WO2016173707A1

WO2016173707A1 - Auxiliary unit drive device

Info

Publication number: WO2016173707A1
Application number: PCT/EP2016/000664
Authority: WO
Inventors: Timm BRÖCKER; Tom MACHT
Original assignee: Volkswagen Aktiengesellschaft
Priority date: 2015-04-28
Filing date: 2016-04-27
Publication date: 2016-11-03
Also published as: EP3289191A1; DE102015005344A1; EP3289191B1

Abstract

The invention relates to an auxiliary unit drive device (1) having a planetary gear (2), two auxiliary units (3, 4), wherein the two auxiliary units (3, 4) can be driven by means of a drive via the planetary gear (2). The fuel consumption can be reduced by virtue of the fact that the two auxiliary units (3, 4) are designed as oil pumps (12, 13).

Description

Accessory drive device

The invention relates to an auxiliary drive device with the features of claim 1.

From DE 42 00 918 C1 a generic auxiliary drive device of a motor vehicle is known. The accessory drive device has a differential in the form of a planetary gear. The planetary gear has a ring gear, a planet carrier and a sun gear. A crankshaft of the motor vehicle is connected to the planet carrier, wherein the ring gear and the sun gear each serve as an output for each auxiliary unit. Serving as an alternator three-phase generator is connected to the ring gear. A water pump is connected to the sun gear of the planetary gear. The ring gear is connected via a belt transmission with the alternator. The sun gear is connected via another belt drive with the water pump. The alternator and the water pump form ancillaries, which are driven by the internal combustion engine via the planetary gear. Between the output of the planetary gear and the water pump, a locking device is arranged, which shut down the water pump at a cold start. The locking device is designed as an electromagnetic clutch. When the electromagnetic clutch brakes the water pump, the speed of the alternator is increased. During a cold start of the internal combustion engine, a controller is supplied with a signal dependent on the cooling water temperature. With a cold engine, only little or no cooling water throughput is desired. The on-board voltage induced in the alternator depends directly on the drive speed of the alternator. When the rotational speed of the crankshaft is low, a high gear ratio can be achieved, so that the electric demand is covered even at an idling speed. On the other hand, a lowering of the transmission ratio at high engine speeds is possible. The alternator can be operated in a favorable efficiency range of their characteristic field.

Furthermore, oil pumps for motor vehicles are known in the prior art. Oil is conveyed by means of the oil pump from an oil sump to lubrication points of the internal combustion engine. The oil pump is driven by the internal combustion engine of the motor vehicle via the crankshaft.

CONFIRMATION COPY The generic state of the art is not yet optimally formed. When driving the ancillaries friction losses can occur, which can lead to increased fuel consumption.

The invention is therefore based on the object to design the generic ancillary drive device such and further, so that the fuel consumption can be reduced.

This object of the invention is now achieved by an auxiliary drive device with the features of claim 1.

The two ancillaries are designed as oil pumps. As a result, the mechanical drive power to the oil supply of the internal combustion engine can be reduced. With the help of the planetary gearbox, the two oil pumps are driven. Depending on the state ratio of the planetary gear and the input speed both oil pumps can be operated variable in number depending on each other. The two oil pumps can optionally be operated at different speeds. The total delivery volume can be adapted to the needs. By an appropriate choice of geometrical delivery volumes, an adjustment of the total delivery volume flow and the oil pressure to the current needs of the internal combustion engine can be made substantially at constant input speed of the drive, namely the corresponding crankshaft. The drive is formed in particular by the internal combustion engine of the motor vehicle. The drive power required for oil supply can be reduced as needed. The oil pumps can be operated in an efficiency-optimized range. As a result, the friction loss can be reduced.

In a particularly preferred embodiment, the speed variation of the two oil pumps via a control valve. The speed variation is set via the control valve. The two oil pumps can be controlled or controlled by means of the control valve. In a first position of the control valve promotes the second oil pump and the first oil pump is. In a second position of the control valve is the second oil pump and the first oil pump delivers. When the first oil pump is stopped, the second oil pump rotates at the maximum possible speed. When the second oil pump is stopped, the first oil pump rotates at the maximum possible speed. As a result, different oil pressure levels can be realized. In the first position, the control valve blocks the flow through the first oil pump. The control valve locks in the first position, in particular the flow through one of the first oil pump associated pressure line. The flow through a second oil pump zugeordnet pressure line and the flow through a second oil pump associated with the suction line is released in the first position.

