Keypad assembly and electronic device using the same

[0001] This application is related to two co-pending U.S. patent application Ser. Nos. 13/004,902, 12/953,758, all entitled “KEYPAD ASSEMBLY AND ELECTRONIC DEVICE USING THE SAME”, and the inventor is Bin Dai. The above-identified applications have the same assignee as the instant application and are concurrently filed herewith. The disclosures of the above-identified applications are incorporated herein by reference.

[0002] 1. Technical Field

[0003] The present disclosure relates to data input, and particularly, to a keypad assembly used in an electronic device.

[0004] 2. Description of the Related Art

[0005] Electronic devices often provide a keypad on a panel thereof, thus allowing control input for a power source or other component by the user.

[0006] A commonly-used keypad assembly is located on a housing of an electronic device. The housing defines a mounting port in a rear surface of the housing. The keypad assembly includes a keycap, a key switch, and an arched spring. The keycap is received in the mounting port, and a protrusion is arranged at a bottom of the keycap. The key switch includes a contact portion. The arched spring is sleeved on the protrusion and resists the housing. The protrusion resists a top of the spring. When the keycap is depressed, the spring is thereby elastically deformed, such that the protrusion presses the contact portion. When the keycap is released, the spring returns to its relaxed state and resists the protrusion. However, the keypad assembly has a larger volume because of the protrusion and the spring.

[0007] Therefore, there is room for improvement within the art.

[0014] Referring to FIGS. 1 and 2, an embodiment of an electronic device 100 includes a housing 101 and a keypad assembly 103 located on the housing 101. In the illustrated embodiment, the keypad assembly 103 is a main menu button and the housing 101 is a planar glass plate.

[0015] The keypad assembly 103 includes a keycap 20, a fixing bracket 30, a first fixing member 40, and a second fixing member 50. The first fixing member 40 fixes the keycap 20 to the fixing bracket 30. The second fixing member 50 fixes the fixing bracket 30 to the housing 101.

[0016] The keycap 20 includes a top cover 21, a filling portion 23, and a bottom cover 25. The top cover 21 includes an interface 212, a biasing surface 213, and a receiving frame 215. The biasing surface 213 is defined on a surface of the top cover 21 opposite to the interface 212. The receiving frame 215 is substantially rectangular, and located on a middle portion of the interface 212. In the illustrated embodiment, the biasing surface 213 is a concave depression defined in a side surface of the top cover 21. The filling portion 23 is received in the receiving frame 215. The bottom cover 25 is substantially circular, and fixed on the interface 212. The bottom cover 25 defines a through hole 251, corresponding to the receiving frame 215, in a center of the bottom cover 25. The top cover 21, the filling portion 23 and the bottom cover 25 are respectively made of different materials to optimize presentation and wear. In this embodiment, the filling portion 23 and the bottom cover 25 are made of black plastic. The top cover 21 is made of a transparent plastic resistant to wear, and integrally formed with the filling portion 23 and the bottom cover 25 by bi-color injection molding.

[0017] Referring to FIGS. 2 through 4, the fixing bracket 30 includes two support portions 31, a fixing portion 32, two connecting portions 34, and four resilient portions 35. Opposite ends of each connecting portion 34 are connected to the two support portions 31 via the resilient portions 35, such that the two support portions 31, two connecting portions 34 and the four resilient portions 35 cooperatively form a substantially rectangular frame. The four resilient portions 35 are all substantially Z-shaped, such that the connecting portions 34 are projected out from the support portions 31. The fixing portion 32 is located on a middle portion of the substantially rectangular frame, and opposite sides of the fixing portion 32 are connected to a middle portion of the connecting portions 34. The fixing portion 32 defines a through hole 321 in the center of the fixing portion 32.

[0018] In the illustrated embodiment, the first fixing member 40 and the second fixing member 50 are double-sided adhesive tape. Shape of the fixing member 40 is the same as that of the fixing portion 32 of the support bracket 30. Shape of the second fixing member 50 is the same as that of the support portion 31 of the fixing bracket 30.

[0019] The housing 101 defines a mounting port 102 in a middle portion of the housing 101. The top cover 21 of the keycap 20 is slidably received in the mounting port 102.

[0020] Referring to FIGS. 1, 2 and 5, during assembly of the keypad assembly 103, the first fixing member 40 is fixed to the fixing portion 32 of the fixing bracket 30. Then, the fixing portion 32 of the fixing bracket 30 is fixed to the bottom cover 25 of the keycap 20. The filling portion 23 is received in the through hole 321 of the fixing bracket 30. The second fixing member 50 is fixed the support portion 31, and the support portion 31 is fixed to the housing 101. The top cover 21 is received in the mounting port 102.

[0021] When the top cover 21 of the keycap 20 is depressed, the top cover 21 slides toward the mounting port 102 of the housing 101, such that the resilient portions 35 are elastically deformed. When the top cover 21 of the keycap 20 is released and return the keycap 20 to its original position, the resilient portions 35 return to a relaxed state and resist the keycap 20. Thereby, the resilient portions 35 can provide an elastic restoring force to the keycap 20, and without requiring additional dedicated resilient member and protrusion to be located on the keycap 20, and the occupied volume of the keypad assembly 100 is thereby decreased.

[0022] It is to be understood that the first fixing member 40 and the second fixing member 50 can also be glue, bolts, or a plurality of latching structures. The connecting portions 34 can also be omitted, whereby only two resilient portions 35 are present, directly interconnecting the support portions 31 and the fixing portion 32.

[0023] Finally, while the present disclosure has been described with reference to particular embodiments, the description is illustrative of the disclosure and is not to be construed as limiting the disclosure. Therefore, various modifications can be made to the embodiments by those of ordinary skill in the art without departing from the true spirit and scope of the disclosure as defined by the appended claims.