US20514A - Steam-power meter - Google Patents

Description

2 8h tv GI SCHUH' ees Sheet 1 Dynamometer.

No. 20,514. Patented June- 8-, 1858.

- 2 PEYERS. PhnmLichommr, Washington. RC

- 2 Sheets-Sheet 2'.

G. SCHUH. Dynambmeter.

Patented June 8, 1858.

UNITED STATES PATENT OFFICE.

GEORGE SGHUH, OF MADISON, INDIANA.

STEAM-POWER METER.

Specification of Letters Patent No. 20,514, dated June 8, 1858.

To all whom it may concern:

Be it known that I, GEORGE SoHUH, of the city of Madison, in the county of J eiferson, in the State of Indiana, have invented a new and useful improvement on the steam-power meter for ascertaining and registering the exact amount of work done by any steam-engine during any period of time; and I do hereby declare that the following is a full and exact description.

My improvement has reference to a meter which has before been applied to a steam engine for ascertaining and registering the amount of work done by the engine during any period of time, the principle of action of which has consisted in the production of two motions, one of which was equal to the motion of the engine piston, or proportional thereto, and the other equal or proportional to the pressure of the steam on each square inch of the pistons surface, and, by combining these two motions, a third motion was produced which under all possible variations of the two former, was always equal to the first multiplied by the second and represented and indicated by means of a counter the amount of work done for each square inch of the pistons surface, which multiplied by the whole area thereof gave the total amount of work done by the engine in a given period of time. This was the theory of the device on which my invention is an improvement, for the practical or efficient performance of which much depends upon details for the carrying of the theory out. Thus, while I employ as in the previous device just referred to, a revolving disk set in motion through pulley and rope by the cross-head (say) of the engine, and a friction roller bearing on the face of the disk and driven by it, said roller being held to said disk by spring pressure and acted on by a further spring to occupy a central position on the disk but free to move across the disk and being urged across the disk first to the one side and then to the other of the disks center, each reciprocating action of the engine, by an independent motion derived from the pressure of the steam on a separate piston surface having communication, to reverse its action, with either end of the engine cylinder alternately, and according to the radial distance said roller is made to occupy, by such independent pressure, on the face of the disk, coupled with the velocity of the disk as a driver, is a quicker or slower revolving motion given to the roller which by suitable gear is connected with the counter, and the indication specified produced. Yet, my arrangement of means for producing a like result importantly differs. Thus, I make one independent steam cylinder and one piston, for urging the friction roller across the disk, answer for two; and employ a tongs form of spring and swinging quadrant action as the resisting means to the steam pressure of the roller across the face of the disk, which is a more accurate, durable, and room-saving arrangement and admits of the spring which keeps the roller bearing on the face of the disk traveling, from a fixed center of suspension, along with the roller, so as always to bear with equal force directly on the roller; and, instead of driving the disk by the rope in only one direction of the engines travel and depending for the revolving motion of the disk in the reverse direction by a spring attached to the disk and wound by it in its previous travel, I employ a different arrangement, of two ropes or cords connected with the cross head of the engine, for giving motion to the disk in exact correspondence with the travel of the engine piston in both directions, and provide said cords with compensating springs, to meet variations of atmosphere or other influencing causes affecting the stretch of the ropes, to obviate loss of motion in the driving disk, which, in this instance, would affect the count.

To enable others skilled in the art, to make and use my invention, I will proceed to describe its construction and operation.

Figure 1, in the annexed drawing is a front view of the instrument. Fig. 2, is a side View of the same. Fig. 3 is a section by a horizontal plan passing through the axis of the cylinder A. Fig. 4 is a perspective view of the instrument representing the same connected with a horizontal steam engine.

In all the figures the same pieces are marked with the same letters.

