US2397213A

US2397213A - Regulating apparatus

Info

Publication number: US2397213A
Authority: US
Inventors: Walter H Smith
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1942-05-20
Filing date: 1943-05-07
Publication date: 1946-03-26
Anticipated expiration: 1963-03-26

Description

March 26, 1946. wf H. SMITH REGULATING APPARATUS Original Filed May 20, 1942 ATTORNEY Patented Mar. 26, 1946 REGULATNG PPRTUS Walter H. Smith, Wilkinsburg, Ta., assigner to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsyivania Original application May 20, 1942, Serial No.

443,689. now Patent No. 2,340,994, dated February 8, 1944. Divided and this application May 7, 1943, Serial No. 486,009

7 Claims.

This invention relates to regulating apparatus for constant speed machines, engines, and/or other motor means particularly to regulating apparatus for maintaining the operating characteristics of such machines constant.

This application is a division of my application led May 20, 1942, Serial No. 443,689, entitled Regulating apparatus, issued as Patent No. 2,340,994 on February 8, 1944.

In the operation of Diesel electric locomotives for example, it is necessary to provide for load regulation to prevent overloading of the Diesel engine. Many types of load regulating apparatus have been provided heretofore but they have had certain disadvantages. The diierent types of known load regulating apparatus are complicated and have large moving parts thereby necessitating more space for mounting the regulating apparatus and greatly adding to the cost of the installation. Another disadvantage of the known types of regulators is that hunting is encountered whereby the control is not suciently sensitive to meet given conditions.

An object of this invention is to provide for operating machines, motor means or engines at substantially maximum capacity and constant speed.

motor means, to maintain the operation of such engines, or motor means, at substantially maximum capacity and substantially constant speed.

It is also an object of my invention to provide speed governor controlled valve means for controlling the flow of fluid from a source of fluid pressure to further control means for controlling the operation of a machine.

Other objects of the invention will become apparent from the following description when taken in conjunction with the accompanying drawing, in which:

Figure 1 is a view in elevation and partly in section of control apparatus employed in this invention;

Fig. 2 is a view in elevation and partly in section of another embodiment of part of the control apparatus employed in this invention; and

Fig. 3 is a schematic view of the regulating apparatus of this invention.

Referring to Fig. 3 of the drawing, a preferred embodiment of the regulating apparatus is illustrated applied to a Diesel engine IB. The Diesel engine ID is of the usual type having hand or power operated throttles (not shown) for controlling the operation of the engine and a hydraulic speed governor l2 for preventing over-loading of the engine, as will be explained more fully hereinafter. The details of the hydraulic governor l2 are not illustrated as they are well known, the easing of such hydraulic governors including a pump for supplying lubricant under pressure to a point in the system where required.

A generator I4 provided with an armature winding I6 and a field winding I8 is driven by the Diesel engine l0. The armature windings le are `32 and an adjustable field rheostat 34 to be energized from a suitable source of power, such as the battery 36. The carbon pile resistor 32 and the operating mechanism therefor are better shown ln Fig. 1.

In this application I do not limit my claims to the particular scheme shown in Fig. 3 or the use of the carbon pile resistor 32. The resistor 32 represents any kind of machine the operation of which is to be controlled. For instance the

elements

42 and 60, discussed more in detail hereinafter, may represent the brush shifting mechanisms of a series motor used to propel a torpedo. In this connection attention is called to my copending application led July 23, 1943, Serial No. 496,415, and entitled Torpedo controls.

The resistor 32 may be of any of the well known types and in this embodiment is illustrated as comprising a stack of carbon discs 38 slidably mounted on an insulated rod 40 between

pressure discs

42 and 44. the assembly being mounted between support members 46 and 48. Although only one stack of discs 38 is visible in the drawing, usually two or more stacks connected in series circuit relation are utilized and are so mounted on insulated rods 40 associated therewith that an equalized pressure can be' applied simultaneously to each stack, The ends of the rod 40 of each of the stacks are slidably mounted in the support members 46 and 48. A spring member 50, disposed between support 46 and the nut and washer arrangement 5ll' on the left end of the rod 40, is provided for normally biasing the rod 40 to the left with reference to supports 46 and 48.