In the second position, the control valve allows the flow through the first oil pump. The control valve opens in the second position in particular the flow through the first oil pump associated pressure line. The flow through the second oil pump zugeordnet pressure line and / or the flow through the second oil pump associated with the suction line is locked in the second position. The fact that the suction line is locked, prevents oil from the pump runs back into the oil sump. Due to the oil held in the second oil pump, the second oil pump is blocked.

The planetary gear is preferably driven via the ring gear. The ring gear is drivingly coupled to the crankshaft. The first oil pump is preferably non-rotatably connected to the sun gear of the planetary gear. The second oil pump is rotatably connected to the planet carrier. The second oil pump serves as a brake. If the planet carrier is held by means of the second oil pump, then the sun gear rotates at maximum speed. The first oil pump is driven at maximum speed. When the control valve is located in the second position, the suction line and the brake pressure line are closed, the second oil pump does not rotate. If the actuating piston is moved to the end position of the first position, the suction line and the pressure line of the brake are released and the pressure line of the first oil pump is closed. The second oil pump or brake starts to rotate and the first oil pump slows down. When the actuating piston has reached the end position of the first position, the first oil pump is complete and only the second oil pump rotates and delivers.

The control valve is in particular pressure-actuated, wherein the voltage applied to the outlet of the two oil pumps oil pressure is returned to the control valve via a control line. The output of the oil pumps form corresponding pressure lines. The control valve is spring loaded against this oil pressure. If the force due to the oil pressure is less than the spring force, then the control valve is arranged in the first position, wherein the first oil pump is stationary and the second oil pump delivers. If the force due to the oil pressure is greater than the spring force, then the control valve is disposed in the second position, wherein the second oil pump is and promotes the first oil pump. The first oil pump is coupled in a preferred embodiment with a sun gear and the second oil pump is coupled to a planet carrier. The drive is coupled to a ring gear. The drive is formed by a crankshaft of the motor vehicle. The crankshaft may be coupled via an intermediate gear with the ring gear.

In one embodiment, one of the oil pumps is coupled to a vacuum pump. The coupled with the vacuum pump oil pump and the vacuum pump are formed by a tandem pump. This has the advantage that, in particular in the low speed range of the drive negative pressure can be provided. In the upper speed range, the oil pump, which is not coupled to the vacuum pump, can take over the essential delivery component and, in particular, can be operated alone. Further advantages over a vacuum pump driven by a separate electric drive are that the design as a tandem pump is cheaper than the electric drive, and the power consumption is lower than when using a conventional vacuum pump.

In particular, the first oil pump may be coupled to the vacuum pump. The oil pump coupled to the vacuum pump is operatively coupled to the sun gear. The coupled with the vacuum pump oil pump is functionally effective driven by the sun gear. The vacuum pump runs at the speed of the sun gear, since the oil pump coupled to the vacuum pump is functionally effective driven by means of the sun gear and the drives of this oil pump and the vacuum pump are coupled. At low speeds of the crankshaft is the planet carrier and the vacuum pump and the first oil pump promote with the corresponding maximum pump speed as a function of the respective crankshaft speed. As the engine speed increases, the speed of the sun gear decreases and the speed of the planet carrier increases. At higher drive speeds, the pump speed of the first oil pump and the vacuum pump is reduced and the planet carrier drives the second oil pump with increasing speed. The coupled with the vacuum pump, the first oil pump and the vacuum pump thus have a sinking with increasing speed of the drive pump speed. In the upper speed range, coupled with the vacuum pump, first oil pump can be stopped or operated only at low speed. The vacuum pump is driven at the same speed as the coupled oil pump or by means of a ratio with a proportional speed. The Dauerlauffähigkeit the vacuum pump is thereby increased. There are now a variety of ways to design and further develop the accessory drive device according to the invention. For this purpose, reference may first be made to the claims subordinate to claim 1. In the following, a preferred embodiment of the invention will now be explained in more detail with reference to the drawing and the associated description. In the drawing shows:

Fig. 1 in a highly schematic representation of a

Auxiliary drive device with a planetary gear and two ancillary units in the form of a first oil pump and a second oil pump,

2 is a schematic detail of a part of an oil circuit with the two oil pumps and a control valve, wherein the flow is blocked by the second oil pump,

3 is a schematic detail of the part of the hydraulic circuit of FIG. 2, wherein the flow through the first oil pump is blocked,

Fig. 4 is a schematic representation of another

Auxiliary drive device with a planetary gear, two oil pumps and a vacuum pump, and

Fig. 5 is a schematic diagram of a delivery volume plotted on a

Engine speed.

