US2010703A

US2010703A - Quenching press

Info

Publication number: US2010703A
Application number: US640674A
Authority: US
Inventors: Leon D Slade; Warner T Cowell
Original assignee: Gleason Works
Current assignee: Gleason Works
Priority date: 1932-11-01
Filing date: 1932-11-01
Publication date: 1935-08-06
Anticipated expiration: 1952-08-06

Description

Patented Aug. 6, 1935 PATENT OFFICE QUENCHENG PRESS Leon 1). Slade and Warner T. Oswell, Rochester,

N. Y., assignors to Gleason Works, Rochester, N. Y., a corporation of New York Application November 1, 1932, Serial No. 640,674

18 Claims.

.The primary object of the present invention is to provide a quenching press in which a substantially uniform initial quenchcan be produced whereby substantially uniform results may Lil be obtained in the quenching operation.

7 r, Further objects of theinvention are to provide a quenching press in which the articles to be treated can be centered more accurately, in which without use of any more power, a greater pressure can'be applied to the articles during quenching, and in which there are no moving parts under the quenching fluid so that water can be used just as satisfactorily as oil for a quenching medium. To these ends, it is a purpose of the invention to provide a quenching press in which the quenching operation is effected by passing a liquid over the article to be quenched instead of immersing it in a liquid and in which, conse quently, the article to be treated can be secured on a fixed support or die.

Another object of the in ention is to provide a quenching press in which the article to be treated is clamped by pneumatic pressure during the quenching operation and a liquid is used for the quenching medium and in which the clamping and quenching operations are controlled from a single valve. q

A further object of the invention is to provide a quenching press in which the flow of the quenching medium is'controlled from the operation of clampin the article to be quenched so that the article must be first heldrigidly against distortion before the quenching medium can flow around the article. v V

Still another object of the invention is to provide a quenching press in which the amount of liquid required for the quenching operation is reduced to a minimumand the flow of, the liquid is shut off automatically as soon as the article being treated is released.

' Other objects of the invention will appear hereinafter from the specification and from the reright angles to the plane of the drawing in Figure 1; and

Figures 3 to 6 inclusive are sectional views showing, respectively, possible forms of a small reducing valve, of a whistle valve, of a large reducing valve, and of an air-operated pressure regulator which may be employed on the press.

The quenching press illustrated in the drawings is made in two main sections, a lower section or base .lEl and an upper section or standard H. The base is hollow and a container or chamber 52 is mounted centrally therein. This container isadapted to hold compressed air under pressure. It issecured to the base it of the press by bolts l3 and its upper end is closed by a plate Hi that is held in place by bolts IS.

The base is formed with an integral chamber I6, the side walls I? of which are spaced from the outside walls is of the base. Openings 2!? are cut at spaced intervalsin the side walls ll of the chamber It so that the chamber l6 communicates with the hollow chamber 22 that is enclosed by the outer walls of the base and is formed between the walls H and I8.

At some distance above the top'wall 23 of the chamberlt, the base is provided with an integral internal flange or ring 24. There is a supporting plate25 secured to the flange 24 by screws 25. This supporting plate 25 carries the seat member 21 and this in turn carries a plate 23. The plate 28 carries a single ring member or the plurality of nested ring members 29 which constitute the lower die supporting the article to be quenched. The lower die also carries the expansible gripping device which is adapted to engage the bore or interior of the article to be quenched to'hold the article true during the quenchingoperation.

In the drawings, We have shown the press arranged to quench a spiral bevel gear G and the expansible gripping device may be made of a plurality of independently movable segmental grippers 38 oi the same type as described in the patent to Leon D. and Alton P. Slade, No. 1,166,307 of January 26, 1915.

The supporting plate '25 and the rest 21 are each provided with a circularly arranged series of openings, thc openings in the supporting plate being designated at 32, while those in the rest 2'! are designated at 33. Each opening 32 in the supporting plate 25 aligns with an opening 33 in the rest 21. The plate 28 is provided with aicircular series of openings 36, which are much smaller in diameter than the openings 33, but which communicate withthe openings 33. The

plate 28 and the lower die members 29 are also i.

provided with a series of communicating radial slots 37 which communicate with the openings 36. The slots fil lead in under the gear to be quenched so that the quenching medium can flow from the chamber 22 through the openings 32, 33 and 36 and ducts 3? in under the gear.

