Abstract:
A safety device for gas burner includes a securing member, a press member, a slidable member, a retaining member and a button member. By manipulating the press member downwardly to reduce the height thereof, a connecting rod of the slidable member displaces as a result of loss of support from a lap piece, with an abutting rod contacting a stop ice. The connecting rod laps an upper portion of the lap piece so that the press member cannot rebound and is positioned. At this time, when the button member is pressed, an ignition means is simultaneously actuated, and the wall hook causes a gas supply means to supply fuel gas to a burner device. The fuel gas is ignited by means of the ignition means, and a wall rod abuts against a trigger rod. By pressing the retaining member, a fastening rod fastens the gas supply means in position to maintain supply of fuel gas. After use, the button member returns to its original position and is automatically retained by the press member.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a safety device for a gas burner, more particularly to a safety device adapted for use in different models of gas burners. The safety device can be automatically locked after use of the gas burner so as to ensure safety. 
     2. Description of Related Art 
     There are numerous instances of fire accidents caused by children playing with gas burners or stoves. Therefore, many countries have made relevant safety regulations stipulating installation of safety devices on gas burners, such as those disclosed in U.S. Pat. Nos. 5,460,521 and 5,741,128 to the inventor of this invention. According to these patents, when a gas burner is not in use, it is in a locked state. To use the gas burner, the safety device has to be released. The releasing operation is quite complicated, thereby making it relatively difficult for children to conduct. However, the safety device has to be locked manually after use, which is not very convenient. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to provide a safety device for a gas burner to eliminate the drawbacks with the prior art. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and other features and advantages of the present invention will be more clearly understood from the following detailed description and the accompanying drawings, in which, 
     FIG. 1 is an exploded perspective view of a safety device of the present invention and a gas burner; 
     FIG. 2 is a top sectional view of FIG. 1 in an assembled state and prior to operation; 
     FIG. 3 is a sectional view taken along line IV—IV of FIG. 2; 
     FIG. 4 is a sectional view taken along line V—V of FIG. 2; 
     FIG. 5 is a top sectional view of the present invention illustrating how the safety device is released; 
     FIG. 6 is a top sectional view of the present invention showing the safety device in a released state; 
     FIG. 7 is a sectional view taken along line VI—VI of FIG. 6; and 
     FIG. 8 is a sectional view taken along line VII—VII of FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to FIGS. 1 to  4 , the preferred embodiment of a safety device according to the present invention includes a securing member  1 , a press member  2 , a slidable member  3 , a retaining member  4 , and a button member  5 . 
     The securing member  1  is in the form of a seat fixedly provided on the top of a liquefied gas container (A). One side of the securing member  1  has a bearing means  11  projecting therefrom, which includes two support posts  111  with a guide groove  112  therebetween for insertion of the press member  2  and straddling of the button member  5 . The inner side of the guide groove  112  is formed with a guide chamber  113  communicated therewith for receiving and positioning the press member  2  when the latter displaces downward. Further, between the bearing means  11  and a wall edge  13  on the opposite side, there are disposed a connecting means  12  and a pivotal connecting means  14 . The connecting means  12  includes a first positioning pin  121  and a first positioning groove  122  for connection and positioning of the slidable member  3 . The pivotal connecting means includes a second positioning pin  141  and a second positioning groove  142  for connection and positioning of the retaining member  4 . In addition, in order that the securing member  1  can be connected to a supporting means (D), the bottom portion thereof corresponding to a support post (D 1 ) of the supporting means (D) is provided with a seat groove  15  (see FIG. 3) such that the securing member  1  can slidably displace along the support rod (D 1 ) and be positioned. In addition, the securing member  1  is provided with a connecting hole  16  in a suitable position for passage of a threaded rod  17  to secure fixedly the securing member  1  on the top of the gas container (A). 
