DE102016211145B4 - Actuated pulley clutch with centrifugal and inertial actuators - Google Patents

Abstract

Pulley clutch (1) for the required, detachable torque-transmitting connection of a generator-connected pulley (2) to an output shaft (6) that can be driven by an internal combustion engine, with at least one movable start/boost pawl (7) connected to the pulley (2), which is used to apply torque is prepared for a flange (4) that can be connected to the output shaft (6) in a first direction of rotation in an engine starting mode, with at least one movable generator pawl (8) connected to the belt pulley (2), which is used to apply torque from the flange (4) to the Pulley (2) is prepared in a second direction of rotation opposite to the first direction of rotation in normal operation and/or engine starting operation, further comprising a centrifugal actuation means (9) and an inertia actuation means (12), characterized in that the centrifugal actuation means ( 9) is so operatively related to the generator latch (8) that in an f when the centrifugal force actuating means (9) is not actuated by centrifugal force, the generator pawl (8) is freed from torque-transmitting engagement with the flange (4), and the inertia actuating means (12) is in an operative relationship with the start/boost pawl (7), that the start/boost pawl (7) can be brought between a torque-transmitting position with the flange (4) during engine starting operation and during normal operation and a torque-free position during stationary air-conditioning operation due to inertia.

Description

The invention relates to a pulley clutch for the required, detachable torque-transmitting connection of a generator-connected pulley to an output shaft that can be driven by an internal combustion engine, such as a crankshaft, with at least one movable start/boost pawl connected to the pulley, which is used to apply torque to a flange that can be connected to the output shaft in a first direction of rotation in an engine starting mode, with at least one movable generator pawl connected to the pulley, which is prepared for applying torque from the flange to the pulley in a second direction of rotation opposite to the first direction of rotation in a normal mode and/or an engine starting mode, further having a centrifugal actuator and an inertial actuator. Such belt pulley clutches are used in order to be able to drive an air conditioning compressor/a refrigerant compressor by a generator unit/a starter generator when the combustion engine is not running. In addition, the invention relates to a belt drive with this belt pulley clutch and a method for operating the belt drive.

Torque transmission devices are already known from the prior art, such as from WO 2014/079427 A1 . A torque transmission device with at least one freewheel is disclosed there, the freewheel being switchable in order to enable torque transmission in opposite relative directions of rotation. What has been found there to be special is that the freewheel and a freewheel lockup clutch can be switched by a common switching device.

From the still patent application DE 10 2014 216 082 A1 the applicant is also aware of a switchable freewheel for a motor vehicle with a first ring which is arranged concentrically with a second ring. There it is disclosed that, depending on the switching position of the freewheel, torque can be positively transmitted via at least one pawl pivotably connected to one of the two rings to the other of the two rings, with the pawl being pivotable between an engaged position engaging in the profile and a zero position is, in which at least as far as there is no form fit between the pawl and the profile that no torque can be transmitted between the rings. What was particularly found there is that the pawl is connected to a fulcrum on one ring and its center of gravity is arranged relative to the fulcrum that the pawl pivots about the fulcrum induced by centrifugal force as a function of a rotational speed of one ring.

From another patent application by the applicant, namely the DE 10 2014 217 599 A1 a freewheel and a method for switching a freewheel is known. The freewheel is designed as a ratchet freewheel for blocking or interrupting a torque transmission, in particular for selectively switching on an electric machine on a drive train of a motor vehicle. It has a first ring, designed in particular as an inner ring, for introducing and/or discharging a torque. It also has a second ring, which is arranged essentially coaxially to the first ring and is designed as an outer ring, which is provided for dissipating and/or introducing the torque. There are also several first locking elements that can be moved, in particular pivoted, between a locking position and a freewheeling position, the first locking element in the locking position locking the first ring with the second ring for torque transmission when the first ring overtakes the second ring in a first circumferential direction and in the freewheel position allows a relative rotation of the first ring to the second ring to interrupt the torque transmission. Furthermore, there are a plurality of second locking elements that can be moved, in particular pivoted, between a locking position and a free-wheeling position, the second locking element in the locking position when the first ring overtakes the second ring in a second circumferential direction opposite to the first circumferential direction Torque transmission locks and allows in the freewheeling position relative rotation of the first ring to the second ring to interrupt the torque transmission. A first shift cage is used to move the first locking elements between the locked position and the freewheel position. A shifting element that acts directly or indirectly on the second locking elements for moving the second locking elements between the locked position and the free-wheeling position is also disclosed. The switching element is coupled to the first ring or the second ring via a guide element guided in a link guide so that it can move relatively in the circumferential direction and in the axial direction and, during a relative movement to the first ring or second ring coupled via the link guide, between a relative blocking position in which the second Locking elements are positioned in the locked position, and a relative freewheel position in which the second locking elements are positioned in the freewheeling position, axially displaceable.

