Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T7/00—Brake-action initiating means
  • B60T7/12—Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T7/00—Brake-action initiating means
  • B60T7/12—Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger
  • B60T7/16—Brake-action initiating means for automatic initiation; for initiation not subject to will of driver or passenger operated by remote control, i.e. initiating means not mounted on vehicle

Definitions

• This invention relates to braking systems and more particularly concerns such systems which are operable to actuate the brakes of a vehicle when it is in a reverse condition. It is known to operate the brakes of a vehicle by means of a system which is operable by a reverse gear actuated switch and a detector at the rear of the vehicle the arrangement being such that the brakes are activated only when the detector contacts an object and the switch is actuated by engagement of reverse gear.
• U.S. Patent No. 2,588,815 (Fasolino) describes various _, reverse braking systems using electrical switches operated by the vehicle gear lever and a detector at the rear of ⁇ the vehicle to operate a device which causes operation of the brakes.
• the device is a power solenoid acting on the brake pedal linkage and in another embodiment is a solenoid valve arranged to apply vacuum from the intake manifold to a pneumatic cylinder connected by a flexible cable to the brake pedal linkage.
• U.K. Patent No. 1470129 (Ebbeson et al) describes a similar system actuated by electrical switches and an electromagnetically controlled pneumatic valve. This valve is connected to the vacuum servo of the braking system of the vehicle to control the application of atmospheric pressure to the vacuum chamber of the servo and thereby cause the brakes to be actuated whilst the electrical switch controlled by the detector is actuated.
• the present invention provides an improved reverse actuated auxiliary braking system for use with hydraulic vehicle braking systems.
• I provide an auxiliary braking system for a vehicle which system comprises means arranged to be actuated by the engagement of reverse gear of the vehicle, said means being connected to operate a valve, a detector connected to operate a valve, said valve or valves being arranged in a fluid circuit including a pump for generating pressurised fluid whereby when said valve or valves is or are in an operated condition they permit pressurised fluid to flow and to cause actuation of the braking system.
• the pressurised fluid may be a liquid or gas and is preferably air.
• the reverse gear actuated means is a switch.
• the reverse gear actuated switch and the ' detector may be connected to operate a single valve or two valves arranged in series.
• the flow of pressurised fluid may be utilised to pressurise the hydraulic system of the vehicle, either directly or indirectly, or may be utilised to operate mechanical means to actuate the brakes of the vehicle.
• the pressurised fluid is used to operate a hydraulic cylinder which is connected into the hydraulic braking circuit of the vehicle, either as an auxiliary cylinder, as an existing cylinder in the circuit or as a combination of both with the cylinders arranged in series or in parallel.
• the hydraulic cylinder may be used to operate mechanical means to actuate the brakes; for example it may operate the linkage between the brake pedal and the servo of a servo-assisted braking system.
• a simple arrangement is to include the cylinder in a linkage so that when the cylinder is contracted the brake linkage operates normally but when the cylinder is expanded it operates the brakes independently of the foot brake pedal.
• the auxiliary braking system further comprises a mechanical arrangement for operating the braking system.
• the mechanical arrangement may include a rod connected into the existing brake circuit of the vehicle and adapted to actuate the vehicle braking system.
• the rod may be movable between a first position in which the braking system is not actuated, and a second position in which the braking system is actuated.
• a further valve may be provided for moving the rod between the first and second positions.
• the vehicle braking system may include a brake actuation rod connected to a brake pedal, and a piston rod for operating a hydraulic brake cylinder; the hydraulic brake cylinder operates, the brakes.
• the rod of the auxiliary braking system can be disposed between the brake actuation rod and the piston rod, so that the brakes can be applied normally by the brake pedal, or through the auxiliary braking system.
• Figure 1 is a schematic diagram of one form of auxiliary braking system according to the invention.
• FIG. 2 is a schematic diagram of another form of the invention.
• Figure 3 is a schematic diagram of yet another form of the invention
• Figure 4 is a schematic diagram of yet another form of the invention
• Figure 5 is a schematic diagram of yet a further form of the invention.
• Figure 6 is a diagram of a valve suitable for use in the system of Figures 1 to 5;
• Figure 7 is a schematic diagram of yet another form of the invention.
• Figure 1 shows a system in which pressurised hydraulic fluid is generated by a cylinder and connected into the existing braking circuit by means of an additional valve (not shown).
• the circuit is based on an air-operated valve 10 which may be of the type shown in Figure 6. Control air is provided to the valve 10 along line 11 which is connected to a pneumatic detector 12 located at the rear of the vehicle. When the valve 10 is not operated the outlet is connected to atmosphere which prevents any accidental build-up of air pressure.
• Pressurised air is generated by a pump 13 which is connected in an electrical circuit including a gear lever-operated switch 14 and a solenoid valve 15.
• pump 13 When reverse gear is engaged pump 13 is energised and provides pressurised air through non-return valve 16 -to the air-operated valve 10.
• valve 10 When the pneumatic detector 12 is activated, e.g. by contact with an obstruction, air in line 11 will operate valve 10 to permit pressurised air from the pump 13 to pass into the cylinder 17.
• This incorporates a piston 18 and piston rod 19 which is mechanically connected to a hydraulic cylinder 20.
• the hydraulic cylinder 20 is a conventional type which includes a piston 21 which operates against a return spring 22 and which incorporates a valve element 23 so that when it is moved against the spring pressure it closes off the port 24 connected to fluid reservoir 25 and causes pressurised hydraulic fluid to be applied to the line 26 which is connected into the existing hydraulic fluid system of the vehicle by means of a valve (not shown) or by connection into the existing brake master cylinder of the vehicle.
• the pump 13 will generate pressurised air only when operated by the gear lever switch 14 and thus when the vehicle is in a reversing condition. When the vehicle is not in a reversing condition the pump 13 does not operate and the valve 15 remains closed.
