EP2282029A1 - Self-propelled machine - Google Patents

Abstract

The machine (F) has a setting and regulating device for setting operation temperature of hydraulic medium to about 60[deg] C. The hydraulic medium cooling region includes a cooler having a fan that is switched ON and OFF, while regulating the speed of fan. The hydraulic medium cooler is structurally separated from the cooling liquid cooling region. The fan is connected with the setting and regulating device. A thermostatic valve controlled by the setting and regulating device is arranged in the hydraulic circuit within a bypass deviating from the cooler.

Description

The invention relates to a self-propelled machine according to the preamble of claim 1.

For such machines, especially road pavers and feeders, a drive concept for functional and working components has prevailed, in which the internal combustion engine acts as a primary drive source, the functional and working components, however, exclusively or almost exclusively by hydraulic means, for example by means of hydrostatic drive units operated. The paver builds on a planum of the paving material at least one ceiling layer with varying working width, levels and compacts this. A feeder holds a sufficiently large stock of the paving material ready and loads the paver so that the paver can work continuously. The feeder and the following paver drive at low installation speed on the surface, eg up to approx. 20 m / min. When transporting to another construction site, a transport speed of up to 20 km / h is common for both machines. The processing of hot bituminous paving material or concrete paving material results in very specific requirements for the hydraulic system and the internal combustion engine, for example due to the material consistency, its tackiness, its processing temperature, drag resistance when installed on the planum or flow resistance during charging, and also from the Depending on the construction site, varying driving resistance coupled with climatic influences, so that at least some hydrostatic drive units have to be designed extremely powerfully, quickly responding and for continuous operation and at the same time individually controlled during operation. This requires strong hydraulic pumps, sometimes long hydraulic paths between the hydraulic pumps and the hydrostatic drive units, and the consideration of high safety and environmental standards. A road paver or feeder with a total weight of around 20 tons contains a considerable volume of hydraulic medium in the hydraulic circuit, for example up to 400 liters or more. For such machines usual hydraulic media (for example specification: HLP 46 according to DIN 51524 part 2) have a behavior of the kinematic viscosity above the temperature at which the viscosity decreases rapidly with increasing temperature, first to about 60 ° C, and about 100 ° C. stays very low. Temperatures of about 100 ° C, however, are critical for seals and hoses in the hydraulic circuit of such self-propelled machines. At about 60 ° C is the viscosity is only half that at 40 ° C, and is only about one tenth of the viscosity at about 0 ° C. Between about 75 ° C to 80 ° C, the viscosity is as low as about one fifth of the viscosity at 40 ° C. The lower the viscosity of the hydraulic medium, the lower the pumping losses and the more sensitive the hydrostatic drive units and pumps will be, and the more efficient they will be. The pumping losses must be compensated by the internal combustion engine, which, for example, runs in normal operation with a rated power of 160 kW at approximately 2000 rpm as the primary drive source. These pumping losses significantly degrade the energy efficiency or energy balance of the self-propelled machine, and offer significant potential for saving primary energy, such as diesel, per year relative to the average operating hours of such a machine.

As is known, for example, from the brochure "SUPER 1603-1" from Joseph Vögele AG, 68146 Mannheim, DE, pages 4, 5, a large Mehrfeldkühlerals cooling device for the engine cooling water of the engine, the hydraulic medium, and in this case, the charge air of eg charged diesel engine, which ensures even at full load and high outside temperatures up to 50 ° C always optimal engine operating temperature and 100% engine performance. The cooling device has at least one fan, which is operated, for example, depending on the engine speed. The cooling device is traditionally designed for the internal combustion engine. Since the hydraulic medium cooling area of the cooling device must be designed so that even under extreme working conditions overheating of the hydraulic medium is reliably avoided, but the cooling control takes place in view of the optimum operating temperature of the internal combustion engine, the hydraulic medium via e.g. more than 95% of the operating time is so cooled that the operating temperature of the hydraulic medium does not exceed approx. 40 ° C. Dictated by the viscosity behavior of the hydraulic medium above the operating temperature, this necessitates a waste of a significant part of the nominal engine power actually applied for processing the paving material, for example to compensate for pumping losses of the hydraulic medium.

