EP3705632A1 - Mobile work machine - Google Patents

Abstract

The present invention relates to a mobile work machine, in particular a wheel loader, with a drive motor and with a controller that is designed to read in and / or calculate one or more sensor values relating to the work machine, which is also designed to include the sensor value or values and / or the or to compare the calculated values with limit values or limit value ranges and which is also designed to cause an increase in the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine on the basis of this comparison.

Description

The present invention relates to a mobile work machine, in particular a wheel loader, with a drive motor and with a controller which is designed to read in and / or calculate one or more sensor values relating to the work machine and which is also designed to display the sensor value or values and / or to compare the calculated value or values with limit values or limit value ranges.

In the U.S. 6,052,925 describes a method for determining the front and rear axle load of an earth moving vehicle. From the DE 11 2017 000 049 T5 There is known a work vehicle in which an output control unit of the engine of the work vehicle is configured to set a target rotation speed of an engine using a curve of the output torque of the engine to control an output of the engine. The DE 10 2009 029 559 B4 describes a method for operating an engine of an agricultural combine harvester, with the following steps: detecting a load on the engine, determining whether the load is below a predetermined value, which corresponds to a deactivated unloading system, and dependent from the result of the step of determining, switching the engine to one of a plurality of power curves.

The present invention is based on the object of developing a mobile work machine of the type mentioned at the outset in such a way that temporarily increased power can be provided.

This object is achieved by a work machine with the features of claim 1.

It is then provided that the control of the work machine is designed to cause an increase in the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine on the basis of the comparison mentioned at the beginning. In the context of the present invention, the term “increase” means an increase over the respective nominal values.

This ensures an optimization of the driving and / or the work drive performance and can advantageously protect the weakest component or axle.

If, for example, the operating state "Pushing on material, e.g. silage" is defined or recognized and the sensor values for the mast almost all the way down, wide fork, parallel to the ground, lifting cylinder pressure (ground pressure) small, incline, incline sensor uphill> 5 °, driving speed (drive speed up to 10 km / h) is measured and an axle load distribution is calculated in a predetermined range, the controller determines that an increase in engine power is possible and initiates this.

If, for example, the operating state "stockpiling" is defined or recognized and the sensors determine that the mast is raised, the bucket position is close in, the cylinder pressure is high (ground pressure below the maximum value) and the driving speed is close to zero, and it is calculated that the tractive force distribution and the axle load distribution are in the permissible ranges, the control provides determines that an increase in transmission torque or an increase in tractive force is possible and initiates this.

The operating states, such as Pushing on material, e.g. Silage, a digging process, etc. are preferably recognized automatically based on one or more sensor values. Exemplary are sensor variables or input variables of the working hydraulic pressure, the mast position, the shovel position, the device inclination and / or calculated actual values, such as e.g. to name the axle load distribution and / or the tractive effort. These measured or calculated values are compared with predefined conditions, such as threshold or limit values or condition ranges, and if the operating states are completely identical, i.e. if the measured or calculated values are within permissible ranges, a control response is triggered by the control, e.g. the engine power, torque or pulling force increase.

It is conceivable that the control is designed to compare both sensor values and calculated values with respective limit values or limit value ranges and that the control is also designed to increase the drive motor power and / or the tractive force and / or the gear torque on the basis of both comparisons cause. In this case, at least two conditions would have to be met in order to cause the mentioned reduction or increase.

When "increase" is used in the context of the invention, this means an increase in the drive motor power and / or the tractive force and / or the gear torque.

With regard to the extent of the increase, it can be provided that either the sensor with the minimum or average or maximum value is used as a factor for the increase in power. If, for example, the smallest sensor value is used, it is conceivable that there is an increase of x% compared to the nominal value; for example, the mean value becomes several When sensor values are used, it is conceivable that there is an increase compared to the nominal value in the amount of y%, and if, for example, the largest sensor value is used, it is conceivable that an increase compared to the nominal value of z% occurs.

It is preferably provided that x <y and / or y <z.