The moves in this complex of topics DE 10 2011 015 280 A1 , which is a crankshaft pulley for transmitting torque disclosed between a crankshaft and a belt drive, with a coupling device that can be passively actuated using inertia and under the action of centrifugal force.

• So ist in der besagten WO 2014 079 427 A1 ein Klinkenfreilauf in einer Riemenscheibenkupplung beschrieben. Der Freilauf hat dabei Klemmelemente für beide Drehrichtungen, wobei die Klemmelemente mittels eines gemeinsamen Käfigs abwechseln deaktiviert bzw. aktiviert werden können.

The well-known principles rely on different approaches:

• So is in said WO 2014 079 427 A1 describes a ratchet freewheel in a pulley clutch. The freewheel has clamping elements for both directions of rotation, with the clamping elements being able to be activated and deactivated alternately by means of a common cage.

In said DE 10 2014 201 858 A1 a ratchet freewheel is described, which is actuated by means of a lifting magnet.

while the DE 10 2014 216 082 A1 describes a ratchet freewheel whose pawls are engaged under centrifugal force, goes the DE 10 2014 217 599 A1 here one step further. It describes a pawl freewheel in which the pawls of a first direction of action are engaged under centrifugal force, while the pawls of a second direction of action are actuated by means of a shift gate. The actuation is caused by a relative rotation of the inner ring to the outer ring. The pawls acting in the second effective direction are only deactivated as long as the direction of the relative rotation is opposite to the normal operating direction of rotation. This then corresponds to turning backwards in stationary air conditioning mode.

This is also a laborious way DE 10 2011 015 280 A1 , which describes a pulley with a coupling device, in which the coupling device is actuated by means of inertia and centrifugal force.

The one in the WO 2014/079427 A1 Unfortunately, the device disclosed has the disadvantage that a moment/torque can be transmitted either in a first direction of action, in no direction of action, or in a second direction of action. This arrangement is particularly unfavorable in the case of frequent traction/overrun switchovers, since the switchover device must always be actuated during a traction/overrun switchover. However, frequent switching events make the system susceptible to disturbances.

Also the one in the DE 10 2014 201 858 A1 The pulley clutch described basically meets the requirements in terms of functionality, but unfortunately has the disadvantage that it requires an extra / separate actuator to operate the pawls. However, the aim of the present invention is, among other things, to obtain the same functionality but without using an additional actuator. A simplification of the belt pulley clutch should therefore be achieved. Here the older registrations of the DE 10 2014 216 082 A1 or DE 10 2014 217 599 A1 continue, but it has been found to be disadvantageous there that the pulley clutches there only open on one side if no centrifugal force acts. In the DE 10 2014 217 599 A1 Although the second direction is also opened by rotating the belt pulley backwards, the mechanism is closed again by rotating it forwards. There is still potential for optimization here.

Even the DE 10 2011 015 280 A1 still has disadvantages, namely, among other things, that the carrier / mass ring of a toothed element only meshes when the belt pulley accelerates. However, as soon as the acceleration approaches zero, the toothed element is no longer meshed. It is also not possible to transfer a boost torque with this arrangement.

Other torque transmission devices or pulleys with decoupling elements such as centrifugal clutches or freewheels are from the publications DE 10 2012 208 318 A1 , DE 10 2014 214 306 A1 and WO 2014/ 187 458 A1 famous.

It is the object of the present invention to eliminate the disadvantages of the prior art and in particular to provide a particularly durable, precise and cost-effective belt pulley clutch. There is also a desire for a belt pulley clutch to be permanently closed during normal operation of a drive and to transmit torque in both effective directions. There is also the desire that the belt pulley clutch can be opened from a standstill and that it no longer transmits or can transmit torque in any effective direction. This means that when the belt pulley clutch is open, it should be possible for the belt pulley to be rotated in both directions of rotation relative to its hub.

However, the belt pulley clutch should not be actuated by an additional actuator, but rather by a switching signal that is generated by the generator unit in the belt drive.

The object is achieved with a generic pulley clutch according to the invention in that the centrifugal actuation means is in operative relationship with the generator pawl that in a centrifugal force-inactivated position of the centrifugal actuation means, the generator pawl from torque-transmitting engagement is released from the flange and the inertial actuating means is in an operative relationship with the start/boost pawl in such a way that the start/boost pawl, due to mass inertia, moves between a position in which torque is transmitted with the flange during engine starting operation (flange preferably only in the first direction of rotation (via start/boost pawl) rotatably coupled with pulley) and during normal operation (flange preferably in the first direction of rotation (via start/boost pawl) and in the second direction of rotation (via generator pawl) with pulley rotatably coupled to the first direction of rotation) and one torque transmission-free position (belt pulley clutch completely disengaged / open; flange neither in the first direction of rotation nor in the second direction of rotation connected to the pulley in rotation / coupled in rotation) can be brought with stationary air conditioning operation. A centrifugal actuation means (also referred to as a centrifugal weight arrangement) is operatively related to the generator pawl in such a way that when it is in the non-actuated position by centrifugal force, the generator pawl is brought out of torque-transmitting use with the flange and/or an inertial actuation means (also referred to as an inertial mass arrangement) is so operatively related with the start/boost pawl states that in the inertia-actuated position the start/boost pawl is specifically engaged or disengaged from the flange.

