ADDITIONAL POWER UNIT AND SYSTEM FOR THE ELECTRIC DRIVE OF A TRUCK-MOUNTED CONCRETE PUMP, AND TRUCK-MOUNTED CONCRETE PUMP

Description

[0001] The invention relates to a system with a truck-mounted concrete pump, wherein the truck-mounted concrete pump has a hydraulically driven concrete pumping system for conveying concrete and a hydraulic pump drive system and an internal combustion engine, wherein the internal combustion engine is designed to drive the hydraulic pump drive system and the hydraulic pump drive system is designed to drive the concrete pumping system, and with an additional unit for electrical drive, wherein the additional unit has an electric motor, wherein the electric motor of the additional unit is designed to drive the additional hydraulic pump drive system.

[0002] In order to reduce the emission of unwanted exhaust gases and climate-damaging carbon dioxide, it is desirable to electrically drive truck-mounted concrete pumps, whose concrete pumping system is usually powered by an internal combustion engine, on the construction site.

[0003] EP 3 591 141 A1 discloses a truck-mounted concrete pump comprising a hydraulically driven concrete pumping system for conveying concrete, a hydraulic pump drive system, and an internal combustion engine. The internal combustion engine is configured to drive the hydraulic pump drive system, and the hydraulic pump drive system is configured to drive the concrete pumping system. The truck-mounted concrete pump has an electric motor, which, among other things, drives the hydraulic pump drive system of the truck-mounted concrete pump itself.

[0004] EP 3 023 212 A1 discloses a truck-mounted concrete pump having two electric motors that can be optionally combined with the drive or the concrete application unit.

[0005] DE 20 2020 101432 U1 discloses a truck-mounted concrete pump, whereby the hydraulic pump train of the truck-mounted concrete pump is driven either by the diesel engine or by the additionally installed electric motor.

[0006] Patent application DE 10 2018 214 965 A1 discloses a truck-mounted concrete pump with a hydraulic drive pump system for driving the concrete pumping system of the truck-mounted concrete pump. The hydraulic drive pump system can also be driven either by an internal combustion engine or an electric motor. For this purpose, the truck-mounted concrete pump must be equipped with an additional electric motor, which would be very costly. Retrofitting would only be possible with very high costs. In addition, the hydraulic drive pump system is designed for drive with an internal combustion engine with an output of over 200 kilowatt hours, while the electric motor, due to the limited electrical power available, can often only drive the hydraulic pump train with an output of less than 100 kilowatt hours. This leads to unnecessary power losses when driving the truck-mounted concrete pump with the electric motor.

[0007] It is therefore an object of the invention to provide a system with which an existing truck-mounted concrete pump with a combustion engine drive can be easily driven electrically.

[0008] It is a further object of the invention to minimize power losses in the electric drive of the truck-mounted concrete pump in order to use the available electrical power as effectively as possible for pumping operation.

[0009] At least one of these objects is achieved by a system having the features of claim 1.

[0010] Advantageous embodiments and further developments of the invention emerge from the dependent claims. It should be noted that the features listed individually in the claims can also be combined with one another in any technologically expedient manner, thus revealing further embodiments of the invention.

[0011] According to the invention, the auxiliary hydraulic pump drive system of the auxiliary unit (200) is designed to hydraulically drive the concrete pumping system of the truck-mounted concrete pump, wherein the auxiliary hydraulic pump drive system of the auxiliary unit is designed to be connected to the concrete pumping system of the truck-mounted concrete pump via hydraulic supply lines. By using an auxiliary unit with an electric motor to drive an auxiliary hydraulic pump drive system to drive the concrete pumping system of the truck-mounted concrete pump, a conventionally designed truck-mounted concrete pump can be very easily driven electrically on a construction site. Only very minor modifications to the truck-mounted concrete pump are necessary to enable electrical operation.The auxiliary hydraulic pump drive system driven by an electric motor can be designed to be driven by the electric motor, which usually has a lower power than the combustion engine, in order to minimize power losses and to optimize the auxiliary unit for the electric drive of the truck-mounted concrete pump.

[0012] Because the truck-mounted concrete pump can be easily connected to an additional unit, for example with hydraulic lines, in order to electrically drive the concrete pumping system of the truck-mounted concrete pump, a truck-mounted concrete pump that was previously driven by a combustion engine, as is usual, can be used on a construction site very easily and without complex modifications for an environmentally friendly electric drive.

[0013] Advantageously, the hydraulic pump drive system of the truck-mounted concrete pump comprises a plurality of hydraulic pumps, and the concrete pumping system of the truck-mounted concrete pump comprises a plurality of hydraulic consumers. The auxiliary hydraulic pump drive system of the auxiliary unit comprises a plurality of hydraulic pumps, and the hydraulic consumers of the concrete pumping system can be connected to the plurality of hydraulic pumps of the auxiliary unit via a plurality of hydraulic supply lines. The hydraulic supply lines allow the hydraulic consumers of the truck-mounted concrete pump to be easily connected to the hydraulic pumps of the auxiliary unit.

[0014] According to an advantageous embodiment, the truck-mounted concrete pump of the system for electrically driving a truck-mounted concrete pump has a hydraulic oil tank, and the auxiliary unit has an auxiliary hydraulic oil tank. The hydraulic oil tank of the truck-mounted concrete pump and the auxiliary hydraulic oil tank are connectable to at least one hydraulic return line. This measure eliminates the need to provide a separate hydraulic return line for each of the hydraulic pumps of the auxiliary unit, significantly reducing the number of hydraulic lines for connecting the truck-mounted concrete pump to the auxiliary unit, making the connection much easier.

[0015] Advantageously, the auxiliary unit has an auxiliary hydraulic oil tank, and the hydraulic oil tank of the truck-mounted concrete pump can be connected to the auxiliary hydraulic oil tank of the auxiliary unit via at least one hydraulic return line. Because the auxiliary unit has its own hydraulic oil tank, which is connected to the hydraulic oil tank of the truck-mounted concrete pump via a hydraulic return line, the auxiliary hydraulic pump drive system always has sufficient hydraulic oil available to drive the concrete pumping system of the truck-mounted concrete pump.

