JP2023069190A - linear motor - Google Patents

Abstract

To provide a linear motor capable of performing two-stage extension operation.SOLUTION: A linear motor (500) includes: a stator (510); movable elements (520;530) movably arranged along a center axis (CA) with respect to this stator. The movable elements are comprised of: a first movable element (520); and a second movable element (530) that is movably arranged along the center axis (CA) with respect to the first movable element. Each of the stator (510), the first movable element (520), and the second movable element (530) may have a shape which is actually rotation symmetry with respect to the center axis (CA). The second movable element (530) has the center axis (CA) and a column-like shape arranged near the center axis (CA), and the first movable element (520) has a cylindrical shape arranged near an outer periphery of the second movable element. The stator (510) may have a cylindrical shape arranged near the outer periphery of the first movable element.SELECTED DRAWING: Figure 7

Description

The present invention relates to linear motors, and more particularly to linear motors used in injector modules such as injection devices.

2. Description of the Related Art Conventionally, various medical robot devices have been developed. In particular, vaccination is recommended in order to prevent the novel coronavirus infection (COVID-19), which is spreading all over the world these days. Such vaccinations are administered sequentially to a large number of people using syringes at a given vaccination site. Therefore, there is a demand for a robot device that can automatically perform such vaccination without human intervention. As is well known, this vaccination involves intramuscular injection. Here, "intramuscular injection" refers to a method of directly injecting a drug such as a vaccine into the muscle located deep within the subcutaneous fat.

For example, US Pat. No. 6,200,009 discloses a disposable syringe that can be used in vaccination regimens. The disposable syringe includes a housing, a push rod body, a drug chamber, an injection needle, and an injection moving means (biasing means). The housing has an axis extending from a distal end to a proximal end and a proximal skin-contacting wall that abuts the injection site. The contact wall is provided with an opening for receiving an injection needle. The pushrod body has a pressure surface facing proximally toward the skin-contacting wall and is arranged to move between a first proximal position and a first distal position. The pushrod body is axially movable within the housing between a first distal position, an intermediate position, and a first proximal position. A drug chamber is positioned between the pressure surface and the proximal skin-contacting wall. The drug chamber is axially movable and non-axially depressed by moving the pushrod body toward the proximal end. An injection needle is attached to the drug chamber and arranged for axial movement between a third distal position and a third proximal position. An injection moving means (biasing means) is configured to move the pushrod body from a first distal position to a first proximal position.

In the above disposable syringe, the pushrod body, medicament chamber, and injection needle are configured such that the pushrod body moves from a first distal position to an intermediate position and the injection needle moves from a third distal position to a third proximal position. When the proximal end of the injection needle protrudes distally from the skin contact wall, and when the push rod body moves to the first proximal position, at least a portion of the liquid in the drug chamber reaches the injection needle. The medicament chamber is urged so as to be pushed out of the proximal end, moving the injection needle from a third proximal position to a third distal position.

However, in such a disposable syringe, a user (medical worker) can retract the push rod body from the first proximal position to the first distal position against the biasing force of the biasing means. need to let That is, since this disposable syringe requires manual intervention, it is not suitable for use as an injection device for incorporation into a robotic device that can be administered automatically.

Also, US Pat. No. 6,300,000 discloses an auto-injector for rapid release of a bolus of injectable medicament. This auto-injector has small outer dimensions and a generally flat, sealed housing that resembles a credit card. A syringe, configured to be contained within the flat housing, is pre-filled with a medicament. The housing contains a mechanism that, when triggered, automatically moves the syringe and needle forward to the injection position, compressing the volume of the syringe and causing a rapid injection. The forward injection end of the device contains an actuator that keeps the needle hidden and protected at all times, preventing post-injection hazards. The planar surface of the device has graphical symbols and other visual indicia related to the operation and conditions of the device. The device allows a simple three-step operation, reducing the risk of misuse.

In the auto-injector described above, the housing interacts with the cover and the peelable elongated strip. The device includes an actuator assembly and a syringe carrier assembly. The actuator assembly includes a generally flat needle shield and a pair of arms extending rearwardly from the shield. The actuator assembly is held in the retracted position by a pair of releasable arm locks. The actuator assembly is biased forwardly by a pair of longitudinally disposed side compression springs. The syringe has a flat configuration and is defined by a flat piston-type device with a cup-shaped container. The open end of the cup-shaped container receives a piston carrying an injection needle. The forward end of the piston includes a needle carrier by which an injection needle is held in spaced alignment with the septum. The needle carrier includes a longitudinally collapsible, forwardly extending, bellows-like support. The needle is secured to an anchor embedded with a portion of the needle within the needle support. The syringe assembly is biased by a syringe compression spring (drive spring). The needle support rests on the posterior surface of the needle shield when the needle penetrates the tissue to the intended depth. A detent opening is formed in each of the arms behind the opening.

An auto-injector configured in this manner operates as follows. After removing the peelable elongated strip and cover, the needle shield of the actuator assembly is pressed against the patient's skin such that the syringe carrier is centrifugally moved from its latched position under the bias of a drive spring with sufficient force. Driven off, the needle penetrates the skin and penetrates the tissue to the intended depth. When the needle support contacts the posterior surface, the sharp forward end of the needle penetrates the patient's tissue to the intended depth. The continued biasing force of the drive spring advances the syringe carrier and container over the then stationary piston, collapsing the volume within the syringe and causing a bolus of medication to be injected into the patient. The injection ends when the volume of the syringe ceases to be compressed. As the injection stroke nears its end, the arm lock is released. As the actuator assembly arm is freed, the actuator assembly advances relatively forward of the housing under the bias of the side springs so that the device is retracted. A needle shield extends to cover and protect the forward end of the needle, and an arm lock is dropped into the rear opening to lock the actuator assembly and needle shield in a centrifugally extended needle protection configuration. When the needle shield is extended to its centrifugally locked position, the biohazard indicia on the flat surface of the shield are prominently exposed to perform their warning function.

However, the auto-injector with such a configuration is not for use by medical personnel, but for individual use by the patient himself/herself. Accordingly, such auto-injectors are not intended for use as vaccination syringes for use at vaccination venues such as those described above. Also, including the actuator inside it, the auto-injector has a very complicated construction. Therefore, the injection device to be incorporated into the above-mentioned robot device is configured so as to simplify the configuration of the syringe itself and use an actuator (hereinafter referred to as an "external actuator") provided outside the syringe. is desirable.

Various actuators are conceivable as such an external actuator, and for example, a linear motor can be used. There are various types of linear motors, but when a large driving force is not required, they are often composed of a combination of permanent magnets and coils. Also, as is well known, linear motors are roughly classified into two types: "moving magnet type linear motors" and "moving coil type linear motors".

A moving magnet linear motor includes a permanent magnet as a mover and a coil (exciting coil) as a stator (see, for example, Patent Documents 3, 4, 5, 6, and 7).

On the other hand, a moving-coil linear motor includes a coil (armature coil) as a mover and a permanent magnet as a stator (for example, Patent Documents 8 and 9).

The principle of operation of both the moving magnet type linear motor and the moving coil type linear motor is the interaction between the magnetic flux generated from the permanent magnet and the current flowing through the coil (so-called Fleming's left-hand rule). It utilizes the thrust generated by In other words, any known linear motor consists of one stator and one mover movably arranged relative to the stator along the central axis.

Japanese Patent Publication No. 2016-517742 U.S. Pat. No. 6,979,316 Japanese Patent No. 2781912 JP-A-2001-086725 JP 2009-050128 A Japanese Patent No. 5068494 Japanese Patent No. 4068848 Japanese Patent No. 3852117 Japanese Patent Application Laid-Open No. 2007-209176

However, when the well-known linear motor as described above is used as an external actuator provided outside the syringe, the following problems arise.

