Combine harvester with near infrared grain sensor

A combine harvester comprising:

• a cleaning section;
• a grain tank;
• and
• a grain elevator, comprising:
• a paddle loop comprising a plurality of paddles for carrying harvested grain;
• a driver configured to drive the paddle loop and thereby move the paddles upward at a first side of the paddle loop and downward at a second side of the paddle loop, whereby the harvested grain is elevated from a lower point proximate a downstream end of the cleaning section to a higher point proximate a grain inlet of the grain tank;
• an elevator housing encompassing at least a portion of the paddle loop;
• and
• a sensor assembly comprising a NIR sensor for detecting properties of the harvested grain and a sensor window arranged for enabling infrared light to travel between the NIR sensor and the harvested grain;
• wherein:
• the sensor window is embedded in the elevator housing adjacent to the first side of the paddle loop;
• and
• the sensor window is inclined with respect to a direction of movement of the paddles, such that, in use, a clearance between an outer end of one of the paddles and the sensor window increases while the one of the paddles passes the sensor window.