DE102011017325A1 - Cam shaft adjuster for internal combustion engine of hybrid motor car, has adjustment element connected with storage element for providing temperature-dependent twist moment, where adjustment element is designed as bimetallic element - Google Patents

Abstract

The adjuster has a base phase position setting unit (10) with a temperature-dependent adjustment element (13) for adjusting a base phase position as a function of temperature of an internal combustion engine in an operating mode. The temperature-dependent adjustment element is connected with an energy storage element (11) e.g. bimetal torsion spring, for providing temperature-dependent twist moment. The temperature-dependent adjustment element is designed as a bimetallic element. The temperature-dependent adjustment element is thermally coupled to the engine using a thermal connection unit. An independent claim is also included for a method for operating a cam shaft adjuster.

Description

The invention relates to a camshaft adjusting device according to the preamble of claim 1.

From the DE 10 2007 032 517 A1 A camshaft adjusting device for an internal combustion engine of a motor vehicle is already known, which comprises a Grundphasenlageeinstelleinheit with a force storage element which is provided for at least one engine starting operation to provide a twisting torque, which is provided for adjusting a basic phase position between a crankshaft and a camshaft, and with a temperature-dependent adjusting element , which is provided in at least one operating state to lock in dependence on a temperature, the basic phase position comprises.

The invention is in particular the object of increasing comfort, especially when starting the engine. This object is achieved according to the invention by the features of claim 1. Further embodiments emerge from the subclaims.

The invention relates to a camshaft adjusting device for an internal combustion engine of a motor vehicle, the at least one Grundphasenlageeinstelleinheit with at least one energy storage element, which is provided for at least one engine starting operation to provide a twisting torque, which is provided for adjusting a basic phase position between at least one crankshaft and at least one camshaft , And with at least one temperature-dependent adjusting element, which is provided in at least one operating state to adjust depending on a temperature, the base phase position having.

It is proposed that the temperature-dependent adjusting element for providing a temperature-dependent torque to the power storage element is at least connected. As a result, certain angular positions of the at least one camshaft relative to the at least one crankshaft in dependence on the temperature, in particular when the engine is stopped and / or in case of failure and thus for emergency operation of the internal combustion engine, for. B. in the case of a defect of at least a part of the camshaft adjusting device, in particular in the case of a defect of an adjusting unit of the camshaft adjusting device. Thus, a camshaft adjusting device can be provided with at least two basic phase positions, whereby poor running and / or starting characteristics of the internal combustion engine can be avoided. As a result, the force storage element can be dimensioned smaller and / or designed, in particular a force of the force storage element can be chosen smaller, whereby a force required for adjusting a phase position between the at least one crankshaft and the at least one camshaft force, the adjustment smaller and thus reduced consumption can. The internal combustion engine can be conveniently started at different temperatures, in particular at different engine temperatures, whereby the internal combustion engine is accelerated to a starting rotational speed with little vibration and thus comfort, in particular during an engine starting process, can be improved. Further, engine running performance of the internal combustion engine can be improved at various temperatures, particularly in the event of an error, whereby the comfort can be further increased.

An "engine starting process" is to be understood in particular as a process in which the internal combustion engine is made to start running from an engine standstill and / or when the internal combustion engine is brought to zero starting speed from zero rotational speed and / or the consumer unit is de-energized , The term "for an engine starting process" should be understood in particular before and / or during an engine starting process. A "twisting moment" is to be understood in particular as meaning a force which is intended to rotate a component fixedly connected to the crankshaft or integrally formed with the crankshaft and a component fixedly connected to the camshaft or integrally formed with the camshaft, by a phase angle Adjust between the components and / or adjust. A "basic phase position" is to be understood in particular a phase position which is set in a parked, inactive internal combustion engine and / or in an error case of the adjustment and thus in an emergency powerless and / or independent of a control and / or control unit to a Engine start and / or emergency operation of the internal combustion engine to ensure, in particular a set without an externally controlled, for example, by means of the control and / or regulating unit actuated actuator, phasing. A "phase position" is to be understood in particular as meaning an angle of a relative rotation between the at least one crankshaft and the at least one camshaft, in particular in order to adapt at least valve actuation times to different operating ranges, such as full load, partial load and / or idling, of the internal combustion engine. An "adjustment unit" is to be understood in particular as a unit which is intended to actively adjust a phase position and / or which is actuated by the control and / or regulating unit for adjusting the phase position. Under "Adjustment" in particular an active process, ie a process that is performed with externally, for example by means of the control and / or regulating unit controlled actuators understood. A "control and / or regulating unit" is to be understood in particular as a unit having at least one control unit. A "control unit" is to be understood in particular as meaning a unit having a processor unit and a memory unit as well as an operating program stored in the memory unit. In principle, the control and / or regulating unit can have a plurality of interconnected control units, which are preferably provided to communicate with one another via a bus system, in particular a CAN bus system. By "setting" is meant, in particular, a passive process, ie a process which is carried out without an externally actuated actuator, for example by means of the control and / or regulating unit. By "at least connected" should be understood in particular that the force storage element and the adjusting element are connected to each other and / or at least partially formed integrally with each other. By "in one piece" is to be understood in particular that the force storage element and the adjusting element in each case form each other and / or are formed as one and the same component and thus the component in particular functions of the power storage element and the adjusting element. "Provided" is to be understood in particular specially programmed, designed, equipped and / or arranged.

