Actuating arrangements for aircraft control surfaces

Claim 2

An actuating arrangement for lift control surfaces on each of a pair of aircraft wings, comprising drive means, a control apparatus, responsive to electrical control signals, for the drive means, first and second transmissions between the drive means and first and second control surfaces on the respective wings, first and second generating means coacting with the first and second transmissions respectively to provide first electrical signals respectively dependent on the driven positions of the said transmissions, third and fourth generating means coacting with the first and second transmissions respectively and responsive to said first electrical signals from said second and first generating means respectively to provide second electrical signals dependent on a difference between the driven positions of the transmissions, and first and second switch means operable in response to said second electrical signals, said control apparatus being responsive to said second electrical signals and being effective to arrest the said transmissions when both said switch means are operated.

Claim 3

An arrangement as claimed in claim 1 in which said first and second generating means comprise synchro generators.

Claim 4

An arrangement as claimed in claim 2 in which said third and fourth generating means comprise synchro differential generators.

Claim 5

An arrangement as claimed in claim 3 in which the rotors of said first and third generating means are driven by an end of the first transmission remote from the drive means, and in which the rotors of said second and fourth generating means are driven by an end of the second transmission remote from the drive means.

Claim 6

An arrangement as claimed in claim 3 in which said switch means includes first and second synchro control transformers having stator windings connected to the respective rotor windings of said third and fourth generating means.

Claim 7

An arrangement as claimed in claim 5 in which said switch means also includes first and second switching devices responsive to substantial variations in output signals from said respective synchro control transformers to de-energise said control apparatus.

Claim 8

An arrangement as claimed in claim 6 in which said first and second switching devices respectively include first and second parallel prirs of contact breakers arranged to be opened in response to said output signal variations from the associated synchro control transformer.

Claim 9

An arrangement as claimed in claim 7 in which each of said first and second switching devices includes a warning device and a third contact breaker which is closed to energise said warning device in response to said output signal variations from the associated synchro control transformer.

Claim 10

An arrangement as claimed in claim 7 which includes third and fourth pairs of contact breakers, a further drive means, a further control apparatus for the drive means, third and fourth transmissions between said further drive means and third and fourth control surfaces on the respective wings, fifth and sixth generating means coacting with the third and fourth transmissions respectively to provide third electrical signals respectively dependent on the driven positions of said third and fourth transmissions, seventh and eighth generating means coacting with the third and fourth transmissions respectively and responsive to said third electrical signals from said sixth and fifth generating means respectively to provide fourth electrical signals dependent on the difference between the driven positions of said third and fourth transmissions, further switch means which includes fifth and sixth parallel pairs of contact breakers, said fifth and sixth pairs being respectively in series with said first and third pairs of contact breakers, seventh and eighth parallel pairs of contact breakers forming part of said further switch means and respectively in series with said second and fourth pairs of contact breakers, the arrangement being such that operation of either switch means to open its associated contact breakers can de-energise both control apparatuses.

Claim 11

An arrangement as claimed in claim 9 which includes first and second by-pass switches respectively in parallel with said fifth and eight contact breaker pairs, so that when said by-pass switches are closed operation of said further switch means to open said fifth, sixth, seventh and eighth contact breaker pairs does not de-energise the first-mention control apparatus.

Claim 12

An actuating arrangement for lift control surfaces on each of a pair of aircraft wings, comprising first and second drive means, first and second control apparatus, responsive to electrical control signals, for said first and second drive means respectively, first and second transmissions for connecting said first drive means to first and second control surfaces on the respective wings, third and fourth transmissions for connecting said second drive means to third and fourth control surfaces on the respective wings, first and second generating means co-acting with the first and second transmissions respectively to provide first electrical signals respectively dependent on the driven positions of said first and second transmissions, third and fourth generating means co-acting with said first and second transmissions respectively and responsive to said first electrical signals from said second and first generating means respectively to provide second electrical signals dependent on a difference between the driven positions of said first and second transmissions, first and second switch means operable in response to said second electrical signals, fifth and sixth generating means co-acting with the third and fourth transmissions respectively to provide third electrical signals respectively dependent on the driven positions of said third and fourth transmissions, seventh and eighth generating means co-acting with the third and fourth transmissions respectively and responsive to said third electrical signals from said sixth and fifth generating means respectively to provide fourth electrical signals dependent on a difference between the driven positions of said third and fourth transmissions, and third and fourth switch means operable in response to said fourth electrical signals, said first and second control apparatus being responsive to operation of said second and fourth electrical signals and being effective to arrest said transmissions when either said first and second or said third and fourth switch means are operated.

Claim 13

An actuating arrangement for lift control surfaces on each of a pair of aircraft wings, comprising first and second drive means, first and second control apparatus, responsive to electrical control signals, for said first and second drive means respectively, first and second transmissions for connecting said first drive means to first and second control surfaces on the respective wings, third and fourth transmissions for connecting said second drive means to third and fourth control surfaces on the respective wings, first and second generating means co-acting with the first and second transmissions respectively to provide first electrical signals respectively dependent on the driven positions of said first and second transmissions, third and fourth generating means co-acting with said first and second transmissions respectively and responsive to said first electrical signals from said second and first generating means respectively to provide second electrical signals dependent on a difference between the driven positions of said first and second transmissions, first and second switch means operable in response to said second electrical signals, fifth and sixth generating means co-acting with the third and fourth transmissions respectively to provide third electrical signals respectively dependent on the driven positions of said third and fourth transmissions, seventh and eighth generating means co-acting with the third and fourth transmissions respectively and responsive to said third electrical signals from said sixth and fifth generating means respectively to provide fourth electrical signals dependent on a difference between the driven positions of said third and fourth transmissions, and third and fourth switch means operable in response to said fourth electrical signals, said first and second control apparatus being responsive to operation of said second and fourth electrical signals and being effective to arrest said transmissions when either said first and second or said third and fourth switch means are operated.