Monitoring injector operation

Abstract

Embodiments of the present invention monitor resistance to the movement of the ram and detect one or more injector operation conditions based on that resistance. Some embodiments automatically detect whether a syringe is present in each syringe chamber of an injector based on ram movement resistance so that subsequent steps in the inject process can be automatically initiated or delayed based on the presence or absence of the syringe(s). Other injector operation conditions that can be detected include the injector's syringe sleeve being misaligned for operation, the syringe's wiper being misaligned within the syringe barrel, an occlusion within the syringe, overpressure during injection, and so on. A common way to measure resistance of the ram's movement is how much current is required by the motor driving the ram.

1 . A computer-readable medium programmed with instructions for detecting a condition of an injector's operation, the medium comprising instructions for causing a programmable processor to:
 (a) receive a first set of ram motion information regarding movement of a first ram of the injector in a first syringe chamber of the injector;   (b) receive a first set of resistance information indicating how much the movement of the first ram was resisted; and   (c) determine whether a first injector operation condition is present based on the first set of ram motion information and the first set of resistance information.   
     
     
         2 . The medium of  claim 1 , wherein the first injector operation condition comprises a first syringe being present in the first syringe chamber. 
     
     
         3 . The medium of  claim 2 , wherein the instructions for causing the programmable processor to determine whether the first syringe is present in the first syringe chamber comprise instructions for causing the programmable processor to conclude that (i) the first syringe is present in the first syringe chamber if the first set of resistance information indicates that the movement of the first ram was resisted by a predetermined amount of pressure or more or (ii) no syringe is present in the first syringe chamber if the first set of resistance information indicates that the movement of the first ram was resisted by less than the predetermined amount of pressure. 
     
     
         4 . The medium of  claim 2 , further comprising instructions for causing the programmable processor to (d) begin a syringe-fill process if it is determined that the first syringe is present in the first syringe chamber. 
     
     
         5 . The medium of  claim 2 , further comprising:
 (d) receive a second set of ram motion information regarding movement of a second ram of the injector in a second syringe chamber of the injector;   (e) receive a second set of resistance information indicating how much the movement of the second ram was resisted; and   (f) determine whether a second syringe is present in the second syringe chamber based on the second set of ram motion information and the second set of resistance information.   
     
     
         6 . The medium of  claim 1 , wherein the first set of resistance information includes how much current was required by a motor of the injector to drive the first ram in the movement of the first ram. 
     
     
         7 . The medium of  claim 1 , further comprising instructions for causing the programmable processor to (d) determine whether a second injector operation condition is present based on the first set of ram motion information and the first set of resistance information. 
     
     
         8 . The medium of  claim 1 , wherein the first injector operation condition is selected from a group consisting of: a first syringe being present in the first syringe chamber, a syringe sleeve of the first syringe chamber being not closed properly for operation, a wiper of the first syringe being misaligned with a barrel of the first syringe, an occlusion within the syringe, and overpressure during injection. 
     
     
         9 . A method comprising:
 (a) providing an injector that includes (i) a first syringe chamber and (ii) a first ram;   (b) causing the first ram to move in an advancing direction and/or a retracting direction in the first syringe chamber;   (c) measuring how much the movement of the first ram is resisted; and   (d) concluding that a first injector operation condition is present based on one or more characteristics of the movement of the first ram and on how much the movement of the first ram is resisted.   
     
     
         10 . The method of  claim 9 , wherein
 the first injector operation condition is that a first syringe is present in the first syringe chamber,   the one or more characteristics of the movement of the first ram includes that the first ram has moved a first distance, and   how much the movement of the first ram is resisted includes that the movement of the first ram is resisted by a first predetermined amount of pressure or more.   
     
     
         11 . The method of  claim 10 , further comprising (e) automatically beginning a syringe-fill process if it is concluded that the first syringe is present in the first syringe chamber. 
     
     
         12 . The method of  claim 10 , wherein:
 the injector further includes (iii) a second syringe chamber and (iv) a second ram, and the method further comprises:
 (e) causing the second ram to move a second distance in the second syringe chamber; 
 (f) measuring how much the movement of the second ram is resisted; and 
 (g) concluding that (i) a second syringe is present in the second syringe chamber if the movement of the second ram is resisted by a second predetermined amount of pressure or more or (ii) no syringe is present in the second syringe chamber if the movement of the second ram is resisted by less than the second predetermined amount of pressure. 
   
     
     
         13 . The method of  claim 9 , wherein measuring how much the movement of the first ram is resisted includes measuring current supplied to a motor that drives the movement of the first ram. 
     
     
         14 . The method of  claim 9 , wherein the first injector operation condition is selected from a group consisting of: a first syringe being present in the first syringe chamber, a syringe sleeve of the first syringe chamber being not closed properly for operation, a wiper of the first syringe being misaligned with a barrel of the first syringe, an occlusion within the syringe, and overpressure during injection. 
     
     
         15 . An injection system comprising:
 (a) an injector that includes a first syringe chamber and a first ram; and   (b) an injector control system that includes a processor and a storage device, wherein the storage device comprises:
 (i) a ram motion data module that, when executed by the processor, causes the processor to collect a first set of ram motion information regarding movement of the first ram in the first syringe chamber; 
 (ii) a resistance detection module that, when executed by the processor, causes the processor to collect a first set of resistance information indicating how much the movement of the first ram is resisted; and 
 (iii) an operation condition detection module that, when executed by the processor, causes the processor to (A) receive the first set of ram motion information from the ram motion data module, (B) receive the first set of resistance information from the resistance detection module, and (C) determine whether a first injector operation condition is present based on the first set of ram advancement information and the first set of resistance information. 
   
     
     
         16 . The injection system of  claim 15 , wherein the operation condition detection module, when executed by the processor, causes the processor to determine whether a first syringe is present in the first syringe chamber by concluding that:
 a first syringe is present in the first syringe chamber if the first set of resistance information indicates that the movement of the first ram is resisted by a predetermined amount of pressure or more or   no syringe is present in the first syringe chamber if the first set of resistance information indicates that the movement of the first ram is resisted by less than the predetermined amount of pressure.   
     
     
         17 . The injection system of  claim 16 , wherein the storage device further comprises (iv) an inject process module that, when executed by the processor, causes the processor to automatically begin a syringe-fill process if it is determined that the first syringe is present in the first syringe chamber. 
     
     
         18 . The injection system of  claim 15 , wherein:
 the injector further includes a motor configured to drive the first ram, and   the first set of resistance information includes how much current is required by the motor to drive the first ram.   
     
     
         19 . The injection system of  claim 15 , wherein the first injector operation condition is selected from a group consisting of: a first syringe being present in the first syringe chamber, a syringe sleeve of the first syringe chamber being not closed properly for operation, a wiper of the first syringe being misaligned with a barrel of the first syringe, an occlusion within the syringe, and overpressure during injection. 
     
     
         20 . The injection system of  claim 15 , wherein the first set of ram motion information includes one or more of:
 a location of the first ram relative to a reference point,   a duration of time that the first ram has been moving, and   a rate at which the first ram is moving or accelerating.