Feeder Element for Metal Casting

Abstract

The present invention discloses a feeder element for use in metal casting, said feeder element comprising: (i) a first end for mounting on a mould pattern; (ii) an opposite second end for receiving a feeder sleeve,—and (iii) a bore between—the first and second ends defined by a stepped sidewall; said feeder element being compressible in use whereby to reduce the distance between the first and second ends, wherein the stepped sidewall has a first sidewall region defining the second end of the element and a mounting surface ( 54 ) for a feeder sleeve in use, said first sidewall region being inclined to the bore axis by less than 90° and a second sidewall region contiguous with the first sidewall region, said second sidewall region being parallel to or inclined to the bore axis at a different angle to the first sidewall region whereby to define a step in the sidewall. The feeder element offers improvements over the element disclosed in WO2005/051568.

1 . A feeder element for use in metal casting, said feeder element comprising:
 (iv) a first end for mounting on a mould pattern;   (v) an opposite second end for receiving a feeder sleeve; and   (vi) a bore between the first and second ends defined by a stepped sidewall;   said feeder element being compressible in use whereby to reduce the distance between the first and second ends, wherein the stepped sidewall has a first sidewall region defining the second end of the element and a mounting surface for a feeder sleeve in use, said first sidewall region being inclined to the bore axis by less than 90° and a second sidewall region contiguous with the first sidewall region, said second sidewall region being parallel to or inclined to the bore axis at a different angle to the first sidewall region whereby to define a step in the sidewall.   
   
   
       2 . The feeder element of  claim 1  comprising additional sidewall regions, whereby multiple steps in the sidewall are defined. 
   
   
       3 . The feeder element of  claim 2 , wherein at least one of the additional sidewall regions is inclined at a greater angle to the axis than the first sidewall region. 
   
   
       4 . The feeder element of any preceding claim, wherein the first sidewall region is inclined to the bore axis at an angle of between 5° and 85°. 
   
   
       5 . The feeder element of any preceding claim, wherein the first sidewall is inclined to the bore axis at an angle of between 30° and 70°. 
   
   
       6 . The feeder element of any preceding claim, wherein the initial crush strength is no more than 5000 N. 
   
   
       7 . The feeder element of any preceding claim, wherein the initial crush strength is at least 250 N. 
   
   
       8 . The feeder element of any preceding claim, wherein said compression in use is non-reversible. 
   
   
       9 . The feeder element of any preceding claim, wherein the stepped sidewall of the feeder element comprises a first series of sidewall regions in the form of rings interconnected and integrally formed with a second series of sidewall regions. 
   
   
       10 . The feeder element of  claim 9 , which is defined by the first sidewall region and one each of the first and second series of sidewall regions. 
   
   
       11 . The feeder element of  claim 9  or  10 , wherein the thickness of the sidewall regions is 0.2 to 1.5 mm. 
   
   
       12 . The feeder element as claimed in any one of  claims 9  to  11 , wherein said rings are circular. 
   
   
       13 . The feeder element of any one of  claims 9  to  12 , wherein said rings are planar. 
   
   
       14 . The feeder element of any one of  claims 9  to  13 , wherein the sidewall regions are of substantially uniform thickness, so that the diameter of the bore of the feeder element increases from the first end to the second end of the feeder element. 
   
   
       15 . The feeder element of any one of  claims 9  to  14 , wherein the second series of sidewall regions are annular. 
   
   
       16 . The feeder element of any one of  claims 9  to  15 , wherein the first end of the feeder element is defined by a sidewall region having a greater length than the other sidewall regions of the corresponding series. 
   
   
       17 . The feeder element of any one of  claims 9  to  16 , wherein the sidewall region defining the first end of the feeder element is inclined to the bore axis by an angle of 5 to 30°. 
   
   
       18 . The feeder element of any one of  claims 9  to  17 , wherein the thickness of the sidewall regions is from 4 to 24% of the distance between the inner and outer diameters of the first sidewall region(s). 
   
   
       19 . The feeder element of  claim 18 , wherein a free edge of the sidewall region defining the first end of the feeder element has an inwardly directed annular flange or bead. 
   
   
       20 . A feeder system for metal casting comprising a feeder element in accordance with any one of  claims 1  to  19  and a feeder sleeve secured thereto. 
   
   
       21 . A feeder system in accordance with  claim 20 , in which the feeder sleeve is secured to the feeder element by adhesive or by being a push fit with the feeder element or by moulding the sleeve around part of the feeder element. 
   
   
       22 . A feeder system in accordance with  claim 20  or  21 , wherein the base of the feeder sleeve is profiled at the same angle as the first sidewall region of the feeder element of any one of  claims 1  to  20 . 
   
   
       23 . A feeder system in accordance with any one of  claims 20  to  22 , wherein the sleeve strength is at least 5 kN and less than 20 kN.