It is conceivable that the increase mode, i.e. the operating mode in which an increase can take place is preset by default. However, within this mode it can also be provided that the increase factor compared to the nominal values is 1, i.e. there is in fact no increase.

It is therefore conceivable that if, based on a factory setting, at least one limit value is below / or exceeded, the relevant factor is set to 1, which means that the nominal power and / or nominal tensile force and / or the nominal torque is set or retained.

The parameters whose values can be included are the lifting angle of the work equipment, the tilt angle of the work tool, the working hydraulic pressure of the work equipment and / or the work tool, the traveling speed of the work machine or the inclination of the work machine and / or the mast height or work equipment height.

In a preferred embodiment of the invention it is provided that at least one of the calculated values is the axle load distribution of the work machine.

The controller can be designed to use the sensor value or values and / or calculated values to determine an operating state of the work machine, e.g. Pushing on material, e.g. To identify silage, digging, etc.

It is possible for the controller to be designed so that at least one parameter value is detected and that no increase occurs if the parameter value is not corresponds to a target value or does not lie in a target value range, although the comparison of the sensor values and / or the calculated values with limit values or limit value ranges should result in an increase. This parameter has priority over the comparison mentioned.

It is conceivable that the control is designed to increase the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine also as a function of the determined operating state of the work machine. In other words, the fact whether and, if so, how an increase occurs in this case also depends on the operating state in which the working machine is located.

One of the parameters mentioned is the value of a road driving switch and / or the values of a proximity switch with a grid or one or more suitable sensors that define the off-road operating state. Is the road travel switch, i.e. a switch or the like, active, which signals that the work machine is moving on the road, no increment is made even if the comparison is positive, i.e. when the sensor value (s) and / or the calculated value (s) are in a target range.

The control can be designed to define an operating state from the sensor value (s) and / or calculated values, which includes, for example, pushing on material (e.g. silage) or a digging process, whereby also in temporal segments of the digging process (wood chips stacking, e.g. slightly raised lifting frame) Increase in drive power / tractive power. This means that the detection of a certain operating state does not necessarily mean that an increase will take place as long as the operating state continues. Rather, it is conceivable that an increase only takes place in one or more time segments while the operating state continues.

The control can be designed to cause an increase in the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine only if the calculated value, in particular the calculated axle load distribution, is in a certain range. If this is not the case, there is no increase in this exemplary embodiment, even if other parameter values are in a desired range.

The controller can be designed to change the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine linearly as a function of the calculated value. Any other dependency is of course also encompassed by the invention.

In one embodiment, the calculated value is the axle load distribution, the controller being designed to set the drive motor power to a maximum value when the axle load distribution assumes a first value (e.g. 50:50 (front: rear)) and a smaller one Set value as the maximum value if the axle load distribution assumes a second value deviating from the first value.

It is conceivable that the work machine or its control is designed such that it does not or only allows an increase in the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine, if a previous period the increase in one or more of the parameters mentioned or a previous total duration of the increase in one or more of the parameters mentioned or a previous amount of increase in one or more of the parameters mentioned or a previous number of increases in one or more of the parameters mentioned exceeds a limit value.

It is thus conceivable that the control, in spite of the fulfillment of the criteria for an operating state, the increase in power and / or pulling force provided per se or increasing the transmission torque is reduced or blocked, this reduction or blocking, for example, from a previous period of time in the increase in power and / or tractive force and / or transmission torque and / or from exceeding a summed total duration or exceeding defined number of cycles of increasing the aforementioned Parameter depends.

It is also conceivable that the increase is only carried out in a defined time window and / or only in a time period (i.e. the factor is then set to 1) that is shorter than the time period in which, despite the operating status being recognized and limit values / ranges being observed the comparison is positive.

After automatic operating status detection and comparison with the sensor values / areas, the driver can confirm the increase in one step using a button / switch or a symbol or window on the display, with the power / tractive effort being automatically reduced to the nominal power / tractive effort, in particular with a note, in particular information on the display.