It is further proposed that the temperature-dependent adjusting element is formed integrally with the force storage element. Thereby, a particularly compact Grundphasenlageeinstelleinheit can be realized.

In an advantageous embodiment, the basic phase position adjustment unit is provided for setting the basic phase position by means of the temperature-dependent torque as a function of the temperature to at least two different temperature-dependent values. Thereby, the engine starting operation and / or the emergency operation can be adapted to at least two temperatures, whereby an adjustment of the basic phase position as a function of at least two operating points of the internal combustion engine can be realized and the comfort can be increased. Preferably, the at least two operating points of the internal combustion engine are designed as a cold start and as a warm start.

It is further proposed that the camshaft adjusting device has at least one thermal connection, which is provided to thermally couple at least the temperature-dependent adjusting element with the internal combustion engine. As a result, a particularly advantageous dependency of the setting of the at least two basic phase positions on an engine temperature can be realized. Furthermore, a particularly simple recognition of the two different operating points can thereby be provided. A "thermal connection" is to be understood in particular as meaning a connection in which thermal energy can be exchanged, wherein a temperature, in particular between the internal combustion engine and the adjusting element, is at least substantially the same. By "at least substantially" should in this context be understood in particular that a deviation of the temperature of the internal combustion engine from the temperature at the setting element and / or the adjusting element, in particular less than 30%, preferably less than 15% and particularly preferably less than 5% is. By "thermally coupled with the combustion engine", the internal combustion engine and the adjusting element are thermally connected to each other by means of an operating means, wherein the operating means is provided in particular for cooling and / or lubrication preferably of the internal combustion engine and advantageously is formed as a fluid and / or as a mist. Preferably, the resource is formed as an oil.

It is also proposed that the camshaft adjusting device has at least one adjusting unit which is provided to actively override the basic phase position setting unit for adjusting a phase position between the at least one crankshaft and the at least one camshaft. As a result, a particularly advantageous camshaft adjusting device can be realized. By "actively override" is to be understood in particular that the adjustment unit for adjusting a phase position can provide a twisting torque in response to a control by the control and / or regulating unit, which is greater than the twisting torque of the Grundphasenlageeinstelleinheit.

In particular, it is advantageous if the Grundphasenlageeinstelleinheit is provided to adjust above a temperature defined by the temperature-dependent setting element, the base phase position in the direction "late". As a result, an advantageous basic phase position for a warm start of the internal combustion engine can be found, as a result of which a comfortable warm start can be achieved.

Further, it is advantageous if the temperature-dependent adjusting element is designed as a bimetallic element. As a result, a particularly advantageous temperature-dependent adjusting element can be found. By a "bimetallic element" is intended in particular an element of at least two, material and / or positively connected materials are understood that have different thermal expansion coefficients compared to each other.

Furthermore, it is advantageous if the energy storage element is designed as a bimetallic spring. Thereby, a one-piece design of the energy storage element with the adjustment can be realized particularly easily.

In a further embodiment according to the invention, the camshaft adjusting device has a control and / or regulating unit which is provided to actively adjust a temperature of the temperature-dependent adjusting element by means of an energization of the temperature-dependent adjusting element. As a result, additionally or alternatively, the twisting moment of the basic phase position setting unit can be actively changed by means of the control and / or regulating unit, whereby the temperature-dependent twisting torque can be adapted to a friction of the camshaft adjusting device, preferably the adjusting unit.

