US2280404A - Motion checking or snubbing device - Google Patents

Description

Patented Apr.` `21, 1942 l Morlon CHCKNG on sNUBrNG DEvIcE `Lester,(lFrey, Cincirmati,` Ohio, as signor to The i f "American Laundry Machinery Company, Norv Wood,f0hio, a corporation of Ohio i sppicaeon'sugsfv, 1939, serial Ndesassa Y (ci. 38.-25)

e e Y noname.

This' invention relates `to garment pressing machines and vmore particularly to la" motion checking or snubbing device,` `for `the movable head `member audits connected parts. h e' The object of the invention` is to provide` improved snubbing means which forms part `o f or Vis associated with the head-closing fluid,` motor,

doing away Withsupplemental or extra snubblng devices or attachments for the purpose and utilizing themotor not only as an actuator `for the` headitself, butfalso to control its motionyinja` `manner to avoid shock and jan I `A further object of theinvention is tolprovide r' a i snubbing arrangement of Vthe character 1described inl which the operating piston oi` ,fthe head,

ing stroke and effective over a reduced area dur` ing the latter part of itsl strokegto lreducevthe i headclosing force and thereby amplify theV snub-Y bingror cushioning'resistance applied as an" opposing force. y i l l v f `A furtherobject of the invention isluto; utilize 3 the-head closing fluid pressure motor, `by the ap`` plication of controlling devices thereto, for cushioning or snubbing the motiono'f "thehead lever and its attached partsasthey approach either end of the` stroke, that is to say, in leither the head closing orhead openingdirections..

Further objects of theinvention are in partiob` vious` and in part Will appear morein `detail hereinafter.` e y l -zy- In the drawing,` Which represents one `suitable embodiment of the invention, yFignl isa side elevation of a pressing machine,'with the headopen,

the control devices being illustrated'diagram'-` matically` and in section; Fig`- 2 is ardetail plan il view, on a larger scale, looking at `thefparts in l closingmotoris madeeiective throughout its'en- `tirelarea for the major `portionof theheadclosconnected tothe lever 3. i o l ed June s, leemte John- Pjsingiser, to" whehreferencel may be had for a more complete description of the parts, if desirable vorl necessary.

As illustrated, the garment pressing machine comprisesa suitable frame` ,IA onvvhich is supported a verticallymovable Workls'upportor bedrZjactuatedby a lever 3rop`erated` bya nal Apressure iiuid pressure motor 4, the piston rod of which is Intheupperportion of the is mounted the usual pivoted lever 5 carryingan upperfpress- `ing memberr or head 6, the ,rear armof lever 5` being connected tothe upper-one off'a pair of toggle links J, 8tl1e lower one of vvhicliI ispivoted at 9 to the Vstationary irameL: lll] indicates `the usual head openin'gtension,springs and Il the head closing motor, Whichfiisof the, huid `pressure variety` Withfits piston" IZ Working in a "Yalve lsison M lever `22. Still another object is to provide anarrange- .ment of this kindwhich is readilytadjustable to Vvary the cushioning or snubbing effect; v, i f

cylinder |3` and, having .a rod Mextendin-g out through `one end of` the cylinder andpivotally connected at i5 to the lower',togglelinkf8-`` i l The control devices include Atvvo valve mechanisms, respectively marked hl,y I1`, valve mechanism |36 including a `normally `closed inlet .valve i8, and valve mechanism Ivl'inclu'ding a normally closedv inlet valve Igan'd a normally open outlet valve 2|).` n e L e e a rod 2| actuatable by the finger Thel casing oi valvemechanism His provided withanexhaust port "23 andv its valves `lil and 20 are on astem 24 actuatable bythenger lever25.

