIG. 4, the front panel3has a plurality of connection ribs10located at predetermined intervals along the length of the rear edge panel3. The connection ribs10include a connection hole or a hook. If the connection rib10has a connection hole, the connection ribs10are connected to the case body using an extra connection member (not shown). Meanwhile, if the connection rib10has a connection hook, the connection ribs10are connected to the case body using a hook hole formed in the case body.

Referring toFIGS. 4 and 5, the switch assembly17according to a preferred embodiment of the present invention includes the plurality of tact switches21,22,23,24,25, and26disposed on the PCB11, a shuttle body20to be mounted on the front panel3, and the manipulation knob71movably connected to the shuttle body20for shuttle rotation. It is preferred that the switch assembly17further includes a spring member81for returning the manipulation knob71to an original position.

The tact switches21,22,23,24,25, and26disposed on the PCB11individually perform separate functions. For example, if the first and the second tact switches21and22are designed to perform the fast-forwarding and rewinding functions, the third switch23may be located between the first and the second tact switches21and22to perform another predetermined function. Also, the fourth and fifth tact switches24and25are located outside of the second tact switch22to perform functions such as pausing and stopping.

FIG. 7is a view showing the switch assembly17ofFIG. 4in an assembled state,FIG. 8is a rear elevation view ofFIG. 7, andFIG. 9is a plan cross sectional view ofFIG. 8, which shows the main parts of an exemplary embodiment of the present invention more specifically. Referring toFIGS. 7 and 8, the shuttle body20includes a frame20′ fixed to the front panel3(not shown), and a first and a second tension ribs31and32operating with the first and the second tact switches21and22(not shown), and a knob holding shaft51connected to the manipulation knob71.

The first and the second tension ribs31and32extend from a lower portion of the frame20′ toward the first and the second tact switches21and22(not shown) in parallel to each other. The first and the second tension ribs31and32are elastically deformable in a vertical direction with respect to the frame20′. As the first and the second tension ribs31and32are elastically deformed to a lower portion, they turn on/off the corresponding first and the second tact switches21and22(not shown).

InFIG. 8, the first and the second tension ribs31and32respectively include protrusions41and42upwardly protruding from the connected portions to the frame20′, and inclined portions47and48formed at the ends of the protrusions41and42. The inclined portions47and48are shaped in arc pattern with respect to the knob holding shaft51, and maintained at a predetermined angle with respect to the corresponding protrusions41and42. The inclined portion47and48are pressed and released by an operating portion72of the manipulation knob71, which will be described in greater detail below, thereby being elastically deformed in a forward or a backward direction. Accordingly, the first and the second tension ribs31and32are elastically deformed in unison with the inclined portions47and48.

Meanwhile, between the first and the second tension ribs31and32is provided a third tension rib33extending toward the third tact switch23(not shown). Like the first and the second tension ribs31and32, the third tension rib33has a protrusion43upwardly protruding to operate with the manipulation knob71. The protrusion43is elastically deformed backward when being pressed at the front portion and in association with this, the third tension rib33is elastically deformed to turn on/off the third tact switch23.

Fourth and fifth tension ribs34and35operating with the fourth and the fifth tact switches24and25(not shown) may be located outside the second tension rib32. Like the first to the third tension ribs31,32, and33, the fourth and the fifth tension ribs34and35have protrusions44and45upwardly protruding. The manipulation knobs84and85(shown inFIG. 7) are connected to the protrusions44and45of the fourth and the fifth tension ribs34and35to be exposed to the outside through the knob holes8and9formed in the front panel3. When the manipulation knobs84and85are pressed backward, the fourth and the fifth tension ribs34and35are elastically deformed in unison with the protrusions44and45, thereby turning on/off the corresponding tact switches24and25(not shown).

Meanwhile, the knob holding shaft51is located in the center above the first and the second tension ribs31and32. The knob holding shaft51extends from a plate surface of the shuttle body20in a forward direction, and has a shaft hole51aformed in a center thereof. Also, guide recesses61and65, each forming a pattern of a partial arc, are located around the knob holding shaft51opposite to each other. The ends of each guide recess61and65prevent excessive normal/reverse rotations of the manipulation knob71.

Referring now toFIG. 9, a boss63protruding in an arc pattern is located between the knob holding shaft51and the guide recesses61and65(shown inFIG. 8). A spring recess for housing a spring member81is formed between the boss63and the knob holding shaft51. The spring member81may be a torsion spring. The boss63has a predetermined cutting part formed on a lower portion of the boss63to hold opposite ends82and83of the spring member81downward. The opposite ends of the spring member81held by the cutting part are elastically deformed only in a compressed direction.

Preferably, the shuttle body20with the above construction is integrally formed by injection molding. Referring back toFIG. 8, the first and the second tension ribs31and32may take various forms that are capable of directly operating with the operating portions72and73of the manipulation knob71without the protrusion41and42and the inclined portions47and48. For example, in order to be operated by the operating portions72and73of the manipulation knob71, the first and the second tension ribs31and32each have an inclined surface formed along the length of their front surface.

