DE102020100896A1 - Industrial truck and method for controlling an industrial truck - Google Patents

Abstract

Industrial truck with a lifting frame (4), a lifting device (5) and a load handling device (6) arranged movably on the lifting frame (4), the load handling device being movable in the vertical direction by means of the lifting device, with a position sensor (9) which is used for detection a height of the load handling device (6) is formed, with a control device (12) which is connected to the lifting device (5), the position sensor (9) and an actuating device (3), the lifting device (5) by means of the control device (12 ) can be controlled in response to the signals of the at least one position sensor (9), a height of the load-bearing means (6) being stored in the control device (12) as a safe parking position. In order to create an industrial truck in which the load handling device can be brought into the safe parking position in a simple and quick but safe manner, it is provided that the control device (12) controls the lifting device (5) in response to an actuation of the actuating device (3), so that the lifting device moves the load handling device (6) in the direction of the safe parking position until the position sensor (9) indicates that the safe parking position has been reached. The invention also includes a method for controlling an industrial truck.

Description

The present invention relates to an industrial truck with a safety device according to the preamble of claim 1.

Such trucks are from the DE102006051675A1 famous. This document discloses an industrial truck with a lifting frame and a load fork, the height and inclination of the load fork being directly or indirectly measurable by means of sensors. A parking position is stored in a monitoring unit. If, when the vehicle is switched off, the sensors detect that the last determined position of the load fork exceeds a predetermined distance in height or inclination from the parking position, a warning signal is generated. The disadvantage of the present invention is that it takes a lot of effort to bring the vehicle into a safe parking position.

Accordingly, the object of the invention is to create an industrial truck in which the load-handling device is brought into the safe parking position in a simple and quick but safe manner.

This object is achieved by means of the characterizing features of claim 1. The industrial truck according to the invention comprises a control device which is connected to a lifting device, a position sensor and an actuating device, the lifting device being controllable by means of the control device in response to the signals of the at least one position sensor, wherein a height of the load handling device is stored in the control device as a safe parking position. According to the invention it is provided that the control device controls the lifting device in response to an actuation of the actuating device, so that the lifting device moves the load handling device in the direction of the safe parking position until the position sensor indicates that the safe parking position has been reached. In this way, a safe parking position can be automatically approached by actuating an actuating device. The actuation device can be identical to the key switch or a similar type of switch used to turn off the vehicle. In this way, the process of moving the load handling device into the parking position is already initiated by switching off.

In contrast to this, moving the load handling device into the parking position in a vehicle of the prior art requires several steps: After the warning tone, which is emitted by the vehicle if the load fork is not in the parking position, the driver must first sit down again, start the vehicle and then manually carry out several operating steps depending on the current position of the load fork. For example, lowering and tilting of the lifting frame or the load fork may be necessary, the correct sequence of these steps also having to be adhered to since, for example, a completely lowered position of the load fork cannot be achieved with the mast or lifting frame inclined. If such a misalignment is not noticed by the driver, it may happen that such an error would only be noticed by the driver after switching off again and sounding a signal tone, who would then have to restart the vehicle in order to move the fork into the final parking position bring.

The position sensor can be designed to detect the height of the load suspension device in the vertical direction, for example by means of a cable sensor or a piston rod sensor. However, it is also possible that only a single position of the load suspension device can be detected by the position sensor, namely the safe parking position. This can be the case, for example, when the lower stop of the load handling device forms the parking position. In this case, when the lowering function of the hydraulic system of the industrial truck is activated, speed monitoring of the load handling device can be sufficient to determine that the load handling device has been lowered to the maximum. In this case, the position sensor is formed by the speed sensor. Other alternatives are conceivable. For example, a pressure sensor in the hydraulic system could also serve to detect a maximally lowered position of the load-bearing device when it rests on the floor and the hydraulic system is thereby relieved. In this case, the parking position can be determined on the basis of the absolute pressure and / or the pressure change in the hydraulic system. If only a single position of the load suspension device can be detected by the position sensor, the direction of movement of the load suspension device is specified in the control device in order to bring the load suspension device into the safe parking position. If the safe parking position is the maximally lowered position of the load handling device, it is necessary to move the load handling device in the downward direction if the safe parking position is not reached.

