Metering head

[0002] The drawings show:

[0003] FIG. 1 a cross-sectional view of a metering head according to the present invention with a metering valve and two outlets and with the head inlet connected with a gas bottle;

[0004] FIG. 2 a cross-sectional view of the metering head shown in FIG. 1 with the cross-section taken at an angle of 90° to the cross-section shown in FIG. 1;

[0005] FIG. 3 a cross-sectional view of a metering head according to the present invention with two metering valves arranged in a longitudinal direction of a gas bottle with which the metering head is connected, and two outlets;

[0006] FIG. 4 a cross-sectional view of a the metering head shown in FIG. 3 with the cross-section taken at an angle of 90° to the cross-section shown in FIG. 3;

[0007] FIG. 5 a cross-sectional view of a the metering head according to the present invention with two metering valves arranged transverse to a longitudinal direction of a gas bottle, with which the metering head is connected, and two outlets;

[0008] FIG. 6 a cross-sectional view of a the metering head shown in FIG. 5 with the cross-section taken at an angle of 90° to the cross-section shown in FIG. 5;

[0009] FIG. 7 a view showing the metering head as shown in FIG. 5 at an increased scale;

[0010] FIG. 8 a view showing the metering head as shown in FIG. 6 at an increased scale; and

[0011] FIG. 9 a partial cross-sectional view showing the region of inlet and outlet of the metering valve.

[0012] In the embodiment of a metering head according to the present invention, which is shown in FIG. 1, the metering head 1 is fixedly secured on a gas bottle 2 containing liquified fuel gas. For securing of the metering head 1 on the bottle 2, there are provided, in the lower region of the metering head 1, resilient hooks 3 which extend downwardly from the lower portion of the metering head 1 and engage beneath a circumferential head 4 of the upper end side of the gas bottle 2.

[0013] Inside of the metering head 1, there is located a metering valve 5 a longitudinal axis 6 of which coincides with a longitudinal axis 7 of the gas bottle 2. A ventilation chamber (not shown) of the metering valve 5 has its inlet side connected with hollow pin 8 which extend from a bottom 9 of the metering head 1. When the metering head 1 is secured on the gas bottle 2, the hollow pin 8 engages in the outlet valve of the gas bottle 2, opening the valve. Liquified gas flows from the gas bottle 2 through the hollow pin 8 into a channel 10 of the metering valve 5, reaching the metering chamber of the metering valve 5. The metering chamber of the metering valve 5 is constantly filled through its inlet with the fuel gas when the metering head 1 is secured on the gas bottle 2 and is not actuated. The outlet of the metering chamber of the metering valve 5 remains closed and becomes open only when needed, with the inlet of the metering chamber being closed for a short time.

[0014] The outlet of the metering chamber of the metering valve 5 is connected with an annular channel 12 by an outlet channel 11 of the metering valve 5 and a connection channel 13. Two transverse channels 14 and 15 open, respectively, into two spout-out nozzles 16 and 17.

[0015] The annular channel 12, the connection channel 13, and the transverse channels 14 and 15 are all located in a cap portion 18 of the metering head 1. The lower region of the cap portion 18 circumscribes the metering head chamber containing the metering valve 5 and the bottom member 19 of the metering head 1 which carries the metering valve 5. The bottom member 19 is displaceable along the longitudinal axis 6 of the metering valve 5. The hooks 3 and the hollow pin 8, which were discussed above, are provided on the bottom member 19 and, e.g., are formed integrally therewith.

[0016] The outlet channel 11 of the metering valve 5 extends along the metering valve axis 6 and is dischargeable in a correspondingly extending portion of the connection channel 13. When the gas bottle 2 is lifted and the bottom member 19 is pushed into the cap portion 18, an outer flange 20 of the metering valve 5 is lifted, which results in the inlet valve of the metering valve 5 being closed and the outlet valve of the metering valve 5 being open, with a metered volume of the liquefied fuel gas reaching the spout-out nozzles 16, 17. The spout out. nozzles 16, 17 are located in cylindrical members 21, 22 connected with the cap portion 18. The cylindrical members 21, 22 are provided with outer sealing rings 23, 24, respectively, and therewith are sealingly inserted in corresponding openings formed in the wall of a combustion chamber of a setting tool. The cap portion 18 is fixedly connected to this wall. The longitudinal axes 25, 26 of the spout-out nozzles 16, 17, which form outlets of the metering head 1, extend transverse to the longitudinal axis 6 of the metering valve 5. Upon lowering of the gas bottle 2, the bottom member 19 which is fixedly connected with the gas bottle 2 as described above, also moves downwardly. The downward movement of the bottom member 19 results in closing of the outlet of the metering chamber 5 and opening of its inlet, and the metering chamber of the metering valve 5 is again filled with the liquified fuel gas.