Meanwhile,FIG. 10is a rear elevation view showing the manipulation knob71. As shown inFIG. 10, the manipulation knob71includes a rotary shaft75connected to the shaft hole51aof the knob holding shaft51, the operating portions72and73operating with the first and the second tension ribs31and32, and connecting portions76and77movably received in the guide recesses (holes)61and65. The rotary shaft75protrudes toward the shuttle body20(not shown) along a center axis of the manipulation knob71to be rotatably connected to the shaft hole51aof the knob holding shaft51(as shown inFIG. 5). The manipulation knob71is rotatably connected to the knob holding shaft51and is partially exposed to the outside of the front panel3. A knurling78is preferably formed around the circumference on the outer surface of the manipulation knob71for the user to grip.

The connection portions76and77are provided in pairs and extend from the rear end of the manipulation knob71toward the shuttle body20, and have hooks76′ and77′ protruding outward from the ends of the connection portions76and77, respectively. The connection portions76and77are received in the guide recesses or holes61and65of the shuttle body20to shuttle-rotate along the length of the guide recesses or holes61and65. The hooks76′ and77′ are formed at the end of connection portions76and77are hooked into the guide holes or recesses61and65to prevent the manipulation knob71from being turned further than the length of the guide recesses or holes61and65.

The operating portions72and73are provided in pairs and protrude outward from the outer surface of the manipulation knob71in a radial direction. Operating portion72is a predetermined distance from operating portion73; the predetermined distance corresponding to the angle between the opposite ends82and83of the spring member81. Also, the operating portions72and73have contact protrusions72′ and73′ formed at their ends to contact the inclined portions47and48of the first and the second tension ribs31and32. Referring toFIGS. 7 and 8, the first and the second tension ribs31and32shuttle-rotate in the normal/reverse directions, the contact protrusions72′ and73′ move in unison with the inclined portions47and48of the first and second tension ribs31and32. As the contact protrusions72′ and73′ move along the inclined portions47and48in the normal/reverse directions, they press or release the first and the second tension ribs31and32, thereby turning on/off the corresponding tact switches21and22.

Referring now toFIG. 9, the operating portions72and73have locking protrusions72″ and73″ protruding toward the spring member81. The locking protrusions72″ and73″ operate with the opposite ends of the spring member81received in the spring recess of the shuttle body20. That is, the opposite ends82and83of the spring member81elastically press the locking protrusions72″ and73″ toward the outside so that the manipulation knob71is maintained at a position to press and release the first and the second tension ribs31and32.

In order to assemble a switch assembly17having the above construction, first, the spring member81is received in the spring recess of the shuttle body20. Next, the rotary shaft75of the manipulation knob71is inserted into the shaft hole51aof the knob holding shaft51of the shuttle body20. At this time, it is important that the locking protrusions72″ and73″ of the operating portions72and73correspond to the opposite ends82and83of the spring member81at the outside. Accordingly, due to the elasticity of the spring member81, it is possible for the manipulation knob71to shuttle-rotate between a position where the manipulation knob71releases the first and the second tension ribs31and32and a position where the manipulation knob71presses the first and the second tension ribs31and32.

The shuttle body20, assembled with the manipulation knob71, is fixed to the rear surface of the front panel3. The frame20′ of the shuttle body20has a connection recess (reference numeral27ofFIG. 8) formed along its longitudinal direction into which the shuttle body20is fixed. A plurality of connection members (not shown) formed on the rear surface of the front panel3are connected to the connection recess so that the shuttle body20is fixed to the front panel3. It is preferred that a shuttle ring (reference numeral91ofFIG. 4) is located between the front panel3and the shuttle body20. The shuttle ring91aids in smooth rotation of the manipulation knob71, which extends through the knob hole7in the normal/reverse directions to the exterior of the front panel3.

Meanwhile, the tact switches21,22,23,24,25, and26are fixed onto pre-set positions on the PCB11. The PCB11has tact switches21,22,23,24,25, and26installed on it and is connected to a predetermined position on the bottom of the case body. Accordingly, as the front panel3is assembled with the case body, the first and the second tension ribs31and32of the shuttle body20correspond to the first and the second tact switches21and22located on the PCB11.

A user can grip the manipulation knob71positioned at a press-release position and shuttle-rotate it in the normal/reverse directions. During the shuttle rotation of the manipulation knob71, the operating portions72and73elastically deform the first and the second tension ribs31and32. Then, the first and the second tact switches21and22are turned on/off to perform the corresponding functions. Thus, when the user ceases applying force to the manipulation knob71, the spring member81returns to the press-release position by the recovering force thereof.

When a user presses the manipulation knob71backward, the third tension rib33is elastically deformed to turn on/off the third tact switch23. It is preferable not to elastically deform the third tension rib33freely by the manipulation knob71. In this embodiment, an elastic supporting rib (a reference numeral29ofFIG. 7) is formed at a position corresponding to the third tension rib33with respect to the knob holding shaft51. The elastic supporting rib29presses the manipulation knob71forward, thereby preventing the third tension rib33from operating freely.

According to embodiments of the present invention as described above, assembling and disassembling of the switch assembly17becomes easy and simple because the shuttle body20is integrally formed with the knob holding shaft51by the injection molding and the tact switches are located on the PCB. Accordingly, manufacturing costs and maintenance costs can be reduced.

Also, the switch assembly17with a simple compact construction reduces the overall size of a product and allows the user to manipulate it with ease and convenience.

The foregoing embodiment and advantages are merely exemplary and are not to be construed as limiting the present invention. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art.