DE102021206411A1 - Automated industrial truck with a load sensor device and a load sensor device - Google Patents

Abstract

The invention relates to an industrial truck (1) for at least partially automated transport of a goods carrier (2), the industrial truck (1) comprising at least the following components: - a loading platform (3) with a loading area (4) on which the goods carrier (2) can be arranged at least partially, - a mechanically actuatable load sensor device (5) which is arranged and set up in such a way that it can detect the presence and correct positioning of the goods carrier (2) on the loading area (4), the load sensor device (5) having a Limit switch (6) and a mechanical flap (7) mounted according to the lever principle for actuating the limit switch (6) as a result of contact of the flap (7) with a correctly positioned goods carrier (2).

Description

The invention relates to an industrial truck for at least partially automated transport of a goods carrier, a load sensor device for a corresponding industrial truck and a method for operating an industrial truck that can be operated at least partially automatically.

At least partially automated or even autonomously operable floor conveyor vehicles are known, these can generally also be referred to as (automated or autonomous) floor conveyor vehicles (English: Automated Guided Vehicles; AGVs for short). Corresponding industrial trucks are defined in EN 1525, for example. In order to be able to transport as safely as possible, the goods to be transported, which are usually stored in a goods carrier (often also referred to as a "dolly" in the area concerned), should be transported as close as possible to the center of gravity of the industrial truck.

In the case of forklift trucks with a raised front structure (relative to the loading area or loading platform), the goods carrier should usually be loaded in such a way that its front end is (as positively as possible) arranged on or at least as close as possible to the rear or the rear end wall of the front structure this is adjacent, whereby tipping over and/or damage to the load (the transported goods in the goods carrier) should be prevented as far as possible in the event of an emergency stop and/or abrupt braking in the direction of travel.

Therefore, for automated operation, which usually also includes automated loading processes, sensors in or on the industrial truck are advantageous, which serve to monitor the correct positioning of the goods carrier on the loading platform as reliably as possible (according to IEC 61508). In this context, non-contact sensors in particular, such as capacitive or inductive loading platform sensors, are often used. A disadvantage of these sensors, however, can be seen in the fact that they can only detect specific materials, such as exclusively metallic goods carriers when using an inductive sensor.

Proceeding from this, the object of the invention is to at least partially solve the disadvantages or problems described in connection with the prior art. In particular, in an industrial truck that can be operated at least partially automatically, detection of a loaded goods carrier should be made possible independently of the material of the goods carrier.

These objects are solved by the features of the respective independent claims. Advantageous configurations result from the dependent claims.

• - eine Ladeplattform mit einer insbesondere in (zumindest auch) vertikaler Richtung bewegbaren Ladefläche, auf welcher der Warenträger zumindest teilweise anordenbar ist,
• - eine mechanisch betätigbare Beladungssensoreinrichtung, die so angeordnet und eingerichtet ist, dass sie ein Vorhandensein und eine korrekte Positionierung des Warenträgers auf der Ladefläche erfassen kann, wobei die Beladungssensoreinrichtung einen Endschalter und eine nach dem Hebelprinzip gelagerte, mechanische Klappe zur Betätigung des Endschalters in Folge eines Kontakts der Klappe mit einem korrekt positionierten Warenträger umfasst.

An industrial truck contributes to this for the at least partially automated transport of a goods carrier, the industrial truck comprising at least the following components:

• - a loading platform with a loading surface that can be moved in particular (at least also) vertically, on which the goods carrier can be arranged at least partially,
• - a mechanically actuable load sensor device, which is arranged and set up in such a way that it can detect the presence and correct positioning of the goods carrier on the loading area, the load sensor device having a limit switch and a mechanical flap mounted according to the lever principle for actuating the limit switch as a result of a Includes contact of the flap with a correctly positioned goods carrier.

In the case of the industrial truck, the specified load sensor device advantageously contributes to the fact that a loaded goods carrier can be detected independently of the material of the goods carrier. In particular, goods carriers made of a wide variety of materials can be identified as reliably as possible in advantageously several operating states of the industrial truck (e.g. driving, unloading and loading). The solution indicated is advantageously simple, cheap to manufacture and/or can be implemented with very few parts. The solution is also advantageously very versatile and can work with different types of goods carriers (KLT boxes, dollies, pallets, lattice boxes, ...), which can each be made of different materials.