A pressure applying lever 52 is pivotally carried by an anchor stud 54 which is secured to a lug 56 carried by the support member 46. A pressure spring 53 is positioned between the lug 6G and the lever 52 for normally biasing the lever E32 to apply pressure to the cross bar @El where more than one stack is employed, or directly to the end cap of the pressure disc i2 to compress the stack of discs. Carbon pile resistors of this general type are disclosed and claimed in my Patent No. 2,276,069, issued March l0, 1942, and assigned to the assignee of this invention.

ln order to alter the pressure on the stack of discs 38, a control valve member 62, an auxiliary control valve member 6d and a power piston member 66 are provided for so cooperating in response to a decrease in the speed of the engine i8 as to apply an intermittent change or" pressure to the end of the lever 52 in opposition to the pressure of the spring 58.

The control valve member 6i? is disposed to be mounted on the casing of the hydraulic governor i 2 and comprises a sleeve member having a g piston valve member 'I8 slidably disposed therein. The piston valve member 16 is formed of the valve ,'52 intermediate of the closure members lll and i6, which cooperate therewith. in forming two chambers i8 and 86. rlhe stein 62 of the piston valve member 'i6 extends through an oil gland 84 at the lower end of the casing member 66 and terminates in a position where it is disposed to be engaged by the actuating lever of the hydraulicgovernor i2- in a predetermined manner. The upper end of the casing member 66 is closed by means of the threaded cap member 63 forming a reservoir with the end of the piston valve member 10, a spring member S36 being disposed between the end cap member 88 and the upper end of the piston valve member 'i6 for normally biasing the piston valve member downwardly in the casing member. As illustrated, a passage 92 is provided extending from the end of the piston valve member in the reservoir and terminating in the opening 84 which communicates with a drain chamber 96 provided in the lower end of the casing member.. An opening 68 is also provided in the piston valve member i6 communicating between the chamber it and the passage 82 for draining the lubricant from the chamber 'I8 under predetermined conditions. An inlet passage |08 is provided in the casing member 68 and is connected to the hydraulic gover- 'nor I2 for supplying the lubricant to the chamber 88 under pressure. An outlet passage or port H62 is also provided in the casing member 6d for cooperating with the valve l2 for controlling the outlet of the lubricant from the control valve member 62 or the draining of the lubricant from the power piston member 66 as will be explained more fully hereinafter.

The auxiliary control valve member-6d comprises the casing member it having a rotary valve member |66 disposed therein with its stem Hi8 extending through an oil gland il@ at the lower end thereof. the rotary valve member I86 is disposed to be connected either directly or through a suitable gear chain (not shown) to the crankshaft of the Diesel engine i0, and is operated in accordance with the speed of the engine Il). As illustrated, the rotary valve member I06 has a passage Il il therethrough which is disposed to be aligned with the ports in the casing member IEM for a given position of the rotary valve member H86. The passage II2, however, may be of any form, depending upon the location of the ports inl the casing member i84. In addition to being a single passage li2 as illustrated, a plurality of passages The stem member Hilti of asevera through the rotary valve member itt may be provided, depending upon. the number of desired admissions, one or more, of the lubricant through the auxiliary control valve member 64 per revolution. of the engine iii. As illustrated, the chambers formed in. the casing member above and, below the rotary valve member M6 are connected by the pipe l It to the drain pipe I I6 from the drain chamber 96 of the control valve 62.

The power piston valve member 66 comprises the casing member l i6 having a sliding power piston i2@ disposed therein with its pistonv rod i2? extending through the oil gland |24 to a position where it abuts the lever 52 to actuate it under predetermined conditions. The other end of the casing member IIB is connected by the pipe @26 to the outlet port of the auxiliary control valve 6i. As there is some leakage of the oil about the piston mem-ber 626, a pipe t28 is provided for draining the lubricant from the power piston valve member 66, the drain pipe IE6 being connected thereto. This drain pipe H28 provides for returning the lubricant from the operating mechanism to the reservoir of the engine I8.

