WO2019054928A1

WO2019054928A1 - Speed increasing device for a conveyor system

Info

Publication number: WO2019054928A1
Application number: PCT/SE2018/050928
Authority: WO
Inventors: Staffan Robertsson; Hakon Lundberg
Original assignee: Flexlink AB
Current assignee: Flexlink AB
Priority date: 2017-09-13
Filing date: 2018-09-13
Publication date: 2019-03-21
Anticipated expiration: 2020-03-13
Also published as: DE212018000318U1

Abstract

Speed increasing device for a conveyor system where pallets are conveyed with an accumulationchain on a transport plane, comprising a body, a first and a second actuating means, where the first and the second actuating means are adapted to turn a first and a second axle from a first position to a second position, where the first axle comprises a first eccentric end tap and the second axle comprises a second eccentric end tap, and where the speed increasing device comprises a speed rail arranged on the first and the second eccentric end taps, such that the speed rail is configured to be in either a first position or in a second position. The advantage of the invention is that the speed of a conveyor pallet can be increased at predefined positions of the conveyor.

Description

SPEED INCREASING DEVICE FOR A CONVEYOR SYSTEM

TECHNICAL FIELD

The present invention relates to a speed increasing device for a conveyor system comprising accumulation chains. BACKGROUND ART

Conveying devices, such as those which are used for moving objects between different stations in a factory, usually comprise a conveying track in the form of a belt or a chain. The conveying tracks can be recessed in a trench with vertical side surfaces. Alternatively, they can be located on the horizontal upper surfaces of the trench or arranged in some other way. The objects to be conveyed are arranged slidably in relation to the conveying tracks, either directly or via carrying means, which are also known as pallets.

A pallet is conveyed along the conveying device, which comprises different workstations. At a workstation, the pallet can be stopped by a stop member such that an operation may be performed on the transported object. In some cases, the object may pass a specific workstation without an operation being performed on the object. The stop member may for this reason be arranged to either stop the pallet or to let the pallet pass the workstation.

If the conveying device is of a conventional type, in which all workstations are positioned after each other and the operations on the objects are performed synchronous, every pallet will stop at each workstation. If no operation is to be performed on an object at a specific workstation, the object will have to wait until the operation on the previous object at that work station is ready, until the object can continue. All pallets are in this case released at the same time and moves at the same time. One advantage of such a system is that it is easy to predict the performance of the system. One disadvantage of such a system is that it is not very flexible. If the operation time at a work station is long, all objects will have to wait that time, even if there is no operation performed on all objects. Thus, such systems are mostly used for a single product or when the differences in the products are small.

In other systems, the operations on the objects are performed asynchronous, i.e. the pallet stops at a workstation where an operation is to be performed, and is released when the operation is ready. In such systems, a queue comprising a number of pallets may thus be required at at least a few of the workstations in order to compensate for the different through-flow times of the products and for the different operation times at a workstation.

In a conveyor system where the operation time at each workstation differs, it may be of advantage to speed up the pallet at some parts of the conveyor track. It may also be of advantage to speed up the pallet when leaving a workstation, such that a subsequent pallet can enter the workstation earlier. Since the higher speed is only required at some parts of the conveyor track, the speed of the complete conveyor chain cannot be raised. Further, to run the complete conveyor chain with varying speed is complicated and will disturb the flow of the conveyor system. For heavier pallets conveying heavier objects, where the pallets are conveyed by the use of an accumulation chain, one possibility to raise the speed of the conveyor track is to use a speed increasing device that is raised such that the transport rollers abut the speed increasing device. The speed of the conveyed pallet will now be twice the speed of the conveyor track.

The use of a speed increasing device for an accumulation chain is well- known in the art, and is e.g. shown in US 2007034481 A, JP 2010235276 A, US 6244426 B, JP 6080228 A, JP 61267607 A, JP 4148709 A, US 5404997 A and US 5746304 A. Depending on the design of the conveyor system and the conveyor track, different solutions for mounting and operating the speed increasing device are used. One problem in a conveyor system comprising two accumulation chains arranged at each side of the conveyor track, where each accumulation chain is arranged in a conveyor beam, is to mount the speed increasing device in a simple and cost-effective manner in the conveyor beam. In most solutions, the accumulation chain is used in an open arrangement. JP 6080228 A describes a speed increasing device mounted in a conveyor beam which consists of two conveyor beam profiles and which can be split in two parts.

