US1323590A

US1323590A - Steam hydraulic intensifier

Info

Publication number: US1323590A
Authority: US
Publication date: 1919-12-02
Anticipated expiration: 1936-12-02

Description

T. W. HAND.

STEAM HYDRAULIC INTENSIFIER.

APPLICATION FILED JAN-19.1918.

1,323,590. Patehted Dec. 2,1919.

5 SHEETS-SHEET I.

ENVENTOR 44 l hwd T. W. HAND.

STEAM HYDRAULIC INTENSIFIER.

APPLICATION EILED JAN. 19. I918.

Patented Dec. 2,1919.

5 SHEETS-SHEET 2.

T. W. HAND.

STEAM HYDRAULIC INTENSIIIER.v

APPLICATION. FILED IAN. I9. I9l8.

5 SHEETS-r-SHEET 3.

INVENTQR Patented Dec. 2', 1919.

I. W. HAND.

STEAM HYDRAULIC INTENSIFIER- APPLICATION FILED IAN. I9. 1918.

Patented Dec. 2,1919.

5 SHEETS-SHEET 4 ENVENTO T. W. HAND.

STEAM HYDRAULIC INTENSIFIER.

APPLICATION HLED JAN- I9. l9l8- v Patented Dec. 2,1919.

5 SHEETS-SHEET 5 M, M 1 9 0 9 6 2 5 7 c M 9 M 9 J. t x M7 m w a 0 1 1 MM 1 W J 8 9 INVENTQ PATEN FFQE,

HOIVIAS WILTON HAND, OF SHEFFIELD, ENGLAND, ASSIGNOR TO DAVY BROTHERS LIMITED, OF SHEFFIELD, ENGLAND.

Specification of Letters Patent.

Patented Dec. 2, 1919.

Application filed January 19, 1918. Serial No. 212,550.

To all whom it may concern:

Be it known that I, THOMIAS lVILTON Hana, a subject of the King of Great Britain, and resident of Park Iron Works, Sheifield, in the county of York, England, have invented certain new and useful Imprcvemei'lts in Steam Hydraulic Intensifiers, of which the following is a specification.

This invention relates to steam hydraulic intensifiers of what may be termed the improved iiwerted type described in the specificationof the application for Letters Patent filed Aug. 20, 1917, Serial No. 187,271, according to which the steam cylinder of the intensifier is mounted above and in axial alinement with tile hydraulic cylinder while the movable member, whether ram or cylinder, of the hydraulic portion of the intensifier is placed lowest and connected with the steam piston by means of side rods,

the present invention improved mechanism is provided for cont-rolling the valve or valves whereby steam is admitted and exhausted to andfrom the steam cylinder of the intensifier and also to and from-the lifting cylinders of the hydraulic press (c.

y. forging press, shears or the likelwhich is uorked by the intensifier, the control'of the steam valve or valves of the intensifier being efiected conjointly by a handing-lever and by huntinggear actuated by the steam piston ofthe intensifier in such manner that the movement of said piston in perfornr ing its working stroke automatically causes the supply of steamto be out oif in accordance with the position in which the handinglever is held; while trip mechanism is interposed between the same handinglever and the steam valve or valves appertaining to the lifting cylinders for the purpose of automatically coupling and uncoupling said lifting cylinder valve or valves to and from the handing-lever insuch manner that steam is normally admitted to the lifting cylinders (so as to tend to raise the main press-head) but is exhausted therefrom duringthc earlier mart of the pressing strokes of the main lraulic ram of the press when the latter being worked with long strokes. Huntinggear employed for a similar purpose in what may be termed a non-inverted intensifier has heretofore comprised a floating lever coupled to the haadingdever. to the valve or (with the necessary lost motion) to the valves of the intensifier steam cyllnder, and a leverage-system connected with an inclined, movable, counterweighted control-bar, which bears against a roller moving as one with the steam piston of the intensifier; the initial inclination of this control bar being determined by the angular position to which the handing-lever is set for each stroke of the press, so that the supply of steam to the steam cylinder of the intensifier is cut off automatically at an earlier or a later point in the stroke of the steam piston in accordance with such position of the handing-lever. 7

According to the present invention an inclined or tapering cam-bar is fixed by its lower end to the lower end of the movable member whether ram or cylinder, of the hydraulic portion of the intensifier so as to move lengthwise as one therewith, and is offset from said member so as to be adapted to bear against one arm of a counterweighted lever having a stationary fulcrum; said lever being coupled to the handing-lever, and also to the trip-mechanism for operating the steam valve or valves ofthe lifting cylinders of the press, through the medium of a floating-lever which itself is coupled to the valve or (with the necessary lost motion) to the valves of the intensifier steam cylinder; the point in the stroke of the steam piston whereat the supply of steam is cut oil being thus determined by the setting of the hand-lever.

