Abstract:
Disclosed is a portable automatic insulin syringe device adapted to enable an injection of liquid medicine for a prolonged time, including a syringe pump having a pump housing, further including a blood sugar measuring unit mounted at one side of the pump housing and adapted to measure a blood sugar level of a user, a control unit for controlling the blood sugar measuring unit and the syringe pump, and a display unit for simultaneously displaying the quantity of insulin dispensed to a user and the blood sugar level measured by the blood sugar measuring unit.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a portable automatic insulin syringe device capable of measuring and displaying the quantity of insulin dispensed to the user and the blood sugar level of the user, while having an automatic insulin injecting function. In particular, the present invention provides a portable automatic insulin syringe device which is adapted to automatically dispense insulin to the user for a prolonged time, and includes a blood sugar measuring unit mounted in a syringe device housing and adapted to measure the blood sugar level of the user, and a control unit adapted to receive a measured value from the blood sugar measuring unit, thereby performing a control for displaying the measured value along with the quantity of insulin dispensed to the user, so that the syringe device can measure the blood sugar level of the user. 
     2. Description of the Related Art 
     Diabetes is known to affect more than one hundred million individuals worldwide at the present time, assuming there are about six billion people worldwide. For instance, in Korea, it is believed that diabetes affects about two million individuals. It is also estimated that 10% of patients with internal diseases suffer from diabetes in Korea. There is no cure for diabetes although it can be controlled. If a diabetic patient fails to control his disease, he may develop complications, thereby endangering his life. For instance, in Korea, the death rate due to diabetes is increasing gradually. In 1990, 11.5 individuals per one hundred thousand population died of the disease. Thus, diabetes is known as a fatal disease. 
     Diabetes is a disease symptomized by an increase in blood sugar levels exceeding 140 mg/dl on an empty stomach, or 200 mg/dl 2 hours after a meal. The cause of such increased in blood sugar levels is not yet clearly known. An abnormality in the production of insulin, serving to promote assimilation of sugar, is the only cause known heretofore. Such an abnormality may be an insulin deficiency, caused by an insufficient quantity of insulin secreted by the β-cells of the pancreas. Otherwise, an increase in blood sugar level is caused by a degradation in the function of insulin, occurring for unknown reasons, thereby resulting in an insufficient assimilation of blood sugar, even though a desired quantity of insulin is normally secreted by the β-cells of the pancreas. Such a degradation in the function of insulin is called “insulin resistance”. Diabetes resulting from an absolute insulin deficiency is called an “insulin-dependent diabetes” whereas diabetes resulting from an insufficient function of insulin in spite of a sufficient secretion of insulin is called a “noninsulin-dependent diabetes”. Recently, the possibility of an intermediate type between the insulin-dependent diabetes and non-insulin-dependent diabetes has also been discussed. It is difficult to accurately determine whether a diabetic patient is insulin-dependent or non-insulin-dependent. Known methods for treatment of diabetes are classified into dietary treatment, exercise treatment, medicinal therapy, and insulin injections. A pancreas transplant is also a possible option. 
     Although insulin injection is a treatment used for patients with insulin-dependent diabetes, it may also be effective for patients with non-insulin-dependent diabetes. In accordance with the insulin injection method, it is normal that insulin is dispensed to a diabetic patient one or two times daily by injection. The quantity of insulin secreted in the human body is irregular in that an increased quantity of insulin is secreted three times daily, before and after respective mealtimes, while a reduced quantity of insulin is secreted at other times. For this reason, insulin is dispensed at a steady rate in accordance with the above mentioned insulin injection. This results in a high blood sugar level for a certain period of time after every mealtime because of an insulin deficiency, while resulting in a low blood sugar level at night because of an excessive secretion of insulin. That is, the above mentioned insulin injection method involves an abnormal dispensation of insulin, thereby causing an abnormality of the body. The reason why conventional insulin injection methods cannot contribute to the prevention of any complications from diabetes is because they cannot control the dispensation of insulin in accordance with a variation in the quantity of endogenous insulin naturally secreted in the body of a healthy person. To this end, improved treatment methods have been proposed. One method is to use an insulin pump (namely, a mechanical artificial pancreas) adapted to control the quantity of dispensed insulin using a computer in such a fashion that the dispensation of insulin approximates the secretion of insulin in the body of a healthy person. Another method is a surgical operation method for transplanting the β-cells of the pancreas. In accordance with this pancreas transplant method, the β-cells of the pancreas of a healthy person are transplanted to a diabetic patient so that the diabetic patient normally secretes insulin to normally control his blood sugar level. However, the pancreas transplant method involves immunological rejection complications and other associated problems. This pancreas transplant method was studied in U.S.A. from 1974 and practiced by Professor Temberane at Yale University in U.S.A. from 1979. 
