US1704238A - Air engine - Google Patents

Description

4 Sheets-Sheet 1 F- S. BARKS March 5, 1929,

AIR ENGINE Original Fled Dec. 3, 1925 Kxxm. K n @www @www F. S. BARKS AIR ENGINE March 5," 1929.

Original Filed Dec. 3, 1925 4 Sheets-Sheet March 5, 1929-. F 5 BARKS 1,704,238

AIR ENGINE original Filed Dec. 1925 4 sheets-sheet 5 F. 5. BARKS AIR ENGINE March 5, 1929.

Original Filed Dec. 5, 1925 4 Sheets-Sheet Litl Patented Mar. 5, 1929.

. UNITED STATES 1,704,238 PATENT oFFlcE- FRANK S. .'BARKS, 0F ST. LOUIB,MISS0URI.

In ENGINE l Original application led December 3, w/Serial No. 72,898. Divided and this application led June 28, 1926. Serial No. 119,118.

This invention relates to air engines or motors, and with regard to certain more speciiic features to an air engine for operating a portable grease pump or the like.

This application is a division of the invention set forth in my patent application on a lubricating device, Serial No. 72,898, led December 3, 1925.

Among the several objects of the invention may be noted the provision of a portable grease pumping engine which is instantly operable to pump quantities of grease merely upon manual operation of a valve; the provision of a pneumatic grease pumping engine which is adapted to receive air tor operation from the ordinary pneumatic tire iilling air line and valve; the/` lrevision ot apparatus of the class described which pumps predetermined quantities of *l grease; the provision of apparatus of the class described comprising in part an improved hill-stroke valve gear and cooperating seli3 y oi': a device of the clamss described which is economical of manufacture, light in weight, yet subject to little or no derangement in operation. *Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly consists oit' the i eiements and combination of elements, features oi construction, and arrangements of parts which will be exemplified in the structure hereinafter described and the scope of` the application of which will be indicated in the following claims.

In the accompanying drawings, n which is shown one of various possible embodiments of the invention,

Fig. 1 is a top plan view of the apparatus,

showing parts broken away;

Fig. 2 is a longitudinal vertical section taken on line 2 2 of Fig. 1;

Fig. 3 is a rear elevation of, the device showing certain parts broken away;

Fig. 4 is a vertical lateral section taken on line 4-4 of Fig. 2; and

Fig. 5 is a diagrammatic plan view showing in solid lines the arrangement of vari ous parts while yin use, and in dotted lines shows the arrangement of .certain parts when the device is not in use.

Similar reference characters indicate cor-y responding parts throughout` the several views of the drawings.

aligning device; and the provision Referring now more particularly to Figs. l and 2 of the drawings, there is illustrated at numerals 1 and 3, a pair of longitudinal with a swivel caster 7.' The casters 7 are adapted to stay with the legs 5, when the device is picked up as will be hereinafter described.

The rails 1 and 3 are provided with upper horizontal flat machined surfaces 9 for the purpose of receiving bolted thereto, at the forward ends, a laterally formed pump casting 11. Rearwardly the surfaces 9 of the frames 1 and 3 have bolted thereto a laterally formed engine casting 13. The frames 1 and 3 and castings 11 and 13 form a unit. For stiffening purposes a cross-bolt 14 and spacer 16 .(Figs. 1 to 3) are provided laterally between andv centrally of the side frames. This ,stidening device may be dis- -pensed with in small sizesot the pump.

Between the castings 13 and 11 and rails 1, 3 respectively, are held bolted sidewardly extending oppositely placed horns or hose clips lfor the purpose of holding cradled therein the delivery line when not in use, as will be further made clear. V

Held also to opposite sides of said castings 11 and 13 is a handle or grip 17 by means of which the greasing device as a whole may be lifted and transported about.

