Refrigerated vehicle arrangement and device for operating a generator

Description

[0001] The invention relates to a refrigerated vehicle arrangement, in particular a trailer or semi-trailer provided with a refrigerated compartment, and a device for operating a generator.

[0002] It is generally known from the state of the art that refrigerated vehicles are equipped with refrigeration units to cool the cargo space. Refrigerated vehicles designed as trucks or small vans often have the refrigeration unit connected to the vehicle engine, so that it does not require a separate drive when in motion. When stationary, it can also be supplied with power from a diesel generator or a battery.

[0003] The latter option, for example, was described in detail in DE 10 2017 115 764 A1. This document states, among other things, that a generator is provided for generating electrical energy, which is set in rotation by a rotating shaft driven by the movement of the refrigerated vehicle via a wheel. The energy delivered at the generator output can be fed directly to the refrigeration unit via a buffer storage tank or to a battery.

[0004] A separate drive for the refrigeration unit is particularly advantageous for towed units such as trailers or semi-trailers. However, the diesel engines used for this purpose, which usually power the refrigeration unit, are not subject to the current emissions standards for vehicles within the European Union, meaning that without appropriate exhaust gas aftertreatment they emit significantly higher levels of pollutants. The reason for this is that the EU regulation for small engines does not yet regulate exhaust gases and noise as strictly as it does for vehicle engines. For this reason, the noise level of these diesel units is very high due to the almost or completely uninsulated diesel engine. Therefore, most refrigeration units with a diesel unit also have the option of operating the refrigeration unit with an electric motor when stationary.

[0005] Laying an electrical or additional supply line from the towing vehicle to the trailer is often not possible, as the operator also wants to retain the option of uncoupling the trailer and occasionally swapping a tractor unit. Even in so-called "next-door traffic," where two vehicles approach each other from opposite directions and swap trailers or semi-trailers at the meeting point before returning to their starting point, providing additional supply lines between the towing vehicle and the trailer or semi-trailer is hardly possible in practice.

[0006] For this reason, corresponding battery systems have been developed in recent years. These supply energy to the electric motor of the trailer's or semi-trailer's refrigeration unit and are attached directly to the trailer or semi-trailer. However, due to the highly variable operating times in freight transport, the dimensioning of such battery systems is not easy, as reliable forecasting is almost impossible. International freight forwarders in particular have difficulty finding suitable charging stations for charging the battery systems. In addition, there are hardly enough charging stations at many truck rest areas across Europe to charge the battery systems. Charging the battery system itself is very time-consuming and does not always fit into the freight forwarder's schedule. Therefore, the obvious solution of additionally increasing the capacity of the battery system is often chosen, but this incurs additional costs and additional weight.

[0007] EP 2 266 831 A2 discloses a power generation system comprising an axle shorter than the vehicle's width, two wheels, a shaft, a generator, and a suspension. The wheels are connected via the shaft to the generator, which in turn is mounted on the suspension. The suspension is located on the underside of a refrigerated vehicle body, so that the wheel of the power generation system is driven while driving.

[0008] US Pat. No. 8,723,344 B1 discloses a power generation system in which rotational energy is tapped from a main wire via an auxiliary wheel. For this purpose, the auxiliary wheel contacts the main wheel of the vehicle body. From the auxiliary wheel, the rotational energy is then transmitted via a belt drive to a generator, where electrical energy is generated.

[0009] WO 2006 / 045 124 A1 describes a refrigerated vehicle trailer comprising a belt arrangement connected to the trailer's axle for generating electrical energy while driving or for operating a refrigeration compressor while driving. The belt arrangement is mounted between a generator and the vehicle axle via a transmission and guide wheels, as well as tensioners.

[0010] In US 2012 / 152,634 A1, a fifth wheel for a passenger vehicle is proposed, via which rotational energy is transmitted via a belt to a generator for generating electrical energy while driving.

[0011] From WO 2010 / 133 863 A2, an energy generation system for installation beneath a vehicle body is known, which comprises a wheel driven during travel, the rotational energy of which is transmitted, for example via a chain drive, to a generator for generating electrical energy.

