This invention relates to sealing mechanisms and, more particularly, to a ring seal wherein an anti-rotation mechanism is employed.
Many of the current automatic shifting transmissions employ ring seals between rotating parts. These parts generally rotate at different speeds and therefore have hydraulic pressures flowing between the rotating parts. The seal is designed to prevent the leakage of fluid from one side of the seal to the other. In many applications, it is desirable to prevent rotation of the ring seal relative to one of the moving parts.
The prior art has chosen to provide an axially extending tab, which is inserted in an axial slot formed in a shaft to retain the seal from rotating relative to the shaft on which it is mounted. While these seals are effective in preventing axial leakage past the outside diameter of the seal, they are operable in only one direction. The axially extending tab thereof is fitted into an axial slot and therefore does not prevent leakage in a direction toward the slot and tab. Also, the axial slot required for the tab takes up valuable axial space within the assembly in many instances.
It is an object of the present invention to provide an improved ring seal having an anti-rotation structure formed thereon.
In one aspect of the present invention, the ring seal has a radially extending tab.
In another aspect of the present invention, the radially extending tab is formed inwardly of the ring seal and is engageable within a slot formed on the part to which it is assembled.
In yet another aspect of the present invention, the ring seal with a radial tab will seal both the outer diameter and both sides of the ring thereby preventing fluid from passing in either axial direction when a third pressure is present.
Referring to
Referring to
The ring seal 30 has an outer peripheral surface 44 similar to the surface 16 of the ring seal shown in
When fluid pressure is admitted to the space between the shaft 34 and the component 42 from the left side of the seal 30, the fluid will flow under the seal to the inner surface thereof forcing the surface 44 to seal against the component 42 and also forcing the surface 46 to seal against the surface 50. Thus, the pressure within the space between the shaft 34 and component 42 will be maintained free of leakage.
In the event that pressure reversal is necessary, such that fluid pressure is admitted from the right side of the seal 30 while the left side is connected to an exhaust, the outer surface 44 will again seal against the component 42 and the side surface 48 will seal against the side 52 of the groove 32. Thus, the seal will have integrity in both directions and will not consume any excess axial space for assembly requirements.