1、 WORLDWIDE ENGINEERING STANDARDS Test Procedure GMW14957 FMVSS 202a Dimensional and Static Performance Testing for Head Restraints Copyright 2011 General Motors Company All Rights Reserved November 2011 Originating Department: North American Engineering Standards Page 1 of 16 1 Scope Note: Nothing i
2、n this standard supercedes applicable laws and regulations. Note: In the event of conflict between the English and domestic language, the English language shall take precedence. 1.1 Purpose. The purpose of this test procedure is to determine if a head restraint/seat system meet(s) the dimensional an
3、d static requirements of FMVSS 202a. 1.2 Foreword. Head restraints are subjected to strikes simulating the head impact in the case of an accident, as well as dimensional criteria for height, width, set back and strength of the head restraint to minimize the rotation of the head relative to the torso
4、. The intent is to improve occupant protection and reduce the frequency and severity of neck injury in rear-end and other collisions. Occupant impact protection must be addressed during the design stages of vehicle development. It is expected that early in the design stage that dimensional layouts h
5、ave been conducted and that analysis has been completed to ensure the success of the testing. This procedure describes the method for testing the seat outside of the vehicle, however, in some instances the vehicle or portions of it may be required. All values given in this test procedure were valid
6、at the date of issue. For the actual values refer to the newest editions of the standards mentioned in 2.1. 1.3 Applicability. This standard applies to each front outboard designated seating position and each applicable rear outboard designated seating position with a head restraint. 2 References No
7、te: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. 49 CFR 571.202a FMVSS 202a 49 CFR Part 572 SAE J826 2.2 GM Standards/Specifications. GMW14606 2.3 Additional References. Seat System Subsystem Technical Specification (SSTS) 3 Res
8、ources 3.1 Facilities. Organization for International Standards (ISO) certified lab facility. 3.2 Equipment. 3.2.1 SAE J826 Three Dimensional (3D) manikin, Edition 95. Thigh = 10%, Leg = 50%. 3.2.2 Sphere Diameter: 25 0.25 mm. 3.2.3 Steel Tape with accuracy of 0.75 mm and sufficient range for measur
9、ing the height of the head restraint. 3.2.4 Carpenters Square. 3.2.5 Calipers with accuracy of 0.75 mm. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERIN
10、G STANDARDS GMW14957 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 2 of 16 3.2.6 Head Restraint Measurement Device (HRMD). The SAE J826 three-dimensional manikin with a head form attached. 3.2.7 Spherical head form with a 165 2 mm diameter with surface roughness less t
11、han 1.6 m, root mean square. 3.2.8 Inclinometer with accuracy of 0.2 mm degrees. 3.2.9 Fifth (5th) percentile female HIII 49 CFR Part 572 (non-instrumented). 3.2.10 A cylindrical test device or device having a 165 2 mm diameter in plane view (perpendicular to the axis of revolution) and a 152 mm len
12、gth in profile (through the axis of revolution) with a surface roughness of less than 1.6 m root mean square (height retention test). 3.2.11 A load application device capable of applying a force up to 890 N with a precision of 1 N and at variable rate. 3.2.12 A test device having the back pan dimens
13、ions and torso reference line vertical centerline, when viewed laterally, with the head room probe in the full back position of the three dimensional SAE J826 manikin (for backset retention and displacement). 3.2.13 Additional Equipment for Energy Absorption Testing. 3.2.13.1 Test stand and fixture
14、setup to retain test vehicle and other test equipment needed to conduct head restraint test. 3.2.13.2 Semispherical head form of mass 6.8 0.05 kg, with a 165 2 mm diameter with surface roughness less than 1.6 m, root mean square and capable of attaching to a propulsion device. The impactor shall be
15、instrumented with an accelerometer having the axis coincident with the geometric center of the head form and the direction of impact. 3.2.13.3 Propulsion device capable of propelling the semispherical head form and its base at 23.6 0.5 kph, and maintaining the impactor trajectory within 2 degrees of
16、 horizontal and parallel to the vehicle longitudinal axis for at least a travel distance of 25 mm. 3.3 Test Vehicle/Test Piece. A complete trimmed seat subsystem, consisting of all components necessary to qualify as complete for the model and trim level specified by the Design Release Engineer (DRE)
17、, is required. Testing may be conducted on bed plate. Vehicle may be required when roof prevents the minimum height requirements Typically three (3) seats are required for the following measurements: One seat set for gap, height, width, backset, strength and height retention. One seat set for backse
18、t retention, displacement, and strength. One seat for energy absorption test. 3.4 Test Time. Calendar time: 5 days Test hours: 8 hours Coordination hours: 8 hours 3.5 Test Required Information. Manufacturers drawing showing seat dimensions, arrangement, and Seating Group Reference Point (SGRP). 3.6
19、Personnel/Skills. The following individuals are necessary to complete this test procedure: General Motors Validation Engineer, Testing Organizations Test Engineer, Testing Organizations Test Technician. 4 Procedure 4.1 Preparation. Test plate or vehicle buck and equipment to rigidly affix the seat.
