US1719162A - Acetylene-gas generator - Google Patents

Description

July 2, 1929. c. w. BECK ACETYLENE GAS GENERATOR I Filed Jan. 23, 1922 3 Sheets-Sheet 2 July 2, 1929. c. w. BECK 1.719.162

ACETYLENE GAS GENERATOR Filed Jan. 23, 1922 3 Sheets-Sheet 3 Patented July 2, 1929.

PATENT OFFICE.

CHARLES W. BECK, F DETROIT, MICHIGAN.

AGETYLENE-GAS GENERATOR.

Application filed January 23, 1922. Serial No. 531,217.

This invention relates to improvements in acetylene gas generators.

lt is the practice in machines of this kind to deliver the carbide, in intermittent charges to the water in the tank, and permit the same to pass to the bottom of the tank into the sludge. This method is highly ob ect1onable because in operating in this way, experlence has shown that unspent portions of the charge accumulate in the sludge and often times has resulted in excess pressures and serious explosions. It is the object of the present invention to increase the safety of such apparatus; to provide for holding each charge of carbide in suspension in the body of water free from the residue of previous charges, until it is fully spent, the dangerous accumulation of carbide in the sludge in the bottom of the tank, before referred to, being thus avoided and the efficiency of the apparatus materially increased.

An important novel characteristic of the invention also resides in the specific carbide feeding means provided whereby increased efficiency in the feeding of the material is obtained and agas tight seal is provided between the tank and feed opening of the carbide chamber.

The invention, with other objects and advantages thereof, and the part1cular construction, combinations and arrangements of parts comprising the same, will be understood from the following detailed description, when considered in connection with the accompanying drawings, forming part here of, and illustrating embodiments of the invention. 1

in the drawings.

Figure 1 is a vertical section of an apparatus constructed in accordance with the present invention.

Fig. 2 is a detail longitudinal section through the feed tube andscrcw.

Fig. 3 is a detail transverse section through the feed tube and screw.

Figure l is a side elevation with parts shown in dotted lines.

Figure 5 is a top plan view with parts shown in dotted lines.

Fig. 6 is a detail view on an enlarged scale, of part of the feeding mechanism.

Fig. 7 is a detail view of the spring retaining means associated with the brake lever.

Fig. 8 is a detail view of the lost motion 1connection of the operating rod and the brake ever.

Fig. 9 is an end elevation, on an enlarged scale, of the shaft positioning means.

Fig. 10 1s a vertical section of a modified construction.

Fig. 11 is a detail longitudinal section, on

an enlarged scale, through the feed tube and screw illustrated in Figure 10.. The invention eomprehends carbide feedng means controlled by the gas pressure, and 1n combination therewith a screen, perforated shelf or tray arranged in the tank to receive the'carbide from the feeding means and to hold the same in a layer in suspension in the body of water near the surface thereof, said screen, perforated shelf or tray, being adapted to be shifted to dump any foreign matter from the spent charge and to present a fresh surface free from the residue of other spent charges, to-receive the following charge, pro- 'VlSlOll being thus made whereby each charge of carbide is held suspended in the body of water near the surface thereof. 7

While specific embodiments of the invention are illustrated in the drawings, it will of course be understood that changes and variations in the particular constructions shown, and the carrying out of the invention in other forms, as will appeal to those skilled in the art and falling within the scope of the appended claims may be practiced without departing from the spirit of the invention.

Referring to a detail description of the drawings, 1 designates a conventional form of tank, having a water supply pipe 1. 2 designates the carbide chamber or receptacle at the top of the tank 1 having a hopper bottom 3 with an outlet part 4 and feed tube 5, the latter having an outlet opening 6 leading into the tank 1. The outlet part 4 has offset or angularly disposed portions 4*, 4", and within the receptacle 2 over the outlet portion 4 is a cylindrical partition 7, these constructions being adapted to prevent packing or wedging of the material above and within the outlet part 4:. 9 and 10 are gas outlet pipes, the pipe 9 leading from the upper part of the tank to the upper portion of the carbide chamber 2, and the pipe 10 leading therefrom i to the usual gas hell, (not shown) or directl v to the service line. 11 designates a filling opening, and 11' is a removable screw plug or cover therefor.