These solutions may work acceptable in some cases. There is however a need for an easier and cheaper way of integrating a speed increasing device in a conveyor beam. There is thus room for improvements.

DISCLOSURE OF INVENTION An object of the invention is therefore to provide a speed increasing device that can easily be integrated in a conveyor beam of a conveyor system. Another object of the invention is to provide a conveyor system comprising at least one speed increasing device integrated in a conveyor beam.

The solution to the problem according to the invention is described in the characterizing part of claim 1 . Claim 1 1 contains an advantageous conveyor system. The other claims contain advantageous embodiments and further developments of the speed increasing device.

In a speed increasing device for a conveyor system where pallets are conveyed with an accumulation chain on a transport plane, comprising a body, a first actuating means and a second actuating means arranged on a first side of body, where the first actuating means and the second actuating means are adapted to simultaneously turn a first axle and a second axle from a first position to a second position, where the first axle and the second axle are arranged through the body, the object of the invention is achieved in that the first axle comprises a first eccentric end tap and that the second axle comprises a second eccentric end tap, when the first eccentric end tap and the second eccentric end tap extend from a second side of the body, and that the speed increasing device comprises a speed rail arranged on the first eccentric end tap and the second eccentric end tap, such that the speed rail is configured to be in either a first position when the first axle and the second axle are in the first position or in a second position when the first axle and the second axle are in the second position.

By this first embodiment of the speed increasing device according to the invention, a speed increasing device that can temporarily raise the speed of a pallet in a conveyor system is provided. The speed increasing device can easily be mounted to a side wall of a conveyor beam without having to dismount the conveyor beam. The speed increasing device is mounted with the first and the second axles extending through two holes in the conveyor beam and is fixed to the conveyor beam by two screws using T- nuts inserted in a groove of the conveyor beam. Since all that is needed to mount the speed increasing device is to drill two holes in the conveyor beam, a speed increasing device can easily be mounted to a conveyor beam without having to dismount the conveyor beam or the conveyor chain. The speed increasing device can further easily be removed from the conveyor beam without having to dismount the conveyor beam. The speed increasing device comprises a speed rail which is configured to be in either a first position or a second position. The speed rail is arranged in the centre of the conveyor beam, between the bearing surfaces for the feed rollers of the accumulation chain. In the first position, the speed rail is in a lower position, in which the upper bearing surface of the speed rail is below the transport rollers of the accumulation chain. In the second position, the upper bearing surface of the speed rail is in a raised position, in which the upper bearing surface abuts the transport rollers of the accumulation chain. The transport rollers of the accumulation chain will now roll on the speed rail, which will cause the speed of the pallet conveyed on the accumulation chain to increase its speed with a factor two, since the speed of the surfaces of the transport rollers will be higher than the speed of the accumulation chain.

Normally, the pallets are conveyed with the speed of the accumulation chain. The feed rollers roll on the bearing surfaces of the conveyor beams, and the pallet bears on the transport rollers that do not rotate. The transport rollers may rotate somewhat when a sudden load change occurs, and will rotate when a pallet is stopped with a stop member. But when the pallet is conveyed, the internal friction in the bearings of the transport rollers will allow the pallet to be conveyed forwards without slippage.

The speed rail is raised and lowered by an actuator. The actuator turns an axle having an eccentric end tap on which the speed rail is arranged. The axle is arranged in a bearing in a body of the speed increasing device. The speed increasing device comprises at least two axles spaced apart which are operated by one or more actuators. In one example, a linear actuator operates two arms connected to the axles, where the arms are connected to each other with a connecting rod. In another example, each axle is provided with a separate drive unit comprising an electric motor. It is also possible to operate both axles with a single motor.