In addition to a centrifugal mechanism designed in this way (consisting of a start/boost pawl, generator pawl and centrifugal actuation means), which is used as a ratchet freewheel with pawls (start/boost pawl and generator pawl) for both torque directions and a common inner and outer ring where the pawls are actuated to transmit torque in a first torque direction, a second mechanism (inertial actuating means) is now introduced which actuates the pawls to transmit torque in a second torque direction. The second mechanism uses strong acceleration of the belt pulley as a switching signal. An inertial mass is attached to the pulley via a dead center spring, also known as an over-center spring. The torsion in the inertial mass relative to the pulley is used to actuate the pawls. Due to the (over) dead center spring, there are two stable switching states in the end positions. One switching state includes an activated boost latch, whereas the other includes a deactivated boost latch. In the two operating states, i.e. normal operation and stationary air conditioning, the two actuating mechanisms block each other so that unintentional shifting cannot occur.

Advantageous exemplary embodiments are also claimed in the dependent claims and explained in more detail below.

It is advantageous if the inertia actuating means can be preloaded into two stable positions by an over-center spring. Unintentional switching or enabling can then be prevented.

For efficient shift generation, the inertial actuation means can also have a mass ring with an outer contour that is matched to a centrifugal weight of the centrifugal actuation means, which also makes it possible to control difficult operating states.

An advantageous embodiment is also characterized in that the switching positions of the mass ring and the centrifugal weight and the outer contour of the mass ring and the outer contour of the centrifugal weight are matched to one another in such a way that the mass ring then holds the centrifugal weight in the centrifugally inactivated position when the start/boost pawl is brought into its torque-transmission-free position or the outer contour of the mass ring and the outer contour of the centrifugal weight are matched to one another in such a way that in the mass inertia-actuated position of the mass ring, the mass ring acts on the centrifugal weight by means of a positive and/or non-positive fit such that this the centrifugal force is held in the unactuated position. The ground ring can also be referred to as a ground ring.

If the centrifugal weight is/is forced into the non-actuated position by a return spring, it is possible to leave one operating state and reach the other operating state.

It is also advantageous if the flange configured as a curved flange preferably has discrete latching contours or recesses for receiving the start/boost pawl and/or the generator pawl in a torque-transmitting manner.

In order to increase reliability, it is advantageous if a large number of start/boost latches and/or generator latches are used.

It is advantageous if the pawls, in particular both types of pawls, are distributed alternately over the circumference.

It is advantageous for meshing if the pawls are arranged in opposite directions.

The pawls can also have a common inner and outer ring.

In particular, it is generally expedient if the inertia actuating means is operatively connected to the centrifugal actuating means by means of a coupling, with the coupling being designed in such a way that, in at least one position of the inertial actuating means relative to the centrifugal actuating means, it enables the actuation/adjustment of the Start / boost latch and / or the actuation / adjustment of the generator latch prevents. This coupling means that a switching inhibition is implemented in a structurally particularly simple manner.

In this context, it is also useful if the coupling is designed in such a way that it allows the start/boost latch and/or the generator latch to be opened/disengaged by the respective actuating means (inertial actuating means/centrifugal force actuating means) in normal operation, ie at a speed greater than or equal to an internal combustion engine idle speed, prevented. An engaged position of the belt pulley clutch is then kept particularly stable.

Does the inertial actuation means have a (first) actuation element/blocking element that acts on the start/boost pawl (which is preferably connected directly to the mass ring) and/or the centrifugal actuation means has a (second) actuation element that acts on the generator pawl to adjust / Blocking element (which is preferably connected directly to the centrifugal weight), the operative connection between the pawls and the actuating means is implemented particularly directly.

The invention also relates to a belt drive (also referred to as a belt drive system/belt drive kit) for a motor vehicle, with a generator unit/an electric motor/a starter generator, a pulley clutch according to at least one of the versions described above, a preferably the generator unit with the pulley of the pulley clutch at least in one Assembled state of the belt drive rotatably coupling belt and at least one tensioning unit prepared for tensioning the belt, such as a tensioning roller. Furthermore, it is advantageous if the belt drive has a refrigerant compressor/air conditioning compressor, which in turn is coupled in terms of movement by the belt when the belt drive is in the installed state. At least one pump/several pumps is/are also expediently provided in the belt drive. There are even preferably several tensioning units in the belt drive. Thus, the belt drive can be switched over between the desired operating states in a particularly clever manner by controlling the generator unit via the belt pulley clutch.

