US 952440 A
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Description (OCR text may contain errors)
C. B. DALZELL.
APPLXGATION FILED MAY 26,1909.
Patented Mar. 15,1910.
2 sHBETsf-SHEBT 1.
aval C. B. DALZELL.
APPLICATION FILED MAY 26,1909.
Patented Mar. 15, 1910,
2 SHEETS-SHEET 2.
' durable construction and involves erases i.
CHARLES B. DALZELL, LITTLE FALLS, NE'W YORK, ASSIGNOR TO D. H. BURRELL 8c COMPANY, OF LITTLE FALLS, NEWT YORK.
Specification of Letters Patent.
itatenieu atar. i5, itil-til.
Application filed May 26, 1909. Serial No. 498,497.
To all who/m it may concern:
Be it knownl that I, `CHARLES B. DALZELL, a citizen otl the United' States, residing at Little Falls, in the .'connty of Herkimer and State of New York,l haveiiivented a new and useful improvement in Air-Pumps, ot which the following is a specification.
rlfhis invention relates more particularly to improvements in vacuumtpumps and has for one ot its objects to`prodnce an efficient andA desirablel pump which is of simple and the minimum number of parts.
Other objects of the invention are to so construct the pump that access can be readily had to the working parts thereof, vand that the valves can be quickly and easily removed, or the pump taken apart for cleaning, repairing or replacing any of the parts thereof without disturbing the pipe connections; and also to so construct and arrange the valves and their operating mechanism that while the operating mechanism is mainly inclosed in the pump casing, where it can be kept clean and thoroughly lubri: cated, the connections between the valves and their operating mechanism are located so as to be accessible and allow the valves to be removed and replaced with the least delay and" orlt.
In the accompanying drawings,consisting of two sheets: Figure l is a longitudinal sectional elevation oi a vacuum pump embodying the invention. Fig. 2 is a sectional plan of the base 'thereof in line 2-2, Fig. 1. Figa v3 is a transverse sectio;\al elevation of the pump in line 3 8, Fig. l. Fig. i is an end elevation thereof, partly in section, in line LH-4, Fig. l. Fig. 5 is a perspective view et' the valves detached. Fig. 6 is a fragmentary end elevation of the pump.
Like reference characters refer to like parts in the several figures. i
A multiple cylinder pump is shown in the drawings. A and A represent the cylinders, B and B the pistons, C the crank shaft having opposite crailk portions connected to the pistons by pitmen D and D, andl E and E are combined inlet and outlet valves for the cylinders A and A, respectively.
The pump casing or body comprises base, intermediate and top sections a, a and a2, respectively, which are separate from each other and are bolted or otherwise detachably semired together. The cylinders A A are.
formed in the intermediate section a. Their' lower ends are closed by the base section c and their upper ends open into a crank chamber c formed by the upper end ofthe intermediate section and the top section u2. An opening 'c3 is provided in the top ot the casing through which access can be had to the crank chamber and cylinders, and which is closed. by a loose cover plate 0.,
The crank shaft C is journaled at its ends in bearings c at the opposite sides ot the casing, formed partly by the intcwncdiate section c. and partly by the top section a, so that the crank shaft is released and with the pistons can be littcd out oi the casing when the top section (E :is removed.
The valves E 'and E', which are o the oscillating piston type, are arranged end to end in a cylindrical chamber or opening E2 which extends through the base a parallel with the c 1ank shaft and is open at its opposite ends. The valves are of uniform` diameter' throughout their length and can be inserted into and removed froml the valve chamber through the open ends thereof. This valve chamber is located beneath and in close proximity to the cylinders A A and communicates with each cylinder through ports c and e controlled by the valves E and lC. In the position ot the valves shown in the drawings, which they occupy when the pistons are at the ends oi their strokes, the ports @and c are closed. By rocking the valves in one direction'from this position, notches e2 therein connect the ports c with an inlet passage j' in the base to admit the air to the cylinders, while by rocking the valves in the opposite direction, notches c therein connect the ports c with an outlet passage f in the base to exhaust the cylinders. Thus both the inlet ot' air to and the outlet of air from each cylinder is` controlled by a single oscillating valve. IThe inlet and outlet passages f and f lead respectively to inlet and outlet pipesF and F which are connected to the base section o, of the pump casing.
The valves are operated by cams G G which are secured to the ends of the crank shaft within the crank chamber c and bear against antifriction rollers 'at the upper ends Y ofl vertical push rods g and gf, which are dctachably connected at their lower ends by bolts g2, or by other suitable means. to links g connected to the outer ends of the valves It surrounding the push rods in the guidel pockets serve to hold the rods against the cams and to return the valves to the position from which they are rocked in one direction by the cams. The upper ends of the rods project from the guide pockets into the crank chamber for engagement with the cams, while the lower' ends of the rods extend from the guide pockets outside of the pump casing forA connection with the outer ends of the valves. By this arrangement the cams and upper ends of the push rods are inclose'd in the pump casing where they are protected from dust and kept thoroughly lubricated by the oil running down from the crank-shaft bearings, hut the connections between the lower ends of the rods and the valves are located outside of the casing so that'thc valves can be readily disconnected from the rods and pulled endwise out of the valve chamber .E2 without disturbing the push rods or other parts of the pump when this is necessary for cleaning the valves, or for any other reason.
