JP2015066070A - Drug injector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a feed screw-type drug injector that comprises a handle excellent in operability.SOLUTION: A handle 14 of a drug injector 10 includes: a handle body 39; a plurality of first ribs 40 that are elongated in an axial direction on at least a tip end-side outer peripheral surface of the handle body 39 and arranged at intervals in a circumferential direction; and a plurality of second ribs 41 that are elongated in the axial direction on only a base end-side outer peripheral surface of the handle body 39 and arranged at circumferential intervals shorter than the circumferential intervals of the plurality of the first ribs 40.

Description

  The present invention relates to a drug injection tool used for discharging a drug when the drug is injected into an injection space.

  In recent years, percutaneous vertebroplasty (PVP) in which a filler that hardens with time is injected through a bone biopsy needle inserted into a fractured vertebral body for a vertebral body compression fracture caused by osteoporosis or cancer. As the filler, for example, calcium phosphate bone cement or polymethylmethacrylate bone cement (hereinafter, also simply referred to as “bone cement”) having X-ray contrast properties is used. Normally, bone cement has a very high viscosity, and the pressure loss due to the sponge is very large in the vertebra filled with the bone cement, so it is necessary to inject a small amount at a high pressure of 3 MPa or more at the time of injection. .

  As a type of drug injection tool for performing such injection, there is also a piston type that pushes the pusher linearly to discharge bone cement, but when the drug to be used is high viscosity bone cement The lead screw type is advantageous. That is, in the case of the piston type, it is difficult to operate because a very large pushing operation force is required to discharge high-viscosity bone cement. On the other hand, in the case of the feed screw type, the pusher can be advanced with a relatively small rotational operation force by the action of the screw mechanism. The feed screw type drug injection device is disclosed in, for example, Patent Documents 1 and 2 below.

Japanese Patent No. 4068057 Japanese Patent No. 4704748

  In the case of a feed screw type drug injection device, the pusher is provided with a handle for rotating the pusher, and when the drug injection tool is used, the operator grips the handle by hand and rotates the handle. In this case, when the handle is rotated in a predetermined direction (for example, clockwise) for injecting medicine, the pusher moves forward, so that the medicine filled in the outer cylinder can be discharged.

  By the way, in the use of the medicine injection tool, it is assumed that the handle is rotated in the direction opposite to that during the medicine injection. For example, when it is desired to suddenly stop the injection during the injection by the rotation operation of the pusher, the pressure in the system is released by rotating the handle in the reverse direction, so that the injection sudden stop can be performed. Therefore, it is desired that the handle in the feed screw type drug injection device is easy to operate not only for rotation operation during drug injection but also for rotation operation in the opposite direction.

  The present invention has been made in consideration of such problems, and an object of the present invention is to provide a feed screw type drug injection device having a handle with excellent operability.

  In order to achieve the above object, there is provided a drug injection device for discharging a drug filled inside, a cylindrical body having a drug discharge port at the tip, filled with the drug, and a hollow of the cylindrical body A pusher having a shaft that can be inserted into the part, a handle for rotating the shaft, and the pusher in the axial direction with respect to the tubular body as the pusher rotates relative to the tubular body. And a plurality of first ribs extending in the axial direction and arranged at intervals in the circumferential direction at least on the outer peripheral surface of the handle body at least on the distal end side. And a plurality of second ribs extending in the axial direction only on the base end side outer peripheral surface of the handle body and arranged at a circumferential interval smaller than a circumferential interval of the plurality of first ribs. It is characterized by that.

  According to the above-described drug injection device, the circumferential interval between the plurality of first ribs provided on at least the distal end side of the handle is larger than the circumferential interval between the plurality of second ribs provided on the proximal end side. For this reason, at the time of medicine injection, for example, the thumb of the operator's hand can be put between the first ribs on the distal end side, and the handle can be easily rotated. At the time of sudden injection stop, for example, the middle finger can be hooked on the second rib on the base end side to easily perform the reverse rotation operation of the handle. As described above, according to the drug injection device of the present invention, excellent operability can be obtained both when the drug is injected and when the injection is suddenly stopped.

  In the above-described drug injecting device, a filling member that has a head portion that can be liquid-tightly inserted into the hollow portion of the cylindrical body on the tip side of the pusher, and that can be displaced in the axial direction with respect to the pusher; , May be provided. In the case of the drug injection device having such a configuration, the injection sudden stop (pressure release) can be surely performed without causing the drug back flow by simply rotating the handle in reverse during use. Therefore, the structure in which the first rib and the second rib are provided on the handle in the drug injection device provided with such a filling member can smoothly and easily perform the injection sudden stop without causing the drug backflow. This is particularly useful.

  In the medicine injection tool, the distal end side outer peripheral surface of the handle main body may have a tapered shape in which an outer diameter decreases toward the distal end side. With this configuration, the thumb of the operator's hand can be easily placed on the outer peripheral surface on the distal end side of the handle body, and the operability can be further improved.

  In the above-described drug injection device, the protrusion height of the first main rib from the outer peripheral surface of the distal end side of the handle main body may increase toward the distal end side. With this configuration, the thumb of the operator's hand is easily caught, and the operability can be further improved.

  In the above-described drug injecting device, the first rib extends substantially in the entire axial direction on the outer peripheral surface of the handle body, and the second rib is disposed between each of the adjacent first ribs. Also good. With this configuration, the proximal end portion of the first rib has the same function as the second rib, and the first rib and the second rib can be efficiently arranged on the outer peripheral surface of the handle body. .

  In the above-described drug injecting device, the first rib has a length that is at least one half of the axial length of the handle body, and the second rib has an axial length of 2 of the handle body. It may have a length of less than one part. With this configuration, since the rotational operation force when the middle finger is put on the second rib to reversely rotate the handle does not have to be so large, the second rib is appropriately shortened so that the thumb can be put on the front end side of the handle. This area can be made relatively large. Thereby, at the time of injection | pouring of a chemical | medical agent, it is easy to apply the force for putting a thumb on the comparatively wide range of the front end side of a handle | steering-wheel, and performing rotation operation.

  ADVANTAGE OF THE INVENTION According to this invention, the feed screw type chemical injection device provided with the handle | steering_wheel which is excellent in operativity can be provided.

