US846005A - Compensating direct-acting engine. - Google Patents

Description

PATENTED MAR. 5, 1907.

W. 0. BROWN.

GOMPENSATING DIRECT ACTING ENGINE.

APPLICATION FILED SEPT. 7, 1904.

THE NORRIS PETERS co.. WASHINGTON, n. c

UNITED STATES PATENT OFFICE.

WILLIAM C. BROWN, OF PRESCOTT, ONTARIO, CANADA, ASSIGNOR TO HENRY R. WORTHINGTON, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

Specification of Letters Patent.

Patented March 5, 1907.

Application filed September '7, 1904. Serial No. 223.576.

To all whom it may concern:

Be it known that I, WILLIAM C. BROWN, a citizen of the United States, residing at Prescott, Province of Ontario, Dominion of Canada, have invented certain new and useful Improvements in Compensating Direct- Acting Engines, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

This invention relates generally to that class of direct-acting engines which are provided with one or more compensating or auxiliary cylinders and pistons which are supplied with a suitable motor fluid and are arranged to act in opposition to the main piston or pistons during the first part of the stroke of the engine and in conjunction therewith during the last part of the stroke, there by permitting the admission of the steam to the main cylinder or cylinders to be'cut off before the stroke is completed while main taining the proper power of the engine. Such compensating direct-acting engines are well known and different forms are shown and described in various United States Letters Patent. In such compensating directacting engines the pump is liable to make too long or too short a stroke under the varying conditions of use and the object of the present invention is to provide suitable means for automatically regulating or adjusting the compensating pressure so as to maintain a practically constant stroke of the engine.

The invention may be applied to compensating engines employing an accumulator between the compensating cylinders and source of compensating pressure or to engines in which no such accumulator is employed; but certain specific features of the invention relate to constructions employing such accumulators, and the invention will be illustrated and described in connection with such a construction.

-For a full understanding of the invention a detailed description of a construction embodying the same in its preferred form will 7 now be given, reference being had to the accompanying drawings, forming a part of this specification, in which- Figure 1 is a diagrammatic side elevation of a vertical pumping-engine embodying all the features of the invention in their preferred form. Fig. 2 is a detail outside view of the tappet and regulating-valve, with the latter opened by the tappet. Fig. 3 is a vertical section of the parts shown in Fig. 2.

Referring to said drawings, A is the steamcylinder; B, the pump-cylinder; C, the forcemain; D, the air-chamber on the force-main; E, the engine cross-head; F, the compensating cylinders having their pistons connected to the cross-head, and G the accumulator connected on one side of its piston H to the air-chamber D by pipe I and transmitting pressure to the compensating cylinders F from its smaller piston K through pipe L.

The accumulator is shown as of a Wellknown construction substantially the same as shown in United States Letters Patent Nos. 455,935 and 628,511 except for the persent invention, the effective pressure of the piston H being adjusted by admitting compressed air from an air-tank through pipe 10 to the under side of the piston H and this pipe 10 being connected by pipe 11, controlled by cook 12 with the air-chamber at the upper end of the cylinder G for the supply of air to the air-tank as desired. The usual gage and blow-off pipe 13 and safetyvalve 14 are shown. All the construction thus far described is old and may be of any other common or suitable form.

