MOBILE TERMINAL WITH A SOLAR CELL

Abstract: A mobile terminal with a solar cell is disclosed. The mobile terminal has a main body, a battery and a flip cover. A receiver portion, a data display and a keypad are formed on the upper surface of the main body. The improvement comprises a solar cell attached to the outer surface of the flip cover to be exposed to the outside. According to the present invention, there is provided the mobile terminal having a solar cell, which is capable of providing sufficient electric power to the mobile terminal while the mobile terminal is positioned in a normal state where the upper surface of the mobile terminal is directed upward.

Description: MOBILE TERMINAL WITH A SOIAR CELL TECHNICAL FIELD The present invention relates, in general, to a mobile terminal with a solar cell and, more particularly, to a mobile terminal to the flip cover of which a solar cell is attached. BACKGROUND ART As well known to those skilled in the art, since a mobile terminal is generally carried in a user' s pocket or around a use' s neck, it is desirable that a mobile terminal is light in weight and small in size- In the meantime, the technology of obtaining a lightweight and small-sized battery for the mobile terminal has been pursued through the development of a nickel-cadmium (Ni-Cd) battery, a nickel-hydrogen (Ni-H) battery, a lithium- ion (Li-ion) battery, etc. However, since the battery technology lags behind the technology of developing a semiconductor that is mounted in the main body of the mobile terminal, there occurs a problem in which the battery of the mobile terminal is heavier and larger than the main body of the mobile terminal. In order to improve the performance of the battery, the inventor of the present invention proposed the invention of Unexamined Korean Pat. Publication No. 98-87892 entitled Storage Battery with a Solar Cell for a Mobile terminal". The patent discloses a battery that allows the battery to be charged by various light, thereby reducing inconvenience of charging the battery. However, since the battery of the patent is formed by attaching one or two solar cells to one or two surfaces of the battery, the battery must be detached from the mobile terminal or the mobile terminal must be turned upside down to be charged by light, thereby increasing the inconvenience of charging the battery using light. Additionally, Korean Pat. Publication No. 94-3280 entitled "Mobile terminal with a Solar Cell and Power Supply thereof" discloses a mobile terminal in which a solar cell is provided on the upper surface of the mobile terminal together with an data display that is always exposed to the outside, thereby allowing the battery to be charged by light in a normal state. However, since the solar cell is disposed together with a receiver portion in the vicinity of the data display on the upper surface of the mobile terminal, there occurs a shortcoming in which the size of the solar cell is limited. As a result, the solar cell is not practicable to the mobile terminal that consumes a great deal of electric power because the mobile terminal must produce the high frequency output of 600mW. DISCLOSURE OF THE INVENTION Accordingly, the present invention has been made keeping Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a mobile terminal having a solar cell, which is capable of providing sufficient electric power to the mobile terminal while the mobile terminal is positioned in a normal state where the upper surface of the mobile terminal is directed upward. In order to accomplish the above object, the present invention provides a mobile terminal having a main body, a battery and a flip cover, a receiver portion, a data display and a keypad being formed on the upper surface of the main body, wherein the improvement comprises a solar cell attached to the outer surface of the flip cover to be exposed to the outside. BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Fig. 1 is a perspective view showing the appearance of a mobile terminal with a solar cell in accordance with an embodiment of the present invention; Fig. 2 is a partially sectioned side view showing a mobile terminal in accordance with another embodiment of the present invention; Fig. 3 is a circuit diagram of another embodiment in which electricity is supplied for standby for the receipt of message; Fig. 4 is a circuit diagram of another embodiment in which electricity generated by a solar cell is supplied to a main body and a battery at the same time; Fig. 5 is a side view showing contacts connecting the solar cell of a flip cover and a main body to each other; Fig. 6 is a perspective view showing a flexible cable connecting the solar cell of a flip cover and a main body to each other; and Fig. 7 is a perspective view showing a mobile terminal of another