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Dec. 24, 1946. w. H. DE LANCEY 2,413,034 FLUID METER Filed June 2, 1944 3 Sheets-Sheet l \ \l \ \ 3 INVENTOR, b62210: 1X kid/way ATTORNEY. Dec. 24, 1946. w_ H. DE LANCEY 2,413,034 FLUID METER Filed June 2, 1944 3 Sheets-Sheet 3 Patented Dec. 24, 1946 2,413,034 UNITED STATES PATENT OFFICE 2,413,034 FLUID METER. ' ‘ “ Warren H. De Lancey, Spring?eld, Mesa, assign or to Gilbert & Bark Manufacturing Oom Dilly. West Spring?eid,orMesa, a corporation of Massachnsetis Application June 2, 1944, Serial No. 538,485 9Claims. (Cl. 73-247) 2 This invention relates to improvements in meters or the reciprocating piston type. Meters of this type embody pistons, which are driven by the ?uid being measured, and a. crank shaft for actuating the valve of the meter and for operating a. counter or registering mecha nism, together with provision for lost motion in the connections between the crankshaft and at least one of the pistons and a calibration stop for such piston to control the amount of such lost motion and thereby vary the stroke of such piston and thus the displacement of the meter. The general objects of the invention are to simplify and improve the construction of a meter of the stated type to the end that it may be 16 manufactured at relatively low cost and yet give better and more emcient performance; to pro vide a rugged construction which is calculated to have a long life of useful service: to provide for close accuracy of measurement; to provide 20 for smooth drive of the counter or registering mechanism without substantial pulsations; to provide for low friction loss; to provide for quick purging of the meter of air when initially start ed; and to prevent hydraulic binds, such for ex ample as sticking of the valve. More particularly, the invention provides a sides 01' the pistons so that the connecting rods are always under tension and never subject to compression which would buckle the rods. A further object of the invention is to provide in a meter of the class described, a connecting rod which is of relatively thin, ?at form and can be made in a punch press, and to provide a novel form of wrist pin, which is non-rotatable in the connecting rod, and a novel form of connection between all the connecting rods and the crank pin to enable these thin rods, which of them selves do not provide adequate bearing area, to be successfully used. These and other objects of the invention will best be understood as the detailed description proceeds and they will be pointed out in the ap pended claims. The invention will be disclosed with reference to the accompanying drawings, in which Fig. l is a top plan view, partly in section, 01' a meter-‘embodying the invention; Fig. 2 is an end view 01' one of the cylinder heads, showing part of the calibrating means and the sealing means therefor; Fig. 3 is a cross sectional view taken on the line H of Fig. 1: Fig. 4 is a bottom plan view of the inlet valve meter, having a plurality oi’ cylinders and pis shown in Fig. 3: tons, with means for admitting ?uid to the in Figs. 5, 6 and 7 are sectional views taken on her ends of the cylinders,,whereby the pistons 80 the lines 5-5, 8—,6 and 1-1, respectively, of are forced outwardly by the high-pressure ?uid. Fig. 3: This arrangement enables the calibration stop Fig. 8 is a. sectional view taken on the line H to be of simple form and located in the cylinder of Fig. '4‘; and head where it is conveniently accessible. The Fig. 9 is a fragmentary sectional view taken former disadvantage that the arrangement re sults in a high-pressure upward thrust tending 35 on the line 9-9 of Fig. 3. Referring to these drawings; the meter in to unseat the valve, is overcome by the use 01' cludes a. casing comprising a body member I (Fig. a chamber in the valve which is in constant com 1), having a central chamber 2 and three cylin munication with the high pressure ?uid and which has one wall on which the ?uid acts in a 40 ders 3. spaced 120 degrees apart and radiating from, and communicating at one end with, the direction such as to seat the valve and to an ex central chamber. The latter has a large open tent such as to exceed the lifting thrust on the ing 4 (Flu. 3) in its bottom wall and such wall valve and a second and opposed wall independ is faced off to receive a bottom closure plate 5, ent of the valve to transfer the reactive thrust which is secured to the body with a gasket 8 of the ?uid pressure to the casing. By this ar rangement, the valve may be held to its seat 45 clamped therebetween by a plurality of cap under relatively low pressure, thereby avoiding rapid wear of the valve and its seat and avoid ing sticking of the valve. ‘ Another object of the invention is to provide in a meter of the class described a piston con struction of