Lifting Device, Such as a Forklift Truck and Pallet Truck, Provided with a Sensor System, and Method Therefor

Abstract

The present invention relates to a lifting device, such as a forklift truck or pallet truck, provided with a sensor system and method therefor. The lifting device includes: a frame; a fork system with a number of forks, connected to the frame; controller configured to detect an undesired bending and/or length of a fork; and a sensor system arranged in or on the fork system and operatively connected to the controller. The sensor system is configured to provide a bending measurement and/or a length measurement of at least one of the forks of the fork system to the controller.

Claims

1. A lifting device, such as a forklift truck or pallet truck, comprising: a frame; a fork system with a number of forks, connected to the frame; a controller configured to detect an undesired bending and/or length of a fork; and a sensor system arranged in or on the fork system and operatively connected to the controller, wherein the sensor system is configured to provide a bending measurement and/or a length measurement of at least one of the forks of the fork system to the controller.

2. The lifting device as claimed in claim 1, wherein the sensor system comprises one or more of an inclinometer and strain gauges for providing the bending measurement of at least one of the forks.

3. The lifting device as claimed in claim 1, wherein the sensor system comprises one or more of a cable transducer, laser, ultrasonic sensor, flow sensor for providing the length measurement of at least one of the forks.

4. The lifting device as claimed in claim 1, wherein the sensor system further comprises a pointing system configured to orient the forks of the fork system.

5. The lifting device as claimed in claim 1, wherein the sensor system further comprises a transmitter and/or transmitter-receiver.

6. The lifting device as claimed in claim 1, wherein the lifting device further comprises a tilting system for correcting the position of the forks in accordance with a bending measured with the sensor system.

7. The lifting device as claimed in claim 1, wherein the forklift truck is provided with a bending controller configured to control the tilting system in automatic manner on the basis of information received from the sensor system.

8. The lifting device as claimed in claim 1, wherein the fork system is provided with a number of extending forks.

9. The lifting device as claimed in claim 1, further comprising an extension controller configured to adjust the length of the extending forks.

10. The lifting device as claimed in claim 1, further comprising a reader configured to read information about dimensions of the cargo to be handled.

11. The lifting device as claimed in claim 1, wherein the sensor system comprises a sensor module provided with a flow meter configured to measure the flow, and an angle measuring device.

12. The lifting device as claimed in claim 1, wherein the fork system is provided with a recess adapted to the sensor system.

13. The lifting device as claimed in claim 1, wherein the recess is arranged in or under an exchangeable wear pad of the fork system.

14. The lifting device as claimed in claim 1, wherein the sensor system is provided with an accumulator.

15. A method for providing measurement information about a fork of a fork system of a lifting device, such as a forklift truck or pallet truck, comprising the steps of: providing a lifting device as claimed in claim 1; determining a length and/or bending of at least one of the forks with the sensor system; and reporting the determined length and/or bending.

16. A lifting device, such as a forklift truck or pallet truck, comprising: a frame; a fork system with a number of forks, connected to the frame; a controller configured to detect an undesired bending and length of a fork; and a sensor system arranged in or on the fork system and operatively connected to the controller, wherein the sensor system is configured to provide a bending measurement and a length measurement of at least one of the forks of the fork system to the controller.

17. The lifting device according to claim 16, wherein the lifting device further comprises a tilting system for correcting the position of the forks in accordance with a bending measured with the sensor system.

18. The lifting device according to claim 16, further comprising a reader configured to read information about dimensions of the cargo to be handled.

19. The lifting device according to claim 16, wherein the fork system is provided with a recess adapted to the sensor system, and wherein the recess is arranged in or under an exchangeable wear pad of the fork system.

20. The lifting device according to claim 16, wherein the sensor system comprises a sensor module provided with a flow meter configured to measure the flow, and an angle measuring device.

Description

[0042] Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which:

[0043] FIG. 1 shows a view of a forklift truck with extendable forks and modular inner fork provided with a sensor system according to the invention;

[0044] FIGS. 2A-D show views of an alternative extendable fork and conventional inner fork in one piece for the lifting device according to the invention;

[0045] FIG. 3 shows a view of a forklift truck with conventional (non-extendable) forks provided with the sensor system according to the invention;

[0046] FIG. 4 shows a view of a pallet truck provided with the sensor system according to the invention; and

[0047] FIGS. 5A-C show a sensor module usable in for instance the forklift truck and/or pallet truck of FIGS. 1-4.

[0048] Forklift truck 2 (FIG. 1) is provided with cab 4, frame 6 and a number of wheels 8. Mast construction 12 is provided on front side 10 of forklift truck 2. In the shown embodiment construction 12 is provided with two guides 14 in which or on which fork board 16 is arranged. Two forks 18 according to the invention are arranged on fork board or connecting element 16.

[0049] Fork 18 consists of a fixed fork part 20. Fixed fork part 20 is provided at a first outer end with a number of mounting points or mounting elements 22 for mounting on element 16. Via a first part 24 oriented substantially vertically during use and bend 26 the fixed fork part 20 transposes into a second part 28 which is substantially horizontal during use. In the shown embodiment second fork part 28 connects to the adjustable fork part 30 which is slidable thereover and functions as outer fork. In the shown embodiment adjustable fork part 30 is provided with first recess 32 for a mode of use with a lengthened fork, and second recess 34 for a mode of use with a shortened fork. A plurality of intermediate recesses are optionally possible for the purpose of thereby realizing further adjustable fork lengths. It is also possible to provide such positions in other ways. Nose element 36 is situated on the front side, i.e. at the free outer end of fork 18. Nose element 36 is inserted under the goods to be picked up.