[0017] FIGS. 3-4 show a second embodiment of the metering head according to the present invention. In FIGS. 3-4, the elements of the metering head 1 identical with those shown in FIGS. 1-2, are designated with the same reference numerals and will not be further described.

[0018] The embodiment of the metering head 1 shown in FIGS. 3-4 differs from that shown in FIGS. 1-2 in that the metering head 1 has two metering valves 5aand 5bthe longitudinal axes 6aand 6bof which are spaced from each other and extend parallel to the longitudinal axis 7 of the gas bottle 2. The metering head 1 is fixedly secured on the gas bottle 2, and the bottom member 19 is not displaceable relative to the cap portion 18. The metering chambers 27a, 27bof the two metering valves 5a, 5bare thereby permanently and simultaneously filled with the liquified fuel gas through the hollow pin and the channel 10 provided in the bottom number 19. The inlets 30a, 30bof the metering chambers 27a, 27bof the valves 5a, 5bremain open, as it, particularly can be seen in FIG. 3.

[0019] Outlets 28aand 28bof the metering chambers 27a, 27bof the metering valves 5a, 5bare still closed in the position shown in FIG. 3. The outlets 28aand 28bare connected, respectively, via the connection channels 11a, 11b, with transverse channels 29a, 29bwhich, in turn, open into nozzles 16, 17, respectively. The connection channels 11a, 11bare connected with the transverse channels 29a, 29bat the edges of the transverse channels 29a, 29b. When with the stationary cap member 18, the gas bottle 2 is pushed in the direction toward the cap member 19, the bottom member 19 is displaced partially thereinto. This results in closing of the inlets 30a, 30bof the metering chambers 27a, 27band in opening of the outlets, 28a, 28b. This provides for the flow of the liquified fuel gas toward the nozzles 16, 17. Upon release of the gas bottle 2, the bottom member 19 moves out of the cap member 18 which results in closing of the outlets 28a, 28bof the metering chambers 27a, 27band in opening of the respective inlets 30a, 30b. With this process, the members 21, 22, in which the nozzles 16, 17 are located, are fixedly secured in the wall of the combustion chamber of the setting tool, whereby the cap member 18 is fixedly positioned.

[0020] The structure of the metering valve itself will be discussed in more detail below with reference to FIG. 9.

[0021] A third embodiment of a metering head 1 according the present invention is shown in FIGS. 5-8. In this embodiment, the metering valves 5a, 5bare so arranged that their longitudinal axes 6a, 6bextend transverse to the longitudinal axis 7 of the gas bottle 2. In FIGS. 5-8, the elements of the metering head 1 identical with those of FIGS. 1-4 are again designated with the same reference numerals and will not be discussed in detail.

[0022] In the embodiment shown in FIGS. 5-8, the metering chambers 27a, 27bof the metering valves 5a, 5bare connected, as in the previous embodiments, with the hollow pin 8 via the channel 10. The metering chambers 27a, 27bbecome filled with the liquified fuel gas when the outlet 28a, 28bare not in communication with the metering chambers 27a, 27band are quali closed. In this case, no fuel gas flows to the nozzles 16, 17. The outlet channels 11a, 11b, which are connected with outlets 28a, 28c, at their rear end, open into a front plate 18aof the cap member 18, with the channels 11a, 11bbeing sealed relative to the plate 18.