     Automatic syringe devices, which enable an injection of liquid medicine for a prolonged time, are well known. Such automatic syringe devices are called “insulin pumps”, “insulin syringe devices”, or “automatic insulin syringe devices”. Typically, known automatic syringe devices have a configuration in which a pushing means for pushing a syringe piston is coupled to a housing receiving an injection syringe. For example, such automatic syringe devices are disclosed in Japanese Utility Model Laid-open Publication No. Sho. 52-3292 and U.S. Pat. No. 4,417,889. The syringe device disclosed in Japanese Utility Model Laid-open Publication No. Sho. 52-3292 has inconvenience in its carriage because it has an injector mounted outside a basic case, thereby requiring a double case structure. In order to solve such a disadvantage, an automatic syringe device requiring no double case structure has been proposed, as in the above mentioned U.S. Pat. No. 4,417,889.  FIGS. 1 and 2  illustrate a control circuit and a structure of the automatic syringe device disclosed in U.S. Pat. No. 4,417,889, respectively. Referring to  FIG. 1 , the output of an oscillator A 1  is coupled to a timer A 2  which is, in turn, coupled at its output to a digital comparator A 3 . The digital comparator A 3  also receives an output from a fixed number switch A 4 . The output of the digital comparator A 3  is connected to a counter A 6  and an R/S flip-flop A 9 . Another oscillator A 5  is also provided which has an output coupled to counters A 6  and A 13 , and AND gates A 10  and A 11 . The flip-flop A 9  is reset by an output from a digital comparator A 7 . Another R/S flip-flop A 16  is also provided which is reset by an output from a digital comparator A 14  coupled to the counter A 13 . A control unit A 17  is also coupled to the counter A 13 . The control unit A 17  serves to activate the counter A 13  in accordance with an operation of a manual infusion switch A 12 . The control unit A 17  applies its output to the counters A 13  and A 16 . The output from the control unit A 17  is also sent to a counter A 21 . The output of the counter A 21  is coupled to a digital comparator A 22  which is, in turn, coupled to a step motor driver A 19  for driving a step motor A 20 . The output of the flip-flop A 16  is coupled to one input of the AND gate A 11 , which is also coupled at the other input thereof to the oscillator A 5 . The output of the AND gate A 11  is coupled to one input of an OR gate A 18 . Fixed number switches A 15  and A 25  are connected to the digital comparators A 14  and A 22 , respectively. Each of the fixed number switches A 4 , A 8 , A 15 , and A 25  has five protruding insert bars and serves to provide a reference value for an associated one of the digital comparators A 3 , A 7 , A 14 , and A 22 . A light source A 24  and a photo sensor A 23  are coupled to the counter A 21  in order to provide sensing results thereof to the counter A 21 , respectively. Referring to  FIGS. 2 and 3 , the arrangements of the light source A 24  and photo sensor A 23  are illustrated. As shown in  FIGS. 2 and 3 , the light source A 24  and photo sensor A 23  are arranged in such a fashion that they face each other while being vertically spaced from each other. A gear plate, which is included in a gear mechanism G, is interposed between the light source A 24  and photo sensor A 23 . The gear plate has a plurality of through holes A 26  uniformly spaced from one another in a circumferential direction, as shown in FIG.  3 . The gear plate is fixedly fitted around a gear shaft A 27  having a screw portion. A piston plate A 28  is threadedly coupled to the gear shaft A 27  in the form of a nut in such a fashion that it slides along the screw portion of the gear shaft A 27  when the gear shaft A 27  rotates. The rotation of the gear shaft A 27  is carried out by a drive force from the motor A 20  transmitted via the gear mechanism G. The driving of a motor M (corresponding to the motor A 20  in  FIG. 1 ) is controlled by the operations of the counter A 21 , digital comparator A 22 , switch A 25 , and motor drive A 19 . The above mentioned elements of the syringe device are received in a housing, as shown in FIG.  2 . In particular, the light source A 24  and photo sensor A 23  are fixedly mounted at an upper portion of the housing by means of a bracket fixed to the housing. In this syringe device, a liquid medicine, such as insulin, contained in a syringe I is outwardly injected through an injection needle N connected to the syringe I, by a sliding movement of the piston plate A 28 . In such a syringe device, however, the housing and syringe I thereof are exposed to the atmosphere. As a result, moisture and water are likely to penetrate into the syringe device. For this reason, there is inconvenience in that if the user desires to take a shower while the syringe is in place, then the housing should be contained in a separate sealing case. 
     In order to solve such a problem, a sealable syringe device has been proposed by the applicant. Such a sealable syringe device is illustrated in  FIG. 4 , which is a front view. Referring to  FIG. 4 , the syringe device includes a cover  10  sealably coupled to the upper end of a housing  20 , and a bottom cover  40  sealably coupled to the lower end of the housing  20 . A connector  2 , to which a feeding tube  1  is integrally connected, is threadedly coupled to the cover  10 . The connector  2  communicates with a syringe  21  received in the housing  20 . A piston  22  is slidably fitted in the syringe  21 . A liquid medicine to be injected is contained in the syringe  21 . A power transmission means  30  is mounted on the bottom surface of the housing  20 . The power transmission means  30  has a rotating shaft  31  to which a disc type pushing means  50  is threadedly coupled. The disc type pushing means  50  moves vertically by a rotation of the rotating shaft  31 , thereby vertically moving the piston  22 . 
     Referring to  FIG. 5 , which is a plan view of  FIG. 4 , the cover  10 , to which the connector  2  connected with the feeding tube  1  is connected, is arranged on the left portion of the upper surface of the housing  20 . A battery cover  24  is arranged on the right portion of the upper surface of the housing  20 . 
       FIG. 6  is a cross-sectional view taken along the line A—A of FIG.  5 . As shown in  FIG. 6 , the cover  10  is centrally provided with a threaded hole  11  in which the connector  2  is threadedly fitted at its lower end. The threaded hole  11  has threads  11 - 1 . The connector is formed, at its lower end, with threads  2 - 15  to be threadedly coupled with the threads  11 - 1  of the threaded hole  11 . The cover  10  is also provided at its lower end with a bolt portion  12  threadedly fitted in the upper end of the housing  20 . A packing  13  is fitted around the bolt portion  12  of the cover  10  between the lower end of the cover  10  and the upper end of the housing  20 . A syringe receiving chamber  23  is defined in the interior of the housing  20 . The pushing means  50  is fitted in the lower end of the housing  20  in such a fashion that it slides vertically in the housing  20 . The housing  20  is also formed at its inner surface with a vertical pushing means guide groove  25  adapted to guide a vertical movement of the pushing means  50  and vertical piston guide grooves  27  adapted to guide a vertical movement of the piston  22 . 
       FIG. 7  shows a detailed configuration of the power transmission means  30  mounted on the bottom surface of the housing  20  and a detailed configuration of the pushing means  50  threadedly coupled to the rotating shaft  31  of the power transmission means  30 . As shown in  FIG. 7 , the pushing means  50  includes a lower disc  54  threadedly coupled to the rotating shaft  31  in such a fashion that it slides vertically along the rotating shaft  31 . The lower disc  54  is provided at its periphery with a guide protrusion  51  engaged in the guide groove  25  of the housing  20  and adapted to guide the vertical movement of the lower disc  54 . The pushing means  50  also includes an upper disc  55  integrally formed with the lower disc  54 . The upper disc  55  is provided at its periphery with an engagement means  52 . The upper disc  55  is fitted in a sleeve plate  26  ( FIG. 8 ) fixed to the lower end of the piston  22  in such a manner that its engagement means  52  engages with a mating engagement means formed on the inner peripheral surface of the sleeve plate  26 . The sleeve plate  26  is also provided at its outer peripheral surface with protrusions engaging with the guide grooves  27  respectively. The power transmission means  30  includes a reduction mechanism  33  for transmitting the rotational force of a motor (not shown) to the rotating shaft  31  in a speed-reduced manner. 