The supporting plate and rest are also provided with central openings 34 and 35, respectively, which align with one another and with the central opening 33 formed by the segmental grippers 36, when assembled. Hence the quenching medium can also flow from the chamber 22 through the openings 34, 35 and 39 over and around the gear.

The base it is formed at its topwith an annular ring or flange 48. This is spaced far enough above the flange 2d so that a well is formed in the base which contains the lower die, the expansible gripping device and the gear to be quenched.

The standard it is secured to the flange lil above the well 32 by bolts ii. The standard it carries a cylinder M, which is secured in place on the standard by bolts id. The upper end of the cylinder 53 is closed by an end-plate t5, which is secured in position by screws it, while the lower end of the cylinder is closed by an endplate dl which is secured in position by screws 38.

There is a hollow piston 58 mounted in the cylinder 53 to reciprocate therein. The upper end of this piston 55 is closed by a plate 52 that is formed with a central recess. The end-plate 35 that closes the upper end of the cylinder 33 is provided with a central tubular projection 53 through which compressed air is supplied to the upper end of the piston 59 to move the piston downwardly in the cylinder. The projecting conductor 53 of the plate Q5 is received in the central recess of the plate 52 when the piston 59 is at the upper limit of its movement in the cylinder 43. The piston-rings 54 which prevent leakage of air along the piston Eli are held in place by the ring 55 which is secured to the piston by screws 56. The plate 52 is held in position by screws 53. r

'The lower end of the piston 53 is closed by a plate 63. This plate fill is formed at its lower end with a seat for the die-support 62. The plate (ill and die-support 62 are secured to the piston 59 by screws 63.

The upper die 8! is secured to the lower face of the die support 82 by bolts 65. This upper die will be shaped, as is the usual practice, to engage the upper end or face of the article to be quenched.

The upper die support 62 has a conical outer surface and is centrally bored to provide a cylinder 66. The piston til is mounted in this cylinder to reciprocate therein. The plate 65 closes the upper end of the cylinder while a plate 68 is secured to the lower face of the support '32 to limit downward movement of the piston Bl in the cylinder 56. The plate 58 is held in position by screws 69.

A tapered expander it? for operating the grippers 36 is secured in any suitable manner to the piston Bl. A centering stud it, that has a pressed fit in a recess inthe plate t9, extends centrally through aligned openings in the piston 67 and expander 76.

There is a plate 7 5 spaced below the plate ll and secured thereto by studs 75. This plate serves as an outboard guide or support for th piston 5!) in its movement.

The pistons 58 and 6? are preferably operated by pneumatic pressure, while a liquid medium is employed for the quenching operation. The manner in which the piston 56 is actuated and the manner in which the quenching medium is applied to the gear or other article to be treated will now be described.

Compressed air is supplied to the press from any convenient source through the pipe 86 (Figure 1). At the press, the compressed air passes first through a strainer H which may be of any suitable construction and which is designed to remove dirt or grit from the air line.

After leaving the strainer 35, the air line divides. Part of the air passes through the T 82 and connecting piping into a large reducing valve 8 (Figures 1 and 5) and part passes from the T 32 through the pipe 85. The reducing valve 84 controls the pressure exerted by the upper die on the body of the gear or other article being treated.

The reducing valve 84 may be of any suitable construction. A valve of one standard make is illustrated simply as an aid to a better understanding of the operation of the press.

The compressed air enters this reducing valve 84 through the duct 3'1. The inner end of this duct is normally closed by the valve 85 that is carried by a double-armed member 89. The member 89 is secured at its upper end to a flexible diaphragm $8. held shut by the action of the coil springs 92 and t3, the tension of which can be adjusted by the screw S t. A more detailed description of the construction of the valve need not be given here, since the valve forms no part of the present invention. As long as the pressure in the air line is great enough, the valve 38 is held open and the air can flow from the reducing valve line 8i out of the port 95 into the line 93-3.

The valve St is connected by the pipe 93 and the T Sl with a standard pressure gage S8. The pressure of the air flowing from the reducing valve8 l is recorded on this gage and hence the gage can be used to determine the pressure at which the reducing valve can be adjusted to open.

From the T 9'7, "the compressed air flows through the pipe 99 to a four-way valve tilt which may be of any suitable construction. This valve is operated by the lever Hill. It is connected by the pipe 192 with the lower end of the cylinder 43 and by the piping $18 3 with the upper end of this cylinder. The fourth line E55 leading from this valve is an exhaust line and may either be opened to the air or be connected to the compressor employed to compress the air for use in the system.

