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Publication numberUS1874482 A
Publication typeGrant
Publication dateAug 30, 1932
Filing dateDec 3, 1928
Priority dateDec 3, 1928
Publication numberUS 1874482 A, US 1874482A, US-A-1874482, US1874482 A, US1874482A
InventorsForman Paris R
Original AssigneeNat Pneumatic Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Fluid pressure operated dcorlock
US 1874482 A
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Description  (OCR text may contain errors)

Aug. 30, 1932. P. R. FORMAN FLUID PRESSURE QPER'ATED DoonLocx 5 Sheets-Sheet 2 Filed Dec. i5, 1928 Aug. 30, 1932. P. R'. FORMAN FLUID PRESSURE OPERATED DOORLQCK Filed Dec. 5, 1928 5 Sheets-Sheet 3 PAR/s A. mRNA/v NVENTOR :iis ATTORNEYS.


This invention relates to a novel fluid pressure operated door lock actuated by fluid pressure from the source supplying door operating engine.

An object of this invention is the provision of a novel door lock adapted to be released l whenithe Vdoor is actuated by its actuating Yline 7 7 in Figs. 3 and 6;

engine to move said door into open position.

Another object of this invention is the provision of a novel door lock adapted to come into locking condition during the closing of a door by its engine and to stay in locked condition While said door remains closed during transit. f

Another cbj ect of the invention is the` provision of a novel door lock operated by fluid pressure from a door actuating engine, which door lock is adapted to open from and return to a locked condition.

yStill another object of this invention is the provision of a novel door lock adapted to be disengaged, leaving a railway `train door free to be opened by hand, when the fluid pressure for operating a door opening engine to open such door has fallen away to a point where it is insuilicient to actuate the door operating engine to open the door.

This invention resides substantially in the construction, combination, arrangement and relative location of parts all as will be more fully indicated hereinafter.

Referring to the drawings: f

Figure l is a partiallyl brokenv away plan view of the usual type of door actuating Huid pressure engine to be used in connection With my new device. Y n

Fig. 2 is a sectional view of the interior construction of my pneumatically operated door lock with various portions thereof removed for the sake` of Yclearness;

Fig. 3 is a plan view of my novel device;

Fig. 4t is a side view thereof; Y

Fig. 5 is an end view* thereofshowing the door lock in position to co-act with a door;

Fig. 6 is va sectional viewtaken along the line 6 6 in Figs. 4 and 5; i f Y F ig. 7 is a sectional view taken along the Fig. 8 is a bottom plan view of the :do or engine valve member; and.

Fig; 9-is a top plan view of the door engine valve seat member.

A Similar reference characters refer to similar partsthroughout the several views of thel drawings.

In Figure l We have the ordinary type of fluid actuated door engine where 1 is the casing thereof having two feed and cushion exhaust passages 2 and 3, either one of said passages adapted on the movement of the piston plunger unit 4 in one direction t0 operateas a feed passage, and when the piston plunger unit moves in the opposite direction, adapted to act as a cushion exhaust passage. As shown Figure l has "the piston pluno'er unit over at the right-hand end of its strolrei This will be adopted throughout the vdisclosure hereafter as signifying' that the mechanism actuated by said moving piston has placed the door, which it actuates, in

.a closed position, namely, when the piston is at the right-hand end of its stroke I considervthe door to have been closed, while .when the piston isat the left-hand end of the stroke l assume a door opened condition.

xMore centrally located in the engine casing are the two passages 4 and 5 adapted for free exhaust of the engine contained fluids von vthe'various strokes of the piston plunger unit.

