Window treatment having a spring wrap brake

A brake spring for a motorized roller tube system, the brake spring comprising:

• a plurality of coils having a first tang assembly at a first end of the plurality of coils and a second tang assembly at a second end of the plurality of coils, each of the first tang assembly and the second tang assembly comprising a radially extending tang and a support portion extending from the tang to reduce stress on the tang;
• wherein, in a first rotational position, a first force is exerted on the first tang assembly, thereby back driving the brake spring, reducing an internal diameter of the plurality of coils, to tighten the plurality of coils about a motorized roller tube disposed inside the plurality of coils and halt the rotation of the motorized roller tube;
• and
• wherein, in a second rotational position, a second force is exerted on the second tang assembly sufficient to overcome the first force, increasing the internal diameter of the plurality of coils to loosen the plurality of coils about a motorized roller tube disposed inside the plurality of coils and permit the rotation of the motorized roller tube.

A window treatment, comprising:

• a roller tube for winding a flexible member;
• and
• a drive assembly disposed in the roller tube, the drive assembly comprising a motor, an electronic drive unit, a drive shaft for rotating a puck connected to the roller tube via a puck shaft, and a brake assembly;
• wherein the brake assembly comprises:
• a mandrel;
• an input member coupled to the drive shaft and rotatable around the mandrel;
• an output member coupled to the puck shaft and rotatable around the mandrel;
• a brake spring disposed upon the mandrel, the brake spring comprising:
• a plurality of coils;
• a tang extending from the plurality of coils;
• and
• a support portion extending from the tang in a direction of rotation of the plurality of coils to reduce stress on the tang;
• a second tang extending from the plurality of coils at a distal end of the plurality of coils and a second support portion extending from the second tang;
• wherein, when the motor is not actuated, the brake assembly prevents the flexible member from coming unwound;
• and
• wherein actuation of the motor exerts a force on the second tang, thereby causing the plurality of coils to loosen on the mandrel and allow rotation therebetween, allowing the flexible member to be unwound from the roller tube.