It is a disassembled perspective view of the chemical injection device concerning one embodiment of the present invention. It is a longitudinal cross-sectional view in the assembly state of the chemical injection tool shown in FIG. It is a side view of the base end part of a shaft. FIG. 4A is a side view of the handle, and FIG. 4B is a longitudinal sectional view of the handle. It is a longitudinal cross-sectional view of the connection part of the state in which the pusher and the handle were connected, and its periphery. It is a longitudinal cross-sectional view of the guide member and its peripheral site | part in the chemical injection tool shown in FIG. It is a figure explaining the positional relationship of the scale part provided in the cylindrical body, and the rib provided in the cover member. FIG. 8A is a first diagram illustrating a method of filling a medicine injection device shown in FIG. 1 with a drug, and FIG. 8B is a second diagram illustrating a method of filling the medicine injection device shown in FIG. FIG. 9A is a first diagram for explaining a method of discharging air from the cylindrical body of the drug injection device shown in FIG. 1, and FIG. 9B is a diagram illustrating discharge of air from the cylindrical body of the drug injection device shown in FIG. It is the 2nd figure explaining the method to do. It is a figure which shows the state which isolate | separated a part of filling member of the chemical injection tool shown in FIG. It is a figure explaining the connection of the chemical injection tool and syringe shown in FIG. It is a 1st figure explaining the operation method of the chemical injection tool shown in FIG. It is a figure which shows the structure of the connector of the base end side of the extension tube shown in FIG. It is a 2nd figure explaining the operation method of the chemical injection tool shown in FIG. It is a 3rd figure explaining the operation method of the chemical injection tool shown in FIG. FIG. 16A is a diagram illustrating an example of how to grip a handle when performing an injection operation, and FIG. 16B is a diagram illustrating an example of how to grip a handle when performing an injection sudden stop operation. It is a side view of the handle concerning a modification.

  Hereinafter, preferred embodiments of the drug injection device according to the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is an exploded perspective view showing a drug injection device 10 according to one embodiment of the present invention. FIG. 2 is a longitudinal sectional view of the pharmaceutical injection device 10 shown in FIG. 1 in an assembled state. The drug injection tool 10 is a medical device used for discharging a drug when a drug (filler, injection material) is injected into a desired injection space. For example, bone cement in percutaneous vertebroplasty. Is used to inject into the bone.

  Examples of the drug filled in the drug injection device 10 include, for example, polymethacrylic resin (PMMA) such as polymethyl methacrylate, calcium phosphate cement such as α-type tricalcium phosphate (TCP), β-type TCP, and hydroxyapatite. (CPC) can be used. Furthermore, granules composed of inorganic materials such as calcium phosphate ceramics, alumina ceramics, zirconia ceramics, and titanium can also be used.

  The medicine injection tool 10 is a cylindrical body 12 filled with a medicine, a pusher 13 inserted into a hollow portion of the tubular body 12, a feed screw structure 15 (see FIG. 2), and a pusher 13 that can be advanced and retracted. And a filling member 16 inserted through the.

  The cylindrical body 12 includes a body portion 18 having a lumen (hollow portion) extending in the axial direction, a distal end tube portion 20 protruding from the distal end portion of the body portion 18 toward the distal end side, and a proximal end portion of the body portion 18. And an annular flange portion 22 projecting outward (radially outward) and extending in the circumferential direction. Inside the cylindrical body 12, a filling chamber for filling a medicine is formed by a space surrounded by the cylindrical body 12 and the filling member 16. A drug discharge port 12 a is provided at the distal end of the cylindrical body 12, and a proximal end opening 12 b is provided at the proximal end of the cylindrical body 12. The body part 18, the distal end pipe part 20, and the flange part 22 are integrally formed.

  The body portion 18 includes a parallel portion 18a having a constant inner diameter and a tapered portion 18b having a diameter reduced from the tip of the parallel portion 18a toward the tip tube portion 20, and is formed in a hollow cylindrical shape as a whole. On the outer peripheral surface of the body portion 18, a scale portion 19 indicating the amount of the medicine is provided. As shown in FIG. 7, the scale portion 19 has a plurality of scale lines 19a and a plurality of scale numbers 19b attached to the scale lines 19a. The plurality of scale lines 19 a extend in the circumferential direction of the outer peripheral surface of the body portion 18, and are provided at intervals from each other in the axial direction of the tubular body 12. The plurality of scale numbers 19b are provided at intervals in the axial direction of the cylindrical body 12. The scale numbers 19b in the illustrated example are arranged vertically with respect to the cylindrical body 12, but may be arranged sideways with respect to the cylindrical body 12.

  As shown in FIG. 1, the distal end tube portion 20 forms a medicine discharge port 12a. A male thread portion 27 is formed on the outer peripheral surface of the distal end tube portion 20. The male thread portion 27 is a screw having a single spiral thread, that is, a single thread. When the medicine is injected by such a tip tube portion 20, the tip tube portion 20 can be connected to an extension tube 100 (see FIG. 12 and the like) described later, and can also be connected to a syringe 87 (see FIG. 11).

  In the present embodiment, the flange portion 22 has a non-circular shape. Specifically, the flange portion 22 includes a pair of straight portions 22a that are parallel to each other and a pair of arc portions 22b that connect both ends of the straight portions 22a. Other than the shape shown in FIG. 1, the non-circular flange portion 22 engages with a cover member 62 to be described later, such as an ellipse, a polygon, or a shape protruding outward in a partial range in the circumferential direction. Any shape that does not idle is acceptable.

  The constituent material of the cylindrical body 12 is not particularly limited. For example, polyolefin such as polypropylene, polyurethane, polyethylene, cyclic polyolefin, polymethylpentene 1, polyester, nylon, polycarbonate, polymethylmethacrylate (PMMA), polyetherimide ( PEI), polyethersulfone, polyetheretherketone (PEEK), fluororesin, polyphenylene sulfide (PPS), polyacetal resin (POM) and other resinous materials, stainless steel and other metallic materials, glass, etc. Good. Moreover, it is preferable that the constituent material of the cylindrical body 12 is substantially transparent in order to ensure internal visibility. Moreover, it is preferable that it has strength, elasticity and chemical resistance that can withstand high pressure.

  The pusher 13 includes a shaft 30 that can be inserted into the hollow portion of the cylindrical body 12, and a hollow handle 14 that is provided at the base end of the shaft 30 and has an outer diameter (outward in the radial direction). The pusher 13 can be displaced in the axial direction relative to the filling member 16 and can be relatively rotated in the circumferential direction.

  The shaft 30 has an insertion hole 30a (see FIG. 2) penetrating linearly in the axial direction. The head portion 31 constituting the distal end portion of the shaft 30 has a tapered shape with a diameter reduced toward the distal end side, and the most advanced surface is an annular distal end surface 31a having a small area. The annular tip surface 31 a is a surface perpendicular to the axis of the shaft 30.

  An external thread portion 34 is formed along the axial direction in a predetermined range in the longitudinal direction on the outer peripheral portion of the shaft 30. The outer diameter of the male screw portion 34 is smaller than the inner diameter of the body portion 18 of the cylindrical body 12. A guide member 36 that can be connected to the cover member 62 is attached to the male screw portion 34. The configuration of the guide member 36 will be described later.

  As shown in FIG. 3, a plurality of engagement ribs 32 extending in the axial direction are provided on the outer peripheral surface of the proximal end side of the shaft 30 (four in the illustrated example at regular intervals) with an interval in the circumferential direction. . An annular groove 33 extending annularly in the circumferential direction is provided on the outer peripheral surface of the shaft 30 on the proximal end side with respect to the engagement rib 32. The shaft 30 is engaged with the handle 14 at the engagement rib 32 and the annular groove 33.

