WO2007036767A1 - Forklift truck steering device and forklift truck - Google Patents

Forklift truck steering device and forklift truck Download PDF

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Publication number
WO2007036767A1
WO2007036767A1 PCT/IB2006/001174 IB2006001174W WO2007036767A1 WO 2007036767 A1 WO2007036767 A1 WO 2007036767A1 IB 2006001174 W IB2006001174 W IB 2006001174W WO 2007036767 A1 WO2007036767 A1 WO 2007036767A1
Authority
WO
WIPO (PCT)
Prior art keywords
steering
truck
control unit
column assembly
steering device
Prior art date
Application number
PCT/IB2006/001174
Other languages
French (fr)
Inventor
Vanni Righi
Original Assignee
Cesab Carrelli Elevatori S.P.A.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cesab Carrelli Elevatori S.P.A. filed Critical Cesab Carrelli Elevatori S.P.A.
Publication of WO2007036767A1 publication Critical patent/WO2007036767A1/en

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D6/00Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits
    • B62D6/008Control of feed-back to the steering input member, e.g. simulating road feel in steer-by-wire applications
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D5/00Power-assisted or power-driven steering
    • B62D5/001Mechanical components or aspects of steer-by-wire systems, not otherwise provided for in this maingroup
    • B62D5/005Mechanical components or aspects of steer-by-wire systems, not otherwise provided for in this maingroup means for generating torque on steering wheel or input member, e.g. feedback
    • B62D5/006Mechanical components or aspects of steer-by-wire systems, not otherwise provided for in this maingroup means for generating torque on steering wheel or input member, e.g. feedback power actuated
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F17/00Safety devices, e.g. for limiting or indicating lifting force
    • B66F17/003Safety devices, e.g. for limiting or indicating lifting force for fork-lift trucks
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/0755Position control; Position detectors
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/07568Steering arrangements
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B66HOISTING; LIFTING; HAULING
    • B66FHOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075Constructional features or details
    • B66F9/20Means for actuating or controlling masts, platforms, or forks
    • B66F9/24Electrical devices or systems

