Lift-and-tilt device and method for operating a lift-and-tilt device

Abstract

Lifting and tipping device (100) for a waste collection vehicle with a transport unit (10) having a receptacle for a waste container, a traction element (20) with a first end (22) and a second end (24), and a drive device (50) for lifting the transport unit via the traction element with a drive (52), a gearbox (54), and a drive shaft (56), wherein the transport unit has a deflection pulley (12) for the traction element, the first end of the traction element is attached to a fixed point (60), and the traction element extends from the fixed point to the deflection pulley, around the deflection pulley, and from there to the drive shaft. Furthermore, the invention relates to determining the weight of a waste container by measuring the torque exerted by the drive.

Description

[0001] The present invention relates to a lifting and tilting device and a method for operating a lifting and tilting device.

[0002] Waste collection vehicles are equipped with devices to pick up waste containers and empty their contents into a collection compartment within the vehicle. Generally, the waste containers are first lifted and then tilted during or after the lifting process, so that the contents are emptied through an opening into the collection compartment.

[0003] The waste container is held by a mounting of a transport unit, which is moved up and down by a drive device and has a rotatable pivot shaft. The pivot shaft is raised in the lifting direction by the drive device of the transport unit and rotates about a pivot axis that runs perpendicular to the vehicle's vertical direction, so that the waste container is tilted into an emptying position. Such designs are disclosed, for example, in DE 38 35 748 C1 or WO 2020 / 151849 A1.

[0004] From EP 4 215 459 A1 a lifting and tilting device is further disclosed in which a shaft is rotatably mounted about a pivot axis and a traction element connects the lifting trolley and the drive.

[0005] It can be desirable for various reasons to obtain information about the waste containers to be emptied. Their weight is of particular importance. If a waste container is too heavy for the components of the lifting and tipping device, the device should detect the lifting process as early as possible to prevent damage to the components. To comply with the standard DIN EN 1501-5:2021-05 (Waste collection vehicles - General and safety requirements - Part 5: Tipping mechanisms for waste collection vehicles), the tipping of containers exceeding a specified mass must be prevented.

[0006] Previous attempts to measure the weight of waste containers have yielded unsatisfactory results. It is important to consider that weight measurement should not interrupt or otherwise affect operations. Furthermore, the limited installation space available for lifting and tipping devices presents an additional challenge.

[0007] It is therefore an object of the invention to obtain precise information about a waste container to be emptied, in particular about its weight, before or during an emptying process.

[0008] The problem is solved by the lifting and tilting device according to claim 1. Advantageous embodiments are the subject of the dependent claims.

[0009] The lifting and tilting device comprises a transport unit with a receptacle for a waste container, preferably a guide that directs the transport unit along a lifting direction, a traction element with a first end and a second end, and a drive device for lifting the transport unit via the traction element along the lifting direction. The lifting direction is preferably vertical. The drive device comprises a drive, a gearbox, and a drive shaft, the drive shaft being driven by the drive via the gearbox. The transport unit has a deflection pulley for the traction element; the first end of the traction element is attached to a fixed point, and the traction element extends from the first end to the deflection pulley, around the deflection pulley, and from there to the drive shaft.

[0010] The transport unit is lifted by the drive device. The drive rotates at a preset speed, exerting torque on an input shaft of the gearbox. The gearbox converts the speed and torque and transmits them to an output shaft. The output shaft can be identical to the input shaft or coupled to a separate input shaft. The gearbox's gear ratio i can be defined as the quotient of the output torque and the input torque, or as the quotient of the input speed and the output speed. The applied torque depends on the weight of the transport unit. The greater the weight, the greater the torque. This relationship allows the weight of the transport unit, and thus of the waste container, to be determined from the torque.

[0011] The traction element is coupled to the drive shaft and is thus moved by it, preferably without slippage. The coupling can be achieved, for example, via a drive wheel. When the drive shaft rotates in one direction, the transport unit is lifted by the traction element. The invention is based on the understanding that the torque exerted by the drive depends on the total weight suspended from the traction element. Apart from the weight of the waste container, the total weight of the transport unit is known and largely constant. By measuring the torque of the drive, the weight of the waste container can be determined.

[0012] The losses occurring in a gearbox are not easily and precisely determined and depend, among other things, on the load. These losses lead to imprecise torque measurements. The complexity of the gearbox also influences the magnitude of these losses. According to the invention, a deflection pulley is therefore attached to the drive unit, creating a pulley system. This reduces the load on the gearbox's output shaft compared to a direct connection. Consequently, a gearbox with a lower gear ratio can be used, resulting in a less complex gearbox design and reduced losses. Ultimately, this improves the accuracy of torque measurement and thus the determination of the weight of the waste container or the waste it contains.