[0016] According to an advantageous embodiment, the hydraulic oil is pumped from the hydraulic oil tank of the truck-mounted concrete pump to the auxiliary hydraulic oil tank of the auxiliary unit. This has the advantage that the hydraulic return line does not have to be designed as a suction line. Only low flow velocities are permissible for a suction line, so a suction line would have to have a very large diameter, which makes it very difficult to connect the hydraulic return line from the auxiliary unit to the truck-mounted concrete pump. If the hydraulic oil is pumped to the auxiliary unit, a pressure line with a high flow velocity and a correspondingly smaller diameter can be used.

[0017] According to a preferred embodiment, the truck-mounted concrete pump of the system according to the invention has at least one hydraulic oil return pump driven by a return drive motor and connected to the hydraulic oil tank of the truck-mounted concrete pump, which is designed to pump hydraulic oil from the hydraulic oil tank of the truck-mounted concrete pump to the additional hydraulic oil tank of the additional unit through the at least one hydraulic return line.

[0018] Preferably, the auxiliary unit has a control unit that regulates the power or speed of the reversing drive motor. This ensures that the oil level in the auxiliary hydraulic tank of the auxiliary unit can be kept as constant as possible.

[0019] According to a further preferred embodiment, the truck-mounted concrete pump of the system according to the invention has a second hydraulic oil return pump driven by the return drive motor, and the auxiliary unit has a hydraulic oil cooler and a second hydraulic return line connected to the hydraulic oil cooler, wherein the second hydraulic oil return pump is designed to pump hydraulic oil from the hydraulic oil tank of the truck-mounted concrete pump through the hydraulic oil cooler into the hydraulic oil tank of the auxiliary unit.

[0020] The reversing drive motor is advantageously designed as an electric motor. This allows the electrical drive power of the auxiliary unit to be used to drive the reversing drive motor.

[0021] Alternatively, the reversing drive motor is advantageously designed as a hydraulic motor. This allows the hydraulic drive power of the auxiliary unit to be used to drive the reversing drive motor.

[0022] The auxiliary unit preferably has a hydraulic oil cooler, and the hydraulic oil is pumped from the hydraulic oil tank of the truck-mounted concrete pump through the hydraulic return line, through the hydraulic oil cooler of the auxiliary unit, and into the auxiliary hydraulic oil tank of the auxiliary unit. This offers the advantage that the hydraulic oil pumped from the hydraulic oil tank of the truck-mounted concrete pump to the auxiliary hydraulic oil tank of the auxiliary unit can be easily cooled in this way, without requiring a separate cooling circuit on the truck-mounted concrete pump or the auxiliary unit. A further advantage is that the hydraulic oil return is split between two hydraulic return lines, the diameters of which can then be selected to be smaller than for a single hydraulic return line. This makes the individual hydraulic return lines easier to handle and connect.

[0023] The auxiliary unit preferably has an electrical supply voltage connection for supplying the electrical power to a control unit of the truck-mounted concrete pump. This has the advantage that the vehicle battery of the truck-mounted concrete pump, which normally provides the electrical power to drive the control unit, is not burdened by the current consumption of the control unit while the combustion engine is not running, and therefore the vehicle battery is not recharged.

[0024] According to an advantageous embodiment of the invention, the truck-mounted concrete pump electrically driven by the auxiliary unit has at least one return drive motor and at least one hydraulic oil return pump, wherein the at least one hydraulic oil return pump is designed to pump hydraulic oil from the hydraulic tank of the truck-mounted concrete pump to the auxiliary hydraulic oil tank of the auxiliary unit. The hydraulic return pump allows the hydraulic oil to be pumped from the truck-mounted concrete pump to the auxiliary unit without the internal combustion engine of the truck-mounted concrete pump having to be running.

[0025] Because the hydraulic oil required to drive the concrete pump system from the auxiliary hydraulic pump drive system is delivered or pumped to the auxiliary unit by a hydraulic oil return pump, a relatively thin pressure hose can be used for the return of the hydraulic oil, compared to a suction hose. Due to the large number and power of the hydraulic consumers to be driven by the auxiliary unit, the hydraulic oil demand of the hydraulic pumps of the auxiliary unit is very high. If, as would actually be usual with the state of the art, the hydraulic oil required by the auxiliary unit were to be sucked in from the hydraulic oil tank of the truck-mounted concrete pump, the required hydraulic return line would have to have a very large diameter due to the limited oil flow rate of a suction hose. A hydraulic return line with a smaller diameter can also be very easily connected to the truck-mounted concrete pump.

[0026] Advantageously, the at least one hydraulic oil return pump is designed to pump hydraulic oil from the hydraulic oil tank of the truck-mounted concrete pump to the additional hydraulic oil tank of the additional unit, so that a sufficient amount of hydraulic oil is always available in the additional hydraulic oil tank of the additional unit for the hydraulic pumps of the additional unit.

[0027] Further features, details, and advantages of the invention will become apparent from the following description and from the drawings, which show exemplary embodiments of the invention. Corresponding objects or elements are provided with the same reference numerals in all figures. They show: Figure 1: System according to the invention for the electrical drive of a truck-mounted concrete pump with an additional unit Figure 2: Hydraulic diagram of the system according to the invention Figure 3: Electrical circuit diagram of the system according to the invention Figure 4: Variant of a hydraulic diagram of the system according to the invention Figure 5: Variant of an electrical circuit diagram of the system according to the invention

[0028] The Figure 1 shows a truck-mounted concrete pump 100, an additional unit 200 and a system with a truck-mounted concrete pump 100 and with an additional unit 200 for electric drive according to the invention.

[0029] In the Figures 1 and 2 All elements typically found in a conventional truck-mounted concrete pump 100 are marked with the reference symbol 1XX. All elements associated with the auxiliary unit 200 are marked with the reference symbol 2XX.

[0030] The truck-mounted concrete pump 100 comprises a hydraulically driven concrete pumping system 110 for conveying concrete and a hydraulic pump drive system 102 and an internal combustion engine 103 ( Fig.2 ), wherein the combustion engine 103 is designed to drive the hydraulic pump drive system 102 and the hydraulic pump drive system 102 is designed to drive the concrete pumping system 110.

