Apparatus and method for measuring dose in injector

Provided is an apparatus and method for measuring a dose in an injector, which is capable of measuring a dose without modifying the mechanical structure of the injector. A number sleeve is provided to pass through an injector body and is connected to be spirally movable, and a pattern for dose measurement is formed on an outer periphery of the number sleeve. The injector body includes a sensor for sensing the pattern formed on the number sleeve when the number sleeve performs a spiral movement, and a controller for measuring a dose according to a spiral movement distance of the number sleeve through the sensor.

PRIORITY

This application claims priority under 35 U.S.C. §119(a) to a Korean Patent Application filed in the Korean Intellectual Property Office on Jul. 21, 2010 and assigned Serial No. 10-2010-0070547, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an apparatus and method for measuring a dose in an injector, and more particularly, to an apparatus and method for measuring a dose in an injector, which is capable of measuring a dose without modifying the mechanical structure of the injector.

2. Description of the Related Art

A type 1 diabetic patient's body does not produce enough insulin that is essential to survival, so he or she needs to continuously measure a blood glucose level and inject an appropriate dose of insulin. Currently, an insulin pen that conveniently allows a user to personally inject insulin has been distributed on the markets. The insulin pen is designed to determine a specific dose by turning a dose-marked knob, and inject insulin by pressing a button disposed at the end of the insulin pen.

A patient records information about when and how much insulin is injected, and his or her medical attendant checks the recorded information to determine whether a patient's disease state is controlled, thereby increasing the effect of treatment.

However, for an insulin pen which allows an individual to adjust and inject a specific dose of insulin personally according to an aperiodically checked glucose level, as well as a complicated system like an insulin pump which measures a glucose level for twenty-four hours in real time and continuously injects a slight dose of insulin, there are no inexpensive methods for checking when and how much insulin is injected and transmitting the checked information.

To conventionally measure a dose of insulin, an amount of insulin in a syringe containing an injection liquid or a position of a syringe piston is measured. For an insulin pump similar to an insulin pen, the number of revolutions of a motor and a screw for moving a syringe piston is measured.

However, the above-mentioned techniques are difficult to apply to the structures of insulin pens that are available on the markets.

With a currently used insulin pen, a user determines a dose by turning a number sleeve of the insulin pen and, when the user presses a button disposed at the end of the insulin pen, a screw provided in the number sleeve is connected to a clutch and performs a spiral movement to move a piston forward within in an insulin injector. In other words, a screw nut is not moved during a rotary movement of the screw, and the screw moves forward while performing a spiral movement. When the screw performs only a rotary movement, it is easy to measure the number of revolutions corresponding to a spiral movement distance. However, when the screw directly moves forward while performing a spiral movement, it is difficult to measure the number of revolutions of the screw.

Moreover, when a dose is measured using a capacitance/inductance/optical mark, a measuring apparatus is disposed at the front of a syringe, which will increase a size thereof Also, manufacturing costs increase due to the addition of a physical quantity measuring apparatus to a disposable syringe.

SUMMARY OF THE INVENTION

An aspect of the present invention provides an apparatus and method for measuring a dose in an injector, which is capable of measuring a dose without modifying the mechanical structure of the injector.

In accordance with one aspect of the present invention, an apparatus for measuring a dose in an injector includes a number sleeve and an injector body. The number sleeve is provided to pass through an injector body and is connected to be spirally movable, and a pattern for dose measurement is formed on an outer periphery of the number sleeve. The injector body includes a sensor for sensing the pattern formed on the number sleeve when the number sleeve performs a spiral movement, and a controller for measuring a dose according to a spiral movement distance of the number sleeve through the sensor.

In accordance with another aspect of the present invention, there is provided a method for measuring a dose in an injector, wherein the injector includes a number sleeve passing through an injector body and having a pattern on an outer periphery thereof in a spiral direction, and the injector body having a sensor for sensing a change in the pattern formed on the number sleeve. The method includes sensing the change in the pattern formed on the number sleeve when the number sleeve performs a spiral movement while passing through the injector body, measuring a spiral movement distance of the number sleeve according to the change in the pattern, and measuring a dose according to the measured spiral movement distance.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, specific details such as detailed configuration and components are merely provided to assist the overall understanding of embodiments of the present invention. Therefore, it should be apparent to those skilled in the art that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Throughout the drawings, the same drawing reference numerals will be understood to refer to the same elements, features and structures. In addition, descriptions of well-known functions and constructions are omitted for the sake of clarity and conciseness.