Specifically, the known linear motor described above can only move one mover relative to the stator along the central axis. That is, only one driven body associated (coupled or abutted) with one mover is moved along the central axis. In other words, known linear motors are only capable of simple stretching movements, moving only one driven body.

On the other hand, when attempting to perform the intramuscular injection described above, it is necessary to use an external actuator to cause the syringe to perform at least the following three steps (first step, second step, third step). There is The first step is a step of projecting the injection needle from the front surface of the housing of the syringe and causing the tip of the injection needle to reach the human muscle (hereinafter referred to as "injection needle projecting step"). The second step is the step of pushing out the drug solution from the tip of the injection needle into the muscle (hereinafter referred to as the "drug solution extrusion step"). The third step is a step of retracting the projected injection needle into the housing of the syringe (hereinafter referred to as an "injection needle retraction step"). That is, as the external actuator for the syringe, at least two different driven bodies, a first driven body for moving only the injection needle and a second driven body for pushing out the drug solution, are moved. need to let In other words, as an external actuator for the syringe, a linear motor capable of at least a two-stage extension movement is required.

However, as described above, with known linear motors, it is difficult to perform at least a two-stage stretching operation that moves a plurality of driven bodies.

An object of the present invention is to provide a linear motor capable of performing a two-stage stretching operation.

According to one aspect of the present invention, in a linear motor including a stator; and a second mover movably arranged along the central axis with respect to the first mover.

In the linear motor, each of the stator, the first mover, and the second mover may have a shape substantially rotationally symmetrical with respect to the central axis.

Also, the second mover has a cylindrical shape arranged on and near the central axis; the first mover has a cylindrical shape placed near the outer periphery of the second mover. the stator may have a cylindrical shape disposed near the outer periphery of the first mover;

The first mover may have an annular cross-sectional shape and include a plurality of permanent magnets arranged along the central axis. In this case, the plurality of permanent magnets generate outer magnetic flux and inner magnetic flux to their outer and inner peripheral parts, respectively. The stator may include a plurality of outer electromagnet coils arranged continuously along the central axis so as to surround the first mover via an outer gap with respect to the first mover. In this case, the interaction between the outer current flowing through the plurality of outer electromagnet coils and the outer magnetic flux allows the stator to move the first mover along the central axis. The second mover includes a plurality of inner electromagnet coils arranged continuously along the central axis so as to be surrounded by the first mover via an inner gap with respect to the first mover. OK. In this case, the second mover can travel along the central axis with respect to the first mover due to the interaction between the inner current flowing through the plurality of inner electromagnet coils and the inner magnetic flux.

Furthermore, the stator may include an outer U-phase coil, an outer V-phase coil, and an outer W-phase coil that are star-connected as the plurality of outer electromagnet coils. Similarly, the second mover may include an inner U-phase coil, an inner V-phase coil, and an inner W-phase coil that are star-connected as the plurality of inner electromagnet coils. In this case, the linear motor consists of a three-phase linear motor.

Each of the plurality of permanent magnets has a length three times the length of the coil of each phase, and the plurality of permanent magnets are arranged in series along the central axis such that adjacent magnetic poles are in close contact with each other. preferably combined.

The mover may be configured to move in the first direction along the central axis with respect to the stator when an outer current is applied to the plurality of outer electromagnet coils of the stator. Similarly, the second mover moves in the first direction along the central axis with respect to the first mover when an inner current is passed through the plurality of inner electromagnet coils of the second mover. may be configured to In such a configuration, the linear motor has first biasing means for biasing the mover in the second direction opposite to the first direction when the flow of the outer current is stopped. and second biasing means for biasing the second mover in the second direction when the flow of the inner current is stopped.

The linear motor has a base arranged parallel to the central axis; a guide rail attached on the base parallel to the central axis; first and second brackets respectively held at ends in a second direction opposite to the first direction; and slidably provided on the guide rails, from the first and second brackets respectively to the first brackets. first and second sliding members that hold the first mover at its opposite ends at positions spaced apart in the (1) direction and the second direction.

The linear motor comprises: another bracket having an opening erected on the base on the first direction side relative to the first bracket; a hollow first operation part extending to and capable of passing through an opening of another bracket; extending from the end of the second armature in the first direction along the central axis in the first direction; and a second operation part inserted into the first operation part with a space therebetween.

In the linear motor, the first urging means may be arranged between the first sliding member and another bracket, and the second urging means may be positioned closer to the first sliding member than the first sliding member. It may be arranged in a space formed on the second direction side and on the inner peripheral side of the first mover.

According to the linear motor of the present invention, it is possible to perform a two-stage stretching operation by moving two different driven bodies.

1 is a perspective view of the appearance of an automatic vaccination robot device to which the present invention is applied, together with a person to be vaccinated, viewed obliquely from the front right. 2 is a schematic right side view of the appearance of the automatic vaccination robotic device shown in FIG. 1, together with a person to be vaccinated, viewed from approximately the right; FIG. Fig. 2 is a perspective view of the appearance of the automatic vaccination robot device shown in Fig. 1, together with a person to be vaccinated, viewed obliquely from the right rear; Fig. 2 is a perspective cross-sectional view of a cartridge injector operated by an external actuator used as a linear motor according to the present invention, viewed obliquely from the front right; FIG. 5 is a schematic right side cross-sectional view of the cartridge injector shown in FIG. 4 as seen from the substantially right side; FIG. 5 is a perspective cross-sectional view of the cartridge injector shown in FIG. 4 as seen obliquely from the right rear; 1 is a perspective cross-sectional view of a linear motor according to an embodiment of the present invention, seen obliquely from the front right, together with a cartridge injector arranged in an operation portion; FIG. FIG. 8 is a schematic right side cross-sectional view of the linear motor illustrated in FIG. 7 together with a cartridge injector disposed in the operation section, viewed from the substantially right side; FIG. 8 is a perspective cross-sectional view of the linear motor illustrated in FIG. 7 as viewed obliquely from the rear right, together with a cartridge injector disposed in the operating portion; FIG. 10 is a cross-sectional view for explaining magnetic flux generated by a plurality of permanent magnets of a first mover used in the linear motor shown in FIGS. 7 to 9; An example of connection between each coil and a control driver when nine coils are used as electromagnet coils for the stator and the second mover used in the linear motor shown in FIGS. 7 to 9 will be described. It is a diagram for

(An example of a device to which the present invention is applied)
To facilitate understanding of the present invention, an automatic vaccination robot device 100, which is a type of medical robot device, will be described as a device to which the present invention is applied. This automatic vaccination robot device 100 is a robot device that automatically performs vaccination to prevent infectious diseases such as novel coronavirus infectious disease (COVID-19).

1-3 are diagrams showing the appearance of an automatic vaccination robotic device 100 together with a person 200 to be vaccinated. FIG. 1 is a perspective view of the appearance of the automatic vaccination robot device 100 as viewed obliquely from the front right. FIG. 2 is a schematic right side view of the appearance of the automatic vaccination robot device 100, viewed from the substantially right side. FIG. 3 is a perspective view of the appearance of the automatic vaccination robot device 100 as seen obliquely from the rear right.

Here, a Cartesian coordinate system (X, Y, Z) is used as shown in FIGS. In the state shown in FIGS. 1 to 3, in the orthogonal coordinate system (X, Y, Z), the X-axis direction is the front-rear direction, the Y-axis direction is the left-right direction orthogonal to the X-axis direction, and the Z-axis direction. is the vertical direction orthogonal to the X-axis direction and the Y-axis direction. Therefore, the X-axis direction extends in the forward direction X1 and the rearward direction X2, the Y-axis direction extends in the right direction Y1 and the left direction Y2, and the Z-axis direction extends in the upward direction Z1 and the downward direction Z2. In this specification, the forward direction X1 is also called the forward direction or the advancing direction, and the backward direction X2, which is the direction opposite to the forward direction X1, is also called the reverse direction or the backward direction. It should be noted that the Cartesian coordinate system (X, Y, Z) will be used in the subsequent drawings as well. Also, in this specification, the forward direction X1 is also called the "first direction", and the rearward direction X2 is also called the "second direction". In this specification, "front" and "rear" may be appropriately called "first" and "second", respectively.