The present invention further relates to a method for operating a work machine according to one of claims 1 to 17, wherein one or more sensor values relating to the work machine are read in and / or calculated so that the sensor value (s) and / or the calculated value (s) with limit values or limit value ranges are compared and that based on this comparison there is an increase in the drive motor power and / or the tractive force of the work machine and / or the transmission torque of the work machine.

In preferred embodiments, the method preferably has one or more of the steps mentioned in claims 2 to 17.

At this point it should be noted that the terms “a” and “an” do not necessarily refer to exactly one of the elements, although this represents a possible embodiment, but can also designate a plurality of the elements. Likewise, the use of the plural also precludes the presence of the element in question in the singular and vice versa the singular also includes several of the elements in question.

Further details and advantages of the present invention are explained in more detail using an exemplary embodiment shown in the drawing.

Figur 1:

ein Ablaufschema eines Verfahrens gemäß der Erfindung,

Figur 2:

ein Schema zur Abhängigkeit der Leistung, Zugkraft und Moment von der Achsverteilung und

Figur 3:

eine Darstellung der Charakteristik der Erhöhung oder Reduzierung von Leistung, Zugkraft und Moment in Abhängigkeit der Achsverteilung.

Show it:

Figure 1:

a flow chart of a method according to the invention,

Figure 2:

a scheme for the dependence of the power, tractive force and moment on the axle distribution and

Figure 3:

a representation of the characteristics of the increase or decrease of power, tractive force and torque depending on the axle distribution.

Figure 1 shows an example of a method for changing the power of the work machine carried out by the control of the work machine according to the invention, such as a wheel loader.

The process begins with a defined start with the detection of conditions such as threshold values etc.

This is followed by the definition of operating states. For example, it is / is defined for which measured or calculated values, e.g. Mast angle, tool position etc. a certain operating condition, such as the stockpiling is available.

The reading in of sensor values follows. The lifting angle, the tilting angle, the working hydraulic pressure, the inclination, etc. are mentioned here as examples. These values are values measured by sensors. This step is in Figure 1 "Reading in sensor values (ACTUAL values)".

This is followed by the calculation of actual values or actual value ranges; the axle load distribution and tractive force distribution are examples.

The step "Conditions 1" is the definition of the situation detection by defining the sensors and their threshold values and the step "Conditions 2" is the definition of the threshold value ranges for the measured parameters.

The comparison of actual values and / or calculated values as conditions 1 and / or conditions 2 and the detection of operating states then takes place. In this context, “calculated values” means the threshold values or limit value ranges in which the actual values must lie in order to meet a condition. These values can be calculated or they can be fixed.

Depending on this comparison, there is one or no increase in the control output values due to the fulfillment of the defined conditions.

For example, an agricultural application (silo pile-up) and the resulting increase in engine power are conceivable; Figure 3 is shown as well as the loading and operation in the heap - stockpiling - with an increase in the maximum output torque from the gearbox (traction).

The process ends with a defined end.

Figure 2 shows the axle distribution load ALV, which can vary between the values 0% and 100%, whereby the load on the front axle VA and on the rear axle HA together always result in 100%.

The reference symbols P represent the engine power of the work machine, ZK its tractive force and M the torque, in particular the gear torque of the work machine.

The exemplary values ALV1, ALV2 and ALV 3 lie in a hatched area in which there is an increase in the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine. There is no such increase outside of this range.

The given, i.e. The hatched area can be stored in the control or can be permanently or repeatedly adapted as required by calculating the axle load distribution.

As an example, ALV2 is a division of the front and rear axle loads, each with 50% of the total axle loads. As stated, the front and rear axle loads always add up to 100%. ALV1 to ALV2 represent the area of an increased rear axle load. ALV2 to ALV3 represent the area of an increased front axle load.

Figure 3 illustrates the change in engine power depending on the calculated axle load distribution.

This change is made in the penultimate step according to Figure 1 .

Like this Figure 3 As can be seen, the characteristic of the increase in performance depends on the axle load distribution ALV and is defined with an axle load distribution of 50/50%, ALV2 with a maximum performance (= certified performance) of P2. ALV1 (VA min.) Is assigned to a nominal power (= nominal power) P1. ALV3 (VA max.) Is assigned to a nominal (= nominal power) P3.