The invention also relates to a method for operating a belt drive, which is preferably designed according to one of the belt drive designs described above, with a belt pulley clutch according to one of the designs described above, a refrigerant compressor (preferably a refrigerant compressor of a vehicle air conditioning system), an electric generator unit, as well as a refrigerant compressor and generator unit with an output shaft of an internal combustion engine and belts that are coupled to one another, with the generator unit exerting a brief, high initial acceleration on the belt of the belt drive after the internal combustion engine has been switched off, thereby completely opening the belt pulley clutch (ie the start/boost pawl and the generator pawl out of positive contact with flange and pulley) and then the generator unit by a second acceleration, which is smaller than the first acceleration, by d he output shaft decoupled belt drives up to an operating speed of the refrigerant compressor. This implements a particularly clever, automatable switching process for the belt pulley clutch.

In addition to this method or as an alternative method, it is also possible to use a method for operating a belt drive, which is preferably designed according to one of the belt drive designs described above, in turn with a belt pulley clutch according to one of the designs described above, a refrigerant compressor (preferably a Refrigerant compressor of a vehicle air conditioning system), an electric generator unit, and a refrigerant compressor and generator unit with an output shaft of an internal combustion engine and belts that are coupled to one another, wherein in a disengaged/open position of the belt pulley clutch (1) (ie in a position in which the start - / Boost pawl and the generator pawl are not in positive contact with the flange and/or pulley) the generator unit is initially reduced to a low positive or even negative (first) speed and then the generator unit is accelerated briefly ung (by increasing the speed to a second speed that is higher than the first speed) on the belt, so that the pulley clutch at least by means of its start / boost pawl rotationally connects the pulley (in the first direction of rotation) to the flange and then the generator unit by further acceleration the now coupled Verbr the engine starts / starts. This further simplifies the switching behavior.

In other words, the invention relates to a pulley clutch, in particular with ratchet freewheels, for decoupling the pulley from the crankshaft (output shaft) so that the air conditioning compressor can be driven by the starter generator when the internal combustion engine (combustion engine) is stationary. During normal operation of a drive, the belt pulley clutch should be permanently closed and transmit torque in both effective directions. Furthermore, it should be possible to open the pulley clutch from a standstill, so that the pulley can be rotated in both directions of rotation relative to its hub.

In order not to provide an additional actuator for actuating the belt pulley clutch, it is proposed, in addition to a centrifugal mechanism, which, in the case of a ratchet freewheel with ratchets for both torque directions and a common inner and outer ring, actuates the ratchets for transmitting the torque in a first torque direction, a second mechanism to be provided, which actuates the pawls for the transmission of the moment in a second moment direction. The second mechanism uses strong acceleration of the belt pulley as a switching signal. An inertial mass is connected to a belt pulley via an over-center spring. The torsion of the inertial mass relative to the pulley is used to actuate the pawls. Due to the over-center spring, there are two stable switching states in the end positions, namely "boost pawl activated" and "boost pawl deactivated". With regard to the advantages over other known switchable pulleys, it should be mentioned in particular that the pulley clutch, which is actuated without an actuator, means that no cable and no plug and no control output stage of an actuator is required, since the "actor" in this invention is the belt starter with its cable and plug, which is already present . In addition, there is no need to attach an additional actuator to the internal combustion engine, which is an advantage in terms of assembly and adjustment and attachment parts. The advantages over electric air conditioning compressors (without belt drive) should be mentioned that no extra electric machine is required for an electric compressor, since the starter generator that is already present fulfills this task. The useful area of application of this belt pulley clutch is in particular plug-in hybrids, since they can drive off electrically and the starting of the combustion engine has more time and there is also a greater need for e-air conditioning because the combustion engine is often switched off.

The clutch / belt pulley clutch is permanently closed during normal operation of a drive and transmits torque in both effective directions. It can be opened from a standstill and can then no longer transmit torque in any effective direction. When the clutch is open, the belt pulley can be rotated in both directions relative to its hub/to the flange. The clutch is actuated by the e-machine already in the vehicle/the generator unit on the belt drive by means of inertia and centrifugal actuation and intelligent control, in particular speed, torque and time specifications. Furthermore, a component-friendly and safe switching is possible.

The invention is explained in more detail below on the basis of a preferred exemplary embodiment, also with the aid of drawings.