Bored lugs or ears 19 on the rear of the side frames 1 and 3 are adapted to rotatably receive a forgedhandle-bar 21 for purposes of drawing the pump about. The handlebar 21 is forged with downward extensions 23 which engage a pair of the said legs 5 of the rails 1 and 3 and prevent descent` of the bar to the door when said bar yis not in use (see Figs. 2 and 5);

Referring now more particularly to the forward pump casting 11, it may be seen that said casting includes anges 25 whereby it is bolted to the sideframes 1 and 3, as described. Longitudinally and centrally of said ianges and formed 'therewith is a bored plunger cylinder 27 provided at its forward end with a. conventional ball check valve 29. As indicated in Fig. 2, the rear end of said plunger cylinder is formed 4as a. piain slide bearing 33. Around a more or less central portion of .and recrosses the space 35.

vided with a lid 41. The bottom 43 thereof is provided with` an opening 45 which aligns with the upper opening of the chamber 37 and is adapted to receive the conical rim of a strainer 47 therein.

Now, as will later be made clear, grease and the like is adapted to be drawn or forced from the container, through the strainer 47, passages 37,. 35, borev of cylinder 27, valve 29, to a supply line 49 (preferably flexible) made fast to the outlet end of the valved cylinder 27.

To accomplish the above purpose, a plunger 51 is caused to reciprocate in the bored cylinder 27 so that its forward end crosses The plunger is made to fit the cylinder 27 snugly and as J the plunger recedes rearwardly, the check valve 29 automatically closes. Hence, a vacuum is drawn in the cylinder 27 and as the plunger end recedes over the more -or less annular opening 35, grease rushes from all sides of the cylinder 27 and into said cylinder. At the next forward movement of the plunger the grease in cylinder 27 is forced through the cheek valve 29 and out into the line 49. In starting the device, it may be primed by pouring oil into the passages 35 by way of the container 39. If after la period of operation the device should lose it prime, priming may be accomplished by inverting said device, removing a plug leading to chamber 35 and pouring oil or the like into said chamber 35. This latter method of priming savesvthe operation of removing grease fromv'the container f39 in order to get oil into the passage 35.y

It is clear that the reciprocating action of the plunger 51 may be continued indefinitely to draw grease from .the container 39' and discharge it into line 49. In order to reciprocate the plunger, an air engine E is provided at the rear of the device. This engine is associated with, and cast (in part) with the said casting 13.

rlhe air engine E comprises a work cylinder 55 to which is longitudinally cast, on center line, a spring retaining cylinder 57. These cylinders are adapted (as a unit) to be aligned on center line with the cylinder 27, at least approximately.

Passing through the cylinder 57 and into cylinder 55 is a piston rod. 59. The rod 59 passes out of the forward end of said cylinder 57 and cooperates with the vplunger 51 by means of a counter bore and cross pin combination 61. The combination 61 is permarient but during assembly permits of some mis-alignment between the cylinders 55, 57 and 27, in so far as the counterbore in the shaft 59 may be made somewhat larger than the diameter of plunger 51.

At the rear end, the rod 59 is provided With :a driving piston 63. The piston comprises a backing plate 65, a leather piston 67 and a clamping cup 69, all held to a shoulder on rod 59 by meansof' a nut as shown. The cup 69 is flanged out farther than is the piston, so that the relatively soft piston can not strike the head 71 of the cylinder 55. The piston 63 is normally held moves with the piston rod 59. It isso supported for the said movement by screwing the rear end of it into the piston 63 and pinning the forward end into aV vertical bracket 77, which bracket is held by means of a tight lit, and set screw 79 to the forward jointed end of t-he piston rod 59. The said rod 75 slidably passes through a proper passage in thehead end of the cylinder 55 and is steadied by passage through an ear 81 at the front end of the cylinder 57. It`

is clear that by means of the construction described, the piston rod 59 can not twist out of its assembled position and a rugged aligning system is, provided for driving the valve gear to be described.

A crossshaped lug 83 is east on the top of the work cylinder 55. The lug is provided*- with a longitudinal bore 85 for slidably receiving a valve 87. Positive movementlimiting heads 89 and 91 are provided at the is interposed between the valve 87 and the interiorgof cylinder 55. T he exhaust passage 97 leads direct to the atmosphere and the inlet passage is provided with a conventional air inlet plug 103.

