US 3650481 A
The grinder pump includes an electric motor drive, cooperating cutter blade and grinder members one of which is secured to the motor shaft at an inlet for the grinder pump unit, an axial flow inducer impeller axially inwardly of and immediately adjacent to the cooperating cutter blade and grinder members, and a centrifugal pump means having an inlet directly connecting to and receiving the discharge from the axial flow inducer impeller, all of the driven members being controlled by and carried on the shaft of the electric motor.
Description (OCR text may contain errors)
United States Patent Conery et a1.
[ 51 Mar. 21, 1972  GRINDER PUMP  Inventors: William J. Conery; Donald A. Kaessen,
both of Ashland, Ohio 1  Assignee: Hydr-O-Matic Pump Company, Hayesyi LeQhiQ.  Filed: Apr. 1, 1971 211 App]. No.: 130,276
 U.S.Cl. ..24l/46.11, 241/257 G, 241/258  Int. Cl. ..B02c 18/40  Field ofSearch ..241/46 A, 46 B, 46.11,46.l7, 241/257 R, 257 G, 258, DIG. 32
 References Cited UNITED STATES PATENTS 2,714,045 7/1955 Simenson ..241/D1G. 32
2,853,249 9/1958 Wilder ..241/46.1l X 2,857,109 10/1958 Haeussler ....24l/46.1l 3,128,051 4/1964 Smith ..241/46.l1
Primary ExaminerGranville Y. Custer, Jr. Attorney-Oldham & Oldham  ABSTRACT The grinder pump includes an electric motor drive, cooperating cutter blade and grinder members one of which is secured to the motor shaft at an inlet for the grinder pump unit, an axial flow inducer impeller axially inwardly of and immediately adjacent to the cooperating cutter blade and grinder members, and a centrifugal pump means having an inlet directly connecting to and receiving the discharge from the axial flow inducer impeller, all of the driven members being controlled by and carried on the shaft of the electric motor.
11 Claims, 11 Drawing Figures PATENTEUMARZ] m2 SHEET 1 [1F 2 INVENTORS WILLIAM J. CON ERY BY DQNALD A. KAESSEN FIG.I
PATENTEDHARZI I972 SHEET 2 BF 2 FIG. IO
INVENTORS. WILLIAM J. CQNERY DONALD A. KAESSEN ATTORNEYS.
GRINDER PUMP The present invention, in general, relates to a grinder pump unit having improved characteristics for pumping liquids, and cutting up solids in the volume of liquid being processed.
BACKGROUND OF THE INVENTION Heretofore there have been various types of garbage grinders and other types of grinders wherein a driven rotatable cutter means is provided for breaking up solids and for forcing or moving a fluid or a liquid through the grinder unit. Some of these grinder units have been conventional garbage grinders or disposals as shown in US. Pat. No. 2,682,356, while other patented structures in the prior art have provided a double cutting or grinding action where after the material has passed through an initial inlet break-up and grinding or cutting zone, following grinding or cutting action is provided in the unit, as evidenced by the constructions shown in U.S. Pat. Nos. 2,853,249; 2,442,812; and 2,322,058. However, even in these multiple or double cutting units, it has been difficult to provide a grinder or disposer unit wherein substantially any solid material can be introduced into the device and be ground up into satisfactory small elements for flow through the grinder or disposal system, It furthermore has been customary in most instances for these grinder units to be located on vertical axes with some discharge means at the lower portion of the unit, and relatively small volumes of liquid are processed per minute.
In Wilder US. Pat. No. 2,853,249, the suggestion of having some type of pump impeller blades in the unit is proposed, but these blades are integral with the shearing or grinding member in the unit and a very inefficient pumping action is secured.
The general object of the present invention is to provide a novel and improved pumpgrinder means which includes a separate pump to aid in drawing pumped liquids through the grinder unit of the invention at a desirable fast volume flow rate.
A further object of the invention is to provide improved grinder and/or cutting actions in the grinder unit; and to provide an axial flow inducer impeller which cooperates with the initial grinding or cutting section of the unit for additional cutting action and a drawing or forcing of the pumped liquid axially in the unit, and a centrifugal pump connected to and receiving the discharge from the axial flow inducer impeller for pumping it out of the unit.
Another object of the invention is to provide an improved association between an inlet rotating cutter blade and an associated stationary grinder ring means having a plurality of cutting and/or grinding teeth provided thereon and wherein alternate teeth in the grinder ring are of different radial lengths to improve the cutting action and axial flow of a liquidsolid mixture through the apparatus of the invention.
Another object of the invention is to provide a grinder pump unit which is adapted to process large volumes of sewage or other materials such as liquids having solids therein and including rags, garbage and other materials and wherein the grinder pump unit will break up the solids into small pieces for flow through the apparatus of the invention for processing large volumes of sewage or other materials rapidly and efficiently.
