Liquid injection molding apparatus

Abstract

A liquid injection molding apparatus is provided. The liquid injection molding apparatus comprises a mold assembly; a clamping unit; an injector including a barrel; a feed screw concentrically located in the barrel; and a motor having a drive shaft removably coupled to the feed screw via a bayonet connector.

1 .- 16 . (canceled) 
     
     
         17 . A liquid injection molding apparatus comprising:
 a mold assembly;   a clamping unit; and   an injector including
 a barrel, 
 a feed screw concentrically located in the barrel, and 
 a motor having a drive shaft removably coupled to the feed screw via a bayonet connector, the drive shaft including a hollow portion having a non-round cross-section. 
   
     
     
         18 . The liquid injection molding apparatus of  claim 17 , wherein the bayonet connector includes
 a receiver shaped for a snug fit and housed in the hollow portion of the drive shaft such that rotating the drive shaft about an axis of the drive shaft rotates the receiver, and   an insert including a first end removably coupled to and housed in the receiver, and a second end distal from the first end and coupled to the feed screw.   
     
     
         19 . The liquid injection molding apparatus of  claim 18 , wherein
 the receiver of the bayonet connector includes an axial opening, and a wall including an interior surface defining a cylindrical space connected to the axial opening, the wall including at least one lug projecting from the interior surface into the cylindrical space, distal from the axial opening, and   the insert of the bayonet connector includes an exterior surface, and at least one slot on the exterior surface at the first end, the at least one slot having an axial leg and a circumferential leg, the circumferential leg forming an acute angle with the axial leg at a junction, the axial leg including a third end distal from the junction, the third end including an axial opening to permit the at least one lug to enter the at least one slot when the third end engages the at least one lug, the circumferential leg including a fourth end distal from the junction such that rotating the receiver about an axis of the receiver in an angular direction to seat the at least one lug in the fourth end rotates the insert.   
     
     
         20 . The liquid injection molding apparatus according to  claim 19 , further comprising a collet, the drive shaft including an axial opening connected to the hollow portion, the collet threadably connected to the axial opening of the drive shaft to inhibit axial displacement of the receiver within the hollow portion thereby inhibiting the at least one lug from moving away from the fourth end. 
     
     
         21 . The liquid injection molding apparatus of  claim 20 , wherein the receiver of the bayonet connector includes another axial opening, distal from the axial opening of the receiver, connected to the cylindrical space, the first end of the insert extends through the receiver passing through both axial openings of the receiver. 
     
     
         22 . The liquid injection molding apparatus of  claim 21 , wherein the at least one lug includes more than one lug and the at least one slot includes more than one slot, each slot engaging a respective one of the more than one lug. 
     
     
         23 . The liquid injection molding apparatus of  claim 22 , wherein the insert of the bayonet connector is threadably connected to the feed screw. 
     
     
         24 . The liquid injection molding apparatus of  claim 19 , wherein the wall includes an exterior surface including four planar sides and four chamfers, each chamfer connecting two interconnected planar sides of the four planar sides, the at least one lug includes four lugs and the at least one slot includes four slots, each lug located at a respective chamfer. 
     
     
         25 . The liquid injection molding apparatus of  claim 18 , wherein
 the insert of the bayonet connector includes an exterior surface having at least one lug, at the first end, projecting radially away from the exterior surface, and   the receiver of the bayonet connector includes an axial opening, and a wall including an interior surface defining a cylindrical space connected to the axial opening, the interior surface including at least one slot having an axial leg and a circumferential leg, the circumferential leg forming an acute angle with the axial leg at a junction, the axial leg including a third end distal from the junction, the third end including an axial opening to permit the at least one lug to enter the at least one slot when the third end engages the at least one lug, the circumferential leg including a fourth end distal from the junction such that rotating the receiver about an axis of the receiver in an angular direction to seat the at least one lug in the fourth end rotates the insert.   
     
     
         26 . The liquid injection molding apparatus according to  claim 25 , further comprising a collet, the drive shaft including an axial opening connected to the hollow portion, the collet threadably connected to the axial opening of the drive shaft to inhibit axial displacement of the receiver within the hollow portion thereby inhibiting the at least one lug from moving away from the fourth end. 
     
     
         27 . The liquid injection molding apparatus of  claim 26 , wherein the receiver of the bayonet connector includes another axial opening, distal from the axial opening of the receiver, connected to the cylindrical space, the first end of the insert extends through the receiver passing through both axial openings of the receiver. 
     
     
         28 . The liquid injection molding apparatus of  claim 27 , wherein the at least one lug includes more than one lug and the at least one slot includes more than one slot, each slot engaging a respective one of the more than one lug. 
     
     
         29 . The liquid injection molding apparatus of  claim 28 , wherein the insert of the bayonet connector is threadably connected to the feed screw. 
     
     
         30 . The liquid injection molding apparatus of  claim 25 , wherein the receiver of the bayonet connector includes an exterior surface including four planar sides and four chamfers, each chamfer connecting two interconnected planar sides of the four planar sides, the at least one lug includes four lugs and the at least one slot includes four slots, each axial leg located at a respective chamfer. 
     
     
         31 . The liquid injection molding apparatus of  claim 30 , wherein the at least one slot extends from the interior surface to the exterior surface of the receiver. 
     
     
         32 . The liquid injection molding apparatus according to  claim 17 , wherein the non-round cross-section of the hollow portion of the drive shaft is a rounded rectangular cross-section. 
     
     
         33 . The liquid injection molding apparatus according to  claim 17 , wherein the non-round cross-section of the hollow portion of the drive shaft is a hexagonal cross-section. 
     
     
         34 . The liquid injection molding apparatus according to  claim 17 , wherein the non-round cross-section of the hollow portion of the drive shaft is an octagonal cross-section. 
     
     
         35 . The liquid injection molding apparatus according to  claim 17 , wherein the non-round cross-section of the hollow portion of the drive shaft is a D-shaped cross-section. 
     
     
         36 . The liquid injection molding apparatus according to  claim 17 , wherein the non-round cross-section of the hollow portion of the drive shaft is a square cross-section.