JPH0611337B2 - Syringe and dosage adjustment device - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a device suitable for dispensing a metered quantity of liquid from a container,
The present invention relates to a syringe that is specifically configured to measure and inject substances such as insulin and growth hormone.

[0002]

BACKGROUND OF THE INVENTION Diabetic and other patients often are unable to meet specialists who will administer liquid injections for subcutaneous and intramuscular injections, and then administer those injections. Under such circumstances, these people are looking for an inexpensive syringe that does not require a specialist to accurately measure the desired amount. Also, these people often need more than one dose per day, each with somewhat different doses. This kind of syringe has
It is known to have a shape similar to a pen or a mechanical pencil, but it is inevitably large in size because it has a dosage for many doses. How convenient is it if it is small enough to be carried in your pocket? Examples of these devices are described in US Pat.
60, 4498904, and 4592745. Further examples are PCT Publication WO 87/02895 and WO 88.
/ 07874. In this type of device, the container containing the liquid has a closed first end modified to allow the liquid inside the container to flow out of the closed first end for the purpose of subcutaneous or intramuscular injection. The second end of the container is generally bound by a piston. To prevent reuse of the liquid container, the piston is designed to exert a pressing force to reduce the liquid volume of the container, but there is no feature to pull out the piston to expand the liquid volume of the container. Absent. An elongated plunger is housed inside the housing for exerting a force on the piston closing the second end of the container. When the liquid in the container flows out, the volume of the container also decreases. One method of determining the amount of decrease is to measure the distance traveled by the plunger. The syringe should be equipped with features that allow the plunger to move only in one direction towards the piston, in order to prevent any movement on the plunger side so as not to increase the volume of the liquid container. Is considered to be. The cap is mounted over a needle assembly, which is typically mounted on the closed side of the container.

[0003]

Although the known art syringe has been successful in the past, it does have some drawbacks. With some known pen injectors, once the dosage to be infused has been adjusted, it cannot be accurately reduced to a small dose. This results in the consumption of the medication liquid inside the syringe. Dosage indications are difficult to read with some known pen injectors. In the prior art pen injector, the patient had to read two scales to know the dosage, or to do so, the dosage had to be recalculated. In addition, many prior art devices are commonly used repeatedly by replacing the container inside the syringe, but the use of such syringes is associated with unprescribed substances, Immoral.

[0004]

In order to solve these drawbacks in the above-mentioned known art, the syringe according to the present invention contains a liquid container similar to that known in the known art. A housing for receiving a plunger, but a plunger is housed inside the housing for exerting a force on a piston closing the second end of the container. The plunger has a non-cylindrical cross section with a threaded first surface and a second surface that optionally includes a series of trailing teeth. A collar is housed inside the housing adjacent the second end of the container to hold the liquid container inside the housing. The collar has a non-cylindrical clearance that normally matches the cross section of the plunger. The plunger passes through a non-cylindrical gap, but its collar prevents it from rotating with respect to the housing. One means on the collar side engages the second surface of the plunger, thereby limiting movement of the plunger from the container. A hollow cap encloses the end of the plunger located opposite the liquid container. The hollow cap skirt extends inside the housing. The cap has an internal threaded surface that movably engages the plunger for associated scale adjustment. This scale adjustment can increase or decrease the dosage to be injected from the pen injector. A stopper is formed inside the housing, and the hollow cap has a front end-facing surface. This prevents the hollow cap and the plunger as a unit from moving linearly towards the container. Overall, the device is made from inexpensive materials and is configured for machine production in order to achieve low cost as a readily available device. As described above, the dosage adjustment can increase or decrease the dosage, but this can reduce wasteful consumption of the liquid to be administered. This dosage indication is simple and straightforward to read, and is thus a characteristic that allows a more accurate and effective use of the dosing liquid injected from the device.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The syringe according to the embodiment of the present invention shown in FIGS. 1 to 5 (E) will be described in detail below.

