US2212196A - Pressing device - Google Patents

Description

Aug. 20 1940. H. A. PERKINS PRESSVING DEVICE Fi1ed,Ju1y 6, 1936 4 Sheets-Shoot 2 Aug. 20, 1940. H. A. PERKINS PRESSING DEVICE Filed July 6, 1936 4 Sheets-Sheet 3 l/w ew 7-0;? fifi/a A}? PAPER/(1N5 ATTORNEY Aug. 20, 1940. PERKlNs I 2,212,196

PRESSING DEVICE Filed July e, 1956 4 Sheets-Sheet 4 /NI EN TOR 422 JGZRULD A PERKINS ATTORNEY Patented Aug. 20, 1940 UNITED STATES PATENT. OFFICE PRESSING DEVICE Application July 6, 1936, Serial No. 89,044

7 Claims.

My invention relates to pressing machines and particularly but not exclusively to devices of this character adapted to press wearing apparel.

One of the objects of my invention is to provide a pressing device which will be extremely simple in its construction and operation and in which the pressure may be varied to any extent up to the structural strength of the machine itself.

Another object is to provide a pressing device in which it will be impossible for the hands or any other portion of the body of the operator to be subjected to a pressure suflicient to cause pain or injury. More specifically, this last object in cludes the provision of coacting means whereby the development of an appreciable pressure between the pressing elements is positively prevented until they are moved substantially into contact or in such close proximity to each other that it is impossible for the fingers or hands of the operator to be between them.

In the fundamental embodiment of my invention, an object resides in the provision of a hydraulically operated press in which the pressing elements are entirely independent of the pressure developing mechanism except when said elements are substantially in contact, and in which the usual safety measure of providing control means requiring both of the operators hands in a manipulation of the press is unnecessary.

In one embodiment of my invention, it is contemplated that an initial operation of the pressing device be performed by hand; however, in the preferred embodiment, it is proposed that an entire cycle of operation thereof be performed by invention resides in the provision of means for moving the presser head into close proximity to the buck and thereafter effecting a compression of the two pressing elements in response to an operation of power operated means. A further object resides in the provision of spaced means operable by hand for controlling the application of a comparatively high pressure to the presser head thereby forming a safety appliance for the 45 benefit of the operator; and another object is to provide a further safety device whereby an operator is prevented from applying full pressure upon the presser head when the device is initially operated. A still further object resides in the novel arrangement and correlation of the various elements and control means of my press ing device in such a manner that the presser head will be initially actuated to a point predeterminately spaced from the buck under a comparatively small moving force whereby it is impossible supplied power. Hence, a further object of my for an operator accidentally to receive serious injury.

With these objects in view my invention includes the novel elements and combinations and arrangements thereof described below and illustrated in the accompanying drawings in which- Fig. 1 is a side elevation of my device partially in section to show details of the construction and operation thereof;

Fig. 2 is a fragmentary vertical elevation, partially in section, showing the modification of a detail;

Fig. 3 is a fragmentary perspective view of the means for developing pressure and the controls for the machine;

Fig. 4 is an elevation view of the hydraulic cylinder partially in section;

Fig. 5 is an elevation view showing the details of a control valve;

Fig. 6 is a side elevation of a preferred embodiment of my device, partially in section and illustrating the various power transmitting elements in one position;

Fig. {7 is a fragmentary perspective view of a portion of the fluid circulating system and the controhmeans associated therewith;

Fig. 8 is a diagrammatical representation of the fluid circulating system and devices included therein;

Fig. 9 is a view generally similar to Fig. 6 but showing the various power transmitting elements in another position;

Fig. 10 is a fragmentary front elevation view of the pressing device illustrating the hand operable controls;

Fig. 11 is a fragmentary side elevation view of Fig. 10; and

Fig. 12 is a fragmentary elevation view of the hydraulic piston with one of the regulating valves and an automatic control associated therewith.

