US2079406A

US2079406A - Oil trap for vacuum pumps

Info

Publication number: US2079406A
Application number: US744118A
Authority: US
Inventors: Gordon W Harry
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1934-09-15
Filing date: 1934-09-15
Publication date: 1937-05-04
Anticipated expiration: 1954-05-04

Description

May 4, 937. G, W, HARRY 2,079,406

OIL TRAP FOR VACUUM PUMPS Filedsept. 15, 1954 sheets-sheet 1 llmmn WINDSHELD CLEANER .v

' gmc/Wto@ jdaaf? 941622?? G. w. HARRY v 2,079,406

OIL TRAP FOR VACUUM PUMPS Filed Sept. l5, 1934 2 Sheets-Shea?l 2 HANIFBLD l wmos Ln cuan W @Ww Fatentee May e? E53? atar .erica 03H.. TRAP FR VACUUM IPS Gordon W. Harry, Fiint, Mich., assigner to Generai Motors Coii'poration,l Detroit, Mich., a corporation of Delaware appiication september i5, 1934, aerial No. tiene `1i) Claims.

This invention relates to pumps and particularly to a pump operable by the engine of a motor vehicle to withdraw air from the motor of a windshield cleaner. Pumps of this kind are fred quently of the booster type, the pump chamber beingin the path of air iiow from. the windshield cleaner to the engine manifold whereby the manifoldsuction may normally operate, unassisted by the vacuum pump, 'to evacuate the windshield cleaner motor, but in the event of insuiiicient engine suction the normal operation may be supplemented by the operation of the pump to keep the windshield cleaner in action. This invention has been incorporated in a pump of the booster type and is shown associated with such a pump having structurally combined therei with a fuel pump. In such an installation it is customary to use exible diaphragms and -to operate these diaphragr'ns by mechanical parts extending into the'engine crank case. It sometimes happens that hot oil from the crank case reaches the vacuum pump diaphragm and burns it so that more or less oil leaks into the pump chamber. The suction ofthe engine thereupon carries the oil to the manifold. This results in high oil consumption, excessive carbon formation on the cylinder, valves, spark plugs, and cylinder head and interferes with the proper operation of the engine.

It is an object of the present invention to overcome such interference with the engine operation and loss of oil by preventing the flow of the oil to the manifold in the event of a leak through the pump diaphragm.

It is a further object of the invention to return the escaping oil to the engine crank case.

The accompanying drawings illustrate structural' embodiments to attain the above objects. In the drawings Fig. 1 shows in vertical section a combined pump having my invention incorporated therein.

Fig. 2 is a section on line 2 2 of Fig. 1. Fig. 3 is a perspective of afloat used in a chamu ber of the vacuum pump.

Fig. 4 is a section on line 4-4 of Fig. 2. Fig. 5 is a section on line 5-5 of Fig. 1. Fig. 6 is a section on line 6-6 of Fig. 2. Fig. 'I is a side elevation of another form of the invention. l

Figs. 8 and 9 are sections on lines 8-8 and 9-9 Of Fig. 7.

Referring by reference characters to the drawings, numeral 9 designates the crank case of an engine of a motor vehicle. At II is an engineoperated cam actuating in one direction of reciprocation a push rod i9 guided as shown.

The pump is formed from three castings I5, Il, and i9. Casting I5 contains the operating mechanism for the upwardly positioned fuell 5 pump and the downwardly located suction pump.A The upper casting I? is clamped to casting i5 together with a diaphragm 2i therebetween. The diaphragm 4constitutes the movable wall underlying the fuel pump chamber 29. Tl'iefuel pump 10 is not a part of this invention and the showing of the suspended lter cup'25 and the air dome 2l are intended merely to illustrate well known parts of such a pump. A spring 29 beneath the diaphragm biases the diaphragm toward dls- 15 charge position and a rod 3i connected to the diaphragm functions to pull down on the same to make a suction stroke. Within the casting I5 is a pivot pin 33 upon which rocks a lever 35. The lever is rocked in a clockwise direction by the 20 cam li and the rod I3 as will be obvious upon an inspection of the drawings. The lever is biased for rocking in a counter-clockwise direction by a 'spring 3l. Also rocking on pin 33 is a link 39 having an interlocked connection with pump rod 25 3i. The link 39 has a part 4I adapted to be engaged by the lever 35 as it rocks in its clockwise direction. Such a rocking produces a suction stroke.

