Vacuum seed metering apparatus having housing openings

A seed metering apparatus for receiving seeds from a seed hopper and discharging the seeds at substantially regular intervals, said seed metering apparatus comprising:

• a vacuum source;
• a housing assembly including a first housing portion and a second housing portion to be releasably interconnected together, said first housing portion having an open sided cavity framed by a circumferential rim with at least part of said cavity defining a seed reservoir that receives seeds from said seed hopper, a drop chute formed integral with said first housing portion in separated relation from said seed reservoir and extending from a seed discharge area of said housing assembly to discharge seeds from said housing assembly, said second housing portion having an interior surface arranged in operable combination with the rim of said first housing portion to close said cavity, said second housing portion defining a vacuum chamber having a leading end and a trailing end and a vacuum exhaust port in communication with the vacuum chamber between the leading and trailing ends thereof and connectable to said vacuum source, at least one of said first and second housing portions having an opening arranged proximate to the seed discharge area of said housing assembly;
• and
• a disc metering member rotatably positioned within said rim of said first housing portion and having a series of openings arranged proximate to a periphery of said disc to receive seeds under the influence of pressure differentials acting thereon, said disc being rotatably mounted such that each opening in the disc is sequentially brought into communication with said seed reservoir and advances along a predetermined path of movement toward said drop chute whereat seeds are separated from the disc and pass into said drop chute for discharge from the seed metering apparatus, the opening arranged proximate to the seed discharge area promoting the release of seeds from the disc in the seed discharge area.