US2519106A

US2519106A - Piston pump

Info

Publication number: US2519106A
Application number: US688797A
Authority: US
Inventors: Bobard Emile
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-08-20
Filing date: 1946-08-06
Publication date: 1950-08-15
Anticipated expiration: 1967-08-15

Description

E. BOBARD PISTON PUMP Aug. 15, 1950 2 Sheets-Sheet 1 Filed Aug. 6. 1946 N DUE/77 0f Znw/cB Aqrq E. BOBARD PISTON PUMP Aug. 15, 1950 2 Sheets-Sheet 2 [harem/or 5071/63 50 bare Patented Aug. 15, 1950 Emileiflobard .eann,.Etenee:

A sgSt 6, 6.;S'e .h Frhnee' Augujsfjgog is lai ns-w (Quasi-1:10

invention has for its; oftject imprdi/emnts,

ini piston pumps: bperate'd;v by at rotary" shaft; with a view to reducing their: weight and their bulk and to/ allow for instance their mountihg inside the rim of a pneumatic tire, the rotationvof said wheel: pro'vittihg; inthis;parse-fortthe driving of the pump- The accompanying drawing illustrates in. two examples the principle: my'hwntion.

Figs. 1 and. 2: are eross'i-sections respective through linelerl'of li'ig'. Zahdthibngln Iih'e: ofsrEig; 1 off themxmp 'considere'dhas a; whole Figs 3: and 4; show: another form; of thei -invenre. tion with the 'disjoonnec'ting mechanism two; diffierentpperatin'g postitions'pas in, thexdireee tionofthe arrow ofLEig'. 2;

The: -'pum p i'llustiatteclzizx-E'igs;v anda=2i includes: chiefly two cylinders l and l inside which-may reciprocate tlwo; pistons 2: and 2;" by vthe two: rods 3.- andJB' -W According; toa thine; iheven ti'on the. reciprocating 'moxriemeri't on thesepisto'ns controlled bya shaft- BJai'r'anged: -inside theagrmipi of members formed: by therc'ylinders; l= and. 11 the: flap: valve box 6, the'piston rods; 3e and 3., and the letters 8;!" serving: for; theeontmll at said: rods. T this purpose: the; shaft Smames. a. 0am I with. Whieh cooperate? the

rollers

8 and 8 caxrriedvhy: the/levers; 9 and; 91' pivotaliy-seclinediait t0; and, 151" to: the. rods '3; anda '3 ofthe pistons-T These: levers are: bent; for the neason disclosed hereinafter" ancL are pivota'fly secumed 'te, av dum men pivot H. v

It is apparent from the that thfrotair tion of the zand. ofthe cam; lyrigicl therewithsha sa for 'itsgact ion to-make the" twolevers 8; air-@193 rock mundthepivot -H so -as toprovide the rising and" sinking movement; f; thegpistonsvi anhzi; 2". The outline of the am 'le is defined im'the example illustrated in. a -mannensueh as winiqamsince, for each revolution a 'su'ction 'stroke. and a; delivery stroke for eachipistonm To ensure "a regmztr oixtput; the-butlinept the cam is designed sotas twensure' a; "ifispl'aeerrient o'fithe pistonsiwhiohis rbpdrtfonai to the single oiifotation oi the sh'a ft takmg intoihcoount' the corrections which it is necessiairy to-bflng thereto ion the reasons disclosed hereinafter;

The; pump dilustregted is= designedzs'oaas to ailIOW the operation. of 'thee'csimta nd do nperating memai end thebsha-ftti rotates ans-mean out shaft. However, with the: monn'ti "ii I 6 (588,797

Wall is subetantimi u shapeit tress;- setiont Fennelwali's I ai'a'd no erase the id'bfi the casing me lower face at aura-a totn'e pump body v twec nnaers. Insinethisban-1- are the 1 itstwobearings Ht, the tweroner e and B ronin over the" the three-be i ings of the rocking levefs aommon pivot 1-? l bent p ge of the were 9 tine-t 9 mehtionee-pi'ece'o n gl" has been prov ifed so to a/HOW s 1. Ievers to pr-meet above the we g 1-2- the open g; of which is reduced to a: while M1wme the pivot H! to Joe immersed A fluid-tight packing l5 is'h'i r iaIng e let of thec'ain sharft. T0 I iSne eteetinn of the drawing-member and of the on any: extraneous: (inject the uppee par 6f the eas mg is entirely mosed by a piote' mg encloisin gfluid-ti htly an the membei s etmti'o'k ling the; pump.