A is a small cylinder in which is working a piston a steam tight but easy. This piston when not under any steam pressure stands in the middle of the cylinder A and its rod 7) passes out at equal distances on each side through the piston heads o, and is packed hole or eye in its center, through which passes freely a square shaft cl which has a round journal on one end revolving in a stand, and the other end is square, and engaged in the square center hole of an endless screw D. V V

The cylinder A is secured to the bed plate K by means of two collar bolts a which are bored through in their center; 00 and y are two small steam pipes of which one is connected to each of the collar-bolts 0c and the other ends respectively to the two ends of a cylinder of a steam engine, so as to bring each end of the steam cylinder in communication with its respective end of the cylinder A and by that means the actual working pressure on any side of the piston of the steam-engine will be communicated to the respective side of the piston in the cylinder A, and the pressure on equal surfaces on both pistons are always equal.

H is a pendulum arm which swings around the stud L and its end is connected by means of a pin or a'friction roller with the carriage B and embraces by means of the heels [2, a spring at which is entirely distended when the piston (a is in the middle of the cylinder. The spring m bears on each side against the studs Z, and M is another piece which keeps the spring m in its place. A spring 2' is secured to the pendulum arm and swings with the same and presses on the carriage B above the center of the friction wheel 0 which is pressed constantly against a face plate E. The surface of the faceplate E is roughened in lines running toward its center, and is secured to a shaft 6 bearing a pulley f of which the diameter is such that one circumference of the driving cords T is exactly one foot in length. Those cords T are connected to the T head N of the engine piston by running over leading pulleys, 0 and for each foot motion of the piston the friction disk or face plate E will make one revolution turning alternately from left to right and from right to left by the inward and outward strokes of the piston; into those cords T are inserted springs Q which are destined to keep the cords T stretched and prevent any lost motion in the pulley.

O is a column secured to the engine bed near the cylinder and receives the instrument, and P represents the T-head slide, and G is the first wheel of the counter having 100 teeth, and in gear with the screw-worm D. The axle of this first wheel bears a hand turning over a face plate divided into 20 parts, each division indicates 100 pounds elevated one foot high byeach square inch of the surface of the piston and 1 revolution of the hand on the face plate indicates 1 ton elevated 1 foot high by the same sur face, as will be shown hereafter, the second Wheel on the counter makes one revolution for each 10 revolutions of the first and its face plate being divided in 10 parts will show the tens of tons elevated one foot high by one square inch &c. There are 2 grease kegs a which serve to introduce grease into the cylinder A. y

m is a steel spring the ends of which are applied exactly, in its uncompressed state, between the studs Z and also between the heels 7b of the pendulum H. Consequently when the piston is carried to either side by the steam pressure, it will move the carriage B and the pendulum arm H to the same side, the heels 71, will compress the spring m on the right or left side until it is in the equilibrium with the pressure on the piston a, and the pressure on each square inch, on either side of this piston is shown by a graduated scale 8. Then there is equality of pressure or no pressure on either side of the piston a. this latter is held in the middle of the cylinder A and the friction wheel 0 in the center of the friction-disk E, and if even the disk E be in motion, the frictionwheel 0 would stand perfectly still. (This would be the case in a river-steamer when the steam is shut off from the engines and the paddle wheels are put in motion by the current of the water; as also in a locomotive when the steam is shut off and the train continues in motion by the power communicated to it previously, and which power is in that case already registered by the instrument.) By the expression pressure, in the above, I mean the difference or excess of pressure on the one side of the piston a over that of the other side, for it is evident, should there be, by any defect in the engine, a pressure at the same time on both sides of the engine piston, the piston a of the instrument will be acted on in the same manner and show the excess of the higher over the lower pressure, which is the actual useful working pressure of the engine, also in the case of a condensing engine with a partial vacuum on one side of the piston andthe steam pressure on the opposite side, the difference of pressure on the two sides of the piston is the actual useful pressure and will be shown and brought in operation by the instrument.