In addition, a method is proposed for operating a camshaft adjusting device of an internal combustion engine of a motor vehicle, in particular a camshaft adjusting device according to the invention, in which at least one Grundphasenlageeinstelleinheit at least for an engine starting operation provides a twisting torque that sets a basic phase between at least one crankshaft and at least one camshaft, wherein a temperature-dependent adjustment provides a temperature-dependent twisting torque, by means of which, as a function of a temperature, a basic phase position between the at least one crankshaft and the at least one camshaft is set to at least two different values. As a result, the basic phase position can be set as a function of a temperature, preferably an engine temperature, whereby a comfortable engine starting process, advantageously a comfortable cold start and a comfortable warm start, can be realized.

Further advantages emerge from the following description of the drawing. In the drawing, an embodiment of the invention is shown. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations.

The 1 schematically shows a camshaft adjusting device for an internal combustion engine of a motor vehicle. The motor vehicle can be designed, for example, as a hybrid motor vehicle, ie as a motor vehicle with at least one internal combustion engine and at least one further drive unit, in which the at least one internal combustion engine and the at least one further drive unit either individually or in combination drive end drive elements, such as drive wheels. Preferably, the at least one further drive unit is designed as an electric motor.

The camshaft adjusting device has a Grundphasenlageeinstelleinheit 10 with a force storage element 11 on, which provides for a motor starting operation and for emergency operation of the internal combustion engine, a twisting torque, which is used for setting a basic phase position between a not shown crankshaft of the internal combustion engine and a camshaft 12 the internal combustion engine is provided. Furthermore, the camshaft adjusting device has a temperature-dependent adjusting element 13 which sets the ground phase position depending on a temperature. The adjustment element 13 Sets the basic phase position depending on a temperature that exists before and during the engine starting operation and in the emergency operation.

To provide a temperature-dependent torque, which is provided for adjusting the basic phase position, the temperature-dependent adjusting element 13 with the energy storage element 11 at least connected. In this embodiment, the temperature-dependent adjustment element 13 integral with the force storage element 11 educated. The adjustment element 13 and the force storage element 11 are formed as one and the same component. To provide a temperature dependence is the adjustment 13 formed as a bimetallic element. The energy storage element 11 is designed to realize a one-piece design as a bimetallic spring. The temperature-dependent adjustment element 13 is to form the energy storage element 11 spirally shaped. The energy storage element 11 and thus the adjustment 13 are formed as a torsion spring. They form a temperature-dependent return spring. Basically, the temperature-dependent adjustment 13 and the force storage element 11 Also be formed separately from each other, wherein the adjusting element 13 and the force storage element 11 are advantageously interconnected in such an embodiment. This would be the power storage element 11 as a conventional torsion spring and the temperature-dependent adjusting element 13 formed as an expansion element with temperature-dependent characteristic.

The one-piece with the adjustment 13 trained force storage element 11 is effective between a crankshaft 16 of the Camshaft adjuster and a camshaft pulley 17 arranged the camshaft adjusting device. The energy storage element 11 and thus the adjustment 13 is with an end 18 firmly on the crankshaft wheel 16 and with another end 19 firmly on the camshaft pulley 17 tethered. The one-piece with the adjustment 13 trained force storage element 11 rotates the camshaft pulley to adjust the basic phase position 17 relative to the crankshaft wheel 16 , The crankshaft wheel 16 is torque-transmitting connected to the crankshaft. It is driven by the crankshaft. The crankshaft wheel 16 is designed as a sprocket. It is driven by a chain from the crankshaft. The camshaft pulley 17 is torque transmitting with the camshaft 12 connected. It is torsion and displacement fixed to the camshaft 12 tethered.

