# US 5,707,071 A · Sway stabilisation system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,707,071 A - Document ID: US5707071A - Status: Granted - Kind: A - Application number: 08/416,781 - Filed: 1995-06-15 - Granted: 1998-01-13 - Earliest claimed: 1992-10-13 - Assignees: Presbat Products Pty. Ltd. - Inventors: Leslie Walter Prestidge; Lambert Von Batenburg - Web page: https://patentgrep.com/patent/US5707071A ## CPC - B62D 53/0878: {the fifth wheel coupling incorporating braking or restraining means} - B60D 1/30: for sway control {; Sway alarm means} - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) - B60D: VEHICLE CONNECTIONS ## Abstract A sway stabilization system to inhibit an undesirable sideways sway between a towed vehicle (15) and a lead vehicle (14) comprises a brake assembly (17) having towed vehicle parts and lead vehicle parts operatively connected together in parallel with the draw bar and hitch assembly (16). The towed vehicle parts include a sway transmission member (21) secured to a draw bar (18). The lead vehicle parts include a braking surface carrier member (22), which engages with the draw bar (18), for pivoting movement with the sway transmission member (21) about the axis of the hitch pin, the braking surface carrier member (22) being subject to braking action by clutch plates (33, 34) in response to undesirable sway being detected by a coupling sensor (36). ## Claims ### Claim 1 A sway stabilization system to inhibit an undesirable side-ways sway between a towed vehicle and a lead vehicle, the system having a brake assembly including brake means disposed between the vehicles, sway detection means responsive to undesirable sway and a brake control means responsive to detection of undesirable sway by the sway detection means to initiate operation of the brake means, the brake means being operable to inhibit undesirable sway and the brake control means being adapted to automatically actuate the brake means in response to detected undesirable sway while the vehicles are travelling, wherein the towed vehicle and lead vehicle are coupled together using a hitch pin and draw bar assembly, the brake assembly comprising a hitch pin and draw bar follower means having opposed ends coupled to the towed vehicle and lead vehicle respectively in order to follow the hitch pin and draw bar assembly as the vehicles travel, one end of the hitch pin and draw bar follower means including a sway transmission member protruding from the towed vehicle in parallel with the draw bar and extending toward the lead vehicle, and the opposed end of the hitch pin and draw bar follower means having a hollow pivotable braking surface carrier means secured to the lead vehicle and being adapted to receive the sway transmission member and rotate therewith in response to movement of the draw bar relative to the hitch. ### Claim 2 (depends on 1) The system according to claim 1 wherein the sway transmission member is moveably secured to the towed vehicle to allow limited torsional movement as the vehicles travel so as not to interfere with the normal operation of the hitch pin and the draw bar assembly. ### Claim 3 (depends on 1) The system according to claim 1 wherein the brake means comprises a horizontal braking surface secured to the pivotable braking surface carrier means and a controllably movable non-pivotable braking surface adapted to engage a pivotable braking surface secured to the pivotable braking surface carrier means in response to the brake control means initiating braking in order to automatically resist the pivotal movement of the draw bar relative to the hitch, thereby providing a braking action against undesirable sway. ### Claim 4 (depends on 3) The system according to claim 3 wherein the non-pivotable braking surface is driven into braking contact with the pivotable braking surface using a drive means operating under influence of the brake control means in response to undesirable sway being detected by the sway detection means. ### Claim 5 (depends on 1) The system according to claim 1 wherein the braking surface carrier means is preferably moveably secured to the lead vehicle to allow limited torsional movement as the vehicles travel so as not to interfere with the normal operation of the hitch pin and the draw bar assembly. ### Claim 6 A sway stabilization system for controlling undesirable sway of a towed vehicle relative to a lead vehicle, said vehicles being coupled together by a hitch pin and a draw bar, said sway stabilization system including: hitch pin and draw bar follower means including a sway transmission member adapted for mounting to the towed vehicle for relative pivoting movement in parallel with the draw bar about said hitch pin and a pivotable braking surface carrier means adapted for securement to the lead vehicle, said pivotable braking surface carrier means being adapted to cooperate with said sway transmission member for pivoting movement therewith in response to movement of the draw bar relative to the hitch pin; brake means adapted to selectively apply a braking force to said pivotable braking surface carrier means to inhibit pivoting movement of said draw bar relative to said hitch pin; sway detection means for detecting relative pivoting movement of said draw bar about said hitch pin; and brake control means for automatically actuating said brake means in response to detected undesirable pivoting movement of said draw bar. ### Claim 7 (depends on 6) A sway stabilization system according to claim 6, wherein said sway transmission member includes mounting means for mounting said sway transmission member to said draw bar. ### Claim 8 (depends on 7) A sway stabilization system according to claim 7, wherein said mounting means allows limited movement of said sway transmission member relative to said draw bar. ### Claim 9 (depends on 8) A sway stabilization system according to claim 8, wherein said mounting