US2972445A - Water-flow gas control device - Google Patents

Description

Feb. 21, 1961 E. KEPPEL WATER-FLOW GAS CONTROL DEVICE Filed Aug. 21, 1958v 19 INVENTOR. Z'g Sf Z 6 0 361 904 S ,M

-vice for gas water-heaters.

WATER-FLOW GAS CONTROL DEVICE Ernst Keppel, Remscheid, Germany, assignor to Job. Vaillant K.G., Remscheid, Germany Filed Aug. 21, 1958, Ser. No. 756,507

Claims priority, application Germany Aug. 23, 1957 Claims. (Cl. 236-25) This invention relates to a water-flow gas control de- More particularly, this invention relates to such a device that responds to a dynamic diflerential pressure produced at a constriction point in the water conduit, and in which a slow-ignition jvalve with adjustable throttle cross-section is built into vthe connecting channel leading to the low pressure chamber of the gas valve actuator.

Adjustment of the throttle cross-section of the slow ignition valve has proved to be necessary especially with such apparatus which are equipped with a water flow regulator controlled by the gas control actuator.

As is.

well known, the water fiow regulating valve reaches its operating position only at the end of the opening movement of the gas valve, so that, during this process, the full pressure of the water supply system acts in the dynamic pressure chamber of the differential pressure device. Since the pressure of the water supply system may :largely differ due to local supply conditions, the valve- --opening action produced by the dilferential pressure debeen made adjustable by means of an adjusting screw to be operated by hand. Yet, the hand adjustment, must be for an average condition and will not be correct for extremes. Hence the essential intended advantage of a water-flow regulator, of providing uniform gas valve action, is negatived.

The invention has therefore for its object to provide an improved water-flow gas control device in'which the aforementioned disadvantage is eliminated.

According to the invention, this object is accomplished by provision for adjustment of the throttle cross-section of the slow-ignition valve automatically by means of an adjusting member subject to the differential water pres-, sures working against the action of a spring. The ar-' rangement is advantageously so conceived and designed that the throttle cross-section of the slow-ignition valve is determined by a throttle cone projecting into a Water passage opening, the throttle cone being mechanically connected with a piston on the opposite faces of which act the water pressures.

With this arrangement, the slow-ignition valve can be arranged in either the bottom .portion or the top portion 1 of the water-flow gas control device.

The invention consists in the construction and arrangement of parts that will appear clearly from the following detailed description when' read in conjunction with the accomp'anying drawings in which Figs. 1 to 5 illustrate schematically'two embodiments of the-invention.

Patented F eb.'21',- .1961

2 Drawings Figure 1 shows schematically the arrangement of an automatic slow-ignition valve in the bottom portion of the water-flow gas control device.

Figure 2 represents, in an enlarged scale, the automatic slow-ignition valve conceived and constructed in accordance with the invention.

Figure 3 shows in schematical representation the slowignition valve arranged in the top portion of the waterflow gas control device.

Figure 4 shows a modified form of construction in which the throttle ring used in the embodiments according to Figs. 1 to 3 is substituted by a pot-shaped element.

Figure 5 is a sectional view on a perpendicular plane of part of the structure shown in Fig. 4.

General description Although the following disclosure oifered for public dissemination is detailed to ensure adequacy and aid understanding, this is not intended to prejudice that purpose of a patent which is to cover each new inventive concept therein no matter how others may later disguise it by variations in form or additions or further improvements. The claims at the end hereof are intended as the chief aid toward this purpose, as it is these that meet the requirement of pointing out the parts, improvements, or combinations in which the inventive concepts are found.