"26 illustrates the conduitcommunicating with a sourceof uid Ipressureto supply motive fluid. r By depressing bothof the finger `levers 22, 25,

one by each hand, iiuid pressure is permitted to flow fromfthe supply pipe 26, serially through the A'twovalve mechanisms it, I'l` to the chamber the direction ofthe arrows `2--2 inFig.A 1, parts l being shown in section to illustrateinterior construction; and Fig. 3 is an elevation, from `the bottom in Fig. 2, parts beingshown in section on 1-l The `drawing `illustrates a conventional Lform `The garment press illustrated is of the sameY general form shown,` described andclaimed in a yprior patent,` No. 2,082,913, for Operating ,and

control mechanism for pressing machines, grantof garment pressing machine and control, which l of i themselves `form no part ofthe invention ex#` cept as they are included in the combination and h defined in the claims appended hereto.

-within motor H onpthe pressure face of the `piston I2, moving the same over and swinging the toggle mechanism and head lever from fullyopen toward closed position,` until finally the knuckle ofthe toggle levers moves slightly `beyond rfully `straightened position, with the lower toggle member 8 against the yielding kick back device 21,

In this position `of the parts the head is closed upon the bed,l but Without heavy pressure,

- ready for the application of iinal heavy pressure. l e Final heavy pressure is produced by -the final l pressuremotor `4, the flow of` pressure to `which iscontrolled` by Valve mechanism 28, including normallyclosed inlet valve 29 andernormally open exhaust valve 30 both attachedto a stem 3l actuatable by an arm 32 of a iingerlever 33.,` 34

\ vindicates an exhaust port. v

Vthe rback face of the piston.`

When the head hasbeen fully closed by operation of motor II, the finger lever 33 is elevated in Fig. 1, moving over the valve mechanism 29, and establishing communication from the supply pipe 26 to motor 4, the piston of which moves over and elevates the bed 2 against the now stationary head 3 and applying final heavy pressure. Of course, as soon as the bed begins to rise and apply pressure to the head, the ngers can be removed from the levers 22, 25. Ultimately the final pressure upon-the work is maintained by a latch lever .35 held by a spring 35 in locking engagement with the Alever arm 32, after the same is moved over, as described inthe Singiser patent referred to.v The press is released by forcibly depressing lever 33, which cams the lever 35 out of the way and permits the valve mechanism 28 to move to uid pressure release position, evacuating motor 4, and permitting `bed 2 to descend until, nally, the kick back device 21 throws the toggles 1'8 back over dead center and the press opens under'the influence of the tension springslll.

'I'he motion checking and snubbingv device forming the subject matter of the pres-ent invention, insofar as itaffects the closing stroke of the moving parts, includes a conduit 40 communicating at one end, at 4I, with thefar end of the cylinder I3 on the back face of its piston I2, in what may be called the inactive chamber of the cylinder, said conduit at its opposite end also communicating with the cylinder chamber at 42,'at a point short of the end of the stroke of the motor piston. In other words, as the piston I2 moves along cylinder I3, and at just about the. time when the head is, for example, two inches from'the bed, said Vpiston I2 passes by and exposes the port or opening 42.

Theinactive chamber of the cylinder also com- `municates by a pipe'43 with an adjustable relief or vent valve 44 and a check valve 45 seating outwardly.

During the first portion of its stroke, until the piston I2 reaches the port 42, the fluid pressure supplied tothe active chamber of the motor Il is effective over the entire piston area and` exerts the maximum possible head closing effect. The relief valve 44 is the only outlet for compressed uidrfrom the inactive chamber on the back face of the piston, and said Valve 44 is adjusted to such area, by manipulation of its handle 46, that it will not materially hinder or retard advance of the piston during the first portion of its closing stroke, `so that head closing movement proceeds in the normal way with- ,J

out retarding effect. However, as soon as the port 42 is uncovered, a supplyoffluid pressure enters the pipe 40 at 42 and flows through said p ipeand into the inactive cylinder chamber on OfV course, this fluid pressure has escape through the relief port 4 4, but the area of said port is such as to choke free -flow of the full fluid pressure eiTect. As the resultwhen the port 42 is passed, practically the full pressure of the fluid pressure supply'is built up on the back face of the piston. Consequently, during the last, two inches or so of head travel, piston motion is produced by fluid pressure, the net value of which is, due to the area of the piston rod, the differential in the areas on the two faces of the piston. Opposed to piston travel is the restriction now effective as a retarding force at the valve 44. The result is that the final travel of the head closing piston is checked and the head motion is effectively snubbed and jar and shock are avoided and prevented.