A syringe 10 according to an embodiment of the present invention is shown in FIGS. This syringe has a tip 18 and a first
Inside the tip region 15 located between the shoulders is provided a housing 12 adapted to house a liquid container 14 for containing a liquid. The base region 13 between the first shoulder 17 and the base end 16 is adapted to accommodate the dictated adjusting device. The base region 13 is
It is provided with a ribbed region 19 which provides the grading function and the correct dose injection function from the syringe. Tip 1 of housing 12
8 is configured to house the needle assembly 20. The needle assembly 20 has a double-ended needle 22. The tip 24 of the double-ended needle 22 is configured to allow subcutaneous or intramuscular injection. The needle assembly 20 also includes a proximal end 23 configured to penetrate the rubber end cover 26 of the container 14. Although the liquid container 14 is fixed inside the housing 12 by a collar 28. The collar 28 has an outer diameter that contacts the inner wall of the base region 13 of the housing 12. Color 28
The entire surface 30 of the container 14 adjacent to the first shoulder 17
It is adapted to come into contact with the proximal end 32 of the. The container 14 is formed from a cylindrical body 34 containing a piston 36 located near the proximal end 32 of the container 14. The piston 36 is movable with respect to the cylindrical body 34 so as to determine a capacity capable of accommodating the container 14.

Needle assembly 20 such that container 14 is placed inside housing 12 and, after being held in place by collar 28, engages with threads 40 formed on the distal surface of housing 12.
The needle assembly 20 and the tip 18 are joined together by suitable fastening means such as threads 38 formed on the inner surface of the. Needle assembly 20 is housing 1
Double-ended needle 2 when fully joined with 2
The proximal end 23 of 2 penetrates the rubber end cover 26 present on the end cap 42 of the liquid container 14 so that the liquid present inside the liquid container 14 can pass through the inside of the double ended needle 22.

The safety shield 44, which includes the sheath portion 46 and the connecting portion 48, is snapped into contact with the needle assembly 20, thereby protecting the injection needle. Cap 5 with clip 54
2 covers the tip portion of the housing 12, the needle assembly 20, and the safety shield 44. Clip 54
Together, the sidewalls of housing 12 provide a convenient means of securing the syringe in the pocket.

The syringe also includes a liquid container 14
A plunger 56 having a tip 58 which contacts the piston 36 of the. Plunger 56 has a non-cylindrical cross-section with a larger radius first surface 60 that includes threads 62 and a smaller radius second surface 64. The plunger 56 is inserted inside the opening 68 of the collar 28. Interference between the opening 68 in the collar 28 and the non-cylindrical cross-section of the plunger 56 prevents rotation of the plunger 56 within the housing 12.

As shown in FIG. 1, the inner surface portion 70 of the collar 28 has a protrusion 71. The protrusion 71 digs into the second surface 64 of the plunger 56 to allow the housing 12
Restricting movement of the plunger 56 toward the base end 16 of the. Protrusion 71 on inner surface 70 of collar 28
Allows the plunger 56 to move towards the tip of the syringe 10, which reduces the container volume. Alternatively, as shown in FIG. 2, the second surface 64 may have a series of ratchets 66. In order to regulate the backward movement of the plunger 56, the ratchet 66 is provided on the inner surface 7 of the collar 28 even if no bear hand is present.
Can interact with zero. However, in the case of follow-up teeth, the movement of the plunger is different between the teeth, so it is rather preferable to hold the bear hand. The one with the bear's hand has a less interdental movement, which allows for finer dosage adjustment.

A two-part hollow cap 72 substantially houses a plunger 56 having a proximal end 50. The cap 72 includes a tip portion 74 and a base portion 86.
However, these can be produced separately for structural simplification. The tip portion 74 comprises a cylinder 76 having a threaded inner surface 78 on the tip 80 side. The base portion 86 has a slightly larger outer diameter than the tip portion 74, and the base end 82 of the tip portion 74 is fixed to the base portion 86 of the cap 72. The proximal end 88 of the proximal portion 86 always projects from the housing 12 and has serrations 90 formed on its surface to facilitate adjustment of the amount of liquid to be injected using the syringe 10. The cap 72 has a graduation 92 for visually indicating the amount of liquid to be measured, and also has a radially projecting protrusion 94 that interacts with the rib-like region 19 of the housing 12. This protrusion 94
Serves to audibly indicate the degree of rotation of the cap 72 relative to the housing 12. The action of the protrusion 94 causes the cap 72 to move linearly with respect to the housing 12 when a force is exerted normal to the proximal end 98 of the cap 72.

