Motion sensor lens structure for a building controller

An assembly for sensing motion in a space, comprising:

• a housing;
• a motion sensor for sensing motion in front of the housing;
• a transmitter for transmitting one or more signals that are based at least in part on the motion sensed by the motion sensor to a building automation system;
• a lens member including a lens and a lens mounting structure, the lens member is mounted with the lens exposed to outside of the housing and positioned in front of the motion sensor, the lens comprises high density polyethylene (HDPE) and is configured to direct incoming infra-red (IR) electromagnetic radiation to the motion sensor;
• a bracket situated inside of the housing, the bracket defining an aperture in registration with the motion sensor for passing incoming IR electromagnetic radiation from the lens to the motion sensor;
• the bracket further defining a lens securement aperture and a lens securement spring;
• the lens mounting structure comprising a side wall that extends backward from the lens and around a perimeter of the lens to add rigidity to the lens member, the lens mounting structure also comprising a lens retention hook that extends backward from the side wall and through the lens securement aperture to engage a back side of the bracket;
• and
• wherein the lens securement spring is sufficiently resilient to deflect away from the lens retention hook to enable the lens retention hook to extend past the lens securement spring, but is biased into contact with the lens retention hook to keep the lens retention hook engaged with the back side of the bracket.

A heating, cooling and ventilation (HVAC) controller configured to provide one or more control signals to an HVAC system, the HVAC controller comprising:

• a housing;
• a user interface that is accessible from outside of the housing;
• a motion sensor for sensing motion in front of the housing;
• a controller operatively coupled to the user interface and the motion sensor, the controller configured to provide one or more control signals to the HVAC system that are based at least in part on the motion sensed by the motion sensor;
• a bracket disposable within the housing, the bracket defining:
• an infrared light aperture configured to permit infrared light to pass through the infrared light aperture;
• a first lens securement aperture on a first side of the infrared light aperture;
• a first lens securement spring extending into the first lens securement aperture;
• a second lens securement aperture on a second side of the infrared light aperture;
• and
• a second lens securement spring extending into the second lens securement aperture;
• the motion sensor is secured relative to the bracket and operably coupled to the controller, the motion sensor configured to detect motion relative to the HVAC controller;
• and
• a lens disposed in front of the motion sensor and configured to direct incoming infra-red light to the motion sensor, the lens including a first lens retention hook that extends into the first lens securement aperture and a second lens retention hook that extends into the second lens securement aperture;
• wherein the first lens securement spring exerts a biasing force in a first direction against the first lens retention hook and the second lens securement spring exerts a biasing force in a second direction again the second lens retention hook, where the second direction is opposite the first direction.