[0031] The truck-mounted concrete pump 100 shown here as an example has a concrete pumping system 110 mounted on a truck chassis 130 with a driver's cab. The concrete pumping system 110 includes various hydraulic consumers 111, 112, 113, 114, 115, for example, an agitator 111 for mixing the fresh concrete in the hopper 116, a two-cylinder piston pump 114, for example, consisting of delivery cylinders driven by differential hydraulic cylinders, and a concrete switching valve 112. Instead of a two-cylinder piston pump 114, another pumping technology could also be used, for example, a rotor hose pump. Other hydraulic consumers of the concrete pumping system 110 include, for example, a support 113 and a concrete placing boom 115.The truck-mounted concrete pump 100 could additionally be equipped with a hydraulically driven mixing drum (truck mixer concrete pump) or, for example, be designed as a simple concrete pump mounted on a truck chassis without a mast or outriggers.

[0032] The combustion engine 103 ( Fig. 2 ) of the truck chassis 130 drives the wheels of the truck during driving operation. As soon as the truck-mounted concrete pump 100 has reached the work site, according to the prior art, the internal combustion engine 103 continues to run and is used to drive the concrete pumping system 110. For drive by the internal combustion engine 103, the hydraulic pump drive system 102 of the truck-mounted concrete pump 100 has a plurality of hydraulic pumps 102a1, 102a2, 102b, 102c, 102d ( Fig. 2) which drive the hydraulic consumers 111, 112, 113, 114, 115 of the concrete pumping system 110 via the hydraulic supply lines 109a-d. The hydraulic control lines 109e and 109f serve to control the adjustable hydraulic pumps 102a and 102b by the hydraulic consumers 113 / 115 and 114. The hydraulic pumps 102a1, 102a2, 102b, 102c, 102d ( Fig. 2 ) suck the hydraulic oil for driving the concrete pumping system 110 from a hydraulic oil tank 108 ( Fig. 2 ) of the truck-mounted concrete pump 100.

[0033] The auxiliary unit 200 of the arrangement according to the invention comprises an auxiliary hydraulic pump drive system 202 for hydraulically driving the concrete pumping system 110 of the truck-mounted concrete pump 100 and an electric motor 203 for driving the auxiliary hydraulic pump drive system 202. The electric motor 203 is connected to a power connection, for example, a construction site power distributor 400, via a power distribution unit 205, a power line 226, and a plug 207. The auxiliary unit 200 can, for example, additionally comprise an optional accumulator 206, which, depending on the capacity of the accumulator 206, can drive the electric motor 203 alone for a certain period of time or provide additional power in addition to the construction site power in order to absorb power peaks of the concrete pumping system 110.The accumulator 206 can be charged by the construction site power distributor 400 via the electrical power distribution unit 205, for example, during pumping breaks or phases of low power demand of the concrete pumping system 110. The capacity of the accumulator 206 could also be so large that the construction site power connection 400 can be dispensed with entirely. Alternatively or in addition to the accumulator 206, a fuel cell could be used. The accumulator 206 can, for example, also be arranged outside the auxiliary unit 200. The construction site power distributor 400 could also be supplemented with a fuel cell or an electrical accumulator, for example to supply the entire construction site. In addition to or alternatively to the accumulator 206, the auxiliary unit 200 could have a supercapacitor to bridge short-term power peaks.

[0034] The additional unit 200 could, for example, be mounted on a small van or a trailer or, for example, be arranged in a container and is parked for operation close to the truck-mounted concrete pump 100, for example between the support legs of the support 113.

[0035] The auxiliary hydraulic pump drive system 202 of the auxiliary unit 200 also includes a plurality of hydraulic pumps 202a, 202b, 202c, 202d. The hydraulic consumers 111, 112, 113, 114, 115 of the truck-mounted concrete pump 100 are connected to the plurality of hydraulic pumps 202a, 202b, 202c, 202d of the auxiliary unit 200 via a plurality of hydraulic supply lines 209a-d. Thus, the auxiliary hydraulic pump drive system 202 of the auxiliary unit 200 can electrically drive the hydraulic consumers 111, 112, 113, 114, 115 of the concrete pumping system 110 of the truck-mounted concrete pump 100, and the combustion engine 103 and the hydraulic pump drive system 102 of the truck-mounted concrete pump 100 are not required to drive the concrete pumping system 110. Hydraulic control signals are transmitted via the hydraulic control lines 209e, 209f from the hydraulic consumers 113, 114, 115 to the hydraulic pumps 202a, 202b.When using electronically controlled hydraulic pumps 202a, 202b, these control signals could alternatively also be transmitted electrically.

[0036] The auxiliary unit 200 has an auxiliary hydraulic oil tank 208 and the hydraulic oil tank 108 of the truck-mounted concrete pump and the auxiliary hydraulic oil tank 208 of the auxiliary unit 200 are connected to at least one Figure 1 dotted hydraulic return line 209g are connected to each other to pump hydraulic oil from the hydraulic oil tank 108 of the truck-mounted concrete pump 100 to the additional hydraulic oil tank 208 of the additional unit 200.

[0037] In Figure 2A more detailed hydraulic diagram of the system according to the invention is shown. All elements that must be additionally provided or retrofitted for electric drive by the auxiliary unit 200 in a conventional, i.e., combustion-engine-driven truck-mounted concrete pump 100 are designated here by the reference numerals 3XX, unless they are already present on the truck-mounted concrete pump 100 for other reasons.

[0038] For a better understanding of the invention, the operation of the truck-mounted concrete pump 100 with the combustion engine 103 is first described below.

[0039] The Figure 2The illustrated hydraulic pump drive system 102 of the truck-mounted concrete pump 100, which is driven by the internal combustion engine 103, has, for example, two hydraulic pumps 102a1 and 102a2, which, in internal combustion engine operation, jointly drive the two-cylinder piston pump 114 of the concrete pumping system 110 via the hydraulic supply line 109a. Due to the high power of the internal combustion engine 103, the truck-mounted concrete pump 100 in this example has two hydraulic pumps 102a arranged one behind the other, i.e., mechanically operated in series, in order to achieve the highest possible pumping power and thus fully utilize the power of the internal combustion engine 103. Furthermore, a hydraulic control line 109e leads from the two-cylinder piston pump 114 to the hydraulic pumps 102a1 and 102a2 for controlling the power of the adjustable hydraulic pumps 102a1 and 102a2.

