1、 _ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising ther
2、efrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions. Copyright 2016 SAE International All rights reserved. No part of this
3、publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-49
4、70 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit HTTP:/STANDARDS.SAE.ORG/J2690_201610 SURFACE VEHICLE RECOMMENDED PRACTICE J2690 OCT2016 Issued 2012-01 Reaffirmed 2016
5、-10 Superseding J2690 JAN2012 Driveline Parking Brake Test Procedure for Medium Duty Vehicles RATIONALE J2690 has been reaffirmed to comply with the SAE five year review policy. 1. SCOPE This SAE Recommended Practice establishes uniform test procedures for friction based parking brake components use
6、d in conjunction with hydraulic service braked vehicles with a gross vehicle weight rating greater than 4500 kg (10 000 lb). The components covered in this document are the primary actuation and the foundation park brake. Various peripheral devices such as application dashboard switches or indicator
7、s are not included. These test procedures include the following: a. Brake Related Tests 1. Brake Functional Performance 2. Brake Dynamic Torque Performance 3. Brake Corrosion Resistance 4. Brake Endurance with Torque 5. Brake Endurance without Torque 6. Vibration Resistance 7. Brake Ultimate Static
8、Load 8. Brake Lining Wear Adjuster Function SAE INTERNATIONAL J2690 OCT2016 Page 2 of 13 b. Actuation Related Tests 1. Mechanical Actuator Functional Performance 2. Mechanical Actuator Endurance 3. Mechanical Actuator Quick Release 4. Mechanical Actuator Ultimate Load 5. Spring Apply Actuator Functi
9、onal Performance 6. Spring Apply Actuator Operating Temperature Range 7. Spring Apply Actuator Endurance 8. Spring Apply Actuator Corrosion Resistance 9. Spring Apply Actuator On-Off Switch 10. Spring Apply Actuator Vibration 1.1 Purpose This document establishes uniform accelerated laboratory test
10、procedures for evaluating comparative performance characteristics of driveline parking brake components. These tests are based upon long standing industry practices. The location of the driveline park brake on the vehicle is generally on the drive axle carrier or transmission assemblies. 2. REFERENC
11、ES 2.1 Applicable Documents The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply. 2.1.1 SAE Publication Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-
12、0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. SAE J79 Brake Disc and Drum Thermocouple Installation 2.1.2 ASTM Publication Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, www.a
13、stm.org. ASTM B 117-97 Standard Practice for Operating Salt Spray (Fog) Apparatus SAE INTERNATIONAL J2690 OCT2016 Page 3 of 13 3. DEFINITIONS 3.1 BRAKE ARM The lever receiving input load from the actuation system. This lever is inside or attached to the driveline mounted brake. See Figure 1. 3.2 PAR
14、KING BRAKE LEVER The lever in the truck cab that is used to apply and release the park brake. See Figure 1. FIGURE 1 - PARK BRAKE SYSTEM DIAGRAM 3.3 ENDURANCE LIFE The total number of applies and releases required for the endurance tests outlined herein. The endurance life requirement is dependent o
15、n vehicle vocation and usage and therefore will be as specified for the application for these tests. A suggested endurance life target is included herein. 4. GENERAL NOTES 4.1 Targets It is important to note that a large range of reasonable test targets exist corresponding to the many and varied veh
16、icle and parking brake customer usage patterns. Users of this specification should adjust the targets to suit their particular applications, particularly for the durability cycles presented in 5.4 and 5.5. The cycle requirements presented in these two sections are offered solely for the sake of havi
17、ng a tangible target, but represent what would be considered the low end of a range of possible test requirements for most medium and heavy truck and bus applications. 4.2 Temperature Unless otherwise specified all testing shall be conducted at an ambient temperature of 15 to 32 C (60 to 90 F). Elec
18、trical Control+ -+-FluidElectrical On/Off SwitchAlternative Spring Apply Actuator+-Electrical On/Off SwitchParking Brake LeverMechanical ActuatorCableDriveline Park BrakeCableCableBrake ArmDrum style park brake showneverSAE INTERNATIONAL J2690 OCT2016 Page 4 of 13 4.3 Mounting All testing shall be c
19、onducted with the brake mounted essentially as intended on the vehicle and in accordance with the manufacturers recommendations. The actual mounting position for each test shall be documented. 4.4 Cycle Rate (Endurance Test) All endurance testing shall be done at a rate of up to 20 cycles per minute
