US972218A - Controlling device for pressure-fluid engines. - Google Patents

Description

A. E. N ORRIS. GONTEOLLING DEVICE EoR PRESSURE FLUID ENGINES. APPLIO'ATION FIL-BD IBB. 10| 1909.

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, UNiTED sTATEs PATENT oEEioE.

ALMONVE. NORRIS, 0F CAMBRIDGE, MASSACHUSETTS.

CONTROLLING DEVICE FOR PRESSURE-FLUID ENGINES.

Specification of Letters Patent.

Original application led January 18, 1908, Serial No. 411,466. Divided and this application filed February io, i909.

To all 'whom it may concern: l

Be it known that I, ALMON E. NoRRIs, a citizen of the United States, residing at Cambridge, in the county of Middlesex and State of Massachusetts, have invented an Improvement in Controlling Devices for Pressure-Fluid Engines, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to controlling devices for pressure fluid engines, the same being shown as embodied in the form of a steam engine throttle valve.

The present application, as to certain features, is a division of my prior application, Serial No. 411,466, filed January 18, 1908.

My invention will be best understood by reference to the following description when taken in connection with the accompanying drawings showing one specic embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

In the drawings: Figure 1 is a central,

sectional elevation showing a throttle valve embodying one form ot my invention; Fig. 2 is a similar View showing the throttle valve in a diierent position from that shown;

in Fig. l; Fig. 3 is a sectional detail in plan on the line 3 3 in Fig. 1; Fig. 4t is a sectional detail in plan on the line i-4 in Fig.

1; and Fig. 5 is a diagrammatic view in ele-.

vation showing the application of the described orm of throttle valve to a steam engine.

Referring to the embodiment of my inven.

tion shown in the drawings and rst more particularly to Fig. 5, I have there shown conventionally a steam engine having the cylinder 1 to which leads the supply pipe 2, in which is interposed the throttle valve 3. If an ordinary throttle valve were employed, as soon as steam were shut off from the engine cylinder a certain amount of pressure iuid would be trapped and remain in the cylinder. Such would be apt to cause a creeping or continuation of the engine movement if the throttle were closed to stop the engine, due to the expansion of the trapped pressure fluid within the cylinder, or if it were desired to allow the driven member to turn the engine backward, it would act to prevent such free backward movement. For certain classes of work this engine creeping movement after the pressure supply has been Serial No. 477,060.

shut off is undesirable, and, in many cases,

Patented Oct. 11, 1910.

I have herein associated A with the engine a throttle valve of improved A construction and such that, when closed, it not only shuts otf the pressure supply from the cylinder but relieves the pressure within the cylinder by opening the latter to the ex-v haust sufficiently to clear the cylinder of the trapped pressure fluid, rendering the engine ineifective for moving the driven part and leaving it free to be driven backward by the driven member or load. In the form herein shown such throttle valve consists of the main body or casing t having an interior chamber adapted to receive the sliding throttle valve member 5.

The supply pipe 6 (Fig. 5) is connected to the supply or entrance opening 7 of the valve casing, which latter opens into an annular chamber 8, the latter having the supply port 9 controlled by the lower edge or wall of the valve member 5. When the valve member is lifted to the position shown in Fig. 2, steam can pass from the supply chamber 8 through the port 9 to the lower part of the valve chamber, whence it passes through the connecting passage 10 to the v Aexit opening 11 of the valve casing and thence, through the supply pipe engine cylinder.

In order to connect the engine cylinder with the exhaust, when the valve is closed, the valve member is constructed in the form of a hollow cylinder through which the lower end of the valve chamber, and hence the exit passage 11, may be connected with an annu- 2, to the lar exhaust chamber 12, the latter surrounding the valve member 5 near its upper end, such exhaust chamber having connection, through the exhaust opening 13, with the exhaust pipe 14 (see Fig. 5). Referring more particularly to the detailed construction ot' the valve member, the cylindrical shell oi' the latter is stitfened both at the top and the bottom by tour radial webs 15, the cylindrical walls of the shell being also strengthened by tour longitudinal ribs 16 which extend lengthwise the shell on the inside thereof and connecting the ends of the web 15. The shell is surmounted by the arched piece 17 suitably attached to the stem 18 and of such dimensions that it readily passes 'within the contracted opening 19 in the end of thevalve chamber, such'openinghowever (as shown .in Fig. 2), closely fitting the valve shell when the latter 1s lifted.

The upper end-of the valve casing is closed by a suitable cap 20 carrying the packing 'gia-nd 21', .through which passes :the valve. stem 18. The end of the stemY is provided with the eye 22 to which may be secured any suitable form of valve-actuating device, there being preferably provided the collar v23 adjustably fixed on the stem and abutting @against the compression spring 24, the op- Apositefend of which latter abuts against the fixed yoke or plate 25 secured to the upright rods 26 which are secured to the cap .20. The spring, therefore, normally acts to lclose the valve, moving thesame to the position ushown in Fig. 1 where the nut 27,