Inorder to protect the sum mechanism against *projebt' from between the piston and-the Walt the yfihcieh, ehiefiy ihthe ease ofi wean iai-i'y oi quidthe direction of the axisof" the minder-errethroug h which the piston rods are eaaptea to slide. iel'dthg fluid-ti ht arran ement a may more o t/er provided between seiarmssana' t'nenooas I:

It'hais ween stated that the oathnept is iieei'gned so iis to enme atpumpautputwmen is pmpdrtionai the angle e f ratiati'on of "e two dead.poims ai pear ge'spectively the; exitsidesaiid inside of each icfl lia 'r alling two 'di'fier'e'nii diameters X; Y forming onewanother "an angle-21. 'cons'equentlynssthe dam: issupposed, torot'ate i n the ctfrection oftl i'e arrow; the passage;

from me outerneaci point drone f the -i'bl lrsQ,

w dribbsffte direction eorresponds to ISU -Pai. e. the delivery-stroke ax me ts the pistons 2 corresponds atothation ti irfiugh of the lpiston is at, every moment pmpoiibibhfl to 'theoiinpiittuietof the-rotation ofi' the eam, wife bath against,-

cylinders will feed the same amount of liquid during periods of different durations.

In order to remove this drawback it is possible to correct the difierence in the speed of operation of the pistons 2 and 2' through a dlfierence reversely proportional thereto of the corresponding cylinder volumes; this may be obtained either as illustrated in Fig. 1 by a difference in the crosssection of the cylinders-l and l or. else by a difference in the strokeo'f the pistons obtained through a difference in length of the lever arms or else by a combination of these two means.

According to my invention, there exists between the two balance beams or levers 9-9 a connection which may be broken and which is such that the rocking of one of the levers in the delivery direction round its pivoting axis produces a rockdirection of suction or reversely. The cam having a constant diameter, it is not necessary in theory to provide a spring for urging the balance beams or levers into contact with it. The disconnection may then be ensured by breaking the connection or more. precisely by transforming their mutual operative connection into a rigid connection whereby the two 'balance beams are set in a position of maximum opening outside the field of action of the cams.

In the form illustrated in Figs. 3 and 4 said conne-ction' is' ensured through a semi-circular link l9 secured to the two levers 9 and 9' at 20 and 20' respectively, said link cooperating with a roller 2p|=carried by a lever 22 which is adapted to rock around a stationary pivot 23 so as to raise andlower said roller. V

When said roller occupies the position shown in Fig. 3 for which the link I9 is centrally located with reference to the rocking pivot ll, said link transmits from one balance beam or lever to the other the rocking motion round said pivot I and the two

rollers

8 and 8 constantly follow the outline of the cam. On the contrary when the roller 2| is lowered as in Fig. 4 this results in a low-' ering of the semi-circular link l9 and in bringing the levers 9 and 9' into a position which is symmetrically opposed for the two levers and outside the field of action of the cam. The two balance beams remain rigidly held in their spaced position until the roller 2| is'raised and again set in its central position with reference to the pivot If.

It will be noticed that the disengagement is operated without any effort of the cam but by a mere lowering of the roller 2|; the engagement may be controlled from a distance through a sheathed cable for instance.