20、. Faster rates are permitted if no abnormal effects (vibration, temperature, noise) are introduced. 4.5 Test Conditions Unless otherwise specified all tests will be conducted in the laboratory and with new components including friction materials and drum/rotor. 4.6 Brake Output Torque Unless specifi
21、ed, the torque values are recorded at the desired brake input loads and in the static (no rotation) condition. 4.7 Brake Input Loads Input loads to be determined based on the application. The load is measured at the brake arm, not the parking brake lever (generally located in the cab) or the spring
22、actuator output (see Figure 1). 4.8 Direction of Applied Torque Is designated as either clockwise or counter-clockwise as viewed from the front of the vehicle toward the rear. 4.9 Tolerance 4.9.1 Torque and force shall be 5% unless otherwise specified. 4.9.2 Temperature shall be 3 C (5 F). 4.10 Spec
23、ific Monitoring of Loads and Travel Due to actual vehicle or system set-up, it is not always practical to monitor all travel and loads at various locations. These locations and necessary system modifications must be tailored to the parking brakes intended application and noted accordingly. 4.11 Test
24、 Samples Recommended quantity for test samples are shown in Table 1. Unless otherwise specified, it is not necessary to use the same brake assembly for more than one test section. SAE INTERNATIONAL J2690 OCT2016 Page 5 of 13TABLE 1 - TEST SAMPLE RECOMMENDED QUANTITY FOR EACH TEST SECTION TEST RECOMM
25、ENDED QUANTITY Brake Related Tests 5.1 Brake Functional Performance 5 5.2 Brake Dynamic Torque Performance 2 5.3 Brake Corrosion Resistance 2 5.4 Brake Endurance with torque 3 5.5 Brake Endurance without torque 3 5.6 Vibration Resistance 2 5.7 Brake Ultimate Static Load 2 5.8 Brake Lining Wear Adjus
26、ter Function 5 Actuation Related Tests 6.1 Mechanical Actuator Functional Performance 5 6.2 Mechanical Actuator Endurance 3 6.3 Mechanical Actuator Quick Release 1 6.4 Mechanical Actuator Ultimate Load 2 6.5 Spring Apply Actuator Functional Performance 5 6.6 Spring Apply Actuator Operating Temperatu
27、re Range 2 6.7 Spring Apply Actuator Endurance 2 6.8 Spring Apply Actuator Corrosion Test 2 6.9 Spring Apply Actuator On-Off switch 2 6.10 Spring Apply Actuator Vibration Test 2 5. BRAKE RELATED TESTS 5.1 Brake Functional Performance 5.1.1 Burnish brake linings per manufacturers recommendations. For
28、 laboratory test purposes, burnishing may be done on a suitable dynamometer, with speed and inertia load as appropriate for the size, axle ratio, wheel diameter, and speed of vehicle under consideration. NOTE: A specially instrumented and calibrated brake arm, or a load cell at the cable input conne
29、ction to the brake arm, may be required to insure correct load into the brake.) 5.1.2 With a brake arm load maintaining system (accuracy 5%) as shown in Figure 2, apply and hold 22 kg (50 lb) brake input force to the brake lever with no torque applied to the brake drum or rotor. FIGURE 2 - BRAKE LEV
30、ER LOAD MAINTAINING SYSTEM Driveline Mounted Brake Drum style shown Force Generator Load CellFeedback Circuit Brake Arm Load Cable or Rod Servo Valve SAE INTERNATIONAL J2690 OCT2016 Page 6 of 13 5.1.3 Apply 56 Nm (500 lb-in) torque to the drum in the clockwise direction (as would be installed facing
31、 rearward from the front of the vehicle). Increase torque at a rate of 113 to 1130 Nm (1000 to 30 000 lb-in) per minute. 5.1.4 Measure the maximum torque achieved before the drum or rotor assembly slides or slips. The slide or slip torque shall be defined as the maximum amount of torque achieved dur
32、ing the first 10 degrees of drum or rotor rotation. 5.1.5 Repeat above with torque applied in the opposite direction. 5.1.6 Repeat above with a brake lever load of 45 kg (100 lb) and up to the maximum parking brake lever load in increments of 23 kg (50 lb). 5.1.7 Record force and torque data. 5.2 Br
33、ake Dynamic Torque Performance 5.2.1 Install brake assembly on a dynamometer to allow the drum or rotor to rotate relative to the brake assembly. Verify clearance between brake and drum (cage clearance) or rotor is per manufacturers recommendation. Install brake such that dynamometer rotational dire
34、ction will be the same as forward direction of the vehicle. 5.2.2 Set dynamometer at appropriate dynamic inertia, or appropriate settings if not an inertia type dynamometer, based on vehicle parameters including weight, tire rolling radius, and axle ratio. 5.2.3 Install thermocouple in the drum or r