Referring to Figs. 1 to 5, wherein I have illustrated one embodiment of my invention, my pressing machine comprises a cast frame I conforming in general to the frames now commonly employed and which is supported upon a base 2. 3 is the usual pressing bed or buck and 4 is the presser head which is carried by the arm 5 pivotally mounted on a shaft 6 secured in the frame I, the arm 5 having a rearwardly extending arm or lever I carrying a counterweight 8. .In my device this arm or lever I is provided with an opening 9 for a purpose which will be later described.

Referring first to Fig. 3, I0 is a motor which drives a liquid pump l l. The liquid to be pumped, preferably oil, is contained in the reservoir i2.

Centrally mounted on the base 2 of the frame is a cylinder l3 having its axis vertically disposed and having mounted therein a piston |4 adapted to be moved upwardly by hydraulic pressure developed by the pump The cylinder |3 is mounted on a base l5 having a passage l6 therein communicating through the opening l1 with the cylinder below the piston H. The pump draws oil from the reservoir l2 upwardly through the pipe l8 and forces it through the pipe l9 into the passage'l6 in the base of the cylinder l3. Communicating with the passage I6 is an outflow pipe which conveys the oil back to the reservoir I2 through the operator-actuated valve 2| and the pipe 22. When the valve 2| is opened, it forms together with the pipes 20 and 22 an oil by-pass for the cylinder, and when no pressure is being exerted between the presser head and the buck the oil is constantly and freely circulated from the reservoir upwardly through pipe l8, through pipe I9, passage I6, pipe 20, valve 2| and pipe 22 back to the reservoir l2. When the valve 2| is closed hydraulic pressure will be developed in the cylinder below the .piston l4 and will force it upwardly. For the purpose of regulating the pressure which will be developed I provide the valve 23 which communicates with the pipe is as shown in Fig. 1 and also with the reservoir through the vertical pipe 24. A pressure gauge 25 is also installed in pipe ill for the purpose of indicating the pressure in the liquid circulating system. By regulating the opening of the valve 23 by means of the hand wheel 26, the maximum pressure developed on the piston it may be controlled.

A piston rod 21 extends upwardly through the top head of cylinder l3 and carries the yoke 28 to which are pivotally connected the vertically depending links 29 and 30 at either side of the cylinder. These links, at the bottom, are pivotally connected to the lever 3| which is bifurcated as shown at 32 in Fig. 3 and pivotally mounted in the rear of the frame at 33 to form one element of a power-transmitting mechanism. The other element 34 of the power-transmitting mechanism extends in a substantially vertical direction and is pivotally connected to the lever 3| at 35 which point of connection is very close to the pivotal connection 33. The element 34 which leans a little to the left of the vertical as viewed in Fig. 1 forms. a push-rod, the upper end of which is adapted to coact with the bottom of the lever 1 when the parts are in the relative positions shown -in the dotted lines in Fig. 1, and thus transmits pressure from the hydraulic cylinder to the arm 5 thereby compressing the pressing elements 3 and 4. As the pressure in the cylinder I3 is relieved and the element 3| is returning from the position 3| to the position shown by the solid lines in Fig. 1, the upper end 55 of the rod 34 moves to the right (as viewed in Fig. 1) from the position 55' and enters the opening 9 in the lever 1 which is carried downwardly by the counterweight 8 to separate the pressing elements. The adjusting screw 51 is in this embodiment provided to insure this movement.

Thevalve 2| is actuated by the foot levers 36 and 31. These levers are pivotally mounted in the frame to move independently of each other as shown at 38.. The valve 2| is closed by pushing the stem 39 (see Figs. 3 and 5) upwardly, and is opened by pulling the stem 39 downwardly. In order to accomplish these movements by means of the foot pedals 36 and 31 the valve 2| is pro- ,iee