• the pump 13 may generate noise and to this end it is preferred to locate it near the rear of the vehicle where it will act as a warning device that the vehicle is in a reversing condition. It has been found that the valve 10 can be operated by a very small change in pressure in the line 11 so that a very sensitive system is achieved.
• Figure 2 shows a modification of the system shown in Figure 1 in which the cylinders 17 and 20 are replaced by a single cylinder 27 which is operated directly by the air pressure in the line 28 from the valve 10.
• FIG. 3 A further alternative embodiment of the invention is shown schematically in Figure 3.
• the cylinder 30 is air-operated and includes an air-operated piston 31 with a piston rod 32 ' and return spring 33.
• the line 28 is connected in a circuit as shown in Figure 1 but the connection to the braking system of the vehicle is mechanical rather than hydraulic.
• the piston rod 32 is connected to part of the brake pedal linkage of the vehicle at 34 and the cylinder 30 is connected to the linkage at 35.
• the linkage can be moved either by pressure of the driver's foot on the pedal 36 or by movement of the piston rod 32 in response to air pressure in the line 28 caused by simultaneous operation of the gear lever switch 14 and the pneumatic detector 12.
• the system can be simplified by using a single solenoid valve to replace the valves 10 and 15 in the air circuit of Figure 1 and an air-operated electrical switch in the electrical circuit.
• the cylinder 40 can be similar to the cylinders 20, 27 or 30 in Figures 1 to 3 respectively.
• the pneumatic detector 12 and air line 11 are connected to an air-operated switch 41 which is connected to the solenoid valve 42.
• the gear lever-operated switch 14 is connected as in Figure 1 so as to operate pump 13 which supplies pressurised air through non-return valve 16 to the solenoid valve 42.
• both switch 14 and switch 41 are operated the solenoid valve will pass pressurised air to the cylinder 40 causing actuation of the vehicle brakes as previously described.
• An electrical relay 43 may be included so that when switch 41 is operated and then released the solenoid valve 42 will remain operated until the electrical circuit to the relay 43 is broken by moving the gear lever out of reverse and opening ' switch 14. This causes the brakes of .the vehicle to remain actuated after the signal from the pneumatic detector 12 has been interrupted so that ' the vehicle can be moved only by first disengaging reverse gear after the auxiliary brake system has been operated.
• FIG. 5 illustrates two further modifications which are within the scope of this invention.
• an alternative means for holding the brakes on after the signal from the pneumatic detector has been released is the use of an air-operated valve 50. Whilst air pressure remains in the line 28 the valve 42 will remain operated.
• the hydraulic cylinder 20 is part of an auxiliary circuit as shown in Figure 1 but the outlet line 26 for pressurised hydraulic fluid is connected into the fluid circuit of the vehicle braking system by connecting the line 26 to the fluid reservoir inlet 52 of the cylinder 51.
• pressurised fluid is generated by the cylinder 20 in response to the pneumatic detector 12 being operated, it is applied to the master hydraulic cylinder 51 of the vehicle braking system and pressurises outlet line 53 to operate the brakes of the vehicle.
• the cylinder 51 is operated by means of the foot brake linkage 54 and is not affected by the existence of the auxiliary master cylinder 20 as the line 26 is closed when the cylinder is operated. Topping up of the system is derived from the fluid reservoir 25.
• valve 10 and the non-return valve 16 serve to retain the pressurised air.
• Inlet port 64 is for pressurised air from the pump and inlet port 60 is connected to the line from the pneumatic detector 12.
• a suitable valve is marketed under the name "Boostermite” Type 5BV-913 which can be arranged to operate on a differential pressure of one half to three inches of water.
• Figure 7 illustrates another embodiment of the invention.
• the gear lever switch 14 is connected to a power source (not shown), and also to the pump 13 via electrical line 70.
• the pump 13 is connected to a switch 71 via an electrical line 72.
• the switch 71 is a low sense electrical switch, for example, the switch sold under the name HERGAIR. In an alternative embodiment the switch 71 can be replaced by a
• the switch 71 is pilot operated; a detector 73 is connected to the switch 71 via an air line 74. Air flow, through the air line 74 from the detector 73 provides the pilot operation of the switch 71.
• the detector 73 can include an air bag, and compression of the air bag causes air flow through the air line 74.
• the switch 71 is connected to a solenoid 75 via an electrical line 76.
• a pilot operated relay switch 77 is connected to the solenoid 75 via an electrical line 78 and the line 76.
• the relay switch 77 is also connected to the line 70 via a line 79.
• the solenoid 75 is connected to the pump 13 via an air line 80, and is provided with an exhaust 81.
• the solenoid 75 is connected to the relay valve 77 via an air line 82.
• the relay valve 77 is connected to a further valve
• the valve 83 is pilot operated by means of the air line 84.
• the valve 83 shown in Figure 7 is a diaphragm air valve and includes a flexible diaphragm 85 which is connected to a movable rod 86.
• the valve 83 has a chamber 94 which communicates with the line 84, and a separate chamber 95 which is provided on the other side of the diaphragm 85 to the chamber 94.
• the valve 83 could be a piston air cylinder in which the movable rod 86 is connected to a piston which replaces the diaphragm 85.
• An end 86a of the rod 86 may engage an end of a brake actuating rod 87 and an end 86b of the rod 86 may engage an end of a piston rod 88.
• the brake actuating rod 87 is connected to a brake pedal (not shown) through a vacuum servo assistor 89.
• the piston rod 88 is connected to a piston 90 of a master brake cylinder 91.
• the master cylinder 91 is provided with a fluid reservoir 92 and a fluid outlet 93 which is connected to hydraulic brakes (not shown).
• the rod 86 moves with the diaphragm 85, to which it is connected, towards the piston rod 88.
• the end 86b_ of the rod 86 engages the piston rod 88 which causes movement of the piston 90 to actuate the brakes.
• valve 83 comprises a piston air cylinder
• a spring may be provided ! to return the piston to the original position. If desired the spring may also be used with the diaphragm 85 to assist return to the original position.
• a mechanical arrangement is provided in the existing brake system for actuating the brakes.
• the brakes can be actuated either by the brake -pedal, or when reverse gear is selected and the detector 73 is actuated.