Definitions

  • the present invention relates to a forklift truck steering device .
  • Forklift trucks of the known type comprise a vehicle with three or four wheels, driven electrically or by an internal combustion engine, two motor-driven horizontal forks, positioned at the front of the vehicle and able to move vertically to lift loads of various types, and a rear counterweight for balancing said loads.
  • Such trucks may have different shapes and characteristics depending on the number of wheels and the fact that the relative vehicles are front- or rear-wheel drive .
  • three-wheeled forklift trucks two of the three wheels are positioned at the front along a shared axis of rotation, whilst the third wheel is positioned at the back at a vehicle longitudinal median plane.
  • the vehicle steering device acts on the rear wheel, which may or may not be a driving wheel.
  • the steering device In both three-wheeled and four-wheeled forklift trucks, the steering device is designed to guarantee a rather small turning radius. Although this on one hand allows great manoeuvrability in limited spaces, on the other hand it is often the cause of accidents . It has been amply demonstrated that the main cause of truck lateral tipping is the fact that less skilled truck drivers set a turning radius which is too small relative to the vehicle translation speed and/or to the truck load conditions. The problem is accentuated by the increasing spread of hydraulically assisted steering which means that the steering wheel offers very little resistance to rotation, often inadequate for the driving and load conditions .
  • the aim of the present invention is to provide a forklift truck steering device which simultaneously guarantees a high level of manoeuvrability and low risk of lateral tipping.
  • the present invention provides a forklift truck steering device with the characteristics described in claim 1 or in any of the claims directly or indirectly dependent on claim 1.
  • Figure 1 illustrates a forklift truck equipped with a steering device made in accordance with the present invention
  • Figure 2 is an exploded view of the front part of the forklift truck steering device illustrated in Figure 1;
  • Figure 3 is a schematic overview, in the form of a block diagram, of the forklift truck steering device illustrated in Figure 1.
  • the truck 1 comprises a vehicle 2, two front driving wheels 3, two rear steered wheels 4 and two horizontal front forks 5, which are motor-driven (in the known way, not illustrated) for lifting various types of loads (not illustrated) .
  • the wheels 4 are controlled by a steering device 6, which is the subject matter of the present invention and is illustrated in detail in Figures 2 and 3.
  • the steering device 6 comprises a steering wheel 7, mechanically integral with a steering column 8.
  • the steering column 8 is supported in such a way that it can rotate by the vehicle 2 chassis and connected to it there is an encoder 9 connected to a control unit 10 so that it can signal to the latter the angular position of the steering wheel 7.
  • a brushless electric motor 11 is also connected to the steering column 8, with a reduction unit 12 inserted between them.
  • the electric motor 11 is in turn connected to the control unit 10 by which it is controlled for applying to the steering column 8 a torque with variable intensity and opposing the effort applied to the steering wheel 7 by the truck driver.
  • the angular position of the wheels 4 is controlled by a steering device 6 actuator 13, based on the signal supplied to the control unit 10 by the encoder 9, labelled A, and on a feedback signal B supplied to the control unit 10 by a sensor 14 which detects the actual rotation of the wheels 4.
  • the actuator 13 is of the recirculating ball screw type, driven by an integrated electric motor.
  • the steering device 6 control unit 10 also receives a signal
  • the control unit 10, which together with the encoder 9, the motor 11, the tachometer 15, the load cell 16 and the position sensor 17, is part of a truck 1 control system 18, may have an interface for connection to a truck 1 communication network, for example of the CAN BUS or CAN OPEN type, so that it can receive one or more of the above-mentioned signals directly from the communication network.
  • a truck 1 communication network for example of the CAN BUS or CAN OPEN type