In practice, it is also known in such machines to provide the hydraulic medium with its own radiator with a blower driven by a hydraulic motor with an on-off control. Also in this known concept, the operating temperature of the hydraulic medium does not exceed 35 ° C to 40 ° C, because of the importance of the viscosity of the hydraulic medium for the energy balance or energy efficiency of the internal combustion engine For such self-propelled machines for processing bituminous or concrete paving material so far no importance is attached to excessive safety concerns. On the other hand, efforts are increasing to protect the environment even with such machines (global warming, reduction of CO ₂ and NO _x emissions, saving of non-renewable energy sources).

The invention has for its object to provide a self-propelled machine for processing bituminous and / or concrete paving material whose internal combustion engine despite the special requirements due to the difficult processability of the paving materials with improved energy balance and energy efficiency is operable, significantly saves fuel, and the environment spares.

The stated object is achieved with the features of claim 1.

Thanks to the hydraulic medium operating temperature setting and control device, the operating temperature of the hydraulic medium is increased as quickly as possible and then controlled within an operating temperature range in which the additional load of the internal combustion engine is minimized by, for example, pumping losses of the hydraulic medium. Although this means a deliberate departure from the conventional concept of keeping the operating temperature of the hydraulic medium extremely low, for reasons of operational safety, on the other hand, the risk for operational safety does not actually increase at all, since the hydraulic medium operating temperature setting and control device is the one selected Reliably maintains the operating temperature range and maximizes the cooling capacity depending on the hydraulic load condition and the ambient climate when there should be a tendency to exceed the tolerable operating temperature range. For example, this may be the case when at high outside temperatures, low humidity and adverse processing conditions of the paving material and difficult ground and driving conditions, the machine breaks down because of the need to wait for the delivery of fresh paving material, the engine is operated at idle and the Engine cooling capacity is down regulated. The hydraulic medium operating temperature setting and regulating device then regulates eg with maximum efficiency to reliably prevent overheating of the hydraulic medium. Overall, a considerable amount of fuel can thus be saved over the operating time of the machine in normal operation per year. This improvement in the energy efficiency of the internal combustion engine goes hand in hand with optimized operation of the pumps and hydrostatic drive units and rapid response at all times in the hydraulic circuit. Optionally, a loss of power and consumption optimized internal combustion engine can be used without loss in the processing of the installation material.

In an expedient embodiment, the hydraulic medium operating temperature adjusting and regulating device is independent of the engine cooling control system because it is connected to at least one hydraulic medium temperature sensor and / or hydraulic load state information device in the hydraulic circuit and the ambient environment. In this way, for example, at cold ambient temperatures in normal operation running at the rated speed engine and maximum cooling capacity for the cooling liquid, the cooling capacity for the hydraulic medium drastically reduce or completely shut down to achieve optimum viscosity for the hydraulic medium. Conversely, the regulation of the operating temperature sensitively responds to momentary or temporary unfavorable hydraulic load situations or ambient climate situations to optimally set and maintain the operating temperature of the hydraulic medium, although then possibly the engine cooling control system responds differently. The extra expense for the hydraulic medium operating temperature setting and regulating device and its operation required temperature sensors and / or information transmitter is negligible in view of the high potential savings of fuel for the internal combustion engine, without the reliability under the resulting from the processing of the paving material, difficult Requirements for the hydraulic system to endanger. It can save several tons of fuel per year.

In an expedient embodiment, the hydraulic medium operating temperature adjusting and regulating device has a programming and / or setting section for each hydraulic medium operating temperature which is considered optimum so that the hydraulic medium is only cooled to maintain its optimum viscosity, independently how the engine cooling control system works.

In a specific embodiment, preferably in the programming and / or setting section, a selector device for an operating temperature of about 75 ° C to be set for the hydraulic medium to be heated, and an operating temperature range to be maintained of from about 75 ° C to 80 ° C, preferably to about just under 90 ° C, provided. With this operating temperature of the hydraulic medium and this operating temperature range, which is kept in normal operation, the viscosity can be further reduced and optimized, to minimize the additional load on the internal combustion engine from operating the hydraulic system and save even more fuel.