When the lever Hill is turned in one direction, pressure is applied to the upper end of the piston 58 to lower the upper die it upon the article to be quenched, and when the lever Eel is reversed, pressure is applied to the lower end of the piston 53 to raise this piston in the cylinder 3 and withdraw the upper die from engagement with the work.

The upper end of the piston Si is always on pressure when the machine is in use. The compressed air is conducted to the upper end of this piston from the line 85 already referred to, through the connection Hill, the line i i i, a small reducing valve H2, and ducts E25, E26 and H2 1, to which further reference will be made hereinafter.

This reducing valve H2 may be of any suitable construction. One possible construction is shown in Figure 3. in which there is illustrated The valve 88 is normally close the valve proper H3.

the construction of a standard valve now incommon use. This valve controls the pressure exerted on the bore of the gear or other article bein quenched. The valve is normally open, the valve proper H3 being normally held off of its seat H4 by the pressure of the coil spring II 5 that operates against a. flexible diaphragm M6 to which the stem of the valve H3 is connected. The tension of the spring H5 can be adjusted by manipulation of the screw H8.

There is a pressure gage I28 of standard construction connected to the valve H2. This gage records the pressure of the air passing through the valve II 2. By adjusting the screwH8 and checking against this gage, the valve Hi can be.

adjusted so that the proper-pressure is secured on the upper end of the piston 51. If the pres sure entering'the valve chamber H2 is excessive, the pressure of the air on the diaphragm I will The air may enter the valve chamber H2 at I22 and leave through the opening I 23.

The valve H2 is connected with the gage I25 by the T I25. This T is connected with a second T I25 and this latter T is connected through operation, the filled with air under a definite pressure and the chambers I6 and 22 in the base will be filledwith oil or water or whatever quenching liquid is employed in the press. When the piston 56 has descended and the upper die 54 is exerting such a pressure upon the body of the work and the grippers 3!! such a pressure upon the bore of. thework as to hold the gear against distortion, the air in the chamber i2 is discharged into the chamber I5. In the chamber I2, this air will have been under a very high pressure. In the chamber I5 it will expand rapidly and will rapidly force the quenching liquid from this chamber and from the chamber 22 up through the openings 32 33-45 and 345535 in and around the gear to be quenched, producing an initial drastic quench.

The supply of air to the chamber I2 is controlled by a whistle valve which may be of any suitable construction. One possible construction is shown in section in Figure 4. This valve,

which is designated at I35, is operated by the upper die support 62 in its movement. The operating lever I36 of the valve is arranged to engage the conical outer surface of the upper die support. The coil spring I 31 operating on the valve I38 proper tends to keep the valve closed. When the piston 55 is raised to the upper limit of its movement, however, the lever I is rocked about its pivot I39 and the nose I40 of thislever through its engagement with the valve stem I4I forces the valve E38 open. This allows air to flow into the chamber I2. When the upper die support 62 descends, however, the valve is again I closed by the spring I31 and the supply of air to the chamber I2 is shut off.

The air comes to the valve I35 through the identical in construction with the valve H2 and v the lines I46 and I41.

the press through the pipe-line I13.

the chamber I2 through the lines I48 and I49, the T I55, and the lines I5I, I52, I53, I54, I55, and I56, and the duct I51. The duct I51 is drilled in the bottom Wall of the chamber I2. The pressure reducing valve I controls the pressure of the air in the chamber I2. A standard pressure gage I58 which is connected to the T I55 records the pressure in the chamber and is used to adjust the valve I45 to secure the desired pressure.

The flow of air from the air-chamber I2 into the liquid chamber I6 is controlled by a directacting three-way valve I65 which may be of any suitable construction. The valve shown in section in the drawings is connected by the lines 15! and IE2 with the line I55, already mentioned, that leads into the chamber I2. The valve I55 is also connected by a line I53 with a pipe E54 that is mounted in the upper part of the chamber I6. The pipe 64 is provided with a plurality of holes or openings I55 through which air can escape into the chamber I5 when the air chamber I2 is con nected with the chamber I6. The third line I61 leading from the valve I66 is an exhaust line.