[0040] The hydraulic pump 102b drives the concrete placing boom 115 and the support 113 via the hydraulic supply line 109b. A hydraulic control line 109f also leads back to the hydraulic pump 102b, for example, to adjust the hydraulic pressure of the hydraulic pump 102b to the required supply pressure of the concrete placing boom 115.

[0041] The hydraulic pump 102c, designed as a control pump, drives the concrete changeover valve 112 via an intermediate hydraulic pressure accumulator (not shown) via the hydraulic supply line 109c. The hydraulic pump 102d, designed as a constant-flow pump, drives the agitator 111 in the filling hopper 116 of the truck-mounted concrete pump 100 via the hydraulic supply line 109d.

[0042] All hydraulic pumps 102a-d of the hydraulic pump drive system 102 draw the hydraulic oil directly from the hydraulic oil tank 108 of the truck-mounted concrete pump 100. From the hydraulic consumers 111, 112, 113, 114, 115, the hydraulic oil flows back to the hydraulic oil tank 108 of the truck-mounted concrete pump 100 via the hydraulic return lines 121a-d.

[0043] Depending on the equipment of the truck-mounted concrete pump 100, it could have additional hydraulic pumps. For example, if the truck-mounted concrete pump 100 does not have a concrete placing boom 115 or a support 113, the corresponding hydraulic pump 102b can be omitted. In the case of a truck-mounted concrete pump, for example, an additional hydraulic pump could be provided to drive a mixing drum. The assignment of the hydraulic pumps 102a-d is also variable; this means, in particular, that the constant-flow pumps 102c and 102d can drive additional hydraulic consumers or, for example, can be combined into a single hydraulic pump.

[0044] In the following, the electric drive of the truck-mounted concrete pump 100 by means of the additional unit 200 according to the invention is described.

[0045] The auxiliary hydraulic pump drive system 202 of the auxiliary unit 200, driven by an electric motor 203, has a hydraulic pump 202a, which drives the two-cylinder piston pump 114 of the truck-mounted concrete pump 100 via the hydraulic supply lines 209a and 109a. For this purpose, the hydraulic supply line 209a is connected to the supply line 109a of the two-cylinder piston pump 114, for example, with a hydraulic quick coupling 304a and a T-connector. A hydraulic control line 209e leads from the two-cylinder piston pump 114 to the hydraulic pump 202a.Because the electric motor 203 driving the auxiliary hydraulic pump drive system 202 generally has a lower drive power (e.g., <100 kW) than the combustion engine 103 due to the limited electrical power available, the drive power of the hydraulic pump 202a for driving the two-cylinder piston pump 114 can be dimensioned correspondingly smaller than the combined drive power of the hydraulic pumps 102a1 and 102a2, thus utilizing the available electrical drive power as effectively as possible. This also results in cost savings for the auxiliary unit 200.

[0046] The hydraulic pumps 202b, 202c, and 202d drive the hydraulic consumers 111, 112, 113, and 115, respectively, via the hydraulic supply lines 209b, 209c, and 209d, which establish the connection between the auxiliary unit 200 and the truck-mounted concrete pump 100. In particular, the hydraulic pump 202c of the auxiliary unit 200, which drives the concrete changeover valve 112, can, for example, be dimensioned smaller than the hydraulic pump 102c of the truck-mounted concrete pump 100. Due to the low electric motor drive power of the auxiliary unit 200, the two-cylinder piston pump 114 operates correspondingly slower, allowing more time for the charging process of the hydraulic pressure accumulator for the changeover valve 112. This also increases the efficiency of the auxiliary unit 200 and saves costs.

[0047] The hydraulic pump drive system 102 of the truck-mounted concrete pump 100, driven by the internal combustion engine 103, is typically designed for a variable speed of the internal combustion engine 103 because, when high power is required, for example from the two-cylinder piston pump 114, the engine speed of the internal combustion engine 103 must be increased.

[0048] In contrast, the auxiliary hydraulic pump drive system 202 of the auxiliary unit 200 can advantageously be designed for a constant drive speed of the electric motor 203. This is particularly the case if it is a synchronous electric motor 103, which typically operates at a constant speed and can deliver both high and low power at this constant speed without incurring losses. Knowledge of the constant speed of the electric motor 203 can be used to further optimize the auxiliary hydraulic pump drive system 202.

[0049] The electric motor 203 can drive the hydraulic pumps 202a, 202b, 202c, 202d with a maximum available torque. This available maximum torque can be fully utilized by the hydraulic pump 202a driving the two-cylinder piston pump 114, minus the torque constantly required by the hydraulic pumps 202c and 202d, to drive the concrete pump 114. If the concrete placing boom 115 is moved during pumping operation and the hydraulic pump 202b draws torque from the electric motor 103 for this purpose, the maximum power consumption of the hydraulic pump 202a can be limited accordingly, for example by an electronic or hydraulic control, for the duration of the placing boom movement in order to prevent overloading of the electric motor 103 or an undersupply of the hydraulic drive of the truck-mounted concrete pump 100.

[0050] The hydraulic pumps 202a-d of the auxiliary hydraulic pump drive system 202 suck in the hydraulic oil required to drive the concrete pump system 110 from the auxiliary hydraulic oil tank 208 of the auxiliary unit 200.

[0051] To prevent hydraulic oil from being forced into the hydraulic pumps 102a-d that are not active in this operating mode when the truck-mounted concrete pump 100 is electrically driven by the hydraulic pumps 202a-d of the auxiliary unit 200, a check valve 301a-d is arranged, for example, at the outlet of each hydraulic pump 102a-d. In addition to the hydraulic quick couplings 304a-f, the hydraulic system of the truck-mounted concrete pump 100 for the electric drive has T-type hydraulic connectors for connecting the hydraulic lines 302a-f.

