US3026813A - Cutting plunger pump - Google Patents

Description

March 27, 1962 L. M. NECHINE 3,026,813

CUTTING PLUNGER PUMP Filed March 7, 1955 5 Sheets$heet l g? EwaL/m," QTXWW'KZ 772/. 7Zc fukac 6/? m1 aw I) March 27, 1962 L. M. NECHINE 3,026,813

CUTTING PLUNGER PUMP Filed Mai'ch 7, 1955 5 Sheets-Sheet 2 I March 27, 1962 1.. M. NECHINE CUTTING PLUNGER PUMP 5 Sheets-Sheet 3 Filed March '7, 1955 March 27, 1962 L. M. NECHINE 3, 26,813

CUTTING PLUNGER PUMP Filed March 7, 1955 5 Sheets-Sheet 4 ELI/01m" sfzmwxa 77a 7Z6GIQQZE/ 7 QMMMM 117 214 [647 March 27, 1962 L. M. NECHINE CUTTING PLUNGER PUMP 5 Sheets-Sheet 5 Filed March 7, 1955 I rim. K v Iin L java Jamal/rd 77$. nae/warp, (L/ MZGL dC I fl 3,926,8l3 Patented Mar. 27, 19 62 mesne assignments, to FMC Corporation, a corporatron of Delaware Filed Mar. 7, 1955, Ser. No. 492,585 2 Claims. (Cl.103-157) This invention relates to a valveless revolving piston cutting plunger pump that is particularly adapted to pump heavy and viscous liquids and sludges, such as sewage, which may contain some solid matter, and to out such solid matter and thereby prevent clogging of the pump.

In the pump constructed in accordance with the present invention the piston is provided with a continuous cam groove which engages a fixed cam follower to reciprocate the piston longitudinally as it is rotated by the driving mechanism. The piston rotates 180 in the same direction for each stroke in a single direction, and makes a complete ervolution as it travels through one complete reciprocatory cycle.

The piston is driven by a motor through a worm and worm wheel. The piston is in the form of a hollow cylinder and is provided with a port opening extending through the cylindrical wall. As the piston travels towards the driving mechanism it gradually opens and then closes the suction port by revolving the piston port past the inlet port of the cylinder. On the return or compression stroke the piston gradually opens and then closes the discharge port of the cylinder by revolving the piston port past the discharge port of the cylinder. In pumping sewage, or other liquids containing solids, a pump of this type may frequently become clogged by reason of some solid material, such as a rag, for instance, becoming caught between the piston and the cylinder. Any solid matter that prevents the closing of the intake port or the outlet port on any stroke interferes with the pumping action and may render the pump inoperative.

The present invention contemplates the provision of a renewable sleeve in the cylinder. The sleeve has two openings registering with the intake and outlet ports of the cylinder so that it serves as a lining for the cylinder. Preferably the entire sleeve is hardened, but in any event the edge portions contiguous to the openings are hardened. The piston has a very close peripheral clearance with the sleeve, and the edges of the piston contiguous to its port are hardened. When the edge of the piston adjacent its port approaches the edge of the sleeve adjacent one of its openings to close said opening the two hardened edges are in planes so close together that they produce a cutting or shearing action on any solid matter caught between the two edges. Thi cutting or shearing action permits the pump to close completely at each stroke and prevents clogging of the pump. If the sleeve becomes worn enough to lose its effectiveness it may be removed and replaced by a new sleeve.

The pump may be used in multiple arrangement by providing a double extension of the worm shaft, and manifolds for the suction and discharge ports of the cylinders. The pump is designed so that it may be mounted with the inlet and discharge openings arranged either horizontally or vertically. When the pump i used as a single unit its inlet and discharge openings normally are disposed horizontally, but when a plurality of the pumps are used in multiple arrangement the intakes and outlets must be disposed vertically in order to permit operation of all pumps by a single horizontal drive,

The structure by which the above and other advantages of the invention are attained will be described in the following specification, taken in conjunction with the accompanying drawings showing three preferred illustrative embodiments of the invention, in which:

FIGURE 1 is an end view of a pump embodying the invention arranged for use as a single unit, with intake and outlet openings disposed horizontally and the motor mounted vertically;

FIG. 2 is a front view of the pump shown in FIG. 1;

FIG. 3 is a front View, similar to FIG. 2, except that the pump is rotated axially through 90 to dispose the intake and outlet vertically;

FIG. 4 is a horizontal longitudinal sectional view, taken along the line 44 of FIG. 2;

FIG. 5 is a fragmentary view, similar to FIG. 4 as the piston approaches the end of its compression stroke;

FIG. 6 is a vertical sectional view, taken along the line 6-6 of FIG. 4;

FIG. 7 is a detail perspective View of the piston;

FIG. 8 is a vertical sectional view, taken along the line 88 of FIG. 4;

FIG. 9 is a vertical sectional view, taken along the line 9-9 of FIG. 4;

FIG. 10 is a fragmentary vertical sectional view, taken along the line 1ti10 of FIG. 5, showing the cutting and shearing action of the piston and the hardened sleeve;

FIG. 11 is a vertical longitudinal sectional view through a pump mounted for multiple installation, showing the extended drive mechanism;

FIG. 12 is a fragmentary horizontal sectional view of the pump of FIG. 11; and

FIG. 13 is an end view of three pumps mounted as a multiple unit, showing manifolds connected to the intakes and to the outlets of the pumps.