The valve I55 comprises the valve proper I15 whose stem threads into a head 12. A coil spring 1' i3 which surrounds the valve stem serves to normally hold the valve I16 against its upper seat, as shown in the drawings, thus closing the line 55! and connecting the line I63 with the exhaust line I51. The valve I is adapted to be e erated by air pressure. When compressed air under sufficient pressure is admitted into the valve E51! above the head E12, the valve I15 is forced down ward, opening the line I BI and closing the line I61. This puts the line I63 on supply frcrnthe line I6I. The structure and operation of the valve I50 need not further be described because such valves are well known and the valve itself forms no part of the present invention.

The supply of quenching liquid to the chambers I5 and 22 is controlled by a direct-action threeway valve I15, which may be larger than the valve I but of similarconstruotion. The supply of.

quenching liquid comes to the press from any suitable source, as a tank or reservoir, through the pipe-line I11. The quenching liquid enters This line as does the linel53, threads into the plate are that closes an opening in one side wall I8 of the base of the press and that forms part of one side wall of the chamber I6. The plate I15 is secured in position by bolts I80.

j The third line from the valve I 15 is an exhaust line comprising the piping I82 and I53. The two lines I61 and 83 are connected by a T I84. This T is in turn connected through suitable connections with the main exhaust line I85.

The coil spring I81 which surrounds the stem of the valve proper E88, serves to normally hold the valve I88 in the upward position shown in the drawings with th line I18 cut off from supply. The valve I15 is intended, however, to be operated by air pressure and when a sufficient pressure is applied to the head I85 of the valve stem, the valve proper I88 is forced down from its upper seat to its lower seat, thus opening he line I15 to supply from the line I11 and closing the exhaust line I82.

' The valves I and I15 are intended to be operated by pneumatic pressure built up in the cylinder 43 after the upper die 54 has engaged the work. .There is a line I95 which is connected to a T191 that is incorporated in the line I04. The

lFrom the whistle valve I35, the air passes to,

I the stem of a valve 28! which is kept closed by the coil spring 282.

The valve 2% controls communication between a line 222 and a line 268. The cam I9? is adjustable by rotation. to determine what amount of pressure on the capsule 2% shall be required in order to open the valve 2M. For convenience in adjusting the cam till, the regulator I96 is provided with a hand 2% (Figure 1) that is secured to the shaft that carries the cam ISI. This hand 22 5 reads against a graduated dial on the gage.

The amount of pressure in the lines I9ii--I95 is recorded by the gage 296 which may be of standard construction and which is connected to the T I92.

When the pressure in the line I95 is great enough to open the valve 20 I, the compressed air passes from the line 85 through the connection I90, the line 2H3, a pressure reducing valve 2I2, which may be of the same construction as the valve M2, the lines H3 and 202 to the line 283. The pressure in the lines 2 I3 and 262 is determined by the setting of the pressure reducing valve 2 I2 which is recorded on the gage 2I5. This gage, which may be of standard construction, is connected to the lines EIIl and 2I3 by the T MS.

The compressed air entering the line operates a direct-acting three-way valve 225), which is smaller than the valves Iiill and I'I5, but which may be similar in construction to them. The spring 222 of the valve 229 normally acts to shut oil connection between the lines 22 and When the valve 2M is opened, however, the compressed air flowing from the line 2Il2 through the line 223 will operate the valve 22@ against the resistance of the spring 222 and the lines 223 and 225 will be connected. Then the compressed air flowing from the line 2H3 through the T into the line 224 will pass into the line 225 and through the

lines

226 and 227, which are connected with the line 225 by the T 228, to the valves its and W5, respectively.

The pressure in the line 224 is determined by the adjustment of the reducing valve BIZ and can be read on the gage 2L5 which is connected to the lines 2 IE! and 2 I3 by the T 2 E5. The reducing valve 2 I2 will be adjusted so that sufficient pressure will be obtained in the line 224 and, therefore, in the lines 226 and 22l to operate the valves I65 and H5, respectively, while'protecting these valves against excessive pressure.

The valve 22 is closed at its bottom by a plug 229 and there is no exhaust line leading from this valve.

To use the press, the operator selects a lower die 29 whose upper surface is shaped to conform to the shape of the lower face of the gear or other article to be treated. Likewise, an upper die Ed 'is selected, shaped to engage the upper face of the article to be treated. The two dies serve to press and to hold the article in correct shape during the quenching operation. The grippers 32 are selected in accordance with the diameter of the bore or of the interior of the gear or other article to be quenched.

