JP4159559B2 - Indwelling needle with storage cylinder - Google Patents

Description

  The present invention relates to an indwelling needle with a storage cylinder that includes an inner needle, a hollow outer needle through which the inner needle is inserted, and a storage cylinder that can be retracted and stored from the outer needle.

  Conventionally, as this type of indwelling needle with a storage cylinder, an inner needle having a cutting edge at the front end, an inner needle hub connected to the rear end of the inner needle, a hollow outer needle through which the inner needle is slidably inserted, The outer needle hub connected to the rear end of the outer needle, the inner needle hub slidably inserted, and the inner needle hub can be accommodated, and the inner needle hub is located behind the accommodation cylinder. Biasing means for biasing, holding means for holding the inner needle in a state exposed to the front of the storage cylinder against the biasing force of the biasing means, release of the holding by the holding means, and release of the inner needle to the storage cylinder There is known an indwelling needle with a storage cylinder that includes a storage means for storing therein (see, for example, Patent Document 1).

  In the thing of the said patent document 1, while the engagement step part which protrudes radially inward is formed in the two circumferential directions of the inner peripheral surface of a storage cylinder as a holding means, and the outer peripheral surface of an inner needle hub is formed. Overhangs are formed at two locations in the circumferential direction so as to protrude radially outward and engage with the front end surface of the engagement step portion. The engagement between the engagement step portion and the overhang portion causes the inner needle to be It is held in a state exposed to the front. Further, in this case, a cam mechanism having an operation portion that is formed in the peripheral wall of the storage cylinder in the front-rear direction and is exposed to the outside of the storage cylinder through the slit is provided as the storage means, and the cam is operated by operating the operation section. The inner needle hub is rotated via the mechanism to release the engagement between the engaging step portion and the overhanging portion, and the inner needle is stored in the storage cylinder by the biasing force of the biasing means.

  Here, the cam mechanism is slidably inserted into the storage cylinder at a portion on the rear side from the engaging step portion, and a pair of sliders having the operation portion formed on the outer surface, and a pair of sliders extending forward from the slider. The operating pin and a cam portion that is formed so that the operating pin comes into contact with the rear end portion of the inner needle hub from the rear and inclines in the circumferential direction with respect to the front-rear direction. Then, by moving the operating portion forward, the operating pin that moves forward together with the slider comes into contact with the cam portion, and the forward pushing force by the operating portion is converted into the rotational force of the inner needle hub, so that the inside of the storage cylinder. The inner needle hub rotates, whereby the engagement between the engaging step portion and the overhanging portion is released, and the inner needle hub is moved rearward of the storage cylinder by a biasing means such as a compression coil spring, so that the inner needle is stored. Housed in a tube.

  According to the indwelling needle with a storage cylinder configured as described above, the inner needle can be easily stored in the storage cylinder, and when the inner needle is stored in the storage cylinder, the inner needle may be accidentally inserted into a finger or the like. Can be prevented.

  However, in this indwelling needle with a storage cylinder, since the operating pin comes into contact with the cam portion of the inner needle hub from the rear side, when the inner needle hub moves rearward by the biasing force of the biasing means, the slider also moves through the operating pin. Move backwards. In order to store the inner needle in the storage cylinder, the inner needle hub moves rearward at least the entire length of the inner needle. Accordingly, the slider also moves backward by at least the entire length of the inner needle. For this reason, it is necessary to lengthen the total length of the slit from which the operation unit is exposed at least as long as the total length of the inner needle so as to allow the slider to move backward. However, if the overall length of the slit is lengthened, blood or the like attached to the inner needle may flow out from the slit after the inner needle is stored in the storage cylinder.