1 pinned to the stein 18, is seated against the fixed plate 25. With the valve depressed as shown in Fig. 1 admission of steam is cut off fromthe lower end of the valve chamber by reason of the closure of the admission port`9 while, at the same time, the exhaust chamber 12 is opened to the interior of the I valve and thereby to the pipe 2 and the cylinder space by reason of the depression of the upper wall or edge of the shell below thecontracted chamber opening 19. The trapped pressure fluid in the cylinder, therefore, readily passes out from the cylinder through Vthe pipe 2, -admission opening 11, Y passage 10, to the valve chamber, and from Y upper edge of the valve,

the valve chamber through the interior of the shell to the'exhaust chamber about the as represented by the arrows in Fig. 1. When the stem is lmovedup to lift the valveto the position represented in Fig. 2, the exhaust chamber Vis out olf from communication with the interior of the valve by the entrance of the upper edge or wall of the shell within the contracted wall portion 19. v

It is to be observed that the upper end of the valvechamber within the cap 20 is at Y all times in free communication with the lower end of the valve chamber through the Vhollow interior of the valve interiorv of the valve wit whether the lattermbe positioned as in Fi 1 to connect the l the exhaust, or positioned as in Fig. 2 to connect the valve i interior with the pressure supply.

nected as Vto effect, when closed, a double connection with the exhaust. For this purpose herein the shell of the valve is provided VVwith an intermediate-port 29, herein in the Les form' of a circumferential groove cut entirely through the walls of thev shell except at the four ribs 16, which latter, in the vicinity of the port 29, arethickened asshown to strengthen the shell at that aoint.

In the depressed position o the valve represented in Fig. 1 pressure fluid is permitted .freely-to pass out from the interior of the valve to the exhaust chamber 12 through the port 29, thereby acting to supplement the exhaust which is effected about the upper edge of the valve and acting therefore instantaneously to relieve the pressure trapped within the cylinder and maintain the latter open to the atmosphere. In the upper position of the valve (Fig. 2), the port 29 is cut off from communication with the exhaust chamber by entrance into a closely fitting opening provided in a wall portion 30 projecting laterally from the valve casing into the exhaust chamber 12.

Opposite ends of the valve chamber being in communication at all times, the valve rcmains in an approximately balanced condition. In order to render the valve completely balanced there is provided the stem portion 31 projecting downwardly from the valve member and secured centrally thereto at the junction point of the radial webs 15. The stem 81 asses through a closely fitting opening in tiie lower wall 32 of the valve chamber, where its end is exposed to the pressure within the balancing chamber 33, which latter, however, is connected by the passage 84C with the exhaust chamber 12 and the exhaust pipe 14. The cross-sectional area of the stem 31 being substantially the same as that of the main valve stem 18, the valve member remains at all times in a condition of balanced pressure.

While I have herein shown and described one specific form of my invention and one specific application thereof for the purposes of illustrating it in concrete form, it is to be understood that the invention is not limited to the details of construction or the specific relation or arrangement of parts, but that extensive deviations may be made from the form described herein contained without departing from the spirit of the invention.

Having thus described one form of my invention, what I claim is:

1. The combination with a pressure fluid engine, of a controlling device therefor having means for connecting said engine with or disconnecting the same from a source of pressure iiuid and also means for simultaneously connecting the said engine with the exhaust at the time of its disconnection from the pressure Huid supply, thereby to relieve the engine of the pressure fluid trapped therein.

2. The combination with a pressure Huid engine, of an engine throttle valve connected in the supply pipe therefor, said valve having means for relieving the pressure trapped in said engine when said throttle valve is closed.

3. A throttle valve provided with a valve chamber, a hollow cylindrical valve member adapted to move therein, a cylindei` admission opening communicating with one end of said valve and adapted to be placed in communication with a pressure fluid supply chamber when said valve is moved axially, and an exhaust opening adapted to be placed in communication with the opposite end of the valve when the latter' is moved to a closed position.

4C. A throttle valve having a valve chamber, a hollow valve, an exhaust chamber, a pressure supply chamber and a cylinder chamber, said valve being connected to open communication between the cylinder chamber and the exhaust chamber about one edge of the valve, when in one position, while cutting off communication between the cylinder chamber and the pressure supplychamber, and, in another position, to open the cylinder chamber to the pressure supply chamber about the opposite edge of the valve, while cutting off communication between the cylinder chamber and the exhaust chamber.

5. A throttle valve having a valve member provided with a cut-olf wall for cutting olf a suitable pressure fiuid supply chamber from, or opening the same to, the valve chamber, and provided also with a plurality of cut-olf walls for simultaneously opening the valve chamber to the exhaust or cutting off the same from communication therewith.

6. A throttle valve having a valve chamber, a hollow cylindrical valve member adapted to slide therein, the opposite ends of the valve chamber being in free communication through the hollow interior of the valve, and the valve chamber being in communication with the supply pipe of the engine or other apparatus in connection with which said valve is employed, an exhaust chamber adapted in one position of the valve to be opened to the valve chamber about one edge of the valve, and a pressure fluid supply chamber adapted in another position of the valve to be opened to said valve chamber about the opposite edge of the valve.

7. A throttle valve comprising a valve member adapted to be moved to shut off the supply of pressure fluid from the supply opening of the valve, and simultaneously to connect the same with the exhaust, and pressure balancing means for said valve.

8. The combination with a pressure fluid engine having a supply pipe of controlling means therefor in the supply pipe, the same comprising a single movable controlling member for simultaneously connecting the engine with the exhaust and disconnecting the engine from the pressure fluid supply or vice versa.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

ALMON E. NORRIS.

itnesses THOMAS B. BOOTH, IRvING U. ToWNsEND.

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