Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to a gas switch, and more particularly to a gas switch that is capable of achieving smooth adjustment of fire in different intensity from strong fire to weak fire. 
     2. Description of the Related Art 
     Conventionally, the method used in a gas switch to adjust fire intensity is often achieved by using a drive rotating shaft to drive a fastener inside the switch body to rotate, so as to make air ports or guide slots in different diameter on the fastener correspond with air intake holes inside the switch body respectively. In such a way, the gas switch will generate different fire intensity as the drive rotating shaft revolves to release gas of different flows. Since usually there is space between the air ports or guide slots in different diameter, the cross section area for gas flows will not be evenly altered in the process of adjusting different air ports or guide slots to correspond with the air intake. As a result, it is impossible to achieve smooth and linear changes in the course of adjusting fire among different intensities, thus further making it impossible for users to finely adjust the fire intensity of gas stoves effectively. 
     To solve this problem, someone designed a kind of gas switches able to adjust fire intensity. On the fastener of such gas switch, only one guide slot and gas guide hole is installed and connected with the internal through hole, and the guide slot is joint with the gas intake hole. So, the slide guide component built on the drive shaft rod can work with the undulant guide to make the drive rotating shaft generate axial displacement as the shaft rotates, thus changing the space between one end of the fastener rod and the air outlet hole and further adjusting the cross-section area for gas flows. By doing so, it will achieve relatively smooth changes among fires of high, medium and low intensities. 
     While the aforesaid design of gas switches can lead to smooth changes of fire in different intensity, its slide guide component in the shape of a round rod can be built into the slot at one end of the fastener, in addition to working with the guide. Therefore, the drive rotating shaft can drive the fastener to rotate as it revolves. In another word, the slide guide component serves not only as a structure to control axial displacement of the drive shaft rod, but also as a component to rotate the fastener. However, the slide guide component is liable to wear and tear due to friction with walls of the fastener slot in the long period and effect of payloads generated in driving the fastener to rotate since it is a tiny component in the shape of a round rod. Moreover, in the cases where the slide guide component is worn out, control error will occur in the process of working with the guide to make the drive shaft rod generate axial displacement, which, in return, will lead to the result that fires in different intensities cannot be smoothly changed in a real way. Therefore, it is obvious that such gas switches still have defects in practical applications. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a gas switch capable of adjusting fire intensity finely, which can eliminate the above-mentioned shortcoming that slide guide components of gas switches are subject to wear and tear, and can really achieve smooth and linear changes of fires in different intensity, thus achieving better effect of fine adjustment of fire intensity. 
     According to the objective of the present invention, the present invention provides a gas switch capable of adjusting fire intensity finely, comprising a switch body which includes a base and a cover. In the base, there is a conical valve chamber with an opening at one end and a gas intake hole as well as a gas outlet hole connected through the valve chamber, while the cover is placed at the side opposite to the valve chamber of the base, and a guide is installed inside the cover; a valve set, which is installed and rotates inside the valve chamber and includes a hollow valve and a pilot valve. On the valve, there are several air ports and inside it, there is a control port. The pilot valve can move elastically inside the valve with one control structure installed at one end of it, which always closes the control port when the pilot valve is not pushed; a drive component installed on the cover, which contains a rotating rod that rotates round and moves along the same shaft of the valve set; a guide rod installed on the rotating rod and leans on the guide; a regulating block which can move along the rotating rod and is closely connected with the pilot valve; and a connecting component for linking the drive component with the valve set flexibly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following paragraphs, an example of the preferred embodiment of the present invention is given with reference to the accompanying drawings to further describe the present invention in detail as follows, wherein: 
         FIG. 1  is a schematic view of a first preferred embodiment of the present invention; 
         FIG. 2  is a perspective view of the cover and drive component of the first preferred embodiment of the present invention; 
         FIG. 3  is a sectional view along the  3 - 3  line of  FIG. 2 ; 
         FIG. 4  shows schematically an act according to one example of the preferred embodiments of the present invention, which indicates the state in which the drive component rotates by 90 degrees; 
         FIG. 5  is a gas flow curve diagram of the first preferred embodiment of the present invention; 
         FIGS. 6A-6D  show a schematic view of the first preferred embodiment of the present invention, illustrating changes in the relationship between the guide rod and the guide following rotation of the drive component; and 
         FIG. 7  is a schematic view of a second preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Refer to  FIGS. 1 to 3 , which show that the gas switch  10  comprises a switch body  12 , a valve set  14 , a drive component  16  and a connecting component  18  according to one example of the preferred embodiment of the present invention. 
     The switch body  12  consists of a base  22  and a cover  24 . Inside the base  22 , there is a conical valve chamber  26  with an opening at one end and a gas intake channel  28  and a gas outlet channel  30 , both of which are connected through the conical valve chamber  26 , while the cover  24  is placed at one side of the base  22 , and at the side opposite to valve chamber  26 , there is a containing hole  31  and a guide  32 . And there is an inclining section  34 , a first flat section  36 , a declining section  38  and a second flat section  40  that reaches out around the containing hole  31 . The inclining section  34  gradually approaches the valve set  14  in a inclined way, while the declining section  38  moves gradually faraway from the valve set  14  in a inclined way. 