sided with a depending yoke in which an element ii is pivotaily mounted at 42. At the left, as viewed in 3 and 5, the element 4| is provlded with an arm 43 which is pivotally connected to the stem 39 at 44; the arm 43 being provided with a slotted opening as shown at 65. Element ll is also provided with slotted openings 36 and 51 in which are connected the operating levers for the valve 28. The rear end of the pedal lever 36 is connected with the element 4| at the left of the pivot 52 by means 01" a rod 48 and clevises 4S and 50 which are adjustable so that the effective length of the rod 36. may be varied. The rear end of the pedal lever 31 is also connected to the element (ii at the right of pivot 42 by means of the adjustable clevlses 5i and 52 and the rod as shown. From the foregoing, it will be apparent that when "pedal is depressed the stem 39 will be forced upwardly to close valve 2| and the rod 53 will be forced downwardly thus raising pedal 3? as pedal 35 is depressed. To open valve 2|, pedal 31 is depressed which pulls stem 39 downwardly to effect this end.

In operation, assuming the valve to be partially open, and the motor Ill to be running and oil to he circulating in the liquid circt. ting system, the garment to be pressed is patcd upon the buck, and the presser head ls then lowered manually by grasping the handle Ed. when the presser head 4 has been brought into contact with the buck or the garment thereon, the pedal 35 is depressed thus closing the lay-pass around the cylinder. Oil pressure will be developed in the cylinder l3 and the piston It will be forced up wardly. This will raise the bifurcated end of the lever 3| which will permit the rod 34 to tilt backwardly until the top 55 moves to the position 55' beneath a solid portion of the lever As the piston continues its upward movement, pressure will be applied to lever 1 through rod 3% and while there will be some slight upward movement of the push-rod 34, it will not move substantially from the position 34 shown. in Fig. 1 while the pressure is applied. The maximum pressure developed will be indicated by gauge 25 and will depend on the extent to which valve 23 is closed. The desired pressure in the system may be regulated by means of the hand wheel 26, and it is unnecessary thereafter to change the valve setting unless a different pressure is desired. After pressure has been applied for a sufiicient interval it is necessary only to depress lever 31 with the foot which will open the valve in the by-pass around the cylinder to relieve the pressure. As the lever 3| descends from the position 3| to the position 3|, the rod 3 3, due to the coaction of the adjusting screw 51 with the lever 3|, will tilt to the right until the upper end 55 reaches the opening 9 in lever 1, whereupon the counterweight will pull lever 1 downwardly and the pressing elements will separate. To repeat the operation it is only necessary to lower the head 4 into substantial contact with the buck, whereupon the upper end of the push-rod 55 will tilt back to the position 55', as pedal 36 is depressed, and the pressure to which the valve 23 has been adjusted will be developed between the buck and presser head. In order that the top 55 of rod 34 in tilting backwards may Just clear the solid part of lever 1 with which it coacts when in the position 55', the length of rod 34 may be varied by the adjusting means 56.

If desired, the element 34 of the power-transmitting mechanism may be pulled forward from the position 34' into registration with the opening 8 simultaneously with the opening of valve 2| by means of the following mechanism. The lever 31 may be provided with an integral arm 58 to form a bell crank on the pivotal connection 38. The push-rod 34 may be connected to the upper end of this crank arm 58 by means of the rod 59, as shown in Fig. 2, and, in order to allow some downwardmovement of pedal 3! before a substantial pull is exerted on the rod 59 a helical spring 68 may be provided intermediate the arm 34 and the nut 6| which connects rod 58 to the arm.

From the foregoing it will be apparent that in this embodiment of my device it is not necessary for the operator to have both hands occupied when pressure is applied between the buck and presser head in order to avoid the accidental crushing of the hands. This is so because the presser head must first be manually lowered substantially into contact with the buck before the push-rod 34 of the power-transmitting mechanism will move to the left into pressing position as shown in the dotted lines in Fig. 1. Since the presser head and the buck are substantially in contact before any hydraulic pressure can be applied it will be impossible for the operator to have any portion of his hands between the pressing elements when the pedal 35 is depressed.