' provide a. gas tight packingor seal between the tank 1 and the feed opening 4 of the carbide chamber'. 13 designates the shaft of the feed screw su ported in bearings 14, and 15 on the feed tube. In the articular construction shown, the main rigid portion 17 of the blade of the feed screw is providedsvith a recess 18 at one side thereof, and seatedin the recess and projecting beyond the periphery of the main rigid blade portion is a strip of flexible material 19. The strip 19 may be formed of soft rubber, leather or any other material suitable for the purpose, soft rubber being preferred. The strip 19 is supported and tightly held in place within the recess against the side wall thereof by a clamping stri 20 ofmetal or other suitable material, sai strip 20, which is conveniently formed in sections, as shown, being secured to the mam rigid portion 17 of the feed screw by screws or e uivalent fastening means 21. In order to a ditionally guard against the escape of moist gas from the tank 1 into the discharge opening 4 of the carbide chamber through the feed tube 5, said tube is provided with a valve 5', said valve being in the form of a plate hinged at its upper portion to an upper part of the tube, as shown, the valve being yieldablymaintained in closed position against the end of the tube by gravity or other means.

Referring particularly to the construction illustrated Figures 1 to 6, of the drawings, the feed screw is; driven by a spring motor 24 mounted on the carbide chamber 2. The motor 24'whieh may be of any convenient construction is operatively connected with the feed screw through the medium of a vertical shaft 25 having pinions 26, 27 at opposite ends meshing respectively with a pinion 28 on the feed screw shaft 12, and a pinion 29 on the drive shaft 30 of the motor. Pressure operated means for controlling the operation of the motor is provided. 31 designates a brake disk on a shaft 32 connected by gears 33 with the driving shaft of the motor, and 34 is a brake lever provided with a shoe 34' to cooperate with the brake disk 31.

The brake lever 34, which is pivoted at one end at 35, is connected by a rod 36 with a diaphragm 37 arranged in the top of the tank 1 to be actuated by the pressure of the gas. At the outer side of the diaphragm 37 is a coiled spring 38 arranged to exert pressure inwardly on the diaphragm, the force of the spring 38 beingssuch as to hold the diaphragm against outward movement until the pressure of the gas in the tank reaches a predetermined degree. The spring 38 is arranged within an exteriorly threaded tubular nut 39 which adjustably engages a threaded bushing 40 on the cap 41 that extends over the diaphragm 37, said tubular nut being provided with an opening 39 in its top, through which the rod 36 extends, the rod 36 slidably engaging the walls of the opening which form a support and guide for the rod. As will be understood by turning the tubular nut 39 the tension of the spring 38 can be adjusted. When the diaphragm is raised or elevated by the gas. pressure, the brake lever 34 will be raised to carry its shoe 34, into contact with the brake disk 31 as indicated in Figure 4 of the drawings, and the motor will be held locked against operation until the pressure in the tank becomes reduced, the diaphragm being then forced downwardly by the coiled spring 38 carrying with it the rod 36, the brake shoe 34 being moved out of engagement with the brake disk 31, and the motor permitted to operate to drive the screw to feed carbide from the carbide receptacle to the tank.

The means for receiving the carbide from the feed tube 5 and for holding the same in suspension in the body of water in the tank, comprises a screen, perforated shelf or receptacle supported for rotation in the upper part of the tank, said shelf or receptacle having two compartments disposed diametrically opposite to each other with relation to its axis of rotation, the shelf or receptacle being adapted to be turned to dump the residue therefrom, and the arrangement being such that when one side thereof or one of the compartments of the receptacle is inverted to dump the same, the other side or compartment is brought to horizontal position just below the level of the. water in a position to receive a fresh charge from the carbide receptacle. The perforated shelf or tray is shown as consisting of a single bottom wall or portion 41 with side wall portions 4-2, 43, extending from each side of the bottom wall 41, providing oppositely disposed compartments. The perforated shelf or receptacle is shown supported for rotation by shaft sections 44, 45 extending from opposite ends of its bottom wall or portion 41", and engaging bearings 46, 47, on the wall of the tank.