In the accompanying drawings, Figure 1 is a side elevation showing an example of an intensifier of the improved inverted type above referred to, to which the present view as seen from the right hand side of Fig. 1; 'Fig. 3 is a plan view, partly in sectional elevation of a preferred for-mot the hydraulic working-valve which controls the connection between the hydraulic invention is applied; Fig. 2 is a similar Cir main pressure pipe and the usual air-Vessel; and Fig. 8 is an outside elevation of the same valve, viewed as in Fig. 1.

In the example illustrated, the steam cylinder 11 of the intensifier is mounted upon a stool 12 which rests upon the foundation 13, and the stationary member of the hydraulic portion of the intensifier is the hydraulic cylinder 14'which is supported by the stool 12 so as to extend beneath and in axial alinement with the steam cylinder 11;

while the hydraulic ram 15, whichis fitted to work through a stuffing box 16 at the open.

lower end of the cylinder 14, carries at its lower extremity a crosshead 17 whereby the ram is coupled to the piston (not shown) within the steam cylinder 11 through the medium of a pair of

side rods

18, 18 which extend parallel with and on opposite sides of the comomn axis of the

cylinders

11 and 14 and ram 15, the

rods

18, 18 passing through stufiing boxes (not shown) in the bottom cover of the steam cylinder 11, and through

guides

19, 19 in the stool 12 (see Fig. 3). The hydraulic main orhigh-pressure pipe leads from an outlet 20 near the lower end of the hydraulic cylinder 14 to the main hydraulic cylinder (not shown) of the hydraulic press (a. g. forging press, shears or the like) workedby the intensifier;

this high-pressure pipe being in two sections, whereof the one section 21 extends from the cylinder 14 to the hydraulic working-valve 22 which controls communication between the hydraulic high-pressure pipe and the hydraulic low-pressure pipe 23 connected with the usual air vessel (not shown), while the other section 24 leads underground from the working-valve 22 to the main hydraulic cylinder of the press.

The cam-bar by-means of which, according to the present invention, the steam valves of the intensifier are controlled as already stated, consists of an upright, upwardly-tapering bar 25 fixed by its lower end 26 to the crosshead 17 so as to move vertically as one with the ram 15 and steam piston of the intensifier. One edge 27 of the bar 25 extends parallel with the direction in which the bar moves, and is guided by slid ing in contact with a grooved stationary roller 28 carried by a bracket 29 which is fixed to the cylinder 14 near the lower end of the latter, while a grooved roller 30 carried by a leverf'which may be termed the main lover (of the valve-gear) bears constantly against the opposite or inclined edge 31 of the bar 25 so as to be moved in one direction or the other as said bar travels upward or downward; a short portion 31 of the lower end of the edge 31 being formed with a steeper slope (see Fig. 1) so as to be adapted to cause the exhaust valve of the intensifier steam cylinder to open rapidly when the steam piston closely approaches the upper limit of its working stroke, as

hereinafter more fully explained.

The maln leverjust referred to is a threearmed lever whereof one arm 32 depends from the fulcrum of the lever and carries the roller 30 at its extremity, while the the main lever is represented by a horizontal rocking-shaft 36 journa-led in a bearing 37 (or bearings) on the stool 12, the arm 32 being fast on the inner end of the shaft while the

arms

33 and 34, which extend in one plane,.are fast on the outer end of the shaft beyond the stool 12. p

In the example illustrated, the supply and exhaust of steam to and from thesteam cylinder of the intensifier are controlled by double-beat drop-valves, and the supply and exhaust of steam to and from the lifting cylinders of the press are controlled by a single piston-valve, all these valves being mounted with the axes of their spindles extending-vertically in the plane wherein the

arms

33 and 34 of'the main lever oscillate.

