US2408109A - Pump - Google Patents

Description

'w. F. THOMPSON Sept. 24. 19461 I PUMP Filed Maren 13, 1945 Patented Sept. 24, 1946 T OFFICE PUMP Willis F. Thompson, Portland, Maine, assignor to The Alden Speares Sons 00., Cambridge, Mass., 7

a corporation of Massachusetts Application March 13, 1945, Serial No. 582,559

3 Claims. (01. 103L478) The invention relates to a pump especially adapted for the delivery of corrosive liquids from containers, such as carboys. 1

Usually in pumps of this type thepumping operation is effected by a piston having a piston rod by which the piston is reciprocated within a chambered cylinder. 7 that it may be manually controlled,'extends outside the cylinder through a joint in an end piece, or head; which forms an end closure to the chamber of the cylinder. The joint, through which the piston rod slides, is open to the atmosphere, and customarily the joint is sealed in some way for preventing the escape of liquid from the a chamber of the cylinder when the piston is being operated, and compression is being developed within the chamber. The sealing of the joint may be effected in various ways; as bya packing formed by some suitable more or less elastic material unaffected by acid, and which snugly embraces the. piston rod sliding throughit. The

' difficulty with such a packing, however, especially when the pump is being used for pumping corrosive liquids, is that the packing is apt to go to pieces, or disintegrate. In such case the corrosive liquid within the cylinder of the pump, due

* to compression, is apt to spurt through the joint,

serious 7 thus deprived of its packing, andcause injury to one operating the pump. I

The object of the present invention is to eliminate this diificulty by providing a pump which needs no packed joint .for its piston rod; the elimination 'of packing being the objective purpose.

The invention can best be seen and understood by reference to the drawing in which-.

Fig. 1 is a vertical section of a pump embodying the present invention. p

Fig. 2 is a view partly in perspective of a portion of the pump shown inFig, 1', and which shows essentially the way in which the objective purpose of the inventionisaccomplished. Referring-to the, drawingfl represents the chambered cylinder of thepump. 'The top end of the cylinder is closed in manner later to be described.

The cylinder, for convenience in packing, is

preferably made in two sections, of which 2 rep-' resents the top section and 3 the bottom section. The two sections are united by means of an internal sleeve 4 having a press fit into the top end of the section 3, and threaded fit, into the adjacent bottom end of section 2. V

The cylinder as a whole is made of some conslderable length in order that it may extend down The piston rod, in order to the bottom of the container(not shown) from which the liq id is to be Withdrawn, with upward extension well above the heador mouth of the container. The bottom end of the lower section 3 ofthe cylinder is provided with one or more cutouts 5 in order that liquid may enter the cylinder from the chamber of the container when the cylinder is resting on the bottomof the container. Y

The cylinder is provided at the lower end of its section 3 with an inwardly opening valve which allows the entry of liquid from the container upon the upward stroke of the piston, later to be referred to, but closing upon its downward stroke. The valvular structure comprises a valve seat 6 having a press fit within the cylinder. 1 is the valve adapted to have opening and closure with relation to this seat. The stem 8 of the valve extends through the annular seat, and isprovided with a cross pin 9 which engages the seat and limits the extent of opening of the valve as the valve is drawn to an open position.

In its top end portion the cylinder is provided exteriorly with a sleeve or jacket I!) which has a press fit against the adjacent portions of the cylinder which it embraces. The jacket extends upwardly beyond the end of the cylinder, thus providingan annularsocket I l At its top end the cylinder is provided with a baffle I2. ,This is seated to bear against the top end ofthecylinder, and is held securely in place by an annular Washer l3 contained within the annular socket llwith press fit against the adjacent top end of the sleeve or jacket l0.

Located within the cylinder, below and spaced from the baflle I2, is a deflectingwiper plate M. A chamber I5 is formed in the cylinder between the baffle and the plate. The wiper plate is preferably, an inclined plate, inclined at substantially an angle of In order to insert the wiper plate the top end of the cylinder is made sectional, there being provided an angularly cut end piece 2' ;wh:ich-is held securely in place for retainingjthe deflecting wiper plate by the surrounding sleeve or jacket l0.

Extending from the cylinder adjacent the wiper plate is a pourout nozzle or spout l6 through which the liquid exitsfrom the chamber of the cylinder. The spout is preferably of a relatively large outlet capacity. The inner end of the spout extends through the cylinder and the jacket and makes threaded connection therewith, thereby assisting in holding the jacket securely in place.