     The press member  2  is in the form of a key that has one side provided with a press key  21  and a key neck  22 . The key neck  22  is inserted into the guide groove  112  and the press key  21  is exposed therefrom between two support posts  111 . In addition, the other side of the key neck  22  has a stop piece  23  extending integrally and longitudinally therefrom and having a width corresponding to that of the guide groove  113 . The bottom portion has a lap piece  24  extending laterally therefrom and being provided with a connecting hole  25  for receiving a retractable element  6 , such as spring. An upright post  26  is disposed between stop piece  23  and lap piece  24  as reinforcement. The two lateral sides thereof are respectively formed with a connecting groove  27 . When the press member  2  is not actuated, the stop piece  23  abuts against a bottom edge of the button member  5  to prevent it from pressing an ignition means (C). When the press member  2  is manipulated downwardly, the lap piece  24  is received in the guide chamber  113  to compress the retractable element  6  so that the overall height is reduced. Then, the button member  5 , unblocked by the stop piece, can proceed with pressing. 
     The slidable member  3  is a one-piece member having a sliding means  31  disposed on one side to corresponding to the connecting means  12 , with a retractable element  6 , such as a spring, disposed therebetween, so that the slidable member  3  can horizontally displace relative to the securing member  1 . The sliding means  31  includes an elongated fitting hole  311  engaging the first securing pin  121  so that the slidable member  3  can displace along the surface of the securing member  1 . A slide groove  312  in one side of the bottom side of the fitting hole  311  cooperates with the first positioning groove  122  to enclose a retractable element  6 . When the slidable member  3  is subjected to an external force, it will compress the retractable element  6  to generate displacement. In addition, the bottom portion on the other side of the slidable member  3  is provided with a connecting rod  32  and an abutting rod  33  extending from a front end thereof such that a clearance is defined therebetween. The abutting rod  33  is formed with a rod groove  34  corresponding to the upright post  26  to facilitate insertable connection of the two. When the press member  2  is not actuated, the lap piece  24  abuts against the connecting rod  32 , and there is a clearance between the abutting rod  33  and stop piece  23 . When the press member  2  is manipulated downwardly, due to reduction in height, the slidable member  3  will displace laterally as a result of extension of the retractable element  6 , thereby causing the abutting rod  33  to contact the stop piece  23 , and the connecting rod  32  to lap on the lap piece  24 . As such, the press member  2  cannot bounce back, i.e. resume its original position, thereby relieving the interference against the button member  5 . Further, the slidable member  3  has a trigger rod  35  extending laterally therefrom, which is linked up with the button member  5 . 
     The retaining member  4  is also a one-piece member. A middle portion thereof is provided with a sliding means  41  corresponding to the pivotal connecting means  14 , with a retractable element  6 , such as spring, disposed therebetween, so that the retaining member  4  can horizontally displace relative to the securing member  1 . The sliding means  41  includes an elongated fitting hole  411  for receiving the second positioning pin  141  so that the retaining member  4  can displace along the surface of the securing member  1 . A sliding groove  412  in one side of a bottom side of the fitting hole  411  cooperates with the second positioning groove  142  to enclose a retractable element  6 . When the retaining member  4  is subjected to an external force, it will compress the retractable element  6  to generate displacement. In addition, the retaining member  4  has a fastening rod  42  projecting from an inner side thereof, and a press rod  43  provided on an outer side thereof. When a sliding plate (B 1 ) of a gas release means (B) is pushed by the button member  5 , gas is supplied. At this time, by pressing a press rod  43  to bring the fastening rod  42  into engagement with the sliding plate (B 1 ), the sliding plate (B 1 ) can be prevented from resuming its original position, thereby ensuring continuous supply of fuel gas to the supporting means (D). 
     The button member  5  is a push button straddling the bearing means  11 . The front and rear side walls  51 ,  52  thereof straddle the surface of the securing member  1 , and are respectively provided with a wall hook  511  and a wall rod  521  for connecting the sliding plate (B 1 ) of the gas release means (B) and forming a contact relationship with the trigger rod  35 . In addition, the top portion of the button member  5  is provided with a guide piece  53  straddling a support plane of the supporting means (D) so as to serve as a basis for displacement. Moreover, a biasing element  7 , such as a spring, is disposed between the supporting means (D) and the side wall  51  to enhance the resilience of the button member  5 . In the present invention, after assembly of the safety device and the burner, only the button member  5 , push button  21  and press rod  43  will be exposed on the outside of a top cover F. 