Referring to the drawings, the reference numeral 2 indicates a gear case mounted on a base 3 by means of bolts 4 extending into threaded recesses 5 in the bottom 6 of the gear case. A side wall 7 of the gear case is also provided with threaded recesses 8 to permit the housing to be rotated 90 and mounted on base 3. Base 3 is provided with apertured feet 10 which may be bolted to the floor. A cylinder 11 is secured to one end of gear case 2, The adjoining ends of gear case 2 and cylinder 11 are provided with abutting flanges 12 and 13, respectively. Bolts 14 secure flanges 12 and 13 together. The opposite end of cylinder 11 is closed by a cover plate 15 secured thereto by bolts 16. Cylinder 11 is provided with an inlet opening 17 and an outlet opening 18 arranged diametrically opposite each other. Normally the inlet and outlet openings are disposed horizontally, but, as shown in FIG. 3, the cylinder may be secured to casing 2 with the inlet and outlet disposed vertically.

As shown in FIG. 6, the driving mechanism comprises a motor 19 having a flange 20 seated on top of a flange 21 surrounding an opening 22 in the top of casing 2. Bolts 23 extending through flange 20 and threaded into recesses provided therefor in flange 21 secure motor 19 in place. A drive shaft 24 projecting from the motor extends through opening 22. A shaft 25 is provided at the end with a tubular enlargement 26 which fits over the end of drive shaft 24 and is secured thereto, as indicated at 27. The other end of shaft 25 is supported in a bearing 28. A worm 29 is mounted on shaft 25 adjacent the shoulder 30 defining the end of tubular enlargement 26. A collar 31 is mounted on shaft 25 between bearing 28 and worm 29. A nut 32 threaded on the end of shaft 25 holds worm 29 in place. A bearing cap 33, secured to casing 2 by screws 34 cooperates with nut 32 to hold bearing 28 in place.

Worm 29 meshes with a worm wheel 35 (FIG. 4) mounted on a hub 36 rotatably mounted in bearings 37 and 38. Bearing 37 is positioned on one side of worm wheel 35 and is held in place by a shoulder on one side of hub 36 and a shoulder formed on an interior sleeve 39 integral with gear case 2. Bearing 38 is positioned on the opposite side of worm wheel 35 and is held in place by a shoulder on the opposite side of hub 36 and a shoulder formed on an end closure 40 secured to the end of gear case 2 by bolts 41. The interior of hub 36 is provided with teeth 42 (FIG. 6) which are meshed with a splined shaft 43. End closure 40 is extended outwardly to provide clearance for splined shaft 43 which reciprocates through hub 36 is hereinafter described. Shaft 43 extends through gear case 2 and into cylinder 11. An annular oil seal 43' is provided between shaft 43 and the end of sleeve 39.

A renewable hardened sleeve 44 having an exterior diameter equal to the interior diameter of cylinder 11 is positioned within the cylinder and is provided with port openings 45 and 46 registering respectively with inlet opening 17 and outlet opening 18. A piston 47, having very close clearance with sleeve 44 is positioned within the sleeve. Piston 47 is in the form of a hollow cylinder having an end wall 48 provided with an aperture 49 through which the end of shaft 43 projects. A nut 50, threaded on the end of shaft 43, prevents relative longitudinal movement between shaft 43 and piston 47. The opposite end of piston 47 is provided with an annular packing gland 51 secured to the end of the piston by screws 52. Member 51 serves to hold a packing 53 adjacent its end of the piston. A similar packing 54 is held adjacent the opposite end of the piston by an annular packing gland 55. Piston 47 is provided with a port opening 56 in its cylindrical wall. The edges of piston 47 contiguous to port opening 56 are hardened for a purpose hereinafter disclosed.

A cam cylinder 57, having an end wall 58 and a laterally extending tubular portion 59 is rigidly secured to end wall 48 of piston 47. End wall 58 is provided with an aperture 60 through which shaft 43 extends, and is held against end wall 48 by a shoulder on shaft 43. A key 61, fitting into slots in shaft 43 and end walls 48 and 58 prevents relative rotary motion between shaft 43, piston 47, and cam cylinder 57. Packing 62 fitting into an annular groove in the outer surface of cam cylinder 57 engages the inside surface of gear case 2 adjacent its end. The outer surface of tubular portion 59 is provided with a continuous cam groove 63 (FIG. 7) which extends from a point adjacent one end of cam cylinder 57 to a point adjacent the opposite end, and then back to the first mentioned point as it extends around the circumference of the cam cylinder.

