Transfer case having a lubrication guide

Patent metadata

Field	Value
Publication number	US-10274074-B1
Application number	US-201816036254-A
Country	US
Kind code	B1
Filing date	Jul 16, 2018
Priority date	Jul 16, 2018
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

A transfer case having a lubrication guide with an inlet, an outlet and an elongated tubular portion that is disposed between the inlet and the outlet. The lubrication guide is coupled to a drive assembly that transmits rotary power between a pair of output shafts such that the inlet is disposed proximate a first rotary component of the drive assembly to receive splash lubrication (i.e., slung lubrication and/or surge lubrication) therefrom.

First claim

What is claimed is:

1. A transfer case comprising:
a housing defining an internal cavity;
a first output shaft received in the internal cavity and supported by the housing for rotation about a primary axis;
a second output shaft received in the internal cavity and supported by the housing for rotation about a secondary axis;
a drive assembly transmitting rotary power between the first and second output shafts; and
a lubrication guide disposed in the internal cavity and having an inlet, an outlet and an elongated tubular section disposed between the inlet and the outlet, the lubrication guide being coupled to the drive assembly such that the inlet is disposed proximate a first rotary component of the drive assembly to receive splash lubrication therefrom when rotary power is transmitted between the first and second output shafts to drive the second output shaft in a predetermined rotational direction and at a speed in excess of a predetermined rotational speed;
wherein the inlet is disposed closer to the second output shaft than the outlet; and
wherein when the transfer case is disposed in a baseline operating position, the outlet is vertically below the inlet.

2. The transfer case of claim 1 , wherein the inlet has a first end, which is open, and a second end that is attached to the elongated tubular section, and wherein the inlet converges between the first end and the second end.

3. The transfer case of claim 2 , wherein the drive assembly comprises a first sprocket, which is driven by the first output shaft, a second sprocket, which is coupled to the second output shaft for rotation therewith, and a chain that is engaged to the first and second sprockets.

4. The transfer case of claim 3 , wherein the first rotary component is the second sprocket.

5. The transfer case of claim 3 , wherein the drive assembly further comprises a clutch for selectively transmitting rotary power between the first output shaft and the first sprocket.

6. The transfer case of claim 5 , wherein the clutch is a friction clutch.

7. The transfer case of claim 1 , wherein the first output shaft has a helically grooved portion and wherein the outlet is in fluid communication with the helically grooved portion.

8. The transfer case of claim 7 , wherein the drive assembly further comprises a clutch and a clutch actuator, and wherein the helically grooved portion of the first output shaft is configured to transport lubrication to the clutch and the clutch actuator.

9. The transfer case of claim 8 , wherein the clutch actuator comprises a rotatable ball-ramp ring, a non-rotatable ball-ramp ring and a plurality of balls between the rotatable and non-rotatable ball-ramp rings, and wherein the non-rotatable ball-ramp ring defines a fluid port that extends between the outlet and the helically grooved portion of the first output shaft.

10. A transfer case comprising:
a housing defining an internal cavity;
a shaft disposed in the internal cavity and supported by the housing for rotation about a primary axis;
a clutch received in the housing and having a clutch hub, which is coupled to the shaft for rotation therewith, a clutch basket, a plurality of first clutch plates, a plurality of second clutch plates, and a pressure plate, the first clutch plates being axially slidably but non-rotatably mounted to the clutch hub, the second clutch plates being axially slidably but non-rotatably mounted to the clutch basket, the pressure plate being non-rotatably but axially slidably mounted to one of the clutch hub and the clutch basket;
a clutch actuator having a rotatable ball-ramp ring that is disposed about the shaft, a non-rotatable ball-ramp ring that is disposed about the shaft, and a plurality of balls between the rotatable and non-rotatable ball-ramp rings; and
a lubrication guide disposed in the internal cavity and mounted to the non-rotatable ball-ramp ring, the lubrication guide having an inlet, an outlet and an elongated tubular section disposed between the inlet and the outlet, the lubrication guide being oriented such that the inlet is positioned to receive splash lubrication when rotary power is transmitted through the clutch in a predetermined rotational direction and at a speed in excess of a predetermined rotational speed;
wherein the shaft has a helically grooved portion and wherein the outlet is in fluid communication with the helically grooved portion.

11. The transfer case of claim 10 , wherein the helically grooved portion of the shaft is configured to transport lubrication to at least one of the clutch and the clutch actuator.

12. The transfer case of claim 11 , wherein the clutch actuator further comprises an apply plate, which abuts the pressure plate, a thrust bearing, which is disposed between the apply plate and the rotatable ball-ramp ring, and a sleeve that is non-rotatably coupled to the non-rotatable ball-ramp ring.

13. The transfer case of claim 12 , wherein the sleeve defines a lubrication port that receives a portion of the lubrication that is transported by the helically grooved portion of the shaft, wherein the portion of the lubrication transmitted through the lubrication port lubricates the thrust bearing.

14. The transfer case of claim 12 , wherein the sleeve extends into an annular chamber in the clutch hub, wherein a plurality of lubrication apertures extend radially outwardly from the annular chamber and through a splined surface onto which the first clutch plates are mounted, and wherein lubrication discharged from the helically grooved portion of the shaft into the clutch hub is transmitted through the lubrication apertures to the first and second clutch plates.

15. The transfer case of claim 10 , wherein the inlet has a first end, which is open, and a second end that is attached to the elongated tubular section, and wherein the inlet converges between the first end and the second end.

Assignees

• Borgwarner Inc

Inventors

• Alexiou Arie
• Eldred Jason P
• Worcester Ian D
• Bedi Gurmeet Singh

Classifications

• F16H57/0409

  characterised by increasing efficiency, e.g. by reducing splash losses · CPC title

• B60K2023/0875

  with mechanical means only · CPC title

• F16H57/0473

  Friction devices, e.g. clutches or brakes · CPC title

• F16H57/0457

  Splash lubrication · CPC title

• B60K23/0808

  for varying torque distribution between driven axles, e.g. by transfer clutch · CPC title