     In order to use the syringe device having the above mentioned configuration, the piston  22 , which is in a state separated from the housing  20 , is first fitted in the syringe  21 , which is also in a state separated from the housing  20 , in such a manner that it is completely inserted into the syringe  21 . In this state, a disposable injection needle (not shown) is fitted onto the tip  21 - 1  of the syringe  21 . Thereafter, the injection needle is penetrated into the interior of a phial through the plug of the phial. In this state, the piston  22  is pulled to suck a liquid medicine (for example, insulin) contained in the phial into the syringe  21 . 
     The piston  22 , which is in a state fitted in the syringe  21  containing the liquid medicine, is then inserted into the syringe receiving chamber  23  of the housing  20  in such a manner that it is seated on the pushing means  50 . Subsequently, the cover  10  is threadedly coupled to the upper end of the syringe receiving chamber  23 . The connector  2  is then threadedly fastened to the cover  10 . As the connector  2  is threadedly fastened to the cover  10 , it is fitted onto the syringe tip  21 - 1 . Thus, the syringe  21  is maintained in a sealed state in the housing  20 . When the motor (not shown) is operated under the above condition, the pushing means  50  moves upwardly, thereby upwardly pushing the piston  22 . As a result, the liquid medicine contained in the syringe  21  is outwardly injected from the syringe  21 . At this time, the upward movement of the pushing means  50  is accurately carried out because its guide protrusion  51  engages with the guide groove  25 . Since respective protrusions of the sleeve plate  26  slide along the piston guide grooves  27  shown in  FIG. 6 , the upward movement of the piston  22  is also accurately carried out. 
     Meanwhile,  FIG. 9  illustrates an example of a conventional injection needle unit for portable automatic syringe devices enabling a prolonged injection of a liquid medicine. As shown in  FIG. 9 , the injection needle unit includes a feeding tube  1 , a “-” shaped straight injection needle member (called a “straight butterfly-shaped injection needle”)  3  connected to one end of the feeding tube  1 , and a connector  2  connected to a connector portion  20 - 5  of the housing  20 . 
     In order to use such an injection needle unit, the user himself angularly penetrates the straight butterfly-shaped injection needle member  3  into his subcutaneous tissue while observing the penetration of the injection needle member  3  with the naked eye. The reason why the user observes the penetration of the injection needle member  3  with the naked eye is because the injection needle member  3  has a straight shape. However, such an observation is very uncomfortable. The straight butterfly-shaped injection needle member  3  is also likely to move within the subcutaneous tissue of the user because it penetrates the subcutaneous tissue of the user at an angle. In this case, the subcutaneous tissue may be damaged. In severe cases, blood may flow out of the subcutaneous tissue. The user may also feel a severe pain. 
     As mentioned above, the conventional injection needle unit has a drawback in that it is difficult to smoothly inject insulin because the injection needle member  3 , which penetrates the subcutaneous tissue of the user at an angle, may be easily blocked at its tip by the subcutaneous tissue. To this end, the feeding tube of such a conventional injection needle unit inevitably has an increased diameter. However, such a feeding tube having an increased diameter results in a possibility of an excessive insulin injection. In addition, this may result in wastage of expensive insulin. For instance, where it is desired to inject insulin into the user using an automatic syringe device equipped with the above mentioned injection needle unit, it is necessary to completely vent air existing in the feeding tube  1  and injection needle member  3  before penetrating the injection needle member  3  into the subcutaneous tissue of the user. To this end, insulin, which is contained in the syringe device, is outwardly discharged through the feeding tube  1  and injection needle member  3 , thereby venting air. In this case, a large amount of insulin is wasted where the conventional injection needle unit having the diameter-increased feeding tube is used. 
     In order to solve this problem, an injection needle unit has been proposed which has an L-shaped injection needle. Such an injection needle unit is illustrated in  FIGS. 10 and 11 , respectively. As shown in  FIGS. 10 and 11 , the injection needle unit includes a feeding tube  1 , an injection needle member  3  connected to one end of the feeding tube  1 , and a connector  2  connected to the other end of the feeding tube  1 . 
     In the case of the injection needle unit shown in  FIGS. 10 and 11 , the injection needle member  3  has an injection needle  3 - 11  having an L-shaped structure shown in FIG.  12 . This injection needle  3 - 11  has a first portion, namely, a horizontal portion, fitted in a connecting rib  3 - 12  integrally formed with one end of the feeding tube  1 , and a second portion, namely, a vertical portion, provided with a needle tip. The injection needle  3 - 11  is provided with a curved portion  3 - 13  at its horizontal portion fitted in the connecting rib  3 - 12 , as shown in  FIG. 11. A  pressing member  3 - 14  is integrally formed with the connecting rib  3 - 12  in such a fashion that the injection needle  3 - 11  protrudes perpendicularly from the pressing member  3 - 14 . The pressing member  3 - 14  is pressed against the skin of the user upon penetrating the injection needle member  3  into the subcutaneous tissue. A bacterial infection prevention member  3 - 14 - 1 , which is made of a sterile nonwoven fabric, is attached to the surface of the pressing member  3 - 14  which comes into contact with the skin of the user upon penetrating the injection needle unit  3  into the subcutaneous tissue. The connector  2 , which is connected to the other end of the feeding tube  1 , has a male thread  2 - 15 . The connector  2  is protected by a protection cap  2 - 17  which has a female thread  2 - 16  threadedly coupled to the male thread  2 - 15  of the connector  2 . In use, the connector  2  is threadedly coupled to a connector portion  20 - 5  of a housing  20  included in an automatic insulin syringe device. The connector portion  20 - 5  of the housing  20  has a female thread  20 - 5   a  threadedly coupled to the male thread  2 - 15  of the connector  2 . In  FIG. 10 , the reference numeral “ 3 - 18 ” denotes a needle protection cap. 