Since, under unfavorable ambient climate conditions, e.g. at low outdoor temperatures and the like, or low processing rate of a built-in material that is very easy to process, e.g. for a thin top layer, possibly not sufficient to cool the hydraulic medium as little as possible to achieve an optimally low viscosity, in a further embodiment in the hydraulic circuit even at least one hydraulic medium heating device is provided. This can be connected to and operated by the hydraulic medium operating temperature setting and regulating device, but can alternatively or independently thereof be operated, for example, with a timer or operator-controlled. The heater not only allows the hydraulic medium to be brought to the optimum operating temperature as quickly as possible, but also to maintain the optimum operating temperature range in normal operation, should the desired elevated operating temperature not be adjustable or stable by minimizing or disabling the cooling power alone.

In an expedient embodiment, the hydraulic medium heater is provided at or in the reservoir of the hydraulic medium, although the heater could be located at any suitable location of the at least one hydraulic circuit. In the reservoir, usually a maximum amount of the hydraulic medium is stored, e.g. about 400 liters, under a relatively moderate return pressure, so that the heater operates efficiently and can be made less pressure resistant.

In an expedient environmentally friendly embodiment, the hydraulic medium heating device is operated with the cooling liquid of the internal combustion engine and / or electrically via a generator driven by the internal combustion engine and / or with waste heat at least of the internal combustion engine. This concept also contributes to the improvement of the energy efficiency of the internal combustion engine, because this heat energy is available anyway, and for example, from the cooling liquid or the waste heat with little extra effort is removable and would otherwise be discharged into the environment anyway.

In an expedient embodiment, the cooling device has a combination cooler (eg a multi-field cooler or a set of separate individual coolers). The combination cooler is associated with a cooling liquid and the hydraulic medium cooling area commonly associated fan, which, preferably, proportional to the speed of the Internal combustion engine can be driven. In order to be able to control the cooling capacity for the hydraulic medium independently of the engine cooling capacity, an adjustable air flow shielding or deflecting device may be provided in the air flow path from the fan to the hydraulic medium cooling area, which, preferably, with the hydraulic medium operating temperature setting and control device is in Verstellverbindung. As soon as the cooling capacity for the coolant for the hydraulic fluid should become too high to set and maintain the desired elevated operating temperature, the cooling capacity is reduced only for the cooling range of the hydraulic medium via the shielding or deflection until the desired operating temperature of the hydraulic medium is reached , In order to maintain the desired operating temperature range of the hydraulic medium, the effect of the shielding or deflection device can then be canceled or regulated accordingly. This does not affect the respectively required cooling capacity, for example for the cooling water of the internal combustion engine, or its intake air, or charge air.

In another embodiment, the hydraulic medium cooling region of the cooling device has a separate blower which can be controlled independently of the blower for the cooling liquid cooling region. Again, the cooling of the hydraulic medium is independent of the engine cooling, for example, the cooling liquid of the internal combustion engine, only with regard to adjust the desired hydraulic medium operating temperature as quickly as possible and then to keep in the desired raised range.

In another embodiment, even a hydraulic medium cooler separated from the cooling liquid cooling region is provided as the hydraulic medium cooling region. This at least one cooler may be associated with a speed-controllable and / or demand-dependent on and off blower, which, preferably, is connected to the hydraulic medium operating temperature setting and control device. Otherwise, the separate arrangement of the hydraulic medium cooler otherwise avoids, for example, unavoidable heating or cooling situations for the hydraulic medium radiator, which could occur in close spatial proximity between the cooling liquid cooling area and the hydraulic medium cooling area. In addition, this concept may be advantageous to the machine to accommodate the tight spaces in the cooling fluid cooling area, and / or to improve the weight distribution in the machine.

In an expedient embodiment, the fan, at least for the hydraulic medium-cooling region, a hydraulic or electric drive motor. The power output and regulation of the drive motor can be adjusted or regulated independently of the speed of the internal combustion engine.

To control the optimum hydraulic medium operating temperature range or for quickly setting the desired hydraulic medium operating temperature independent of the engine cooling, it may be appropriate in the hydraulic circuit in a bypass the hydraulic medium cooling area bypass a thermostatic valve or one of the hydraulic medium operating temperature setting and To arrange-operable control valve, and bypass the hydraulic medium-cooling area completely at least after receiving the normal operation of the machine with cold hydraulic medium over the bypass, eg even when operating a heater for faster heating of the hydraulic medium in the hydraulic circuit or in the hydraulic circuits.

