Patent Publication Number: US-2022233781-A1

Title: Injection device with dosage monitoring

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to hypodermic needles and syringes, and particularly to syringes for measuring and monitoring an injectant dosage. 
     BACKGROUND OF THE INVENTION 
     Injection devices are widely used for administering injections, such as for injecting a medication or drug into the body of a patient. One of the most common types of injection devices is a syringe. A syringe generally consists of a plunger, tightly fitted within a cylindrical barrel or chamber, and a hypodermic needle fitted at the distal end of the syringe. The plunger is linearly advanceable within the syringe chamber, which contains an injectant substance. The injection is implemented by piercing the skin with the needle at a selected body region and then manually depressing the plunger, which forces the injectant substance to be ejected through the needle aperture. The syringe or the needle is typically intended for single use (disposable), but is sometimes designated for repeated usage. Syringes are frequently utilized in clinical medicine to administer drugs or medications, to deliver fluids into the bloodstream for infusions or intravenous therapy, to apply compounds (e.g., such as adhesives or lubricants), or to extract and measure fluids (e.g., blood samples). Syringes and injection devices come in a wide variety of different types and categories, including safety syringes, injection pens, auto-injector devices, and insulin pumps. For example, a safety syringe may incorporate a retraction mechanism to retract the needle inside the syringe chamber after completion of the injection, in order to preclude contamination and prevent potential injury from the exposed needle. 
     Certain medical treatments involving syringe injections must be performed by a clinician or certified medical staff and requires the patient to be hospitalized. Such hospitalizations can be expensive and time-consuming. A patient may alternatively visit an outpatient clinic to receive the injection, which can also be troublesome and inconvenient. Self-administering an injection can be difficult and is generally considered unreliable, and can result in improper injections and medical complications. For example, it may be especially difficult to measure and monitor a precise dosage of the medication or substance that needs to be injected. When conducting medical research involving periodic injections of a subject patient, self-administered injections is considered to compromise the veracity of the usage. 
     Various devices and methods for measuring injected dosages are known in the art. Many of these devices have limitations, such as lack of reliability, complicated designs, and costly manufacturing expenses. 
     U.S. Pat. No. 6,352,523 to Brown et al., entitled: “Capacitance-based dose measurements in syringes”, is directed to an apparatus and method for capacitively measuring insulin quantities in a syringe in an integrated insulin dose recorder/blood glucose meter. The syringe is placed in a holder before and after the administration of the dose. Capacitor electrodes may be situated within the syringe and/or outside the syringe in various geometries. Liquid quantities in the syringe are determined by comparing capacitive response patterns of the syringe with calibration data stored in the device. Dose histories are downloaded to a patient computer for transfer to a clinician&#39;s computer. 
     U.S. Pat. No. 6,743,202 to Hirschman et al., entitled: “Encoding of syringe information”, is directed to an apparatus and method for injecting fluid into a patient in which syringe information relevant to the injection procedure is encoded and shared with an injector. The encoded syringe information is readable by a detection circuit in the injector, which may include electrically conductive contact readout members. The encoded syringe information is stored by a storage system, which may include electrically conductive code contact members. The syringe information may be conveyed to the detector when contact is made between the storage system and the detector. 
     European Patent No. 1,827,537 to Enggaard et al., entitled: “Medication delivery system with a detector for providing a signal indicative of an amount of an ejected dose of drug”, is directed to a medication delivery system for identified the amount of an ejected dose. The system includes a movable part adapted to move relative to a stationary part, at least two conductors arranged such that an electrical characteristic is defined by the mutual position or relative movement of the two parts, and a detector for detecting a change of the electrical characteristic. The parts are stationary relative to each other during the does setting, and moved relative to each other during the dose ejections, such that the detector provides a signal indicative of the actual amount of the ejected dose. 
     U.S. Pat. No. 9,586,009 to Butler et al., entitled: “Drug delivery device”, is directed to a pen-type injection device that provides injection of medicinal products from a multi-dose cartridge where a user may set the dose. The device includes a cylindrical member rotatably supported inside a housing. The outer surface of the cylindrical member is provided with at least first and second tracks together forming an encoder. Each track includes conductive segments and non-conductive segments. First and second groups of contacts are configured to engage the first and second tracks respectively at predetermined intervals along the length of the track. 
     The aforementioned publications generally relate to electromechanical devices which generate an electrical signal that reflects the dosage of injected material. Other approaches for measuring injectant dosages are also known in the art. For example, U.S. Pat. No. 9,255,830 to Whalley et al., entitled: “Dose measurement system and method”, discloses an optical-based technique for measuring the dose remaining in a drug delivery device. A plurality of light sources is disposed in an apparatus and configured to emit electromagnetic radiation toward a container. A plurality of sensors optically couplable to the light sources are located in the apparatus and configured to detect the emitted electromagnetic radiation. A processing unit is configured to receive data representing the detected electromagnetic information from the sensors and convert the received data into a representative signature. The signature may be representative of a drug volume in the drug delivery device. The processing unit may include a memory, such as an RFID chip, configured to store information, such as the remaining dose. 
     Another relevant publication is U.S. Patent Application No. 2019/0054251 to Pieronek et al., entitled: “Medicine delivery device”, directed to techniques for sensing a dosage setting at a medicine delivery device. The device includes a container configured to store medicine, and a movable component configured to set a dosage of medicine to be dispensed. A dispensing mechanism is configured to deliver the dosage of the medicine, and one or more sensors are configured to generate data samples related to a movement of the movable component. A processor determined based on the data samples a direction and a distance of at least one movement component, determines based on the direction and distance a dosage of medicine set by the movable component, compares the dosage against a preset threshold, and performs one or more actions related to the delivery of the dosage based on the comparison. Information may also be communicated remotely from the medicine delivery device, such as to a patient&#39;s mobile device. 
     SUMMARY OF THE INVENTION 
     In accordance with one aspect of the present invention, there is thus provided an injection device. The device has a distal end and a proximal end. The device includes a syringe, which includes a syringe chamber containing an injectant substance. The device further includes a plunger, which includes a plunger rod axially displaceable within the syringe chamber. The device further includes at least one element, configured to undergo a corresponding element motion linked to a distal displacement of the plunger rod. The device further includes an electronics unit, including at least one sensor, configured to obtain detection readings relating to the corresponding element motion of the element. An injection is performed by depressing the plunger rod in a distal direction, compelling a corresponding element motion detected by the sensor, and compelling the injectant substance to be injected through a distal end of the syringe chamber. The detection readings relating to the corresponding element motion of the element is processed to determine injection information including at least the volume of injectant substance injected. The element may include a rotor, which includes a rotor rod, disposed concentrically within the plunger rod, and a rotor head, at a proximal end of the rotor rod. The rotor head is configured to rotate in accordance with a distal advancement of the plunger rod, such that the corresponding element motion is a rotational motion of the rotor head, where the sensor is configured to detect the rotational motion of the rotor head. The rotor rod may further include a helical screw thread, and the injection device may further include at least one guiding pin, configured to engage the screw thread, so as to turn the rotor rod, producing the rotational motion of the rotor head. The guiding pin may be disposed on a ring element, at least partially encircling the plunger rod, the guiding pin extending radially inward from the ring element, where the guiding pin engages the screw thread through a plunger rod slot, extending axially along the plunger rod, such that the guiding pin is restricted to linear axial motion with respect to the plunger rod by the plunger rod slot, preventing rotation of the ring element with respect to the plunger rod. The rotor head may include a plurality of rotor head apertures, where the sensor is configured to detect a sequential passage of the rotor head apertures during the rotational motion of the rotor head. The element may include a rotor, which includes a rotor head, at least partially encircling the plunger rod, where the rotor head is configured to rotate in accordance with a distal advancement of the plunger rod, such that the corresponding element motion is a rotational motion of the rotor head, where the sensor is configured to detect the rotational motion of the rotor head during the distal advancement of the plunger rod. The plunger rod may include a helical screw thread, where the rotor head further includes at least one guiding pin, extending radially inward from an inner wall of the rotor head, the guiding pin configured to engage the screw thread, so as to turn the rotor, producing the rotational motion of the rotor head. The injection device may further include a gripping unit, which includes a gripping unit opening, such that the plunger rod extends through the gripping unit opening, shaped with at least one edge aligned with an edge of the plunger rod, so as to prevent a rotation of the plunger rod relative to the gripping unit. The rotor head may include a plurality of rotor head apertures, where the sensor is configured to detect a sequential passage of the rotor head apertures during the rotational motion of the rotor head. The element may include a plurality of teeth, extending axially along a portion of the plunger rod, each tooth of the teeth including a respective tooth protrusion, protruding radially outwards from the plunger rod, and a respective tooth indentation, protruding radially inwards from the plunger rod, where the corresponding element motion is an axial motion of the teeth, and where the sensor is configured to detect the sequential passage of the teeth during the distal advancement of the plunger rod. The injection device may further include a gripping unit, comprising a gripping unit opening, such that the plunger rod extends through the gripping unit opening, shaped with at least one edge aligned with an edge of the plunger rod, so as to prevent a rotation of the plunger rod relative to the gripping unit. The element may include a rack, positioned within the plunger rod, the rack including a plurality of teeth, extending axially along a portion of the rack, each tooth of the teeth comprising a respective tooth protrusion, projecting radially through an axial slot of the plunger rod when the rack is positioned within the plunger rod, where the corresponding element motion is a sequential axial motion of the rack, and where the sensor is configured to detect the sequential axial motion of the rack during the distal advancement of the plunger rod. The injection device may further include a substantially flexible ring, at least partially encircling the plunger rod, the ring including at least one ring tooth extending radially inward from the ring, the ring tooth configured to engage with a rack tooth of the rack through the axial slot of the plunger rod, such that the ring is prevented from rotation with respect to the plunger rod. The ring may include at least one flexible portion, configured to selectively deform radially, where during the distal advancement of the plunger rod, the rack is restricted from distal displacement by the ring tooth, resulting in a proximal counterforce applied by the rack, initiating a cyclical activation of the sensor and a cyclical radial expansion of the ring, allowing the distal advancement of a respective rack tooth through the ring, and detection of the rack tooth distal advancement by the sensor for each cycle. The electronics unit may further include a transmitting antenna, configured to transmit the detection readings to a remote location. The electronics unit may further include an indicator, configured to provide an indication of at least one injection state relating to the injection. 
