US2669129A - Multipressure totalizing device and adjustable fulcrum therefor - Google Patents

Description

Feb. 16, 1954 R. s. WILLIAMS MULTIPRESSURE TOTALIZING DEVICE AND ADJUSTABLE FULCRUM THEREFOR Filed April 20, 1951 W Q i INVENTOR. RAY S. WILLIAMS BY WQW xii-61s.

w 5% APWMU wh Z2? Patented Feb. 16, 1954 MULTIPRESSURE TOTALIZIN G DEVICE AND ADJUSTABLE FULCRUM THEREFOR Ray S. Williams, Orrville, Ohio, assignor to Hagan Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Application April 20, 1951, Serial No. 222,050

1 This invention relates to multipressure responsive devices of the adjustable ratio totalizbeam is always perpendicular, that is, at 90 to the axis of rotation of the fulcrum; and (3) the rotational component of the fulcrum is rigidly secured to the beam whereby the ratio of the lengths of the beam or lever arms on opposite sides of the fulcrum remains fixed for each ad justed position of the fulcrum.

The above and other objects of the invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which: I

Figure l is a top plan view of a multipressure device of the adjustable ratio totalizing type embodying a form of the invention;

Fig. 2 is a view in side elevation, partly in section, of the device; and

Fig. 3 is a view'in section taken on line III- III of Fig. 2.

In the drawings a multipressure responsive device l of the adjustable ratio totalizing type is shown that comprises frame members 2 and 3 having spacer blocks 4 and 5 between them at the ends thereof. The frame members andblocks are rigidly secured together as a unit by bolts 6, as shown. The device includes a beam 1 disposed between the frame members, and a doubleacting fulcrum 8 on which the beam is mounted.

Turning forces are applied to the beam at opposite sides of the fulcrum by a pluralityof pressure responsive input units 9, l9 and II, and a pressure responsive balancing and output unit l2. Units 9 and II! are secured to frame members 4 and 5, respectively, adjacent one end of beam 1 and units II and I2 are secured to members 4 and 5 adjacent the opposite end of the beam.

Units 9 and I9 exert opposing forces on the beam and are so placed with respect to the beam that those forces act at a distance L1 from the rotational axis of the fulcrum. Likewise, units H and 12 exert opposing forces on the beam and are so placed that those forces act at a 3 Claims. (01. 74-522) distance L2 fromthe rotational axis of the fulcrum. Devices 9, l0 and II are adapted to receive pressure inputs P1, P2 and P3. Unit I2 is provided with a valve [3 of such construction that a pressure P4 is established therein of such magnitude as to balance the algebraic sums of pressures P1, P2 and P3. Pressure P4 is also referred to herein as the output pressure, as that pressure may be transmitted to indicating devices, regulators, or other apparatus, as will be understood by those skilled in this art.

The fulcrum 8 is double-acting, is adjustable longitudinally of beam 1 whereby the lever arm lengths L1 and L2 may be adjusted with respect to each other, and embodies features of construction described infra.

' Units 9, I9 and II as illustrated, may be identical in construction, therefore, corresponding parts are given the same reference characters. Each of these units includes a bonnet [5 having an open side, a ring I 6 and a pressure deflectable member IT. The marginal edge of the diaphragm is clamped between the bonnet and the ring by stud bolts I9, these being also threaded into the frame member on which it is placed, to secure the unit thereto. The diaphragm may be of rubber, synthetic or natural, and reinforced, if necessary, and pre-shaped to provide a slack portion 20. The central portion of the diaphragm is clamped between the head 2| of a bolt and a clamp ring 22 by means of a nut 23 threaded on the bolt shank 24. The shank 24 extends through an aperture 25 in the frame member and is long enough to engage beam 1. As shown, the end of the shank extends into a bore 26 in the beam and is provided with a nut 21 that bears on the beam. By adjusting the position of nut 21 on the bolt shank, the central portion of the diaphragm I! may be moved up or down in the bonnet chamber to thereby adjust the effective area of the diaphragm. By that adjustment the areas of the respective diaphragms in units 9, l0 and H may be adjusted to equality with each other.

Unit l2 includes a bonnet 39 that is deeper than the bonnets 'of units 9, l9, and H in order to provide sufficient space to accommodate parts of valve l3, a ring 32 and a diaphragm 33. The marginal edge of diaphragm 33 is clamped between the bonnet and the ring by stud bolts 34' threaded into frame member 3. The diaphragm as shown is like the diaphragms of units 9, l0, and II.