As is clear from FIGS. 1 to 3, at the position (inoculation position) in the front direction X1 of the automatic vaccination robot device 100, the person 200 who is the recipient is facing the right direction Y1, and is sitting in a chair. I'm sitting on the 300. In other words, in the illustrated example, the automated vaccination robotic device 100 is a device that vaccinates the human 200 from the left upper arm 210 by intramuscular injection.

The automated vaccination robotic device 100 includes a base 110 , first through fourth arms 121 , 122 , 123 and 124 and an injector module 130 . The first to fourth arms 121 to 124 are arranged in this order from the base 110 in the upward direction Z1. An injector module 130 is attached to the upper end of the fourth arm 124 . In the illustrated example, the base 110 is fixed on the floor, but it may be a movable base configured to be movable on the floor in the X-axis direction and the Y-axis direction.

The base 110 incorporates a controller (not shown) and a power supply (not shown) for controlling the automatic vaccination robotic device 100 . Instead of incorporating a power supply, the automated vaccination robotic device 100 may be configured to receive power from an external power supply, either wired or wirelessly. The controller is also wired or wirelessly connected to an external computer (not shown). The controller receives various commands from the computer for operating the automated vaccination robotic device 100 . A controller controls the operation of the automated vaccination robotic device 100 according to various commands.

The base 110 and the first to fourth arms 121 to 124 are connected via first to fourth joints 141, 142, 143 and 144. As shown in FIG. Specifically, the lower end of the first arm portion 121 is rotatably connected to the upper surface of the base 110 via the first joint portion 141 . The upper end of the first arm portion 121 and the lower end of the second arm portion 122 are connected via the second joint portion 142 so as to be rotatable around the rotation axis of the second joint portion 142. there is The upper end of the second arm portion 122 and the lower end of the third arm portion 123 are connected via a third joint portion 143 so as to be rotatable around the rotation axis of the third joint portion 143. there is The upper end of the third arm portion 123 and the lower end of the fourth arm portion 124 are connected via a fourth joint portion 144 so as to be rotatable around the rotation axis of the fourth joint portion 144. there is The first to fourth joints 141 to 144 are driven by first to fourth motors (not shown), respectively. The first to fourth motors rotate the first to fourth joints 141 to 144, respectively, based on control signals sent from the controller.

An injector module 130 attached to the upper end of the fourth arm 124 is an injection device for inoculating a person 200 with a vaccine. That is, the injector module 130 operates as an injection device incorporated in the present automated vaccination robotic device 100 . The injector module 130 inoculates the upper left arm 210 of the person 200 according to the operation command sent from the controller, as will be described later.

The injector module 130 includes a first housing 131 that covers an external actuator (described later) and a second housing 132 that covers a plurality of cartridge injectors (described below) driven by the external actuator. The second housing 132 incorporates a magazine device (not shown) that can be loaded with a plurality of cartridge injectors.

Specifically, the second housing 132 incorporates a waiting room (not shown), a disposal room (not shown), and an operation unit (described later). The standby chamber holds and accommodates all of the plurality of cartridge injectors in the initial state. The waste chamber is for containing used cartridge injectors. The magazine device operates to sequentially feed a plurality of cartridge injectors one by one from the standby chamber to the operation section, and then retract the used cartridge injectors from the operation section to the disposal chamber. The magazine device performs the loading operation as described above in accordance with the loading command sent from the controller.

On the other hand, the cartridge injector fed into the operation section is operated by an external actuator, as will be described later, and operates to inoculate the left upper arm 210 of the person 200. FIG. In other words, the cartridge injector fed into the operating section functions as a simple syringe for intramuscular injection.

Next, with reference to FIGS. 4 to 6, the configuration of the cartridge injector 400 sent into the operation section will be described. FIG. 4 is a perspective cross-sectional view of the cartridge injector 400 as seen obliquely from the front right. FIG. 5 is a schematic right cross-sectional view of the cartridge injector 400 viewed from the substantially right side. FIG. 6 is a perspective cross-sectional view of the cartridge injector 400 viewed obliquely from the rear right.

As mentioned above, FIGS. 4-6 also use the same orthogonal coordinate system (X, Y, Z) as that shown in FIGS. 1-3. Since the orthogonal coordinate system (X, Y, Z) used has already been described in detail, its description is omitted for the sake of simplicity.

As is clear from FIGS. 4 to 6, the cartridge injector 400 has a substantially rotationally symmetrical shape with respect to the central axis CA extending in the front-rear direction X. As shown in FIG. Cartridge injector 400 includes a hollow housing 410 extending along central axis CA. Housing 410 is made of metal or resin. The housing 410 is substantially cylindrical with a first inner wall 411 of a first inner diameter Di1, open at the rear end. The housing 410 has a tapered distal end portion 412 in the forward direction X1. The housing 410 has a cylindrical opening 4121 with a diameter Da at its distal end portion 412, through which an injection needle (catheter) 420, which will be described later, can be protruded/retracted. The diameter Da is smaller than the first inner diameter Di1. The opening 4121 of the tip portion 412 is closed with silicone (not shown). Therefore, injection needle (catheter) 420 has a shape that can penetrate silicone.

Injection needle (catheter) 420 is provided in housing 410 so as to extend along central axis CA on the front direction X1 (first direction) side. The injection needle (catheter) 420 has a substantially cylindrical shape and its tip 421 is obliquely cut. A rear end portion 422 of an injection needle (catheter) 420 is held by a first movable body 430 via a holding member 440 .

The first movable body 430 is arranged in the housing 410 so as to be movable in the front-rear direction X while sliding on the inner wall 411 along the central axis CA. Specifically, the first movable body 430 has a rear end portion 432 on the rearward direction X2 (first direction) side, a front end portion 434 on the forward direction X1 (first direction) side, and a rear end portion 432 . and an intermediate portion 436 disposed between the front end portion 434 .

The rear end portion 432 has a cylindrical portion and four ridges projecting radially outward from the cylindrical portion in the upward direction Z1, the downward direction Z2, the right direction Y1, and the left direction Y2. The four ridges extend in the front-rear direction X. As shown in FIG. An outer peripheral surface that virtually connects radially outer tip surfaces of the four ridges of the rear end portion 432 in the circumferential direction forms an outer wall 4321 having an outer diameter substantially equal to the first inner diameter Di1. there is The cylindrical portion of the rear end portion 432 has an inner wall 4322 with a second inner diameter Di2 that is less than the first inner diameter Di1. Therefore, the outer wall 4321 of the rear end portion 432 slides against the first inner wall 411 of the housing 410 .

The intermediate portion 436 has the same cylindrical shape as the cylindrical portion of the rear end portion 432 . The intermediate portion 436 has an outer wall 4361 with a first outer diameter Do1 smaller than the first inner diameter Di1 and an inner wall 4362 with an inner diameter equal to the second inner diameter Di2. Therefore, the inner wall 4322 of the rear end portion 432 and the inner wall 4362 of the intermediate portion 436 are continuous with the same second inner diameter Di2. A gap is provided between the outer wall 4361 of the intermediate portion 436 and the inner wall 411 of the housing 410 . A rear end portion of a spring 450, which will be described later, is arranged in this gap.