The industrial truck can, for example, be one as defined in EN 1525. The industrial truck can be set up for at least partially automated and/or autonomous (driving) operation. The industrial truck usually has a loading platform. Furthermore, the industrial truck can have a front structure. The front structure typically has a (substantially vertical) rear wall towards the loading platform. The industrial truck can also include at least one control unit, which can be set up in particular to carry out a method that is also described here.

The goods carrier can basically be a trolley (in particular a so-called dolly), a crate or box, a Trade a pallet or a lattice box. The goods carrier can preferably be a trolley in and/or on which goods to be transported can be stored, in particular for transport. The goods carrier can be equipped with at least two laterally spaced front wheels and at least two laterally spaced rear wheels. The lateral spacing of these wheels can, for example, be dimensioned in such a way that the goods carrier can be driven under by the industrial truck so that the goods carrier can be loaded onto a loading platform of the industrial truck (by driving underneath). Corresponding goods carriers can also be generally referred to as "dolly". The goods carrier can be formed with or made of metal or with or made of plastic. Preferably, the goods carrier can be formed here with or from plastic (and can still be detected as reliably as possible by means of the mechanical load sensor device).

The industrial truck includes a loading platform with a loading area on which the goods carrier can be arranged at least partially. The loading area can (at least also) be movable in a vertical direction. In other words, this means in particular that the loading platform can be formed in the manner of a lifting platform with a loading surface that can be moved vertically to lift a goods carrier. Alternatively or cumulatively, it would also be conceivable to be suitable for a pick-up process in which the loading area is moved vertically and horizontally at the same time (e.g. in the case of rubble containers on trucks) and/or in which the goods are driven under with an inclined loading area and until they come into contact with the Loading sensor device slides up and / or is pulled up.
In particular, the intended use is not limited to a (purely) vertical load-bearing movement.

The industrial truck also includes a load sensor device that can be actuated mechanically and is arranged and set up in such a way that it can detect the presence and correct positioning of the goods carrier on the loading area. The loading sensor device comprises a limit switch and a mechanical flap mounted according to the lever principle for actuating the limit switch as a result of contact of the flap with a correctly positioned goods carrier. The flap can be formed, for example, with or from metal or with or from plastic. The limit switch can be a mechanical limit switch or an electronic limit switch, for example. The flap can be arranged and configured to cover or protect the limit switch. In particular, the limit switch of the load sensor device can be a limit switch designed in accordance with EN ISO 14119 or, in particular, an electronic switch which meets a corresponding safety requirement level (SIL) in accordance with IEC 61508.

In particular, the loading sensor device can be set up in such a way that it has no external spring. An external spring is understood here to be a spring that would be present externally to the limit switch and/or the flap. In particular, there is no spring external to the limit switch and/or the flap. The force for the automatic return of the limit switch and/or the flap can in particular be brought about exclusively by means of a spring which is arranged in the limit switch or is internal to the limit switch. In other words, this means in particular that the solution described here is not dependent on an external (limit switch) spring that could break during operation. Rather, the return of the flap can be brought about by means of an automatically resetting plunger of the limit switch.

According to an advantageous embodiment, it is proposed that the loading sensor device is arranged on (and/or in) a loading boundary surface of the industrial truck. The loading boundary surface can be, for example, a surface of the rear wall or the rear of the front structure of the industrial truck that points toward the loading area. As a rule, the loading sensor device is arranged in a lower area of the loading boundary surface. The loading boundary surface can form part of the loading platform.

In this context, it is particularly advantageous if a positioning of the goods carrier on the loading area can be limited in a loading direction of the industrial truck by means of the loading delimiting surface. For example, the goods carrier can be driven under with the loading platform until the goods carrier (with its front side) is adjacent to the loading boundary surface. This is particularly advantageous in order to be able to (simultaneously) detect the presence and correct position of the load by means of the load sensor device.