     The valve set  14  can be installed rotatably inside the valve chamber  26  and includes a valve  42 , a pilot valve  44 , a leakage stopping component  46  and a spring  48 . And the valve  42  has a conical switch body  50  and a protrusive ring  52  that projects above one end of the switch body  50 , and there is a joint structure  53  between the switch body  50  and the protrusive ring  52 . On the axis of the switch body  50 , there is a through channel  54  divided into one part of big diameter  56  and the other part of small diameter  58 , and a control port  60  is formed in the place where the part of big diameter  56  and the other part of small diameter  58  are connected. Besides, on the surface of the switch body  50 , a guide slot  62  is installed to connect the gas intake channel  28  and a gas intake hole  64  is set to connect the guide slot  62  with the part of small diameter  58 . The pilot valve  44  passes through the channel  54  of the switch body  50 , and includes a rod section  66  and a pushing control section  68  which is placed at one end of the rod section  66  to correspond with the control port  60 . The leakage stopping component  46  is equipped with an O-shaped ring and a circular gasket placed inside the joint structure  53  on the outward side of the rod section  66 . The spring  48  is fixed by a clamping component  74  at the external side of the rod section  66  and leans against the gasket, so that the control section  68  can seal the control port  60  when no pushing force is applied to the pilot valve  44 . 
     The drive component  16  is installed on the cover  24  and comprises a rotating rod  76 , a guide rod  78  and a regulating block  80 , and can rotate and move through the containing hole  31  of the cover  24  to reach into the interior of the protrusive ring  52  of the valve  42 . On the rotating rod  76 , there is an axle hole  82  combined with one end of the pilot valve  44  to form an internal thread  84 , so as to allow the regulating block  80  to be movably installed inside and lean against the pilot valve  44 . The guide rod  78  is a round rod fixed on the rotating rod  76  and close to the surface of the guide  32 , so as to make it move on the surface of the guide  32  when the rotating rod  76  begins to revolve, thus causing the rotating rod  76  to generate axial displacement due to undulations on the surface of the guide  32 . The regulating block  80  is a bolt, and there is a connecting component  86  at one end of the bolt close to the pilot valve  44 . The connecting component  86  presents a roughly conical cross section in order to be connected with the valve  44  with low friction. 
     The connecting component  18  consists of two circular contact plates  88  and  89  and a spring  90 . The two contact plates  88  and  89  surround the rotating rod  76  and the protrusive ring  52  of the valve  42 , while the spring  90  is linked with the two contact plates  88  and  89  at the external side of the rotating rod  76  and protrusive ring  52 , so that the valve set  14  can be rotated by the rotating rod  76  as it revolves. 
     In addition, the gas switch  10  also includes a digital ignition  19  commonly seen in ordinary gas switches, which is installed on the cover  24 . 
     The gas switch  10  of the present invention has the features as follows: 
     When the drive component  16  is rotated, the guide rod  78  will move along the surface of the guide  32 , which will further cause the rotating rod  78  to generate axial displacement as there are undulations on the surface of the guide  32 . This will press the pilot valve  44  and change the space between the control section  68  and the control port  60 , thus altering the fire intensity smoothly. 
     To put it in detail, as shown in  FIG. 4  and the A line of  FIG. 5 , when the gas switch  10  performs ignition actions (generally rotate the rotating shaft by 90 degrees), the drive component  16  will be rotated, pressing the guide rod  78  to move to the first flat section  36  along the inclining section  34 . So the drive component  16  will move towards and push the pilot valve  44 , causing the control section  68  not to seal the control port  60  any more. As a result, gas will be discharged through the guide slot  62  and gas intake hole  64  into the part of small diameter  58 , and further released out of the gas outlet channel  30  through the part of big diameter  56  for burning, as shown in  FIG. 4 . At this moment, the space between the control section  68  and the control port  60  reaches its maximum, hence the gas flows will reach its maximum and the fire intensity will be the highest, as shown in  FIGS. 6A and 6B . 
     Yet as the drive component  16  continues to be rotated by more than 90 degrees, the guide rod  78  will pass over the first flat section  36  and slide into the declining section  38 , as shown in  FIG. 6C . In such cases, the drive component  16  will gradually move outwards due to effect of tensile force of the spring  90  in the connecting component  18 , causing the pilot valve  44  to move outwards, too, due to effect of tensile force of the spring  48 . This will lead to reduced space between the control section  68  and the control port  60 , as a result, the gas flows will gradually reduce and the fire intensity will grow weaker. When the drive component  16  is rotated by 270 degrees, the guide rod  78  will slide onto the second flat section  40  at the end of the declining section  38 , and the fire intensity will be kept at the lowest level, as shown in  FIG. 6D . 
     Secondly, when the gas switch  10  is kept in the position of ultimate fire intensity (lowest fire intensity), the fire intensity cannot be changed or adjusted finely, because the space between the control section  68  and the control port  60  will not change any more. At this point, tools may be used to rotate the regulating block  80  so as to make it protrude or retract slightly, and then the pilot valve  44  will move backwards or forwards slightly due to effect of the pushing force from the regulating block  80 . In this way, the space between the control section  68  and the control port  60  can be enlarged or shortened slightly to increase or reduce gas flows, thus making the fire intensity become stronger or weaker and eventually achieving fine adjustment of fire intensity, as shown in the B and C lines in  FIG. 6 . 
     As shown in  FIG. 7 , it may also be decided in the present invention that the cross section of the connecting component  86  of the regulating block  80  is roughly like a curve, in order to keep it also in the state of low-friction contact with the pilot valve  44 . This will prevent the cases where the regulating block  80  drives the pilot valve  44  to rotate as the drive component  16  rotates the valve set  14  and ensure that the structure works normally. 
     It can be seen from the above descriptions that the gas switch described in the present invention relies on the synergy of the guide rod and the guide to make the drive component and the pilot valve move axially and very smoothly, and further cause linear changes in the process of adjusting firepower in different intensity, thus achieving good results in fine adjustment of fire intensity. Besides, the valve set is rotated because of the effect of the driving force from the drive component, not because of that from the guide rod; therefore the guide rod is not liable to wear and tear, thus securing smooth and linear change in the process of fire intensity adjustment. Moreover, the regulating block can achieve the effect of adjusting the final fire intensity of the gas switch.

Technology Category: 4