US 2388661 A
Description (OCR text may contain errors)
Patented Nov. 6, 1945 PUMP Joseph C. Woodford, Spring Lake, Mich., assignor to John Wood Manufacturing Company, Inc., Philadelphia, Pa., a corporation of Delaware Application January 9, 1945, Serial No. 572,019
' 3 Claims.
My invention relates to improvements in fluid pumps of the type which includes a piston arranged to be reciprocated in its cylinder by means of a manually operated pivoted lever connected to the piston rod.
Prior art pumps of this type of construction have no out board guide bearing for the piston rod, which results in an excessive strain being put on the packing gland, due to improper guiding of the piston rod, thereby causing an excessive amount of leakage, even to the extent of a jet or spout of liquid, from the top of the pump. Accordingly, prior art pumps of this type have been proven to be impractical for use in the handling of inflammable and hazardous liquids because of both the lire hazard involved and the hazard to the eyes and clothes of the user of the pump.
In my improved construction, I have overcome such faults by extending the contact area, or skirt, of the piston to the extreme lower end of the cylinder, while leaving the central portion of the piston sufciently high to allow clearance for the base valve. When the piston of my improved pump is at its extreme upward position, the leverage of the portion of the piston rod which extends in the open above the packing gland atl the top of the pump is not excessive as compared to the distance between the packing gland and the surface of the piston in contact with the cylinder wall. In prior art pumps of this type, there is excessive leverage at the packing and cylinder wall, which becomes critical quite suddenly when the condition of excessive leverage is approached. Under this condition, the piston breaks through the liquid at the point of contact with the cylinder wall which results in suddenly increased friction which in turn causes greatly increased pressure against the piston rod packing and the packing nut. Such condition results in unsatisfactory operation of the pump, excessive wear and leakage through the packing, with the attendant hazards and eventful bending of the piston rod.
Another feature of my invention is that the downwardly extending skirt of the piston is arranged to engage stop lugs in the base casting, thereby limiting the downward stroke of the piston rod to prevent the upper end of the handle from striking and damaging the packing nut.
Another feature of my invention is that the lever handle is constructed from ordinary steel pipe formed to the desirable shape and flattened and slotted at the upper end to provide for a pivot pin for the piston rod eye. Bushings and bearing lugs of greater thickness than the wall thickness of the pipe are welded to the pipe to form the necessary bearing area for the pivot pin. The use of a lever handle formed of ordinary steel pipe, instead of cast iron, results in lower cost, a better and more comfortable grip for the hand at any point on the lever, and less fatigue in operation due to less Weight being raised at each stroke. The use of ordinary steel pipe also precludes the possibility of inlever and its appurtenances omitted for purposes of clarity. Y
Fig. III is a side elevation of the dle shown in Fig. I.
Referring to said drawing; my improved fluid pump includes the base member I which is provided at its lower end with the external screw thread 2 adapted for engagement with a screw threaded opening formed in a tank containing the uid to be pumped. I nd it convenient t0 provide the screw thread 2 with the locking nut 3 for securely holding the pump in positionon the fluid tank, or container.
The lower end of said base member I is provided with the internal screw threaded inlet opening 6 which is adapted to be engaged by the threaded end of a depending inlet pipe which extends to near the :bottom of the tank. 'Ihe base member I is provided with the air vent 9, the upper end of which is open to the atmosphere at a point above the lock nut 3. Said air lever han- Vent 9 affords open communication between the atmosphere and the topof the tank container.
The base member I is provided `with the valve seat YI 0, conveniently circular in conguration, for the base valve II. Said valve II is rigidly fastened to the upper end of the valve rod I2 by means of the nut I3. Said valve rod I2 is mounted with freedom of reciprocatory movement in the bearing I5 formed in the web I6, which web I6 is formed conveniently as part of the base member I and is located above the chamber I'I of said base member. The chamber I'I is in open communication with the screw threaded inlet openingv 6 in the base member I. Said web I6 is provided with a series of openings 20 therethrough for the passage of fluid through and around the valve seat IIJ and the valve II when the valve II is in open position. Upward movement cf the valve II is conveniently limited by means of the flange ZI, formed on the lower end of the valve rod I2, coming intoengagement with the under.`
side of the web I E.
Said base member I is provided with an annular recess which forms the seat for the lower end of the piston cylinder 26. I find it convenient to interpose the gasket 21 between the lower rend of the cylinder 26 and its seat 25. The upper end of the cylinder 26 is seated in the annular recess 30 formed at the bottom of the top casting 3 I. I nd it convenient to interpose the gasket 32 between the piston cylinder seat 30 and the top of the piston cylinder 26.