[0013] The fixed point is preferably stationary relative to the drive device. Within the lifting and tilting device, the fixed point is then fixed. Rotation of the first end around the fixed point is still possible. The fixed point is preferably located above the traversing unit in its emptying position (upper end position). This ensures that a pulley system is formed in every position of the traversing unit.

[0014] The fixed point can be located, for example, on the housing of the lifting and tilting device or on a bracket. The bracket itself can be part of the guide for the traversing unit. However, it can also be a separate component attached to the housing. It is also possible that the bracket supports other parts of the lifting and tilting device, particularly the drive mechanism.

[0015] The guide preferably comprises two parallel guide rods, each connected at its end by a bridge. The upper bridge can serve as the mounting point. This ensures that the fixed point is located above the end position of the traversing unit. Furthermore, this design utilizes existing components, which is advantageous for maximizing installation space.

[0016] The drive device is also preferably located above an emptying position of the traversing unit.

[0017] A drive wheel is preferably arranged on the drive shaft, rotating with the drive shaft, and the traction element is preferably coupled to the drive wheel. It is particularly advantageous if the drive wheel is a gear and the traction element is a chain. As mentioned above, it is advantageous to avoid losses between the waste container and the drive. The use of a gear and chain results in a positive connection without slippage. Compared to other traction elements, such as a rope and a corresponding friction wheel, this therefore results in fewer losses and a more precise determination of the waste container's weight.

[0018] The chain is preferably a one-dimensionally movable chain (articulated chain) and in particular a roller chain. An articulated chain comprises a plurality of chain links that are rotatably connected to their respective adjacent chain links. The one-dimensional mobility avoids movements of the chain in a second dimension, which could introduce disturbances into the torque determination.

[0019] For precise determination of the waste container's weight, it is crucial that the pulling element is securely held at the fixed point and that no disruptive influences occur there. The chain is therefore preferably connected to the fixed point via a chain holder, which preferably comprises two halves that together accommodate and positively lock several chain links. To ensure a secure hold and absorption of the resulting tensile forces, each half preferably has teeth that project into the gaps in the chain. The teeth of the halves can touch each other when assembled. This completely encloses and securely holds individual chain links. The two halves can, for example, be screwed together to facilitate mounting the chain holder with the chain inside at the fixed point.Alternatively or additionally, the chain holder can also be positively engaged with other components of the lifting-tilting device, for example, a bridge of the guide, whereby the positive engagement is preferably such that the two halves are prevented from falling apart. For this purpose, the chain holder is preferably arranged in a receptacle (of the bridge). The chain holder can also be attached to the fixed point by means of a bolt. For this purpose, each of the two halves can have a bore that is congruent during intended use and accommodates the bolt. The bolt is preferably held by the housing of the lifting-tilting device and particularly preferably passes through two through-holes in the housing. The housing preferably has a reinforcement at each of these through-holes, each of which encompasses a through-hole and is preferably welded to an inner surface of the housing.The reinforcements are preferably flat and preferably have two legs that extend obliquely downwards from the through-hole. This allows the reinforcements to absorb the tensile force of the chain introduced by the bolt very effectively and distribute it evenly into the housing.

[0020] The drive is preferably an electric motor. This allows for easy measurement of the torque exerted by the drive. The gearbox preferably has a gear ratio |i| > 1, which, especially in combination with the electric motor, ensures reliable movement of the transport unit at an appropriate speed. A gear ratio |i| < 50 is preferred, as high losses occur above this ratio, which adversely affect the determination of the waste container's weight.

[0021] The second end of the traction element preferably hangs freely. This second end has only a minor influence on the torque generated at the drive, which is why this arrangement can be chosen for reasons of simplicity. When the output shaft rotates, the second end moves up or down in the opposite direction to the traversing unit without resistance. Due to the use of a deflection pulley, the chain must be lengthened, and the second end of the chain must travel a longer path when the traversing unit moves. The additional chain length makes storage and guidance more difficult. Therefore, the second end can be guided in a hollow tube, preferably one of the guide rods, to prevent it from coming into contact with other components. The lifting and tilting device also preferably includes an insertion device that ensures the traction element is inserted securely and evenly into the hollow tube.The insertion device preferably comprises a ramp that begins below the drive wheel and receives the traction element there. The ramp preferably extends from there to the guide rod. A funnel is preferably provided at the upper end of the guide rod, into which the traction element is fed from the ramp. The funnel preferably has a widened opening at its upper end, which transitions into a narrower guide for the chain. The guide preferably terminates in the guide rod, ensuring that the chain always enters the guide rod cleanly.

