Vacuum source and float valve for a self-priming pump

• US 8,246,316 B2
• Filed: 09/13/2010
• Issued: 08/21/2012
• Est. Priority Date: 03/22/1999
• Status: Expired due to Term

• Current Assignee: David Muhs
• Original Assignee: David Muhs
• Inventors: Muhs, David
• Primary Examiner(s): Freay, Charles
• Application Number:
  US12/881,064
• Publication Number:
  US 20110008183A1
• Time in Patent Office: 708 Days
• Field of Search: 417/68, 417/199.2, 417/200
• US Class Current: 417/68
• CPC Class Codes: B01D 21/0012 Settling tanks making use of filters, e.g. by floating layers of particulate material
• CPC Class Codes: B01D 21/0018 provided with a pump mounted in or on a settling tank
• CPC Class Codes: B01D 21/0039 Settling tanks provided with contact surfaces, e.g. baffles, particles
• CPC Class Codes: B01D 21/0042 Baffles or guide plates
• CPC Class Codes: B60P 3/225 Adaptations for pumps or valves
• CPC Class Codes: E03F 1/006 Pneumatic sewage disposal systems; accessories specially adapted therefore
• CPC Class Codes: F04C 11/005 of dissimilar working principle
• CPC Class Codes: F04C 19/001 General arrangements, plants, flowsheets
• CPC Class Codes: F04C 29/0092 Removing solid or liquid contaminants from the gas under pumping, e.g. by filtering or deposition; Purging; Scrubbing; Cleaning
• CPC Class Codes: F04D 13/02 Units comprising pumps and their driving means
• CPC Class Codes: F04D 29/2288 for comminuting, mixing or separating
• CPC Class Codes: F04D 29/708 specially for liquid pumps
• CPC Class Codes: F04D 7/04 the fluids being viscous or non-homogenous
• CPC Class Codes: F04D 7/045 with means for comminuting, mixing stirring or otherwise treating
• CPC Class Codes: F04D 9/041 the priming pump having evacuating action F04D9/043 and F04D9/06 take precedence
• CPC Class Codes: F04D 9/042 and means for rendering its in operative
• CPC Class Codes: Y10T 137/6416 With heating or cooling of the system
• CPC Class Codes: Y10T 137/86043 Reserve or surge receiver

Abstract

A self priming pump system that includes a motor coupled to a centrifugal pump. A separator having a reservoir is provided for storing a limited amount of pumped fluid in advance of the centrifugal pump. A vacuum source provides a vacuum suction to the reservoir to draw pumped fluid into the reservoir to prime the pump. A float may be provided, wherein when the fluid level in the reservoir reaches a desired level, the float opens a float valve to let air into the reservoir to maintain the desired level. The float valve may have a capacity that is greater than or equal to the pumping capacity of the vacuum pump, or at least large enough to make up for a difference between the pumping capacity of the vacuum pump and an amount of fluid that can be pumped by the centrifugal pump from the reservoir.

Claims

1. A pump for pumping a fluid, the pump comprising:

a motor;

a centrifugal pump having a main inlet and a main outlet, the centrifugal pump having an impeller that is driven by the motor;

a reservoir having an inlet fluidly coupled to the main inlet of the centrifugal pump;

a vacuum pump fluidly coupled to the reservoir for creating a reduced pressure in the reservoir to help draw fluid through the inlet of the reservoir, the vacuum pump having a pumping capacity;

a float positioned in the reservoir for detecting a fluid level in the reservoir, wherein when the fluid level in the reservoir reaches a desired level, the float opens a float valve to let air into the reservoir to maintain the desired level; and

wherein, when the float valve is in a fully open position, the float valve has a size/capacity that is greater than or equal to the pumping capacity of the vacuum pump.

2. The pump of claim 1, wherein the float valve is a one-way valve that lets air into the reservoir but does not let fluid out of the reservoir.

3. The pump of claim 1, wherein the vacuum pump is also driven by the motor.

4. The pump of claim 1, wherein the vacuum pump is a liquid ring vacuum pump.

5. The pump of claim 1, wherein the vacuum pump includes an inlet port and the reservoir includes an outlet port, and wherein the inlet port of the vacuum pump is in fluid communication with the outlet port of the reservoir.

6. The pump of claim 5, further comprising a valve situated between the inlet port of the vacuum pump and the outlet port of the reservoir, wherein under negative head pressures, the valve fluidly connects the outlet port of the reservoir to the inlet port of the vacuum pump, and under positive head pressures, the valve fluidly connects the inlet port of the vacuum pump to atmosphere.

7. A pump for pumping a fluid, the pump comprising:

a motor;

a centrifugal pump having a main inlet and a main outlet, the centrifugal pump having an impeller that is driven by the motor;

a separator having an inlet and an outlet, wherein the outlet of the separator is fluidly coupled to the main inlet of the centrifugal pump;

a vacuum pump fluidly coupled to the separator for creating a reduced pressure in the separator to help draw fluid through the inlet of the separator, the vacuum pump having a pumping capacity;

a float positioned in the separator for detecting a fluid level in the separator, wherein when the fluid level in the separator reaches a desired level, the float opens a float valve to let air into the separator to maintain the desired level; and

wherein, when the float valve is in a fully open position, the float valve has a size/capacity that is less than the pumping capacity of the vacuum pump, but large enough to make up for a difference between the pumping capacity of the vacuum pump and an amount of fluid that can be pumped by the centrifugal pump from the separator under all expected head pressures.

8. The pump of claim 7, wherein the float valve is a one-way valve that lets air into the separator but does not let fluid out of the separator.

9. The pump of claim 7, wherein the vacuum pump is also driven by the motor.

10. The pump of claim 7, wherein the vacuum pump is a liquid ring vacuum pump.

11. The pump of claim 7, wherein the vacuum pump includes an inlet port and the separator includes an outlet port, and wherein the inlet port of the vacuum pump is in fluid communication with the outlet port of the separator.

12. The pump of claim 11, further comprising a valve situated between the inlet port of the vacuum pump and the outlet port of the separator, wherein under negative head pressures, the valve fluidly connects the outlet port of the separator to the inlet port of the vacuum pump, and under positive head pressures, the valve fluidly connects the inlet port of the vacuum pump to atmosphere.