In Fig. 1, an accessory drive device 1 is shown for a motor vehicle. The accessory drive device 1 has a planetary gear 2. Furthermore, two ancillaries 3, 4 are provided. The two auxiliary units 3, 4 are by means of a drive (not shown in detail) via the planetary gear 2 drivable. The drive is designed in particular as an internal combustion engine of the motor vehicle. By means of the internal combustion engine, a crankshaft 5 is driven with a torque M. The crankshaft 5 is mounted in a housing 6.

The planetary gear 2 has a ring gear 7, a planet carrier 8 with a plurality of planetary gears (not shown in detail) and a sun gear 9. The planet gears are rotatably mounted on the planet carrier 8. The planet gears are now in one meshing engagement with the internal toothing of the ring gear 7 and the other in meshing engagement with the external toothing of the sun gear. 9

In a preferred embodiment, the crankshaft 5 is rotatably connected to the ring gear 7. The crankshaft 5 drives the ring gear 7. The ring gear 7 forms the drive member (unspecified) of the planetary gear 2. The first auxiliary unit 3 is rotatably connected via a shaft 10 with the sun gear 9. Concentric with the shaft 10, a hollow shaft 11 is arranged, wherein the hollow shaft 11 rotatably connects the second auxiliary unit 4 with the planet carrier 8. The planet carrier 8 drives the second auxiliary unit 4.

The aforementioned disadvantages are now avoided by the fact that the two ancillaries 3, 4 are designed as oil pumps 12, 13. The first auxiliary unit 3 is formed by a first oil pump 12 and the second auxiliary unit 4 is formed by a second oil pump 13.

This has the advantage that the mechanical drive power for conveying the oil can be reduced. The delivery volume can be adapted to the needs of the internal combustion engine by the speed variability of the planetary gear 2. With the help of the planetary gear 2, the two oil pumps 12, 13 are driven. Depending on the state ratio of the planetary gear 2 and the input speed of the crankshaft 5, both oil pumps 12, 13 are operated variable in number depending on each other.

When the first oil pump 12 is stopped, the second oil pump 13 rotates at the maximum possible speed. When the first oil pump 12 rotates at maximum speed, is the second oil pump 13. By an appropriate choice of geometric delivery volumes, an adjustment of the total delivery volume flow to the current oil demand, regardless of the input speed of the crankshaft 5 are made.

The two oil pumps 12, 13 may be of identical construction. In an alternative embodiment, the oil pumps 12, 13 are formed differently. The oil pump 12 and / or the oil pump 13 may be formed, for example, as gear pumps or as vane pumps.

The two oil pumps 12, 13 each have a rotor, wherein the rotor with the corresponding shaft 10 and the hollow shaft 11 is connected. The two Oil pumps 12, 13 promote oil from a common oil sump 14. The oil is thereby conveyed from the oil sump 14 via the two oil pumps 12, 13 to the internal combustion engine 15. Each of the oil pumps 12, 13 is a suction line 16, 18 and a pressure line 17, 19 assigned. The oil pump 12 is associated with a suction line 16 and a pressure line 17. The oil pump 13 is a suction pipe 18 and a pressure pipe

19 assigned.

As shown in FIGS. 2 and 3, the accessory drive device 1 further includes a control valve 20. The control valve 20 has a plurality of unspecified ports. A first pressure line section 17a can be connected to a second pressure line section 17b of the pressure line 17 by means of the control valve 20, or these two pressure line sections 17a, 17b can be separated from one another by means of the control valve 20. The pressure line 17 of the first oil pump 12 is blocked by the control valve 20 and apparently.

By means of the control valve 20, the pressure line 19 of the second oil pump 13 is also lockable and apparently. The pressure line 19 has two pressure line sections 19a and 19b, wherein the two pressure line sections 19a, 19b are connectable and separable by means of the control valve 20. The pressure line section 19a is connected to an input of the control valve

20 and the pressure line section 19b is connected to an output of the control valve 20.

Further, by means of the control valve 20, the suction line 18 can be locked and apparently. The suction line 18 has two Saugleitungsabschnitte 18a, 18b, wherein the two Saugleitungsabschnitte 18a, 18b connected by means of the control valve 20 and are separable from each other.

