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 entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, 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.Copyright 2008 SAE InternationalAll rights reserved. No part of this publication may be
3、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: 724-776-4970 (outside USA)Fax: 724-
4、776-0790Email: CustomerServicesae.orgSAE WEB ADDRESS: http:/www.sae.orgSURFACEVEHICLESTANDARDJ1790REAF.MAY2008Issued 1998-06Reaffirmed 2008-05Superseding J1790 MAY2003Self-Propelled Sweepers and Scrubbers Steering RequirementsSingle-Circuit Hydraulic Servo-Assisted Systems1. ScopeThe SAE Standard ap
5、plies to self-propelled, driver-operated sweepers and scrubbers as defined inSAE J2130.1.1 PurposeThe purpose of this document is to establish the minimum requirements for a steering mechanismthat is of a single-circuit hydraulic servo-assisted system without any mechanical linkage to the road wheel
6、s,as typically depicted in Figure 1.FIGURE 1GENERAL LAYOUT OF SYSTEMCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1790 Reaffirmed MAY2008-2-2. References2.1 Applicable PublicationThe following
7、 publication forms a part of the specification to the extent specifiedherein. Unless otherwise indicated, the latest revision of SAE publications shall apply.2.1.1 SAE PUBLICATIONAvailable from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.SAE J2130Self-Propelled Sweepers2.2 Related Publica
8、tionsThe following publications are provided for information purposes only and are not arequired part of this document.2.2.1 SAE PUBLICATIONAvailable from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.SAE J1511/ISO 5010:1994Steering for Off-Road Rubber-Tired Machines2.2.2 ISO PUBLICATIONSAv
9、ailable from ANSI, 25 West 43rd Street, New York, NY 10036-8002.ISO 789-11:1996Agricultural tractorsTest proceduresPart 11: Steering capability of wheeled tractorsISO 5010:1992Earth-moving machineryRubber-tired machinesSteering requirementsISO 10998:1995Agricultural wheeled tractorsSteering requirem
10、ents3. Definitions3.1 Steering MechanismAll equipment needed to steer the machine.3.2 Hydraulic Servo-Assisted SystemA system that meters a pressurized flow of fluid from an energy source(e.g., pump) to a steering device (e.g., cylinder) that is linked to the steered road wheels. The metered fluidou
11、tput will also be proportional to the movement of a steering control (e.g., wheel). Additionally, the system willbe able to pump fluid to the steering device by manual effort in the event of failure of the fluid power energysource.3.3 Steering WheelType of steering control that is generally round an
12、d alters the direction of movement byrotary motion.3.4 Steered Road Wheels3.4.1 Wheels, the alignment of which may be altered in relation to the machine in order to obtain a change in thedirection of movement of the machine.3.4.2 All wheels of an articulated machine.3.5 Fluid Power Energy SourceA hy
13、draulic pump means to power the steering system. The pump may bearranged to serve only the steering system (dedicated) or arranged to serve not only the steering system butother hydraulic duties as well (shared).3.6 Single CircuitA hydraulic circuit where there is only one fluid power energy source
14、and one pressureconduit from it to the metering control unit as depicted in Figure 1.3.7 Steering DeviceA fluid power cylinder or actuator that is mechanically linked to the steered road wheels inorder to alter the direction of movement.Copyright SAE International Provided by IHS under license with
15、SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1790 Reaffirmed MAY2008-3-3.8 Turning RadiusRadius of the circular path described by the center of tire contact with the surface of the testsite of the wheel describing the largest circle.3.9 Non ReactiveA sys
16、tem where there is no feed-back from the steering function.3.10 ReactiveA system where feed-back from the steering function may be felt in the steering wheel.4. Special Requirements4.1 The steering wheel shall be easy to use and grip. It shall be designed in such a way as to permit gradualdeflection
17、. The direction of movement of the top of the steering wheel shall correspond to the desired changein the direction of the machine.4.2 Steering wheel play or lash within the steering control unit shall not exceed 8 degrees from the neutral positionto a position where perceptible road wheel movement
18、is observed.4.3 With the fluid power energy source inert, rotary motion of the steering wheel under the influence of manualeffort shall alter the direction of machine movement by supplying a metered supply of pressurized fluid to thesteering device.4.4 One or more pressure limitation devices shall p
19、rotect the whole or parts of the fluid power circuit againstexcess pressure. At all times, protection shall be afforded to individual components and conduits.4.5 The burst pressure ratings of fluid conduits shall be four (4) times the maximum operating pressure permittedby the pressure limitation de