[0052] In this exemplary embodiment, the hydraulic pumps 202a-d of the auxiliary unit 200 are relatively clearly assigned to the hydraulic pumps 102a-d of the truck-mounted concrete pump 100. This does not always have to be the case. For example, with the Figure 2 The illustrated structure of the auxiliary hydraulic pump drive system 202 can also drive a truck-mounted concrete pump 100 that does not have a concrete placing boom 115 and / or a support 113. The corresponding hydraulic pump 202b would then simply not be connected to the concrete pumping system 110. Likewise, individual hydraulic pumps of the auxiliary hydraulic pump drive system 202 could be combined to form one hydraulic pump, for example, with a higher power. This would save one of the hydraulic supply lines 209a-d. On the truck-mounted concrete pump 100, the hydraulic drive current of this combined hydraulic pump can then be divided again. It would also be conceivable to use the Figure 2shown structure of the additional hydraulic pump drive system 202, for example, to electrically drive a truck mixer concrete pump by, for example, assigning one of the hydraulic pumps 202a-d to the mixer drum drive.

[0053] In the Figure 1 All connections on the truck-mounted concrete pump 100 for connecting to the auxiliary unit 200 are located on the right side of the truck-mounted concrete pump 100. These connections can also be located, for example, on the left or on both sides of the truck-mounted concrete pump 100, in order to optionally switch off and connect the auxiliary unit 200 on either side of the truck-mounted concrete pump 100. An arrangement of the connections at other positions on the truck-mounted concrete pump 100 is also conceivable.

[0054] From the Figure 2It is further apparent that the truck-mounted concrete pump 100, for example, has a hydraulic oil return pump 305a for the electric drive by the auxiliary unit 200. This pump is driven by a return drive motor 306 and connected to the hydraulic oil tank 108 of the truck-mounted concrete pump 100, which is connected to the hydraulic tank 108 of the truck-mounted concrete pump 100 via a suction line 309g. In this exemplary embodiment, the return drive motor 306 is designed as an electric motor. The hydraulic oil return pump 305a pumps hydraulic oil from the hydraulic oil tank 108 of the truck-mounted concrete pump 100 to the auxiliary hydraulic oil tank 208 of the auxiliary unit 200 through the at least one hydraulic return line 209g, 209h.

[0055] The return electric motor 306 can, for example, additionally drive a second hydraulic oil return pump 305b, which draws hydraulic oil, for example, from the hydraulic tank 108 via another suction line 309h and pumps it from the hydraulic oil tank 108 of the truck-mounted concrete pump 100 via a hydraulic oil filter 215 and a hydraulic oil cooler 210 to the additional hydraulic oil tank 208 of the auxiliary unit 200. The flow rate of the hydraulic oil return pump 305b should, for example, be matched to the rated output of the hydraulic oil filter 215 so that the amount of oil pumped through the hydraulic oil filter 215 is not too large, thereby destroying the hydraulic oil filter 215. The flow rate of the hydraulic oil return pump 305b is then, for example, approximately half the flow rate of the hydraulic oil return pump 305a.

[0056] Alternatively, using only one hydraulic return line 209g, the hydraulic oil flow on the auxiliary unit 200 could be split into two streams, with one stream leading directly to the auxiliary hydraulic oil tank 208 and another hydraulic stream leading via the hydraulic oil cooler 210 and hydraulic oil filter 215 into the auxiliary hydraulic oil tank 208. Alternatively, the hydraulic flow can be further split to the hydraulic oil cooler 210 and the hydraulic oil filter 215.

[0057] The concrete pumping system 110 of the truck-mounted concrete pump 100 requires compressed air, depending on its equipment, for example, to shut off the concrete delivery line. During operation with the combustion engine 103, this compressed air is generated by a compressor driven by the combustion engine 103, among other things, for supplying the braking system of the chassis 130. Because the combustion engine 103 is not available for compressed air generation during the electric drive by the auxiliary unit 200, the return electric motor 306 can, for example, also drive an air compressor 311, as in Figure 2shown. Alternatively, the compressor 311 could be driven by a separate electric motor arranged on the truck-mounted concrete pump 100. Alternatively, the compressor 311 could also be arranged on the auxiliary unit 200 and additionally driven by the electric motor 203 or a separate electric motor. When the compressor 311 is arranged on the auxiliary unit 200, it is necessary to provide a compressed air hose between the auxiliary unit 200 and the truck-mounted concrete pump 100.

[0058] In the embodiment according to Figure 2The fan of the hydraulic oil cooler 210 is driven by an electric motor 217. Furthermore, the auxiliary unit 200 has a continuously operating oil level sensor 212. Based on the output value of the oil level sensor 212, the control unit 220 regulates the power or the speed of the return electric motor 306 in order to keep the hydraulic oil level of the auxiliary hydraulic oil tank 208, and thus indirectly also the hydraulic oil level of the hydraulic oil tank 108, as constant as possible. Alternatively or additionally, the hydraulic oil tank 108 of the truck-mounted concrete pump 100 could have a corresponding level sensor for regulating the return flow.

[0059] The additional unit 200 further comprises, for example, a discrete fill level sensor 211 which responds to a minimum or maximum fill level of the additional hydraulic oil tank 208 being reached and thus, for example, triggers an emergency stop when one of these fill levels is reached.

[0060] In addition, the auxiliary unit 200 has, for example, a temperature sensor 213 that detects the temperature of the hydraulic oil in the auxiliary hydraulic oil tank 208. Another min / max temperature sensor 214 serves to control the switch-on state of the electric motor 217 of the hydraulic oil cooler 210 in order to cool the hydraulic oil when a maximum temperature is reached.

[0061] In addition, the auxiliary unit 200 can have an oil filter sensor 216, which detects the contamination level of the hydraulic oil filter 215 based on the pressure difference in the hydraulic oil filter 215 and thus triggers a suitable reaction of the control unit 220.

[0062] The control unit 220 of the additional unit 200 is connected to the control unit 120 of the truck-mounted concrete pump 100 via the connector plug 312.

[0063] The Figure 3shows an example of a possible electrical circuit of the additional unit 200, the truck-mounted concrete pump 100 and the system for the electrical drive of a truck-mounted concrete pump 100.

[0064] The circuit of the auxiliary power unit 200 includes a power connection 207, which is connected, for example, to a construction site power distribution board 400, and optionally a battery 206, for example, a high-voltage battery (200V-800V). The power connection 207 and the battery 206 each individually or independently provide the electrical power, in particular for operating the electric motor 203, which drives the auxiliary hydraulic pump drive system 202 of the auxiliary power unit 200.