     With further reference to FIGS. 2 to  8 , prior to operation, the abutting rod  33  of the slidable member  3  is received in the connecting groove  27 , with the connecting rod  32  abutting against the lap piece  24 , and the stop piece  23  abutting against the bottom edge of the button member  5  so the latter cannot be pressed. At this time, the wall hook  511  of the press member  5  maintains a secure connecting relationship with the sliding plate (B 1 ), as shown in FIGS. 2 to  4 . 
     When it is desired to proceed burning operation, press member  2  is manipulated downwardly so that it compresses the retractable element  6  at the bottom portion thereof, and lap piece  24  drops into guide groove  113 . At this time, connecting rod  32  is unsupported so that retractable element  6  within slidable member  3  extends to horizontally displace, thereby bringing abutting rod  33  to contact stop piece  23 , and connecting rod  32  to displace to above lap piece  24 . Hence, press member  2  cannot bounce back (see FIG.  5 ). At this point, the bottom edge of button member  5  is released from the retaining state due to downward displacement of stop piece  23  so that the pressing operation can be proceeded (see FIGS. 6 and 7) to move the side walls  51 ,  52  and guide piece  53  of the button member  5  towards the burner and compress ignition means (C). At the same time, wall hook  511  will push the sliding plate (B 1 ) to pull up a gas nozzle for supply of gas. The fuel gas passes through an outlet tube (B 2 ) into support means (D) and is ejected via a burning means (E). The fuel gas is then ignited by means of ignition means (C). Then, by pressing button member  5  with one hand, and pressing press rod  43  of retaining member  4  with the other to compress retractable element  6  to displace, the fastening rod  42  at the other end will extend into sliding plate (B 1 ). At this time, by pressing button member  5  slightly to fasten fastening rod  42  to gas means (B), retaining member  4  cannot bounce back. Hence, burning operation can proceed. Particularly, when button member  5  is pressed, wall rod  521  will push trigger rod  35  so that slidable member  3  slightly compresses retractable element  6  to bring connecting rod  32  to once again abut against lap piece  24 . Press member  2  will elevate slightly and is pressed by button member  5  so that it cannot resume its original position. 
     When not in use, button member  5  is pressed again (see FIG. 6) so that fastening rod  42 , due to displacement of sliding plate (B 1 ), is not retained thereby, and can resume its original position due to extension of retractable element  6 . Sliding plate (B 1 ), due to disengagement of retaining member  4 , and by means of ignition means (C) and biasing action of biasing element  7 , displaces outwardly together with button member  5 . At this time, abutting rod  33  in connecting groove  27  gradually moves away from stop piece. When button member  5  resumes its original position, press member  2 , due to extension of retractable element  6 , elevates to the full, with lap piece  24  abutting against connecting rod  32  so that slidable member compress the retractable spring therewithin. Hence, all the components resume their original positions as shown in FIGS. 2 to  4 . At this time, button member  5  is once again retained by press member  2  and hence cannot be pressed. 
     In use, the user must first of all release the safety device of the present invention to make the operation procedure relatively difficult. In other words, in use, the press member has to be pressed so that the slidable member displaces and is positioned prior to pressing of the button member to permit control of ignition and gas supply means. Then, by pressing the button member, with one hand and the retaining member with the other hand to cause it to connect to the gas supply means during the process of displacement and to keep the button member in a constantly pressed state, thereby informing the user that the fuel gas is in a continuous supply state. In addition, after use, the safety device will be automatically locked lest that the user should forget to reset the safety device of the invention to a use state. Furthermore, the press member is disposed below the button member to avoid exposure to children. The complicated release procedure required by the safety device of the invention also helps to prevent accidents caused by children playing with gas burners. Besides, the components of the invention are modularized to facilitate assembly. The invention can be pre-assembled and then installed in a gas burner disclosed in the drawings or in a burner disclosed in the above-mentioned U.S. Pat. No. 5,741,128. 
     Although the present invention has been illustrated and described with reference to the preferred embodiment thereof, it should be understood that it is in no way limited to the details of such embodiment but is capable of numerous modifications within the scope of the appended claims.