US865424A

US865424A - Air-compressor.

Info

Publication number: US865424A
Application number: US30860906A
Authority: US
Inventors: George Campbell Mcfarlane
Original assignee: Individual
Current assignee: Individual
Priority date: 1906-03-28
Filing date: 1906-03-28
Publication date: 1907-09-10
Anticipated expiration: 1924-09-10

Description

No. 865,424. PATENTED SEPT. 10, 1907..

G. G. MOFARLANB.

AIRGOMPRESSOR.

APPLICATION rum) m3. 2a. 1906.-

2 sEnETs-snnET 1 INVENTOR 5? BY ATTORNEY THE Monms PETERS co wnsnmcnm, n. c.

No. 865,424. PATENTED SEPT. 10, 1907.

G. C. MGFARLANE- I AIR COMPRESSOR.

APPLICATION FILED MAR. 2a, 1906.

2 sums-sum 2.

WITNESSES:

ATTORNEY 1n: NDRRIE PETERS co-, WASHING70N. n. c.

GEORGE CAMPBELL MCFARLANE, OF BAY CITY, MICHIGAN.

AIR-COMPRESSOR.

Specification of Letters Patent.

Patented Sept. 10, 1907.

Application filed March 28. 1906. Serial No. 308,609.

To all whom it may concern:

Be it known that I, GEORGE CAMPBELL lVICFARLANE, a citizen of the United States, residing at Bay City, in the county of Bay and State of Michigan, (post-office address, Lancaster, California) have invented certain new and useful Improvements in Air-Compressors; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to hydraulic air compressors, one object of which is to provide a simple and efficient means for supplying a liquid under a head or under pressure to a chamber containing-air for the purpose of compressing the air in the chamber.

The invention further contemplates the provision of means for alternately supplying the chamber with liquid and emptying it of liquid in combination with means for supplying the chamber with successive charges of air.

Another object of the invention is the provision of means for automatically effecting the entrance of liquid to the chamber and its evacuation therefrom.

A still further object is the provision of means for utilizing so called dead or idle liquid to assist in filling the chamber, thus materially economizing the liquid under pressure.

Other objects reside in the provision of means for controlling the supply of liquid, under pressure, the evacuation of liquid from the chamber and the exclusion of the liquid from the compressed air reservoir conduit. My invention further consists in certain other novel features and combinations of parts together with their equivalents, such as will be more fully described hereinafter and particularly set forth in the claims.

The invention is capable of use wherever liquid under pressure may be obtained and by combining the machines, a low pressure liquid may be employed to produce a highly compressed air.

My invention is adapted for use in mountain districts for instance, or at other places where a head of water is obtained from a source located above the mechanism or from a pump.

- In the accompanying drawings, wherein one embodiment of my invention is illustrated, Figure 1 is a vertical sectional view of the device, and Fig. 2 is an enlarged detail view of one means for operating the controlling mechanism.

It should be understood that in the drawings and'in the following description I have illustrated and set forth a preferred form of mechanism embodying my invention, but it by no means indicates that the present application contains the only form which my invention is capable of assuming.

The present embodiment of my invention consists liquid supply conduit (2) leading briefly of a chamber (A) which may be of the tankform shown, from which leads the compressed air pipe (1) communicating with a compressed air reservoir of any suitable design, (not shown), combined with a from any suitable source and furnishing liquid under pressure or head to the chamber together with means for controlling the entrance of liquid to the chamber and its evacuation from the chamber, and means for supplying the chamher with air, the object being to fill or partially fill the chamber with liquid to compress the air in the chamber and force it through the pipe (1) after which the supply of liquid is cut off and the liquid within the chamber permitted to escape therefrom to permit the entrance of a further supply of air thereto. The liquid is then resupplied to the chamber to compress the new supply of air and so on.