     In accordance with another aspect of the present invention, there is thus provided a method for monitoring injection information relating to an injection. The method includes the procedure of providing an injection device, the device having a distal end and a proximal end, the device including a syringe, which includes a syringe chamber containing an injectant substance, the device further including a plunger, which includes a plunger rod axially displaceable within the syringe chamber, the device further including at least one element, configured to undergo a corresponding element motion linked to a distal displacement of the plunger rod, the device further including an electronics unit, including at least one sensor, configured to obtain detection readings relating to the corresponding element motion of the element. The method further includes the procedure of performing an injection by depressing the plunger rod in a distal direction, compelling a corresponding element motion detected by the sensor, and compelling the injectant substance to be injected through a distal end of the syringe chamber. The method further includes the procedure of processing the detection readings relating to the corresponding element motion of the element to determine injection information including at least the volume of injectant substance injected. The element may include a rotor, which includes a rotor rod, disposed concentrically within the plunger rod, and a rotor head, at a proximal end of the rotor rod. The rotor head is configured to rotate in accordance with a distal advancement of the plunger rod, such that the corresponding element motion is a rotational motion of the rotor head, where the sensor is configured to detect the rotational motion of the rotor head. The rotor rod may further include a helical screw thread, and the injection device may further include at least one guiding pin, configured to engage the screw thread, so as to turn the rotor rod, producing the rotational motion of the rotor head. The guiding pin may be disposed on a ring element, at least partially encircling the plunger rod, the guiding pin extending radially inward from the ring element, where the guiding pin engages the screw thread through a plunger rod slot, extending axially along the plunger rod, such that the guiding pin is restricted to linear axial motion with respect to the plunger rod by the plunger rod slot, preventing rotation of the ring element with respect to the plunger rod. The rotor head may include a plurality of rotor head apertures, where the sensor is configured to detect a sequential passage of the rotor head apertures during the rotational motion of the rotor head. The element may include a rotor, which includes a rotor head, at least partially encircling the plunger rod, where the rotor head is configured to rotate in accordance with a distal advancement of the plunger rod, such that the corresponding element motion is a rotational motion of the rotor head, where the sensor is configured to detect the rotational motion of the rotor head during the distal advancement of the plunger rod. The plunger rod may include a helical screw thread, where the rotor head further includes at least one guiding pin, extending radially inward from an inner wall of the rotor head, the guiding pin configured to engage the screw thread, so as to turn the rotor, producing the rotational motion of the rotor head. The injection device may further include a gripping unit, which includes a gripping unit opening, such that the plunger rod extends through the gripping unit opening, shaped with at least one edge aligned with an edge of the plunger rod, so as to prevent a rotation of the plunger rod relative to the gripping unit. The rotor head may include a plurality of rotor head apertures, where the sensor is configured to detect a sequential passage of the rotor head apertures during the rotational motion of the rotor head. The element may include a plurality of teeth, extending axially along a portion of the plunger rod, each tooth of the teeth including a respective tooth protrusion, protruding radially outwards from the plunger rod, and a respective tooth indentation, protruding radially inwards from the plunger rod, where the corresponding element motion is an axial motion of the teeth, and where the sensor is configured to detect the sequential passage of the teeth during the distal advancement of the plunger rod. The injection device may further include a gripping unit, comprising a gripping unit opening, such that the plunger rod extends through the gripping unit opening, shaped with at least one edge aligned with an edge of the plunger rod, so as to prevent a rotation of the plunger rod relative to the gripping unit. The element may include a rack, positioned within the plunger rod, the rack including a plurality of teeth, extending axially along a portion of the rack, each tooth of the teeth comprising a respective tooth protrusion, projecting radially through an axial slot of the plunger rod when the rack is positioned within the plunger rod, where the corresponding element motion is a sequential axial motion of the rack, and where the sensor is configured to detect the sequential axial motion of the rack during the distal advancement of the plunger rod. The injection device may further include a substantially flexible ring, at least partially encircling the plunger rod, the ring including at least one ring tooth extending radially inward from the ring, the ring tooth configured to engage with a rack tooth of the rack through the axial slot of the plunger rod, such that the ring is prevented from rotation with respect to the plunger rod. The ring may include at least one flexible portion, configured to selectively deform radially, where during the distal advancement of the plunger rod, the rack is restricted from distal displacement by the ring tooth, resulting in a proximal counterforce applied by the rack, initiating a cyclical activation of the sensor and a cyclical radial expansion of the ring, allowing the distal advancement of a respective rack tooth through the ring, and detection of the rack tooth distal advancement by the sensor for each cycle. The method may further include the procedure of transmitting the detection readings to a remote location with a transmitting antenna of the electronics unit. The method may further include the procedure of providing an indication of at least one injection state relating to the injection with an indicator of the electronics unit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be understood and appreciated more fully from the following detailed description taken in conjunction with the drawings in which: 
         FIG. 1  is a perspective view illustration of an injection device in an assembled configuration, constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 2  is an exploded perspective view illustration of the injection device of  FIG. 1 , constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 3  is a perspective view illustration of the gripping unit of the injection device of  FIG. 1 , constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 4  is a perspective view illustration of the ring element of the injection device of  FIG. 1 , constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 5A  is a perspective view illustration of the plunger of the injection device of  FIG. 1 , constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 5B  is a lateral sectional view illustration of the plunger of  FIG. 5A ; 
         FIG. 5C  is a rotated lateral sectional view illustration of the plunger view of  FIG. 5B ; 
         FIG. 5D  is a proximal view illustration of the plunger of  FIG. 5A ; 
         FIG. 6A  is a perspective view illustration of the rotor of the injection device of  FIG. 1 , constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 6B  is a lateral view illustration of the rotor of  FIG. 6A ; 
         FIG. 7A  is a perspective view illustration of the cap of the injection device of  FIG. 1 , depicting a proximal surface thereof, constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 7B  is a perspective view illustration of the cap of  FIG. 7A , depicting a distal surface thereof; 
         FIG. 8A  is a perspective view illustration of the electrical board of the injection device of  FIG. 1 , depicting a distal surface thereof, constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 8B  is a perspective view illustration of the electrical board of  FIG. 8A , depicting a proximal surface thereof; 
         FIG. 9A  is an orthographic view illustration of the injection device of  FIG. 1  in an initial operational state, constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 9B  is a rotated orthographic view illustration of the injection device of  FIG. 9A ; 
         FIG. 9C  is a sectional view illustration of the injection device of  FIG. 9B ; 
         FIG. 10  is a perspective view illustration of the rotor and ring element of the injection device of  FIG. 1 , when in an initial operational state, constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 11  is an orthographic view illustration of the injection device of  FIG. 1 ) prior to the needle insertion with the rigid needle shield (RNS) removed, constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 12A  is an orthographic view illustration of the injection device of  FIG. 1  at a later operational state with the plunger rod fully depressed, constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 12B  is an orthographic view illustration of the injection device of  FIG. 12A  at a later operational state with the plunger rod fully depressed; 
         FIG. 12C  is a sectional view illustration of the injection device of  FIG. 12B ; 
         FIG. 13  is a perspective view illustration of an injection device in an assembled configuration, constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 14  is an exploded perspective view illustration of the injection device of  FIG. 13 , constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 15A  is a perspective view illustration of the gripping unit of the injection device of  FIG. 13 , constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 15B  is a rotated view illustration of the gripping unit view of  FIG. 15A ; 
         FIG. 16  is a perspective view illustration of the ring element of the injection device of  FIG. 13 , constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 17A  is a perspective view illustration of the cap of the injection device of  FIG. 13 , depicting a distal surface thereof, constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 17B  is a perspective view illustration of the cap of  FIG. 17A , depicting a proximal surface thereof; 
         FIG. 18A  is a perspective view illustration of the electrical board of the injection device of  FIG. 13 , depicting a distal surface thereof, constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 18B  is a perspective view illustration of the electrical board of  FIG. 18A , depicted a proximal surface thereof; 
         FIG. 19  is a perspective view illustration of the plunger of the injection device of  FIG. 13 , constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 20  is a perspective view illustration of the plunger with ring element of the injection device of  FIG. 13 , constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 21A  is an orthographic distal view illustration of the rotor and the sensor of the injection device of  FIG. 13 , constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 21B  is an orthographic lateral view illustration of the rotor and the sensor of  FIG. 21A ; 
         FIG. 21C  is an orthographic proximal view illustration of the rotor and the sensor of  FIG. 21A ; 
         FIG. 22A  is an orthographic view illustration of the injection device of  FIG. 13 , when in an initial operational state, constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 22B  is a rotated orthographic view illustration of the injection device of  FIG. 22A ; 
