US1796508A - Automatic stop for steam turbines and the like - Google Patents

Description

March 17, 1931. c. w. DAKE 1,796,508

AUTOMATIC STOP FOR STEAM TURBINES AND THE LIKE Filed Oct. 7, 192 4 Sheets-Sheetv l [IE| l BY /z ATTORNEYS.

March 17, 1931.

' c. w. DAKE 1,796,508

AUTOMATIC STOP FOR STEAM TURBINES AND THE LIKE Filed Oct. 7, 192

4 Sheets-Sheet 2 INVENTOR ATTORNEYS March 17, 1931. c w DAKE 1,796,508

AUTOMATIC STOP FOR STEAM TURBINES AND THE LIKE Filed Oct. '7, 192' 4 Sheets$heet 5 INVENTOR ATTORi'v'EYS March 17, 1931. c. w. DAKE 7 8 AUTOMATIC STOP FOR STEAM TURBINES AND THE LIKE Filed Oct. 7 192 {Sheets-Sheet 4 INVENTOR ATTORNEYS Patented Mar. 17, 1931 STATES GHARLES W. BAKE, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE PYLE NATIONAL COM- PANY, 0F CHIUAGG, ILLINOIS, A CORPORATION OF NEW JERSEY AUTOIVIATIC STD? FOR STEAM TUEBIIIES AND THE LIKE Application filed October 7', 1927. Serial No. 224,592.

My invention relates to im rovements in automatic stops for steam turbines and the like and has for one object to provide an automatic stop located within the turbine housing which will automatically break the steam line when the speed of the turbine exceeds a predetermined point and compel the operator to open the turbinebefore op eration can be resumed. The purpose of this is, of course, to compel the operator to get at the inside of the turbine when it is comparatively easy to resist the governor to control the speed and thereby prevent long continued unauthorized operation of the turbine at improper high speed. Other objects will appear from time to time in the specification and claims.

My invention is illustrated more or less diagrammatically in the accompanying drawings, wherein Figure 1 shows a side elevation of the governor end of. a turbine;

Figure 2 shows a section along the line 2-2 of Figure 1; I

Figure 3 is a section along the line33 of Figure 2;

Figure shows a detail on an enlarged scale of the cut oil piston with the piston in elevation;

Figure 5 is an enlarged scale view in elevation of the shut off capsule;

Figure 6 is a section on an enlarged scale showin the centrifugally operated release member.

A is a turbine housing having an exhaust pipe A and a steam supply pipe A A is the governor housing removably bolted onto the turbine housing and closing one side thereof. A is a cover plate covering the opposed end of the governor housing. A is the turbine shaft, the bearings not being here shown. Mounted on the shaft is a turbine wheel comprising a hub A, web A and buckets A the axle not being shown. A is a guide passage through which steam discharged from the buckets is returned thereto in the usual manner.

B is a governor cap threaded on the end of the turbine shaft. It terminates in a reduced shaft B on which is slidably mounted a sleeve 13 B is an anchor ring surrounding but out of contact with the sleeve and held on the governor cap by means of thescrews B. B is an abutment ring engaging the anchor ring B and attached to the inner end of the governor spring B The outer end of the spring B is attached to the holding ring B which ring engages 'a shoulder on the sleeve B and tends to thrust the sleeve inwardly. B is a governor weight fulcrumed about a knife edge as shown on the cap B, the outer end being weighted, the inner end engaging the sleeve B As the shaft rotates centrifugal force tends to throw the weighted ends out and move the sleeve toward the right'as shown in Figure 3.

C is a wear plate engaging the end of the sleeve B This wear plate is mounted in a socket C threaded in a holding ring C in the governor bell crank lever C C is a latch whereby the plug G can be moved toward and from the governor sleeve B to adjust the speed of the turbine. The other end. of the bell crank lever C engages the valve stem C to move the steam throttle valve C up and down on its seat to control the flow of steam. C is a spring resisting the movement of the governor stem and holding it against the lever C C is a cap closing the valve pocket and enclosing the the removable socket therein which contains the valve. C is a spring seating the removable socket in its air pocket.