In the preferred embodiment of my invention, I have designed a pressing device wherein the entire operation thereof is carried out by means of supplied power and which comprises associate-d elements preferably including a hydraulically operatedpiston, as willhereinafter appear, for moving the presser head into close proximity to the buck under a comparatively low pressure and thereafter effecting a compression of the two pressing elements under a comparatively high pressure. Referring to Figs. 6 through 12 which illustrate the preferred embodiment of my invention and particularly to Fig. 6. it will be noted that the frame of the press, the buck, presser head, hydraulic cylinder and associated power transmitting elements for actuating the presser head in response to the application of pressure to the piston of the cylinder, primarily, are substantially the same as the corresponding elements illustrated in Fig. 1. The lever 31 of the toggle which is connected to the links 29 and 30 associated with the piston of the cylinder l3, however, has connected thereto a link 5| at a point intermediate its length. Link 5| is pivotally connected to a cam 52 which in turn is pivotally mounted upon a shaft 53 secured in the frame. of the machine. A member 54 which preferably comprises two coextensive, spaced parallel bars is pivotally supported on a shaft 65, secured to the frame of the press, the member 64 having pivotally secured at one end thereof a yoke 56 and at a point intermediate said yoke and shaft 55 a rotatably mounted cam follower 51 which is adapted to transmit motion from said cam to the member 64. A rod 68 which passes through openings in the two arms of yoke is maintained in position relative thereto by means of the collar 59 which is secured to the rod and a spring 10 interposed between the collar 58 and one arm of the yoke 66. The upper end of rod 68 is threaded as indicated at H whereby the same may be received in a threaded opening in a shaft 12 and adjustably secured thereto. Shaft 12 is rotatably mounted in a member 13 and extends through an opening "I therein of a size sufficient to permit rod 58 to extend therethrough and rotate to a limited degree about shaft 12. The member 13 is pivotally supported on the shaft 6 which supports arm 5 and the end thereof is formed operatively to engage the rearwardly extending arm or lever I. An actuation of the piston of the cylinder iii to raise lever ll of the toggle will, through link 3|, rotate cam 82 which in turn will cause member 64 to pivot on shaft 85 and, through rod 68 and yoke 66, rotate member 13 and arm 5 about their pivotal axes.

The foregoing described combination of ele-' ments is utilized in moving the presser head 4 into close proximity with the buck 3 and accomplishes the same operation which in the first embodiment of my invention herein described was accomplished by hand.

For a very eiilcient and practical method of power operation of my press and one particularly adapted for power control whereby the magnitude of the pressure applied to the pressing elements is predeterminately varied throughout the cycle of operation of the press, I have designed a fluid circulating system together with controls therefor which will best be understood by reference to Figs. 7 and 8. A pump Il'draws fluid from the reservoir I2 and passes the same through the pipe l8 and into the base of the cylinder l3 as hereinbefore described with reference to Fig. 3. The base of the cylinder 18, in this embodiment, is also connected through a pipe 14, in which a valve 15 is disposed, and through two pipes 16 and 11, in which valves 18 and 19, respectively, are disposed, and through pipe back to the reservoir l2. The pipes 18 and 11 form parallel paths for the flow of fluid so that fluid will still pass from cylinder l3 bacli to the reservoir II in the event one or the other of valves 18 and 19 are closed. The casing of valve 19, as illustrated in Fig. 7, is provided with a depending yoke 8| which forms a pivotal support for lever 82 to which is connected the shaft 83 for actuating the valve rod of the valve 19. Lever 82 has secured thereto as by means of a clevis 84 a rod 85 which in turn is secured to .a foot-operated pedal 86 which is pivotally supported on a shaft 81 extending transversely of the press and supported in the frame thereof. The lever 82 has also connected thereto a spring ,88 which is connected to a lug 89, preferably secured to the base 2 of the frame, the spring 88 serving normally to maintain the valve 19 in open position.

The valve 18 which is disposed in the pipe 16 is provided with an operating lever 80 to which. is adjustably secured a shaft 8| which is provided with an angularly disposed end portion adapted to be received in a slot 92 in the member 54 (see Fig. 6).

