US109732A - Improvement in air-pumps - Google Patents

Description

To all whom it may` concern:

` chusetts, have invented Improvements in Pumps for y strain and thck momentum which they acquire in their luist 6%ttttt Letters Patent No. 109,732.

dated November 29, 1870.

IMPRCVEMENT IN AIR-PUMPS.

The Schedule referred to in these Letters Patent and making part of the same.

Bc it known that I, JonN F. HAsnnvs, of' Fitchburg, in the county of W'orcester and State of' Massa- Oompressing Air; and I do hereby declare that the following, taken in connection with the drawing which accompanies and forms part of` this specification, is a description of my invention suiiicieut to enable those skilled in the art to practice it.

In compressing airinto a receiver, wh'ere it is stored and from which it is drawn and used as a motor, the valves ot' the pumps employed are subjected to great strain, and are citen broken, consequent upon such rapid reeil'n'ocations, and, when broken and displaced, are jammed between the pump-'piston andthe pumphead, causing breakage ot' the pump-cylinder or its vhead or the pump-piston.

This invention maybe stated as an ilnprovemeut upon the valvulararrangement shown in the United States Patent No. 93,051, datedV July 2.7, 1869, in' which is shown an air-pump, designed for the purpose of compressing air into a receiver.

My invention consists, firstiu such a construction and arrangement that, while the spindle or stem, commonly made on the piston-valve to guide th'e valve in its movements and moving with the valve, is dispensed with, my piston-valve, which is k'cpt in place by a ccntral guide ixcd to the piston, will not, in rising or falling, hind upon such guide, even although it does not maintain a horizontal position in rising orv falling. This I accomplish by giving to the central guide of the valve fixed to 'the piston a convex outline, so that, if the valve tilts in rising or falling, or, in other words, if one cdgc of the valve moves and the other remains on the valve-seat, the valve will not bind or jam on thc central guide, but will freely move 'over it.

The convexity of' the valve-guide is made to eorre. spond to lines described by radii which reach f'rom the outer lower` edge ci' the valve to the further boundary otthe central hole in the valve encompassing the guide. W hen the pistou or inlet-valve has been made with a spindle fixed to and moving with the valve, the metal of the valve is strained each time the valve closes by resisting the momentum ot' the spindle, which has a tendency to break down through t-he valve. \Vhen the valve is checked in rising the tendency is to tear the value away from the spindle in an upward direction, so that, when a light thin valve has a spindle moving with it, it is only a question of time when the valve and its spindle will separate. As it is a matter oi considerable practical import-ance to make the inlet piston-valve quite thin and 1ight,to prevent pounding of the valve, itis found to be a desideratum to guide and confine the valve at its center without afa-i taching to it a spindle, and it' has hitherto been considered impracticable to use a thin value, guided aud confined by a fixed central spindlel because of' the griping of said fixed spindle by the valve, consequent upon its not moving with perfect parallelism to its seat. But, by making the fixed central guide with a convex outline, as described, I am enabled to dispense with central spindles moving with the valve, and to prevent the valve, without such moving spindle and moving ovcr'a -fixed central guide, from sticking or binding on said guide.

In the patent before referred to it will be seen that the upper or delivery-valve has a seat which projects inwardly beyond the periphery of the piston, and that said seat is confined between the upper end of the pump-cylinder and a chest, from which the air-pipe leads to the receiver. In said arrangement, if it becomes necessary or desirable to take the'piston out of' the pump at its upper end, as .is frequently the case, y this can only be done by disconnecting the air-pipe between the pump-chest and the receiver, and tak-ing off said chest, which involves so much labor. that the apparatus is often allowed to ru'u for some time after it needs attention to itspiston or piston-valve.