Referring now to the features added for the embodiment of the present invention, the cross-head E carries a tappet 15, which is preferably made adjustable, as shown, by screw 16 and set-nuts 17, and this tappet engages the upper end or the head of valve-rod 18, carrying valve 19, which is seated upon seat 1 in valve-chamber 20 by spring 21 when not engaged by the tappet 15. The valve-chamber 20 has below the valve-seat 1 an inlet-pipe 22, connecting with pipe I, so as to admit air from the air-chamber D to the valve-chamber 20, and above the valve-seat 1 a pipe 23, connecting with pipe 1 1, and thus through pipe 10 with the space below the accumulatorpiston H. When the valve 19 is forced off the seat 1 against the pressure of spring 21 by tappet 15 engaging the head of valve-rod 18, therefore air from the airchamber D passes through pipe 22, the valvechamber, and pipe 23 to the lower side of piston H, and thus increases the pressure on the lower side of the piston H and decreases the effective pressure tending to force the piston I-I dowward, so as to lessen the presl v I sure in the lower chamber of the accumulator in which piston K moves, and consequently the accumulator-pressure The amount of air that thus passes from the air-chamber l) to the accumulator-cylinder below piston H when the valve is opened by the tappet depends upon the length of time the valve 19 is open, which obviously depends upon the distance the valve is moved by the tappet or upon the length of the engine-stroke Leakage from the back-pressure system that is, the system supplying pressure on the back or lower side of piston ill and tending to lower the compensating pressure-is provided so as to gradually reduce the back pressure in case the tappet does not open the valve 19, this result being secured in the construction shown by an adjustable needle-valve 2 on pipe 23, which permits a small constant leakage of air and by which the amount of such leakage may be adjusted. The safety-valve 14 is set so as to blow oil at the desired point and prevent the back pressure rising too high in case ol. an excess admission of air through pipe 23.

The operation of the construction will be understood from a brief description in. connection with the drawings. The tappet 15 engages the valve-rod l8 and. opens the valve 19 at the end of each stroke of full length in one direction, so as to admit air "rom airchamber 1) to the back-pressure system. The tappet 15 and the valve 2 are so adjusted. that on the normal stroke of the engine the valve 19 is opened by the tappet only for such a time as to compensate for the leakage from the back-pressure system. through valve 2, and thus maintain a uniform load on the accumulator-cylinders F, or it the stroke be too long the valve 19 will be open for a longer time and more air admitted to the backpressure system, with the result that the pressure in the back-pressure system is increased and the compensating-cylinder load slightly reduced, which will tend to shorten the stroke of the engine and gradually bring the engine back to normal stroke. it hen by reason of shortened stroke the tappet fails to open the valve 1%), the pressure of air in the back-pressure system drops gradually on account of the leak through the valve 2, and as the back pressure decreases the compensating-cylinder load increases and the stroke is gradually lengthened. By adjusting the taptpe 15 and the valve 2 a practically-constant stroke of the engine may readily be secured.

It will be understood that the invention is not limited. to the particular arrangement or construction of engine and compensating system shown nor to the particular devices shown for adjusting the compensating pressure, but that the invention as defined by the claims may be embodied in constructions of widely-diflerent forms.

will at I claim is* 1. Ti e combination with a tlirect-acting engine, oil one or more compensating cylinders and pistons acting in opposition to tilt on gine-piston during the first part of the stroke and in conjunction tncrewitn during the last part of its stroke, means for applying motor iluid in opposition to the working pressure lor adjusting the compensating-cylintler pressure, and means coi'itrolled by the lengt 2i oi toe engine-stroke l or varying the rclai' iyc working and opposing pressures to vary the co]npensating-cylinder pressure.

2. The combination with a direct-acting engine, o'l one or more compensating-cy'lii1- dcrs and pistons acting in opposition to toe engine-piston during the lirst part ot the stroke and in. conjmiction therewith during t re last part ol its stroke, and means controlled by trse length of the engine-stroke lor admittir fluid to the compensating system inv opposition to toe working pressure to 'ary the compensating-cvlindcr pressure.

3. Tie combination witn a dirccbacting engine, of one or more compensating cylinders and. pistons acting in opposition to the engine-piston during the first part ol' tilt stroke and. in conjunction trerewitn durim: tre last part of its stroke, means controlled by tile lcngtn oi tiie engine-stroke l or adn1itting :lluid to the compensating system at eacn stroke of the engine of normal or greater lei'lgtli, and an outlet from the system lor [to constant escape of fluid from the compcn-- sating system.

4-. Tile combination with a direct-acting engine, of one-or more compensating cylinders and pistons acting in opposition to l'l engine-piston during trio first part ol lixc stroke and in conjunction therewith during the last part of its stroke, means controlled by the length of ti e engine-stroke l'or admitting lluid to the compensating system in oppositionto the Working pr rsurc at each stroke oil the engine of normal or greater length, and an outlet from the system for tire escape ol fluid to lessen the opposition to the working pressure.