• 1 bis 3 in schematischer Art eine erfindungsgemäße Riemenscheibenkupplung, wobei in der 1 der Motorstartbetriebszustand und das Schalten in den Standklimabetriebszustand dargestellt ist, wohingegen in der 2 der Normalbetriebszustand und in der 3 der Standklimabetriebszustand dargestellt sind,
• 4 und 5 den grundsätzlichen Aufbau der erfindungsgemäßen Riemenscheibenkupplung, wobei in der 4 eine Längsschnittdarstellung und in der 5 eine perspektivische Darstellung eines Teils der erfindungsgemäßen Riemenscheibenkupplung aus 4 gezeigt ist,
• 6 und 7 eine Frontansicht der Riemenscheibenkupplung der 4 und 5 im Motorstartbetriebszustand und eine vergrößerte Ansicht des Bereichs VII aus 6,
• 8 und 9 eine Ansicht der Riemenscheibenkupplung der 4 und 5 in dem Normalbetriebszustand, bei der eine Umdrehungszahl von größer 800 U/min vorliegt, wobei in 9 eine vergrößerte Darstellung des Bereichs IX aus 8 wiedergegeben ist, und
• 10 und 11 eine zu den 6 und 7 vergleichbare Darstellung der Riemenscheibenkupplung gemäß der 4 und 5, nun aber im Standklimabetriebszustand.

The show

• 1 until 3 in a schematic way a pulley clutch according to the invention, wherein in the 1 the engine starting operating state and switching to the stationary climate operating state is shown, whereas in FIG 2 the normal operating state and in the 3 the stationary climate operating status is shown,
• 4 and 5 the basic structure of the pulley clutch according to the invention, wherein in the 4 a longitudinal section and in the 5 a perspective view of a part of the pulley clutch according to the invention 4 is shown
• 6 and 7 a front view of the pulley clutch of FIG 4 and 5 in engine starting mode and an enlarged view of area VII 6 ,
• 8th and 9 a view of the pulley clutch of FIG 4 and 5 in the normal operating state, in which the number of revolutions is greater than 800 rpm, with in 9 an enlarged view of area IX 8th is reproduced, and
• 10 and 11 one to the 6 and 7 comparable representation of the pulley clutch according to the 4 and 5 , but now in stationary climate mode.

The figures are only of a schematic nature and serve only to understand the invention. The same elements are provided with the same reference numbers.

In 1 a pulley clutch 1 according to the invention is shown.

It has a pulley 2 which has a hub 3 . There is also a flange 4 embodied as a bow spring flange 5 . The arc spring flange 5 can be driven via an output shaft 6, designed as a crankshaft, of an internal combustion engine, which is not shown here for the sake of clarity. A plurality of start/boost pawls 7 are pivotably connected to the hub 3 (also referred to as the inner ring) of the belt pulley 3 . Only one of the start / boost pawls 7 is in the 1 until 3 shown.

Also is in the 1 until 3 a generator latch 8 shown. Basically, a large number of generator latches 8 are installed, the same number as start/boost latches 7.

There is also a centrifugal weight arrangement forming centrifugal actuation means 9 . The centrifugal actuating means 9 uses a flyweight 10 and a return spring 11 . There is also an inertial mass arrangement which forms an inertial actuating means 12 . The inertia actuating means 12 employs a mass ring 13 and an over center spring 14 . An actuating element 15 is connected between the flyweight 10 and the generator pawl 8 on the one hand and the mass ring 13 and the start/boost pawl 7 on the other hand. A leaf spring 16 basically pushes the two pawls 7 and 8 in the direction of the arc spring flange 5. If the actuating elements 15 allow this, the distal ends of the pawls 8 engage in latching contours 17 on the flange 4.

The mass ring 13 also has a locking contour 18 . In 2 it can be seen that the centrifugal weight 10 blocks the mass ring 13 . In 3 , the auxiliary air conditioning mode, is different than in 2 shown normal operation, to recognize that the Massering13 the centrifugal weight 10 locks.

Such a blocking is in the engine start mode or when switching to the stationary air conditioning mode, as in 1 shown does not exist.

In 1 a schematic representation of the pulley clutch 1 is shown. A rotary movement in the direction of motor rotation corresponds to an upward movement in the schematic representation. The center of rotation would be to the left of the plot. Centrifugal forces act correspondingly to the right.

In the 2 shows the switching state before a belt start or before switching to stationary air conditioning mode. The start/boost pawl 7 of the formed pawl freewheel is meshed and engages in the latching contour 17 of the arc spring flange 5 . If a torque is now transmitted from a belt starter generator (generator unit, not shown) in the direction of engine rotation via the belt, not shown, to the belt pulley 2, a compressive force acts on the engaged pawl 7, which thus moves the arc spring flange 5 and thus the crankshaft 6 of the internal combustion engine / the Internal combustion engine rotated.

With increasing speed, a centrifugal force acts on the centrifugal weight 10, which is in equilibrium with the restoring force of the restoring spring 11. Above a critical speed, which should be below the idling speed of the internal combustion engine, the state is reached as in the 2 is shown. The centrifugal weight 10 is pivoted outwards and has released the generator pawl 8 via the actuating element 15 assigned to it. Moment / torque can now be transmitted in both effective directions (generator and boost).

