JP2003180828A - Electric fluid discharging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric fluid transfusion apparatus which has simple mechanism, discharges a fluid electrically, and is reliably and safely operated in particular. <P>SOLUTION: A linear motor 5 as a driving means for discharging the medical fluid 2a, a battery 8 for feeding power to this linear motor 5, and a control part 9 for controlling the driving operation of this linear motor 5 are provided in a casing 1. A piston 2b is pressurized by one end of an inner yoke 5a which is the movable part of the linear motor 5 via a plunger rod 7 to discharge the medical fluid 2a from an injection needle 10. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric fluid discharge device that controllably discharges a fluid enclosed in a cylinder.

[0002]

2. Description of the Related Art Conventionally, an electric injection device has been known as an example of an electric fluid ejection device. A typical electric injection device uses a motor with a speed reducer as a driving means, and its rotation operation is performed by a pinion gear and a rack. Is converted into a linear motion by, and the piston in the cartridge is pushed to eject the injection liquid from the injection needle pierced at the tip of the cartridge (for example,
(See Utility Model Registration No. 2530150).

As a power-type handheld injection device, a motor with a speed reducer is used in the same manner as described above to drive a piston of an injector detachably connected to a casing, and a parent device for converting its rotational operation into linear operation. It is equipped with a screw (for example, see JP-A-6-7440).

These electric injection devices drive the piston by controlling the rotation speed and rotation direction of the motor.

Further, when the electric injection device does not function due to the power interruption, it is necessary to manually operate the plunger rod, and it is necessary to release the connection of the mechanism for converting the rotation operation of the drive motor into the linear operation.

[0006] Further, in the self-injection used directly by the patient,
Since a manual cartridge type or a disposable type syringe is used and the electric injection device is used for a long period of time, it is necessary to ensure safety and reliability.

[0007]

However, each of the above-mentioned conventional electric injectors uses a rotary motor and requires a mechanism for converting a rotary motion into a linear motion.

Further, in the power-type hand-held injection device, a small and lightweight DC motor with a brush is generally used, and the desired thrust is obtained by decelerating with a speed reducer.

For this reason, a mechanism for converting to a linear motion and a speed reduction mechanism are required, and the mechanism is complicated.

Further, in order to enable manual discharge when electric discharge cannot be performed due to battery exhaustion, it is necessary to disconnect the conversion mechanism (rotation operation to linear operation), and a complicated latch mechanism is required. Met.

Further, the DC motor with a brush is easily affected by the problem of wear due to wear between the brush and the commutator, and the use of a battery as a driving power source results in a small current capacity when the resistance value of the sliding portion is large. . As described above, the brush DC motor is easy to handle, but has a problem in reliability.

The present invention has been made to solve such a conventional problem, and an object thereof is to provide a device which has a simple mechanism and is capable of electrically discharging a fluid, and particularly an electrically-operated injection device which is highly reliable and can be operated safely. To aim.

[0013]

In order to solve the above-mentioned problems, the electric fluid discharge device of the present invention comprises a piston for discharging a fluid in a cylinder and a movable part of a linear motor connected to the piston.

Further, a linear motor is used as a driving means for discharging the liquid contained in the cylinder of the syringe or the liquid medicine cartridge.

[0015]

In order to solve the above problems, an electric fluid discharge device according to a first aspect of the present invention is such that a movable part of a linear motor is connected to a piston for discharging a fluid in a cylinder.

The electric injection device according to a second aspect of the invention uses a linear motor as a driving means for discharging the liquid contained in the cylinder of the syringe or the liquid medicine cartridge.

In the electric injection device according to a third aspect of the present invention, a cylindrical casing, a drug solution cartridge detachably connected to a front end portion of the casing, and a piston provided in the drug solution cartridge up to the tip of the cartridge. It is provided with a plunger rod for discharging the pushed-in chemical liquid and a linear motor for driving the plunger rod.

Further, the electric injection device according to a fourth aspect of the invention is provided with a protrusion projecting to the outside of the casing connected to the linear motor movable part on the side opposite to the plunger rod, and the drug solution is manually passed through the protrusion. It is possible to discharge or to pull back the pushed piston.

Further, in the electric injection device according to the present invention, a battery for supplying electric power to the linear motor and a control unit for controlling the drive amount of the linear motor are provided in the casing, and the operation unit is provided on the outer surface of the casing. The arbitrary discharge amount is set by the operation section.

Furthermore, the electric injection device according to claim 6 is
It uses an insulin preparation capable of self-injection.

As described above, the piston for discharging the liquid in the cylinder is connected to the movable portion (thrust) of the linear motor to drive in the linear direction, and the conversion mechanism for converting the conventional rotary operation into the linear operation and the deceleration. The mechanism can be eliminated, and the electric liquid ejection device can be downsized.

Further, since the drive system does not have a speed reduction mechanism or a conversion mechanism, even when electric drive is not possible, the protrusion protruding to the outside of the casing allows manual operation, thus ensuring the safety of the syringe.

