JPS5997671A - Syringe injection apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. BACKGROUND OF THE INVENTION Technical Field The present invention relates to a syringe injection device having an overload detection mechanism that allows a liquid medicine in a syringe to be injected into a patient.

Prior Art Conventionally, when treating patients, in order to continuously administer anti-cancer drugs, various antibiotics, etc. to the patient in small amounts over a long period of time,
A syringe injection device is used.

As shown in FIGS. 1 and 2, the conventional syringe injection device 1 converts the rotational force of a drive motor 3 fixed to a cabinet 2 into a driven gear via a drive gear 4, a driven gear 5, and a drive screw 6. The syringe holding portion 8 formed on the outer surface of the cabinet 2 transmits the force to the pushing head 7 with which the nut is integrated, and moves the pushing head 7 in the direction of the pushing force.
The pusher 9A of the syringe 9 held in the syringe 9 is pushed at a predetermined speed so that the liquid in the syringe 9 can be continuously injected into the patient over a long period of time.

Here, in the syringe injection device 1, the liquid transport pipe connected to the tip 9B of the syringe 9 may be bent and become non-conducting, or the patient side tip of the liquid transport pipe may be bent.
This may cause a blockage in the connected injection needle or the syringe 9.
If an abnormal condition occurs such as the pusher 9A becoming impossible to move due to abnormal deformation of It becomes impossible to move the head 7 at a predetermined speed, and not only is it not possible to secure a predetermined injection speed, but there is a risk that the injection will stop, putting the person in a serious condition.

Therefore, in the conventional syringe injection device 1, a rotation detector 3A such as a tacho generator or a rotary encoder is directly connected to the MA drive motor, and changes in the rotation speed of the drive motor 3 are detected to obtain an overload detection signal. , detects occurrence of upper F abnormal condition, and detects f? : It is possible to generate information, etc.

However, in the case of the above-mentioned syringe devices 11, a negative torque higher than the rated torque is applied to the drive motor,
Since an overload detection signal is obtained by detecting the rotational speed change, the life of the drive motor is shortened. Furthermore, a detector is required to detect changes in the rotational speed of the P3AKiJJ motor, making the overall overload detection mechanism complicated.

■ Purpose of the Invention The present invention provides a syringe injection device having an overload detection mechanism that has a simple structure and can quickly detect abnormalities in injection operation while minimizing the load torque acting on the drive motor. The purpose is to provide equipment.

■Structure of the Invention In order to achieve the above object, the present invention is designed to push a syringe held in a syringe holding part on a cabinet by a pushing head that is movable by the rotational force of a drive motor fixed to the cabinet. In a syringe injection device that is capable of pushing a pusher, a drive gear supported at a predetermined position relative to the cabinet and capable of interlocking with the drive motor;
a driven gear supported at a predetermined position with respect to the cabinet and capable of interlocking with the pushing head; a movable plate supported so as to be movable along a predetermined path with respect to the cabinet; an intermediate gear capable of meshing with the drive gear and the driven gear when the plate remains at the first gear position lζ; A mechanism comprising a holding means for retaining the plate at the meshing position, and a detection means for detecting movement of the movable plate from the meshing position when the load acting on the pushing head exceeds a predetermined value. It is equipped with a load detection mechanism.

Further, in the syringe injection device according to the present invention, the holding means is a spring.

Further, in the syringe injection device according to the present invention, the movable plate is a rocking plate whose rocking center is the rotation center of the driven gear.

■ Detailed description of the invention Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 shows a syringe injection device 10 according to one embodiment of the present invention.
4 is a sectional view taken along the line ■-■ in FIG. 3, FIG. 5 is a sectional view taken along line V-V and 1g in FIG. 3, and FIG. 6 is a sectional view taken along line 1f and li side views taken along the Vi line lζ, FIG. 7 is a view taken along the line ■--b in FIG. 3, and FIG. 8 is a perspective view showing the same syringe injection device 1o.

A syringe holding part 13 for holding the syringe 12 in a predetermined position is formed on the outer surface of the cabinet 11 of the syringe injection device ff110. The syringe holding portion 13 includes an engagement groove portion 1 into which the flange portion 14 of the syringe 12 can be inserted.
At the same time, the clamp arm 17 that can press and hold the outer cylinder part 16 of the syringe 12 is collapsed. The clamp arm 17 is capable of pressing the outer cylindrical portion 16 of the syringe 12 under the urging force of a compression spring 18 housed in the cabinet 11. A drive motor 19 whose rotational speed can be controlled is fixedly arranged, and a drive screw 20 is rotatable. Here, the drive screw 20 is arranged parallel to the central axis of the syringe 12 held by the syringe holding part 13.