  In FIG. 1, a handle 14 is a portion that a user grips (pinch or grips) with fingers when rotating the pusher 13 with respect to a cylindrical body 12 about an axis, and in this embodiment, a shaft 30. It extends in the proximal direction so as to at least partially cover the filling member 16 protruding from the proximal end. Specifically, the handle 14 includes a hollow connection portion 38 connected to the shaft 30, a handle main body 39 having a diameter increased with respect to the connection portion 38, and a plurality of first portions provided on the outer peripheral surface of the handle main body 39. 1 and second ribs 40 and 41.

  As shown in FIG. 4B, the connecting portion 38 has a hollow shape, and a plurality of engaging grooves 42 extending in the axial direction are spaced apart in the circumferential direction on the inner circumferential surface (in the illustrated example, the spacing is equal. 4) provided. The respective engagement grooves 42 provided in the connecting portion 38 and the respective engagement ribs 32 (see FIG. 3) provided in the shaft 30 are engaged, thereby preventing relative rotation between the shaft 30 and the handle 14. ing.

  One or more engagement grooves are provided in place of the engagement ribs 32 on the outer peripheral surface of the proximal end side of the shaft 30, and one or more engagements are provided in the inner peripheral surface of the connection portion 38 of the handle 14 instead of the engagement grooves 42. A mating rib may be provided to prevent relative rotation by engaging the engaging groove with the engaging rib.

  On the inner peripheral surface of the connection portion 38, an inner engagement protrusion 44 that protrudes inward in the radial direction and extends annularly in the circumferential direction is provided on the proximal end side of the engagement groove 42. When the inward engagement protrusion 44 provided on the connecting portion 38 and the annular groove 33 (see FIG. 3) provided on the shaft 30 are engaged, the handle 14 may come out in the proximal direction of the shaft 30. It is blocked.

  In the present embodiment, the engagement structure between the annular groove 33 and the inward engagement protrusion 44 is provided on the base end side relative to the above-described relative rotation prevention structure by the engagement rib 32 and the engagement groove 42. However, in the modification, the axial positional relationship between the engagement structure and the relative rotation prevention structure may be reversed.

  As shown in FIGS. 4A and 4B, the handle body 39 includes a flange portion 45 that expands radially outward from the outer peripheral surface of the connection portion 38, and extends from the outer end of the flange portion 45 in the proximal direction. Cover portion 46. The cover part 46 has a hollow cylindrical shape. The outer peripheral surface on the front end side of the cover portion 46 has a tapered shape in which the outer diameter decreases toward the front end side.

  The plurality of first ribs 40 extend in the axial direction and are spaced apart in the circumferential direction. In the present embodiment, each first rib 40 extends linearly over substantially the entire axial direction of the outer peripheral surface of the handle body 39, but may extend at least on the outer peripheral surface of the handle body 39. That's fine. The first rib 40 may have a length that is at least half the axial length of the handle body 39. The length L1 of the first rib 40 is set to 20 to 100 mm, for example, and preferably 30 to 50 mm.

  The circumferential interval or number of the first ribs 40 is such that the operator's thumb can be easily placed on the portion between the first ribs 40 adjacent to each other on the outer peripheral surface of the handle body 39, and the thumb can be easily caught on the first rib 40. Set to Therefore, the number of the first ribs 40 is, for example, 4 to 16, and preferably 4 to 8. In the illustrated example, eight first ribs 40 are provided at equal intervals in the circumferential direction.

  The distance from the axial center of the handle 14 to the outer end of the first rib 40 is substantially constant along the axial direction, but as described above, the outer peripheral surface on the front end side of the handle main body 39 (cover portion 46) is the front end. It has a tapered shape whose outer diameter decreases in the direction. For this reason, the protrusion height from the front end side outer peripheral surface of the handle body 39 increases as the first rib 40 moves toward the front end side.

  The second ribs 41 extend in the axial direction only on the base end side outer peripheral surface of the handle main body 39 and are arranged at a circumferential interval smaller than the circumferential interval of the first ribs 40. In the present embodiment, the second ribs 41 are disposed between the first ribs 40 adjacent to each other in the circumferential direction. The number of the second ribs 41 arranged between each of the first ribs 40 is not limited to two as in the illustrated example, and may be one or three or more. The length L2 of the second rib 41 is set, for example, to 5-30 mm, and preferably 10-20 mm.

  The outer diameter D of the handle 14 including the first rib 40 and the second rib 41 is set to an appropriate size so that the operator can easily grip and apply the force to perform the rotation operation. For example, the outer diameter D of the handle 14 is set to 30 to 60 mm, preferably 40 to 50 mm.

  In the handle 14 configured as described above, an operation is performed between the first ribs 40 on the outer peripheral surface of the handle main body 39 and in a region on the tip side of the second rib 41, that is, on the tip side outer peripheral surface. For example, the handle 14 can be rotated by putting a thumb on the person. Further, the handle 14 can be rotated in reverse by placing the middle finger of the operator on the second rib 41 or placing the middle finger on both the proximal end portion of the first rib 40 and the second rib 41.

  The constituent material of the shaft 30 and the handle 14 constituting the pusher 13 can be selected from those exemplified as the constituent material of the cylindrical body 12 described above. In this case, the constituent materials of the shaft 30 and the handle 14 may be the same, but may be made of different materials so as to be suitable for each member. For example, since the shaft 30 is screwed with the guide member 36 by the male screw portion 34, the shaft 30 is made of a material (for example, polyacetal resin) that is slippery (low frictional resistance) in order to reduce rotational resistance with respect to the guide member 36. obtain. On the other hand, the handle 14 is a portion that is strongly gripped by the operator and is subjected to a large load. Therefore, the handle 14 can be made of a highly rigid material (for example, polycarbonate).

  An example of the joining means between the shaft 30 and the handle 14 is an adhesive. However, when the joining means using an adhesive is employed when the shaft 30 and the handle 14 are made of different materials, the adhesiveness is poor and sufficient. There is a risk that a sufficient bonding strength cannot be obtained. The joining means between the shaft 30 and the handle 14 can prevent the handle 14 from coming off from the shaft 30 when the pusher 13 is used and can prevent relative rotation between the shaft 30 and the handle 14 (transmit torque). It is necessary.

  Therefore, in the present embodiment, the relative rotation between the shaft 30 and the handle 14 is prevented by the engagement between the engagement rib 32 and the engagement groove 42 without using an adhesive, and the annular groove 33 and the inward engagement. A structure is employed that prevents the handle 14 from coming off the shaft 30 by engagement with the mating protrusion 44. With this configuration, the shaft 30 and the handle 14 having different constituent materials can be connected with sufficient strength.