The operating means for the carbide supporting tray or receptacle, in this particular instance, is shown as comprising an extension 36' of the rod 36, provided at its lower end with a spring pressed rack or pawl 49 and a ratchet wheel 50 fixed on the shaft section 45, the arrangement being such that upon nection is provided between the upper end of the rod 36 and the brake lever 34. In the particular construction illustrated in the drawin the rod is provided with an elongated s 0t 36. For purposes of adjustment the rod is also shown provided with a screw 36". 51 designates a spring which serves to maintain the brake lever 34 in its uppermost position until moved downwardly by the rod 34 during the latter part of the downward movement thereof, said spring 51 being secured at one end to the motor casing and having its opposite end bearing laterally against one side of the brake lever, as shown, (see Figure 7).

For the purpose of lnsurlng the proper p0: sitioning of the tray upon each operation of the same by the pawl and ratchet mechanism,

the shaft portion 45 is provided with a squared part 45. 53 designates a ring or yoke having a flat face 53? adapted to cooperate with the flat faces of the squared portion of the shaft, a weight 54 being connected with the ring or yoke 53 and acting to yieldingly maintain the flat surface of the ring or yoke flat against one of the flat faces of the squared portion of the shaft.

55, designates a handle part connected wlth the shaft portion 45 and arranged outside of the tank whereby the tray may be operated manually. On the handle portion 55 is an indicator projection 55, which lies at the upper part of the handle when the tray 13 m horizontal position.

The operation is as follows:

When the carbide feeding is in progress and while the gas is being generated, the tray or shelf, is stationary and remains stationary during the expansion of the diaphragm.

After the gas has passed out through the service pipe and the diaphragm starts to collapse or upon its inward movement the shelf or tray is turned to dump and reverse the same by the pawl and ratchet mechanism. the brake lever being actuated to release the motor upon the downward movement of the rod 36, after the tray or receptacle has been dumped and moved to reverse position to receive a fresh charge of carbide upon its reverse side.

It will be noted that the rotation of the screen or perforated tray through the bodyof water assists in completely freeing it of any sludge at each dumping operation. By generating the gas near the surface of the body of water the time taken for the gas to pass upward and out of the water is shortened,

thereby permitting the generator to be operated at lower pressures.

Also, at times, in the operation of acetylene gas generators in which carbide is fed into a body of water, the water supply becomes reduccd or scant and then the carbide is held in suspension near the top of the water. Under this condition, when the sludge or lime thickens the water, the carbide accumulates on the surface of the body of water, until it becomes too heavy a mass when it suddenly sinks and thereby generates a dangerous abnormal pressure. This condition is entirely obviated in applicants apparatus, the automatic shelf or screen, after each charge submcrges, serving to agitate and dump the residue of the charge.

In Figures 10 and 11' of the drawings, is illustrated a modified form of feed screw and operating mechanism. In these figures 56 is the tank and 57 the carbide chamber provided with a discharge part 57 leading to the feed tube 58. The feed screw, here shown, comprises a-shaft 59 provided with an integral spiral metal rib. and an outer yieldable spiral'blade part 60 adapted to tightly fit against the wall of the feed tube, said yieldable part 60 being of rubber andformed by molding or casting the same on the shaft. In this particular instance, the screw is mounted to reciprocate in the feed tube, the screw acting to free the carbide therefrom on the for- Ward movement thereof. The operating means for'the screw is shown as consisting of a diaphragm 61 connected with the screw by a rod 62, a spring 63 at the outer side of the diaphragm acting to exert pressure inwardly on the diaphragm, the tension of the spring 63 being such as to hold the diaphragm inwardly until the pressure of the gas in the tank reaches a predetermined degree. The rod 62 is provided with a universal joint 62. The joint 62' is arranged to cooperate with the rear end of the feed tube to serve as means for limiting the extent of inward movemei t of the rod 62, the construction being such that when the screw has been moved to its outward limit. the rear end of the feed screw lies ingvzardly of the opening of the discharge part What I claim is:

' 1. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforated shelf in the tank to receive the carbide from the feeding means, said shelf being adapted to be shifted to dump the spent charge therefrom, and mechanism governed by the gas pressure for operating the shelf.

2. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforated shelf in the tank to receive the carbide from the feeding means, said shelf being adapted to be shifted to dump the spent charge therefrom, and mechanism operatively connected with the carbide feeding means for operating the shelf prior tothe operation of said feeding means.

- 3. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforated arranged and movably mounted within the tank whereby the same is adapted to be moved to dump the spent ehar e from the compartments, and when one of the compartments is in dumping position, another of the compartments will be in receiving position, and

automatic means for shifting the receptacle d at intervals prior to the operation of the feeding means.

5. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforated shelf in the tank to receive the carbide from the feeding means, said shelf being supported for rotation and adapted to be turned to reverse the same to dump the spent charge from one side thereof and present its opposite side to receive carbide, and means acting automatically to shift the perforated shelf at intervals prior to the operation of the feeding means;

6. In a gas generator, a tank, means for supplying water to the tank, means for feedingcarbide to the tank controlled by the gas pressure, in combination with a perforated receptacle within the tank to receive carbide froin the feeding means, said receptacle being supported for rotation and comprising two per orated compartments arranged diametrically opposite each other, the receptacle being adapted to be turned to dump the spent charge from its compartments, and when one of the compartments of the receptacle is in dumping position the other is in receiving position, and automatic means for shifting the receptacle at intervals prior to the operation of the feeding means.

7. In agas generator, a tank, means for supplyingwater to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforated receptacle within the tank to receive carbide from the feeding mechanism, said receptacle being supported for rotation within the tank and comprising a single bottom part with side walls extending from opposite sides thereof providing oppositely 'disposed compartments, the receptacle being supported for rotation and being adapted to be turned to dump the spent charge from one of its compartments and present the other in carbide receiving position, and automatic means for shifting the receptacle at intervals prior to the o eration of the feeding means.

11 a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank, in combination with a perforated receptacle within the tank to receive carbide from the feeding means, said receptacle comprising a single bottom part and-side walls extending from opposite sides of the bottom providing oppositely disposed compartments, and journals extending from opposite ends of the bottom part engaging bearings on the tank and providing a rotatable support for the receptacle, and automatic means for turning the receptacle'at intervals.

mgcarbidc to the tank including a feeding cv ce, power means for driving said feeding device, and gas pressure controlling means for said power meansincluding a diaphragm subject to the gas pressure in the tank, a brake for said power means, and an operative connection between the diaphragm and brake, in combination with a erforated shelf in the tank to-receive the car ide from the feeding means, said shelf being supported for rotation and adapted to be turned to dump the spent charge, and an operative connection between the diaphragm and said shelf for rotating the shelf to dump the spent charge prior to the operation of the carbide feeding means. 10. In a gas generator, a tank, means for supplying water to the tank, means for feeddevice, ;power meansfor driving the feeding means and pressure controlled regulating means for said power means including a diaphragm subject to the gas pressure in the tank, a brake for said power means, a rod connected to the diaphragm and' with the brake, in combination with a perforated shelf within the tank to receive the carbide from the feeding means, said shelf being supported for rotation and adapted to be turned to dump the spent charge means, and a pawl and ratchet connection between said rod and shelf for turning the shelf to dump and reverse the same prior to the operation of the feeding means.

11. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforated shelf in the tank to receive the carbide from the feeding means, said shelf being supported for rotation .andadapted to be turned and reversed, and means for turning the shelf to reverse the same prior to the operation of the feeding means, said means including a diaphragm subject to the gas pressure in the tank, and a pawl and ratchet connection between the diaphragm and the shelf.