A columnar space with a second inner diameter Di2 surrounded by the inner wall 4322 of the rear end portion 432 and the inner wall 4362 of the intermediate portion 436 serves as a storage space AS for storing a chemical solution (liquid agent) described later. Therefore, the inner wall 4322 of the rear end portion 432 and the inner wall 4362 of the intermediate portion 436 commonly act as a second inner wall for forming the accommodation space AS.

The front end portion 434 has a cross-shaped outer shape when viewed from the front, and has a cylindrical inner wall 4342 in the central portion. The distance between the outer walls 4341 that are most spaced apart and virtually formed in the circumferential direction of the cross-shaped profile of the front end portion 434 has a second outer diameter Do2 that is smaller than the first outer diameter Do1. Also, the inner wall 4342 of the front end 434 has a third inner diameter Di3 that is smaller than the second inner diameter Di2. The holding member 440 is arranged on the inner wall 4342 of the front end portion 434 . Therefore, the rear end portion 422 of the injection needle (catheter) 420 is held by the front end portion 434 of the first movable body 430 via the holding member 440 . It should be noted here that the cylindrical inner space of the injection needle (catheter) 420 communicates with the housing space AS.

Therefore, the first movable body 430 functions as a first piston that reciprocates in the front-rear direction X along the central axis CA within the first cylinder using the housing 410 as a first cylinder. The first movable body 430 is moved in the forward direction X1 along the central axis CA by a first movable element (first operating portion) of an external actuator, which will be described later. Therefore, the first movable body 430 functions as a first driven body that moves the injection needle (catheter) 420 in the forward direction X1 along the central axis CA.

4 to 6 show the cartridge injector 400 in its initial state. The housing 410 has a rear end portion 413 in the rearward direction X2 (second direction). The rear end 413 has a protrusion 4131 that protrudes radially inward from the inner wall 411 of the housing 410 . Therefore, the inner diameter of the projecting portion 4131 is slightly smaller than the first inner diameter Di1. In the initial state, the rear ends 432b of the four ridges of the rear end portion 432 of the first movable body 430 and the projecting portion 4131 of the rear end portion 413 of the housing 410 are engaged. Here, "engagement" means to engage with each other.

Inside the housing 410, the spring 450 is arranged on the forward direction X1 (first direction) side. The spring 450 is arranged to extend in the front-rear direction X along the central axis CA. The spring 450 has a front end 451 in the forward direction X1 (first direction) and a rear end 452 in the rearward direction X2 (second direction). A front end 451 a of the front end portion 451 of the spring 450 engages a rear end 412 b of the front end portion 412 of the housing 410 . As described above, the rear end portion 452 of the spring 450 is arranged in the gap formed between the outer wall 4361 of the intermediate portion 436 of the first movable body 430 and the inner wall 411 of the housing 410 . A rear end 452 b of the rear end 452 of the spring 450 engages with front ends 432 a of the four ridges of the rear end 432 of the first movable body 430 .

Therefore, the spring 450 is arranged along the central axis CA between the front end portion 412 of the housing 410 and the rear end portion 432 of the first movable body 430 . 4-6 show the initial state of the cartridge injector 400, as previously described. In this initial state, the spring 450 does not apply a biasing force to the first movable body 430 arranged inside the housing 410 . However, when first movable body 430 tries to move in forward direction X1 (first direction) along central axis CA, spring 440 moves first movable body 430 to housing 410 by its urging force. is biased in the rearward direction X2 (second direction) relative to. That is, the spring 450 functions as a biasing means that biases the first movable body 430 toward the housing 410 along the central axis CA in the rearward direction X2 (second direction). Therefore, in the initial state, the spring 450 locks the rear end 432b of the rear end 432 of the first movable body 430 to the protrusion 4131 of the rear end 413 of the housing 410 . Here, "locking" means engaging and stopping.

Therefore, the first movable body 430 and the second movable body 460 described later resist the biasing force of the spring 450 from the initial state by the first movable element (first operating portion) of the external actuator described later. Then, it is moved in the forward direction X1 (first direction) along the central axis CA. When the first driving force (first thrust; first Lorentz force) of the first movable element of the external actuator disappears, the first movable body 430 returns to its initial state by the biasing force of the spring 450. It becomes possible to

In addition, as described above, the cylindrical space surrounded by the second inner wall 4322 of the rear end portion 432 of the first movable body 430 and the second inner wall 4362 of the intermediate portion 436 is filled with the liquid medicine. It is an accommodation space AS for accommodation. A second movable body 460 is arranged on the rearward X2 (second direction) side of the accommodation space AS. The second movable body 460 has a substantially cylindrical outer shape and is movable in the forward direction X1 along the central axis CA. The outer peripheral wall of the second movable body 460 is substantially the same as the second inner diameter Di2 of the second inner wall 4322 of the rear end portion 432 of the first movable body 430 and the second inner wall 4362 of the intermediate portion 436. have an outer diameter. That is, the outer peripheral wall of the second movable body 460 can slide with respect to the second inner walls (4322; 4362) of the first movable body 430. As shown in FIG.

The second movable body 460 consists of a front member 462 provided in the front direction X1 (first direction) and a rear member 464 provided in the rear direction X2 (second direction). The front member 462 and rear member 464 are interlocked together like a lock and key. The front member 462 has a role as a gasket (packing). The front member 462 has a circular front wall surface 462a in its front direction X1 (first direction). The rear member 464 has an annular rear wall surface 464b in the rear direction X2 (second direction). Therefore, more precisely, the accommodation space AS includes the second inner wall 4322 of the rear end portion 432 of the first movable body 430, the second inner wall 4362 of the intermediate portion 436, and the annular shape of the front end portion 434. It is a cylindrical space surrounded by the rear wall surface 434 b and the front wall surface 462 a of the second movable body 460 . The housing space AS contracts as the second movable body 460 moves in the forward direction X1 (first direction) relative to the first movable body 430 . Due to the contraction of the storage space AS, the drug solution (liquid drug) stored in the storage space AS is discharged to the outside through the internal space of the injection needle (catheter) 420 .

Therefore, the second movable body 460 works as a second piston capable of reciprocating in the front-rear direction X along the central axis CA within the second cylinder using the first movable body 430 as a second cylinder. . The second movable body 460 is moved in the forward direction X1 (first direction) along the central axis CA by a second movable element (second operating portion) of an external actuator, which will be described later. Therefore, the second movable body 460 functions as a second driven body for pushing out the liquid medicine (liquid agent) in the housing space AS in the forward direction X1 (first direction) along the central axis CA.

The cartridge injector 400 having such a configuration is operated as follows. First, as described above, the combination of the first movable body 430 and the second movable body 460 is moved from the initial state by the spring 450 by the first movable element (first operating portion) of the external actuator. It is moved in the forward direction X1 (first direction) along the central axis CA against the force. As a result, the injection needle (catheter) 420 protrudes from the opening 4121 of the housing 410 in the forward direction X1 (first direction) along the central axis CA, and the tip 421 of the injection needle (catheter) 420 is positioned at the upper left of the person 200. The muscles are reached from the arm 210 (see FIGS. 1-3). After that, the second movable body 460 moves the chemical solution (liquid agent) in the accommodation space AS forward in the X1 (first direction). As a result, the drug solution (liquid drug) stored in the storage space AS is pushed out into the muscles of the person 200 through the internal space of the injection needle (catheter) 420 . After that, the driving force (thrust; Lorentz force) of the first mover and the second mover of the external actuator disappears. As a result, the projecting injection needle (catheter) 420 is automatically retracted inside the housing 410 by the biasing force of the spring 450 .

The first movable body 430 is also called an outer cylinder, and the second movable body 460 is also called an inner cylinder.