In the position of the control valve 20 shown in FIG. 2, the pressure line 18 and the suction line 19 of the second oil pump 13 are blocked. Since the pressure line 19 and the suction line 18 are locked, is the second oil pump 13. In this second position of the control valve 20, the pressure line 17 of the first oil pump 12 is opened. The first oil pump 12 runs at maximum speed and maximum delivery volume.

In the first position of the control valve 20 shown in FIG. 3, both the suction line 18 and the pressure line 19 of the second oil pump 13 are opened by means of the control valve 20. The pressure line 17 of the first oil pump 12 is by means of Control valve 20 locked. As a result, the first oil pump 12 is braked and the second oil pump 13 rotates and delivers.

When the control valve 20 is moved from the second position (Fig. 2) to the first position (Fig. 3), the suction line 18 and the pressure line 19 of the previously working as a second brake oil pump 13 and the pressure line 17 of the first oil pump 12 is closed. The second oil pump 13 starts to deliver, with the first oil pump 12 rotating more slowly.

When the control valve 20 has reached the end position shown in FIG. 3, the first oil pump 12 stands and only the second oil pump 13 rotates.

The control valve 20 is pressure-actuated, the oil pressure applied at the outlet or in the pressure line sections 17b, 19b of the two oil pumps 12, 13 being fed back to the control valve 20 via a control line 21. The control valve 20 is spring-loaded, and when the force due to the oil pressure is smaller than the spring force, the control valve 20 is disposed in the first position (FIG. 3). In the second position shown in Fig. 2 is a high oil pressure to the control line 21, so that the spring is compressed. When the force due to the oil pressure is greater than the spring force, the control valve 20 is disposed in the second position (FIG. 2). This results in the control depending on the oil pressure. In the illustrated in Fig. 3 basic position or first position is a low oil pressure 21, wherein the spring force is sufficient to move the actuating piston in the first position.

Due to the translation of the planetary gear 2 so different delivery levels of the oil pumps 12, 13 can be adjusted. There are two levels of pressure achievable. The drive power required for the oil supply can be reduced as needed without changing the crankshaft speed. As a result, the fuel consumption necessary for oil supply can be reduced.

It is possible to reverse the direction of rotation of one of the two oil pumps 12, 13 or both oil pumps 12, 13 to use the corresponding oil pump 12, 13 for sucking the oil from the internal combustion engine.

In Fig. 3, an accessory drive device 22 is shown. The accessory drive device 22 is similar to the Ancillary drive device 22 constructed, now the same reference numerals are used for substantially functionally identical parts.

The ancillary drive device 22 also has a planetary gear 2 and two ancillaries 3, 4 in the form of oil pumps 12, 13. The planetary gear 2 has a ring gear 7, a planet carrier 8 and a sun gear 9. The ring gear 5 is functionally effective via the crankshaft 5 driven. The crankshaft 5 is coupled via a module drive 23 with the ring gear 7. The module drive 23 consists essentially of a non-rotatably mounted on the crankshaft 5 gear 24, an intermediate 25 and a further gear 26, wherein the gear 26 in particular rotatably on a hollow shaft 27 is arranged. About the hollow shaft 27, the ring gear 7 is driven. The sun gear 9 drives the first oil pump 12 via a first pump shaft 28. The planet carrier 8 drives the second oil pump 13 via a second pump shaft 29.

In the preferred embodiment shown here, one of the oil pumps 12, 13, namely, in particular, the first oil pump 12 is operatively coupled in terms of drive technology to a vacuum pump 30. The vacuum pump 30 is operatively coupled to the pump shaft 28 via an intermediate shaft 31. The vacuum pump 30 may serve, for example, to supply a brake booster or the like. The coupled to the vacuum pump 30, first oil pump 12 and the vacuum pump 30 are functionally effective by means of the sun gear 9 drivable.

