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US3779669A Expired / Lapsed US ⏱️ 0.0 years remaining

Pump spray unit

Assignee: Wooster Brush Co
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Filing: 1972-05-22
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Granted: 1973-12-18
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Expires: 1992-05-22
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Abstract

Abstract Pump spray unit has a lost-motion connection between the pump diaphragm and pump piston which ensures full retraction of the diaphragm during retraction of the piston for obtaining the desired amount of working fluid within the working fluid chamber prior to the pumping stroke of the piston and diaphragm. An adjustable relief valve is also provided for relieving the excess working fluid pressure which is created during standby operation of the pump to the back side of the piston which causes the piston to move forward out of engagement with its drive cam thereby retaining the piston and diaphragm against movement during standby to minimize wear and power consumption during standby. The high pressure acting on the back side of the piston is bled off through a restricted orifice, and when pumping is resumed the pressure quickly drops to a level at which the piston is again urged by a return spring into engagement with the drive cam for reciprocation thereby.

Inventors

  • 👤 H Sommer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 19:47
CPC Classifications
F; F04; F04B; F04B43/00; F04B43/02; F04B43/06; F04B43/067; B; B05; B05B; B05B9/00; B05B9/03; B05B9/04; B05B9/0403; B05B9/0409

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 223 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore to force a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means providing a lost-motion connection between said piston and diaphragm to insure flexing of said diaphragm in a direction causing a reduction in the size of said one chamber during retraction of said piston, said means providing a lost-motion connection between said piston and diaphragm comprising a rod having one end connected to said diaphragm, a stepped recess in said piston into which the other end of said rod extends, said other end of said rod having a head thereon extending inwardly beyond the step in said recess, and a washer engaging said step for contacting said head during retraction of said piston to mechanically retract said diaphragm with said piston in the event that the partial vacuum which is created during retraction of said piston is not effective in causing said diaphragm to flex as aforesaid.
Claim 2
Dependent Claim 223 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore to force a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means providing a lost-motion connection between said piston and diaphragm to insure flexing of said diaphragm in a direction causing a reduction in the size of said one chamber during retraction of said piston, said means providing a lost-motion connection between said piston and diaphragm comprising a rod having one end connected to said diaphragm, a stepped recess in said piston into which the other end of said rod extends, said other end of said rod having a head thereon extending inwardly beyond the step in said recess, and a washer engaging said step for contacting said head during retraction of said piston to mechanically retract said diaphragm with said piston in the event that the partial vacuum which is created during retraction of said piston is not effective in causing said diaphragm to flex as aforesaid.
Claim 3
Dependent Claim 17 words
The pump of claim 1 further comprising a spring urging said washer into engagement with said step.
Claim 4
Dependent Claim 23 words
The pump of claim 2 wherein said spring is contained within said bore interposed between said washer and another washer in said bore.
Claim 5
Dependent Claim 70 words
The pump of claim 1 wherein the connection between said one end of said rod and said diaphragm consists of a pair of washers on opposite sides of said diaphragm, said one end of said rod extending through aligned openings in said washers and diaphragm, and a pair of nuts threadedly engaging said rod on opposite sides of said washers which are tightened for clamping said diaphragm between said washers.
Claim 6
Dependent Claim 29 words
The pump of claim 4 wherein the wall of said other chamber is relieved to avoid contact by said diaphragm during flexing of said diaphragm in the pumping direction.
Claim 7
Dependent Claim 170 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore which forces a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means for disconnecting said piston from said drive means when the pressure within said one chamber reaches a predetermined high level during standby operation of said pump to cause said piston and diaphragm to remain stationary during such standby operation, said drive means comprising a drive cam, said piston having a rod projecting from the outer end thereof, and a spring engaging the inner end of said piston for urging said rod into engagement with said drive cam during normal operation of said pump.
Claim 8
Dependent Claim 170 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore which forces a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means for disconnecting said piston from said drive means when the pressure within said one chamber reaches a predetermined high level during standby operation of said pump to cause said piston and diaphragm to remain stationary during such standby operation, said drive means comprising a drive cam, said piston having a rod projecting from the outer end thereof, and a spring engaging the inner end of said piston for urging said rod into engagement with said drive cam during normal operation of said pump.
Claim 9
Dependent Claim 158 words
The pump of claim 6 wherein said means for disconnecting said piston from said drive means comprises passage means providing communication bEtween opposite ends of said bore on opposite sides of said piston, and pressure relief valve means contained within said passage means which is opened in response to the pump pressure reaching such predetermined high level to prevent increased pressure build up within said pump, such high fluid pressure which is relieved by said pressure relief valve means being directed to the outer end of said bore by said passage means whereat such high fluid pressure acts on the back side of said piston which has an effective area sufficiently larger than the effective area of the front side of said piston that when such predetermined high pressure is reached, said rod is moved out of engagement with said drive cam thereby causing said piston and diaphragm to remain stationary during continued rotation of said drive cam.