In operation, assuming that the engine i6 is adjusted for operating at a given speed to drive the governor i2, and assuming that the eld rheostat 34 and the carbon pile resistor 32 have been adjusted to so Venergize the field winding iii as to cause the generator i4 to generate a predetermined voltage, the switch 28 is manually operated to close the circuit from the armature winding I6 to the motor 22.

If an excessive load isencountered, such as where a locomotive is pulling a load on a grade, the demand on the generator I4 tends to overload the engine I0 so that a decrease in the speed of the engine Illfrom the speed which it is desired to maintain results. As the speed of the engine I8 decreases, the governor I2 functions to force the lever 86 in a counterclockwise direction to actuate the piston valve member 'I8 of the control valve 62 upwardly against the bias of the spring 98.

As the piston valve 'I2 moves upwardly to clear the outlet port formed by the passage I02, the lubricant is delivered under pressure from the chamber 88 to the auxiliary control valve member i Eid, and since the rotary valve member I 06 Ithereof is actuated in accordance with the speed of the engine, the lubricant is delivered by the auxiliary -valve member 64 to the power piston member 66 in jets, the number and spacing of which depends upon the number of angular positioning or spacing passages II2 that are provided in the rotary valve member I 86 and also the speed of the engine. For a single straight passage II2, as illustrated, in the rotating valve member E66 there will be two passages of the lubricant to the power piston member 66 per revolution of the valve member 64. Likewise, with three passages there will be six admissions of the lubricant to the power piston member 66 per revolution of the valve member 64. On the yother hand, if the ports of a single passage are at right angles or 90? from one another, then only one admission of the lubricant is obtained per revolution of the valve member 64.

As the lubricant is delivered to the power piston member 66, the piston I20 is actuated to operate the lever 52 against the bias of the spring member 58 in intermittent steps to decrease the pressure on the stack of discs 38. The piston IE6 of the power piston member 66 moves in small steps depending on the number or revolutions 0i the engine crankshaft per minute, and it is evident that there will be no swings and no engine hunting or oscillations because the change in the pressure on the stack of discs 38 is in small increments. This change in the pressure on the stack of discs also varies somewhat, depending upon the speed of the engine, for it is evident that the increments of movement of the power piston 20 are a maximum when the engine is operatin/grso as to operate the control valve 62 in such a manner that the passage |02 has a maximum communication with the chamber 80 of the control valve member 62. As the speed of the engine increases so that the governor I2 operates to permit return of the piston valve member I to the position shown in Fig. 1, the outlet port |02 from the control valve member is gradually closed while at the same time, the speed of the rotating valve member |06 is increased to decreasethe amount of lubricant which is permitted to pass through the passage I I2 to the power piston 66.

` As the pressure is decreased on the pile resistor 32, the resistance of the resistor 32 is increased to effect a decrease in the eld current of the exciter 28, and consequently, a decrease in the field current of the generator I4. This decrease in the eld current of the generator I4 eiects a decrease in the 'voltage generated by the generator to relieve the overload condition on the engine I0. As the engine I0 is brought to the desired speed, the governor I2 and the lever 86 function to rclease the pressure on the piston valve member 'l0 of the control valve whereby the valve member l0 returns to the position shown in Fig. l.

If the engine |0 drops below full load, the valve member 'I0 of the control valve drops to a position where the valve 'I2 clears the port connecting with the passage |02 so that the passage |02 then communicates with the chamber I8 to deliver the lubricant from the power piston through the pipe |26 and the rotating valve member |06 of the auxiliary control valve 64 in increments, depending upon the speed of the engine, to the chamber 18 from which it is drained through the opening 98 and passage 92 to the drain chamber 96 of the control valve 62, and thence returned through the pipe ||6 to the reservoir of the engine. Such action functions to permit the spring 58 to apply an intermittent increase of pressure on the pile resistor 32 to decrease its resistance, and consequently increase the excitation of the generator 4 to increase the voltage generated thereby.

