The invention relates to a lubricant pump with the features
the preamble of claim 1.
Currently located on the market internal combustion engines is under
Circumstances the need, depending on the engine architecture
the engine lubricant from the cylinder heads
or to suck it out of the turbochargers. In so-called dry sump lubrication
Occasionally, the crank chamber is additionally sucked off.
The need for this is reinforced by the dynamics effects
such as As uphill, cornering, etc .. For this are in
usually hydraulic fixed displacement pumps, in special cases
also used electrically driven suction pumps.
Hydraulic constant-flow pumps can be used, for example, as
Internal or external gear pumps are running
and are usually always driven, so independent
from the real need of suction always the mechanical friction
is to raise. Due to the mechanical friction, the entire
Friction of the internal combustion engine increases and thereby arise
Consumption disadvantages. When using electrically driven pumps
also arise consumption disadvantages, depending on the application
The electric pumps can be switched on as needed
which reduces the consumption penalty. electrical
Suction pumps are associated with very high total costs.
A generic lubricant pump for an internal combustion engine is, for example, from the German patent application, from which this inven tion emanates, the DE 10 2005 029 086 A1
known. In this, a lubricant pump for an internal combustion engine is described for sucking the located in a lubricant collecting device lubricant, with a lubricant pump housing in which at least two pairs of gears are arranged. To form the pump stages, the gear pairs on the suction side are connected to a suction channel formed in the lubricant pump housing and on the pressure side to a pressure channel. In the DE 10 2005 029 086 A1
It is proposed that in the lubricant pump housing, a lubricant supply channel connected to the suction channel of the first pump stage is integrated, via the lubricant to the suction side of the first pump stage is conveyed.
on this, known from the prior art lubricant pump
for an internal combustion engine, it is disadvantageous that
the pump stages run permanently, reducing fuel consumption
the internal combustion engine is increased.
the present invention is to show a measure
with the for a generic lubricant pump
reduces the fuel consumption for the internal combustion engine
The object is achieved by the features in the characterizing part of the claim
Inventive embodiment of the lubricant pump
leads to a reduction of the fuel requirement of the internal combustion engine
as well as cost advantages over the use of an electrical
Lubricant pump or lubricant suction pump.
Design according to claim 2 allows
In addition, advantageously, the active extraction of
Lubricant and passive drainage of lubricant
from the internal combustion engine via a single supply line.
Embodiments according to the claims
3 to 6 are particularly preferred embodiments,
being with the use of a single machine housing
when using the drive shaft of the first pump as the drive shaft
a particularly compact design is possible.
The following is the invention with reference to a particularly preferred embodiment
explained in more detail in a single figure.
1 shows a section through a lubricant pump according to the invention.
1 shows a schematic section through a lubricant pump according to the invention 1 , The lubricant pump 1 points in a machine housing 2 a first pump 3 and a second pump 6 on. The first and the second pump 3 . 6 are each framed by a dashed line. The first lubricant pump 3 is schematically illustrated as a gear pump, with a first gear ZR1 and a second gear ZR2, wherein the first gear ZR1 on a drive shaft 10 , a driving wedge is not shown figured and the second gear ZR2 on an axis 17 is stored. The second pump 6 is also schematically shown as a gear pump by a third gear ZR3 and a fourth gear ZR4. The third gear ZR3 is also on the axis 17 stored. The fourth gear ZR4 is also on the drive shaft 10 stored. The drive shaft 10 has at one of the fourth gear ZR4 protruding end to a switching element 11 corresponding geometry.
The first pump 3 has a first pressure egg th 4 , represented by a cavity, for supplying lubricant to the internal combustion engine with a lubricant pressure P1. In addition, it has a first suction side 5 on, also represented by a cavity, with the lubricant can be sucked on. The second pump 6 has a second pressure side 7 and a second suction side 8th , also each represented by a cavity, on. The second suction side 8th is lubricant leading with a suction channel 9 connected to the suction of lubricant from the internal combustion engine and / or other aggregates such. B. an exhaust gas turbocharger. Next is in the engine case 2 adjacent to the switching element 11 a pressure room 14 provided, which is acted upon by the lubricant pressure P1. This is the first page of printing 4 and the pressure room 14 via a pressure line 18 connectable with each other. The lubricant-carrying pressure line 18 can from a valve 16 , In the present embodiment, a hydraulic valve to be closed, so that in the pressure chamber 14 no lubricant pressure P1 is applied more, but is depressurized.
When the first pump 3 Lubricant promotes and thus builds up the lubricant pressure P1, the switching element 11 , with corresponding position of the valve 16 , acted upon by the lubricant pressure P1 and in the direction of the drive shaft 10 pressed, schematically represented by an arrow, and at the same time is the switching element 11 positive fit with the drive shaft 10 connected. This is the second pump 6 via force and / or positive connection between the drive shaft 10 and the switching element 11 can be switched on via the lubricant pressure P1. In this state, ie when the second pump 6 can be operated via the suction channel 9 Lubricant from the internal combustion engine and / or from other aggregates, such. B. be sucked off an exhaust gas turbocharger. The suction channel 9 is beyond a closure element 13 , which with the pressure room 14 Lubricant leading is connected via the lubricant pressure P1 against a spring force of a spring element 12 closable. The closure element 13 is in the present embodiment, a double piston whose function will be explained below.