  Next, the filling member 16 will be described with reference to FIGS. 1 and 2. The filling member 16 is a device for sucking the drug into the cylindrical body 12 by being moved in the proximal direction when the drug is filled into the cylindrical body 12 through the drug discharge port 12a. The pusher 13 is disposed so as to be displaceable in the axial direction. The filling member 16 is provided on the pusher 13 so as to be inserted in a liquid-tight manner into the hollow portion of the cylindrical body 12 on the distal end side with respect to the pusher 13, and to extend in the proximal direction from the head portion 50. The shaft portion 52 is inserted through the insertion hole 30a, and the grip portion 54 is provided at the base end of the shaft portion 52.

  The head portion 50 is a portion that constitutes the tip portion of the filling member 16, and is within the range restricted by the tapered portion 18 b of the cylindrical body 12 and the head portion 31 of the pusher 13 in the cylindrical body 12. It can move in the axial direction. A seal member 56 (for example, a silicone O-ring or the like) is attached to the head unit 50. In the illustrated example, an annular seal groove 57 (see FIG. 2) extending in the circumferential direction is formed on the outer periphery of the head portion 50, and a ring-shaped seal member 56 is disposed in the seal groove 57. Since such a seal member 56 slides in the axial direction while being in close contact with the inner peripheral surface of the cylindrical body 12, the liquid-tightness can be reliably maintained and the slidability can be improved.

  The constituent material of the sealing member 56 is not particularly limited. For example, olefin elastomers, styrene elastomers, polyester elastomers, polyurethane elastomers, vulcanized rubbers such as silicone rubber, butyl rubber, and fluororubber, and fluororesin coated on them. It is good to form with things. Instead of the ring-shaped seal member 56, a gasket made of an elastic resin material may be attached to the tip of the filling member 16.

  The outer diameter of the front end portion of the filling member 16 (in the illustrated example, the outer diameter of the seal member 56 assembled to the head portion 50) is the same as or slightly larger than the inner diameter of the body portion 18 of the cylindrical body 12, For example, it is set to about 5-50 mm, and it is more preferable to set to about 10-20 mm. If the outer diameter of the seal member 56 assembled in the head unit 50 is too large, the operating force when rotating the pusher 13 of the drug injection device 10 filled with a high-viscosity drug becomes too large, Operation becomes difficult. Further, if the outer diameter of the seal member 56 assembled in the head portion 50 is too small, it becomes difficult to maintain liquid tightness with the body portion 18 of the cylindrical body 12.

  The shaft portion 52 is smaller in diameter than the insertion hole 30a provided in the shaft 30 of the pusher 13, and is inserted into the insertion hole 30a so as to be slidable in the axial direction. The user grips the grip portion 54 and sucks it. The force when the operation is performed, that is, the operation force in the axial direction from the user input to the grip portion 54 is transmitted to the head portion 50 described above. Since the head portion 50 slidably inserted into the cylindrical body 12 is moved in the axial direction, the overall length of the shaft portion 52 is longer than the overall length of the shaft 30 of the pusher 13.

  In the present embodiment, the shaft portion 52 is separable into a first portion 52A on the distal end side and a second portion 52B on the proximal end side at an intermediate position in the axial direction. Specifically, as shown in FIG. 2, the shaft portion 52 has a fragile portion 58 at an intermediate position in the axial direction. The fragile portion 58 is an annular groove having a V-shaped cross section. That is, the fragile portion 58 is a portion whose strength is relatively smaller than that of the other portion by being formed with a narrower diameter than the other portion by the annular groove having a V-shaped cross section. Therefore, the first portion 52A and the second portion 52B are separable when the fragile portion 58 breaks when a bending stress of a predetermined level or more is applied to the shaft portion 52.

  In a state where the filling member 16 is at a position closer to the distal end side than the most retracted position of the movable range, the fragile portion 58 is positioned closer to the proximal end side than the shaft 30 of the pusher 13 (rear side of the shaft 30). The position of the fragile portion 58 is set so as to be exposed at (1). As a result, after the filling operation of the medicine into the cylindrical body 12 and the air discharging operation are finished, the shaft portion 52 is moved at the position of the fragile portion 58 by applying a bending stress of a predetermined value or more to the shaft portion 52. Can be broken.

  Note that the structure that allows the first portion 52A and the second portion 52B to be separated is not limited to the configuration of the fragile portion 58 described above. For example, when the first part 52A and the second part 52B constituted by different parts are connected by physical engagement such as fitting and screwing, and a tensile stress, bending stress or rotational stress exceeding a predetermined level is applied. In addition, a configuration in which the connection between the first part 52A and the second part 52B is released may be employed.

  The grip portion 54 is a portion that the user grips (picks) and pulls when filling the cylindrical body 12 with a medicine, and is formed in a flat shape wider than the shaft portion 52 in this embodiment. Has been. As shown in FIG. 1, a bottomed recess 60 is provided on the side of the grip 54. The concave portions 60 are provided on both surfaces of the grip portion 54. The concave portion 60 may be provided only on one side surface of the grip portion 54. By providing such a recess 60, when the shaft portion 52 is broken at the weakened portion 58, when the recess 60 is pressed from the side of the grip portion 54, bending stress is easily applied to the shaft portion 52. Therefore, the breaking operation of the shaft portion 52 can be easily performed.

  The shape of the gripping portion 54 may be any shape that can be pulled in the proximal direction when filling the medicine and can be pressed in the radial direction when the shaft portion 52 is broken. The shape which provided the through-hole in the side part may be sufficient. Further, by providing the through hole, the user's finger can be hooked when the filling member 16 is moved backward with respect to the cylindrical body 12.

  As shown in FIGS. 1 and 2, the pharmaceutical injection device 10 according to this embodiment further includes a cover member 62 that covers the periphery of the cylindrical body 12. The cover member 62 has a cylindrical shape with both ends opened, and the cylindrical body 12 can be inserted from the base end side. In the state where the cover member 62 and the guide member 36 are coupled, the cover member 62 is prevented from moving in the axial direction with respect to the cylindrical body 12, but in the state where the cover member 62 and the guide member 36 are separated, the cover member 62 is prevented from moving. The member 62 can be displaced in the axial direction with respect to the cylindrical body 12.

  The cover member 62 has a length that can substantially cover the cylindrical body 12. Preferably, in a state where the cylindrical body 12 is inserted through the cover member 62 and the guide member 36 and the cover member 62 are connected (the state shown in FIG. 2), the distal end (the distal end pipe portion 20) of the cylindrical body 12 is a cover. Projecting from the tip of the member 62.

  As shown in FIG. 6, the cover member 62 includes a fitting portion 64 that fits (contacts) with the outer peripheral portion of the inserted tubular body 12, and an enlarged diameter portion that has an inner diameter larger than the inner diameter of the fitting portion 64. 66. The fitting portion 64 is provided only in a predetermined range that constitutes the base end portion of the cover member 62, and has an inner diameter that is substantially the same as the outer diameter of the cylindrical body 12. A female screw portion 68 to which the guide member 36 can be screwed is provided on the inner periphery of the base end portion of the cover member 62.

