US3262374A

US3262374A - Pneumatic timing device

Info

Publication number: US3262374A
Application number: US370407A
Authority: US
Inventors: Sam S Trombatore; Wilbur J Bradtke; William J Griswold
Original assignee: Webcor Inc
Current assignee: Webcor Inc
Priority date: 1964-05-27
Filing date: 1964-05-27
Publication date: 1966-07-26
Anticipated expiration: 1983-07-26

Description

y 1966 s. s. TROMBATORE ETAL 3,262,374

PNEUMATIC TIMING DEVICE Filed May 2'7, 1964 FIG. 1

I N VE N TORS Sam 5. Wombaiora Wilbur J Bradtkc W2 ll 1%; J. Griswold,

United States Patent 3,262,374 PNEUMATIC TIMING DEVICE Sam S. Trombatore, Des Plaines, Wilbur J. Bradtke, Park Ridge Manor, and William J. Griswold, Bridgeview, Ill., assignors to Webcor, Inc., Chicago, 11]., a corporation of Illinois Filed May 27, 1964, Ser. No. 370,407 10 Claims. (Cl. 9216) This invention relates to a pneumatic timing device.

One of the objects of this invention'is the provision of a timing device including a moveable ram which at the end of a predetermined interval is operttive to per form a desired function.

Another object of this invention is the provision of a pneumatic timing device which at the end of a predetermined interval is operable to discharge a burst of pressure fluid for use as a propelling or actuating force or for pressurizing purposes.

A further object of this invention is the provision in a pneumatic timing device of means for varying the timing interval.

Still a further object of this invention is the provision of means in a pneumatic timing device for selectively rendering the same operative or inoperative.

Still a further object of this invention is the provision of novel means for releasably locking a moveable ram against movement.

Other and further objects and advantages of this invention will become apparent from the following description when the same is considered in connection with the accompanying drawings in which,

FIG. Us a side elevational view of a pneumatic timing device in accordance with our invention;

FIGS. 2 and 3 are left and right hand end elevational views respectively;

FIG. 4 is a cross-sectional view taken substantially on .line 44 of FIG. 3;

FIG. 5 is a cross-sectional view taken substantially on line 55 of FIG. 3, with the parts in a different operative position and with certain parts rotated and others eliminated for greater clarity.

FIGS. 6 and 7 are views similar to FIG. 5, but showing the parts in different stages of operation and with certainof the parts rotated for greater clarity.

FIG. 8 is a cross-sectional View taken substantially on line 8-8 of FIG. 4;

FIG. 9 is a cross-sectional view taken substantially on line 99 of FIG. 4;

FIG. 10 is a view similar to FIG. 8 but showing the parts in a different operative position.

Referring to the drawings, the numeral indicates a casing or-body having a cylindrical chamber or bore 16. At the rearward end of the casing 15 the bore 16 is reduced in diameter to provide an annular shoulder 17. The reduced diameter portion of the bore is provided with an annular groove in which is received a resilient O-ring sealing member 18. The wall of the casing 15 is drilled and tapped at spaced points to afford connections as at 19 and 21 to conduits connected to a source of pneumatic pressure fluid. An end member 22 provided with an annular flange 23 is received within the reduced diameter portion of the bore with the flange 23 abutting against the shoulder 17 and with O-ring 18 in sealing engagement with the cylindrical surface of end member 22. End member 22 is provided with an axial bore 24 and with a counter-bored aperture 26 which is disposed eccentric to the bore 24. A stud 27 preferably threaded at bothends is provided with an intermediate flange 28 and passes through the counter-bored aperture 26 with the flange received in the counter-bore of the aperture An O-ring 29 circumposed about the stud adjacent the flange affords a seal between the stud 27 and the aperture 26. One end of stud 27 extends outwardly of end member 22 and is arranged to engage with a lock nut 31 which affords means for rotating the stud, for a purpose as will be hereinafter explained.

An end member 32 provided with a stepped cylindrical surface cooperates with the opposite end of the casing 15, in the manner illustrated. Said end'member is secured to the casing 15 by a plurality'of circumferentially spaced bolts 33 which pass through apertures in the end member and engage in correspondingly threaded openings in the wall of the casing. End member 32 is provided with an annular recess in which is received an O-ring 34 affording a fluid tight seal between the end member and the casing 15. The end member also is provided with an axial bore 36 which is lannularly grooved to receive an O-ring 37.

