PUMP UNLOADER VALVE AND ENGINE THROTTLE SYSTEM

• US 20110142685A1
• Filed: 12/16/2009
• Published: 06/16/2011
• Est. Priority Date: 12/16/2009
• Status: Abandoned Application

• Current Assignee: Briggs & Stratton Corporation
• Original Assignee: Briggs & Stratton Corporation
• Inventors: Gilpatrick, Richard J.
• Application Number:
  US12/639,864
• Publication Number:
  US 20110142685A1
• Time in Patent Office: Days
• US Class Current: 417/34
• CPC Class Codes: F04B 49/20 by changing the driving speed

Abstract

A pressure washer system includes an engine, a water pump, a sprayer, an unloader, and a link. The engine has a throttle system designed to control the speed of the engine. The water pump includes an inlet, a pumping mechanism, and an outlet. The pumping mechanism is designed to be driven by the engine. The sprayer is attached to the outlet of the water pump. The unloader is designed to direct water toward the inlet of the water pump when the unloader is in a first configuration, and to direct water toward the sprayer when the unloader is in a second configuration. Water pressure generated when the sprayer is not actuated moves the unloader to the first configuration. The link connects the unloader and the throttle system of the engine, where the link is designed to adjust the throttle system to a first engine speed when the unloader is in the first configuration, and to adjust the throttle system to a second engine speed when the unloader is in the second configuration.

Claims

1. A pressure washer system, comprising:

an engine having a throttle system configured to control the speed of the engine;

a water pump comprising an inlet, a pumping mechanism, and an outlet, the pumping mechanism configured to be driven by the engine;

a sprayer coupled to the outlet of the water pump;

an unloader configured to direct water toward the inlet of the water pump when the unloader is in a first configuration, and to direct water toward the sprayer when the unloader is in a second configuration, wherein water pressure generated when the sprayer is not actuated moves the unloader to the first configuration; and

a link coupling the unloader and the throttle system of the engine, wherein the link is configured to adjust the throttle system to a first engine speed when the unloader is in the first configuration, and to adjust the throttle system to a second engine speed when the unloader is in the second configuration.

2. The pressure washer system of claim 1, wherein the first engine speed is an idle speed and the second engine speed is greater than the idle speed.

3. The pressure washer system of claim 2, wherein the link comprises a Bowden cable having an inner wire and an outer sheath.

4. The pressure washer system of claim 3, wherein the unloader comprises a valve plug and the inner wire of the Bowden cable is coupled to the valve plug.

5. The pressure washer system of claim 4, wherein the valve plug is coupled to a valve stem configured to produce a translation of the valve plug of a predetermined distance when the unloader changes from the first configuration to the second configuration, and wherein the predetermined distance is at least a quarter of an inch.

6. A system for pressurizing a fluid, comprising:

an engine having a throttle system configured to control the speed of the engine;

a pump comprising an inlet, a pumping mechanism, and an outlet, the pumping mechanism driven by the engine;

an unloader coupled to the pump and configured to open a bypass conduit directing fluid from the outlet of the pump to the inlet of the pump when the unloader is in a first configuration, and to close the bypass conduit when the unloader is in a second configuration; and

a link coupling the unloader to the throttle system of the engine, wherein the link is configured to adjust the throttle system to a first engine speed when the unloader is in the first configuration, and to adjust the throttle system to a second engine speed when the unloader is in the second configuration.

7. The system of claim 6, wherein the first engine speed is an idle speed and the second engine speed is greater than the idle speed.

8. The system of claim 7, wherein the unloader comprises a movable valve plug, and wherein the link is coupled to the valve plug such that the link adjusts the throttle system in response to movement of the valve plug.

9. The system of claim 8, wherein the link comprises a Bowden cable fastened to a lower spring support coupled to a spring of the unloader configured to bias the valve plug.

10. The system of claim 9, wherein the Bowden cable is also coupled to a governor spring of the engine, and wherein the governor spring is coupled to a throttle plate, whereby movement of the valve plug changes tension in the governor spring, which adjusts the throttle plate.

11. The system of claim 10, wherein the pumping mechanism comprises at least one of a piston and an impeller.

12. The system of claim 10, wherein the pump is at least one of an axial cam water pump and a triplex water pump.

13. An unloader system for use with a pump, comprising:

a housing configured to be fastened to an outlet of the pump;

a valve plug having a first position and a second position relative to the housing;

a spring biasing the valve plug toward the second position; and

a link coupled to the valve plug, wherein the link is configured to communicate movement of the valve plug to control the pump.

14. The unloader system of claim 13, wherein the valve plug includes an extension configured to produce a translation of the valve plug of a predetermined distance when the valve plug moves from the first position to the second position.

15. The unloader system of claim 14, wherein the predetermined distance is at least a quarter of an inch.

16. The unloader system of claim 15, wherein in the link includes a Bowden cable comprising an inner wire and an outer sheath, the inner wire translatable relative to the outer sheath.

17. The unloader system of claim 16, further comprising an adjustment mechanism including a threaded shaft extending through a treaded aperture in the housing and positioned in series with the spring such that rotating the threaded shaft relative to the housing alters tension in the spring.

18. The unloader system of claim 17, wherein the inner wire of the Bowden cable extends into the housing of the unloader and is coupled to the valve plug.

19. The unloader system of claim 18, wherein the outer sheath of the Bowden cable is fastened to at least one of a nut and a barrel adjuster.

20. The unloader system of claim 19, wherein the housing is configured to be fastened to the outlet of the pump via a male threaded portion on an exterior of the housing that is configured to be coupled to a port in a discharge manifold of the outlet of the pump.