  The enlarged diameter portion 66 constitutes a portion (a portion other than the proximal end portion) extending from the distal end portion to the vicinity of the proximal end portion in the cover member 62 and has an inner diameter larger than the outer diameter of the cylindrical body 12. For this reason, in the state where the cylindrical body 12 is inserted through the cover member 62, an annular gap 70 (air) extending in the axial direction between the inner peripheral surface of the cover member 62 and the outer peripheral surface of the cylindrical body 12. Layer) is formed. This void 70 functions as a heat insulating layer. Note that a part or all of the cylindrical body 12, the cover member 62, and the guide member 36 may be integrally formed.

  A protruding portion that partially protrudes is provided on the outer peripheral portion of the cylindrical body 12 or the inner peripheral portion of the cover member 62, and the outer peripheral portion of the cylindrical body 12 and the inner peripheral portion of the enlarged diameter portion 66 of the cover member 62 are provided. Partial contact may be made. Even in this case, the gap 70 is formed between the outer peripheral portion of the cylindrical body 12 and the inner peripheral portion of the enlarged diameter portion 66.

  A protrusion or groove extending in the axial direction may be provided in part on the outer peripheral portion of the cover member 62. This makes it difficult for the user's hand to slip when gripping the cover member 62 during the injection operation.

  As a constituent material of the cover member 62, it can select from what was illustrated as a constituent material of the cylindrical body 12 mentioned above. Further, the cover member 62 itself may be made of a heat-insulating material such as foamed polystyrene. Further, the gap 70 may have a mesh structure or a beam structure. The cover member 62 is desirably transparent enough to allow the medicine in the cylindrical body 12 to be visually recognized. When the scale portion 19 (see FIG. 1) is provided on the outer peripheral surface of the cylindrical body 12 as in this embodiment, the fact that the cylindrical body 12 has transparency means that the cover member 62 is attached to the cylindrical body 12. Since the scale part 19 can be visually recognized in the state which carried out, it is especially useful.

  As shown in FIG. 1, on the proximal end side of the cover member 62, a portion 72 into which the flange portion 22 of the tubular body 12 is fitted is formed in a groove shape corresponding to the flange portion 22. That is, the portion 72 has a pair of straight portions 72a parallel to each other and a pair of arc portions 72b connecting both ends of the straight portion 72a. For this reason, in a state where the guide member 36 and the cover member 62 are coupled, the portion 72 and the flange portion 22 are engaged with each other, whereby relative rotation between the cover member 62 and the cylindrical body 12 is prevented. That is, the portion 72 and the flange portion 22 constitute rotation prevention means for preventing relative rotation in the circumferential direction between the cylindrical body 12 and the cover member 62.

  The means for preventing the relative rotation between the cylindrical body 12 and the cover member 62 is not limited to the configuration shown in FIG. 1. For example, one of the outer peripheral portion of the cylindrical body 12 and the inner peripheral portion of the cover member 62 is provided. A protrusion may be provided, and a groove that engages with the protrusion may be provided on the other, and the relative rotation in the circumferential direction between the cylindrical body 12 and the cover member 62 may be prevented by the engagement between the protrusion and the groove. Good.

  As shown in FIGS. 1 and 2, a plurality of ribs 74 are formed on the outer peripheral portion of the cover member 62 so as to protrude radially outward and extend along the axial direction at intervals in the circumferential direction. In the illustrated example, four ribs 74 are provided at equal intervals in the circumferential direction. Providing such a rib 74 makes it difficult for the user's hand to slip when gripping the cover member 62 for injection operation (rotation operation of the pusher 13).

  FIG. 7 is a view for explaining the relationship between the scale portion 19 provided on the cylindrical body 12 and the rib 74 provided on the cover member 62. In FIG. 7, for convenience of illustration, the cover member 62 is drawn with imaginary lines. As shown in FIG. 7, the circumferential width of the scale portion 19 (the circumferential width of the entire scale portion 19 including the scale line 19 a and the scale number 19 b) is determined by the circumferential spacing of the ribs 74 provided on the cover member 62. Is also small. In addition, the scale portion 19 is disposed between the ribs 74 in a state where the cover member 62 is attached to the tubular body 12 by the rotation preventing means constituted by the portion 72 (see FIG. 1) and the flange portion 22. As described above, the circumferential positions of the cylindrical body 12 and the cover member 62 are defined. Thereby, when the scale part 19 is viewed through the cover member 62 made of a transparent material, the scale part 19 and the rib 74 do not overlap. Therefore, the scale portion 19 is not obstructed by the rib 74, and the scale portion 19 is easy to read.

  In addition, as long as the rib 74 and the scale part 19 do not overlap, five or more ribs 74 may be provided. In this case, the intervals between the ribs 74 do not have to be equal. For example, if the interval between the ribs 74 located on both sides of the scale portion 19 is equal to or greater than the circumferential width of the scale portion 19, The interval may be equal to or smaller than the circumferential width of the scale portion 19.

  As shown in FIGS. 1 and 2, the drug injection device 10 according to the present embodiment has a guide for stably displacing the pusher 13 in the axial direction along with the rotation of the pusher 13 with respect to the cylindrical body 12. A member 36 is provided. As shown in FIG. 6, the guide member 36 has a base portion 78 in which a female screw portion 76 that can be screwed into a male screw portion 34 provided on the shaft 30 of the pusher 13 is formed, and is more than the female screw portion 76. A screw cylinder 82 extending radially outward from the front surface of the base 78 in the distal direction and having an external thread 80 formed on the outer periphery thereof. The female screw portion 76 can be screwed with the male screw portion 34 provided on the pusher 13. The male screw portion 80 provided on the screw cylinder 82 of the guide member 36 can be screwed with the female screw portion 68 provided on the cover member 62.

  In the pharmaceutical injection device 10, the cylindrical body 12 is rotated with the rotation of the pusher 13 relative to the cylindrical body 12 by the female screw portion 76 provided on the guide member 36 and the male screw portion 34 provided on the pusher 13. In contrast, a feed screw structure 15 for displacing the pusher 13 in the axial direction is configured.

  In the present embodiment, the engagement between the male screw portion 34 of the pusher 13 and the female screw portion 76 of the guide member 36 is shallow by lowering the thread of the female screw portion 76 of the guide member 36. With this configuration, when the pressure in the cylindrical body 12 becomes equal to or higher than a predetermined pressure (for example, 5 to 7 MPa) at the time of drug injection, the male screw portion 34 of the pusher 13 that is rotated is changed to the female screw portion of the guide member 36. Get over 76 (screws idle). Therefore, it is possible to prevent the cylindrical body 12 from being damaged due to the pressure in the cylindrical body 12 becoming excessively high when the medicine is injected.