6 represents the fluid chest analogous to the steam chest of an ordinary type of steam engine. Within this chest there have been diagrammatically shown the various port openingsg 7y representing the Vopening `from the feed pipe into the fluid pressure chest; l8

representing the port opening of the passageQ; 9 representing the port opening of the passage 4; 10 representingY the port opening to exhaust; ll representing the port opening of the passage 5 and l2 representing the port opening of the 'passage 3. Also within the Siiuidlpressure chest is shown diagrammaticallyy a connecting movable passage 13 and a more complicated connecting movable passagerll. l

Although it constitutes no portion of my invention I will now briefly describe the operation of this type of fluid pressure door engine. `The pressure coming in, let us say, at

7, feeds through the connecting passage 13 into the port opening 8 down the passage 2, and acting upon the face the piston 1unger unit 4', which we will presume to e at the left-hand end of its stroke, moves said unit over until eventually the passage is completely uncovered. At the same time Huid which was contained to the right of the iston plunger unit was freely exhausted during this movement by the unit operatingy thereon with its face 16'to freely exhaust such' fluid through the passage 5, port 11, connect- Yas ing unit 14, yport 10 and thence vto'the'atmos'- phere. As t e its motionpast the opening of passage 5 into the cylinder it operates to close said passage and the Huid still remaining to the right of Athepiston face 16 acts as a cushion exhaust, thatis, it is exhausted more slowly down the passage 3, port 12, connecting unit 14, port 1 0 and thence to the atmosphere.y

Thus the piston plun er unit 4 is moved f from the left-hand en of the cylinder to the right-hand end of the cylinder and as rit reaches the extreme end of its stroke is adually slowed up by a cushion action. Fry moving the connecting units 13 and 14 so that 13 covers ports 7 and 12 instead of v7 and 8, while the connecting unit 14 covers ports 8, 9 and'10 instead of 10, 11 and 12, the reverse operation will take place, namely, the door will be opened by the motion of the piston lplunger unit to the. left and said vpassa e 3, which before operated as a cushion exiaust passage, will now operate as afeed passage; while' passage 2, which beyfore'V operated as a feed passage, will ynow opy seat used with my door engine constitutes no part of my invention I will now, however, briefly describe the same. Referring to Fig. 8 for this purpose it will be seen that I have shown a bottom plan view of a valve member 43 adapted to on they flat valve seat member 44 shown in top plan in Fig. 9 with che parts 7, 8, 9, 10,11 and` i2 Opening thereinto. This valve member, in essence a cylinf drical disc ,43, or the like, is provided with lthe cuts 13 and 14 therein.'l Oscillation of the disc member 43, will, it is apparent, afford connection by cut 13 between ports 7 and 8 or.7 and` 12, and-by cut 14 between 10, 11

and-,12, or 8 9 and/10. Cut 14'is provided, as will be observed,with two ends a and b, only one of which is in operative position at one time, in other words either end a of cut 14 piston plunger unit continues extreme end of its stroke to the right. tained between the piston 24 and tlie washers vf26 is both an air body and the spring 27, the

connects port 8 with ports 9 and 10 or end Z) of cut 14 connects port 12 with ports 10 and 11, as will be observed in Fig. 1.

I have thus covered in detail the operating features of the door operating engine in order that I may show how it, as a unit, will co-act with my novel invention and do not intend in any way to rely upon theparticular type of engine shown as constituting a feature of my invention, but show it as one illustrative ltype of Aapparatus in connection with which my novel door lock may be used. Referring' again lto the fluid chest 6 it will be noted that lconnected to the port 8, which y may properly be calledtlie door-closing port,

since it is through this port that fluid pressure is admitted to move the piston plunger unit to the ri ht to close the door, is connected the pipe 1 broken away at 18-,19 leadin lto my novel locking mechanism shown in ig. 2.