simpli?ed and improved form, sus ceptible to manufacture by molding and capable of being made of plastics if desired. Another object of the invention is to provide in a. meter of the class described, connecting rods which are relatively ?exible and means for supplying the high pressure liquid to the inner screws, one of which is shown at l in Fig. 3. This plate 5 has a ?ange 8, with a plurality oi’ holes, such as 9 therethrough, whereby it may be fas tened to the outlet of an air separator, for ex 50 ample, or to any other suitable means from which liquid is supplied to the meter. Each cylinder 3 has its outer end closed by a head II which is secured to the end of the cylinder, with a gasket ll clamped therebetween by a plurality of cap 55 screws l2 (Fig. 2). The meter casing further includes a top cover 13 having a ?ange II which is fastened to a faced-oil’ part of the top oi’ body I with a gasket IS clamped therebetween, by a anaoas 3 . plurality-of cap screws It. The space within ?ee ‘ cover ll constitutes an outlet chamber 11. latter has an outlet passage I! (Fig. 1) through the ?ange it, which is adapted for connection to an outlet pipe. The three connecting rods 41 have their inner ends overlapping and superposed one upon an other. The upper and lower of such ends, shown in Fig. 3, are respectively oi’i'set upwardly and downwardly to lie on opposite sides and flatly against the faces of the uno?set central end. The inlet to the meter is by way cl.’ a passage These superposed ends are mounted upon a 2! which is provided in the closure plate 5 (Fig. ?anged bushing 52 with freedom to turn thereon. 3) and which opens into the central chamber 2. The bushing is mounted to turn on a stud 51, An inwardly-opening, valve 2| controls the ad forming the crankpin 01' a crank 54. which is mission of liquid through passage 20 and prevents 10 ?xed to the lower end of a shaft 55. The latter return ?ow. The plate 5 has a seat 22 for valve ‘ is rotatably supported in upper and lower bear 2| with which seat the valve packing (in the ings U4’ and 55' formed in a central hub 58. sup shape of a torus ring 23 of rubber or the like) ported by spider arms 51 in an outlet passage” cooperates. The valve has a depending stem 24 leading vertically upwardly from the center of with wings 25 (Fig. 4) which guide it in passage 15 chamber 2. The upper bearing 54' is a sleeve 20. The valve ‘it also has an upwardly extending bearing of hardened steel. The lower bearing 55' hollow stem 26 which is slidably guided in a plate is an anti-friction bearing, such as a ball bearing, 21, secured at its ends by screws 28. one to each and is designed to take both the radial and axial of a pair of posts 29 upstanding from plate 5. load. The shaft projects upwardly above the top 20 A spring 30, coiled around stem 26, acts between of body I and into the outlet chamber II, where _ plate 21 and the upper face of valve 2| with a it is slidably keyed to a distributing valve and tendency to close the valve. A back-?ow passage 3i extends through both the hollow-stems 24 and 2B and the valve II. A connected by means to be described to drive a counter or registering mechanism. The distributing valve comprises a body 58. valve 32, which is mounted in that portion of 25 which may be of molded plastic material, and a passage ll having the larger diameter and which facing 60, which may be of carbon and which is pressed upwardly by a spring 33, cooperates rotatably engages ?nished valve seat surfaces 6| with a seat formed at the intersection of the large on the top wall of body I. These surfaces are and small portions of thepassage to control the the upper end faces of inner and outer walls 62 latter. Valve 82 has vanes 34 (Fig. 5) to guide it 30 and 63, respectively, and radial division walls 64. in the small portion of passage St. A plate 36, The inner wall 62 surrounds the central outlet having a plurality of holes 38 therethrough. is passage 58 and the walls 82, B3 and 64 together secured by screws 31 to the lower end of the valve mark off a circular series of arcuate ports 65 stem 24 and acts as a seat for spring 33. The surrounding said central passage. The walls 82 35 passage it enables back flow of liquid to relieve and 63 are not truly circular but vary in radius pressure due to expansion or the liquid, valve 32 by a distance at least equal to the thickness of opening whenever the force due to pressure of the walls. This arrangement enables any gum, the liquid and acting on the valve exceeds the which may be deposited between the valve and force due to the spring 33. its seat, to be wiped on’ rather than carried 40 Slidably mounted in each cylinder 8 is a piston around and around in a circle and accumulate to 38. As herein shown, each piston includes two cause sticking of the valve. The ports 65 are