7 to 9, the configuration of linear motor 500 used as an external actuator for driving cartridge injector 400 shown in FIGS. 4 to 6 will be described. FIG. 7 is a perspective cross-sectional view of the linear motor 500 and the cartridge injector 400 arranged in the operation portion of the second housing 132 as seen obliquely from the front right. FIG. 8 is a schematic right side cross-sectional view of the linear motor 500 together with the cartridge injector 400 arranged in the operation portion of the second housing 132, viewed from the approximately right side. FIG. 9 is a perspective cross-sectional view of the linear motor 500 and the cartridge injector 400 arranged in the operation portion of the second housing 132 as seen obliquely from the rear right.

7 to 9 also use the same orthogonal coordinate system (X, Y, Z) as shown in FIGS. 1 to 3, as described above. Since the orthogonal coordinate system (X, Y, Z) used has already been described in detail, its description is omitted for the sake of simplicity.

Before describing the configuration of linear motor 500, the configuration of injector module 130 around linear motor 500 (that is, peripheral components of linear motor 500) will be described.

As described with reference to FIGS. 1 to 3, the injector module 130 includes a first housing 131 that covers the linear motor 500, which is an external actuator, and a second housing 132 that covers the plurality of cartridge injectors 400. including. The injector module 130 includes a base 133 extending in the front-rear direction X parallel to the central axis CA inside the first housing 131 and the second housing 132 . The base 133 has a front end 133 a within the second housing 132 and a rear end 133 b within the first housing 131 . Inside the second housing 132, on the front direction X1 (first direction) side of the base 133, a holding block 134 for holding the cartridge injector 400 in operation is erected upward from the base 133 in the Z1 direction. there is Therefore, this holding block 134 constitutes the operating portion of the second housing 132 .

In the first housing 131, first and second brackets 136, 137 and another bracket 138 stand upright from the base 133 in the upward direction Z1. Another bracket 138 is provided adjacent to the holding block 134 and separated by a predetermined distance L1. The first bracket 136 is erected substantially from the center of the base 133 . The second bracket 137 is erected on the rearward X2 (second direction) side of the base 133 . The first and second brackets 136 and 137 are for holding the stator of the linear motor 500 which will be described later.

A guide rail 150 is laid on the base 133 along the central axis CA. The guide rail 150 has a front end 150a in the forward direction X1 (first direction) and a rear end 150b in the rearward direction X2 (second direction). A front end 150 a of the guide rail 150 is between another bracket 138 and the first bracket 136 . The rear end 150b of the guide rail 150 is between the second bracket 137 and the rear end 133b of the base 133 and is close to the rear end 133b of the base 133. As shown in FIG. First and second sliding members 151 and 152 slidable in the front-rear direction X parallel to the central axis CA are erected on the guide rail 150 . The first sliding member 151 is configured to be slidable in the front-rear direction X parallel to the central axis CA on the guide rail 150 between another bracket 138 and the first bracket 136 . The second sliding member 152 extends between the second bracket 137 and the rear end 133b of the base 133 (the rear end 150b of the guide rail 150) on the guide rail 150 in the front-rear direction X parallel to the central axis CA. It is configured to be slidable.

The first and second sliding members 151 and 152 are for holding a first mover of the linear motor 500, which will be described later. Therefore, the first mover of the linear motor 500 is movable in the longitudinal direction X along the central axis CA above the guide rail 150 together with the first and second sliding members 151 and 152 .

Next, the configuration of the linear motor 500 for driving the cartridge injector 400 held by the holding block 134 will be described with reference to FIGS. 7 to 9. FIG. First, main body parts of linear motor 500 will be described, and then accessory parts of linear motor 500 will be described.

As is clear from FIGS. 7 to 9, like the cartridge injector 400, the body part of the linear motor 500 also has a shape substantially rotationally symmetrical with respect to the central axis CA extending in the front-rear direction X. . Therefore, the cartridge injector 400 held by the holding block 134 and the body part of the linear motor 500 share the same central axis CA.

Linear motor 500 includes a stator 510 and a mover as its main body parts. The mover is arranged to be movable in the longitudinal direction X along the central axis CA with respect to the stator 510 . The mover consists of a first mover 520 and a second mover 530 . The first mover 520 is arranged to be movable in the front-rear direction X along the central axis CA with respect to the stator 510 . The second mover 530 is arranged to be movable in the front-rear direction X along the central axis CA with respect to the first mover 520 . In this way, since the linear motor 500 is provided with the two movers 520 and 530 as movers, the two different driven bodies 430 and 460 of the cartridge injector 400 can be moved in a two-stage extension operation. It is possible. Below, the mover formed by combining the first mover 520 and the second mover 530 is referred to as mover (520; 530).

In the illustrated example, the second mover 530 has a substantially cylindrical shape arranged on and near the central axis CA. The first mover 520 is arranged near the outer periphery of the second mover 530 and has a substantially cylindrical shape. The stator 510 is arranged in the vicinity of the outer periphery of the first mover 520 and has a substantially cylindrical shape.

Specifically, the first mover 520 includes a plurality of cylindrical permanent magnets 522 having an annular cross-sectional shape and arranged along the central axis CA. In the illustrated example, the first mover 520 includes four permanent magnets 522 . The plurality of permanent magnets 522, as shown in FIG. 10, generate outer magnetic flux OM and inner magnetic flux IM to their outer and inner circumferences, respectively.

The stator 510 has a plurality of outer electromagnet coils 512 continuously arranged along the central axis CA so as to surround the first mover 520 via an outer gap with respect to the first mover 520 . include. In the illustrated example, stator 510 includes fifteen outer electromagnet coils 512 . The stator 510 can cause the first mover 520 to travel along the central axis CA due to the interaction between the outer current flowing through the plurality of outer electromagnet coils 512 and the outer magnetic flux OM. At this time, the second mover 530 is also caused to travel along the central axis CA together with the first mover 520 . Therefore, the stator 510 allows the mover (520; 530) to run along the central axis CA due to the interaction between the outer current and the outer magnetic flux OM.

The second mover 530 has a plurality of inner electromagnets arranged continuously along the central axis CA so as to be surrounded by the first mover 520 via an inner gap with respect to the first mover 520. includes a coil 532 for In the illustrated example, the second armature 530 includes twelve inner electromagnet coils 532 . The second mover 530 can travel along the central axis CA with respect to the first mover 520 due to the interaction between the inner current flowing through the plurality of inner electromagnet coils 532 and the inner magnetic flux IM.

Stator 510 includes an outer U-phase coil, an outer V-phase coil, and an outer W-phase coil that are star-connected as a plurality of outer electromagnet coils 512 . Similarly, the second mover 530 includes an inner U-phase coil, an inner V-phase coil, and an inner W-phase coil that are star-connected as the plurality of inner electromagnet coils 532 . Therefore, the linear motor 500 is a three-phase linear motor.

A U-phase coil, a V-phase coil, and a W-phase coil that are used as the plurality of outer electromagnet coils 512 or the plurality of inner electromagnet coils 532 will be described with reference to FIG. 11 .

FIG. 11 shows an example of connections in the case where three sets of three U-phase coils, W-phase coils, and V-phase coils constitute one set of basic configuration, that is, nine coils in total, and a connection example in which the control driver 600 is used. indicates When the control driver 600 is connected to a single-phase 100V AC power supply 700, it incorporates a single-phase-to-three-phase converter. connected to the coil. However, the U-phase, V-phase, and W-phase of the power supply are not necessarily connected to the U-phase coil, the V-phase coil, and the W-phase coil in a one-to-one relationship. There are various forms of connection between the power source and the U-phase coil, the V-phase coil, and the W-phase coil.

The control driver 600 is also connected to the computer such as a personal computer as control data input means and data processing means. The control driver 600 controls the operation of the first mover 520 or the second mover 530 based on operation instructions given from the computer.