Before using the press, the operator also adjusts the valves H2, I35, 8G, M5, I96 and H2. The valve I I2 is adjusted in accordance with the maximum pressure which it is desired to have exerted on the bore of the gear during the quenching operation. The relief valve ISI is adjusted to blow off at a pound or so above this maximum pressure. If too great a pressure is applied to the bore of a gear during hardening, the bore will open up in the hardening. The valve 8 is adjusted in accordance with the pressure which it is desired to have exerted on the body of the gear by the upper die. This pressure wants to be high enough to press and hold the gear in correct shape. The valve M5 is adjusted in accordance with how drastic an initial quench is desired, for the adjustment of this valve predetermines the maximum pressure of the air in the chamber I2. This pressure is naturally varied for gears of different section and different diameter.

The valve I95 predetermines the pressure which it is desired to have exerted on the body of the gear before the valve Ida can be opened to allow the air to pass from the chamber I2 into the liquid reservoir It. The valve 2 I2 acts simply as a safety valve to prevent too high a pressure being applied to the valves 22%, I68 and Ill). These valves are built to open at a definite pressure and an excessive pressure might have a deleterious effect upon them.

Assuming that the air-chamber I2 has been filled with air under a predetermined pressure and that the reservoirs It and 22 are filled with quenching liquid, the press is ready for operation.

In the operation of the press, the article to be treated, such as the gear G, is first placed, while hot, upon the lower die 29. The operator then turns the lever I55 of the four-way valve I08 so as to admit compressed air into the cylinder l3 above the piston 5i! and at the same time to put the lower end of the cylinder Gt on exhaust. This causes the piston 53 to descend in the cylinder Q3 and lower the upper die upon the work.

As previously stated, the upper end of the piston 3? is always on pressure from the supply line 85 through the linesand III, the reducing valve M2, the Ts I25 and I26, the piping I2? and the duct I28. Thus, as the piston 5d descends, the pilot member l2 and taper expander Ill will come into engagement with the grippers 3% before any substantial pressure-is exerted by the upper die upon the gear. The pilot 22 serves to center the grippers 3E and the expander "IE3 serves to expand them to engage the bore of the gear and round the same up. As the piston 59 continues to descend, the small piston 8'5 will be forced upwardly in its cylinder 56 against the resistance of the air. This will build up pressure in the upper end of this piston. This built-up pressure will hold the expander in operative position throughout the quenching operation, but if the pressure rises too high, the relief valve I3l will blow o-if.

When the upper die comes into contact with the body of the gear, the large piston Ell is stopped.

This causes pressure to be built up in the upper end of the cylinder 3 and in the lines I04, I90 and IE5. When this pressure is great enough, it will operate the pressure regulator I96 opening the valve 29 I, thus permitting the compressed air to flow from the supply line 88 through the lines 85 and 2E3. the reducing valve 2E6 and the lines 2 292 and 263 to the three-way valve 228. This causes this valve to be opened so that the compressed air can flow fromtheline 2I3 through the lines 224 and 225 to the lines 226 and 221 through the openings I65 causes the quenching liquid to be forced out of the reservoirs I6 and 22 through the openings 32, 33 and 36 and the slots 31 under the gear and through the openings 34 and 35 and the opening 39 between the expander members 30 to how between the teeth of the gear. Thus the hot gear is quenched and hardened.

The rush of air from the chamber I2 into the chamber i6 is so rapid, when the valve I68 is opened, that the quenching liquid in the reservoirs I6 and 22 is very rapidly forced around the gear and an initial drastic quench is the result. The set of the gear in a quenching operation is of course produced by the initial quench. With the present press, a uniform volume of liquid is moved by a uniform volume of air toeffect the initial quench. Hence uniform results are naturally obtained.

The valve I15 is opened atthe same time as the valve I66 so that quenching liquid can flow into the press from the line I11 through the line' I18. In use, the upper die is allowed to remain down for a substantial period after the initial drastic quench and the liquid entering the press from the pipe I11 flows up around the gear and thoroughly cools it. ,The liquid which flows around the gear after the initial quench has, however, no appreciable effect on the hardness or internal structure of the gear. The set of the gear, as stated before, is produced by the initial drastic quench.

The overflow liquid from the well 42 is carried away through the pipe 236 which is connected to the well and which leads back to the tank from which the liquid is drawn by the pipe I11.