FIGS. 1A to 1Cillustrate methods for measuring a dose in an injector according to the present invention.

Three methods for measuring a dose in an injector are illustrated inFIGS. 1A to 1C.

Referring toFIG. 1A, a dose is measured by sensing a change in a magnetic field. A number sleeve150is connected to an injector body100and is provided to pass through the injector body100and adjust a dose while performing a straight movement and a spiral movement, and a regular magnetic pattern151for measuring a dose is formed on the outer periphery of the number sleeve150in a spiral direction.

In addition, at least one sensor is provided on the inner periphery of the injector body100to sense a change in the magnetic pattern151of the number sleeve150when the number sleeve150performs a straight movement together with a spiral movement. A spiral movement distance of the number sleeve150is measured according to an output signal of the sensor, and a dose is measured according to the measured spiral movement distance.

Referring toFIG. 1B, a dose is measured by sensing a change in shading. A number sleeve150is provided to pass through an injector body100and adjust a dose while performing a straight movement and a spiral movement, and an optical pattern152for measuring a dose is formed on the outer periphery of the number sleeve150in a spiral direction. The optical pattern152has repeated shaded sections.

In addition, at least one optical encoder410is provided on the inner periphery of the injector body100to sense a change in the optical pattern152of the number sleeve150when the number sleeve150performs a straight movement together with a spiral movement. A spiral movement distance of the number sleeve150is measured according to a sense signal output from the optical encoder410, and a dose is measured according to the measured spiral movement distance.

Referring toFIG. 1C, a dose is measured by sensing a movement distance of a surface image. A number sleeve150is provided to pass through an injector body100and adjust a dose while performing a straight movement and a spiral movement, and an image pattern153having uneven surface roughness is formed on the outer periphery of the number sleeve150.

In addition, an optical tracker is provided on the inner periphery of the injector body100to sense the movement distance of the surface image pattern153having uneven surface roughness on the number sleeve150when the number sleeve150performs a straight movement together with a spiral movement. A spiral movement distance of the number sleeve150is measured by sensing the movement of the surface image through the optical tracker, and a dose is measured according to the measured spiral movement distance.

FIGS. 2A to 2Cillustrate a method for measuring a dose in an injector according to a first embodiment of the present invention, andFIG. 3is a block diagram of the injector shown inFIG. 2.

FIG. 2Aillustrates a structure of an injector that may measure a dose by sensing a change in a magnetic field. A number sleeve150passes through an injector body100and moves straight while performing a spiral movement. A magnetic pattern151is wound around the outer periphery of the number sleeve150in a spiral direction, or a magnetized pattern is formed thereon in a spiral direction. The magnetic pattern151has N poles and S poles that may be formed regularly or continuously.

At least one sensor210, also shown inFIG. 1A, is provided on the inner periphery of the injector body100in parallel with a spiral angle of the number sleeve150, and the sensor210may be a Hall effect sensor or a magnetoresistive sensor.

When the number sleeve150performs a spiral movement while passing through the injection body100, the sensor210senses the change in the magnetic field through the change in the magnetic pattern151and outputs the sense signal. A MicroController Unit (MCU) (hereinafter, a controller)215measures the spiral movement distance of the number sleeve150through the sense signal output from the sensor210, and measures the dose according to the measured spiral movement distance.

FIG. 2Billustrates a cross section of the number sleeve150shown inFIG. 2A. Reference numerals150and151represent the number sleeve body and an adhesive, respectively. Reference numeral152represents the magnetic pattern151made of a rubber magnet or a flexible magnet having a thickness of 200 μm to 300 μm. Reference numeral153represents a polymer cover that is coated on the surface of the magnetic pattern151or can be coated thereon. Characters of the number sleeve150may be expressed on the polymer cover153.

When two sensors A and B are provided, signals output when the change in the magnetic field is sensed through the change in the magnetic pattern are shown inFIG. 2C. A phase of the signal output from the sensor B lags behind a phase of the signal output from the sensor A by 90 degrees.