In the drawings therefore, A indicates the chamber or tank for receiving the liquid and air and in which the air is compressed. This chamber at its upper end is provided with a compressed air pipe (1) leading to a compressed air reservoir, the pipe being provided with a check valve (3) of any approved type to prevent back pressure and retain the air in the reservoir until used. The mouth or inlet (4) of the pipe may conveniently be provided with a suitable buoyant valve (5) adapted to close the seat (6) in the pipe in the event that the liquid in the chamber rises too high, the object being to prevent the entrance of the liquid into the pipe (1). Normally however this valve remains off its seat at all times. Located preferably at the upper end of the chamber is an air inlet valve (7)of any approved type adapted to admit air into the chamber, and to prevent its exit therethrough.

The chamber (A) is preferably situated above the reservoir (8) from the upper portion of which leads a fiume (9), the area of the reservoir being advantageously proportioned relative to the area of the chamber, so that the reservoir contains at least as much liquid as is required to fill the chamber, and the bottom of the chamher is closed save for an aperture (10) surrounded by a stuffing box (11) of suitable design, the aperture and stuffing box adapted to receive an injector which is slidingly located therein. The injector may be constructed in a variety of ways and forms, that shown, however, being a preferred form and comprising a preferably cylindrical sleeve (12) engaging and filling the aperture and stui'ling box, the sleeve having secured thereto a tube (13) flared at both ends and constricted intermediate thereof, the upper end of the tube conveniently terminating at or merging into the upper end of the sleeve, the lower end of the tube projecting preferably some distance beyond the lower end of the sleeve, which may be advantageously closed upon the tube as shown to prevent the entrance of liquid be tween the tube and sleeve. When the injector is at one limit of its movement the tube and sleeve project conveniently some distance into the chamber (A) so that the level of liquid within the chamber can never descend under normal conditions, below the upper end of the tube. This however is not essential, it being necessary merely to provide a sleeve of such length that it will remain in its bearing or stuffing box at all times during the operation of the device. The lower end of the tube (13) depends into the reservoir and is always below the level of the flume (9), that is to say, it is submerged in the liquid in the reservoir as will be set forth in detail hereinafter.

A suitable liquid supply, as water, is led through a conduit (2) to a preferably tapered nozzle (14), which may conveniently project upward through the bottom of the reservoir in alinement with and preferably surrounded by the lower flaring end of the tube (13), and terminating beneath the level of liquid in the reservoir.

It is obvious that it is possible to connect the supply pipe (2) directly in communication with the chamber (A) but by so doing the entire force or energy of the liquid would be utilized to fill the .entire chamber, thereby wasting considerable energy at the start, since the full force of the liquid is not needed at the outset to par tially fill the chamber. In other words, the air in the chamber may be compressed to say double and triple atmospheric pressure by a low head or pressure and hence to permit the entrance of the full head of water.

at say one-hundred pounds pressure to compress air from atmospheric pressure to say eighty or ninety pounds is not desirable, particularly in those localities where water is scarce and is used for other mechanisms as well. I, therefore, place a plug (15) within the nozzle,,the plug preferably tapered in conformity with the bore of the nozzle, the base of the plug adapted to fit the discharge end of the nozzle to close the latter.

It is, of course, necessary to provide means for operating the sliding injector and the plug, and while a number of devices or arrangements might be constructed, I have shown one form of mechanism for accomplishing these objects which has given satisfaction, the same consisting of separate motors, to the pistons of which the injector and the plug are respectively connected. The cylinders may be arranged in any desired manner relative to each other and the power necessary to operate the motors may be derived from any suitable source and controlled relative to the motors, by hand or automatically. In the present instance, however, I

.have shown a pair of cylinders (16) and (17) preferably located on top of the chamber (A) and arranged in tandem, the cylinders being conveniently placed in alinement with the injector and plug. Within the cylinders are located the traveling pistons (18) and (19), the piston (18) being connected to the injector by means of the rigid rods (20) (20), the piston (19) being connected to the plug by means of a rod (21). Suitable combined inlet and outlet pipes (22) and (23) are provided for each cylinder and adapted to communicate with the opposite ends of the respective cylinders for admitting and exhausting pressure to cause the reciprocation of the pistons. Located at some convenient point in each of the combined inlet and outlet pipes, are the valves (24) and (25), one for each pipe, the valves being preferably of the rotary typeand each having a supply pipe (26) and an exhaust pipe (27) communicating therewith. Interiorly, each valve is provided with two separate ports (28) and (29) one of which (28) is adapted to connect one end or the other of the combined inlet and outlet pipe with the supply pipe (26), and the other port (29) is adapted to connect one end or the other of the combined inlet and outlet pipe with the exhaust pipe (27). Inasmuch as both valves are alike, the showing of one valve in section is thought to be sufficient.

