Pump with integral filter for a hot melt adhesive system

Abstract

An pump for use with a dispensing unit of a hot melt adhesive system includes a removable filter. The filter is coupled with a cartridge which is threaded into a chamber of the pump. The chamber is located between the inlet and outlet of the pump so that this portion of the flow path through the pump ensures passage of the hot melt adhesive through the removable filter. The pump provides convenient access to the filter for service and replacement.

1 . A pump for use in a dispensing unit of a hot melt adhesive system, the pump comprising: 
 a pump housing having an inlet, an outlet, and a chamber between said inlet and said outlet;    a piston slidably disposed within said housing such that motion of said piston draws the hot melt adhesive into said inlet and discharges the hot melt adhesive from said outlet; and    a filter removably positioned in said chamber between said inlet and said outlet to capture particulate material in the hot melt adhesive as the hot melt adhesive is pumped from said inlet to said outlet.    
   
   
       2 . The pump of  claim 1  wherein said filter is coupled to a cartridge that is removable from said pump housing.  
   
   
       3 . The pump of  claim 2  wherein said filter is removable from said cartridge.  
   
   
       4 . The pump of  claim 2  wherein said cartridge and said pump include respective threaded portions which are engageable with each other to allow coupling and decoupling of said cartridge and said pump.  
   
   
       5 . The pump of  claim 1  further comprising: 
 a pump manifold coupled in fluid communication with with said outlet of said pump housing and adapted to distribute the hot melt adhesive discharged from said outlet among a plurality of outlet ports.    
   
   
       6 . The pump of  claim 5  further comprising: 
 a tank having at least one side wall and a bottom collectively defining a tank interior for receiving the hot melt adhesive, said tank interior coupled in fluid communication with said inlet of said pump housing;    a tank heater associated with said tank for heating and melting the hot melt adhesive;    a manifold heater coupled thermally with said manifold; and    a controller adapted to control said manifold heater independent of said tank heater.    
   
   
       7 . The pump of  claim 5  further comprising: 
 a plurality of adhesive guns coupled in fluid communication with said plurality of outlet ports.    
   
   
       8 . The pump of  claim 7  further comprising: 
 a plurality of heated hoses coupling said plurality of adhesive guns in fluid communication with said plurality of outlet ports.    
   
   
       9 . The pump of  claim 7  further comprising: 
 a dispensing manifold coupling at least two of said plurality of adhesive guns in fluid communication with a corresponding one of said plurality of outlet ports.