WO2017042014A1

WO2017042014A1 - Belt drive of an internal combustion engine, and internal combustion engine

Info

Publication number: WO2017042014A1
Application number: PCT/EP2016/069649
Authority: WO
Inventors: Andreas Kellner
Original assignee: Robert Bosch Gmbh
Priority date: 2015-09-11
Filing date: 2016-08-18
Publication date: 2017-03-16
Also published as: DE102015217368A1

Abstract

The invention relates to a belt drive of an internal combustion engine, comprising a first belt pulley (21), a second belt pulley (22), and a traction means (20) connecting the first and second belt pulley (21, 22). In the first belt pulley (21), a coupling is integrated, wherein the coupling is a friction coupling (10) and has a first friction surface (11) and a second friction surface (12), and wherein the first belt pulley (21) is of hollow design, and the first friction surface (11) is provided at an inner jacket area of the first belt pulley (21).

Description

Description title

Belt drive of an internal combustion engine and internal combustion engine state of the art

The present invention relates to a belt drive of an internal combustion engine and an internal combustion engine with belt drive.

In the prior art, for example, ancillary components such as an alternator such as an alternator, a water pump, an air conditioning compressor or a vacuum pump are driven by a belt directly from an internal combustion engine in vehicles. As a result, in particular a high efficiency in the drive of such ancillaries can be achieved. However, one disadvantage is that when the internal combustion engine is at a standstill, e.g. by a start-stop system or during a sailing phase of the vehicle, the

Ancillaries also stand still. This can for example cause disadvantages in an air conditioning system of the vehicle or a cooling of the internal combustion engine. Alternatively, one or more of the accessories could be electrically powered by an electric drive. As a result, however, additional energy must be provided by the electric drive. Furthermore, one or more electric drives also increase the weight of the vehicle.

Disclosure of the invention

The belt drive according to the invention of an internal combustion engine with the

Features of claim 1, on the other hand, has the advantage that a switchability of the belt drive, i. switching on or off the

Belt drive, is possible. In this case, the belt drive according to the invention has a particularly simple and inexpensive construction. In addition, the belt drive according to the invention is virtually maintenance-free and is very robust, so that it over a lifetime of the engine completely remains operational. This is inventively achieved in that the belt drive a first and second pulley and the two

Includes pulleys connecting traction means. In the first pulley, a clutch is integrated, which according to the invention is a friction clutch and has a first and a second friction surface. The first pulley is hollow and the first belt surface is provided on an inner jacket portion of the pulley. As a result, a number of components of the clutch can be reduced. By integrating the friction clutch in the first pulley a particularly compact design is also achieved.

The dependent claims show preferred developments of the invention.

The friction clutch particularly preferably has a structure corresponding to a drum brake of a vehicle. Particularly preferably, the

Friction clutch thereby at least a first and a second jaw, wherein the second friction surface of the friction clutch is formed on the inner shell region of the first pulley facing surfaces of the first and second jaw. The friction clutch according to the invention in the manner of a drum brake has the further advantage that no adjustment device is necessary, since during operation no slip and thus no lining wear, such as. in a drum brake during braking, to decelerate a vehicle occurs. Therefore, no adjustment device or the like must be provided in the friction clutch.

More preferably, the friction clutch is in the non-actuated state in the open state. That when not in operation, the friction clutch is disengaged. Further preferably, the friction clutch further comprises a hydraulic connection, a first piston connected to the first jaw and a second piston connected to the second jaw. In this case, the first and second pistons are arranged on a common hydraulic chamber. Once a

Hydraulic fluid flows into the common hydraulic space, the two pistons are moved radially outward, so that the friction clutch is engaged. Particularly preferably, a valve element is provided in order to establish or interrupt a connection of a hydraulic pressure supply circuit to the hydraulic chamber.

More preferably, the friction clutch comprises a restoring element, in particular a spring element. The restoring element brings the second friction surface of the first friction surface out of engagement.

Preferably, the first and second jaws of the friction clutch are connected to each other via a support bearing. The support bearing is preferably with a shaft,

in particular an output shaft of the internal combustion engine, connected.

Furthermore, the present invention relates to an internal combustion engine arrangement comprising an internal combustion engine and a belt drive according to the invention.

Preferably, the internal combustion engine arrangement is designed such that an output shaft of the internal combustion engine is connected to the friction clutch. Particularly preferably, the output shaft is connected to the first and second jaw of the friction clutch. The friction clutch is for one

Ineingriffbringen, preferably with a hydraulic pressure supply circuit of the internal combustion engine, connectable. A particularly compact design is possible when the output shaft of the internal combustion engine a

Hydraulic channel, through which a hydraulic fluid can be supplied to the friction clutch.

