SAEJ903cv001

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 therefrom, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. QUESTIONS REGARDING THIS DOCUMENT: (412) 772-8512 FAX: (412) 776-0243 TO PLACE A DOCUMENT ORDER; (412) 776-4970 FAX: (412) 776-0790 Copyright 1973 Society of Automotive Engineers, Inc. All rights reserved. Printed in U.S.A. SURFACE VEHICLE 400 Commonwealth Drive, Warrendale, PA 15096-0001 RECOMMENDED PRACTICE Submitted for recognition as an American National Standard J903c REV. NOV73 Issued 1964-08 Revised 1973-11 Superseding J903c AUG64 PASSENGER CAR WINDSHIELD WIPER SYSTEMS Foreword—This Document has not changed other than to put it into the new SAE Technical Standards Board Format. 1. Scope—The scope of this SAE Recommended Practice is to establish uniform test procedures and minimum performance criteria for passenger car windshield wiping systems and wiper blades. This recommended practice provides a uniform terminology of windshield wiper system characteristics and phenomena. Also included are guides for the use of engineering layout studies to evaluate system wiped area performance. The test procedures are limited to those tests that can be conducted on uniform test equipment by commercially available laboratory facilities. The test procedures and minimum performance criteria outlined in this recommended practice are based on currently available engineering data. It is the intent that all portions of the recommended practice will be periodically reviewed and revised as additional data regarding windshield wiping system performance are developed. 2. References 2.1 Applicable Publications—The following publications form a part of the specification to the extent specified herein. Unless otherwise indicated the latest revision of SAE publications shall apply. 2.1.1 SAE PUBLICATION—Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001. SAE J941—Motor Vehicle Drivers' Eye Location 2.1.2 ASTM PUBLICATIONS—Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959. ASTM D 518—Method of Test for Resistance to Surface Cracking of Stretched Rubber Compounds ASTM D 1171—Method of Test for Weather Resistance to Exposure of Automotive Rubber Compounds 3. Definitions 3.1 Windshield Wiper System—The wiper system consists of all the apparatus for cleaning the exterior surface of windshield glazing, together with the necessary devices and controls to actuate and arrest the operations. 3.2 Windshield Wiper Blade—A device for cleaning the effective wipe pattern, capable of receiving pressure from an arm, comprising a suitable superstructure, and supporting and controlling a wiper blade element. SAE J903c Revised NOV73 -2- 3.3 Wiper Blade Element—The resilient member of the wiper blade that contacts the windshield glazing surface. 3.4 Wiped Area—The specific area on the windshield glazing surface which shall be covered by the effective wiper pattern. These areas were developed as being compatible with viewing requirements necessary to operate a passenger car vehicle. 3.5 Eyellipse—A statistical representation of the driver's eye location in a motor vehicle, as defined in SAE J941. For the purpose of this recommended practice, the head turn consideration in SAE J941 will not be used. For individual-type passenger car seats, use paragraph 2.2 of the Appendix in SAE J941. 3.6 Effective Wipe Pattern—That portion of the wet windshield glazing surface which is cleared when the wiper blade travels through a cycle with system on highest frequency. 3.7 Tandem Pattern—The pattern produced by the wiper blades moving in the same direction across the windshield glazing surface simultaneously. 3.8 Opposed Pattern—The pattern produced by the wiper blades moving in opposite directions across the windshield glazing surface simultaneously. 3.9 Chatter—Irregular movement of the wiper blade usually accompanied by temporary visible radial lines and/or noise. 3.10 Ballooning—Unwiped areas within the wiper pattern, varying in size and usually round. 3.11 Streaking—Fine arcuate lines of unwiped moisture within the wipe pattern. 3.12 Scalloping—Uneven wipe at the outer periphery of pattern. 3.13 Lace Curtain—A maze of fine individual water droplets which are formed after the wiper blade passes over the windshield glazing surface. 3.14 Hazing—An aerated film spread by the blade and resulting in a transient trailing band on the windshield glazing surface. 