rllhe operation of the pump is as follows: The cams G G are arranged on the crank shaft as shown in Fig. 4, which indicates their position when the pistons are at the ends of their strokes, and the ports e and e are closed by the valves. The crank shaft turns in the direction indicated by the arrow in Fig. 4. The cam G rocks the valve E and starts to open the porte to the inlet passage f as soon as the piston B starts on its up stroke, and the cam is so shaped that thevalve is opened Wide when the piston has moved but a very short distance and is held wide open until the piston nearly reaches the end of its up stroke, When the cam allows the valve to be closed gradually by its spring h, the valve not being fully closed, however, 'until the piston starts l'on its down stroke. During the down stroke of thepiston the cam allows the spring h to rock the valve farther in the return direction so as toy gradually open the port e to the outlet passage f. As the piston approaches the end of its down stroke the cam moves the valve to again close the outlet'port e. The valve for the other cylinder is operated in the same manner. By thus holding the ihlet open until the piston has actually begun its return stroke the inertia of the incoming air is utilized to till the cylinder, and as the valve does not open the outlet port e until the piston reaches that point in its down stroke at which the air in the cylinder has been compressed to atmospheric pressure, there is no tendency for the air to rush into the cylinder when the outlet is opened and thereby increase the work of the pump.
The cam permits only a very gradual return movement of the valve by the spring, and the cam and spring-operated valve work very smoothly at high speeds of the pump.
By the described construction of the pump .with the valves in the base and the pipes connecting with the base section independently of the valves, the crank shaft, pistons and valve-operating devices are very accessible and can be examined and cleaned at any time by simply removing the loose cover plate at, and if it is necessary to remove the crank shaft and pistons it is only necessary to detach the top section Z2 of the casing and lift the shaft and pistons out of the cas# ing. This could not be done if the pump were inverted or arranged with thevalves and pipe connections at the top of the casing. To remove the valves it is only necessary to detach their links from the push rods and slip the valves endwis'e out of the openended valve chamber, and neither the pipe connections nor any other parts of the pump have'to be disturbed. l,
In the pump shown, the crank shaft is provided with tight and loose pulleys l I', the latter being journaled on a detachable extension of the shaft consisting of a sleeve K secured to the end of the shaft proper by a cap screw /c and end plate 7c. When the loose pulley is not required, the extension sleeve K is detached and the end plate 7c is secured to the end of the crank shaft by a short screw. This construction may be employed or not, as desired.
L represents an 'oil drip pan which vis provided beneath the base section a. ot' the casing.
l claim as my invention:
l. ln a pump, the combination of a casi ng provided with a cylinder and with connections for the Huid at the base portion of the pump, a piston in said cylinder', a crank shaft removably journaled in the v casing above the cylinder and connected to the piston, a valve for the pump removably seated, in the base portion thereof, an operating device for said valve mounted on the crank shaft, and aconnecting` device actuated by said device on the crank shaft and detachably'connected to the valve outside of theA casing, whereby the crank shaft and piston and the yalve can be removed from the pump tifithout disturbing said fluid coni stl niovably seated in the base portion thereof,-
an operating cam for said valve mounted on the c ank shaft inside of the casing, and a pushiljod mounted on said casing and having` fits upper end enterinpr the easing for. engagement with said cam and its lower end, extending outside of the casing` and dei tachably connected tothe valve, whereby the crank shaft and pistonand the valve can be removed from the pump Without disturbing said fluid eomiections, and said valve can be removed when detached from said push rod Withoutdisturbingr the other parts of the pump, substantially as set forth.
3. ln a pump, the combinati-on of a easing provided with upright cylinders, -`and with fluid connections at the base portion of the pump, pistons .in said cylinders,U a crank shaft removably journaled in the casing above the cylinders and connected to the pistous, inlet and outlet valves removably seated in the base portion of the pump, op.-
erating cams for said Valvesmounted on the opposite ends of said crank shaft inside of the casing, and push rods mounted in bearii'igs on the opposite sides ofthe casing and having their upper ends entering the casingfor engagement with said cams and their lower ends extending outside of the easing and detachably connected to the outer ends of said valves, whereby the crank shaft and pistons and said valves can be removed from the pump without disturbing said fluid connections, and said valves can be removed when detached from said push rods Without disturbingthe other parts of the pump, substantially asset forth.
et. n a pump, the combination of a casing prtwidcd with yparallel upright cylinders, pistons in the cylinders, a crank .shaft jeun ytheiremo'val of the crank shaft and 11a-led in the casing` abovec-the cylinders and connected t6 the pistons, the casing;1 having an upper part `vhich is detachable to permit pistons, inletfavnd outlet valves for th cylinders ren'ioxfztb'ly seated in the base port-ion of the "casing, operating cams for said valves mounted on the opposite ends of the crtnk shaft inside of the casing, push rodsyt-arranged at the opposite sides of said easing which are actuated by` said cams and are detachably connected to said valves. and pipe connections for the pump at the base thereof, substantially as set forth.
5. In a pump, the combination of a easingl having' detachably connected top, bottoni and intermediate sections, said intern'xediate 'section having` a cylinder, and said bottom section ha ving an open-ended valve chamber, a piston in the cylinder, a crank shaft journaled in the casing' above the cylinder and being remo 1able(.therefrom by detaching the top section of the casino, an oscillating valve in said valve chamber andl removable through the open end thereof, an operating,` cam for said valve on the crank shaft, a push rod which is actuated by said cam and is detachably connected outside of the casing with said valve, andI pipes connecting with said base section] of the easing, IWl'lereby the crank shaft, piston and valve can be removed without disturbing the pipe connections, substantially as set forth.
lWitness my hand, this 19th day of May, 1909'.
l CHARLES B. DALZELL.