Here, for the U-phase coil, the winding start S of the first coil U1 is connected to the U terminal of the control driver 600, and the winding end E of the first coil U1 is connected to the winding end E of the second coil U2. connected to. The winding start end S of the second coil U2 is connected to the winding start end S of the third coil U3, and the winding end E of the third coil U3 is connected to the common terminal. Similarly, for the W-phase coil, the winding end E of the first coil W1 is connected to the W terminal of the control driver 600, and the winding start S of the first coil W1 is connected to the winding start S of the second coil W2. connected to. The winding end E of the second coil W2 is connected to the winding end E of the third coil W3, and the winding start S of the third coil W3 is connected to the common terminal. On the other hand, for the V-phase coil, the winding start S of the first coil V1 is connected to the V terminal of the control driver 600, and the winding end E of the first coil V1 is connected to the winding end E of the second coil V2. Connected. The winding start end S of the second coil V2 is connected to the winding start end S of the third coil V3, and the winding end E of the third coil V3 is connected to the common terminal.

Simply put, when nine coils are provided as shown in FIG. The connections are reversed, and for the remaining one phase, the coils on both sides of the three coils are connected to the coil between them with the winding start end S and the winding end end E reversed.

In the case of having 12 or more, that is, 4 or more sets of coils, the plurality of U-phase coils, the plurality of W-phase coils, and the plurality of V-phase coils in the plurality of sets are connected in series for each phase. and connected to the control driver 600 by star connection. Moreover, the plurality of coils in two phases are connected so that the magnetic poles in the even numbered set are opposite to the magnetic poles in the odd numbered set, and the plurality of coils in the remaining one phase are connected so that the magnetic poles in the odd numbered set are opposite to the magnetic poles in the two phases. , and the magnetic poles in the even set of the plurality of coils are connected in opposite directions to the magnetic poles in the even set of the plurality of coils in the two phases.

Each of the plurality of permanent magnets 522 has a length dimension three times that of each phase coil. As shown in FIG. 10, the plurality of permanent magnets 522 are combined in series along the central axis CA such that adjacent magnetic poles of the same pole are in close contact with each other. However, a ring-shaped spacer made of a magnetic material such as an iron plate may be interposed between the permanent magnets 522 having the same magnetic poles.

In the stator 510, a plurality of outer electromagnet coils 512 are accommodated in a tubular body 514 having grooves. Cylindrical body 514 is fixed between first bracket 136 and second bracket 137 .

Each of first bracket 136 and second bracket 138 has a circular opening through which first armature 520 can pass. Therefore, the first mover 520 extends in the front-rear direction X along the central axis CA through the openings of the first bracket 136 and the second bracket 137 . In the first mover 520 , multiple permanent magnets 522 are housed in a cylindrical case 524 . The case 524 extends in the front-rear direction X along the central axis CA through openings in the first bracket 136 and the second bracket 137 . The case 524 has a front end portion 5241 in the forward direction X1 (first direction) and a rear end portion 5242 in the rearward direction X2 (second direction). A front end portion 5241 of the case 524 is held by the first sliding member 151 . A rear end portion 5242 of the case 524 is held by the second sliding member 152 . With such a configuration, the first mover 520 can move in the front-rear direction X along the central axis CA above the guide rail 150 together with the first and second sliding members 151 and 152 .

The second mover 530 includes a center core 534 arranged to be movable in the front-rear direction X along the central axis CA with respect to the first mover 520 . Center core 534 has a substantially cylindrical shape. A plurality of inner electromagnet coils 532 are mounted around the center core 534 . More specifically, the center core 534 includes a front core portion 5341 on the front direction X1 (first direction) side, a rear core portion 5342 on the rear direction X2 (second direction) side, and a center core portion 5342 therebetween. and a central core portion 5343 . A first O-ring 536 is fitted to the center core 534 at a location between the front core portion 5341 and the central core portion 5343 . A second O-ring 537 is fitted to the center core 534 between the central core portion 5343 and the rear core portion 5342 . A plurality of inner electromagnet coils 532 are mounted around the center core 534 between the first O-ring 536 and the second O-ring 537 .

Next, accessories of the linear motor 500 will be described. The linear motor 500 includes a cylindrical first operating portion 560, a columnar second operating portion 570, and a stopper 580 as accessory parts.

The first operating portion 560 is provided on the front surface 151a of the first sliding member 151 so as to extend in the forward direction X1 (first direction) along the central axis CA. The first operating portion 560 includes a cylindrical tubular portion 562 and a cylindrical body 564 .

In the first operating portion 560 , the tubular portion 562 has a cylindrical portion 5622 , an annular bottom portion 5624 and a grip portion 5626 . Cylindrical portion 5622 extends in forward direction X1 (first direction) along central axis CA. An annular bottom 5624 extends radially outwardly from the rear end of cylindrical portion 5622 . This annular bottom portion 5624 is fixed to the front surface 151 a of the first sliding member 151 . A gripping portion 5626 is integrally attached to the front end of the cylindrical portion 5622 and grips the rear end portion of the cylindrical body 564 .

The cylindrical body 564 gripped by the gripping portion 5626 of the tubular portion 562 has a cylindrical shape extending in the forward direction X1 (first direction) from the tubular portion 562 along the central axis CA. This cylindrical body 564 has an outer diameter smaller than the diameter of the opening 1381 in another bracket 138 . Therefore, the cylindrical body 564 is movable in the forward direction X1 (first direction) along the central axis CA through the opening 1381 of another bracket 138 .

When the cylindrical body 564 moves in the forward direction X1 (first direction), the front end (tip) 564a of the cylindrical body 564 is the rear end of the first movable body 430 of the cartridge injector 400 held by the holding block 134. 432 abuts on the rear end 432b (see FIG. 5). Here, "abutting" means contacting in abutted state. Then, the cylindrical body 564 moves the combination of the first movable body 430 and the second movable body 460 in the forward direction X1 (first direction) along the central axis CA while being in contact with each other. The cylindrical body 564 has an inner diameter slightly larger than the first inner diameter Di2 of the first movable body 430 . Therefore, the front end (tip) 564a of the cylindrical body 564 does not come into contact with the rear wall surface 464b (see FIG. 6) of the second movable body 460 of the cartridge injector 400. FIG.

A first spring 566 is arranged on the outer periphery of the first operating portion 560 . A first spring 566 is positioned between an annular bottom 5624 of tubular portion 562 and a cylindrical recess 1382 of another bracket 138 . That is, the first spring 566 is arranged between the first sliding member 151 and another bracket 138 . The front end 566 a of the first spring 566 contacts the cylindrical recess 1382 of another bracket 138 and the rear end 566 b of the first spring 566 contacts the annular bottom 5624 of the tubular portion 562 .

7 to 9 illustrate the case where the linear motor 500 is in the initial state. In this initial state, the first spring 566 is in a state in which it does not substantially exert its first biasing force. In this initial state, it is assumed that an outer current is caused to flow through the plurality of outer electromagnet coils 512 of the stator 510 . In this case, due to the interaction between the outer current and the outer magnetic flux OM of the first armature 520, the armature (520; 530) moves along the central axis CA along with the first and second sliding members 151 and 152. to move in the forward direction X1 (first direction). Therefore, the first operating portion 560 (cylindrical portion 562 and cylindrical body 564 ) fixed to the first sliding member 151 resists the first biasing force of the first spring 566 and moves toward the center axis. Move in the forward direction X1 (first direction) along CA.

When the supply of the outer current to the plurality of outer electromagnet coils 512 of the stator 510 is stopped, the first thrust (first driving force; first Lorentz force) on the mover (520; 530) disappears. Therefore, by the first biasing force of the first spring 566, the mover (520; 530), the first and second sliding members 151 and 152, the first operating portion 560 (cylindrical portion 562 and cylindrical body). 564) automatically returns to the initial state illustrated in FIGS. Therefore, the first spring 566 acts as a first biasing means that biases the mover (520; 530) in the rearward direction X2 (second direction).