According to a further advantageous embodiment, it is proposed that the industrial truck has a control unit which is set up to release a lifting movement of the loading area only when the presence and correct positioning of the goods carrier on the loading area are detected. For example, a safety logic can be implemented in the control unit, which only allows the loading area to be raised if a goods carrier, in particular that has been correctly placed, is detected. This can advantageously contribute to preventing a product carrier from being lifted at too great a distance from the center of gravity.

According to a further advantageous embodiment, it is proposed that the industrial truck has a control device which is set up to enable driving operation of the industrial truck only when the presence and correct positioning of the goods carrier on the loading area are detected. For example, safety logic can be implemented in the control unit, which only allows the industrial truck to move if a goods carrier, in particular a correctly placed goods carrier, is detected. This can advantageously contribute to preventing a goods carrier that is not correctly positioned from being transported.

According to a further advantageous embodiment, it is proposed that a flap length of the flap is greater than a maximum lifting height of the loading area. In other words, this can also be described in particular in such a way that a length of a lever in the form of the flap or a lever arm length of the flap is greater than a (maximum permissible) load stroke of the loading platform for raising the loading area. This is particularly advantageous when the loading area can be moved vertically relative to the loading sensor device. Advantageously, this configuration can contribute to the loading sensor device still being able to perform its function even when the loading surface is lifted to its maximum height. Alternatively, the loading sensor device can be firmly connected to the loading area and can move vertically with the loading area relative to the goods carrier.

According to a further advantageous embodiment, it is proposed that the flap, in the actuated position, is flush with a loading boundary surface of the industrial truck. In particular, in the operating position, the flap is flush with a loading boundary surface of the industrial truck. In other words, this can also be described in particular in such a way that the flap in the actuated position lies completely in a loading boundary surface of the industrial truck or does not protrude (towards the loading surface) from the loading boundary surface. In other words, this can also be described in particular in such a way that a lever in the form of the flap is flush with a section of the rear wall of the front structure of the industrial truck when it is in the actuated position. This can advantageously contribute to the fact that the flap or the lever can be mechanically protected against damage and/or overloading. This can advantageously contribute to mechanically protecting the limit switch contained in the load sensor device, which is actuated by the flap according to the lever principle, from damage or overload.

According to a further advantageous embodiment, it is proposed that the limit switch be spaced from the loading area in such a way that direct contact between a goods carrier and the limit switch is not possible. In other words, this can also be described in particular in such a way that a limit switch located behind the flap or the lever is set back so far that it cannot be actuated if the flap or the lever is missing.

For example, the limit switch can be arranged at a predefinable (longitudinal) distance from the loading area on the inside in the rear wall and/or the front structure. This advantageously contributes to improving security aspects.

According to a further advantageous embodiment, it is proposed that the flap is mounted on a horizontal pivot axis which is aligned parallel to a loading boundary surface of the industrial truck. The pivot axis is in particular aligned orthogonally to the loading direction. The pivot axis can be arranged, for example, in the lower area of the flap. In this context, the pivot axis can be arranged, for example, in such a way that the flap advantageously falls into a position in which it does not actuate the limit switch even in the unloaded or unactuated state (state without load from a goods carrier that is in particular correctly positioned), in particular due to gravity alone . The pivot axis can also be suitable for pivotally attaching the flap (or the lever) in a sensor receptacle, for example formed by a recess in the rear wall of the front structure.

According to a further aspect, a load sensor device that can be actuated mechanically is proposed, which is suitable for an industrial truck described here. The mechanically actuable loading sensor device can be arranged and set up in such a way that it can detect the presence and correct positioning of a goods carrier on a loading area. The loading sensor device comprises a limit switch and a mechanical flap mounted according to the lever principle for actuating the limit switch as a result of contact of the flap with a correctly positioned goods carrier.

1. a) Positionieren eines Warenträgers auf einer Ladeplattform des Flurförderfahrzeugs,
2. b) Beenden des Positionierens, wenn eine mechanisch betätigbare Beladungssensoreinrichtung des Flurförderfahrzeugs mit einem Endschalter und einer nach dem Hebelprinzip gelagerten, mechanischen Klappe zur Betätigung des Endschalters in Folge eines Kontakts der Klappe mit dem Warenträger eine korrekte Positionierung des Warenträgers auf der Ladefläche erfasst.