Further, the position control and the speed control of the linear motor can be set by the operation portion, and the liquid discharge amount can be controlled to be constant.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) Embodiment 1 is an electric injection device as a typical example of an electric fluid ejection device, which comprises a casing for accommodating an electric drive unit for ejecting a drug solution and a cartridge holder for accommodating a drug solution cartridge. Composed.

In FIG. 1, 1 is a casing of the electric injection device main body, 2 is a liquid medicine cartridge, 3 is a cartridge holder for holding the liquid medicine cartridge, 4 is a fixing portion for detachably connecting the liquid medicine cartridge, and 5 is a linear drive means. Reference numeral 6 is a motor, 6 is a supporting member for a movable portion of the linear motor, 7 is a plunger rod, 8 is a battery as a power source, and 9 is a controller for controlling the driving of the linear motor to set the discharge amount.

The casing 1 and the chemical liquid cartridge 2 can be detachably fitted, and the cartridge holder 3 has a fixing portion 4 which is detachably connected to the casing 1 on the base end side. Is fixed to the casing 1. Further, the chemical liquid 2a is enclosed in the chemical liquid cartridge 2, and the piston 2b is provided on the proximal side.
A septum made of rubber is attached to the distal end side, and the injection needle 10 is attached to the septum for use.

In the casing 1, there are provided a linear motor 5 as a driving means for discharging the chemical liquid 2a, a battery 8 for supplying electric power to the linear motor 5, and a controller 9 for controlling the driving operation of the linear motor 5. I have it.

Here, the linear motor 5 and its peripheral mechanism will be described. The linear motor 5 includes a cylindrical inner yoke 5a, a movable portion provided with magnets 5b and 5c each having an outer peripheral surface having a single pole and adjacent polarities opposite to each other, and a cylindrical outer yoke 5d. It is roughly divided into a fixed portion provided with fixed windings 5e and 5f, and is opposed to each other at a peripheral surface with a constant gap, and both ends of the inner yoke 5a are slidably supported by support members 6a and 6b. ing.

The radial main magnetic flux emitted from the N pole of the outer peripheral surface of the magnet 5b enters the opposing outer yoke 5d through the gap, further passes through the outer yoke 5d, and reaches the S pole of the outer peripheral surface of the adjacent magnet 5c. Reach On the other hand, the magnet 5
The radial main magnetic flux emitted from the N pole of the inner peripheral surface of c is the inner yoke 5a.
It is a closed magnetic path that passes through the inside and returns to the S pole of the inner peripheral surface of the adjacent magnet 5b.

When currents in opposite directions are applied to the windings 5e and 5f which are in an interlinking state with the main magnetic fluxes of the magnets 5b and 5c, the windings 5e and 5f generate thrust in the same direction.

The driving stroke is determined by the dimensional difference in the moving direction of the winding and the magnet, and the magnet is set longer. However, the magnet 5b and the magnet 5c are brought close to each other, and the winding 5e and the winding 5f are substantially stroked. Place them with a space between each other.

Then, one end of the inner yoke 5a, which is a movable portion, presses the piston 2b through the plunger rod 7 to discharge the drug solution 2a from the injection needle 10.
A linear sensor 13 is attached to the other end of the inner yoke 5a to control the operating speed and the operating position of the inner yoke 5a. Further, limit switches 11 and 12 for detecting the movement limit of the inner yoke 5a of the movable portion are provided, and when the piston 2b is at the tip position of the chemical liquid cartridge 2, the limit switch 11 and the plunger rod 7 are When the chemical liquid cartridge 2 returns to the base end position, the limit switch 12 operates to stop the power supply to the linear motor 5.

On the outer surface of the casing 1, there is provided an operation panel section 9a for setting the discharge amount of the electric injection device, a forward drive switch SW1 and a backward drive switch SW2 to form an operation section (FIG. 2). . The operation panel section 9a is connected to the control section 9, and the stroke and moving speed of the linear motor 5 can be arbitrarily set, and the discharge amount can be set.

Here, the operation of the electric injection device when a general patient himself injects insulin will be described. First, the patient attaches the injection needle 10 to the tip of the drug solution cartridge 2, attaches the drug solution cartridge 2 filled with the insulin preparation to the casing 1, turns the injection needle 10 upward, and turns on the forward drive switch SW1. The piston 2 is linked to the plunger rod 7 by the movable part of the piston 2.
b is pushed in, and excess air and liquid medicine 2a are injected into the needle 1.
Discharge from 0.

Here, when the chemical liquid 2a is slightly discharged, the forward drive switch SW1 is turned off, and the stroke and drive speed for one operation are initialized by the operation panel section 9a. Next, when the forward drive switch SW1 is turned on, the stroke drive for one stroke is performed. After that, it can be used a plurality of times (or once) until the limit switch 11 is actuated by the stroke.

On the other hand, when the backward drive switch SW2 is turned on while the forward drive switch SW1 is off, the mover of the linear motor 5 moves in the opposite direction. At this time, the suction operation is performed if the plunger rod 7 and the piston 2b are connected, but normally, the chemical liquid cartridge 2 is usually disposable, and the plunger rod 7 and the piston 2 are usually used.
b is not connected. Further, in the case of the suction operation, it can be controlled at the moving speed set by the operation panel portion 9a as in the case of the discharging operation, and moves until the limit switch 12 is activated.