  As a constituent material of the guide member 36, it can select from what was illustrated as a constituent material of the cylindrical body 12 mentioned above.

  In a state where the guide member 36 and the cover member 62 are connected by screw fitting, the flange portion 22 of the cylindrical body 12 is covered with the guide member 36 (specifically, the front end surface of the screw cylinder 82 of the guide member 36) and the cover. It is sandwiched in the axial direction by the member 62 (specifically, the base end face of the fitting portion 64 of the cover member 62). As a result, the guide member 36 is fixed so as not to move relative to the cylindrical body 12 in the axial direction. That is, in the present embodiment, the guide member 36 has not only a function of guiding the movement of the pusher 13 with respect to the cylindrical body 12 but also a function as a connecting means for fixing the cylindrical body 12 and the cover member 62 to each other. Have both.

  The drug injection device 10 according to the present embodiment is basically configured as described above, and its operation and effects will be described below.

  First, a method for filling the drug injection tool 10 with bone cement 86 as an example of a drug will be described. As shown in FIG. 8A, in order to fill the bone cement 86, the pusher 13 and the filling member 16 are inserted into the cylindrical body 12 and the cover member 62 and the guide member 36 are connected. Put it in a state. In this case, the pusher 13 is moved to the proximal end side of the movable range, and the filling member 16 is moved to the most distal side of the movable range.

  Next, the suction port 83 that functions as a nozzle is screwed into the distal end tube portion 20 of the cylindrical body 12 and attached. The proximal end portion of the suction port 83 can be connected to the distal end tube portion 20 by screwing. When the suction port 83 is connected to the distal end tube portion 20 of the cylindrical body 12, the distal end portion of the suction port 83 is buried in the bone cement 86 prepared in the container 84. Note that the attachment of the suction port 83 to the distal end tube portion 20 may be performed before the pusher 13 is inserted into the cylindrical body 12.

  Next, as illustrated in FIG. 8B, the filling member 16 is pulled in the proximal direction with respect to the tubular body 12 in a state where the distal end portion of the suction port 83 is buried in the bone cement 86. When the filling member 16 is pulled in the proximal direction as described above, the bone cement 86 is sucked into the cylindrical body 12 through the suction port 83 and the distal end tube portion 20 as the filling member 16 moves. As a result, as shown in FIG. 8B, the bone cement 86 is filled into the cylindrical body 12. The filling amount of the bone cement 86 into the cylindrical body 12 is, for example, about 5 to 20 mL. Next, the suction port 83 is disconnected from the distal end tube portion 20 of the cylindrical body 12.

  In this case, in the cylindrical body 12, some air exists on the tip end side of the filling member 16. In the state where air is present in the cylindrical body 12, it becomes difficult to discharge the bone cement 86 due to the air acting as a damper, or even if the bone cement 86 can be discharged, the responsiveness is poor. It becomes difficult to accurately control the amount of injection into the bone. For this reason, next, the air discharge operation | work which extracts the air in the cylindrical body 12 is performed.

  In the air discharging operation, as shown in FIG. 9A, the tip of the medicine injection tool 10 is turned upward and the apparatus waits for a while. Then, the air gradually rises in the bone cement 86 and finally goes out above the bone cement 86. 9B, when the pusher 13 is rotated in the circumferential direction with respect to the cylindrical body 12 and advanced, the head 31 of the pusher 13 contacts the base end surface of the head portion 50 of the filling member 16. Then, the filling member 16 is pushed up (advanced) by the pusher 13. Then, the air can be completely discharged from the cylindrical body 12 by advancing the filling member 16 by an amount corresponding to the volume of air existing at the end of filling the bone cement 86.

  When rotating the pusher 13 to discharge the bone cement 86 from the cylindrical body 12, the gripping portion 54 of the filling member 16 is not necessary. Therefore, after the air is discharged from the cylindrical body 12, the filling member 16 is then separated by separating the second portion 52B from the first portion 52A of the filling member 16 as shown in FIG. A separation operation for removing a rear portion from the second portion 52B is performed. In the present embodiment, specifically, by applying a bending stress of a predetermined value or more to the shaft portion 52 of the filling member 16, the shaft portion 52 is bent and broken at the weakened portion 58. As a result, the second portion 52B is separated from the first portion 52A of the filling member 16.

  The filling member 16 is provided with an air discharge passage that extends to the head portion 50 along the axial direction. When the first portion 52A is separated from the second portion 52B, the cylindrical body is interposed via the air discharge passage. 12 may be configured such that the inside and outside air communicate with each other. In the case of this configuration, in the air discharging operation performed after filling the cylindrical body 12 with the medicine, the filling member 16 is moved in a state where the shaft portion 52 of the filling member 16 is separated into the first portion 52A and the second portion 52B. By moving forward, the air in the cylindrical body 12 can be discharged to the outside easily and quickly without the cylindrical body 12 being directed upward.

  When the medicine to be used has such a high viscosity that it is difficult to suck into the cylindrical body 12 by pulling the filling member 16, a syringe 87 with a lock shown in FIG. May be used to fill the cylindrical body 12 with the drug. The distal end of the outer cylinder 90 of the syringe 87 is provided with a tubular nozzle portion 88 and a lock portion 89 that surrounds the nozzle portion 88 and has an internal thread portion 89a formed on the inner peripheral surface. The female thread portion 89a is a double spiral thread, that is, a double thread. As shown in FIG. 11, the male screw portion 27 provided in the distal end tube portion 20 of the cylindrical body 12 is a single screw, but a female screw portion 89 a that is a double screw provided in the lock portion 89 of the syringe 87. Simple screwing is possible. In order to achieve a more complete screwing, the male threaded portion 27 can be a double thread adapted to the female threaded portion 89a.

  When filling the cylindrical body 12 of the drug injection device 10 with the syringe 87 using a syringe 87 so that the drug is so high that it is difficult to fill by suction, first, the pusher 91 is inserted from the outer cylinder 90 of the syringe 87. In a state in which the medicine is removed, the medicine is filled into the outer cylinder 90 from the proximal end side of the syringe 87 with an appropriate small instrument (for example, a thin and small spoon), and the pusher 91 is inserted into the outer cylinder 90. .

  Next, the syringe 87 filled with the medicine is connected to the cylindrical body 12 of the medicine injection tool 10 in a state where the head portion 50 of the filling member 16 is disposed at the forefront. Specifically, the lock portion 89 of the syringe 87 and the distal end tube portion 20 of the cylindrical body 12 are connected by screwing the female thread portion 89a of the lock portion 89 and the male thread portion 27 of the distal end tube portion 20. To do. Then, by pushing the pusher 91 of the syringe 87, the medicine is discharged from the nozzle portion 88, thereby filling the cylindrical body 12 with the medicine.