38 is the main steam pipe serving to leat steam to the steam inlet valve 39 of the intensifier and alsoto the pistoirvalve 40 for controlllng the supply and exhaust of steam to the liftingcylinders of the press; the pipe 38 being connected to the body 41 of the valve 39abovethe latter. while a passage 42 leads from the valve-body 41, at a point below the seat of the valve 39, to the lower end of the steam cylinder 11 of the intensifier; A passage 43 leads from the valve-body 41, at a point above the seat of the valve 39,,to. the inlet ports in the body 44 of the piston valve 40 the pipe which leads from this latter valve to the lifting cylinders of'the press being connected to the valve-body 44 at 45.

46 is the steam exhaust valve of the in tensifier, the body 47 of which communicates both withthe passage42 by way of a passage 48 above the seat of the valve 46,

and also directly with the lower end of the (which is loaded by a weight 54), and the" spindle '55 of the exhaust valve 46, are respectively coupled by pin-and-

slot connections

56 and 57 to the opposite ends of a substantially horizontal lever 58 which is mounted to rock about a stationary fulcrum 59; while a link 60, attached to the lever 58 between the fulcrum 59 and point 57, serves to couple said lever to an intermediate point in the length of a floating lever 61 which extends in a substantially horizontal direction above the lever 58. One end of the floating lever 61 is connected with the arm 34: of the main lever through the medium of a lever 62 mounted to rock about a stationary fulcrum 63; one arm of this lever 62 being coupled to the arm 341 by means of an adjustable link 64 while the other arm of the lever 62 is connected with theiadjacent end of the fioatinglever 61 by means of a link 65 which extends in alinement with the exhaust valve spindle 55 and is connected thereto by a pin-and-slot 66. The other end of the floating lever 61 is connected with the handing-lever 67 through the medium of a substantially horizontal lever68 mounted to rock about a stationary fulcrum69; one arm of this lever 68 being directly connected to the adjacent end of the floating lever 61 while the extremity of the other or long arm is coupled'by an adjustable link 70 to an arm 71 fast on the shaft 72 of the handing lever.

At an intermediate point in its length, the long arm of the lever 68 has attached to it a vertical rod 73 which, depending in axial alinement with the stem 7a of the piston valve 40, is detachably coupled thereto by trip mechanism. This mechanism 7 comprises an upright socket 75 pivoted at 76 to the valve stem 7 1 and serving as a guide for the rod 73 which is formed with a lateral notch 77 '(Fig. 6); and a latch-bolt 78 which tends under the pressure of a spring 79 to engage the notch, but is controlled by means of a bell-crank lever 80 pivoted at 81 to the socket 75, this lever 80 being connected by a slotted link 82 with a stationary abutmentpin 83. The arrangement is such that when, during the working of the press with long strokes, the handing-lever 67 (which is shown as resting in normal position) has been moved a certain distance toward the right-hand in Figs. 1 and 5," so as to depress the long arm of the lever 68 to the full extent, the consequent descentof said arm will bring the notch 77 of the rod 7 3 into position to become engaged by the latch-bolt 78. Hence, when the handing-lever is afterward moved toward the left, the consequent ascent of the long arm of the lever 68 will raise the piston valve 40 along with the rod 73 until the exhaust port 84 of said valve is open to the

exhaust pipe

51, 49. Just before the handing-lever reaches a certain 1 ntermediate position, the slotted link 82 Wlll be arrested by the pin 83 so as to cause the bell-crank lever to withdraw the latch-bolt 7 8 from the notch 77, whereupon the pistonvalve a0, which is loaded by a dependent weight 85, will drop back to the normal position shown, wherein its steam-inlet port 86 is open to the passage 13 and main steamv pipe 38; in which position the valve 10 remains throughout the rest of the throw of the handing-lever 67 toward the left, and thus maintains a cushion of live steam beneath the pistons of the lifting cylinders of the press 50 long as steam is admitted to the main steam pipe 38.

