Powerhead of a power injection system
View Patent ↗A contrast media injection system includes detects the absolute position of the syringe ram using a non-contact sensor. A series of magnets and Hall-Effect sensors may be used or an opto-reflective system. Illuminated knobs that are connected to the drive mechanism for the syringe ram rotate with the drive and provide visual feedback on operation through the illumination. Analog Hall-Effect sensors are used to determine the presence or absence of magnets that identify the type of faceplate being used. The faceplates include control electronics, connected to the powerhead through connectors, which may be interchangeably used by the two faceplates. The faceplate electronics include detectors for automatically detecting the capacity of pre-filled syringes. Additional features include using historical data to provide optimum pressure limit values during an injection protocol, a removable memory device for storing and transferring information such as injection protocols and injector statistics, and password protection of such protocols.
1. A contrast media injector system comprising:
a syringe ram engageable with a plunger of a syringe when mounted to said injector system;
a drive mechanism coupled with the syringe ram and configured to position the syringe ram at different locations;
a reflective surface; and
an optical sensor which transmits radiation towards the reflective surface and radiation is reflected therefrom back to the optical sensor, wherein a path of the radiation traveling between the reflective surface and the optical sensor is parallel to a dimension in which the syringe ram is moved by the drive mechanism,
only one of the optical sensor and the reflective surface being movable along with the syringe ram within the injector system such that the other of the optical sensor and the reflective surface does not move along with the syringe ram, wherein the reflective surface and the optical sensor are incorporated by the injector system such that movement of the syringe ram by the drive mechanism changes a spacing between the reflective surface and the optical sensor in a dimension that is parallel to the dimension in which the syringe ram is moved by the drive mechanism, and wherein the distance traveled by the radiation between the reflective surface and the optical sensor, in the dimension that is parallel to the dimension in which the syringe ram is moved by the drive mechanism, is a measure of an absolute position of the syringe ram at the different locations within the injector system.
2. The system of claim 1 , further comprising a computing circuit configured to estimate a distance from the optical sensor to the reflective surface, measured in the dimension that is parallel to the dimension in which the syringe ram is moved by the drive mechanism, based on the detected reflection.
3. The system of claim 1 , wherein the optical sensor has a range substantially between 1 cm and 30 cm.
4. The system of claim 1 , further comprising:
an encoder configured to determine a position of the drive mechanism;
a memory configured to store a respective position of the drive mechanism associated with a detected reflection of the optical sensor.
5. The system of claim 4 , further comprising:
a position detector configured to:
determine a detected reflection of the optical sensor;
search in the memory for the respective position associated with the detected reflection; and
determine the absolute position of the syringe ram based on the respective position.
6. The system of claim 1 , wherein the reflective surface provides a reflected signal to the optical sensor, wherein the reflected signal comprises the radiation, and wherein a strength of the reflected signal is indicative of the distance between the reflective surface and the optical sensor, measured in the dimension that is parallel to the dimension in which the syringe ram is moved by the drive mechanism.
7. The system of claim 1 , wherein the radiation comprises an optical signal, wherein an amount of light returned by the reflective surface to the optical sensor is proportional to the distance.