[0065] An electrical power distribution unit 205 distributes the electrical power provided by the power connection 207 and / or the accumulator 206, in particular, between the electric motor 203 and the high-voltage accumulator 206. For example, the power distribution unit 205 can, on the one hand, directly pass the electrical power from the power connection 207 to drive the electric motor 203. In the event that the electric motor 203 requires no or only a small amount of electrical power, for example, during pumping breaks, the power distribution unit 205 can also redirect electrical power from the power connection 207 to the high-voltage accumulator 206 to charge it.

[0066] The power distribution unit 205 can, for example, be based entirely on direct current technology. This means, for example, that an AC-to-DC converter 224 is arranged between the power connection 207, which typically provides AC voltage, and the power distribution unit 205. The battery 206, which typically provides DC voltage, can be connected directly to the power distribution unit 205.

[0067] The return electric motor 306 arranged on the truck-mounted concrete pump 100 for driving the hydraulic return pumps 305a and 305b is, for example, an AC motor 306 and is operated via an AC converter 223. Likewise, the electric motor 217 for driving the hydraulic oil cooler 210 can be operated via an AC converter 222.

[0068] Furthermore, the auxiliary unit 200 has, for example, a low-voltage accumulator 225, for example, in 24- or 48-volt technology, for the control and regulation tasks. The accumulator 225 can be supplied with electrical energy, for example, by the power distribution unit 205 via the DC-DC converter 221. The accumulator 225 serves in particular to supply the control unit 220 of the auxiliary unit 200 and to supply electrical power to the controller 120 of the truck-mounted concrete pump 100 via the supply voltage connection 310. The fact that the controller 120 of the truck-mounted concrete pump 100 is supplied with electrical voltage by the accumulator 225 during electrical operation of the truck-mounted concrete pump 100 with the auxiliary unit 200 ensures that the vehicle battery of the truck-mounted concrete pump 100 is not overloaded or discharged.The accumulator 225 also prevents the control of the additional unit 200 from being without power if the construction site power supply 400 is interrupted and the accumulator 206 is empty or not present.

[0069] The control unit 220 is connected to a current / power sensor 218, which detects the electrical power drawn from the power connection 207 on the power line 226. This allows, for example, the construction site power connection 400 to be protected from overload and, for example, the electrical power drawn from the construction site power connection 400 to be measured, for example, in order to bill the costs for the drawn electrical power based on this measurement.

[0070] The control unit 220 can also be connected to the accumulators 206 and 225, as well as the converters 219, 221, 222, 223, 224, and the power distribution unit 205, for various control and regulation tasks, via additional control lines, such as a CAN bus system. Furthermore, the control unit 220 is connected to the controller 120 via a control line via the connector 312.

[0071] The electrical control of the auxiliary power unit 200 was illustrated in the exemplary embodiment using an AC electric motor 103 and an AC construction site power connection. Both the electric motor 103 and the construction site power connection could be based on DC technology. The electrical control of the auxiliary power unit 200 would then be constructed differently accordingly.

[0072] The operator of the truck-mounted concrete pump 100 can control and operate the concrete pumping system 110 during electrical operation with the auxiliary power unit 200 as usual via the controller 120, for example, also with a remote control 122. For example, if the concrete placing boom 115 is moved via the remote control 122, a higher output is automatically requested and made available by the hydraulic pump 202b of the auxiliary power unit 200. Accordingly, an increase in the output of the two-cylinder piston pump 114 requested by the operator via the remote control 122 results in the output of the hydraulic pump 202a being automatically increased.

[0073] The two-cylinder piston pump 114 illustrated in this embodiment operates with an open hydraulic circuit, which is particularly evident in the fact that the hydraulic pumps 102a1, 102a2, and 202a only pump the hydraulic oil in one direction. However, a two-cylinder piston pump 114 can also be operated, for example, in a closed hydraulic circuit with a reversing pump that pumps alternately in both directions and a feed pump. To drive a corresponding two-cylinder piston pump 114, the auxiliary unit 200 can, for example, have a corresponding reversing pump and a feed pump as an alternative to the hydraulic pump 202a.

[0074] The auxiliary unit 200 can also be configured to drive the concrete pumping system 110 of the truck-mounted concrete pump 100 in parallel with the internal combustion engine drive of the truck-mounted concrete pump 100. This means, for example, that the auxiliary unit 200 drives the concrete pumping system 110 alone when the concrete pumping system 110 requires little power, for example, when supporting the truck-mounted concrete pump 100 and unfolding the concrete placing boom 115. As soon as the two-cylinder piston pump 114 is put into operation or a high delivery rate of the two-cylinder piston pump 114 is required, the internal combustion engine 103 can be put into operation in addition to the auxiliary unit 200.

[0075] The Figure 4shows a variant of a hydraulic diagram of a system according to the invention, in which only one hydraulic return pump 305 pumps the hydraulic oil back from the hydraulic oil tank 108 of the truck-mounted concrete pump 100 to the hydraulic oil tank 208 of the auxiliary unit 200. The hydraulic return pump 305 is driven by a return drive motor 307, which in this embodiment is designed as a hydraulic motor 307. In this embodiment, the hydraulic pump train 202 of the auxiliary unit contains a further hydraulic pump 202e, which is arranged between the hydraulic pumps 202b and 202c. The hydraulic pump 202e, which is thus also driven by the electric motor 203, is connected via a further hydraulic line 209g to the return hydraulic motor 307 for driving the latter, so that the hydraulic return pump 305 is ultimately driven by the hydraulic pump 202e, or rather, the electric motor 203.

[0076] To cool the hydraulic oil, the drive oil of the hydraulic motor 307 in this embodiment is pumped via the hydraulic oil filter 105 and the hydraulic oil cooler 107 of the truck-mounted concrete pump 100 into the hydraulic oil tank 108. Although this cools only a smaller amount of oil than when driven by the internal combustion engine 103, the required cooling capacity is correspondingly reduced due to the lower drive power of the auxiliary unit 200. When operated with the internal combustion engine 103, an additional hydraulic pump (not shown) of the hydraulic pump train 102 pumps the hydraulic oil from the tank 108 via the oil filter 105 and the hydraulic oil cooler 107 back into the tank 108. This hydraulic pump (not shown) is separated from the drive of the hydraulic motor 307 for operation by the auxiliary unit 200 by a check valve (not shown). The Figure 2The necessary additional hydraulic oil cooler 210 and hydraulic oil filter 215 of the auxiliary unit 200 are thus eliminated. The control unit 220 of the auxiliary unit 200 continuously determines at least the hydraulic oil fill level of the auxiliary hydraulic oil tank 208 and, in this exemplary embodiment, regulates the power of the hydraulic motor 307 via the power adjustment of the hydraulic pump 202e, which supplies the hydraulic motor 307 with hydraulic oil. Alternatively, a controllable hydraulic pump 307 controlled by the controller 120 could also be used for this purpose. An electrically driven cooling fan of the hydraulic oil cooler 107 of the truck-mounted concrete pump 100 can, for example, be supplied with electrical drive energy from the auxiliary unit 200. In the case of a hydraulic drive of the cooling fan, it can, for example, be supplied with hydraulic energy from the auxiliary unit 200, like the return hydraulic motor 307.

