AU441925B2 - Hydraulic coupling - Google Patents

Description

14 88 917' This invention relates to a hydraulic coupling

device which may be installed in the transmission line of an

hydraulic system to transmit a signal from one point to an-

other for remote control or actuation of a controlled

apparatus. The hydraulic fluid is not transmitted from one

point to another, but when a pressure is exerted upon the

fluid at the control unit, pressure is exerted on the remote

apparatus since the pressure is transmitted through the fluid. Such hydraulic systems can be used in a large

variety of applications and have been found to. be particular-

ly useful for controlling the hydraulic locking devices in

airplane seats, as disclosed in our U.S. Patent specification

No. 3,173,263 for example. The hydraulic locking device releasably holds the

backrest at any selected angle of inclination: it comprises

a cylinder and a piston which divides the cylinder into two

hydraulic locking chambers. A normally closed locking valve

control flows between the two locking chambers. When the

control unit push button is actuated, a signal is transmitted

to the remote apparatus, opening the locking valve and allow-

ing fluid to flow between the two locking chambers in the

cylinder.

Installation and maintenance of such hydraulic

systems in airplane seats is often difficult due to the limi-

ted space available and also due to the fact that the

hydraulic line from the control unit must be snaked through

the arm of the seat structure for connection to the hydraulic

locking device. During installation and repair, the hydraulic

fl:lid must be injected into or removed from many of such

systes after the structur.l components have been put -into -2 441.9 2 place. Any hydraulic fl 8 8during ,1il4 ost 91M7 these operations is not only wasteful but also potentially damaging to the surrounding equipment. The present invention provides a coupling device for use in the hydraulic line between the control unit and the remote apparatus. According to the present invention there is pro- vided a hydraulic coupling deviice comprising first and second parts releasably held together, each part comprising a com- partment connected to a fluid line and closed by means which are movable to permit the volume of the compartmient to change, the said means of the two parts being in abutment, .whereby movement of one mean's causes the other means to move.

The coupling device senses an increase in pressure at the control unit and mechanically transmits a force through the coupling device in response'to it. The mechani- cally transmitted force is then retranslated into an hydraulic pressure which is transmitted to the remote apparatus. The two movable means can be pistons which are in abutment for the mechanical force transmittal when the coupling parts are together. The coupling parts can be held together by a spring clip which can easily be released so as to open the coupling. The invention allows an hydraulic line to be broken at an intermediate point between a control unit and a remote apparatus without loss of hydraulic fluid or any pre-pressurization which may have been manufactured into the system. Installation of thbe device is simplified in that less

difficulty is encountered in snaking the hydraulic line throug4 a seat structure, fo r example. Installation and maintenantce

441.925 are both simplified in tha parT's can be installed and removed with the fluid in the hydraulic system, obviating the danger of leakage or loss. An added advantage of the invention is that, when repair is necessary, less time and labour are required for removal of only those structural elements which must be re- paired, since the amount of disassembly is greatly diminished. The invention will be described in more detail, by way of example, with reference to the accompanying draw- ings, in which:- Figure 1 is a sectional view of an hydraulic coup- ling embodying the invention, illustrating thecoupling as positioned within a remote control system; Figure 2 is a like view of the coupling in a second operating position; Figure 3 is a sectional view of the coupling when uncoupled; Figures 4 and 5 illustrate, in the closed and opened positions respectively, the catch which holds the parts of the coupling together, as viewed along line IV-IV of Figure 2. Figure 1 shows a control unit 11 which, when actuated, transmits a control signal to a remote apparatus 13. The control unit 11 and the remote apparatus 13 are completely described in the aforesaid Patent specification. In general, however, the control unit11 comprises an operator actuated knob 15 fo; shifting.a piston 17 within a cylinder 19 against a confined hydraulic fluid and a spring 21 within a chamber 23. The pressure of the fluid in chamber 23 is transmitted, via a line 25, a coupling 27, and a line 29 to a chamber 31

1488 9170 in the remote operating unit 13. The increase in pressure rigid in chamber 31 serves to actuate a diaphragm 33 and a

metal disc 35, against the force of one or more Bellville to springs 37, to motivate an operating rod 39 which acts

open a normally closed locking valve in an hydraulic locking

device (not shown). Now, with reference to Figures 1-3, the coupling fits 27 is seen to comprise a male coupling part 51 which

within a female coupling part 53. The male part 51 comprises

a first portion 55 which fits within a second portion 57, a A diaphragm 59 being firmly, fixed between the two portions. the fluid chamber or. compartment 61, formed on one side of

diaphragm 59, and which may be filled by means of an opening

which is normally sealed by a screw 63, is in communication

with the transmission line 29. A plunger 65 is slidably

mounted in a compartment 66 within the portion 55 such that

it is in contact with the diaphragm 59 on the side thereof

opposite the fluid chamber 61; it is provided with a cir-

cumferential groove 67 which carries an 0-ring 69. As shown

in Figures 1 and 5, the 0-ring 69 cooperates with a shoulder

71 of the portion 55 so as t o maintain plunger 65 therein

when the coupling is open, as shown in Figure 3. Use of the 0-ring on plunger 65 makes ceseubly easy.