A ram 38 shaped substantially as illustrated includes a cylindrical main body portion 39 and an end portion 41 of reduced diameter providing an annular'shoulder 40. An annular groove 42 is provided in the main body portion 39 and a similar groove 43 is provided in the red-uced portion 41 to receive an O-ring 44 which affords a liquid tight seal between end member 22 and the ram at one end, while the O-ring 37 affords a corresponding seal between end member 32 and the ram at the opposite end of the casing. The ram 38 is axially slideable relative to the casing.

A disk-type piston 46 is provided with a central bore to receive the ram 38 and is provided with inner and outer annular grooves in which are received O-rings 47 and 48 alfording fluid tight seals between the casing 15 and piston 46 and the ram 38 and the piston. The piston 46 is axially slideable relative to the ram 38, as will be hereinafter explained.

Referring to FIG. 4, the piston 46 is provided with a bleed aperture and valve seat 49 and carries a cooperat-' ing threaded valve stem51 for adjusting the flow of fluid through the aperture. A coiled spring 52 circumposed about the ram 38 is interposed between the piston 46 and the end member 22 and normally tends to urge the piston in a direction towards the left, as viewed in FIG. 4.

As will be apparent by reference to FIG. 4 the ram 38 permanently is restricted against movement to the right by reason of the annular shoulder 40 abutting against end member 22. In the course of operation of the device of our invention, the ram 38 is restricted against movement to the left, as viewed in FIG. 4, by a locking or latching means which comprises a pair of generally cylindrical rod members 53 disposed at diametrically opposed points on the ram, with the medial portion of each rod member being machined or cut away substantially to a diametral line as illustrated clearly in FIG. 8. The rod members 53 are received in the annular groove 42 with the flat faces of the machined areas engaging against the bottom of the annular groove. A pair of coiled springs 54 are disposed at opposite ends of the rod members and serve to draw the rod members in a direction towards each other so as to insure seating of each rod member Within the groove. Annular recesses are provided in the ends of the rod members to retain the end loops of the springs 53 so as to prevent inadvertent displacement of the same. Anchored in each rod member53 is a pin 56 which is angularly disposed in relation to the plane of the flat face of the machined portion so that the pins 56 assume the angular relationship substantially as illustrated in FIG. 4. It will be understood that the springs 54 afford sufficient tension to maintain the rod members 53 within the annular groove 42 in the relationship illustrated in FIGS. 4 and 8 and when so disposed the rod members afford a lock or abutment to prevent the ram 38 from moving to the left, as viewed in FIG. 4. However, the rod members 53 may be displaced from the groove, as will be- 3 hereinafter explained, to permit the ram 38 to move to the left, as illustrated in FIG. 7.

The piston 46 is provided with a threaded aperture 57 which is arranged in registration with the stud 27 so that the stud may engage within the aperture, in the manner illustrated in FIG. 4, to retain the piston in inoperative position against movement axially of the ram.

In order to effect operation of our invention the stud 27 is caused to be rotated approximately one-'quarter of a turn in a direction to effect disengagement of the threaded end of the stud from the threaded aperture 57 in the piston 46. In inoperative position the ram 38 is locked against movement to the left, as viewed in FIG. 4, by the rod members 53. Assuming that both threaded

openings

19 and 21 are connected to a common pressure line, and that the pressures on both sides of the piston 46 in chamber 16 are equal, it will be seen that pressure fluid is acting on annular shoulder 40 tending to urge ram 38 to the left, as viewed in FIG. 4. After the piston I is freed for movement as in FIG. 5, the pressure of the spring 52 against the piston 46 will cause the same to move towards the left. The rate of movement of the piston will be determined by the adjustment of the bleed aperture 49 which permits pressure fluid to pass from the chamber adjacent the leading face of the piston to the chamber adjacent the trailing face of the piston. It will be apparent that upon rotation of the threaded stem 51 an adjustment of the bleed aperture will be effected. The piston 46 will continue to move to the left under the influence of the spring 52 to a point where the piston engages the pins 56 and upon such engagement effects a rocking of the rod members 53 from the locking position illustrated in FIG. to the position illustrated in FIG. 6. In this latter position the right shoulder edge 42a of the annular groove 42 is caused to engage the flat faces of the rod members 53 and by reason of the constant pressure on the annular shoulder 40 the shoulder edge 42a effects a camming action on the rod members 53 to cam the same out of the groove 42 thereby to release the ram so that it may continue to move to the left in the direction of the arrow indicated in FIG. 7. It will be apparent that when the annular groove 42 moves to a point where it is in registration with the groove of O-ring 37 the chamber adjacent the leading face of the piston, in effect, is opened to the atmosphere so that the pressure differential acting on the ram 38 in a direction to move the ram to the left is substantially increased resulting in a very rapid movement to the ram to effect a desired rapid actuation of any device or apparatus. Also, when the ram 38 in its movement reaches a position wherein the O-ring 44 is caused to move out of the bore 24 of the end member 22, the pressure fluid within chamber 16 on the trailing side of piston 46 is discharged as a blast through bore 24 for pressurizing or propelling purposes.