The basic phasing unit 10 represents by means of the temperature-dependent torque, which by the one-piece design of the adjustment 13 with the energy storage element 11 is provided, the base phase position as a function of the temperature on two different temperature-dependent values. It sets a base phase position in the direction of "late" and a basic phase position in the direction of "early" as a function of the prevailing temperature. The basic phasing unit 10 represents above a through the temperature-dependent adjustment 13 defined temperature, the base phase position in the direction of "late" and below by the temperature-dependent adjustment 13 defined temperature, the basic phase position in the direction of "early". It sets the basic phase position when the internal combustion engine is switched off or an active adjustment of a phase position is not possible due to a fault. At this time, the basic phase position adjusting unit 10 depending on the temperature, two values of the basic phase position. If there is a temperature less than a certain temperature, which is due to the adjustment element 13 is defined, the basic phase position setting unit 10 the value "early" of the basic phasing. Is a temperature greater than a certain temperature, which by the adjustment 13 is defined, the basic phase position setting unit 10 the value "late" of the basic phase position, whereby a comfort start, with a warm shut-off internal combustion engine, is realized. This sets a correct phasing between the crankshaft and the camshaft for the comfort start.

In this embodiment, this is integral with the force storage element 11 trained adjustment 13 a 2-stage snap characteristic. The basic phasing unit 10 thus sets discrete, temperature-dependent, different torsional torques, whereby the two different values of the basic phase position, in this embodiment the basic phase position "early" and the basic phase position "late", are set. Basically, this can be integral with the force storage element 11 trained adjustment 13 also have a continuous characteristic, whereby the twisting torque changes continuously with the temperature.

For thermal coupling of the temperature-dependent adjusting element 13 with the internal combustion engine, the camshaft adjusting device has a thermal connection. The thermal connection of the adjusting element 13 with the internal combustion engine is by an arrangement of the adjusting element 13 implemented within an internal combustion engine housing. The adjustment element 13 is arranged in a region in which a temperature is substantially equal to an engine temperature. It is arranged for thermal coupling with the internal combustion engine in a region in which forms a mist of a resource. The equipment is provided for cooling and lubrication of the internal combustion engine. It is designed as a resource oil. In principle, the thermal coupling can also be realized in another manner which appears appropriate to a person skilled in the art, for example by direct contact of the adjusting element 13 with a part of the internal combustion engine and / or by an arrangement in the operating medium. Due to the thermal coupling of the adjusting element 13 with the internal combustion engine provides the basic phasing unit 10 the two different values of the basic phase position as a function of the engine temperature. It sets the basic phase position "Early" in a cold combustion engine and the base phase position "Late" in a warm combustion engine.

For active adjustment of the phase angle between the crankshaft and the camshaft 12 the camshaft adjusting device has an adjusting unit 14 which, for adjusting the phase position, the basic phase position adjustment unit 10 actively overdriven. The adjustment unit 14 provides for the adjustment of the phase position a twisting torque that is greater than that of the Grundphasenlageeinstelleinheit 10 provided twisting moment. It adjusts the phase position as a function of a control unit 15 , The adjustment unit 14 is designed as a hydraulic adjusting unit. In this embodiment, the adjustment is 14 designed as a Flügelzellenversteller. It has an outer rotor and an inner rotor, wherein the inner rotor can be rotated relative to the outer rotor. The outer rotor is fixed to the crankshaft 16 Tied or integral with the crankshaft 16 formed and forms an input of the adjustment 14 , The inner rotor is firmly attached to the camshaft pulley 17 or to the camshaft 12 connected and forms an output of the adjustment 14 , Between the input and the output of the adjustment unit 14 are the force storage element 11 and the adjustment element 13 arranged. Basically, the adjustment 14 also be designed as another, the expert appears reasonable sense adjustment.

For locking a ground phase position, the ground phase position adjustment unit 10 a form-locking unit 20 on. The form-fitting unit 20 locks the ground phase position "Early". It locks the ground phase position, which is below that of the adjusting element 13 set temperature and thus in a cold engine or for a cold start and for emergency operation in a cold engine, whereby a swing around the basic phase position "early" is prevented and the engine can produce maximum torque. The form-fitting unit 20 locks the basic phase position passively, ie independent of the control and regulation unit 15 , and unlocks the basic phase position active, ie depending on the control unit 15 ,

