Powder pump for conveying coating powder

Abstract

The invention relates to a powder pump ( 100; 100 ′) for conveying coating powder, the powder pump ( 100; 100 ′) having a powder chamber ( 10; 10 ′) with a casing tube ( 1; 1 ′) and a gas-permeable filter element ( 2; 2 ′) arranged inside the casing tube ( 1; 1 ′) a first pinch valve ( 3; 3 ′), connected to the intake-side end region of the powder chamber ( 10; 10 ′), and a second pinch valve ( 4; 4 ′), connected to the delivery-side end region of the powder chamber ( 10; 10 ′). In order to achieve the effect that the powder pump ( 100; 100 ′) can be maintained with relatively little effort, according to the invention a first connection element ( 6; 6 ′) is provided, connected to the first pinch valve ( 3; 3 ′) and fitted onto or inserted into the intake-side end region of the powder chamber ( 10; 10 ′). A second connection element ( 7; 7 ′) is also provided, connected to the second pinch valve ( 4; 4 ′) and fitted onto or inserted into the delivery-side end region of the powder chamber ( 10; 10 ′).

1 . A powder pump for conveying coating powder, the powder pump having the following:
 a powder chamber with a preferably cylindrical and in particular circular-cylindrical casing tube ( 1 ;  1 ′) and a gas-permeable filter element arranged inside the casing tube;   a first pinch valve, connected to the intake-side end region of the powder chamber; and   a second pinch valve, connected to the delivery-side end region of the powder chamber,   the powder pump having at least one connection for alternately creating a positive pressure and a negative pressure in the powder chamber,   wherein   a first connection element, which is connected to the first pinch valve and is fitted onto or inserted into the intake-side end region of the powder chamber;   a second connection element, which is connected to the second pinch valve and is fitted onto or inserted into the delivery-side end region of the powder chamber;   a mount for receiving the powder chamber with the connection elements fitted on or inserted in on both sides; and   an arresting mechanism for arresting the connection elements, fitted onto or inserted into the powder chamber on both sides, in relation to the mount when the powder chamber with the connection elements fitted on or inserted in on both sides has been received by the mount.   
     
     
         2 . The powder pump as claimed in  claim 1 ,
 the arresting mechanism having a first bolt, connected to the first connection element and protruding radially from the first connection element, and a second bolt, connected to the second connection element and protruding radially from the second connection element; and   the arresting mechanism also having a first longitudinal slit, provided in the mount and running perpendicularly to the longitudinal direction of the powder chamber, for receiving the first bolt, protruding radially from the first connection element, and a second longitudinal slit, provided in the mount and running perpendicularly to the longitudinal direction of the powder chamber, for receiving the second bolt, protruding radially from the second connection element.   
     
     
         3 . The powder pump as claimed in  claim 2 ,
 the end of the first longitudinal slit being adjoined at right angles by a short transverse slit; or   the end of the second longitudinal slit being adjoined at right angles by a short transverse slit.   
     
     
         4 . The powder pump as claimed in  claim 2 ,
 the arresting mechanism having first bolts, which are arranged diametrically in relation to each other, are each connected to the first connection element and each protrude radially from the first connection element, and the mount having two first longitudinal slits for each receiving one of the two first bolts.   
     
     
         5 . The powder pump as claimed in  claim 2 ,
 the arresting mechanism having two second bolts, which are arranged diametrically in relation to each other, are each connected to the second connection element and each protrude radially from the second connection element, and the mount having two second longitudinal slits for each receiving one of the two second bolts.   
     
     
         6 . The powder pump as claimed in  claim 1 ,
 the first connection element having a stub-like region, facing the powder chamber, and a tapering region, facing the first pinch valve and tapering conically in the direction of the first pinch valve,   the stub-like region of the first connection element being fitted onto or inserted into the intake-side end region of the powder chamber and the conically tapering region of the first connection element being connected to the first pinch valve.   
     
     
         7 . The powder pump as claimed in  claim 6 ,
 the stub-like region of the first connection element and the tapering region of the first connection element, tapering conically in the direction of the first pinch valve, being inserted in each other and releasably arrested in relation to each other, preferably with the aid of at least one countersunk screw.   
     
     
         8 . The powder pump as claimed in  claim 1 ,
 the second connection element having a stub-like region, facing the powder chamber, and a tapering region, facing the second pinch valve and tapering conically in the direction of the second pinch valve,   the stub-like region of the second connection element being fitted onto or inserted into the delivery-side end region of the powder chamber and the conically tapering region of the second connection element being connected to the second pinch valve.   
     
     
         9 . The powder pump as claimed in  claim 8 ,
 the stub-like region of the second connection element and the tapering region of the second connection element, tapering conically in the direction of the second pinch valve, being inserted in each other and releasably arrested in relation to each other, preferably with the aid of at least one countersunk screw.   
     
     
         10 . The powder pump as claimed in  claim 1 ,
 the first pinch valve and the second pinch valve each having the following:
 a pinch valve housing with an inlet-side flange and an outlet-side flange; and 
 an elastically deformable valve element in the form of a hose portion, 
   the valve element being arranged inside the pinch valve housing in such a way that the inlet of the pinch valve can be brought into fluidic connection with the outlet of the pinch valve by way of the valve element formed as a hose portion,   the pinch valve housing having at least one connection for feeding compressed air as and when required into the space formed between the inner wall of the pinch valve housing and the valve element arranged inside the pinch valve housing.   
     
     
         11 . The powder pump as claimed in  claim 10 ,
 the pinch valve housing having at least one connection for creating a negative pressure as and when required in the space formed between the inner wall of the pinch valve housing and the valve element arranged inside the pinch valve housing.   
     
     
         12 . The powder pump as claimed in  claim 10 ,
 the inlet-side flange and the outlet-side flange of the pinch valve being respectively releasably fastened to the pinch valve housing with the aid of screws.   
     
     
         13 . The powder pump as claimed in  claim 10 , the tapering region of the first connection element, tapering conically in the direction of the first pinch valve, being connected to the outlet of the first pinch valve by way of the outlet-side flange of the first pinch valve; and
 the tapering region of the second connection element, tapering conically in the direction of the second pinch valve, being connected to the inlet of the second pinch valve by way of the inlet-side flange of the second pinch valve.   
     
     
         14 . The powder pump as claimed in  claim 1 ,
 a control device also being provided, by way of which the first and second pinch valves are activated in such a way that, in an intake phase of the powder pump, the first pinch valve is open and the second pinch valve is closed, while at the same time a negative pressure is created in the powder chamber by way of the at least one connection, and, in a discharge phase of the powder pump, the first pinch valve is closed and the second pinch valve is open, while at the same time a positive pressure is created in the powder chamber by way of the at least one connection.   
     
     
         15 . An arrangement comprising a powder pump as claimed in  claim 1  and a further identical powder pump, the arrangement also having a first Y piece for connecting a powder line, in particular a powder hose, both to the inlet of the first pinch valve of the powder pump and to the inlet of the first pinch valve of the further identical powder pump, and a second Y piece also being provided, for connecting a powder line, in particular a powder hose, both to the outlet of the second pinch valve of the powder pump and to the outlet of the second pinch valve of the further identical powder pump. 
     
     
         16 . The arrangement—as claimed in  claim 15 ,
 the powder pump and the further powder pump being operated in phase opposition.