It will be understood that if desired the ram may be completely ejected from the casing or may be limited in its movement by engaging against an 'abuttment or an element to be actuated.

It will be understood that the device of our invention may also be utilized in applications involving normal ambient pressures. In such cases it is preferred that the ram 38 be biased by a spring not shown abutting the rearward or right hand end of the ram to take the place of pressure fluid for urging the ram in a direction as indicated by the arrow in FIG. 7. As in the first described embodiment, the piston 46 will move axially of the ram, from the right to the left, under the influence of the spring 52 and the rate of movement will be controlled by the adjustment of the bleed aperture 49. Of course, under the last mentioned conditions of operation, no pressurized fluid is available in the chamber adjacent the trailing face of the piston for discharge as a blast or burst through the bore of the end member.

The terms air and pneumatic as used herein are intended to cover air as well as any other gas.

Various changes coming within the spirit of our invention may suggest themselves to those skilled in the art; hence we do not wish to be limited to the specific embodiments shown and described or uses mentioned, but intend the same to be merely exemplary, the scope of our invention being limited only by the appended claims.

We claim:

1. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and provided with end walls, each having a central bore,

(b) a piston having a central bore and being moveable within said chamber, all of said bores being disposed in axial registration, 7

(c) a ram slideably mounted in all of said bores,

((1) means biasing said piston in one direction,

(e) means in said piston for bleeding air from the chamber portion adjacent the leading face of the piston to the chamber portion adjacent the trailing face of the piston to control the rate of travel of said piston,

(f) said ram having an annular groove,

(g) releasable latching means within said chamber effective to lock said ram against movement,

(h) said latching means including a pair of oppositely disposed rod members arranged to be received in said annular groove and to extend transversely of said ram to lock said ram against movement, and

(i) resilient means biasing said rod members into said groove,

' (j) each of said rod members having a flat camming surface and a projection extending in angular relation to the plane of said surface and to the axis of said ram,

(k) said projections being arranged to be engaged by said piston whereby said rod members are cammed out of said groove to release said ram for movement.

2. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and provided with end Walls each having a central bore,

(b) a piston having a central bore and being moveable within said chamber, all of said bores being disposed in axial registration,

(c) said body having inlet ports arranged to admit pressure fluid into said chamber on opposite faces of said piston,

(d) a ram having a first cylindrical portion and a second cylindrical portion, the latter being smaller in diameter than the former,

(e) said first cylindrical portion being slideably received in the bore of the piston and in the bore of one end wall,

(f) said second cylindrical portion being slideably received in the bore of the other end wall,

(g) the differential area at the juncture of said first and second cylindrical portions of said ram affording an annular surface on which pressure fluid may act to bias the ram in one direction,

(h) spring means circumposed about said ram and biasing said piston in one direction,

(i) means in said piston for bleeding pressure fluid from the chamber portion adjacent the leading face of the piston to the chamber portion adjacent the trailing face of the piston to control the rate of travel of said piston, and

(j) releasable latching means within said chamber effective to lock said ram against movement,

(k) said piston being arranged to move into engage- ,(c) said body having inlet ports arranged to admit pressure fluid into said chamber on opposite faces of said piston,

4 (d) a ram having a first cylindrical portion and a second cylindrical portion, the latter being smaller in diameter than the former,

(c) said first cylindrical portion being slideably receivedin the bore of the piston and in the bore of one end wall,

(j) said ram having an annular groove in said first cylindrical portion,

(k) releasable latching means within said chamber effective to lock said ram against movement,

(1) said latching means including a pair of oppositely disposed rod members arranged tobe received in said annular groove and to extend transversely of said ram to lock said ram against movement, and

(m) resilient means biasing said rod members into said groove,

(11) each of said rod members having a flat camming surface and a projection extending in angular relation to the plane of said surface and to the axis of said ram,

() said projections being arranged to be engaged by said piston whereby said rod members are cammed out of said groove to release said ram for movement under the influence of pressure fluid.

4. A pneumatic timing device comprising,

(a) a body having a cylindrical chamber and providedv with end walls each having a central bore,

(0) said body having inlet ports arranged to admit pressure fluid into said chamber on opposite faces of said piston,

(g) the differential area at the juncture of said first and second cylindrical portions of said ram affording an annular surface on which pressure fluid may act to bias the ram in one direction, t

(j) said ram having a pair of diametrically opposed groove portions,

(k) abutment means arranged to be received in said groove portions and to lock said ram against axial movement in said one direction, and

(1) means associated with said abutment means and arranged to be engaged by said piston whereby said abutment means is'cammed' out of said groove and said ram is released for axial movement.

