Torque-sensing devices

Claim 2

Torque-sensing apparatus comprising rotary input drive means, rotary output drive means, a drive member included in at least one of said drive means, a coupling member for drivingly connecting said input and output drive means, a liquid-filled rotary enclosed chamber formed by said coupling member, an end wall of the drive member included in said one drive means and the second drive means, the coupling member being connected to said drive member so that under load conditions said drive member is displaceable relative to said coupling member to vary the volume of said chamber to an extent proportional to the applied torque, a liquid-filled stationary enclosed chamber of constant volume, communicating means between said rotary chamber and said stationary chamber and indicating means connected to said stationary chamber and responsive to the change in volume of said rotary chamber to give an indication of the applied torque.

Claim 3

Torque sensing apparatus as claimed in claim 1 and including a casing housing the coupling member and at least a portion of both the input and output drive means, the casing providing a liquid-filled bath in which said coupling member and said portions of both the input and output drive means are immersed, the bath forming said stationary chamber and seal means located between said drive member and one end wall of said casing and between said other drive means and a second end wall of said casing.

Claim 4

Torque-sensing apparatus as claimed in claim 2 and including first and second sockets in the respective first and second end walls of said casing and said seal means comprises a first collar device surrounding said input drive means and a penetratIng said first socket, a second collar device surrounding said output drive means and penetrating said second socket and a seal between each of said collar devices and the bore of the respective socket.

Claim 5

Torque-sensing apparatus as claimed in claim 1 and including means fixedly connecting said coupling member to said second drive means and a spigot-and-socket connection between said coupling member and said drive member.

Claim 6

Torque-sensing apparatus as claimed in claim 4 wherein said spigot-and-socket connection comprises at least one helical slot in the outer surface of said drive member and a cooperating slot-engaging pin on the inner surface of said coupling member.

Claim 7

Torque-sensing apparatus comprising rotary input drive means, rotary output drive means, a first drive member included in said input drive means, a second drive member included in said output drive means, a coupling member for drivingly connecting said input and said output drive means, a liquid-filled rotary enclosed chamber formed by said coupling member and an end wall of each of said first and second drive members, the coupling member being connected to said drive members so that under load conditions said drive members are displaceable relative to said coupling member to vary the volume of said chamber to an extent proportional to the applied torque, a liquid-filled stationary chamber of constant volume, communicating means between said rotary chamber and said stationary chamber and indicating means connected to said stationary chamber and responsive to the change in volume of said rotary chamber to give an indication of the applied torque.

Claim 8

Torque-sensing apparatus comprising rotary input drive means, rotary output drive means, a first drive member included in said input drive means, a second drive member included in said output drive means, a coupling member for drivingly connecting said input and said output drive means, a liquid-filled rotary enclosed chamber formed by said coupling member and an end wall of each of said first and second drive members, the coupling member being connected to said drive members so that under load conditions said drive members are displaceable relative to said coupling member to vary the volume of said chamber to an extent proportional to the applied torque, a liquid-filled stationary chamber of constant volume, communicating means between said rotary chamber and said stationary chamber and indicating means connected to said stationary chamber and responsive to the change in volume of said rotary chamber to give an indication of the applied torque.

Claim 9

Torque-sensing apparatus as claimed in claim 6 and including a stationary collar surrounding said coupling member, a liquid reservoir in said collar constituting said stationary chamber and seal means between said collar and said coupling member.

Claim 10

Torque-sensing apparatus as claimed in claim 6 and including a casing housing the coupling member and at least a portion of both the input and output drive means, the casing providing a liquid-filled bath in which said coupling member and said portions of both the input and output drive means are immersed, the bath forming said stationary chamber and seal means located between each of said drive members and respective end walls of said casing.

Claim 11

Torque-sensing apparatus as claimed in claim 8 and including first and second sockets in the respective end walls of said casing and said seal means comprises a first collar device surrounding said input drive means and penetrating said first socket, a second collar device surrounding said output drive means and penetrating said second socket and a seal between each of said collar devices and the bore of the respective socket.