[0012] From US 8,439,140 B1 an adapter is known which is mounted on a vehicle axle of a motor vehicle and which drives a generator via a belt so that rotational energy is transferred from the axle of the motor vehicle to the generator while driving.

[0013] US 2017 / 144,552 A1 describes an energy recovery device for an electric vehicle, which comprises a chain that engages with a sprocket on the rear axle of a motor vehicle and transfers rotational energy to a generator.

[0014] US 5,921,334 A discloses a road generator for a motor vehicle having a generator unit for converting mechanical energy into electrical energy. A structure connects the generator unit to a rear portion of a chassis of the motor vehicle. A wheel assembly is coupled to the connecting structure so that the wheel assembly can rotate on a road on which the motor vehicle travels. A device extends between the generator unit and the wheel assembly to operate the generator unit through the rotation of the wheel assembly on the road. The generator unit can supply power to various electrical components within the motor vehicle.

[0015] US 2016 / 347173 A1 discloses a wheel-driven generator-charging system that captures the rotational energy of a vehicle wheel and transfers it to a generator to generate electricity. An alternator, a bracket, and a transmission shaft are mounted on a support frame. A drive wheel is connected to an existing wheel of the vehicle. The drive wheel is connected to the transmission shaft via a first pulley assembly. A second pulley assembly is connected between the transmission shaft and an alternator wheel. When the vehicle wheel rotates, the mechanical energy is transferred to the alternator via the first pulley assembly, the transmission shaft, and the second pulley assembly. The bracket is attached to the vehicle frame.

[0016] GB 2 156 291 A shows an electrically powered vehicle with a wheel attached to a retractable trailing arm that is lowered to the ground when the vehicle is in motion. The wheel is arranged to drive a flywheel containing a centrifugal clutch that engages means for driving a generator for charging the vehicle's batteries.

[0017] For towed units such as trailers or semi-trailers, separate devices for supplying energy while driving are known, but for various reasons these have not yet been able to prevail in practice.

[0018] However, if the vehicle axles are connected to generators, various electronic assistance systems, such as the legally required anti-lock braking system or the electronic stability program of the towed units, must be readjusted, making any retrofitting time-consuming and costly. Furthermore, with integrated axle generators, adaptation to the battery system being supplied is virtually impossible.

[0019] Furthermore, such devices are subject to increased wear, as they are partly part of the axle as an unsprung mass and are therefore exposed to increased vibrations. Furthermore, these devices are exposed to strong environmental influences during driving.

[0020] Based on this state of the art, the inventor has now set himself the task of creating a refrigerated vehicle arrangement in which a separate battery feed is provided for a towed unit, which can also be easily used in existing towed units and which can be adapted to the requirements of the respective battery system.

[0021] This object is achieved by the features of claims 1 and 6. Further advantageous embodiments of the invention are the subject of the subclaims. These can be combined with one another in a technologically expedient manner. The description, particularly in conjunction with the drawings, further characterizes and specifies the invention.

[0022] According to the invention, a refrigerated vehicle arrangement, in particular a towed unit provided with a cooling chamber, such as a trailer or a semi-trailer, is specified, which has a half-axle provided with a running wheel, which is connected to the vehicle frame via a pivot lever and a bracket arranged on an underside of a vehicle frame, wherein the pivot lever is pivotable about a pivot axis at the end facing the bracket and is provided with a pulley rotatable about the pivot axis, which pulley is driven by the running wheel via a first belt and which drives a generator via a second belt, which is fastened to the vehicle frame and is provided for supplying electrical energy to a battery for supplying a refrigeration unit, wherein the running wheel is arranged in a central region with respect to a longitudinal axis of the vehicle frame and at or adjacent to a slip-free position of the towed unit.