In operation, when injecting a metered liquid, the housing 12 is first grasped with one hand and then the serration 90 of the cap 72 is grasped with the other hand. Here, if the cap 72 is turned counterclockwise, the threaded inner surface 78 of the cap 72 moves along the thread 62 of the plunger 56. This rotation does not move the plunger 56 relative to the housing 12, but the tip 84 of the proximal portion 86 retracts from the restraining shoulder 49 inside the housing 12.
Further, the counterclockwise rotation of the cap 72 causes the scale 92 to move above the base end 16 of the housing 12 to indicate the increase.

When using this insulin syringe, it is desirable that the scale 92 be calibrated according to international units. When used for injection of other drugs, the calibrating work can be performed in units suitable for those drugs so as to avoid the troublesome dose calculation. The dose scale displayed by the scale 92 can be read directly at the end of the proximal end 16 of the housing 12. The dosage corresponds to the quantity displayed on the step line 93. In order to calibrate the scale 92 in international units or units commensurate with the drug used, the solution contained in the liquid container 14 should be capable of eliciting the desired physiological response on the scale of the scale 92. Further, it is preferable to concentrate or dilute. If the cap 72 is rotated excessively, it can be rotated clockwise to reduce the dose of the dose without changing the position of the plunger 56 relative to the housing 12.

After the cap 72 has been positioned to the desired dosage as measured by the scale 92, the safety shield 44 and the cap 52 can be removed to allow the syringe to be used. When pressure is applied to the proximal end 98 of the cap 72, the cap 72 moves linearly toward the tip 18 of the housing 12 until the radially projecting portion of the tip 84 contacts the stop shoulder 49. Cap 72
When is moved, the plunger 56 moves in the same direction, so that the plunger 56 moves inside the collar 28 and then moves the piston 36 inside the liquid container 14 to push out the liquid inside. After use, the double-sided cutting needle 22 is pulled out, and the safety shield 44 and the cap 52 are returned to their original positions.

FIG. 3 shows a modified tip portion 10 of the cap 72.
0, an additional part 104 that engages the threaded outer surface 106 of the modified tip portion 100, and a bounding ring 108 secured in the upper portion of the housing 12. The tip 110 of the modified tip portion 100 is substantially
It has the same diameter as the tip 74 and has a threaded inner surface 112 similar to the threaded inner surface 78 of the tip portion 74.

When assembled from the arrangement of FIG. 4, the add-on component 104 is snapped onto the threaded outer surface 106 of the modified tip portion 100. Border ring 10
8 slides over modified tip 100. The plunger 56 is then fully inserted within the modified tip portion 100 so that the plunger 56 and collar 28 can be smoothly interlocked when the device is assembled. The tip 84 of the proximal portion 86 is then connected to the proximal end 114 of the modified tip portion 100. The two proximal portions 86 and modified tip portion 100 can be joined by conventional means such as ultrasonic welding or solvent. The demarcation ring 108 is then pushed with its assembly into the interior of the housing 12 until it is in the apparent position 116. The boundary ring 108 is again joined to the housing 12 using solvent or ultrasonic welding or conventional techniques. The housing 12 has lateral holes 118 not included in FIG. To adjust the add-on part 104,
It may be brought close to the lateral hole 118 while being engaged with the outer surface 106.

The operation of the embodiment shown in FIGS. 3 and 4 is as follows.
This is best shown in FIGS. 5 (A)-(E). FIG. 5 (A) shows the syringe 10 corresponding to the present embodiment in the initially assembled state. Here, the tip 58 of the piston 56 is shown slightly projecting beyond the collar 28. As shown in FIG. 2, the tip 5
When 8 is located at the back of piston 36, liquid container 14 is shown to clearly show the movement of the plunger.
And the piston 36 is omitted. The position of the plunger shown in FIG. 5 (A) is practically the same as the position of the plunger shown in FIG. 2, that is, the plunger 56 practically extends over the entire length of the cap 72. I understand.