In this case, the operation unit is arranged at the rear part of the storage cylinder in relation to the arrangement position of the slider. Therefore, after gripping and puncturing the front part of the storage cylinder, when storing the inner needle, it is necessary to change the storage cylinder and operate the operation part at the rear, resulting in poor operability. In this case, it is conceivable to form a forward extension on the slider and arrange the operation part at the front part of the storage cylinder. However, in the indwelling needle with the storage cylinder of the above configuration, the operation direction of the operation part is the front. Since it coincides with the puncturing direction, there is a possibility that the inner needle hub may be rotated by operating the operation unit by mistake when puncturing, and the inner needle may be stored in the storage cylinder before puncturing. For this reason, the medical staff needs to work carefully so that it may not operate an operation part, when puncturing.
Japanese Patent No. 2647132 (page 10-11, FIG. 13, FIG. 13a, FIG. 13b)

  In view of the above points, an object of the present invention is to provide an indwelling needle with a storage cylinder that can shorten the overall length of the slit and is easy to use.

  In order to achieve the above object, in the present invention, an inner needle having a cutting edge at the front end, an inner needle hub connected to the rear end of the inner needle, a hollow outer needle through which the inner needle is slidably inserted, An outer needle hub that is connected to the rear end of the outer needle, a cylindrical storage cylinder that is slidably inserted into the inner needle hub and that can store the inner needle, and an inner needle hub that is provided in the storage cylinder. An indwelling needle with a storage cylinder having a biasing means for biasing the rear of the storage cylinder, wherein an engagement step portion projecting radially inward is formed on a part of the inner peripheral surface of the storage cylinder. A protruding portion that protrudes radially outward from a part of the outer peripheral surface of the needle hub and engages with the front end surface of the engaging step portion is formed, and by engagement between the engaging step portion and the protruding portion, The inner needle is held in a state exposed to the front of the storage cylinder, and a longitudinal slit is formed on the peripheral wall of the storage cylinder in the front-rear direction, and the operation needle is exposed to the outside of the storage cylinder through the slit. A mechanism is provided, and the inner needle hub is rotated via the cam mechanism by operating the operation portion, the engagement between the engagement step portion and the overhanging portion is released, and the inner needle is moved into the storage cylinder by the urging force of the urging means. The following items have been improved.

  That is, according to the present invention, the cam mechanism is slidably inserted into the storage cylinder at a portion in front of the engaging step portion, and the operation portion is formed on the outer surface, and the inner surface of the slider has a diameter. The engagement element is formed so as to protrude inward in the direction, and the cam portion is inclined in the circumferential direction with respect to the front-rear direction formed so that the engagement element comes into contact with the outer peripheral surface of the inner needle hub from the front. It is characterized by doing.

  According to this configuration, when the operation unit is moved rearward along the slit, the slider moves rearward, and the engaging element abuts against the cam unit and pushes it. Thereby, the pushing force to the back of the slider is converted into the rotational force of the inner needle hub, and the engagement between the engagement step portion and the overhang portion is released. Therefore, the inner needle hub moves rearward of the storage cylinder by the biasing force of the biasing means, and the inner needle is stored in the storage cylinder.

  Further, according to the present invention, the slider engaging element is configured to come into contact with the cam portion of the inner needle hub from the front side, so that the relative movement of the engaging element to the front side is allowed with respect to the cam portion. However, the slider does not move backward even if it is moved rearward of the storage cylinder by the biasing means. For this reason, the full length of the slit can be shortened, and the outflow of blood or the like attached to the inner needle from the slit can be suppressed when the inner needle is stored in the storage cylinder. In addition, since the slider is slidably inserted in the storage cylinder at a portion in front of the engaging step portion, the operation portion formed on the outer surface of the slider is disposed in the front portion of the storage cylinder. . For this reason, after grasping and puncturing the front part of the storage cylinder, the inner needle can be stored in the storage cylinder by operating the operation unit without changing the storage cylinder. In addition, since the operation direction of the operation unit is rearward and opposite to the puncture direction, it is possible to prevent the operation unit from being erroneously operated at the time of puncture, which is convenient.

