JP4449800B2 - Needleless syringe - Google Patents

Description

  The present invention relates to a needleless syringe that performs a subcutaneous injection by jetting a fixed amount of a chemical solution sucked from an injection hole of a nozzle.

  A needleless syringe is a syringe that injects a chemical solution into a patient's skin by injecting a certain amount of the chemical solution from a nozzle injection hole at the tip of the syringe and then jetting the chemical solution again through the injection hole. In other words, since injection with a needleless syringe does not use an injection needle at the time of subcutaneous injection, there are advantages such as no pain, no injection marks, no injection mistakes, etc. It is also used when injecting.

Such a needleless syringe generally has a structure as shown in FIG. That is, the needleless syringe latches (fixes) or releases the front cylindrical portion 23 in which the nozzle 21 having the injection hole 21a is incorporated and the piston driving rod (hereinafter abbreviated as a piston rod) 25 connecting the piston 24. The rear cylindrical portion 28 incorporating the latch mechanism 22 and the release switch 27 is screwed with a screw portion 29.
A flange ring 25 a is integrally fixed to the front portion of the piston rod 25, and a compression spring 26 is attached between the flange ring 25 a and the rear wall of the rear cylindrical portion 28 through the piston rod 25.

When the rear cylindrical portion 28 of the needleless syringe is rotated forward from the state of FIG. 5, the latch mechanism 22 latches the piston rod 25 and compresses the compression spring 26, and the compression force advances the piston rod 25 forward. Power is energized.
In this state, when the nozzle 21 of the needleless syringe is pressed against the suction port of the drug vial (not shown) and the rear cylindrical portion 28 is rotated backward and moved backward, the drug solution is formed in the space formed between the nozzle 21 and the piston 24. Inhaled. When the release switch 27 is pressed while the injection hole 21a of the nozzle 21 is pressed against the injection site after inhaling a predetermined amount of drug solution, the latch of the latch mechanism 22 is released and the piston rod 25 becomes free and moves forward at high speed. The chemical solution is pressurized by the piston 24 and injected subcutaneously from the injection hole 21a.

In such a needleless syringe, if a strong force is required to push the release switch 27, the syringe cannot be shaken at the time of injection or the nozzle 21 moves from the injection site. I can't make it too strong. For this reason, the piston rod 25 may be erroneously started by accidentally touching the release switch 27 before the injection is performed after inhaling the chemical solution. For this reason, for example, a needleless syringe as shown in a top view (A) and a longitudinal sectional view (B) of FIG. 6 has been devised. This needleless syringe is provided with an L-shaped concave portion 38a at the rear portion of the rear cylindrical portion 38 and a convex portion 37a at the release switch 37, and the ball 31 is rotated when the rear cylindrical portion 38 is retracted. The release switch 37 is rotated via the ball 31. Thereby, the said convex part 37a moves to the advance prohibition zone of the recessed part 38a, the release switch 37 is pushed in automatically, and the false start of the piston rod 35 is prevented.
JP 2001-204819 A

The conventional needleless syringe is configured as described above. However, in order to release the injection lock, that is, to allow the release switch 37 to move forward, the release switch 37 must be rotated each time. Every time it was released, it was necessary to change the syringe, and the operation was troublesome. A method of providing an injection lock member alone is also conceivable, but in this case, after the preparation for injection is completed, the user must remember it.
This invention is made | formed in view of such a situation, Comprising: It aims at providing the needleless syringe which can prevent the erroneous start of a piston rod automatically.

In order to achieve the above object, a needleless syringe according to a first aspect of the present invention comprises means for latching a piston rod and energizing a forward force at the stage of sucking a chemical solution from an injection hole of a nozzle, and a contact portion for locking In a needleless syringe that includes an injection button that releases the latched state of the piston rod after completion of injection preparation for inhaling the medicinal solution, pushes the piston connected to the piston rod into the nozzle at high speed, and ejects the medicinal solution,
An unlock button having an arm for unlocking;
A release button urging means for urging the lock release button in the opposite pushing direction;
A cam having a blocking portion that contacts the locking contact portion and locks the pushing of the injection button, and a lock releasing engagement portion that engages with the unlocking arm;
Cam biasing means for biasing the cam at a position of contact with the locking contact portion;
The cam is opposite to the biasing direction of the cam biasing means by pressing the lock release button, and the lock contact portion and the lock contact portion via the engagement with the lock release arm and the lock release engagement portion. It is arranged to move to a position to release the contact that forms the locked state with the blocking portion.