After the gear has been sufiiciently cooled, the operator reverses the lever IUI, thus putting the lower side of the piston 50 on supply and the upper side on exhaust. The lines I90 and I95 being connected to the line IE4 are also put on exhaust with the result that the valve 2III is closed by the spring 205. The valves I and I15 are therefore closed under actuation of the springs I13 and 81, respectively. Thusthe flow of the quenching liquid into the press is shut off as soon as the upper die starts to leave the work and the air in the lower part of the press is exhausted from the reservoir I6 through the pipes I64, I63, I61 and I35. s

The whistle valve I35 will have remained closed during the descent of the upper die upon the gear and during the timeof quenching, but as the piston 56 rises, the conical outer surface of the upper die support 62 engages the operating lever I36 of the whistle valve, forcingthe valve open against the resistance of the spring I31.

This enables the chamber I2 to be refilled with compressed air, for When the whistle valve is open, the compressed air will flow from the supply line 8!! through the lines 85, I46, I41, I48,

-I5I, 552, I53, I54, I55, and IE5 and the duct I51 into the chamber I2. The whistle valve remains open as long as the piston 50 is in its upper poof a stationary lower die.

sition, as illustrated in Figure 2. The pressure of air in the chamber I2 is gOVerned. by the adjustment of the reducing valve I45. This valve closes the line to the chamber I2 from the supply line 80 when the pressure ofair in the cham- 1 her I2 is at the operating pressure desired.

When the piston 58 has been raised far enough, the hardened gear can be taken out of the press and another hot gear put in its place to be quenched.

The skirt 232 that is secured to the upper die support 62 by screws 233is for the purpose of confiining the quenching liquid about the gear during the quenching operation, so as to secure the maximum cooling effect from this liquid;

It cooperates for this purpose with the rest 21.

By constructing the press so that the valves 565 and I15 cannot be opened until a suificient pressure is built up in the upper end of the cylinin the press of the present invention than is required in presses where the work is submerged in the quenching medium. 7

Another feature of the press shown is the use With such a die, all the pressure exerted on the upper end of the piston 56 is applied directly to the-gear throughout the whole of the quenching operation, Whereas in presses where the work is submerged, the pressure on the work is effected by the movement of the lower die until the work has been submerged. The use of a stationary lower die has the further advantage of enabling gearsto be held more rigidly so that they come from the press flatter on, the bottom and truer in the bore than with presses where the work is submerged. A further advantage of the'press with the stationary lower die is the fact that there are no moving parts under the quenching liquid. Hence even Water may be used as a quenching medium without danger of rust affecting the life of the press.

While the inventionhas been described in com nection with a particular, embodiment and with a particular use for this embodiment, it will be understood that the invention is capable of further modifications and uses and that this application is intended to cover any adaptations, uses, or embodiments of the invention following, in general, the principles of the invention and including such departures from the present disclosure as c-ome within known or customary prac tice in the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth and as fall within the scope of the invention or the limits of the appended claims.

Having thus described our invention, what we claim is: p

1 In a quenching press, a stationary work support, a source of supply for the quenching liquid, a valve normally preventing how of liquid from said source of supply to the work, pneumatically-operated means for clamping the workon said support, pneumatically-operated means for opening said valve, and means connecting the secondpneumatically-operated means to the first so that the second is operated by rise of pressure in the first when the work is clamped on said support.

2. In a quenching press, a support for the article to be quenched, a cylinder, a piston movable therein under pneumatic pressure, a die secured to said piston and adapted to clamp the article to be quenched on said support when said piston is moved in one direction in said cylinder, a source of supply of the quenching liquid, a normally closed pressure operated valve for controlling flow of liquid from said source of supply to the article to be quenched, said valve being connected to said piston so as to be opened when the pressure on said piston holding the die in clamping position reaches a predetermined amount and to be closed when the pressure on said piston falls below said predetermined amount, and means controlling the direction of application of fluid pressure to said piston.