Of course, so long as the two manuals 22, 25 are depressed, fluid pressure will escape through the valve 44, but in this type of control mechanism the manuals 22, 25 are released as soon as the final pressure motor 4 becomes active, so that further ow to the cylinder I3 is cut off and the fluid pressure therein is evacuated. Upon return of the piston I2 to its original position, when the head opens at a later stage of the cycle, air freely enters the inactive chamber on the back face of the piston through the inwardly opening check valve 45, as will be obvious.

Means is also provided for checking the motion of the parts during head opening movement. As illustrated, the pipe 41 coming from valve mechanism I1 to motor II communicates with the active chamber of said motor by way ofV a check valve 48 seating outwardly, so that full fluid pressure is quickly admitted to the cylinder past said valve. However, the pipe 41 also communicates with the active chamber and cylinder by Way of a conduit 49 and an adjustable needle valve 5i) (see Fig. 2)

When the manual 33 is forcibly depressed, to release the press by evacuation of final pressure motor 4, the head and its connected mechanism are moved to press open position rst by the starting effect of the kick back device 21 and then by the effect of the tension springs I0, which cause the piston I2 to return to its original position, moving to the right in Fig. 2. Relief or evacuation of fluid pressure from the active chamber in the cylinder can only occur by way of the needle valve 56; and pipes 49 and 41, because the check valve 48 seats outwardly and is closed. Consequently by proper adjustment of the valve a retarding effect may be produced upon press opening movement, slowing lit down as much as may be desirable to avoid ard simple valves and pipe sections connected directly to the press closing motor, and producing a snubbing effect by control of that motor instead of by the attachment of devices auxiliary or additional to the motor itself. Of course, it will be realized that these motion checking devices are practical and operative only because the motor I I is merely used for press closing and not for pressure maintaining purposes, pressure being evacuated therefrom at the time when the press is maintained closed by thepressure in motor 4.

What I claim is: v

l. A pressing machine comprising relatively movable head'and bed pressing members, a cylinder and piston motor operatively connected to one of said members for closing the press, means f operatively connected with the other of said members for producing pressure between said members, the cylinder chamber of said motor having active and inactive spaces on opposite sides of said piston, a pressure fluid suply to the active space of said chamber, and a passageway establishing communication between the active and inactive spaces of said chamber when the piston nears the end of its press-closing stroke.

2. A pressing machine comprising relatively movable head and bed pressing members, a cylinderand piston motor operatively connected toy one of said members for closing the press, means operatively connected with the other of said members `for producing pressure between said members, the cylinder chamber of said motor having active and inactive spaces on opposite sides i of said piston,la pressure vfluidsupply `to the active space ofsaid chambena passageway establishing communication between the active and inactive spacesof said chamberwhen the piston `nears the end .of its press-closing stroke, and

means providing restricted venting for the inactive space of said chamber.

3.\A pressingjmachine compr1sing relativelyr movable head and bed pressing members, a cylinder and piston motor operatively connected to `one of said members for closing the press, means j i operatively connected with `the other of said members for producing pressure between .said members, the cylinder chamber of` said motor having active and inactive spaces on opposite sides of said piston, a pressure fluid supply to the active space of said chamber, a passageway establishing `communication between the active and inactive spaces of said vchamber when the piston nears the endof its press-closing stroke, the inf active space of said chamber beinguprovided with rcommuni-cation to atmosphere by way of a 'restricted opening and also by Way of a check valve opening inwardly only.` o

4. A pressing machine comprising a pair of coacting relatively movable pressing members, a

cylinder and piston motor having a piston rod` `operatively connected with one of said members for moving the latter to safe-closed position adjacent ,the other member, means for thereafter holding the pressingmembers in pressure engagement, means-for supplying pressure fluid to the i active face of said piston to causea press-closing stroke thereof, said active face being of greater area than` the inactive `face on the piston rod side of said piston, said cylinder providing la chamber on the piston rod side of said piston preventingrapid loss of pressure `fluid from said chamber,` there being a port in'said cylinder uncovered by said piston near the end of its presspress-closing movement of said piston,` said cyll viding communication between said port and said closing stroke, and an open passageway ,pro-

viding communication betweensaid port and piston rod end of said chamber.

