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. Within a contrast media injector system, a method comprising the steps of:
positioning a syringe ram at a plurality of different locations;
acquiring at each location:
a) a first value of the syringe ram position from an encoder, and
b) a second value of a level of a reflected signal at an optical sensor, the optical sensor transmitting radiation to a reflective surface and determining an amount of reflective radiation that returns therefrom, the distance between the optical sensor and reflective surface being a function of the position of the syringe ram within the injector system;
associating the first and second values for each different location.
2. The method of claim 1 , further comprising the steps of:
detecting a level of radiation reflected from the reflected surface;
locating a second value substantially similar to the level of radiation and identifying its associated first value; and
determining a position of the syringe ram based on the first value.
3. A contrast media injector system comprising:
a syringe ram;
a drive mechanism coupled with the syringe ram and configured to move the syringe ram;
a reflective surface;
an optical sensor, wherein radiation is transmitted by the optical sensor towards the reflective surface, is reflected by the reflective surface, and is detected by the optical sensor to define a detected reflection, at least one of the optical sensor and the reflective surface being movable relative to the other as a function of movement of the syringe ram within the injector system, such that a distance traveled by said radiation between the reflective surface and the optical sensor is a measure of a position of the syringe ram within the injector system;
an encoder associated with the drive mechanism; and
a memory configured to store a plurality of syringe ram position data pairs, wherein each of the syringe ram position data pairs provides absolute position information for the syringe ram within the injector system, wherein each of the syringe ram position data pairs comprises a first value provided by the encoder and an associated second value corresponding to a magnitude of the detected reflection, wherein each second value is dependent upon a distance between the optical sensor and the reflective surface.
4. The system of claim 3 , wherein the optical sensor has a range of 1 cm to 30 cm.
5. The system of claim 3 , wherein each second value comprises a voltage level.
6. The system of claim 3 , wherein said memory comprises a look up table, that in turn comprises said plurality of syringe ram position data pairs.