Patent Application
20110005629
This invention generally relates to a relief valve for a vehicle component that allows bi-directional flow through the relief valve.
Driveline slip yokes for drive shaft assemblies include a plug that is inserted into an open end face near a universal joint. The slip yoke has an internal bore at the open face that includes a splined surface that mates with a spline shaft member. The plug covers exposed ends of the splines. Traditionally, the plug includes a central circular hole that is defined by an axis parallel to a centerline of the splines. This hole compensates for pressure generated within the slip yoke due to axial movement of the spline shaft member within the internal bore.
When the spline shaft member moves outward to extend the length of the drive shaft assembly, a vacuum is created within a cavity that is formed between an end of the spline shaft member and the plug. Similarly, when the spline shaft member moves inward to shorten the length of the drive shaft assembly, pressure is formed within the cavity between the end of the spline shaft member and the plug. The central circular hole in the plug allows for movement of air inward and outward to equalize pressure between the outside and inside the slip yoke assembly. If the spline shaft member is moved outwardly, the slip shaft assembly can become contaminated at the spline shaft member seal interface because of the vacuum created in the cavity. If the increase of atmospheric pressure is not equalized when the spline shaft member is moved inward, the plug inserted in the end of the slip yoke can be pushed out of position, which would expose the splines to potential contamination in addition to allowing leakage of lubricating fluids.
One disadvantage with this current configuration is that that with the current circular hole configuration, the hole itself is a leak path for external contaminants such as water, salt, dirt, etc. Thus, there is a need for an improved slip yoke plug configuration.
A vehicle component includes a plug and relief valve that that allows bi-directional flow for venting purposes while preventing external contaminates from entering an internal cavity of the vehicle component.
In one example, a slip yoke assembly includes a slip yoke with a plug received within an open end. The relief valve is mounted within the plug and allows bi-directional flow for venting purposes while preventing external contaminates from entering the slip yoke.
In one example, the relief valve has at least one elongated passage extending through a flexible membrane that is movable between a venting position and a sealed position.
In one example, the relief valve includes an attachment portion formed about an outer periphery which serves to seat the relief valve within an opening formed within the plug. In one example the attachment portion comprises a groove. The flexible membrane is located radially inwardly relative to the groove.
In one example, the at least one elongated passage comprises an elongated slit. A single slit can be used or a plurality of slits can be used. When venting, flaps of the slit open to allow equalization of air pressure on either side of the plug. When closed, the flaps of the slit contact each other to provide a sealed interface that prevents contaminants from entering the internal cavity of the vehicle component.
In another example, a brake assembly includes a brake component with the plug relief valve that allows bi-directional flow for venting purposes while preventing external contaminates from entering an internal cavity of the brake component.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
A plug 28 is installed within the slip yoke 10, and the relief valve 14 is supported by the plug 28. The slip shaft body 16 includes an internal central bore 30 that includes a mating splined surface 32 that connects to the splined surface 24 of the shaft 22. The central bore 30 is closed at one end by the shaft 22 and is open at an opposite shaft end near the yoke portion 18 as indicated at 34. The relief valve 14 is supported in the plug 28 by the slip yoke 10 near the yoke portion 18 to enclose the central bore 30 at the open end 34.
The relief valve 14 is shown in greater detail in
An edge of the plug 28 seats within a groove 50 formed at the open end 34 of the slip yoke 10. The plug 28 comprises a rigid, non-flexible member, which is made of metal or plastic for example. Further, the plug 28 can comprise a curved or flat member.
The relief valve 14 includes a thin, flexible membrane 52 that is located radially inwardly of the attachment portion 40. The flexible membrane 52 includes at least one elongated passage 56 that extends axially across the flexible membrane 52. The elongated passage 56 is defined by a length dimension that extends in a direction that is non-parallel to the central yoke axis A.
The relief valve 14 is made from a non-corrosive, generally flexible material such as rubber or other polymer materials for example. This allows the relief valve 14 to be easily installed within the plug 28 and provide movement of the flexible membrane 52.
In the example shown in
The flexible member 52 allows bi-directional flow through the relief valve 14 to equalize the atmospheric differential pressures within a cavity 66 (
It should be understood that while a single elongated passage 56 is shown, the flexible membrane 52 could include multiple elongated passages 56 as shown in
Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.
