US70369A - Improvement in the valve-gear of steam-hammers - Google Patents

Description

UNITED STATES PATENT OEEIoE.

n WILLIAM SELLERS ANDACOLEMAN SELLERS, OF PHILADELPHIA, PENNSYL- YANIA, ASSIGNORS T() VILLIAM SELLERS &; CO.`

IMPROVEMENT IN THE VALVE-GEAR OF STEAM-HAMIIVIERS.

Specification forming part of Letters Patent No. 70,369, dated October 29, 1867.

To all lwhom it may concern:

Be it known that we, WLLLIAM SELLEEs and COLEMAN SELLERS, of the city and county of Philadelphia, in the State of Pennsylvania, have invented new and important Improvements in Steam-Hammers.

' The object of Iour invention is, first, to construct the valvegear ot' steam-hammers in such a manner that thevalve may be operated entirely by hand or entirely by power, or partly by hand and partly by power, in any part of or the whole of any or every stroke, at the will of the operator 5 second, to dispense with the movable steam-ports for regulating the stroke of automatic steam-hammers, and to simplify the construction of the valve gear;

. third, in that class oi1 steam-hammers in which the whole weight of the hammer iscontained in the hammer-bar and piston-head, and which are guided in wholeor part by the cylinderi head, or cylinder-heads and cylinder, to v,obtain from the hammer-bar a reciprocating movement to work the valve without subjecting' any part of this movement to shocks or blows.

The nature of our invention, sol far as the irst object is concerned, consistsinoperating the valve from any reciprocating -part of the hammer through a properly-proportioned le- 4 ver, to, which lever, at one point, the valve is attached7 `to .another the reciprocating-power is conveyed, and a third point serves as the attachment to the hand-lever, each of these points being fulcra in turn, according to the work required of the hammer. Thus, when workin g automatically, the fulcrum is the h andleverattachment. When worked by hand,the fulcrum is changed to the point of attachment ot' the reciprocating-power; and when it is desirable to raisefthe hammer and hold it up,

one motion of the hand-lever opens the valve,

and as the hammer rises the hand-lever and fulcrum controlled byliand. This featureof the invention is applicable to all steam-hammers, provided a proper reciprocating motion is attainable from the piston.

The nature of that partof our invention fulfilling the second object consists in obtaining the reciprocating motion from that part of the hammer-bar contained at all times within the steam-space of the hammer-cylinder or its connections.

In order that the invention may be fully understood, we will now proceed to describe its construction and operation, referring to the accompanying drawings, making part of this specification, and in which similar letters on each separate view refer to similar or equivalent parts.

The invention, so far as the valve gear is concerned, as expressed in the first object of our invention, is, as we have already said, applicable to all steam-hammers but to fully explain its advantages in connection with the second object-viz., the method of obtaining the proper reciprocating motive power-we will describe it as attached to that kind of steam-hammer known as the "Morrison hammer,77 and patented by Robert Morrison, March 4, 1862.

In this machine the whole weight` of the hammer is in the hammer-bar A, (see Fig. 2,) which is made in one piece with the pistonhead B. The bar extends upward above the piston-head, as at A', and passes through the upper cylinder-head, C', the hammer-bar being only guided by the lower cylinder-head and stuffing-box, C, and the upper head, C'. The upper part of the hammer-bar, A', extending through the cylinder-head C', is `flattenedon one side. Thisflat,ttingacorresponding surface in the hole through which it passes in the head C', prevents the bar from turning.

v In automatic hammers of this kind as heretofore constructed, the proper reciprocating motion needed for the valve has been attained by attaching to the upper end, A', of the hammer-bar (see Fig. 4) a projecting forked arm, el. This arm has a pin iitted through its fork, upon which is carried a sliding block, c'. The lever being curved of a proper radius, as the hammer bar rises and falls the lever f' is moved back and forth by the projecting arm I, and at the lever end ot f' gives motion to the valve. l In this arrangemeutthe projecting arm d and block c move at the same speed as the hammer-bar, are subject to the same shocks as it is, and are always liable to fracture or derangement by the blow. Added to this source of trouble, the rapid motion ofthe hammer-bar and sudden stoppage at the end of its stroke impart a rapid motion to the upper end of the lever f', causing it to thrash back and forth tothe detriment of itself and attached machinery. To avoid these troubles, and to have no part of the machineryv subject to, this rapid motion and shock save the hammer-bar only, we make a diagonal groove, It, in the flat of the upper part, A', of the hammer-bar, and we inclose the wholeI top of the hammer-bar by a cover, D, attached to the top cylinder head, C. In this cover at E we provide an oblong opening, with which is fitted a cap, projecting in toward the hammerbar. Fig. 3 shows a section through m y of Fig. l', showing the cap, the cylinder, and hammer-bar. The hammer-bar iits the cylinder-head C for a distance about equal to the length of the cap E, above which there is steam-space allowed around the bar in the cover D. Steam from the cylinder iiows freely through the openings 7L h. rllhe cap E is provided with la rock-shaft, F, at the inner end of which is a rocker-arm, G, carrying on a pin a rectangular block, which is iitted loosely in the diagonal slot of the hammer-bar. The shaft-F passes through a stuffing-box, H, and has on its outer end a rocker-arm, I.