     Where it is desired to inject insulin contained in the automatic insulin syringe device using the above mentioned injection needle unit, the protection cap  2 - 17  is first separated from the connector  2 , which is, in turn, threadedly coupled to the connector portion  20 - 5  of the housing  20 . Thereafter, the needle protection cap  3 - 18  is separated from the injection needle  3 - 11 . The user then penetrates the injection needle  3 - 11  into the subcutaneous tissue while pressing the pressing member  3 - 14  against the skin by hand. At this time, the injection needle  3 - 11  penetrates vertically into the subcutaneous tissue of the user because it has an “L” shape. Accordingly, the user can carry out the penetration of the injection needle  3 - 11  instantaneously without having to observe the penetration with the naked eye. Therefore, the user feels little pain upon penetrating the injection-needle  3 - 11  into the subcutaneous tissue. By virtue of such a configuration of the injection needle unit  3 , the automatic insulin syringe device can be conveniently used, as shown in FIG.  13 . Since the injection needle  3 - 11  penetrates vertically into the subcutaneous tissue of the user by virtue of its “L” shape, there does not occur any phenomenon that the injection needle  3 - 11  is blocked at its tip by the subcutaneous tissue of the user. Thus, the injection of insulin is smoothly carried out. Accordingly, the feeding tube can have a reduced diameter and an increased length. Since the feeding tube  1  has a reduced diameter, it is possible to minimize the wastage of insulin occurring upon venting air existing in the feeding tube  1  and injection needle  3 - 11  and to reduce the manufacturing costs. Since the feeding tube  1  also has an increased length, it is possible to extend the range of the applied positions of the injection needle  3 - 11  on the body of the user. Accordingly, it is possible to achieve convenience in use. Since the bacterial infection prevention member  3 - 14 - 1 , which is made of a sterile nonwoven fabric, is attached to the pressing member  3 - 14 , it is possible to prevent the pressing member  3 - 14  from coming into direct contact with the skin of the user upon penetrating the injection needle unit  3  into the subcutaneous tissue. Accordingly, it is possible to prevent the user from being infected. Since the injection needle  3 - 11  penetrates vertically into the subcutaneous tissue of the user by virtue of its “L” shape, as mentioned above, it hardly moves in the subcutaneous tissue, even when an external force is applied thereto. Accordingly, there is no damage caused to the subcutaneous tissue. Of course, there does not occur any phenomenon that blood flows out of the subcutaneous tissue. The user also does not feel any pain. 
     In the case of the injection needle unit mentioned above, the needle protection cap  3 - 18  is used which has a configuration as shown in FIG.  14 . The needle protection cap  3 - 18  has a needle tip receiving hole including a smaller diameter portion  3 - 18 - 1  with the same diameter as the injection needle  3 - 11  and a larger diameter portion  3 - 18 - 2  with a diameter larger than the diameter of the injection needle  3 - 11 . Since the needle protection cap  3 - 18  has such a configuration, there is a problem in that it is difficult to separate the needle protection cap  3 - 18  from the injection needle  3 - 11  because of the small diameter of the smaller diameter portion  3 - 18 - 1 . As a result, the injection needle  3 - 11  may be damaged. Since the smaller diameter portion  3 - 18 - 1  has a small diameter, a capillary phenomenon may occur between the inner surface of the needle protection cap  3 - 18  and the outer surface of the injection needle  3 - 11  when the liquid medicine is outwardly discharged from the injection needle  3 - 11  to vent air existing in the feeding tube  1  and injection needle  3 - 11 . In this case, a part of the discharged liquid medicine is absorbed in the bacterial infection prevention member  3 - 14 - 1 , thereby causing the user to be uncomfortable. The injection needle  3 - 11  has a sharply bent portion  3 - 11 - 1  between the vertical and horizontal portions thereof due to its “L”-shaped structure. This sharply bent portion  3 - 11 - 1  of the injection needle  3 - 11  may be subjected to excessive stress when the user moves excessively during injection. For instance, when the needle tip of the injection needle  3 - 11  moves from a position indicated by the solid line of  FIG. 15  to a position indicated by the phantom line of  FIG. 15  as the user exercises or conducts hard work, or due to other reasons, the sharply bent portion  3 - 11 - 1  of the injection needle  3 - 11  may be subjected to excessive stress. In this case, the injection needle  3 - 11  may be broken. For this reason, the reliability of the above mentioned injection needle unit is degraded. 
     In order to solve such a problem, a portable automatic syringe device has been proposed which has a configuration including a separable rotating shaft adapted to provide a drive force to a piston included in the automatic syringe device so that the rotating shaft can be separated, along with the piston, from a housing of the syringe device upon re-filling a syringe of the syringe device with a liquid medicine, and set in position in the housing, after the re-filling of the liquid medicine, while observing the setting operation with the naked eye.  FIG. 16  is a perspective view illustrating an example of such a portable automatic syringe device. As shown in  FIG. 16 , the syringe device includes a housing  120 , a syringe  21  separately received in the housing  120 , a piston  122  slidably fitted in the syringe  21  and separately received in the housing  120 , a piston pushing means  150  received in the housing  120  and adapted to vertically move the piston  122 , a power transmission means  130  received in the housing  120  and adapted to generate a drive force, and a rotating shaft  131  received in the housing  120  and adapted to drive the piston pushing means  150  by the drive force transmitted from the power transmission means  130 . The syringe device also includes an injection needle unit (in  FIG. 16 , only its feeding tube  1  and connector  2  are shown). The injection needle unit is connected to the housing  120  by means of a cover  110  which is sealably coupled to the upper end of the housing  120  at one side of the housing  120 . A control button unit  123  is also installed on the housing  120 . The control button unit  123  is electrically connected to a control circuit (not shown) installed in the housing  120  to control the power transmission means  130 . A display  124  such as an LCD is also installed on the housing  120  in order to display the operating state of the syringe device. At the other side of the housing  120 , a battery cover  125  is separately coupled to the upper end of the housing  120  in order to carry a battery in the housing  120 . A reset button  121  is also installed on the housing  120  to generate a reset signal for the control circuit. In  FIG. 16 , the reference numeral “ 140 ” is a bottom cover. 
     Referring to  FIG. 17 , which is a plan view of  FIG. 16 , the cover  110  and battery cover  125  are arranged at opposite sides of the upper wall of the housing  120 , respectively. The reset button  121  is arranged on the upper wall of the housing  120  between the covers  110  and  125 . 