To bring air to the inlet passage 95 it is only necessary to hold a conventional air nozzle (such as is used for filling automobile tires and available at most garages) to the plug 103. The plug 103 and nozzle 105 mutually open one another and air may flow from the compressed air line 107, associated with said nozzle 105, to the inlet passage 95. The description of the plug 103 and nozzle 105 is not detailedhere, inasmuch ylil as their constructions and combinations are well known, conventional, and are not claimed herein to be new per se.

ln order to hold the nozzle 105 to the plug 103, a hinge block 109 is held to the lug 83 by means of a shoulder on the plug 103. To this block 109 is hinged an adjustable saddle member 111, 'which is adapted to swing over ily be removed by lifting, and whence air automatically ceases to flow from the nozzle 105, or to tend to flow into the passage 95.

Returning to the valve construction, the drawings (Fig. 2) show that the valve 87 is provided with a groove 115 adapted to register with the said inlet passage 95 and outlet passage 97 when the valve is in its maximum rearward and forward positions respectively. Hence, by positioning the valve 85 rearwardly,ithe exhaust passage 97 is closed, while the inlet passage 95 is opened whereby compressed air 'may pass from the line 107 through the open nozzle 105, open plug 103, passage95 and groove 115, passage 101, passage 99 and to the cylinder 55, where l work' is done to press the piston 53 forwardly against the action of spring 73. By this means' the plunger 51 is made to takea grease forcing stroke as hereinbefore described. lient, hy positioning the valve 85 forwardly, the groove 115 aligns with the exhaust passage 97, as shown in Fig. 2, whereupcn the inlet passage 95 is `closed. This action permits movement of air from the cylinder through passages 99, 101, 97 and groove 115. Such movement of air is caused by the tendency of the air. to re'expand and the arpa-riding action N'of spring 73 which pushes the piston 03 rearwardly. The port 99 is near the. bead 71 so that the cylinder 55 may be substantially emptied of air.

Movement of the piston 63 and rod 59 rearwardly results in an evacuating stroke of plunger 51, whereby the grease cylinder 27 is again reloaded as hereinbefore described. l

In order to automatically position the valve 85 at its said maximum forward and rearward positions, so that pumping may be continuous when desired, the following fullstroke mechanism is used:

1Vertically fastened to the driving rod 75 is fastened a driving bracket 117 adapted to slidably engage the valve stem 93. Springs 119 and 121 are placed over said stem 93 rearwardly and forwardly respectively. These springs 119 and 121 respectively engage the said head 91 and another head 123 of the stem 13. Thel bracket 117 engages the springs in its travel back and forth along Vthe passages 95 and 97.

the stem 93. It is clear that upon engaging and compressing a spring to a given point, that the driving bracket (moving with the piston rod 59) will drive the valve rod 93.

In order to prevent the valve 87 from moving to reverse agiven stroke of the pis t0n G3 before the stroke is substantially finished, regardless of the predetermined length of said stroke, and to cause said valve t0 take a full stroke at every 'movement thereof, it is recessed at points 125 and 127. Corresponding points on the recesses area distance apart equal to the distance between Formed preferably horizontally across the valve passage 85, at a point corresponding to the position of recess 125 when the valve 87 is in forward position, isa passage 129 (see llig. 4). On each side of the valve 87 in the recess 125 is placed a ball 131. The balls are each backed by a compressed spring133 reacting against a retaining plug 135. llly this means the valve 87 may be resiliently held in either its exhaust or inlet position, depending upon which recess 1257er 127, the balls 131 are cooperating with.

lWhen the driving bracket 117 moves against the spring 119 (Fig. 2) and substan tially compresses it, the rearward motion of the pist-on 63 is adapted to be aboutcom` pleted. In the meantime theorecess 125 and 'balls 131 have caused the valve87 not to be moved, despite the partial compression of spring 119. Finally at or near the end of the stroke of piston 63, the spring is adapted to have been compressed enough to overcomethe holding power ofthe balls 131, and the valve 87 moves under action of the 'spring 119. The valve must move rearwardly its full stroke` because, as the high ridge 137 between the recesses 125 and 127 passes the balls 131, the inward movement of the balls into the recess 127 forces the valve to full stroke position as described, although the spring 119 may by this time have expanded to such a position that it would not, without'the full stroke feature, be able to move the valve to a position such that the groove 115 aligns with port 95. Of course, as the valve opens the inlet air port 95, the motion of the piston is reversed to a forward direction, and reversal of the above events takes place. This time., however, the spring 121 comes into play, while spring 119 is idle. The reverse events will be obvious from the foregoing.