The proportionality between ALV and power between P1, P2 and P2 and P3 (max, VA) behave linearly by way of example, but the invention is not limited to such a linear dependency.

If it is determined within the framework of the company that ALV is calculated as ALV2, i.e. There is a 50:50 axle load distribution, but the engine power is below P2, this is increased to P2 due to the control.

If it is determined from a calculated value of ALV3 that the engine output is higher than P3, the engine output is reduced to this value.

The values in Figure 3 are exemplary.

So ALV1 and ALV3 can differ in terms of performance, e.g. when using different axle sizes. The areas ALV1 and ALV2 or ALV2 and ALV3 can be selected differently. This means that power P1 and / or P3 can be different, i.e. P1 <P3 or P1> P3, i.e. below the nominal power.

Instead of the engine power P, transmission torques M or tensile forces ZK can be applied from the entire drive train, i.e. the change in engine power is only exemplary here.

It is conceivable that it is possible that this power, etc. increasing operation is only switched on in defined operating states with limit values / ranges not exceeded in order to protect the drive components, since unnecessary increases in power / tractive force / torque lead to undesired additional consumption.

In a further embodiment, additional temporary increases are brought about by means of energy stores, for example flywheel stores, batteries, fuel cells, compressed air or hydraulic stores via additional gear drives. However, these variants are complex in terms of integration into the vehicle (additional installation space), control and operation, with the additional effect of energy recovery in relation to wheel loader operations, for example, being manageable.

In the course of the targeted increase in output, the temporary increase in output in the range of a few percent of the total running time means that enlarged components and enlarged peripheral components, e.g. the cooler, are dispensed with.

Additional operating states can be carried out, for example, by including a road switch or querying the functional position of the armrest including steering joystick and / or working hydraulic joysticks using proximity switches and ratchets (toggle switches) on the joystick armrest to assign an off-road operating state. In this context, the EP 3 019 387 B1 referred to, to which reference is made in this regard.

However, any other sensor or switch that defines the operating state of the off-road operation can be integrated. This road travel switch can be any mechanical, electrical switch and / or electronically displayed switch symbol or button that is defined in a display. Additional operating states can also be defined using a door contact switch, for example.

• Nach Ablauf einer hinterlegten Zeitspanne.
• Nach Hubgerüstposition über einem gewissen Wert, nicht im Lademodus
• Nach Erreichen einer hinterlegten Leistungserhöhungszeitspanne, wobei diese die Leistungserhöhung x Zeitspanne ist und in der Steuerung hinterlegt ist.
• Nach Überschreitung einer definierten Maximalgeschwindigkeit, bzw. mehrmalige Überschreitung dieser.
• Nach Ansprechen des Straßenfahrschalters
• Nach Verlassen des definierten Lastbereichs
• Nach Verlassen eines definierten Fahrzeugwinkelbereichs
• Kühlparameter wie Kühlertemperatur wird überschritten, bspw. Motorkühler

In order to prevent damage and misuse, but to ensure the temporary increase in the relevant operating case, operation can be ended in such a way that the nominal output is stopped:

• After a specified period of time has elapsed.
• After mast position above a certain value, not in loading mode
• After reaching a stored power increase time span, this being the power increase x time span and being stored in the control.
• After exceeding a defined maximum speed or exceeding it several times.
• After the road travel switch has responded
• After leaving the defined load range
• After leaving a defined vehicle angle range
• Cooling parameters such as cooler temperature are exceeded, e.g. engine cooler

In one exemplary embodiment, through predictive observation of the operating parameters, the increase in output is only released after the history has been evaluated, with overloading of the drive train being virtually excluded. The power increase is only switched off after the vehicle has been put out of operation, for example "ignition off" or in the event of a sensor error.

Any combination of predictive power or other increase and the additional termination of the power or other increase mode to operate and ensure wear-friendly operation is also possible.