The supply pipes (26) are preferably connected to the liquid conduit (2), but it is obvious that they may receive steam or other motive power from a different source.

Secured to the stem of valve (24) is a bell crank (30) to one arm of which is pivotally secured one end of the valve rod (31) said rod passing down into the chamber (A) and terminating preferably a little short of the bottom, the aperture through which the rod passes into the chamber (A) being suitably packed to prevent leakage of air. Located on the rod at suitable distances apart are a pair of adjustable tappets (32) (32) and a float (33) is slidingly mounted on the rod between the tappets, the movement of the float relative to the rod being limited by the tappets with which it comes in'contact, the float being of suflicient weight to move the rod downward, and of suflicient buoyancy to move it upwardly, depending upon the tappet engaged by the float. The opposite end of the bell crank (30) has one end of a slotted bar (34 (pivotally attached thereto, the slot (35) located near the opposite end of the bar, the free end of an arm (36) operating valve (25), being connected with the slot in the bar. It will thus be seen that when the float rests upon the lower tappet, both valves will be operated to permit the entrance of motive power into the cylinders to simultaneously cause a downward movement of the injector and the plug or cut off. When the float strikes the upper tappet, however, it will only cause the valve rod to operate valve (24), the slotted bar (34) moving relative to the arm (36) of valve (25), and no movement will be imparted thereto. As one means for reversing valve (25), therefore, I may mount a standard (37) on the upper cylinder, (16) to which standard is pivotally secured a rocking lever (38). Depending from one end of the rocking lever is a kicker rod (39) which passes into the cylinder (16) and is adapted to be engaged by the piston therein to effect a rocking of the lever in one direction. The opposite end of the rocking lever has secured thereto one end of a thrust rod (40), the opposite end of which is pivotally connected to the free end of the arm (36). Hence as the piston in cylinder (16) nears the upward limit of its stroke, it engages the kicker rod and forces the latter upward, thereby moving the thrust rod downward in the slot to reverse valve (25).

Having thus fully set forth the construction of one embodiment of my invention, I will briefly describe its operation.

The reservoir (8) is filled with liquid any overplus being discharged into the flume (9), the level of liquid in the reservoir when the compressor is not in operation being even with the bottom of the flume, Liquid, as water under pressure, is led to the nozzle (14) through conduit (2), but when the parts are in the ward.

position shown in Fig. 1, the nozzle is closed by the plug, valve or cutofl' so that no water is permitted to enter the injector. Fig. 1 shows the arrangement of the parts just as the chamber is nearly empty, pistons (1S) and (19) being at the upward limit of their strokes, thereby drawing the plug (15) and the injector to their upward limits of movement, the upper ends of the cylinder being connected through the respective combined inlet and outlet pipes and the port (29) with the exhaust pipes (27) the lower ends of the cylinders being connected through the combined inlet and outlet pipes and the port (28) with the supply pipes (26). It will also be noted that the float (33) is resting upon the lower tappet, but has not moved it as yet, and the arm (36) of valve lies at the lower end of the slot (35) to which position it has been moved by the thrust rod 10), as the piston (19) approached its upward limit of movement. The water in the chamber has drained through the flared tube (13) into the reservoir and after filling the latter, has run out through the flume (9), the escaping water tending to create a vacuum in the chamber (A) which is replenished with air through the inlet valve (7). Assuming, therefore, that the lowest level of water has been reached in chamber (A), the weight of float (33) on tappet (32) will draw the sliding valve rod (3].) downward, until the lower end of the rod abuts the bottom of the chamber thereby preferably simultaneously rocking both the valve (24) and the valve (25) com pletely, to partially open the ports 28 to connect the supply pipes (26) with the upper ends 01' the cylinders (16) and (17) to force the pistons (19) and (18) down- It is, of course, possible to operate the valves (24) and (25) by hand, or to connect them in such a manner that they will not operate simultaneously, but I prefer the construction herein described. The object of not rocking the

