US2046447A - Steam hammer - Google Patents

Description

July 7, 1936. E. c. CLARKE 2,046,447

STEAM HAMME R Filed Jan. 30, 1934 4 Sheets-Sheet 1 Zggem Ci Carla? I July 7, 1936. E. c. CLARK 4 STEAM HAMMER Filed Jan. 30, 1934 4 Sheets-$heet 2 STEAM HAMMER Filed Jan. 50, 1934 4 Sheets-Sheet 5 E. C. CLARKE STEAM HAMMER July 7, 1936.

4 Sheets-Sheet 4 Filed Jan. 30, 1954 wx i WW 4% l 1 8 7 pg Patented July 7, 1936 UNITED STATES PATENT OFFIE STEAM HAMMER Application January '30, 1934,. SerialNo. 709,034

3 Claims.

This invention relates to improvements in steam hammers. An important object of the invention is the provision of 'a construction in a steam hammer which will. eliminate much of the wastage of motive fluid occurring in hammers as new constructed- In the steam hammers ordinarily constructed, due to the rapidity of action, it is desirable that reversal. of intake and exhaust functions shall take place as rapidly as possible. Such hammers' ordinarily incorporate ports at opposite ends of the cylinder for intake and exhaust, which ports are made of the same size, and accordingly will handle equal amounts of pressure: fluid and exhaust with the same facility. Quite obviously, a steam hammer, due to the weight of the head, the supporting rod, and the piston, has severe gravity eifects to' overcome, gwgravity assisting in the down-stroke; and resisting movement in the up-st'roke." An important factoris, of course, to provide as rapid as possible a down-stroke, and due to gravity effects, backpressure is set up unless the ports employed 3x801: relatively large size, and even then notice able back pressure effects occur. Since the larger the: port; the greater the time required for valve movement toopen and close the port; and this-has resulted in the: adoption'of medium size m ports providing, of course; an excess of pressure fluid inlet on the down-stroke, and an excess ofi back pressure. on such stroke, and aninadequate inlet om the lip-stroke.

An important object of thisinvention is the g zprov-isionrof a port arrangement such that the intake and exhaust. on'these strokes may be properly proportioned, therebyieli'm-inating back prasure: effects, materially economizing in pressure fluid.

401 Since such a port: arrangement necessarily radically differs: from-the ordinary port arrangement, and; incapable of. control by the usual type oi valve, arturther object of the invention is provision of a valve for controlling such- 45321303113 arran ement;

morerspeciflc object ofthe' "invention is the provisiomxof a slide valve so constructed that wean-is'reduced to a minimum, operation of the valve-facilitatezi, and. adjustment-oi the valve 50; to commensatefor wear in operation is readily effected.

A fiumther and more specific object oi the-in- 55i1i0f. the: valve: and consequent excessive wear in operation, together with difliculties inoperation, due tounbalanced pressures upon the valve, are completely eliminated.

A further object of the invention is the provision of a slide valve especially adapted for 5 use in conjunction with steam hammers and other constructions wherein it is desirable that the valve be so constructed and mounted that it I can move in at least one direction with practically no resistance. 10

A still further object of the invention is the provision of a valve so constructed that adjustments may be compensated for and the valve in spected to determine the necessity for adjustments of its condition while it is under actual 15- pressure.

Fig, 2 is a section on the line 2-2 of Fig. l; 25 Fig. 3 is a section on the line 3 -3 of Fig. I; Fig. 4 is a face view of the valve element;

Fig. 5 is a section on the line 5-5 of Fig. 4;

Fig. 6 is a section on the line 66 of Fig.4;

Fig. '7 is a section on the line 1 1 of Fig. 4; 303i;

Fig. 8 is a section on the line 8-8 of Fig. 4;

Fig. 9- is a view of one face of the adjustable plate;

Fig. 10 is a side elevation of the plate;

Fig. 11 is a view of the opposite side of the -6 plate; and N Fig. 12 is an enlarged sectional view through the adjusting means.

