US2180144A

US2180144A - Control mechanism

Info

Publication number: US2180144A
Application number: US138467A
Authority: US
Inventors: Gieseler Martin
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1936-05-12
Filing date: 1937-04-22
Publication date: 1939-11-14
Anticipated expiration: 1956-11-14

Description

Nov. 14, 1939. M @ESELER 2,180,144

CONTROL MECHANISM Filed April 22, 1957 T0 Pqnvr 0F HIGH PREssl/RE Inventor: Martin Gieseler,

H is ttonney.

Patented Nov. 14, 1939 UNITED STATES PATENT OFFICE CONTROL MECHANISM New York Application April 22, 1937, Serial No. 138,467 In Germany May 12, 1936 6 Claims.

My invention relates to control mechanisms, more specifically to arrangements in which a pump or like machine is alternately driven by an electric motor and an elastic fluid turbine. The

rotor of such turbine is normally rotated during operation of the electric drive. Such rotation causes little loss as long as vacuum is maintained. in the turbine as is the case where the turbine is connected to a condenser, in other words, as

long as such turbine is operated as a condensing turbine. If, however, such turbine is operated as a noncondensing turbine, more specifically as a back pressure turbine for supplying elastic fluid under a certain pressure to a point of consumption, then the loss due to friction within the turbine during operation of the electric drive becomes inadmissible.

The general object of my invention is to provide an improved arrangement for control mech- 90 anisms for pump drives including a back pressure turbine whereby the aforementioned losses during operation of the electric drive are substantially eliminated. This is accomplished in accordance with my invention by the provision of 25 a two-way valve in the exhaust conduit of the back pressure turbine and means for operating the valve to connect the exhaust conduit of the back pressure turbine to a point of consumption during turbine operation and to a point of low 30 pressure, for instance, the atmosphere, during operation of the electric drive. In a preferred embodiment, I provide means for automatically operating the two-way valve in conjunction with the operation of the inlet valve to the turbine.

35 For a better understanding of what I believe to be novel and my invention, attention is directed to the following description and the claims appended thereto in connection with the accompanying drawing.

4 The single figure of the drawing shows a pump drive embodying my invention.

The arrangement includes a centrifugal type pump I!) which is alternately driven by an electric motor H connected to a power line 12 by a switch l3 and by an elastic fluid turbine l4 mechanically connected to the pump shaft by a gearing I5. The turbine H has an inlet valve [6 and an exhaust conduit I! which may be connected by a two-way valve I8, either to a conduit l9 leading to a point of high pressure or to a conduit leading to a point of low pressure. During operation of the electric motor the valve I6 is closed and the valve I8 is in the position indicated connecting the conduit l! to a point 55 of low pressure, for instance, the atmosphere.

ill

During turbine operation, the valve position I8 is reversed so that the exhaust conduit I7 is connected to a point of high pressure, that is, a point of consumption. As pointed out above, in a preferred embodiment as shown in the drawing, means are provided for operating the two-way valve l8 simultaneously with the operation of the inlet valve it. These means comprise a hydraulic motor 2i having a piston 22 connected to the two-way valve l8, and another hydraulic motor 23 having a piston 24 connected to the admission valve 16. Fluid under pressure is conducted to the motors 2i and 23 by means of

conduits

25 and 26 and the flow of operating fluid is controlled by a pilot valve 2'17 which has a stem 28 connected to the left-hand end of a lever 29 having an intermediate point held on a fulcrum 38 and a right-hand end connected to a solenoid 3.! and biased in downward direction by a spring 32. The solenoid has a coil 33 energized by a device 34 responsive to the flow of electric energy to the motor ll. In the present instance, the switch I3 is closed and energy is supplied to the motor ll so that the solenoid 3| is energized, forcing the right-hand end of the lever 29 in upward direction against the biasing force of the spring 32. Under such condition the stem 28 of the pilot valve is forced downward to hold the pilot valve heads in the position indicated in the drawing. In this position of the pilot valve, operating fluid under pressure is conducted through the pilot valve and the conduit 25 to the right-hand end of the hydraulic cylinder 2| and to the lower end of the hydraulic cylinder 23. Simultaneously operating fluid is discharged from the left-hand end of the hydraulic cylinder 2| and from the upper end of the hydraulic cylinder 23 through the conduit 25 and the pilot valve. This effects closing of the turbine inlet valve 16 and disconnecting of the turbine exhaust conduit H from the conduit 19 and connecting said exhaust conduit with the conduit 26. If for some reason the motor I! should fail, the solenoid 3| will be de-energized and the lever 29 turned in clockwise direction by the action of the spring 32, thus reversing the position of the heads of the pilot valve 2'! and also reversing the position of the

pistons

24 and 22 of the hydraulic motors 23 and 2! respectively, to the effect that the turbine inlet valve 16 is opened and the position of the two-way valve 18 is reversed.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. The combination of a pump, an electric motor and a back pressure turbine for alternately driving the pump, the turbine having an admission valve and an exhaust conduit, means including a two-Way valve connecting in one position the exhaust conduit to a point of low pressure and in the other position to a point of high pressure, and means for simultaneously positioning the admission valve and the two-Way valve upon failure of the electric motor.

2. The combination of a machine, an electric motor and a back pressure turbine for alternately driving the machine the turbine having an admission valve and an exhaust conduit, and a control mechanism for maintaining the admission valve closed and simultaneously connecting the exhaust conduit to a point of low pressure during operation of the motor and for opening the admission valve and simultaneously connecting the exhaust conduit to a point of high pressure upon failure of the electric motor.

3. The combination of a pump, an electric motor and a back pressure turbine for alternately driving the pump, the back pressure turbine having an admission valve and an exhaust conduit, means including a two-way valve and conduits connected to the exhaust conduit for connecting the exhaust conduit to a point of high pressure during turbine operation and to a point of low pressure during motor operation, and means for automatically opening the admission valve and moving the two-way valve in response to change from motor operation to turbine operation and vice versa, said last-named means including hydraulic motor means connected to the admission valve and to the two-way valve, a pilot valve for controlling the flow of operating fluid to the hydraulic motor means, and a solenoid connected toand moving the pilot valve upon energization and de-energization of the motor.

4. The combination of a machine, a motor and a back pressure turbine for alternately driving the machine, the turbine having an admission valve and an exhaust conduit, and a hydraulic control mechanism electrically connected to the motor for automatically connecting the exhaust conduit to a point of high pressure during operation of the turbine and disconnecting the exhaust conduit from the point of high pressure and connecting the exhaust conduit to a point of low pressure upon failure of the turbine and during operation of the motor.

5. The combination of a machine, a back pressure turbine and another power agency for alternately driving the machine, the turbine having an admission valve and a branched exhaust conduit with a first branch for connecting the exhaust end of the turbine to a point of high pressure and a second branch for connecting the exhaust end of the turbine to a point of low pressure, and valve means for controlling the flow of exhaust fluid through the branches to effect discharge of the exhaust fluid through the first branch during operation of the turbine and through the second branch during operation of the other power agency.

6. The combination of a machine, an electric motor and a back pressure turbine for alternately driving the machine, the turbine having an admission valve and a branched exhaust conduit with a first branch for connecting the exhaust end of the turbine to a point of high pressure and a second branch for connecting the exhaust end of the turbine to a point of low pressure, valve means for controlling the flow of exhaust fluid through the branches, and a mechanism connected to the admission valve and the valve means for simultaneously reversing the valve means and closing the admission valve in response to starting of the motor.

MARTIN GIESELER.