Bendix Commercial Vehicle Systems BRAKE CHAMBERS User Manual

Bendix® Brake Chambers

FIGURE 1 - BENDIX®

BRAKE CHAMBER

DESCRIPTION

SD-02-1302

Different size brake chambers are identied by numbers

which specify the effective area of the diaphragm. For example, a brake chamber that has 30 square inches of “effective area” (the area of the diaphragm that generates force on the push plate), is commonly referred to as a type 30 brake chamber. See Figure 2.

Since one side of a brake chamber diaphragm is exposed to the applying air pressure and the other side to atmospheric pressure, the chamber has a pressure and a non-pressure side. The non-pressure plate is usually vented to atmosphere by vent holes. Installations where the chamber must be weather-proof, venting is accomplished through a

variety of methods. Consult the OEM for specic details.

The standard diaphragm material is a compound of natural rubber with a fabric interior of nylon. Neoprene-nylon diaphragms are optionally available.

The brake chamber is a diaphragm-type actuator which converts the energy of air pressure into mechanical force. See Figure 2. The diaphragm is held between the pressure plate (A) and non-pressure plate (B) by either a one- or two-piece clamp ring (C).

Side Inlet Port

(shown plugged)

Pressure Plate (A)

Diaphragm

Push Plate

Center Inlet Port

Clamp Ring Nuts

& Bolts

Vent

Spring

OPERATION

Controlled air pressure enters the brake chamber through the inlet port and acts upon the diaphragm moving the push plate and rod assembly forward.

Non-Pressure Plate (B)

Mounting

Bolts

Push Plate and Push

Rod Assy.

Lock Nut

Yoke

Clamp Ring (C)

FIGURE 2 - CUT-AWAY VIEW

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 guidelines should be observed AT ALL TIMES:

▲ Park the vehicle on a level surface, apply the parking

brakes and always block the wheels. Always wear personal protection equipment.

▲ Stop the engine and remove the ignition key when

working under or around the vehicle. When working in the engine compartment, the engine should be shut off and the ignition key should be removed. Where circumstances require that the engine be in operation, EXTREME CAUTION should be used to prevent personal injury resulting from contact with moving, rotating, leaking, heated or electrically-charged components.

▲ Do not attempt to install, remove, disassemble or

assemble a component until you have read, and thoroughly understand, the recommended procedures. Use only the proper tools and observe all precautions pertaining to use of those tools.

▲ If the work is being performed on the vehicle’s air brake

system, or any auxiliary pressurized air systems, make certain to drain the air pressure from all reservoirs before beginning ANY work on the vehicle. If the vehicle is equipped with a Bendix Bendix AD-9si™ air dryer, be sure to drain the purge reservoir.

▲

Following the vehicle manufacturer’s recommended procedures, deactivate the electrical system in a manner

that safely removes all electrical power from the vehicle ▲ Never exceed manufacturer’s recommended pressures. ▲ Never connect or disconnect a hose or line containing

pressure; it may whip. Never remove a component or

plug unless you are certain all system pressure has

been depleted. ▲ Use only genuine Bendix

components and kits. Replacement hardware, tubing,

hose, ﬁ ttings, etc. must be of equivalent size, type

and strength as original equipment and be designed

speciﬁ cally for such applications and systems.

▲ Components with stripped threads or damaged parts

should be replaced rather than repaired. Do not

attempt repairs requiring machining or welding unless

speciﬁ cally stated and approved by the vehicle and

component manufacturer. ▲ Prior to returning the vehicle to service, make certain all

components and systems are restored to their proper

operating condition. ▲ For vehicles with Automatic Traction Control (ATC),

the ATC function must be disabled (ATC indicator

lamp should be ON) prior to performing any vehicle

maintenance where one or more wheels on a drive axle

are lifted off the ground and moving. ▲ The power MUST be temporarily disconnected

from the radar sensor whenever any tests USING A

DYNAMOMETER are conducted on a Bendix

Advanced ▲ You should consult the vehicle manufacturer's

operating and service manuals, and any related

literature, in conjunction with the Guidelines above.

DRM™ dryer reservoir module, or a Bendix

™

-equipped vehicle.

AD-IS® air dryer system, a

brand replacement parts,

Wingman®

WARNING: Not all wheels and valve stems are

compatible with Bendix Air Disc Brakes. Use only wheels and valve stems approved by the vehicle manufacturer to avoid the risk of valve stem shear and other compatibility issues.

WARNING: AVOID CREATING

DUST. POSSIBLE CANCER AND LUNG DISEASE HAZARD.

While Bendix Spicer Foundation Brake LLC does not offer asbestos brake linings, the long-term affects of

some non-asbestos ﬁ bers have not been determined.

Current OSHA Regulations cover exposure levels to some components of non-asbestos linings, but not all. The following precautions must be used when handling these materials.

▲ Avoid creating dust. Compressed air or dry

brushing must never be used for cleaning brake assemblies or the work area.

▲ Bendix recommends that workers doing brake

work must take steps to minimize exposure to airborne brake lining particles. Proper procedures to reduce exposure include working in a well-ventilated area, segregation of areas

where brake work is done, use of local ﬁ ltered

ventilation systems or use of enclosed cells with

ﬁ ltered vacuums. Respirators approved by the

Mine Safety and Health Administration (MSHA) or National Institute for Occupational Safety

and Health (NIOSH) should be worn at all times during brake servicing.

▲ Workers must wash before eating, drinking or

smoking; shower after working, and should not wear work clothes home. Work clothes should be vacuumed and laundered separately without shaking.

▲ OSHA Regulations regarding testing, disposal

of waste and methods of reducing exposure for asbestos are set forth in 29 Code of Federal Regulations §1910.001. These Regulations provide valuable information which can be utilized to reduce exposure to airborne particles.

▲ Material Safety Data Sheets on this product, as

required by OSHA, are available from Bendix. Call 1-800-247-2725 and speak to the Tech Team or e-mail techteam@bendix.com.

+ 2 hidden pages