In an advantageous embodiment, it is provided that a tilt angle sensor for detecting the inclination of the mast around a horizontal axis and a tilting device is provided for pivoting the mast around a horizontal axis, wherein the control device is connected to the tilt angle sensor and the tilting device that the safe Park position additionally includes a tilting position of the mast and that upon actuation of the actuating element the control device also controls the tilting device so that the tilting device swivels the load handling device in the direction of the safe parking position until the tilt angle sensor indicates that the safe parking position has been reached. In this way, both the correct inclination and the height of the load suspension device are set for the safe parking position. In particular, it can be provided that first the lifting frame is brought into a vertical position or the load handling device, in particular the load fork, into a horizontal position and then the load handling device is lowered to the height corresponding to the safe parking position. The load handling device or the lifting frame can then be tilted again, in particular forwards, so that the load fork rests as flat as possible. Such a process would require several individual operating steps in industrial trucks of the prior art.

In general, the safe parking position can contain height values and inclination values as well as optionally tolerances, the tolerances indicating the accuracy with which the safe parking position is to be set. Alternatively, the height of the load handling device and / or the inclination can be stored as a limit value so that the safe parking position is reached, for example, when the height of the load handling device is less than 10 cm and the inclination relative to the vertical is less than 2 °.

In an advantageous development, it is provided that the actuation of an actuating element can be determined by the control device during the movement process and / or the pivoting process and the movement process and / or pivoting process can be interrupted when the actuation is interrupted by the control device. This ensures that the load handling device is permanently moved under supervision and that the movement process can be interrupted immediately by the driver in an unsafe operating situation. The process can be started by a first control element, for example a key switch, while an interruption is activated by a second control element, for example a dead man's switch. However, the start of the process can also be started by an operating element, which must be kept pressed to maintain the process. When this control element is released, the process can then be interrupted by the control device.

Alternatively or additionally, the process is started by a first operating element and the area of the load handling device, in particular under the load handling device, is monitored by a sensor device so that the control device terminates the process when a person or an object enters this area. Such sensors are known to the person skilled in the art from the prior art and can include, for example, ultrasonic sensors, cameras or laser scanners.

In a further development of the invention it is provided that the control device determines the speed of the industrial truck by means of a sensor and prevents an automatic movement into the parking position at a speed other than zero. In this way, the process can be prevented from starting while the industrial truck is moving, which additionally increases safety.

1. a. Erfassen der Betätigung einer Betätigungsvorrichtung durch eine Steuereinrichtung des Flurförderzeugs,
2. b. Auslesen eines Positionssensors, der zur Detektion von zumindest einer Höhe eines Lastaufnahmemittels des Flurförderzeugs ausgebildet ist, durch die Steuereinrichtung des Flurförderzeugs,
3. c. Ansteuern einer Hubeinrichtung des Flurförderzeugs durch die Steuereinrichtung zur Bewegung des Lastaufnahmemittels des Flurförderzeugs in Richtung einer in der Steuereinrichtung hinterlegten sicheren Parkposition,
4. d. Wiederholtes Durchführen der Schritte b. und c. bis die Signale des Positionssensors das Erreichen einer Höhe entsprechend der sicheren Parkposition anzeigen.

The object is also achieved by a method according to the invention according to independent claim 6 with the steps:

1. a. Detection of the actuation of an actuating device by a control device of the industrial truck,
2. b. Reading of a position sensor, which is designed to detect at least one height of a load handling device of the industrial truck, by the control device of the industrial truck,
3. c. Activation of a lifting device of the industrial truck by the control device for moving the load handling device of the industrial truck in the direction of a safe parking position stored in the control device,
4. d. Repeatedly performing steps b. and c. until the signals from the position sensor indicate that a height corresponding to the safe parking position has been reached.

With regard to the advantages of the method according to the invention, reference is made to the advantages of claim 1.

• e. Auslesen eines Neigewinkelsensors durch die Steuereinrichtung zur Ermittlung des Neigewinkels des Hubgerüstes des Flurförderzeugs um eine horizontale Achse,
• f. Ansteuern einer Neigevorrichtung des Flurförderzeugs mittels der Steuereinrichtung zur Neigung des Hubgerüstes des Flurförderzeugs um die horizontale Achse in Richtung einer in der Steuereinrichtung hinterlegten sicheren Parkposition,
• g. Wiederholtes Durchführen der Schritte e. und f. bis die Signale des Neigewinkelsensors das Erreichen einer Neigung entsprechend der sicheren Parkposition anzeigen.

In an advantageous development, the method additionally comprises the steps

• e. Reading of a tilt angle sensor by the control device to determine the tilt angle of the mast of the industrial truck about a horizontal axis,
• f. controlling a tilting device of the industrial truck by means of the control device to incline the mast of the industrial truck about the horizontal axis in the direction of a safe parking position stored in the control device,
• G. Repeatedly performing steps e. and f. until the signals from the tilt angle sensor indicate that a tilt corresponding to the safe parking position has been reached.

