US2541643A - Hydraulic governor switch mechanism - Google Patents

Description

Feb. 13, 1951 D. w. DUSINBERRE Erm. 2,541,643

HYDRAULIC GOVERNOR swzTcH uEcHANIsM Filed Nov. '7, 1946 2 Sheets-Sheet l D. w. nuslNBERRE x-:TAL 2,541,643

Feb. 13, 1951 HYDRAULIC GOVERNOR SWITCH uEcHANIsu 2 Sheets-Sheet 2 Filed Nov. 7, 1946 Patented Feb. 13, 1951 HYDRAULIC GOVERNOR SWITCH MECHANISM David W. Dnsinberre. Ridgewood, and

Fred

Brychta, Caldwell, N. J., signora to Curtiss' Wright Corporation, a corporation of Delaware Application November 7, 1946, Serial No. 708,354 4 Claims. (Cl. 20G-80) Ihis invention relates to speed governors and is concerned particularly with improvements in hydraulic governors wherein the sensitive portion of the governor is responsive to hydraulic pressure developed by a rotating impeller driven by an engine or mechanism whose speed is to be governed. Objects of the invention are to provide a unitary, speed responsive hydraulic governor for an engine. to provide a regulatingfsystem for a plurality of engines and governors, to provide an improved mechanism for translating ofispeed responses in a governor to speed corrective impulses in an engine, and to provide an improved !orm of proportional governor wherein the amount of off-speed of the engine determines the extent of speed correction imposed on the engine. Y

'I'he above objects, along with additional objects, will become apparent in reading the annexed detailed description when read in connection with the accompanying drawings. It is to be expressly understood that the drawings are employed for purposes of illustration only and are not designed as a' definition of the limits of the invention, reference being had to the appended claims for this purpose.

In the drawings,

Fig. 1 is a section through one embodiment of the governor of this invention;

Fig. 2 is a section taken on the line 2-2 of Fig. 1; and i Fig. 3 is a section through an alternative form of governor with associated controls and environment.

While the governor of this invention has general utility for single speed controlled engines of any type or for a plurality of speed controlled engines of any type, it is particularly adapted for use with internal combustion engines and propellers as used on aircraft. The term engine used herein is to be considered in its broad s:nse, to include motors, turbines and other mechanisms with which governors are used.

Referring iirst to Figs. 1 and 2, we provide a governor comprising a lower housing element I adapted to be mounted on an engine or on other suitable mounting, the housing -having formed therein, a cylindrical cavity I2 within which is disposed a vaned rotor I4 mounted on a shaft I6 extending through the lower face I6 of the housing forv connection to, and drive by, some portion of the engine whose speed is to be governed. 'I'he cavity I2 is covered by a plate I8 secured to the housing I8 by screws I9, said plate Il having formed therein a passage 22 opening at one end to the center of the impeller I4 and at its other end 23 to a well 24 formed in the housing. The cover I8 is provided with a plurality of holes or ducts 26 formed preferably in a circle substantially at the outer ends of the vanes of the rotor I4. The rotor cavity I2 is fed with hydraulic fluid through the passage 22 in a manner which will be described, and upon rotation of the shaft I5 and the impeller I4, the iluid in the cavity I2 is pressurized by centrifugal force to an extent dependent upon the impeller rotational speed. Any static pressure on the fluid in the passage 22 exists throughout the cavity I2, the ducts 26 and a chamber 28. When the vaned rotor or impeller I4 is rotated, a pressure rise, caused by centrifugal force, will be imparted to the fluid, with or without substantial uid flow, and this pressure rise will be a function of the rotational speed of the impeller. The pressure rise created at the impeller periphery is transmitted to the chamber 28 through the ducts 26 and thus pressure in the chamber is a function of engine speed. The side faces of the impeller, preferably, have small clearance with the bottom of the cavity I2 and with the cover I8, to minimize recirculation within the cavity. The impeller pressure rise would be partially lost if recirculation were permitted by wide clearances in the cavity.

