Churning loss reduction means for gear type devices

• US 5,505,112 A
• Filed: 02/18/1994
• Issued: 04/09/1996
• Est. Priority Date: 02/18/1994
• Status: Expired due to Fees

• Current Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Original Assignee: Eaton Corp. (Wisconsin) (Eaton Corporation PLC.)
• Inventors: Gee, Thomas A.
• Primary Examiner(s): LUONG, VINH
• Application Number:
  US08/199,381
• Time in Patent Office: 781 Days
• Field of Search: 74/606 R, 74/467, 74/468, 184/6.12, 184/11.1, 180/339
• US Class Current: 74/606.00R
• CPC Class Codes: F16H 48/08 comprising bevel gears
• CPC Class Codes: F16H 57/0409 characterised by the problem to increase efficiency, e.g. by reducing splash losses
• CPC Class Codes: F16H 57/0423 Lubricant guiding means mounted or supported on the casing, e.g. shields or baffles for collecting lubricant, tubes or pipes means for guiding lubricant into an axial channel of a shaft F16H57/0426; lubrication by injection, injection nozzles or tubes therefore F16H57/0456
• CPC Class Codes: F16H 57/0447 Control of lubricant levels, e.g. lubricant level control dependent on temperature
• CPC Class Codes: F16H 57/0453 Section walls to divide a gear sump
• CPC Class Codes: F16H 57/0457 Splash lubrication characterised by the problem reducing losses, e.g. splash losses F16H57/0409
• CPC Class Codes: F16H 57/0483 Axle or inter-axle differentials
• CPC Class Codes: F16H 57/0493 Gearings with spur or bevel gears differentials with spur or bevel gears F16H57/0483
• CPC Class Codes: Y10T 74/19991 Lubrication
• CPC Class Codes: Y10T 74/19995 Teeth
• CPC Class Codes: Y10T 74/2186 Gear casings

Abstract

A gear device such as a change gear transmission of the countershaft (21) type in which, mounted for rotation about the countershaft is a larger gear (17) and a smaller gear (29). The transmission housing (11) defines a first lubricant reservoir (R1), having a nominal fill level (L1), which is able to lubricate the smaller gear as it rotates. A partition member (51) is disposed around the larger gear and defines a second lubricant reservoir (R2) through which the larger gear passes as it rotates. The partition member defines fluid passages (71,73) providing restricted communication from the first reservoir to the second reservoir. The fluid passages (71,73) are sized such that as the larger gear rotates, carrying lubricant out of the second reservoir (R2), there is maintained in the second reservoir a second fill level (L2), below the first fill level (L1) such that at least a portion of the teeth of the larger gear (17) pass just below the second fill level as the larger gear rotates. The result is substantially reduced churning losses, without decreasing the ability to lubricate the smaller gears.

Claims

1. In a gear type device of the type including housing means defining an axis of rotation, shaft means disposed on said axis of rotation;

a first, relatively smaller gear and a second, relatively larger gear, both of said first and second gears being disposed about said shaft means for rotation about said axis of rotation and each of said gears including an array of teeth;

said housing means including a lower, reservoir-defining portion operable, when full of fluid, to define a first lubricant fluid reservoir, defining a nominal fill level, such that the teeth of said first, relatively smaller gear pass just below said nominal fill level of fluid in said first reservoir as said first gear rotates about said axis of rotation (A);

said gear device comprising a change gear mechanical transmission including a first, lower countershaft, and a second, upper countershaft, said shaft means comprising said first, lower countershaft;

characterized by;

(a) partition means disposed within said lower, reservoir-defining portion of said housing means, and operable to define a second lubricant fluid reservoir through which said second, relatively larger gear passes as said second gear rotates about said axis of rotation;

(b) said partition means defining fluid passage means providing restricted fluid communication from said first lubricant reservoir to said second lubricant reservoir; and

(c) said fluid passage means being sized such that, as said second gear rotates carrying lubricant fluid from said second lubricant reservoir, said restricted fluid communication maintains said second lubricant reservoir at a second fill level, lower than said nominal fill level, such that at least a portion of the teeth of said second, relatively larger gear pass just below said second fill level as said second gear rotates about said axis of rotation.

2. A gear device as claimed in claim 1, characterized by the teeth of said first, relatively smaller gear passing just below said nominal fill level of fluid in said first reservoir, as said first gear rotates about said axis of rotation.

3. In a gear type device of the type including housing means defining an axis of rotation, shaft means disposed on said axis of rotation;

a first, relatively smaller gear and a second, relatively larger gear, both of said first and second gears being disposed about said shaft means for rotation about said axis of rotation and each of said gears including an array of teeth;

said housing means including a lower, reservoir-defining portion operable, when full of fluid, to define a first lubricant fluid reservoir, defining a nominal fill level, such that the teeth of said first, relatively smaller gear pass just below said nominal fill level of fluid in said first reservoir as said first gear rotates about said axis of rotation (A);

said axis of rotation of said gear device defining a downward angle relative to a horizontal plane, said second relatively larger gear being disposed forwardly, and upwardly, from said first, relatively smaller gear;

characterized by;

(a) partition means disposed within said lower, reservoir-defining portion of said housing means, and operable to define a second lubricant fluid reservoir through which said second, relatively larger gear passes as said second gear rotates about said axis of rotation;

(b) said partition means defining fluid passage means providing restricted fluid communication from said first lubricant reservoir to said second lubricant reservoir; and

(c) said fluid passage means being sized such that, as said second gear rotates carrying lubricant fluid from said second lubricant reservoir, said restricted fluid communication maintains said second lubricant reservoir at a second fill level, lower than said nominal fill level, such that at least a portion of the teeth of said second, relatively larger gear pass just below said second fill level as said second gear rotates about said axis of rotation.

4. A gear device as claimed in claim 3, characterized by the teeth of said first, relatively smaller gear passing just below said nominal fill level of fluid in said first reservoir, as said first gear rotates about said axis of rotation.