         FIG. 22C  is a sectional orthographic view illustration of the injection device of  FIG. 22B ; 
         FIG. 23  is an orthographic view illustration of the injection device of  FIG. 13 , prior to the needle insertion with the rigid needle shield (RNS) removed, constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 24A  is an orthographic view illustration of the injection device of  FIG. 13  at a later operational state with the plunger rod fully depressed, constructed and operative in accordance with a second embodiment of the present invention; 
         FIG. 24B  is a sectional orthographic view illustration of the injection device of  FIG. 24A ; 
         FIG. 25  is a perspective view illustration of an injection device in an assembled configuration, constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 26  is an exploded perspective view illustration of the injection device of  FIG. 25 , constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 27A  is a perspective proximal view illustration of the gripping unit of the injection device of  FIG. 25 , constructed and operative in accordance with a first embodiment of the present invention; 
         FIG. 27B  is a perspective distal view illustration of the gripping unit of  FIG. 27A ; 
         FIG. 28A  is a perspective view illustration of the cap of the injection device of  FIG. 25 , depicting a proximal surface thereof, constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 28B  is a perspective view illustration of the cap of  FIG. 28A , depicting a distal surface thereof; 
         FIG. 29A  is a perspective view illustration of the electrical board of the injection device of  FIG. 25 , depicting a proximal surface thereof, constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 29B  is a perspective view illustration of the electrical board of  FIG. 29A , depicting a distal surface thereof; 
         FIG. 30  is a perspective view illustration of the plunger of the injection device of  FIG. 25 , constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 31A  is an orthographic view illustration of the plunger and the sensor of the injection device of  FIG. 25 , constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 31B  is an orthographic view illustration of the plunger and sensor view of  FIG. 31A ; 
         FIG. 32A  is an orthographic view illustration of the injection device of  FIG. 25 , when in an initial operational state, constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 32B  is a sectional view illustration of the injection device of  FIG. 32A ; 
         FIG. 33  is an orthographic view illustration of the injection device of  FIG. 25 , prior to the needle insertion with the rigid needle shield (RNS) removed, constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 34A  is an orthographic view illustration of the injection device of  FIG. 25  at a later operational state with the plunger rod fully depressed, constructed and operative in accordance with a third embodiment of the present invention; 
         FIG. 34B  is a sectional orthographic view illustration of the injection device of  FIG. 34A ; 
         FIG. 35  is a perspective view illustration of an injection device in an assembled configuration, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 36  is an exploded perspective view illustration of the injection device of  FIG. 35 , constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 37A  is a perspective view illustration of the ring element of the injection device of  FIG. 35 , depicting a proximal surface thereof, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 37B  is a perspective view illustration of the ring element of  FIG. 37A , depicting a proximal surface thereof; 
         FIG. 38A  is a perspective view illustration of the electrical board of the injection device of  FIG. 35 , depicting a distal surface thereof, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 38B  is a perspective view illustration of the electrical board of  FIG. 38A , depicting a proximal surface thereof; 
         FIG. 39A  is an orthographic view illustration of the rack of the injection device of  FIG. 35 , constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 39B  is a perspective view illustration of the rack of  FIG. 39A ; 
         FIG. 40  is a perspective view illustration of the cap of the injection device of  FIG. 35 , depicting a proximal view thereof, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 41A  is a perspective view illustration of the plunger of the injection device of  FIG. 35 , with the cap removed, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 41B  is an orthographic view illustration of the plunger view of  FIG. 41A ; 
         FIG. 41C  is a sectional view illustration of the plunger view of  FIG. 41B ; 
         FIG. 42A  is an orthographic view illustration of the plunger of the injection device of  FIG. 35 , in an initial operational state, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 42B  is a sectional view illustration of the plunger view of  FIG. 42A ; 
         FIG. 42C  is a detailed view illustration of a first portion of the plunger view of  FIG. 42B ; 
         FIG. 42D  is a detailed view illustration of a second portion of the plunger view of  FIG. 42B ; 
         FIG. 43A  is an orthographic view illustration of the plunger of the injection device of  FIG. 35 , in a subsequent operational state, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 43B  is a sectional view illustration of the plunger view of  FIG. 43A ; 
         FIG. 43C  is a detailed view illustration of a first portion of the plunger view of  FIG. 43B ; 
         FIG. 43D  is a detailed view illustration of a second portion of the plunger view of  FIG. 43B ; 
         FIG. 44A  is an orthographic view illustration of the plunger of the injection device of  FIG. 35 , in a yet subsequent operational state, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 44B  is a sectional view illustration of the plunger view of  FIG. 44A ; 
         FIG. 44C  is a detailed view illustration of a first portion of the plunger view of  FIG. 44B ; 
         FIG. 44D  is a detailed view illustration of a second portion of the plunger view of  FIG. 44B ; 
         FIG. 45A  is an orthographic view illustration of the injection device of  FIG. 35  when in an initial operational state, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 45B  is an orthographic sectional view illustration of the injection device of  FIG. 45A ; 
         FIG. 46A  is an orthographic view illustration of the injection device of  FIG. 35 , prior to the needle insertion with the rigid needle shield (RNS) removed, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 46B  is an orthographic sectional view illustration of the injection device of  FIG. 46A ; 
         FIG. 47A  is an orthographic view illustration of the injection device of  FIG. 35  at a subsequent operational state with the plunger rod partially depressed, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 47B  is a sectional orthographic view illustration of the injection device of  FIG. 47A ; 
         FIG. 48A  is an orthographic view illustration of the injection device of  FIG. 35  at a later operational state with the plunger rod fully depressed, constructed and operative in accordance with a fourth embodiment of the present invention; 
         FIG. 48B  is a sectional orthographic view illustration of the injection device of  FIG. 48A . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The present invention overcomes the disadvantages of the prior art by providing injection devices with dosage monitoring capabilities. The injection devices of the present invention provide reliable and cost-effective techniques for remotely monitoring the usage of the syringe, including measuring and monitoring dosages of injected substances, which can allow for self-administering of injections, and precluding the need for qualified medical personnel or visitation to a medical facility. The dosage quantities and other injection information can also be monitored and analyzed to facilitate subsequent decisions regarding injections and associated treatments, such as to determine quantities of various medications to manufacture or order, and to monitor proper injections. 
     Reference is now made to  FIGS. 1 through 12 , which collectively illustrate an injection device, generally referenced  10 , according to a first embodiment of the present invention. Injection device  10  includes a syringe  100 , a gripping unit  110 , a ring element  120 , a plunger  130 , a rotor  140 , a cap  150 , and an electronics unit  160 , shown in an exploded view illustration in in  FIG. 2 . Injection device  10  has a distal end and a proximal end, which is depicted in the context of  FIG. 1 , where the distal end faces away from a user holding device  10  and towards the injection site. Injection device  10  is also defined by a longitudinal axis, extending lengthwise along the device between the proximal and distal ends, where an “axial” direction corresponds to a direction parallel to the longitudinal axis (i.e., towards or away from the proximal or distal ends), whereas a “radial” direction corresponds to a direction orthogonal to the longitudinal axis, and extending radially therefrom. 
     Syringe  100  includes a cylindrical chamber  101 , which is bordered at its proximal end by a gripping unit  110 . Syringe  100  further includes a needle  104  (shown in  FIG. 11 ) which is positioned within syringe chamber  101  and extends distally from the distal end of syringe  100 . Syringe  100  further includes a plunger stopper  102  (shown in  FIG. 9C ) positioned within syringe chamber  101  and configured to push out the injectant substance (e.g., a drug or medication) through needle  104 . Syringe further include a syringe flange  103  (shown in  FIG. 9C ), which is a short circular protrusion that projects radially outwards at the proximal end of syringe chamber  101 . A rigid needle shield (RNS)  105  ( FIG. 9A ) is configured to cover the distal end of the syringe needle  104  when injection device  100  is not in use, and to be removed before an injection, to maintain sterilization of the needle  104  and the injectant substance and protect against contamination and needlestick injury. 
     Reference is now made to  FIG. 3 , which an illustration of gripping unit  110  of injection device  10 . Gripping unit  110  includes a pair of finger grippers  111 , an annular surface  112 , a central opening  113 , and a pair of flange snaps  114 . Finger grippers  111  are arranged symmetrically on opposing sides. Each finger gripper  111  is a ledge of protrusion that projects radially outwards from gripping unit  110 , to enable a user to press his/her fingers against the finger grippers  111  to provide a counterforce when depressing plunger  130 . Central opening  113  allows components of injection device  10 , such as plunger rod  136 , and rotor rod  141 , to extend through opening  113  of gripping unit  110  and into the syringe chamber  101 , such as during an injection. Snaps  114  are symmetrically arranged on opposing side of surface  112 , perpendicularly to finger grippers  111 , where each snap  114  is a short protrusion that projects proximally. Snaps  114  are configured to clip onto syringe flange  103  during the assembly process to hold syringe  100  in place relative to gripping unit  110 , where syringe flange  103  contacts gripping unit  110  at annular surface  112 . 
     Reference is now made to  FIG. 4 , which an illustration of ring element  120  of injection device  10 . Ring element  120  is annular shaped with a central axial opening and a proximal annular surface  121 . A guiding pin  122  extends radially inward from an inner wall of ring element  120 . Guiding pin  122  is a fixed solid pin, and is configured to enable the rotation of rotor  140 , as will be elaborated upon further hereinbelow. Ring element  120  is disposed at the proximal end of syringe  100 . It is noted that ring element  120  may be substantially circular or may be a non-circular annular shape. 