Fig. 2 is a sectional view of the interior construction of my door lock somewhat envlarged with respect to Fig. 1 and wherein 19 represents the broken away connection of the pipe 17. The body of mynovel mecha- -nism shown in Fig. 2 at 20 has threaded therein the plug member k21y which has disposed centrally therein the tapered pipe tap 22 wherein the ipe 17 isthreaded. The other face of the p ug member 21 is counter-bored at 23. The interior of the cylindrical body 20 operates as the fluid pressure cylinder ofV my novel locking mechanism and contained therein is a standard piston 24 which has screwed therein the pusher rod 25 which yextends through the outer head of the cylinder body 20. 'Dis posed against the inner face of said outer ead are the washers 2G against which the piston 24 will seat at the Concombined action of both of which will be noted to be the tendency to normally returnl the piston 24 to the left-hand end of its stroke. The spring used is intended, of course, to be of such strength that, when the fluid' pressure acting on piston 24 falls below that value necessary to actuate the door engine, 1t (the spring) will in conjunctionwith the compressed air body mentioned return thepiston24 to the left end of its stroke. On the left-hand face of the piston 24 will be noted two bumps which, in sectional view, indicate a `projecting ring 28 cast purposely in the iston body 24 to provide against wear- `ing o thel face of the piston when it seats against the plug member 2l.

f It is thus apparent from the structure recited that when pressure is admitted to the pipe 17 the operation of this. structure is to move the piston to the right against the washers 26 under the iuid pressure thus admitted and against the resisting force of the izo spring and air body contained between the piston and the washers 26. In so moving the piston carries with it the pusher rod 25 which it will be shown hereafter operates to pull they lock into a locking position. Thus while fluid is fed continually down the pipe 17 from the door closing port 8 and the pressure is thereby maintained the piston of the locking mechanism will invariably be 'forced to the right and actuate the elements hereinafter described to lock the door, while if the feed pressure supplied to the engine should fall away to a point where it is insuflicient to actuate the piston plunger unit in the door engine to move the same to the left in order to open the door the effect will |be that the pressure having similarly fallen E in the pipe 17 the spring and contained air, between the washer 26 and the piston 24 return the piston 24 to its normal position, exhausting any air contained between the left-hand face of the piston 24 and the inner face of the plug member 21 through pipe 17 back into the source of pressure. Obviously this returns the pusher rod 25 and, as will be shown later, this operates to remove the locked condition of my mechanism. Thus when the pressure supply to my door engine falls away so that it cannot be operated to open the door, due to an accidental breaking of the feed pressure line, or by the intentional opening of such line to free eX- haust by an emergency valve, located in the car, my lock also will be opened, because the lock cylinder is then also exhausted, so that the door may be opened by hand, working, of course, against the piston plunger unit 4. On the other hand, it will be noted that while the pressure comes in through the door closing port 8 and operates on the piston plunger unit 4 to keep the door closed my locking mechanism also will be locked and thus while the pressure is maintained in a door locking condition my mechanism also is locked. There is one operating characteristic which yet remains to be described and that is the condition which obtains when fluid pressure is being admitted to open the door; and it will be noted that the port 8 is then connected by the connecting element 14 in the fluid pressure chest 6 to the exhaust port 10 and the Huid within the cylinder body will be exhausted through the pipe 17 and connecting element 14 to the atmosphere via port 10 along with the fluid closing pressure, so to speak, on the n left-hand side of the piston plunger unit 4. Thus briefly summing up the operation .of my mechanism it is something like this:

T' When the door engine is operated to close the door my mechanism provides an additional lock for the door. Vhen the door engine is operated to open the door my mechanism comes into an unlocked state and allows opening of the door. `fVhen fluid pressure fails and the engine may not operate at all then my mechanism comes into an unlocked state.