5; In a pressing machine of the type described" having aframe, head and bed pressing members movable therein, a head closing motor having a closed cylinder and having a piston "rod for closo ing said headand for placing a strut to hold said i head in said frame against retrograde movement, having a motor for pressing said bed againstsaid head when so held, means for supplying pressure iiuid to said motors in the order the Y i its press-closing stroke for supplying pressurey i fluid to the other face of said piston, and means vent at the other end of said` cylinder, and a check valve in the pressure fluidfsupply for said iirst named motor, said last named check valve permitting iiow toward said cylinder only.

8. Apressing machine comprising a pair of ccacting relatively movable pressing members, va

cylinder and piston motor for causing relative closing movement of said members,the cylinder chamber of said motor having relatively active and inactive spaces on opposite sides of said piston, means for supplying pressure fluid tothe active space of said `cylinder chamber for causing press-closing movement of said piston, said cylinder chamber providing a substantially fluidi tight inactive space, there being a` port in said cylinder uncovered by said piston near the end of its press-closing stroke, an open passageway providing communication between said-port and said inactive space, and means for slowly releasing pressure fluid from said inactive space, whereby pressure fluid admitted to said inactive space through said port retards the latter portion of the press-closing stroke of said piston.

9. A pressing machine comprising a pair of co acting relatively movable pressing members, aI cylinder and piston motor for causing relative., closing movement of saidy members, the cylinder chamber of said motor having relatively active and inactive spaces on oposite sides of said pis-' ton, means for supplying pressure fluid to the active space of said cylinder chamber vfor causing inder chamber `providing a substantially fluidtight ina-ctive space, there being a port in said cyli inder uncovered by said piston near the end of y its press-closing stroke, an open passageway proinactive space, and the face of said piston toward said active space being ofgreater area than the face of said piston toward said inactive space, whereby pressure fluid admitted to said inactive space through said port retardsthe latter portion of the press-closing stroke ofsaid piston.`

10. Al pressing machine comprising relatively movable head and bed pressing members, a cyl-U `inder and piston motor for-causing relative clos-H ing movement of said members, means for supplying pressure fluid to one face of the piston of said motor for closing the press, means rendered operative `by piston movement` near the end of Y for reducing the pressure of said uid against of their namingand meansl for evacuatingsaid first named motor after energizing, said second y `named motor; snubbing means for said first named motor including aport in the wall of said cylinder` uncovered by said piston near the end of its press-closing stroke,` and a conduit providing communication between said port and th piston rod end of `said cylinder. i

6. The combination `of claim 5 including la restricted vent in the, inder.

` '7.` The combination of claim 5 including a re- Vstricted vent in the piston rod end 'of said cylpiston rod end of said cylinder, a check valve communicating between the piston rod end of said cylinder and atmosphere,

said valve opening inwardly only, 4a restricted said other face toless than the pressurecf thev uid supplied to the first named face of the pis" l ton, whereby said piston will advance slowly during the latter part of its stroke in press Aclosing Y direction. l v

1l. A pressing machine comprising relatively movable head and bed pressing members, a cyl- I inder and piston motor for causing relative closing movement `of said members, means for sup'- plying pressure liuid to one face of the piston ofV said motor for closing the press, means rendered' operative by piston movement near the end of its press-closingstroke forv supplying pressure fluid to the other face of said` piston, and` said other face of said piston having less effective area ex` l posed to pressure fluid than said first named face, whereby said piston will advance slowly during the latter part of its stroke in press closing direction'. f

LESTER C. FREY

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