parts 3! and Ill, which are made oi’ plastic or any connected by passages 66, cored in body I, one other suitable material and between which the above each cylinder, to the clearance space 61 circular portion of the piston leather 4i and its in the head of such cylinder. The carbon face washer 42 are clamped. Member 39 is recessed 45 80 or the valve has two arouate ports 68 and Bil to receive an annular spring 43 for presing the therethrough. located 180 degrees apart. The ' annular portion of the piston leather against the upper part of the body 59 has a cylindrical recess wall of the cylinder. The member 39 has a cen 10 in its upper face having a circular bottom 1|. tral cylindrical hub 44 which fits into a corre This wall is spaced from the parallel carbon block spondingly-shaped recess in member 40, whereby 50 60 by an endless ?ange 12 of the con?guration these parts are brought into coaxial relation. The members 39 and 4|! are held together by a plurality of cap screws 45. The hub 44 has a slot 46 therethrough to provide clearance for the con necting rod 41. The member 40 has a similar slot 48 for the same purpose. Located one on shown in Fig. '7 and by several ?ns 13 radiating from such ?ange. The block Bil is secured to body 59 by screws 14 which pass through these ?anges and ?ns. The flange 12 marks oil’ a space 15 which constantly communicates at its inner end with the central passage 58 and at its outer end with the inlet port 68. There are holes 15 in the wall ‘II which connect cylinder 10 with each side of the slot 46 and extending at right angles thereto, are two recesses 49 extending from the outer face of the hub inwardly and terminat space 15 but, except for said holes, the port 58 ing with semi-cylindrical inner sides. These re 60 in the carbon block and the central hole 11 in cesses are U-shaped in cross section and.are in the latter, the space is closed. The arcuate port tended to receive, one in each, the cylindrical ends 69 at its upper end constantLv communicates with of a wrist pin 50. Therecess 48 in at least one a space ‘I8 between two ?ns 13, which space at its of the pistons is somewhat greater in depth than outer end is in constant communication with the as the diameter of the cylindrical ends oi the wrist outlet chamber ll. pin so that there is a certain amount of lost When the port 88 of the valve communicates motion between such piston and its connecting‘ with the passage 86 of one cylinder, the outer end rod. Centrally between its ends, the wrist pin is of that cylinder is connected to the outlet cham formed with a portion 5i oi’ hexagonal or other ber i1 and the piston in that cylinder will move non-circular shape, which closely fits in a corre 70 outwardly by the high pressure in inlet chamber spondingly-shaped hole in the outer end of its 2 to expel the liquid from such cylinder. The connecting rod. The wrist pin cannot turn in its crank 54 will be rotated by the pull of the con connecting rod, which is oi.’ thin rectangular cross nectlng rod or rods of the piston or pistons that section, but. is forced to turn in the recesses 49, 75 are being pushed outwardly by the high inlet which provide bearings of adequate area. 2,418,034 5 pressure. At times, only one piston will be pushed outwardly and at other times two of the pistons will be pushed outwardly. The pressure strokes of the pistons overlap to some extent and enable a substantially smooth movement of the crank and a substantially uniform flow of liquid free from pulsations of any substantial degree. As the valve moves to bring its port 68 into com munication with. a port 88 of a cylinder, the piston in such cylinder is being drawn inwardly by the crank 54 and liquid will enter the cylinder and eventually ?ll the same. to be held in place by a pin I09 which is passed through one of the holes III! and one or the holes I". The pin may then be held in place by a wire I99 passed through a hole H8 in the outer end of pin I08 and through two adjacent un occupied holes I05 and having its ends brought together and held by a lead seal III. The spac ing of the holes III‘! is such as to enable the pin III! to hold wheel I“ in 36 positions of angular adiustment. When the abutment has been moved to the desired position, one oi’ the holes I05 may register with one of the holes I?'l in A piston is mounted in the cylinder ‘I0 in the which case the pin I08 is passed through these Vupper part oi‘ the valve body 59. This piston registering holes. If no one of the holes I" includes a die-cast member, having a circular 15 registers with any hole II", the wheel II" is plate ‘I9, with a central hub 80 and a plurality turned until the two holes I05 and I 01 that are of studs BI upstanding therefrom; 3. depending nearest to registering, do register. And the max hub 82; and a marginal spring support 83 or imum movement necessary to bring two such arcuate section. Integral with and upstanding from hub 80 is a pinion 84. The hub 82 is 20 holes into register is no more than 10 degrees. Assuming that screw IDI has 20 threads to the mounted on the upper end of shaft 55 and is held inch, the maximum axial movement of abutment thereto by a screw 85 which passes through 99 from its exact position of adjustment to one pinion. 