valves

24 and 25 to cause them to completely register with their ports is to prevent a full opening of the ports connecting the supply with the upper ends of the cylinders whereby to cause ,.a comparatively slow operation 01 the piston (19) to slowly lower the plug against the pressure oi the water behind it and permit a gradually increasing head of water to issue from the nozzle, and a comparatively slow operation of piston (18) to slowly lower injector (l3) and gradually reduce the quantity of dead water mixing with the water under pressure so that the pressure of the liquid entering the chamber always slightly exceeds the back pressure caused by the continually increasing compression of the air in the chamber. The pressure of liquid issuing from the nozzle is constant, but the pressure of the liquid entering the compression chamber is reduced by the accompanying idle water. Hence in reducing the amount of idle water admitted to the flared tube (13), the pressure of the liquid entering the compression chamber is increased. Of course this mode of operation is not essential to the invention.

When the ports (28) have been brought into communication with the supply pipes (26) and the upper ends of the cylinder, the ports (29) are brought into communication with the lower ends of the cylinders, and the respective exhaust pipes (27) so that as the motive power enters the cylinder above the piston, the contents of the cylinder below the piston escapes. As the plug or cutoff descends in the nozzle, a small stream of water under high pressure issues from the nozzle into the lower end of the injector and passes therethrough into the chamber drawing with it a much larger quantity of the idle water which is contained in the reservoir. In this manner the column of water under high pressure is economized, as a small volume of water un der a comparatively low pressure only is necessary to partially fill up the tank or chamber (A). As the chamber fills with water, the air within the chamber becomes compressed, more and more, and this would tend to prevent the entrance of the small stream of water from the nozzle, but simultaneously with the increase in pressure in the chamber, the head of the stream of water entering the chamber is increased owing to the downward movement of the plug and injector, thereby causing an increase in the volume of high pressure water and a decrease in the amount of idle water mixing with it, until at last the stream of water from the nozzle is flowing at the full capacity of the nozzle, whereby to nearly or completely fill the chamber tov compress the air therein as fully as possible. It may be convenient to cause the constricted portion of the tube to snugly fit around the upper end of the nozzle when the injector is at its lowest limit of movement to prevent the mixture of any idle water with the stream from the nozzle. When the pressure of air in the chamber overcomes that in the compressed air receiver (not shown), it will escape thereinto past the check valve (3) of the air pipe (1.). As the tank (A) fills with water, the float (33) is raised until it is brought against the upper tappet (32) whereupon a further entrance of water to the tank will cause the float to press against the tappet, thereby raising the valve rod (31) to reverse valve (24) to fully open the port 28 to connect the supply with the lower end of the cylinder (16), whereby motive power is admitted beneath the piston (19) now at its lowest position to rapidly force the piston to its upward limit of movement to draw the plug (15) into the mouth of the nozzle (14) to close the latter. The bar (34) is also moved owing to its connection with the bell crank but by reason of the slot (35) no movement is transmitted to valve (25). As the piston (19) approaches its upward limit of movement, it engages the lower end of the kicker rod (39) thereby rocking the lever (38) and through the thrust rod (40) moving the arm (36) to reverse valve (25), the reverse movement preferably i'ully opening port 28 to connect the supply with the lower end of the cylinder 17, whereby the injector is quickly raised to the position shown in Fig. 1, thereby permitting the water in the chamber (A) to drain through tube (13) into the reservoir filling the latter, any overflowescaping by way of the flume (9).

The partial opening only oi the ports 28 is accomplished by reason of the fact that the lower end of the valve rod (31) contacts with the bottom of the chamber when forced down by the weight of the float (33) resting on the lower tappet (32), thus preventing the full opening of the ports, or in. other words, limiting the arc of rotation of the valves, but the float is permitted to push the rod (31) up until the port is fully open to admit the full force of the motive power to the lower end of cylinder 16, whereby to quickly raise the plug and close the nozzle (14). Then the kicker rod (39) is so proportioned that the upward movement of the piston (19) will cause the actuation of valve (25) to fully open the port 28, to connect the supply with the lower end of the cylinder 17, to quickly raise the injector.

