Patent Application
20230302682
The invention relates to a truck-mounted concrete pump with a truck chassis, with a combustion engine for transporting the truck-mounted concrete pump and a hydraulically driven concrete pump superstructure with a distribution boom, a support system and a concrete pump for pumping and distributing fresh concrete.
In today's truck-mounted concrete pumps, a hydraulic pump train, consisting of several hydraulic pumps arranged in series, drives the units of the concrete pump superstructure, for example the concrete pump, the distribution boom, the support system and other units required for operation, is usually driven on the construction site by a diesel engine of the truck chassis.
To reduce the emission of undesirable exhaust gases and climate-damaging carbon dioxide, it is desirable to also drive truck-mounted concrete pumps on the construction site electrically.
In the case of an electrically or hybrid (diesel and electric) driven truck-mounted concrete pump, the problem is that the electrical power provided by an on-board battery and/or a power supply on the construction site is generally not sufficient to drive the truck-mounted concrete pump electrically for the concrete pumping/conveying process sufficiently or for a sufficiently long period of time.
Because purely electric operation of a truck-mounted concrete pump is not possible for this reason, or is at least severely restricted, it would nevertheless be desirable to limit the running time of the diesel engine driving the truck-mounted concrete pump on the construction site as far as possible in order to keep the emission of exhaust gases and noise pollution to a minimum.
A truck-mounted concrete pump with a hybrid drive is described, for example, in patent application DE 10 2018 214 965 A1. According to this patent application, the electric motor and the diesel engine can drive a common hydraulic pump train either alternately or together.
This would make it possible, for example, to set-up and dismantle the concrete pump electrically, i.e., to extend the support systems, unfold the boom, clean the concrete pump, fold in the boom and retract the support system, and to use the diesel engine during pumping operation or connect it to the electric motor.
However, the set-up and dismantling of the truck mounted concrete pump according to this document would be very ineffective, because the electric motor always drives the entire hydraulic pump train, i.e. also the hydraulic pumps for concrete pump operation, even if they are in idle mode.
Moreover, after the actual concreting work, the combustion engine remains in operation for a very long time for cleaning the concrete pump superstructure. The cleaning includes, for example, the suction of a cleaning body through the conveying pipe to remove residual concrete from the conveying pipe and the removal of concrete residues with a water hose or high-pressure cleaner. The cleaning work requires the concrete pump to be operated at least temporarily.
It is therefore the object of the invention to provide a truck-mounted concrete pump that solves the problems mentioned above.
This problem is solved by a truck-mounted concrete pump with the features of claim 1.
The invention proposes a truck-mounted concrete pump having a truck chassis with a combustion drive engine, wherein the combustion drive engine is configured to drive the truck-mounted concrete pump while driving. The truck-mounted concrete pump further comprises a hydraulically driven concrete pump superstructure, including a distribution boom, a support system, and a concrete pump for pumping and distributing fresh concrete. The truck-mounted concrete pump also has hydraulic pumps which are configured to drive the concrete pump superstructure, at least one hydraulic pump configured to drive the concrete pump and at least one further hydraulic pump configured to drive the distribution boom and/or the support system. The truck-mounted concrete pump is characterized in particular in that the combustion drive engine is configured to drive the at least one hydraulic pump, which in turn is configured to drive the concrete pump, and in that an electric motor is configured to drive the at least one hydraulic pump, which is configured to drive the distribution boom and/or the support system.
This means that the hydraulic pump train of a truck-mounted concrete pump according to the state of the art, which is made up of several hydraulic pumps, is divided into two parts with the combustion drive engine driving the hydraulic pump for concrete pump operation. An electric motor which drives the distribution boom or the support system can now be used very effectively, for example to perform the set-up and dismantling of the truck-mounted concrete pump on the construction site with a purely electric drive. The set-up of a truck-mounted concrete pump, i.e. the extension of the support system and the support legs and the unfolding of the distribution boom, takes about half an hour. Dismantling the truck-mounted concrete pump takes about the same amount of time. During these periods, the invention allows the concrete pump superstructure to be effectively powered electrically and there is no need to operate the combustion drive engine during this time. Only for the time of the actual concrete pumping process, which requires a lot of energy, the operation of the combustion drive engine is necessary.