It is evident that if the nuts 123 are re-set, that the stroke of the piston 63 will be varied because theaction of the moving piston on the full-stroke valve is effective at a different period of piston movement, that is, on the outgoing stroke. 4 f

The pumping action by means of the engine E is then continuously automatic as long as certain other events, to be described,

ceases to operate because grease cannotbe ejected with the normal air pressure available. It the line is opened of course grease can pass and the air engine automatically commences operation and continues operation until said line is again closed. There is no dead point from which the operation of the engine could not `be started. It the engine is exhausting when valve V is closed the spring 73 continues forcing the `,piston toward the head 71, in so tar as the rearward action of plunger 51, due to the check valve 29, is independent of conditions in line 49. The piston is then ready for forward travelj whenever the line 49 is opened to permit the predetermined air pressure in line 107 to taire eitect. The tact that the air'engine can be stopped'by closing valve V does not imply that only low grease pressures are attainable in the outlet line 139 leading from the valve, for it the saidwline 139 is connected with nearly clogged bearings, ,several thousand pounds per square inch of pressure may be brought to bear on the-obstruction with only a nominal air pressure inV cylinder 55. 'lhis is due to the ratio ot the diameters ot piston 63 and plunger 51. The closing ot valve V however, resists the high pressure.

lEig. 5 indicates the complete assembly of the apparatus and illustrates in ,dotted lines how the delivery line '49 is laid away in the horns or clips 15 when not in use. The apparatus may be towed about by means ot the forward handle-bar 21, or carried by means et the upward handle 17. Movement from one air linesuch as line 107, to another lilre one is readily accomplished merely by loosening one line and applying the other. No manually operable valves can be lett open. The device is simple in application in so far as there are only obvious operations to be performed byan operator.

In view of the above, it is believed that the various features of this invention will be clear without'turther elaboration, and it will be seen that with the apparatus -herein described, the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above construction without de- June, 1920.

parting trom the scope ot the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim: v

1. The airfengine comprising a cylinder, a reciprocating piston therein having a rod thereon reaching-through a retaining cylinder, a return spring within said retaining cylinder on one side ot the piston tending to press said piston in one direction, a Jr'ullstroke valve gear adapted to pass compressed luid to and from the other side of the piston, full stroke automatic means controlling the character of the movement of said valve gear to move it to its extreme positions, lost-motion connecting means between the valve gear and the piston, said connecting means including means tor adjusting the piston stroke and means associated with said retaining cylinder tor maintaining alignment between the piston and valve gear. y, 2. An auton'i'atically operable air engine comprising a work cylinder having a longitudinal extension cylinder, a piston in said work cylinder and a piston rod therefor passing through said extension cylinder, a return spring surrounding said piston rod and seating in said extension cylinder, a driving stem joined to said piston' and passing trom the work cylinder, means on the extension cylinder tor slidably supporting said stem, a valve including a valve stem adapted to permit passage ot air to and from one side of the piston and operable by a bracket connecting said driving stem and said valve stem, whereby positive alignment between the piston rod and said valve stems is maintained.

3. An air engine 'comprising a main cylinder, a reciprocating'piston therein having a rod thereon, an extension cylinder joined with said main cylinder, said rod passing through the extension cylinder, a return spring within the extension cylinder and around said rod, tending to press said piston in one direction, a. valve gear admitting and releasing air from the side of said piston opposite said spring, a driving stem joined to and moving with said piston and positioned for movement outside of said cylinders, portions associated with said cylinders guiding said stem to prevent rotative movement ot' the stem, piston and rod, and driving means interposed between the driving stem and said valve gear.

In testimony whereof, I have signed my name to this specification this 23rd day of raamt s. saints.

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