I will now describe the general working of the instrument when attached to a steam engine. When the steam presses the front end of the engine piston it will move the same with its T-head N out on the slide P in the direction of the arrow, and by means of the cord T and pulley f turns the friction plate E one revolution for every foot of the stroke, but in the same moment the steam having also pressed on the piston a has moved the same with thecarriage B and everything attached to it, to the left and at a distance equal to the number of pounds pressure, say 1001b. The diameter of the friction-wheel 0 is of the diameter of the circle corresponding to 1001b on the plate E, and this wheel 0 will revolve 5 times for each revolution of the plate E and for each foot stroke of the engine piston. If the engine has 5 feet stroke the wheel 0 will make 25 revolutions for every stroke, and by admitting the pressure of the steam to be 100 lb in the cylinder during the whole stroke, the friction wheel 0, with the square shaft (Z and the endless screw D attached to it have made 25 revolutions, and the counter-wheel Gr having 100 teeth and its hand over the face of the counter have been turned revolution, and will show 5001 or 9; ton elevated 1 foot high by one square inch surface of the piston. If instead of working at full pressure all the length of the stroke, the steam had been cut off at any time during the stroke, or the pressure of the steam in the cylinder varied by any other cause, the friction wheel 0 would have occupied at every instant a position distant from the center of the disk E corresponding to such pressure, and the resulting motion of the counter, produced by the varied motion of the friction-wheel 0 would have been such as to show again the number of pounds elevated one foot high by each square inch of the engine piston. The piston being at the end of its stroke, and the steam escaped, then by the pressure of the spring m the friction-wheel 0 will be moved to the center of the disk E, in the next instance the steam presses the piston on the opposite side, and the piston a with everything attached to it, including the friction-wheel c, are moved to the opposite side, and all the motions during the first stroke are repeated, but the face plate E being moved in the opposite direction will move the wheel 0 (it being on the opposite side of the circle) again in the same direction as at the first stroke, and consequently the counter will add the amount of work done by the second stroke to that of the first. It will be seen that for each successive stroke or revolution of the engine the instrument will work in the manner described, keeping always an exact account of the amount of work done by the engine under all possible variation of speed and steam-pressure.

The power-counter shows the amount of work done by 1 square inch of the surface of the piston. The number of square inches of the piston surface will be multiplied by the quantity shown on the counter to obtain the total work done by the engine. By securing a paper disk to the face-plate E and a pencil in the place of the frictionwheel a the instrument can be used to describe an indicator diagram, the abscissas and ordinates of which would be the circumferences and radius of the circle.

There may be a second counter connected with the instrument, and put in motion by the pendulum arm H or any other, movable piece of the instrument. This counter will indicate the number of revolutions made by the engine.

This instrument is intended to be used in all engines, be the motive power steam, air, or any other gas.

The benefits and services that will be obtained by the use of this instrument are too obvious to be mentioned, when we take in consideration, that the real performance of an engine, or the amount of steam power required to propel a steamboat, even for one single mile, or that required to spin or weave a bale of cotton, have been and are without this or other previous instrument of the kind mere matter of approximative speculation or guess, but the instrument above described will tell with a certainty the amount of power required, to overcome friction or to produce a certain amount of work, &c.

WVhat I claim as my improvement, and desire to secure by Letters Patent, is:

1. The combination of the one independ ent piston (a), working in its cylinder (A) and actuated in opposite directions alternately by the steam from opposite ends of the engine cylinder acting successively on its opposite sides or faces, carriage (B), pendulum (H), main spring (m), secondary spring friction wheel or roller (0), and disk (E), arranged for operation together in the manner and for the purposes set forth.

2. I also claim driving the disk (E), in both directions of its travel, by cords (T) operated by the engine; whereby a velocity, corresponding to the velocity of the piston of the engine, is at all times and throughout both strokes, communicated in a positive and accurate manner to the friction wheel (0), for the purposes mentioned.

3. And I further claim providing the driving cords (T), with compensating springs (Q), when said cords and springs are combined for action with the reciprocating disk and reciprocating head block (or its equivalent) of the engine piston rod essentially as described, to prevent material pause of the disk at the end of each stroke, and irregularity in the action of the disk, by the driving pull on either cord alternately producing stretch and the relaxing of either cord when not acting as a driver; for the purpose of securing accuracy in registering as specified.

Madison, Indiana, this 15 day of February, 1858.

G. SGHUH.

Witnesses:

R. L. IGEL, L. ROSSITER.

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