The operation of this part of the machinery is as follows: As the hammer-bar rises and falls the diagonal slot imparts, through the rocker-arm G and shaft F, a reciprocating motion to the external rocker-arm I. According to the angle made by the diagonal slot with the axis of the hammer-bar and the length of the arms G and I, a sufcient motion for worky ing the valve can be given to the end of the arm I. By reference to Fig. 3 it will be seen that projections 7c 7c on the cap E t straight grooves in the hammer-bar, to guard it against any lateral motion from the action of the diagonal slot in its required work. The diagonal slot is so placed in relation to the rockera-rms G and I that the end of arm I descends as the hammer-bar rises. A connecting-rod, M, unite the end of rocker-arm I to a lever, L, at the point M. At point K of same lever the slide-valve rod is attached, and at N a rod, N, connects lever L to the hand-lever O. The valve may be such as is ordinarily used on steam-engines, (see Figs. 5 and 6,) the port l leading to lower end of cylinder, the port 2 to upper end of cylinder, and the port 3 being the exhaust-passage. The valve-gear is so arranged that when hand-lever is at P', end of the quadrant P, and hammer-bar is down, both ports l and 2 will be covered by the slidevalve. When hand-lever is at I, end of quadrant I), and the hammer-bar is at top of stroke, the lower port will be a little way open, giving steam below the piston. The handlever O has a latch, to fix it at any point on the quadrant I?. 'v

With all the parts as shownv in Fig. l, hammer-bar down and hand-lever at P', the valve will be as at Fig. -i. e., both ports covered. It, now, steam be admitted to the steam-chest, none can enter the cylinder 5 but if the handlever bedrawn back toward P" a 'short distance, and held there, the valve will be raised more or less, according to the distance the hand-lever is moved, steam will pass into the cylinder and raise the hammer-bar. The block attached to lever G, and working in the diagonal groove of the hammer-bar, being loosely tted in the slot, will, as soon as the least motion has been taken up, be moved sidewise by the incline of the slot, pushing lever I down and depressing the lever L. The point of attachment to N being the fulcrum, it will continue to move the valve until the port is closed and the expanding steam below the piston, together with the velocity of the hammer-bar, has carried the valve over the port, giving steam on top of the piston and opening the lower exhaust. The last motion of the sliding block will allow the valve a short rest as the piston descends there, and will move the valve up to give steam below, thus alternately giving steam below and above, the rapidity depending upon the amount of steam admitted by throttle. If the handle be moved back but little, the stroke will be short; if moved back farther, the stroke will be longer and occur high up in the cylinder. Thus it can, when working automatically, be graded from the minimum to the maximum of the length of stroke of the hammer. As the hammerbar ascending opens the upper port, and descending it opens the lower port, it is evident that the velocity of the hammer-motion, governed by the admission of steam by the throttle, will influence to some extent the length of the blow, as it cushions on steam at both ends of its stroke. lf, now, the lever O be drawn back toward P, the hammer-bar will rise, as has been explained. If it be drawn all the way back to P, it will rise to the top of the stroke, and stay up as long as the steam-pressure is continued. This is because the valve has been thrown up farther than the descending motion of the rod M has power to restore.

If the handle be pushed toward P slowly, the bar will descend as slowly. If moved quickly, it will descend with the velocity due to the pressure of steam on top of piston, added to the weight of the bar, as it will have an almost clear exhaust below, so that moving the hand-lever back and forth at each stroke will give a perfect hand-motion to the bar, slower or faster, at the will of the operator. While the hammer is workin g on any given length of stroke automatically, as a necessity the force of the blow is somewhat modified by the steam which is admitted below the piston before it reaches the bottom of the stroke. If, however, the hand-lever be drawn back a little-say a tenth part of its whole range-and as the bar descends it is pushed forward as much, thus keeping time with the hammer-stroke, a blow of nearly the same intensity will be given as if worked solely by hand, thus combining the hand and power movements.

The merit of the invention is manifest when it is understood that in this arrangement of each motion, by means of the one single lever O, the operator is capable of working the hammer automatically and regulating its length of stroke to the greatest nicety, giving light or heavy strokes at will, or he can work it by hand, striking one blow or a succession of blows, and holding up the hammer while work is being adjusted, thus controlling the hammer as perfectly as if it were an ordinary hammer held in his hand, thus fulilling perfectly the objects of the invention.

It must be edent to every intelligent mechanic that all the parts composing the valvemotion may be modified in many ways without interfering with the theory of the invention, as the valve-motion can `be attached to any steam-hammer for which is obtainable a proper reciprocating motion equivalent to that of the rock-shaft I. The circumstances of each case to which it may be applied may involve some modification of the parts and their position. So, also, with the means of obtaining the reciprocatin g motion from the bar.

In hammers in which there is no projection above the piston-head, the diagonal slot, or any equivalent device capable of imparting a reciprocating movement to the valve-motion, may be made in the bar below the piston-head by forming a steam-space below the bottom cylinder and the bottom stufingbox as long as the stroke of the hammer, so that we do not limit our invention to the precise form and arrangement of parts as described; but

What we claim as new, and desire to secure by Letters Patent, is

1. The lever L, or its equivalent, when all its points of' attachment may be fulcra in turn, according to the work required of the hammer, substantially as described, and for the purpose specified.

2. The lever L, or its equivalent, when arranged in combination with the piston and slide-valve, so that the relative position of the piston and valve may be changed, for the purpose specified.

3. The diagonal slot, or its equivalent, in the hammer-bar within the steam-space of the cylinder or its connection, for the purpose specified.

WM. SELLERS. COLEMAN SELLERS. Witnesses:

UHAs. W. PEALE, THos. A. SMITH.

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