The object of first closing the nozzle is to shut off the flow of water into the chamber, as such flow would kick back into the reservoir as soon as the injector started on the up stroke. The injector is preferably, though not necessarily, raised more rapidly than it is lowered in order that it may attain its position for the next operation. The water in the chamber now drains out through the injector and as the level of water in the chamber decreases, the float (33) falls therewith until it engages the lower tappet (32) whereupon the loregoing operation is repeated.

The reservoir (8) constitutes a receptacle for an inert body of liquid which is drawn into the compressor chamber (A) by reason of the discharge of afluid (either liquid or gaseous) under pressure in such a maimer relative to the conduit member (13) as to cause a vacuum therein, the conduit member communicating with the reservoir and with the compressor or liquid-receiving chamber (A) respectively. A distinction is thus made between former arrangements for forcing all of the water into the chamber lor compressing the air therein, thereby wasting considerable power, and forcing a compara tively small amount of fluid into the chamber in such a manner as to cause it to draw with it an inert body of liquid.

It is obvious that many changes might be made in the form and arrangement of the several parts described without departing from the spirit and scope of my invention, and hence I do not wish to limit myself to the exact construction herein set forth.

Having thus fully disclosed my invention what I claim as new is- 1. A hydraulic air compressor comprising a stationary chamber, means for admitting air thereto, means for conveying compressed air therefrom, a single means for admitting liquid under pressure into the chamber and for subsequently permitting the evacuation of the liquid therefrom by gravity, and means for increasing the pressure of the liquid entering the chamber as the chamber is filling.

2. A hydraulic air compressor comprising a chamber, means for admitting air thereto, means for conveying compressed air therefrom, a single means for admitting a liquid under pressure to the chamber and for subsequently permitting the discharge of the liquid therefrom by gravity, means for controlling the liquid under pressure, a motor connected with said last named means, and means actuated by the level of liquid within the chamber for causing the actuation of the motor.

An air compressor comprising a chamber into which air and liquid are alternately admitted, means for conveying the compressed air from the chamber, means controlling the admission of live liquid to the chamber, and a movable hollow member, the movement of which is controlled by the level of liquid in. the chamber, for draining the chamber of liquid.

4. An air compressor comprising a chamber into which air and liquid are alternately admitted, means for conveying the compressed air from the chamber, means controlling the admission of live liquid to the chamber, and a sliding hollow member, the movement of which is controlled by the level of liquid within the chamber, the member alternately admitting liquid to the chamber and draining the liquid from the chamber by gravity.

An air compressor comprising a chamber, into which air'and liquid are alternately admitted, means for con veying the compressed air from the chamber, means con trolling the admission of live liquid to the chamber, a movable hollow member, a motor connected therewith, and means controlled by the level of liquid within the chamber for causing the actuation of the motor to raise or lower the member.

6. An air compressor comprising a chamber, means for admitting air thereto and for conveying compressed air therefrom, a conduit for conveying liquid under pressure to the chamber, a liquid-filled reservoir in which the discharge end of the conduit is submerged, a sliding hollow member in communication with the chamber and with the discharge end of the conduit, the lower end of the member being submerged beneath the level of the liquid in the reservoir and being of larger diameter than the discharge end of the conduit and means for raising and lowering the member.

T. An air compressor comprising a chamber, means for admitting air thereto and for leading compressed air therefrom, a single means for admitting liquid under pressure to the chamber, and for permitting its discharge therefrom by gravity, a conduit for discharging liquid under pressure through said last named means into the chamber, a plug for said conduit, a lnotor connected With the plug and means controlled by the level of the liquid within the chamber for causing a gradual opening and a swift closing of the conduit.

8. An air COllll'Jl'OSSOl. comprising a chamber, means for supplying air thereto, a conduit for supplying liquid thereto under pressure, a plug for regulating the stream of liquid issuing from the conduit, a motor to which the plug is connected, a valve for controlling the actuation of the motor, a valve rod received in the chamber and adapted to operate the valve, and a float controlled by the level of the liquid in the chamber and adapted to actuate the rod.