A circulation pump controllable by the hydraulic medium operating temperature adjusting and regulating device is expediently provided in the hydraulic medium cooling region or preferably adjacent thereto, preferably in a shorting section of the hydraulic circuit or hydraulic circuits provided between the reservoir and the hydraulic medium cooling region. By way of example, the delivery rate of the hydraulic medium can be varied via the circulation pump, depending on the cooling demand, in order to intensify or minimize the cooling.

In an expedient embodiment, at least one signal generator for the actual hydraulic medium temperature and / or hydraulic and / or thermal load situations of at least one selected pump and / or a selected hydrostatic drive unit is provided and connected as a control variable generator to the hydraulic medium operating temperature setting and control device. In this case, a pump and / or a hydrostatic drive unit is expediently selected, which is extremely efficient or can be expected in the extreme hydraulic operating situations, so that the hydraulic medium operating temperature setting and control device is quickly informed of a critical condition and can regulate accordingly ,

In another embodiment, a computerized main controller of the machine may be configured as a signal generator for at least the hydraulic and / or thermal load situations for at least one selected pump and / or a selected hydrostatic drive unit. Namely, the main controller may be informed of the loading requirements of the pump and / or the hydrostatic drive unit, for example, because certain operating conditions are set, and so can timely or even preliminarily inform the hydraulic medium operating temperature setting and / or regulating device in order to reliably and preclude overshooting of the operating temperature of the hydraulic medium. Another operating situation by which the main controller can inform the control device is an expected stop of operation, for example at the end of work or a waiting phase for a new supply of paving material, for which the operator has made appropriate preparations at the main control, and for example already the hydrostatic drive units and Internal combustion engine are down regulated. Since the hydraulic medium operating temperature setting and control device is then informed in good time about this future operating state, the hydraulic medium can optionally be cooled again particularly intensively in order to counteract an overshooting of the operating temperature of the hydraulic medium from the beginning of this operating pause.

Basically, according to the invention, a machine for processing bituminous or concrete paving material using an internal combustion engine, especially a diesel engine, operated as a primary drive source for at least one hydraulic system with pumps and hydrostatic drive units so that to improve the energy efficiency of the internal combustion engine during operation or from operating recording of Engine, the hydraulic medium regardless of the load condition of the engine and the engine cooling control depending on the hydraulic load state in the at least one hydraulic circuit and depending on the ambient climate as quickly as possible brought to a raised operating temperature of at least about 60 ° C and then in an operating temperature range above about 60 ° C is controlled in order to waste with the optimal low viscosity of the hydraulic medium as little compensation power of the engine and save as much fuel.

Fig. 1

eine schematische Seitenansicht einer selbstfahrenden Maschine zum Verar- beiten von Einbaumaterial, und zwar eines Straßenfertigers,

Fig. 2

ein schematisches Blockschaltbild eines hydraulischen Antriebskonzeptes der Maschine,

Fig. 3

eine Detailvariante zu Fig. 2,

Fig. 4

ein Schaubild der kinematischen Viskosität eines Hydraulikmediums über der Betriebstemperatur, und

Fig. 5

eine schematische Seitenansicht einer anderen Maschine zum Verarbeiten von Einbaumaterial, nämlich eines Beschickers.

Embodiments of the subject invention will be explained with reference to the drawings. Show it:

Fig. 1

1 is a schematic side view of a self-propelled machine for processing paving material, namely a paver,

Fig. 2

a schematic block diagram of a hydraulic drive concept of the machine,

Fig. 3

a detail variant too Fig. 2 .

Fig. 4

a graph of the kinematic viscosity of a hydraulic medium above the operating temperature, and

Fig. 5

a schematic side view of another machine for processing paving material, namely a feeder.

Fig. 1 shows as an example of a self-propelled machine F a paver for processing bituminous and / or concrete paving material in the production of ceiling layers, for example, from traffic areas or the like.