The type of hydraulic working-valve 22 which is illustrated in the drawings is a compound or pilot-controlled valve, and is seen in section in Fig. 7, wherein the

pipe connections

21 and 24 are shown as extending at right angles to the direction in which they extend in Figs. 1 and 5. The valvebody 22 has a central chamber 87 into which 7 the

pipes

21 and 24 open from opposite sides,

these pipes respectively leading, as alreaoy stated, from the hydraulic cylinder ll of the intensifier, and underground to the main hydraulic cylinder of the press, while the pipe 23, leading underground to the airvessel, opens from the bottom of the chamber 87. The main working-valve itself consists of a substantially cylindrical plug 88 which normally rests, as shown at 89, on a mitered seating around the mouth of the pipe 23; the plug 88 being of less diameter than the chamber 87 so as to leave the communication between the pipes 21 and constantly open. The plug 88 has a central chamber 99 into which lateral ports 90 lead so as to enable communication to be established between the pipes 21 and 2-1 and a passage 91 which leads downward through the plug 88; this passage 91 being normally closed by a pilot-valve 92 which is slidable vertically through the plug 88 and which normally rests, as shown at 93, on a mitered seating around the mouth of the passage 91.

The plug 88 is not mechanically connected to any operating part, and lifts only when, owing to the main press-head and the intensifier ram descending by ravity, the pressure within the pipes 21, 24: ecomes less than that within the air vessel and pipe 23; the function of the plug being to then open automatically and permit the pipes 21, 2 1 to become promptly filled with water from the air vessel. A spring as is coiled in compression about the stem 95 of the pilot-valve 92 between a nut 96 on the stem and a stationary bridge 97 secured to the valve-body 22 by pillars 98; the function of this spring 94 being to cause the pilot-valve 92 to close when permitted. to do so, against the hydraulic pressure acting upon the full area of its lower end as compared with the pressure upon its upper end less the area of the valve-stem 95. The pressure within the space 100 above the plug 88 and pilot-valve 92 is maintained constantly equal to that within the pipes 21, 2 1 by means of a duct or ducts 101 leading into said space from the chamber 87. The pilot-valve 92 is raised against the stress of the spring 9 1 by means of a lever 102 the bifurcated end of which engages beneath the nut 96; this lever, which is mounted to rock about a stationary fulcrum 103, being coupled by an adjustable rod 10% with pin-and-slot connection to a short arm 105 fast on the shaft 7 2 of the handing-lever 67.

The improved apparatus as a whole is worked in substantially the same manner as the similar apparatus employed in connection with a non-inverted intensifier and will therefore be explained hereinafter in more general terms. It will be understood that during resting conditions a. with the handing lever 67 standing in the mid position shown, the steam valve 39 and exhaust valve 4:6 of the intensifier both closed, the piston valve open to admit steam beneath the pistons in the lifting cylinders of the press, the'working-

valve

88, 92 closed, the hydraulic ram of the intensifier at the bottom of its travel, and the .tool of the press resting on its anvil), the press-head will not be raised although steam be admitted beneath the pistons of the lifting cylinders, for the reason that the hydraulic main pressure pipes 21 and 2%, as well as the hydraulic cylinder l l of the intensifier and the main hydraulic cylinder of the press, are all filled with water.

If, now, it be desired to set the press in operation, the water in the hydraulic main pressure pipes 21 and 2 1 must first be af forded freedom to escape so as to enable the steam pistons of the lifting cylinders raise the main ram of the press sufficiently to accommodate the work on the anvil. This is effected by opening the pilot-valve 92; for which purpose the handing-lever 67 must be moved toward the right in Figs. 1. and 5 so far as to cause the bifurcated lever 102 to open the pilot-valve 92 and thus afford freedom for the water in the

pipes

21 and 24 to escape to the air-vessel by way of the passage 91 and pipe as the main ram rises under the pressure of the steam in the lifting cylinders. While this is taking place, the plug 88 of the working-valve re mains seated owing to the rise of the main ram producing in the

pipes

21, 24% a pressure higher than that in the air vessel and pipe 23. When the main ram of the press has been raised suiiiciently, the return of the handing-lever 67 to its mid or neutral position will allow the valve 92 to close and cut oil communication between the air-vessel and the pipes 21 and 24:.