The central portion of diaphragm 33 is clamped between bolt head 35 and a ring 36 by means of a nut 91 threaded on the bolt shank 38. The

end of the bolt shank extends into bore 26 and is provided with a nut 39 that bears on the beam. The position of that nut may be adjusted for the purpose above described, i. e., to adjust the effective area of diaphragm 33.

A bore 40 extends through the head and shank of the bolt as shown, and a side port 4|. in the shank vents the bore to the atmosphere. In the bolt head a tapered valve seat 42 is formed that is concentric with the bore 40. The bolt withits bore 40, port 4| and seat 42 forms a part of valve l3.

Valve |3 includes a valve stem 43- and abushing 44, the latter being threaded into the bonnet 3,0 and provided with an inlet port valve seat 45. One end of stem 43 is disposed to seat in valve seat 42. The opposite end of the stem is provided wth valve 46 disposed to seat-on valve seat 45. A coil spring 41 on the stem 43 and confined between a flange 48 secured to the stem biases the stem in a direction for seating valve 46 on the inlet port seat 43: The outer end of bushing 44 is designed tobe coupled to a supply pipe to which a source of supply of compressed air of constant pressure, is connected.

When a force is applied to diaphragm 33 in such direction as to move the central portion of the diaphragm into the bonnet, the exhaust seat in the bolt head 35 movesthestem in a direction to unseat valve 46 from the inlet port seat 45. While the inlet port is uncovered, compressed air passes into the chamber of the bonnet until the pressure P4 therein has increased to such a value that it exertsga force sufiicient to deflect the diaphragm in the opposite direction until valve 46 reseats on and closes the inlet port seat of the valve. If the original force has not changed in value, the opposing force produced by the-pressure will balance the former when the inlet port is closed. At balance the exhaust port 42 is closed by the valve stem.

If the balancing pressure P4 does not change but the original force decreases, the force of pressure P4 on the diaphragm causes the dia-v phragm to move outwardly, whereby the exhaust portseat 42 is uncovered. Air is then discharged. to the atmosphere until pressure P4 decreases the force on the diaphragm to. a value equal to.

the opposing force applied through beam 1-. When that balance occurs, the exhaust seat is reclosed by the stem. The balancing pressure trapped in the bonnet so long as the exhaustv and inlet ports are. closed.

Ifthe diaphragms ofunitsifi, [0,11 and, l 2ghave equal effective areas and if'these areas are as:

sumed to be unit areas, say, 1 sq. in., and that;

pressure P1, P2 and P3 (in p. s. i.), are-applied to the diaphragm, of those units the value of hal ancingpressurePi is equal. to

grPwPi) Ht When the diaphragm areas are unit areas the values of the pressures P1, P2, P3 andBi areegual to the forces exerted by the diapihragms on beam I.

- 4 Since L L2 is constant for any setting of the fulcrum 8, P4=K(P1P2) +P3 Fulcrum 8' comprises a yoke having a loop 49 that embraces beam I, and journals 50 and 5| that extend outwardly from opposite sides of the loop. The fulcrum includes anti-friction bearings 52 and 53}, which the journals 50 and 5| are mounted. The anti-friction bearings, as illustrated, are ball bearings, the outer races of which are secured to supports 54 and 55. As

shown, thes pportjs 54 and 55 have bores 56 and 51 that are concentric with the journals.

The outer "ends of supports 54 and 55 are provided with flanges 58 and 59, respectively, that abut the sides of the frame members 2 and 3. The supports 54 and 55 are releasably secured to the frame members 2-and 3 by m'eansof clamp bolts 60 and 6| that extend into the supports" from opposite sides of the frame members 2 and 3, as shown. Clamp bolt 6|) passes through a bore in'support 54- and is threaded into the inner end of support 55. Clamp bolt6| passes through a bore in support 55 and is threaded intothe inner end of support 54.

The shape of the loop 49' and the shape oft-he beam in transverse section'may'beof any desired form. As illustrated, the transverse section of beam 1 is rectangular. The depth of the beam is greaterthan its width so that the. major and, the minor axes of any transverse section extend vertically and horizontally, respectively. The longitudinal axis of'the beam isina plane con-- taining the minor axisof any transverse section, of the beam.

The shape of the loop 49 is preferably made to conform to the shape of the transverse section of beam 1. The journals are so located onthe loop that the rotational axis of journals pass through the intersection of the major and minor axes of any section of the 'beam, as shown.

