Empty crate inspection by detection of excited oscillations

Abstract

An apparatus for inspecting an empty crate that is transported on a transport device includes an inspection device having a pulse generator, a processor, a sensor, and an uncoupling device. Prior to inspection, the uncoupling device uncouples the empty crate from the transport device. The pulse generator then excites vibrations in the empty crate, which the sensor receives and passes to a processor for analysis.

Claims

1. An apparatus for inspecting empty crates that are transported on a transport device, said apparatus comprising an inspection device, said inspection device comprising a pulse generator, a processor, a sensor, and an uncoupling device, wherein said pulse generator is configured to excite vibrations in an empty crate from said empty crates, wherein said sensor is configured for receiving said vibrations, wherein said sensor is coupled to said processor, and wherein said uncoupling device is configured to uncouple said empty crate from said transport device for inspection of said empty crate.

2. The apparatus of claim 1, wherein said pulse generator comprises a clapper, and wherein said sensor comprises a vibrometer.

3. The apparatus of claim 1, further comprising a stop element, wherein said stop element is movable between a rest position and a stop position.

4. The apparatus of claim 1, wherein said uncoupling device further comprises a support element, and wherein, during inspection thereof, said empty crate stands on said support element.

5. The apparatus of claim 4, wherein said uncoupling device and said support element are disposed in a clearance between conveyor belts of said transport device.

6. The apparatus of claim 1, wherein said uncoupling element comprises a lifting device, wherein said lifting device lifts said empty crate into an inspection position.

7. The apparatus of claim 6, wherein said sensor comprises a laser vibrometer.

8. A method for inspecting an empty crate that is transported on a transport device, said method comprising transferring said empty crate to an inspection position, and inspecting said empty crate only when said empty crate is in said inspection position.

9. The method of claim 8, wherein inspecting said empty crate comprises causing said empty crate to vibrate, recording data representative of said vibrations, and analyzing said data.

10. the method of claim 9, wherein recording data representative of said vibrations comprises using a vibrometer, and wherein causing said empty crate to vibrate includes using a clapper to cause said vibrations.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantageous embodiments of the invention are disclosed in the dependent claims and the following description of the Figures, in which:

(2) FIG. 1 shows a schematic view of an inspection device

(3) FIG. 2 shows a schematic representation of the uncoupling device, and

(4) FIGS. 3-7 shows the individual steps from the entry of the empty crate to its exit from the inspection device.

(5) In the different figures, identical parts are identified by the same reference character.

DETAILED DESCRIPTION

(6) FIG. 1 shows an inspection device 1 for the inspecting of empty crates 2 in which for example drink bottles of any desired materials may be received. The empty crates 2 are transported on a transport device 3. Preferably, the empty crates 2 are plastic empty crates.

(7) The illustrated transport device 3 is of linear design and has two laterally disposed conveyor belts 4 separated from one another by a central clearance 5.

(8) An uncoupling device 6 is disposed in clearance 5. The uncoupling device 6 uncouples an empty crate 2 that is to be inspected from transport device 3. In one embodiment, it does so by lifting the empty crate.

(9) In the particular example shown in FIGS. 1 and 2, the inspection device 1 and the uncoupling device 6 are arranged on an open frame 7. In other embodiments, inspection device 1 together with uncoupling device 6 may also be partially or wholly enclosed.

(10) The uncoupling device 6 has a support element 8 and lifting devices 9 that engage with support element 8 from the latter's underside. In the particular embodiment shown, the lifting devices 9 are lifting cylinders. The lifting devices 9 are connected to a control unit (not shown).

(11) The uncoupling device 6 is advantageously adapted to clearance 5 such that the uncoupling device 6 extends across the clearance with its support element(s) 8 in the raised position so that an empty crate 2 is lifted up from transport device 3.

(12) The inspection device 1 includes elements that excite vibrations in the empty crate 2. The vibrations are captured and evaluated by a sensor or receiver 10. The receiver 10 can be a vibrometer disposed above the empty crate 2. The elements for the excitation of the empty crate 2 can comprise pulse generators, for example clappers, and arranged on the support element 8, or also laterally and/or at the head end, i.e. opposite the base of the empty crate 2.

(13) The inspection device 1 and/or uncoupling device 6 includes stop elements 11 that can be transferred from a rest position 12 (FIG. 6) into a stop position 13 and back. When in their stop position 13, the stop elements 11 each project laterally into the transport path of the transport device 3. When in their rest position 12, the stop elements 11 are swung out of the transport path. The mechanisms for the transition between the rest position 12 and the stop position 13 are conventional enough to not require further description.

(14) A faulty empty crate can be distinguished from a fault-free empty crate by the inspection. If a faulty empty crate is detected, a corresponding signal is generated for separating out the affected empty crate. At a separating device, a crate-pusher conveys the affected empty crate onto a discharge track.

(15) FIGS. 3 to 7 schematically show the individual steps of the empty crate inspection.

(16) In FIG. 3, the empty crate 2 is conveyed on transport device 3 towards inspection device 1.

(17) In FIG. 4, the empty crate 2 reaches an inlet position on the transport device 3 as detected by the control unit by way of corresponding signals. The control unit generates a signal to extend the stop elements 11 out of their rest position 12 and into their stop position 13.

(18) In FIG. 5, The empty crate 2 is held by stop elements 11 in the inspection position in which the empty crate 2 is completely separated and/or lifted up from the transport device 3 by the uncoupling device 6. The empty crate 2 stands on the support element 8.

(19) In the inspection position, vibrations are excited in empty crate 2 and evaluated by the receiver 10. This results in generation of a corresponding signal for distinguishing between a faulty or fault-free empty crate 2.

(20) The empty crate advantageously remains in inspection position 1 for a relatively short period of time so that an inspection capacity of, for example, 3,000 empty crates per hour is achievable. More or fewer empty crates can be inspected.

(21) It is especially expedient that the empty crate 2 be separated, i.e. is lifted up from, the transport device 3 when in the inspection position. This may be detrimental to the attainable inspection capacity, as the empty crate is stopped. But this disadvantage is more than outweighed by the especially reliable inspection result.

(22) Once the inspection has ended, empty crate 2 is set down on the transport device 3 by way of the lifting device 8, the stop elements 11 having first been swung and/or rotated into rest position 12, as shown in FIG. 6. The empty crate 2 is thus transported out of inspection device 1. FIG. 7 depicts how a further empty crate 2 is transported to the inspection device 1.

(23) To facilitate understanding of the invention, the reference numerals used for the various parts described in the figures are summarized in the table below: 1 Inspection device 2 Empty crate 3 Transport device 4 Conveyor belts of 3 5 Clearance between 4 6 Uncoupling device 7 Frame 8 Support element 9 Lifting device 10 Sensor/receiver 11 Stop elements 12 Rest position 13 Stop position