According to a further aspect, a method for operating an at least partially automated industrial truck is specified, comprising at least the following steps:

1. a) Positioning a goods carrier on a loading platform of the industrial truck,
2. b) End of positioning when a mechanically actuatable load sensor device of the industrial truck with a limit switch and a mechanical flap mounted according to the lever principle for actuating the limit switch as a result of contact of the flap with the goods carrier detects correct positioning of the goods carrier on the loading area.

The positioning can preferably include an active driving under. Alternatively or cumulatively, positioning may include passively pushing the load open (e.g., by a conveyor belt) and/or placing the load.

1. a) Unterfahren eines Warenträgers mit einer Ladeplattform des Flurförderfahrzeugs, entlang einer Beladungsrichtung, sodass eine Ladefläche der Ladeplattform unterhalb des Warenträgers angeordnet wird,
2. b) Beenden des Unterfahrens, wenn eine mechanisch betätigbare Beladungssensoreinrichtung des Flurförderfahrzeugs mit einem Endschalter und einer nach dem Hebelprinzip gelagerten, mechanischen Klappe zur Betätigung des Endschalters in Folge eines Kontakts der Klappe mit dem Warenträger eine korrekte Positionierung des Warenträgers auf der Ladefläche erfasst,
3. c) (zumindest auch) vertikales Bewegen der Ladefläche zum Anheben des Warenträgers.

According to an advantageous embodiment, a method for operating an industrial truck that can be operated at least partially automatically can be specified, with at least the following steps being carried out automatically by the industrial truck:

1. a) driving under a goods carrier with a loading platform of the industrial truck, along a loading direction, so that a loading area of the loading platform is arranged below the goods carrier,
2. b) ending of driving under when a mechanically actuable load sensor device of the industrial truck with a limit switch and a mechanical flap mounted according to the lever principle for actuating the limit switch as a result of contact of the flap with the goods carrier detects correct positioning of the goods carrier on the loading area,
3. c) (at least also) vertical movement of the loading area to raise the goods carrier.

To carry out the method, steps a), b) and, if appropriate, c) can be carried out, for example, at least once and/or repeatedly in the specified order. The method can be carried out, for example, by means of an industrial truck that is also described here, in particular by means of a control unit of the industrial truck. In the method, at least steps a), b) and c) can advantageously be carried out autonomously by the industrial truck.

Furthermore, in step d), an (optical) driving safety sensor can be switched over, which monitors at least one field in the vicinity of the industrial truck. For this purpose, for example (optical) sensors such as at least one laser scanner can be used to monitor at least one warning field and/or protective field in the vicinity of the industrial truck. If an object, such as a person or part of it, is detected by a safety sensor in a warning field or protective field, the industrial truck has usually come too close to this object, so that the operation of the industrial truck is usually restricted, in particular according to the field and/or the type of the field in which the object was detected is influenced in order to avoid a collision with the object as far as possible. The switching can in particular involve a switching of at least one warning field.

• i) (teil-)autonomer Transport des Warenträgers,
• ii) (zumindest auch) vertikales Bewegen der Ladefläche zum Absenken des Warenträgers,
• iii) Ausfahren unter dem Warenträger entlang der Beladungsrichtung, bis mindestens die Ladeplattform des Flurförderzeuges sich ganzheitlich nicht mehr unterhalb des Warenträgers befindet.

To set down the charge, the following procedure can be used, for example:

• i) (Partially) autonomous transport of the goods carrier,
• ii) (at least also) vertical movement of the loading area to lower the goods carrier,
• iii) Extending under the goods carrier along the loading direction until at least the loading platform of the industrial truck is no longer entirely below the goods carrier.

The details, features and advantageous configurations discussed in connection with the industrial truck can accordingly also occur in the method presented here and vice versa. In this respect, full reference is made to the statements there for a more detailed characterization of the features.

• 1: ein beispielhaftes, hier vorgeschlagenes Flurförderfahrzeug in Draufsicht,
• 2: einen beispielhaften Aufbau einer hier beschriebenen Beladungssensoreinrichtung in perspektivischer Ansicht,
• 3: einen beispielhaften Aufbau einer hier beschriebenen Beladungssensoreinrichtung in Explosionsdarstellung,
• 4: einen beispielhaften Aufbau einer hier beschriebenen Beladungssensoreinrichtung in perspektivischer Ansicht, und
• 5: einen beispielhaften Ablauf des hier vorgestellten Verfahrens.