The yoke loop 49 is releasably secured to the beam by means of a bolt 63;, Asfshown, this bolt is threaded throughjournal 5|- so that its inner end engages aside of beam 1. The side of "the beam that is engaged by the end of bolt 63- is provided with a slot 6.5 that extends longitudinalwise ofythe beam 1' in either direction whereby.

the len ths of the lever arms In and L2 may be adjusted in accordance with the ratio constant required v to producea given operating characteristicof the device I. When it is desired to adjust the position of thefulcrum, bolts. 6 6| and-63, are loosened to unclampbeam I from the yoke and torelease flanges 58 59from thesides 0t theframemembers 2 and .3. The fulcrummay then be moved as a; unit toward either end. of thetbeam; When it has been adjusted to theproper position, the bolts are tightenedwhereby the fulcrum, supports are clamped to the frame members-2 ,and.3-and beam 'I.-is clampedto yoke 9 ,9

Inithe form-of yoke described, the. rotational axis-0f the journals; is always-on center with the I 7 ent r-li e o m IAISOI he, eneimdin l center line of beam 1 is always at a fixed and constant distance from the exhaust port seat 42 of pressure balancing and output unit 12. Therefore, the output and balancing pressures established in unit I2 will always be proportional to the forces acting on beam 1 whether those forces act in one direction or the other on the fulcrum. By means of the fulcrum construction described and illustrated, the totalizing device I may be mounted in a horizontal position as shown in Fig. 2, or it may be mounted in a vertical position, or the device may be inverted with reference to the position shown in Fig. 2 and mounted horizontally.

The device i may be put to many uses, some of which are illustrated in the co-pending applications of Alfred A. Markson, serially numbered 158,278 filed April 26, 1950; 156,986 filed April 20, 1950, now Patent No. 2,631,599 issued March 17, 1953; and 157,272 filed April 21, 1950, all assigned to Hagan Corporation, Pittsburgh, Pennsylvania.

Having thus described the invention, it will be apparent to those skilled in this art, that the illustrated embodiment of the invention is subject to modification without departing from either the spirit or the scope of the invention.

Therefore, what is claimed as new and desired to be secured by Letters Patent is:

1. In a multipressure responsive device having spaced frame members, a beam between the frame members, a fulcrum for the beam secured to the frame members, pairs of housings on the frame members on opposite sides of the fulcrum, each housing having a pressure deflectable member connected to exert a force on the beam, diaphragms on each side of the fulcrum acting oppositely to each other and at the same distance from the fulcrum, said fulcrum comprising a yoke embracing the beam and slidable on the same, said yoke having journals extending outwardly from opposite sides of the beam, an antifriction bearing for each journal, a support for each bearing disposed between said frame members and having flanges engaging the same, means for releasably securing the yoke to the beam and means for releasably securing the bearing members to said frame members whereby the fulcrum may be moved along the beam to one side or the other of the mid-point between the lines of action.

of the pairs of pressure deflectable members on said beam.

2. A device as set forth in claim 1, characterized by the fact that means are provided for so securing the beam to the yoke that the axes of rotation of said journals pass through the point of intersection of the major and minor axes of the beam at any section transversely of the beam.

3. A pressure totalizing device comprising a frame having spaced frame members, a beam located between the members, a fulcrum secured to said frame members and said beam, pairs of pressure actuated force developing members on said frame members, said members being so arranged thereon as to form opposing couples acting on the beam at opposite sides of the fulcrum, each member of a couple acting on the beam at equal distances from the fulcrum, said fulcrum comprising a yoke having a loop slidable along and embracing said beam, said yoke having journals projecting outwardly from opposite sides thereof, the longitudinal axes of said journals being colinear and passing through a plane disposed at right angles to the line of action of said couples and containing the major axis of the beam, an anti-friction bearing on each journal, means for releasably securing the yoke to the beam and a support member for each bearing releasably secured to said frame members, said support members being movable as a unit with said yoke journals and bearings along said beam whereby the lever arms between said pairs of couples and the fulcrum may be adjusted relative to one another.

RAY S. WILLIAMS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date Re. 19,745 Baselt Nov. 5, 1935 856,784 Kolstram June 11, 1907 1,587,522 Hedgecock June 8, 1926 1,780,713 McEwan Nov. 4, 1930 2,078,106 Temple Apr. 20, 1937 2,127,863 Kilkemeier Aug. 23, 1938 2,136,454 Miller Nov. 15, 1938, 2,231,696 Wolfe Feb. 11, 1941

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