Further objects of the invention are to provide an improved grinder ring tooth assembly for use in association with a driven cutter blade at the inlet of the unit and for improved volume flow of materials through the apparatus with a minimum of vibration to the rotating cutter blade; to provide sizable passages for fluids in the initial cutting or grinding zone of the unit; to provide an improved secondary cutting action in a grinder pump assembly by a disc type of an axial flow inducer impeller located axially immediately adjacent the stationary grinder ring for a secondary cutting action between the initial cutting members and the axial flow inducer impeller in the apparatus; to provide an axial flow inducer impeller wherein the teeth thereon extend the full axial length of the impeller whereby the impeller can be turned over, after removal from the apparatus, and be replaced to provide a double cutting life for the impeller before requiring sharpening; to provide improved cooperation between the teeth on an axial flow inducer impeller and associated inlet cutting or grinding means in the apparatus, to provide an odd number of cutting teeth on the inlet grinder ring and with alternate teeth being a different radial length; to provide a grinder pump with a submersible electric motor so that the complete unit can be submerged in the pumped liquid; to provide the submersible motor with two seals having an oil chamber between the seals to avoid contamination of the motor with the pump material; to provide an improved bearing in the seal oil chamber directly adjacent to the initial impeller seal in the unit; to provide a grinder pump that can be used to force material axially therethrough in any desired position and to provide a submersible grinder pump which can be used in a sewage or other refuse-liquid receiving sump to force large volumes of material into a discharge system connected to the sump.
Reference now is made to the associated drawings wherein:
FIG. 1 is a vertical section through the grinder pump embodying the principles of the invention and diagrammatically showing such grinder pump positioned in a sump;
FIG. 2 is a fragmentary inlet end elevation of the grinder pump of FIG. 1;
FIG. 3 is a vertical section of the grinder ring means of FIG.
FIG. 4 is a fragmentary elevation of the stationary grinder ring of the apparatus of FIG. 1;
FIG. 5 is an end elevation, partially in vertical section, of the stationary grinder ring of FIG. 4;
FIG. 6 is a fragmentary elevation of the cutter ring blade of the apparatus;
FIG. 7 is a side elevation of the cutter ring of FIG. 6;
FIG. 8 is a fragmentary plan of the axial flow inducer impeller of the apparatus;
FIG. 9 is an elevation of the impeller of FIG. 8 taken on line 9-9;
FIG. 10 is a vertical section through the pump impeller of the centrifugal pump in the grinder pump; and
FIG. 11 is a fragmentary plan view of a portion of the impeller of FIG. 10 taken on line ll-l1.
When referring to corresponding members shown in the drawings and referred to in the specification, corresponding numerals are used to facilitate comparison therebetween.
INVENTIVE SUBJECT MATTER In general, the present invention as one embodiment thereof, relates to a grinder pump unit adapted for forced flow of sewage or other material therethrough and wherein a housing and electric motor means is present and includes a shaft extending from the motor, the housing having an inlet provided therefor and cooperating cutter blade and grinder means members are positioned at the inlet for the unit with the cutter blade member being secured to the shaft, an axial flow inducer impeller is secured to the shaft axially inwardly immediately adjacent the cutter blade member, and a centrifugal pump means is provided within the housing and includes an impeller secured to the shaft. The pump has an inlet directly connecting to and receiving the discharge from the axial flow inducer impeller, and a discharge means is provided for the pump and connects thereto.
Reference now is particularly directed to the details of the structure shown in the drawings, and a grinder pump is indicated as a whole by the numeral 10. This grinder pump includes a housing indicated as a whole by the numeral 12 with a suitable electric motor 14 being provided in one portion of the housing 12 which is shown made from several axially abutting sections. The electric motor 14 has a shaft 16 which protrudes therefrom and extends substantially to an inlet 18 provided at one end of the housing 12. This inlet 18 is formed in an inlet ring 20 that is secured to a section 22 of the housing 12 as by cap screws 24 or the like. The inlet ring preferably has a pinrality of cutting or grinder teeth 26 formed therein and extending generally axially thereof.
The axially outer end of the motor shaft 16 has an inlet cutter blade member or rotor 28 secured thereto, and such cutter or grinder disc or member 28 has at least a pair of axially outwardly extending cutter blades 30 and 32 formed thereon or usually formed integrally therewith and terminating in axially directed outer edges 34 at the periphery of the disc as best shown in FIGS. 6 and 7 of the drawings. Any other suitable or conventional cutter or grinder means including smaller teeth 36 are provided on the axially outer face of the disc 28 for additional cutting, grinding or shredding action on materials being introduced into or flowing through the grinder pump of the invention.