According to a second aspect of the present invention, there is provided the needleless syringe according to claim 1, wherein the unlocking arm includes the locking contact portion that forms a locked state when the unlocking button is pushed in. A cam holding portion engaged with the unlocking engagement portion so as to hold the cam at a position where the contact with the blocking portion is released;
When the injection button is pushed in the state where the cam is held at a position where the contact that forms the locked state is released, the locking contact portion and the blocking portion engage with each other, so that the cam holding It is arranged to move against the cam biasing means to such an extent that the engagement between the portion and the unlocking engagement portion is released.

According to a third aspect of the present invention, the needleless syringe according to claim 1 is provided with a lock release button capable of releasing the injection lock with one push.
Furthermore, the invention provided by the present invention according to a fourth aspect is the needleless syringe according to claim 3, wherein the injection button and the unlock button are arranged close to each other, and the injection button and the unlock button are interposed therebetween. A partition wall is provided to prevent simultaneous pressing.
According to a fifth aspect of the present invention, in the needleless syringe according to claim 4, the height of the mounting surfaces on both sides of the unlocking button is lower than the height when the unlocking button is pushed. Is.

  The needleless syringe of the present invention is configured as described above, and can prevent injection of a chemical solution due to erroneous start of a piston rod that drives a piston caused by erroneously contacting or pushing an injection button.

  In the needleless syringe according to the present invention, since the lock release button is disposed in the vicinity of the injection button, the unlocking operation of the injection button can be easily performed without the user changing the hand. Further, since the unlock button is operated by a linear motion, the lock can be easily released only by pushing. And if there is an unlock button near the injection button, it is easy to accidentally press both simultaneously, but this mistake operation is eliminated by providing a partition between the injection button and the unlock button, and the right and left of the unlock button The lock release button can be easily pushed by reducing the height when the height of the surface is pushed.

Hereinafter, the needleless syringe of the present invention will be described in detail by way of examples. FIG. 1 is a longitudinal sectional view (A), a rear view (B) and a rear side view (C) showing a configuration of a needleless syringe of the present invention.
The needleless syringe of the present invention is formed by connecting an injection hole 1a and a cylinder 1b as shown in FIG. 1, and inhales a chemical into a space generated when the piston 4 around which the seal member 4a is wound is retracted. A nozzle 1 for injecting a chemical solution from the injection hole 1a is fixed to the tip side by screwing or the like, and a front cylindrical portion 3 having an opening for displaying a chemical amount display window 2 for displaying the amount of the chemical solution sucked into the outer peripheral portion, and the piston 4 The connected piston rod 5, the latch mechanism part 10 for fixing the axial movement of the piston rod 5, the injection button 7 for releasing the latch state of the latch mechanism part 10, and the lock mechanism for locking the movement of the injection button 7 A button in which the injection button 7 and the injection button 7 are arranged in close proximity to each other, the rear cylindrical portion 8 having the portion 13 provided therein, the lock release button 6 that releases the lock state of the injection button 7 in conjunction with the lock mechanism portion 13 And a work unit 15.

  The front cylindrical portion 3 and the rear cylindrical portion 8 are screwed together by a screw portion 9, and the rear cylindrical portion 8 is press-fitted into the button operation portion 15 and integrally coupled. When the front cylindrical portion 3 is fixed and the button operation portion 15 is rotated in the clockwise direction, the rear cylindrical portion 8 moves forward, and when it rotates in the reverse direction, it moves backward.

  The latch mechanism 10 includes a latch groove 12 provided in the piston rod 5, a plurality of small holes 17 provided in the rear cylindrical portion 8, a contact surface 18 provided on the injection button 7, and a compression spring 7b. It is configured. The lock mechanism 13 includes a convex portion (lock contact portion) 7a provided on the injection button 7, a cam 19a formed with a blocking portion 19e and a convex portion (lock releasing engagement portion) 19c, and a cam mounting. The cam 19 includes a cam 19 having a base 19b and an arm 6a having a cam holding portion 6c formed at the tip thereof. The unlocking button 6 is provided with a rearward biasing force by a spring 6b. The cam 19a includes a spring 19d. A counterclockwise rotational force is urged by the spring force. The cam holding portion 6c engages with the convex portion 19c, and includes an engagement portion that moves the cam 19a in the counter-biasing direction of the spring 19d by pushing the lock release button 6, and a holding portion that holds the cam 19a in the unlocked state. Become.