[0023] Accordingly, for towed units such as trailers and semi-trailers, a separate energy supply to the battery is created while driving. According to the invention, the generator is arranged on the vehicle frame of the trailer or semi-trailer so that it is no longer part of the axle of the towed unit and therefore no longer acts as an unsprung mass. Furthermore, the solution according to the invention enables easy adaptation to the respective battery system to be supplied, since only the power output of the generator needs to be selected accordingly. The running wheel operates independently of the other running axles of the towed unit and is subject to only minimal wear due to its advantageous positioning at or adjacent to the no-slip position. For a trailer with a tandem axle, the no-slip position would be between the two axles.In a semi-trailer with three axles, the slip-free position is located close to the center axle. Furthermore, the impeller is mounted approximately in the center of the vehicle, so that any restoring torques caused by the generator's startup are evenly distributed between the left and right wheels of the vehicle axles. The latter feature of the inventive solution proves to be particularly advantageous, as the generator can now be operated in such a way that it can be switched on or off independently of the driving situation, load, and road conditions, without the restoring torques generating sensor signals in the assistance systems, which could trigger reactions in the anti-lock braking system or the electronic stability program that could negatively impact driving performance.The generator can therefore, for example, only be used when the vehicle is moving above a certain speed or can be switched on when requested by the on-board electronics.

[0024] According to embodiments of the invention, the generator can operate the cooling unit directly or be connected to a battery via which the cooling unit is supplied with electrical energy.

[0025] The invention can be used both for direct operation of the cooling unit and for buffering the electrical energy by means of a battery.

[0026] According to a further embodiment of the invention, the generator is controlled such that the output of electrical energy occurs during a coasting operation of the refrigerated vehicle arrangement.

[0027] This ensures that the battery is charged with electrical energy, which would otherwise be wasted as excess braking energy. The information that the semi-trailer or trailer is operating in recuperation mode, for example, when driving downhill, can be detected in various ways. In addition to a simple inclination sensor, which may be coupled with a speedometer, information from a navigation device can also be used, which can link the vehicle's current position to the route profile.

[0028] According to a further embodiment of the invention, the generator is displaceable relative to the pulley for length adjustment to the second belt.

[0029] Since the pivot point of the pulley is identical to the pivot axis of the pivot lever, no additional one-sided tension is exerted on the first belt when the pivot lever is pivoted, ensuring that the first belt remains taut during operation. However, to enable application of the invention to different body types, it has proven useful to compensate for any design-related differences in the positioning of the generator by means of an adjustment mechanism at the length of the second belt. This also facilitates the replacement of the generator, for example, when switching to a more powerful model.

[0030] Both the first belt and the second belt can be equipped with a belt tensioner to keep the belts in the working area.

[0031] According to a further embodiment of the invention, the wheel can be moved from or into a rest position without contact with the road surface.

[0032] In this way, tire wear on the impeller can be reduced, whereby transferring from or to the rest position should also be possible during driving, as already explained above in connection with the activation of the generator, so that the impeller only comes into contact with the road surface above a certain driving speed or in a certain driving situation.

[0033] According to a further embodiment of the invention, the impeller is transferred from or into the rest position by means of a control device, so that the generator delivers electrical energy depending on a power requirement of the cooling unit or a charging requirement of the battery.

[0034] As long as the vehicle's battery does not require charging or the cooling unit does not require power, the wheel can remain in its rest position, so that no additional wear occurs on the wheel's tire.

[0035] According to a further embodiment of the invention, a working cylinder rotates the pivot lever about the pivot axis or a lifting device moves the holder relative to the vehicle frame.

[0036] The pivot lever can be moved in various ways, with the working cylinder being pneumatic, hydraulic, or even using an electric motor. It is also conceivable to move the bracket vertically relative to the vehicle frame using a lifting device instead of moving it around the pivot axis.

[0037] According to a further embodiment of the invention, the pulley has different outer diameters on the running surfaces of the first belt and the second belt.

[0038] The pulley can provide a desired gear ratio by selecting the outer diameter for the belt, so that the use of a gearbox is not necessary.

[0039] According to a further embodiment of the invention, the impeller has a smaller diameter compared to the wheels of the towed unit.

[0040] Compared to the wheels commonly used on trailers or semi-trailers, the road wheel can be equipped with a smaller diameter, although the road wheel should not be smaller than a certain minimum diameter to prevent road obstacles from damaging the road wheel.