5). An air compressor comprising a chamber, means for supplying air thereto, a conduit for supplying liquid to the chamber, a plug for controlling the issuance of liquid from the conduit, a cylinder, a piston therein, means connecting the plug and piston, means for conducting power to one side or the other of the piston, a valve controlling the direction of application of the power, a valve rod connccted to the valve, and depending into the chamber, adjustable tappets on the rod and a float adapted to alternately engage the tappets to oscillate the valve and move the plug to open or closed position relative to the conduit.

10. An air compressor comprising a chamber, means for furnishing air thereto, a conduit for supplying liquid under pressure to the chamber, an injector communicating with the chamber, and surrounding the open end of the conduit, a reservoir into which the injector depends, and a cutoit for controlling the issuance of liquid from the conduit.

11. An air compressor comprising a chamber, means for supplying air thereto, a liquid holding reservoir beneath the chamber, an injector communicating with the chamber and depending into the reservoir and means for causing a supply of water from the reservoir to enter the chamber through the injector.

12. An air compressor comprising a chamber, a liquid holding reservoir, an injector communicating with the res ervoir and depending beneath the level of liquid in the reservoir, and means for discharging a liquid under pressure into the injector.

13. An air compressor comprising a chamber, a liquid holding reservoir adjacent thereto, a movable injector communicating with the chamber, and depending beneath the level of the liquid in the reservoir, a nozzle received within the lower end of the injector and adapted to discharge a stream of liquid under pressure thereinto, and means for controlling the stream of liquid discharged from the nozzle.

14-. An air compressor comprising a chamber, a liquid holding reservoir, an injector communicating with. the chamber. and depending beneath the level of the liquid in the reservoir, means for causing the passage of the, liquid in the reservoir through the' injector into the chamber, and means for moving the injector to retain its depending position bencatlrthe level of the liquid in the reservoir as such lcvcl decreases.

15. An air compressor comprising a chamber, means for supplying air thereto, a liquid holding reservoir, an injector. one end of which remains in communication with the chamber, the opposite'cnd of the injector depending below the level of liquid in the reservoir, a nozzle for discharging liquid under pressure into the lower end of the injector and means for gradually lowering the end of the in jector with the decreasing level of liquid in the reservoir. the injector at one limit of its movement adapted to cut oil communication between the reservoir and the interior of the chamber.

10. An air compressor comprising a chamber, means for supplying air thereto, a liquid holding reservoir. an injector, one end of which remains in communication with the chamber, the opposite end of the injector depending below the level of liquid in the reservoir. a nozzle for discharging liquid under pressure into the lower end of the iniector. means [or gradually lowering the lower end of the injector with the decreasing level of liquid in the res ervoir. and means for gradually increasing the stream of liquid issuing from the nozzle.

17. An air compressor comprising an air chamber, having an aperture at its lower end. an injector slidingly received in the aperture, a reservoir beneath the chamber, the lower end of the injector depending into the reservoir below the level of the liquid therein, means for drawing the liquid through the injector from the reservoir into the chamber to partially till the chamber and decrease the level of liquid in the reservoir, andmeans for moving the injector downward to retain its lower end beneath the level of liquid in the reservoir as the latter decreases,

18 An air compressor comprising an air chamber, havin an aperture at its lower end, an injector slidingly received in the aperture. a reservoir beneath the chamber, the lower end of the injector depending into the reservoir below the level of the liquid therein. means for drawing the liquid through the injector from the reservoir into the chamber to partially fill the chamber and decrease the level of liquid in the reservoir and means for moving the injector downward to retain its lower end beneath the level of liquid in the reservoir as the latter decreases.