In 2 It can also be seen that the centrifugal weight 10 pivoted outwards prevents the mass ring 13 from moving in the circumferential direction and thereby the start/boost pawl 7 folds away.

If the internal combustion engine is now stopped, the centrifugal weight 10 pivots inwards again. The status appears again 1 a.

If you now want to switch to stationary air conditioning mode, belt pulley 2 must be accelerated in the opposite direction to the direction of rotation of the combustion engine. In the schematic representation, this corresponds to a downward movement. The mass ring 13 is also accelerated, but only by the force that is exerted on the mass ring 13 by the over-center spring 14 . If the backward acceleration of the belt pulley 2 is correspondingly greater, then there is a relative rotation between the belt pulley 2 and the mass ring 13. This relative rotation is used to use the actuating element 15, which is connected to the mass ring 13, to activate the start/boost pawl 7 to disable. The final state after switching is in 3 shown. Thus, according to the invention, after the internal combustion engine has been switched off in order to disengage the stationary air conditioner, the generator unit will exert a brief, high first acceleration on the belt of the belt drive, thereby completely opening the belt pulley clutch 1 . The generator unit then drives the belt, which is decoupled from the output shaft 6, up to an operating speed of the refrigerant compressor by means of a second acceleration, which is less than the first acceleration.

In 3 it can be seen that the switched mass ring 13 blocks the centrifugal weight 10 in its inner position. The belt pulley 2 is completely decoupled from the crankshaft 6 in this state. The generator unit can now drive the ancillary units, in particular an air conditioning compressor, by slowly increasing the speed in the forward or reverse direction of rotation via the belt.

If the internal combustion engine is now to be started again, the start/boost pawl 7 must be engaged again. This takes place via a strong acceleration of the belt pulley 2 in the direction of rotation of the internal combustion engine. The speed of the pulley 2 can be reduced beforehand, and even a low speed can be set in the reverse direction. Reducing the speed reduces the speed at which the pawls 7 or 8 engage in the latching contour 17 of the arc spring flange 5, which reduces the stress on the component/noise development. Switching to start the engine is the same as switching to stationary air conditioning mode, only with the opposite direction of acceleration. According to the invention, the generator unit is first reduced/braked to a low positive or even negative speed for re-engagement when the engine is started in a disengaged position of the pulley clutch 1 . Following this, the generator unit is then briefly accelerated strongly in that its speed is greatly increased. A short, strong acceleration is thus also exerted on the belt, so that the pulley clutch 1 connects the pulley 2 to the flange 4 in rotation, at least by means of its start/boost pawl 7, and the generator unit then starts the now coupled combustion engine through further acceleration.

The mass ring 13 is accelerated by the force of the over dead center spring 14 . If the acceleration of the belt pulley 2 is correspondingly greater, a relative rotation of the mass ring 13 relative to the belt pulley 2 occurs again, as a result of which the start/boost pawl 7 is engaged again. The pulley clutch 1 is now back in the state as in 1 shown. The combustion engine can be started.

In the 4 until 6 is about the schematic of the 1 until 3 addition, a specific embodiment of the pulley assembly / pulley clutch 1 is shown.

In the 4 is a longitudinal sectional view through a belt pulley 2 according to the invention. The belt pulley 2 is rotatably mounted on a primary mass of an arc spring damper via a ball bearing. The primary mass can be screwed to the crankshaft 6 . The arc spring flange 5 is located inside the arc spring damper. The pawls 7 and 8 are arranged between the arc spring flange 5 and the hub 3 of the belt pulley 2 outside the sectional plane. The mass ring 13 is screwed to a mount 19 . The receptacle 19 is rotatably mounted on the belt pulley 2 by means of a ball bearing. Furthermore, a multi-part passage 20 is connected to the receptacle 19, the actuating elements 15 for switching the pawls being arranged on its outer circumference. The over-center spring 14 is also hung on the mass ring receptacle, the second attachment point of which is formed by a groove in a bolt 21 of the joint of the centrifugal weights 10 . The bolts 21 of the joint of the centrifugal weights 10 are in turn screwed into the flange of the pulley 2.

Coupling plates 22 are also used.

In the 5 the pulley 2 is shown from the crankshaft bolting side, with the primary mass and arc springs not shown. The representation corresponds to the state of normal operation. The pawls 7 and 8 engage in the latching contours 17 of the arc spring flange 5 .

A support bracket is provided with the reference number 23 and a blocking contour with the reference number 24.

the 6 until 11 show the different operating states, according to the functional diagrams 1 until 3 . The mass ring 13 is shown partially in section, and the centrifugal weight 10 of the actuating mechanism of the generator pawl 8 can be seen. A section through the ratchet freewheel is also shown in a detailed representation. The detailed representation is in the 7 , 9 and 11 played back.

the 6 until 11 do not show all of the components used in a belt pulley clutch 1 according to the invention.