The speed increasing device is mounted to a side wall of the conveyor beam by the use of T-nuts arranged in a groove in the conveyor beam. The axles are inserted through holes that are drilled or routed in the conveyor beam. The holes may be predrilled at predefined positions or may be drilled when needed. When the speed increasing device has been mounted, the speed rail is placed on the axles. In one example, the eccentric end taps are provided with bushings and the speed rail rests on the eccentric end taps with cut-outs in the speed rail.

In on example, the speed increasing device comprises more than two actuating means, i.e. more than two axles acting on the speed rail. In this case, the speed rail can be made longer if the pallet is to be conveyed with a higher speed over a longer distance. It is also possible to position several speed increasing devices next to each other in order to increase the length of the total speed increasing device.

The speed increasing device is intended for heavy duty conveyors comprising accumulation chains as conveying means. In such conveyors, an accumulation chain is arranged on each side of the conveyor. The accumulation chains are moved forwards on the conveyor beams, and the pallet bears on the transport rollers of the accumulation chain and is in this manner conveyed forwards by the rotating feed rollers. This type of conveyor is thus adapted for heavy loads of up to 100 kg and more.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be described in greater detail in the following, with reference to the embodiments that are shown in the attached drawings, in which Fig. 1 shows a front view of a speed increasing device according to the invention,

Fig. 2 shows a rear view of the speed increasing device according to the invention in a first position,

Fig. 3 shows a rear view of the speed increasing device according to the invention in a second position, Fig. 4 shows a development of a speed increasing device according to the invention,

Fig. 5 shows a speed increasing device according to the invention mounted on a conveyor beam,

Fig. 6 shows a cut view of a speed increasing device according to the invention mounted on a conveyor beam, and

Fig. 7 shows a conveyor system comprising two speed increasing devices according to the invention.

MODES FOR CARRYING OUT THE INVENTION The embodiments of the invention with further developments described in the following are to be regarded only as examples and are in no way to limit the scope of the protection provided by the patent claims. References such as longitudinal, horizontal, vertical, right, left etc. refer to directions of a conveyor in normal use. Fig. 1 shows a front view and Figs. 2 and 3 show a rear view of a speed increasing device 1 according to the invention, Fig. 4 shows a development of a speed increasing device, Fig. 5 and 6 show a conveyor beam comprising a speed increasing device and Fig. 7 shows a conveyor system comprising speed increasing devices. The speed increasing device 1 comprises a body 2 having a first actuating means 5 and a second actuating means 6. The first actuating means 5 comprises in a first example a first axle 7 and a first arm 20, and the second actuating means 6 comprises a second axle 8 and a second arm 21 . The first axle 7 is arranged in the body through a first bearing 9 and is provided with a first eccentric end tap 1 1 . The second axle 8 is arranged in the body through a second bearing 10 and is provided with a second eccentric end tap 12. The first axle 7 is adapted to be turned by the first actuating means 5, and will rotate around a first rotational axis 3. The second axle 8 is adapted to be turned by the second actuating means 6, and will rotate around a second rotational axis 4. The first actuating means 5 and the second actuating means 6 are in the shown example identical and are arranged on a first side of the body 2. The first actuating means 5 and the second actuating means 6 are adapted to be actuated simultaneously.

The first eccentric end tap 1 1 of the first axle 7 has a first rotational eccentric axis 13 which is offset from the first rotational axis 3. The first eccentric end tap 1 1 is in the shown example provided with a first bushing 15 which is rotatably arranged on the first end tap. When the first actuating means turns the first axle from the first position 30 to the second position 31 , the first rotational eccentric axis 13 will perform a circular movement from its first position to its second position, which at the same time moves the first rotational eccentric axis 13 upwards.