3.15 Cycle—A cycle shall consist of wiper blade movement during system operation from one extreme of the windshield wipe pattern to the other extreme and return. 3.16 Snow Load—The load imposed on the wiper system by the accumulation of packed snow, resulting in a limitation of blade travel. 3.17 Motor Stall Torque—The maximum torque that the motor can maintain for two cycles at specified conditions. 3.18 System Torque—Torque necessary to overcome maximum friction of the wiper blade and the driving mechanism under specified conditions. 3.19 Damp Dry—The condition of the windshield which produces the highest friction during the transition from a wet to a dry surface. 3.20 Moisture—Atmospheric water precipitation in liquid, semi-liquid, or frozen state (snow). 3.21 Relative Air Speed—The vector difference of vehicle speed and the component of the wind speed parallel to the direction of travel of the vehicle. SAE J903c Revised NOV73 -3- 3.22 Daylight Opening (DLO)—The term "daylight opening" (DLO) refers to the maximum unobstructed opening through any glass aperature, with reveal or garnish moldings adjoining the glazing surface installed normal to the glass surface. 4. General Performance 4.1 Windshield Wiper System 4.1.1 WIPED AREA—The minimum windshield wiped area is described by three specific areas on the exterior windshield glazing surface. The three areas are developed with the vehicle loaded to the manufacturer's base design load and are identified in Table 1 as areas A, B, and C. Each area has been established using the angles of Table 1 applied as shown in Figure 1. In the side view, the upper and lower boundary of the area is established by the intersection of two planes, which are seen as lines tangent to the upper and lower edges of the eyellipse, with the windshield glazing surface. The planes are fixed by angles above and below the XX line. In the plan view, the left and right boundary of the area is established by the intersection of two vertical planes tangent to the left and right edges of the eyellipse with the windshield glazing surface. The planes are fixed by angles to the left and right of the XX line. The areas used in determining the percentage of wiped area are those areas on the exterior glazing surface which are not within 1 in. (25 mm) of the edge of the daylight opening (pillars, division bar, header, etc.). The percentage is the ratio of wiped area within the defined area to the defined area. Using test procedures established in paragraph 5.1, Table 1 for percentages 'to be wiped.' 4.1.2 FREQUENCY—The windshield wiper system shall be designed to provide two or more frequencies. One of the frequencies shall be a minimum of 45 cycles/min. The highest and one lower frequency shall differ by at least 15 cycles/min. Such lower frequency shall be at least 20 cycles/min. These frequencies must be obtainable under normal vehicle operating conditions regardless of engine speed and engine load, following test procedures and test conditions established in 5.2. 4.1.3 DURABILITY—Wiping system, except for the wipe blade element, must remain functional after operating 1 500 000 cycles, using test procedure and test conditions established in 5.2. 4.1.4 STRENGTH—The system shall be capable of withstanding the loads induced by stall, using test conditions and test procedures established in 5.3, with all mechanical components remaining functional. 4.1.5 TEMPERATURE OPERATIONAL CAPABILITY—The windshield wiper system shall be capable of operating between temperatures of 130 ± 5 °F (35 ± 3 °C) and -20 ± 5 °F (-30 ±5 °C), using test procedures and test conditions established in 5.4. 4.1.6 ACCESSIBILITY—The control for the wiper system should be positioned so that it is readily accessible to the driver. TABLE 1—AREA TO BE WIPED Area Min Per cent Wiped Angles, deg Left Angles, deg Right Angles, deg Up Angles,deg Down A 80 18 56 10 5 B 95 14 53 5 3 C 100 10 15 5 1 SAE J903c Revised NOV73 -4- FIGURE 1—EYELLIPSE TEMPLATE LOCATION 4.2 Windshield Wiper Blade 4.2.1 DURABILITY—Using test procedures and test conditions described in 5.2, the windshield wiper blade, except for the wiper blade element, shall remain functional after operating 1 500 000 cycles and the wiper blade element shall wipe 75% of the effective wipe pattern after 500 000 cycles. 