In 6 and 7 the mass ring 13 is in the position in which the start/boost pawl 7 is engaged. The centrifugal weights 10, which are coupled by means of a coupling plate 22 that is preloaded via return springs 11, are pivoted inwards. The coupling plate 22 is screwed to a penetration, which is also in the 4 you can see.

The over dead center spring 14 is clamped between the bolt 21 of the joint of the centrifugal weight 10 and a bearing point on the receptacle of the mass ring 13 . In the mass ring 13, the locking contour 24 is attached. A pin 26 (also referred to as a locking element), which is part of the centrifugal weight, engages in this blocking contour 24 . As soon as the centrifugal weight 10 pivots outwards, the mass ring 13 is fixed in the circumferential direction via the form fit of the pin 26 and locking contour 24 . See also in this regard 8th and 9 . However, if the mass ring is folded into its opposite end position (see e.g. 10 and 11 , the locking contour 24 prevents the centrifugal weights 10 from pivoting outwards under centrifugal force. As a result, a particularly skilful coupling 25 between the centrifugal actuation means 9 and the inertia actuation means 12 is implemented. The inertia actuating means 12 is operatively connected to the centrifugal actuating means 9 by means of the coupling 25, the coupling 25 being designed such that in at least one relative position of the inertial actuating means 12 relative to the centrifugal actuating means 9, the adjustment of the starting/ Boost jack 7 and / or the generator jack 8 prevents. The coupling 25 is also designed in such a way that it allows the start/boost pawl 7 (from the form-fitting engagement with the flange 4) and the generator pawl 8 (from the form-fitting engagement with the flange 4) to be opened/released by the respective actuating means 9, 12 prevented in normal operation. For this purpose, the coupling has the pin 26 on the centrifugal weight 10 together with the locking contour 24 .

If the pin 26 is located at an upper end of the blocking contour 24 formed by a (V-shaped) link path 8th , An inertial actuation, ie a movement of the mass ring 13 in the direction of rotation, is prevented by the blocking contour 24 . The pin 26 is located at a lower end of the locking contour 24 opposite the upper end 10 , the centrifugal weight 10 is in turn inhibited/blocked in its movement by the inertial actuating means 12 .

The pawls 7 and 8 of the freewheel lie on their radially inner end face in a pocket of the hub 3 of the belt pulley 2. In the middle of the pawl 7 and 8, a leaf spring 16 acts.

In 8th and 9 shows the switching state of normal operation at speeds above the idle speed of the internal combustion engine. The centrifugal weights 10 are pivoted outwards and are supported on the inner surface of the mass ring 13 . The centrifugal weights 10 and the mass ring 13 form a friction fit at this point, which prevents rattling due to rotational irregularities of the internal combustion engine.

In the detailed view it can be seen how both pawls 7 and 8 are released by the actuating elements 15 and engaged in the respective latching contours 17 .

In the 10 and 11 shows the switching status of the stationary air conditioning mode. The mass ring 13 is in its second end position. The centrifugal weights 10 are fixed in their inner position via the locking contour 24 . In the detailed view it can be seen how both pawls 7 and 8 are folded inwards by the actuating elements 15 . The torque flow from the belt pulley 2 to the crankshaft 6 is interrupted and the belt pulley 2 can rotate freely.

Both latches 7, 8 are thus folded in for stationary air conditioning. This is followed by a momentary reverse acceleration from a starting position 6 (Pin 26 in the apex area between the upper and lower end) against the inertial mass of the mass ring 13. The vehicle is then slowed down slowly, as otherwise there may be a downshift. In the position of the pin 26 at the lower end of the blocking contour 24, the centrifugal actuation means 9/the centrifugal weights 10 are blocked, as a result of which stationary air conditioning is possible.

To restart from stationary air-conditioning mode, belt pulley 2 is first braked to a single-track speed and switched to counteracting the inertial mass of mass ring 13 by rapid forward acceleration. For a particularly soft start, it is possible to achieve a switchover at approx. 0 rpm by braking down to a negative speed and then accelerating positively. Furthermore, for a soft application of the pawls 7, 8 when bridging the pawl clearance angle, a lower acceleration can be used. This reduces stress and over-tensioning of the decoupler. As soon as the centrifugal force is higher than the restoring spring force of the centrifugal weights 10 due to the speed, the pin 26 reaches the upper end of the locking contour 24 (as in 8th recognizable). In this position of the pin 26, both pawls 7, 8 are locked, ie both pawls 7, 8 are in positive engagement with the hub 3 of the pulley 2 and the flange 4/the arc spring flange 5 (as in 9 recognizable). Thus, in this position, the blocking contour 24 indirectly prevents unwanted shifting at high accelerations.