Now another part of' my invention consists in the arrangement, herein described, of the pump-chest, delivery-valve seat and valve, and upper head, so that said valve-seat and valve and the piston and pistonconnecting rod and vaivc, can all be withdrawn upward from the pump-cylinder on removal of the head, and disconnecting the comiecting-rod'from its crank, and without disturbing the connecting-pipe between the pump and the receiver. Moreover, if between the upper part of the piston and the under surface of the head any part gets loose or broken, or any obstruction is'lntrodu'ced, the bolts which hold the heat? in place will give way, and the delivery-valve and. val ve-seat will be saved from damage by being pushed' upward, the bolts which secure the head being proportioned to resistthc strain of actual work, and not to resist the strain which the pistou will exert ou foreign or misplaced bodies. f

1t is in the arrangement herein described and shown of the delivery-valve and valve-scat, the pump-chest and the chest or pump-head, 'by which, onthe removal of the said head, the delivery-valve and its seat can l be removed, allowing the piston to be withdrawn upward, when the connecting-rod is unc'oupled from the crank-pin, and by which the parts are saved from serious breakage by the giving way of' the head-bolts, that the second part ot' my invention consists.`

Figure 1 of the drawing shows,.in verticai central section an air-compressing pump, in which my invention is embodied.

Figure 2 shows, on a large scale and in vertical centrati (tithe tral section, the upper part of the pump-piston and the inlet-valve working therewith.

Figure 3 shows the dcliverywalve seat and valve combined in side elevation, the same being shown in plan' in Figure 4. v

The pump-cylinder f` is lnade integral with the chest k, the internal diaineter of which is greater than the bore of the pu1np-eylinder f, a groove being made in the inner all of the chest to serve as a passageway; with which the delivery-pipe p connects.

The delivery-valve seat his made, as a ring, with bars extending upward therefrom, so as to Iill the distance between the uppcrend of the pump-barrel and the lower side of the head j, so that the headj contines the seat h upon the upper end of the pump-bar rel. The bars from the pump-seat are turned concentric, both ont-side and inside, with the axis ofthe pumpbarrel, so that-the outside of the bars fits the space in the chest above and below the passage around the chest, and so as to guide the delivery-valve i, which is a short section of a cylinder with a closed bottom, on which bottom a valve-face is formed to it'the valveseat face. Between the top of valve t' and the lower surface of the heady space is allowed enough to permit the valve to rise the amount needed to permit the air to escape past the valve, and to liow through the spaces between the bars attached to the valve-seat h, through the passage or groove, around the chest 1.", to and out of the delivery-pipe p.

The piston l islike that shown in the patent alluded to heretofore, and is provided with awrist-pin, on, from which a connecting-rodo, passes to a crank-pin, d, which is lixed iu a crank secured to the main shaft b, on which is iixed the the engine-crank c. These condensing-pumps are usually and preferably connected in pairs and with a steam-engine, the cranks of the pumps and engine bearing the relation set forth in the aforesaid patent.

lhc inlet or piston-valve n is a thin plate perforated with a round hole, which embraces a guide, q, fixed in the piston, said ,guide baring a head which limits the amount of lift which the valve can receive relatively to the piston, which is made as a hollow cylinder, with a closed upper end perforated, to allow air to enter the cylinder by lifting-valve n as the piston makes its downard stroke.

This guide q is preferably made to screw into a hub on the under side oi" thcpiston-head, and between the upper side of the piston-head and the under side of the head of thc guide the outlineis turned to conform to circles, the centers of which are at or near the outer lower corners of valve n, so that, when-valve n assumes the posit-ion denoted by dotted lines in fig. 2, it will not gripe or bind upon the fixed central guide.

The guide q is screwed into the piston-hub to a shoulder formed on the guide, andthe guide thus forms a cover to an oil-reservoir, which is made by having the hole in the hub of the piston deeper than is needed for the guide, and holes are made through thc piston-hub into the oil-reservoir, to allow the oil to ilow upon and to lubricate the wrist-pin Imf. In practice `this oil-reservoir is supplied by a syringe from below, the pipe of the syringe beinlg,r made to enter ahole in the side ofthe hub just below the end of the guide q.

To facilitate drawing the piston and conneeting-rod upward out of the pump-cylinder I tap the guide q centrally to receive an eye-bolt, to which a tackle cau bc connected to lift ont of' the pump the piston and eoiniecting-rod.

I' claiml. rlhe centrally-lm-rlhrated disk-valve, in combination with a fixed central guide formed, substantially as described, in the part over which such valve mores in action, for the purpose specified.

2. lhc combination ot' t-he pump-barrel, chest, dclivcry-valve seat,delivery-valve, and pump or chest head, when arranged substantially as and for the purpose set forth.

JOHN F. HASKINS. Witnesses:

J. B. Gaosr, C. WARREN BROWN.

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