Referring to Fig. 1, numeral 1 designates a diaphragm type water dilferential pressure device of conventional design, which may also be called a water deficiency safety'device. The water is supplied to the water difierential pressure device 1 from a cold water supply pipe 2. via a "regulating valve 3. To the lower diaphragm chamber 1 of the water differential pressure device 1 is connected a water service pipe 4 passing through a heat exchanger 6 arranged above the burner 5, pipe 4 being closed at its discharge end by means of a faucet or tap valve 7. A Venturi tube 8 with a connecting channel 9 branching off in such relation to its constriction point to be within the low pressure zone of the Venturi tube forms the'conduit from chamber 1' to the water service pipe 4. The connecting channel 9 leads to the low pressure chamber 1" ofthe water diiferential pressure device 1 via a slowignition valve 10, which in forms chosen for illustration of this invention, will be described in detail in the following.

Automatic throttling A hollow screw 12 with sealing means 13, 13' (see Fig. 2) is screwed into the housing 11 of the s ow-ignition valve 10. A piston 14 sealed by means of a cord or 0 ring sealing ring 14' and carrying a throttle cone 15 sides in the hollow space of screw 12. A throttle ring 16 is inserted in the front end of the screw 12 and is of an internal diameter which permits the throttle cone 15 to project into it. The connecting channel 9 is so arranged in the housing 11 that the water displaced from the low pressure chamber 1" must discharge through lateral bores 17, 17' of the screw 12 and through the throttle ring 16. A channel 18 communicating with the cold water supply pipe 2 and opening up between the sealing means 13, 13 is arranged in the housing 11. The bore 19 provided in the hollow screw 12 has the function of conducting the water supply pressure into the hollow space of the screw 12 behind the piston 14. Piston 14 lies in contact with a spring 20 which is supported by the throttle ring 16 when the piston is moved forward. The water supply pressure available in the supp y pipe 2 governs the entire system if the tap valve 7 is closed. Piston 14, then, is in the end position shown in Fig. 2 and therefore there exists practically a non-throttled communication between the upper diaphragm chamber 1" and the lower diaphragm chamber 1'.

If now the tap valve 7 is opened, the pressure existing in the water passage pipe 4 will drop and this drop together with the action at the Venturi tube will cause a lowering of pressure in tube 9, while, first of all, the substantially full water supply pressure is still effective in the pressure chamber 1. The regulating valve 3 will not yet have reached its restricting position. Consequently, the diaphragm of the water differential pressure device i is subjected to differential pressures and is lifted. The water available in the low pressure chamber 1" must be displaced via the connecting channel 9 regu lated by the slow-ignition valve it A gas valve 21 is opened in well known manner by the diaphragm lift after a certain idle stroke It has been performed. However, in the meantime, piston 14 is displaced by the differential pressures at 9 and is, so that a throttling slot is produced between the throttle ring 16 and the throttle cone 15. This throttling slot so produced throttles in the connecting channel 9 the flow of the water displaced from the low pressure chamber 1'', so that the diaphragm type water deficiency safety device can open the gas valve 21 only slowly. If the differential pressure is high, the force available for acting on the pressure differential device 1 is very great. Then the throttling produced between the throttle ring in and the throttle cone 15 is correspondin ly increased by the advance movement of the piston 14. By appropriate design of the spring 20 and the throttle cone 15 it can be achieved in this mannor that the speed, with which the gas valve 21 is opened, remains almost constant with all water supply pressures and all degrees of opening tap '7. A pressure equalization takes place if tap valve 7 is closed, the water flowing through the connecting channel 9 into the low pressure chamber 1". This equalized pressure permits the spring 20 to cause the piston 14 rapidly to move back into its initial position, so that the diaphragm type water differential pressure device it can respond quickly and the gas valve 21 can close without delay.

Referring now to Fig. 3, which shows a modified form of construction of the device conceived and constructed in accordance with the invention, the slow-ignition valve id is arranged in the top portion of the water differential pressure device. Here, the water displaced from the low pressure chamber 1 flows in reverse direction through the throttle cross-section of the slow-ignition valve 10. It is therefore advantageous to use the form of construction represented schematically in Figs. 4 and 5.