The second operating portion 570 has a substantially cylindrical shape that extends along the central axis CA from the front surface 534a of the center core 534 of the second mover 530 so as to protrude in the forward direction X1 (first direction). consists of a bar of A rear end portion of the second operating portion 570 is fitted into a recess formed in the front core portion 5341 of the center core 534 . The second operating portion 570 passes through the cylindrical portion 562 and the cylindrical body 564 of the first operating portion 560 without contact (with a gap). The second operating portion 570 has a projecting portion 570a at its tip in the forward direction X1 (first direction).

As described above, FIGS. 7 to 9 illustrate the case where the linear motor 500 is in its initial state. In this initial state, the projecting portion 570a of the second operating portion 570 is substantially at the same position in the front-rear direction X as the front end (tip) 564a of the cylindrical body 564 of the first operating portion 560. As shown in FIG. In this initial state, when the second operating portion 570 moves in the forward direction X1 (first direction), the protruding portion 570a of the second operating portion 570 moves toward the second position of the cartridge injector 400 held by the holding block 134. abuts on the rear wall surface 464b (see FIG. 6) of the movable body 460 of. Then, the second operating portion 570 moves the second movable body 460 in the forward direction X1 (first direction) along the central axis CA while being in contact with it. The second operating portion 570 has a diameter slightly smaller than the second inner diameter Di2 of the first movable body 430 . Therefore, the projecting portion 570a of the second operating portion 570 does not come into contact with the rear end 432b (see FIG. 5) of the rear end portion 432 of the first movable body 430 of the cartridge injector 400. FIG.

The stopper 580 is fixed to the second sliding member 152 while being fitted in the circular opening of the second sliding member 152 . The stopper 580 has a cylindrical shape extending from the second sliding member 152 in the forward direction X1 (first direction) along the central axis CA. A rear core portion 5342 of the center core 534 of the second mover 530 penetrates the inside of the stopper 580 with a gap. A second O-ring 537 attached to the center core 534 is engaged with the annular front surface 580a of the stopper 580 in the forward direction X1 (first direction).

In the circular opening of the first sliding member 151, the cylindrical holding portion 153 extends in the rearward direction X2 (second direction) along the central axis CA while being inserted into the inner peripheral wall of the front end portion 5241 of the case 524. ). The inner diameter of the holding portion 153 is larger than the outer diameter of the center core 534 . Therefore, the front core portion 5341 of the center core 534 passes through the holding portion 153 with a gap. A first cap portion 156 having the same inner diameter as the inner diameter of the holding portion 153 is fixed to the rear surface 153b of the holding portion 153 so as to protrude in the rearward direction X2 (second direction). Therefore, the front core portion 5341 of the center core 534 also passes through this first cap portion 156 with a gap. On the other hand, a hollow second cap portion 157 is attached to the first O-ring 536 attached to the center core 534 so as to protrude in the forward direction X1 (first direction). The inner diameter of the second cap portion 157 may be substantially the same as or slightly larger than the outer diameter of the center core 534 . Because the second cap portion 157 is attached to the first O-ring 536, when the center core 534 moves in the longitudinal direction X along the axial direction CA, the second cap portion 157 and the center core 534 move. because they move together.

A second spring 572 is arranged on the outer periphery of the front core portion 5341 of the center core 534 . A second spring 572 is positioned between the first cap portion 156 and the second cap portion 157 . That is, the second spring 572 is arranged in a space formed in the rearward direction X2 (second direction) of the first sliding member 151 and on the inner peripheral side of the first mover 520. It is The front end 572 a of the second spring 572 contacts the bottom of the first cap portion 156 and the rear end 572 b of the second spring 572 contacts the bottom of the second cap portion 157 .

7 to 9 illustrate the case where the linear motor 500 is in the initial state. In this initial state, the second spring 572 is in a state where it does not substantially exert its biasing force. In this initial state, it is assumed that an inner current is caused to flow through the plurality of inner electromagnet coils 532 of the second mover 530 . In this case, due to the interaction between the inner current and the inner magnetic flux IM of the first mover 520, the second mover 530 moves toward the first mover 520 in the forward direction X1 along the central axis CA. Attempt to move in (first direction). Therefore, the second operating portion 570 fixed to the second mover 530 moves forward in the X1 (first direction) along the central axis CA against the biasing force of the second spring 572. Moving.

When the supply of the inner current to the plurality of inner electromagnet coils 532 of the second mover 530 is stopped, the second thrust (second driving force; second Lorentz force) on the second mover 530 disappears. do. Therefore, the second urging force of the second spring 572 automatically restores the second mover 530 and the second operating portion 570 to the initial states shown in FIGS. Therefore, the second spring 572 acts as a second biasing means that biases the second mover 530 in the rearward direction X2 (second direction).

Next, the overall operation of the injector module 130 (cartridge injector 400 and linear motor 500) will be described with reference to FIGS. 4 to 9. FIG.

In the initial state shown in FIGS. 7 to 9, an outer current is passed through the plurality of outer electromagnet coils 512 of the stator 510 of the linear motor 500 under the control of the controller. As a result, the interaction between this outer current and the outer magnetic flux OM (see FIG. 10 ) generated from the plurality of permanent magnets 522 of the first mover 520 causes a first A first thrust (first Lorentz force) acts on one mover 520 to move in the forward direction X1 (first direction) along the central axis CA. Therefore, by this first thrust (first Lorentz force), the mover (520; 530) moves against the first biasing force of the first spring 566 on the guide rail 150 in the first and second positions. Together with the second sliding members 151 and 152, it moves (runs) in the forward direction X1 (first direction).

Along with the movement (running) of the mover (520; 530) in the forward direction X1 (first direction), the first operating portion 560 fixed to the first sliding member 151 also moves along the central axis CA. to move in the forward direction X1 (first direction). When the first operating portion 560 moves in the forward direction X<b>1 (first direction) along the central axis CA, the front end (tip) 564 a of the first operating portion 560 moves toward the first movable position of the cartridge injector 400 . While engaging with the rear end 432b of the body 430, the first movable body 430 is moved in the forward direction X1 (first direction) along the central axis CA against the biasing force of the spring 450.

As a result, the injection needle (catheter) 420 protrudes from the distal end portion 412 of the housing 410 of the cartridge injector 400 through its opening 4121, and the distal end 421 of the projected injection needle (catheter) 420 is attached to the left upper arm 310 of the person 200. to reach the person's 200 muscles. This completes the needle projection step.

Subsequently, under the control of the controller, an inner current is passed through the plurality of inner electromagnet coils 532 of the second mover 530 of the linear motor 500 . As a result, the interaction between this inner current and the inner magnetic flux IM (see FIG. 10) generated from the plurality of permanent magnets 522 of the first mover 520 causes relative Specifically, a second thrust (second Lorentz force) acts on the second mover 530 to move it in the forward direction X1 (first direction) along the central axis CA. Therefore, by this second thrust (second Lorentz force), the second mover 530 moves forward in the X1 (first direction) against the second biasing force of the second spring 572. Move (run).

Along with the movement (running) of the second mover 530 in the forward direction X1 (first direction), the second operation part 570 fixed to the tip of the second mover 530 also moves along the central axis CA. move in the forward direction X1 (first direction). When the second operating portion 570 moves in the forward direction X1 (first direction) along the central axis CA, the projecting portion 570 a at the tip of the second operating portion 570 moves toward the second position of the cartridge injector 400 . While engaging with the rear wall surface 464b of the movable body 460, the second movable body 460 is moved in the forward direction X1 (first direction) along the central axis CA.