  • the steering device 6 encoder 9 signals to the control unit 10 the angle and speed of rotation to be imparted to the wheels 4 through the actuator 13.
  • the sensor 14 signals the actual rotation of the wheels 4 to the control unit 10 which reacts by eliminating any differences between the position reached and that expected.
  • one function of the motor 11 is to transmit to the truck driver the same driving sensations that he would have with a conventional mechanical steering device, that is to say, greater or lesser resistance to rotation of the steering wheel 7 depending on the obstacles, or the roughness of the ground, which the wheels encounter as they describe the steering trajectory.
  • the increase in current intensity required by the electric motor of the actuator 13 in order to generate the torque needed to overcome the sudden obstacle opposing the steering of the wheels 4 is used by the control unit 10 to control the steering device 6 motor 11.
  • a second function of the motor 11 is to allow the truck driver to feel the mechanical end of stroke when the wheels 4 reach the full steering lock position.
  • a third function of the motor 11 is a safety function, specifically to prevent the risk of truck 1 lateral tipping. For this function, the motor 11 operates as a brake based on a saved control map which relates the vehicle 2 translation speed to the maximum steering allowed at that speed without truck 1 lateral tipping.
  • the control unit 10 by means of the motor 11 and based on its control map, actively stiffens the movement of the steering wheel 7 to maintain a safe turning radius. This stiffening of the steering wheel is also immediately felt by the truck driver, who instinctively slows down.
  • the vehicle 2 slowing may be left to the truck driver as described above, or it may be applied by the control unit 10, together with the steering wheel 7 braking, by means of programmed actuator 13 control and/or controlled and programmed braking of the wheels 4.
  • the control unit 10 control map may take into account not just the vehicle 2 translation speed, but also other variables, such as the height of the forks 5 and the size of the load supported by them. In this case, the extent of the steering wheel 7 braking, the vehicle 2 translation speed and steering set by the truck driver being equal, is less if there is a load on the forks 5 and the forks are in the lowered position, for example up to 30 cm from the ground. Under these load conditions the truck 1 is more stable than in the absence of a load. In other words, the motor 11, in its function opposing rotation of the steering wheel - steering column assembly, is actively controlled by the control unit 10 according to the latter 's programming to provide an opposing torque with intensity which varies according to the different speed and/or load conditions of the truck 1.
  • the extent of the steering wheel 7 braking, the vehicle 2 translation speed and steering set by the truck driver being equal, is greater than in the absence of a load and the control unit 10 accompanies this, based on its programming and preferably in advance, with a reduction in the vehicle 2 translation speed.
  • the extent of the steering wheel 7 braking, the vehicle 2 translation speed and steering set by the truck driver being equal is decidedly greater than in the absence of a load and the control unit 10 accompanies this, based on its programming and preferably in advance, with a large reduction in the vehicle 2 translation speed.
  • the motor 11 is also compact and allows the steering device
  • the motor 11 constitutes means 19 for opposing the rotation of the steering wheel - steering column assembly 7, 8.
  • the opposing means 19 comprise, as an alternative to the motor 11, an electromagnetic clutch device.
  • Said electromagnetic clutch device is controlled by the control unit 10 according to the electrical current intensity required for steering the wheels 3 (if the steering device actuator is electric) , or according to the oil pressure reading (if the steering device actuator is hydraulic) .
  • the greater the electrical current intensity supplied to the clutch device the more the clutch pack closes on the steering axle, thus increasing its opposing action.
  • the tachometer 15 consists of an encoder inserted in a respective electric traction motor.