20、vices. The fluid conduits shall be protected and arranged in such a way that risksfrom damage by impact or interference are reduced to a minimum.4.6 The fluid power energy source shall be active whenever the machines prime mover power source is active.4.7 For vehicles with speeds greater than 20 km/
21、h, a warning device shall be provided to indicate a failure of thefluid power energy source, e.g., loss of fluid and/or pressure loss. The device shall be audible or visual or both.In the case of a common reservoir being used to serve the steering pump and other hydraulic services, a low-pressure wa
22、rning device shall be installed to indicate pressure loss in the event of a failure. This warningdevice shall also be applied in the case of the steering pump performing other hydraulic duties as in a sharedsystem.4.8 In systems where the steering pump performs other hydraulic duties as in a shared
23、system as well as steering,priority shall be given to the steering system.5. Performance Requirements5.1 Steering ControlThe steering system may be of the following stylesa. Non-reactive system, preventing external shock forces reacting in the steering system to move thesteering wheelb. Reactive sys
24、tem allowing shock forces to react in the steering system.Both circuit system are shown typically in Figure 2.NOTEIn the cases of reactive systems, the displacement of the steering device shall be equal in eachdirection, shown typically in Figure 2.Copyright SAE International Provided by IHS under l
25、icense with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1790 Reaffirmed MAY2008-4-FIGURE 2REACTIVE AND NON-REACTIVE SYSTEMS5.2 Steering EffortThe machine, from a straight ahead direction, shall be able to execute a steering maneuverwhen negotiating the
26、test course shown in the diagram (see Figure 3) between Point A and B within the limitsgiven in 5.2.1 and 5.2.2. Point A is when the machine leaves the straight-ahead direction and point B is whereit has achieved a 12.0 m turning radius. The speed for performing the maneuver shall be 10 km/h 2 km/h.
27、 Inthe case of machines with a maximum speed of less than 10 km/h, then speed shall be the maximumattainable. FIGURE 3TEST COURSE5.2.1 Under normal working conditions, the steering effort required to perform the maneuver shall not exceed250 N and the duration to achieve the specified turning radius
28、shall not exceed 4 s for machines capable ofover 25 km/h. For speeds of 25 km/h and less, the duration shall not exceed 5 s.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1790 Reaffirmed MAY200
29、8-5-5.2.2 Under conditions where the fluid power energy source has failed or is inert, the steering effort required toperform the maneuver shall not exceed 600 N and the duration to achieve the specified turning radius shallnot exceed 6 s for machines capable of over 25 km/h. For speeds of 25 km/h a
30、nd less, the duration shall notexceed 8 s.5.3 Steering RateThe output of the fluid power energy source and metering displacement of the control unitshall permit a steering wheel rotational speed of 80 rpm minimum without the control unit acting to manuallypump fluid. Under engine idling conditions,
31、the steering wheel rotational speed may be reduced to a minimumof 40 rpm.PREPARED BY THE SAE MACHINERY TECHNICAL COMMITTEE MTC SC2SWEEPERS AND SCRUBBERSREAFFIRMED BY THE SAE MACHINE TECHNICAL COMMITTEE SC2SWEEPER, CLEANER, AND MACHINERYCopyright SAE International Provided by IHS under license with S
32、AENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J1790 Reaffirmed MAY2008RationaleMany sweeper and scrubber machines are purpose designed and operate on paved and roadsurfaces amongst other machines and road users.In the construction of such machines, the loca
33、tion of the drivers cab with regard to the steered roadwheels and layout of the sweeping and collection mechanisms may inhibit the fitment of a mechanicallinkage for the steering function. In these circumstances, machines may be constructed with a hydraulicservo-assisted steering system where the dr
34、ivers steering wheel operates a control unit that meters fluidto a steering actuator linked to the steered road wheels.This SAE Standard proposes a set of performance requirements for a single-circuit hydraulic servo-assisted steering system as would be applied to machines described in SAE J2130.Rel
35、ationship of SAE Standard to ISO StandardNot applicable.ApplicationThe SAE Standard applies to self-propelled, driver-operated sweepers and scrubbers asdefined in SAE J2130.Reference SectionSAE J2130Self-Propelled SweepersSAE J1511/ISO 5010:1994Steering for Off-Road Rubber-Tired MachinesISO 789-11:1
36、996Agricultural tractorsTest proceduresPart 11: Steering capability of wheeled tractorsISO 5010:1992Earth-moving machineryRubber-tired machinesSteering requirementsISO 10998:1995Agricultural wheeled tractorsSteering requirementsDeveloped by the SAE Machinery Technical Committee MTC SC2Sweepers and ScrubbersSponsored by the SAE Machinery Technical CommitteeCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
