DIAPHRAGM PUMP APPARATUS

• US 3,814,548 A
• Filed: 08/05/1971
• Issued: 06/04/1974
• Est. Priority Date: 08/05/1971
• Status: Expired due to Term

• Current Assignee: Warren Rupp, Inc. (RELX PLC)
• Original Assignee: Warren E. Rupp
• Inventors: Rupp, Warren E.
• Primary Examiner(s): Freeh, William L.
• Assistant Examiner(s): Smith, Leonard
• Application Number:
  US05/169,292
• Time in Patent Office: 1,034 Days
• Field of Search: 417/395,398,402,63,326,470,471 92/13.8,98R,98D,99,100 91/443,446,357
• US Class Current: 417/395
• CPC Class Codes: F04B 43/073 the actuating fluid being controlled by at least one valve

Abstract

Pump apparatus having a reciprocable diaphragm for delivering a highly accurate amount of pumped fluid per diaphragm pumping stroke. The amount of fluid pumped over a time interval may be accurately varied by adjusting the frequency or duration of the diaphragm stroke, or by adjusting the length of the stroke or by both measures. The diaphragm of the apparatus is moved in its pumping stroke by air applied to the rear side of the diaphragm, or the side opposite the front side contacted by the pumped fluid. Air pressure is always maintained on the rear side of the diaphragm to insure that the unsupported portion of the diaphragm between its outer supported edge portion and its central supported portion is at all times bowed toward the front side of the diaphragm; this prevents random positioning of this portion of the diaphragm in concave and convex positions during its stroking, and substantially increases the accuracy of the amount of fluid pumped per stroke. The apparatus includes means for varying the length of the stroke from outside of the apparatus. Also disclosed are solenoid actuated valve means for controlling the supply of air to move the diaphragm in its pumping stroke and timer means for controlling the solenoid so that the frequency or duration of the pumping stroke of the diaphragm can be varied as desired.

Claims

1. Diaphragm pump apparatus comprising a first chamber;

a second chamber into which fluid to be pumped is drawn and from which it is discharged;

a flexible diaphragm separating said chambers in fluid tight relation;

means for moving said diaphragm in a pumping stroke towards said second chamber; and

means for moving said diaphragm in a suction stroke in a direction opposite to said pumping stroke, said means comprising a third chamber, a cylinder communicating with said third chamber, a piston in said cylinder and connected to said diaphragm so said piston can move in said cylinder to move said diaphragm on its suction stroke, the volume of said third chamber being substantially larger than the volume of said cylinder to provide a springing effect, and means for maintaining gas at a superatmospheric pressure in said third chamber, whereby when the force on said diaphragm due to fluid pressure in said first chamber is lower than the force on said piston due to fluid pressure in said third chamber said piston will retract said diaphragm.

2. Diaphragm pump apparatus comprising a first chamber;

a second chamber into which fluid to be pumped is drawn and from which it is discharged;

a flexible diaphragm separating said chambers in fluid-tight relation and having an unsupported portion extending around said diaphragm;

means for reciprocating said diaphragm so that it moves in a pumping stroke toward said second chamber and in a suction stroke toward said first chamber, said reciprocating means including means for supplying fluid under pressure into said first chamber to exert force directly on said diaphragm to move said diaphragm in its pumping stroke toward said second chamber and fluid operated means for moving said diaphragm in its suction stroke toward said first chamber and comprising a third chamber, a cyLinder communicating with said third chamber, a piston in said cylinder and connected to said diaphragm so said piston can move in said cylinder to move said diaphragm in its suction stroke, the volume of said third chamber being substantially larger than the volume of said cylinder to provide a springing effect, and means for supplying gas at a superatmospheric pressure in said third chamber, whereby when the force on said diaphragm due to fluid pressure in said first chamber is lower than the force on said piston due to gas pressure in said third chamber said piston will move said diaphragm in its suction stroke; and

means for maintaining at all times in said first chamber fluid at a superatmospheric pressure greater than the pressure of fluid in said second chamber and sufficient to keep said unsupported portion of said diaphragm at all times bowed towards said second chamber.

3. Diaphragm pump apparatus comprising a first chamber a second chamber into which fluid to be pumped is drawn and from which it is discharged;

a flexible diaphragm separating said chambers in fluid tight relation;

means for moving said diaphragm in a pumping stroke towards said second chamber; and

means for moving said diaphragm in a suction stroke in a direction opposite to said pumping stroke, said means comprising a third chamber, a cylinder communicating with said third chamber, a piston in said cylinder and connected to said diaphragm so said piston can move in said cylinder to move said diaphragm on its suction stroke, the volume of said third chamber being substantially larger than the volume of said cylinder to provide a springing effect, and means for supplying gas at a superatmospheric pressure in said third chamber, whereby when the force on said diaphragm due to fluid pressure in said first chamber is lower than the force on said piston due to fluid pressure in said third chamber said piston will retract said diaphragm.