Note that the drive motor 19 and the drive screw 20 are connected via a gear train, which will be described later.

Moreover, a slide groove 23 is carved on the outer surface of the cabinet 11. The slide groove 23 is connected to the syringe holding part 1
The slides R2 and 3 extend in the same direction as the longitudinal direction of the syringe 12 held in the non-jigging holding part 13, and the slides R2 and 3 include a) a pusher that allows pushing the pusher 24 of the syringe 12 held in the non-jigging holding part 13; The base of the head 25 is slidably positioned. In addition, in the figure, 26 is a head cover of the pushing head 25.

One end of a connecting pipe 27 is fixed to the queen pushing head 25. The connecting pipe 27 extends parallel to the drive screw 20, and its intermediate portion is inserted into an insertion hole 29 formed in the vertical wall portion 28 of the cabinet 11 so as to be movable in the axial direction in a liquid-tight manner. , the other end is located within the cabinet 11. Note that the connecting pipe 27 is inserted into the insertion hole 29.
A sealing member 30 is joined to ensure a liquid-tight state. At the other end of the connecting pipe 27, a holding member 3 is provided.
1 is fixed. The holding member 31 has a protrusion 32
is carved parallel to the drive screw 20 and is slidably engaged in a guide (future 33) in the cabinet 11.The holding member 31 also has side walls 34A, 3
The intermediate portion of the drive screw 20 can be inserted into the hole 35 formed in the hole 4B. Note that the other end of the connecting pipe 27 passes through one side wall portion 34A of the holding member 31.

The hollow main 6B of the connecting pipe 27 has an intermediate n'! II 3
6 is rotatably extended. A clutch lever 37 is provided at the portion of the intermediate shaft 36 that protrudes toward the pushing head 25 side.
is fixed. The clutch lever 37 is held on both sides by the pushing head 25, and is held by the pushing head 25.
It is said that it can be immersed into the housing part 3B in 5. intermediate shaft 36
A driven nut 39 is attached to the portion that protrudes toward the holding member 31 side.
is fixed.

The driven nut 39 is provided with a substantially half-circumferential threaded portion 40, and under the action of the biasing force of a compression spring 41 that is supported on the back side by the holding member 31, the driven nut 39 always keeps the threaded portion 40 at the threaded engagement position side with the drive screw 20. is under pressure.

Further, the driven nut 39 is attached to both side wall portions 3 of the holding member 31.
4A and 34B in a slidable state, and the connecting pipe 2
7, it is integrated with the pushing head 25 in terms of the pushing force direction. (Note that the driven nut 39 is integrated with the pushing head 25 (!: pushing and pushing inward) via the intermediate shaft 36 and the clutch lever 3γ without using the holding member 31 and the connecting pipe 27. In other words, the clutch lever 37, the intermediate shaft 36, and the driven nut 39 are fixed to each other, so that the operating force that resists the urging force of the compression spring 41 is applied to the clutch lever 37.
When the clutch lever 37 is inserted into the housing portion 38 of the pushing head 25, the driven nut 39 rotates between the side walls 34A and 34B of the holding member 31 through the rotation of the intermediate shaft 36. However, the threaded portion 4o of the driven nut 39 is connected to the drive screw 2o.
It becomes possible to release the &B screw 2o, the driven nut 39, and the 9 connection Q, -.

Moreover, the screwing part 40 of the driven nut 39 is prevented from being removed from the clutch lever 37 by the biasing force of the pressure spring 41. : The clutch lever 37 is returned to the screwed position of
protrudes outward from. The threaded portion 40 of this driven nut 39
(!: When the drive screw 20 rotates under the threaded engagement with the drive screw 2o, the driven nut 39 rotates before the drive screw 2° rotates.
moves, and the pushing head 25, which is integrated with the driven nut 39 in the pushing direction as described above, also becomes movable in the pushing direction.

Note that an eave-shaped liquid receiving portion 42 is provided above the front insertion hole 29 of the cabinet 11, and the vertical wall portion 28
It is provided so as to protrude from the syringe holder 13 to prevent the liquid agent from falling into the insertion hole 29 from the syringe holding part 13 side. In the figure, 43 is a guide path for causing the liquid to fall to a lower position from the insertion hole 29, 44 is an external power input terminal, and 45 is a power switch.

Therefore, in this embodiment, the drive motor 19 and the drive screw 20 are connected via the following gear train.