[0050] In the shown embodiment fixed fork part 20 is provided from two separate parts 24, 28. Close to corner 26 parts 24, 28 are connected by means of connecting element 38, in the shown embodiment a bolt connection. It will be apparent that other connecting means can also be applied. In the shown embodiment a thickened portion is arranged on adjustable outer fork 30 at the position of corner 26 and in the assembled situation. It will be apparent that such a modular system for fixed fork part 20 can in principle be applied to any type of outer fork 30. The combination of outer fork part 30 with a profiled sleeve profile and the modular fixed fork part 20 intensifies the advantages of an application-specific dimensioning of forks 18, which can be manufactured in cost-effective manner by reducing relatively complex production steps and/or increasing the flexibility.

[0051] In the shown embodiment sensor system 40 is provided in extendable fork part 30. Sensor system 40 comprises here one or more sensors in sensor part 42, including one or more of an inclinometer, strain gauges, cable transducer, laser, ultrasonic sensor, flow sensor. It will be apparent here that sensor system 40 can be arranged at other locations and distributed over multiple locations. Flow sensor 42 will thus preferably be arranged in the hydraulic system close to fork board 16, and strain gauges will preferably be arranged in or on vertical part 24. Transmitter-receiver 44 and power supply system 46, for instance embodied as an accumulator or battery, are also provided. Transmitter-receiver 44 communicates via signals 48 with external control system 50, for instance an ERP system. Arranged in cab 4 in the shown embodiment is a control box or interface 52 which is provided in the shown embodiment with bending controller 54 and extension controller 56. Also provided in the shown embodiment is additional sensor blocker 58 for an additional sensor and/or reference point which is operatively connected to the other parts of sensor system 40. In the shown embodiment forklift truck 2 is further provided with laser pointer 60 in or close to nose element 36. Laser pointer 60 is preferably integrated in sensor system 40. Although sensor system 40 operates wirelessly in the shown embodiment, a channel 62 can optionally be provided, for instance with a connecting wire as communication cable between sensor system 40 and control box 52.

[0052] Alternative fork 64 (FIGS. 2A-D) is provided with a fixed fork part 66 and extendable fork part 68 on which nose element 70 is provided. Recess 72 is also arranged, optionally with a cover plate. Fixed fork part 66 is here provided from a vertical part 66a, a substantially horizontal part 66b and a connecting part 66c. Such a fixed fork part 66 is for instance a conventional inner fork. For the extension use is made of drive 74 comprising extension parts 76 with hydraulic piston 78, cylinder head 80 and connecting module 82, whereby a connection to the hydraulic system of forklift truck 4 can for instance be provided. A relative movement can hereby be provided in known manner If desired, it is also possible to provide a manual system in similar manner as described in NL 2011022.

[0053] In an alternative embodiment, sensor system 40 can be applied in forklift truck 84 (FIG. 3) provided with fixed forks 86. The operation of forklift truck 84 is similar to the operation of forklift truck 2 as described above. It is further possible to apply sensor system 108 in pallet truck 88 (FIG. 4). In such an alternative application pallet truck 88 is provided with housing 90 on which arm 92 with handle 94 is provided on a side for the purpose of displacing pallet truck 88. Goods are placed on fork system 96, which has a fixed outer profile part 98 and extendable part 100 which is provided with support wheel 102. Support wheel 102 is situated close to or in nose 104. In the shown embodiment outer sleeve 98 is provided with a profile 106. It will be apparent that other embodiments are also possible according to the invention.

[0054] When goods have to be displaced with lifting device 2, 84, 88, these goods are placed on forks thereof. Information about the length of the forks and/or the bending caused by the goods is transmitted to controller 52 and/or external control system 50 using sensor system 40, 108. If desired, settings of forklift truck 2, 84 or pallet truck 88 are adjusted on the basis of the information obtained with sensor system 40, 108. This allows a user or forklift truck driver to decide to perform corrections, for instance to the tilt angle, him or herself. If desired, this can also be performed in automatic manner. The same applies to the setting of the length of the forks in the case of a length-adjustable fork as shown for forklift truck 2 (FIG. 1).

[0055] External system 50 makes it possible to plan maintenance, to monitor power supply system 46 and to recharge or exchange in timely manner The logistical handling of the goods can also be better tracked, and data about the goods to be displaced can if desired be used by controller 52 for the purpose of setting forklift truck 2, 84 or pallet truck 88.

[0056] Sensor module 110 can be applied in forklift trucks (FIGS. 1 and 3), pallet trucks (FIG. 4), and optionally in other devices. Sensor module 110 (FIGS. 5A-C) comprises housing 112 and cover 114. Housing 112 is provided with housing part 112a and cover 112b. In the shown embodiment flow meter 116 is provided, in the shown version a gear wheel flow meter, with gear wheels 116a, housing 116b, flow path 116c. In the shown embodiment accumulator 118 and PCB 120 are provided under cover 114. The various components are mutually connected and, where necessary, provided with seals. In the shown embodiment PCB 120 is provided with a transmitter/receiver for the purpose of enabling wireless communication with a controller.

[0057] The present invention is by no means limited to the above described preferred embodiments thereof. The rights sought are defined by the following claims, within the scope of which many modifications can be envisaged.