[0077] In order to ensure the compressed air supply of the truck-mounted concrete pump 100, in the embodiment according to Figure 4 An air compressor 227 driven by an electric motor 228 is provided, which delivers compressed air via a connecting line to the truck-mounted concrete pump 100. Alternatively, the air compressor 227 could also be arranged on the hydraulic pump train 202 and driven by the electric motor 203. Alternatively, a hydraulic motor could drive the compressor.

[0078] The Figure 5 shows an alternative electrical circuit diagram for the power supply of the additional unit 200 of the system according to the invention for the electrical drive of a truck-mounted concrete pump 100.

[0079] In contrast to the circuit diagram according to the Figure 3 For reasons of clarity, the low-voltage power supply is not shown here. Figure 5The cooling circuit 231 required for cooling the components is shown with dashed lines. The high-voltage power supply (AC and DC) is in the Figure 5 shown with solid lines and control lines with dotted lines.

[0080] The main difference in the electrical control of Figure 5 compared to Figure 3consists in the provision of two power connections 207a and 207b. These can be identical power connections (e.g., 440V / 63A three-phase current each) or power connections with different power ratings. If the construction site power supply allows the connection of both power connections 207a and 207b, the electric motor 203 can be driven with a correspondingly higher electrical power, so that the truck-mounted concrete pump 100 can also deliver the concrete with greater performance. If only one construction site power connection is available, the auxiliary unit 200 is supplied with a correspondingly lower electrical power.

[0081] A power line leads from each of the power connections 207a and 207b to the two converters 224a and 224b, respectively, to convert the alternating voltages from the construction site power connections into a high-voltage direct voltage, for example, 655 volts DC. Each converter 224a and 224b consists, for example, of one or more commercially available high-voltage chargers connected in parallel. In the exemplary embodiment shown here, both power connections 207a and 207b are identical, resulting in identical converters 224a and 224b. In the event that one of the power connections 207a or 207b is designed, for example, for a lower electrical AC voltage, current or even for a DC voltage connection (e.g. a CCS DC voltage supply, as is known for charging electric vehicles), the converters 224a and 224b will be different or may, under certain circumstances, be completely omitted.

[0082] The converters 224a and 224b supply high-voltage direct current to both the accumulator 206 and the converter 219, which supplies the electric motor 203 with alternating current. The control unit 220, connected to an input and output unit 227, controls the current input and output of the converters 224a, 224b, the high-voltage accumulator 206, and the converter 219 via the control lines shown in dotted lines, adapted to the respective operating situation. If, for example, the electric motor 203 requires little or no electrical power due to a pumping interruption of the truck-mounted concrete pump 100, the control unit 220 can cause the accumulator 206 to use excess power from the power connections 207a and 207b for charging.If a high electrical drive power is required for the electric motor 203 during pump operation, this power can be provided in parallel by the accumulator 206 and the converters 224a and 224b. The control unit 220 can, for example, be PLC-based and connected to the individual modules via CAN interfaces.

[0083] A 232 earth fault monitor continuously checks the system for earth faults and other fault currents and can trigger an emergency shutdown if necessary.

[0084] The auxiliary unit 200 also has an emergency stop circuit (not shown). This means that upon actuation of an emergency stop switch or button connected to the control unit 220, all or part of the functions of the auxiliary unit 200 are deactivated. Furthermore, the control unit 220 of the auxiliary unit reports the emergency stop actuation on the auxiliary unit 200 to the control unit 120 of the truck-mounted concrete pump 100, so that an emergency stop is also automatically triggered on the truck-mounted concrete pump. Conversely, actuation of an emergency stop button on the truck-mounted concrete pump 100 also triggers an emergency stop on the auxiliary unit 200.

[0085] The cooling circuit 231 shown as an example for liquid cooling of the components includes a pump 229 driven by a low-voltage electric motor and a cooler 230. The coolant is first pumped to accumulator 206, which is the most demanding in terms of cooling. From accumulator 206, the coolant is routed parallel to converters 224a and 224b and to converter 219, before finally passing through electric motor 203 to cooler 230. Depending on the cooling power requirements and the temperature sensitivity of the individual components, other configurations of the cooling circuit 231 are conceivable.

[0086] It should be noted that two exemplary versions of the hydraulics ( Figures 2 and 4 ) and the electrics ( Figures 3 and 5). Technologically expedient adaptations and combinations of the exemplary embodiments shown here, familiar to those skilled in the art, could be made to both the hydraulic and electric drive systems without deviating from the invention. The scope of the invention is defined by the respective subject matter of the claims. List of reference symbols