In this form of construction, the throttle ring 16 is substituted by a pot-shaped element 3.6 which, at the one end, has a passage opening 22 and, at the other end, is provided with a bridge 23. Inside the pot-shaped element 16' is arranged a loose annular disk 24 acting as an untight check valve, a slender throttle cone 15' projecting into the central opening of the annular disk 24. If now the water displaced from the low pressure chamber It flows against the annular disk 24, the latter disk is forced toward the right to block passage 22 partially, restricting flow through the passage to a smaller passage or slot 25 remaining between the throttle cone 15 and the annular disk 24. This slot 25 is more or less reduced in size by the forward movement of the piston 14. During the pressure equalization process when tap 7 is closed, when water flows back into the low pressure chamber 1", the annular disk 24 is shifted off the passage opening 22 thereby freeing the full passage cross-section of said opening 22.

With both of the embodiments described above, the bore 19 in the screw 12 can be so designed that the adjustment of the throttle cone E or 15', respectively, takes place with some delay, so that a stroke movement of the differential pressure device corresponding to the idle stroke It can practically take place rapidly still without thereby affecting a throttling in the slow-ignition valve 19 or it) respectively.

The disk 24 is a direction sensitive valving piece which substantially reduces or negatives the throttling effect of cone 15 when the water is flowing into low pressure chamber 1". A similar result could be obtained, at higher cost by a check valve in a passage by-passing the throttling point. With either such arrangement some advantage can be obtained even if the pressure responsive means here represented by piston 14 is only exposed to the full water pressure on its actuating side, the other side being exposed to atmosphere or a sealed air chamber. However, it is preferred, as in the illustrated forms that the piston 14 be responsive to the same differential pressure influencing differential pressure device 1, as this will give the most uniform action when water is flowing from low pressure chamber 1". Also it permits spring 20 to automatically move the throttle to its end position to avoid or greatly reduce throttling when the water flowsinto low pressure chamber 1".

i I claim:

1. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a ga valve and having a low pressure chamber connected through a channel to said constriction to be subject to its pressure reduction, and a slow-ignition valve for throttling the channel characterized by having means controlling the slow-ignition valve and exposed to the full water pressure to be urged by it in a direction to cause it to increasingly throttle the channel, but biased in the opposite direction, and effective at least during flow from the low pressure chamber, to throttle the channel with a throttling effect which increases in correlation, in part at least, to the full water pressure.

2. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valveand .having a high pressure chamber subjected to full water pressure and a low pressure chamber subjected to the reduced water pressure provided by said constriction, a channel through which water must flow as said differential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means controlling the slow-ignition valve and exposed to the full water pressure to be urged by it in a direction to cause it to increasingly throttle the channel, but biased in the opposite direction, and effective at least during contraction of the low pressure chamber, to increasingly throttle the channel with a throttling effect which increases in correlation to at least one of the water pressures.

3. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valve and having a .high pressure chamber subjected to full water pressure and a low pressure chamber subjected to the pressure reduction of said constriction, a channel through which water must flow as said differential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means for controlling the slow-ignition valve for throttling said channel, at least during contraction of the low pressure chamber, in correlation to at least one of the differential pressures leading to said pressure chambers to reduce the variations in speed of response of the differential pressure device to varying pressure influences.

4. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a difierential pressure device for controlling a gas valve and having a high pressure chamber subjected to full water pressure and a low pressure chamber subjected to. the pressure reduction of said constriction, a channel through which water must flow as said differential pressure device operates, and a slowignition valve for throttling the channel characterized by having means for controlling the slow-ignition valve for throttling said channel, at least during contraction of the low pressure chamber, in correlation to at least one of the differential pressures leading to said pressure chambers to reduce the variations in speed of response of the differential pressure device to varying pressure influences; said slow-ignition valve including a throttle cone projecting into an opening forming part of the channel and a piston exposed on one side to one of the differential water pressures and connected to the cone to move it for greater throttling when the piston is moved by a pressure change in the direction tending to increase the differential of pressures.

5. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valve and having a high pressure chamber subjected to full water pressure and a low pressure chamber subjected to the pressure reduction of said constriction, a channel through which water must flow as said differential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means for controlling the slow-ignition valve for throttling said channel, at least during contraction of the low pressure chamber, in correlation to at least one of the differential pressures leading to said pressure chambers to reduce the variations in speed of response of the differential pressure device to varying pressure influences; and a direction sensitive valve member associated with the slow-ignition valve to substantially reduce its throttling effect when the low pressure chamber is expanding.

6. A water flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valve and having a high pressure chamber subjected to full water pressure and a low pressure chamber subjected to the pressure reduction of said'constriction, a channel through which water must flow as said difierential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means for controlling the slow-ignition valve for throttling said channel, at least during contraction of the low pressure chamber, in correlation to at least one of the differential pressures leading to said pressure chambers to reduce the variations in speed of response of the differential pressure device to varying pressure influences; said slowignition valve including a throttle cone projecting into an opening forming part of the channel and a piston exposed on one side to one of the differential water pressures and connected to the cone to move it for greater throttling when the piston is moved by a pressure change in the direction tending to increase the differential of pressures; and a direction sensitive valve member associated with the slow-ignition valve in the form of a movable disk surrounding the throttle cone and movable along it to substantially reduce its throttling effect when the low pressure chamber is expanding.

7. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valve and having a high pressure chamber subjected to full water pressure and a low pressure chamber subjected to the pressure reduction of said constriction, a channel through which water must flow as said differential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means for controlling the slow-ignition valve for throttling said channel, at least during contraction of the low pressure chamber, in correlation to at least one of the differential pressures leading to said pressure chambers to reduce the variations in speed of response of the differential pressure device to varying pressure influences; said slow-ignition valve being of reduced throttling effectiveness when the low pressure chamber is expanding.

8. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valve and having a high pressure chamber subjected to full water pressure and a'low pressure chamber subjected to the pressure reduction of said constriction, a channel through which water must flow as said differential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means for controlling the slow-ignition valve for throttling said channel, at least during contraction of the low pressure chamber, in correlation to at least one of the differential pressures leading to said pressure chambers to reduce the variations in speed of response of the differential pressure device to varying pressure influences; said device including means restricting the speed of adjustment of the slow-ignition valve to retard its throttling effect to enable the differential pressure device to move rapidly in initially taking up lost motion.

9. A water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valve and having a high pressure chamber subjected to full water pressure and a low pressure chamber subjected to the pressure reduction of said constriction, a channel through which water must flow as said differential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means controlling theslow-ignition valve and exposed to the full Water pressure to be urged by it in a direction to cause it to increasingly throttle the channel, but biased in the opposite direction, and urged in said opposite direction by water pressure subjected to the pressure reduction of said constriction, and effective at least during contraction of the low pressure chamber, to increasingly throttle the channel in correlation with the differential water pressure to which the differential pressure device is subjected.

10. A Water-flow gas control device including means forming a main water flow passage having a pressure reducing constriction for reducing pressure upon flow therethrough, a differential pressure device for controlling a gas valve and having a high pressure chamber subjected to full water pressure and a low pressure chamber subjected to the pressure reduction of said constriction, a channel through which water must flow as said differential pressure device operates, and a slow-ignition valve for throttling the channel characterized by having means controlling the slow-ignition valve and exposed to the full water pressure to be urged by it in a direction to cause it to increasingly throttle the channel, but biased in the opposite direction, and urged in said opposite direction by water pressure subjected to the pressure reduction of said constriction, and efiective substantially only during contraction of the low pressure chamber, to increasingly throttle the channel in correlation with the differential water pressure to which the differential pressure device is subjected.

References Cited in the file of this patent UNITED STATES PATENTS 2,258,590 Merten Oct. 14, 1941 2,274,017 Weber Feb. 24, 1942 2,795,380 Donges June 11, 1957 FOREIGN PATENTS 563,219 Germany Oct. 13, 1932

Images