A cam roller 64 positioned in groove 63 is rotatably mounted on a stud 65 extending through one wall of gear case 2 and held in place by a nut 66. The diameter of cam roller 64 is substantially equal to the width of cam groove 63 so that the periphery of the cam engages both side walls of the groove. As shaft 43 is rotated through a complete revolution by the hub of worm wheel 35, cam roller 64 causes piston 47 to move a complete stroke to the left, as viewed in FIG. 4, and then back to its initial position. The stroke in one direction brings port 56 of the piston gradually into registration with inlet port 17 of cylinder 11 and then out of registration to close the inlet port. Any solid matter flowing into piston 47 as the inlet port is closed is caught between the hardened edge of port 56 and the edge of opening 45 in the hardened sleeve 44, as shown in FIG. 10, and is cut or sheared by the interengagement of these edges. The same type of action takes place on the return stroke when port 56 moves out of registration with outlet port 18. The continuous opening and closing of ports 17 and 18 in sequence as the piston rotates and reciprocates produces the desired pumping action, and the sharp hardened edges of port 56 engaging the hardened edges of openings 45 and 46 insures the cutting or shearing of interengaged solid matter and the complete closing of the ports on each stroke, and prevents clogging of the pump.

The hardened sleeve and the hardened edges of the piston contiguous to its port opening 56 resist the abrasive action of the liquid being pumped. If sleeve 44 becomes worn it may be removed and replaced by a new sleeve.

The modification shown in FIG. 3 operates in exactly the same manner as in the pump hereinbefore described, since the only difference is in the vertical disposition of the inlet and outlet openings, and, therefore, no additional description is required.

In FIGS. 11 to 13, a multiple installation is illustrated. In this embodiment each pump is rotated through to rest on its side 7 with bolts 4 extending through base 3 into recesses 8 to secure the pump to the base. The motor is mounted horizontally and its shaft 24 is secured in a coupling 67 instead of in the tubular enlargement 26 of shaft 25 as in the previous embodiment. Coupling 67 projects through a bearing cap 68. An annular plate 69 secured to flanges 21 by bolts 23, covers the outer portion of the opening encircled by flanges 21 and provides a smaller opening 70 to receive coupling 67 and bearing 71. Bearing cap 68 is secured to'plate 69 by screws 72.

At the opposite side of gear case 2 bearing cap 33 is replaced by a bearing cap 73 having a central aperture 74 protected by an oil seal 75. Worm shaft 25 is replaced by a shaft 76 of greater length. One end of shaft 76 is mounted in coupling 67. The other end of shaft 76 extends through oil seal 75 and aperture 74 and is secured in another coupling 67 to rotate the worm shaft of the adjacent pump. The rest of the pump mechanism is exactly as previously described, except that a manifold pipe 77 is connected to the inlet openings of each pump in the multiple installation and another manifold pipe 78 is connected to the outlet openings.

Although I have described three preferred embodiments of my invention in considerable detail, it will be understood that the description thereof is intended to be illustrative, rather than restrictive, as many details of the structure may be modified or changed without departing from the spirit or scope of the invention. Accordingly, I do not desire to be restricted to the exact construction described.

I claim:

1. A pump comprising a cylinder having inlet and outlet ports, a hardened sleeve fixed within said cylinder and provided with openings in registration with said cylinder ports, a piston mounted within said sleeve, said piston having a single port opening, the edges of said piston contiguous to its port opening being hardened, a splined shaft rigidly secured to said piston, means for rotating said shaft, a cam cylinder fixed to said piston and shaft, a circumferential cam groove in said cam cylinder, a gear case secured to the pump cylinder, and a cam roller fixed to said gear case, said cam roller being positioned in said groove to reciprocate said piston longitudinally of said pump cylinder as said piston is rotated by rotation of said shaft, whereby rotation of said shaft moves said piston port sequentially into and out of registration alternately with each of said cylinder ports, the interengagement of the hardened edges of said piston port and said sleeve openings being effective to cut or shear any solids caught therebetween as said piston port moves out of registration with said cylinder ports.

2. A pump comprising a cylinder having inlet and outlet ports, a piston mounted within said cylinder, said piston having a single port opening, a splined shaft rigidly secured to said piston, means for rotating said shaft, a cam cylinder fixed to said piston by said shaft, a circumferential cam groove in said cam cylinder, a gear case secured to the pump cylinder, and a cam roller fixed to said gear case, said cam roller being positioned in sa d groove to reciprocate said piston longitudinally of said pump cylinder as said piston is rotated by rotation of 5 6 said shaft, whereby rotation of said shaft moves said 2,265,758 Klosson Dec. 9, 1941 piston port sequentially into and out of registration 211- 2,291,601 Bancroft Aug. 4, 1942 ternately with each of said cylinder ports. 2,627,818 Davis Feb. 10, 1953 2,667,840 High Feb. 2, 1954 References Cited In the file of this patent 5 2 70 0 Peterson M 24, 1955 UNITED STATES PATENTS FOREIGN PATENTS 312,726 Johnston Feb. 24, 1885 84 Switzerland of1908 1,312,962 Dourte Aug. 12, 1919 363 977 m y 16, 1922 2,050,104 Lauchenauer Aug. 4, 1936 10 565,829 France Feb. 5, 1924

Images