A cigarette lighter

Abstract: A cigarette lighter is disclosed. It operates by acting on a push button (4) which opens a valve (20) to release gas (13) from a tank (14) and activate a sparking means (6, 7) for igniting the released gas (13). The lighter has a "self-retrieving" safety mechanism (2) which is simple and easy for an adult to operate and which can reliably prevent unintentional operation of the lighter, such as by a child. The safety mechanism (2) has an elongated resilient bar (2) provided at one end with an operating member (1). The safety mechanism (2) has a normal position in which it prevents operation of the push button (4) and an operating position, to which the safety mechanism (2) can be moved by the operating member (1) in a one step motion, in which the push button (4) can be operated. Upon operation, the safety device (2) automatically returns to its normal position.

Description: The present invention relates to a cigarette lighter, and in particular to a cigarette lighter with a safety-mechanism whereby accidental operation of the lighter, particularly by a young child, is prevented. BACKGROUND TO THE INVENTION Re-fillable lighters are known and their operation involves a straightforward push button action to open a valve, release gas from a tank and to ignite the gas by means of a spark. Also known from US Patent No. 5538417 is an ultra-thin cigarette lighter with a self retrieving safety mechanism which is simple and easy for an adult to operate and which can reliably prevent unintentional use of the lighter. Such a cigarette lighter operates by acting on a push button which opens a valve to release gas from a tank and activates a sparking means for igniting the released gas. The lighter has a "self-retrieving" safety mechanism which is simple and easy for an adult to operate and which can reliably prevent unintentional operation of the lighter, such as by a child. The safety mechanism is in the form of an elongated resilient bar provided at one end with an operating member located in a first short portion of a slot in the push button. Said safety mechanism having a normal position in which the safety device prevents operation of the push button by engaging an end portion of said first slot portion, and an operating position, to which the safety device can be moved by means of the operating member into a second slot portion in said push button of a longer length than said first slot portion and in which the push button can be operated, the safety device automatically returning to its normal position after use of the cigarette lighter. The operation of the cigarette lighter of US Patent No. 5538417 is a two-step process. BRIEF SUMMARY OF THE INVENTION It is an object of the present invention to provide a cigarette lighter with a self-retrieving safety mechanism which can be operated by a one-step process and is thus simpler and easier for an adult user to operate than known devices, but which can reliably prevent unintentional use of the lighter, e.g. by a child. It is also an object of the present invention that the said safety mechanism can be used in both conventional and ultra thin cigarette lighters. In accordance with the present invention, there is provided a cigarette lighter including a tank for a combustible gas under pressure; a valve which is normally closed to prevent gas from exiting the tank, but which can be opened to allow gas to escape from the tank through a nozzle; a valve actuator operable to open the valve; a spark means operable to produce a spark in the vicinity of the nozzle and cause ignition of gas escaping from the tank when the valve is opened by the valve actuator; a spark means holder having an upstanding extension with an end; a push button operable by engagement of a user's finger to operate the valve actuator, open the valve and operate said spark means, and a movable safety device in the form of an elongated resilient bar provided at one end with a rotatable operating member and at the other end with an extension, said safety device being movable between a normal position in which the safety device prevents operation of the push button by means of the extension engaging the end of the upstanding extension of the spark means holder, and an operating position to which the safety device can be moved by rotation of the operating member, whereby the extension of the safety device is moved out of engagement with the end of the upstanding extension of the spark means holder simultaneously as the push button is pushed inwards so that the extension moves down the side of the upstanding extension, returning to its normal position after use of the cigarette lighter, characterized in that the safety device is movable by rotation of said operating member about an axis which is substantially parallel to the direction of movement of said push button relative to the spark means holder. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described, by way of example, with reference to the accompanying drawings in which: FIG. 1 is a front view of a cigarette lighter in accordance with the present invention, FIG. 2 is a vertical part section through the cigarette lighter of FIG. 1 with the safety device and lighter in normal, non-operating position, FIG. 3 is an exploded perspective view of part of cigarette lighter in the normal, non-operating position of FIG. 1, FIG. 4 is a perspective view of the safety device in operating position, and FIG. 5 is a vertical section through an alternative conventional form of cigarette lighter with the safety device and lighter in the normal, non-operating position. DESCRIPTION OF THE EXAMPLE As shown in Figure 1, the cigarette lighter of the present invention comprises a gas tank 14, a body 15 united to the tank 14, e.g. by ultra-sonic welding, and a windshield 8 mounted on the body 15. The cigarette lighter is provided with a flame control means 12 and an operating push button 4, which has mounted on it an operating member 1 having a boss 1a. In FIG. 2, the cigarette lighter is shown with the operating member 1 in its normal, non-operating position. A locking member 2 provided with an extension 2a is connected to the operating member 1 and is arranged within a recess 4a of a push button 4. A return spring 3 biases the operating member 1 towards its non-operating position. Also illustrated in Figure 2 is a piezo unit 6. One of its ends is mounted in the push button 4 and it also has an electrode 7 which is mounted in a piezo holder 5 having an upstanding extension 5a. The extension 2a of the locking member 2 engages the upstanding extension 5a of the piezo holder 5 and so obstructs the movement of push button 4 towards the piezo holder 5. Mounted in the push button 4 is one end of a reciprocating valve actuator 10. The other end of the valve actuator 10 co-operates, when push button 4 is pushed in, with a valve 20. The valve 20 has a substantially U-shaped metal plate 11 which co-operates with the valve actuator 10 to urge the stem of the valve 20 upward, opening the valve 20 and discharging gas through nozzle 21 which is surrounded by an ignition spring 9. When closed, the valve 20 prevents the gas 13 from exiting the tank 14. The configuration of the locking member 2, the operating member 1 and the piezo holder 5 are shown in greater detail in Figure 3, an exploded view. The locking member 2 is made of resilient or elastic material such as plastic and is provided with a return spring 3 arranged to be mounted on an extension 2b of the locking member 2. The end of extension 2b is arranged to engage the operating member 1. The locking member 2 is provided with a second extension 2a which, in the non-operating position, engages the end of the upstanding extension 5a of the piezo holder 5. Figure 4 shows the operation of the lighter. As the boss 1a of the operating member 1 is rotated, the locking member 2 is rotated about its longitudinal axis A-A (see Fig. 3), whereby the extension 2a of the locking member 2 is moved out of engagement with the end of the upstanding extension 5a of the piezo holder 5 and as the push button 4 is simultaneously pushed into the windshield 8 (not shown), the extension 2a moves down the side of upstanding extension 5a. This causes the valve actuator 10 to engage the under side of the U-shaped metal plate 11 of valve 20 urging the stem of the valve 20 upwardly to release gas from the tank 14. The piezo unit 6 is simultaneously compressed and emits sparks from the electrode 7. This ignites gas around the ignition spring 9 of nozzle 21 and generates a flame. It can also be seen in Figs. 3 and 4 that the push button 4 is movable relative to the piezo holder 5 in the directions indicated by the arrows B-B, which is also parallel to the longitudinal axis A-A of the locking member 2. As shown in Figure 5 the safety device can be used in a conventional cigarette lighter. Since the components of a conventional cigarette lighter are essentially the same as that of the ultra-thin cigarette lighter described above, it will not be described in detail other than to comment that the U-shaped metal plate 11 is replaced by a lever 11a.