       FIG. 18  is a plan view similar to  FIG. 17 , but without the cover  110 .  FIG. 18  illustrates the inner construction of the housing  120  in which the piston  122  and piston pushing means  150  are received.  FIG. 19  is a cross-sectional view taken along the line B—B of FIG.  18 . As shown in  FIG. 19 , the housing  120  has a syringe receiving chamber  126  defined in the interior of the housing  120 . At the lower end of the syringe receiving chamber  126 , the housing  120  has a hollow support portion in which a coupling member  132  coupled to the power transmission means  130  is rotatably fitted. The housing  120  is also formed, at its inner surface defining the syringe receiving chamber  126 , with a vertical pushing means guide groove  25  adapted to guide a vertical movement of the pushing means  150  and vertical piston guide grooves  27  adapted to guide a vertical movement of the piston  122 . 
       FIG. 20  is an enlarged perspective view illustrating the configuration of the coupling member  132  to which the rotating shaft  131  is coupled. As mentioned above, the coupling member  132  is rotatably fitted in the hollow support portion of the housing  120  at the lower end of the syringe receiving chamber  126 . As shown in  FIG. 20 , the coupling member  132  has a cross groove  132 - 1  in which a horizontal engaging pin  133  coupled to the lower end of the rotating shaft  131  is separately engaged. A gear  132 - 3  is also integrally formed with the coupling member  132 . The gear  132 - 3  engages with an output gear of the power transmission means  130 . Both ends of the engaging pin  133  are protruded from opposite sides of the lower end of the rotating shaft  131 , respectively. By such a configuration, the coupling member  132  rotates by a drive force transmitted from the power transmission means  130  via the gear  132 - 3 , thereby causing the rotating shaft  131  to rotate. 
       FIG. 21  is an exploded perspective view illustrating the rotating shaft  131 , piston pushing means  150 , piston  122 , and syringe  21  separated from one another.  FIG. 22  is a cross-sectional view illustrating the coupled state of the elements of FIG.  21 . As shown in  FIGS. 21 and 22 , the rotating shaft  131  has a screw extending throughout the length thereof. A cap type head  131 - 1  is threadedly coupled to the upper end of the rotating shaft  131 . The piston pushing means  150  is threadedly coupled to the rotating shaft  131  in such a fashion that it moves vertically along the rotating shaft  131 . The piston pushing means  150  includes a push plate  154  threadedly coupled to the rotating shaft  131  in the form of a nut in such a fashion that it slides vertically along the rotating shaft  131 . The push plate  154  is provided at its periphery with a radially-extending guide protrusion  151  engaged in the guide groove  25  of the housing  120  and adapted to guide the vertical movement of the push plate  154 . The push plate  154  is also provided at its upper end with engaging protrusions  151 - 1 . The piston pushing means  150  also includes a fitting member  155  extending upwardly from the push plate  154 . The fitting member  155  is fitted into the lower end of the piston  122  which is open. An annular snap ring groove  156  is formed on the outer surface of the fitting member  155 . The piston  122  has, at its lower portion, a snap ring  122 - 4  engaging with the snap ring groove  156 . The piston  122  is also provided at its lower end with a radially-extending flange  122 - 1 . A pair of radially-extending protrusions  122 - 2  are formed on the periphery of the flange  122 - 1 . When the piston  122  is received in the syringe receiving chamber  126 , the protrusions  122 - 2  engage with the guide grooves  27  of the housing  120 , respectively, thereby guiding the vertical movement of the piston  122 . A plurality of engaging grooves  122 - 3  are formed on the lower surface of the flange  122 - 1 . When the piston pushing means  150  is fitted into the lower end of the piston  122 , the engaging protrusions  151 - 1  thereof engage with optional ones of the engaging grooves  122 - 3  of the piston  122 . 
       FIG. 23  is a cross-sectional view illustrating the reset button  121  installed on the housing  120 . The reset button  121  is slidably fitted in a hole defined in the upper wall of the housing  120  in such a manner that it is separated from the hole. The reset button  121  is upwardly biased by a compression coil spring so that its upper end is in a state protruded from the hole of the housing  120 . At least one packing seal  121 - 1  is fitted around the reset button  121  to provide a sealing effect between the housing  120  and reset button  121 . 
       FIG. 24  is a block diagram illustrating a control circuit for the above mentioned syringe device. As shown in  FIG. 24 , the control circuit includes the control button unit  123  for generating a control signal adapted to select a desired control function, a control unit  170  provided with functions of a microcomputer and adapted to carry out a control operation in response to the control signal generated from the control button unit  123 , a display unit  124  adapted to display data outputted from the control unit  170 , a ROM  165  adapted to store a variety of data and programs, a motor drive unit  167  adapted to drive a motor  168  under the control of the control unit  170 , and a photocoupler  169  adapted to sense a rotation of the motor  168 . The rotation of the motor  168  is controlled by the motor drive unit  167 . Preferably, the control unit  70  includes a pair of controllers, that is, a first controller  171  and a second controller  172 , which have the same function, in order to maintain a desired function even when one of the controllers  171  and  172  is out of order. The controllers  171  and  172  have terminals P 1  to P 5  and terminals P 1 ′ and P 2 ′, respectively. These terminals are ports connected to data and/or bus lines, respectively. For the motor  168 , a stepping motor or servo motor may be used. 
     Now, the syringe device having the above mentioned configuration will be described. 