20、4.2 Conditions. 4.2.1 Environmental Conditions. Test to be conducted at ambient temperature. 4.2.2 Test Conditions. Deviations from the requirements of this standard shall have been agreed upon. Such requirements shall be specified on component drawings, test certificates, reports, etc. Copyright Ge
21、neral Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14957 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 3 of 16 4.3 Instru
22、ctions. For the tests described from 4.3.2. thru 4.3.7, demonstrate compliance with any adjustable lumbar support adjusted to its most posterior nominal design position. Negative lumbar adjustment. 4.3.1 Determine H-point for Testing Purposes. 4.3.1.1 If the seat cushion adjusts independently of the
23、 seat back, adjust the seat cushion to the highest achievable H-point and seat back in design position. 4.3.1.2 Position the 3-D mechanical manikin (Figure 1) per SAE J826; record the H-point on Data Sheet A1 (Appendix A) as initial reading. Evaluate to the design SGRP for approximation to highest p
24、oint in travel box. Contact the GM Validation Engineer or GM Lead Engineer if there is more than a 10 mm conflict between these values before completing the remainder of this test. 4.3.1.3 Measure the seat back angle using the back angle quadrant of the manikin. 4.3.1.4 Adjust lumbar and bolster adj
25、ustment to the most non-supportive positions. Adjust the seat back to produce a design torso back angle. If the adjustment is such that that the angle is less than design position then adjust to the next rearward position. 4.3.1.5 Record this H-point and the seat back angle on Data Sheet A1 (Appendi
26、x A) as test H-point and seat angle. Note: This H-point and seat back angle are maintained throughout the testing. Figure 1: H-Point and Height Measurements 4.3.2. Measurements for Height and Width. 4.3.2.1 Height Measurement. 4.3.2.1.1 Adjust the head restraint to the highest adjustable position. E
27、xtend the head probe along a line parallel to the torso reference line to record the height of the top of the head restraint. Ensure the positioning of the manikin to the H-point obtained in 4.3.2. If the head probe cannot be extended due to interference, then Copyright General Motors Company Provid
28、ed by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14957 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 4 of 16 measure the height along a line paral
29、lel to the torso reference line (Figure 2). Record this as the upper height on Data Sheet A1 (Appendix A). 4.3.2.1.2 The height must be equal to, or larger than 800 mm for front outboard seat and 750 mm for rear seat outboard positions, except where the roof of the vehicle prevents the head restrain
30、t from reaching the required height. If this occurs, the head restraint must be measured in vehicle and be sufficient enough in height to prevent a 25 mm diameter sphere from passing between the top of the head restraint and the roof. 4.3.2.1.3 An additional exception for a rear outboard designated
31、seating position exists, in that a head restraint is not required if the height measurement is less than 700 mm when measured at the centerline of the seat back or the head restraint-like device. Record this height on Data Sheet A1 (Appendix A), no further measurements are required. 4.3.2.1.4 Adjust
32、 the head restraint to the lowest adjustable position. Again measure the height along the torso reference line and record as lower height on Data Sheet A1 (Appendix A). Figure 2: Height Measurements 4.3.2.2 Width Measurement. 4.3.2.2.1 Measure the width of the head restraint at a distance 65 3 mm be
33、low the top of the head restraint and perpendicular to the torso reference line. The minimum width from centerline for either side of head restraint must be 85 mm for 170 mm minimum (254 mm for front seats requiring the wider head restraints, for example, outboard front seats when a center front des
34、ign seating position exists). Record this as the width on Data Sheet A1 (Appendix A). 4.3.2.2.2 Removability of Head Restraints. Verify that that the action to remove the head restraint is a separate action from the sequence of adjusting the head restraint. Record on Data Sheet A1 (Appendix A). 4.3.