As a result, the accommodation space AS of the first movable body 430 of the cartridge injector 400 is contracted, and the drug solution (liquid drug) accommodated in the accommodation space AS passes through the inner space of the injection needle (catheter) 420. , is extruded from its tip 421 into the muscle of the person 200 . This completes the liquid chemical extrusion step.

After the intramuscular injection is finished in this manner, the outer current and the inner current are stopped under the control of the controller. As a result, both the above-described first and second thrusts (first and second Lorentz forces) disappear. As a result, the first biasing force of the first spring 566 of the linear motor 500 biases the mover (520; 530) in the rearward direction X2 (second direction) along the central axis CA, The second biasing force of the second spring 572 also biases the second mover 530 in the rearward direction X2 (second direction) along the central axis CA. As a result, the first mover 520, the first and second sliding members 151 and 152, the first operating portion 560, the second mover 530, and the second operating portion 570 all move backward. It automatically retracts to X2 (second direction). This retraction returns the linear motor 500 to the initial state illustrated in FIGS.

Simultaneously with the retraction, the biasing force of the spring 450 of the cartridge injector 400 also biases the first movable body 430 in the housing 410 in the rearward direction X2 (second direction) along the central axis CA. As a result, injection needle (catheter) 420 protruding outside is retracted into housing 410 . This completes the needle withdrawal step.

As is clear from the above description, according to the embodiment of the present invention, the linear motor 500 performs a two-step extension operation that moves two different driven bodies (430, 460) of the cartridge injector 400. Is possible.

Although the present invention has been described with reference to the embodiments, the present invention is not limited to the above-described embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

For example, in the linear motor 500 according to the above-described embodiment, the first and second springs 566 and 572 are used as the first and second urging means. Of course, other types of biasing means may be used, such as comprising: Further, in the above-described embodiment, the initial position of the linear motor 500 is defined using the stopper 580 . However, instead of using the stopper 580, a position detection mechanism such as an encoder may be provided to define the position of the linear motor 500 in its initial state.

The linear motor according to the present invention is not limited to an external actuator for an injector module, but is effective as a linear motor that moves two different driven bodies and performs a two-step extension operation.

100 automated vaccination robotic device 110 base 121 first arm 122 second arm 123 third arm 124 fourth arm 130 injector module (injection device)
131 first housing 132 second housing 133 base 133a front end 133b rear end 134 holding block 136 first bracket 137 second bracket 138 another bracket 1381 opening 1382 cylindrical recess 141 first joint 142 second 2 joint portion 143 third joint portion 144 fourth joint portion 150 guide rail 150a front end 150b rear end 151 first sliding member 151a front surface 152 second sliding member 153 holding portion 153b rear surface 156 first cap Part 157 Second Cap Part 200 Person 210 Left Upper Arm 300 Chair 400 Cartridge Injector
410 housing 411 first inner wall 412 distal end 412b rear end 4121 opening 413 rear end 4131 protrusion 420 injection needle (catheter)
421 tip 422 rear end portion 430 first movable body (first driven body)
432 Rear end 432a Front end 432b Rear end 4321 Outer wall 4322 Second inner wall 434 Front end 434b Rear wall 4341 Outer wall 4342 Inner wall 436 Intermediate part 4361 Outer wall 4362 Second inner wall 440 Holding member 450 Spring 451 Front end 451a Front end 452 rear end 452b rear end 460 second movable body (second driven body)
462 front member (gasket; packing)
462a front wall surface 464 rear member 464b rear wall surface 500 linear motor (external actuator)
510 stator 512 outer electromagnet coil 514 cylindrical body 520 first mover 522 permanent magnet 524 case 5241 front end 5242 rear end 530 second mover 532 inner electromagnet coil 534 center core 534a front surface 5341 front core portion 5342 Rear core portion 5343 Central core portion 536 First O-ring 537 Second O-ring 560 First operating portion 562 Cylindrical portion 5622 Cylindrical portion 5624 Annular bottom portion 5626 Grip portion 564 Cylindrical body 564a Front end (tip)
566 First spring 566a Front end 566b Rear end 570 Second operation part 570a Protruding part 572 Second spring 572a Front end 572b Rear end 580 Stopper 580a Annular front face 600 Control driver 700 AC power supply Da Diameter Di1 First inner diameter Di2 Second second inner diameter Di3 third inner diameter Do1 first outer diameter Do2 second outer diameter CA central axis AS housing space OM outer magnetic flux IM inner magnetic flux

Claims (10)

In a linear motor that includes a stator and a mover that is movably arranged along a central axis with respect to the stator, the mover:
a first mover;
a second mover disposed movably along the central axis with respect to the first mover;
A linear motor consisting of: 2. The linear motor according to claim 1, wherein each of said stator, said first mover, and said second mover has a shape substantially rotationally symmetrical with respect to said central axis. the second mover has a substantially cylindrical shape arranged on and near the central axis,
the first mover has a substantially cylindrical shape arranged near the outer periphery of the second mover,
The stator has a substantially cylindrical shape arranged near the outer periphery of the first mover,
A linear motor according to claim 2. The first mover has an annular cross-sectional shape and includes a plurality of permanent magnets arranged along the central axis. and inner magnetic flux,
The stator includes a plurality of outer electromagnet coils arranged continuously along the central axis so as to surround the first mover via an outer gap with respect to the first mover. an interaction between the outer current flowing through the plurality of outer electromagnet coils and the outer magnetic flux allows the stator to cause the mover to travel along the central axis;
The second mover has a plurality of inner electromagnets arranged continuously along the central axis so as to be surrounded by the first mover via an inner gap with respect to the first mover. The second mover moves along the central axis with respect to the first mover due to the interaction between the inner current flowing through the plurality of inner electromagnet coils and the inner magnetic flux. is drivable,
A linear motor according to claim 3. The stator includes an outer U-phase coil, an outer V-phase coil, and an outer W-phase coil that are star-connected as the plurality of outer electromagnet coils,
The second mover includes an inner U-phase coil, an inner V-phase coil, and an inner W-phase coil that are star-connected as the plurality of inner electromagnet coils,
the linear motor comprises a three-phase linear motor,
A linear motor according to claim 4. each of the plurality of permanent magnets has a length dimension three times the length of each phase coil;
The plurality of permanent magnets are combined in series along the central axis such that adjacent magnetic poles of the same polarity are in close contact with each other.
A linear motor according to claim 5. The mover is configured to move in a first direction along the central axis with respect to the stator when the outer current is applied to the plurality of outer electromagnet coils of the stator. cage,
The second mover moves the first mover along the central axis with respect to the first mover when the inner current flows through the plurality of inner electromagnet coils of the second mover. is configured to move in the direction of
The linear motor is
first biasing means for biasing the mover in a second direction opposite to the first direction when the flow of the outer current is stopped;
a second biasing means for biasing the second mover in the second direction when the flow of the inner current is stopped;
The linear motor according to any one of claims 4 to 6, further comprising: a base arranged parallel to the central axis;
a guide rail attached on the base in parallel with the central axis;
first and second brackets erected from the base and holding the stator at the ends in the first direction and the ends in the second direction, respectively;
It is slidably provided on the guide rail and holds the first mover at both ends thereof at positions separated from the first and second brackets in the first direction and the second direction, respectively. first and second sliding members for
8. The linear motor of claim 7, further comprising: another bracket having an opening erected on the base on the first direction side of the first bracket;
a hollow first operating portion extending from the first sliding member in the first direction along the central axis and capable of passing through an opening of the another bracket;
A second movable element extending in the first direction along the central axis from the end of the second mover in the first direction and inserted into the first operating portion with a space therebetween. an operation unit of
9. The linear motor of claim 8, further comprising: The first biasing means is arranged between the first sliding member and the another bracket,
The second biasing means is arranged in a space formed on the inner peripheral side of the first mover and on the second direction side of the first sliding member. ,
A linear motor according to claim 9 .

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