US2099244A - Lever - Google Patents

Description

NO v. 16, 1937. P. C TEMPLE 2,099,244

' LEVER Filed Sept. 2l, 1954 Y; 6 z 6 2 64- I *67 I L7 60 3432 /.9 l Il' 5 6754 Il. Illllll lll' Z Z3 l 37 e/ .f ,A /4 J 1 l a9 /fl 7 3 8/ a 53' 49 6] 2/ Z737" 5 if" '46 Zv 7 v 40 47 6/ 4L- d 73 4J PAUL C. l' 7MP4E heated Nvv- 1e, 1931 t 'I sTArEsrATENT 2,099,244 j nur c. Temple, pagina nl., assigner u A..w. Cash Company, Decatur, Ill.,'a corporation of Delaware l Application september zi, 1934, serial Nn. *144,948 w 4 claims. (ci. 'i4-41o) n Y This invention relates to levers, vand more particularly to a lever suitable for transmitting movement fromv an automatic control' device. such as a pressure responsive diaphragm, to a ilow controlling valve. This application is a continuation in part oi.' my prior application Serial No. 646,835, illed December 1K2, 1932, now Patent No. 1,992,048, granted February 19, 1935. y

Ii the force transmitted by the lever in'an apparatus of this type materially ,exceeds that necessary to eilect .the desired movement of the valve. there is danger of overloading some part of the mechanism and causing serious damage thereto. The valve may be of the seating type, I and if lt is'jammed too tightly against its seat one or both oi' these parts will be injured, and the operation will be rendered unsatisfactory.

It is accordingly one 4object oi' the invention to provide a simple, inexpensive and compact lever which will yield upon application of an excessive force thereto. It is a further object of the invention to provide an improved and compact construction for a lever which will yield upon application of an excessive torce thereto in any direction.

With these and other objects in view, as will be apparent to those skilled in the art, the lnvention resides in the ycombination of parts set forth in the speciication and covered by the claims appended hereto.

Referring to the drawing illustrating one embodiment of the invention, 'and in which like reference numerals indicate like parts,

. Fig. 1 is a vertical section through the center of an automatic controller;

Fig. 2 is an enlarged view of a portion of Fig. 1, showing the lever in its flexed position; and

Fig. 3 is a section on the line 3-3 of Fig. 1.

'I'he embodiment illustrated comprises a hollow valve body or caslngll) divided internally by suitable partitions into an inlet chamber Ii, an

A outlet or exhaust chamber i2, and two intermediate chambers I4 and I5. 'I'he exhaust chamber is located between the intermediate chambers, and the inlet chamber is U-shaped and arranged with its end portions adjacent to the intermediate chambers. An inlet opening i6 leads dlrectly into the inlet chamber I I, and an exhaust opening Il leads directly from the exhaust chamber I2. Similar openings (not shown) communicate directly with the intermediate chambers I4 and II.

Inlet ports orpassages i9 and 2li connect the inlet chamber with the intermediate chambers Il and I5 respectively, and exhaust ports or passages 2l and 22 connect'the exhaust chamber with the intermediate chambers I4 and i5 respectively. In the preferred construction these ports i9, 20, 2l and 22 are arranged in direct axial alignment.

5 The ow of iluid through the casing I0 is conlong enough to hold the valves slightly om the 15 exhaust seats when the stem is in its central or f neutral position. This is particularly desirable rwhenthe valve stem is arranged to be actuated by an automatic pressure responsive device, since it removes a large part of the unbalancedload sensitive. However, if the fluid to be controlled is a gas, such as compressed air, the valve'ports can be made much smaller and the unbalanced load will thereforebecome of little importance. In such a case the valve stem is preferably made slightly shorter. so that both valves will close against the exhaust seats whenthe valve stem is in its neutral position. This prevents any loss of iuid to the exhaust so long as ,the valve stem remains in this position. It will be understood that the valve stem is not fastened to the ball valves, but merely pushes against them. Hence any inaccuracy or misalignment which may occur in the actual construction will not prevent 35 the valves from seating tightly.