Claim 10
Dependent Claim 29 words
The pump of claim 7 further comprising a restricted orifice for bleeding off the high pressure acting on the back side of said piston when normal pumping is resumed.
Claim 11
Dependent Claim 33 words
The pump of claim 8 wherein said restricted orifice comprises an adjustable check valve disposed in a further passage communicating said outer end of said bore with a reservoir containing such working fluid.
Claim 12
Dependent Claim 83 words
The pump of claim 7 wherein said pressure relief valve means comprises a ball valve contained in said passage providing communication between opposite ends of said bore, a seat in said passage for said ball valve, and spring means urging said ball valve into engagement with said seat, and an adjusting screw threadedly received in said passage for varying the pressure of said spring means acting on said ball valve, said adjusting screw having a central passage therethrough for such high pressure fluid.
Claim 13
Dependent Claim 34 words
The pump of claim 10 further comprising a pressure plate in said passage interposed between said spring means and ball valve, said pressure plate having flats thereon permitting fluid to bypass said pressure plate.
Claim 14
Dependent Claim 163 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore to force a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, means providing a lost-motion connection between said piston and diaphragm to insure flexing of said diaphragm in a direction causing a reduction in the size of said one chamber during retraction of said piston, and means for disconnecting said piston from said drive means when the pressure within said one chamber reaches a predetermined high level during standby operation of said pump to cause said piston and diaphragm to remain stationary during such standby operation of said pump.
Claim 15
Dependent Claim 163 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore to force a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, means providing a lost-motion connection between said piston and diaphragm to insure flexing of said diaphragm in a direction causing a reduction in the size of said one chamber during retraction of said piston, and means for disconnecting said piston from said drive means when the pressure within said one chamber reaches a predetermined high level during standby operation of said pump to cause said piston and diaphragm to remain stationary during such standby operation of said pump.
Claim 16
Dependent Claim 134 words
pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore which forces a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means for disconnecting said piston from said drive means in response to the pressure within said one chamber reaching a predetermined high level during standby operation of said pump to cause said piston and diaphragm to remain stationary during such standby operation while said drive means continues to operate.
Claim 17
Dependent Claim 134 words
pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for reciprocating said piston within said bore which forces a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means for disconnecting said piston from said drive means in response to the pressure within said one chamber reaching a predetermined high level during standby operation of said pump to cause said piston and diaphragm to remain stationary during such standby operation while said drive means continues to operate.
Claim 18
Dependent Claim 204 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for rEciprocating said piston within said bore to force a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means providing a lost-motion connection between said piston and diaphragm to insure flexing of said diaphragm in a direction causing a reduction in the size of said one chamber during retraction of said piston, said lost-motion connection including means permitting freedom of movement of said piston relative to said diaphragm during the initial movement of said piston from the fully extended position toward the fully retracted position, and means for positively retracting said diaphragm with said piston as said piston approaches the fully retracted position to assure such flexing of said diaphragm in the event said diaphragm does not flex in the desired direction as aforesaid during the initial movement of said piston toward the fully retracted position.
Claim 19
Dependent Claim 204 words
A pump comprising a housing, a cavity within said housing, a flexible diaphragm dividing said cavity into two separate chambers, a bore communicating with one of said chambers, a piston contained within said bore, drive means for rEciprocating said piston within said bore to force a working fluid into and out of said one chamber for flexing said diaphragm in opposite directions thereby respectively decreasing and increasing the volume of the other of said chambers for pumping fluid into and out of said other chamber, and means providing a lost-motion connection between said piston and diaphragm to insure flexing of said diaphragm in a direction causing a reduction in the size of said one chamber during retraction of said piston, said lost-motion connection including means permitting freedom of movement of said piston relative to said diaphragm during the initial movement of said piston from the fully extended position toward the fully retracted position, and means for positively retracting said diaphragm with said piston as said piston approaches the fully retracted position to assure such flexing of said diaphragm in the event said diaphragm does not flex in the desired direction as aforesaid during the initial movement of said piston toward the fully retracted position.

References Cited (Backward Citations)

GB305235A Cited
US1707508A Cited
US2912935A Cited
US2807215A Cited
US2936712A Cited
US3277795A Cited
US3612727A Cited
US3695648A Cited
US3680981A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-12-17 1977-06-18 1977-12-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-12-17 1981-06-18 1981-12-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-12-17 1985-06-18 1985-12-18 $7700.00 Window Closed / Lapsed

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