Abstract

A steering device (6) for a forklift truck (1) in which the .steering wheel - steering column assembly (7, 8) and the actuator (13) which controls the steered wheels (4) of the truck (1) are mechanically isolated from one another and connected by a control unit (18) with an encoder (9) connected to the steering wheel - steering column assembly (Il 8) and with a control unit (10) which controls the actuator (13) , for steering the truck (1) based on signals supplied to the control unit (10) by the encoder (9) . The steering device comprises sensor means (15,16, 17) for detecting the truck speed and/or load conditions, and means (19) for opposing rotation of the steering wheel .

Description

Description
Forklift truck steering device and forklift truck
Technical Field
The present invention relates to a forklift truck steering device .
Background Art
Forklift trucks of the known type comprise a vehicle with three or four wheels, driven electrically or by an internal combustion engine, two motor-driven horizontal forks, positioned at the front of the vehicle and able to move vertically to lift loads of various types, and a rear counterweight for balancing said loads.
Such trucks, irrespective of their lifting capacity, may have different shapes and characteristics depending on the number of wheels and the fact that the relative vehicles are front- or rear-wheel drive .
In three-wheeled forklift trucks, two of the three wheels are positioned at the front along a shared axis of rotation, whilst the third wheel is positioned at the back at a vehicle longitudinal median plane. The vehicle steering device acts on the rear wheel, which may or may not be a driving wheel.
Four-wheeled forklift trucks are front-wheel drive, whilst the steering device acts on the rear wheels.
In both three-wheeled and four-wheeled forklift trucks, the steering device is designed to guarantee a rather small turning radius. Although this on one hand allows great manoeuvrability in limited spaces, on the other hand it is often the cause of accidents . It has been amply demonstrated that the main cause of truck lateral tipping is the fact that less skilled truck drivers set a turning radius which is too small relative to the vehicle translation speed and/or to the truck load conditions. The problem is accentuated by the increasing spread of hydraulically assisted steering which means that the steering wheel offers very little resistance to rotation, often inadequate for the driving and load conditions .
Disclosure of the Invention
The aim of the present invention is to provide a forklift truck steering device which simultaneously guarantees a high level of manoeuvrability and low risk of lateral tipping.
Accordingly, the present invention provides a forklift truck steering device with the characteristics described in claim 1 or in any of the claims directly or indirectly dependent on claim 1.
Brief Description of the Drawings
The present invention is now described, by way of example and without limiting the scope of application, with reference to the accompanying drawings , in which :
Figure 1 illustrates a forklift truck equipped with a steering device made in accordance with the present invention;
Figure 2 is an exploded view of the front part of the forklift truck steering device illustrated in Figure 1; an
Figure 3 is a schematic overview, in the form of a block diagram, of the forklift truck steering device illustrated in Figure 1.
Detailed description of the Preferred Embodiments of the Invention In Figure 1 the numeral 1 denotes a four-wheeled forklift truck .
The truck 1 comprises a vehicle 2, two front driving wheels 3, two rear steered wheels 4 and two horizontal front forks 5, which are motor-driven (in the known way, not illustrated) for lifting various types of loads (not illustrated) .
The wheels 4 are controlled by a steering device 6, which is the subject matter of the present invention and is illustrated in detail in Figures 2 and 3. The steering device 6 comprises a steering wheel 7, mechanically integral with a steering column 8. The steering column 8 is supported in such a way that it can rotate by the vehicle 2 chassis and connected to it there is an encoder 9 connected to a control unit 10 so that it can signal to the latter the angular position of the steering wheel 7.
A brushless electric motor 11 is also connected to the steering column 8, with a reduction unit 12 inserted between them. The electric motor 11 is in turn connected to the control unit 10 by which it is controlled for applying to the steering column 8 a torque with variable intensity and opposing the effort applied to the steering wheel 7 by the truck driver. The angular position of the wheels 4 is controlled by a steering device 6 actuator 13, based on the signal supplied to the control unit 10 by the encoder 9, labelled A, and on a feedback signal B supplied to the control unit 10 by a sensor 14 which detects the actual rotation of the wheels 4. The actuator 13 is of the recirculating ball screw type, driven by an integrated electric motor.
The steering device 6 control unit 10 also receives a signal
C, relative to the vehicle 2 speed, from a tachometer 15, a signal
D, relative to the truck 1 load condition, from a load cell 16 mounted on the rear steering axle, and a signal E, relative to the height of the forks 5, from a position sensor 17.
The control unit 10, which together with the encoder 9, the motor 11, the tachometer 15, the load cell 16 and the position sensor 17, is part of a truck 1 control system 18, may have an interface for connection to a truck 1 communication network, for example of the CAN BUS or CAN OPEN type, so that it can receive one or more of the above-mentioned signals directly from the communication network.
The following is a description of steering device 6 operation.
After the steering wheel 7 is rotated, the steering device 6 encoder 9 signals to the control unit 10 the angle and speed of rotation to be imparted to the wheels 4 through the actuator 13. The sensor 14 signals the actual rotation of the wheels 4 to the control unit 10 which reacts by eliminating any differences between the position reached and that expected.
In the absence of a mechanical connection between the steering wheel 7 and the steered wheels 4, one function of the motor 11 is to transmit to the truck driver the same driving sensations that he would have with a conventional mechanical steering device, that is to say, greater or lesser resistance to rotation of the steering wheel 7 depending on the obstacles, or the roughness of the ground, which the wheels encounter as they describe the steering trajectory. Specifically, the increase in current intensity required by the electric motor of the actuator 13 in order to generate the torque needed to overcome the sudden obstacle opposing the steering of the wheels 4 is used by the control unit 10 to control the steering device 6 motor 11.
A second function of the motor 11 is to allow the truck driver to feel the mechanical end of stroke when the wheels 4 reach the full steering lock position. A third function of the motor 11 is a safety function, specifically to prevent the risk of truck 1 lateral tipping. For this function, the motor 11 operates as a brake based on a saved control map which relates the vehicle 2 translation speed to the maximum steering allowed at that speed without truck 1 lateral tipping.
If the truck driver rotates the steering wheel 7 too far, the control unit 10, by means of the motor 11 and based on its control map, actively stiffens the movement of the steering wheel 7 to maintain a safe turning radius. This stiffening of the steering wheel is also immediately felt by the truck driver, who instinctively slows down.
The vehicle 2 slowing may be left to the truck driver as described above, or it may be applied by the control unit 10, together with the steering wheel 7 braking, by means of programmed actuator 13 control and/or controlled and programmed braking of the wheels 4.
The control unit 10 control map may take into account not just the vehicle 2 translation speed, but also other variables, such as the height of the forks 5 and the size of the load supported by them. In this case, the extent of the steering wheel 7 braking, the vehicle 2 translation speed and steering set by the truck driver being equal, is less if there is a load on the forks 5 and the forks are in the lowered position, for example up to 30 cm from the ground. Under these load conditions the truck 1 is more stable than in the absence of a load. In other words, the motor 11, in its function opposing rotation of the steering wheel - steering column assembly, is actively controlled by the control unit 10 according to the latter 's programming to provide an opposing torque with intensity which varies according to the different speed and/or load conditions of the truck 1.
If the forks 5 support the load and are in an intermediate position, for example between 30 cm and 70 cm from the ground, the extent of the steering wheel 7 braking, the vehicle 2 translation speed and steering set by the truck driver being equal, is greater than in the absence of a load and the control unit 10 accompanies this, based on its programming and preferably in advance, with a reduction in the vehicle 2 translation speed.
If the forks 5 support the load and are in a raised position, for example more than 70 cm from the ground, the extent of the steering wheel 7 braking, the vehicle 2 translation speed and steering set by the truck driver being equal, is decidedly greater than in the absence of a load and the control unit 10 accompanies this, based on its programming and preferably in advance, with a large reduction in the vehicle 2 translation speed.
It should be noticed that the stiffening of the steering wheel 7, actively controlled by the control unit 10 according to the various speed and load conditions, requires a fast and precise actuator device, such as the motor 11 described above.
The motor 11 is also compact and allows the steering device
6 to be designed in such a way that the steering column 8 is positioned precisely where the truck driver's form requires it, with obvious ergonomic advantages .
For the forklift truck 1, the motor 11 constitutes means 19 for opposing the rotation of the steering wheel - steering column assembly 7, 8. Advantageously, in an alternative embodiment of the present invention not illustrated, the opposing means 19 comprise, as an alternative to the motor 11, an electromagnetic clutch device. Said electromagnetic clutch device, not illustrated, is controlled by the control unit 10 according to the electrical current intensity required for steering the wheels 3 (if the steering device actuator is electric) , or according to the oil pressure reading (if the steering device actuator is hydraulic) . Obviously, the greater the electrical current intensity supplied to the clutch device, the more the clutch pack closes on the steering axle, thus increasing its opposing action.
Advantageously, with trucks 1 which have electric traction motors for the wheels 3, the tachometer 15 consists of an encoder inserted in a respective electric traction motor.
Finally, it must be emphasised that what is described above also applies for a three-wheeled forklift truck.

Claims

Claims
1. A steering device for a forklift truck having at least one steered wheel (4) ; the steering device (6) comprising a steering wheel - steering column assembly (7, 8) and actuator means (13) for steering the truck (1) according to the rotation imparted by the operator to the steering wheel - steering column assembly (7, 8); the steering device (6) being characterised in that the steering wheel - steering column assembly (7, 8) and the actuator means (13) are mechanically isolated from one another and connected by a control system (18) which comprises an encoder (9) connected to the steering wheel - steering column assembly (7, 8) and a control unit (10) which controls the actuator means (13) to steer the truck (1) based on the signals supplied to the control unit (10) by the encoder (9); the control system (18) also comprising sensor means (15, 16, 17), connected to the control unit (10) and designed to detect the truck (1) speed and/or load conditions, and means (19) for opposing rotation of the steering wheel - steering column assembly (7, 8), actively controlled by the control unit (10) when, for the truck (1) speed and/or load conditions detected by the sensor means (15, 16, 17), the operator sets a turning radius lower than or equal to the limit turning radius at which truck (1) lateral tipping occurs.
2. The steering device according to claim 1, characterised in that the means (19) opposing rotation of the steering wheel - steering column assembly (7, 8) are actively controlled by the control unit (10) according to the control unit (10) programming, providing an opposing torque with intensity which varies according to the different speed and/or load conditions of the truck (1) .
3. The steering device according to claim 1 or 2, characterised in that the means (19) for opposing rotation of the steering wheel - steering column assembly (7, 8) comprise an electric motor (11) actively controlled by the control unit (10) .
4. The steering device according to claim 1 or 2 , characterised in that the means (19) for opposing rotation of the steering wheel - steering column assembly (7, 8) comprise a clutch device actively controlled by the control unit (10) .
5. The steering device according to any of the claims from 1 to 4, characterised in that the control unit (10) is programmed to control the braking of the actuator means (13) and/or the steered wheel (4) , together with active control of the means (19) for opposing rotation of the steering wheel - steering column assembly (7, 8), according to the various truck (1) speed and/or load conditions detected by the sensor means (15, 16, 17) .
6. The steering device according to claim 4 or 5, characterised in that the control unit (10) has an interface for connected to a truck (1) communications network, of the CAM BUS or CAN OPEN type.
7. A forklift truck, characterised in that it comprises a steering device according to any of the claims from 1 to 6.
PCT/IB2006/001174 2005-09-28 2006-04-18 Forklift truck steering device and forklift truck WO2007036767A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITBO20050587 ITBO20050587A1 (en) 2005-09-28 2005-09-28 STEERING DEVICE FOR A FORKLIFT AND FORKLIFT TROLLEY
ITBO2005A000587 2005-09-28

Publications (1)

Publication Number Publication Date
WO2007036767A1 true WO2007036767A1 (en) 2007-04-05

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Application Number Title Priority Date Filing Date
PCT/IB2006/001174 WO2007036767A1 (en) 2005-09-28 2006-04-18 Forklift truck steering device and forklift truck

Country Status (3)

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IT (1) ITBO20050587A1 (en)
TW (1) TWI365848B (en)
WO (1) WO2007036767A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009130718A1 (en) 2008-04-21 2009-10-29 Cesab Carrelli Elevatori S.P.A. Safety system for counterbalanced lift trucks and similar vehicles
EP2947044A1 (en) * 2014-05-19 2015-11-25 STILL GmbH Method for steering control in an industrial truck
JP2022063481A (en) * 2020-10-12 2022-04-22 株式会社豊田自動織機 Unmanned industrial vehicle

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10157797A1 (en) * 2000-11-29 2002-09-19 Continental Teves Ag & Co Ohg Steering wheel simulator unit has reaction torque simulator with steering wheel shaft fixed to steering wheel without relative rotation
GB2378165A (en) * 1999-07-14 2003-02-05 Lansing Linde Ltd A "steer-by-wire" device for a vehicle
US20040262071A1 (en) * 2001-07-25 2004-12-30 Duits Johannes Adrianus Maria Steer unit for steer-by-wire

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2378165A (en) * 1999-07-14 2003-02-05 Lansing Linde Ltd A "steer-by-wire" device for a vehicle
DE10157797A1 (en) * 2000-11-29 2002-09-19 Continental Teves Ag & Co Ohg Steering wheel simulator unit has reaction torque simulator with steering wheel shaft fixed to steering wheel without relative rotation
US20040262071A1 (en) * 2001-07-25 2004-12-30 Duits Johannes Adrianus Maria Steer unit for steer-by-wire

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009130718A1 (en) 2008-04-21 2009-10-29 Cesab Carrelli Elevatori S.P.A. Safety system for counterbalanced lift trucks and similar vehicles
EP2947044A1 (en) * 2014-05-19 2015-11-25 STILL GmbH Method for steering control in an industrial truck
JP2022063481A (en) * 2020-10-12 2022-04-22 株式会社豊田自動織機 Unmanned industrial vehicle
JP7439724B2 (en) 2020-10-12 2024-02-28 株式会社豊田自動織機 unmanned industrial vehicle

Also Published As

Publication number Publication date
ITBO20050587A1 (en) 2007-03-29
TWI365848B (en) 2012-06-11
TW200711979A (en) 2007-04-01

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