The solution presented here and its technical environment are explained in more detail below with reference to the figures. It should be pointed out that the invention should not be limited by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and/or findings from other figures and/or the present description. It shows as an example and schematically:

• 1 : an exemplary industrial truck proposed here in top view,
• 2 : an exemplary structure of a load sensor device described here in a perspective view,
• 3 : an exemplary structure of a load sensor device described here in an exploded view,
• 4 : an exemplary structure of a load sensor device described here in a perspective view, and
• 5 : an example of the procedure presented here.

1 shows a schematic top view of an exemplary industrial truck 1 proposed here. The industrial truck 1 is suitable or set up for the at least partially automated transport of a goods carrier 2 . The industrial truck 1 has a loading platform 3 with a loading area 4 that can be moved in the vertical direction, for example, and on which the goods carrier 2 can be arranged at least partially. Furthermore, the industrial truck 1 has a mechanically actuated
Load sensor device 5, which is arranged and set up so that it can detect the presence and correct positioning of the goods carrier 2 on the loading area 4.

For example, the industrial truck 1 has a front structure 13 . The front structure 13 has a rear wall towards the loading platform 2, which can serve here as a loading boundary surface 8, for example. In other words, this means in particular that the industrial truck 1 is loaded with the goods carrier 2 along the loading direction 9 (by correspondingly driving under the goods carrier 2 with the loading platform 3) until the goods carrier 2 reaches the loading boundary surface 8, here the rear wall of the front structure 13 has arrived.

Furthermore, in 1 indicated by way of example that a control device 10 of the industrial truck 1 can be integrated in the front structure 13 . The control unit 10 can be set up to enable a lifting movement of the loading area 4 only when the presence and correct positioning of the goods carrier 2 on the loading area 4 is detected. Furthermore, the control device 10 can be set up to enable driving operation of the industrial truck 1 only when the presence and correct positioning of the goods carrier 2 on the loading area 4 are detected.

2 shows a schematic perspective view of an exemplary structure of a load sensor device 5 described here. It can be seen that the load sensor device 5 includes a limit switch 6 and a mechanical flap 7 mounted according to the lever principle for actuating the limit switch 6 as a result of contact of the flap 7 with a correctly positioned goods carrier 2 . The loading sensor device 5 can be integrated, for example, in the loading boundary surface 8 or the rear wall of the front structure 13 . In this context, the loading sensor device 5 can be arranged, for example, in the area of the lower end of the loading boundary surface 8 or the rear wall of the front structure 13 . For example, the loading sensor device 5 can be arranged in a sensor receptacle 14, which can be part of the loading boundary surface 8 or the rear wall of the front structure 13 or an add-on part thereto.

This represents an example of how the loading sensor device 5 can be arranged on a loading boundary surface 8 of the industrial truck 1 , and if so how. Furthermore, this also represents an example of how positioning of the goods carrier 2 on the loading area 4 in a loading direction 9 of the industrial truck 1 can be limited, if necessary by means of the loading delimiting surface 8 .

3 shows schematically an exemplary structure of a load sensor device 5 described here in an exploded view. The exploded assembly drawing illustrates an example assembly sequence from bottom to top. Accordingly, the assembly concept can advantageously manage with (only) four screws 15, two for each of the components limit switch 6 and flap 7. First, the limit switch 6 and the bracket underneath can be screwed onto a platform (for example the loading platform 3). The flap 7 can then be inserted into an exemplary cylindrical gap below a flap carrier, with the flap 7 being able to be aligned in accordance with its functionality. Finally, these two components can be screwed onto the platform.

In 3 can also be seen that the flap 7 can be mounted on a horizontal pivot axis 12, which can be aligned parallel to a loading boundary surface 8 of the industrial truck 1.

4 shows a schematic perspective view of an exemplary structure of a load sensor device 5 described here. The reference symbols are used uniformly so that reference can be made to the preceding explanations. 4 shows the flap 7 in its operating position. In this context shows 4 for example, that the flap 7 can be flush with a loading boundary surface 8 of the industrial truck 1 in its operating position.