35、3 Backset Measurement. Copyright General Motors Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14957 Copyright 2011 General Motors Company All Rights Reserved No
36、vember 2011 Page 5 of 16 4.3.3.1 Remove the SAE manikin torso weights. 4.3.3.2 For adjustable head restraints, adjust the head restraint to the largest backset dimension attainable to the head form at height adjustments between 750 mm and 800 mm; if no position exists below 800 mm, adjust to lowest
37、position available. If the head restraint tilts fore and aft, adjust to the rearmost position. For integral or fixed head restraint, measure largest backset dimension between 750 mm and 800 mm height. 4.3.3.3 Attach the 6 torso weights, attaching the two larger weights flat side down last. Attach th
38、e remaining four weights by alternating side to side. Weights should be supplied with the HRMD. 4.3.3.4 Attach the HRMD head form and level it by loosening the rear knob and bubble level. 4.3.3.5 Measure the Torso. If the torso angle is not in design position 1 degree, remove the buttocks and torso
39、weights, re-adjust the back angle and repeat the four previous steps until a torso angle of design position 1 degrees is obtained and the head probe is within 15 mm of the head restraint centerline. 4.3.3.6 Push the central probe toward the head restraint until the probe profile touches the A surfac
40、e as shown in Figure 3. 4.3.3.7 Record the measurement on Data Sheet A1 (Appendix A) as backset measurement. 4.3.3.8 The measured backset shall be less than or equal to 55 mm. Figure 3: Head Restraint Measurement Device 4.3.4 Gap Measurement. 4.3.4.1 If the head restraint is adjustable, adjust the h
41、ead restraint to the lowest adjustable position and any backset position. 4.3.4.2 Check the torso angle and location of the head probe relative to the centerline of the restraint. Adjust the seat if necessary (Figure 4). Copyright General Motors Company Provided by IHS under license with General Mot
42、ors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14957 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 6 of 16 Figure 4: Gap Measurement 4.3.4.3 Determine Area of Measurement. 4.3.4.3.1 Ex
43、tend the head probe along a parallel line to the torso reference line until 540 mm is achieved. Project a perpendicular plane to the torso line and mark the line that represents the intersection of the plane and the seat back. 4.3.4.3.2 For seats required to have 170 mm head restraint width, measure
44、 85 mm from the seat back centerline and draw a line on each side. For seats required to have 254 mm head restraint width, measure 127 mm form the seat back centerline and draw a parallel line on each. Record this on Data Sheet A1 (Appendix A) with a sketch showing where measurements were taken. 4.3
45、.4.4 Determine Gap Dimension. 4.3.4.4.1 Using calipers, measure the largest gaps in the area comprised by the lines described in 4.3.4.3.1 and 4.3.4.3.2, on the seat back, head restraint, and between seat back and head restraint as shown in gap measurement (Figure 5). For gaps measuring more than 50
46、 mm, use the 165 spherical head form with a transferable medium to mark the points of contact. Do not exceed a force of 5 N when placing the head form against a gap. Measure the straight line distance between the two furthest points and show on sketch and record measurement. Copyright General Motors
47、 Company Provided by IHS under license with General Motors CompanyNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-GM WORLDWIDE ENGINEERING STANDARDS GMW14957 Copyright 2011 General Motors Company All Rights Reserved November 2011 Page 7 of 16 Figure 5: Gap Measurem
48、ent 4.3.4.4.1.1 Method Using a 165 mm Sphere Head Restraints Design. Measure the largest gaps in the area comprised by the lines described in 4.3.4.3.1 and 4.3.4.3.2, on the seat back, head restraint, and between seat back and head restraint as shown in gap measurement. For gaps measuring more than
49、50 mm, use the 165 spherical head form with a transferable medium to mark the points of contact (Figure 6). Do not exceed a force of 5 N when placing the head form against a gap. Measure the straight line distance between the two furthest points and show on sketch and record measurement. Figure 6: Locating the Gap Boundary 165 mm Sphere 4.3.4.4.2 The gaps in the bound