84 and hub 80 and threads into shaft 55. where wheel I04 can be held by pin I08 is no A spring 86 encompasses hub 82 and acts between more than one thirty-sixth of ?ve one~hun wall ‘II and plate 19. The circular portion of dredths of an inch or .00139 and ii the cylinder the piston leather 81 is superposed on plate ‘I9 is assumed to be two and one—half inches in and a metal washer 88 is superposed on the cir diameter, the maximum displacement is seven cular portion. Both said portion and the washer one-thousandths of a cubic inch. The meter may have holes to receive studs BI and a central hole thus be adjusted with exceedingly close accuracy. to fit over hub 80. The upper ends of the studs The arrangement whereby the ?uid is admitted BI are rivetted over upon the washer to hold the to the inner ends of the cylinders 3, While not piston leather to plate ‘I9. The annular ?ange new of itself, is important in that it enables the of the piston leather engages the circumferential use of simple, inexpensive but nevertheless reli wall of cylinder 10 and is pressed thereagainst by able means for calibration and enables such an annularly-formed coil spring 89 resting on means to be placed in a conveniently accessible support 83. location. Thus, a simple abutment 99, adjustable The register driving means includes a shaft 90 by being screw-threaded into the head III of one mounted in upper and lower bearings, one in the of the cylinders, su?lces for the purpose. This lower wall of a. cylindrical depression 9| in the abutment is located in the path 01' the piston upper wall of cover I9 and one in a plate 92 which closes the upper end of said recess. This plate 40 and the latter is forced against the abutment, 92, with an intervening gasket 93, is clamped to thereby limiting its stroke. There is lost motion around the shaft. The seal rings are pressed against the upper and lower walls of chamber chamber ‘I0 formed therein and in constant com between-I wrist pin 50 and its piston and more or cover I3 by a plurality of cap screws 94. Fixed less of this lost motion is taken up according on the lower end of shaft 90 is a gear 95 which to the location of the abutment, whereby the meshes with pinion 84. Fixed on the upper stroke of the piston and thus its displacement end of shaft 90 is one section 98 of a coupling may be varied. adapted to receive a mating coupling section on It has heretofore been considered objectionable the lower end of the drive shaft 01' the register. to have the pistons thrust outwardly by the high Within the chamber 9i are upper and lower pressure ?uid because there results a high pres seal rings 91, each mounted on shaft 90 and 50 sure upward thrust tending to unseat the valve. pressed apart by an intervening spring 98, coiled To overcome this objection, the valve has the munication with the passage 58, whereby the high 9| and they tightly fit and revolve with shaft 90. pressure ?uid may act von the bottom wall of the thus preventing leakage from the meter around chamber and press the valve to its seat with a the shaft. force greater than the upward force tending to For calibrating the meter, means are provided unseat the valve. This chamber 10 has a second for varying the stroke of one of the pistons, such and opposed wall, independent of the valve, in as that shown in Fig. 3. An abutment 99 is adapted to be engaged by this piston to limit its 60 this case the piston 90, which transmits the re active thrust of the ?uid in chamber 19 to the outer stroke. This abutment is formed on the casing. In this case, fluid under outlet pressure inner end of a cylindrical shank I00 having its (several pounds per square inch less than the outer end Illi threaded into a central hub I02 on inlet pressure) tends to move the piston down the head ill of the cylinder. A seal ring I03 in wardly. The unbalanced thrust on the piston 80, this head engages the smooth shank Hill and pre tending to lift it and shaft 65, is taken by the vents leakage from the cylinder along the shank antii‘riction bearing 55', which is designed for and screw. Fixed to the outer end of screw “II this purpose, and transmitted to the casing I. is a wheel I04 having .a circular series of twelve It is not possible to perfectly balance valve 59 equally spaced holes Hi5. Radiating from hub because the pressures acting on it vary as it I92 are a series of arms £06 