FIG. 3illustrates the structure of the injector body100shown inFIG. 2A. A battery211supplies power to the components of the injector, and a Power Management Integrated Circuit (PMIC)214manages a power control.

At least one sensor210may be provided in the injector body. When the number sleeve150moves straight while performing the spiral movement, the sensor210senses the change in the magnetic field according to the change in the magnetic pattern151formed on the inner periphery of the number sleeve150, and outputs signals shown inFIG. 2C.

The controller215may include a quadrature decoder216and a memory217, both of which may be separately provided.

The quadrature decoder216divides a magnetic pattern pitch by four times. When N poles and S poles in the magnetic pattern of the number sleeve150are continuously magnetized, 2-mm pitch may be realized. Theoretically, the 0.5-mm spiral movement distance measurement can be achieved by the use of the quadrature decoder216. Since 0.5-mm resolution makes it possible to divide 2 mm corresponding to 1 unit of the general number sleeve by four times, the dose measurement corresponding to the spiral movement distance may be more accurate.

The memory217stores the measured dose and the date and time of injection, and stores the dose corresponding to the spiral movement distance.

In addition, the controller215may extract from the memory217the dose corresponding to the spiral movement distance measured according to the change in the magnetic field, and display the extracted dose and the date and time of injection on a display222or transmit them to an external host device300automatically or by a user's selection.

A push injection button212is provided for starting the operation of the injector, and I/O buttons213are provided for displaying the dose and the date and time of injection, which are stored in the memory217, on the display222.

A Radio Frequency (RF) unit219may transmit the dose and the date and time of injection, which are stored in the memory217, to an external device, such as a host device300of a medical center or hospital, by wireless under the control of the controller215.

A Universal Serial Bus (USB)220is provided for a serial connection, and is connected to a USB port of the external host device300and may transmit the dose and the date and time of injection, which are stored in the memory217, to the external device, such as the host device300of the medical center or hospital, by cable under the control of the controller215.

A Liquid Crystal Display (LCD) controller221controls an LCD222, which displays the measured dose and the date and time of injection under the control of the LCD controller221.

The operation of measuring the dose in the injector shown inFIGS. 2A and 3will be described below. If a user presses the push injection button212to start the operation of the injector, the number sleeve150performs a spiral movement and a straight movement while passing through the injector body100. The sensor210of the injector body100senses the change in the magnetic field according to the change in the magnetic pattern151of the number sleeve150, and outputs the sensed signal to the controller215.

Using the sensed signal output from the sensor210, the controller215measures the spiral movement distance of the number sleeve150, extracts the dose corresponding to the measured spiral movement distance from the memory217, and displays the extracted dose on the display222or transmits the extracted dose to the external host device300.

The first embodiment of the present invention aims at adjusting the dose by measuring the dose using the magnetic pattern formed on the number sleeve150that performs the spiral movement and the straight movement. Therefore, if the number sleeve150moves straight while performing the spiral movement, the dose is measured and is simultaneously adjusted. Thereafter, if the user presses the button disposed at the end of the injector, the screw provided inside the number sleeve150is connected to the clutch. Accordingly, the number sleeve150moves the injector piston forward by the spiral movement, and the dose is thereby injected into the user.

FIGS. 4A to 4Cillustrate a method for measuring a dose in an injector according to a second embodiment of the present invention, andFIG. 5is a block diagram of the injector shown inFIG. 4A.

FIG. 4Aillustrates a structure of an injector that may measure a dose by sensing a change in shading. A number sleeve150passes through an injector body100and moves straight while performing a spiral movement. A reflective optical pattern152is formed on the outer periphery of the number sleeve150in a spiral direction. The reflective optical pattern152is formed by regular shading repetition.

FIG. 4Billustrates the optical pattern formed on the outer periphery of the number sleeve150by regular shading repetition.

At least one optical encoder410, also shown inFIG. 4A, is provided on the inner periphery of the injector body100in parallel with a spiral angle of the number sleeve150, and the optical encoder410includes a light emitting element and a light receiving element. Instead of the optical encoder, any type of sensors may be used as long as they can sense a change in shading. For example, a sensor having a combination of a photodiode (PD) and a light emitting diode (LED) may be used as the optical encoder410.

