Apparatus and method for lubricating and cooling gear mechanisms

• US 20060076193A1
• Filed: 10/17/2005
• Published: 04/13/2006
• Est. Priority Date: 04/17/2003
• Status: Active Grant

• Current Assignee: Volkswagen AG
• Original Assignee: Volkswagen AG
• Inventors: Ruther, Thomas, Wilken, Martin
• Granted Patent: US 7,172,054 B2
• Time in Patent Office: Days
• US Class Current: 184/6.120
• CPC Class Codes: F01M 1/08 Lubricating systems characterised by the provision therein of lubricant jetting means
• CPC Class Codes: F16H 57/0434 relating to lubrication supply, e.g. pumps arrangement of pumps F16H57/0441; Pressure control grooves with pumping effect for supplying lubricant F16H57/0428; generation and variation of line pressure for transmission control F16H61/0021
• CPC Class Codes: F16H 57/0456 Lubrication by injection; Injection nozzles or tubes therefor oil mist or spray lubrication F16H57/0458
• CPC Class Codes: F16N 2210/12 Gearings
• CPC Class Codes: F16N 7/38 with a separate pump; Central lubrication systems

Abstract

A device for lubricating and cooling gear mechanisms has a supply line for supplying lubricating and coolant oil from an oil sump into a first channel in a spray pipe. The first spray channel connects to at least one first nozzle for the targeted spraying of the lubricating and coolant oil into areas of the gear that require extensive lubrication and that are allocated to the first channel. The supply line is connected to a second channel and one or more second nozzles connected to the latter for spraying the oil in areas that require extensive lubrication and are allocated to the second channel. The channels are prioritized with regard to more or less critical regions of the gear mechanism. A control valve that is responsive to a back-pressure in the spray pipe actuates the channels to supply the gear mechanism in accordance with the prioritization of the regions.

Claims

1. An apparatus for lubricating and cooling a gear mechanism, comprising:

a feed line for feeding lubricating and cooling oil from an oil sump;

a spray tube having a first channel formed therein communicating with said feed line;

at least one first nozzle communicating with said first channel for targeted spraying of the lubricating and cooling oil into lubrication-intensive regions of the gear mechanism associated with said first channel;

said spray tube having at least one second channel formed therein communicating with said feed line;

at least one second nozzle communicating with said second channel for targeted spraying of the lubricating and cooling oil into lubrication-intensive regions of the gear mechanism associated with said second channel; and

a control valve for selectively switching said first and second channels by back-pressure acting thereupon in a first valve position, wherein said first channel is active and said second channel is closed, and a second valve position, wherein said first channel is active and said second channel is active.

2. The apparatus according to claim 1, wherein the lubrication-intensive regions assigned to said first and second channels are assigned mutually different priorities including a higher-order first priority and a lower-order second priority, and wherein said nozzles for spraying into regions of said higher-order first priority communicate with said first channel and said nozzles for spraying into regions of said lower-order second priority communicate with said second channel.

3. The apparatus according to claim 1, which comprises a bypass communicating with the oil sump, and a pressure-limiting valve configured to open said bypass when a predefined threshold pressure is exceeded, for releasing excess lubricating and cooling oil into the oil sump.

4. The apparatus according to claim 3, wherein said control valve is additionally configured as a pressure-limiting valve.

5. The apparatus according to claim 1, wherein said nozzles are connected to said spray tube through a plug-in connection.

6. The apparatus according to claim 1, wherein at least one of said nozzles is a tubular nozzle extending to the lubrication-intensive region.

7. The apparatus according to claim 1, wherein at least one of said nozzles is a round nozzle configured to spray in a round or conical shape.

8. The apparatus according to claim 1, wherein at least one of said nozzles is a fan-type nozzle configured to spray in a shape of a fan.

9. The apparatus according to claim 1, wherein the lubrication-intensive regions included a tooth engagement of defined gearwheel pairs of adjacent shafts.

10. The apparatus according to claim 1, disposed to lubricate and cool a dual clutch transmission.

11. A method of lubricating and cooling a gear mechanism, the method which comprises:

feeding lubricating and cooling oil from an oil sump via a feed line to a first channel of a spray tube;

spraying the lubricating and cooling oil in a targeted manner, through at least one first nozzle connected to the first channel, into first lubrication-intensive regions of the gear mechanism assigned to the first channel;

feeding lubricating and cooling oil to at least one second channel via the feed line;

spraying the lubricating and cooling oil in a targeted manner, through at least one second nozzle connected to the second channel, into second lubrication-intensive regions of the gear mechanism assigned to the second channel; and

switching a control valve communicating with the first and second channels by way of a back-pressure acting thereon into a first valve position, wherein the first channel is connected to the feed line while the second channel is closed, and into a second valve position, wherein the second channel is connected in addition to the first channel.

12. The method according to claim 11, which comprises:

defining tooth engagements of gear wheel pairings for critical gears of the gear mechanism as lubrication-intensive regions of a higher-order first priority;

spraying the lubricating and cooling oil into the lubrication-intensive regions of the first priority via the first channel and through the nozzles assigned thereto;

spraying the lubricating and cooling oil into lubrication-intensive regions of a lower-order second priority via the second channel and through the nozzles assigned thereto; and

opening only the first channel with the control valve during critical driving situations in dependence on a volumetric flow and/or of a back pressure in the feed line or in the spray tube.

13. The method according to claim 12, which comprises:

during critical driving situations and on occasion of low volumetric flow and/or low back pressure caused by small available amounts of oil, supplying with preference the lubrication-intensive regions of gear wheel pairings for critical gears of the first priority with lubricant and coolant by closing the second channel;

opening the second channel when the volumetric flow and/or back pressure is sufficient; and

when a predefined back pressure is exceeded, opening a bypass for releasing excess lubricant and coolant into the oil sump.