In the housing III and above the cover I8, the chamber 28 is formed, with which the ducts 26 communicate. The chamber is closed by a diaphragm 30 secured at its edges to the housing and secured in its central portion to a member 32 capable of movement toward and away from the housing I0. The chamber 28 is normally full of hydraulic fluid and with increases in the fluid pressure, movement of the member 32 will be urged in an outward direction. Such movement is resistzd by a spring 34, commonly called a speeder spring in the propeller governor art, the

force exerted by said spring being adjustable by means of a movable abutment 36 slidable in an upper housing 38 and movable in an axial direction by a pinion and rack connection 40. Rotation of the pinion 40 is afforded by the control lever 42. The upper housing 38 is secured to the lower housing I0 by screws 44.

The spring 34 may be set by the lever 42 to exert force on the member 32 corresponding to a certain desired R. P. M. setting for the engine. If the rotational speed of the impeller I4 is less than the speed corresponding to the desired engine speed, fluid pressure in the chamber 28 will be less than that necessary to balance the spring 3 34, whereby the member 32 may move downwardly. If the impeller rotational speed is higher than that corresponding to the desired engine speed, pressure in the chamber 28 will be greater than that necessary to balance the spring 34 and the member 32 will move upwardly. Mechanism is provided.vas will be described, to translate movements of the member 32 into control effects upon the engine to increase or diminish its speed until proper balance between the spring 34 and the pressure in the chamber 23 is 4obtained, resulting in an on-speed condition of the engine.

Within the well 24, a face cam 43 is disposed, said cam including a hollow shaft 60 borne at its ends in the lower housing I and ina bearing plate 32 secured to the lower housing l0. 'Ihe by a spring 62 into engagement with the cam 48.: The upper end of the' cam' follower 60 protrudes through the plate'32 and carries a .pivot 64 to which a transverse beam 66 is, articulated. The other end of the beam 68 is articulatedto the member 32 by a pin and slot connection 68. Between the ends of the beam 66, upper and lower electrical contact points 68 and` 10 are secured in insulated relation tothe beam, and a flexible connector 12 connects the contact points 69 and with a pin 14 on a connector plug 16 secured in the upper housing 33. A lower contact point 18 is secured to the plate I2 in insulated relation and is connected to a pin 30 on the connector plug 16 by a wire 32. An upper contact 34, carried in insulated relation by a bridge element 86 secured tothe plate 52, is connected t0 a pin 38 in the connector plug 18 through a wire 90. When the governor is in operation, the cam follower 60l will continually rise and fall by the action of the cam 48 which will continually cause up and down movement of the right-hand end of the beam 66. When the member 32 is in a central, on-speed condition, the left end of the beam 66 will not move and the spacing of tbe contact points will be so arranged that as the points 69 and 10 move with the beam they will not touch the points 34 and 18. However, if an oil-speed error exists, the member 32 will rise y or fall, causing corresponding movement of the pivot 68, whereupon, with a small off-speed condition, a succession of contacts will be established between the points 69 and 34 or alternatively between the points 10 and 13. If the oil-speed condition is severe, the member 32 will have moved from its neutral position a considerable amount causing longer contact dwells of the `several points and if the off-speed is even more severe, regardless of the up and down movement of the cam follower 60, continuous switch point contacts will be obtained until speed corrections enable interrupted contacts and eventually no contacts. If continuous or long dwell switch point contacts occur, the member 32 will yield during up and down movement of the cam follower, since the beam 66 will swing about thel engaged switch points as a fulcrum. Since the pressure exerted either by the centrifugally caused fluid pressure in the chamber 23 or by the spring 34 is elastic,-

the member 32 may yield without affecting the restoring eifect either of the fluid pressure or of the spring, but' will continue -to exert pressure until an off-speed error is corrected and Vuntil the several contact points move relatively without contacting one another.

The several pins 14, 30 and 88 in the plug 16 are connected to a speed control system which will be more fully explained in connection with Fig. 3.