The nature of the subsequent movements of the handing-lever 67 will depend upon Whether it is desired to work the press with long and comparatively slow strokes, or with short and rapid strokes. If short, quick strokes are required, the: piston valve &0 must remain open to steam, so as to maintain a cushion oflive steam beneath the pistons of the lifting cylinders; and for this purpose the oscillations manually imparted to the handing-leverinust be kept within the limits of that are of its throw wherein the rod .78 fails to descend so far as to bring about the engagement ofthe latch bolt 78 with the notch 77 and the consequent opening of the valve 40 to exhaust as the rod 73 rises. "With this proviso, the movements given to the handing lever 67 in rapid working with short strokes are substantially the same as those imparted to it in working with long strokes, except in the following respects.

That is to say, when it is desired to work the press with long and relatively slow strokes, it is necessary to open the lifting cylinders to exhaust at the be inning and during the earlier part of the working stroke of the press, so as to allow the presshead to drop and prevent its again rising before the pressing stroke commences. 'For this purpose, at the commencement of each long pressing stroke, the handinglever 67 must be moved over to, or near, the right hand limit of its throw so as to insure that on its return movement toward the left the rod 7 3 in rising will openthe valve 4:0 to exhaust until the latch-bolt 7 8 becomes dis engaged from the notch 77, which happens at about that angular position of the handing-lcver where-at the steam valve 3., of the intensifier is opened. The dropping of the valve e0 at about this moment insures'the provision of a cushion oflive steam beneath the piston of the lifting cylinders in time to cause-the press-head to rise promptly at the termination of the long pressing stroke.

It will be observed that the steam and exhaust valves. 39 and 16 are respectively opened, according asthe handing-lever 67 moved toward the left ortheright of the mid or neutral position wherein it is shown in Figs. 1 and 5; the long arm of the lever 68 being raised or depressed to a cogrespondingextent. According as said arm is, raised or depressed, the floating lever 61 is depressed or raised about its point of attachment to the link 65, and through the link 60, rocks the lever as to open the steam 1 'alve 39 or the exhaust valve 16; the'provision of the pin-and-slot connections at 56 and 57 insuring that the open ing orclosing of either valve will not necessarily affect the position of the other.

When the handing-lever is moved to and held in a position toward the left of its new tral position so as to "open the steam valve 39 to any desired extent, the consequent ascent of the hydraulic ram 15 will carry up with the-latter the cam-bar :25, which will force tow rd the left the arm 32 of the main lever and, by depressing the link 6-1, will raise the link 65 and impart to the floating lever 61' an upward angular movement about its point of attachment to the lever 68, which is meanwhile held stationary by the handing-lever. The pin-and-slot attaclnnent at 66 prevents the rise of the link 65 from lifting the spindle 55 and opening the exhaust valve 4E6; but the upward movement of the floating lever 61 raises the link 60 and causes suchangu-lar movement of the lever 58 about its fulcrum 59 as to permit the steam valve 39 to close under the load of its weight 5 1, which happens at the moment when the steam piston of the intensifier, and therefore also the ram 15 and cam-bar 25, have reached a point in their upward stroke corresponding to the angular posi-' tion in which the handing-lever 67 is held. When the steam piston" closely approaches the upper limit of its working stroke, the roller is engaged by the steep portion 31 of the inclined operative edge 31 of the cambar 25, so that not only is steam cut off by the closure of the steam valve 39, but at the sametime the exhaust valve 46 is quickly opened to relieve the pressure beneath the steam piston and thus assist in the arrest of the latter before it can come in contact with the top cover of the cylinder 11.

The whole of the above leverage-system, with the exception of that arm 32 of the counterweighted' main lever which bears against the cam-bar 25, preferably extends and moves in one plane as shown, so as, by obviating any tendency of the levers to cant laterally, to enable the use of way-shafts with duplex levers (involving the fitting of keys) to be dispensed with. Hence the fulcrum-pins of the valve lever 58 and intermediate levers-62 and 68 can be made fixtures in a single bracket 106 bolted to the stool 12 which supports the steam cylinder 11, whereby accuracy of adjustment is fa cilitated; while the elimination of the movable control-bar, formerly used, reduces the liability to defective action consequent on vibrations set up in the valve-gear; anylink connections adapted to afford the necessary lost motion.

