US 312959 A
Description (OCR text may contain errors)
1v1. P. W. BOULTON xv E. PERRETT. SUPERHEATED STEAM ENGINE.
No. 312,959. Patented Feb. 24,1885.-
UNITED STATES PATENT OEETCE,
MATTHEV PIERS WATT BOULTON, OF TEW PARK, COUNTY OF OXFORD, AND EDWARD PERRETT, OF WESTMINSTEE, COUNTY OF MIDDLESEX,
SPECIFICATION farming part of Letters Patent No. 312,959, dated February 24, 1885.
Application filed June 152, 1884. (No model.) Patented inEngland December 18, 1883, No. 5,797; in France June 12, 1884, No. 162,704,- in Germany June 15, 1884, No. 30,080; in Belgium June 19,1834, No. 65,533, and in Italy June 30, 1884, XXXIII, 400.
To @ZZ whom t may concern:
Be it known that we, MATTHEW Pri-insW in Great Britain, No. 5,797, dated December 18, 1883,) of which the following is a specification.
Our invention relates to a steam-engine worked by steam which, previous to performance of work in the engine, is highly superheated.
IVe will describe one form and arrangement of engine according to our invention, referring to the accompanying drawings.
Figure 1 is a vertical section, partly in elevation, and Fig. 2 is a plan, partly in section.
The engine consists of the following principal parts: a steam boiler or generator, G, a heater in duplicate A and A2, two singleacting hot cylinders-a smaller, B', and a larger, BL-and an ordinary double-acting steam-cylinder, C. The pistons of the two cylinders B and B2 are connected to one crank, and the piston of C is connected to a crank at about right angles to the former, both cranks being on a shaft, F, on which there are suitable cams or eccentrics for working the valves of the cylinders.
The boiler G may be of any known construction capable of generating hi gh-pressure steam, and provided with the usual feed, gage, and valve fittings. From its steamspace a pipe, g, provided with a shut off valve, leads to three branches, g gZ g3, each having a shutoff valve, g', leading to the heater A, g2 leading to A2, and g3 to the pipe supplying the cylinder B. Each of the heaters A A'L is of the same construction as that describedV and claimed in the specification accompanying our application,now pending,for Letters Patent for caloric orhot-air engine, No. 134,703, and is therefore not herein claimed. The heater A is an upright cylindrical vessel having in its lower part a fireplace, a, the access to which can be tightly closed by a cover, a. Above the tire-place there are superposed a number of circular slabs, a2, of fire-brick or equivalent refractory material,perforated by numerous holes, and having spaces between them for free passage of air, steam, or other gaseous iuid.
Instead of using perforated slabs, ordinary fire-bricks may be built up with interstices between them.
Above the refractory material there is-a brick dome, c, from the periphery of which a metal plate partition, ci, extends down nearly to the bottom of the vessel, dividing into two annular channels the space surrounding the refractory structure. From the top of the vessel there is a passage to a chimney, E, provided with a valve, a5, by which. it can be tightly closed. Two pipes, g and a?, each provided with a shut-off valve, communicate with the interior of the vessel-the one at the top and the other in the lower part. The other heater, A2, is in every respect similar to A', and the two are worked alternately in the following manner: The valves of g and al of A being closed, and the door c and chimney-valve c5 being open, a iire is kept fior several hours burning in the fire-place c. The fiames and hot products of combustion pass up through the holes or interstices of the firebricks ai, are deflected by the dome c down the annular channel within the partition c4, then ascend outside c4, and pass away by the chimney E. Vhen the fire-bricks ai are thus heated, the door c and chimney-valve 'a5 are tightly closed, the valves of g and a7 are opened, steam from the boiler G enters by g', passes down the annular channel outside of ai, ascends inside c4, is deflected by the dome a, passes through the interstices of the hot fire-bricks a, becomes superheated,and issues by the pipe ci. Vhile A is being heated by re within it, A2, which had been previously heated, is employed for heating the steam,
and when A is sufficiently heated and A2 cooled their operation is inverted-that is to say, AIl is now heated by fire within it,and A is employed to heat the steam. The annular channels on each side ofat, by maintaining a l lower part of the cylinder D, and this steam jacket of steam not superheated Vbetween the outer casing and the hot bricks within, reduces loss of heat by conduction and radiation.