In practice, however, it is necessary to take into account the irregularities in the machinery and the wear of the cam and to provide fora certain elasticity in the connection between the two levers. In the case where, as illustrated, the roller 2| is controlled by a lever 22 rocking'round a stationary point 23, said elasticity is ensured by means of a spring 24 inserted in the control cable 25 engaging a, stationary lug 26. But it is still simpler .touse an arcuate link l9 made of spring steel which urges constantly towards one another the pivots 29 and 29 (through which it is secured. to the levers) i. e. in the direction of the arrow F. Consequently the beams will have a tendency to move ingthe direction of the arrow F-.| and. to urge the rollers against the cam for the connecting position of Fig. 3 in which a line through the pivots 29-49 passesabove the axis of pivot On the contrary in Fig. 4 where'the line through pivots. 29-20- passes below th'e'axis of pivot l the rollers move in the direction of the arrow F2 so as to be held outside the field of action of the cam.

As apparent the above described piston pump assumes a general shape which is substantially circular and is particularly well suited for the mounting end to end of the driving shafts and even for the housing of the entire pump inside the rim ofa pneumatic tire. In the drawing I have shown at 27 the rim of the wheel and at 28 its solid disc. The shaft 5 of said pump is then in one with the shaft of the wheel 21-28 while the stationary casing of the pump is carried by an arm 29 rigid with the frame of the vehicle.

' What I claim is:

1. A pump comprising a rotary driving shaft,

' pump cylinders, pistons adapted to reciprocate ing of the other through the same amount in the therein, levers controlling the pistons, a common pivot for the piston control levers, rollers carried at the outer ends of the levers, a cam mounted on the driving shaft and adapted to control the angular position of said levers through said rollers, means for constantly urging said rollers against the cam elastically, a valve box between the cylinders.

2. A pump comprising a rotary driving shaft, pump cylinders, pistons adapted to reciprocate therein, levers controlling the pistons, a. common pivot for the piston control levers a cam mounted on the driving shaft and adapted to control the angular position of said levers, a valve box between the cylinders and a, container filled with oil inside which the levers and driving shaft are immersed, the levers being bent to an extent such r as will allow the-common pivot to be immersed in the oil bath inside the container, the lever arms on the piston side extending out of the oil container.

3. A pump comprising a rotary driving shaft, pump cylinders, pistons adapted to reciprocate therein, levers controlling the pistons, acommon pivot for the piston driving levers, rollers carried at. the outer ends ofthe levers, a cam mounted on the driving shaft and adapted to control the angular. position of said levers through said rollers, means for. constantly urging said rollers against the cam elastically, a valve box between the cylinders, the inner and outer dead points of the rollers lying on a line to one side of the axis of theshaft, and the cylinder volume. displaced by thepistons differing from one piston to the other for compensating the result of the unequal operation of the levers.

4. A pump comprising a rotary driving shaft, pump cylinders, pistons adapted to reciprocate therein, levers controlling the pistons, a common pivot forthe piston control levers, rollers carried at the outer ends '.of the levers, a cam mounted on the driving shaft and adapted to control the angular position of said levers through said rollers, means for inter-engaging the levers and urging'them to either side of the cam and means for controlling the. position of said last means for disengaging as desired the levers and rollers thereon with reference to the cam, and a valve box between the cylinders.

5. A pump comprising a rotary driving shaft, pump cylinders, pistons adapted to reciprocate therein, levers controlling the pistons, a common pivot for the piston control. levers, rollers carried at the outer ends of the levers, a cam mounted on the driving shaft and adapted to control the angular position of said levers through said rollers an arcuate' link 'pivotally secured to each lever through the corresponding end, means for making said link move between a central position with reference to the pivot between the levers for which the levers are in co-operating position with reference to the cam and an eccentric position for which the levers are moved away from said cam, a valve box between the cylinders.

6. A pump comprising a rotary driving shaft, pump cylinders, pistons adapted to reciprocate therein, levers controlling the pistons, a common pivot for the piston control levers, rollers carried at the outer ends of the levers, a cam mounted on the driving shaft and adapted to control the angular position of said levers through said rollers, a resilient arcuate link pivotally secured atgits ends to said levers, means for moving said link between a central position and an eccentricposition with reference to said common pivot, said levers cooperating with said cam in said central position of the link, and said levers being" in inoperative relation to said cam in said eccentric position of the link, the elasticity of said link urging towards one another its points of connection with the levers and urging said levers into their operative or inoperative position accordingto the position assumed by said link-moving means, a valve box between the cylinders.