In order that my improved four-way valve mechanism may be conveniently manufactured and assembled, I prefer to form the various inlet and exhaust portsin separate parts which are removably mounted in the. casing lll. As illustrated, the exhaust ports 2| and 22 are formed in flanged hollow cylindrical members 21 and 28 respectively which are held rmly in position by means of plugs 29 and 30 screw-threaded to the casing I0. The plugs 29 and 30 are arranged in direct axial alignment with the members 21 and 29. The inlet ports I 9 and 20 are formed in ilanged cylindrical members 32 and 33 which are screw-threaded to the interior bore of the members-2l and 28. The plugs 29 and 30 are recessed axially as shown at 34 to clear the iianged ends of the inlet seat members 32 ,and 33, and radial openings 35 are provided to communicate with the recesses so that the fluid 55 Thesevalve's are con- 10 on the valves and `makes the controller ,more 2 0 ilow to the inlet ports will not be obstructed. Radial openings 31 are provided in the exhaust seat members 21 and 28 to establish communication between the interior of these members and the adjacent intermediate chambers.

It will now be seen that if fluid is supplied under pressure to the inlet chamber Il, and the valve stem 25 is moved upwardly, valve 23 will close the inlet port I 9. At the same time, the uid pressure will force valve 24 upwardly to close the exhaust port 22. Fluid can therefore ow from the inlet chamber Il to the intermediate chamber I5, and iluid can also flow from the intermediate chamber I4 to the exhaust chamber I2. If the valve stem is moved downwardly to its other extreme position, the inlet chamber will be connected with the intermediate chamber I4, and the intermediate chamber I will be connected with the exhaust chamber.

In the construction illustrated, the valve stem 25 is arranged to be actuated automatically by means of a fluid pressure responsive diaphragm 39 which is connected to the valve stem by means of a lever 40 of the rst class. This lever is pivotally supported by means of a small flexible diaphragm 4I which serves both as a fulcrum for the lever and as one wall of the exhaust chamber I2. This diaphragm 4I is preferably formed from a thin fiat plate of a suitable material, such as phosphor bronze, and it is clamped at its periphery between the valve casing I Il and a diaphragm casing 43, these parts being suitably fastened together. 'I'he intermediate portion of the valve stem 25 is enlarged and provided with a transverse opening 44 to receive the spherical end 45 of the short arm oi' the lever 40. 'I'he other end 41l of the lever, which is also preferably spherical, is positioned within a transverse opening 46 (preferably rectangular in cross-section) formed in a blockV 49 which is secured to the central portion of a lower pressure plate 5I. 'I'he central portion of the main diaphragm 39 is clamped between the lower pressure plate 5| and an upper pressure plate 52. these plates being fastened together by a'central stud 53 threaded into the block 49 and provided with a nut 54 at its upper end. The main diaphragm is clamped at its periphery between the diaphragm casing 43 and a flanged upper cover plate 56 which is fastened to the casing 43.

It will now be seen that the main diaphragm 39 divides the space enclosed by the casing 43 and the cover plate 56 into an upper chamber 51 and a lower chamber 58. 'I'he cover plate 56 is provided with an openingy 60 leading to the chamber 51,

and the casing 43 is provided with an opening 6I leading to the chamber 58. These openings are shown screw-threaded for convenience in connecting `pipes thereto. A controlling fluid pressure may be applied to either or both of these chambers, f

In order to support the main diaphragm against the controlling fluid pressure, I have shown a coiled tension spring 63 arranged in a vertical position above the center of the diaphragm with its lower end connected to the stud 53. The upper end of the spring is fastened to a nut 64 which is mounted on a vertical screw 65. This screw is rotatably supported in a housing 61.which is fastened to the cover plate 56, andv which servesto enclose the spring. The upper end ofthe screw 65 extends through a stufng box '68 at the top of the housing 61, so that the screw can be rotated to move the nut 64 l.-vertically and thus vary the tension of the spring.

'I'he controlling uid pressure to which the seat. The joint will provide the main diaphragm is subjected may become large enough to cause an excessive load on the valve seats or fulcrum diaphragm. In order to prevent such excessive loading, I form the valve operating lever 40 with a flexible joint which is normally held rigid by a yieldable device.