       FIGS. 5A, 5B, 5C and 5D  provide illustrative views of plunger  130  of injection device  10 . Plunger  130  is characterized by a tubular rod  136  with a hollow core and aligned longitudinally. Plunger rod  136  is slidably advanceable within the syringe chamber, such that when plunger rod  136  is pushed in a distal direction, such as upon the manual application of force against finger grippers  111  of gripping unit  110 , an injectant substance contained within the chamber is ejected distally through the needle aperture. In particular, a plunger rod ending  132  at the distal end of plunger rod  136  is coupled to a syringe piston  102  of syringe  100 , such that the distal displacement of plunger rod  136  within syringe chamber  101  causes rod ending  132  to press against syringe piston  102  and forcing the distal displacement of the injectant substance. Plunger  130  includes a plunger head  131  at the proximal end of plunger rod  136 . Plunger head  131  is configured as a receptacle, with a circular disc shaped exterior perimeter and an interior perimeter defined by opposing semicircular edges and opposing straight edges (as seen in  FIG. 2 ), and a flat surface orthogonal to the longitudinal axis. Plunger head  131  is configured to contain rotor head  143  and electronics unit  160 , and be covered by cap  150 . Accordingly, the interior of plunger head  131  is shaped to conform to the perimeter shape of electronics unit  160 , such as including straight edges  135  to align with straight edges  153  of cap  150  and straight edges  167  of electronics unit  160  while allowing for rotation of circular rotor head  143 . Plunger  130  further includes a longitudinal slot  133  extending axially on an outer surface of plunger rod  136 . Guiding pin  122  embeds within longitudinal slot  133  so as to prevent rotation of ring element  120  with respect to the plunger  130 , while allowing linear displacement of plunger rod  136 . Plunger  130  is characterized with a central aperture  134  extending axially through plunger rod  136 . Plunger  130  is concentrically disposed within syringe  100 , with ring element  120  encircling plunger rod  136 . 
     Reference is now made to  FIGS. 6A and 6B , which provide illustrative views of rotor  140  of injection device  10 . Rotor  140  is characterized by a tubular rod  141  aligned longitudinally and having a screw thread  142  extending in a helical pattern along the length of rod  141 . Rotor  140  further includes a rotor head  143  positioned at the proximal end of rod  141 , and shaped as a circular disc aligned radially, such that the disc surface is orthogonal to the axial body of rotor rod  141 . Rotor head  143  is configured to rotate radially (i.e., about the longitudinal axis). A plurality of rotor head apertures  144  are arranged in a radial pattern along the surface of rotor head  143 , such as in the form of multiple rectangular (or other shaped) spacings extending from the core to the perimeter of rotor head  143  and positioned relatively close to one another. Rotor  140  further includes a rotor opening  145 , extending axially from the center of rotor head  143  through the core of rotor rod  141 , and terminating at a rotor rod ending protrusion  146  positioned at the distal end of rod  141 . Rotor rod ending protrusion  146  serves to reduce friction when rotor  140  is rotating within plunger  130  by reducing the surfaces in contact between rotor rod  141  and plunger rod  136 . Rotor  140  is concentrically disposed within plunger  130 , such that rotor rod  141  is disposed within plunger rod  136  and rotor head  143  is contained within plunger head  131 . Guiding pin  122  of ring element  120  interfaces with helical screw thread  142  of rotor rod  141  through plunger rod slot  133 , which provides a counterforce to turn rotor rod  141  and cause rotation of rotor  140  when plunger rod  136  is linearly displaced within syringe  100 . Ring element  120  is prevented from rotating with respect to plunger  130  by guiding pin  122  being embedded within plunger rod slot  133 , which limits guiding pin  122  to linear (axial) motion and prevents rotation of ring element  120 . 
     Reference is now made to  FIGS. 7A and 7B , which provide illustrative views of cap  150  of injection device  10 . Cap  150  is configured to contain electronics unit  160  and be embedded within plunger head  131 . Accordingly, the perimeter of cap  150  is shaped to conform to the perimeter shape of electronics unit  160  and plunger head  131 , with a perimeter defined by opposing semicircular edges and opposing straight edges  153  to align with straight edges  167  of electronics unit  160  and straight edges  135  of plunger head  131 . Cap  150  includes a flat proximal surface  151  (shown in  FIG. 7A ). Cap  150  further includes a battery enclosure  152 , which is shaped and sized to accommodate a battery of electronics unit  160  (e.g., a circular battery). Cap  150  may further include additional enclosures in the cap interior, which are shaped and sized to accommodate additional components of electronics unit  160  (described further hereinbelow). Cap  150  covers the proximal end of electronics unit  160  and rotor head  143 , and is embedded within plunger head  131 . 
     Reference is now made to  FIGS. 8A and 8B , which provide illustrative views of electronics unit  160  of injection device  10 . Electronics unit  160  includes a main circuit board  161 , on which is mounted a battery  162 , a controller  163 , an antenna  164 , an indicator  165 , and a sensor  166 . Circuit board  161  may also include additional electronic components or sensors not shown, such as: a temperature sensor, a gyroscope, an accelerometer, and an optical sensor. Battery  162  is configured to power at least some of the electronic components on circuit board  161 , such as controller  163 , indicator  165 , and sensor  166 . Controller  163  is configured to control the operation of at least some of the electronic components on circuit board, such as to control signal transmission through antenna  164 , and to control operation of indicator  165 , and sensor  166 . Controller  163  may also function as a connectivity module as well, or there may be separate modules. Antenna  164  is configured to transmit and/or receive data signals, such as to transmit a signal representative of injectant dosage information, to a remote location. For example, data signals may be transmitted to a personal computing device (e.g., a smartphone or tablet computer) of a patient or a medical operator, and/or to a data storage unit (e.g., a cloud storage service). Antenna  164  may transmit/receive signals over any suitable data communication channel or network, using any type of channel or network model or any data transmission protocol (e.g., wired, wireless, radio, WiFi, Bluetooth, and the like). Indicator  165  is configured to provide an indication relating to the operation or status of device. For example, indicator  165  may be a visual indicator configured to provide a visual indication, such as an LED, which lights up in a selected manner to reflect a particular device status. For example, indicator  165  may flash or blink at a certain frequency and/or illuminate in a certain color when an injection is in progress, and indicator  165  may flash or blink at a different frequency and/or illuminate in a different color when the injection is completed. Sensor  166  is positioned on circuit board  161  such that the sensor detection surface  166   a  faces the proximal side of rotor head  143 . Sensor  166  is configured to detect at least one property relating to the position and movement of rotor head  143 . For example, sensor  166  may be configured to detect a rotational motion of rotor head  143 , by detecting the sequential rotation of rotor disc apertures  144  over a selected duration of time. For example, sensor  166  may be configured to detect each time a rotor head aperture  144  passes across the sensor detection surface  166   a  during the rotation of rotor head  143 , by detecting the sequential passage of light through rotor head apertures  144 . Alternatively, sensor  166  may be configured to detect a different property relating to the movement of rotor head  143 , such as a magnetic change, a capacitance change, an inductance change, an impedance change, an acoustic change, a mechanical detection of rotor head apertures  143 , and the like. In general, sensor  166  may be operative to detect and sample electromagnetic radiation at any range of wavelengths (e.g., visible or non-visible light, infrared, ultraviolet, radar, microwave, RF), which may be converted into an electronic signal for subsequent processing and/or transmission. For example, sensor  166  may be embodied by an optical sensor, such as an infrared (IR) sensor. Controller  163  may process the detection samples from sensor  166  and translate the samples into a value representing a linear axial displacement amount of plunger rod  136 , which in turn, may be indicative of an ejected dosage of an injected substance contained within syringe  100 . Electronics unit  160  is disposed on the proximal end of rotor head  143 , and is contained within cap  150  (on the proximal end thereof) and within plunger head  131  (on the distal end thereof). Accordingly, the perimeter of electronics unit  160  is shaped to conform to the perimeter shape of cap  150  and plunger head  131 , with a perimeter defined by opposing semicircular edges and opposing straight edges  167  to align with straight edges  153  of cap  150  and straight edges  135  of plunger head  131 . 
     It is noted that the functionality associated with each of the elements of injection device  10  may be distributed among multiple elements or may be performed by other elements of device  10 . For example, the functionality described with regard to sensor  166  or controller  163  may be alternatively or additionally implemented by multiple sensor elements or controller elements. 
     Injection device  10  may optionally include additional components not shown in the Figures. For example, the injection device may include a housing, configured to encase the device components and to allow the user to comfortably hold or grip the injection device. The injection device may further include transparent windows, configured to provide a view of the injectant substance during the injection process. 
       FIGS. 9A, 9B, and 9C  provide illustrative views of injection device  10  in an initial operational state, and  FIG. 10  illustrates rotor  140  and ring element  120  in the initial operational state. When injection device  10  is in a storage or non-operational state, syringe needle  104  and the distal end of syringe  100  is encased by RNS  105 , which acts as a barrier for the injectant substance contained in syringe chamber  101  and keeps the needle and the injectant substance sterile. To perform an injection, a user holds injection device  10 , such as with fingers positioned distally against finger grippers  111  of gripping unit  110  and a thumb positioned on a proximal end of plunger head  131 . RNS  105  is removed to expose needle  104  (as shown in  FIG. 11 ). The user inserts the exposed distal end of needle  104  into an injection site, such as a body area of a patient to be injected. The user then depresses plunger  130 , such as by pressing distally against plunger head  131  while applying a clamping force against finger grippers  111 , causing plunger rod  136  to advance in the distal direction within syringe chamber  101 .  FIGS. 12A, 12B, and 12C  provide illustrative views of injection device  10  at a later operational state with the plunger rod fully depressed. The distal advancement of plunger rod  136  propels the injectant substance (shown in  FIGS. 9C and 12C ) distally within syringe chamber  101  to exit through the distal aperture of needle  104  and enter the injection site. 