7. -A pump comprising a rotary driving shaft, pump cylinders, pistons adapted to reciprocate thereirrlevers controlling the pistons, a common pivot for the piston control levers, rollers carried atfthe outer ends of the levers, a cam "mounted .on the driving shaft and adapted to control the angular position of said levers through each lever through its corresponding end, a roller engaging said link, and means for controlling the positionof said roller with reference to said common lever pivot between the levers and thereby theoperativeness of the levers with reference to thecafn, a valve box between the cylinders and a casing enclosing the different above-mentioned elements.

8. In combination with a vehicle wheel, a wheel shaft, a support, a pump comprising pump cylinders, pistons adapted to reciprocate therein, leversjjcontrolling the pistons, a common pivot for'the piston control levers, rollers carried at the'outer ends of the levers, a cam mounted on thelwheel shaft and adapted to operate said levers means, for moving said link between a central position and an eccentric position with reference to said common pivot, said levers cooperating with said cam in said central position of the link, and said levers being in inoperative relation to said cam in'said eccentric position of the link, a valve box located between said cylinders, and a casing enclosing the cylinders, pistons, and valve box secured to said support.

9. A pump comprising av rotary driving shaft, pump cylinders, pistons adapted to reciprocate thereirii' valve means connected with said cylinders, levers controlling said pistons, a common pivot for the piston control levers, a cam mounted on the drivingshaft and adapted to control the angular position of said levers, resilient means for constantly urging said levers toward said cam, the angular travel of said cam on the delivery stroke of one piston being greater than its angular travel on the delivery stroke of the other piston, and the areas of said cylinders and strokes of said pistons being constructed and arranged to compensate for said unequal travel and to equalize delivery from said pumps.

10; A pump comprising a rotary driving shaft, pump cylinders, pistons adapted to reciprocate therein, valve means connected with said cylinders, levers controlling said pistons, a common pivot for the piston control levers, a cam mounted on the driving shaft and adapted to control the angular position of said levers, means interengaging said levers and urging them oppositely toward the sides of the cam, and means for controlling the position of said interengaging means for moving as desired the levers into or out of operative relationship to the cam.

11. =A pump comprising a rotary driving shaft, pump cylinders, pistons reciprocating therein, levers controlling the pistons, a-common pivot for the piston control levers located within the compass cream levers and their connections to said pistons, a cam mounted on the driving shaft and adapted to control the angular position of the levers, resilient means for constantly urging said levers toward said cam, and alvalve box located between said cylinders and associated therewith.

12. Pump structure as claimed in claim 11 having a container filled with oil within which said levers and common shaft and driving shaft are immersed with portions of said levers extending out of said both.

"13. A pump comprising a rotary driving shaft,

pump cylinders, pistons adapted to reciprocate therein, piston rods and levers associated with said shaft and pistons, a valve box located between the cylinders forming with said cylinders and the rods of said pistons a U-shaped whole, and means for the conversion of the rotary movement into reciprocating movement, said converting 'means being disposed between the two branches of said U, and a casing comprising two lateral parallel walls and a lower Wall to which are secured the cylinders and the valve box, a container filed with oil inside said casing and within which said levers and driving shaft are immersed.

f 14. A pump as claimedin claim 13 having a cover adapted to cap the casing .for protecting the piston rods, levers, shaft and container against any detrimental outer action.

'15. A pump as claimed in claim 14 having an auxiliary hood capping the cylinders for preventing any projection of the liquid out of the cylinders.

. EMILE BOBARD.

REFERENCES CITED The following references are of record in the 1 fil-e. of this patent:

UNITED STATES PATENTS Number Name Date 798,506 Hall Aug. 29, 1905 1,382,450 Baker June 21, 1921 2,240,371 Linch et al Apr. 29, 1941 2,317,636 Parker Apr. 2'7, 1943 2,319,718 Brooks May 18, 1943 2,369,694 Trippensee Feb. 20, 1945