[0022] The deflection pulley divides the traction element into two runs, which preferably run parallel to each other. One run extends from the fixed point to the deflection pulley, the second run from the deflection pulley to the drive shaft. This parallel alignment ensures a compact design for the lifting and tilting device. Furthermore, the traction element then runs in a single plane, thus preventing forces acting on the traction element perpendicular to the direction of pull.

[0023] To accurately determine the weight of each waste container, a torque sensor and an evaluation unit connected to the torque sensor are preferably provided. The torque sensor is configured to detect the torque exerted by or applied to the drive. The evaluation unit is configured to determine the weight of the waste container from the torque sensor signal. The torque sensor can be integrated into the drive, particularly if it is an electric motor.

[0024] Within the scope of the invention, it is also possible to provide a pulley system with more than two legs. In this case, more than one deflection pulley is located along the path of the traction element between the fixed point and the drive shaft. These deflection pulleys are then arranged alternately on the traversing unit and in an upper area, for example, on the bridge of the guide. In some embodiments, the fixed point is located on the traversing unit. In a pulley system with three legs, for example, the fixed point is located on the traversing unit. From there, the traction element runs to an upper deflection pulley, which is located, for example, on the bridge, and then to the deflection pulley on the traversing unit, around this deflection pulley, and from there to the drive shaft. Pulley systems with more than two legs allow the gear ratio to be further reduced, thereby further decreasing losses in the gear and thus facilitating a more precise determination of the waste container's weight.

[0025] The object of the invention is also achieved by a waste collection vehicle with a lifting and tipping device as described above.

[0026] The object of the invention is also achieved by a method for operating a lifting and tipping device for a waste collection vehicle, which comprises a transport unit, a traction element, and a drive device for lifting the transport unit via the traction element. The transport unit has a receptacle for a waste container. The traction element has a first end and a second end. The drive device comprises a drive, a gearbox, and a drive shaft, wherein the drive shaft is driven by the drive via the gearbox. In the method, the drive is operated at a predetermined speed, and the torque exerted by the drive is measured. The weight of the waste container is determined from the measured torque. For this purpose, the total weight of the load suspended from the traction element is determined based on the torque, the gear ratio and the associated losses, and the diameter of the drive wheel.Additionally, the number of compartments is taken into account. The known, constant empty weight of the transport unit is subtracted from the weight determined from this calculation. What remains is the weight of the waste container including the waste it contains. The lifting and tipping device preferably has a guide that directs the transport unit along a lifting direction.

[0027] The procedure is preferably carried out using the lifting and tilting device described above.

[0028] The invention is illustrated and explained by way of example with reference to the drawings. The following figures are shown in the drawings: Figure 1: A rear section for a refuse collection vehicle in a rear view. Figure 2: A lifting and tipping device in a photographic position in section from the side. Figure 3: The lifting and tipping device of the Figure 2 In an emptying position, Figure 4 shows a first detail of the lifting and tilting device of the Figure 2Figure 5 shows a second detail of the lifting and tilting device of the Figure 2 Section from the side, Figure 6, the detail of Figure 5 In a perspective view where some parts are shown transparently, Figure 7 shows a chain holder for the lifting and tilting device of the Figure 2

[0029] In the Figure 1 A rear section 300 is shown, which can be attached to the rear of a waste collection vehicle (not shown). The rear section 300 comprises two lifting and tipping devices 100, arranged side by side and mirrored on a central plane. A central receiving opening 200 for tipping waste is provided between the lifting and tipping devices 100. Only the left lifting and tipping device 100 will be discussed in detail below. The right lifting and tipping device 100 is identical in design except for the mirroring.

[0030] The lifting and tilting device 100 comprises a traversing unit 10, a traction element 20, and a drive device 50. The traversing unit 10 has a receptacle 11 for a waste container. A waste container is temporarily positioned at the receptacle 11 for the purpose of emptying it when the traversing unit 10 is in the receptacle position (see Figure 1). Figure 2 The transport unit 10 and the waste container are then raised into an emptying position (see Figure 3 ) and the intake 11 is tilted, whereby the contents of the waste container are emptied through the intake opening 200 into a collection container of the waste collection vehicle.

[0031] In the embodiment shown here, the traction element 20 is a link chain. The traction element 20 comprises two ends, a first end 22 and a second end 24.

