Motor vehicle safety testing equipment-Technical requirements of verification-Part 7:Technical requirements of verification for axle (wheel) load scales
1 Scope
This standard specifies technical requirements and methods of verification for axle (wheel) load scale used to measure gravity load of each axle (wheel) for motor vehicles.
This standard is applicable to the verification of axle (wheel) load scale used for motor vehicle safety testing and axle (wheel) weight part in brake axle (wheel) duplicated checkout stands.
2 Normative References
The provisions of the following standard, through reference in this standard, constitute the provisions of this standard. At time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below.
GB/T 6587.7-1986 Basic Safety Tests for Electronic Measuring Instruments
3 Definitions
The following definitions are adopted in this standard.
3.1 Axle (wheel) weight
Gravity load of motor vehicle axle (wheel) loading weight, in N or kN.
3.2 Specified load
Maximum gravity load of axle (wheel) loading weight of the vehicle to be verified that the axle (wheel) load scale permits to bear.
3.3 Absolute value of difference for errors
Absolute value of difference for errors for paired (one left and one right) two independent wheel load scales to measure the wheel weight of motor vehicle when measuring the same load.
3.4 Safe limit load
Maximal load that may be imposed on the axle (wheel) load scale yet would not cause permanent change that exceeds the regulation to its performance characteristics.
4 Technical Requirements
4.1 Appearance and general requirements
4.1.1 The axle (wheel) load scale shall have clear nameplate, equipment name, equipment model, specified load, delivery number, manufacturer's name and delivery date.
4.1.2 Various controls such as switch, button, socket and wiring terminal shall have explicit text or symbol marking. The symbol marking shall meet the requirements of relevant standards. The controls shall be in flexible and reliable operation, and shall be free from such phenomena as looseness or blocking.
4.1.3 For pointer type display instrument, the panel shall be distinct, the pointer shall be free from bending, the gyration shall be stable and flexible, and shall be free from phenomena such as fluctuation and clamping. Digital display instrument shall be free from defects that affect the reading. The digital display value shall become stable within 5s. The retention time of indicating value shall not be less than 8s.
4.1.4 The bearing table-board shall be free from explicit deformation phenomenon such as warpage when bearing unbalancedly.