In order to provide lubrication for the mechanism in the well 24, and to supply fluid for the impeller |4`and chamber 28, a fluid supply passage 94 carrying oil or fluid yleads from the mounting face |6 of the governor to the well 24, and a needle valve 96 is provided in the passage to regulate theV `amount of fluid feed. Ordinarily. the amount of fluid needed is quite small. The passage 94 is intended tobe supplied with fluid from an appropriate supply passage on the governor mounting pad on the engine or mechanism which will coact with the end of the passage 94. Fluid flowing through the passage 94 nils the well 24 and overilow passes through openings 98 in the hollow cam carrying shaft 50 whence the iluidpasses through a passage |00 in the housing |0 and thence through ports |02 through the 'hollow of the shaft I6 to dump into the engine or mechanism upon which the governor is mounted. 'Ihe well 24 acts as a reservoir, making fluid available to the opening 23 of the passage 22 and thence to the impeller cavity. If an overs'peed condition occurs the impeller I4 will pump iluid into the chamber 28 and the diaphragm 30 and its member 32 will rise increasingthe volumetric capacity of the system. Fluid make-up for this occurrence is obtained from the well 24.`` If an underspeed condition exists in the governor,

the member 32 will reduce the volumetric capacity of the chamber 28v and the impeller cavity and some of the fluid in the system will back up and be returned to the well 24 for overflow through the holes 98 and the passage |00. The feed of fluid through the passage 94 and past the valve 86 will be adjusted to meet all expected underspeed and overspeed conditions so that the well 24 will at all times contain a suillcient amount of fluid.

Referring now to Fig. 3, the lower and right hand parts of the governor assembly are substantially the same as the corresponding portions of the embodiment of Fig. 1 and similar parts bear the same reference characters. In Fig. 3, we show schematically, a power plant or engine or other device whose speed is to be controlled,

at |06, such engine being provided with a governor drive connection |08 eiectlve to rotate the governor shaft I5. The engine as shown drives a controllable pitch propeller |`|0 having a. conventional reversible electric pitch changing motor ||2 which serves when energized to alter the pitch of propeller blades i i4 for greater or lesser angle of attack. Power to drive the electric motor H2 is provided by a power source IIB and the propeller carries slip rings I8, three being shown,

electrical system is susceptible of considerable desired speed control of an engine or speed controllable mechanism.

In Fig. 3, we provide a hydro-pneumatic speed control system in le`u of the speeder spring arrangement of Fig. l. This system comprises a header tank |38 having fluid therein and having an air or gas space or bell |32. The fluid and gas is placed under pressure by a manually operable pump |34, such as a plunger pump, which is adjustable by a handle |35 either directly as shown or through indirect or servo mechanisms. The pressure in the tank may be read on a gage |38 which if desired may be calibrated directly in R.. P. M., rather than pressure, so that the handle |36 may be adjusted directly to secure a desired R. P. M. The preset pressure in the tank |38 is then transmitted through a pipe |48 to a chamber |42 formed by an upper housing |44 secured to the lower governor housing I8 through an' adapter |45. The chamber |42 is formed in part by a diaphragm |46 with an associated movable member |48 secured to or integral with the movable member here designated as 32'. The fluid under pressure in the chamber |42 is equivalent in effect to a spring since the pressurized gas or air at |32 in the tank |38 provides elastic means to permit the member 32' to move up and down in response to speed errors and to nally reach equilibrium when the fluid pressure in the chamber |42 and that in the chamber 28 is equal. The space between the diaphragms 38 and |46 may be vented to atmosphere since the pressure between the diaphragms has no effect on the operation of the system. Alternatively, bellows, resilient sleeves or pistons could be used in lieu of the diaphragms.

The tank |38 may be used as a controllable elastic pressure source for a. plurality of engines vand governor assemblies, and pipes |52, |54 and |56 leading from the tank |38 are extendedto similar governor units applied to serve additional engines or power controlling a plurality of governors, the single pressure tank |38 and the single tank pressure controller |36 serve to adjust all governors simultaneously in order that speed synchronism between several engines may be maintained.

