Turbine pump

A turbine pump for delivering fluidic coating material under pressure to coating equipment at one or more coating stations, comprising a plate having an annular ridge on a surface thereof forming a circular recess therein, said ridge having channels formed therein from an inner edge adjacent said recess to an outer edge thereof, said channels having a cross-sectional area which increases along their length from inner ends thereof at said inner edge to outer ends thereof at said outer edge;

• an impeller having outwardly extending blades positioned with at least a portion of said blades in said recess, said impeller being rotatable to move edges of said blades closely past said inner ends of said channels;
• a housing having walls forming a chamber therein and an opening thereto, positioned with portions of said walls around said opening on and around said ridge to enclose said impeller within said chamber, said housing having an inlet to said chamber for connection with a supply of coating material and said channels providing fluid outlets from said chamber for connection with the coating equipment;
• means for rotating said impeller within said housing, whereby with a constant speed of rotation of said impeller coating material supplied through said inlet is pumped from said outlets at an increased and substantially constant pressure despite variations in the flow rate of the material;
• and valve means for shunting a selected portion of the coating material around said outlets to control the pressure of the coating material delivered to the coating equipment, each said outlet having a base wall and side walls formed by said plate and a top wall provided by said wall margins of said housing, said base and top walls being substantially parallel, said side walls being substantially straight and parallel from said inner edge of said ridge to a first point along said channel, said side walls being substantially straight and diverging at a first angle from said first point to a second point along said channel, said side walls being substantially straight and diverging at a second and greater angle from said second point, one of said side walls being substantially straight from said second point to said outer edge of said ridge, the other of said side walls being substantially straight from said second point to a third point along said channel and being smoothly curved away from said one side wall from said third point to said outer edge of said ridge, said one side wall being tangent to said inner edge, said first angle being substantially 12.degree., said second angle being substantially 24.degree., and said other wall between said third point and said outer edge of said ridge being tangent both to said outer edge and to the portion thereof between said second and third points, said channels extending from said inner to outer ends thereof in directions generally along the direction of motion of said blade edges moving therepast, said one wall between said first and said second points extending 6.degree. out of the plane of said portion thereof between said inner edge and said first point in a direction away from said other wall, and said one wall between said second point and said outer edge extending 12.degree. out of the plane of said portion thereof between said inner edge and said first point in a direction away from said other wall, said impeller having a tubular center body portion about said axis and said blades extending outwardly therefrom, said means for rotating said impeller including a rotatable shaft extended into said housing and secured with said center body portion, said inlet to said housing being formed about said shaft and said shaft extending therethrough, said pump providing coating material from said outlets at a pressure determined by the speed of rotation of said impeller and the diameter thereof such that increasing speeds of rotation and increasing impeller diameters increase said pressure, said pressure being substantially constant for all coating material flow rates up to a design flow rate, said design flow rate being determined by the overall cross-sectional areas of said channels such that increasing said cross-sectional areas increases said design flow rate, and including a plurality of said pumps connected in series and having said impellers thereof rotated by said shaft, said housing of each said pump being connected with said outlets therefrom communicationg with said inlet to a succeeding housing, if any, said pumps forming a path therethrough for coating material from said inlet to the first pump housing to said outlets from the last pump housing, said plates having passages therethrough coaxial with said tubular center body portions of said impellers, said shaft extending through said plate passages and said tubular portions of said impellers and secured to each of said impellers for rotation thereof, each of said pumps increasing the pressure of coating material pumped therethrough by a predetermined amount, whereby coating material entering said inlet of said first pump housing exists said outlets from said last pump housing at an increased pressure which is the sum of said predetermined amounts.