embodiment in which its battery is disposed and sealed in its main body. BEST MODE FOR CARRYING OUT THE INVENTION Reference now should be made to the drawings, in which the same reference numerals are used throughout the different drawings to designate the same or similar components. As depicted in Fig. 1, a mobile terminal in accordance with the present invention generally comprises a main body "a", a battery 3 and a flip cover 5. A receiver portion 1, a data display 2 and a keypad are formed on the upper surface of the main body "a". In accordance with a feature of the present invention, a solar cell 6 is attached to the outer surface of the flip cover 5 to be exposed to the outside. When the mobile terminal of the present invention is deposited on a desk or the top of the dashboard of an automobile in a normal state where the data display 2 is directed upward, light reaches the solar cell 6 and the solar cell 6 generates electricity using the light. According to the present invention, since the solar cell 6 can be disposed all over the entire outer surface of the flip cover 5, the solar cell 6 can generate sufficient electricity necessary for charging the battery 3 of the mobile terminal. The electricity generated by the solar cell 6 may be supplied from the solar cell 6 of the flip cover 5 to the main body "a" through contacts 7 and 7' or a flexible cable 8. The electricity supplied to the main body "a" is supplied to the battery 3 detachable to the main body ""a", and the battery 3 is charged with the electricity. The solar cell 6 may be fabricated of one of various materials such as silicon (Si) , gallium arsenide (GaAs) , cadmium sulphide (CdS), indium phosphide (InP) and combinations thereof. However, the solar cell 6 is preferably formed of silicon from an economical point of view. Of course, since an open-end photo voltage is about 0.55V per each element of the silicon solar cell, the solar cell 6 must be used in conjunction with a booster circuit 11 for increasing the open-end photo voltage of about 0.55N to the electric source voltage of the mobile terminal of a range of 3 . 8N to 6N. If the mobile terminal of the present invention is utilized together with the above-described "Storage Battery with a Solar Cell for a Mobile terminal" disclosed by Unexamined Korean Pat. Publication No. 98-87892, there can be obtained the improved convenience of charging battery. That is, if a battery with a solar cell 6' at its rear surface is mounted to the main body of the mobile terminal of the previous embodiment, the charging of the battery can always be performed through any surface of the mobile terminal exposed to the outside. Such an example is described in Fig. 2. In the meantime, since the solar cell 6 can obtain the light of strong energy when the solar cell 6 is exposed to a direct ray of light, the solar cell 6 can perform the sufficient generation of electric power in this case. If it is determined by a comparator 9 that a voltage generated by the solar cell 6 is greater than a predetermined voltage, the solar cell 6 is rendered not to supply electricity to the battery 3 by a semiconductor relay 10 and simultaneously the solar cell 6 is rendered to supply to the main body "a" sufficient electricity necessary for standby for the receipt of message, as shown in Fig. 3. In addition, if a voltage generated * by the solar cell 6 is greater than the output voltage of the battery 3, the solar cell 6 is rendered to supply electricity to both the battery 3 and the main body "a" through one or more diodes 12, as shown in Fig. 4. In the present invention, a fixed contact 7 and a movable contact 7' may be disposed so as to transmit electricity from the solar cell 6 of the flip cover 5 to the main body a". In more detail, as illustrated in Fig. 5, the movable contact 7' is disposed on the lower inner end of the flip cover 5 and the fixed contact 7 is disposed on the lower inner end of the keypad 4 of the main body "a", so that electricity generated by the solar cell 6 can be supplied to the main body "a" for standby for the receipt of message or for the charging of the battery 3. Furthermore, for the transmission of electricity from the solar cell 6 of the flip cover 5 to the main body "a", a flexible cable 8 may be utilized. That is, as shown in Fig. 6, the lower inner end of the main body "a" and the solar cell 6 of the flip cover 5 are connected to each other by the flexible cable 8. In accordance with a further embodiment of the present invention, a lithium-ion battery 3' is disposed and sealed in the main body "a", the lithium-ion battery 3' is continuously charged with electricity by the solar cell 6 during standby for the receipt of message and the main body "a" is supplied with electricity by the lithium-ion battery 3' during a call, thereby utilizing