Referring to Figs. 3, 4 and 5 in which the cylinder body 20 is shown in plan and elevational views it will be seen that the pusher rod has extending therethrough a pin 28 which feeds through a hole 29 in the flattened end of said pusher rod shown in Fig. 2. This pin 28 works in the bifurcated arm 29 which is connected to the lifting arm 30,said lifting arm being pivoted for rotation to the framework 31 at 32 by the cotter pin 33, which frame-work also supports the body 20. The lifting arm has hollowed in its hammer end 34 a spring 37 attached to the outer face 35 of said hammer end by the washer and cotter arrangement 36. This spring extends through the hollowed out hammer end pastthe inner face of said hammer end and through a hollowed out portion of the lock bar 38 and is attached to said lock bar by a smaller washer and cotter arrangement 39. The lock bar 38 is provided with an enlarged portion 40 adapted to be rotated about a pin 41 located in the bi- .furcated arm 42 carried by the frame-work 31. Thus it will be seen that when the arm 30 lifts the hammer end 34 tends to move away from the lock bar 38 and also tends to tension the spring 37. The lock bar 38 and the hammer-ended member 34 being interconnected as they are by spring 37, which although resilient acts, nevertheless, as a rigid link, the lock bar and hammer-ended member move down together until the locking end 43 of the lock bar seats in the seat 44 on the door. While a locked conditionexists the spring 37 is continued under tension. On the opening movement the spring 37 is compressed by the member 34 until it acting together with the member 34 are suflicient to lift the latch and open the same` against the latchs weight and the friction that is present between elements 43 and 44, at which time the latch or lock bar will be lifted, the members 30, 34, 37 and 38 all acting and moving as'if rigidly connected to each other. It is thus apparent that the mechanism which I have disclosed will operate as a positive acting lock for a railway train door to keep said door closed while said train is running and while said door would be normally closed due to the door closing engine and, on the other hand, when said door is opened said lock will operate to allow said opening with and under the operation of the door engine and, still further, when said engine is incapable of functioning said lock will Y operate to permit of the door being opened by hand. Y

Inasmuch as many changes could be made in the above constructions and many appa-rently Widely different embodiments of the invention could be Vmade without departing from the scope thereof it is intended that all matter contained in the above description or L.:

shown in the/accompanying drawings shall be interpreted as illustrative and not in a limiting sense. f

It is also to be understood that the language contained in the following claims is intended to cover all the generic and specific features of the invention herein described, and all statements of the scope of the invention, which, as

said lockbar tov move the lock bar in the other direction, one of said movements being effected by the fluid pressure of lthe piston and the other by the removal of said pressure.

In testimony whereof I have hereunto set my hand on this 28th day of November, A. D.r1928.


a matter of language or philologically speaki ing, might be said toffall therebetween.

What Iv seek to secure by United States Letters Patent is: f

'1. In a fiuid pressure actuated door lock mechanism having a cylinder, a piston disl'posed within said cylinder and movable therein, an inlet port and means normally tending to hold said piston against said inlet seating in said seat, a hollowed out hammerf j ended rotatable arm having a bifurcated eX- tension, a spring attached at one end to said latch member and secured at its other end kto the rotatable arm at its hollowed out portion,

and means for actuating rsaid rotatable arm byits bifurcated extension including a iuid pressure o erated piston member.

3. In a uid pressure actuated lock mechasaid cylinder, the combination of a latch member, a latch operating member connected to the piston for operation thereby and a resilient member connecting' said operating member to said latch member.

4. In the type-of mechanism described, having a single acting piston disposed in a casing, a piston rod, and means to normally n hold said piston against movement, the combination of al lock bar, an oscillatable member having a bifurcated end engaging with said piston rod and a hollow hammer end, and a'resilient member for operativelyl connecting said oscillatable member at said hollow hammer end to said lock bar.

ynism having a cylinder, a piston disposedin .5.'In the type of mechanism described,

'having a cylinder with a pressure actuated piston therein, said piston being provided with a piston rod, means to normally hold said piston against movement, a lock bar, a rotatable member having a bifurcated end y engaging with said piston-rod, and a hollow hammer endv engaging with said lock bar to move it in one direction, and a resilient mem- 55' ber connecting said hollow hammer end of

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3090644 *Oct 18, 1961May 21, 1963Daimler Benz AgDoor lock
US5150796 *Jul 18, 1991Sep 29, 1992Rotex, Inc.Retractable, air pressure actuated hold-down clamp
US5186333 *Sep 27, 1991Feb 16, 1993Rotex, Inc.Top cover clamp for screening machine
US6073979 *Oct 28, 1997Jun 13, 2000Rotex, Inc.Adjustable clamp and force level indicator for screening machine cover
U.S. Classification292/201, 292/96, 49/280
International ClassificationE05F15/02, E05F15/00
Cooperative ClassificationE05F15/02
European ClassificationE05F15/02