[0087] 100 Truck-mounted concrete pump 102 Hydraulic pump drive system I (truck-mounted concrete pump) 102a-d Hydraulic pumps 103 Combustion engine 105 Oil filter truck-mounted concrete pump 107 Hydraulic oil cooler truck-mounted concrete pump 108 Hydraulic oil tank truck-mounted concrete pump 109a-d Hydraulic supply line 109e,f Hydraulic control line 110 Concrete pump system 111 Agitator 112 Concrete changeover valve 113 Support 114 Two-cylinder piston pump 115 Concrete placing boom 116 Filling hopper 120 Truck-mounted concrete pump control system 130 Truck chassis 121a-d Hydraulic return lines truck-mounted concrete pump 122 Remote control truck-mounted concrete pump 200 Additional power unit 202 Additional hydraulic pump drive system 202a-e Hydraulic pumps 203Electric motor 205Power distribution unit 206High-voltage battery 207Power connection 208Auxiliary hydraulic oil tank 209a-dHydraulic supply line 209e,fHydraulic control line 209g,hHydraulic return line 210Hydraulic oil cooler 211Min / Max oil level sensor 212Oil level sensor 213Temperature sensor 214Min / Max temperature sensor 215Hydraulic oil filter 216Oil filter sensor 217Electric motor oil cooler 218Current / power sensor 220Auxiliary unit control unit 221DC converter 222AC converter 223AC converter 224AC / DC converter 225Accumulator (24V / 48V) 226Power line 227Input / output unit 228Electric motor compressor drive 229Cooling pump 230Cooler 231Cooling circuit 232Ground fault monitor 301a-eCheck valves 304a - dHydraulic quick coupling supply 304 e, fHydraulic quick coupling control 304 g,hHydraulic quick coupling return 305aHydraulic return pump tank 305bHydraulic return pump oil cooler 305Hydraulic return pump (alternative) 306Return drive motor, electric 307Return drive motor, hydraulic 308Return electric motor connection 309g,hSuction line return pump 310Supply voltage connection 311Air compressor 312Control connection 400Construction site power distributor,

Claims

1. System with a truck-mounted concrete pump (100), wherein the truck-mounted concrete pump (100) has a hydraulically driven concrete pumping system (110) for conveying concrete and a hydraulic pump drive system (102) and an internal combustion engine (103), wherein the internal combustion engine (103) is designed to drive the hydraulic pump drive system (102) and the hydraulic pump drive system (102) is designed to drive the concrete pumping system (110), and having an auxiliary unit (200) for electrical drive, wherein the auxiliary unit (200) has an electric motor (203), wherein the electric motor (203) of the auxiliary unit (200) is designed to drive an auxiliary hydraulic pump drive system (202) of the auxiliary unit (200) characterized in that the auxiliary hydraulic pump drive system (202) of the auxiliary unit (200) is designed to hydraulically drive the concrete pump system (110) of the truck-mounted concrete pump (100), wherein the auxiliary hydraulic pump drive system (202) of the auxiliary unit (200) is designed to be connected to the concrete pump system (110) of the truck-mounted concrete pump (100) by means of hydraulic supply lines (209a-d).

2. System according to claim 1, characterized in that the concrete pump system (110) of the truck-mounted concrete pump (100) has a plurality of hydraulic consumers (111, 112, 113, 114, 115, 307) and in that the hydraulic pump drive system (102) of the truck-mounted concrete pump (100) has a plurality of hydraulic pumps (102a1, 102a2, 102b, 102c, 102d) for driving the plurality of hydraulic consumers (111, 112, 113, 114, 115) and in that the auxiliary hydraulic pump drive system (202) of the auxiliary unit (200) comprises a plurality of hydraulic pumps (202a, 202b, 202c, 202d, 202e) and wherein the hydraulic consumers (111, 112, 113, 114, 115, 307) of the truck-mounted concrete pump (100) can be connected to the plurality of hydraulic pumps (202a, 202b, 202c, 202d, 202e) of the auxiliary unit (200) by means of a plurality of hydraulic supply lines (209a-d, 209g).

3. System according to claim 1 or 2, characterized in that the truck-mounted concrete pump (100) has a hydraulic oil tank (108) and in that the auxiliary unit (200) has an auxiliary hydraulic oil tank (208), wherein the hydraulic oil tank (108) of the truck-mounted concrete pump (100) and the auxiliary hydraulic oil tank (208) of the auxiliary unit (200) can be connected to one another by at least one hydraulic backflow line (209g, 209h).

4. System according to claim 3, characterized in that the hydraulic oil is supplied from the hydraulic oil tank (108) of the truck-mounted concrete pump (100) to the auxiliary hydraulic oil tank (208) of the auxiliary unit (200) via the at least one hydraulic backflow line (209g, 209h).

5. System according to claim 3 or 4, characterized in that the truck-mounted concrete pump (100) comprises at least one hydraulic oil backflow pump (305, 305a, 305b) connected to the hydraulic oil tank (108) of the truck-mounted concrete pump (100) and at least one backflow drive motor (306, 307), wherein the backflow drive motor (306, 307) is designed to drive the at least one hydraulic oil backflow pump (305, 305a, 305b), wherein the at least one hydraulic oil backflow pump (305a, 305b) is designed to convey hydraulic oil from the hydraulic oil tank (108) of the truck-mounted concrete pump (100) to the auxiliary hydraulic oil tank (208) of the auxiliary unit (200) through the at least one hydraulic backflow line (209g, 209h).

6. System according to claim 5, characterized in that the auxiliary unit (200) has a control unit (220), wherein the control unit (220) regulates the power of the at least one backflow drive motor (306, 307) of the truck-mounted concrete pump (100).

7. System according to claim 5 or 6, characterized in that the truck-mounted concrete pump (100) has a second hydraulic oil backflow pump (305b) driven by the backflow drive motor (306, 307), and in that the auxiliary unit (200) has a hydraulic oil cooler (210) and a second hydraulic backflow line (209h) connected to the hydraulic oil cooler (210), wherein the second hydraulic oil backflow pump (305b) is designed to feed hydraulic oil from the hydraulic oil tank (108) of the truck-mounted concrete pump (100) through the hydraulic oil cooler (210) into the hydraulic oil tank (208) of the auxiliary unit (200).

8. System according to any one of claims 5 to 7, characterized in that the backflow drive motor (306, 307) is designed as an electric motor (306).

9. System according to any one of claims 5 to 7, characterized in that the backflow drive motor (306, 307) is designed as a hydraulic motor (306).

10. System according to any one of claims 3 to 9, characterized in that the auxiliary unit (200) has a hydraulic oil cooler (210) and that hydraulic oil from the hydraulic tank (108) of the truck-mounted concrete pump (100) is supplied through the at least one hydraulic backflow line (209h) through the hydraulic oil cooler (210) of the auxiliary unit (200) into the auxiliary hydraulic oil tank (208) of the auxiliary unit (200).

11. System according to any one of the preceding claims, wherein the auxiliary unit (200) has an electrical supply voltage connection (310) for supplying electrical power to a control unit (120) of the truck-mounted concrete pump (100).