When the number sleeve150performs a spiral movement while passing through the injection body100, the optical encoder410senses the change in the shading through the change in the optical pattern152and outputs the sense signal. A microcontroller unit (MCU) (hereinafter, referred to as a controller)415measures a spiral movement distance of the number sleeve150through an output signal of the optical encoder410, and measures a dose using the measured spiral movement distance.

When two optical encoders A and B are provided, signals output when the change in the shading is sensed through the change in the optical pattern are shown inFIG. 4C. A phase of the signal output from the optical encoder B lags behind a phase of the signal output from the optical encoder A by 90 degrees.

FIG. 5illustrates the structure of the injector body100shown inFIG. 4A. A battery411supplies power to the components of the injector, and a PMIC414manages a power control.

At least one optical encoder410may be provided in the injector body100, and the optical encoder410includes a light emitting element and a light receiving element. In addition, when the number sleeve150moves straight while performing the spiral movement, the optical encoder410senses the change in the magnetic field according to the change in the optical pattern formed on the inner periphery of the number sleeve150, and outputs signals shown inFIG. 4C.

The controller415may include a quadrature decoder416and a memory417, both of which may be separately provided.

The quadrature decoder416divides a magnetic pattern pitch by four times. When a 150 line-per-inch (lpi) reflective optical line pattern is used, 42-μm spiral movement distance measurement can be achieved through the quadrature decoder416.

The memory417stores the measured dose and the date and time of injection, and stores the dose corresponding to the spiral movement distance.

In addition, the controller415may extract from the memory417the dose corresponding to the spiral movement distance measured according to the change in the shading, and display the extracted dose and the date and time of injection on a display422or transmit them to an external host device300automatically or by a user's selection.

A push injection button412is provided for starting the operation of the injector, and I/O buttons413are provided for displaying the dose and the date and time of injection, which are stored in the memory417, on the display422.

An RF unit419may wirelessly transmit the dose and the date and time of injection, which are stored in the memory417, to the external device, such as the host device300of the medical center or hospital, under the control of the controller415.

A USB420is provided for a serial connection, and is connected to a USB port of the external host device300and may transmit the dose and the date and time of injection, which are stored in the memory417, to the external device, such as the host device300of the medical center or hospital, by cable under the control of the controller415.

An LCD controller421controls an LCD422, and the LCD422displays the measured dose and the date and time of injection under the control of the LCD controller421.

The operation of measuring the dose in the injector shown inFIGS. 4A and 5will be described below. If a user presses the push injection button412to start the operation of the injector, the number sleeve150performs a spiral movement and a straight movement while passing through the injector body100. The optical encoder410of the injector body100senses the change in the shading according to the change in the optical pattern152of the number sleeve150, and outputs a sense signal to the controller415.

Using the sense signal output from the optical encoder410, the controller415measures the spiral movement distance of the number sleeve150, extracts the dose corresponding to the measured spiral movement distance from the memory417, and displays the extracted dose on the display422or transmits the extracted dose to the external host device300.

The second embodiment of the present invention aims at adjusting the dose by measuring the dose using the optical pattern152formed on the number sleeve150that performs the spiral movement and the straight movement. Therefore, if the number sleeve150moves straight while performing the spiral movement, the dose is measured and is simultaneously adjusted. Thereafter, if the user presses the button disposed at the end of the injector, a screw provided inside the number sleeve150is connected to a clutch. Accordingly, the number sleeve150moves the injector piston forward by the spiral movement, and the dose is thereby injected into the user.

FIGS. 6A and 6Billustrate a method for measuring a dose in an injector according to a third embodiment of the present invention, andFIG. 7is a block diagram of the injector shown inFIG. 6A.FIG. 8illustrates results obtained by measuring a movement distance of a number sleeve shown inFIG. 6A.

FIG. 6Aillustrates a structure of an injector that may measure a dose through a movement detection of a surface image. A number sleeve150passes through an injector body100and moves straight while performing a spiral movement. An image pattern153having an uneven surface roughness is formed on the outer periphery of the number sleeve150.

The surface roughness of the image pattern153has an irregular and random shape larger than 850 nm, which is used as a light source of an optical system, so as to obtain the formed image through the optical system.

An optical tracker610is provided on the inner periphery of the injector body100in parallel with a spiral angle of the number sleeve150.

