US2373745A - Hydraulic telecontrol device - Google Patents

Description

April 17, 1945. CONWAY 2,373,745

- HYDRAULIC TELE-CONTROL DEVICE Filed March so, 1942 25heets-Sheet L1 H. G; CONWAY HYDRAULIC TELE-CONTROL DEVICE April 17, 1945.

Filed March 50, 1 942 2 Sheets-Sheet 2 Patented Apr. 17, 1 945 UNITE-D STATES PATENT OFFICE HYDRAULIC rmLEcoN'raoL nnvrcn Hugh Graham Conway, Warrlngton, England, as- T signor to Aeronautical & Mechanical Invest- -ments Limited, a British company Application March30, 1942, Serial No. 436,909

In Great Britain April 2, 1941 This invention comprises improvements in or relating to hydraulic tele-control devices.

- A type of.hydraulic tele-control apparatus is known in which a transmitting station comprises two cylinders and pistons connected respectively to two pipe lines and a receiving station comprises two other cylinders and pistons into which the pipe hnes deliver so that the receiving pair of pistons are forced to copy the movements of the transmitting pair. The pistons being connected by appropriate links to levers mounted on the transmitting and receivingapparatus, movement of the lever at the transmitting end will be copied by the-movement of the lever at the receiving end a of the apparatus.

' In apparatus of the kind described it is only ing to this invention the system comprises three transmission pipes and three compression depossible to transmit motion in one phase, that is to say, a to-and-fro motion, but in many'case'sin' aircraft, members are mounted so asto have a universal movement-about a centre and thus to be capable of a. compound movement. In other .cases .there may be instances where it is desirable to transmit desired movements to or from more than'one control member. To enable such cases tobe met the present invention contemplates whatmay be described as a polyphase hydraulic trans g n.

The present invention tele-controlsystem the combination of three or more transmission pipes connected at one end of comprises in a hydraulic the system to a transmitting (or receiving) station having compression devices and a sing'lea-ctuating member with a compound freedom of movement operatively connected to the compression devices so that the phases of'movement .oi the actuating member correspond to phases of liquid movement in the pipes, said pipes being connected at the other end to a receiving station (or transmitting station. if the first-mentioned end '01. the system is the receiving end) said station having compression devices and one or more actuating members linked to the compression devices so that their phases of movement are compelled to correspond to the phases of movement of the actuating. member at the other station.

It is to be understood that the expressions one end of the system and the other end of the system are to be taken broadly as meaning the operative ends of the system for the purpose of the tele-control under consideration. There may 'be branches in such a system or the pipes may run beyond thefen {for purposes special to a particular installation. For example, it is kmwn that a single phase system may have two or more transmitting stations and it would be within the "Pi s;

vices at the first-mentioned transmitting (or receiving) station and the actuating'member con- 4 sists of a lever pivoted in the centre of the three compression devices so as to have a universal movement about said centre.

- Further features of the invention will appear from the following description, which is given by way of example, of specific embodiments of apparatus in accordance with the invention.v

1n the drawings- Figure 1 is a diagram of one form of apparatus in accordance with the invention showing a transmitting and receiving station and interconnecting Figure 2 is a vertical section through a transmitting apparatus taken on the line 2-2 of Figure 3; I I

Figure 3 is a plan of the same;

Figure 4 is a diagram of one possible alternative system; and.

Figure 5 is a diagrammatic view ternative system.

Referring to Figure 1, I I is a transmitting station and I2 a receiving station of a hydraulic tele-control apparatusin which the transmitting station is provided with three cylinders 13, I4, I 5

grouped equidistantly around a central, pivot l6. Upon the pivot l6 there is mounted for universal movement an actuating lever l'l having a handle l8 and, near the pivot, three radial arms I9, 20,2!

which are connected by piston rods 22 to pistons working in the cylinders l3, l4, 15. The cylinders are connected by transmission pipes 23, 24, 25 to the receiving station l2. At the receiving station I2 are three cylinders 26, 21, 28 containing-pistons which are connected by connecting rods 29 to the three arms 30, ll, .32 of an actuating lever pivotedabout aL-central universal pivot 33 and provided with an upstanding arm-'34 for actuating devices which it is intended to control. Movement of the actuating lever tlin one plane, say thatindicated by the double-headed arrow 35 at of another .al-'

the transmitting station, will cause hydraulic-fluid ,liquid into the cylinder '26 and to cause as much lifting of the lever arm 3| as at the transmitting station there was depression of the lever arm ll. The cylinder 26 being disposed on the opposite in the cylinder II to be expelled or drawn in, ac-

' work over a pin 01 fixed diametrically across the bore of the cylinder II, M or II as the casemay be. This prevents the piston from rotating. Furthermore, on either side of the slot the pistons have flats as shown at 44, Cl and the flatsspan ports 1| in the sides or the cylinders. The ports are covered with filter-gauze II which is exposed t the reservoir 4| and through the filter-gauze hydraulic fluid from the reservoir. can enter the side of the pivot 33 from that which the lever arm It occupies with respect to the pivot It the result.

is that the arm 34 of the lever at the receiving station moves over in an are having the same direction of movement as the leverl1 and to the same extent. Movement in another plane, such as is indicated by the arrow 36, will corresponding'ly produce movement in the same plane by the lever 34 as shown by the arrow 31. and, in fact, movement in any intermediate planes will similarly be copied precisely,.,both in direction and extent.

