Dual ring configuration for a stationary seal

摘要

In a piston-ported engine, a sealing ring may be placed in a groove in the cylinder. As the groove is of greater diameter than the cylinder, the sealing ring overlaps into a helix allowing it to be enter the cylinder. However, such a helix does not fit into a groove without when in the helix. Alternatively, a shorter sealing ring is placed into the groove. However, the gap is too large. According to one embodiment, a groove of double the width of the ring is provided and the helical ring is installed and caused to unwind in the groove so that the ring sits in a plane. A spacer ring is placed in the groove to fill the extra space in the groove. An elastomeric material or a tension spring in an outer groove in the sealing ring can be used to cause the ring to press against the piston.

主权项

1. A piston and cylinder assembly, comprising
a cylinder having an annular cylinder groove defined in an inner surface of the cylinder; a split sealing ring installed in the cylinder groove, the split sealing ring having a compressed state in which ends of the split sealing ring to overlap to size the split sealing ring for receipt within the cylinder and an expanded state within the cylinder groove in which the ends of the split sealing ring are proximate each other; and a split spacer ring installed in the cylinder groove adjacent to the split sealing ring, the split spacer ring having a compressed state in which ends of the split spacer ring are proximate each other to size the split spacer ring for receipt within the cylinder and an expanded state within the cylinder groove in which the ends of the split spacer ring are separated by a gap.