  In the above needleless syringe, the injection button 7 and the unlocking button 6 are push-type ones, and by disposing them close to each other, the user does not have to hold the syringe to change the position of the injection button 7. The locked state can be released by pressing the unlock button 6 and then the injection button 7 can be pressed to perform injection.

  Further, by providing a partition wall 20 between the injection button 7 and the unlock button 6, when the lock release button 6 is pressed, the injection button 7 is accidentally pressed at the same time, so that the medicinal solution is injected at a place other than the injection site. You can eliminate mistakes.

  Furthermore, the height of the left and right surfaces to which the unlocking button 6 is attached is set to be lower than the height of the pushing surface when the unlocking button 6 indicated by the dotted line in FIG. Even if the position where the lock release button 6 is pressed is shifted to the left or right from the center, it can be easily pushed in, and the operation with one hand is facilitated.

  In order to inhale and inject a drug solution with the needleless syringe, first, as shown in FIG. 1, the button operating portion 15 is rotated clockwise to advance the piston 4 to the inner tip of the nozzle 1. At this time, the scale value of the drug solution amount display window 2 indicates 0, and the ball 11 is fitted in the latch groove 12 and pressed by the contact surface 18 of the injection button 7, that is, the piston rod 5 is latched in the rear cylindrical portion 8. It will be in the state. Further, the convex portion 7 a provided on the injection button 7 moves to the right side of the cam 19 a of the cam portion 19 provided on the rear cylindrical portion 8. Since a counterclockwise force is applied to the cam 19a by a spring 19d, in this state, the forward movement of the convex portion 7a is blocked by the blocking portion 19e of the cam 19a, so that the injection button 7 can be pushed in. Can not. With reference to the longitudinal sectional views of the needleless syringe of FIGS. 2 to 4 in detail, the operation of the needleless syringe from this state until the medical solution is inhaled and ejected, in particular, the operation of the lock mechanism 13 which is a feature of the present invention. This will be described below.

  In order to inhale the drug solution into the needleless syringe of FIG. 1, the front cylindrical portion 3 of the needleless syringe is grasped and the injection hole 1a of the nozzle 1 is pressed against the suction port of the drug vial (not shown), The button operating portion 15 is rotated counterclockwise while the front cylindrical portion 3 is fixed until the amount of the chemical solution is inhaled. As a result, the rear cylindrical portion 8 moves backward in conjunction with the button operating portion 15 while the piston rod 5 is latched, and a predetermined amount of chemical solution is sucked into the space between the piston 4 and the cylinder 1b. During this time, the lock mechanism 13 maintains the state shown in FIG.

  Next, in order to perform injection, the unlocking button 6 located at the dotted line in FIG. 2 is pushed while the needleless syringe that has inhaled the medicinal solution is applied to the injection hole with the injection hole 1a. Then, the lock release button 6 moves to the solid line position, and the tip of the arm 6a of the cam holding portion 6c also moves forward. As the arm 6a moves, the cam 19a of the cam portion 19 gradually turns clockwise, and the triangular protrusion 19c provided on the cam 19a and the cam holding portion 6c of the arm 6a are engaged as shown in FIG. Then, the convex portion 7a of the injection button 7 moves to the right side of the cam 19a, and the lock mechanism portion 13 of the injection button 7 is released, that is, the injection standby state.

  When the injection button 7 is pushed in the injection standby state, the lock mechanism 13 is in the state shown in FIG. That is, as shown in FIG. 3, the convex portion 7a of the injection button 7 moves to the left over the blocking portion 19e of the cam 19a while rotating the cam 19a of the cam portion 19 in the clockwise direction, and at the same time, the cam holding portion 6c of the arm 6a. And the projection 19c are released, and the lock release button 6 returns to the rear position by the biasing force of the spring 6b. Then, the contact surface 18 of the injection button 7 moves to the front of the small hole 17 and the ball 11 becomes free and comes out of the latch groove 12 by the urging force of the piston rod 5 forward, and the piston rod 5 and the rear cylindrical portion 8 are latched. Is released, and the piston rod 5 moves forward at high speed. The chemical solution in the space is pushed by the piston 4 to become a high pressure, and is injected from the injection hole 1a for injection.