The cylinder B is made in two parts. The upper part, which receives the hot steam, consists of two metal cylinders separated bya fectly-conducting material, such as asbestus sheet, to lessen as much as possible conduction of heat from the one .part of the cylinder to the other. The lower part of the cylinder is tted with a packed piston, b3, having projecting up from it a shield, b, deep enough to occupy all the hot part of the cylinder when the piston is up.
To the under side of the piston b3 is attached a block, b5, of wood or other equivalent bad conductor of heat, which occupies the lower part of the cylinder when the piston is up. There are two valves, DE and bl, worked by cams or eccentrics on the shaft F, to govern passages to and from the upper end of the cylinder B. The passage of bf communicates bya pipe, 06, with the branches a7 from the two heaters A A2, each of which branches, as already mentioned, can be closed by a shutoff valve. Thepassage of bl communicates by a pipe, bw, with the lower part of the cylinder B2. lThis cylinder is similar to B', but inverted, and it preferably has under it, at b, a small fire-place, or it might be gas-burners, to keep the bottom hot. From the lower part of B2 there is a passagel governed by a valve, c, which is worked by an eccentric or cam on the shaft F. This passage leads toa reservoir, c2, forming a casing, which surrounds the cylinder C, and communicates with the jacket of itsslide c. The reservoir c2 may be kept hot by passing the hot products of combustion by the pipe i5 from. the fire or burners b through a space, c, below the reservoir, these products escaping by a pipe, c6. In the drawings this lreservoir is shown encompassing the cylinder C; but it may be a separate vessel placed in any convenient position.
The piston and piston-rod of the cylinder G may be of ordinary construction. In the drawings,` however, we have shown an arrangement for -keeping the piston hot. For this purposethe piston is hollow and the pistonrod-is tubular with a smaller tube inside of it. The tubular piston-rod has attached to it besides its cross-head d a smallerhollow piston,
d, working in a cylinder, D, which also servesnds its way, by lateral holes a: in the tubular piston-rod,down the annular space therein, to the interior of the piston of C. The water of condensation passes up the internal tube of the piston-rod into and above the small piston d and is discharged at d3.
From the slide facing of the cylinder C there is a passage, cl, for the exhaust-steam, which may be either blown off or condensed.
The above-described plan of warming the piston is more particularly useful if a further or fourth cylinder is added, in which the eX- pansion of steam is continued. 'It will be understood that such a cylinder may be added to the construction shown in the drawings. As it would not differ from cylinders ordinarily used, it has not been thought necessary t0 show it. l rlhe operation of the engine is as follows: Steam generated at high pressure in G passes through one or other ofthe heaters AAi, becoming superheated. It acts first in the cylinder B, and then, expanding, acts in the larger cylinder B2. Reduced in temperature by expanding and performing work, it iiows into the reservoir ci, and this supplies thecylinder C as an ordinary steam-cylinder is supplied. The heat of the steam supplying the cylinder B can be tempered by admitting with it more or less steam not superheated, but led direct from the generator Gr by the pipe g3. i
Although we have shown in the drawings and described a particular form of engine and a particular arrangement of its main parts, it is obvious that these parts could be variously proportioned, constructed, and arranged to operate in the manner described. Although we have described two heaters, A A2, arranged to act alternately so as to provide for continuous action of the engine, it is obvious that when the action is intermittent a single heater maybe used. For instance, for an engine working only during the day, one heater will suffice, this being heated during night hours, and being used for superheating during the day.
Having thus described the nature of our invention and the best means weknow of carrying it out in practice, 'we claim- 1. In engines workedl by steam or vapor, the combination of a boiler or generator with a heater containing tire-brick or suitable refractory material disposed with numerous in,- terstices, the whole arranged and operating in such manner that the heater at one time is heated by tire under kordinary pressure, and afterward it is put in communication with the boiler and engine, so that the steam Orvapor on its way from the boiler to the engine passes through the interstices of the heater,
becoming thereby superheated, and enters the steam-boiler, G, a heater or heaters, A A2, a, two subscribingwitnesseshis l2thdayof May, pair of hot-steam cylinders, BB2, andan ordi i A. D. 1884. nary steam cylinder, C, with theil1 pipes, 1 valves, and eonnecbions,ar1anged and operat- 1 5 ing substantially as described. iVitnesses:
In testimony whereof We have signed our OUVER IMRAY,
l JNO. P. M. MILLARD.
M. P. W. BOULTON. FDVARD PERRETT.
names to this specification, in the presence of