Referring now more particularly to the drawings, the numeral I0 generally designates a 40 valve chamber at present shown as a portion of the casting H of a steam hammer cylinder. The cylinder casting has formed therein upper and lower ducts l2 and It for the passage of fluid pressure delivered to the cylinder and exhaustedtherefrom. The lower passage l3 isv relatively large as compared to the passage I2, and at its throat l3 or point of communication with the cylinder is flared so that it may be branched about opposite sides of the cylinder to retain its relative large area. The duct l2 communicateswith the valve chamber l9 through relatively restricted port l5; while the duct i3 is branched and communicates" with the valve; hamber through ports I S- and ll of thesame this connection having about its periphery a seat admittedto the 'cylinderQjust suflicient to give the hammer the needed impulse and velocity, u and that during such down-stroke the relatively wide exhaust passage I3 provided will eliminate Conversely, on the any back pressure effects. up-stroke the passage I3 aflords means for admission 'of a relatively large amount of fluid during a short period, thus giving the initial speed'necessary on the up-stroke; while the restricted port I2 provides the necessary cushioning to prevent overunning 'of the piston? and consequentdamage to the cylinder. 1

'As illustrated, the plate I4' forms one working face of the valve chamber, and the ODDQSite working surface thereof is formed by' an adjust- V :zable pressure plate designated at I8.

This pres-. sure plate has a centrally located port I9 communicating through any suitable throttle valve .20 with a source of motive ,fluid pressure. The plate I8 has a male joint connection at 2I with a port 22 leading from the throttle valve 20,

for packing 23, providing the seal between the plate and the entry port for-motive fluid. It

will be noted that pressure of the motive :fiuid V will be exerted against the pressure plate to urge the same'toward the wear plate I4 through an area equal to the'diameter of the'joint connection at the periphery of the packing seat,"minus I g corresponding in siz n location i p r the'area of the port'le at the point of com-, munication with 1 the plates between wear and pressure plates I4 and I8. Comparison of these areas may be readilyihad by an inspection of Fig. 9 in which the periphery ofythe pressure areaat the outer face of ,thefplate appears at 24 {and the'mouth of the port IIIis indicated in dotted lines. y s

7 Between pressure plate I8 and the wall'of the 'chamber ID are arranged adjusting means generally designated at 25 and engaging the outer face of the plate at points adjacent the upper and-lower ends thereof. These adjusting means, as shown in Fig. 12, each comprise a trough:

shaped element 26 adapted to engage one ofthe. I opposed surfaces; a 'bar 2'Iadapted'to oppose the ,other of the surfaces, and shims 28 of desired thickness interposed between the element 26,;and

bar 21 within the trough These elements de-" termine the possible recession of plate I8 from plate I4. 'A further-adjusting means 29 similar' to the adjusting means 25 'is employed to vertically locate. plate I8 in the chamber. The plate I4 has formed therein a false port I9a' corresponding in size and location to the opening of port ISthrough the inner, face of plate .I8. Plate I8 hasfalse ports I5a, Him and I Ia I5, I6 andITof plate I4.

Between the plates I4 and l3, the valve 3I1is disposed, this valve'comprising a fiat-faced body :adapted to slidably ifit against the faces of the plates I4 and I8 and having formed therein intake and exhaust chambers 3| and-32. In the present type of valve construction, the intake chamber is divided into twosections which are {connected by a vertically extending ,duct 33 7 the valve body through openings of equal area.

,of the valve through a port 34, through the'sides formed in the valve body, see Fig, 6. Each of these chambers opens through opposite walls. of

The exhaust chamber 32 opens through one face of the valve, and has communication with a false port 35 of equal area with the port 34 and at the opposite, face of the valvefrom the port 34, through aduct'36; The valve body has ad'- ditionally formed therethrough ducts 31, 38 and 39, the purpose of which is to establish communication between each port I5, I6 and I1 and its corresponding false port I5a, Ifia or I'Ia.

The port I9 is maintained in continual commu- I nication with its false port. through the upper section of the-intake chamber. 7 V 7 With a valve of the type illustrated positioned as shownin Fig.1, when the valve is elevated; port I5 is placed in communication with port I9, and steam is admitted to the upper end of the cylinders; at thesame time the chamber 32 is thrown in communication with port I6; and

port I1 has access to the ,spacevaround the valve frombeneath the valve. When the' valve is low-1;- cred-chamber 3| isthrown into communication. 2 with port I6 throughits upper. section, and :the.

port I1 through its lower section; while pIorts I5 '1 r r is in communication with the} space .about'the 7 valvefrom abovethe'valve. p It. will be noted thatsince pressure areas on3 opposite faces of thevalves are equal, andsinceb areas throughcwhich pressure may bdexerted plates I4 and ;,I8'have corresponding pressure? against the valve, the-only pressure to whichvalve 30 will 'be subjected operation will' be 3 z the pressure resulting from adjustment of the plate I8, plate I4 being stationarily. secured I,

against the wallof the valve chamber. It will also be noted that the'space about the valve designated -at 40 is subjected only to. exhaust aroundthe valve, there is no resistance of exhaust pressure to 'movement of the valve in either direction. Likewise,fsince onlyL exhaustpressure exists about the valve,;-there.is' no necessity for heavily reinforcedtcover plates,:.and a light cover plate? may be employedlwhichfl when removed, will afford access to thevalve of motive ,fluid, so thatthe valve maybe'i'n spected in actualoperation. 1 1