  In order to inhale the drug solution into the needleless syringe again, the button operation unit 15 is rotated, and the rear cylindrical unit 8 is pushed to a position where the display of the drug solution amount display window 2 becomes zero. When the small hole 17 of the rear cylindrical portion 8 reaches the latch groove 12, the ball 11 falls into the latch groove 12 as shown in FIG. Then, the injection button 7 is retracted in the direction indicated by the dotted line by the rearward biasing force of the compression spring 7b, presses the ball 11 with the contact surface 18 and is latched, and the convex portion 7a causes the cam 19a to rotate clockwise. To move to the right side of the cam 19a and return to the state of FIG.

  As shown in the above embodiment, the needleless syringe is provided with a lock release button 6 for releasing the lock of the injection button 7 in close proximity to the operation surface to which the injection button 7 for releasing the latch of the piston rod 5 is attached. Thus, the injection can be easily performed without re-gripping, and the configuration of the present invention is not limited to the embodiment. For example, the lock release button 6 can be disposed on the upper side of the injection button 7 or the heights of the lock release button 6 and the injection button 7 can be changed.

  It is used for a needleless syringe that performs a subcutaneous injection by jetting a fixed amount of a chemical solution sucked from an injection hole of a nozzle.

It is a longitudinal cross-sectional view (A), a rear view (B), and a rear side view (C) showing a configuration of a needleless syringe according to an embodiment of the present invention. It is a longitudinal cross-sectional view which shows the state of the lock mechanism part at the time of lock release of an injection button. It is a longitudinal cross-sectional view which shows the state of the lock mechanism part at the time of latch release by an injection button. It is a longitudinal cross-sectional view which shows the state of the latch mechanism part during chemical | medical solution inhalation. It is sectional drawing of the conventional needleless syringe. It is the top view (A) and longitudinal cross-sectional view (B) of the conventional needleless syringe.

Explanation of symbols

1, 21 Nozzle 1a, 21a Injection hole 1b Cylinder 2 Chemical liquid amount display window 3, 23 Front cylindrical part 4, 24 Piston 4a Seal member 5, 25, 35 Piston rod 6 Lock release button 6a Arm 6b, 19d Spring 6c Cam holding part 7 Injection button 7a, 19c, 37a Convex part 7b, 26 Compression spring 8, 38, 28 Rear cylindrical part 9, 29 Screw part 10 Latch mechanism part 11, 31 Ball 12 Latch groove 13 Lock mechanism part 15 Button operation part 17 Small Hole 18 Contact surface 19 Cam part 19a Cam 19b Cam mount 19e Blocking part 20 Bulkhead 22 Latch mechanism 25a Flange ring 27, 37 Release switch 38a Concave part

Claims (5)

There is a means to latch the piston rod and bias the forward force at the stage of inhaling the chemical liquid from the nozzle injection hole, and a locking contact part, and release the latched state of the piston rod after preparation for injection to inhale the chemical liquid is completed In a needleless syringe that includes a syringe button that pushes a piston connected to the piston rod into the nozzle at a high speed and ejects a drug solution,
An unlock button having an arm for unlocking;
A release button urging means for urging the lock release button in the opposite pushing direction;
A cam having a blocking portion that contacts the locking contact portion and locks the pushing of the injection button, and a lock releasing engagement portion that engages with the unlocking arm;
Cam biasing means for biasing the cam at a position of contact with the locking contact portion;
The cam is pressed against the lock abutment portion and the lock release engagement portion with the lock release engagement portion and the lock release engagement portion against the urging direction of the cam urging means by pressing the lock release button. A needleless syringe, wherein the needleless syringe is disposed so as to move to a position where a contact that forms a locked state with the blocking portion is released. The unlocking arm is configured to release the lock so that the cam is held at a position where the contact between the locking contact portion and the blocking portion forming the locked state is released when the unlock button is pushed in. A cam holding part that engages with the contracting part,
When the injection button is pushed in a state where the cam is held at a position where the contact that forms the locked state is released, the locking contact portion and the blocking portion engage with each other, so that the cam holding 2. The needleless syringe according to claim 1, wherein the needleless syringe is disposed so as to move against the cam urging means to an extent that the engagement between the portion and the engagement portion for unlocking is released. The needleless syringe according to claim 1, further comprising a lock release button capable of releasing the injection lock with a single push. 3. The needleless syringe according to claim 2, wherein the injection button and the lock release button are arranged close to each other, and a partition wall is provided between the injection button and the lock release button to prevent simultaneous pressing of the injection button and the lock release button. . The needleless syringe according to claim 3, wherein the height of the mounting surfaces on both sides of the unlock button is lower than the height when the unlock button is pushed.

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