each having near its 70 rotates and according to its angular position. outer end a hole I01 spaced radially from the axis of wheel IN by the same distance as holes I05. The upper and lower holes lill in Fig. 2 are However, the predominating force, tending to hold the valve to its seat is made as low as feasible. In addition, the carbon facing of the valve pro spaced 100 degrees fromthe intermediate and for a low coei?cient of friction. right hand hole I01. The wheel I“ is adapted 75 vides The piston construction is simple and inexpen 9,418,084 sive o manufacture. The parts 3! and I! may be nfade by molding, as from Bakelite or other suitable plastic material, and require no ?nish ing other than tapping of the holes for the screws N, which hold these parts together. The con necting rods can be made in a punch press and the wrist pins can be made in an automatic said chamber with its axis at right angles to the axes of said cylinders, a crank on the inner end of said shaft, connecting rods between said pis tons and crank, there being lost motion in the connections between said crank and one o! the pistons, a calibration stop adjustably mounted in the outer end of the cylinder containing the last-named piston and located in the path there of; said casing having an inlet passage opening screw machine. These rods being subject only to tension may be made of small cross section. said chamber, an outlet chamber and an They are light weight and relatively ?exible and 10 into outlet passage leading out or said central cham would buckle under compressive force if the pis ber through said wall; a valve on the outer end tons were forced inwardly by the high pressure of said shaft and seating on said wall, said casing liquid. The non-circular central part of the wrist having passages one for each cylinder each lead me has a press lit in the connecting rod. To ing from the outer end of its cylinder to and 15 assemble the parts of the piston, the inner end terminating with a port in said wall, said ports of a connecting rod is passed through the slot adapted to be connected successively by said valve in the part 38, bringing the wrist pin against to said outlet passage and subsequently to said the outer face of such part. Then, the piston outlet chamber, said valve having a chamber in leather 48, its washer 42 and spring 43 are laid constant communication with said outlet passage, 20 in place on part 38, after which part ill is super said last-named chamber having two opposed posed on part 39 and held thereto by the screws walls, one chamber wall being on the valve and 45. In use, each wrist pin turns entirely in its the thrust of the high pressure ?uid thereon be recess in the piston, thereby providing the ade ing in a direction such as to move the valve to quate bearing area that could not be had in a connecting rod of the type described. The con 25 its seat and being greater than the thrust of the high pressure liquid tending to unseat the valve, nection of the wrist pin between two parts of the the other chamber wall being independent of the piston is novel and this arrangement allows the valve and taking the reactive thrust of the high wrist pin to be located far out in the piston. pressure fluid in said chamber and transmitting‘ The connecting rod can thus be made longer and it to said casing. thus have less angularity with less resulting side 2. In a fluid meter, a casing having a plurality thrust on the piston. The bushing 52 provides of cylinders radiating from a central chamber, a connection having the requisite bearing area a plurality of pistons one in each cylinder, 9. between the inner ends of all the connecting rods crankshaft mounted centrally in one wall of said andthe crank pin. The connecting rods merely chamber with its axis at right angles to the axes articulate on the bushing. The rotary movement of said cylinders, a crank on the inner end of said is between the bushing and the crankpin. This shalt, connecting rods between said pistons and arrangement enables the use of the simple, in crank, there being lost motion in the connections expensive form of connecting rod, herein de scribed. between said crank and one of the pistons, a' The meter has high ei?ciency because of the 40 calibration stop adjustably mounted in the outer end of the cylinder containing the last-named reduction of friction losses. Such losses are kept piston and located in the path thereof; said cas low because of the low pressure needed to hold ing having an inlet passage opening into said the valve to its seat, the low coeihcient of friction chamber, an outlet chamber and an outlet pas between the ‘valve and its seat, and the use of sage leading out of said central chamber through the anti-friction bearing to take the unbalanced said wall; a valve on the outer end of‘ said