Valve 18 normally is in closed position when the elements of the pressing device are in the position illustrated in Fig. 6 which, of course, is in the unactuated position of the presser head 4. Hence, when pedal 86 is depressed, thereby closing valve 19, valves 18 and 19 will be closed at the same time whereby the piston within the cyl nder I3 is subjected to the full fluid pressure which is developed by the pump II and limited by the valve 23 in the by-pass pipe 24. Under these circumstances, lever 3| of the power-transopposite side of its pivotal axis will move downwardly to actuate lever 90 of valve I8 in a valveopening direction. It will be seen, therefore, that upon an actuation of presser head 4 into pressing position, the fluid pressure exercised in carrying out this movement is limited and predeterminately controlled by the manner in which the valves I8 and I9 are associated in the return line of the fluid circulating system and the correlated operation of the valve I8 with movement of the presser-head.

The shaft Si is adjustably secured to the operating lever 90 of the valve I8 by means of the adjusting nuts 93 which are threaded on the end of the shaft and, serve to regulate the degree of movement imparted to the lever through an operation of the member 64. Hence, it is evident that by adjusting the relative movements of the member 64 and lever 90 the presser head 4 may be moved toward the buck 3 under a desired pressure. Furthermore, in connection with the foregoing described operation of my press, it will be noted from an inspection of Fig. 9 that the cam 62 and follower 61 may be so designed and arranged, although such a construction is not essential, that after a predetermined move- .ment of the presser head 4 through an actuation of said cam and follower to position the same in close proximity to the buck 3 the cam follower 8! bears against the cam 62 at the point 94 which point represents the high point or point of maximum radial displacement of the periphery of the cam from its pivotal point toward the fulcrum of member 64. In other words, the cam and follower may be designed to impart only a predetermined degree of movement to the presser head 4. Hence, in view of the configuration of the cam surface and because of the limited pressure under which the presser head is moved, being substantially sufficient only to overcome the weight of the presser head and lever arm, it is possible for an operator to raise the presser head against the pressure transmitted theretothrough the cam and associated mechanisms.

After the initial operation of my pressing device under supplied hydraulic power, as above described, it follows that the pressing elements are in position to be compressed under a comparatively' high pressure head. To accomplish this result, I have interposed in the pipe I4 the valve I as illustrated in Figs. '7 and 8. The downwardly extending operating shaft 95 of the valve member of valve 15 is connected to a lever 84 which in turn is secured to a shaft 91 suitably J'ournaled in bearings in the frame I of the press. Shaft 91 also has secured thereto a lever 98 provided with a slot 99 within which is adapted to be received 9. depending link portion I00 of a yoke IN. The yoke IOI preferably extends to an appreciable'and preferably equal distance on both sides of the portion I00 and has pivotally secured at the ends thereof connecting rods I02 which extend upwardly and are connected at their upper ends to one arm I03 of bell cranks I04 (see Figs. and 11). The bell cranks I04 are spaced an appreciable distance from each other and carry levers I05 which are disposed in a position to be actuated by the hands of the operator of the press. A spring I06 is preferably provided and interposed between the frame of the press and arms I01 of the bell cranks in order to provide a cushioning effect when the bell cranks are operated. The two levers I05, connecting rods I02 and yoke IOI are associated and designed to prevent the operator from rotating shaft 91 and thereby closing the valve II merely by depressing one of the levers I05. For example, if one of the levers I00 were depressed, yoke IOI would pivot about its point of connection with the connecting rod of the other lever and hence lever 98 and shaft 8'! would be rotated to a considerably less extent than if both levers I05 were depressed together in which event full upward movement of the connecting rods would be imparted to the yoke IOI. Obviously, valve is arranged so that the movement of its operating shaft sufficient to close the same is of the order of a movement impartable thereto by said yoke only when both levers I05 are depressed together. In other words, the foregoing described combination of elements forms a safety device provided to insure against accidental injury to the hands of the operator.

Obviously, when 'the valve 15 is closed, the valves I8 and I9 are rendered, ineflect, inoperative and the piston in the cylinder I3 will be subjected to the full, regulated pressure developed by the pump II. In this connection, it will be understood that the element 34 of the powerlever I. When this has bccurred, the operation of the press is effected in precisely the same manner as hereinbefore described.