The same operation is obtained utilizing the valve illustrated in Fig. 2 of the drawing. In this embodiment the control valve and auxiliary control valve are combined in a single valve member |30 having a casing member |32 and a rotating piston member |34 therein. The piston member |34 carries a control valve |36 disposed intermediate of the closure members |38 and |40, the

closure member |36 forming a rotating valve member having a passage |42, either straight or angular, or, if required, more than one passage therein. The end of the rod |44 of the piston member |34 extends through the oil seal |46 and terminates adjacent the lever (not shown) of the governor to be actuated thereby. The end of the rod |44 also carries a suitable gear |48 disposed to be engaged by a gear drive (not shown) and driven in accordance with the speed of the engine.

cant under pressure to the rotating valve member |38 when the valve |36 is actuated upwardly. As illustrated, the ends of the passage |42 in the rotating valve member are so enlarged or the entire passage may be so large that for all operative positions of the valve |36, the passage |42 rotates and periodically is in alignment with the passage |54. The other passage |56 is disposed to deliver the lubricant as it is passed by the rotating valve to the power piston to intermittently operate the power piston. A drain passage |58 is connected to the chamber |60 formed above the rotating member and in which the spring |6I is positioned for biasing the piston member against the lever of the governor and chambers |62, |64 and |66 for draining the lubricant from the valve member, the passage |56 being connected to the pipe |68 to the reservoir of the governor. The valve member |30 illustrated functions in the same manner as the more complicated control valve 62 and the auxiliary control valve 64 of the, embodiment illustrated in Fig. l, it being noted that as the speed of the engine increases the piston member |34- of the valve member |30 drops to a position where the lubricant is intermittently returned from the power piston member through the passage |56, rotating passage |42, and passage |54 to the chamber |62 above the valve |36 and from thence to the drain passage |50. This simplified valve member gives an efiicient regulation.

By means of the regulating apparatus of this invention, it is apparent that a substantially constant speed is maintained for constant speed engines without overloading the engine regardless of the load demand on the generator driven by the engine. At all times, the power supplied by the generator is substantially constant, the

voltage of the generator varying in accordancev with the change in the current demand while the speed of the engine remains substantially constant. Because of the apparatus employed, any change in the load of the engine effects an immediate change in the excitation of the generator, such change in the excitation being directly proportional to the change in the load conditions, for as explained hereinbefore, the control valve and the auxiliary control valve cooperate to adjust the pressure on the pile rheostat in increments which vary in accordance with the This system is very sensitive, it being found that its operation is independent of the temperature or grade of the lubricant employed in the engine.

Although this invention has been described with reference to a particular embodiment thereof, it is, of course, not to be limited thereto except insofar as is necessitated by the scope of the appended claims.

I claim as my invention:

1. In apparatus of the character described, in combination, a uid pressure cylinder, a source of uid under pressure, and means disposed to control the admission of the uid under pressure to the cylinder comprising a valve housing having an inlet port disposed to be connected to the source of iiuid and an outlet port disposed to be connected to the cylinder, and a continuously rotating valve member mounted for sliding movement in an axial direction in the housing. the valve member having a part operative in one position to prevent the flow of fluid between the inlet and outlet ports, said part being rendered inoperative to prevent such ow upon movement thereof from said one position to second termittently connect the inlet and outlet ports in response to rotation of the' valve member when said first part is in its second position to there by cause intermittent delivery oi the iiuid under pressure to the cylinder.