4.2.2 AGING—The wiper blade element of the wiper blade assembly shall withstand the ozone test established in 5.5 with an ASTM rating of two or better, as defined in ASTM D 1171, Method of Test for Weather Resistance Exposure of Automotive Rubber Compounds. 4.2.3 CHEMICAL RESISTANCE—A section of the wiper blade element when placed in a 50% solution of either methyl or isopropyl alcohol for a period of 24 h shall not exceed more than 2% weight change. SAE J903c Revised NOV73 -5- 5. Test Methods 5.1 Area to be Wiped Test Procedure 5.1.1 TEST EQUIPMENT a. Drafting equipment sufficient for full-size windshield and wiper system layout. b. Transparent heavy gage plastic sheet—Prepared clear acetate or equivalent. c. Test buck—A test buck shall consist of a structure capable of maintaining, throughout the test, the proper relationship of the glazing surface and the windshield wiping system components as established by the vehicle manufacturer. d. Power source—The power source shall supply to the wiper motor the maximum power expected by the vehicle manufacturer under the conditions specified in any of the test procedure paragraphs. e. Spray equipment—Spray nozzles to apply water to glazing surface. 5.1.2 TEST PROCEDURE 5.1.2.1 Drafting a. Work to exterior surface of windshield glazing. b. The design wipe pattern will be shown plus the growth due to wet windshield and high-speed system operation. This growth may be determined experimentally or an assumed allowance for each direction of wipe may be utilized. c. All calculations shall be made in the unwrapped view. d. In vehicle position plan view and side view, layout windshield surface, DLO (daylight opening), 95th percentile eyellipse per SAE J941, and the areas A, B, and C, generated on the exterior of the windshield glazing surface using the angles from Table 1. e. Develop an unwrapped view of the windshield glazing surface and DLO. Design the wipe pattern, apply growth as described in 5.1.2.1(b), and transfer the pattern together with areas A, B, and C into this unwrapped view. f. Calculate the percentages of areas A, B, and C that are wiped with design pattern plus growth, in the unwrapped view. See Figure 2 and compare the values with those of Table 1. FIGURE 2—WIPED AREA EVALUATION, DRAFTING TEST PROCEDURE— UNWRAPPED VIEW SHOWING WIPED PATTERN AND AREAS A, B, AND C SAE J903c Revised NOV73 -6- 5.1.2.2 Test Buck Evaluation a. Operate test buck with water on and wiper system on high speed, and mark outline of wipe pattern. b. Transfer full-size unwrapped view with wipe pattern and areas A, B, and C as determined in 5.1.2.1(e) to transparent heavy gage plastic sheet. c. Transfer wipe pattern from the test buck to the plastic sheet and recalculate the percentages of areas A, B, and C that are wiped and compare the values with those of Table 1. 5.2 Wiper System Durability and Frequency Test 5.2.1 TEST EQUIPMENT—AS REQUIRED a. Test buck—See 5.1.1(c). b. Power source—See 5.1.1(d). c. Counters—A device for determining the number of cycles. d. Spray equipment—See 5.1.1(e). e. Water softener—A device, where required, to supply water meeting requirements of 5.2.2(d). f. Cleanser—Of a nonabrasive type. g. Temperature measuring device—Thermometer or equivalent. h. Voltmeter. i. Vacuum gage. j. Hydraulic pressure gage. 5.2.2 TEST CONDITIONS a. Ambient temperature of 50–100 °F (10–38 °C). b. Water temperature of 45–75 °F (7–24 °C). c. Water nozzles—To be located so as to provide an approximately equally distributed water flow on windshield glazing surface at a rate of no less than 50 in.3/min (820 cm3/min). d. Water hardness—Not to exceed 12 grains/gal (0.2 kg/m3). e. Power input level at drive motor (frequency test only)—The minimum power available at the drive motor, as specified by the vehicle manufacturer, under normal vehicle operating conditions. 5.2.3 FREQUENCY TEST PROCEDURE—Clean the windshield. Water is to be applied continuously to the windshield throughout the test, as indicated in paragraph 5.2.2(c). Apply power to the drive motor as specified in paragraph 5.2.2(e). With appropriate control settings, determine system operating frequencies. 