More preferably, a valve element in a supply line from

Hydraulic pressure supply circuit of the internal combustion engine provided for friction clutch. The valve element is arranged to connect the

Release friction clutch with the hydraulic pressure supply circuit of the engine and lock.

More preferably, the second pulley of the belt drive with an electric machine and / or at least one accessory of the

Internal combustion engine, in particular a stator / generator machine, a water pump, a vacuum pump and / or an air compressor, connected. Thus, according to the invention one or more or all

Auxiliary units by establishing a connection via the friction clutch in first pulley are operated or disconnected by interrupting the connection of the internal combustion engine and are operated by means of the electric machine.

More preferably, the friction clutch according to the invention has a

Hydraulic accumulator over which a function of the friction clutch, i. engagement of the friction clutch is possible when the internal combustion engine is at a standstill.

drawing

Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. In the drawing is:

Figure 1 is a schematic view of a

Internal combustion engine arrangement according to an embodiment of the invention,

Figure 2 is a schematic representation of a belt drive with

Friction clutch of an internal combustion engine arrangement of Figure 1, and

Figure 3 is a schematic representation of a belt drive with

Friction clutch according to a second embodiment of the invention.

Preferred embodiments of the invention

Hereinafter, with reference to Figures 1 and 2 a

Internal combustion engine arrangement 1 according to a first preferred

Embodiment of the invention described in detail.

As can be seen from the schematic overview of FIG. 1, the internal combustion engine arrangement 1 comprises an internal combustion engine 3 and a belt drive 2. The belt drive 2 comprises a belt 20 as traction means first pulley 21 and a second pulley 22. The belt 20 connects the first pulley 21 with the second pulley 22.

The first pulley 21 is connected via an output shaft 4 with a

Internal combustion engine 3 connected. The second pulley 22 is with

Ancillaries connected. In this embodiment, the

Auxiliary units an electric machine 7 and an air compressor 6.

The output shaft 4 of the internal combustion engine 3 drives the first pulley 21, so that torque can be transmitted via the belt 20 and the second pulley 22 to the ancillaries.

According to the invention, a friction clutch 10 is now arranged in the first belt pulley 21.

The friction clutch 10 is constructed in the manner of a drum brake and comprises a first friction surface 1 1 and a second friction surface 12. The first friction surface 1 1 is formed on an inner jacket portion of the first pulley 21. The second friction surface 12 is divided on two surfaces on a first jaw 13 and a second jaw 14. The two jaws 13, 14 are connected to each other via a support bearing 19.

For spreading the jaws, a hydraulic chamber 17 is arranged at the opposite end of the jaws 13, 14 of the support bearing 19.

In this case, a first piston 15 and a second piston 16 in the hydraulic chamber 17 is arranged. The first piston 15 is connected to the first jaw 13 and the second piston 16 is connected to the second jaw 14.

Between the jaws 13 and 14, a return element 8 is also arranged in the form of a tension-spring element.

The hydraulic chamber 17 is connected via a hydraulic line 5 with a

Hydraulic pressure supply circuit of the internal combustion engine 3 connected. The hydraulic line 5 is provided in the output shaft 4 of the internal combustion engine 3. Via a branch line 50, the hydraulic line 5 is then connected to the hydraulic chamber 17. At the hydraulic chamber 1 7, a hydraulic port 18 is provided, on which the stub 50 ends. In the simplest case, the hydraulic chamber 17 is directly connected to the hydraulic circuit of

Internal combustion engine 3 connected. The friction clutch is engaged when the engine 3 is running.

Between the hydraulic pressure supply circuit of the internal combustion engine 3 and the hydraulic chamber 17 of the friction clutch 10, a valve element 9 can also be arranged. The valve element 9 is a three / two-way valve and can connect to the hydraulic pressure supply circuit of

2 shows the connection with the hydraulic circuit of the internal combustion engine, whereby pressure in the hydraulic chamber 1 7 can be performed so that the first and second piston move radially outward to the first and second jaw 13, 14 to be applied to the first friction surface 1 1 on the inner shell portion of the first pulley 21. This is indicated in Figure 1 by the arrows A and B.

In order to disengage the friction clutch 10, the valve element 9 is switched to the second position, so that a connection between the hydraulic chamber 17 and the hydraulic sump 90 is made, so that the pressure in the hydraulic chamber 1 7 decreases. This allows the return element 8, the two pistons 1 5, 16 return to the starting position and the second friction surface 12 on the first and second jaw 13, 14 out of engagement with the first friction surface 1 first

As a result, the friction clutch 10 can be opened even when the engine 3 is running, so that one or more ancillary units on the

Belt drive 2 can be switched off.

