Carrier for a Lifting Device, Lifting Device Provided Therewith and Method Therefor

Abstract

The invention relates to a carrier for a load, such as a fork, a fork board and/or lifting device provided therewith and method for displacing goods. The carrier according to the invention comprises: coupling means configured to couple the carrier to the lifting device; a carrier part for carrying loads, wherein the carrier part is provided with a bend sensor extending over a measurement distance and configured to measure a continuous progression of the bending and/or bending angle occurring substantially over the measurement distance.

Claims

1. A carrier for loads, such as a fork for a lifting device, comprising: coupling means configured to couple the carrier to the lifting device; a carrier part for carrying loads, wherein the carrier part is provided with a bend sensor extending over a measurement distance and configured to measure a continuous progression of the bending and/or bending angle occurring substantially over the measurement distance, and wherein the measurement distance extends over a vertical and/or horizontal part of the carrier part of the carrier.

2. The carrier according to claim 1, wherein the measurement distance extends over at least 10% of the length of the carrier part of the carrier, preferably at least 25%, more preferably at least 40%, still more preferably at least 50%, still more preferably at least 75%, and most preferably at least 90% of the length of the carrier part of the carrier.

3. The carrier according to claim 1, wherein the carrier part is provided over the measurement distance with a groove or recess in which the bend sensor can be at least partially received.

4. The carrier according to claim 1, wherein the measurement distance extends over both a substantially horizontal part and a substantially vertical part of the carrier part of the carrier.

5. The carrier according to claim 1, wherein the sensor comprises an optical fiber cable.

6. The carrier according to claim 1, wherein the sensor further comprises a strain gauge sensor or resistance sensor.

7. The carrier according to claim 1, further comprising a transmitter configured to transmit one or more measurements to a bending controller.

8. The carrier according to claim 7, further comprising an energy source.

9. The carrier according to claim 7, further comprising an alarm for indicating excess stress.

10. (canceled)

11. A lifting device, such as a forklift truck, comprising a carrier and/or fork board according to claim 1.

12. The lifting device according to claim 11, further comprising a bending controller configured to receive a measurement from the bend sensor.

13. A method for measuring a bending and/or bending angle of a carrier, comprising the steps of: providing a carrier according to claim 1; and performing a measurement.

14. The method according to claim 13, further comprising of detecting a plastic deformation with a bending controller.

15. The method Method according to claim 13, further comprising of detecting excess stress with a bending controller.

16. The method according to claim 15, further comprising the step of generating an alarm notification.

17. The method according to claim 13, further comprising of detecting a preventive maintenance moment or maintenance interval.

18. The carrier according to claim 2, wherein the measurement distance extends over both a substantially horizontal part and a substantially vertical part of the carrier part of the carrier.

19. The carrier according to claim 3, wherein the measurement distance extends over both a substantially horizontal part and a substantially vertical part of the carrier part of the carrier.

20. The carrier according to claim 4, wherein the sensor comprises an optical fiber cable.

21. The carrier according to claim 4, further comprising a transmitter configured to transmit one or more measurements to a bending controller and further comprising an energy source.

Description

[0038] 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:

[0039] FIGS. 1A-D show views of the fork with bend sensor according to the invention;

[0040] FIG. 2 shows a forklift truck provided with the fork of FIG. 1;

[0041] FIG. 3 shows a pallet truck provided with the fork of FIG. 1; and

[0042] FIG. 4 shows an AGV provided with the fork of FIG. 1.

[0043] Carrier 2, represented in the shown embodiment as fork 2 (FIGS. 1A-D), is provided with a carrier part 4 which extends substantially in horizontal direction during use and a vertical part 6 which extends substantially in vertical direction during use and on which coupling elements 8, for instance in the form of a hook, are provided. Parts 4, 6 are connected at transition 10, where the so-called heel 12 of fork 2 is provided, optionally provided with wear-limiting elements. In the shown embodiment side 14 of carrier part 4 is provided with groove 16 which extends over substantially the whole (substantially) horizontal length L of carrier part 4 and a part of the (substantially) vertical length L′. In this embodiment the measurement distance of carrier part 4, 6 goes as it were ‘round the bend’. The horizontal length L of carrier part 4 extends between transition 10 and nose 18 at the outer end of fork 2. In the shown embodiment fork 2 is arranged on fork board 3. Fork 2 can relate to a fixed fork 2 (FIG. 1A) and to an extending fork 2 (FIG. 1C). The components and effects described in the context of the present invention apply to both forks 2 and to other types of carrier, including coil booms, crane arms and the like.

[0044] Arranged in groove 16 of carrier part 4, 6 is optical fibre cable 20 which is operatively connected to measurement electronics 22, which in the shown embodiment are arranged in or close to nose 18 of fork 2 (FIGS. 1A and C) and in vertical carrier part 6 (FIG. 1A). Additional sensor element 24 is optionally arranged on or in carrier part 4. It will be apparent that the location of an additional sensor element 24 and/or measurement electronics 22 can be adapted to the sensor in question. Possibly occurring bending (FIG. 1B) of fork 2 is shown schematically. In the shown embodiment optional cover strip or cover plate 21 (FIG. 1D) is provided for the purpose of shielding cable 20.

[0045] Forklift truck 102 (FIG. 2) is provided with cab 104, frame 106 and a number of wheels 108. Provided on front side 110 of forklift truck 102 is mast construction 112. In the shown embodiment construction 112 is provided with two guides 114 in which or on which fork board 116 is arranged. Fork 2 according to the invention is arranged on fork board or connecting element 116. Provided in a possible embodiment is an optionally slidably adjustable fork part (not shown) which functions as outer fork.

[0046] Further provided in the shown embodiment is transmitter-receiver or transmitter 118, as well as energy source or power supply system 120, for instance embodied as an accumulator or battery. Transmitter-receiver 118 communicates via signals 122 with external control system 124, for instance an ERP system. In the shown embodiment control box or interface 126, which is provided in the shown embodiment with bending controller 128 and alarm 130, is alternatively or additionally arranged in cab 104. Also provided in the shown embodiment is additional sensor block 132 for an additional sensor and/or reference point which is operatively connected to other components. In the shown embodiment forklift truck 2 is further provided with laser pointer 134 in or close to nose 18. If desired, a cabled information transfer can additionally or alternatively be provided, for instance by making use of channel/cable 138 between sensor and control box 126.

[0047] Pallet truck 202 (FIG. 3) can likewise be provided with a fork 204 of the type shown in FIG. 1. There is here also a groove 206 in which optical fibre cable 208 is arranged. Fork 2 can also be applied in a so-called AGV 302 (FIG. 4). It will be apparent that components of the various embodiments are interchangeable and/or applicable in other possible embodiments according to the invention.

[0048] When placing goods on fork 2, particularly carrier part 4 thereof, bending of carrier part 4 in particular will occur in the case of a significant load. Due to a change in the signal through optical fibre cable 20, a signal will be determined with the measurement electronics 22, with which signal it has been found possible to determine an exact location of the occurring deformation. Such a measurement can be passed on to an external system 124 and/or control 126 on lifting device 102, 202, 302. If desired, settings of lifting system 102, 202, 302 are adjusted on the basis of the obtained information. It is for instance possible here to envisage the tilt angle. In the case of an extendable fork it is also possible to adjust the length setting. System 124 makes it possible to plan maintenance or perform the necessary monitoring, for instance in respect of wear.

[0049] 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.