3; In a quenching press, a stationary work support, a reservoir for the quenching liquid, ducts connecting said reservoir with the work support, a normally closed chamber adapted to contain a definite volume of a gas under pressure, means for clamping an article on the work support, means for supplying gas to said chamber, means operable to shut off said gas supply and means operable, after said gas supply has been shut off, to connect said chamber with said reservoir to force quenching liquid out of said reservoir through said ducts by gas-pressure.

l. In a quenching press, a stationary work support, a reservoir for the quenching liquid, ducts connecting said reservoir with the work support, a normally closed chamber adapted to contain a definite volume or" a gas under pressure, means for clamping an article on the work support, means for supplyin gas to said chamber, means operable to shut off said gas-supply, and means operable automatically after an article has been clamped on the work support and after said gas-supply has been shut off, to connect said chamber with said reservoir to force quenching liquid out or said reservoir through said ducts by gas-pressure.

5. In a quenching press, a support for the article to be quenched, a reservoir for the quenching liquid, a. chamber adapted to contain air under pressure and adapted to be connected with said reservoir toenable the air to force liquid from said reservoir around the article to be quenched, a source of air supply, a reciprocable member for clamping the rticle on said support, and a three-way valve controlled by the reciprocation'of said member to admit air from said chamber tosaid reservoir when said clampin'g member has been moved to clamping position and to reconnect said chamber with the source of air supply when said clamping member is moved to inoperative position.

6. In a quenching press, a support for the article to be quenched, a reservoir for the quenching liquid, a chamber adapted to contain a definite volume of gas under a definite pressure, a source of supply for the quenching liquid, pressure operated means for clamping an article on said support, pressure operated valve for controlling admission of gas from said chamber into said reservoir, and a pressure operated valve controlling flow of liquid from said source of supply to said reservoir, and means operatively connecting said valves to said clamping means so that said valves are operated by rise of pressure on the clamping means when an article is clamped on said support.

'7. In a quenching press, a stationary support for the article to be quenched, a clamping memher for securing said article on said support, a source of supply for the quenching liquid, a normally closed air-pressure operated valve controlling ilow of the quenching liquid from said source around said article, air pressure operated means comprising a cylinder and a piston reciprocable therein for moving the clamping member to and from operative position, and a duct connecting. said valve with the side of said piston which is on pressure when the clamping means is moved to clamping position, whereby, when the article is clamped on the support under a predetermined pressure, the back-pressure in said duct will open said valve.

8. In a quenching press, a stationary support for the article to be quenched, a clamping member for securing said article on said support, a reservoir containing a definite amount or quench-- ing liquid, a chamber adapted to contain a definite volume of air under pressure, a normally closed air-pressure operated valve controlling flow of air from said air chamber to said reservoir, ducts leading from said reservoir around the article to be quenched, means comprising a cylinder and a piston reciprocable therein for moving the clamping member to and from operative position, and a duct connecting said valve with the side of said piston which is on pressure, when the clamping member is moved to clamping position, whereby, when the article is clamped on the support under a predetermined pressure, the back-pressure in said duct will open said valve.

9. In a quenching press, a chamber adapted to contain a deimite volume of. compressed air, a reservoir adapted to contain a definite volume of the quenching liquid, a stationary support for supporting the article to be quenched above the normal level of liquid in said reservoir, ducts connecting the reservoir with the support to conduct liquid from said reservoir to an article mounted on said support, a normally closed valve controlling the connection between said chamber and said reservoir, means for clamping an article on said support, and means automatically responsive, when the article is clamped at a predetermined pressure, to open said valve to permit iiow oi the compressed air from said chamber into said reservoir to force the liquid out of said reservoir through said ducts and around said article,

10. In a quenching press, a chamber adapted to contain a definite volume of compressed air, a reservoir adapted to contain a definite volume of quenching liquid, a stationary support for supporting the article to be quenched above the normal levelof liquid in said reservoir, ducts connecting the reservoir with said support to conduct liquid from said reservoir around an article mounted on said support, means for clamping an article on said support, and a normally closed valve operable by said clamping means for controlling flow of air from said chamber to said reservoir.

11. In a quenching press, a stationary worksupport, a reservoir adapted to contain quenching liquid, a chamber adapted to contain a definite volume of gas under a definite pressure, ducts for conducting liquid from said reservoir to the work, a valve controlling connection of said chamber with said reservoir, pneumatically-operated means for clamping the work on said support, pneumatically-operated means for op crating said valve, and means connecting the two pneumatically operated means together so that the second is operated by rise of pressure in the first when the work is clamped on said support.