Step e takes place here. -G. after step d. The load handling device is therefore lowered in accordance with the safe parking position, in particular into its lowest position. The load handling device or the lifting frame is then tilted forwards in accordance with the safe parking position, in particular until the load fork of the industrial truck rests as flat as possible. In this case, the parking position includes not only a height of the load handling device but also an inclination of the mast, whereby the inclination of the mast can be measured, for example, in ° relative to the vertical or as the deflection of a tilt cylinder, for example in cm, and stored in the parking position.

• h. Auslesen eines Neigewinkelsensors zur Ermittlung des Neigewinkels des Hubgerüstes des Flurförderzeugs um eine horizontale Achse durch die Steuereinrichtung,
• i. Ansteuern einer Neigevorrichtung des Flurförderzeugs mittels der Steuereinrichtung, zur Neigung des Hubgerüstes des Flurförderzeugs um die horizontale Achse in Richtung einer in der Steuereinrichtung hinterlegten Startposition,
• j. Wiederholtes Durchführen der Schritte h. und i. bis die Signale des Neigewinkelsensors das Erreichen einer Neigung entsprechend der Startposition anzeigen.

It can be provided that in response to the detection of the actuation of the actuating device by the control device, the following steps are initially carried out:

• H. Reading out a tilt angle sensor to determine the tilt angle of the mast of the industrial truck around a horizontal axis by the control device,
• i. Controlling a tilting device of the industrial truck by means of the control device for tilting the lifting frame of the industrial truck about the horizontal axis in the direction of a start position stored in the control device,
• j. Repeat steps h. and i. until the signals from the tilt angle sensor indicate that a tilt corresponding to the starting position has been reached.

It can therefore initially by means of steps h. - j. the mast or the load handling device can be brought into a starting position before the load handling device is lowered into its safe parking position. The starting position of the mast (of the load handling device) is preferably reached with a vertical (horizontal) orientation. Since tilting angles of the lifting frame or of the load handling device are conceivable in which it is not possible to lower the load handling device into its safe parking position, such an initial tilting process is advantageous for setting a defined starting position. In this case, step a takes place first, that is, the detection of the actuation of the actuating device and then steps h. - j. to bring the mast into a vertical position. The starting position can optionally also be set within the scope of a tolerance, for example a few cm or °. The aim here is to first bring the mast into a position that enables the load handling device to be moved into the safe parking position in any case. Then the load handling device is according to step b. - d. moves and finally tilted the mast until the safe parking position is reached, the final tilting can be omitted if the inclination of the mast in the starting position and in the safe parking position are identical. Optionally, it is also possible that, after the actuation device has been actuated, a check is first made to determine whether the start position is already present, possibly within a tolerance of, for example, a few cm or °. If the vertical position of the mast is already sufficient for lowering the load handling device into the safe parking position, steps h. - j. be skipped. If the load handling device is already in the safe parking position, the process can be ended immediately.

In order to ensure that the method is carried out as safely as possible, it can be provided that the method is interrupted when the actuation of the actuating device is terminated. This ensures that the process is permanently monitored by an operator. The method can be started by a first control element, for example a key switch, while an interruption is activated by a second control element, for example a dead man's switch. However, the start of the method can also be started by an operating element which must be kept pressed down to maintain the method. When this control element is released, the process can then be interrupted by the control device.

In addition, it can be provided that if the speed of the industrial truck is not equal to zero, an automatic movement of the load handling device is prevented. Before the start of the method, a query is made as to whether the vehicle is stationary.

In general, the method can be applied to any type of position or movement of a load-bearing device of different types of industrial trucks, i.e. to the height and inclination of the load-bearing device or the lifting frame, but also to sideshift, swivel-push and free-lift movement, with the position in each case by means of a corresponding per se known sensors and actuators is read or set by the control device. The position to be set is stored in the control device as a safe parking position.

As already shown in connection with the inclination setting, the sequence in which the actuators are activated can be defined or certain actuators can also be activated multiple times, for example, as already shown first to set the mast vertical and then to bring it into a defined inclination.

It can also be provided that the movement into the safe parking position is linked to further processes that are usually carried out when leaving the vehicle. In this case, the control device can, for example, automatically activate a parking brake, switch off the vehicle or start the charging process for a battery.

• 1 ein erfindungsgemäßes Flurförderzeug,
• 2 einen schematischen Ablauf des erfindungsgemäßen Verfahrens und
• 3 ein Ablaufdiagramm des erfindungsgemäßen Verfahrens.