In order that the pressure exertedzthrough' plate I8 may be readily regulated'and controlled:

the valve to such an: extentthat therewill be Y actual'bindingv in the absence of fluidpressui'e, I

and the valve will be freed immediately iupon o the admission of j-pressure fluid to such anextent that it will drop by gravity. Av valve' 'construc tion of this character, with proper adjustment of the means 25'will at all timesoperate' by gravity 1 on the down-,-stroke,-thusz making theiconstruc- 7 tion especially adaptable to use inpfluid-press'ure i I operated hammer constructions .by insuring-"a quick returnof the hammer to its raised' position following a working stroke.

It has been found that utilizing the construc 75;

t 40 .15 pressures, andsince this space-extends entirely 1 without the necessity of-;cutting off the supply V to the setting afforded by the shims 528, the V .tion set forth above results in material advantages in operation of the hammer. Ordinarily, in fluid pressure hammers of the type under discussion, it is necessary to give the dies employed in drop forging a draft of about 7; that is to say, these dies must be given a 7 taper in order that the die and work may be readily separated. Due to the high speed withdrawal of the hammer with the present construction, and to the high speed of the working stroke it has been possible to reduce this draft from 7 as low as 3 with a resultant material saving both in metal losses and in costs in the reduction of the finished stamping to its ultimate form. In addition to this, it is found that it is possible to use a much smaller cylinder with a consequent saving in fluid pressure, this saving being as high as 30 per cent. Furthermore, it is found that the falling weight of the hammer, that is to say the gravity weight of the hammer, can be materially reduced, the reduction in some instances being approximately 20 percent.

Obviously, certain features of the valve may likewise be employed with equal facility in a number of other forms, as for example, in the slide valve mechanism of a locomotive. Since the valve must necessarily be changed as to its operating structure for adaptation to various 'types of cylinders, I do not wish to be understood as limiting myself to the particular arrangement herein illustrated except as hereinafter claimed.

I claim:

1. In a fluid pressure hammer, a hammer cylinder, a hammer piston operating therein, a hammer rod. connected with the piston and extending through one end of the cylinder, a valve chamber, a relatively small port in one wall of said chamber constituting the sole means of communication with the opposite end of the hammer cylinder, a plurality of ports in said chamber Wall communicating with the firstnamed end of the hammer cylinder to simultaneously supply fluid to or exhaust fluid from said end of the hammer cylinder, the last-named ports being distributed longitudinally of the chamber wall, and valve means in said chamber for controlling said ports.

2. In a fluid pressure hammer, a hammer cylinder, a hammer piston operating therein, a

hammer rod connected with the piston and extending through one end of the cylinder, a valve chamber, a relatively small port in one wall of said chamber constituting the sole means of communication with the opposite end of the 10 hammer cylinder, a plurality of ports in said chamber wall communicating with the firstnamed end of the hammer cylinder to simultaneously supply fluid to or exhaust fluid from said end of the hammer cylinder, the last-named ports being distributed longitudinally of the chamber wall, a valve in said chamber for controlling said ports, said valve permanently covering one of said plurality of ports, and passages in said valve for alternately placing the lastmentioned port in communication with a source of fluid pressure and an exhaust.

3. In a fluid pressure hammer, a hammer cylinder, a hammer piston operating therein, a hammer rod connected to the piston" and ex- 5 tending through one end of the hammer cylinder, a valve chamber, a port in said chamber constituting the sole means of communication with the opposite end of the hammer cylinder, a

valve movable in the chamber controlling said port for the admission of fluid pressure to and exhaust of fluid pressure from the cylinder, port means in said chamber and communicating with the first-named end of the hammer cylinder, 'said port means having an effective length in the direction of movement of the valve greater than the corresponding length of the first-named port, said valve being so constructed and arranged that a movement thereof substantially equal to the width of the first-named port ren- 40 ders the entire area of the last-named port means available for supply of fluid pressure to or exhaust of fluid pressure from the first-named end of the cylinder. 7

EUGENE C. CLARKE.

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