IP Library › Granted Patent US 12,326,153
Granted Patent B2
US 12,326,153 · App. 18/386,313 · Granted Jun 10, 2025

Self cleaning cutter, cutting assembly, and pump

Inventor: Donald M. Pohler (North Chili, NY)
Assignee: Liberty Pumps, Inc.
F04D29/2288
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Quick Facts
Patent No.
US 12,326,153
App. No.
18/386,313
Granted
Jun 10, 2025
Kind
B2
Abstract

A rotatable cutter, which may be used in a cutting assembly and in a grinder pump, is provided comprising at least a first cutting blade and a second cutting blade. Each of the first and the second cutting blades include a central region and a distal region. A protruding nub extends axially outwardly from the distal region of at least one of the first and second cutting blades. The rotatable cutter is engageable with a rotating drive shaft, which may also be engaged with an impeller of the pump.

Claims (23)

1. A cutting assembly comprising:

a) a rotatable drive shaft;

b) a rotatable cutter engaged with the rotatable drive shaft and comprised of at least a first cutting blade and a second cutting blade, each of the first and the second cutting blades including a planar inner surface coplanar with each other, a central region and a distal region, the rotatable cutter further comprised of a single protruding nub extending axially outwardly from the distal region of one of the first and second cutting blades and including a radially outermost edge terminating short of the distal end of that one of the first and second cutting blades; and

c) a plate cutter comprised of an outer cutter surface contiguous with the planar inner surfaces of the blades of the rotatable cutter.

2. The cutting assembly of claim 1 , wherein the single protruding nub of the rotatable cutter is of a cylindrical shape.

3. The rotatable cutter of claim 1 , wherein the single protruding nub of the rotatable cutter is of an oblong shape.

4. The rotatable cutter of claim 1 , wherein the single protruding nub of the rotatable cutter is of a curvilinear shape.

5. A grinder pump comprising a pump volute enclosing a pump impeller, and a cutting assembly for size reduction of solids in a liquid to be pumped, the cutting assembly comprising:

a) a rotatable drive shaft;

b) a rotatable cutter engaged with the rotatable drive shaft and comprised of at least a first cutting blade and a second cutting blade, each of the first and the second cutting blades including a planar inner surface coplanar with each other, a central region and a distal region, the rotatable cutter further comprised of a single protruding nub extending axially outwardly from the distal region of one of the first and second cutting blades and including a radially outermost edge terminating short of the distal end of that one of the first and second cutting blades; and

c) a plate cutter comprised of an outer cutter surface contiguous with the planar inner surfaces of the blades of the rotatable cutter.

6. The grinder pump of claim 5 , wherein the single protruding nub of the rotatable cutter is of a cylindrical shape.

7. The grinder pump of claim 5 , wherein the single protruding nub of the rotatable cutter is of an oblong shape.

8. The grinder pump of claim 5 , wherein the single protruding nub of the rotatable cutter is of a curvilinear shape.

9. A rotatable cutter engageable with a rotating drive shaft and comprised of:

a) a first cutting blade and a second cutting blade, each of the first and the second cutting blades comprising a distal region, and each of the first and the second cutting blades extending radially outwardly from an axis of rotation of the rotating drive shaft to a distal end;

b) a single protruding nub extending axially outwardly from the distal region of one of the first and second cutting blades and including a radially outermost edge terminating short of the distal end of that one of the first and second cutting blades.

10. The rotatable cutter of claim 9 , wherein the single protruding nub is of a cylindrical shape.

11. The rotatable cutter of claim 9 , wherein the single protruding nub is of an oblong shape.

12. The rotatable cutter of claim 11 , wherein the single protruding nub extends radially outwardly with respect to a central axis of rotation of the cutter.

13. The rotatable cutter of claim 11 , wherein the single protruding nub extends circumferentially with respect to a central axis of rotation of the cutter.

14. The rotatable cutter of claim 9 , wherein the single protruding nub is of a curvilinear shape.

15. The rotatable cutter of claim 14 , wherein curvilinear shape of the single protruding nub corresponds to the shape of a forward edge of the first cutting blade.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 16, 2024
From: POHLER, DONALD M.
To: LIBERTY PUMPS, INC.
Reel/Frame 066139/0165 →
Continuity (1)
Related Publication 20250146505A1 · May 8, 2025
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