'12. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a horizontally disposed rotary shaft in the tank supported for rotation, a perforated shelf fixed on the shaft to receive carbide from the feeding means, said shelf being adapted to be turned and reversed by the rotation of said shaft, and operating means for the shelf including a diaphragm subject to the gas pressure in the tank, a rod connected with the diaphragm, and a pawl and ratchet connection between the rod and shaft.

13. In a gas generator, a carbide chamber, and feeding mechanism including a feed tube connected with said chamber, and a feed screw arranged to work in the tube, the main portion of the blade of the screw being formed of rigid material and provided with a recess at its periphery, and a strip of flexible material seated in the recess and pro'ecting beyond the rigid part of the blade to ear against the wall of the tube.

14. In a gas generator, a carbide chamber, a feeding mechanism including a feed tube connected with said chamber, and a feed screw arranged to work in the tube, the main portion of the blade of the screw being formed of rigid material and provided with a recess at one side thereof, a strip of flexible material seated in said recess and projecting beyond the rigid part of the blade to bear against the wall of the tube, an outer clamping strip, and screws securing the clamping strip to the rigid portion of the blade against one side of the flexible strip.

15. In a gas generator, a carbide cham-' her, and feeding mechanism including a feed tube connected with said chamber, and a feed screw arranged to work in the tube, the main portion of the blade of the screw being formed of rigid material and provided with a recess at its outer periphery extending around one side thereof, a strip of flexible material arranged in the recess with its outer portion projecting beyond the rigid portion of the blade to bear against the wall of the tube, a fastening strip, and screws for securing the fastening strip to the rigld portion of the blade against one side face of the flexible strip, said recess being of a width so that the outer side face of the fastening strip extends substantially flush with the adjoinlng side face of the blade.

16. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforate shelf in the tank to receive the carbide from the feeding means, said shelf being adapted to be shifted to dump the spent charge there from, an automatic mechanism for operating the shelf at intervals after the charge of carbide has given up its gas.

17 In a gas generator, a tank, means for supplying water to the tank, means for feedmg carbide to the tank controlled by the gas pressure, in combination with a perforated shelf in the tank to receive the carbide from the feeding means, said shelf being support ed for rotation and adapted to be turned to reverse the same to dump the spent charge from one side thereof and resent its 0 pcsite side to receive a freshc arge of car ide, and means acting automatically to shift the perforated shelf at intervals after the charge of carbide has given up its gas.

18. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, a horizontally disposed shaft supported for rotation in the tank, a perforated shelf fixed on the shaft to receive carbide from the feedmg means, said shelf being adapted to be turned and reversed by the rotation of said shaft, and operating means for the shelf including a diaphragm subject to the gas pressure in the tank, a rod connected with the diaphragm, a pawl and ratchet connec tion between the rod and shaft providing for rotation of the shaft upon movement of said rod in one direction, in combination with positionlng meansassociated with the shaft ineluding a part on said shaft having angu larly related faces, a member associated with the shaft portion and having a fiat face portion adapted to engage the angularly related faces thereof, and means yielolably holding said member with its flat face against one of the flat faces of the shaft.

19. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the. tank controlled by the gas pressure, a horizontally disposed shaft supported for rotation in the tank, a perforated shelf fixed on the shaft to receive carbide from the feeding means, said shelf being adapted to be turned and reversed by the rotation of said shaft, and operating means for the shelf including a diaphragm subject to the gas pressure in the tank, a rod connected with the diaphragm, a pawl and ratchet connection between the rod and shaft providing for rotation of the shaft upon movement of said rod in one direction, in combination with shaft positioning means including a squared part on said chamber, a yoke associated with said squared portion of the shaft and having an inner flat portion adapted to engage one of the fiat faces of the shaft portion, and a weight connected with the yoke and acting to yieldably maintain the yoke in position with its fiat face against one ofthe fiat faces of the shaft.

llEi

20. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank controlled by the gas pressure, in combination with a perforated shelf in the tank to receive the carbide from the feeding means, said shelf being supported for rotation and adapted to be turned to reverse the same to dump a spent charge from one Side thereof and to present its opposite side to receive a fresh charge of carbide, automatic means for operating the shelf at intervals, and manually operable means to operate the shelf independently of said automatic means.

