Supplemental Device for Attachment to an Injection Device

Abstract

A supplemental device for attachment to an injection device, the supplemental device having a housing containing at least two electromechanical switches each having an open state and a closed state and a protrusion associated with each switch configured to protrude from the housing so as to contact a rotatable surface of the injection device while the supplemental device is attached to the injection device; and a processor arrangement configured to detect a change in the state of each of the switches; and to determine a direction of rotation of the rotatable surface of the injection device from the detected state changes.

1 . A supplemental device for attachment to an injection device, the supplemental device comprising:
 a housing containing optical sensors arranged to detect optical features on a rotatable surface of the injection device while the supplemental device is attached to the injection device; and   a processor arrangement configured to:
 detect a change in state of each of the optical sensors; and 
 determine a direction of rotation of the rotatable surface of the injection device from the detected state changes. 
   
     
     
         2 . The supplemental device according to  claim 1 , wherein the optical sensors are arranged to detect optical features on a first portion of the rotatable surface that is closer to a dosage knob of the injection device than a second portion of the rotatable surface. 
     
     
         3 . The supplemental device according to  claim 2 , wherein the dosage knob is distal from a needle of the injection device. 
     
     
         4 . The supplemental device according to  claim 2 , wherein a portion of the rotatable surface extends axially beyond an axial end of a housing of the injection device when a dosage knob of the injection device is in a zero dose position. 
     
     
         5 . The supplemental device according to  claim 1 , wherein the rotatable surface is arranged to rotate relative to a housing of the injection device and extend axially beyond the housing of the injection device during dose dialing, and the optical sensors are arranged to detect optical features on the rotatable surface of the injection device during dose dialing. 
     
     
         6 . The supplemental device according to  claim 1 , wherein the optical sensors are arranged to face the rotatable surface at different relative angular positions when the supplemental device is attached to the injection device. 
     
     
         7 . The supplemental device according to  claim 1 , wherein the processor arrangement is configured to determine the direction of rotation of the rotatable surface based on a relative order in which the states of the optical sensors change during rotation of the rotatable surface. 
     
     
         8 . The supplemental device according to  claim 1 , wherein the processor arrangement is configured to:
 determine a state of each of the optical sensors before rotation of the rotatable surface;   determine the state of each of the optical sensors after rotation of the rotatable surface; and   determine the direction of rotation of the rotatable surface based on the determined states of each of the optical sensors before rotation of the rotatable surface and after rotation of the rotatable surface.   
     
     
         9 . The supplemental device according to  claim 1 , wherein the optical features comprise black and white regions detectable by the optical sensors, wherein each optical sensor is in a first state when a black region of the rotatable surface is detected and a second state when a white region or the rotatable surface is detected. 
     
     
         10 . The supplemental device according to  claim 1 , wherein the supplemental device comprises one or more light emitting diodes arranged to illuminate the optical features. 
     
     
         11 . The supplemental device according to  claim 1 , wherein each of the optical sensors comprises a camera. 
     
     
         12 . A supplemental device for attachment to an injection device, the supplemental device comprising:
 a housing containing sensors arranged to detect conductive and non-conductive features on a rotatable surface of the injection device while the supplemental device is attached to the injection device; and   a processor arrangement configured to:
 detect a change in state of each of the sensors; and 
 determine a direction of rotation of the rotatable surface of the injection device from the detected state changes. 
   
     
     
         13 . The supplemental device according to  claim 12 , wherein the sensors are arranged to protrude from the housing of the supplemental device. 
     
     
         14 . The supplemental device according to  claim 12 , wherein the processor arrangement is configured to determine the direction of rotation of the rotatable surface based on a relative order in which the states of the sensors change during rotation of the rotatable surface. 
     
     
         15 . The supplemental device according to  claim 12 , wherein the processor arrangement is configured to: determine a state of each of the sensors before rotation of the rotatable surface;
 determine the state of each of the sensors after rotation of the rotatable surface; and   determine the direction of rotation of the rotatable surface based on the determined states of each of the sensors before rotation of the rotatable surface and after rotation of the rotatable surface.   
     
     
         16 . The supplemental device according to  claim 12 , wherein the sensors are magnetic sensors. 
     
     
         17 . The supplemental device according to  claim 12 , wherein the sensors are resistive sensors. 
     
     
         18 . The supplemental device according to  claim 12 , wherein the sensors are capacitive sensors. 
     
     
         19 . The supplemental device according to  claim 12 , wherein the sensors comprise contacts configured to engage with the conductive and non-conductive features. 
     
     
         20 . An injection device comprising:
 a housing containing sensors arranged to detect (i) optical features or (ii) conductive and non-conductive features on a rotatable surface of the injection device; and   a processor arrangement configured to:
 detect a change in state of each of the sensors; and 
 determine a direction of rotation of the rotatable surface of the injection device from the detected state changes.