[0041] According to a further embodiment of the invention, the refrigerated vehicle arrangement is attached to the vehicle frame as part of a retrofit, in particular via subsequently attached cross members.

[0042] A further advantage is that the solution according to the invention can be quickly assembled and disassembled as a retrofit.

[0043] According to a further embodiment of the invention, the pivot lever is provided in the form of a rocker with a spring element or in which a torsion spring is arranged in the region of the pivot axis.

[0044] To compensate for uneven road surfaces, the pivot lever can be sprung in various ways. It's also important that the wheel is attached to the pivot lever via the shortest possible axle tube to keep the distance to the pivot lever as short as possible, thus minimizing tire wear when cornering due to horizontal bending of the frame.

[0045] Furthermore, a device for operating a generator is specified, which provides an energy supply to a towed unit, such as a trailer or a semi-trailer, wherein the device has a half-axle provided with a running wheel, which is connected to the vehicle frame via a pivot lever and a bracket arranged on an underside of a vehicle frame, wherein the pivot lever is pivotable about a pivot axis at the end facing the bracket and is provided with a pulley rotatable about the pivot axis, which pulley is driven by the running wheel via a first belt and which drives a generator via a second belt, which is fastened to the vehicle frame and is provided for outputting electrical energy, wherein the running wheel is arranged in a central region with respect to a longitudinal axis of the vehicle frame and at or adjacent to a slip-free position of the towed unit.

[0046] In the device for operating a generator, the generator can, if necessary, be connected to a battery system, as already described above in connection with the supply of a cooling system on a trailer or semi-trailer. However, the device can also supply other units on a trailer or semi-trailer with energy. Other applications would be, for example, the supply of pumps or agitators on a tank trailer, or an electric or hydraulic drive of a rotating and tiltable mixing drum on a concrete mixer via an electric motor. In the following detailed description, only the application is described with reference to a room to be cooled, without, however, limiting the invention to this case.

[0047] Below, some examples are explained in more detail using the drawings. They show: Figure 1 shows a side view of a refrigerated vehicle arrangement according to the invention, Figure 2 shows a part of the refrigerated vehicle arrangement from Figure 1 in a perspective side view, Figure 3A-C a part of the refrigerated vehicle arrangement from Figure 1 in a view from below, Figure 4 a part of the refrigerated vehicle arrangement from Figure 1 in a plan view, and Figure 5 a part of the refrigerated vehicle arrangement from Figure 1 in a side view along the Figure 4 drawn plane A - A'.

[0048] In the figures, identical or functionally equivalent components are provided with the same reference numerals.

[0049] In Figure 1an embodiment of a refrigerated vehicle arrangement 2 according to the invention is shown, in which a towed unit in the form of a semi-trailer is used. Instead of a semi-trailer, however, a trailer could also be used. The refrigerated vehicle arrangement 2 has a cooling compartment 4, at the front of which a refrigeration unit 6 is located. The refrigeration unit 6 can be supplied with electrical energy via a battery 8 in order to cool the interior of the cooling compartment 4. The battery 8 can, however, also be arranged in a different position, for example underneath a vehicle frame 10, which is shown only in a simplified manner as two parallel longitudinal members which support the cooling compartment 4. Schematically shown underneath the vehicle frame 10 are a front axle 12, a middle axle 14 and a rear axle 16, by means of which the refrigerated vehicle arrangement 2 can be towed over a roadway 18 by a tractor (not shown).Further components that are not relevant to the actual invention have been omitted for the sake of clarity. This applies, for example, to the coupling to the tractor or the chassis for the front axle 12, the middle axle 14, and the rear axle 16. However, such components are known to a person skilled in the art. Furthermore, . Figure 1 a running wheel 20 can be seen, which can be lowered to the roadway 18 during operation of the refrigerated vehicle arrangement and can charge the battery 8 via a generator.