D is the housing for the automatic stop thereof. It is bolted onto the governor housing. Steam passes from the pipe A through the passage D through the port D passageD to the valve C, as long as the parts are in the position shown in Figure 2. D is a piston valve slidable in its seat in the housing D. D is a spring tending to yieldingly urge the valve in to the open unobstructed position. There is a certainamount of leakage around both sides of this valve so that the valve is to all intents and purposes a balanced valve, the pressure befill ing balanced on both sides of the valve pistons permitting the spring to hold the valve open and permitting steam to flow without restriction to the governor controlled throttle valve. l) a passage lead ing from one side oi: the valve D* to a threaded thimble or capsule D". This ble or capsule D extends out toward the valve wheel.

E is a stop ring mounted on the governor cap B. It has an arm E adapted to contain a set screw E and lock plug E whereby it may be held against rotation on the shaft or governor cap. Ff is the opposed arm containing a spring This arm is apertured at E. E is a cutter bar slidable in the hole E and ten. uatirg in a plunger E E is a spring in erposed between the plunger E and the outer end of the arm E and holding it in the full line'position. E is a stop pin, the shaft E being cut away and provided with a shoulder E which will engage the stop pin when the shaft is on its outer position to limit its outward excurtion. It will be noted that when the parts are in the full line position shown in Figure 6, the cutter blades E do not come in contact with the capsule D but it the speed rises to such a point as to permit the spring to be overcome, the cutter blades are forced out and as the turbine rotates they engage the thin walls of the capsule D and break them open thus permitting steam to pass from the passage D out into the turbine without cutting through the nozzle. Since the turbine is at exhaust pressure no steam will pass through the nozzle and the turbine will stop because the reduction in pressure in the chamber and passage D down to exhaust will cause the pressure of steam in the passage D to move the stop valve toward the left as shown in Figure 4 to or toward a position where the outer end of the valve at F will close the passage D" and completely cut 01? the steam. No matter what is done to the steam line all steam which passes through will immediately wing to the unbalanced condition of the stop valve cause that valve even though the spring may not return it when steam is oft, to the starting position to shut oi"? the steam before it reaches the governor. The only waythe operator can start the turbine then is to take off the cover and screw a new capsule in and when he does this, since the governor mechanism is there at his hand, he will also make the proper adjustment because he knows it is easy to do this and if he does not do it the same thing will happen over again and he will have to put a new capsule in. This makes it impossible for an operator to operate a turbine with a dangerously improper adjustment as might be the case if it were possible to continue operation at excessive speeds.

It will be noted that the purpose of the arm opposed to the cutter blade carrying arm is merelv to provide means for locking the stop member in position on the governor cap to balance the parts and to make it possible to easily assemble the device. For assembling the spring is put in the plunger and cutter bar is put in, dropped down to the bottom of the working arm and then threaded on the shaft. After that the set screw is put in place and the parts are in proper assembled position.

I claim:

1. The combination with a fluid turbine of a throttle valve, a speed governor adapted to control it, a motive fluid line controlled by the valve, a housing for the governor, a. capsule commimicating with the motive fluid line which furnishes the motive fluid to the motor located within the housing and means associated with the turbine tor nan; the capsule when a. predetermined speed has been reached.

In combination with a steam turbine, L steam line, a governor throttle valve there r, a stop valve in the steam line compris a bananced piston, a housing for the *ernm', a capsule communicating with one no of the balanced valve and subject to steam, pressure, means associated with no turbine for rupturing the capsule when predetermined speed has been reached, the capsule being renewable only by opening the governor containing housing.

Signed Chicago, county of Cook and State of Illinois, this th day of October, 1927.

CHARLES WV. DAKE.

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