[0032] The lifting and tilting device 100 further comprises a guide 40 along which the traversing unit 10 is guided along a lifting direction H. The guide 40 has two guide rods 42 running parallel to each other and to the lifting direction H. The guide rods 42 are each formed by a hollow tube. The guide rods 42 are connected at their upper end to an upper bridge 44 and at their lower end to a lower bridge 45.

[0033] The lifting and tilting device 100 further comprises a drive device 50 for lifting the traversing unit 10 along the lifting direction H via the traction element 20 (see Figure 1The drive device 50 is arranged above the guide 40. It comprises a drive 52 in the form of an electric motor, a gearbox 54, and a drive shaft 56. The drive shaft 56 is driven by the drive 52 via the gearbox 54. A gear, designated as drive wheel 58, is fixedly mounted on the drive shaft 56. The link chain is placed over the gear and engages with it. When the drive shaft 56 rotates, and with it the drive wheel 58, the traction element 20 is moved in one direction or the other.

[0034] The traversing unit 10 has a base body 14 and a deflection roller 12 for the traction element 20, which is rotatably attached to the base body 14 (see Figure 4The deflection pulley 12 is located at the upper end of the base body 14. The deflection pulley 12 is also a gear that engages with the traction element 20. The gear is rotatably mounted on a bolt 13, which is inserted through bores in two lugs 15. The lugs 15 are located on opposite outer sides 16 of the base body 14 and are also rotatably mounted there on a bolt 17. This allows movements of the traction element 20 to be compensated for and prevents the traversing unit 10 from tilting unfavorably in the guide, which could cause it to jam. The base body 14 is tapered in its upper region, and the lugs 15 are essentially flat. This simplifies the manufacturing of the lugs 15.

[0035] The first end 22 of the traction element 20 is attached to a fixed point 60 on the bridge 44. Starting from the fixed point 60, the traction element 20 runs first to the transport unit 10, then around the deflection pulley 12, and from there to the drive shaft 56 of the drive device 50. The deflection pulley 12 divides the traction element 20 into a first section 26 and a second section 28. The first section 26 runs from the fixed point 60 to the deflection pulley 12. The second section 28 runs from the deflection pulley 12 to the drive shaft 56. When the drive shaft 56 rotates in one direction, the second section 28 is moved upwards. The transport unit 10 is thereby moved upwards along the lifting direction H. The first section 26 thus gradually shortens. In this way, the waste container is lifted. A rotation of the drive shaft 56 in the opposite direction leads to a lowering of the travel unit 10 and the waste container.

[0036] The traction element 20 extends from the traversing unit 10, behind the drive wheel 58, into one of the guide rods 42. The other end 24 hangs freely. The lifting and tilting device 100 includes a guide device 80, which ensures that the traction element 20 is inserted securely and evenly into the guide rod 42. The guide device 80 includes a ramp 82 that begins below the drive wheel 58 and receives the traction element 20 there. The ramp 82 extends from there to the guide rod 42, thus at an angle. A funnel 84 is provided at the upper end of the guide rod 42, into which the traction element 20 is inserted from the ramp 82. The funnel 84 has a widened receptacle 86 at its upper end, which transitions into a narrower guide 88 for the chain. The guide 88 ends in the guide rod 42, ensuring that the chain always enters the guide rod 42 cleanly.Even in the lowest position of the traversing unit 10 (receiving position) the second end 24 of the traction element 20 is partially located in the guide rod 42, so that it gradually slides safely into the guide rod 42 during an upward movement of the traversing unit 10.

[0037] The lifting and tilting device 100 comprises a housing 110. The guide 40, the traversing unit 10, and the traction element 20 are arranged within the housing 110. This protects these components from external influences such as rain and dirt. At the same time, it prevents direct access to these components, thus minimizing the risk of injury.

[0038] The Figures 5 and 6 Figure 1 shows the exact connection of the first end 22 to the fixed point 60. In the embodiment shown here, a chain holder 70 is provided (see Figure 2). Figure 7), comprising two halves 72, 74. Both halves 72, 74 have a congruent through-hole 75 at one end, by means of which they are fastened to a bolt 62. The halves 72, 74 interlock. At their other end, the halves 72, 74 have opposing and corresponding teeth 76, 78, which, during normal use, project into the spaces of the link chain. The teeth 76, 78 contact each other and hold the link chain securely in place.

[0039] The two halves 72, 74 are connected to each other by screws. Additionally, the chain holder 70 is positively locked in a receptacle 46 of the bridge 44. Both measures prevent the halves 72, 74 from separating and releasing the chain. The majority of the teeth 76, 78 securely hold the articulated chain, and the load acting on the fixed point 60 is evenly distributed across several chain links of the articulated chain. This reduces the load on the teeth 76, 78 and the individual chain links.