I It will, of course, be clear that the apparatus as illustrated in Figure 1 is diagrammatic and that all the ordinary means of compensation for leakage, for variation of temperature'and so forth which may becalled for in apparatus of this kind should be provided.

The transmitting and receiving stations-are similar to one another except that the actuatin! lever I! at the transmitting station is provided with a handle and the corresponding lever-i4 at the receiving station is provided with means such as a ball joint 38 'to' enable it to be connected to" any member which it is intended to control. The detailed views shown in Figures 2 and 3 of the transmitting station will therefore serve as a receiving station also.

ports in and thence pass into the space within the cylinders which is provided by the flats '2, '9. From here the hydraulic fluid has access through passages", 13 to a light lift valve 14 mounted in th ends of each of the pistons 83 and held on its seating by a light spring 15. The effect is that if, through leakage or fall in temperature, a reduction takes place in the amount of fluid in the pipes 22, 24, 25 the fluid is made up from the reservoir 4|, and it is impossible for the fluid pressure in any of the pipes to fall appreciably below atmospheric pressure so that entry of air through any leaks, which would spoil theoperation is obviated.

In the apparatus described in Figures 1 to 8 the lever at the receiving end precisely copies the movement of the lever at the transmitting end. It is not, however, essential that this should be the case because it is possible, seeingthat one of the'levers has a compound movement, for the movement at the other end of the system to be provided by two separate levers, one ofwhich copies movements or the lever at the other end in one phase or plane and theother of which levers copies movements of the lever at the other end in another phase or plane.

Referring to Figure '4, this shows atransmitting station comprising cylinders ll, l4, II and a I lever l'l similar to the correspondingly numbered In Figures 2 and 3, 40 represents a casing which I containsan internal space 4| acting as a liquidre'servoir and provided with afllling cap 42. In the casing are secured three cylinder bodies l3,

' I4, li which correspond to the cylinders of Figure 1' and are connected by appropriate union joints to pipes 23, 24, 25, The cylinder bodies parts already described and similarly connected to transmission pipes 23, 24, 24. s 7

At the other end of the system the pipe 23 is connected to a cylinder 80 and the pipe 25 to a have flanges 43 about the middle of their length which abut on the underside of the casing 40 and are clamped thereto by means of a clamping plate 44 secured in place by a central setscrew' 45.

' Packing rings 46, 41 surround the joints which are made between the outsides of the cylinder walls and the casing 40 so that no leakage may take place from the reservoir-4|. The casing is provided with fixing lugs 48, 49, so that it may be secured in a suitable position, for example,

close to the pilot's seat in an aircraft.

On top of the casing 40 there is a'central upstanding forked lug' 5| in which is pivoted at 52' thecruciform central member 52 of a Hookes 62 to pistons 63 one of which is shown in section in Figure 2. The pistons 63 are long cylindrical elements provided with packing rings 84, 65. In

' the central portion they are pierced transversely with along slot 68 which serves to receive and to i cylinder 8 l The cylinder 44 forms one of a pair, each of which contains a piston connected by a link 82 to the opposite ends of a lever having an arm 84 for connection to device. Similarly, the cylinder ll forms one of apair connected by links 82 to a lever having an arm 46. The other-cylinders of these two pairs, which are numbered 81', in the drawings are connected to ether and to the line 24. The effect is that if the lever ll be rocked about a line which passes through its pivot and its connection to the piston in the cylinder l3, the piston-will remain at rest while the pistons inthe cylinders l4 and IE will one of them be moved in and the other one out. This will cause movement of the lever 84 at the receiving station while the leverjtremains at rest. Alternatively, if the lever II is rocked about an axis which passes through theiconnection to the piston in the cylinder II then the piston in the cylinder l3 will be moved in conjunction with that, of l4 and the lever '4 will be moved while 86 remains at rest.- Therefore the-lever H can be used to control, two levers at the receiving station;

Alternatively, there-might be'two levers, such as 84, 86 atthe transmitting station which between them control a single lever such as I! at a receiving station. -In this case. it is assumed that the'lever '84 is held at rest or locked when the lever 86 is operated, and the lever 25 is held or locked when lever 84 is operated.