The first oil pump 1 1 and the vacuum pump 30 are operated at the same pump speed. The pump speed of the second oil pump 13 differs in particular from the speed of the first oil pump 12 and thus also the speed of the vacuum pump 30. The coupled with the vacuum pump 30, the first oil pump 12 and the vacuum pump 30 have a sinking with increasing speed of the drive pump speed. The second oil pump 13 has an increasing pump speed with increasing speed of the drive. In the range of the maximum speed of the drive, it is conceivable that the first oil pump 12 and the vacuum pump are substantially and the second oil pump 13 is operated alone. In the low speed range is promoted mainly by means of the first oil pump 12 and thereby the vacuum pump 30 is driven, as in particular in the low speed range pumping capacity of the vacuum pump 30 is required. Preferably, the accessory drive device 22 is operated such that the vacuum pump 30 does not or only at low speed rotates at high speeds. This increases the endurance capability of the vacuum pump 30 and serves the consumption reduction. In Fig. 5 different delivery volume over the engine speed, ie the speed of the crankshaft 5 are plotted. It is a maximum delivery volume 32, a minimum delivery volume 33 and a demand curve 34 of an internal combustion engine shown. The total delivery volume V _Ges results from the sum of the delivery _{volumes of} the first oil pump 12 V _Pumpe1 and the second oil pump 13 Vp _umpe2 . The minimum flow volume 32 adjusts itself when the planet carrier is 8, ie when the rotation speed n _P i _anete nträger equal to zero revolutions per minute and thus the first oil pump 12 is running at maximum speed. The minimum delivery volume 33 results when the sun gear is, that is, when substantially only the second oil pump 13 is driven and the speed of the sun gear n _Son ne equal to zero revolutions per minute.

It can be clearly seen that the demand curve 34 lies between the maximum delivery volume 32 and the minimum delivery volume 33 for all illustrated engine speeds. At high engine speeds while the demand curve 34 is closer to the minimum delivery volume 33, so by adjusting the total delivery volume V _Ges to the demand curve 34, the first oil pump 12 has little or no promotion to meet the need.

LIST OF REFERENCE NUMBERS

Accessory drive device

planetary gear

accessory

crankshaft

casing

ring gear

planet carrier

sun

wave

hollow shaft

oil pump

oil sump

internal combustion engine

suction

pressure line

a pressure line section

b pressure line section

suction

a suction line section

b suction line section

pressure line

a pressure line section

b pressure line section

control valve

control line

Accessory drive device

module drive

gear

idler

gear

hollow shaft

pump shaft

pump shaft Vacuum pump intermediate shaft

maximum delivery volume minimum delivery volume Demand characteristic

Claims

PATEN TA NSPR CHE

1. ancillary drive device (1, 22) with a planetary gear (2), with two ancillary units (3, 4), wherein the two ancillaries (3, 4) by means of a drive via the planetary gear (2) can be driven, characterized in that the two ancillary units (3, 4) as oil pumps (12, 13) are formed.

2. ancillary drive device according to claim 1, characterized in that the two oil pumps (12, 13) by means of a control valve (20) are controllable or controllable, wherein in a first position of the control valve (20), the first oil pump (12) and the second Oil pump (13) promotes, in a second position of the control valve (20), the first oil pump (12) promotes and the second oil pump (13).

3. ancillary drive device according to claim 2, characterized in that by means of the control valve (20), the pressure line (17, 19) and / or the suction line (18) of the first oil pump (12) or the second oil pump (13) are closable and obvious.

4. ancillary drive device according to one of the preceding claims 2 or 3, characterized in that the control valve (20) is pressure-actuated, wherein the output of the two oil pumps (12, 13) applied oil pressure to the control valve (20) via a control line (21) is returned.

An accessory drive device according to any of the preceding claims 2 to 4, characterized in that the control valve (20) is spring-loaded, wherein when the force due to the oil pressure is less than the spring force, the control valve (20) is arranged in the first position, wherein, when the force due to the oil pressure is greater than the spring force, the control valve (20) is arranged in the second position.

6. An accessory drive device according to one of the preceding claims, characterized in that the first oil pump (12) is coupled to a sun gear (9), the second oil pump (13) is coupled to a planetary carrier (8) and the drive is coupled to a ring gear (7) is.

7. Auxiliary drive device according to one of the preceding claims, characterized in that the drive is formed by a crankshaft (5) of a motor vehicle.

8. ancillary drive device according to one of the preceding claims, characterized in that one of the oil pumps (12) with a vacuum pump (30) is coupled.

9. ancillary drive device according to the preceding claim, characterized

in that the oil pump (12) coupled to the vacuum pump (30) and the vacuum pump (30) descend with increasing speed of the drive

Have pump speed.

10. ancillary drive device according to the preceding claim, characterized

characterized in that the with the vacuum pump (30) coupled to the oil pump (12) is functionally effective by means of the sun gear (9) driven.