Claim 12

Torque-sensing apparatus as claimed in claim 6 and including a first spigot-and-socket connection between said first drive member and said coupling member and a second spigot-and-socket connection between said second drive member and said coupling member.

Claim 13

Torque-sensing apparatus as claimed in claim 10 wherein said spigot-and-socket connections each comprise at least one helical slot in the outer surface of the respective drive member and a cooperating slot engaging pin on the inner surface of said coupling member.

Claim 14

Torque-sensing apparatus comprising a first shaft, a second shaft, a drive member for said first shaft, first coupling means between said first shaft and said drive member allowing the transmission of rotary movement between said first shaft and said drive member and allowing axial displacement of said drive member with respect to said first shaft, second coupling means secured to said second shaft and surrounding said drive member, an enclosed chamber formed by said second coupling means and by the respective end walls of said second shaft and said drive member, said second coupling means being so connected to said drive member that under load conditions irrespective of the direction of rotation of said first and second shafts, said drive member is axially displaceable with respect to said first shaft and with respect to said second coupling means to vary the volume of said chamber to an extent proportional to the applied torque and indicating means responsive to the change in volume of said chamber to give an indication of the applied torque.

Claim 15

Torque-sensing apparatus comprising a first shaft, a second shaft, a drive member for said first shaft, first coupling means between said first shaft and said drive member allowing the transmission of rotary movement between said first shaft and said drive member and allowing axial displacement of said drive member with respect to said first shaft, second coupling means secured to said second shaft and surrounding said drive member, an enclosed chamber formed by said second coupling means and by the respective end walls of said second shaft and said drive member, said second coupling means being so connected to said drive member that under load conditions irrespective of the direction of rotation of said first and second shafts, said drive member is axially displaceable with respect to said first shaft and with respect to said second coupling means to vary the volume of said chamber to an extent proportional to the applied torque and indicating means responsive to the change in volume of said chamber to give an indication of the applied torque.

Claim 16

Torque-sensing apparatus as claimed in claim 12 wherein said first coupling means includes a ball race located in opposed axial grooves in said drive member and said first shaft.

Claim 17

Torque-sensing apparatus comprising a driving shaft, a driven shaft, a first drive member for said driving shaft, a second drive member for said driven member, first coupling means between said driving shaft and said first drive member allowing the transmission of rotary movement from said driving shaft to said first drive member and allowing axial displacement of said first drive member with respect to said driving shaft, second coupling means between said driven shaft and said second drive member allowing the transmission of rotary movement from said second drive member to said driven shaft, third coupling means surrounding said first and second drive members, an enclosed chamber formed by said third coupling means and by the respective end walls of said first and second drive members, said third coupling means being so connected to said first and second drive members that under load conditions and irrespective of the direction of rotation of said first and second shafts said first and second drive means are axially displaceable with respect to said driving and driven shafts and with respect to said third coupling means to vary the volume of said chamber to an extent proportional to the applied torque and indicating means responsive to the change in volume of said chamber to give an indication of the applied torque.

Claim 18

Torque-sensing apparatus comprising a driving shaft, a driven shaft, a first drive member for said driving shaft, a second drive member for said driven member, first coupling means between said driving shaft and said first drive member allowing the transmission of rotary movement from said driving shaft to said first drive member and allowing axial displacement of said first drive member with respect to said driving shaft, second coupling means between said driven shaft and said second drive member allowing the transmission of rotary movement from said second drive member to said driven shaft, third coupling means surrounding said first and second drive members, an enclosed chamber formed by said third coupling means and by the respective end walls of said first and second drive members, said third coupling means being so connected to said first and second drive members that under load conditions and irrespective of the direction of rotation of said first and second shafts said first and second drive means are axially displaceable with respect to said driving and driven shafts and with respect to said third coupling means to vary the volume of said chamber to an extent proportional to the applied torque and indicating means responsive to the change in volume of said chamber to give an indication of the applied torque.

Claim 19

Torque-sensing apparatus as claimed in claim 14 wherein said first and second coupling means each include a ball race located in opposed axial grooves in said drive member and the respective shaft.