Furthermore, in 4 a flap length 11 of the flap 7 is entered as an example. For example, it can be provided that the flap length 11 of the flap 7 is greater than a maximum lifting height of the loading area 4. Furthermore, it can be provided that the limit switch 6 is spaced from the loading area 4 in such a way that direct contact between a goods carrier 2 and the limit switch 6 is not possible.

5 shows a schematic of an exemplary sequence of the method presented here. The method is used to operate an at least partially automated industrial truck 1. The order of steps a), b) and c) shown in blocks 110, 120 and 130 is an example and can be run through at least once in the order shown to carry out the method, for example will.

In block 110, a goods carrier 2 is positioned on a loading platform 3 of the industrial truck 1 according to step a). is arranged below the goods carrier 2. In block 120, according to step b), the positioning or driving under is terminated when a mechanically actuable load sensor device 5 of the industrial truck 1 with a limit switch 6 and a mechanical flap 7 mounted according to the lever principle for actuating the limit switch 6 as a result of contact of the flap 7 with the goods carrier 2 correct positioning of the goods carrier 2 on the loading area 4 is detected. In block 130, according to step c), an (optional) vertical movement of the loading area 4 for lifting the product carrier 2 can take place. Steps a), b) and c) can be carried out automatically by the industrial truck 1 .

By means of the loading sensor device 5, different types of goods carriers 2 can be detected in an advantageous manner, independently of the material, for example from so-called “dollies” to containers, boxes or crates. The fact that the detection by means of the load sensor device 5 is based on the shape of the goods carrier 2 and not on its material properties contributes in particular to this. This advantage can be combined here in particular with a limit switch 5 in the manner of a mechanical safety switch.

If a goods carrier 2, which is in particular correctly positioned on the loading area 4, exerts a force on the flap 7, the flap 7 rotates. This rotation leads to a longitudinal movement in the limit switch 6, in particular a mechanical one affect. After a certain, predefinable distance, which can depend on the load sensor device 5 and/or its installation situation, the limit switch 6 switches over. A corresponding signal from the limit switch 6 can be used by the controller 10 in order to know that a goods carrier 2, which is in particular correctly positioned, is present on the loading platform 3.

When the goods carrier 2 is removed, the flap 7 returns to its initial positions automatically and/or due to the force of an (internal) spring of the limit switch 6 (and because the contact point is remote from the pivot point). Furthermore, the angle of the flap 7 can be mechanically limited in both directions.

Advantageously, the load detection can be monitored using the load sensor device 5 or the signals from the load sensor device 5 can be evaluated in such a way that a specific performance level (PLr for short), in particular a PLr d according to ISO 13849, can be achieved.

In particular, at least one normally closed contact (NC) can be connected to the control device (PLC or S-PLC), for example depending on which PLr is to be achieved. Depending on ISO 13849, it is preferred to use different monitoring functions in order to achieve an advantageous diagnostic coverage (DC). For example, two contacts (NC) that are as safe as possible can be used to achieve a PLr d. Furthermore, a complementary normally open contact (NO) can be used in order to be able to advantageously detect a cable break and/or to achieve a high DC value. It is also advantageous to use a clock signal to detect incorrect wiring.

• • Die angegebene Beladungserkennung ist kostengünstiger als die üblicherweise verwendeten Sensoren, da sie mit vorteilhaft wenigen Teilen auskommt und die Klappe leicht in Massenproduktion hergestellt werden kann.
• • Die Lösung ist in der Lage, mit den verschiedensten Warenträgern (KLT-Kisten, Dollies, Paletten, Gitterboxen, ...) zu arbeiten, die mit verschiedenen Materialen ausgeführt sein können.
• • Die Lösung ist nicht auf eine externe Feder angewiesen, die brechen könnte.
• • Die Lösung lässt sich durch Veränderung des Schaltpunktes und/oder Kontaktpunktes leicht einstellen (z.B. verschiedene Betriebszustände).
• • Die angegebene Beladungserkennung ist einfach zu montieren und zu integrieren.
• • Das Konzept funktioniert mit verschiedenen Arten von Sicherheitssensoren bzw. Endschaltern (z.B. mechanischer Endschalter, elektronischer Endschalter, ...).
• • Die Klappe kann aus verschiedenen Materialien hergestellt werden (z.B. Kunststoff, Metall), wodurch sie für alle verschiedenen Umwelteinschränkungen (ESD, Lebensmittelindustrie,...) geeignet ist.