The machine F has a chassis 32 with a chassis 33 (alternatively a crawler undercarriage) in the embodiment shown, and an internal combustion engine M, e.g. a diesel engine, as a prime mover on. The machine has a variety of functional and working components, which are mainly hydraulically operated and powered by the engine M with drive power. On the chassis 32 is a material bunker 36, from which extends in the chassis 32, a longitudinal conveyor 37 to the rear chassis end, where a transverse distribution device 38 with a height adjustment 47 and a drive 39 are arranged. On the chassis 32, a screed 34 is articulated, the angle of attack adjustable by leveling cylinder 41 and by hydraulic cylinders 42 can be raised. Adjusting cylinders 46, hydraulically operated tamper 44 and hydraulically operated, optional pressure bars 45 are provided in the screed. For the bunker 36 bunker wall adjusting cylinder 41 are provided. The internal combustion engine M is associated with a cooling device K, e.g. with a multi-field cooler and a blower, which, for example, is driven in proportion to the speed of the internal combustion engine M.

The above-mentioned functional and working components of the machine F are operated for processing the paving material by means of hydrostatic drive units or cylinders. For this purpose, at least one hydraulic circuit H ( Fig. 2, 3rd ) and hydraulic pumps and valve assemblies are provided. The various pumps are driven, for example via a pump distributor gearbox from the internal combustion engine. Further, for electric consumers, such as heaters in the longitudinal conveyor 37, for the tamper 44, the pressure bars 45 and unspecified highlighted screed 34 of the screed 34 is driven by the engine M, a generator that provides electrical power available. For the hydraulic circuit (s) (including connecting pipes and connecting hoses) Furthermore, a reservoir for a hydraulic medium (hydraulic oil) is provided, which may have a capacity of several 100 liters. The cooling device K is designed such that the cooling liquid of the internal combustion engine, optionally its intake air or charge air, and also the hydraulic medium are cooled, wherein a cooling control system is provided which primarily the cooling liquid of the internal combustion engine M treated so that the internal combustion engine in normal operation (for example, rated speed about 2000 rpm with a nominal power of about 160 kW) always has optimum operating temperature.

Thus, the hydraulic medium as soon as possible reaches an operating temperature of at least about 60 ° C, preferably between about 75 ° C and 80 ° C or slightly more, and a hydraulic medium operating temperature range of, for example, 75 ° C to 80 ° C in normal operation and independent of ambient climate conditions be complied with is according to Fig. 2 in the machine F, a hydraulic medium operating temperature adjusting and regulating device R is provided which, preferably, independently of the cooling control system S for the cooling liquid of the internal combustion engine M controls the operating temperature of the hydraulic medium.

In Fig. 2 is associated with the internal combustion engine M, for example a diesel engine, a multi-field radiator or a radiator set 1 of a plurality of radiators, in the embodiment shown, a cooling area 1 a for the intake air or charge air, a cooling area 1 b for the cooling liquid of the internal combustion engine M, and a cooling area 1c for the hydraulic medium, and to which a common fan 2 is associated with a drive motor 3, which is controlled by the cooling control system S with respect to the optimum operating temperature of the engine M. 4, the power supply to the drive motor 3 is indicated. The drive motor 3 can be fed, for example, from the hydraulic system, or electrically via the generator G driven by the engine M, or directly or indirectly via the crankshaft of the internal combustion engine M.

To the internal combustion engine M is in Fig. 2 a pump distributor gearbox 5 flanged at the outputs of which a plurality of hydraulic pumps 6 are mounted, which are hydraulically connected via connecting lines or pressure hoses with various hydrostatic drive units 7, 8, 9, 10 for the basis Fig. 1 explained working and functional components of the machine are connected. For example, extends from the hydrostatic drive units 7 to 10, a common return line 11 to a hydraulic medium reservoir 12, usually a large-volume metal container, on the example, valve components 13 may be attached. The reservoir 12 may be connected via a line 14 to the cooling area 1c. The return line 11 may also be connected to the cooling area 1c. Between the reservoir 12 and the valve assembly 13 and the return line 11, a bypass 15 may be provided, in which a thermostatic valve 16 or controllable by the control device R valve 16 may be included for the hydraulic medium flow.

The internal combustion engine M is mounted on a motor console 17, which is mounted on motor bearings 18 on abutments 19 of the chassis 32 of the machine F vibration isolation. The generator G, which is for example driven (not shown) by the pump distributor gear 5, may be mounted on the engine console 17.