means includes a resilient mounting member. ### Claim 10 (depends on 7) A sway stabilization system according to claim 7, wherein said braking surface carrier means includes mounting means for mounting said braking surface carrier means to said lead vehicle for limited movement relative thereto. ### Claim 11 (depends on 10) A sway stabilization system according to claim 10, wherein said mounting means includes a resilient mounting member. ### Claim 12 (depends on 7) A sway stabilization system according to claim 7, wherein said braking surface carrier means has at least one horizontal braking surface and said brake means is adapted to engage said at least one horizontal braking surface to apply said braking force. ### Claim 13 (depends on 12) A sway stabilization system according to claim 12, wherein said braking surface carrier means has two opposed horizontal braking surfaces and said brake means is adapted to engage both of said surfaces. ### Claim 14 (depends on 13) A sway stabilization system according to claim 13, wherein said brake means includes a pair of opposed brake pads adapted to engage said opposed horizontal braking surfaces respectively. ### Claim 15 (depends on 14) A sway stabilization system according to claim 14, wherein said opposed brake pads are driven into engagement with said horizontal braking surfaces by pneumatically operated pistons. ### Claim 16 (depends on 7) A sway stabilization system according to claim 7, wherein said sway transmission member includes a bar portion and said braking surface carrier means has a recess adapted to receive said bar portion. ### Claim 17 (depends on 16) A sway stabilization system according to claim 16, wherein said spigot portion extends forwardly beyond said draw bar to allow engagement of said spigot portion in said recess prior to engagement of said draw bar with said hitch pin. ### Claim 18 (depends on 6) A sway stabilization system according to claim 6, wherein said sway detection means includes at least one sensor from the group consisting of: (i) a coupling transducer adapted to monitor angular position of the towed vehicle relative to the lead vehicle; (ii) a steering transducer adapted to monitor vehicle steering; (iii) a collision transducer adapted to sense a collision condition; and (iv) a footbrake transducer adapted to monitor operation of a footbrake operated by a driver of the vehicles. ### Claim 19 (depends on 18) A sway stabilization system according to claim 18, including a cab decision circuit for selectively actuating said brake means to inhibit undesirable sway, said decision circuit being adapted to receive data from at least one sensor selected from the group, which is a subgroup of the group specified in claim 18, consisting of: (i) said steering transducer adapted to monitor vehicle steering; (ii) said collision transducer adapted to sense a collision condition; and (iii) said footbrake transducer adapted to monitor operation of a footbrake operated by a driver of the vehicles. ### Claim 20 (depends on 19) A sway stabilization system according to claim 19, and further including a trailer decision circuit for selectively actuating said brake means in response to detection of undesirable sway by said coupling transducer. ### Claim 21 (depends on 20) A sway stabilization system according to claim 20, wherein said trailer decision circuit causes actuation of said brake means for a short period of time upon detection of oscillation of said towed vehicle above a predetermined frequency. ### Claim 22 (depends on 21) A sway stabilization system according to claim 21, wherein the coupling transducer is adapted to detect movement of said draw bar with respect to a predetermined position to determine said frequency of said oscillation. ### Claim 23 (depends on 6) A sway stabilization system according to claim 6, wherein the vehicles include a wheel braking system actuated by a footbrake and said brake means is adapted for operation independently of said wheel braking system. ### Claim 24 A sway stabilization system to inhibit an undesirable side-ways sway between a towed vehicle and a lead vehicle, the system having a brake assembly including brake means disposed between the vehicles, sway detection means responsive to undesirable sway and a brake control means responsive to detection of undesirable sway by the sway detection means to initiate operation of the brake means, the brake means being operable to inhibit undesirable sway and the brake control means being adapted to automatically actuate the brake means in response to detected undesirable sway while the vehicles are travelling, wherein the sway detection means includes at least one sensor from the group consisting of: (i) a coupling transducer adapted to monitor angular position of the towed vehicle relative to the lead vehicle; (ii) a steering transducer adapted to monitor vehicle steering; (iii) a collision transducer adapted to sense a collision condition; and (iv) a footbrake transducer adapted to monitor operation of a footbrake operated by a driver of the vehicles; and wherein the transducers supply data to a cab decision circuit with the steering transducer, collision transducer and footbrake transducer located on a cab of a prime mover, the cab decision circuit operating in conjunction with the data supplied from the transducers to actuate the brake means to inhibit undesirable sway, the system further comprising an independent trailer decision circuit which responds to undesirable sway being detected by the coupling transducer, where oscillation of the towed vehicle away from a predetermined position occurs more than once within a predetermined time period, by causing the application of the brake means for a short period of time, the application of the brake means being made when the coupling transducer detects the oscillation of the towed vehicle in the vicinity of the predetermined position.