35、otor in accordance with Recommended Practice SAE J79 or as agreed upon with the customer. Initial drum or rotor temperature shall be 93 C (200 F) or as otherwise agreed upon with the customer. 5.2.4 With a brake arm load maintaining system (accuracy 5%) as shown in Figure 2, burnish brake per manufa
36、cturers recommendation. Record results including brake arm load and equivalent stop distance during the burnishing process. 5.2.5 At the desired dynamometer rotational speed, apply a 23 kg (50 lb) load to the brake arm. Apply time of the brake shall be less than 1.4 seconds after apply initiation. 5
37、.2.6 Record revolutions to stop the inertia. 5.2.7 Repeat the above in increments of 50 lb brake arm load to the maximum input load desired. 5.2.8 Record brake arm force and equivalent distance to stop the inertia. 5.3 Brake Corrosion Resistance 5.3.1 Functional test each brake assembly and record t
38、he data 5.3.2 Position brake assembly and drum or rotor, or spring apply actuator, in an ASTM B 117 salt spray chamber or equivalent. 5.3.3 Orient components consistent with installation on the vehicle. 5.3.4 Subject components to 5% salt solution per ASTM B 117 for 100 h. 5.3.5 Remove brake assembl
39、y and drum or rotor from salt spray chamber and, within 1 h of removal, cycle the brake at 0 torque and brake arm input force per manufacturer for 100 cycles. SAE INTERNATIONAL J2690 OCT2016 Page 7 of 13 5.3.6 Continue to expose the same brake components for a total of 500 h exposure to the salt spr
40、ay chamber, repeating the above cycling inspection and cycling in 100 h salt spray (fog) increments per 5.3.2 and 5.3.3. After the 500 h salt spray exposure is complete, within 1 h after removal from the corrosion chamber, apply the brake at maximum brake arm load for 48 h minimum, and then release
41、the brake. 5.3.7 Re-test the functional performance of the brake assembly (reference 5.1). 5.4 Brake Endurance with Torque 5.4.1 Functional test each brake assembly and record the data. 5.4.2 Install brake assembly and drum or rotor, per manufacturers recommendations, in a test fixture having the ca
42、pability to control brake arm force and applied drum or rotor torque in each direction. 5.4.3 Applying the appropriate brake arm load as intended for the application, and torque to the drum or rotor as specified below, proceed to subject the brake to the following duty cycle: x 100 000 applies/relea
43、ses x 10 000 in-lb torque each apply x Alternate direction of torque every 5th apply. NOTE 1: Other duty cycles or loading may be more appropriately suited for the brakes intended application. See also 4.1. NOTE 2: During this test, new shoes and linings may be installed at 50 000 cycles or above. N
44、OTE 3: If other components loose functionality during the test, replace as necessary and document the change. NOTE 4: The application components such as the apply cable are not subject to cycle life recommendations during this test due to the variability in routing of the cable and the cable life se
45、nsitivity to bend radii. 5.4.4 After the brake dynamic endurance test is complete, test the functional performance of the brake assembly and drum or rotor. 5.4.5 Visually inspect brake assembly and components. 5.5 Brake Endurance without Torque 5.5.1 Functional test each brake assembly and record th
46、e data. 5.5.2 Install brake assembly and drum or rotor, per manufacturers recommendations, in a test fixture having the capability to control brake arm force. This test will not simulate torque. 5.5.3 Apply the appropriate brake arm load as intended for the application as specified below. Proceed to
47、 subject the brake to the following duty cycle: x 500 000 applies/releases x Loading apply a load that would be required to obtain the torque outlined in 5.4.2 SAE INTERNATIONAL J2690 OCT2016 Page 8 of 13 NOTE 1: Other duty cycles or load may be used as appropriate for the brakes intended applicatio
48、n. See also 4.1. NOTE 2: If other components loose functionality during the test, replace as necessary and document the change. NOTE 3: The application components such as the apply cable are not subject to cycle life recommendations during this test due to the variability in routing of the cable and
49、 the cable life sensitivity to bend radii. 5.5.4 After the brake dynamic endurance test is complete, test the functional performance of the brake assembly. 5.5.5 Visually inspect brake assembly and components. 5.6 Vibration Resistance 5.6.1 Install brake assembly and drum or rotor on vibration machine in orientation consistent with the vehicle application. 5.6.2 For brakes mounted on the vehicle axle or t
