Inertial balance system for a de-orbiting scroll in a scroll type fluid handling machine

A balance system for a scroll type fluid handling machine having a housing with a front section and a rear section;

• a fixed scroll with an end plate and a wrap in the rear section of the housing;
• an orbital scroll with an end plate and a wrap that cooperates with the fixed scroll to displace fluid;
• an orbital scroll drive including a crankshaft rotatably journaled in the front section of the housing and selectively connected to the orbital scroll to drive the orbital scroll in an orbital path or to rotate without driving the orbital scroll;
• and a balance system including a cylindrical member which surrounds a portion of the crankshaft, rotates with the crankshaft and has a central axis that is parallel to the axis of rotation of the crankshaft, a first balance weight assembly journaled on the cylindrical member and having an arm that extends radially inward through a slot in the cylindrical member and engages the crankshaft, a second balance weight assembly journaled on the cylindrical member and having an arm that extends radially inward through a slot in the cylindrical member and engages the crankshaft, and an actuator connected to the cylindrical member and operable to displace the cylindrical member relative to the crankshaft and rotate the first and second balance weight assemblies about the axis of the cylindrical member.

A balance system for a scroll type fluid handling machine having a housing with a front section and a rear section;

• a fixed scroll with an end plate and a wrap in the rear section of the housing;
• an orbital scroll with an end plate and a wrap that cooperates with the fixed scroll to displace fluid;
• an orbital scroll drive including a crankshaft rotatably journaled in the front section of the housing and connected to the orbital scroll by a bushing assembly;
• a bushing assembly shifter that is operable to change a radius of the orbit scroll orbit;
• and a balance system including a cylindrical member which surrounds a portion of the crankshaft, rotates with the crankshaft and has a central axis that is parallel to the axis of rotation of the crankshaft, a first balance weight assembly journaled on the cylindrical member and having an arm that extends radially inward through a slot in the cylindrical member and engages the crankshaft, and an actuator connected to the cylindrical member and operable to displace the cylindrical member relative to the crankshaft and rotate the balance weight assembly about the axis of the cylindrical member.