[0050] In order to better illustrate the other components of the refrigerated vehicle arrangement 2 according to the invention, Figure 2a perspective view is shown in which the cooling compartment 4, the cooling unit 6, and the battery 8 have been removed. It can be seen that several cross members 22 are attached to the vehicle frame 10 between the longitudinal members of the vehicle frame 10. These cross members rest, for example, on the lower chords 24 of the longitudinal members of the vehicle frame 10 and are connected to the longitudinal members of the vehicle frame 10 via corresponding connecting means. In other embodiments, the cooling unit 6 can also be operated without the battery 8.

[0051] With reference to the Figures 3A to 3CThe invention is shown again from a perspective of the underside of the refrigerated vehicle arrangement 2, with the front axle 12 removed. It can be seen that the impeller 20 opens via a half-axle 26, which is designed as a short axle stub, into a pivot lever 28 which can pivot about a pivot axis 30. The pivot axis 30 is rotatably fastened in a holder 32, which is held by the cross members 22. The holder 32 can be formed from two plates 34 arranged parallel to one another in the longitudinal direction, which have two receptacles 36 on their underside which receive the pivot axis 30.The pivot axis 30 is further connected to a working cylinder 38, which enables a rotational movement of the pivot axis 30 via a change in length, so that the running wheel 20 can be transferred from a rest position towards the track 18 or back into the rest position. The working cylinder 38 can, for example, be actuated pneumatically or hydraulically; the use of an electric motor is also conceivable.

[0052] Furthermore, in the Figures 3A to 3Ca generator 40 can be seen, which can be connected to the cross members 22 or to other parts of the vehicle frame 10 via a support 42. On the inside of the running wheel 20 there is a running surface for a first belt 44, which is guided to a pulley 46, which is arranged to rotate directly on the pivot axis 30. Via a second belt 48, the pulley 46 sets the generator 40 in a rotary motion. Due to the different diameters of the running surfaces of the first belt 44 and the second belt 48 on the pulley 46, a transmission can be achieved from the rotation of the running wheel 20 to the rotation of the generator hub 50.

[0053] In order to illustrate the arrangement of the individual elements in the area of ​​the pulley 46 more clearly, reference is made to the Figures 4 and 5 The middle axle 14 and the rear axle 16 are now shown removed. Figure 5a side view in the plane A-A', which in Figure 4 is shown by the dashed line. It can be seen that the generator 40 can be displaced via the support 42 via a swivel joint 52 and a securing device in a slot 54 with regard to the distance to the pivot axis 30, so that, for example, when retrofitting the refrigerated vehicle arrangement 2, a length compensation can be created. This procedure also allows the generator 40 to be replaced, for example, with a more powerful model, which does not necessarily have to have the same external dimensions. The distance between the pivot axis 30 and the semi-axis 26, however, remains unchanged once the length of the pivot lever 28 has been determined. In order to keep the first belt 44 and the second belt 48 in their optimal working ranges, a belt tensioner 56 can be provided, which, however, is not shown in the illustration according to Figure 5 is only shown for the first belt 44.

[0054] By switching on the generator 40 or lowering the impeller 20 using the working cylinder 38, the generation of electrical energy can be controlled according to the needs of the battery 8. It is particularly advantageous to use the generator 40 only when the refrigerated vehicle is coasting, for example, when driving downhill, so that the energy otherwise lost during braking can be recuperated. The generator 40 can also supply the refrigeration unit 6 directly with electrical energy without the battery 8.

[0055] By positioning the impeller 20 close to a slip-free position on the refrigerated vehicle assembly 2 near the central axle 14, no forces are applied to individual wheels of the refrigerated vehicle assembly 2 during the activation of the generator 40, so that recalibration of the assistance systems is unnecessary or can be significantly simplified. The electrical output of the generator 40 can also be subsequently changed by replacing the generator 40, whereby a power output of up to approximately 30 kW can typically be achieved.