The initial or primary grinding and/or cutting action is obtained in the grinder pump by cooperation of the disc 28 and the teeth thereon with a fixedly positioned grinder ring, means or member 38 that is of annular form and is suitably seated in a recess provided in the housing section 22 and secured thereto in any conventional manner. This grinder member 38 is of annular form and is shown in detail in FIGS. 4 and of the drawings which indicate that a plurality of grinder teeth 40 are provided at circumferentially spaced radially inner portions of the grinder member 38 and with, preferably, a circumferentially outwardly curved recess 41 being provided intermediate each pair of the grinder teeth 40. FIG. 4 of the drawings best shows, as a further feature of the invention, that an odd number of grinder teeth 40 are provided in the grinder ring 38 and with alternate ones of these teeth as indicated at 400 and 40b being of different radial length, as indicated by the different lengths of the lines 11-6 and a-d in FIG. 4. For this paired relationship of alternately longer and shorter teeth to form a ring with an off number of teeth therein, one pair of adjacent teeth have the same radial length and in this instance, the tooth 400 is shown to be of the same length as its adjacent tooth 40a and where the spacing of this tooth from the center of the ring is indicated by the line a-d, which is of the same length as the line a-c. Thus, by this feature of the invention, a relatively large pathway is provided by the recesses 41 in the grinder ring 38 whereby the material being pumped can rapidly flow in volume through the operating grinder and/or cutting zone or assembly formed by the cutter or grinder disc 28 in association with the grinder ring 38 that encompasses the grinder disc. The circumferentially spaced axially extending cutting edges of the grinder teeth 40 are immediately adjacent and parallel to the straight edges 34 on the axially extending cutter blades 30 and 32 on the cutter disc 28 for effective cutting and grinding action by driven rotation of the shaft 16.
As a further important feature in the grinder pump unit of the invention, an axial flow inducer impeller 42 is positioned immediately adjacent to the grinder disc 28 on the axially inner surface thereof and which impeller 42 is of generally disc shape. This axial flow inducer impeller has a plurality of blades or teeth 44 provided thereon which teeth 44 have an appreciably inclination, as shown in FIG. 9, to the longitudinal axis of the grinder pump and which teeth likewise extend some appreciable circumferential distance around the periphery of the impeller 42. In the present instance, only four of these teeth 44 are shown and they are circumferentially spaced from each other and with the ends of each of the teeth 44 terminating flush with an edge surface of the impeller as indicated at 44a and 44b of the drawings. This impeller 42 is suitably secured to the shaft 16 for drive thereby, and it should be noted that the axially outer edges 44a of the teeth 44 are positioned immediately adjacent and below the axially inner edges or ends of the individual teeth 40 provided on the grinder ring 38 whereby any elongate or fibrous members passing into the grinder pump have a secondary cutting or shredding action effected thereon by the relative rotation of the impeller 42 in relation to the grinder ring 38 and the teeth thereon.
Yet a further important feature of the invention is that a centrifugal pump is formed as a unit with the remaining portions of the apparatus and which unit includes an impeller 46 suitably secured to and carried by the motor shaft 16 for drive thereof as a unit with the grinder disc 28 and associated means. This impeller 46 is a portion ofa centrifugal pump 48 that forms an enclosure around the impeller 46 by a portion of the housing section 22 that forms a pumping chamber 50 around the periphery of the impeller 46. The impeller 46 may have any suitable circumferentially pumping vanes indicated at 52 provided on the face thereof adjacent to the inlet 53 for the pump 48. Such inlet 53 is directly axially associated with and positioned immediately adjacent the discharge face or surface of the impeller 42. The inlet is annular and is aligned with the axial flow of the pumped liquid provided by the axial flow inducer impeller 42. A conventional outlet 54 is formed in a portion of the housing means 12 and an outlet pipe 56 connects thereto for discharge of the pumped material.
By this combination of an initial cutting and grinding action on the pumped material, plus a secondary cutting action between the axial flow inducer impeller and the grinder ring teeth, an effective cutting and/or shredding action is provided on the solids in the pumped liquid, and by use of a centrifugal pump directly connected to and receiving the outlet from the axial flow inducer impeller 42 and associated means, a positive flow of pumped liquid and materials can be obtained through the grinder pump of the invention. At the same time, any solid materials initially present in this liquid can be cut or ground up to small particle form whereby rags and other fibrous materials can pass through the grinder pump and be effectively processed to be moved on in the liquid treatment system for further action on the pumped fluid.
As yet a further feature of the invention, it is preferred that a submersible type of an electric motor 14 be used in the grinder pump so that the grinder pump can be positioned in a known manner as shown diagrammatically in FIG. 1, in a sump 60. The grinder pump 10 can be positioned in such sump in any conventional manner as being supported on the bottom of the sump by suitable leg or bracket means, or the unit can be positioned on a vertically extending support means of a known type. In this instance, the inlet 18 faces downwardly of the sump but is spaced from the bottom thereof and the liquid in the sump can rise above the motor 14. Conventional controls would be provided for the motor to drive it upon predetermined depth of liquid received in the sump and for controlling motor drive until a predetermined lower liquid level is obtained in the sump.