In the embodiment shown in FIG Fig. 2 Optionally at least one heating device 20 may be provided for the hydraulic circuit or all hydraulic circuits H of the hydraulic system, for example in the return line 11, or in or at the reservoir 12, or at another suitable location in the machine F. The heating device 20 will be described in US Pat Fig. 2 For example, operated by a controllable by the control device R controller 21 from the generator G electrically. Alternatively or additionally, the heating device 20 could use the cooling water and / or waste heat at least of the internal combustion engine M.

On at least one selected, or on several or all hydrostatic drive units 7 to 10 (or the pump 6) or other suitable locations of the hydraulic circuit H, a temperature sensor 22 for the operating temperature of the hydraulic medium (or a sensor for the hydraulic load condition) is arranged and connected to the control device R. Such a temperature sensor 22 may also be located on or in the reservoir 12, or in or at the cooling area 1c. Furthermore, at least one information transmitter 23, e.g. a temperature and / or humidity sensor, provided and connected to the control device R, which detects the ambient climate. A preferably computerized main control CU of the machine F may also be connected to (or associated with) the control device R, and e.g. in real time or preparatory information i7 e.g. to the hydraulic load state of the selected hydrostatic drive unit 7 provide.

The hydraulic medium operating temperature setting and regulating device R has a programming and / or setting section P at which, for example, the desired operating temperature of the hydraulic medium can be set and monitored, and, if appropriate, a selection device W, at which a hydraulic medium operating temperature of at least about 60 ° C, preferably even about 75 ° C, adjustable, to which the hydraulic medium after commissioning is to be brought as quickly as possible, and an operating temperature range in normal operation of at least about 60 ° C. , preferably about 75 ° C to 80 ° C, or preferably even up to almost 90 ° C, can be adjusted, within which the operating temperature of the hydraulic medium is to be maintained during normal operation of the machine during processing of the paving material, regardless of how the cooling control system S the Cooling at least the cooling liquid for the internal combustion engine M regulates.

In a short circuit 28, for example between the cooling area 1c and the reservoir 12 or the hydraulic circuit H, a circulation pump 29 may be used.

Because of the cooling areas 1 a, 1 b, 1 c commonly associated blower 2 in Fig. 1 is expediently provided in the air flow path from the fan 2 to the cooling area 1c for the hydraulic medium at least one shielding or deflecting device 30, with which the cooling power generated by the blower 2 can be regulated individually for the cooling area 1c, for example via an actuator 31, of the control device R is actuated, or else, not shown, by at least one thermostat or other temperature sensor in the hydraulic circuit. For example, the shielding or deflecting device 30 could include flaps, fins, or other airflow controlling elements.

During operation of the engine F and with the internal combustion engine M, the operating temperature of the hydraulic medium in the hydraulic circuit H is independent of the control intervention of the cooling control system S at least for the cooling liquid of the internal combustion engine M depending on hydraulic load situations in the hydraulic circuit, especially on the hydraulic pumps 6 and / or the hydrostatic drive units. 7 to 10, preferably at a selected pump or drive unit from which, for example, the largest drive power is consumed or in which the strongest variations occur, brought to an optimum in terms of viscosity of the hydraulic medium operating temperature of at least about 60 ° C, and then in a respect Viscosity optimum operating temperature range of above about 60 ° C held to ensure a rapid response of the hydraulic pumps 6 and / or hydrostatic drive units 7 to 10, and to minimize pumping losses in the hydraulic circuit H, the de r Compensate combustion engine M with additional fuel consumption.

Fig. 3 illustrates a detail variant in which the cooling area 1c for the hydraulic medium is structurally separated from the cooling areas 1a and 1b of the cooling device 1. The cooling area 1c is formed by a separate hydraulic medium cooler 24, for example, to the return line 11 and the connecting line 14 to the reservoir 12 is connected, and an independent fan 2a is associated with its own drive motor 3a and a separate drive power supply 4a. The fan 2a may be operated via the control device R, as shown, or is thermostatically controlled only or depending on the measurement result of a temperature sensor in the hydraulic circuit H. The drive motor 3a may be either a hydraulic motor or an electric motor or is (not shown) from the crankshaft driven by the internal combustion engine, for example via a switchable clutch. The radiator 24 may be placed in the cooling device K, or at a suitable position in the engine F.