Claims (18)

Mobile work machine, in particular wheel loader, with a drive motor and with a controller that is designed to read in and / or calculate one or more sensor values relating to the work machine, which is also designed to include the sensor value (s) and / or the calculated value (s) To compare limit values or limit value ranges and which is also designed to cause an increase in the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine on the basis of this comparison. Mobile work machine according to claim 1, characterized in that the control is designed to compare both sensor values and calculated values with respective limit values or limit values and that the control is also designed to increase the drive motor power and / or the tractive force based on both comparisons and / or the transmission torque. Mobile work machine according to claim 1 or 2, characterized in that there are several sensors and that the control is designed to use either the minimum sensor value or calculated value or an average value of the sensor values or the calculated values or the maximum sensor value or calculated value Factor to be used for the increase. Mobile work machine according to one of the preceding claims, characterized in that the control is designed so that no increase occurs if the sensor value or the calculated value or, in the case of several sensors, a single sensor value or calculated value outside a limit value range and / or above or is below a limit. Work machine according to one of the preceding claims, characterized in that the sensor value (s) and / or the calculated value (s) include one or more of the values of the lifting angle of the work equipment, the tilt angle of the work tool, the working hydraulic pressure of the work equipment and / or the work tool and / or the mast height or work equipment height, the travel speed of the work machine or the inclination of the work machine. Work machine according to one of the preceding claims, characterized in that the controller is designed that at least one parameter value is detected and that no increase occurs if the parameter value does not correspond to a setpoint value or is not in a setpoint value range, although the comparison of the sensor values and / or the calculated values with limit values or limit value ranges would have to result in an increase. Work machine according to Claim 6, characterized in that there is a road travel switch, in particular a contact or proximity switch and that the parameter value is formed by the position of this switch. Work machine according to one of the preceding claims, characterized in that at least one of the calculated values is the axle load distribution of the work machine. Work machine according to one of the preceding claims, characterized in that the control is designed to determine an operating state of the work machine, such as pushing material (eg silage) or a digging process, from the sensor value or values and / or calculated values. Work machine according to one of the preceding claims, characterized in that the control is designed to define an operating state from the sensor value or values and / or calculated values, which includes, for example, pushing on material (e.g. silage) or a digging process, the control being further designed to bring about the increase in only one or more time segments of the operating state. Work machine according to Claim 10, characterized in that the controller is designed to increase the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine also as a function of the determined operating state of the work machine. Work machine according to one of the preceding claims, characterized in that the control is designed to cause an increase in the drive motor power and / or the tractive force of the work machine and / or the transmission torque of the work machine only when the calculated value, in particular the calculated axle load distribution, is in a certain range. Work machine according to one of the preceding claims, characterized in that the control is designed, although the comparison of the sensor values and / or the calculated values with limit values or limit value ranges should result in an increase, no or only a limited increase in the drive motor power and / or the tractive force and / or to cause the transmission torque if a previous duration of the increase or a previous total duration of the increase or a previous amount of the increase or a previous number of increases exceeds a limit value. Work machine according to one of the preceding claims, characterized in that the control is designed to change the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine linearly depending on the sensor value or values or calculated values. Work machine according to one of the preceding claims, characterized in that the calculated value is the axle load distribution and that the control is designed to set the drive motor power to a maximum value when the axle load distribution assumes a first value and to a value smaller than that Set the maximum value if the axle load distribution assumes a second value that differs from the first value. Work machine according to one of the preceding claims, characterized in that the control is designed such that although the comparison of the sensor values and / or the calculated values with limit values or limit value ranges should result in an increase, the increase is only carried out for a limited period. Work machine according to one of the preceding claims, characterized in that the controller is designed so that if the comparison of the sensor values and / or the calculated values with limit values or limit value ranges should result in an increase, the actuation of a button, switch, etc. by the driver of the Work machine is necessary to trigger the increase and / or that a display is present that is designed to indicate to the driver whether an increase is taking place or not. Method for operating a work machine according to one of Claims 1 to 17, characterized in that one or more sensor values relating to the work machine are read in and / or calculated, that the sensor value (s) and / or the calculated value (s) are compared with limit values or limit value ranges and that this comparison causes an increase in the drive motor power and / or the tractive force of the work machine and / or the gear torque of the work machine.

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