[0040] The bolt 62 passes through two aligned through-holes 112 in the housing 110. Around each of these through-holes 112, the housing 110 has a reinforcement 114, each encompassing a through-hole and welded to the inside of the housing 110. The reinforcements 114 are flat and have two legs 116 that extend obliquely downwards from the through-hole 112. This allows the reinforcements 114 to effectively absorb the tensile force of the chain introduced by the bolt 62 and distribute it evenly into the housing 110.

[0041] Bridge 44 also has a recess 48 for the second span 28. This allows spans 26 and 28 to run parallel to each other and not at an angle to each other. This has the advantage that the tension member 20 runs in a plane and is therefore not subjected to a load perpendicular to the direction of tension. Reference symbol list

[0042] 10. Traverse unit 11. Mount 12. Deflection roller 13. Bolt 14. Base body 15. Tab 16. Outer side 17. Bolt 20 Traction element 22 First end 24 Second end 26 First run 28 Second run 40 Guide 42 Guide rod 44 Upper bridge 45 Lower bridge 46 Mount 48 Recess 50 Drive device 52 Drive 54 Gearbox 56 Drive shaft 58 Drive wheel 60Fixed point 62Bolt 70 Chain holder 72 Half 74 Half 75 Through hole 76 Tooth 78 Tooth 80Infeed device 82Ramp 84Funnel 86Receptacle 88Guide 100 Lifting and tilting device 110 Housing 112 Through hole 114 Reinforcement 116 Leg 200 recording opening 300 rear section H lifting direction

Claims

1. Lifting and tipping device for a waste collection vehicle with a transport unit having a receptacle for a waste container, a traction element with a first end and a second end and a drive device for lifting the transport unit via the traction element with a drive, a gearbox and a drive shaft, characterized by that the transport unit has a deflection pulley for the traction element that the first end of the traction device is attached to a fixed point and that The traction element runs from the fixed point towards the deflection pulley, around the deflection pulley and from there to the drive shaft.

2. Lifting and tilting device according to claim 1, characterized by that the fixed point is arranged on a housing and / or a bracket of the lifting and tilting device, the bracket preferably being part of a guide for the traversing unit.

3. Lifting and tilting device according to one of the preceding claims, characterized by that a drive wheel is arranged on the drive shaft, which rotates with the drive shaft and that the traction element is coupled to the drive wheel.

4. Lifting and tilting device according to one of the preceding claims, characterized by that The drive wheel is a gear and the traction element is a chain.

5. Lifting and tilting device according to one of the preceding claims, characterized by that the chain is connected to the fixed point via a chain holder, wherein the chain holder preferably comprises two halves which together accommodate and positively lock several chain links of the chain between them, wherein the halves are preferably screwed together and / or the chain holder is positively locked by a bridge of the guide.

6. Lifting and tilting device according to claim 5, characterized by thatThe chain holder is attached to the fixed point by means of a bolt, which is preferably held by a housing of the lifting and tilting device, wherein preferably two through holes are provided through which the bolt passes, wherein preferably a reinforcement is provided around each of the two through holes.

7. Lifting and tilting device according to one of the preceding claims, characterized by that The drive is an electric motor.

8. Lifting and tilting device according to one of the preceding claims, characterized by that the gearbox has a gear ratio | i | > 1.

9. Lifting and tilting device according to one of the preceding claims, characterized by that the second end of the traction element hangs freely and / or is guided in a hollow tube.

10. Lifting and tilting device according to one of the preceding claims, characterized byan insertion device for the traction element to safely and uniformly insert the traction element into the hollow tube, wherein the insertion device preferably comprises a ramp and / or a funnel.

11. Lifting and tilting device according to one of the preceding claims, characterized by that The deflection pulley divides the traction element into two sections, which preferably run parallel to each other.

12. Lifting and tilting device according to one of the preceding claims, characterized by that A leading role is provided, which is positioned between the towers and interacts with both towers.

13. Lifting and tilting device according to one of the preceding claims, characterized by a torque sensor configured to detect torque exerted by the drive, and an evaluation device connected to the torque sensor, configured to determine the weight of the waste container from the signal of the torque sensor.

14. Method for operating a lifting and tipping device for a waste collection vehicle, comprising a transport unit having a receptacle for a waste container, a traction element with a first end and a second end, and a drive device for lifting the transport unit via the traction element, comprising a drive, a gearbox, and a drive shaft. characterized by that The drive is operated at a predetermined speed and a torque exerted by the drive is recorded, from which a weight of the waste container is determined.

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