In the same way, the second eccentric end tap 12 of the second axle 8 has a second rotational eccentric axis 14 which is offset from the second rotational axis 4. The second eccentric end tap 12 is in the shown example provided with a second bushing 16 which is rotatably arranged on the second end tap. When the second actuating means turns the second axle from the first position 30 to the second position 31 , the second rotational eccentric axis 14 will perform a circular movement from its first position to its second position, which at the same time moves the second rotational eccentric axis 14 upwards. When the first rotational eccentric axis 13 and the second rotational eccentric axis 14 are moved upwards at the same time, the speed rail 17 which is resting on the first eccentric end tap 1 1 and the second eccentric end tap 12 is also moved upwards. This will cause the upper bearing surface 19 of the speed rail 17 to come in contact with the transport rollers 46 of an accumulation chain 45 when the speed increasing device is mounted in a conveyor beam. The speed rail is preferably made from a metal, such as steel or aluminium. The transport rollers will start to roll on the upper bearing surface of the speed rail, which in turn will increase the speed of the pallet conveyed by the accumulation chain. In the figures, part of an accumulation chain 45 comprising transport rollers 46 and feed rollers 47 used in a conveyor system is shown.

One advantage with the inventive speed increasing device is that it is a self-contained device that can easily be mounted to an existing conveyor beam without having to disassemble the conveyor system or the conveyor beam. The speed increasing device is mounted to a side wall of a conveyor beam with the axles of the speed increasing device arranged through two holes in the side wall of the conveyor beam. The holes may be drilled when the position of the speed increasing device is decided, or they may be pre-drilled at different predefined positions. In this way, a speed increasing device can easily be mounted to an existing conveyor beam. In the same way, a speed increasing device can easily be removed from a conveyor beam and can be used on another position.

Fig. 2 shows the speed increasing device 1 in the first position 30 where the speed rail 17 is in a lower position and where the upper bearing surface 19 of the speed rail 17 is positioned below the contact plane 48 of the transport rollers. In Fig. 3, the speed increasing device 1 is in the second position 31 where the speed rail 17 is in a raised position where the upper bearing surface 19 of the speed rail 17 coincides with the contact plane 48 such that the bearing surface 19 is in contact with the transport rollers. To reach the second position 31 , the actuator 23 is extended. The actuator may be an air operated cylinder or a linear electric cylinder. Other actuators may also be used, e.g. an electric motor with a transmission. Fig. 4 shows another example of a speed increasing device 1 where the actuating means consists of a first drive unit 24 and a second drive unit 25 arranged on a first side of the body 2. The drive units are here electric motors provided with a transmission connected to the first axle 7 and the second axle 8, respectively. In the shown example, the drive units are identical and are thus mounted with reverse mounting positions. It is also possible to use a single drive unit and connect the first axle and the second axle to each other with pivot arms and a connecting rod. It is also possible to use more than two drive units when a longer speed rail is to be used.

Fig. 5 shows a speed increasing device 1 mounted to a side wall of a conveyor beam 41 , and Fig. 6 shows a cut view of the speed increasing device 1 mounted to a conveyor beam 41 . The speed increasing device 1 is here shown in the second position 31 . The speed increasing device 1 is here mounted to the side wall of a conveyor beam with a second side of the body facing the conveyor beam by the use of screws and T-nuts arranged in a groove in the conveyor beam. The conveyor beam is provided with a first hole 42 and a second hole 43 corresponding to the first axle 7 and the second axle 8, respectively. The speed increasing device is mounted to the conveyor beam such that the first and the second axles extend through the first and the second holes, and such that the first and the second eccentric end taps are positioned at the centre of the conveyor beam, aligned with a centre plane 49 of the conveyor beam. When the speed increasing device is attached to the conveyor beam, the speed rail 17 is placed on the first eccentric end tap 1 1 and the second eccentric end tap 12. The speed rail 17 is provided with semi-circular cutouts 18 which correspond to the eccentric end taps or to the bushings of the eccentric end taps. One cut-out may also be rectangular which may compensate for longitudinal tolerances. More than one speed increasing device may be arranged after each other in a longitudinal direction when the speed of a pallet should be increased for a longer distance. The length of a speed rail may also be varied depending on the requirements. Fig. 7 shows a conveyor system 40 comprising two speed increasing devices 1 mounted on the inner side walls of two conveyor beams 41 . The speed increasing devices are mounted on the same longitudinal position such that the speed of the pallet is increased by both accumulation chains at the same time. The invention is not to be regarded as being limited to the embodiments described above, a number of additional variants and modifications being possible within the scope of the subsequent patent claims. The speed increasing device may have any size and may be made from any suitable material.