4. Diaphragm apparatus comprising a first chamber;

a second chamber;

a flexible diaphragm separating said first chamber from said second chamber and having an unsupported portion extending around said diaphragm;

means for reciprocating said diaphragm so that in a forward stroke it moves toward said first chamber and on a reverse stroke it moves toward said second chamber, said reciprocating means including means for supplying fluid under pressure into said first chamber to exert force directly on said diaphragm to move said diaphragm in its reverse stroke toward said second chamber, said reciprocating means also including means operable by fluid pressure for moving said diaphragm in its forward stroke towards said first chamber, said means comprising a third chamber, a cylinder communicating with third chamber, a piston in said cylinder and connected to said diaphragm so said piston can move in said cylinder to move said diaphragm on its forward stroke, the volume of said third chamber being substantially larger than the volume of said cylinder to provide a springing effect, and means for maintaining gas at a superatmospheric pressure in said third chamber, whereby when the force on said diaphragm due to fluid pressure in said first chamber is lower than the force on said piston due to gas pressure in said third chamber, said piston will move said diaphragm in its forward stroke; and

means for maintaining at all times in said first chamber fluid at a pressure greater than the fluid pressure in said second chamber and sufficient to bow said unsupported portion of said diaphragm at all times toward said second chamber.

5. The apparatus of claim 4 comprising means for adjusting the length of stroke of said diaphragm externally of said third chamber.

6. Diaphragm pump apparatus comprising a first chamber;

a second chamber into which fluid to be pumped is drawn and from which it is discharged;

a flexible diaphragm separating said chambers in fluid-tight relation and having a flexible unsupported portion extending around said diaphragm;

means for reciprocating saiD diaphragm so that it moves in a pumping stroke toward said second chamber and in a suction stroke toward said first chamber, said reciprocating means including means for supplying fluid under superatmospheric pressure into said first chamber to exert force directly on said diaphragm to move said diaphragm in a pumping stroke toward said second chamber and means for moving said diaphragm in a suction stroke towards said first chamber; and

means for maintaining at all times in said first chamber said fluid at a superatmospheric pressure greater than the pressure of fluid in said second chamber and sufficient to keep said unsupported portion of said diaphragm at all times bowed towards said second chamber including during its pumping and suction strokes;

said means for moving said diaphragm toward said first chamber exerting sufficient force to overcome the force exerted on the diaphragm by the superatmospheric pressure of fluid in said first chamber that keeps the unsupported portion of the diaphragm bowed toward the second chamber while permitting said unsupported portion of said diaphragm to be at all times bowed toward said second chamber.

7. The apparatus of claim 6 in which said reciprocating means includes piston-cylinder means operable by fluid under pressure applied to said piston to move said diaphragm in said suction stroke.

8. The apparatus of claim 6 in which said diaphragm is clamped at its outer edge and is connected at its central portion to means included in said reciprocating means for moving said diaphragm in said suction stroke, and has said unsupported portion between said outer edge and said connected means, and in which said unsupported portion is at all times bowed toward said second chamber by said fluid under superatmospheric pressure in said first chamber.

9. The apparatus of claim 6 in which said means for moving said diaphragm on its suction stroke comprises fluid operated means.

10. The apparatus of claim 6 in which said means for moving said diaphragm in its suction stroke is mechanical means.

11. The apparatus of claim 6 comprising means for adjusting the length of the stroke of said diaphragm from outside of said apparatus.

12. The apparatus of claim 6 in which said means for introducing fluid into said first chamber comprises a fluid valve for controlling the supply of fluid to said first chamber, a solenoid for controlling said valve, and presettable timer means for controlling the energizing of said solenoid to provide a predetermined duration of stroke of said diaphragm.

13. The apparatus of claim 6 comprising fluid valve means for controlling the supply of fluid to said first chamber, and adjustable timer means for controlling the operation of said valve means to provide a predetermined time interval during which a suction stroke and a pumping stroke occur.

14. The pump apparatus of claim 10 in which said mechanical means is spring means operating between a support connected to said diaphragm and a support connected to one of said chambers to move said diaphragm on its suction stroke.

15. The apparatus of claim 10 in which said mechanical means is enclosed in said first chamber into which fluid is supplied to move said diaphragm on its pumping stroke.