     First, the push plate  154  of the piston pushing means  150  is threadedly coupled to the rotating shaft  131  in such a manner that it is disposed at the middle portion of the rotating shaft  131 . Thereafter, the engaging pin  133  is coupled to the lower end of the rotating shaft  131 . Also, the cap type head  131 - 1  is threadedly coupled to the upper end of the rotating shaft  131 . The rotating shaft  131  is then inserted into the lower end of the piston  122  until the fitting member  155  of the piston pushing means  150  is fitted in the lower end of the piston  122 . In this state, the snap ring groove  156   a  of the fitting member  155  engages with the snap ring  122 - 4  of the piston  122 . Also, the engaging protrusions  151 - 1  of the push plate  154  engage with optional ones of the engaging grooves  122 - 3  of the piston  122 . The piston  122 , which is coupled to the rotating shaft  131 , is then fitted in the syringe  21  in such a manner that it is completely inserted into the syringe  21 , as indicated by the double-dotted line in FIG.  22 . In the illustrated case, the engaging grooves  122 - 3  have a small pitch to have the form of gear teeth whereas the protrusions  151 - 1  have a large pitch. In this case, it is possible to achieve an easy assembling process. In order to achieve an easier assembling process, the guide protrusions  122 - 2  of the piston  122  may be eliminated, thereby eliminating the reference position of the piston  122  upon assembling the piston  122 . Of course, the provision of the guide protrusions  122 - 2  provides an advantage in that the piston  122  operates more accurately. In this state, a disposable injection needle (not shown) is fitted onto the tip of the syringe  21 . Thereafter, the injection needle is penetrated into the interior of a phial through the plug of the phial. In this state, the piston  122  is pulled, along with the rotating shaft  131 , to suck a liquid medicine contained in the phial into the syringe  21 , as indicated by the solid line in FIG.  22 . In order to allow the engaging pin  133  of the rotating shaft  131  to be accurately engaged in the cross groove  132 - 1  of the coupling member  132  when the syringe  21  filled with the liquid medicine is inserted into the syringe receiving chamber  126  of the housing  120 , it is necessary to appropriately adjust an initial length of the rotating shaft  131  protruded from the piston  122  in accordance with the amount of the liquid medicine contained in the syringe  21 . In order to achieve an easy and convenient adjustment of the initial protruded length of the rotating shaft  131 , a scale (not shown) may be formed on the housing  120 . Alternatively, a mark (not shown) indicative of a reference position for the rotating shaft  131  may be formed on the housing  120 . Otherwise, a length measuring jig may be used. In this state, the syringe  21 , in which the piston  122  is fitted, is inserted into the syringe receiving chamber  126  of the housing  120  in such a manner that the engaging pin  133  of the rotating shaft  131  is engaged in the cross groove  132 - 1  of the coupling member  132 , as indicated by the arrow in FIG.  20 . When the motor (not shown) drives under the above condition, its drive force is transmitted to the gear  132 - 3  via the power transmission means  130 . Accordingly, the coupling member  132  integral with the gear  132 - 3  rotates. The rotation of the rotating shaft  131  is carried out in a speed-reduced manner because the drive force of the motor is transmitted via the power transmission means  130 . When the rotating shaft  131  rotates, the pushing means  50  moves vertically because the guide protrusion  151  of the push plate  154  is engaged in the guide groove  25  of the housing  120 . 
     The rotation of the coupling member  132  results in a rotation of the rotating shaft  131  because the engaging pin  133  of the rotating shaft  131  is engaged in the cross groove  132 - 1  of the coupling member  132 . For example, when the rotating shaft  131  rotates counter-clockwise, as shown in  FIG. 22 , the push plate  154  moves upwardly while being guided by the guide groove  25 . As a result, the piston  122  coupled to the push plate  154  moves upwardly. Accordingly, the liquid medicine contained in the syringe  21  is injected into the body of the user, into whom the injection needle of the injection needle unit through the connector  2  penetrates, via the connector  2  and feeding tube  1 . As the injection of the liquid medicine is carried out for a prolonged time, the piston  122  reaches its initial position indicated by the double-dotted line in FIG.  22 . In this state, the user separates the injection needle unit from the body and completes the use of the syringe device. Thereafter, the connector  2  of the injection needle unit is separated from the cover  110  which is, in turn, released from the housing  120 . The syringe  21 , piston  122 , pushing means  150  and rotating shaft  131  assembled together are removed from the syringe receiving chamber  126  of the housing  120 . Where it is desired to use again the syringe device, a liquid medicine is filled in the syringe  21  in accordance with the above mentioned piston function. Thereafter, the user rotates the rotating shaft  131  by hand so that the rotating shaft  131  is inserted into the piston  122  to its original position. That is, the rotating shaft  131  is adjusted to have a desired initial length protruded from the piston  122 . In order to achieve an easy adjustment of the initial protruded length of the rotating shaft  131 , it may be possible to use a scale formed on the housing  120 , a mark indicative of a reference position for the rotating shaft  131  formed on the housing  120 , or a length measuring jig. As mentioned above, the reason why the rotating shaft  131  is adjusted to have a desired initial length protruded from the piston  122  is to allow the engaging pin  133  of the rotating shaft  131  to be accurately engaged in the cross groove  132 - 1  of the coupling member  132  when the syringe  21  is fitted in the syringe receiving chamber  126  of the housing  120 . Once the push plate  154  is threadedly coupled to the rotating shaft  131 , it is prevented from being separated from the rotating shaft  131  because the cap type head  131 - 1  is threadedly coupled to the upper end of the rotating shaft  131 . Accordingly, an improvement in durability is obtained. Where the injection of the liquid medicine contained in the syringe  21  is achieved by an upward movement of the piston  122  resulting from an upward movement of the pushing means  150  along the rotating shaft  131 , it is necessary to return the upwardly-moved pushing means  150  to its initial position after refilling the syringe  21  with a liquid medicine to inject again the liquid medicine. However, it is disadvantageous to return the pushing means  150  to its initial position by reversely rotating the rotating shaft  131  using a drive force from the motor. This is because the drive force from the motor is transmitted to the rotating shaft  131  in a speed-reduced manner, so that a lengthy time of about 5 to 10 minutes is consumed for the pushing means to return to its initial position. In this case, accordingly, there is a wastage of time. In order to solve this problem, the rotating shaft  131  is configured to be separable from the motor so that it is manually rotated. Accordingly, it is possible to easily adjust the initial position of the pushing means by a manual rotation of the rotating shaft  131 . The rotating shaft  131  is also configured to be rotated only in one direction by a drive force from the motor. Accordingly, the control of the motor is simplified. This results in a reduction in the manufacturing costs. In particular, all of the cover  110 , battery cover  125 , reset button  121  and bottom cover  140  are sealably configured, even though such a configuration is omitted from the drawings because it is well known. In this case, a vacuum is generated in the interior of the housing  120  as the liquid medicine contained in the syringe  21  is injected into the body of the user. As a result, the piston  122  is overloaded. This problem may be eliminated by forming the reset button  121  using a well-known semi-permeable material preventing penetration of moisture while allowing ventilation of air. In this case, it is possible to prevent a vacuum from being generated in the interior of the housing  120  while still maintaining a moisture sealing effect between the housing  120  and reset button  121 . An increase in the manufacturing costs is incurred when the entire portion of the housing  120  is made of the semi-permeable material. However, where a small part of the housing  120 , for example, the reset button  121 , is made of the semi-permeable material, it is possible to minimize an increase in the manufacturing costs while maintaining an air-permeable effect for the housing  120  and providing convenience in installation. In this case, preferably, at least one packing seal  121 - 1  is fitted around the reset button  121  to provide a desired sealing effect between the housing  120  and reset button  121 . 