shaft thrust on the crankshaft. Long life results from and seating on said well, said casing having pas these same factors. The low pressure holding sages one for each cylinder each leading from the valve to its seat, the facing of the valve, the outer end of its cylinder to and terminating the use of a hardened bearing 54' and of an anti with a port in said wall, said ports adapted to friction bearing 55’ result in materially lessened be connected successively by said valve to said wear and thus materially increased life. outlet passage and subsequently to said outlet The meter is free from pockets in which air chamber, said valve having a cylinder therein, may be trapped and, when initially started up a piston in said last-named cylinder ?xed to said will quickly purge itself of air. It is not necessary crankshaft and subjected on its inner face to the to pump more than 10 to 15 gallons of liquid high pressure in said central chamber and on its before all air will be driven out of the meter. outer face to the lesser pressure in said outlet The use of three cylinders, spaced 120 degrees chamber, and hearings in said casing for said apart, results in a smooth flow oi liquid from shaft including an anti-friction bearing to take the meter substantially tree from pulsations. the unbalanced thrust on said crankshaft. The strokes of the pistons overlap in part and 3. In apparatus of the class described, having in such a way as to give substantially uniform a piston made up of inner and outer members. rotation of the crankshaft. The driving of the a. piston packing between the members, and counter or registering mechanism is thus e?’ected means for clamping the members and packing smoothly and without pulsations of any material 65 together, and‘ having a crankshaft and crank degree. . therefor; a connecting rod of thin ?at form con The invention thus provides an improved meter nected at one end to said crank, and a wrist construction designed for manufacture at low pin ?xed in the other end of the connecting rod, cost. for efficient and smooth operation. for 'the inner member having a slot therethrough close accuracy of measurement and for a long 70 and through which the outer end of the connect life of useful service. ing rod passes, one member having a recess in I claim: one face to receive the wrist pin and provide a 1. In a ?uid meter, a casing having a plu bearing therefor, said recess being closed by one rality of cylinders radiating from a central cham face of the other member. ber, a plurality oi pistons one in each cylinder, 4. In apparatus or the class described, having 9. crankshaft mounted centrally in one wall of 75 '_ 2,419,034 .\ _ 9 ‘ fromthe chamber when thefiuid in the chamber apistonmadeupof inner and outer members,a exceeds a predetermined pressure. pistonpac?nghetweenthememberaandmeans for clamping the members and pacmng'togethef'. 8. In a. ?uid meter. a casing having a plurality _ of cyiindersradiating from a central chamber. a and having a crankshaft and crank therefor: a" plurality of pistons one in each cylinder, a crank shaft mounted centrally in one wall of said cham ber with its axis at right anglestotheaaesof‘ said cylinders, a crank on the inner end of said connecting rod of thin ?at form connected at one‘e'nd to said crank. and awrist‘pin nxed inter mediate its ends in the outer end of the connect ing rod, one member having in one faceia recess of aslle and shape to rotatably receive the ends shaft. connecting rods between said pistons and face‘ of the other member. the inner member ing into said chamber, an outlet chamber and crank‘; said casing having an inlet passage open of said wrist pin. said recess being closed by one 10 having therethrough a slot at right angles to the first-‘named slot and through which the connect ing rod passes with freedom for articulating. movement. . an outlet ‘ passage leading out “of said central chamber through said'wall and terminating] with a port; a valve ,slidably and non-rotatably mounted on the outer end o'i'said shaft and seat 15 ing on said wall, said casing having Passages one for each cylinder each leading from the outer end. ' '5. In apparatus of the class described, having a ade up of inner and outer members. a piston packing between the ‘members. and means for clamping the members and packing d 7, , ‘ of its cylinder to and terminating with a port in said wall.;said valve having a chamber therein to connect the ?rst-named port ‘successively to together. and having a crankshaft and crank 20‘ the second-named ports and having a port lo therefor; a connecting rod of thin ?at form con cated outsidesaid chamber to successively con heated at one end to said crank. a wrist pin hav nect the second-named ports to the outlet cham- ‘ ing a relatively short central portion of non ber, said