[0056] Thus, it is possible to retrofit existing refrigerated vehicles, which may be towed units in the form of a trailer or semi-trailer, with an electric refrigeration unit 6, which is supplied with electrical energy via the battery 8, which in turn can be charged via the generator 40 when the impeller 20 is set in rotation with the roadway 18. Since the generator 40 is connected to the vehicle frame 10, there is no increase in unsprung masses on the front axle 12, the middle axle 14, or the rear axle 16, as occurs with known generator axles. List of reference symbols:

[0057] 2Refrigerated vehicle arrangement 4Refrigeration compartment 6Refrigeration unit 8Battery 10Vehicle frame 12Front axle 14Middle axle 16Rear axle 18Roadway 20Idler wheel 22Cross member 24Lower chords 26Half axle 28Pivot lever 30Pivot axle 32Bracket 34Plates 36Receptacles 38Working cylinder 40Generator 42Support 44First belt 46Pulley 48Second belt 50Generator hub 52Swivel joint 54Elongated hole 56Belt tensioner

Claims

1. Device for operating a generator, which provides a power supply to a towed unit, such as a trailer or a semi-trailer, which has a half-axle (26) which is provided with a running wheel (20) and is connected to the vehicle frame (10) via a pivot lever (28) and a bracket (32) arranged on the bottom of a vehicle frame (10), the pivot lever (28) being pivotable around a pivot axle (30) at the end facing the bracket (32) and being provided with a pulley (46) which is rotatable around the pivot axle (30) and is driven by the running wheel (20) via a first belt (44), the running wheel (20) being arranged in a central region in relation to a longitudinal axis of the vehicle frame (10) and at or near a slip-free position of the towed unit, characterized in that the pulley (46) drives a generator (40) via a second belt (48), which generator is fastened to the vehicle frame (10) and is intended to deliver electrical energy for supply.

2. Device according to claim 1, wherein the generator is connected to a battery system.

3. Device according to claim 1, wherein the generator is directly connected to an electrical consumer.

4. Device according to any of claims 1 to 3, wherein pumps or agitators are supplied in a tank trailer.

5. Device according to any of claims 1 to 4, wherein in a concrete mixer a rotating and tiltable mixing drum is electrically or hydraulically driven via an electric motor.

6. Refrigerated vehicle assembly, in particular a towed unit provided with a refrigeration compartment, such as a trailer or a semi-trailer, comprising the device for operating a generator according to claim 1, wherein the generator (40) is provided for delivering electrical energy for supplying a refrigeration unit (6).

7. Refrigerated vehicle assembly according to claim 6, wherein the generator (40) directly operates the refrigeration unit (6).

8. Refrigerated vehicle assembly according to claim 6, wherein the generator (40) is connected to a battery (8) via which the refrigeration unit (6) is supplied with electrical energy.

9. Refrigerated vehicle assembly according to any of claims 6 to 8, wherein the generator (40) is controlled such that the electrical energy is delivered during an overrun mode of the refrigerated vehicle assembly (2).

10. Refrigerated vehicle assembly according to any of claims 6 to 8, wherein the generator (40) can be shifted relative to the pulley (46) for the length of the second belt (48) to be adjusted.

11. Refrigerated vehicle assembly according to any of claims 6 to 10, wherein the running wheel (20) can be transferred out of or into a rest position without making contact with the roadway.

12. Refrigerated vehicle assembly according to claim 11, wherein the running wheel (20) is transferred out of or into the rest position by means of a control device, and therefore the generator (40) delivers electrical energy depending on a power requirement of the refrigeration unit (6) or a charging requirement of the battery (8).

13. Refrigerated vehicle assembly according to either claim 11 or claim 12, wherein a working cylinder (38) rotates the pivot lever (28) around a pivot axle (30) or a lifting device moves the bracket (32) relative to the vehicle frame (10).

14. Refrigerated vehicle assembly according to any of claims 6 to 13, wherein the pulley (46) has different outer diameters on the running surfaces of the first belt (44) and the second belt (48).

15. Refrigerated vehicle assembly according to any of claims 6 to 14, wherein the running wheel (20) has a smaller diameter compared to the wheels of the towed unit.

16. Refrigerated vehicle assembly according to any of claims 6 to 15, which is attached to the vehicle frame (10), in particular via cross members (22), as part of a retrofit.

17. Refrigerated vehicle assembly according to any of claims 6 to 16, wherein the pivot lever (28) in the form of a rocker is provided with a spring element or wherein a torsion spring is arranged in the region of the pivot axle (30).