A drum brake device is provided which facilitates the pre-mounting of a long link, without increasing the number of components or the cost of the device. The long link (44) is pivotable on the central segment of one brake shoe (13). An engagement hook (48) protrudes from one or the other of the long link (44) or the one brake shoe (13). A notched groove (25) is formed in the other component thereof. The engagement hook (48) is inserted into the notched groove (25). The rotation of the long link (44) relative to the one brake shoe (13) will cause the long link (44) and one brake shoe (13) to be superimposable and detachable.

A drum brake device is provided which facilitates the pre-mounting of a long link, without increasing the number of components or the cost of the device. The long link (44) is pivotable on the central segment of one brake shoe (13). An engagement hook (48) protrudes from one or the other of the long link (44) or the one brake shoe (13). A notched groove (25) is formed in the other component thereof. The engagement hook (48) is inserted into the notched groove (25). The rotation of the long link (44) relative to the one brake shoe (13) will cause the long link (44) and one brake shoe (13) to be superimposable and detachable.

This invention provides a duo-two leading type drum brake device which simplifies a drum brake structure as well as improves a transmission efficiency of a application force from a shoe actuator to brake shoes. A pivot lever 60 has an intermediate portion pivotally supported on the brake shoes 40. A shoe-actuator 20 is positioned adjacent to the first anchors 30, 30 and being disposed between the ends 60a, 50a of the pivot lever 60 and the other brake shoe 50. A strut 70 is positioned between and functionally engaged with the other ends 60b, 50b of the pivot lever 60 and the other brake shoe 50. An application force of the shoe actuator 20 is transmitted to the brake shoe 40 via a pivot section of the pivot lever 70 and transmitted to the other brake shoe 50 directly from the shoe-actuator 20 and indirectly via the strut 70.

A brake system for off-road vehicles of the type including an operator seat, a brake pedal and a hydraulic brake responsive to operator actuation on the brake pedal. The brake system includes a tank for hydraulic fluid, an electric pump hydraulically connected to the tank, a pressure modulating valve actuated by the brake pedal and a flow control valve for controlling the flow of pressurized hydraulic fluid between the pump, pressure modulating valve and brake. During normal braking operation, a switch responsive to operator actuation of the brake pedal causes to provide pressurized hydraulic fluid to the brake through the flow control valve. The return flow of pressurized fluid to the tank is modulated by the pressure modulating valve in response to operator actuation of the brake pedal to control the braking pressure. The flow control valve is responsive to the presence of an operator in the operator compartment, and is coupled to a switch. In the event an unoccupied seat condition is sensed, the switch actuates the pump, and the flow control valve is switched to a flow path which routes all the pressurized fluid to the brake. The brake is thereby automatically actuated when an unoccupied seat condition is sensed. The pressure modulating valve also includes a secondary fail-safe chamber which is actuated by the brake pedal to supply hydraulic fluid to the brake during a fail-safe mode when the pump is not operating.

A hydraulic braking system for a towed vehicle provides actuation of the hydraulic pump motor of the towed vehicle responsive to an electrical switch which is closed upon application of the brake pedal of the towing vehicle. However, even after actuation of the hydraulic pump, the towed vehicle brakes are only able to be applied in response to sensed relative movement of the towing and towed vehicle toward each other. A break-away switch sets the trailer brakes in the event of accidental separation of the towed vehicle from the towing vehicle. The control valve may be used in other situations to control a hydraulic pump and associated hydraulic braking system.