The form-fitting unit 20 is designed as a catch unit. It has a locking pin 21 and one in the camshaft pulley 17 arranged opening 22 on. To lock the basic phase position, the locking pin engages 21 in the opening formed as a bore 22 one. To realize a passive locking of the basic phase position, the form-fitting unit 20 a spring, not shown, axially with respect to the camshaft 12 and thus the camshaft pulley 17 acts. The spring acts on the locking pin 21 and pushes it axially against the camshaft pulley 17 , Represents the ground phasing unit 10 the basic phase position "Early", are the locking pin 21 and the opening 22 axially opposite each other, whereby the locking pin 21 by means of the spring in the opening 22 is pressed and thereby locks the ground phase position. To realize an active unlocking, the form-fitting unit 20 a hydraulic actuator, not shown, which is connected to the control unit 15 connected is. The hydraulic actuator generates as a function of the control unit 15 an unlocking force acting in opposition to the spring. The hydraulic actuator pulls the locking pin 21 for unlocking the base phase layer from the opening 22 , which adjusts the phase position and thus the camshaft 12 can be twisted from the ground phase position.

For controlling and regulating the camshaft adjusting device, the control and regulating unit 15 on. The control unit 15 actively sets a temperature of the temperature-dependent setting element 13 by energizing the adjusting element 13 one. It thereby actively changes the temperature-dependent torque of the basic phase position adjustment unit 10 , The control unit 15 has an energizing function, which is used to actively change the temperature of the adjusting element 13 and thus the twisting torque of the basic phasing unit 10 the adjustment element 13 subjected to an electrical voltage. Basically, however, an active adjustment of the temperature of the adjustment 13 through the control unit 15 be waived, reducing the temperature of the adjustment 13 and thus the twisting moment of the basic phase position adjustment unit 10 only passively adjusted by the engine temperature.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102007032517 A1 [0002]

Claims (10)

Camshaft adjusting device for an internal combustion engine of a motor vehicle, the at least one Grundphasenlageeinstelleinheit ( 10 ) with at least one energy storage element ( 11 ), which is provided, at least for an engine starting process, to provide a twisting torque which is used to set a basic phase position between at least one crankshaft and at least one camshaft ( 12 ) is provided, and with at least one temperature-dependent adjusting element ( 13 ), which in at least one operating state is provided to set the basic phase position as a function of a temperature, characterized in that the temperature-dependent adjusting element ( 13 ) for providing a temperature-dependent torque with the power storage element ( 11 ) is at least linked. Camshaft adjusting device according to claim 1, characterized in that the temperature-dependent adjusting element ( 13 ) in one piece with the force storage element ( 11 ) is trained. Camshaft adjusting device according to claim 1 or 2, characterized in that the Grundphasenlageeinstelleinheit ( 10 ) is provided to set the base phase position by means of the temperature-dependent torque as a function of the temperature to at least two different temperature-dependent values. Camshaft adjusting device according to one of the preceding claims, characterized by at least one thermal connection, which is provided to at least the temperature-dependent adjusting element ( 13 ) to couple thermally with the internal combustion engine. Camshaft adjusting device according to one of the preceding claims, characterized by at least one adjusting unit ( 14 ), which is provided for adjusting a phase angle between the at least one crankshaft and the at least one camshaft (FIG. 12 ) the ground phase position adjustment unit ( 10 ) actively override. Camshaft adjusting device according to one of the preceding claims, characterized in that the basic phase position adjustment unit ( 10 ) is provided above a through the temperature-dependent adjusting element ( 13 ) defined temperature to adjust the base phase position in the direction of "late". Camshaft adjusting device according to one of the preceding claims, characterized in that the temperature-dependent adjusting element ( 13 ) is formed as a bimetallic element. Camshaft adjusting device according to one of the preceding claims, characterized in that the force storage element ( 11 ) is formed as a bimetallic spring. Camshaft adjusting device according to one of the preceding claims, characterized by a control and / or regulating unit ( 15 ), which is provided to a temperature of the temperature-dependent adjusting element ( 13 ) actively. Method for operating a camshaft adjusting device of an internal combustion engine of a motor vehicle, in particular a camshaft adjusting device according to one of the preceding claims, wherein at least one Grundphasenlageeinstelleinheit ( 10 ) provides, at least for an engine starting operation, a twisting torque which has a basic phase position between at least one crankshaft and at least one camshaft ( 12 ), characterized in that a temperature-dependent adjusting element ( 13 ) provides a temperature-dependent twisting torque, by means of which, as a function of a temperature, the basic phase position between the at least one crankshaft and the at least one camshaft (FIG. 12 ) is set to at least two different temperature-dependent values.

Images