For this electric motor 14 to be effectively used in the practice of the invention, it is important to separate the motor from the pumped material and thus in the present invention, a pair of axially spaced seal assemblies have been positioned in engagement with the motor shaft 16. These seal assemblies are indicated as a whole by the numbers 62 and 64. A separate housing section 66 is provided as a portion of the housing means 12 and is suitably attached thereto with the section 66 providing a chamber 68 between the seal 62 and 64. Thus, a suitable material, such as oil, can be received in the chamber 68 and this forms an isolation chamber between the electric motor and the pumped liquid. It also is necessary to provide a bearing 70 that is carried by a separate end plate 72 formed as a portion of the casing of the pump 48 and which has a tubular extension 72a extending therefrom in which the bearing 70 for the shaft is received to aid in positioning this shaft for efficient, maintenance free operation.
The seals 62 and 64 can be of any known mechanical type.
The provision of the axially spaced seals 62 and 64 with an oil chamber therebetween aids in the use of the invention with a submersible electric motor that can be adapted for upward pumping of liquid materials while grinding, shredding and cutting any solids present in such materials.
It should be noted that the axial flow inducer impeller 42 is of a flat disc shape and that the blades or teeth 44 formed thereon can be serviceable with rotation of the impeller in opposite directions. Thus, the impeller disc can be removed from the unit of the invention, be turned over and be replaced for further pumping action. This gives a double life on the impeller 42 without any sharpening action being provided or required, so as to reduce maintenance and operation costs of the unit of the invention.
The unit of the invention has provided a high rate or volume of forced flow of materials from the grinder pump and at the same time solids in such pumped liquid have been cut or ground to suitable form for passage through the apparatus of the invention. Thus, it is believed that the objects of the invention have been achieved.
While one complete embodiment of the invention has been disclosed herein, it will be appreciated that modification of this particular embodiment of the invention may be resorted to without departing from the scope of the invention as defined in the appended claims.
What is claimed is:
l. A grinder pump comprising an electric motor means including a shaft extending therefrom, an inlet being provided for said housing, cooperating cutter blade and grinder means members one of which is secured to said shaft at an inlet for the unit, an axial flow inducer impeller positioned axially inwardly of and immediately adjacent said cutter blade member, said impeller being secured to said shaft, and a centrifugal pump means including an impeller secured to said shaft, said pump having an inlet directly connecting to and receiving the discharge from said axial flow inducer impeller.
2. A grinder pump unit as in claim 1 where teeth are provided on said grinder means and some teeth are longer than others.
3. A grinder pump as in claim 1 where said grinder means has an odd number of teeth therein and every other one ofsaid teeth is radially shorter than the teeth adjacent thereto, except for one pair of adjacent teeth which are of the same length.
, 4. A grinder pump unit as in claim 1 where said axial flow inducer impeller has teeth thereon extending the axial length thereof and surfaces of said teeth cooperate with surfaces of said grinder teeth for additional cutting and/or grinding action.
5. A grinder pump unit comprising a housing and electric motor means, said electric motor including a shaft extending therefrom, an inlet being provided for said housing, an inlet cutter blade secured to said shaft, grinder ring means including grinder teeth carried by said housing and encompassing said inlet cutter blade, an axial flow inducer impeller positioned axially inwardly of and immediately adjacent said inlet cutter blade, said impeller being secured to said shaft, a centrifugal pump means within said housing and including an impeller secured to said shaft, said pump having an inlet directly connecting to and receiving the discharge from said axial flow inducer impeller, and a discharge means for said pump means connecting thereto.
6. A grinder pump unit as in claim 5 where some of said grinder teeth on said grinder ring means are radially longer than others, and where radially outwardly extending circular recesses are formed between said grinder teeth.
7. A grinder pump as in claim 5 where said grinder ring means has an odd number of teeth therein and every other one of said teeth is radially shorter than the teeth adjacent thereto, except for one pair of adjacent teeth which are of the same length.
8. A grinder pump unit as in claim 5 where said axial flow inducer impeller has teeth thereon extending the axial length thereof and flat end surfaces are formed on said teeth to cooperate with end surfaces of said grinder ring teeth for additional cutting and/or grinding action.
9. A grinder pump unit as in claim 1 where said motor is submersible.
10. A grinder pump unit as in claim 9 where said motor has two axially spaced seals with an oil chamber formed therein between said seals.
11. A grinder pump unit as in claim 1 where said axial flow inducer impeller, which is of disc shape, has teeth thereon extending the axial length thereof and end surfaces of said teeth are flat and said axial flow inducer impeller can be reversed for double use of said impeller without sharpening its teeth.