     As plunger rod  136  advances distally within syringe chamber  101 , rotor rod  141  (shown in  FIG. 10 ) contained within plunger  130  advances distally as well, resulting in a corresponding rotational movement of rotor  140 . In particular, guiding pin  122  engages rotor rod screw thread  142  through plunger rod slot  133 , providing a counterforce to turn rotor rod  141  when plunger rod  136  is depressed. Guiding pin  122  is restricted to linear axial motion by plunger rod slot  133  which prevents rotation of ring element  120  with respect to plunger rod  136 . The depression of plunger rod  136  distally causes ring element  120  to rest against syringe flange  103  (seen in  FIG. 9C ), which forces the rotation of rotor  140  due to the aforementioned interactions among rotor rod  141 , plunger rod  136 , and guiding pin  122 . As rotor  140  rotates, sensor  166  detects the amount of rotational movement of rotor head  143 , such as by detecting the sequential passage of rotor disc apertures  144  across sensor detection surface  166   a . Controller  163  receives and processes the detection samples from sensor  166  to generate a value representative of a linear axial displacement of plunger rod  136 . The linear displacement value may then be converted to a value representative of an amount, such as a volume, of injected substance. Injection information, including an injected volume amount, along with other relevant information relating to the injection (e.g., time of injection, drug identification, expiration date, temperature), can then be transmitted via antenna  164  to a remote location, such as to a computing device (e.g., a smartphone or tablet computer) and/or a data storage unit (e.g., a cloud storage service). Alternatively, antenna  164  may transmit the detection samples directly from sensor  166  to a remote server or processor (e.g., at a cloud server), which performs the translation of the samples into linear displacement values and to an injected volume amount. The final injection information may be analyzed by relevant parties to draw conclusions. For example, the injection information may be used by drug manufactures to determine manufacturing quantities for various medications or drugs, or by hospitals or medical clinic staff to determine ordering quantities for such medications, and/or by doctors or medical professional to remotely monitor patient treatment, such as to ensure injections are properly carried out (e.g., to verify that the correct dosage amount was in fact injected, at the correct times and frequencies). 
     In accordance with an aspect of the present invention, at least some of the elements of injection device  10  may form a unified assembly which may be integrated with an existing syringe (e.g., a separate “add-on device”). For example, ring element  120 , plunger  130 , rotor  140 , cap  150 , and/or electronics unit  160 , may be configured as a unified device or assembly, which can be integrated with a standard syringe known in the art, such as by replacing a standard plunger and other associated syringe components. 
     Reference is now made to  FIGS. 13 through 24 , which collectively illustrate an injection device, generally referenced  20 , according to a second embodiment of the present invention. Injection device  20  is generally analogous to injection device  10  of the first embodiment, with selected differences, such as that the electronic components are disposed within the gripping unit in injection device  20 , rather than within a plunger head of the plunger as with injection device  10 . Furthermore, the guiding pin is embedded with the rotor disc, rather than with a separate ring element, and rather than included a threaded rotor rod, the plunger of injection device  20  is configured with a threaded surface. 
     Injection device  20  includes a syringe  100 , a gripping unit  210 , a plunger  230 , a rotor  220 , a cap  250 , and an electronics unit  260 , shown in an exploded view illustration in in  FIG. 14 . Injection device  20  has a distal end and a proximal end, which is depicted in  FIG. 13 , where the distal end faces away from a user holding device  20  and towards the injection site. Injection device  20  is also defined by a longitudinal axis, extending lengthwise along the assembly between the proximal and distal ends, where an “axial” direction corresponds to a direction parallel to the longitudinal axis (i.e., towards or away from the proximal or distal ends), whereas a “radial” direction corresponds to a direction orthogonal to the longitudinal axis, and extending radially therefrom. 
     Syringe  100  of injection device  20  is a standard syringe which is identical to syringe  100  of injection device  10 . 
     Gripping unit  210  of injection device  20  (illustrated in  FIGS. 15A and 15B ) is similar to gripping unit  100  of injection device  10  (illustrated in  FIG. 3 ). Gripping unit  210  includes a pair of finger grippers  211 , an annular surface  212 , a central opening  213 , and a pair of snaps  214 . Finger grippers  211  are arranged symmetrically on opposing sides. Each finger gripper  211  is a ledge or protrusion that projects radially outwards from gripping unit  210 , to enable a user to press his/her fingers against the finger grippers  211  to provide a counterforce when depressing plunger  230 . Central opening  213  allows components of injection device  20 , such as plunger rod  231 , to extend through gripping unit  210  into the syringe chamber  101 , such as during an injection. Accordingly, central opening  213  is sized and shaped to conform to the cross-sectional size and shape of plunger rod  231 , so as to allow plunger rod  231  to pass therethrough. For example, central opening  213  includes opposing straight edges  215 , to align with straight edges  235  of plunger  230 . Snaps  114  are symmetrically arranged on opposing sides of surface  212 , perpendicularly to finger grippers  211 , where each snap  214  is a short protrusion that projects proximally. Snaps  214  are configured to clip onto syringe flange  103  during the assembly process to hold syringe  100  in place relative to gripping unit  210 , where syringe flange  103  contacts gripping unit  210  at annular surface  212 . 
     Reference is now made to  FIG. 16 , which an illustration of rotor  220  of injection device  20 . Rotor  220  includes a circular disc shaped rotor surface  221  aligned orthogonal to the axial direction. A plurality of rotor apertures  223  are arranged in a radial pattern along rotor surface  221 , such as in the form of multiple rectangular (or other shaped) spacings extending from the core to the perimeter of rotor surface  221  and positioned relatively close to one another. Rotor  220  is characterized by a central opening, with a diameter at least large enough to accommodate the diameter of plunger rod  231 . Rotor  220  further includes one or more guiding pins  222 , extending radially inward from an inner wall of rotor  240 . For example, rotor  220  may include three guiding pins  222  equidistant from one another. Rotor  220  is configured to rotate radially (i.e., about the longitudinal axis). Rotor  220  is contained within gripping unit  210 , disposed on the proximal end of gripping unit surface  212 , and positioned distally from electronics unit  260  and cap  250 . 
     Reference is now made to  FIGS. 17A and 17B , which provide illustrative views of cap  250  of injection device  20 . Cap  250  is configured to contain electronics unit  260  and be embedded within gripping unit  210 . Accordingly, the perimeter of cap  250  is shaped to conform to the perimeter shape of electronics unit  260  and gripping unit  210 , with a perimeter defined by opposing semicircular edges and opposing straight edges  254  to align with straight edges  267  of electronics unit  260  and straight edges of gripping unit  210 . Cap  250  includes a flat proximal surface  251  (shown in  FIG. 17B ). Cap  250  further includes a battery enclosure  252 , which is shaped and sized to accommodate a battery of electronics unit  260  (e.g., a circular battery). Cap  250  further includes a central opening  253 , which is shaped and sized to accommodate plunger rod  231 , such as including straight edges  255  to align with straight edge  235  of plunger rod  231 . Accordingly, battery enclosure  252  may be smaller than battery enclosure  152  of cap  150  of device  10 , so as to accommodate central opening  253  (which is not present in cap  150 ). Cap  250  may further include additional enclosures in the cap interior, which are shaped and sized to accommodate additional components of electronics unit  260  (described further hereinbelow). Cap  250  covers the proximal end of electronics unit  260  and rotor  220 , and is embedded within gripping unit  210 . 
     Reference is now made to  FIGS. 18A and 18B , which provide illustrative views of electronics unit  260  of injection device  20 . Electronics unit  260  includes a main circuit board  261 , on which is mounted a battery  262 , a controller  263 , an antenna  264 , an indicator  265 , and a sensor  266 . Electronics unit  260  is generally analogous to electronics unit  160  of injection device  10  (illustrated in  FIGS. 8A and 8B ), but electronics unit  260  further includes a central opening  268 , which is shaped and sized to accommodate plunger rod  231 . Accordingly, battery  262  may be smaller than battery  162 , so as to accommodate central opening  268  (which is not present in electronics unit  160 ). Sensor  266  is configured to detect at least one property relating to the position and movement of rotor  220 . For example, sensor  266  may be configured to detect a rotational motion of rotor  220 , such as by detecting the sequential rotation of rotor apertures  223  over time, such as by detecting the sequential passage of light onto the sensor detection surface  266   a  through a selected rotor aperture  223 . Alternatively, sensor  266  may be configured to detect a different property relating to the movement of rotor  220 , such as a magnetic change, a capacitance change, an inductance change, an impedance change, an acoustic change, a mechanical detection of rotor apertures  223 , and the like. In general, sensor  266  may be operative to detect and sample electromagnetic radiation at any range of wavelengths (e.g., visible or non-visible light, infrared, ultraviolet, radar, microwave, RF), which may be converted into an electronic signal for subsequent processing and/or transmission. Electronics unit  260  is disposed on the proximal end of rotor  220 , and is contained within cap  250  (on the distal end thereof) and within gripping unit  210  (on the proximal end thereof). Accordingly, the perimeter of electronics unit  260  is shaped to conform to the perimeter shape of cap  250  and gripping unit  210 , with a perimeter defined by opposing semicircular edges and opposing straight edges  267  to align with straight edges of cap  250  and gripping unit  210 , respectively. 
