Mechanically actuated tip seals for scroll apparatus and scroll apparatus embodying the same

A method of making a tip seal in an involute scroll fluid apparatus including a scroll member having an involute curved channel including a bottom wall and at least one side wall extending along the axial end of the scroll member, and a tip seal element normally disposed at least in part in said channel above said bottom wall for axial movement therein, comprising the steps of:

• (a) forming the tip seal element so that it has an involute curved configuration substantially matching that of the channel;
• (b) forming the length of the tip seal element so that it is shorter at its inner end than said channel and longer at its outer end than said channel;
• and
• (c) placing the seal element in the channel in its normal, relaxed condition and subsequently torqueing it within the channel to force the inner and outer ends into the channel and to therefore provide a circumferential load on the seal element against a side wall of the channel.

A method of making a tip seal assembly in an involute scroll fluid apparatus including a scroll member having an involute curved channel including a bottom wall and at least one side wall, the channel extending along the axial end of the scroll member, comprising the steps of:

• (a) forming a tip seal element so that it has an involute curvature corresponding to the involute curvature of said channel, the width of the tip seal element being less than the width of the channel to enable the tip seal element to freely move axially within the channel, and also forming the tip seal element so that it is shorter at its inner end than the inner end of the channel and longer at its outer end than the outer end of the channel;
• (b) forming an involute curved sheet metal spring element from spring metal so that the thickness of the sheet metal all lies in substantially the same plane in its relaxed state, with the pitch of the involute curve of the spring element being greater than that of the channel, and with the width of the spring element being substantially greater than the thickness thereof but less than the width of the channel;
• (c) deforming the spring element by bending it in its own plane so that the pitch of its involute curve matches that of the channel, the deformation not exceeding the elastic limit of the spring element but causing it to assume a coned angle along its length;
• (d) placing said spring element adjacent the bottom wall of said channel;
• and
• (e) placing said tip seal element in the channel above the spring element with the seal element deformed to match the involute curve of the channel over the full length of the seal to produce a circumferential load on the seal element against a side wall of the channel, the tip seal normally resting against the spring element with a portion of the tip seal extending axially outwardly of the channel.