Adjacent to the suction channel 9 is still a drain channel 15 provided with the closure element 13 alternately with the suction channel 9 is closable. The drainage channel 15 serves for a non-pressurized return of lubricant from the internal combustion engine or or exhaust gas turbochargers. This means that when operating the second pump 6 the suction channel 9 is opened so that lubricant can be sucked out of the internal combustion engine, while the flow channel 15 is closed. Will the pressure chamber 14 but not acted upon by the lubricant pressure P1, so that the second pump 6 no lubricant promotes, is the suction channel 9 closed at the same time and the drainage channel 15 open. This constellation makes it possible to use the drainage channel 15 as well as the suction channel 9 in the lubricant conveying direction in front of the closure element 13 form as a common lubricant channel.
In other embodiments, the valve 16 also a hydraulic or pneumatic or electric valve 16 be. Preferably, the first and / or the second pump 3 . 6 a vane pump or a gear pump, such. As an internal or an external gear, but other common, known in the art lubricant pumps can be used.
In other words, the invention can be implemented as follows:
From the pressure area, the first pressure side 4 , the first pump 3 the lubricant pressure P1 is removed. If there is a need for suction, then the lubricant pressure P1, for example via a hydraulic control solenoid valve, the switching element 11 in the fourth gear ZR4, the hydraulic suction stage, the second suction side 8th , fed. The pressure P1 generated in the pressure chamber 14 an axial force on the switching element 11 in the fourth gear ZR4 of the second pump 6 , a suction stage. Due to the axial force is on the opposite side of the switching element 11 a frictional and / or positive connection to the drive shaft 10 generated and the suction stage of the second pump 6 begins, due to the frictional and / or positive connection, with the lubricant delivery. The electrical control signal can, for example, be tapped from a characteristic map of an internal combustion engine control system, taking into account signals from the overall vehicle sensor system (inclination, inclination, acceleration, etc.).
Through a targeted coordination of the pressure surfaces in the pressure chamber 14 can be set specifically a defined force, which depends on the respective dimensions of the lubricant pump 1 depends. By additional measures on the friction surfaces of the drive shaft 10 and the switching element 11 the transmittable torque can be influenced, possibly also via positive locking.
In another, not figuratively not shown embodiment is based on a switching element 11 waived. In this case, the pressure P1 can also be applied directly to the fourth gear ZR4, which is arranged axially displaceable. The torque transmitting frictional engagement is then between the fourth gear ZR4 and the drive shaft 10 shown. However, a disadvantage of this embodiment is an increased axial play requirement.
By a suitable choice of material (Alumi nium, RSA ... for the fourth gear ZR4), however, in this embodiment, gap losses, lubricant losses that undesirably reduce the lubricant pressure P1, advantageously again minimized and at the same time the efficiency of the second pump 6 , or the suction stage can be improved. On the opposite side in the pressure room 14 becomes a control valve, the closure element 13 , which activates the drainage channel 15 without lubricant suction closes and the suction channel 9 to the lubricant suction stage, the second suction side 8th , opens.
If there is no need for the extraction of lubricant, the pressurization is interrupted with the lubricant pressure P1, pressure reduction valve via a Druckab reduced the pressure range of the suction and the frictional engagement is interrupted. On the opposite side is in the pressure room 14 by the spring force of the spring element 12 the pressure-free drainage channel opened again and the suction channel 9 locked.
An advantage of positioning the frictional or positive locking in the pressure chamber 14 There is the possibility of dissipating the heat generated by a plurality of switching operations by lubricants or to cool the components by lubricant.
Through the use of the switching element 11 , as shown in the first embodiment, the effects of wear in the torque transmitting friction point is counteracted in an advantageous manner, the switching unit "turns itself after". By the example, conical design of the switching element 11 Advantageously, the frictional force is increased in the form of an increase in the surface normal force. This may possibly be dispensed with Reibwerterhöhende measures.
the simple design and use of a "simple" hydraulic valve
arises over the use of an electric suction pump
a significant cost advantage and not one
switchable Konstantabsaugpumpe a significant consumption advantage.
In summary, the following advantages result in a nutshell:
- - Fuel economy reduction
- - Cost advantages
- lubricant pump
- 2 '
- drive shaft
- switching element
- spring element
- closure element
- pressure chamber
- drain channel
- hydraulic valve
- pressure line
QUOTES INCLUDE IN THE DESCRIPTION
The documents listed by the applicant have been automated
generated and is solely for better information
recorded by the reader. The list is not part of the German
Patent or utility model application. The DPMA takes over
no liability for any errors or omissions.
Cited patent literature
- - DE 102005029086 A1 [0004, 0004]