Said top member 3l, piston cylinder 26, vand base member I are maintained in rigid fluid tight relationship by means of a series of tie rod bolts 35, the Screw threaded lower` ends of which are engaged in the screw threaded bosses formed on the base member I. The upper ends of said tie rod bolts 35 extend `through Vdrilled openings formed in the bosses 31 which .are formed on the lower portion of the top member 3l. Ihe piston 40, arranged to be reciprocated in the piston cylinder 26, is provided with the depending skirt portion 4I, which has at its vlowerend a depending ange 42 provided with an .annular .recess 42' in which is mounted `the piston ring 43, or any other of the well known means for preventing the passage of fluid between the piston and piston cylinder. The piston is rigidly .fastened to the lower end of the piston rod 45 by means of the nut 46 and lock washer 41.
The upper end of the piston 40 is provided with the annular valve seat 5D which is engaged by the valve 5I. Said valve 5I is provided with the axial opening 52 and is mounted with freedom of movement on the piston rod 45. As shown in Fig. I, upward movement of the valve 5I on the piston rod 45 is conveniently limited by means of the pin 53 which is rigidly mounted in the opening 54 Vformed in the lower end of the piston rod 45.
The skirt portion 42 of the piston 40 is pro vided with the extension 5B which is adapted to of ordinary steel pipe formed to the desirable shape. As best shown in Fig. III, the end of said. pump handle 16 is flattened and slotted, with thebifurcations thereof engaging the piston rod eye 18 formed at the top of the piston rod 45. The opposite flattened sides of the handle 16 have bearing lug bushings 80 Welded thereto, as best indicated in Fig. III, to provide the necessary bearing area for the pivot pin 8| which extends through `said bearings and the piston rod eye.
The handle 16 is provided with two fulcrum clips 82 lwhich are formed as separate pieces and welded or brazed to said handle 16. The upper end of the .lever link 83 is engaged between the fulcrum clips 82 and pivotally connected thereto by means of the pin 85 which extends through openings formed in said clips and in the top of the lever link 83. The lower end of said lever link 83 is bifurcated and pivotally connected by a pin to the lug 89 formed on said top cover 3l. The outer -end of said lug 83 acts as a stop for the handle 16 to limit the upward str-oke of the piston.
The handle shown and described .herein is claimed in my divisional application Serial No. 584,538 iiled March 24, .1945.
When the piston 40 is at its extreme upward improved skirted piston. In prior art pumps lof this type which embody pistons of the ordinary construction, the ratio is approximately 5 to l A in pumps of equivalent size and capacity.
engage a series of stop lugs 51, conveniently formed as an integral part of the base casting I, when the piston 40 is in its 'lowermost position as indicated in dotted lines in Fig. I.
As shown in Fig. I, the piston skirt 42 has the general conguration of ka truncated cone which affords clearance between the central portion vof the piston v4I) and the base valve II when the piston 40 is in its lowermost position as indicated in dotted lines in Fig. I.
The top casting3| is provided with the axial drilled opening G0 which .forms a bearing for the piston rod 45. Said piston rod 45 is provided with the packing gland 62 formed in the top .casting 3I. Said packing gland is of ordinary construction and includes a series .of layers of packing 65 and the packing gland nut 61 in screw threaded engagement in the opening formed in the top of said casting 3|.
As best shown in Fig. II, the top of the top casting 3| is provided with the ,outlet pipe 1I) which is in rigidly screw threaded relation in the boss 12 formed conveniently as an integral part of said top casting 3l. The upper end of Isaid outlet pipe 10 is connected to the U-shaped outlet fitting 13 which includes an air vent assembly of the well known construction. A dispensing hose (not shown) is connected to the outlet iitting 13, and the distal end of said hose is provided with the dispensing nozzle. Said outlet .tltting 13 is provided with one of the well known forms of protecting cover and nozzle support for holding the nozzle when the pump is not in use.
The upper end of the piston rod 45 is pivotally connected to the pump handle 16 which is made I nd it convenient to provide said handle -15 with the locking clip 9B which has the opening 92 therethrough which, when the pump handle is in the position shown in Fig. I, is in matching relationship with an opening formed through the lever link 83. The hasp Vof a lock may be inserted through the opening 92 and the matching opening in the lever link 83 when the pump handle is in the position shown in Fig. I, .and thus prevent unauthorized use of the pump.
It is obvious that various modilcationsmay .be made in my invention withoutdeparting from the essential features thereof as defined in the appending claims, and, therefore, I Vdo not desire to .limit myself to the precise details .of construction and arrangement as herein set forth.
l. A piston `for a ,-iluid pump wherein the piston is arranged to be reciprocated in a ycylinder by means of a ymanually operated lever handle connected to the piston rod comprising an upper reduced portion having a valve seat formed at the upper part thereof; an intermediate piston skirt of the general `configuration of a truncated cone; and a lower ange portion provided with means for forming a seal between said piston and the wall of said cylinder.
2. A structure as in claim 1'; wherein said lower iiange portion includes at the bottom thereot means for .engaging a series of stop lugs formed in `the base of said pump.
3. A structureas in Iclaim l; wherein `said lower flange portion includes :at the bottom thereof stop means for engaging .stop means in the 4base olj said. pump.
. .JOSEPH c.- wooDFoRn.