Further advantageous refinements emerge from the figures and the description of the figures, here show

• 1 an industrial truck according to the invention,
• 2 a schematic sequence of the method according to the invention and
• 3 a flow chart of the method according to the invention.

An industrial truck according to the invention 1 is in 1 shown. This has a driver's workplace 2 with several controls 3 on. This can be, for example, a lever for controlling hydraulic functions of the vehicle, a steering wheel or a switch for starting the vehicle. The vehicle 1 also has a mast 4th on, which by means of a hydraulic system, which is a hydraulic cylinder 5 includes can be extended and retracted. The industrial truck also has 1 via a load suspension device 6th with a fork back 7th and forks of a load fork 8th . By extending and retracting the mast 4th the height of the load suspension device and the load fork can be changed. Additional actuators for adjusting the height of the load suspension device can be present. The current height of the load suspension device above the ground or relative to a reference height can be determined by means of a position sensor 9 be determined. In addition, the inclination of the mast is relative to the vertical by means of a hydraulic cylinder 10 adaptable and can determine the current inclination based on the measurement data of a tilt angle sensor 11 are recorded. The evaluation of the measurement data and the activation of the vehicle functions are carried out by means of a control device 12th . This is designed in particular the position of the operating elements 3 and the measurement signals from the sensors 9 , 11 and other sensors, such as speed sensors and speed sensors, as well as the hydraulic cylinders 5 , 10 and control other vehicle functions.

For the safe parking of the industrial truck 1 it is now provided that the operator has a fixed control element 3 actuated. This actuation is carried out by the control device 12th determined, whereupon several control steps are carried out in order to bring the load handling device into a safe parking position. This is in the 2 shown. It can, for example, at the time of actuation of the control element 3 the load suspension device 6th are in a raised position and the mast 4th in a reclined position as in step 21 of FIG 2 shown. Before lowering the load handler 6th takes place in step 22nd first a vertical position of the mast 4th , because depending on the inclination, a lowering of the load suspension device 6th in the safe parking position in the current tilt position may not be possible. After determining the vertical position of the mast 4th the control device lowers the load suspension device to the height corresponding to the safe parking position. After this in step 23 is achieved as in step 24 shown a forward tilting of the mast, so that the load handler 6th in its front area, in particular the tips of the fork prongs, rests on the ground.

• - die Positionierung eines Seitenschubs für die sichere Parkposition,
• - die Positionierung eines Freihubs für die sichere Parkposition,
• - die Positionierung eines Schwenkschubs für die sichere Parkposition,
• - das Aktivieren einer Parkbremse,
• - das Abschalten des Fahrzeuges,
• - das Verriegeln des Fahrzeugs,
• - das Starten eines Ladevorganges.

In detail, as in 3 shown, initially in step 30th the control unit interrogates the actuating element used to activate the parking function. This can be, for example, the key switch of the industrial truck, which must be set to "Off" to activate the parking function and switch off the vehicle. Then takes place in step 31 a reading of an engine speed or speed sensor. This value is then used in step 32 determined whether the truck is at a standstill. If there is no standstill, activation of the parking function is prevented by the control unit. By activating the parking function, as already described above, the mast is first set vertically. This is done in step 33 first the angle of inclination is determined and then with a setpoint in step 34 matched. If the angle to the vertical is not equal to 0 °, the lifting frame is repeated using the steps 33 , 34 and 35 pivoted in the direction of the vertical until the vertical position is reached. Then in step 36 the current lifting height is determined in step 37 compared with a target value and the load handling device by means of repeated application of the steps 36 , 37 and 38 moves in the direction of the safe parking position h = 0 until this is reached. This can in particular require lowering the load fork, since the lifting height assigned to the safe parking position is usually in the vicinity or at the maximum lowered position. However, any other lifting height is also conceivable as a safe parking position. Then the tilt of the mast is again in step 39 determined and in step 40 compared to a target value. The steps 39 , 40 and 41 are repeated until the incline assigned to the safe parking position is set. For this purpose, the mast can in particular be inclined a few degrees forward in order to place the load fork of the load suspension device as flat as possible on the ground. When the final parking position is reached, the process is ended in step 42 In principle, moving into the safe parking position can include further method steps. This can be, for example:

• - the positioning of a sideshift for a safe parking position,
• - the positioning of a free stroke for the safe parking position,
• - the positioning of a swiveling thrust for the safe parking position,
• - the activation of a parking brake,
• - switching off the vehicle,
• - locking the vehicle,
• - starting a charging process.

The possible positioning steps can each include an initial movement into a starting position in accordance with the setting of the inclination of the lifting frame, as well as moving it to a final, safe parking position.