When the number sleeve150performs a spiral movement while passing through the injection body100, the optical tracker610forms the surface image, senses the movement of the surface image through the change in the pattern of the formed surface image, and outputs the sensed movement to a microcontroller unit (MCU) (hereinafter, controller)615of the injector body100, which measures a spiral movement distance of the number sleeve150through an algorithm, and measures a dose according to the measured spiral movement distance.

FIG. 6Billustrates the operation of forming the surface image using the light source Light Emitting Diode (LED/LD) of the optical tracker610and sensing the formed surface image using an image sensor of the optical tracker610.

FIG. 7illustrates the structure of the injector body100shown inFIG. 6A. A battery611supplies power to the components of the injector, and a PMIC614manages a power control.

The optical tracker610includes a light source LED/LD, an image sensor, and a moving vector estimator. When the number sleeve150performs a spiral movement while passing through the injector body100, the light source forms the surface image as shown inFIG. 6B, and the image sensor senses the formed surface image. The moving vector estimator senses the movement distance of the surface image through the change in the pattern of the formed surface image, and outputs the sensed movement distance to the controller615.

Instead of the optical tracker610, an optical joystick or an optical mouse module may be used to measure the movement distance of the surface image.

The controller615may include a memory617, which may be separately provided.

The memory617stores the measured dose, the date and time of injection, and the dose corresponding to the spiral movement distance, and stores an algorithm for measuring the spiral movement distance of the number sleeve150according to the movement distance of the surface image.

The controller615may measure a 36-μm spiral movement distance through a 1:1 image system.

When the movement distance of the surface image is outputted from the optical tracker610, the controller615measures the spiral movement distance of the number sleeve150corresponding to the movement distance of the surface image through the algorithm stored in the memory617, and measures the dose according to the measured spiral movement distance.

Moreover, the controller615may extract from the memory617the dose corresponding to the spiral movement distance measured according to the movement distance of the surface image, and display the extracted dose and the date and time of injection on a display622or transmit them to the external host device300automatically or by a user's selection.

A push injection button612is provided for starting the operation of the injector, and I/O buttons613are provided for displaying the dose and the date and time of injection, which are stored in the memory617, on the display622.

An RF unit619may wirelessly transmit the dose and the date and time of injection, which are stored in the memory617, to an external device, such as a host device300of a medical center or hospital, under the control of the controller615.

A USB620is provided for a serial connection, and is connected to a USB port of the external host device300and may transmit the dose and the date and time of injection, which are stored in the memory617, to the external device, such as the host device300of the medical center or hospital, by cable under the control of the controller615.

An LCD controller621controls an LCD622, which displays the measured dose and the date and time of injection under the control of the LCD controller621.

The operation of measuring the dose in the injector shown inFIGS. 6A and 7will be described below. If a user presses the push injection button612to start the operation of the injector, the number sleeve150performs a spiral movement and a straight movement while passing through the injector body100. The optical tracker610of the injector body100senses the movement distance of the surface image through the change in the image pattern153of the number sleeve150, and outputs the sensed movement distance to the controller615.

Using the movement distance of the surface image, which is output from the optical tracker610, the controller615measures the spiral movement distance of the number sleeve150, extracts the dose corresponding to the measured spiral movement distance from the memory617, and displays the extracted dose on the display622or transmits the extracted dose to the external host device300.

The third embodiment of the present invention aims at adjusting the dose by measuring the dose using the optical pattern formed on the number sleeve150that performs the spiral movement and the straight movement. Therefore, if the number sleeve150moves straight while performing the spiral movement, the dose is measured and is simultaneously adjusted. Thereafter, if the user presses the button disposed at the end of the injector, a screw provided inside the number sleeve150is connected to a clutch. Accordingly, the number sleeve150moves an injector piston forward by the spiral movement, and the dose is thereby injected into the user.

FIG. 8illustrates results obtained by measuring the movement distance of the surface image according to the spiral movement and the straight movement of the number sleeve shown inFIG. 6A.

As is apparent from the foregoing description, according to embodiments of the present invention, provided is an apparatus and method for conveniently measuring the dose in the injector. Since the number sleeve of the injector, the stability and reliability of which have already been verified, is used for adjusting the dose without modifying the mechanical structure thereof, the limit of the dose measurement may be overcome and the mass production and production cost reduction may be achieved.