5. The combination with a direct-rudiug engine, of one or more compensating cylin ders and pistons acting in. opposition to the e1'1gine ')iston during the first part of tinstroke and in conjunction toerewitn during tire last part of its stroke, an accumulzuor tnrougn wnich said. compensating cylinder derives its pressure, and means controlled by the length of the engine-stroke for admitting :l'luid to said accunnilator in opposition to the working pressure to vary the compei'isatingcylinder pressure.

6. Tire combination with a dircctacting engine, of one or more compensating cylinders and pistons acting iii-opposition to the engine-piston during the 'lllSlZ part of the stroke and in conjunction therewith during adjustable outlet permitting a constant esthe last part of its stroke, an accumulator through which said compensating cylinder derives its pressure, a pipe for admitting fluid to said accumulator in opposition to the working pressure, an outlet permitting a constant escape of fluid from the back-pressure system, and a valve opened by the main piston on each stroke of normal or full length for admitting air to the back-pressure system.

7. The combination with a direct-acting engine, of one or more compensating cylinders and pistons acting in opposition to the engine-piston during the first part of the stroke and in conjunction therewith during the last part of its stroke, an accumulator through which said compensating cylinder derives its pressure, a pipe for admitting fluid to said accumulator in opposition to the working pressure, an outlet permitting a constant escape of fluid from the back-pressure system, a tappet moving with the engine-piston, and a valve engaged by said tappet on each stroke of normal or full length to open tFi e valve for the admission of air to the backpressure system.

8. The combination with a direct-acting pumping-engine and its air-chamber, on the force-main, of one or more compensating cylinders and pistons acting in opposition to the engine-piston during the first part of the stroke and in conjunction therewith during the last part of its stroke, an accumulator through which said compensating cylinder derives its pressure from the air-chamber, a pipe for admitting fluid to said accumulator in opposition to the working pressure, an outlet permitting a constant escape of fluid from the back-pressure system, a tappet moving with the engine-piston, and a valve engaged by said tappet on each stroke of norma or full length to open the valve for the admission of air to the back-pressure system.

9. The combination with a direct-acting engine and its compensating cylinder or cylinders and accumulator, of pipe 23 connecting the back-pressure side of the accumulatorpiston with a source of pressure fluid, and a valve controlling said pipe and controlled by the length of stroke of the enginepiston.

10. The combination with a direct-acting engine and its compensating cylinder or cylinders and accumulator, of pipe 23 connecting the back-pressure side of the accumulator-piston with a source of pressure fluid, an

cape of fluid from said pipe, a valve controlling said pipe, and adjustable means moving with the engine-piston for admitting fluid through said pipe at each normal or longer stroke of the piston.

11. The combination with a direct-acting engine and its compensating system, of a valve for admitting fluid to the compensating system to vary the compensating pressure, and means moving with the engine-piston for actuating said valve.

12. The combination with a direct-acting engine and its compensating system, of an outlet permitting the constant escape of fluid from the compensating system, a valve for admitting fluid to the compensating system to vary the compensating pressure, and means moving with the engine-piston for opening said valve for the admission of fluid.

13. The combination with a direct-acting engine, of a compensating piston acting in opposition to the movement of the enginepiston during one part of the stroke and in conjunction therewith during another part of the stroke, means for applying motor fluid in opposition to the working pressure for adjusting the compensating-cylinder pressure, and means controlled by the length of the engine-stroke for transferring fluid from the working-pressure fluid to the fluid opposing the working pressure to vary the compensating-cylinder pressure.

14. The combination with a direct-acting engine, of a compensating cylinder having a piston acting in opposition to the movement of the engine-piston during one part of the stroke and in conjunction therewith during another part of the stroke, means controlled by the length of the engine-stroke for transferring fluid from the working-pressure fluid to a supply of fluid working in opposition to the working pressure at each stroke of the engine of uniform or greater length, and an outlet from the system for the escape of fluid to lessen the opposition to the working pres sure.

In testimony whereof I have hereunto set my hand in thepresence of two subscribing witnesses.

l/VILLIAM C. BROWVN.

Witnesses:

J. A. GRAVES, V. H. KENNEDY.

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