1!). An air compressor comprising an air chamber, having an aperture at its lower end. an injector slidingly received in the aperture. a reservoir beneath the chamber, the lower end of the injector depending into the reservoir below the level of the liquid therein, means for drawing the liquid through the injector from the reservoir into the chamber to partially till the chamber and decrease the le\el of liquid in the reservoir and means for moving the injector downward to retain its lower end beneath the level of liquid in the reservoir as the latter decreases, and for raising the injector to permit the liquid within the chamber to drain therethrough back to the reservoir to fill the latter. I

it). An air compressor comprising a chamber, means for supplying air thereto. a reservoir. a movable injector co1nmunicating with the chamber. the lower end of the in jeetor depending below the level of liquid in the reservoir, a nozzle for supplying liquid under pressure to the injector and chamber. whereby to draw a large portion of liquid from the reservoir into the chamber, means for moving' the injector to retain its lower end beneath the constantly decr 'ising' level of liquid in the reservoir and means for simultaneously causing an incre sing volume of liquid to issue from the nozzle.

21. The combination. in an air compressor, of a liquidholding reservoir, a chamber. a means for supplying liquid under pressure to the chamber and means into which the liquid under pressure is discharged for causing said liquid under pressure to draw therewith the liquid in the reservoir.

12:. An air compressor comprising a liquid-receiving chamber, a reservoir containing a body of liquid. a conduit member communicating with the reservoir and with the chamber respectively to form a combined inlet and outlet for the chamber, the liquid in the reservoirhaving free access to the conduit member, and means for discharging lluid under pressure to the conduit member so as to cause the liquid in the reservoir to be drawn into the chamber with the tluid under pressure.

22;. An air compressor comprising a compression chamber. having a combined inlet and outlet opening for liquid, a reservoir open to the atmosphere and constituting a receptacle for a body of idle. liquid, means discharging a jet of fluid under pressure into the combined inlet and outlet opening of the compression chamber, means for intermittently cutting off the jet of fluid to allow the liquid in the compression chamber to drain back through the combined inlet and outlet: opening into the reservoir, the liquid in the reservoir having access to the fluid jet. whereby it is carried therewith into the compression chamber, and means actuated by the escape of the liquid from the chamber to admit air to the chamber.

24. An air compressor comprising a chamber, a reservoir, an injector communicating with the chamber, the iirector comprising a sleeve, and a tube flared at both ends. the lower end of the tube depending beneath the level of the liquid in the reservoir and means discharging into the injector for causing the liquid in the reser voir to travel through the injector into the chamber.

2 An air compressor comprising a compressing chamber, a reservoir, a sliding injector communicating with the chamber, the lower end of the injector depending beneath the level of liquid in the reservoir, a discharge pipe emptying into the lower end of the injector, a cutoff controlling the amount of liquid discharged into the injector, and means for simultaneously moving the injector to retain its lower end beneath the level of the liquid in the reservoir and for gradually increasing the discharge from the pipe.

26. An air compressor comprisinga compression chamber, a liquid holding reservoir, a combined inlet and outlet member for the chamber, the liquid in the reservoir having free access to the member, and means for intermittently supplying fluid under pressure to the compression chamber through the member to induce a flow of idle liquid from the reservoir into the chambeuwith said fluid under pressure.

27. An air compressor comprising a compressing chamber, means for supplying a stream of liquid under pres sure thereto, means for inducing the flow of idle liquid with said stream, and means for increasing the stream as the supply of idle liquid diminishes.

28 An air compressor comprising a compressing chamber, means for supplying a stream of liquid under pressure thereto, means for inducing the flow of idle liquid with said strenn, and means for increasing the stream of liquid under pressure and decreasing thc amount of accompanying idle liquid as the pressure within the chamber increases.

29. An air compressor comprising a compression chamber, a reservoir for idle liquid, an injector communicating with the chamber, the lower end of the injector depending beneath the level of liquid in the reservoir, a supply pipe adapted to discharge a stream of fluid under pressure into the lower end of the injector, a cutoit for regulating the size of the stream of fluid, means for simultaneously and nonsynchronously moving the injector to maintain its lower end beneath the decreasing level of idle liquid and for gradually increasing the volume of the stream of liquid discharged into the injector, as well as to cut off the stream 01 water and raise the injector.

30. An air compressor comprising a compressing chamber, a reservoir, an injector communicating with the chamber, the lower end of the injector subme. ed beneath the level of liquid in the reservoir and a nozzle projecting into the lower end of the injector and adapted to discharge a stream of liquid under pressure therein'to.