'I'he third casting I9 clamps a diaphragm 43 30 between itself and the middle casting I5. The casting I9 has a pocket 45 within which a spring 4'I is seated. This spring pushes upwardly on diaphragm 43 to enlarge the chamber 49 beneath the diaphragm, this chamber 49 being the cham- 35 ber of the suction pump. 'Ihe downward discharge stroke of the pump diaphragm is made by a link 5I interlocked with a pump stem 53, rotatable on pin 33 and adapted to be engaged by an arm 55 of lever 35. The bottom of casting 49 I9 is closed by a cover 5l secured by fastening means 59. What may be called a horizontal wall 6I forms the bottom of the vacuum pump chamber 49. 'Iwo

segmental chambers

63 and 65 are seen beneath the wall. the segmental chambers 45 being formed by radial walls in casting I9 as shown by Fig. 5. Chamber is in communication with the windshield cleaner by a conduit 51. Chamber 63 communicates with the engine manifold by means of a conduit 59. Secured by fas- 50 tening means 'Il to the wall 6I is a plate 19. Beneath this plate an opening is made through wall 6I at 15. 'Ihis opening and an aperture 11 in the plate 'I3 aord communication between the vacuum pump chamber 49 and segmental cham 5l ber 65. In this passage is secured a valve seat 19. Engaging the seat is a disc valve 8| held in position by a spring 83, the spring being in abutment with an apertured member 85. The spring yieldably permits the flow of air from the chamber 65 to the chamber 49. Plate 13 has another opening 81, about which seats a disc valve 89 pressed upwardly by a spring 9| seated in a recess 93 of the wall 6I. Through the bottom of this recess is shown an opening communicating with chamber 63. Chamber 63 is formed with a portion circular in cross section marked 95 within which is a iloat 91 carrying a cone-shaped valve 99 adapted to seat in the end of the passage |0I communieating with a bore |03 extending to the conduit 69.

The lower casting I9 is formed with a horizontal passage |05 communicating with chamber 63. Externally this passage is closed by a plug |01. From passage |05 there is an upwardly extended passage |09 the latter formed of two diameters to form a shoulder. Engaging this shoulder and closing the'passage is a ball valve III, the valve being yieldingly held by a spring I I3 acting against a xed abutment II5. The diaphragm is apertured at IIT to register with the passage |09 and an aperture which is formed in the spring abutment. Above the diaphragm the intermediate casting I5 is formed with a conduit I I9 which, together with conduit |09, constitutes a passage from the region 63 to the region above the diaphragm and therefore to the crank case. The ow through this passage is possible only when pressure in chamber 63 is sufcient to overcome the load impressed on valve I I I. By this means, if a leak occurs through a damaged diaphragm, not only will the escaping fuel cause the float to rise and close the passage IOI, |03 but the pumping action will continue to keep the Windshield cleaner in operation. After the float closes the communication between the manifold and the pump and windshield cleaner the check valve serves to deliver air drawn from the windshield cleaner into the pump chamber 49 to thecrank case, and the oil entering the vacuum pump chamber is then also exhausted through the check valve back to the crank case. Therefore, the pump cntinues to keep the windshield cleaner in operation, the discharge of oil to the manifold is checked and loss of oil from the crank case is prevented.

The float is guided by a stem |95 projecting from the cap as shown.

The operation is substantially the same as in -the form first described. When the diaphragm |51 is intact air is drawn into the pump chamber through the inlet valve (not shown) and discharged through valve I6I. The air passes through conduit |63 into the trap chamber and out through passage |93, outlet |13, and conduit |15 to the engine manifold. In the event of oil leakage through the diaphragm, oil passes through valve |6I, conduit |63, and collects in the trap chamber |65. The oat then rises and closes the valve |9I. The-oil and air from the continuously operating pump then lift the spring-loaded valve |8| and the dischargeJ occurs into the crank case through the wall opening |19.