the lithium-ion battery 3' in a fixed state. Meanwhile, according to the present invention, since the battery is charged by the solar cell 6 from time to time, a lithium-ion battery without a memory effect or the other conventional batteries having such characteristics may be preferably utilized for the mobile terminal of the present invention. Although the examples in which the present invention is applied to mobile terminals are depicted in the drawings, the present invention, of course, can be applied to various movable communication terminals, such as a cordless phone, a Portable Digital Assistant (PDA) that performs communication through a data link kit, a palmtop computer and the like. INDUSTRIAL APPLICABILITY' As described above, the present invention provides a mobile terminal with a solar cell, which is capable of obtaining electricity simply by depositing the mobile terminal on a desk or table or hanging the mobile terminal around a user' s neck, thereby supplying electricity for standby for the receipt of message and the charging of its battery. As a result, the consumption of the battery can be minimized, so that the usable period of the battery is considerably increased. Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims: CLAIMS : 1. In a mobile terminal having ' a main body, a battery and a flip cover, a receiver portion, a data display and a keypad being formed on an upper surface of the main body, the improvement comprising a solar cell attached to an outer surface of the flip cover to be exposed to the outside. 2. The mobile phone according to claim 1, further comprising another solar cell attached to a rear surface of said battery. 3. The mobile terminal according to claim 1, wherein said main body is directly supplied with electricity for standby for receipt of message by said solar cell. 4. The mobile terminal according to claim 1, wherein said battery is supplied with electricity for charging by said solar cell. 5. The mobile terminal according to claim 1, wherein said solar cell of the flip cover and said main body are electrically connected to each other by a movable contact and a fixed contact, said movable contact being formed on an lower inner end of the flip cover, said fixed contact being formed on an lower inner end of the keypad of the main body. 6. The mobile terminal according to claim 1, wherein said solar cell of the flip cover and said main body are electrically connected to each other by a flexible cable. 7. The mobile terminal according to claim 1, wherein said battery is disposed and sealed in said main body and an output of said solar cell is directly connected to said battery. AMENDED CLAIMS [received by the International Bureau on 3 July 2001 (03.07.01); original claim 1 amended; original claim 2 cancelled; remaing claims unchanged (1 page)] 1. In a mobile terminal having a main body, a battery and a flip cover, a receiver portion, a data display and a keypad being formed on an upper surface of the main body, the improvement comprising a solar cells attached to an outer surface of the flip cover and said battery to be exposed to the outside respectively. 3. The mobile terminal according to claim 1, wherein said main body is directly supplied with electricity for standby for receipt of message by said solar cell. 4. The mobile terminal according to claim 1, wherein said battery is supplied with electricity for charging by said solar cell. 5. The mobile terminal according to claim 1, wherein said solar cell of the flip cover and said main body are electrically connected to each other by a movable contact and a fixed contact, said movable contact being formed on an lower inner end of the flip cover, said fixed contact being formed on an lower inner end of the keypad of the main body. 6. The mobile terminal according to claim 1, wherein said solar cell of the flip cover and said main body are electrically connected to each other by a flexible cable. 7. The mobile terminal according to claim 1, wherein said battery is disposed and sealed in said main body and an output of said solar cell is directly connected to said battery. Statement under Article 19(1) According to the International Search Report we would like to request amendment of claims in this present patent application as attached sheet of corrected claims. Please refer to the explanation of correction as below. 1. In claim 1, "an outer surface of the flip cover to be exposed to the outside" in line 6 & 7 page 9 of Specification is replaced by "an outer surface of the flip cover and said battery to be exposed to the outside respectively". 2. Claim 2 is cancelled for incorporation into claim 1.

Inventors: LEEM SUNG-MUK, LEEM, SUNG-MUK
Applicants: LEEM SUNG MUK, LEEM, SUNG-MUK
Application year: 2000
Main classification: H04B1
IPC codes: H04B1, H04M1