31. An air compressor comprising a compressing chamber, a reservoir, an injector communicating with the chamber, the lower end of the injector submerged beneath the level of liquid in the reservoir and a nozzle projecting into the lower end of the injector and adapted to discharge a stream of liquid under pressure thereinto, a cutoff for regulating the stream of liquid from the nozzle, a pair of motors. means connecting the cutoff and the -injector to the respective motors, valves for admitting motive power to the motors, means connecting the valves, means affected by the height of water in the compressing chamber for actuating the valves simultaneously to cause a movement of the injector and cutoit', and for operating a single valve to cause the actuation of the cutoli. to stop the flow of liquid from the nozzle, and means actuated by the cutoff motor to operate the valve of the injector motor to raise the injector.

32. An air compressor comprising a compression cham her, a reservoir, an injector communicating with the chamber, the lower end of the injector depending beneath the liquid level in the reservoir, a nozzle discharging into the injector, a cutoff controlling the volume of discharge, motors to which the cutoff and injector are respectively connected, valves for admitting power to one side or the other of the motors, a slotted bar connected to one of the valves, a kicker rod adapted to be engaged by the cutoff motor as it approaches one limit of movement, a lever to which the kicker rod is connected, a thrust rod operated by the lever and connected to the injector motor valve, through the slot in the bar and means actuated by the height of liquid in the compressing chamber for operating both valves simultaneously to admit liquid to the chamber or to operate the valve for the cutoff motor to stop the discharge from the nozzle.

33. An air compressor comprising a compressing cham ber, a reservoir, an injector communicating with the cham her, the lower end of the injector depending beneath the liquid level in the reservoir, a nozzle discharging into the injector, a cutoff controlling the discharge, and automatic aneans for simultaneously and non-synchronously operating the cutoif and injector to admit liquid to the chamber and for successively operating the cutott and injector to stop thedischarge from the nozzle and permit the liquid in the chamber to escape.

34. An air compressor comprising an air chamber, a movable hollow member for admitting liquid under pressure thereto, means for supplying liquid under pressure to the hollow member, and a liquid holding reservoir with which the member communicates, the hollow member permitting the liquid in the chamber to drain out by gravity into the reservoir subsequent to the compression of a charge.

An air compressor comprising a chamber, means for admitting air thereto and for conveying compressed air therefrom, a conduit for conveying liquid under pressure to the chamber, a liquid-filled reservoir in which the dis-' charge end of the conduit is submerged, a sliding hollow member in communication with the chamber and with the discharge end of the conduit respectively, the lower end' of the member being submerged beneath the level of the liquid in the reservoir and being of larger diameter than the discharge end of the conduit, a plug for controlling the emission of liquid from the conduit, and means set in motion by the level of the liquid in the chamber for gradually lowering the member around the discharge end of the conduit to restrict the amount of idle liquid drawn thereinto and for actuating the plug to gradually increase the amount of live liquid discharged from the conduit as the chamber is filling and to swiftly close the discharge end of the conduit when the chamber is filled.

36. An air compressor comprising a compressing cham ber, a liquid-holding reservoir, a movable injector communicating with the chamber and with the liquid in the reservoir. a conduit discharging liquid under pressure into the injector, a cutoff controlling said discharge and automatic means for operating the cut-off to cause a gradually increasing discharge from the conduit, and for successively actuating the cut-off and injector to swiftly stop the discharge from the conduit and permit the liquid in the chamber to escape into the reservoir to replenish the latter.

37. An air compressor comprising a chamber, a liquid holding reservoir, means for conveying a liquid under pressure into the chamber and for drawing the liquid in the reservoir into the chamber and for permitting the liquid in the chamber to replenish the reservoir.

38. An air compressor comprising a compressiortchamher, a liquidholding reservoir constituting a receptacle for an inert body of liquid and a single means operating as a combined inlet and outlet for the chamber, adapted to receive intermittently a fluid under pressure for drawing the inert liquid from the reservoir directly into the chamber, the inert liquid having free access to the combined inlet and outlet means.

In testimony whereof, I ai'lix my signature in presence of two witnesses.

GEORGE CAMPBELL MCFARLANE.

Witnesses W. A. BALLOT], C. S. Ro'r'rraa.