valve having above its chamber a cylin- ‘ clrcular cross section and relatively long cylin der opening at its upper end into the outlet cham drical portions one on each side thereof. said rod ber and having a partition, between the valve having in its outer end an opening therein to cylinder and said valve chamber having a rela rewive and closely fit the central portion of the tlveiy small fluid-conducting passage there wrist pin, the inner member having therethrough through. a piston in the valve cylinder and fired a slot through which the outer end of said rod to said shaft and subjected on its lower and passes. one member having in oneface a recess upper sides to inlet and outlet pressure‘ respec- ‘ of U-shaped cross section and at right angles to tively. and a bearing-for said shaft in said’ wall the slot in the inner member and closed by one adjacent said crank adapted to be engaged by said face of the other member ‘to rotatablyreceive the cylindrical ends of the wrist pin. 6. In apparatus of the class described, having crank and take the ‘upward thrust on said shaft. ‘ 9. In a ?uid meter, a ‘casing having a plurality of cylinders radiating from a central chamber. a plurality of pistons one in each cylinder, a crank members with a piston packing clamped there shaft mounted centrally in one wall of said between, a calibration stop adjustably mounted _ chamber with its axis at right angles to the axes in the outer end of the cylinder in the path of p of said cylinders, a crank on the inner end of 40 the piston. a crankshaft. and a crank therefor: ‘said shaft, connecting rods between said pistons a connecting rod in the form of a thin ?at strip and crank; said casing having an inlet passage having its inner end connected to said crank and opening ‘into said chamber. an outlet chamber having in its‘ outer end a non-circular opening. and an outlet passage leading out of said central and a wrist pin having a short central portion chamber through said wall and terminating with 45 fitted in said opening and relativelylong cylindri a cylinder. a piston made up of inner and outer cal portions~one on each side of said central; portion. said inner member having therethrough a port; a valve on the outer end of said shaft and seating on said wall, said casing having Pas sages one for each cylinder each leading from the a slot through which the outer end of- said rod outer end of its cylinder to and terminating with one member having in one face a U a port 'in said wall. said _Valve having a lower 50 shaped recess substantially equal in length to the chamber with upper and lower walls paralleling the wrist pin and closed by one “overall length of the first-named wall and openings in the lower face ofv the other member. said recess having a wall one to continuously register with the first ' width substantially the same as the diameter of named port and the other adapted to be succes the cylindrical portions of the wrist pin and a sively connected with the second-named ports. depth greater than such diameter. whereby to the fluid pressure acting on the upper wali'of the provide lost motion between the connecting rod lower chamber exceeding that acting on its lower and piston to enable the piston to be arrested by wall,» said valve having a port outside said cham said stop at various positions prior to the end ber to successively connect the second-named of the piston’s stroke. 7. In a ?uid meter, having a casing provided 60 ports to the outlet chamber, said valve having an upper chamber with upper and lower walls with a central chamber and a plurality of cylin generally paralleling the upper wall of the lower ders radiating therefrom and provided with in chamber but of greater area than the latter and let and outlet passages in opposite walls of said a relatively small passage connecting the upper chamber and passages leading from the outer and lower chambers. the upper wall of the upper 65 ends of said cylinders to and through said wall chamber being independent of the valve. whereby and terminating with ports surrounding said out let passage, 9. piston in each cylinder, a valve to control said passage and ports, connection: be‘ tween said pistons and valve to actuate the same, a valve in the inlet passage preventing the re turn ?ow from the chamber to the passage, said valve having a passage therethrough, and a pres sure relief valve normally closing the last-named passage but opening to permit ?ow therethrough the fluid pressure acting on it does not tend to unseat the valve. the fluid pressure force on the lower wall of the upper chamber being greater than that on the upper wall of the lower chamber. and connections from the upper wall of the upper chamber to the casing to transmit the ?uid pres sure thrust on the valve to said casing. WARREN H. DE LANCEY.