As can be seen by comparing FIG. 5 (A) and FIG. 4, the additional component 104 has the tip 110 of the improved tip portion 100.
Until it touches the threaded outer surface 106. Boundary ring 108 includes housing 12
Being fixed inside, the end 120 of the bounding ring 108 effectively abuts the base end of the lateral hole 118. The tip 84 of the base side portion 86 of the cap 72 is in contact with this stopper.

To inject a metered quantity of liquid to be metered, grasp the base end 88 of the cap 72 and cap from the position shown in FIG. 5 (A) to the position shown in FIG. 5 (B). Rotate in the direction (R) shown in. Due to this rotation, the tip 84 is sent backward by the distance D. This rotational movement of the cap causes the projection 94 to cross over the straight groove 96,
At this time, the protrusion 96 has a function of audibly indicating the rotation amount related to the unit amount of the special drug to be injected. This backward movement exposes most of the scale 92, and the desired dosage is indicated by the number on the scale 92. For the embodiment shown in Figures 1 and 2, as already mentioned, if the cap 72 is over-rotated, it may be rotated in the opposite direction to reduce the required dosage. Good. A feature that is not present in the embodiment shown in FIGS. 1 and 2 and that is present in the embodiment shown in FIGS. 3-5E is that it is at every location along the threaded outer surface 106. The presence of the matching additional component 104. The basic function of the additional component 104 is to set the maximum measurable quantity, which makes the syringe more difficult to remember the proper dosage and the significance of the scale 92. It will be used by people with physical imperfections that are not fully understood. In such a situation, as shown in FIG. 5B, the cap 72 can be initially rotated in the direction of the desired maximum weight value. Next, additional parts 1
04 is rotated from the position shown in FIG. 5 (B) to the position shown in FIG. 5 (C) so that the distance becomes X. In this position, the upper end 124 of the add-on part 104 abuts the end 120 of the boundary ring 108. The interlocking of the add-on part 104 with the threaded outer surface 106 should be such that the add-on part 104 is slightly difficult to move, or
At least, it is necessary to prevent the additional component 104 from moving due to a slight vibration or the like.

With the add-on component 104 in the position shown in FIG. 5C, the cap 72 can be screwed back to its original position. This unscrewed rotational movement relative to its original position or zero does not cause any movement of the plunger 56 relative to the collar 28 so that the liquid in the syringe does not drain. Furthermore, a force can be exerted in the direction of the proximal end 98, as indicated by arrow F. This allows the cap 72 and the plunger 56 to
Is the tip 84 from the position shown in FIG.
Move the distance traveled until it touches the base end 122 of the boundary ring 108. It can be seen that if a force F is applied to the proximal end 98, both the cap 72 and the plunger 56 will move linearly a distance L which is the same as the distance D shown in FIG. 5B. The movement of the plunger 56 is
As already explained, in order to drain the liquid inside the liquid container 14, the forward movement of the piston 36 is caused as shown in FIG.

The syringe 10 may be stored in the position shown in FIG. 5D until it is used the next time. The inner surface 70 of the collar 28 is intended to prevent any relative movement between the housing 12 and the plunger due to simple vibration or shock.
When the syringe needs to be used again, rotate the cap 72 in the direction of arrow R again from the position shown in FIG. 5 (D) to the position shown in FIG. 5 (E). Just go. The rotational movement of the cap 72 with respect to the housing 12 does not cause any relative movement between the housing 12 and the plunger 56. 5 (C) to 5 (E)
While the add-on component 104 in the position shown in FIG. 1 limits the maximum dose, if the add-on component 104 does not return the cap 72 to the position where it abuts the boundary ring 108, a single dose Will be less.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a syringe according to an embodiment of the present invention.

FIG. 2 is a detailed cross-sectional view in which medication can be adjusted by the syringe of FIG.

FIG. 3 is an exploded perspective view of another embodiment of the present invention with a hollow cap having a maximum dose limiting feature.

FIG. 4 is a cross section of the embodiment of FIG. 3 assembled in one piece.

5 (A)-(E) are cross-sectional views sequentially showing five different positions for limiting dosage in the embodiment of FIG.

