Patent Application
20060278502
1. Field of the Invention
The present invention relates to a key input apparatus of an electronic device. More particularly, the present invention relates to a key input apparatus of an electronic device having a rubber-contact member included in the key input apparatus.
2. Description of the Related Art
In general, key input apparatuses are used to input a control signal desired by a user. Such key apparatuses are included in the main bodies of electronic devices, such as printers, copy machines, and facsimiles, or control devices of electronic devices, such as remote controls of TVs and VCRs. There exist various kinds of key input apparatuses, most of which include carbon contacts on a printed circuit board (PCB). Such configuration allows a user to input a signal by pushing a key to thereby contacts a contact portion below the lower surface of the key to a carbon contact. An elastic substance such as rubber or silicon, which can easily deform and restore to its initial shape, is used to relocate a pushed key to an original location. A rubber-contact member has a structure including a plurality of keys placed on a plate made of an elastic substance such as rubber or silicon.
The plurality of keys of the rubber-contact member are at locations corresponding to carbon contacts. In other words, circuit contacts, of a PCB, respectively protrude towards the upper portion of the circuit contacts in a dome or conical shape, and have key contacts, which are also carbon contacts, below the lower surfaces of the keys. Each skirt part forming an incline of the dome or conical shape has a thinner thickness compared to other parts that contact the PCB in order to be efficient for repeated deformations and restorations.
Most electronic devices include key input apparatuses having keys which are classified into groups according to their functions. For example, a numeric key group for inputting numbers, a memory key group for shortcut dial, and a function key group for scanning, printing, and the like are usually arranged on the surface of a facsimile. In this case, to reduce the manufacturing cost of devices, in other words the parts' manufacturing cost and assembly cost, it is preferable that the rubber-contact member be formed in one body over a wide area in which various key groups are arranged. However, an increase of the size of the rubber-contact member may cause problems as described below.
The key structure of the rubber-contact member 20 having the key contacts 25 protrudes to the upper direction of the circuit contacts 31 in a dome or conical shape, and the key contacts 25 are placed on the lower surface of the keys 21. Each skirt part 26 forming an incline of the dome or conical shape has a thinner thickness compared to other parts of the rubber-contact member 20 in order to be efficient for repeated deformations and restorations.
The rubber-contact member 20 for various key groups can be formed in one body over a wide area. However, in this case, the rubber-contact member 20 has a large manufacturing tolerance due to a material characteristic and expands due to heat generated by an electronic device.
The key contacts 25 of the rubber-contact member 20 must be arranged to match the corresponding circuit contacts 31. If the size of the rubber-contact member 20 is changed due to the manufacturing tolerance thereof or due to heat expansion, an arrangement and/or alignment error between each key contact 25 and the corresponding circuit contact 31 gradually increases with regard to the distance from the left end of
The arrangement error can cause an interference between each key 21 and the corresponding key hole 11 and a faulty operation since each key contact 25 and the corresponding circuit contacts 31 cannot be smoothly contacted.
Accordingly, there is a need for an improved contact member which reduces alignment and arrangement errors, and an apparatus comprising the same.
Exemplary embodiments of the present invention address at least the above problems and/or disadvantages and provide at least the advantages described below. Accordingly, an aspect of the present invention is to provide a rubber-contact member formed in one body for a plurality of key groups such that its size can be easily adjusted to reduce an arrangement and/or alignment error with respect to a printed circuit board (PCB).
The exemplary embodiments of the present invention also provide a key input apparatus for use in an electronic device, the apparatus including a rubber-contact member by which proper alignment and arrangement between key holes in a cover and circuit contacts of a PCB is achieved.
According to an exemplary aspect of the present invention, there is provided a rubber-contact member having a plurality of key contacts corresponding to a plurality of circuit contacts located on the upper surface of a printed circuit board (PCB), the rubber contact member comprising foldable parts for partitioning an entire area into two or more zones, making an interval between the zones to be easily adjusted while the foldable parts deform, and therefore allowing the zones to be in a one-to-one correspondence with relevant zones of the PCB.
The exemplary rubber-contact member may be formed long in a horizontal direction to correspond to the plurality of key groups, the foldable parts may be formed across the rubber-contact member in a vertical direction, and therefore, the zones may be arranged in the horizontal direction. This is because the manufacturing tolerance and thermal expansion have a higher effect in the longitudinal direction of the rubber-contact member. The horizontal direction and the vertical direction are relatively perpendicular to each other.
The exemplary foldable parts may be formed to have a thinner thickness compared to other parts, and may be formed in various shapes, for example, they may be formed to have at least one convex area.