As a further detail variant is in Fig. 3 indicated that at the reservoir 12 cooling fins 25 may be provided and another blower 26 may be provided with a drive motor 27, which is also controlled for example by the control device R to additionally cool the hydraulic medium in the reservoir 12 as needed. If necessary, ( Fig. 3 ), the heating device 20 is arranged on or in the reservoir 12 in order to achieve as quickly as possible, for example, the desired operating temperature of at least about 60 ° C or more, or to keep the desired operating temperature range of above 60 ° C reliably, the In addition to heat hydraulic medium.

The diagram in Fig. 4 shows for a common hydraulic medium (hydraulic oil of specification HLP 46 according to DIN 51524, Part 2), the behavior of the applied on the vertical axis kinematic viscosity KV above the operating temperature T. The kinematic viscosity is at an operating temperature of about 60 ° C, only half of kinematic viscosity at an operating temperature of about 40 ° C and substantially less than one tenth of the viscosity at about 0 ° C. In an operating temperature range between 75 ° C and about 80 ° C, the viscosity is only about half the viscosity at 60 ° C. This viscosity behavior of the specified hydraulic medium (other common hydraulic media for machines for processing paving material show a similar behavior of the kinematic viscosity over the operating temperature) is in the machine F of FIGS. 1 to 3 , and also the machine F in Fig. 5 used to improve the energy efficiency of the internal combustion engine and fuel by adjusting the relatively high operating temperature of at least about 60 ° C and maintaining an operating temperature range above about 60 ° C to save, in which the hydraulic medium is cooled and / or heated independently of the engine cooling individually.

Fig. 4 illustrates as a built-in material processing machine F a feeder used to load, for example, the paver of Fig. 1 with paving material in front of the road paver drives on the subgrade, intermittently supplied from trucks or continuously via a conveyor with the paving material, and the paver always enough paving material in the bunker 36 fills so that the paver can continuously produce a ceiling layer.

The in Fig. 5 shown feeder has on its chassis 32, the chassis 33, such as a crawler undercarriage, with at least one drive 43, and a very large bunker 36. The feeder is self-propelled and contains, as the primary drive source, the liquid-cooled internal combustion engine M, eg a diesel engine, with the cooling device K at least for the coolant. In the bunker 36, a hydraulically operated transverse conveyor 48 may be arranged, from which an ascending hydraulically operated longitudinal conveyor 49 extends rearwardly upwards, which has a hydraulically adjustable discharge end 52. The conveying device 49 may have a further hydraulic device 50. The feeder as the installation material processing machine F includes, for example, hydrostatic drive units for the traction drives 43, the cross conveyor 48, not shown Bunkerverstellwandzylinder, the device 50 and the discharge end 51, for the internal combustion engine M drives corresponding hydraulic pumps in at least one hydraulic circuit. The cooling device K can according to Fig. 2 or Fig. 3 be adapted to adjust the hydraulic medium in the hydraulic circuit, regardless of the cooling of the cooling liquid of the internal combustion engine M depending on hydraulic load situations and the ambient climate to a hydraulic medium operating temperature of at least about 60 ° C and in a hydraulic medium operating temperature range of about about 60 ° C, preferably between 75 ° C and 80 ° C, in order to optimize the response in the hydraulic circuit, to reduce the viscosity of the hydraulic medium, and to reduce the fuel consumption of the internal combustion engine, which drive the feeder more efficiently and the hydraulic working and functional components more efficiently can operate.

Claims (15)