[0023] The outlet channels 11a, 11bare connected with the nozzles 16 and 17. The cylindrical members 21, 22, which house the nozzles 16, 17, respectively, are formed integrally with the front plate 18aand have inner channels 16a, 17awhich lead from the nozzles 16, 17 to the outlets channels 11a, 11b. The connections between the front plate 18aand the outlet channels 11a, 11bare fluid-tight, at least in the edge region of the outlet channels 11a, 11b. The front plate 18aextends transverse to the longitudinal axes 6a, 6bof the metering valves 6a, 6b, with the cylindrical members 21, 22 being inserted in respective openings in the combustion chamber wall. The bottom member 19 is fixed to the gas bottle 2 and is displaceable toward the front plate 18ain accordance with the operational cycle of the setting tool the combustion chamber of which has to be filled with the fuel gas through the nozzles 16, 17. The operation of the drive mechanism of the bottom member 19 along the axes 6a, 6bor 25, 26 can be controlled by the control unit of the setting tool.

[0024] With the bottom member 19 remaining stationary, i.e., in position in which it is not pushed toward the front plate 18, the liquified fuel gas flows from the gas bottle 2 into the metering chambers 27a, 27bvia the hole pin 8 and the channel 10. The inlets 30a, 30bare open, as can be seen in FIG. 8. The outlets 28a, 28bare located outside of the respective metering chambers 27a, 27band are closed. Springs 31a, 31c, which are supported against the bottom member 19, bias the valve tappets 32a, 32bpermanently into a position in which the inlets 30a, 30bremain open. On the other hand, the outlet channels 11a, 11b, which sit on the valve tappets 32a, 32b, are supported against the front plate 18a. When the bottom member 19 is pushed toward the front plate 18a, the measuring chamber housings 33a, 33b, which are connected with the bottom member 19, are displaced therewith and close respective inlets 30a, 30b. The housings 33a, 33bare displaced past the outlets 28a, 28 so the later are located inside the respective metering chambers 28a, 28b. The fuel gas, which fills the metering chambers 27a, 27b, flows therefrom via the outlets 28a, 28band the outlet channels 11a, 11bto the nozzles 16, 17. Upon release of the bottom member 19, the measuring chamber housings 33a, 33bmove downward, closing the outlets 28a, 28b. The springs 31a, 31bretain the valve tappets 32a, 32bin a position in which the inlets 30a, 30bremain open.

[0025] FIG. 9 shows an axial cross-sectional view of the metering valve. The valve tappet 32acarries a cylinder 37 provided with the outlet channel 11aand the transverse channel defining the outlet 28a. The housing 33adefine the metering chamber 27aand is provided with a resilient sealing 34 in which the valve tappet 32ais received. A flange 20aholds the housing 33ain engagement with the bottom member 19. The free end of the outlet channel 11ais in contact with the front plate 18aof the cap member 18. The cylinder 37, in which the outlet channel 11ais formed, is biased against the front plate 18aby the spring 31asupported against the bottom member 19 and acting on the valve tappet 32a.

[0026] FIG. 9 shows a position of the metering chamber housing 33arelative to the outlet channel 11a, in which the transverse outlet channel 28ais located inside of the metering chamber 27a. In this position, the outlet 28ais open so that the fuel gas, which fills the metering chamber 27a, can flow through the channels 28aand 11a. Upon release of the bottom member 19, the flange 20ais pulled relative to the valve tappet 32aor the outlet channel 11arearwardly, with the flange 20abeing pulled, with respect to the transverse channel 28a, leftwards until it is located behind the outlet 28a(the transverse channel). Thereby the outlet 28abecomes closed. Simultaneously or shortly thereafter, the resilient sealing 34 of the metering chamber housing 33ais displaced over the chambered rear edge 35 of the cylinder 37, whereby a clearance is formed between the edge 35 and the resilient sealing 34 through which the fuel gas can flow into the chamber 27athrough the inlet 30awhich is defined by the formed clearance. The downward movement of the flange 20ais limited by a stop 36 provided on an outerside of the cylinder 37.

[0027] Though the present invitation was shown and described with references to the preferred embodiments, such are merely illustrative of the present invention and are not to be construed as a limitation thereof and various modifications of the present invention will be apparent to those skilled in the art. It is therefore not intended that the present invention be limited to the disclosed embodiments or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims.