Abstract: Embodiments include an industrial truck comprising a chassis, which is supported by at least two front wheels and by at least one rear wheel, a mast for a load-carrying apparatus, wherein the front wheels are rotatably arranged on wheel arms that protrude forwards from the mast support region of the chassis, and configured for suppressing and reducing vibrations, wherein at least one of the wheel arms, is split into at least two wheel arm portions, which are mounted by a bearing arrangement so as to be able to perform movements relative to one another, wherein relative movements of the wheel arm portions are influenced, in order to suppress or reduce vibrations.

Abstract: A forklift truck includes a truck body, a fork, a mast, tilting and lifting mechanisms, tilt and lift levers, tilting and lifting operation detectors, an auxiliary switch, a tilt angle detector and a controller. The tilt and lift levers are adapted to operate the tilting and lifting mechanisms, respectively. The auxiliary switch is disposed on the lift lever at a position where the auxiliary switch and the lift lever are operable by the same operator's hand. The controller is adapted to control the tilting and lifting mechanisms based on signals from the tilting and lifting operation detectors and the auxiliary switch. When the auxiliary switch is in operative position and the lifting operation detector detects that the lift lever is in operative position, the controller controls the tilting mechanism so as to tilt the fork to have a predetermined tilt angle based on a signal from the tilt angle detector.

Abstract: A system and method that maintains the dynamic stability of a material handling vehicle having a vertical lift. The method allows static vehicle properties, such as vehicle weight, wheelbase length, and wheel configuration, and dynamic operating parameters, such as vehicle velocity, floor grade, lift position, and load weight, to be accounted for when maintaining the dynamic stability of a moving material handling vehicle. The method may include calculating and predicting center-of-gravity parameters, wheel loads, and projected force vectors multiple times a second and adjusting vehicle operating parameters in response thereto to maintain vehicle stability.

Abstract: A method and system for automatically loading and unloading a transport is disclosed. A guidance system follows a travel path to a position near the transport and then a sensor profiles a transport so that a transport path is determined for an AGV to follow into the transport to place a load and for exiting the transport upon placement of the load.

Abstract: A forward-control counterweight fork-lift truck has a liftable and tiltable load-lifting device (1), a traction drive and operating drives for the movement of the load-lifting device (1). A calculation model (D) is stored in a control device (SE), to which directly or indirectly acting sensors (S) are connected for detecting the lifting load (L), the lifting height (H), the tilting angle (WM), the load torque (M), the direction of travel (R), the driving speed (V), and the steering angle (WL). The control device (SE) is designed to determine a driving and load state (Z) based on the detected physical variables (L, H, WM, M, R, V, WL) and the stored calculation model (D) and is operatively connected to the traction drive and the operating drives. Depending on the driving and load state (Z) determined, the operating speed, starting and braking acceleration, and driving speed are each reduced.

Abstract: A pallet positioner includes a support frame that consists of a main upright structure with a pair of spaced, parallel outriggers extending horizontally at ground level. The distal ends of the outriggers are connected by a low-profile ramp. The upright structure includes a pair of vertical guide masts rigidly mounted on a horizontal base bracing the proximal ends of the outriggers. A pneumatically and hydraulically controlled, or electrically and hydraulically controlled, cantilevered carrier with a rotatable platform is mounted for vertical motion along the vertical guide masts. When the carrier travels downward, the carrier stops automatically at a level above the outriggers and must be manually restarted. A braking system under the platform prevents rotation thereof at ground level.

Abstract: The invention relates to a tilting mechanism for a lifting structure (14) of an industrial truck (10), the lifting structure (14) being mounted so as to be able to pivot about a hinge pin (D) between an at least approximately vertical operating position and a position, inclined with respect to the vertical, of abutment against the frame (12) of the industrial truck (10), characterized in that the tilting mechanism (22) is linked (36, 38) to the lifting structure (14) and to the frame (12, 54) of the industrial truck (10) and is embodied in such a way that the lifting structure (14) can be fixed in any desired pivoting positions between the operating position and the abutment position. Furthermore, the invention relates to an industrial truck comprising a tilting mechanism of this type and to a method for transporting an industrial truck of this type.

Abstract: A forward-control counterweight fork-lift truck has a liftable and tiltable load-lifting device (1), a traction drive, operating drives, and a steering drive. A calculation model (D) based on vehicle-specific information is stored in a control device (SE). A plurality of sensors (S) detect physical variables (V, R, H, M, L, WM, WL, BL, BQ, G) relevant to the tipping behavior of the industrial truck. The control device (SE) determines a driving and load state (Z) based on the detected physical variables (V, R, H, M, L, WM, WL, BL, BQ, G) and the stored calculation model (D) and is operatively connected to the traction drive, the operating drives, and the steering drive such that, depending on the driving and load state (Z) determined, corrective interventions (K1, K2) which maintain or increase the tipping stability can be carried out.

Abstract: An industrial vehicle has an armrest. The armrest extends in a front-and-rear direction of the vehicle. A plurality of operating members for controlling a loading operation of the vehicle is arranged on a front side of the armrest. The operating members include a first operating member for controlling an actuator for loading and a second operating member for controlling the actuator. The first operating member and the second operating member are separately arranged.

Abstract: A fluid power load-clamping system includes at least one fluid valve for variably regulating the maximum fluid pressure causing closure of the clamp. Preferably the valve increases the maximum fluid pressure automatically in relation to the measured magnitude of the weight of the load to regulate the load-gripping force. A controller causes the valve to permit a relatively high maximum fluid pressure as the clamp closes toward the load to enable high initial clamp closure speed. Thereafter the valve automatically reduces the maximum pressure as the clamping surfaces close into a predetermined relationship with the load, and then increases the maximum pressure to regulate the gripping force. Other preferable features include continuous weight-responsive automatic regulation of the gripping pressure while the load is supported by the clamp, and compensation of the weight measurement for the longitudinally-extensible position of the lifting mechanism, to maximize the accuracy of the load-weight measurement.

Abstract: An industrial truck has a chassis (1), a lifting frame (5), a load holding device (10) that can move vertically along the lifting frame (5), and at least one movement device to move the lifting frame (5) relative to the chassis (1). The acceleration and/or the speed of movement of the lifting frame (5) that can be achieved by the movement device can be controlled as a function of at least one operating parameter of the industrial truck. The operating parameter is measured at least approximately continuously. One operating parameter is the current lifting height of the load holding device (10). An additional operating parameter is the weight of a load that is being held by the load holding device (10).

Abstract: A fluid power load-clamping system includes at least one fluid valve for variably regulating the maximum fluid pressure causing closure of the clamp. Preferably the valve increases the maximum fluid pressure automatically in relation to the measured magnitude of the weight of the load to regulate the load-gripping force. A controller causes the valve to permit a relatively high maximum fluid pressure as the clamp closes toward the load to enable high initial clamp closure speed. Thereafter the valve automatically reduces the maximum pressure as the clamping surfaces close into a predetermined relationship with the load, and then increases the maximum pressure to regulate the gripping force. Other preferable features include continuous weight-responsive automatic regulation of the gripping pressure while the load is supported by the clamp, and compensation of the weight measurement for the longitudinally-extensible position of the lifting mechanism, to maximize the accuracy of the load-weight measurement.

Abstract: An industrial truck has a chassis (1), a lifting frame (5), load holding means (10) that can move vertically along the lifting frame (5), and at least one movement device to move the lifting frame (5) relative to the chassis (1). The acceleration and/or the speed of movement of the lifting frame (5) that can be achieved by the movement device can be controlled as a function of at least one operating parameter of the industrial truck. The operating parameter is measured at least approximately continuously. One operating parameter is the current lifting height of the load holding means (10). An additional operating parameter is the weight of a load that is being held by the load holding means (10).

Abstract: A fluid power load-clamping system includes at least one fluid valve for variably regulating the maximum fluid pressure causing closure of the clamp. Preferably the valve increases the maximum fluid pressure automatically in relation to the measured magnitude of the weight of the load to regulate the load-gripping force. A controller causes the valve to permit a relatively high maximum fluid pressure as the clamp closes toward the load to enable high initial clamp closure speed. Thereafter the valve automatically reduces the maximum pressure as the clamping surfaces close into a predetermined relationship with the load, and then increases the maximum pressure to regulate the gripping force. Other preferable features include continuous weight-responsive automatic regulation of the gripping pressure while the load is supported by the clamp, and compensation of the weight measurement for the longitudinally-extensible position of the lifting mechanism, to maximize the accuracy of the load-weight measurement.

Abstract: A fluid power load-clamping system includes at least one fluid valve for variably regulating the maximum fluid pressure causing closure of the clamp. Preferably the valve increases the maximum fluid pressure automatically in relation to the measured magnitude of the weight of the load to regulate the load-gripping force. A controller causes the valve to permit a relatively high maximum fluid pressure as the clamp closes toward the load to enable high initial clamp closure speed. Thereafter the valve automatically reduces the maximum pressure as the clamping surfaces close into a predetermined relationship with the load, and then increases the maximum pressure to regulate the gripping force. Other preferable features include continuous weight-responsive automatic regulation of the gripping pressure while the load is supported by the clamp, and compensation of the weight measurement for the longitudinally-extensible position of the lifting mechanism, to maximize the accuracy of the load-weight measurement.

Abstract: A fluid power load-clamping system includes at least one fluid valve for variably regulating the maximum fluid pressure causing closure of the clamp. Preferably the valve increases the maximum fluid pressure automatically in relation to the measured magnitude of the weight of the load to regulate the load-gripping force. A controller causes the valve to permit a relatively high maximum fluid pressure as the clamp closes toward the load to enable high initial clamp closure speed. Thereafter the valve automatically reduces the maximum pressure as the clamping surfaces close into a predetermined relationship with the load, and then increases the maximum pressure to regulate the gripping force. Other preferable features include an automatic limit on the rate of lift of the load during weighing, and compensation of the weight measurement for the longitudinally-extensible position of the lifting mechanism, to maximize the accuracy of the load-weight measurement.

Abstract: A tilt speed control apparatus for fork lift comprises a mast pivotally supported on a body frame. A fork is supported by the mast. The fork is lifted and lowered and is constructed to carry a load. A pump sends hydraulic oil to a tilt cylinder. A motor drives the pump. A lever is actuated to tilt the mast. A controller detects that the lever has been actuated. The controller produces a signal relating to the height of the load carrier. When the controller detects that the lever has been actuated, the controller controls the motor according to the signal such that the speed of the motor is relatively low when the position of the fork is relatively high. This permits a tilting speed controlling apparatus that optimizes the tilting speed of the mast.

Abstract: A fluid power load-clamping system includes at least one fluid valve for variably regulating the maximum fluid pressure causing closure of the clamp. Preferably the valve increases the maximum fluid pressure automatically in relation to the measured magnitude of the weight of the load to regulate the load-gripping force. A controller causes the valve to permit a relatively high maximum fluid pressure as the clamp closes toward the load to enable high initial clamp closure speed. Thereafter the valve automatically reduces the maximum pressure as the clamping surfaces close into a predetermined relationship with the load, and then increases the maximum pressure to regulate the gripping force. Other preferable features include continuous weight-responsive automatic regulation of the gripping pressure while the load is supported by the clamp, and compensation of the weight measurement for the longitudinally-extensible position of the lifting mechanism, to maximize the accuracy of the load-weight measurement.

Abstract: A device for controlling tilt of a forklift mast. A fork for carrying an object is supported by the mast so that the fork is lifted or lowered. A tilt cylinder operates to tilt the mast hydraulically. A hydraulic valve supplies oil to the tilt cylinder in correspondence with the position of a tilt lever. The tilt cylinder tilts the mast at a speed corresponding to the flow rate of the oil supplied by the valve. A restricting valve is provided for restricting the maximum flow rate of the oil. When the fork is located below a predetermined reference position, the controller fully opens the restricting valve. However, when the fork is located at the reference position or higher, the controller restricts the opening of the restricting valve, thus restricting the maximum tilt speed of the mast. This stabilizes the forklift.

Abstract: An industrial vehicle including an axle to which wheels are mounted and supported to pivot vertically relative to a body of the vehicle. The vehicle includes a pivot control apparatus for controlling pivoting of the axle. The industrial vehicle further includes a controller for determining whether an abnormality has occurred in the pivot control apparatus. A warning lamp having two or more different modes is located in the cabin. The modes include an abnormality mode for indicating the occurrence of an abnormality in the pivot control apparatus and a normality mode for indicating normal functioning of the pivot control apparatus. The controller also notifies the operator of two or more additional different pieces of information using the modes of the warning lamp. That is, the single warning lamp also indicates the reason for restricting the axle by its color.

Abstract: A lift control valve is switched based on the manipulation of a lift lever, so that a lift cylinder extends or retracts to move a fork, supported on a mast, to move up or down. A check valve, which is actuated with a pilot pressure, is placed between the lift control valve and the lift cylinder. A pilot pipe led out from a pipe directly coupled to an oil tank is connected to a port of the check valve. A tilt control valve is switched based on the manipulation of a tilt lever, so that a tilt cylinder extends or retracts to tilt the mast. An electromagnetic valve is disposed between the tilt cylinder and the tilt control valve. When values necessary to drive the fork are detected, a controller control the electromagnetic valve based on those values.

Abstract: A fork lift truck includes a body, a drive mechanism supported on the body for effecting movement of the body, and a fork carrying assembly carrying forks which can be moved in height between a lowered position and desired raised positions. A tilt cylinder is provided for tilting the forks through a fork tilt range. The truck further includes a pressure sensor capable of generating signals indicative of the weight of a load on the forks, a fork tilt position sensor capable of being activated when the forks are tilted to extremes of the fork tilt range, and a controller. The controller is coupled to the drive mechanism, the pressure sensor and the fork tilt position sensor.

Abstract: A hydraulic device for a forklift is disclosed. The forklift includes a tilting mast and a fork supported by the mast so that the fork is lifted and lowered. A tilt cylinder operates to tilt the mast by means of oil supplied by a tilt valve. A restricting valve is arranged in an oil passage connecting the tilt cylinder with the tilt valve. When the mast is tilted with the fork carrying an object and located higher than a predetermined reference position, the restricting valve closes the oil passage so that the angle of the tilting mast is limited. A check valve is arranged between the tilt cylinder and the restricting valve. The check valve blocks oil flow from the tilt cylinder to the restricting valve so that the position of the mast is maintained. This prevents unintentional movement of the mast.

Abstract: A tilt control valve controls the flow of hydraulic oil to actuate the tilt cylinders of a forklift mast. The tilt control valve is switched between two positions by the forklift operator by means of a tilt lever. When at one position, the tilt control valve stops flow of oil to the tilt cylinders, thereby prohibiting tilting of the mast. When at the other position, the tilt control valve permits oil flow to the tilt cylinders, thereby allowing tilting of the mast. A control valve is located between the tilt cylinders and the tilt control valve. A seat switch detects whether or not the operator is sitting on the seat. A CPU permits the operator to continue to operate the tilt cylinders to tilt the mast when out of the seat for a brief period. However, after the brief period, the CPU closes the control valve to prevent movement of the mast unless the operator has returned to the seat.

Abstract: An axle tilt control apparatus for forklifts is disclosed. The forklift includes a rear axle pivotally supported by a body frame and a front axle rigidly fixed to the body frame. A mast is supported at the front portion of the body frame to tilt forward and backward. Forks are supported by the mast to be lifted and lowered. The center of gravity of the forklift in the fore-and-aft direction approaches the front axle as the mast is tilted forward. Pivoting of the rear axle is restricted by the hydraulic cylinder when the height of the forks is higher than a predetermined height determination value and the weight of a load on the forks is heavier than a predetermined weight determination value to improve the vehicle's stability. The weight determination value increases as the mast is tilted forward. When a load on the forks is being unloaded, tilting of the rear axle is permitted regardless of the height of the forks and the weight of the load on the forks. Therefore, the rear axle is not unnecessarily locked.

Abstract: A processor implemented stabilization system for load handling equipment monitors at least a portion of the equipment weight load at an equipment support member. Reduction below or increase above predetermined values signals an approaching tip over condition and triggers alarm condition responses for stabilization of the equipment. In a counterbalanced lift truck, the equipment weight load on a rear steer wheel is carried by an outer bearing race of a spindle and is transferred from the race to a load cell which is positioned between the race and a shoulder of a mounting tube. The load cell output is received at a processor which monitors the cell to determine if there is an approaching longitudinal tip over condition (toward or away from the load) as well as a lateral tip over condition.

Abstract: A control is provided for a load-handling device that includes a hydraulic gripper (14) which is intended to grip objects, such as one or more rolls or bales of paper material or other goods, through the medium of pressure in a clamping pressure line (32) leading to one or more hydraulic cylinders (30) that actuate gripping arms on the gripper (14), and on the other hand to lift the objects by actuation from a lifting device (22, 42). The clamping force is adapted to the lifting force during a clamping and lifting operation, by, among other things, monitoring the lifting force of the lifting device (42) with the aid of sensor member. A pressure reduction valve (36) is provided in the clamping pressure line (32), and a control member (50) is provided for controlling the pressure reduction valve (36) to a pressure in the clamping pressure line (36) that is proportional in the lifting force detected by the sensor member (60).

Abstract: The truck mounted lifting mechanism is carried on a truck frame having a pair of opposed C-shaped tracks extending rearward from the cab. A mast having a base carrying an axle engages the outside of the tracks with a pair of flanged rollers. A carriage is mounted at one end on the base axle of the mast. The other end of the carriage is provided with an axle and a pair of flanged rollers which engage the inside of the tracks. The carriage is provided with a threaded central opening and a screw gear extends through the threaded opening and along substantially the entire length of the truck frame. The screw gear is coupled by a chain drive to an hydraulic drive motor. Operation of the drive motor rotates the screw gear causing a lateral displacement of the carriage and the mast between the cab and the rear end of the truck frame. The rear end of the truck frame is provided with a pair of telescoping jacks to stabilize the truck during lifting. The mast is provided with a vertically movable and rotatable fork.

Abstract: An electrical circuit for controlling the tilting of a mast assembly and the lifting of the fork of materials handling vehicles avoids the previously required extra control manipulations while continuing to maintain the safety standards for this type of vehicle. Electromechanical relays or their equivalent are employed to recall whether the tilt limit switch or the height limit switch was first actuated and allows the function associated therewith to continue even though other limit switch is subsequently actuated, thus reducing the number of control operations required during typical vehicle operations. The circuit senses whether both limit switches have been actuated when the vehicle is first powered up, and if so, then one of the limit switches must first be deactuated before either function is permitted to continue either forward or upward, thereby insuring that the vehicle will not be operated beyond predetermined safety limits.

Abstract: When the center of gravity of the load put on the two prongs of a forklift is located to the right or left of the central position, the prongs are tilted. The invention is intended to prevent the prongs from tilting in this situation. Tilt sensors are mounted on the prongs. A computer calculates the tilt angles of the prongs, based on the output signals from the sensors. A driving device receives the output signals from the computer and brings the prongs into the horizontal.

Abstract: A travel speed limiting control system for lift trucks, particularly of the "orderpicker" type, having an extendible mast, is disclosed. The truck travel speed which the operator can command is limited by factors including load weight, load elevation, heading angle and direction of truck travel (forward or reverse) . Optionally, other factors may be involved, such as lateral tilt and load moment. An algorithm including the desired input factors is continually processed by an on-board microcomputer to provide an instantaneous speed limit signal. In addition to its normal operating mode, the microcomputer is also arranged to operate in a "learn" mode, whereby it runs through the ranges of various input signals and develops a set of stored values which indicate the allowable ranges of the inputs, as well as offset or bias values which compensate for manufacturing tolerances occurring in the components of the system.

Abstract: Fork lift truck comprising a chassis, a front and a rear axle supported by the chassis and having wheels at their outer ends, a portal which is pivotally connected to the front of the chassis, a fork, on which a load can be placed, being movable along said portal, an engine which is provided on the chassis for driving wheels of the fork lift truck, said truck being intended for being transported under the loading floor of a vehicle intended for goods carriage. A counterweight is provided outside the wheelbase at the end of the chassis located opposite the portal, whilst the portal is pivotally connected to the chassis in such a manner that the portal can be folded down over the engine and the counterweight against the upper side of the chassis.

Abstract: This invention relates to a cargo-handling vehicle equipped with a cargo-handling apparatus and having a single power plant adapted to commonly drive a hydraulic pump for driving and a hydraulic pump for cargo-handling. A driving command signal in the form of an analog or digital electric signal output from a driving operation device in response to the operated amount thereof is output to first conversion means. The first conversion means converts the driving command signal or the operated amount of the driving operation device to power plant revolution data for driving which is determined by the preset function, and then outputs the data to selection means. A cargo-handling command signal in the form of an analog or digital electric signal output from a cargo-handling operation device in response to the operated amount thereof is output to second conversion means.

Abstract: A control device for loading and unloading mechanism adapted to be incorporated in a fork lift truck comprises a sensor unit 100 including a lifting height sensor 102, a tilting angle sensor 104, and a load sensor 106, a control unit 200 comprising a control command producing circuit 240 constituted by a microcomputer 230 producing a control command on the basis of comparing calculation between the output of the sensor unit 100 and the concerned data stored in the microcomputer 230. The control device further comprises actuators 322, 324 including servomotor driving circuit therein responsive to the control command fed from the control unit 200, and a hydraulic pressure driving circuit 340 for hydraulically controlling a lift cylinder 346 and a tilt cylinder 348 in accordance with the corresponding output of each actuator, respectively. The control device is capable of effecting a automatic running attitude control due to the data stored in the microcomputer 230.

Abstract: A control device for loading and unloading mechanism adapted to be incorporated in a fork lift truck comprises a sensor unit 100 including a lifting height sensor 102 and a load sensor 106, a control unit 200 comprising a control command producing circuit 240 constituted by a microcomputer 230 producing a control command on the basis of comparing calculation between the output of the sensor unit 100 and the concerned data stored in the microcomputer 230, a servomotor driving circuit 322' responsive to the control command indicative of a valve opening angle, and a hydraulic pressure driving circuit 340 for actuating a lift cylinder in accordance with the output of the servomotor driving circuit 322'. The control device is constituted so that, when the work for piling or unloading a load on a shelf is effected based on the stored lifting height data, the two positions required for piling and unloading can be stored in the same address allotted to the corresponding shelf can be stored.

Abstract: A control device for loading and unloading mechanism adapted to be incorporated in a fork lift truck comprises a sensor unit 100 including a lifting height sensor 102, a control unit 200 comprising a control command producing circuit 240 constituted by a microcomputer 230 producing a control command on the basis of comparing calculation between the output of the sensor unit 100 and the concerned data stored in the microcomputer 230, and a driving unit 300 producing a driving output signal so as to the lifting height of the fork 18 in accordance with the control command fed from the control unit 200. The control device includes a component operable for inhibiting storage of sampled lifting height data when the actual lifting height data are not within an allowed range, thereby to prevent erroneous operation based on erroneous data and to effect smooth follow-up speed control to the target height when automatic lifting height control is effected.

Abstract: An improved fork lift truck control system using a microcomputer, which comprises a sensing unit including a first sensor for detecting a lift height of a fork above its lowest position and a second sensor for detecting a tilting angle of an upright with respect to a neutral position of the upright including an input interface circuit for interfacing the sensing unit and control unit which has: (a) a lifting height counting circuit which counts the number of pulses produced on a basis of two photo-converted electrical signals fed from two photocouplers constituting the first sensor, the signals having a phase difference of 90.degree.

Abstract: A method and system for horizontally controlling a fork for a fork lift truck to be positioned at a position parallel with respect to the ground, according to the loads mounted on the fork. The target backward tilting angle of the upright is previously determined as a function of the load on the fork and stored in a memory of a microcomputer. Therefore, the microcomputer outputs an upright forward/backward tilting operation command signals to a tilt servo mechanism on the basis of signals outputted from a load sensor and a potentiometer to detect upright tilt angles. The tilt servo mechanism according to the present invention can adjust and stop the upright at a target backward tilting angle at a low speed without applying a shock to the load.

Abstract: The operator of a lift truck or other load supporting vehicle (11) having a tiltable mast (12, 12a) is alerted as the mast (12, 12a) tilts beyond a predetermined orientation by a temporarily slowing of the rate of tilting movement. Return motion of the mast (12, 12a) may be unimpeded. The operator is reliably made aware when the mast (12, 12a) reaches a predetermined limit but may continue the tilting motion when that is necessary for such purposes as traveling the vehicle (11) under overhead obstructions. In systems where the mast (12, 12a) is tilted by fluid motors (20, 20a), the automatic tilt speed reduction may be realized with a valve (33, 33a) which temporarily introduces a one way flow restriction (49) into the fluid flow path (28, 28a) between the motors (20, 20a) and pressurized fluid source (27, 27a), the valve (33, 33a) being actuated by inclination sensing mechanism (23, 23a).

Abstract: An electronically controlled fork-lift truck having a tilt-cylinder controlled mast and a lift-cylinder controlled fork, comprising a control board mounted adjacent to a driver's seat, the control board having formed thereon various push button switches and a display panel for displaying the heights of the fork, an electronic controller operatively connected with the control board for controlling the movements of the fork and mast, a fork height sensor for detecting the movement of the fork and generating signals denoting increments of that movement, and a tilt sensor for detecting the upright and a tilt-back position of the mast and providing a signal to stop the mast movement wherein the electronic controller can provide various functions including an automatic fork raising and lowering operation.

Abstract: The front and rear sections of the vehicle are normally free to rock relative to one another about a fore-and-aft extending, horizontal axis to the extent necessary to compensate for lateral variations in ground contour between the front and rear of the vehicle. However, when a lift on the front of the vehicle is operated and it reaches a predetermined height, a fluid-pressure circuit is activated to frictionally engage a pair of brake parts on the two sections of the vehicle so as to hold the same against free rocking, thereby making the combined masses of the two sections available to counterbalance any tendency of the lifted load to tip the vehicle over sideways as the load is raised.

Abstract: The invention is concerned with an improvement in a lift truck having a mast assembly, a frame and tilt motor apparatus for tilting the mast assembly forwardly and rearwardly relative to the frame. Particularly the invention is concerned with a lateral support device for the mast assembly. The lateral support device comprises a pair of guides each affixed to a lateral outer surface of the mast assembly and a pair of bearing devices affixed to the frame, each in position to slidably receive a respective one of the guides on operation of the tilt motor apparatus to tilt a top portion of the mast assembly rearwardly to thereby bearingly hold the mast assembly snugly between the pair of bearing devices whereby during movement of the lift truck lateral motion of the mast assembly is restricted when the guides are held between the bearing devices.

Abstract: A fork lift truck has a safety system for inhibiting further raising of the carriage or further forward tilting of the mast when an excessive tilting moment is acting on the truck and permits override of the safety system so that the overload can be relieved by the operator under certain conditions without requiring the assistance of a second truck.