Self-propelled machine (F) for processing bituminous or concrete paving material, in particular road paver or feeder, with a liquid-cooled internal combustion engine (M) as a primary drive source and at least one pump (6), hydraulic motors or hydrostatic drive units (7 to 10) for functional and working components at least the machine (F), and at least one hydraulic medium reservoir (12) comprising hydraulic circuit (H), a fan-assisted cooling device (K) with cooling areas (1 b, 1 c) for at least the cooling liquid of the internal combustion engine (M) and the hydraulic medium of the Hydraulic circuit (H), and a cooling control system (S) for at least the cooling area (1b) of the cooling device (K), characterized in that for the hydraulic medium cooling area (1c) a hydraulic medium operating temperature setting and - regulating device ( R) is provided, with the hydraulic medium depending on the hydraulic load condition in the hydraulic and ambient temperature to an operating temperature (T) above at least about 60 ° C can be brought and in an operating temperature range at least about above 60 ° C durable. Self-propelled machine according to claim 1, characterized in that the hydraulic medium operating temperature setting and control device (R) from the cooling control system (S) for the cooling liquid of the internal combustion engine (M) independently and at least one hydraulic medium temperature sensor (22) and / or Information transmitter (23, CU) for the hydraulic load state in the hydraulic circuit (H) and the ambient air is connected. Self-propelled machine according to claim 1, characterized in that the hydraulic medium operating temperature adjusting and regulating device (R) has a programming and / or setting section (P) for the hydraulic medium operating temperature. Self-propelled machine according to claim 3, characterized in that , preferably in the programming or / and setting section (P), a selection device (W) for an adjusted for the hydraulic fluid to be heated operating temperature of about 75 ° C and a holding operating temperature range of about 75th ° C to 80 ° C, preferably up to almost 90 ° C, is provided. Self-propelled machine according to claim 1, characterized in that in the hydraulic circuit (H) at least one of the hydraulic medium operating temperature setting and - Regulating device (R) connected hydraulic medium heating device (20) is provided. Self-propelled machine according to claim 5, characterized in that the hydraulic medium heating device (20) is arranged on or in the reservoir (12). Self-propelled machine according to claim 5, characterized in that the hydraulic medium heating device (20) with the cooling liquid of the internal combustion engine (M) and / or electrically via an internal combustion engine (M) driven generator (G) and / or waste heat at least the internal combustion engine (M ) is operable. Self-propelled machine according to at least one of the preceding claims, characterized in that the cooling device (K) a combination cooler (1) with at least the cooling liquid and hydraulic medium cooling areas (1 b, 1 c) or more separate cooler (1, 24) at least as the cooling liquid and hydraulic medium cooling regions (1 b, 1 c) in parallel arrangement and at least one common, preferably proportional to the rotational speed of the internal combustion engine (M) drivable, blower (2, 3, 4), and that in the air flow path from the fan (2, 3, 4) to the hydraulic medium cooling region (1 c) is provided an adjustable Luftstrom-Abschirm- or deflection device (30), which, preferably, with the hydraulic medium operating temperature setting and - Regulating device (R) is in adjusting connection. Self-propelled machine according to claim 8, characterized in that the hydraulic medium-cooling region (1c) has a separate and independently of the blower (2, 3, 4) for the cooling water cooling region (1 b) controllable blower (2a, 3a, 4a). Self-propelled machine according to claim 1, characterized in that as a hydraulic medium cooling region (1c) at least one of the cooling liquid cooling region (1b) structurally separated hydraulic medium cooler (24) with a variable speed and / or on and off blower (2a, 3a, 4a) which, preferably, is connected to the hydraulic medium operating temperature adjusting and regulating device (R). Self-propelled machine according to at least one of the preceding claims, characterized in that the blower (2a, 3a, 4a) for the hydraulic medium cooling region (1c) has a hydraulic or electric drive motor (3a). Self-propelled machine according to at least one of the preceding claims, characterized in that in the hydraulic circuit (H) in a bypass of the hydraulic medium-cooling region (1 c) (15), a thermostatic valve or one of the hydraulic medium operating temperature setting and -Regelvorrichtung (R ) operable valve (16) is arranged. Self-propelled machine according to at least one of the preceding claims, characterized in that a circulation pump (29) which can be controlled by the hydraulic medium operating temperature setting and regulating device (R) is assigned to the hydraulic medium cooling region (1c), preferably in one between the reservoir (1). 12) and the hydraulic medium cooling region (1c) provided short circuit (28) of the hydraulic circuit (H). Self-propelled machine according to at least one of the preceding claims, characterized in that at least one selected pump (6) and / or a selected hydraulic motor or a hydrostatic drive unit (7 to 10) at least one signal generator (22) for the actual hydraulic medium temperature and / or hydraulic and / or associated with thermal load conditions and connected as a control variable generator to the hydraulic medium operating temperature setting and -Regelvorrichtung (R). Self-propelled machine according to claim 2, characterized in that a computerized main control (CU) of the machine (F) as a signal generator for at least the hydraulic and / or thermal load conditions for a selected pump (6) and / or a selected hydraulic motor or a hydrostatic drive unit ( 7 to 10) and signal transmitting with the hydraulic medium operating temperature setting and - Regulating device (R) is connected.

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