Automatic injection device

Abstract

An automatic injection device has piston holders holding cylinder pistons and plural systems of heads having a drive mechanism for moving the piston holders forward and backward so that the device can hold a plurality of syringes and operates injection or suction in each syringe independently. This device also has a mechanism for prohibiting the backward-moving of the piston holder of a second head when the piston holder of a first head is in a forward-moving state and the piston holder of the second head is in a stopped state. This structure effectively prevents liquid from being undesirably mixed and the injection amount thereof from becoming less accurate.

1 . An automatic injection device comprising piston holders holding cylinder pistons and plural systems of heads having a drive mechanism for moving the piston holders forward and backward, whereby the device can hold a plurality of syringes and operates injection or suction in each syringe independently, 
 said device comprising brake, wherein said brake is turned on when the piston holder of a first head is in a forward-moving state and the piston holder of a second head is in a stopped state, whereby backward-moving of the second head is prohibited, and wherein said brake is turned off when the second head is in a moving state.    
   
   
       2 . The automatic injection device according to  claim 1 , wherein said drive mechanism has a motor and mechanism for converting the rotation of the motor into a linear movement, and said brake prohibits the axis of rotation to rotate in the backward direction.  
   
   
       3 . The automatic injection device according to  claim 1 , wherein said drive mechanism has a motor and mechanism for converting the rotation of the motor into a linear movement, and said brake prohibits the linear movement in the backward direction.  
   
   
       4 . The automatic injection device according to  claim 1 , wherein said brake is a disc brake.  
   
   
       5 . The automatic injection device according to  claim 1 , wherein said device is a double head type with the number of systems of heads being two and holds two syringes.  
   
   
       6 . The automatic injection device according to  claim 1 , wherein said device holds a syringe for injecting a contrast medium and another syringe for injecting a physiological saline solution.  
   
   
       7 . The automatic injection device according to  claim 5 , wherein said device holds a syringe for injecting a contrast medium at the first head and a syringe for injecting a physiological saline solution at the second head.  
   
   
       8 . The automatic injection device according to  claim 5 , wherein the tips of the two syringes are connected to a three way-branched tube.  
   
   
       9 . The automatic injection device according to  claim 7 , wherein the tips of the two syringes are connected to a three way-branched tube.  
   
   
       10 . An automatic injection device comprising piston holders holding cylinder pistons and plural systems of heads having a drive mechanism for moving the piston holders forward and backward, whereby the device can hold a plurality of syringes and operates injection or suction in each syringe independently, 
 said device comprising a first head and a second head, wherein the force of a motor for driving the second head is transmitted to a piston holder of the second head via a worm gear while a worm gear is not provided in the transmission from a motor for driving a piston holder of the first head.    
   
   
       11 . The automatic injection device according to  claim 1 , wherein said device is a double head type with the number of systems of heads being two and holds two syringes.  
   
   
       12 . The automatic injection device according to  claim 1 , wherein said device holds a syringe for injecting a contrast medium and another syringe for injecting a physiological saline solution.  
   
   
       13 . The automatic injection device according to  claim 11 , wherein said device holds a syringe for injecting a contrast medium at the first head and a syringe for injecting a physiological saline solution at the second head.  
   
   
       14 . The automatic injection device according to  claim 11 , wherein the tips of the two syringes are connected to a three way-branched tube.  
   
   
       15 . The automatic injection device according to  claim 13 , wherein the tips of the two syringes are connected to a three way-branched tube.