In reference to a'detail, it will be noted that in the latter embodiment of my invention element 34 is provided with a bracket I08 and a shaft I09 is passed through an opening therein and secured to the lever 3| of the toggle. A compression spring H0 is interposed between the bracket and lever 3| and a compression spring I II is interposed between the other .side of the bracket and an adjusting nut 2. This arrangement forms a positive and resilient means for maintaining the element 34 in a cooperable position relative to the lever I and serves the same purpose as the combined adjusting screw and weighted construction'disclosed in Fig. 1. In other words, spring H0 serves precisely to position element 34 in a position, when the presser head and buck are closely spaced, to be moved initially upon an actuation of lever 3| into engagement with lever I; and, after a pressing operation has been performed and the pressure relieved, spring III serves to return element 34 to its normal position wherein it passes within the opening 9 and permits the presser head 4 to return to its unactuatedposition.

In order to relieve the pressure in the cylinder I 3 after a pressing operation has been effected, I have provided a pedal 3, pivotally mounted on the shaft 81 and provided with a vertically extending arm I I4 adapted to engage a lever II5 secured to the shaft 91. The arm H4 is preferably provlded with an adjusting screw H6 in order to permit relative adjustment between the arm I I4 and lever I I5. It will be noted that valve I0 is provided with the spring 88 for opening the valve when the pressure is relieved on the pedal 08; however, the valve 15 is adapted to remain in closed. position after an operation of the hand levers I05 and, of course, will remain closed until pedal H3 is depressed'and the shaft 91 is rotated in a direction to open the same.

By way of a further safety appliance, I have provided m. illustrated in rm.- 12, which a designed to prevent an operation of the press through a complete cyclein response to a depression of the two, hand-operated levers I88.

The base of the cylinder I8 is here illustrated as including a passage I II which is adapted to communicate with the cylinder and valve I8. It will be seen that the exteriorly extending pipe 14 is dispensed with in this design of my invention 7 and that a more compact assemblage is eifected. It will be noted in this connection that the operating shaft as of valve I extends vertically thereabove and has connected thereto, by suitable means including, for example, a pin and slot I. The end of lever l2l, as indicated at I25, is

designed to extend beneath the yoke 28 connected between the piston shaft 21 and the links 28 and 88 of the piston assembly. Inasmuch as shaft 85 of the valve extends through a suitable opening in the lever I, the collar H8 and compression spring 8 will permit only a limited movement of the shaft 85, depending upon the adjustment of the collar but insufilcient to vary the fluid pressure in the cylindenin response to an operation of the hand levers I05 and thereafter the pressure applied to said levers will be transmitted to the lever HI and, obviously, movement of this lever is prevented through its engagement with the yoke 28. However, the above elements are so designed and arranged that when yoke 28 has been raised to its maximum height under the joint control of the valves I8 and I8, it will. then permit sufllcient movement of shaft to close valve 15 to efl'ect a pressing operation. Hence, with this ar-'- rangement, the operator is prevented from effecting a pressing operation of my pressing device merely by depressing the hand-operated levers. The spring H9 may be dispensed with and the collar H8 secured to shaft 85 in close proximity to the lever l2l. However, the spring tends to reduce noise and eil'ect a smoother operation.

In view of the hereinbefore described operation of the various elements of my press in conjunction with the specific descriptions thereof, the cycle of operation of the press in its entirety should be clear from the following description of the method of operation thereof. Assuming that a garment or like object is arranged on the buck, the operator depresses pedal 88 and maintains the same depressed against the operation of spring 88 while the presser head 4 is moved under a comparatively low pressure head into close proximity to the buck 8. Thereafter, by depressing the hand levers I05, a compression of the two pressing elements is effected under a comparatively high, predetermined pressure head and, upon a depression of pedal ll3-the pressure is relieved and presser head 4 moves upwardly under the gravitational effect of the weight 8 to its original, unactuated position, the various ele ments being then positioned in readiness for a second operation.