Landscapes

• Engineering & Computer Science (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Braking Systems And Boosters (AREA)
• Valves And Accessory Devices For Braking Systems (AREA)
• Regulating Braking Force (AREA)
• Valve Device For Special Equipments (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10565875

Family Applications (1)

Country Status (9)

Families Citing this family (1)

Family Cites Families (5)

• 1984
  • 1984-08-25 GB GB848421661A patent/GB8421661D0/en active Pending
• 1985
  • 1985-08-27 JP JP50369785A patent/JPS62500094A/ja active Pending
  • 1985-08-27 BR BR8506894A patent/BR8506894A/pt unknown
  • 1985-08-27 WO PCT/GB1985/000383 patent/WO1986001474A1/en not_active Application Discontinuation
  • 1985-08-27 EP EP19850904134 patent/EP0191819A1/en not_active Withdrawn
  • 1985-08-27 GB GB08609890A patent/GB2176553A/en not_active Withdrawn
  • 1985-08-27 AU AU47728/85A patent/AU4772885A/en not_active Abandoned
• 1986
  • 1986-04-23 DK DK187786A patent/DK187786A/da not_active Application Discontinuation
  • 1986-04-25 FI FI861752A patent/FI861752A0/fi not_active Application Discontinuation
  • 1986-04-25 NO NO861632A patent/NO861632L/no unknown

Non-Patent Citations (1)

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