     Reference is now made to  FIGS. 19 and 20 , which provide illustrative views of plunger  230  of injection device  20 . Plunger  230  includes a tubular plunger rod  231  aligned longitudinally. Plunger rod  231  is characterized by a screw thread  232  extending in a helical pattern along the length of rod  231 . A plunger finger press  233  is positioned at the proximal end of plunger  230  and characterized by a circular disc defining a radial surface orthogonal to the longitudinal axis. Plunger rod  231  is slidably advanceable within syringe chamber  101 , such that when plunger  230  is pushed in a distal direction, such as upon the manual application of force against plunger finger press  231  and finger grippers  211 , an injectant substance contained within syringe chamber  101  is ejected distally through the needle aperture. In particular, a plunger rod ending  234 , at the distal end of plunger rod  231 , is coupled to a syringe piston  102  of syringe  100 , such that the distal displacement of plunger rod  231  within syringe chamber  100  causes plunger rod ending  234  to press against syringe piston  102  and forcing a distal displacement of the injectant substance. Plunger  230  is concentrically disposed within syringe  100 , such that plunger rod  231  extends axially through central opening  213  of gripping unit  210 , through the central opening of rotor  220 , through central opening  253  of cap  250 , and through central opening  268  of electronics unit  260 . Straight edge  235  of plunger rod  231  is a straight flat edge surface aligned with straight edge  215  of gripping unit  210  and straight edge  255  of cap  250 , so as to prevent rotation of plunger rod  231  relative to gripping unit  210 , and prevent a corresponding rotation of rotor  220 , which may result in false detection readings by sensor  266 . 
       FIGS. 21A, 21B, and 21C  provide illustrative views of rotor  220  and sensor  266  of injection device  20 . 
     It is noted that the functionality associated with each of the elements of injection device  20  may be distributed among multiple elements or may be performed by other elements of device  20 . Injection device  20  may optionally include additional components not shown in the Figures. For example, the injection device may include a housing, configured to encase the device components and to allow the user to comfortably hold or grip the injection device. The injection device may further include transparent windows, configured to provide a view of the injectant substance during the injection process. 
       FIGS. 22A, 22B, and 22C  provide illustrative views of injection device  20  in an initial operational state. When injection device  20  is in a storage or non-operational state, syringe needle  104  and the distal end of syringe  100  is encased by RNS  105 . To perform an injection, a user holds injection device  20 , such as with fingers positioned distally against finger grippers  211  of gripping unit  210  and a thumb positioned against plunger finger press  233 . RNS  105  is removed to expose needle  104  (as shown in  FIG. 23 ). The user inserts the exposed distal end of needle  104  into an injection site, such as a body area of a patient to be injected. The user then depresses plunger  230 , such as by pressing distally against plunger finger press  233  while applying a clamping force against finger grippers  211 , causing plunger rod  231  to advance in a distal direction within syringe chamber  101 .  FIGS. 24A and 24B  provide illustrative views of injection device  20  at a later operational state with the plunger rod fully depressed. The distal advancement of plunger rod  231  propels the injectant substance distally within syringe chamber  101  to exit through the distal aperture of needle  104  and enter the injection site. 
     The linear distal displacement of plunger rod  231  within syringe chamber  101  results in a corresponding rotational movement of rotor  220 . In particular, guiding pins  222  of rotor  220  engages plunger rod screw thread  232 , providing a counterforce to turn rotor  220  relative to plunger rod  231 . As rotor  220  rotates, sensor  266  detects the amount of rotational movement of rotor  220 , such as by detecting the sequential passage of rotor disc apertures  223  across sensor detection surface  266   a . Plunger rod  231  is restricted from rotating with respect to gripping unit  210  due to the orientation of plunger rod straight edge  235  and shape of gripping unit central opening  213 , which prevents sensor  266  from detecting irrelevant rotations of rotor  220  during a non-injection. Controller  263  receives and processes the detection samples from sensor  266  to generate a value representative of a linear axial displacement of plunger rod  231 . The linear displacement value may then be converted to a value representative of an amount, such as a volume, of injected substance. Injection information, including an injected volume amount, along with other relevant information relating to the injection (e.g., time of injection, drug identification, expiration date, temperature), can then be transmitted via antenna  264  to a remote location, such as to a computing device (e.g., a smartphone or tablet computer) and/or a data storage unit (e.g., a cloud storage service). Alternatively, antenna  264  may transmit the detection samples directly from sensor  266  to a remote server or processor (e.g., at a cloud server), which performs the translation of the samples into linear displacement values and to an injected volume amount. The final injection information may be analyzed by relevant parties to draw conclusions. For example, the injection information may be used by drug manufactures to determine manufacturing quantities for various medications or drugs, or by hospitals or medical clinic staff to determine ordering quantities for such medications, and/or by doctors or medical professionals to remotely monitor patient treatment, such as to ensure injections are properly carried out (e.g., to verify that the correct dosage amount was in fact injected, at the correct times and frequencies). In accordance with an aspect of the present invention, at least some of the elements of injection device  20  may form a unified assembly which may be integrated with an existing syringe (e.g., a separate “add-on device”). For example, gripping unit  210 , plunger  230 , rotor  220 , cap  250 , and/or electronics unit  260 , may be configured as a unified device or assembly, which can be integrated with a standard syringe known in the art, such as by replacing a standard plunger and other associated syringe components. 
     It will be appreciated that injection devices  10  and  20  allows for remote processing and analysis of information relating to an injection process, such as quantities, times and frequencies of injection dosages. The injection information can also be monitored and analyzed to facilitate subsequent decisions regarding injections and associated treatments, such as to determine quantities of various medications to manufacture or order, and to enable remote monitoring of injections by doctors or health care personnel. For example, injection devices  10  and  20  may provide remote monitoring and verification of the injection process, by allowing verification that an injection was properly carried out, with the correct dosage amount and at a correct time and frequency. 
     Reference is now made to  FIGS. 25 through 34 , which collectively illustrate an injection device, generally referenced  30 , according to a third embodiment of the present invention. Injection device  30  includes a syringe  100 , a gripping unit  310 , an electronics unit  320 , a cap  330 , and a plunger  340 , shown in an exploded view illustration in in  FIG. 26 . Injection device  30  has a distal end and a proximal end, which is depicted in  FIG. 25 , where the distal end faces away from a user holding device  30  and towards the injection site. Injection device  30  is also defined by a longitudinal axis, extending lengthwise along the assembly between the proximal and distal ends, where an “axial” direction corresponds to a direction parallel to the longitudinal axis (i.e., towards or away from the proximal or distal ends), whereas a “radial” direction corresponds to a direction orthogonal to the longitudinal axis, and extending radially therefrom. 
     Syringe  100  of injection device  30  is a standard syringe which is identical to syringe  100  of injection device  10 . 
     Gripping unit  310  of injection device  30  (illustrated in  FIGS. 27A and 27B ) is similar to gripping unit  210  of injection device  20  (illustrated in  FIGS. 15A and 15B ). Gripping unit  310  includes a pair of finger grippers  311 , an annular surface  312 , a central opening  313 , and a pair of snaps  314 . Finger grippers  311  are arranged symmetrically on opposing sides, where each finger gripper  311  is a ledge of protrusion that projects radially outwards from gripping unit  310 , to enable a user to press his/her fingers against the finger grippers  311  to provide a counterforce when depressing plunger  340 . Central opening  313  allows plunger rod  341  to extend through gripping unit  310  into the syringe chamber  101 , such as during an injection. Accordingly, central opening  313  is sized and shaped to conform to the cross-sectional size and shape of plunger rod  341 , so as to allow plunger rod  341  to pass therethrough. For example, central opening  313  includes opposing edges  315  to align with teeth  342  of plunger rod  341 . Snaps  314  are symmetrically arranged on opposing sides of surface  312 , perpendicularly to finger grippers  311 , where each snap  314  is a short protrusion that projects proximally. Snaps  314  are configured to clip onto syringe flange  103  during the assembly process to hold syringe  100  in place relative to gripping unit  310 , where syringe flange  103  contacts gripping unit  310  at annular surface  312 . 
     Reference is now made to  FIGS. 28A and 28B , which provide illustrative views of cap  330  of injection device  30 . Cap  330  is configured to contain electronics unit  320  and be embedded within gripping unit  310 . Accordingly, the perimeter of cap  330  is shaped to conform to the perimeter shape of electronics unit  320  and gripping unit  310 . Cap  330  includes a flat proximal surface  332  (shown in  FIG. 28A ). Cap  330  includes a rib  331  which protrudes distally from cap surface  332  and is configured to slide inside a corresponding slot within gripping unit  310  while extending over an edge  327  of electronics unit  320 . Cap  330  further includes a sensor enclosure  334 , which is shaped and sized to accommodate sensor  366  of electronics unit  320 . Cap  330  may further include additional enclosures in the cap interior, which are shaped and sized to accommodate additional components of electronics unit  320 . Cap  330  further includes a central opening  333  shaped and sized to accommodate the cross-sectional shape of plunger rod  341 , so as to allow plunger rod  341  to pass through central opening  333 . Cap  330  covers the proximal end of electronics unit  320  and is embedded within gripping unit  310 . 