As described above, since the piston is directly driven by the thrust of the linear motor, a mechanism for converting the rotary motion into the linear motion is not required, and the mechanism is simple and the device can be downsized. Further, an arbitrary discharge amount can be set by the operation unit.

(Embodiment 2) Embodiment 2 can be used even in an emergency such as when Embodiment 1 does not function due to power cutoff (for example, battery exhaustion), and a description will be made focusing on a mechanism that enables manual drive. .

In FIG. 3, 31 is a casing of the electric injection device main body, 32 is a liquid medicine cartridge, 34 is a fixed part of the casing, 35 is a linear motor of driving means, 37 is a plunger rod, 38 is a battery, 39 is a linear motor. Is a control unit that controls the drive of the control unit to set the discharge amount, 40 is an injection needle, 43 is a manual rod of a protrusion, and 44 is a protective cover.

On the side opposite to the fixed portion 34 of the casing 31, there is provided a hole through which the manual rod 43 penetrates, and one end of the manual rod 43 penetrates this hole and is connected to the movable part of the linear motor 35. There is.

The manual rod 43 is a disk-shaped head 43a.
And is projected to the outside of the casing 31.
Further, when used manually, the protective cover 44 can be removed from the casing 31 and used. Also,
The length of the manual rod 43 protruding from the casing 31 is
It has a length enough to push the piston in the chemical liquid cartridge 32 to the tip.

Normally, the linear motor 35 is drive-controlled by the control unit 39 as in the first embodiment. However, the linear motor 35 is cut off by the power supply from the battery 38 or the battery 38 is exhausted and the supply voltage is insufficient. When the head cannot be driven, the head 43a of the manual rod 43 is manually operated as an emergency measure so that the liquid medicine in the liquid medicine cartridge 32 is discharged from the injection needle 40 or the movable portion of the linear motor 35 is returned to its original position. Can be returned.

Since the linear motor 35 is driven without the need for a speed reducer or a linear conversion device as in the prior art, it is not necessary to provide a mechanism for releasing the connection, and the manual rod 43 can be directly operated. The safety of can be secured.

It should be noted that the piston of another cylinder and the movable part of the linear motor may be connected instead of the electric injection device for medical use. For example, it can be applied as a device (dispenser) that discharges and applies a certain amount of adhesive, and is not limited to the electric injection device for medical use, but also as an electric fluid ejection device that ejects other fluids. Available.

[0046]

As is apparent from the above embodiments, according to the inventions of claims 1 to 3, since the fluid in the cylinder is discharged by the thrust of the linear motor, there is provided a mechanism for converting the rotary motion into the linear motion. It is unnecessary, the electric fluid discharge mechanism can be simplified, and the device can be downsized.

According to the invention described in claims 4 and 6,
Even when the electric drive is not possible, the protrusion provided outside the casing allows manual operation, and the safety of the self-injection of insulin performed by the patient can be secured.

Further, according to the invention of claim 5, since the battery, the control portion and the operation portion are provided on the outer surface in the casing, the discharge amount and the discharge speed of the liquid can be arbitrarily set and controlled. An injection device is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of an electric injection device according to a first embodiment of the present invention.

FIG. 2 is an external perspective view of the electric injection device according to the first embodiment of the present invention.

FIG. 3 is a sectional view of an electric injection device according to a second embodiment of the present invention.

[Explanation of symbols]

1,31 casing 2,32 Chemical cartridge 2a drug solution 2b piston 5,35 linear motor 5a, 5b, 5c movable part 7 Plunger rod 8,38 batteries 9,39 Control unit 9a Operation part (operation panel part) 43 Projection (manual rod)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koichi Kinashi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F term (reference) 3H075 AA09 BB03 CC35 CC36 DB03                       DB49                 4C066 BB01 CC01 DD11 HH02                 4C077 AA08 JJ04 JJ08 JJ27

Claims (6)

[Claims] 1. An electric fluid discharge device in which a movable part of a linear motor is connected to a piston for discharging a fluid in a cylinder. 2. An electric injection device using a linear motor as a driving means for discharging a liquid contained in a cylinder of a syringe or a liquid medicine cartridge. 3. A cylindrical casing, a liquid medicine cartridge detachably connected to a front end portion of the casing, and a plunger rod for pushing a piston provided in the liquid medicine cartridge to a cartridge tip to discharge the liquid medicine. The electric injection device according to claim 2, further comprising a linear motor that drives the plunger rod. 4. A protrusion, which protrudes outside a casing connected to a linear motor movable part on the side opposite to the plunger rod, is used to manually discharge the chemical solution or pull back the pushed piston. The electric injection device according to claim 3, which makes it possible. 5. A battery for supplying electric power to a linear motor and a control unit for controlling a drive amount of the linear motor are provided in a casing, and an operation unit is arranged on an outer surface of the casing, and an arbitrary discharge amount is set by the operation unit. The electric injection device according to claim 3 or 4, which is set. 6. The electric injection device according to claim 2, wherein an insulin preparation capable of self-injection is used.