That is, the drive gear 51 fixed to the output shaft 19A of the drive motor 19 is supported at a predetermined position relative to the cabinet 11! 1. A driven gear 52 fixed on the support shaft 20A of the drive screw 20 is supported at a predetermined position relative to the cabinet 11. Support shaft 20A of drive screw 20
A swing plate 53, which is a movable plate in the present invention, is supported by. The swinging plate 53 is capable of swinging with respect to the cabinet 11 around the support shaft 20A. An intermediate gear 55 is supported on the rocking plate 53 via a support shaft 54 . The intermediate gear 55 is connected to the drive gear 51 and the driven gear 5 while the swing plate 53 remains in the meshing position where it contacts the pin 56 protruding from the cabinet 11.
It is said that it is possible to mesh with 2. Here, the rocker plate 53 is pressed toward the pin 56 under the action of a biasing force of a spring 57, which is supported on the back side of the cabinet 11 and serves as a holding means in the present invention. That is, the spring 57 can hold the swing plate 53 in the meshing position when the load acting on the pushing head 25 is less than a predetermined value. Furthermore, the cabinet 11 is provided with a swing plate 53 that moves from the meshing position when the load acting on the pushing head 25 exceeds the predetermined value. 11I"f'1S53
A microswitch 58 is provided as a detection means in the present invention, which can detect the movement of the swing plate 53 when pressed by A.

That is, when the load acting on the pushing head 25 reaches a predetermined value or more due to an abnormal increase in the internal pressure of the syringe 12, etc., and the driven gear 52 stops or reaches a deceleration state below a predetermined moving speed, the meshing with the driving gear 51 occurs. The intermediate gear 55, which continues to rotate at a predetermined rotational speed, begins to revolve around the subordinate l1rb gear 52 along with its rotation. This intermediate tooth] tL55 has no revolution, and the rocking plate 53 has a spring 5
7 from the meshing position while compressing the actuating portion 53.
The microswitch 58 is actuated by A, and the overload width acting on the pushing head 25 can be detected.

Note that the push head 2 that can be detected by the microswitch 58
The magnitude of the overload acting on 5 is as follows! l! Jra car 52
It is defined by the setting of the biasing force of the spring 57 that allows the surrounding intermediate gear 55 to revolve.

(2) Specific Effects of the Invention When using the syringe injection device 10 described above, the syringe 12 filled with a liquid agent is first held in the syringe holding portion 13. Here, the flange portion 14 of the syringe 12 is engaged with the engagement groove portion 15, and the outer cylinder portion 16 of the syringe 12 is held under pressure by the clamp arm 17. A liquid injection catheter is connected to the tip 12A of the syringe 12 held in this manner.

Next, by gripping the pushing head 25 and the Clara spring bar 37, an operating force that resists the biasing force of the compression spring 41 is applied to the clutch lever 37, and the clutch lever 37 is retracted into the housing portion 3B+19. . This clutch lever 3
7 into the accommodating portion 38, the connection state between the drive screw 20 and the driven nut 39 is released as described above. is moved along the slide groove 23, and the pushing head 25 is set to the pushing start position with respect to the pusher 24 of the syringe 12.

Next, the operating force applied to the clutch lever 37 is removed, and the threaded portion 40 of the slave nut 39 is returned to the screwed position with the drive screw 20 by the biasing force of the compression spring 41, and the driven nut 39 is connected to the drive screw 2o. Further, in order to drive the drive motor 19, the driven nut 39 is connected to the driven nut 39 through the screw engagement between the driven screw 2o and the driven nut 39, which rotate at a predetermined speed.
The pushing head 25 integrated with the pusher 9 moves at a predetermined speed, and the pusher 24 of the syringe 12 can be pushed at a predetermined pushing speed, so that the liquid in the syringe 12 is kept in a predetermined position for a long time. can be injected into thoughts at an injection rate of

Under the above-mentioned injection operation conditions, the liquid transport pipe connected to the tip 12AJζ of the syringe 12 may bend and become non-conducting, or the patient side light of the liquid transport pipe may be bent, and the injection pipe connected to the end of the liquid transport pipe may be If the internal pressure of the syringe 12 increases abnormally due to a closed group in the needle, or if the pusher 24 becomes unable to move due to deformation of the syringe 12, the load acting on the pushing head 25 reaches a predetermined value or more. Driven gear 52
When it stops or reaches a deceleration state below a predetermined moving speed, the swinging plate 53 swings as described above, and its actuator 53A operates the microswitch 5B, causing the pushing head 2
It becomes possible to quickly detect an overload condition acting on the motor 5 and notify the authorities of the occurrence of an abnormal condition.

