1、SURFACE VEHICLERECOMMENDED PRACTICEJ1222 AUG2014Issued 1981-02Revised 2014-08Superseding J1222 MAR2012Speed Control Assurance for SnowmobilesRATIONALEUpdates to starting section, and combined normal & unmanned snowmobile test sections to align standard with current snowmobile technology.1. SCOPEThis
2、 SAE Recommended Practice provides minimum requirements and performance criteria for devices to prevent runaway snowmobiles due to malfunction of the speed control system.2. REFERENCES2.1 Applicable DocumentsThe following publications form a part of this specification to the extent specified herein.
3、 Unless otherwise indicated, the latest issue of SAE publications shall apply.2.1.1 SAE PublicationAvailable from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org.SAE J33 Snowmobile Definitions
4、and Nomenclature - General3. DEFINITIONS3.1 SNOWMOBILEAs defined in SAE Recommended Practice J33.3.2 RUNAWAY PREVENTION DEVICEA device, of any type, used to automatically prevent undesirable motion of a snowmobile caused by malfunction or maladjustment of the speed control system._SAE Technical Stan
5、dards 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 re
6、sponsibility 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 2014 SAE InternationalAll rights reserved. No part of this publication may be repro
7、duced, 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: +1 724-776-4970 (outside USA)Fax: 724-7
8、76-0790Email: CustomerServicesae.orgSAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedbackon this Technical Report, please visithttp:/www.sae.org/technical/standards/J1222_201408SAE INTERNATIONAL J1222 Revised AUG2014 Page 2 of 43.3 THROTTLE CONTROLA hand-controlled device moun
9、ted on the steering control, either a lever type (squeeze grip) or a twist-grip type.3.4 SPEED CONTROLLERDevices such as carburetors, fuel injection valves, throttle bodies, etc., used to control the supply of energy (i.e., fuel, spark, etc.) to the prime mover (engine-motor).3.5 SPEED CONTROL SYSTE
10、MA complete system used to control engine speed. This includes the throttle control and its means to activate the speed controller, whether it is control linkage, control cable assembly, springs, & brackets or an electronic drive by wire system. Any attachment to the system that affects its operatio
11、n, such as a warning light switch, safety switch, etc., shall be considered as part of the speed control system.3.6 Tether SwitchA tether switch is an engine shutoff switch that is attached to the operator by the means of a cord between the operator and switch. The switch is activated by separation
12、of tether cord from the tether switch.4. REQUIREMENT OF RUNAWAY PREVENTION DEVICE4.1 Engine StartingThe runaway prevention device, when tested in accordance with 5.2, shall automatically prevent the vehicle from starting or moving at any speed controller position.4.2 Normal & Unmanned Snowmobile Ope
13、rationThe runaway prevention device, when tested in accordance with 5.3, shall automatically interrupt power to the track(s) on removal of operators force from the throttle control with or without driver separation from the vehicle.5. TEST PROCEDURE5.1 Test Equipment and InstrumentationAn instrument
14、 to measure snowmobile ground speed of the track(s) with an accuracy of 10%A means to support the rear of the snowmobile off the ground which will allow the track(s) to turn freely5.1.1 A device or means of simulating the effects of malfunctions of the speed control systems, such that when the opera
15、tor force to actuate the throttle control is released, it will not let the engine return to idle. Malfunctions examined will include speed controller mechanism binding or sticking that will not allow the speed controller to return to its idle position.5.1.1.1 Malfunction of the speed controller shal
16、l be accomplished by blocking the butterfly, slide, etc. in a position that simulates a malfunctioning condition or5.1.1.2 Malfunction of the throttle control or control cable assembly shall be accomplished by fixing the cable in a position that simulates a wide open condition.NOTE: It is suggested
17、that all likely malfunctions be tested and documented.NOTE: With the skis resting on a flat surface, track coasting is acceptable if power is so low that the track will not continue moving when lowered to a ground surface.SAE INTERNATIONAL J1222 Revised AUG2014 Page 3 of 45.1.2 Safety WarningThe tes
18、ts described in 5.2 and 5.3 are hazardous and need to be made by personnel skilled in testing snowmobiles. Safety protection devices shall be used as required.5.2 Starting Test5.2.1 Support the rear of the snowmobile off the ground so the track(s) may rotate and restrain the vehicle to preventpotent
19、ial runaway event.5.2.2 Verify that the snowmobile is properly set up for normal operation and start engine using manufacturersrecommended starting procedure.5.2.3 Advance the snowmobile speed controller to obtain a steady track speed greater than 16 km/h (10 mph). Retainthe speed controller at this
20、 position by the means provided in 5.1.1.5.2.4 Stop the engine 5.2.5 Attempt to start the engine and verify that:5.2.5.1 The engine will not start or if it does5.2.5.2 Power is not applied to the track(s).NOTE: With the skis resting on a flat surface, track coasting is acceptable if power is so low
21、that the track will not continue moving when lowered to a ground surface.NOTE: Limp home mode (LHM) provides a mechanism to operate the vehicle at reduced engine power when a failure is detected in the speed controller system. Ensure limp home mode is not engaged during starting test.5.3 Test for No
22、rmal Operation & Unmanned Operation5.3.1 Verify that the snowmobile is properly set up for normal operation.5.3.2 Support the rear of the snowmobile off the ground so the track(s) may rotate freely, and start the engine.5.3.3 Operate the snowmobile throttle control through its full range of operatio
23、n and verify that the snowmobile drive train is functioning properly.5.3.4 Operate the snowmobile to achieve a speed of 48 km/h (30 mph) then install the device described in 5.1.1 which will retain the speed controller in the 48 km/h (30 mph) speed position. 5.3.5 Remove the operators force from the
24、 throttle control or separate tether cord if so equipped from tether switch and verify that:5.3.6 The power to the track(s) is automatically interrupted. The method used to verify the power to the track(s) has been interrupted shall be documented.NOTE: With the skis resting on a flat surface, track
25、coasting is acceptable if power is so low that the track will not continue moving when lowered to a ground surface. NOTE: Limp home mode (LHM) provides a mechanism to operate the vehicle at reduced engine power when a failure is detected in the speed control system. Ensure limp home mode is not enga
26、ged during starting test. SAE INTERNATIONAL J1222 Revised AUG2014 Page 4 of 46. NOTES6.1 Marginal IndiciaA change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only.PREPARED BY THE SAE SNOWMOBILE TECHNICAL COMMITTEE
