User Guide

ManualsBrandsBendix ManualsOtherE-7 DUAL BRAKE VALVE

SD-03-818

Bendix

E-7

™

Dual Brake Valve

valve closes, the secondary inlet valve is moved off its seat

allowing secondary air pressure to flow out the delivery port.

Because of the small volume of air required to move the

relay piston, action of the secondary circuit portion of the

valve is almost simultaneous with the primary circuit

portion.

APPLYING: LOSS OF AIR IN SECONDARY

CIRCUIT

Should air be lost in the secondary circuit, the primary

circuit portion will continue to function as described above

under Normal Operation: Primary Circuit Portion.

DESCRIPTION

The Bendix

E-7

™

dual brake valve is a suspended,

pedal-operated type brake valve with two separate supply

and delivery circuits for service and emergency braking,

which provides the driver with a graduated control for apply-

ing and releasing the vehicle brakes.

The circuits in the E-7

™

dual brake valve are identified as

follows: The primary circuit portion is that portion of the valve

between the spring seat which contacts the plunger and the

relay piston; the secondary circuit portion is that portion

between the relay piston and the exhaust cavity.

The primary circuit portion of the valve is similar in operation

to a standard single-circuit air brake valve, and under nor-

mal operating conditions the secondary circuit portion is

similar in operation to a relay valve.

The primary circuit portion of the valve is part of a removable

cage which also houses the relay piston and the cage which

can be removed without removing the entire brake valve.

Both primary and secondary circuit portions of the E-7

™

dual brake valve use a common exhaust protected by an

exhaust check valve.

OPERATION

APPLYING: NORMAL OPERATION - PRIMARY

CIRCUIT PORTION

When the brake pedal is depressed, the plunger exerts force

on the spring seat, rubber graduating spring, and primary

piston. The primary piston which contains the exhaust valve

seat, closes the primary exhaust valve. As the exhaust valve

closes, the primary inlet valve is moved off its seat allowing

primary air pressure to flow out the delivery port.

APPLYING: NORMAL OPERATION -

SECONDARY CIRCUIT PORTION

When the primary inlet valve is moved off its seat, air is

permitted to pass through the bleed passage and enters the

relay cavity. The air pressure moves the relay piston, and

the relay piston, which contains the exhaust seat, closes

the secondary exhaust valve. As the secondary exhaust

SECONDARY

DELIVERY

PRIMARY

DELIVERY

PRIMARY

SUPPLY

SECONDARY

SUPPLY

MOUNTING

PLATE

FIGURE 1 - E-7

™

DUAL BRAKE VALVE

Summary of content (8 pages)

PAGE 1
SD-03-818 ® Bendix® E-7™ Dual Brake Valve DESCRIPTION The Bendix ® E-7 ™ dual brake valve is a suspended, pedal-operated type brake valve with two separate supply and delivery circuits for service and emergency braking, which provides the driver with a graduated control for applying and releasing the vehicle brakes.
PAGE 2
APPLYING: LOSS OF AIR IN PRIMARY CIRCUIT PREVENTIVE MAINTENANCE Should air be lost in the primary circuit, the function will be as follows: As the brake pedal is depressed and no air pressure is present in the primary circuit supply and delivery ports, the primary piston will mechanically move the relay piston allowing the piston to close the secondary exhaust valve and open the secondary inlet valve and allow air pressure to flow out the delivery port.
PAGE 3
INLET-EXHAUST ASSEMBLY (1) EXHAUST CHECK VALVE RETAINER (17) SCREW (21) O-RING (2) WASHER (22) O-RING (3) RELAY SPRING (5) DIAPHRAGM (13) RETAINER (20) INLET-EXHAUST ASSEMBLY (4) O-RING (11) O-RING (9) O-RING (7) O-RING (6) O-RING (12) PISTON SPRING (8) SPRING SEAT NUT (16) RETAINER (18) STEM SPRING (23) RUBBER SPRING (10) SPRING SEAT (15) LOCK NUT (14) RUBBER SPRING SEAT (19) STOP BUTTON PLUNGER ROLLER FULCRUM PIN PEDAL SEALING RINGS MANIFOLD* *OPTIONAL MANIFOLD FOR INSTALLATIONS REQU
PAGE 4
LEAKAGE CHECK 1. Make and hold full brake application. 2. Coat the exhaust port and body of the brake valve with soap solution. 3. Leakage not to exceed a 1” bubble in 3 seconds in both the applied and released position. If the brake valve does not function as described above or leakage is excessive, it is recommended that it be replaced with a genuine Bendix new or remanufactured unit, available at your local authorized Bendix parts outlet. REMOVAL (IF NECESSARY) 1.
PAGE 5
7. Insert relay piston spring (5) and relay piston in top end of lower static piston, and primary circuit piston spring (8) and primary circuit piston assembly in the bottom of lower static piston. 8. Install stem bolt through bore of relay piston, invert entire lower static piston assembly and position over a screwdriver mounted in a vise. Engage screwdriver blade in slot in head of stem. 9.
PAGE 6
GENERAL SAFETY GUIDELINES WARNING! PLEASE READ AND FOLLOW THESE INSTRUCTIONS TO AVOID PERSONAL INJURY OR DEATH: When working on or around a vehicle, the following general precautions should be observed at all times. 1. Park the vehicle on a level surface, apply the parking brakes, and always block the wheels. Always wear safety glasses. 2. Stop the engine and remove ignition key when working under or around the vehicle.
PAGE 7