Having now particularly described and ascertained the nature of my said invention and in What manner the same is to be performed, I declare that what I claim is 1. In a steam. hydraulic intensifier of the kind referred to, the combination of a steam cylinder, hydraulic ram, and mechanism for effecting control of the admission of steam to the steam cylinder jointly by a handing lever and by hunting gear, comprising a cam bar fixed to the movable ram member and having an inclined edge, a lever adapted to bear constantly against said inclined edge of the cambar, and a floating lever so coupled to said firstanentioned lever and to the valve of the steam cylinder that the point in the stroke of the steam piston whc'reat the supply of steam is cut ofi will be determined by the angular position of the hand lever.

2. In a' steam hydraulic intensifier of the kind referred to, the combination of steam cylinder, a hydraulic ram, and mechanism for effecting control of the admission of steam to the steam cylinder jointly by a handing lever and by hunting gear, comprising a cam bar fixed to the movable ram member and having an inclined edge, a lever adapted to bear constantly against said inclined edge of the cam bar, and afloating lever so coupled to said first-mentioned lever and to the valve ofthe steam cylinder that the point in the stroke of the steam piston whereat the supply of steam is cut off will be determined by the angular position of the handing lever.

3. In a steam hydraulic intensifier of the kind referred to, the combination of a steam cylinder, a hydraulic ram, and mechanism for effecting control of the admission of steam to and from the steam cylinder ointly by a handing lever and by hunting gear, comprising a cam bar fixed to the movable ram member and having an inclined edge, a counterweighted lever adapted to bear constantly against said inclined edge of the cam bar, and a floating lever so coupled to said counterweighted lever and to the valve of the steam cylinder that the point in the stroke of the steam piston whereat the supply of steam is cut oil will be determined by the angular position of the handing lever.

4. In steam hydraulic intensifier of the kind referred to. the combination of a steam cylinder, a hydraulic ram, and mechanism for effecting control of the admission and exhaust of steam to and from the steamcylinder jointly by a handing lever and by hunting gear, comprising a cam bar fixed to the movable ram member of the hydraulic portion of the intensifier and having an inclined edge, a lever adapted to bear constantly against said inclined edge of the cam bar and a floating lever so coupled to the handing lever and to said firstmentioned lever and to the valves of the steam cylinder that the point in the stroke of the steam piston Whereat the supply of steam is cut ofi" and the exhaust valve opened Will be de termined by the angular position of the handing lever.

5. In a steam hydraulic intensifier of the kind referred to, the combination of a steam cylinder, a hydraulic ram, and mechanism for effecting control of the admission of steam to the cylinder of the intensifier, a cam bar fixed to the movable ram member of the hydraulic portion of the intensifier and having an inclined edge, a lever adapted to bear constantly against said inclined edge of said cam bar, a handing lever and a floating lever coupled to said first-mentioned lever and to the valves of the steam cylinder, a valve controlling the lifting cylinders of the press, and a trip mechanism between the hand lever and said valve controlling the lifting cylinders.

6. "In a steam hydraulic intensifier of the kind referred to, the combination with a steam cylinder and a hydraulic ram, of mechanism for effecting the control of the admission and exhaust of steam to and from ing an inclined edge, a lever adapted to bear cam bar fixed to the movable member of the hydraulic ram and having an inclined edge,

a lever adapted to bear constantly against said inclined edge, a steam valve and connections between the same and said lever, the terminal portion of the inclined edge of said cam bar having a steeper slope than the main portion thereof, so as to be adapted to cause the exhaust valve of the steam cylinder toopen rapidly as the steam piston closely approaches the upper limit of its working stroke.

8. In valve controlling mechanism for the steam hydraulic intensifier.the combination of a steam cylinder, a hydraulic ram, a cam bar fixed to said movable member of said hydraulic ram and havingan inclined edge, a valve of thesteam cylinder, and a lever adapted to bear constantly against the inclined edge of the cam bar and connected to said valve, the terminal portion of the inclined edge of the cam har having a steeper slope so as to be adapted to cause the exhaust valve ofthe steam cylinder to open rapidly as the steam piston closely ap- ,7

proaches the upper stroke.

THOMAS WILTON HAND.

limit of its Working