     Reference is now made to  FIGS. 29A and 29B , which provide illustrative views of electronics unit  320  of injection device  30 . Electronics unit  320  includes a main circuit board  321 , on which is mounted a battery  322 , an antenna  324 , an indicator  325 , a controller  326 , and a sensor  366 . Electronics unit  320  is generally analogous to electronics unit  260  of injection device  20  (illustrated in  FIGS. 18A and 18B ), but the central opening of electronics unit  320  is sized and shaped to accommodate the plunger rod  341 . Sensor  366  is configured to detect at least one property relating to the position and movement of teeth  342  of plunger rod  341 . For example, sensor  366  may be configured to detect an axial displacement of plunger rod  341  by detecting the sequential displacement of teeth  342 , as will be described further hereinbelow. Sensor  366  may be embodied by an optical sensor device, or by an alternative type of sensor configured to detect a property relating to the movement of teeth  342  of plunger rod  341 , such as a magnetic change, a capacitance change, an inductance change, an impedance change, an acoustic change, a mechanical change, and the like. In general, sensor  366  may be operative to detect and sample electromagnetic radiation at any range of wavelengths (e.g., visible or non-visible light, infrared, ultraviolet, radar, microwave, RF), which may be converted into an electronic signal for subsequent processing and/or transmission. Electronics unit  320  is contained within cap  330  (on the distal end thereof), and within gripping unit  310  (on the proximal end thereof). 
     Reference is now made to  FIGS. 30, 31A and 31B , which provide illustrative views of plunger  340  and sensor  366  of injection device  30 . Plunger  340  includes a tubular plunger rod  341  aligned longitudinally. Plunger rod  341  is characterized by a strip of teeth  342  extending axially along a portion of the length of plunger rod  341 , while the remaining portion of plunger rod  341  has a substantially circular radial diameter. Teeth strip  342  is characterized by a series of tooth protrusions  342   a  interspersed with a series of tooth indentations  342   b , such that a respective tooth protrusion  342   a  is followed by a respective tooth indentation  342   b  which is followed by another tooth protrusion  342   a , and so forth. Each tooth protrusion  342   a  protrudes radially outwards from teeth strip  342 , and each tooth indentation  342   b  is indented radially inwards. Teeth strip  342  further includes a straight edge surface  344 , aligned with straight edges  315  of gripping unit  310 , so as to prevent rotation of plunger rod  341  relative to gripping unit  310 , and prevent false detection readings by sensor  366 . A plunger finger press  343  is positioned at the proximal end of plunger  340 . Finger press  343  is characterized by a circular disc defining a radial surface orthogonal to the longitudinal axis of plunger  340 . Plunger rod  341  is slidably advanceable within syringe chamber  101 , such that when plunger  340  is pushed in a distal direction, such as upon the manual application of force against plunger finger press  343  and finger grippers  311 , an injectant substance contained within syringe chamber  101  is ejected distally through the needle aperture. In particular, a plunger rod ending  345 , at the distal end of plunger rod  341 , is coupled to a syringe piston  102  of syringe  100 , such that the distal displacement of plunger rod  341  within syringe chamber  101  causes plunger rod ending  345  to press against syringe piston  102  and forcing a distal displacement of the injectant substance. Plunger  340  is concentrically disposed within syringe  100 , such that plunger rod  341  extends axially through central opening  313  of gripping unit  310 , through central opening  333  of cap  330 , and through the central opening of electronics unit  320 . 
     It is noted that the functionality associated with each of the elements of injection device  30  may be distributed among multiple elements or may be performed by other elements of device  30 . Injection device  30  may optionally include additional components not shown in the Figures. For example, the injection device may include a housing, configured to encase the device components and to allow the user to comfortably hold or grip the injection device. The injection device may further include transparent windows, configured to provide a view of the injectant substance during the injection process. 
       FIGS. 32A, 32B, 33, 34A and 34B  provide illustrative views of injection device  30  in an initial operational state. When injection device  30  is in a storage or non-operational state, syringe needle  104  and the distal end of syringe  100  is encased by RNS  105 . To perform an injection, a user holds injection device  30 , such as with fingers positioned distally against finger grippers  311  of gripping unit  310  and a thumb positioned against plunger finger press  343 . RNS  105  is removed to expose needle  104  (as shown in  FIG. 33 ). The user inserts the exposed distal end of needle  104  into an injection site, such as a body area of a patient to be injected. The user then depresses plunger  340 , such as by pressing distally against plunger finger press  343  while applying a clamping force against finger grippers  311 , causing plunger rod  341  to advance in a distal direction within syringe chamber  101 .  FIGS. 34A and 34B  provide illustrative views of injection device  30  at a later operational state with the plunger rod fully depressed. The distal advancement of plunger rod  341  propels the injectant substance distally within syringe chamber  101  to exit through the distal aperture of needle  104  and enter the injection site. 
     The linear distal displacement of plunger rod  341  within syringe chamber  101  results in the passage of teeth strip  342  through the openings of cap  330  and electronics unit  320 , and across the detection surface  366   a  of sensor  366 , which remains fixed within the stationary gripping unit  310 . During the linear advancement of plunger rod  341 , sensor  366  detects the displacement of teeth strip  342 , such as by detecting the sequential passage of tooth protrusions  342   a  across sensor detection surface  366   a . Plunger rod  341  is restricted from rotating with respect to gripping unit  310  due to the orientation of teeth strip straight edge  344  and the shape of gripping unit central opening  313 , which prevents irrelevant detection readings by sensor  366 . The sensor readings are received and processed by controller  326  to generate a value representative of a linear axial displacement of plunger rod  341 , which in turn may be converted to a value representative of an amount, such as a volume, of injected substance using a suitable conversion formula. Injection information, including an injected volume amount, along with other relevant information relating to the injection (e.g., time of injection, drug identification, expiration date, temperature), can then be transmitted via antenna  324  to a remote location, such as to a computing device (e.g., a smartphone or tablet computer) and/or a data storage unit (e.g., a cloud storage service). Alternatively, antenna  324  may transmit the detection samples directly from sensor  366  to a remote server or processor (e.g., at a cloud server), which performs the translation of the samples into linear displacement values and an injected volume amount. The final injection information may be analyzed by relevant parties to draw conclusions. For example, the injection information may be used by drug manufactures to determine manufacturing quantities for various medications or drugs, or by hospitals or medical clinic staff to determine ordering quantities for such medications, and/or by doctors or medical professionals to remotely monitor patient treatment, such as to ensure injections are properly carried out (e.g., to verify that the correct dosage amount was in fact injected, at the correct times and frequencies). 
     In accordance with an aspect of the present invention, at least some of the elements of injection device  30  may form a unified assembly which may be integrated with an existing syringe (e.g., a separate “add-on device”). For example, gripping unit  310 , electronics unit  320 , cap  330  and/or plunger  340 , may be configured as a unified device or assembly, which can be integrated with a standard syringe known in the art, such as by replacing a standard plunger and other associated syringe components. 
     Reference is now made to  FIGS. 35 through 48 , which collectively illustrate an injection device, generally referenced  40 , according to a fourth embodiment of the present invention. Injection device  40  includes a syringe  100 , a flexible ring  410 , a plunger  420 , a rack  430 , an electronics unit  440 , and a cap  450 , shown in an exploded view illustration in  FIG. 36 . Injection device  40  has a distal end and a proximal end, which is depicted in  FIG. 35 , where the distal end faces away from a user holding device  40  and towards the injection site. Injection device  40  is also defined by a longitudinal axis, extending lengthwise along the assembly between the proximal and distal ends, where an “axial” direction corresponds to a direction parallel to the longitudinal axis (i.e., towards or away from the proximal or distal ends), whereas a “radial” direction corresponds to a direction orthogonal to the longitudinal axis, and extending radially therefrom. 
     Syringe  100  of injection device  40  is a standard syringe which is identical to syringe  100  of injection device  30 . 
     Reference is now made to  FIGS. 37A and 37B , which provide illustrative views of flexible ring  410  of injection device  40 . Ring  410  includes a proximal ring surface  411  facing a proximal side of ring  410 , and a distal ring surface  415  facing a distal side of ring  410 . A first ring tooth  412  projects radially inwards from an inner surface of ring  410 . Ring tooth  412  includes a flat distal tooth surface  412   a  facing a distal direction, an inclined proximal tooth surface  412   b  facing a proximal direction, and an inner tooth surface facing radially inwards. A second ring tooth  416  projects radially inwards from an inner surface of ring  410  opposite first ring tooth  412 . Ring  410  further includes flexible portions  413 , arranged on opposing sides, with the surfaces of flexible portions  413  facing radially such that flexible portions  413  are configured to bend or deform radially inwards or radially outwards. Ring  410  is disposed around plunger rod  421  of plunger  420 , at a proximal end of syringe  100 . 
     Reference is now made to  FIGS. 38A and 38B , which provide illustrative views of electronics unit  440  of injection device  40 . Electronics unit  440  includes a main circuit board  441 , on which is mounted a battery  442 , an antenna  444 , an indicator  445 , a controller  443 , and a sensor  446 . Electronics unit  420  is generally analogous to electronics unit  160  of injection device  10  (illustrated in  FIGS. 8A and 8B ). Circuit board  441  may also include additional electronic components not shown. Battery  442  is configured to power at least some of the electronic components on circuit board  441  (such as controller  443 , indicator  445 , and sensor  446 ). Controller  443  is configured to control the operation of at least some of the electronic components on circuit board, such as to control antenna  444 , indicator  445  and/or sensor  446 . Antenna  444  is configured to transmit and/or receive data signals, such as to transmit a signal representative of injectant dosage information, to a remote location. Sensor  466  is configured to detect at least one property relating to the position and movement of rack  430 . For example, sensor  446  may be configured to detect an axial displacement of rack  430 , by detecting the sequential displacement of rack teeth  433 , as will be described further hereinbelow. Sensor  446  may be embodied by an optical sensor device, or by an alternative type of sensor configured to detect a property relating to the movement of rack teeth  433 , such as a magnetic change, a capacitance change, an inductance change, an impedance change, an acoustic change, a mechanical change, and the like. Indicator  445  is configured to provide an indication relating to the operation or status of device. For example, indicator  445  may be a visual indicator configured to provide a visual indication, such as an LED, which lights up in a selected manner to reflect a particular device status. Electronics unit  440  is covered by cap  450  (on the distal end thereof), and within plunger head  426  of plunger  420  (on the proximal end thereof). 