Advantageous refinements and developments of the invention result from the dependent claims. It should be pointed out that the features listed individually in the claims can also be combined with one another in any technologically meaningful manner and thus show further refinements of the invention.
According to an advantageous embodiment, the truck-mounted concrete pump has a hydraulic switching unit configured to connect the distribution boom and the support system alternately to the hydraulic pump configured to drive the distribution boom and/or the support system. This makes it very easy to use the electric motor in conjunction with a hydraulic pump to support the truck-mounted concrete pump and to fold and unfold the distribution boom.
Preferably, the combustion drive engine is additionally configured to drive a hydraulic pump that is configured to drive a pipe switch. The fact that the combustion drive engine also drives the pipe switch which belongs to the concrete pump means that the drive energy of the combustion drive engine can be used effectively for the concrete conveying process.
According to an advantageous embodiment, the combustion drive engine is configured to drive a hydraulic pump which is configured to drive an agitator. Since the combustion drive engine also drives the agitator belonging to the concrete pump, the drive energy of the combustion drive engine can be used effectively for the concrete conveying process.
According to an advantageous embodiment of the invention, the electric motor is configured to drive the hydraulic pump, which is configured to drive the pipe switch. This embodiment allows the operation of the pipe switch by means of the electric motor, for example, in order to clean the pipe switch after the concrete conveying process, so that the combustion drive engine does not have to be switched on for cleaning the pipe switch.
According to an advantageous embodiment, the electric motor is also configured to drive the hydraulic pump, which is configured to drive the agitator, so that the agitator can also be driven purely electrically, for example for the cleaning at the end of concrete distribution.
Preferably, a hydraulic switching device is provided which connects the hydraulic pump configured to drive the distribution boom and/or the support system to the concrete pump. This switching device makes it possible to operate the concrete pump, in particular the differential cylinders of the concrete pump and thus the conveying cylinders of the concrete pump for cleaning operation, without the combustion drive engine having to be switched on for cleaning operation. According to an advantageous embodiment, the electric motor is supplied with power via an electrical switching device. This electrical switching device makes it possible to connect the electric motor to different power sources in a simple manner and to switch between these power sources as required.
In an advantageous embodiment, the electrical switching device is configured to connect an electrical energy storage to the electric motor. This electrical energy storage can, for example, be permanently arranged on the concrete pump superstructure and enables the electric motor to be easily supplied with electrical energy.
In an advantageous embodiment, the electrical switching device is configured to connect a power connection of the construction site to the electric motor. In this way, a simple and permanent power supply can be ensured by means of the switching device.
In an advantageous embodiment, the combustion drive engine is configured to drive an electricity generator. By means of such an electricity generator, for example, the electricity generated by the electricity generator can be used to charge the electrical energy storage unit while driving to and from the construction site.
In an advantageous embodiment, the generator is connected via a coupling to the hydraulic pump which is configured to drive the concrete pump. This coupling makes it possible to decouple the generator, which is connected between the combustion drive engine and the hydraulic pump which is configured to drive the concrete pump, from this hydraulic pump so that the hydraulic pump is not unnecessarily driven while the generator is driven.
In an advantageous embodiment, the generator is configured to drive the electric motor. If, for example, no construction site power supply is available at a construction site and/or the electrical energy storage on the truck-mounted concrete pump is discharged or not available, the truck-mounted concrete pump can be safely be set-up or dismantled if necessary.
Further features, details and advantages of the invention will be apparent from the following description and from the drawings, which show examples of embodiments of the invention. Corresponding objects or elements are provided with the same reference signs in all figures. Showing:
A truck-mounted concrete pump 100 according to the invention is shown in
The concrete pump 111 is typically a two-cylinder piston pump (not shown) with two hydraulically driven differential cylinders and two conveying cylinders that alternately suck fresh concrete from the feed hopper 116 and pump it through the pipe switch 112 into a not shown conveying pipe, which extends along the unfolded distribution boom 107, thus distributing it on the job site.
The hydraulic pump 115, which often also comprises two individual powerful hydraulic pumps arranged in series, drives in particular the differential cylinders of the concrete pump 111, which are not shown here, via a suitable hydraulic control system, which is not shown for reasons of clarity.