5.2.4 DURABILITY TEST PROCEDURE—The windshield wiper system shall be operated for 1 500 000 cycles, 750 000 cycles at the high-frequency setting and 750 000 cycles at low-frequency setting. In both the high-frequency and low-frequency test cycles, the operational sequence shall be as follows: Wet operation—water on 5 1/2 min. Dry operation—water off 1/2 min. Park position—1 min max. For the wet operation, water is to be supplied to the windshield in accordance with the provisions of 5.2.2(c). The windshield is to be cleaned when necessary. If rubber deposits appear within 15 min after cleaning, the wiper blade element must be replaced. Any component failure, except windshield wiper blade element, during this test denotes system failure. SAE J903c Revised NOV73 -7- 5.3 Wiper System Stall Test 5.3.1 TEST EQUIPMENT a. Test buck—See 5.1.1(c). b. Power source—See 5.1.1(d). 5.3.2 TEST PROCEDURE—Under any normal mode of operation, the wiper system shall meet the requirements specified in 4.1.4 when the wiper arms are restrained from movement for 15 s, using the specified power source. The wiper system shall be tested at each of the following two temperatures: -20 ± 5°F (-30 ± 3°C) and 30 ± 5 °F (-1 ± 3 °C). 5.4 Wiper System Temperature Operation Capability 5.4.1 TEST EQUIPMENT a. General—Test buck, power source, timing device, and other pertinent equipment described in 5.2.1 shall be used in this test. b. Test chamber—A room or chamber large enough to contain the complete test buck and capable of maintaining a temperature of 130 ± 5 °F (55 ± 3 °C) and/or -20 ± 5 °F (-30 ± 3 °C). 5.4.2 HOT TEST PROCEDURE—The test buck and spray equipment are to be soaked in the test chamber at a temperature of 130 ± 5 °F (55 ± 3 °C) for 4 h. Following this soak period and in the same temperature environment, the wiper system and spray equipment are to be turned on and operated for a period of 1/2 h at maximum wiper speed control setting with water applied continuously, as indicated in 5.2.2(c). 5.4.3 COLD TEST PROCEDURE—The test buck is to be soaked in the test chamber at a temperature of -20 ± 5 °F (-30 ± 3 °C) for 4 h. Following this soak period and in the same temperature environment, the wiper system is to be turned on and the wipers operated for 1/2 h at maximum wiper system speed control setting. 5.5 Ozone Testing 5.5.1 EQUIPMENT—Commercial ozone test cabinet. 5.5.2 PREPARATION OF WIPER BLADE ELEMENT—A 6 in. (150 mm) specimen of the wiper blade element of the wiper blade assembly is to be installed in a suitable clamping fixture similar to that described in Procedure A of ASTM D 518, Method of Test for Resistance to Surface Cracking of Stretched Rubber Compounds. Specimens are to be stretched so as to cause an extension of 15% measured between gage marks that are 4 in. (100 mm) apart. The mounted specimens are then to be exposed for 48 h in an ozone-free atmosphere. 5.5.3 PROCEDURE—Test specimens are to be placed in the ozone test chamber for a period of 72 h. The test chamber is to be operated at a temperature of 100 ± 5 °F (38 ± 3 °C) and at a concentration of 50 pphm, by volume. 5.5.4 RATING—That area of the specimen between the two bench marks shall meet the requirements established in 4.2.2. 6. Notes 6.1 Marginal Indicia—The change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions have been made to the previous issue of the report. An (R) symbol to the left of the document title indicates a complete revision of the report. PREPARED BY THE SAE BODY ENGINEERING COMMITTEE SAE J903c Revised NOV73 Rationale—Not applicable. Relationship of SAE Standard to ISO Standard—Not applicable. Application—The scope of this SAE Recommended Practice is to establish uniform test procedures and minimum performance criteria for passenger car windshield wiping systems and wiper blades. This recommended practice provides a uniform terminology of windshield wiper system characteristics and phenomena. Also included are guides for the use of engineering layout studies to evaluate system wiped area performance. The test procedures are limited to those tests that can be conducted on uniform test equipment by commercially available laboratory facilities. The test procedures and minimum performance criteria outlined in this recommended practice are based on currently available engineering data. It is the intent that all portions of the recommended practice will be periodically reviewed and revised as additional data regarding windshield wiping system performance are developed. Reference Section SAE J941—Motor Vehicle Drivers' Eye Location ASTM D 518—Method of Test for Resistance to Surface Cracking of Stretched Rubber Compounds ASTM D 1171—Method of Test for Weather Resistance to Exposure of Automotive Rubber Compounds Developed by the SAE Body Engineering Committee