'.,hen the coupling part 51 is assembled initially, the plunger

is not installed within the compartment 66. The coupling is part is attached to the apparatus 13 via line 29 and fluid

placed in the compartment 61, line 29, and ccmpartient 31 by

means of the opening normally sealed by the screw 63. The

0-ring 69 is then placed within the groove 67 and the plunger is forced into the compartment, deforming the u-r.i.n until it

441.925 he 711?4. 88 91M passes teshould .71 necessary the open end of the compartment may be chamfLered to facilitate the initial de- formation of the ring. After the ring 69 has passed the shoulder 71, it resumes its normal shape and serves as a retainer to hold the plunger in the compartment against the pressure it has now created in the chambers 31 and 61 and the line 29. Although both coupling parts could be manufactured in this way, another form has been shown for the part 53 to illustrate an alternative embodiment of the invention. The female part 53 of the coupling has a first portion 75 inserted within a second portion 77, and a flexible diaphragm 79 is firmly fastened therebetween. A fill screw 81 In the section .77 serves to seal an opening and can be removed to allow fluid to be placed within a fluid compart- ment 83 which is in communication with the hydraulic line A plunger 85 is mounted in a compartment 86 on the side of the diaphragm 79 opposite the fluid compartment 83, and, as shown in Figures 1 and 2, it extends through an internal flange 87 in the portion 75 to abut the plunger of the part 51. A shoulder 89 on the plunger 85 cooperates- with the internal flange 87 to maintain the plunger 85 within the coupling portion 53. If, %,hen the members 51 and 53 are uncoupled, it is desired to maintain -the pressure in the line at the level normally carried therein when the actuator button 15 is not actuated, a spring 91 is positioned between- the flange '87 and the shoulder 89 so as to maintain the relative position of the parts sho-im in Figures 1 and 3. In opcration, when the button 15 is actuated, pressure is exerted within compartment 23, line 25, and 6- 441.925

14 889 I7 compartment 83, causing the aiaphragm 79 and plunger 85 to

move to the left from the position shown in Figure 1 -o that shown in Figure 2. The movement of plunger 85 causes,a

similar movement of the plunger 65 so that the diap .agm 59

exerts a pressure on the fluid and compartment 61, line 29,

and compartment 31, causing the diaphragm 33, plate- 35 and rod 39 to move to the right from the position shown in Figure

1. When the button 15 is released, the structure retumrs to

the respective positions illustrated in Figure 1 If it is desired to ensure that no .force is trans-

mitted from the remote apparatus 13 to the control unit 11

which could damage it the plunger 65 can be of such diameter

that it contacts the internal flange.87, as shown in Figure

1, and is thus restrained from forcing the.piston 85 to the

right, as shown in the drawings. Although the coupling parts 51 and 53 can be held

together by any suitable means, it is preferable that the

structure utilized be quickly and easily attached and

removed. For this reason, a releasable catch has been

illustrated to interlock the two telescoping coupling members

51 and 53 with a snap action when the portions are moved together.

Referring to Figure 4, a wire spring 101 having two

arms 103 straddles the female part 75 for releasable engage-

ment with a circumferential groove 105 in the portion 55 of

the male part 51. The two arms 103 of the spring extend

into two partially circumferential slots 107 in the coupling

part 53. The arms are connected by a central, outwardly

bowed section 109 which, when depressed, allows the spring

to be shifted from the position shown in Figure 4 to that 44L925

1 88 9/ shown in Figure 5. Retenton of te spring on the coupling is provided for by a peripheral recess 111 in which hook- ends 113 of the arms 103 are inserted when the. spring is positioned on the coupling. When a radially inwards force is exerted on the section 109 of the spring, the portions 115 of the arms 103 are forced radially outwardly by cam sections 117 in the slots 107. This causes the spring to be removed from the groove 105 and the coupling parts can then be separated. When the coupling is reassembled, the portions are merely mated and the hooked sections 113 of the spring are pushed back to the position shown in Figure 4.

8 441.925

Claims (1)

1. "14889p The claims defining the invention are as follows:-

   1. A hydraulic coupling device comprising first

   and second parts relea.ably held together, each-part compris-

   ing a compartment connected to a fluid line and closed by

   means which are movable to permit the volume of the compart-

   ment to change, the said means of the two parts being in abutment, whereby movement of one means causes the other

   means to move.

   2. A device according to claim 1, wherein the

   said movable means comprise first and second pistons slidable

   in the first and second parts respectively. 3. A device according to claim 2, wherein each

   said compartment is sealed by- a flexible diaphragm against

   which the corresponding piston acts.

   4. A device according to claim 1, 2 or 3,

   wherein at least one of the parts comprises retaining means

   for retaining the said movable means therein and therefore

   setting a limit to expansion of the volume of its compartment.

   A device according to both claim 2 and claim

   4, wherein the second piston is surrounded by a resilient

   O-ring arranged to cooperate with a shoulder of the second

   part to act as a retaining means for the second piston. 6. A device according to any of claims 1 to

   wherein the first part has a stop member against which-, when

   the parts are together, the movable means of the second part

   can abut to limit movement of the same.

   7. A device acco±rdimg to both claim 2 and claim

   wherein the first and second pistons are respectively of

   smaller and larger area, the said stop tember being constitu-

   ted by the portiont of the first part through which the first

   9 -441.92 A piston protrudes to act ag l e nd piston. 8. A device according to any of claims 1 to 7, wherein the movable means of the first part is biased in the direction away from the second part.

   A device according to claim 8, wherein the movable raeans of the first part is biased by a compression

   spring acting between the movable means and a stop member

   of the first part. A device according to any of claims 1 to 9, wherein the parts are releasably held together by a spring

   clip received in grooves in one part and ergaging through

   these grooves in a :groove in the other part, and from which

   groove the climp can be withdrawn to release the two parts.

   11. A device according to claim 10, wherein the first said grooves and the spring clip are so shaped that a sliding movement of the clip cams the clip out of the groove

   in the other part. 12. A hydraulic coupling device substantially as described with reference to and as shown in the accompany-

   ing draviings.

   DATED this SIXTEENTH day of AUGUST, 1973

   P. L. PORTER CO.

   Patent Attorneys for the Applicant SP!-USON FERGUSON

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