5. In combination,

(-21) a ram supported in bearings for axial sliding movement and having oppositely disposed groove portions,

(b) a member slideably supported on said ram,

-(c) means biasing said member in one direction,

(d) means controlling the rate of movement of said member relative to said ram,

(e) releasable latching means effective to lock said ram against movement,

(-f) said latching means including a pair of oppositely disposed rod members arranged to be received in said groove portions and to extend transversely of said ram to lock said ram against movement, and

(g) resilient means biasing said elements into said groove portions,

(h) each of said rod members having a flat camming surface and a projection extending in angular relation to the plane of said surface and to the axis of said ram,

(i) said projections being arranged to be engaged by said piston whereby said rod members are cammed out of said groove portions to release said ram for movement. 6. The invention as defined in claim 1 in which the ram is pressure biased in the same direction as the piston.

7. The invention as defined in claim 5 in which the ram is pressure biased in the same direction as the piston.

8. A pneumatic timing device comprising,

(b) 'a piston having a central bore and being movable Within said chamber, all of said bores being disposed in axial registration,

(c) said first cylindrical portion being slideably received in the bore of the piston and in the bore of one end wall,

' (j) releasable latching means within said chamber effcctive to lock said ram against movement,

(k) said piston being arranged to move into engagement with said latching means thereby to release said r-am for movement under the influence of pressure fluid,

(l) the movement of said ram opening a passage in the bore of the other end wall to permit discharge through said passage of pressure fluid from the chamber portion adjacent the trailing face of the piston.

9. A pneumatic timing device comprising,

(b) a piston having a central bore and being movable within said chamber, all of said bores being disposed in axial registration,

() said body having inlet ports arranged to admitv pressure fluid into said chamber on opposite faces of said piston,

(6) said first cylindrical portion being slideably received in the bore of the piston and in the bore of one end wall,

(i) means in said piston for bleeding pressure fluid from the chamber portion adjacent the leading face of the piston to the chamber portion adjacent the trailing face of the piston to control the rate of travel :of said piston, and

(j) said ram having an annular groove in said first cylindrical portion,

(I) said latching means including a pair of oppositely disposed rod members arranged to be received in said annular groove and to extend transversely of said ram to lock said ram against movement, and

(m) resilient means biasing said rod members into said groove,

(0) said projections being arranged to be engaged by said piston whereby said rod members are cammed out of said groove to release said rain for movement under the influence of pressure fluid,

(p) the movement of said ram opening a passage in the bore of the other end wall to permit discharge through said passage of pressure fluid from the chamber portion adjacent the trailing face of the piston.

10. The invention as defined in claim 3 in Which re leasable means are provided for securing the piston against movement.

References Cited by the Examiner UNITED STATES PATENTS 2,677,417 5/1954 Logan et a1 92l30 2,693,852 11/1954 Corbett 251-49 3,020,094 2/1962 Murty et al 188170 3,188,922 6/1965 Cruse 9263 EDGAR W. GEOGHEGAN, Primary Examiner.

SAMUEL LEVINE, Examiner.

I. C. COHEN, Assistant Examiner.

Claims

1. A PNEUMATIC TIMING DEVICE COMPRISING, (A) A BODY HAVING A CYLINDRICAL CHAMBER AND PROVIDED WITH END WALL, EACH HAVING A CENTRAL BORE, (B) A PISTON HAVING A CENTRAL BORE AND BEING MOVEABLE WITHIN SAID CHAMBER, ALL OF SAID BORES BEING DISPOSED IN AXIAL REGISTRATION, (C) A RAM SLIDEABLY MOUNTED IN ALL OF SAID BORES, (D) MEANS BIASING SAID PISTON IN ONE DIRECTION, (E) MEANS IN SAID PISTON FOR BLEEDING AIR FROM THE CHAMBER PORTION ADJACENT THE LEADING FACE OF THE PISTON TO THE CHAMBER PORTION ADJACENT THE TRAILING FACE OF THE PISTON TO CONTROL THE RATE OF TRAVEL OF SAID PISTON, (F) SAID RAM HAVING AN ANNULAR GROOVE, (G) RELEASABLE LATCHING MEANS WITHIN SAID CHAMBER EFFECTIVE TO LOCK SAID RAM AGAINST MOVEMENT, (H) SAID LATCHING MEANS INCLUDING A PAIR OF OPPOSITELY DISPOSED ROD MEMBERS ARRANGED TO BE RECEIVED IN