A further hydraulic pump 119 supplies either the distribution boom 107 or the support system 108 with hydraulic drive power via a hydraulic switching unit 130. Here, too, the further details of the hydraulic control system are not shown for reasons of clarity. The use of only one hydraulic pump 119 is possible in particular because the distribution boom 107 may not be unfolded until the truck-mounted concrete pump 100 has been properly supported. On the other hand, after completion of the concreting work, the distribution boom 107 must first be completely folded in before the support system 108 can be retracted.
A further hydraulic pump 117 drives the pipe switch 112. For this purpose, the hydraulic pump 117 usually constantly charges a hydraulic pressure accumulator, which is not shown, which provides the energy for rapid switching of the pipe switch 112. For this reason, the hydraulic pump 117 is also referred to as an accumulator charging pump. Another hydraulic pump 118 is used to drive the hydraulic motor of the agitator 113 in the feed hopper 116. Further hydraulic pumps, e.g. for driving a hydraulic oil cooler and other units of the concrete pump superstructure 101, may be present, depending on the equipment of the concrete pump superstructure 101.
The shown size of the hydraulic pumps 115, 117, 118, 119 reflects the power of these pumps. I.e., the power of hydraulic pump 115 is usually greater than the power of hydraulic pump 119. The power of the following hydraulic pumps 117, 118 is usually less than that of the preceding hydraulic pumps.
The combustion drive engine 103 is connected to a gearbox 129 and when the vehicle is in motion, for example, traveling to and from a job site, the wheels of the chassis are driven by the cardan shaft 114. Once the truck-mounted concrete pump 100 arrives at the job site and is positioned, the combustion drive engine 103 can be shut off.
During the set-up of the truck-mounted concrete pump 100, the truck-mounted concrete pump 100 is first supported by extending or folding down the support struts 141 and extending the support system cylinders 109 of the support system 108. For this support operation, the hydraulic pump 119 is driven by the electric motor 124 and the hydraulic oil is supplied to the support 108 via the hydraulic switching unit 130 and a hydraulic control system not shown for clarity. After the truck-mounted concrete pump 100 is properly supported, the distribution boom 107 is unfolded. For this purpose, the hydraulic switching unit 130 is switched over to the operation of the distribution boom 107. In an alternative embodiment not shown, the electric motor 124 drives a shortened hydraulic pump train with separate hydraulic pumps for driving the support system 108 and driving the distribution boom 107. The switching unit 130 would not be required in this alternative embodiment.
Only after the truck-mounted concrete pump 100 has been supported and the distribution boom 107 has been unfolded the combustion drive engine 103 is started for the actual concreting operation and, via the power take-off 123 of the gearbox 129, drives the hydraulic pumps 115, 117 and 118 required for operating the concrete pump 111, the pipe switch 112 and the agitator 113. The distribution boom 107 continues to be driven by means of the electric motor 124 during the concreting operation. After completion of the concreting operation, the combustion drive engine 103 is shut off and the distribution boom 107 is folded in with the aid of the electric motor 124 and then the support system 108 is retracted.
In
The addition of a second power take-off 123 and a transfer case 135 to the drive, as shown in
In further variants, the combustion drive engine 103 could drive the concrete pump 111 and the pipe switch 112 during the pumping operation. The agitator 113 is driven by the electric motor 124, as shown in
In order to switch off the combustion drive engine 103 during pumping breaks, i.e. when waiting for the next truck mixer with fresh concrete, for example, a variant is conceivable in which the boom 107, the support system 108 and the agitator 113 are driven by the electric motor 124 and the hydraulic pumps 118 and 119. The hydraulic pump 117 for driving the pipe switch 112 would then be coupled to the combustion drive engine 103 via the hydraulic pump 115.
Instead of the generator 132 shown here, a generator (e.g., an alternator) associated with the truck 102, for example, or a generator that is not driven by the power take-off 123 can also be used to charge the electrical energy storage 120 while the combustion engine 103 is running.
In
In any of the above embodiments, the electrical energy storage 120 may be, for example, a rechargeable battery. Also, a fuel cell suitable for power supply or also other known types of power supply can be used for supplying the electric motor 124.
The electric motor 124 can be designed as a direct current or alternating current motor. For reasons of clarity, the drawings do not show the DC/AC components and other control components required depending on the electric motor 124 used.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2020 121 350.6 | Aug 2020 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/071995 | 8/6/2021 | WO |