REFERENCE SIGNS

1 : Speed increasing device

2: Body

3: First rotational axis

4: Second rotational axis

5: First actuating means

6: Second actuating means

7: First axle

8: Second axle

9: First bearing

10: Second bearing

1 1 : First eccentric end tap

12: Second eccentric end tap

13: First eccentric axis

14: Second eccentric axis

15: First bushing

16: Second bushing

17: Speed rail

18: Cut-out

19: Upper bearing surface

20: First arm

21 : Second arm

22: Connecting rod

23: Actuator

24: First drive unit

25: Second drive unit

30: First position

31 : Second position

40: Conveyor system

41 : Conveyor beam

42: First hole

43: Second hole 44: Pallet

45: Accumulation chain

46: Transport roller

47: Feed roller

48: Transport plane

49: Centre plane

Claims

Speed increasing device (1) for a conveyor system (40) where pallets (44) are conveyed with an accumulation chain (45) on a transport plane (48), comprising a body (2), a first actuating means (5) and a second actuating means (6) arranged on a first side of the body (2), where the first actuating means (5) and the second actuating means (6) are adapted to simultaneously turn a first axle (7) and a second axle (8) from a first position (30) to a second position (31), where the first axle (7) and the second axle (8) are arranged through the body (2)c haracterized in that the first axle (7) comprises a first eccentric end tap (11 ) and that the second axle (8) comprises a second eccentric end tap (12), where the first eccentric end tap (11) and the second eccentric end tap (12) extend from a second side of the body (2), and that the speed increasing device (1) comprises a speed rail (17) arranged on the first eccentric end tap (11) and the second eccentric end tap (12), such that the speed rail (17) is configured to be in either a first position (30) when the first axle (7) and the second axle (8) are in the first position (30) or in a second position (31) when the first axle (7) and the second axle (8) are in the second position (31).

Speed increasing device according to claim 1, characterized in that the first axle (7) is arranged in the body (2) with a first bearing (9), and where the second axle (8) is arranged in the body (2) with a second bearing (10).

3. Speed increasing device according to any of claim 1 or 2, characterized in that the first eccentric end tap (11 ) comprises a first bushing (15) and the second eccentric end tap (12) comprises a second bushing (16).

Speed increasing device according to any of claims 1 to 3, characterized in that the first actuating means (5) comprises a first arm (20), that the second actuating means (6) comprises a second arm (21), and that the first arm (20) and the second arm (21) are interconnected by a connecting rod (22).

Speed increasing device according to claim 4, characterized in that the first actuating means (5) and the second actuating means (5) are operated by an actuator (23).

Speed increasing device according to claim 5, characterized in that the actuator (23) is a linear actuator.

Speed increasing device according to any of claims 1 to 3, characterized in that the first actuating means (5) comprises a first drive unit (24) and that the second actuating means (6) comprises a second drive unit (25).

Speed increasing device according to any of the preceding claims, characterized in that the speed increasing device (1 ) is adapted to be attached to a side wall of a conveyor beam (41), where the first axle (7) is adapted to extend through a first hole (42) in the conveyor beam, where the second axle (8) is adapted to extend through a second hole (43) in the conveyor beam, and where the first eccentric end tap (11 ) and the second eccentric end tap (12) are adapted to be positioned at a centre plane (49) of the conveyor beam (41).

9. Conveyor system (40) adapted to convey pallets (44) on a transporting plane (48), comprising a plurality of conveyor beams (41) and a plurality of accumulation chains (45), characterized in that the conveyor system (40) comprises a plurality of speed increasing devices (1) according to any of claims 1 to 8, where each speed increasing device (1) is mounted to a side wall of a conveyor beam (41 ) with the first axle (7) and the second axle (8) extending through a first hole (42) respectively a second hole (43) in the conveyor beam.