' Although I have illustrated and described a particular fluid circulating system as a power means, it will be understood that equivalent arused scription rather than of limitation. Hence;

changes within the purview of the appended claims may be made without departing from the 'true scope and spirit of my invention in its broader aspects.

What I claim is: r a

1-. In a pressing device of thecharacterdescribed comprising a movable presser head and a buck, hydraulic-pressure actuated means including a cylinder and piston for moving said presser head toward said buck, manually operable means for eflecting an operation of said hydraulic means to move said presser head toward said buck, means for controlling the pressure in said cylinder, means for operatively connecting said presser head with said control means; said connecting means being so constructed and arranged that movement of said presser head toward said buck effects an operation of said' control means progressively to reduce the pressure in said cylinder whereby said presser head is moved into closely spaced relation to said buck under a comparatively low pressure, and means for effecting, when said presser head and .buck are so closely spaced, an operation of said hydraulic means to reservoir and cylinder for supplying fluid tosaid cylinder and returning it i'to said reservoir, said cylinder being provided with a piston operatively connected to said presser head, a flrst valve disposed in said system and manually operable to control the fluid pressure in said cylinder and a second valve disposed in said system including valve-operating means operatively connected with said presser head, said valves being so constructed and arranged in said system that said first valve may be manually actuated to effect an operation of the piston in said cylinder to move said presse'r head toward said buck under the fluid pressure developed in said system and said second valve being operableprogressively to decrease the pressure in said cylinder as said presser head approaches said buck.

3. In a pressing device of the character described comprising a movable presser head and a buck, a fluid circulating system including a fluid circulating pump and a cylinder provided with a 1 piston, means for transmitting motion from said piston to said presser head, said system including a fluid supply reservoir, means for supplying fluid progressively to decrease the pressure in said cylinder as said presser head approaches said buck.

4. In a pressing device of the character described comprising a movable presser head and a buck, a fluid circulating system including afluid reservoir, a fluid circulating pump and a cylinder provided with a piston operatively' connected with said presser head for developing pressure between said head and buck, a conduit for supplying liquid from said reservoir to said cylinder and returning it therefrom to said reservoir, means connected in said conduit and manually operable to effect an. operation of said piston to move said presser head toward said buck, means for progressively decreasing the liquid pressure exerted on said piston as it is actuated to move said presser head toward said buck, means for thereafter eflecting an operation of said piston to urge said presser head toward said buck under a comparatively high pressure, means forming a by-pass for liquid around said cylinder and an adjustable valve disposed in said by-pass for regulating the liquid pressure developed in said system. 7

5. In a pressing device of the character described comprising a movable presser head and a buck, the combination with fluid-operated means comprising a cylinder provided with a piston, of

, manually operable means for eilecting a fluid- "actuated operation of said piston, means for moved to a position closely spaced from said buck and held there under comparatively low pressure.

6. In a pressing device of the character described comprising a movable presser head and a' buck, the combination with hydraulic means comprising a cylinder provided with a piston of manual-ly operable means for effecting an actuation of said piston, a first means for transmitting motion from said piston to said presser head for a fraction only of the full stroke of said piston, means for progressively decreasing the pressure exerted by said piston during said actuation thereof whereby said presser head may be moved to a position closely spaced from said buck and held there under comparatively low pressure, a second means for transmitting motion from said piston to said presser head, said second means including means movable operatively to connect said piston with said presser head only when said head lies in closely spaced relation to said buck and means for thereafter effecting an operation of said piston under a comparatively high pressure.

7. In a pressing device of the character'described comprising a pair of relatively movable presser elements, a fluid circulating system, fluidoperated means in said system for moving one of said elements toward the other under pressure, a valve in said system and an operating handle therefor and means for operatively connecting said handle to the element moved by said fluidoperated means; said connecting means being so constructed and arranged that said valve is automatically operated progressively to decrease the pressure under which said one element is moved as it approaches the other element.

I HAROLD A. PERKINS.

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