12. In a quenching press, a stationary work support, a reservoir for the quenching liquid, ducts for conducting liquid from said reservoir to the work support, a chamber adapted to contain a definite volume of gas under pressure, a connection for supplying gas to said chamber, a movable member for clamping an article on the work support, means for closing the connection between said chamber and the source of gassupply when the clamping member is moved to clamping position, and means for connecting said chamber to the reservoir when the article is clamped on said support.

13. In a quenching press, a stationary work support, a reservoir for the quenching liquid, ducts for conducting liquid from said reservoir to the work support, a chamber adapted to contain a definite volume of gas under pressure, a connection for supplying gas to said chamber, a movable member for clamping an article on the work-support, means for automatically closing the connection between said chamber and the source or" gas-supply when the clamping member is moved to clamping position, and means for automatically connecting said chamber to said reservoir when the article is clamped on said support under a predetermined pressure.

14. In a quenching press, a stationary worksupport, a reservoir adapted to contain quenching liquid, ducts for conducting liquid from said reservoir to the work support, a connection for supplying liquid from a source of liquid-supply to said reservoir, means normally closing said connection, a chamber adapted to contain a definite volume of gas under pressure, a connection for supplying gas to said chamber, a movable member for clamping an article on the work support, means for automatically closing the connection between said chamber and the source of gas-supply, when the clamping member is moved to clamping position, means for automatically connecting said chamber to said reservoir when the article is clamped on said support under a predetermined pressure, and means for simultaneously opening the connection between said reservoir and the source of liquid-supply.

15. In a quenching press, a stationary work support, a reservoir adapted to contain quenching liquid, ducts for conducting liquid from said reservoir to the work support, a chamber adapted to contain a definite volume of gas under pressure, a connection for supplying gas to said chamber from a source of gas supply, a movable member for clamping an article on the work support, a valve for controlling the connection of the chamber with the source of gas supply and operatively connected to said movable clamping member to be open when said clamping member is in released position and closed when the clamping member is moved to clamping position, and means operatively connected to said movable member for connecting said chamber to said reservoir when the article is clamped on the work support under a predetermined pressure.

16. In a quenching press, a stationary Work support, a reservoir adapted to contain quenching liquid, a connection for supplying liquid from a source of liquid'supply to said reservoir, a valve normally closing said connection, ducts for conducting liquid from said reservoir to the work support, a chamber adapted to contain a definite volume of gas under pressure, a connection for supplying gas to said chamber mm a source of gas-supply, a movable member for clamping anarticle on the work support, a valve for controlling the connection of the chamber with its source of gas-supply and operatively connected to said movable clamping member to be open when said clamping member is in released position and 'closed when the clamping member is moved to work support secured to the frame, a cylinder and a piston one of which is fixed relative to the frame and the other of which is movable, means secured to the movable part for clamping an article on the work support, a reservoir adapted to contain quenching liquid, ducts for conducting liquid from said reservoir to the work support, a chamber adapted to contain a definite volume of gas under pressure, a normally closed pressureoperated valve controlling flow of gas from said chamber into said reservoir, a duct connecting said valve with the side of the piston which is on pressure when the clamping member is moving to clamping position whereby when an article is clamped on the work support under a predetermined pressure, the back-pressure in said duct will open said valve, a second valve controlling connection of the chamber with the source of gas-supply, and means operatively connecting said second valve with the movable clamping member to close said valve on movement of the clamping member to clamping position and open said valve when the clamping member is withdrawn from clamping position.

18. In a quenching press, a frame, a stationary work support secured to the frame, a cylinder and a piston one of which is fixed relative to the frame and the other of which is movable, means secured to the movable part for clamping an article on the work support, a reservoir adapted to contain quenching liquid, ducts for conducting liquid from said reservoirto the work support, a chamber adapted to contain a definite volume of gas under pressure, a connection between said reservoir and a source of liquidsupply, a connection between said chamber and the reservoir, a pair of pressure-operated valves controlling, respectively, the connection between the reservoir and its source of liquid-supply and the connection between the chamber and the reservoir, means operatively connecting said valves with the side of the piston which is on pressure when the clamping member is moving to clamping position whereby when an article is clamped on the work support under predetermined pressure the back-pressure will open said valve, a third valve controlling connection of the chamber with a source of gas-supply, and means operatively connecting said third valve with the movable clamping member to close said valve on movement of the clamping member to clamping position and open said valve when the clamping member is withdrawn from clamping position.

LEON D. SLADE.

WARNER T. COWELL.