2. In apparatus of the character described, in-

combination, a fluid pressurel cylinder,- a source of fluid under pressure, and means disposed to control the admission of the fluid under pressure to the cylinder comprising valve housing means having a first port disposed to be connected to the source of fluid pressure and having a second port for delivering iiuid to the cylinder, and a slide valve in the housing means disposed for sliding movement with reference to said ports to selectively either connect or disconnect said ports, and means disposed between the second port and the cylinder for rendering the delivery of fluid to the cylinder intermittent comprising a third portin said housing means incommunicaton with the second port and a fourth port in the housing means in .communication with said cylinder, and a continuously rotating valve in the housing means having an opening therethrough disposed to intermittently connect, through said opening, the third port to the fourth port to effect an intermittent delivery of fluid to the cylinder.

3. In valve apparatus, the combination of a valve housing having inlet and outlet ports, and a continuously rotating valve member mounted for sliding movement in an axial direction in the housing, the valve member having a part operative in one position to prevent the iiow of uid between the inlet and outlet ports, said part when moved to a second position being rendered inoperative to prevent such iiow upon movement thereof from said one position in response to slid ing movement of the valve member, the valve member having a second part disposed between the inlet and outlt ports and having a port therethrough disposed to intermittently connect the inlet and outlet ports in response to rotation of the valve member when said iirst part is in its second position.

4. In a system of control, in combination, a

machine the speed of operation of which is to be controlled, a source of huid pressure, valve means for controlling the speed of said machine. said valve means including a stationary housing and valve members so coupled to a rotating part of said machine to move as a function of the speed of said machine, said housing and valve vmembers each being provided with coacting apertures that are brought into registry upon a predetermined speed change of 'said machine and the time period of registry is inversely proportional to the machine speed and the number of periods being directly proportional to the machine revolutions, and means, responsive to the quantity of fluid owing from said source of iiuid pressure through said valve means, for controlling the operation of said machine. f

5. In a system of control, in combination, a source of fluid pressure, e, hydrostatically balanced valve having a housing provided with an inlet opening and an outlet opening and a valve stem rotatably and slidably disposed in the hous ing, a machine for rotating the valve stem in proportion to the speed of said machine, a governor operated by said machine for shifting the valve stem axially with -changes of speed of the ma chine, said stem having aperture means and a slide valve portion which normally, when the machine speed is at the desired value, block registry between the inlet opening and outlet opening, but upon axial shifting of said valve stem by the governor are caused to register the sectional area of registry being a function of the governor operation and the time period of each registry being a function of the rotation of the valve stern` by said machine, and means, responsive to the quantity of uid flowing through said valve, for controlling the operation of said machine..

6. In apparatus of the character described, in combination, a fluid pressure chamber, a source of duid under pressure, and means for controlling the ow of fluid from the source of fluid pres`1 sure to said chamber, said means comprising valve housing means having a rst port disposed in communication with said source of iiuid pressure and having a second port for delivering fluid to said pressure chamber, a slide valve in the housing means disposed for sliding movement with reference to said ports so as to place said ports in communication as a function of the magnitude, from zero to a given maximum, of the movement of the valve with reference to said ports, saidvalve housing means having a third port in communication with the second port and having a fourth port in communication with the pressure chamber, and a rotatable valve disposed in the valve housing means and provided with an aperture therethrough for placing the third port in communication with the fourth port to provide for the delivery of the fluid to the pressure chamber in intermittent spurts depending on the speed of rotation of the valve.

7. In apparatus of the type described, the combination of, three chambers containing iiuid under three diierent pressures, valve housing means disposed between said chambers, said valve housing meansv having two inlet ports one being in communication with the chamber containing the fluid under the highest pressure and one being in communication with the chamber containing the fluid under intermediate pressure and an outlet port in communication with the chamber containing luid under the lowest pressure, valve means in said valve housing means comprising a rotatable valve element and a slide valve element, said slide valve element having a normal, or neutral, position for blocking intercommuni cation between said chambers but which upon one direction of movement from the neutral position provides a communication between the chamber of highest pressure and intermediate pressure as a function of the magnitude of the movement in the said one direction and which upon a movement in its other direction from the neutral position provides a communication between the chamber of intermediate pressure and theI chamber of lowest pressure as a function of the magnitude of the movement in the said other direction, said rotatable valve elementhaving aper-