     However, such an automatic syringe device performs only the automatic injecting function. Where a diabetic patient uses such a syringe device, there is inconvenience in that the patient has to separately measure his blood sugar level. Also, the doctor should periodically measure the blood sugar level of the patient using a separate blood sugar meter to regulate the quantity of insulin to be dispensed to the patient, based on the measured blood sugar level, resulting in inconvenience to both doctor and patient. Furthermore, the monitoring by the blood sugar meter may be subject to a time error. As a result, it may be difficult to accurately measure the blood sugar level of the patient at a precisely defined time. 
     SUMMARY OF THE INVENTION 
     The present invention has been made in view of the above mentioned problems, and an object of the invention is to provide a portable automatic syringe device capable of displaying the quantity of insulin dispensed to the user and the blood sugar level of the patient measured thereby, while having an automatic insulin injecting function. 
     In accordance with the present invention, this object is accomplished by providing a portable automatic insulin syringe device adapted to enable an injection of liquid medicine for a prolonged time, comprising a syringe pump having a pump housing, comprising: a blood sugar measuring unit mounted at one side of the pump housing and adapted to measure a blood sugar level of a user; a control unit for controlling the blood sugar measuring unit and the syringe pump; and a display unit for simultaneously displaying the quantity of insulin dispensed to a user and the blood sugar level measured by the blood sugar measuring unit. 
     The blood sugar measuring unit may comprise a housing having a lamp hole and an insert hole, a control panel adapted to control a measuring lamp and to convert a measured value from the measuring lamp into a signal capable of being recognized by the control unit, the measuring lamp received in the lamp hole while being outwardly exposed through the lamp hole, a measuring probe fitted in the insert hole, and a fitting protrusion member mounted to the housing in a spring-loaded state and adapted to maintain the measuring probe in a fitted state thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects and aspects of the invention will become apparent from the following description of embodiments with reference to the accompanying drawings in which: 
         FIG. 1  is a block diagram illustrating a control circuit used in a conventional automatic syringe device; 
         FIG. 2  is a cross-sectional view illustrating a structure of the automatic syringe device shown in  FIG. 1 ; 
         FIG. 3  is a perspective view illustrating the installation of a photo sensor in the automatic syringe device shown in  FIG. 1 ; 
         FIG. 4  is a front view illustrating another conventional automatic syringe device; 
         FIG. 5  is a plan view of  FIG. 4 ; 
         FIG. 6  is a cross-sectional view taken along the line A—A of  FIG. 2 ; 
         FIG. 7  is a view illustrating a conventional power transmission means; 
         FIG. 8  is an exploded view illustrating a conventional pushing means; 
         FIG. 9  is a perspective view illustrating an example of a conventional injection needle unit used for portable automatic syringe devices; 
         FIG. 10  is a perspective view illustrating another conventional injection needle unit; 
         FIG. 11  is a partially-broken plan view illustrating the injection needle unit of  FIG. 10 ; 
         FIG. 12  is an enlarged view illustrating a using condition of the injection needle unit of  FIG. 10 ; 
         FIG. 13  is a perspective view illustrating a using condition of the injection needle unit of  FIG. 10 ; 
         FIG. 14  is an enlarged view illustrating a part of the injection needle unit of  FIG. 10 ; 
         FIG. 15  is a view illustrating a drawback occurring when the injection needle unit of  FIG. 10  is used; 
         FIG. 16  is a perspective view illustrating a portable automatic syringe device according to an embodiment of the present invention; 
         FIG. 17  is a plan view of  FIG. 16 ; 
         FIG. 18  is a plan view similar to  FIG. 17 , but eliminating a cover; 
         FIG. 19  is a cross-sectional view taken along the line B—B of  FIG. 18 ; 
       FIG.  20 . is an enlarged perspective view illustrating a part of the automatic syringe device of  FIG. 16 ; 
         FIG. 21  is an enlarged perspective view illustrating a part of the automatic syringe device of  FIG. 16 ; 
         FIG. 22  is a cross-sectional view illustrating the coupled state of the elements of  FIG. 21 ; 
         FIG. 23  is an enlarged cross-sectional view illustrating a reset button installed in accordance with the present invention; 
         FIG. 24  is a block diagram illustrating a control circuit for the syringe device shown in  FIG. 16 ; 
         FIG. 25  is a perspective view illustrating a portable automatic insulin syringe device according to the present invention; 
         FIG. 26  is a sectional view illustrating a blood sugar measuring unit according to the present invention; 
         FIG. 27  is a block diagram illustrating a control circuit for the syringe device according to the present invention; 
         FIG. 28  is a block diagram illustrating a control panel according to the present invention; and 
         FIG. 29  is a graph of a blood sugar level and an insulin level displayed according to the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Now, the present invention will be described in detail, with reference to the annexed drawings. 
       FIG. 25  is a perspective view illustrating a portable automatic syringe device according to the present invention. As shown in  FIG. 25 , the syringe device includes a housing  120 , a syringe  21  separately received in the housing  120 , a piston  122  slidably fitted in the syringe  21  and separately received in the housing  120 , a piston pushing means  150  received in the housing  120  and adapted to vertically move the piston  122 , a power transmission means  130  received in the housing  120  and adapted to generate a drive force, and a rotating shaft  131  received in the housing  120  and adapted to drive the piston pushing means  150  by the drive force transmitted from the power transmission means  130 . The syringe device also includes an injection needle unit (in  FIG. 25 , only its feeding tube  1  and connector  2  are shown). The injection needle unit is connected to the housing  120  by means of a cover  110  which is sealably coupled to the upper end of the housing  120  at one side of the housing  120 . A control button unit  123  is also installed on the housing  120 . The control button unit  123  is electrically connected to a control circuit (not shown) installed in the housing  120  to control the power transmission means  130 . A display  124  such as an LCD is also installed on the housing  120  in order to display the operating state of the syringe device. At the other side of the housing  120 , a battery cover  125  is separately coupled to the upper end of the housing  120  in order to receive a battery in the housing  120 . A reset button  121  is also installed on the housing  120  to generate a reset signal for the control circuit. A bottom cover  140  is also included in the syringe device. These configurations are similar to those of FIG.  16 . 