The pump is no longer a booster pump. It performs then the Whole duty of` exhausting the windshield cleaner motor and delivers the air to the engine crank case instead of to the engine manifold.

I claim:

1. In combination, a vacuum booster pump having a pump chamber, a plurality of conduit means adapted to connect said chamber with an engine manifold anda windshield cleaner, respectively, said pump having a exible diaphragm, means extending into the engine crank case and adapted to ex said diaphragm, a trap between the pump chamber and the manifold conduit to collect oil escaping through a defective diaphragm into the pump chamber, a valve carrying oat in said trap movable in response to collecting oil to close the communication between the manifold and the windshield cleaner and pump, and a check valve controlled discharge passage between said pump and crank case whereby the pump may continue to operate the windshield cleaner unassisted by engine vacuum and whereby escaping oil may be returned to the crank case.

2. In a suction booster pump for operating the windshield cleaner of a motor vehicle, the combination of a casing member, a movable diaphragm operable to constitute in cooperation with a part of said casing a variable volume pump chamber, means to reciprocate said diaphragm, said casing also formed with an additional postpump chamber, a valve between said variable volume chamber and said additional chamber, a conduit connected to said variable volume chamber for communication with a windshield cleaner, a conduit connected to said additional chamber for communication with the engine manifold, a trapping chamber constituting a part of said additional chamber, a `valve carrying float in said trapping chamber movable to close the conduit to themanifold, a valve-controlled outlet passage from the additional chamber whereby the windshield cleaner is kept in action by the pump unassisted by the manifold when the float valve closes the communication with the manifold.

3. The invention defined by claim v2, said outlet passage communicating with the engine crank case to permit the restoration of oil entering the pump chamber of the booster pump.

4. In combination, a vacuum booster pump the chamber of which is adapted to be connected to a windshield cleaner and the manifold of the motor vehicle, a trap to collect oil entering ythe chamber of the pump, means whereby said collected oil closes the communication with the manifold and means whereby the pump may discharge air and liquid subsequent to the closure of said advance communication to the endthat the operation of the windshield cleaner y be continued.

5. In combination, an engine casing, a vacuum pump, an oil trap separate from said pump and 5 adapted to trap oil delivered by said pump to said j trap, said trap having a plurality of discharge outlets, the iirst one of said outlets being normally open and communicating with the engine manifold, and the second of said outlets being nor- 10 mally closed and adapted to be opened and provide communication with the engine casing when the rst outletv is closed.

6. The invention dened by claim 5 togetherv with a valve carrying oat in said trap operable l5 under the influence of liquid collecting in said trap to close said iirst-named outlet.

7. The invention dei-med by claim 5 together with a valve carrying oat in said ,trap operable under .the iniluence of liquid collecting in said -20 trap to close said rst outlet and a spring-loaded valve controlling the second outlet.

8. In combination, a vacuum pump having a pump chamber, rst conduit means adapted to connect said chamber with a windshield cleaner,

25 said chamber having an outlet valve, second conduit means adapted to connect the discharge side of said outlet valve to an engine manifold, said second conduit means including a trap, a iioat in said trap movable in response to the collection of liquid therein to close the communication through said second conduit means.

9. In combination, a vacuum pump having a pump chamber, iirst conduit means adapted to connect said chamber to a windshield cleaner, said chamber having an outlet valve, second conduit means adapted to connect the discharge side of said outlet valve with an engine manifold, said second conduit means including a trap, a iioat in said trap, means carried by said float and movable therewith in response to the collection of liquid in said trap to close said second conduit means, third conduit means leading from said trap, a normally closed valve adapted under pressure to open and permit escape of liquid from said trap through said third conduit means whereby the windshield cleaner may be operated by the pump unassisted by manifold suction and whereby liquid leaking into the pump chamber and trap may be discharged.

10. The invention dened by claim 9, said third A conduit means being in communication with the engine crank case.

GORDON W. HARRY.