Moreover, instead of a threerphase system as described, it is possible, as shown in Flgur 5, to have at the transmitter fourc'ylinderl ","ll.

common return line 99. The other cylinders 90 and BI are connected respectively to the two lines 81 and 98. The lines 01, 98, and 89 are connected to a receiver of similar construction comprising four cylinders I00, IOI, I02, and I03 con-, nected to a lever 104. Lines 91 and 88 are con- .nected to cylinders I and I03 respectivelyand the cylinders IM and I02 to the common lin 99. Again. there might be flve or, more cylinders, but the simplest embodiment of the invention would appear to be that which is illustrated in Figures 1 to 3. I

In the following claims, the expression a station" includes a transmitting station or a receiving station, thus in the case where there are two stations the first station may be a transmitting station and the second station may be a receiving station or vice versa.

I claim:

1. In a hydraulic tele-control system, the com bination of a station comprising a member mounted so as to be capable of a compound freedom of movement, three compression devices grouped about the member symmetrically and operatively connected thereto so that movement of the member in any of the directions in which it is free to move produces compression in at least one of the compression devices and corresponding expansion in the remainder, three pipes connected one to each of the compression devices and extending to a second station, three fluidaetuated devices at the second station one in communication with each of the pipes, and a second member at thep'second station pivoted for rocking with a compound-freedom of movement, the fluid-actuated devices at the second station being grouped about said second member symmetrically and operatively connected thereto, whereby movement of the member at one station in any one direction produces corresponding direction of movement of the member at the other station at least one of the members with a compound freedom of movement consisting of a lever mounted on a central pivot element for unision devices consisting of three parallel cylinders the axes of which are grouped about the central v versal movement and, the three fluid-comprespivot element, three' pistons being disposed in the cylinders, and connecting rods connecting the pistons to the lever.

2. In a hydraulic tele-control system, the combination of a station comprising a member mounted so as to be capable of a compound freedom of movement, three compression devices grouped about the member symmetrically and operatively connected thereto so that movement of the member in any of the directions in which it is free to move produces compression in at least one of the compression devices and corresponding expansion in the remainder, three pipes connected one to each of the compression devices and extending to a second station, three fluid-actuated devices at the second station one in com-- munication with each of the pipes, and a second member at the second station pivoted for rocking with a compound freedom of movement, the fluid-actuated devices at the second station being grouped about said second member symmetrically and operatively connected thereto, wherecompound movement without being capable of rotation about an axis extending along the lever, the three'fiuid-compression devices consisting of three parallel cylinders the axes of which are grouped about the Hookes joint, three pistons being disposed in the cylinders, and connecting rods connecting the pistons to the lever.,

3. In a hydraulic tele-control system, the combination of a station comprising a single actuating meinber and a mounting therefor such that the member has a compound freedom of rocking movement, at least three fluid-compression devices grouped symmetrically about the member and operatively connected thereto so that rocking movement of the member in any direction corresponds to compression in at least one of the compression devices and corresponding expantending therefrom to a second station, a second station comprising at least three fluid-actuated devices each in communication with one of said transmission pipes and actuated means operatively connected to the fluid-actuated devices and han one movement positively capable of more controlled by the uid actuated devices.

4. A hydraulic tele-control system as claimed in claim 3, wherein the actuating member consists of a lever mounted on a central pivot element for universal movement and the fluid-compression devices comprise cylinders having axes parallel to one another and grouped about the pivot point, pistons therein, and connecting rods operatively connecting the pistons to the lever.

5. A hydraulic tele-control system as claimed in claim 3, wherein the actuating member consists of a lever pivoted on a Hooke's joint so as to be capable of compound movement without being capable of rotation about an axis extending along the lever, thefluid-compression devices consist of cylinders having axes'parallel to one another and grouped about the Hooke's joint, pistons therein, and connecting rods operatively connecting them with the lever.

6. A hydraulictele-control system as claimed in claim 3, wherein the fluid-actuated devices at the second station consist of cylinders and pis- I necting rods.

by movement of the member at one station in any one directions produces corresponding direc- 7. A hydraulic tele-control system as claimed in claim 3, wherein the fluid-actuated devices at the second station consist of two pairs of cylinders and pistons therein and the actuated means consists of a plurality of levers, one lever located between and operatively connected to thepistons in one pair of fluid-actuated pistons and cylinders and the other lever lbeing located between another pair of cylinders and operatively connected .to the pistons therein so that one lever is operated by movement of the actuating member in one direction and the other lever is operated by movement ofthe actuating member in another direction two of the three pipes respectively connected with one cylinder of each pair and the third pipe connected to both of the remaining cylinders.

HUGH GRAHAM CONWAY.

Images