List of reference symbols

1

Industrial truck

2

Driver's workplace

3

Control element

4th

Mast

5

Hydraulic cylinder

6th

Load handling equipment

7th

Fork back

8th

Load fork

9

Position sensor

10

Hydraulic cylinder

11

Tilt angle sensor

12th

Control device

21-24

Process flow

30-42

Procedural steps

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102006051675 A1 [0002]

Claims (11)

Industrial truck with a lifting frame (4), a lifting device (5) and a load handling device (6) which is movably arranged on the lifting device (4), the load handling device being movable in the vertical direction by means of the lifting device, with a position sensor (9) which is used for detection is formed from at least one height of the load handling device (6), with a control device (12) which is connected to the lifting device (5), the position sensor (9) and an actuating device (3), the lifting device (5) by means of the control device (12) can be controlled in response to the signals of the at least one position sensor (9), with a height of the load handling device (6) being stored in the control device (12) as a safe parking position, characterized in that the control device (12) reacts to actuation of the actuating device (3) controls the lifting device (5) so that the lifting device moves the load handling device (6) towards the safe parking position position until the position sensor (9) indicates that the safe parking position has been reached. Truck after Claim 1 , characterized in that a tilt angle sensor (11) for detecting the tilt of the mast around a horizontal axis and a tilting device (10) for pivoting the mast (4) around a horizontal axis is also provided, the control device (12) with the tilt angle sensor (11) and the tilting device (10) is connected, that the safe parking position also includes a tilting position of the lifting frame (4) and that when the actuating element (3) is actuated, the control device (12) also controls the tilting device (10) so that the tilting device the load handling device (6) is pivoted in the direction of the safe parking position until the tilt angle sensor (11) indicates that the safe parking position has been reached. Truck after Claim 1 or 2 , characterized in that the actuating element (3) is designed as a push button or switch in the driver's cab of the industrial truck and that the control device (12) moves the load handling device (6) into the safe parking position in response to a defined actuation pattern of the actuating element (3) causes. Truck after one of the Claims 1 - 3 , characterized in that during the movement process and / or the pivoting process, the actuation of an actuating element (3) can be determined by the control device (12) and the movement process and / or pivoting process can be interrupted when the actuation is interrupted by the control device (12). Truck after one of the Claims 1 - 4th , characterized in that the control device (12) determines the speed of the industrial truck (1) by means of a sensor and prevents automatic movement into the parking position at a speed other than zero. Method for controlling an industrial truck, characterized by the process steps a. Detecting the actuation of an actuating device (3) by a control device (12) of the industrial truck (1), b. Reading out a position sensor (9), which is designed to detect at least one height of a load handling device (6) of the industrial truck (1), by the control device (12) of the industrial truck, c. Control of a lifting device (5) of the industrial truck (1) by the control device (12) for moving the load handling device (6) of the industrial truck in the direction of a safe parking position stored in the control device (12), d. Repeatedly performing steps b. and c. until the signals from the position sensor (9) indicate that a height corresponding to the safe parking position has been reached. Procedure according to Claim 6 , characterized by the additional process steps e. Reading of a tilt angle sensor (11) by the control device (12) to determine the tilt angle of the lifting frame (4) of the industrial truck (1) about a horizontal axis, f. Controlling a tilting device (10) of the industrial truck by means of the control device (12) to incline the Lifting frame (4) of the industrial truck about the horizontal axis in the direction of a safe parking position stored in the control device (12), g. Repeatedly performing steps e. and f. until the signals from the tilt angle sensor (11) indicate that a tilt has been reached corresponding to the safe parking position. Procedure according to Claim 6 or 7th In response to the detection of the actuation of the actuating device (3) by the control device (12), the following steps are initially carried out: h. Reading out a tilt angle sensor (11) for determining the tilt angle of the lifting frame of the industrial truck (1) about a horizontal axis by the control device (12), i. Controlling a tilting device (10) of the industrial truck by means of the control device (12) for tilting the mast (4) of the industrial truck (1) about the horizontal axis in the direction of a start position stored in the control device (12), j. Repeat steps h. and i. until the signals from the tilt angle sensor (11) indicate that a tilt corresponding to the starting position has been reached. Procedure according to Claim 8 , characterized in that the starting position corresponds to a vertical position of the mast (4). Method according to one of the Claims 6 - 9 , characterized in that the method is interrupted when the actuation of the actuating device (3) is terminated. Method according to one of the Claims 6 - 10 , characterized in that at a speed of the industrial truck not equal to zero, an automatic movement of the load handling device is prevented.

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