FIG. 3 shows a friction clutch 10 according to a second exemplary embodiment of the invention. In contrast to the first embodiment, the

Friction clutch 10 of the second embodiment additionally still a

Memory 30 on. As can be seen from Figure 3, the memory 30 by switching the valve element 9 with the hydraulic chamber 1 7 in conjunction to be brought. Thereby, a pressure in the hydraulic chamber 17 can be increased even when the internal combustion engine 3 is out of operation and a hydraulic pressure of the internal combustion engine is not present to the

Frictional coupling 10 to be engaged. The engagement of the friction clutch 10 then takes place via the pressure stored in the memory 30. As can be seen from Figure 3, the memory 30 via a line 32 in which a check valve 31 is arranged, with the hydraulic supply line 33 from

Hydraulic pressure supply circuit of the internal combustion engine connected. Thus, during operation of the internal combustion engine at a pressure build-up in

Hydraulic pressure supply circuit and the memory 30 is again pressurized and thus stands for a next stoppage of the internal combustion engine, e.g. when a start-stop system of the internal combustion engine turns off before a traffic light or the like, again available.

For the two embodiments, it should also be noted that designed as a three / two-way valve valve element 9 can also be replaced by two 2/2-way valve.

Thus, according to the invention a cost-effective and robust friction clutch in the manner of a drum brake in a belt 21 of a belt drive 2 can be integrated. As a result, no additional space is required for a coupling between the engine and the ancillaries.

In particular, by using the friction clutch 10 in the manner of a drum brake, a known mass production technology can be used as a friction clutch device.

Claims

claims

Belt drive of an internal combustion engine, comprising:

a first pulley (21),

a second pulley (22), and

a traction means (20) connecting the first and second belt wheels (21, 22),

wherein in the first pulley (21) a clutch is integrated, wherein the clutch is a friction clutch (10) and a first friction surface (1 1) and a second friction surface (12), and wherein the first pulley (21) is hollow and the first friction surface (1 1) on an inner cladding region of the first

Pulley (21) is provided.

Belt drive according to claim 1, characterized in that the

Friction clutch (10) at least a first jaw (13) and a second jaw (14), wherein the second friction surface (12) on each of the inner shell region of the first pulley (21) facing surfaces of the first and second jaw (13, 14 ) is arranged.

A belt drive according to claim 2, further comprising a hydraulic chamber (17) and a hydraulic port (18) for connection to a

Hydraulic pressure supply circuit, wherein in the hydraulic chamber (17) a first piston (15) and a second piston (16) is arranged, wherein the first piston (15) with the first jaw (13) is connected and the second piston (16) with the second Jaw (14) is connected.

Belt drive according to claim 3, characterized in that the

Hydraulic chamber (17) by driving a valve element (9) with the hydraulic pressure supply circuit is connectable.

Belt drive according to one of the preceding claims, further comprising a return element (8) which returns the friction clutch (10) to an initial position. Belt drive according to one of claims 2 to 5, characterized in that the first jaw (13) with the second jaw (14) via a support bearing (19) is connected.

Internal combustion engine arrangement, comprising an internal combustion engine (3) and a belt drive (2) according to one of the preceding claims.

Arrangement according to claim 7, characterized in that a

Output shaft (4) of the internal combustion engine (3) with the friction clutch (10) is connected.

Arrangement according to claim 7 or 8, characterized in that the friction clutch (10) with a hydraulic pressure supply circuit of

Internal combustion engine (3) is connected.

Arrangement according to claim 9, characterized in that in the output shaft (4) a hydraulic channel (5) is formed to a

Establish connection to the hydraulic pressure supply circuit of the internal combustion engine (3).

Arrangement according to claim 9 or 10, characterized by a

Valve element (9), which in a connecting line of the

Hydraulic pressure supply circuit of the internal combustion engine (3) with the hydraulic chamber (17) of the friction clutch (10) is arranged to a

Connection of the friction clutch (10) with the

Hydraulic pressure supply circuit of the internal combustion engine to release or lock.

Arrangement according to one of claims 7 to 1 1, characterized in that the second pulley (22) of the belt drive (2) with an electric machine (7), in particular a stator / generator machine, and / or an auxiliary unit (6) of the internal combustion engine connected is.

Arrangement according to one of claims 7 to 12, characterized by a hydraulic accumulator (30) for actuating the friction clutch (10).