In thepreferred construction illustrated the short arm of the lever is provided with an hexagonal portion forming a shoulder, and an externally screw-threaded stud 1I which extends through the fulcrum diaphragm 4I. A small annular gasket 12 surrounds the stud 1I between the shoulder 10 and the diaphragm, and these parts are clamped rmly together by means of a flanged member 14 threaded to the stud. A flanged member is screw-threaded to the adjacent end of the long arm of the lever, and the two members 14 and 15 provide plane cooperating surfaces which are perpendicular to the axis of the lever. These surfaces are normally held in contact by means of a coiled compression spring 'I6 surrounding the member 15. 'I'he spring 16 is supported by means of an annular cap or collar 13 screw-threaded to a cylindrical shell 19 integral with the ange 14. 'I'he shell 19 surrounds A the member 15 and the spring 16. The cap 13 is provided with a central opening considerably larger than the portion o1' the lever extending therethrough, so that the cap will permit a substantial lateral pivotal displacement of one part of the lever relative to the other.

In order to maintain the correct augment between the two parts of the lever, I provide them with intertting portions which are nevertheless so shaped as to allow the desired flexing when necessary. For this purpose the end of the stud 1.I is formed with a spherical projection 8| which ts closely within a centrally located cylindrical opening 62 in the flanged member 15.

The operation of the invention will now be apparent from the above disclosure. The diaphragm 36 moves in response to any change in the eifective pressure thereon, and these movements are transmitted through the lever 46 and valve stem to the ball valves 23 and 24. These valves control the admission of uid from the inlet chamber II to the intermediate chambers I4 and I5, thus controlling the pressure in these chambers. This pressure may be used to move a double-acting piston in a power cylinder (not shown). In case the eifective pressure on the diaphragm 39 materially exceeds that necessary to close either of the ball valves, the joint in the lever 40 will ex against the pressure of the spring 16, one part of the lever tipping laterally relative to the other part, as shown in Fig. .2, thus allowing the diaphragm to continue its movement without causing excessive pressure betweenA the. valve and its desired protection irrespective of the direction in which the excessive force is applied. Upon restoration of normal conditions, the spring 16 will expand and hold the flanged member 15 in contact with the member 14. The spherical projection 8| will prevent relative sliding movement between the contacting surfaces of the two parts of the lever, thus avoiding the undesirable eiect which such movement would have upon the adjustment oi' the controller. The construction is simple and inexpensive to manufacture, and it is so compact and self-contained that it may be readily applied to any controller of th type havin! a Valve-861511' ating lever.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A lever formed in two parts located in substantial alignment and shaped to provide plane cooperating surfaces perpendicular to the axis of the lever, a coiled compression spring surrounding one part of the lever and tending to maintain said surfaces in contact, and supporting means for the spring carried by the other part of the lever and shaped to permit a substantial lateral tipping of one part of the lever relative to the other, whereby the lever will yield upon application of an excessive force thereto.

2. A lever formed in two parts, each part of the lever having a flange thereon, a coiled compression spring surrounding one part of the lever and tending to maintain the corresponding llange in contact with the other flange, and an annular cap carried by the said other flange and arranged to support the spring, the cap having a central opening through which one of the lever parts extends and considerably larger than said lever part, whereby one lever part may be laterally displaced pivotally relative to the other part through a substantial angle.

3. A lever formed in two parts located in substantial alignment and shaped to provide plane cooperating surfaces perpendicular to the axis of the lever, one of said parts having a recess therein and the other part having a projection positioned within the recess to prevent relative sliding movement between said surfaces while a1- lowing lateral tipping of one lever part relative to the other, and a coiled compression spring surrounding one part of the lever and tending to maintain said surfaces in contact, whereby the lever will yield upon application of an excessive force thereto.

4. A lever formed in two parts located in substantial alignment and shaped to provide plane cooperating surfaces perpendicular to the axis of the lever, one of said parts having a cylindrical recess therein and the other part having .a spherical projection positioned within said recess, and a yieldable device tending to maintain the said surfaces in contact.

PAUL C. TEMPLE.

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