Claims: A cigarette lighter including: a tank (14) for a combustible gas (13) under pressure; a valve (20) which is normally closed to prevent gas (13) from exiting the tank (14), but which can be opened to allow gas (13) to escape from the tank (14) through a nozzle (21); a valve actuator (10) operable to open the valve (20); a spark means (6, 7) operable to produce a spark in the vicinity of the nozzle (21) and cause ignition of gas (13) escaping from the tank (14) when the valve (20) is opened by the valve actuator (10); a spark means holder (5) having an upstanding extension (5a) with an end; a push button (4) operable by engagement of a user's finger to operate the valve actuator (10), open the valve (20) and operate said spark means (6, 7), and a movable safety device (2) in the form of an elongated resilient bar provided at one end with a rotatable operating member (1) and at the other end with an extension (2a), said safety device (2) being movable between a normal position in which the safety device (2) prevents operation of the push button (4) by means of the extension (2a) engaging the end of the upstanding extension (5a) of the spark means holder (5), and an operating position to which the safety device (2) can be moved by rotation of the operating member (1), whereby the extension (2a) of the safety device (2) is moved out of engagement with the end of the upstanding extension (5a) of the spark means holder (5) simultaneously as the push button (4) is pushed inwards so that the extension (2a) moves down the side of the upstanding extension (5a), returning to its normal position after use of the cigarette lighter, characterized in that the safety device (2) is movable by rotation of said operating member (1) about an axis which is substantially parallel to the direction of movement of said push button (4) relative to the spark means holder (5). A cigarette lighter according to Claim 1, further characterized in that the safety device (2) is movable by rotation of said operating member (1) about an axis which is substantially parallel to the length of the safety device (2). A cigarette lighter according to Claim 1 further characterized in that the valve (20) includes a substantially U-shaped metal plate (11) having upturned ends to engage with the valve actuator (10). A cigarette lighter according to Claim 3 further characterized in that the valve actuator (10) comprises an elongated metal bar, one end of which is fixed into the push button (4) and the other end of which is shaped to engage the under sides of the up-turned ends of the metal plate (11). A cigarette lighter according to 1 further characterized in that the spark means (6, 7) is a piezo means, one end of which is located in the push button (4). A cigarette lighter according to Claim 5 further characterized in that the piezo holder (5) is provided with an electrode (7) and a piezo body (6) movably located in said holder (5). A cigarette lighter according to Claim 1 further characterized in that a return spring (3) biases the operating member (1) towards its normal position.

Inventors: CHAN LEUNG, CHAN, LEUNG
Applicants: SHENZHEN BAILINGDA LIGHTERS &, SHENZHEN BAILINGDA LIGHTERS & ELECTRICAL PRODUCTS CO. LTD.
Application year: 1999
Main classification: F23Q2
IPC codes: F23Q2