Therefore, according to this embodiment, it is possible to detect the occurrence of an abnormality in the injection operation under the condition that the load torque of the drive motor 19 is always below the rated torque, and the life of the drive motor 19 is not shortened. . Further, it is possible to quickly detect the occurrence of an abnormality in the injection operation without requiring a complicated electrical control circuit for detecting the occurrence of an abnormality in the injection operation.

Note that the present invention includes the armpit 11 + motor 19 and pushing head 25.
If the gear train consisting of at least the three drive gears 51, driven gear 52, and intermediate gear 55 is interposed in the power transmission path between the It's okay.

Furthermore, the detection means in the present invention is not limited to the microswitch 58 described above, but may also be a photoelectric switch, a reed switch, or the like.

■ Specific Effects of the Invention As described above, the present invention provides a syringe pusher that is held in a syringe holding section on the cabinet by a push head that is movable by the rotational force of a drive motor that is identified in the cabinet. A syringe injection device capable of pushing a syringe includes a drive gear supported at a predetermined position relative to the skeleton cabinet and capable of being interlocked with the drive motor, and a drive gear supported at a predetermined position relative to the cabinet and capable of interlocking with the cough pushing head. a driven gear supported by the movable plate so as to be movable along a predetermined path with respect to the cabinet; and a driven gear supported by the movable plate, and the drive gear and an intermediate gear capable of meshing with the driven gear; a holding means for retaining the movable plate at the meshing position when the load acting on the pushing head is less than a predetermined value; and the pushing head. The overload detection mechanism includes a detection means for detecting movement of the movable plate from the meshing position when the load acting on the movable plate exceeds a predetermined value. It is possible to quickly detect the occurrence of an abnormality in the injection operation while minimizing the load torque acting on the injection valve.

Further, in the syringe injection device according to the present invention, since the holding means is a spring, it becomes possible to easily set the overload detection point to an arbitrary state by adjusting the spring constant.

Further, in the syringe injection device according to the present invention, the movable plate is a rocking plate whose rocking center is the rotation center of the driven gear, so that the driven gear and the intermediate gear are always kept in mesh. By reducing the gear meshing that occurs when overload is detected to only the 8 drive gear and the intermediate gear, when the motor restarts, the drive gear and the intermediate +i wheel mesh with each other and can be driven with a slight rotation of the motor.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional syringe injection device;
2 is a plan view of FIG. 1, FIG. 3 is a sectional view showing a syringe injection device according to an embodiment of the present invention, FIG. 4 is a sectional view taken along the fV-fV line in FIG. The figure is a cross-sectional view taken along the line ■-■ in Figure 3, Figure @6 is a cross-sectional view taken along the line ■-vt in Figure 3, Figure 7 is a cross-sectional view taken along the line ■-■ in Figure 3, FIG. 8 is a perspective view showing the syringe injection device. 10... Syringe injection device, 11... Cabinet, 12... Syringe, 13... Syringe holding 5, 19... Drive motor, 25... Pushing head, 5
DESCRIPTION OF SYMBOLS 1... Drive gear, 52... Driven gear, 53... Rocking plate, 55... Intermediate pawl, 57... Spring, 58...
·Microswitch. Patent Applicant Terumo Corporation Representative Patent Attorney Osamu Shiokawa Figure 1 Figure 2

Claims (3)

[Claims] (1) In a syringe injection device in which a syringe pusher held in a syringe holder on a cabinet can be pushed by a pushing head that is movable by the rotational force of a drive motor fixed to the cabinet, the core A driving gear supported at a predetermined position relative to the cabinet and capable of interlocking with the drive motor; a driven pawl supported at a predetermined position relative to the cabinet and capable of interlocking with the pushing head; A movable plate supported to be movable along a predetermined path; and a movable plate supported by the movable plate and capable of engaging the drive gear and the driven gear in a state in which the movable plate remains in a meshing position. an intermediate float for holding the movable plate in the meshing position when the load acting on the pushing head is below a predetermined value; A syringe injection device characterized by having an overload detection mechanism comprising a detection means for detecting movement of the movable plate from the meshing position when the movable plate moves from the meshing position. (2) Claim 1, wherein the holding means is a spring.
Syringe injection device as described in Section. (3) The syringe injection device according to claim 1 or 2, wherein the movable plate is a oscillating plate whose oscillation center is the rotation center of the driven gear.