21. In a gas generator, a tank means for supplying water to the tank, and means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet openin of the carbide chamber, the wall of the feed tube being imperforate, a feed screw arranged to work in said tube, said screw having a flexible outer peripheral portion to bear against the wall of the feed tube and form a moisture tight seal between the tank and the outlet opening of the carbide chamber.

22. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet opening of the carbide chamber, the wall of the feed tube being imperforate, a feed screw arranged to work in said feed tube, said feed screw having a yieldable outer peripheral portion to bear against the Wall of the feed tube and form a moisture tight seal between the tank and the outlet opening of the carbide chamber.

23. In a gas generator, a tank, means for supplying water to the tank, means for feed-, ing carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet opening of the carbide chamber, the wall "of the feed tube being imperforate, a feed screw arranged to work in said feed tube, said feed screw having an outer eripheral portion of rubber to bear against t e wall of the feed tube and form a moisture tight'seal between the tank and the outlet opening of the carbide chamber.

24. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet opening of the carbide chamber, the wall of the feed tube being imperforate, a feed screw arranged to work in said feed-tube said feed screw having a flexible outer peripheral portion to bear against the wall of the feed moisture ti ht seal between the tank and the outlet opening of the carbide chamber, said outer peripheral portion at its marginal edge having a beveled face.

25. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet opening of the carbide chamber, the wall of the feed tubebeing imperforatc, a feed screw arranged to work in said feed tube, said feed screw having a flexible outer peripheral portion to bear against the wall of the feed tube and form a moisture tight seal between the tank and the outlet opening of the carbide chamber, said outer peripheral portion at its marginal edge having beveled faces at opposite sides thereof.

26. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet opening of the carbide chamber, the wall of the feed tube bein imperforate, a feed screw arranged to wor in said feed tube, the main portion of the blade of the feed screw being formed of ri id material, and yieldable means at the peripheral portion of the blade of the feed screw to bear against the wall of the feed tube and form a moisture tight seal between the tank and the outlet opening of the carbide chamber.

In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet opening of the carbide chamber, the wall of the feed tube being imperforate, a feed screw arranged to work in said feed tube, the main portion of the blade of the feed screw being formed of rigid material, and a strip of flexible material secured to the outer peripheral portion of the rigid part of the screw and projecting beyond the same to bear against the wall of the feed tube and form a moisture tight seal betwen the tank and the outlet opening of the carbide chamber.

28. In a gas generator, a tank, means for supplying Water to the tank, means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet openingof the carbide chamber, the wall of the feed tube being imperforate, a feed screw arranged to work in said feed tube, the main ortion of the blade of the feed screw being ormed of rigid material, and a strip of yield able material secured to the outer eripheral portion of the rigid part of the eed screw and projecting beyond the same against the wall moisture tight seal between the tank and the outlet opening of the carbide chamber.

29. In a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank including a carbide chamber above the tank having an outlet opening, a feed tube connected with the outlet opening of the carbide chamber, the Wall of the feed tube being imperforate, a feed screw arranged to Work in said feed tube, the main portion of the blade of the feed screw being formed of rigid material, and a strip of rubber secured to the outer portion of the main rigid part of the feed screw and projecting beyond the same to bear against the wall of the feed tube and form a moisture tight seal between the tank End the outlet opening of the carbide cham- 30. lln a gas generator, a tank, means for supplying water to the tank, means for feeding carbide to the tank including a carbide chamber having sloping bottom walls, an outlet opening, a delivery spout leading from said outlet opening, a feed tube disposed at the lower end of and communicating with the delivery spout, and a feed screw in the feed tube, said delivery spout comprising oppositely inclined sections adjoining and disposed one above the other directly adjoining the feed tube, said delivery spout sections being of relatively small cross sectional size, and operating means for said feed screw.

In testimony whereof I hereunto afiix my signature.

CHARLES W. BECK.

Images