     In accordance with the present invention, the syringe device further includes a blood sugar measuring unit  200  mounted to one side wall of the housing  120 . The blood sugar measuring unit  200  includes a housing  223  having an insert hole  222 . A measuring probe  230  is inserted into the insert hole  222 , as described hereinafter. 
       FIG. 26  is an exploded sectional view illustrating the blood sugar measuring unit  200  according to the present invention. As shown in  FIG. 26 , the blood sugar measuring unit  200  includes a control panel  210  adapted to control a measuring lamp  211  and to convert a measured value from the measuring lamp  211  into a signal capable of being recognized by a control unit  170  (FIG.  27 ). The housing  223 , which is also included in the blood sugar measuring unit  200 , has a lamp hole  221  for receiving the measuring lamp  211  while outwardly exposing the measuring lamp  211  therethrough. The blooding sugar measuring unit  200  also includes the measuring probe  230  which is fitted in the insert hole  222  provided at the housing  223 . In order to maintain the measuring probe  230  in its fitted state, a fitting protrusion member  224  is mounted to the housing  223  in a spring-loaded state. The measuring probe  230  has a fitting hole  231  for receiving the fitting protrusion member  224 , a light transmitting hole  233  formed at a position corresponding to the measuring lamp  211  in a state in which the measuring probe  230  is fitted in the insert hole  222 , and a measuring plate  235  for covering the light transmitting hole  233 . 
       FIG. 27  illustrates a control circuit for the syringe device according to the present invention. As shown in  FIG. 27 , the control circuit includes a control button unit  123  for generating a control signal adapted to select a desired control function, a control unit  170  provided with functions of a microcomputer and adapted to carry out a control operation in response to the control signal generated from the control button unit  123 , a display unit  124  adapted to display data outputted from the control unit  170 , a ROM  165  adapted to store a variety of data and programs, a motor drive unit  167  adapted to drive a motor  168  under the control of the control unit  170 , and a photocoupler  169  adapted to sense a rotation of the motor  168 . The rotation of the motor  168  is controlled by the motor drive unit  167 . The blood sugar measuring unit  200  is electrically connected to the control unit  170  so that its operation for measuring a blood sugar level is controlled by the control unit  170 . Preferably, the control unit  70  includes a pair of controllers, that is, a first controller  171  and a second controller  172 , which have the same function, in order to maintain a desired function even when one of the controllers  171  and  172  is out of order. The controllers  171  and  172  have terminals P 1  to P 6  and terminals P 1 ′ and P 2 ′, respectively. These terminals are ports connected to data and/or bus lines, respectively. For the motor  168 , a stepping motor or servo motor may be used. 
       FIG. 28  is a block diagram illustrating an embodiment of the control panel  210  according to the present invention. The control panel  210  has a configuration for receiving a command from the control unit and a measured value from the measuring lamp  211 . As shown in  FIG. 28 , the control panel  210  includes a digital/analog (D/A) converter  212  for converting a digital signal, outputted from the control unit  170  at the terminal P 6 , into an analog signal, and a lamp driving unit  213  for driving a light emitting element  211 - 1  of the measuring lamp  211  in response to the signal from the D/A converter  212 . In addition to the light emitting element  211 - 1 , the measuring lamp  211  includes a light receiving element  211 - 2  adapted to receive the light from the light emitting element  211 - 1  reflected by the measuring plate  235 . The control panel  210  also includes a signal receiving/amplifying unit  214  for receiving and amplifying an output signal from the light receiving element  211 - 2  of the measuring lamp  211 , and an analog/digital (A/D) converter  215  for converting an output signal from the signal receiving/amplifying unit  214  into a digital signal, and applying the digital signal to the terminal P 6  of the control unit  170 . 
       FIG. 29  is a graph displayed by the display unit according to the present invention. 
     Now, the operation of the portable automatic insulin syringe device having the above described configuration according to the present invention will be described. Since the insulin injection function of the syringe device is carried out in a general manner, the following description will be made mainly in conjunction with measurement of blood sugar level. The quantity of insulin dispensed to the user by the syringe device of the present invention can be displayed, as shown in FIG.  29 . The measurement of blood sugar level can be easily performed using the blood sugar measuring unit  200  shown in FIG.  25 . The blood sugar measuring operation of the blood sugar measuring unit  200  is controlled by the control unit  170 . That is, when the control unit  170  outputs a measurement enabling signal at its terminal P 6 , as shown in  FIG. 28 , the D/A converter  212  converts the signal from the control unit  170  into an analog signal which is, in turn, amplified by the lamp driving unit  213 . The amplified signal is then applied to the measuring lamp  211 , so that the light emitting element  211 - 1  emits light. The light emitted from the light emitting element  211 - 1  is reflected by the measuring plate  235 , and then received by the light receiving element  211 - 2 . Thereafter, the signal received by the light receiving element  211 - 1  is amplified by the signal receiving/amplifying unit  214 , and then converted into a corresponding digital value by the A/D converter  215 . The digital value is applied to the control unit  170  at the terminal P 6 . The control unit  170  recognizes the value applied thereto, and outputs, to the display unit  124 , the recognized value along with the time at which the value is recognized. The display unit  124  displays the recognized value, as a measured blood sugar level, in the form of a graph, as shown in FIG.  29 . As seen in the graph of  FIG. 29 , the blood sugar level is measured every hour. The control unit  170  outputs a variation of the measured value from a reference value with the lapse of time, in the form of a graph. The type of the graph may be variously designed. 
     Although the preferred embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 
     As apparent from the above description, the present invention provides a portable automatic insulin syringe device capable of measuring and displaying both the quantity of insulin dispensed to the user and the blood sugar level of the user on a display unit. Accordingly, the doctor can conveniently measure the quantity of insulin dispensed to the user and the blood sugar level of the user by simply monitoring the data displayed on the display unit, without separately measuring the insulin quantity and blood sugar level in accordance with a substitution method.