Surmounting thetop'endl of the cylinder and having substantially its same tubular form, is a ates an annular valvular head 22 having a stem 23 which extends into the end of the piston rod and to which it is secured by a cross pin 25. The pin 25 lies above the sleeve 2|; the head 22 below it. The diameter of the head, as well as the length of the pin, is less than the diameter of the cylinder. The head is of such diametrical extent, however, and the pin is of such length, that they will, respectively, engage the sleeve for moving it within the cylinder when the piston is reciprocated. The head is spaced from the pin a distance longer than the length of the sleeve, so that when thepiston rod is raised the head will be brought into closed engagement with the bottom end of the sleeve. The combined head andsleeve will then operate as a piston and induce a partial vacuum in the chamber of the cylinder below the piston, causing liquid in the container to enter the chamber by way of the valve 1, then drawn open, and filling the chamber of the cylinder up to the point of the ascending piston. During this operation undisplaced liquid contained in the chamber of the cylinder above the ascending piston will be forced to outlet through the spout l6. Upon the return of the piston, through lowering of the piston rod, all inflow of liquid from the container will cease. The valve 1 will be closed. The head 22 will separate from the sleeve thereby forming a communication through the piston so that liquid in the chamber of the cylinder lying below the piston may enter that portion of the chamber of the cylinder lying above the piston. The pin 25 will be brought into engagement with the sleeve, moving it downwardly through the chamber of the cylinder to the limit of the downward stroke of the piston rod, which is limited by the engagement of its hand grip IS with the top end of the cylinder, entering through the socket ll at the top end of the cylinder.

In. the operation of the pump during the upward stroke of the piston, especially if the piston is rapidly reciprocated, considerable liquid pressure will be formed in the chamber of the cylinder although the ample capacity of the spout will assist in relieving this pressure.

I Liquid clinging to the piston rod as it is. raised to pass through the deflecting plate I4 will be struck by the deflecting plate and in large measure be wiped off the rod. This efiect is enhanced by the angularity of the deflecting plate which is preferably angularly arranged, as previously explained. Liquid that is not wiped off by the deflecting plate, and remaining upon the piston rod, will, due to its surface tension, assume in the chamber [5, droplike or cylindrical shape which is effectively stripped from the piston rod by the baflie l2. In consequence, though some slight moisture may remain upon the piston rod beyond and above the baffle, yet spurting of the liquid is entirely eliminated and danger of such avoided. Any liquid that may accumulate in the socket I I above the baflle may escape, into the chamber I5 below, by way of a small opening 21 at the side edge of the baffle. Liquid accumulating within the chamber [5 between the deflecting plate and the bafile will be drawn out of this chamber through a small opening 28 at the extreme bottom end of the chamber on the downward stroke of thepiston. r

I claim:

1. In a pump having a cylinder and operating mechanism which includes a reciprocating piston and piston rod, means forming an end closure for tl e cylinder through which the piston rod slidably extends, and comprising a baffle plate and a deflecting plate both fixedly arranged within the cylinder and spaced from one another to form with the cylinder a chamber interposed between said plates, the deflecting plate forming the bottom of said chamber having within it a vent opening by which liquid accumulating within the chamber may be withdrawn from it during the downward reciprocation of the piston. I

2. In a pump having a cylinder and operating mechanism which includes a reciprocating piston and piston rod, means forming an end closure for the cylinder through which the piston rod slidably extends, and comprising a baflle plate and a deflecting plate both fixedly arranged within the cylinder and spaced from one another to form with the cylinder a chamber interposed between said plates and having within it a vent opening by which liquid accumulating within said chamber may be withdrawn from it during the downward reciprocation of the piston, the bafiie plate forming the top of said chamber'occupying a position substantially normal to the line of movement of the piston rod, the deflecting plate forming the bottom of said chamber being arranged in an angularly inclined position with relation to the line of movement of the piston rod.

3. In a pump having a cylinder and operating mechanism which includes, a reciprocating piston and piston rod, means forming an end closure for the cylinder through which the piston rod slidably extends, and comprising a baiile plate and a deflecting plate both-fixedly arranged within the cylinder and spaced from one another to form with the cylinder a chamber interposed between said plates, the baflle plate forming the top of said chamber occupying a position substantially normal to the line of movement of the piston rod, the deflecting plate forming the bottom of said chamber being arranged in an angularly inclined position. with relation to the line of movement of the piston rod and having within ita vent opening by which liquid'accumuiating within said chamber may be withdrawn from it during the downward reciprocation of the piston.

. WILLIS F. THOMPSON.

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