[Explanation of symbols]

 10 Syringe 12 Housing 13 Base region 14 Liquid container 15 Tip region 16 Base end 17 First shoulder 18 Tip 19 Rib-like region 20 Needle assembly 22 Double-ended needle 23 Base end 24 Tip 26 Rubber end cover 28 Color 30 Full surface Part 32 Base end 34 Cylindrical body 36 Piston 38 Thread 40 Thread 42 End cap 44 Safety shield 46 Sheath part 48 Connecting part 49 Stop shoulder 50 Base end 52 Cap 54 Clip 56 Plunger 58 Tip 60 First surface 62 Screw Mountain 64 Second surface 66 Ratchet 68 Opening 70 Inner surface 71 Protrusion 72 Cap 74 Tip part 76 Cylindrical 78 Threaded inner surface 80 Tip 82 Base end 84 Tip 86 Base part 88 Base end 90 Serration 92 Scales 93 Step Lines 94 Protrusions 96 Straight Grooves (Base Side Part) 98 Base End 100 Improved Tip Part 104 Additional Parts 106 Threaded Outer Surface 108 Boundary Ring 110 Tip 112 Threaded Inner Surface 114 Base Side end 118 Side hole 120 End 122 Base end 124 Upper end

Claims (3)

[Claims] 1. A device for adjusting the dosage of a liquid to be injected from a syringe having a housing for housing a liquid container and a plunger housed in the housing, wherein the liquid container is closed. At the end,
A housing having a second end closed by a piston, the housing having a proximal end and a tip, the tip housing an injection needle assembly for allowing a medicinal solution to flow out of the first closed end of the container. Is configured to
A plunger is provided in the housing to prevent rotation of the plunger relative to the housing in syringes and dose adjustment devices configured to exert a force on a piston closing the second end of the container. A first means, a second means comprising a protrusion engaging the first surface of the plunger to limit movement of the plunger toward the proximal end of the housing, and a proximal end of the housing relative to the plunger and the housing. Means for engaging the second surface of the plunger for graduation to the third and third means in a fixed position relative to the housing.
Syringe and dosage adjustment device, characterized in that the means comprises a fourth means mounted with respect to the housing to prevent any movement of the housing in the distal direction. 2. A syringe having a dose adjusting device for a liquid to be infused, the first container containing a liquid container and the base end and the liquid being closed in the container.
A housing having a tip configured to house a needle assembly to allow it to flow out of the end, and a housing contained within the housing to exert a force on a piston closing the second end of the liquid container. A plunger having a non-cylindrical cross-section having a threaded first surface and a second surface, and housed in a housing adjacent a second end of the liquid container; A second of the plunger for limiting the movement of the plunger towards the proximal end of the housing, having a non-cylindrical opening that conforms to the cross section of the plunger to prevent rotation of the plunger with respect to the housing
A collar having protruding means for engaging the surface and a distal end of the plunger opposite the liquid container and extending outwardly from the proximal end of the housing,
Has a screw inner surface that is movably screwed with the first surface portion of the plunger for adjusting the scale, and when moving the cap and the plunger in the distal direction of the housing,
A hollow cap having a tip-facing surface in contact with a stopper fixed with respect to the housing. 3. A syringe having a housing for containing a liquid container, the housing for containing an injection needle assembly for allowing liquid to flow from a proximal end and a closed first end of the container. Having a tip configured to and a dose adjusting device for a liquid to be injected, the syringe housed in a housing for exerting a force on a piston closing a second end of the liquid container. A plunger having a non-cylindrical cross-section having a threaded first surface and a second surface; and a housing contained within the housing adjacent the second end of the liquid container; Having a non-cylindrical opening that conforms to the cross section of the plunger to prevent rotation of the plunger with respect to A collar having protrusion means for engaging the second surface of the plunger to limit the movement of the plunger and a distal end of the plunger opposite the liquid container, and outward from the proximal end of the housing. Has a threaded inner surface that extends toward the front surface of the plunger and is movably screwed with the first surface portion of the plunger for adjusting the scale, and when the cap and the plunger are moved in the distal direction of the housing, the housing A hollow cap having a stopper facing and a tip-facing surface in contact with the thread, a threaded portion formed on the outer surface of the hollow cap, and an adjustable scale limit of the cap relative to the plunger. An add-on member that mates with the threaded outer surface portion of the cap.