  Next, an operation method of the drug injection device 10 filled with the bone cement 86 as an example of the drug will be described by taking a case of performing percutaneous vertebroplasty using the drug injection device 10 as an example.

  As shown in FIG. 12, the cylindrical body 12 of the drug injection device 10 and the injection port 94 of the bone cement injection needle 93 punctured into the bone 92 to be injected with the bone cement 86 are connected via the extension tube 100. Link. By using the extension tube 100, the medicine injection tool 10 can be operated with the user's hand retracted outside the X-ray irradiation region.

  Here, the bone cement injection needle 93 includes, for example, a hollow puncture needle 96 made of a metal material, and a handle 98 made of, for example, a resin material fixed to the proximal end portion of the puncture needle 96. Have. An injection port 94 communicating with the lumen (hollow portion) of the puncture needle 96 is provided on the upper portion of the handle 98. One end of the extension tube 100 is provided with a connector 102 that is detachably connected to the injection port 94, and the other end of the extension tube 100 is provided with a connector 104 that is detachable from the distal end tube portion 20 of the cylindrical body 12. ing.

  The extension tube 100 preferably has a configuration in which a thread of Kevlar (registered trademark), nylon, polyphenylene sulfide, stainless steel or the like is wound in a mesh or coil shape on the inside or the outer surface of the flexible tube from the viewpoint of pressure resistance. However, it may be a multi-layer tube in which chemical resistant polypropylene or fluororesin is disposed only on the inner surface. The length of the extension tube 100 is preferably set to about 200 to 500 mm so that the user's hand can be reliably retracted outside the X-ray irradiation region.

  As shown in FIG. 12, the distal end portion of the extension tube 100 is angled so that the medicine injection device 10 connected to the bone cement injection needle 93 can be easily operated via the extension tube 100 (the distal end portion is bent). Is good).

  In FIG. 12, the connector 104 provided at one end of the extension tube 100 is connected to the injection port 94 of the handle 98, and the connector 104 provided at the other end of the extension tube 100 is connected to the distal end tube portion of the cylindrical body 12. 20 is connected. Here, as shown in FIG. 13, a female screw portion 105 made of a single thread is provided on the inner peripheral surface of the connector 104 that can be connected to the distal end tube portion 20 of the cylindrical body 12. On the other hand, as described above, the male screw portion 27 provided in the distal end tube portion 20 is a single thread. Accordingly, in the state where the male screw portion 27 and the female screw portion 105 are completely screwed together (when the connection between the extension tube 100 and the cylindrical body 12 is completed), the positional relationship in the circumferential direction between the cylindrical body 12 and the extension tube 100 is as follows. It will always be the same.

  As shown in FIG. 1, in the present embodiment, the scale portion 19 that is visible through the cover member 62 is provided on the outer peripheral surface of the cylindrical body 12, so that the medicine is injected with the scale portion 19 facing upward. It would be advantageous if the tool 10 could be used. Therefore, in the present embodiment, in the state where the connection between the extension tube 100 and the cylindrical body 12 is completed, the female screw portion is oriented so that the tip portion of the extension tube 100 is directed in the direction opposite to the side where the scale portion 19 is provided. 105 and the male screw portion 27 are designed. With this configuration, when the drug injection tool 10 is connected to the bone cement injection needle 93 via the extension tube 100 as shown in FIG. 12, the distal end portion of the extension tube 100 is directed downward. Since the scale portion 19 provided on the shape body 12 is directed upward, the scale portion 19 can be easily read during use of the pharmaceutical injection device 10.

  When the state shown in FIG. 12 is prepared, the bone cement 86 filled in the drug injection device 10 is discharged and injected into the bone 92 under fluoroscopy. In this injection operation, as shown in FIG. 14, by rotating the pusher 13, the filling member 16 is moved together with the pusher 13 toward the distal end side with respect to the cylindrical body 12. That is, since the filling member 16 is pressed in the distal direction by the pusher 13 at the head portion 50, the filling member 16 is also moved in the distal direction as the pusher 13 moves in the distal direction.

  In this case, the drug injection device 10 prevents rotation of the cylindrical body 12 and the cover member 62 from relative rotation in the circumferential direction (the flange portion 22 of the cylindrical body 12 and the portion 72 of the cover member 62; see FIG. 1). Therefore, even if the pusher 13 is rotated while the cover member 62 is gripped, the cylindrical body 12 can be prevented from being rotated. For this reason, the extension tube 100 or the bone cement injection needle 93 connected to the cylindrical body 12 can be prevented from rotating with the rotation of the pusher 13, and the procedure is not hindered.

  As the head portion 50 of the filling member 16 moves forward in the tubular body 12, the filling chamber in the tubular body 12 is pressurized to a high pressure, and the bone cement 86 is replaced with the distal end tube portion 20, the extension tube 100, and the bone. It is injected into the bone 92 through a cement injection needle 93. The bone cement 86 is injected up to the target injection amount by such a rotation operation on the pusher 13.

  During the injection operation, the periphery of the cylindrical body 12 is covered with the cover member 62, and the gap 70 (see also FIG. 6) formed between the cylindrical body 12 and the cover member 62 functions as a heat insulating layer. Therefore, it is suppressed that body temperature transmits to the bone cement 86 in the cylindrical body 12 through a user's finger at the time of operation. Therefore, the increase rate of the viscosity of the bone cement 86 can be suppressed.

  In the use of the medicine injection device 10 configured as described above, when it is desired to stop the injection suddenly during the injection by the rotation operation of the pusher 13, if the pusher 13 is reversely rotated as shown in FIG. Good. Then, the pressure of the head unit 50 by the head 31 of the pusher 13 is released, so that the pressure in the system is reliably released as the head unit 50 is retracted by the pressure from the bone cement 86. As a result, the injection can be stopped suddenly and accurate injection can be ensured.

  16A and 16B are diagrams illustrating an example of how to grip the handle 14 when the drug injection device 10 is used. In the following description, when the handle 14 is rotated to the right, the pusher 13 can be moved forward to inject the medicine, and when the handle 14 is rotated to the left (reverse rotation), the pusher 13 is moved backward to perform the sudden stop of injection. It shall be possible.

  When the handle 14 is rotated to the right for injecting the medicine, the handle 14 is grasped, and as shown in FIG. 16A, for example, the thumb F1 is placed on the distal end side of the handle body 39, and in particular, the thumb F1 is operated with force applied. The handle 14 is easy to rotate. In this case, in the present embodiment, a plurality of first ribs 40 are provided on the outer peripheral surface of the handle body 39 at intervals in the circumferential direction, and the second ribs 41 are provided only on the outer peripheral surface on the proximal end side of the handle main body 39. Therefore, the rotation operation of the handle 14 for injecting the drug can be easily performed.