We further show a tankV |68 connected by a pipe |62 to the impeller intake cavity 22 of the governor to supply hydraulic iluid tothe impeller. Pipes |63 similar to |62 lmay lead from the central supply to other governors of a multiple system.

This tank |68 furnishes fluid to the governor irnpellers |4 in lieu of fluid supply from the well 24 of each governoix However, each governor may be arranged as in Fig. 1 with iluid supply for the impeller |4 leading from the well 24.

In the hydraulic speed control system exemplified by Fig. 3, utilizing an impeller supply tank such as |68, the tank may be held under a controlled positive absolute pressure so that the entire system is independent of altitude or atmospheric pressure.

The electrical contactor systems disclosed merely exemplify one means for ataining speed control of engines or other mechanisms. The speed control may be accomplished mechanically, hydraulically, or by oher electrical means without departing from the spirit or scope of the invention. Likewise, no limitation on the scope of the invention is to be implied by the showing of the electrically operated controllable pitch propeller as a means for speed control on an engine or mechanism-other iorms of control such as fuel or energy input control or other means' of load control are considered as being wholly within the scope of the invention.

Though but two embodiments illustrating the invention have been shown and described, it is to be understood that the invention maybe apy plied in other and various forms. -Changes may plants. Thus, when used for ltrol element cooperable at times be made in the arrangements, without departing from the spirit of the invention. Reference should be had to the appended claims for deilnitions of the limits of the invention.

What is claimed is: Y

l. A hydraulic speed governor comprising a driven rotor having varies, a housing within which said rotor is contained having a duct for feeding hydraulic uid to the rotor center and a duct for passing fluid at the rotor periphery, a chamber fed by the last` said duct, a movable member in said chamber, movable under the iniluence of uid pressure changes caused by variation in the rotational speed of said rotor, adjustable resilient means acting on said movable member forr counteracting the uid pressure acting thereon, and means operated by and sensitive to movements of said movable member to ad- Ajust the speed of said rotor, said adjusting means comprising a xed electrical contactor assembly having spaced speed increasing and'decreasing contacts, a contact movable with and with respect to said movable member to engage at times either of said spaced contacts, and means operated by and at a speed proportional to that of said rotor to move said movable contact cyclically toward and away from said spaced speed increasing and decreasing contacts 'and with respect to said movable member, movements of said movable member causing contacts of said movable contact with one or the other of said spaced contacts, at times, only when both said members movements are in the same direction.

2. In a switch adapted for use with a speed governor, a member movable in response to speed deviations from a set value, a reciprocable member movable at a substantially uniform frequency and through a substantially fixed range in a direction substantially parallel to the direction of movement of said first member, a, beam connecting said members, movable therewith, having a speed control element thereon, and a fixed conwith and upon movement of said beam-carried element only when said first member is displaced from a neutral on-speed position.

3. 'In a switch adapted for use with a speed governor, a member having a neutral on-speed position and movable therefrom with oil-speed conditions, a member movable over a substantially xed range and at substantially fixed i'requency and in a direction substantially parallel to the direction of movement of said rst member, means connecting said members, movable therewith, and carrying a speed control element, and a substantially xed speed control element with which said first speed control element engages only when said first member is in an oilspeed position.

4. In a switch for a control system, a member movable along a path according to a controlled effect, a reciprocating member movable in a path substantially parallel to the other path at a substantially uniform frequency and through a substantially fixed range, a beam connecting said members, movable therewith, having a control element fixed thereon intermediate said members, and s. iixed control element contact-- abie at times with and upon movement of said beam carried element, onLv when sai first member is.disple.c.eci from a. certain tion in its range of movement. 5

DAVID W. DUSINBERRE. FRED BRYCHTA.

REFERENCES CITED The following references are of record in the 10 nie of this patent:

UNITED STATES PATENTS Number Name Date 941,409 Ehrhart Nov. 80, 1909 15 Number Number

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