Each of the zones partitioned by the exemplary foldable parts may comprise a location limitation part to make the rubber-contact member maintain contact with the relevant zones of the PCB. The exemplary location limitation parts may be formed in various shapes, for instance, a hole shape or a dome shape to be easily combined with ribs of the PCB or a cover.
According to another exemplary aspect of the present invention, there is provided a key input apparatus comprising a printed circuit board (PCB) having a plurality of circuit contacts on the upper surface thereof, a rubber-contact member having a plurality of key contacts corresponding to the plurality of circuit contacts and a cover on which a plurality of key holes are formed to expose keys located above the key contacts.
The keys may be formed in one body with the rubber-contact member. When a keypad may be placed on the key contacts, the keys may be buttons installed on the keypad.
Other objects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.
Throughout the drawings, the same drawing reference numerals will be understood to refer to the same elements, features, and structures.
Exemplary embodiments of the present invention will now be described more fully with reference to the accompanying drawings.
The rubber-contact member 50 is later disposed on a PCB so that the key contacts are arranged above circuit contacts (not shown) of the PCB. In the rubber-contact member 50, each of the two foldable parts 52 can be made narrower or wider such that locations of the zones 57, 58, and 59 can be adjusted to match relevant zones of the PCB.
The PCB 60 having a plurality of circuit contacts 61 is located below the cover 40 of the key input apparatus, and the rubber-contact member 50 having a plurality of key contacts 55 is located on the PCB 60. The plurality of key contacts 55 are in a one-to-one correspondence with the plurality of circuit contacts 61.
The key structure of the rubber-contact member 50 may be any structure which can be applied to conventional rubber-contact members. For example, the rubber-contact member 50 can protrude in the area of the circuit contacts 61 in a dome or conical shape, and the plurality of key contacts 55 can be located on the lower surfaces of the protrusions. In one exemplary embodiment, each skirt part 26 forming an incline of the dome or conical shape has a thinner thickness compared to other parts of the rubber-contact member 50 so as to be efficient for repeated deformations and restorations. Each key 51 can be formed above each key contact 55 in one body with the rubber-contact member 50 and exposed through each key hole 41 of the cover 40.
The rubber-contact member 50 comprises foldable parts 52 for partitioning the area into two or more zones. According to the first exemplary embodiment 200, the two foldable parts 52 divide the rubber-contact member 50 into three zones 57, 58, and 59. Each of the foldable parts 52 has a relatively thin thickness and comprises at least one convex area. The foldable parts 52 are relatively easily deformed, and therefore, the width of each foldable part 52 can be widened or narrowed to adjust locations of the zones 57, 58, and 59.
Thus, even if the rubber-contact member 50 formed in one body over a wide area has a large manufacturing tolerance, the zones 57, 58, and 59 in which the plurality of keys 51 are provided can be arranged to match the relevant zones of the PCB 60 by adjusting the locations of the zones 57, 58, and 59.
Due to the combination of the location limitation ribs 43, the holes formed in the location limitation parts 53, and the location limitation holes 63, the rubber-contact member 50, the PCB 60, and the cover 40 can be easily arranged, and even if the size of the rubber-contact member 50 changes, the alignment and arrangement state can be maintained since only the foldable parts 52 are slightly changed.
Locations of zones of the rubber-contact member 50 adjacent to the foldable part 52 can be adjusted in the arrow directions.
As described above, according to exemplary embodiments of the present invention, a rubber-contact member is partitioned into a plurality of zones by foldable parts, and intervals between the zones can be easily adjusted within a deformable range of the foldable parts. Thus, each zone of the rubber-contact member can be arranged to match each corresponding zone of a PCB, thereby reducing an arrangement and/or alignment error between them. That is, by using a single body type rubber-contact member corresponding to a plurality of key groups, the quality of a key input apparatus is increased by guaranteeing correctness of an arrangement between a PCB and a rubber-contact member.
In addition, in the key input apparatus according to exemplary embodiments of the present invention, key holes in a cover, keys of the rubber-contact member, and circuit contacts of the PCB have a good arrangement and alignment over a wide area, and the arrangement of the rubber-contact member can be maintained even after being assembled in the key input apparatus regardless of thermal expansion and other factors.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims and the full scope of equivalents thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-49201 | Jun 2005 | KR | national |
This application claims the benefit under 35 U.S.C. §119(a) of Korean Patent Application No. 10-2005-0049201, filed on Jun. 9, 2005, in the Korean Intellectual Property Office, the entire disclosure of which is hereby incorporated by reference.