  That is, there is a region where the second rib 41 does not exist between the first ribs 40 adjacent to each other on the outer peripheral surface on the front end side of the handle body 39, and the thumb F1 is put on the region, whereby the thumb is placed on the first rib 40. Easy to hook F1. Thereby, since the slip between the handle 14 and the operator's hand is suppressed, the rotational operation force by the operator can be suitably transmitted to the handle 14.

  In particular, in the case of the present embodiment, the outer peripheral surface on the front end side of the handle main body 39 has a tapered shape in which the outer diameter decreases toward the front end side (see FIGS. 4A and 4B). F1 can be easily placed on the outer peripheral surface on the front end side of the handle body 39, and the operability can be further improved. Moreover, since the protrusion height from the outer peripheral surface of the front end side of the handle body 39 increases toward the front end side of the plurality of first ribs 40, the thumb F1 of the operator's hand can be easily caught and the operability can be further improved. .

  When the handle 14 is rotated counterclockwise (reversely rotated) for sudden injection stop, as shown in FIG. 16B, when the handle 14 is operated starting from the middle finger F2, for example, placed on the proximal end side of the handle body 39, It is easy to rotate the handle 14. In this case, in the present embodiment, the plurality of second ribs 41 are provided on the outer peripheral surface of the proximal end side of the handle main body 39 at intervals in the circumferential direction, so that the handle 14 can be easily rotated in the reverse direction. That is, when the middle finger F2 is hooked on the second rib 41, the second rib 41 acts as a slip stopper. Thereby, even during reverse rotation operation, the rotational operation force by the operator can be suitably transmitted to the handle 14.

  In particular, in the case of the present embodiment, the circumferential interval of the second ribs 41 is smaller than the circumferential interval of the first ribs 40, that is, the number of the second ribs 41 is larger than the number of the first ribs 40. Therefore, when the operator grasps the handle 14 and puts the middle finger F2 on the proximal end side of the handle body 39, the middle finger F2 is surely placed on the second rib 41. Therefore, the operator's middle finger F2 is easily hooked, and the operability during the reverse rotation operation is excellent.

  In the case of the present embodiment, the first rib 40 has a length that is at least one half of the axial length of the handle body 39, and the second rib 41 has an axial length of the handle body 39. It has a length of less than half. With this configuration, the rotational operation force when the handle 14 is rotated in reverse by placing the middle finger F2 on the second rib 41 does not have to be so large. The area for placing the thumb F1 can be made relatively large. Thereby, at the time of injecting the medicine, it is easy to apply a force for carrying out the rotation operation by placing the thumb F1 in a relatively wide range on the distal end side of the handle 14.

  The present invention is particularly useful when applied to a drug injection device 10 including a pusher 13 and a filling member 16 as drug delivery means. That is, when the handle 14 is operated to rotate backward while the medicine injection device 10 including the pusher 13 and the filling member 16 is in use, the injection sudden stop (pressure release) can be performed without causing the medicine backflow. Therefore, the structure in which the first rib 40 and the second rib 41 are provided on the handle 14 in the drug injection device 10 having such a filling member 16 makes it possible to smoothly and easily stop the injection without causing the drug backflow. It is excellent in that it can be performed.

  In the handle 14 described above, the first rib 40 extends substantially the entire length of the handle main body 39. However, as in the handle 14a according to the modified example shown in FIG. One rib 40 may extend. In this case, as shown in FIG. 17, the first rib 40 does not exist on the proximal end side of the handle main body 39, and only a plurality of second ribs 41 are arranged at intervals in the circumferential direction.

  In addition, the pusher 13 and the filling member 16 as a medicine delivery means are not restricted to the structure mentioned above. For example, the pusher 13 and the filling member 16 may be configured to be separable. In this case, when the medicine is filled in the cylindrical body 12, the pusher 13 is separated from the filling member 16 and the cylindrical body 12. When the medicine is discharged from the cylindrical body 12, the pusher 13 is inserted into the cylindrical body 12 and the head portion 50 of the filling member 16 is advanced through the pusher 13.

  In the above-described embodiment, the gripping portion 54 of the filling member 16 is gripped and pulled to suck the medicine and fill the cylindrical body 12. It is good also as a structure which fills a chemical | medical agent by the filling member 16 moving to a proximal end direction. In this case, at the position where the pusher 13 is retracted to the position where the male screw part 34 of the pusher 13 and the female screw part 76 of the guide member 36 are released, the tip of the pusher 13 and the filling member 16 The base end portion has a structure that can be engaged or fitted (screwed or the like). Thereby, the filling member 16 can be pulled through the pusher 13.

  Moreover, this invention is not restricted to the structure provided with the pusher 13 and the filling member 16 as a chemical | medical agent delivery means. Therefore, the present invention is applicable even if the medicine delivery means is composed of a single pusher having a male screw formed on the outer peripheral portion.

  In the above description, the present invention has been described with reference to preferred embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Yes.

DESCRIPTION OF SYMBOLS 10 ... Drug injection tool 12 ... Cylindrical body 13 ... Pusher 14, 14a ... Handle 15 ... Feed screw structure 16 ... Filling member 30 ... Shaft 31 ... Head 39 ... Handle body 40 ... 1st rib 41 ... 2nd rib

Claims (6)

A drug injection device that discharges a drug filled inside,
A cylindrical body having a medicine discharge port at the tip and filled with the medicine;
A pusher having a shaft that can be inserted into the hollow portion of the cylindrical body, and a handle for rotating the shaft;
A feed screw structure that displaces the pusher in the axial direction with respect to the tubular body as the pusher rotates with respect to the tubular body;
The handle is
The handle body,
A plurality of first ribs extending in the axial direction on the outer peripheral surface of at least the distal end side of the handle body and arranged at intervals in the circumferential direction;
A plurality of second ribs extending in the axial direction only on the base end side outer peripheral surface of the handle body and arranged at a circumferential interval smaller than a circumferential interval of the plurality of first ribs;
A drug infusion device characterized by that. The drug injection device according to claim 1, wherein
A head portion that can be liquid-tightly inserted into the hollow portion of the cylindrical body on the tip side of the pusher, and a filling member that can be displaced in the axial direction with respect to the pusher.
A drug infusion device characterized by that. The medicine injection device according to claim 1 or 2,
The distal end side outer peripheral surface of the handle body has a tapered shape with an outer diameter decreasing toward the distal end side,
A drug infusion device characterized by that. In the medicine injection device according to any one of claims 1 to 3,
The first rib has a protruding height from the outer peripheral surface of the distal end side of the handle body that increases toward the distal end side.
A drug infusion device characterized by that. In the medicine injection device according to any one of claims 1 to 4,
The first rib extends substantially in the entire axial direction on the outer peripheral surface of the handle body,
The second rib is disposed between each of the first ribs adjacent to each other.
A drug infusion device characterized by that. In the medicine injection device according to any one of claims 1 to 5,
The first rib has a length of one half or more of the axial length of the handle body,
The second rib has a length less than one half of the axial length of the handle body.
A drug infusion device characterized by that.

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