The belt pulley clutch 1 is used in its operation in a belt drive of a (hybrid) motor vehicle, not shown here for the sake of clarity, the belt drive also having a generator unit/a starter generator, a belt and at least one tensioning unit prepared for tensioning the belt. An air conditioning compressor is also preferably present in the belt drive.

Reference List

1

pulley clutch

2

pulley

3

pulley hub

4

flange

5

arc spring flange

6

crankshaft

7

Start / Boost pawl

8th

generator latch

9

centrifugal actuating means

10

flyweight

11

return spring

12

inertial actuation means

13

ground ring

14

over dead center spring

15

actuator

16

leaf spring

17

locking contour

18

locking contour

19

Mounting of the ground ring

20

passage

21

bolt

22

coupling plate

23

support bracket

24

locking contour

25

coupling

26

pen

Claims (10)

Pulley clutch (1) for the required, detachable torque-transmitting connection of a generator-connected pulley (2) to an output shaft (6) that can be driven by an internal combustion engine, with at least one movable start/boost pawl (7) connected to the pulley (2), which is used to apply torque is prepared for a flange (4) that can be connected to the output shaft (6) in a first direction of rotation in an engine starting mode, with at least one movable generator pawl (8) connected to the belt pulley (2), which is used to apply torque from the flange (4) to the Pulley (2) is prepared in a second direction of rotation opposite to the first direction of rotation in normal operation and/or engine start-up operation, further comprising a centrifugal actuation means (9) and an inertia actuation means (12), characterized in that the centrifugal actuation means ( 9) so in operative relationship with the generator latch (8) is that in a centrifugal force-inactivated position of the centrifugal force actuating means (9), the generator pawl (8) is freed from torque-transmitting engagement with the flange (4), and the inertia actuating means (12) is in operative relationship with the start/boost pawl (7), that the start/boost pawl (7) can be brought between a torque-transmitting position with the flange (4) during engine starting operation and during normal operation and a torque-free position during stationary air-conditioning operation due to inertia. Pulley clutch (1) after claim 1 , characterized in that the inertia actuating means (12) can be preloaded into two stable positions by an over-center spring (14). Pulley clutch (1) after claim 1 or 2 , characterized in that the inertial actuation means (12) has a mass ring (13) with an outer contour matched to a flyweight (10) of the centrifugal actuation means (9). Pulley clutch (1) after claim 3 , characterized in that the switching positions of the mass ring (13) and the centrifugal weight (10) and the outer contour of the mass ring (13) and the outer contour of the centrifugal weight (10) are coordinated in such a way that the mass ring (13) the centrifugal weight (10) in the centrifugally unactuated position when the start/boost pawl (7) is placed in its torque-free position. Pulley clutch (1) according to one of Claims 1 until 4 , characterized in that the inertial actuation means (12) is operatively connected to the centrifugal actuation means (9) by means of a coupling (25), the coupling (25) being designed such that in at least one relative position of the inertial actuation means ( 12) prevents the adjustment of the start/boost pawl (7) and/or the generator pawl (8) relative to the centrifugal actuation means (9). Pulley clutch (1) after claim 5 , characterized in that the coupling (25) is designed such that it prevents opening of the start / boost pawl (7) and / or the generator pawl (8) by the respective actuating means (9, 12) in normal operation. Pulley clutch (1) according to one of Claims 1 until 6 , characterized in that the inertia actuating means (12) a displacing has an actuating element (15) acting on the start/boost pawl (7) and/or the centrifugal force actuating means (9) has an actuating element (15) which has an adjusting effect on the generator pawl (8). Belt drive for a motor vehicle, with a generator unit, a pulley clutch (1) according to one of Claims 1 until 7 , a belt and at least one tensioning unit prepared for tensioning the belt. Method for operating a belt drive with a belt pulley clutch (1) according to one of Claims 1 until 7 , a refrigerant compressor, an electrical generator unit, and a refrigerant compressor and generator unit with an output shaft of an internal combustion engine and belts that are coupled to one another, whereby after the internal combustion engine is switched off, the generator unit exerts a brief, high first acceleration on the belt of the belt drive and thereby the belt pulley clutch (1st ) opens completely and then the generator unit drives the decoupled from the output shaft belt up to an operating speed of the refrigerant compressor by a second acceleration, which is smaller than the first acceleration. Method for operating a belt drive with a belt pulley clutch (1) according to one of Claims 1 until 7 , a refrigerant compressor, an electrical generator unit, and a refrigerant compressor and generator unit with an output shaft of an internal combustion engine and belts that are coupled to one another, with the generator unit first being reduced to a low positive or even negative speed in a disengaged position of the belt pulley clutch (1) and then the generator unit exerts brief high acceleration on the belt, so that the belt pulley clutch (1) connects the belt pulley to the flange (4) in rotation, at least by means of its start/boost pawl (7), and the generator unit then accelerates further to the now coupled one combustion engine starts.

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