The solution described contributes in particular to one or more of the following advantages:

• • The loading detection specified is more cost-effective than the sensors usually used, since it advantageously requires fewer parts and the flap can be easily mass-produced.
• • The solution is able to work with a wide variety of goods carriers (KLT boxes, dollies, pallets, lattice boxes, ...), which can be made of different materials.
• • The solution doesn't rely on an external spring to break.
• • The solution can be easily adjusted by changing the switching point and/or contact point (eg different operating states).
• • The specified load detection is easy to assemble and integrate.
• • The concept works with different types of safety sensors or limit switches (eg mechanical limit switch, electronic limit switch, ...).
• • The damper can be made of different materials (eg plastic, metal), making it suitable for all different environmental constraints (ESD, food industry,...).

Reference List

1

industrial truck

2

goods carrier

3

loading platform

4

truck bed

5

load sensor device

6

limit switch

7

flap

8th

loading boundary surface

9

loading direction

10

control unit

11

flap length

12

pivot axis

13

front structure

14

sensor recording

15

screw

Claims (11)

Industrial truck (1) for at least partially automated transport of a goods carrier (2), wherein the industrial truck (1) comprises at least the following components: - a loading platform (3) with a loading area (4) on which the goods carrier (2) can be arranged at least partially, - a mechanically actuable load sensor device (5), which is arranged and set up in such a way that it can detect the presence and correct positioning of the goods carrier (2) on the loading area (4), the load sensor device (5) having a limit switch (6) and a mechanical flap (7) mounted according to the lever principle for actuating the limit switch (6) as a result of contact of the flap (7) with a correctly positioned goods carrier (2). Industrial truck (1) after claim 1 , wherein the loading sensor device (5) is arranged on a loading boundary surface (8) of the industrial truck (1). Industrial truck (1) after claim 2 , wherein the positioning of the goods carrier (2) on the loading area (4) in a loading direction (9) of the industrial truck (1) can be limited by means of the loading delimiting surface (8). Industrial truck (1) according to one of the preceding claims, with a control unit (10) which is set up to release a lifting movement of the loading area (4) only when the presence and correct positioning of the goods carrier (2) on the loading area (4) is detected. Industrial truck (1) according to one of the preceding claims, with a control unit (10) which is set up to enable driving operation of the industrial truck (1) only when the presence and correct positioning of the goods carrier (2) on the loading area (4) is detected. Industrial truck (1) according to one of the preceding claims, wherein a flap length (11) of the flap (7) is greater than a maximum lifting height of the loading area (4). Industrial truck (1) according to one of the preceding claims, wherein the flap (7) is flush with a loading boundary surface (8) of the industrial truck (1) in the actuated position. Industrial truck (1) according to one of the preceding claims, wherein the limit switch (6) is spaced from the loading area (4) in such a way that direct contact between a goods carrier (2) and the limit switch (6) is not possible. Industrial truck (1) according to one of the preceding claims, wherein the flap (7) is mounted on a horizontal pivot axis (12) which is aligned parallel to a loading boundary surface (8) of the industrial truck (1). Mechanically actuable load sensor device (5) for an industrial truck (1) according to one of the preceding claims, wherein the load sensor device (5) has a limit switch (6) and a mechanical flap (7) mounted according to the lever principle for actuating the limit switch (6) in sequence a contact of the flap (7) with a correctly positioned goods carrier (2). Method for operating an industrial truck (1) that can be operated at least partially automatically, at least the following steps being carried out automatically by the industrial truck (1): a) positioning a goods carrier (2) on a loading platform (3) of the industrial truck (1), b) ending the positioning when a mechanically actuable load sensor device (5) of the industrial truck (1) with a limit switch (6) and a mechanical flap (7) mounted according to the lever principle for actuating the limit switch (6) as a result of contact of the flap (7) detects correct positioning of the goods carrier (2) on the loading area (4) with the goods carrier (2).

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