     Reference is now made to  FIGS. 39A and 39B , which provide illustrative views of rack  430  of injection device  40 . Rack  430  is disposed longitudinally within plunger  420 . Rack  430  includes a proximal rack surface  435  facing a proximal side of rack  430 , and a distal rack surface  431  facing a distal side of rack  430 . Rack  430  further includes a series of teeth  433  extending axially along the length of rack  430 , where teeth  430  are embodied by triangular shaped protrusions that project radially outwards when rack is positioned within plunger  420 . Each tooth  433  includes an inclined proximal tooth face  432  facing a proximal direction, and a distal tooth face  434  facing a distal direction. 
     Cap  450  of injection device  40  (illustrated in  FIG. 40 ) is configured to cover electronics unit  440  and be embedded within plunger head  426  of plunger  420 . Accordingly, the perimeter of cap  450  is circular in shape to conform to the circular perimeter shape of electronics unit  440  and plunger head  426 . Cap  450  includes a flat proximal cap surface  452  facing a proximal direction. 
     Reference is now made to  FIGS. 41A, 41B, and 41C , which provide illustrative views of plunger  420  of injection device  40 . Plunger  420  includes a hollow tubular plunger rod  421  aligned longitudinally. Plunger rod  421  is slidably advanceable within syringe chamber  101 , such that when plunger rod  421  is pushed in a distal direction, an injectant substance contained within syringe chamber  101  is ejected distally through the aperture of syringe needle  104 . A plunger rod ending  423  at the distal end of plunger rod  421  is coupled to a syringe piston  102  of syringe  100 , such that the distal displacement of plunger rod  421  within syringe chamber  101  causes rod ending  423  to press against syringe piston  102  and forcing the distal displacement of the injectant substance. Plunger  420  includes a plunger head  426  at the proximal end of plunger rod  421 . Plunger head  426  is configured as a receptacle with a circular disc shaped perimeter, and is configured to contain electronics unit  440  and cap  450 . Plunger head  426  contains an annular surface  424  and a protrusion  425 , configured to provide alignment during an assembly process, such as to facilitate alignment of components of electronics unit  420 . Rack  430  is concentrically disposed within the cavity of plunger rod  421 , with the distal rack surface  431  of rack  430  facing distally. Plunger rod  421  is characterized by a slot  422 , extending axially on an outer surface thereof, and terminating at a distal surface  427 . Plunger rod  421  is further characterized by an indentation  429  extending axially on an outer surface of plunger rod  421  opposite slot  422 . Rack teeth  433  are configured to protrude out from plunger rod slot  422  when rack  430  is disposed concentrically within plunger rod  421 . Ring tooth  412  of flexible ring  410  is embedded within plunger rod slot  422 . Ring tooth  416  is embedded within plunger rod indentation  429 , which together with ring tooth  412 , prevents rotation of ring  410  relative to plunger  420 , while allowing linear displacement of plunger rod  421  with respect to the ring  410 . Plunger  420  is concentrically disposed within syringe  100 , with ring  410  encircling plunger rod  421  at a proximal end of syringe  100 . 
     It is noted that the functionality associated with each of the elements of injection device  40  may be distributed among multiple elements or may be performed by other elements of device  40 . Injection device  40  may optionally include additional components not shown in the Figures. For example, injection device  40  may include a gripping unit with finger grippers (similar to gripping units  110 ,  210 ,  310 ) to facilitate depressing the plunger. Injection device  40  may also include a housing, configured to encase the device components and to allow the user to comfortably hold or grip the injection device. The injection device may further include transparent windows, configured to provide a view of the injectant substance during the injection process. 
       FIGS. 45A and 45B  provide illustrative views of injection device  40  in an initial operational state. When injection device  40  is in a storage or non-operational state, syringe needle  104  and the distal end of syringe  100  is encased by RNS  105 . To perform an injection, a user holds injection device  40 , such as with fingers positioned around syringe flange  103  (or finger grippers of a gripping unit) and a thumb positioned against cap  450  at the proximal end of plunger head  426 . RNS  105  is removed to expose needle  104 , as shown in  FIGS. 46A and 46B . The user inserts the exposed distal end of needle  104  into an injection site, such as a body area of a patient to be injected. The user then depresses plunger  420 , such as by pressing distally against plunger head  426  while applying a clamping force against syringe chamber  101 , causing plunger rod  421  to advance in a distal direction within syringe chamber  101 .  FIGS. 47A and 47B  provide illustrative views of injection device  40  at a subsequent operational state with the plunger rod partially depressed. The distal advancement of plunger rod  341  propels the injectant substance distally within syringe chamber  101  to exit through the distal aperture of needle  104  and enter the injection site.  FIGS. 48A and 48B  provide illustrative views of injection device  40  at a later operational state with the plunger rod fully depressed. 
     At the beginning of the injection, ring tooth  412  of flexible ring  410  engages with a rack tooth  433  of rack  430  situated within plunger rod  421 . When plunger rod  421  is pressed distally, rack  430  is also pressed distally but is restricted from distal displacement by flexible ring  410 , which results in a counterforce being applied by rack  430  in a proximal direction. The applied counterforce initiates the activation of sensor  446  and also initiates a radial expansion of flexible ring  410  due to the flexible nature of ring  410  and the inclined tooth faces  432  of rack teeth  433 . In particular, flexible ring portions  413  bend or deform radially. Flexible ring  410  continues to expand, until rack  430  is able to advance distally by a single rack tooth  433  which pushes through ring  410 , and is detected by sensor  446 .  FIGS. 42A, 42B, 42C and 42D  provide illustrative views of injection device  40  in an initial operational state, showing sensor  446  prior to activation and flexible ring  410  prior to expansion from a proximal counterforce applied by rack  430 .  FIGS. 43A, 43B, 43C and 43D  provide illustrative views of injection device  40  in a subsequent operational state, showing an intermediate activation stage of sensor  446 , in which rack  430  is in contact with sensor  446 , and an intermediate expansion stage of flexible ring  410  in which ring  410  begins to expand.  FIGS. 44A, 44B, 44C and 44D  provide illustrative views of injection device  40  in a yet subsequent operational state, showing a later activation stage of sensor  446  and later expansion stage of flexible ring  410 . Flexible ring  410  then contracts back to its initial shape, with flexible ring portions  413  deforming back to their previous resting orientation. The aforementioned cycle then repeats itself as plunger rod  421  continues to be depressed distally, resulting in another proximal counterforce applied by rack  430 , and another expansion of flexible ring  410  and corresponding distal advancement of a rack tooth  433  through flexible ring  410 . Sensor  446  detects the displacement of rack  430  by detecting rack surface  435  coming into contact with sensor detection surface  446   a . In particular, sensor  446  obtains a sensor reading each time a rack tooth advances through flexible ring  410 , where the counterforce applied by rack  430  and initial expansion of flexible ring  410  initiates the activation of sensor  446  by the proximal rack surface  435 . The cycle repeats itself for each rack tooth  433  of rack  430  until plunger rod  421  is fully depressed. 
     Controller  443  receives the sensor readings to generate a value representative of a linear axial displacement of plunger rod  421 , which in turn may be converted to a value representative of an amount, such as a volume, of injected substance using a suitable conversion formula. The distance between adjacent rack teeth  433  determines the volume of injectant substance injected by plunger rod  421  for each sensor reading. Injection information, including an injected volume amount, along with other relevant information relating to the injection (e.g., time of injection, drug identification, expiration date, temperature), can then be transmitted via antenna  444  to a remote location, such as to a computing device (e.g., a smartphone or tablet computer) and/or a data storage unit (e.g., a cloud storage service). Alternatively, antenna  444  may transmit the detection samples directly from sensor  446  to a remote server or processor (e.g., at a cloud server), which performs the translation of the samples into linear displacement values and an injected volume amount. The final injection information may be analyzed by relevant parties to draw conclusions. For example, the injection information may be used by drug manufactures to determine manufacturing quantities for various medications or drugs, or by hospitals or medical clinic staff to determine ordering quantities for such medications, and/or by doctors or medical professionals to remotely monitor patient treatment, such as to ensure injections are properly carried out (e.g., to verify that the correct dosage amount was in fact injected, at the correct times and frequencies). 
     In accordance with an aspect of the present invention, at least some of the elements of injection device  40  may form a unified assembly which may be integrated with an existing syringe (e.g., a separate “add-on device”). For example, flexible ring  410 , plunger  420 , rack  430 , electronics unit  440 , and/or cap  450 , may be configured as a unified device or assembly, which can be integrated with a standard syringe known in the art, such as by replacing a standard plunger and other associated syringe components. 
     It will be appreciated that injection devices  30  and  40  allows for remote processing and analysis of information relating to an injection process, such as quantities, times and frequencies of injection dosages. The injection information can also be monitored and analyzed to facilitate subsequent decisions regarding injections and associated treatments, such as to determine quantities of various medications to manufacture or order, and to enable remote monitoring of injections by doctors or health care personnel. For example, injection devices  30  and  40  may provide remote monitoring and verification of the injection process, by allowing verification that an injection was properly carried out, with the correct dosage amount and at a correct time and frequency. 
     While certain embodiments of the disclosed subject matter have been described, so as to enable one of skill in the art to practice the present invention, the preceding description is intended to be exemplary only. It should not be used to limit the scope of the disclosed subject matter, which should be determined by reference to the following claims.