  Here, in the indwelling needle with a storage cylinder, the front end portion of the inner needle hub is generally exposed from the front end of the storage cylinder so that it can be fitted to the outer needle hub. In such a configuration, if the inner needle hub is accidentally rotated through the outer needle hub when the patient is punctured with the indwelling needle with the storage cylinder, the engagement step portion and the tensioning portion are not required to be operated. The engagement with the protruding portion is released, and the inner needle is stored in the storage cylinder. Therefore, medical personnel need to puncture carefully so as not to rotate the inner needle hub via the outer needle hub.

  In this case, a straight portion that is straight in the front-rear direction is formed at the front end portion of the cam portion, and a stopper portion that is formed by a protrusion that faces the straight portion with a gap in the circumferential direction is provided on the outer peripheral surface of the inner needle hub. If the engaging element is located between the straight part and the stopper part when the engaging step part and the overhanging part are engaged, the inner needle is interposed via the outer needle hub. Even if a rotational force acts on the hub, the rotational force is received by the engagement member sandwiched between the straight portion and the stopper portion, so that the inner needle hub can be prevented from rotating via the outer needle hub. Is advantageous.

  Also, the slider is formed in an annular shape, a flange portion is formed at the rear end portion of the inner needle hub, the overhang portion is formed on the outer periphery of the flange portion, and a compression coil spring is used as a biasing means, and the slider and the flange portion In order to move the slider backward by operating the operating portion, a force greater than the urging force of the compression spring is required. For this reason, the operation of the operation unit unintended by the medical staff can be prevented, which is advantageous.

  An embodiment of the present invention will be described with reference to FIGS. 1 is an explanatory view showing a disassembled state of an indwelling needle with a storage cylinder according to the embodiment, FIG. 2 is an explanatory view showing a part of the embodiment in cross section, FIG. 3 is an explanatory view showing an operation of an operation unit, and FIG. 4 is an explanatory view showing a state in which the inner needle hub is rotated, FIG. 5 is an explanatory view showing a state in which the inner needle is stored in the storage cylinder, and FIG. 6 is an explanatory view showing an inner needle hub of another embodiment. is there.

  As shown in FIGS. 1 and 2, the indwelling needle with a storage cylinder 1 according to the embodiment of the present invention includes an inner needle 2 having a blade edge 2a at the front end and an inner needle hub 3 connected to the rear end, and a rear end. The outer needle 4 is provided with the outer needle hub 4a and the storage cylinder 5 for storing the inner needle 2. The storage cylinder 5 includes a cylinder main body 51 and a cap 52 coupled to the front end portion of the cylinder main body 51. Engagement step portions 51 a and 51 a are formed on the inner peripheral surface of the cylinder body 51 at two locations in the circumferential direction that project radially inward. A slit 52 a that is long in the front-rear direction is formed on the side wall of the cap 52. An opening 52 b is formed in the front end wall of the cap 52.

  The outer needle 4 is formed hollow, and the inner needle 2 is slidably inserted. The inner needle hub 3 is slidably inserted into the storage cylinder 5, and the front end portion 3 a of the inner needle hub 3 is exposed in front of the cap 52 through the opening 52 b. The outer needle hub 4 a is fitted on the front end portion 3 a of the inner needle hub 3. A flange portion 3 b is formed at the rear end of the inner needle hub 3. On the outer periphery of the flange portion 3b, two protruding portions 31, 31 in the circumferential direction are formed that protrude radially outward and engage with the front end surfaces of the engaging step portions 51a, 51a of the cylinder body 51. The inner needle 2 is held in a state exposed to the front of the storage cylinder 5 by the engagement of each engagement step portion 51 a and each overhang portion 31.

  An annular slider 6 that is slidably inserted through the inner needle hub 3 is slidably inserted into the storage cylinder 5 at a portion in front of the engagement step portion 51a. A knob-like operation portion 61 is formed on the outer peripheral surface of the slider 6 so as to be exposed to the outside of the storage cylinder 5 through the slit 52a. Further, on the inner peripheral surface of the slider 6, two engaging elements 62, 62 projecting inward in the radial direction are formed. On the outer peripheral surface of the inner needle hub 3, cam portions 32, 32 are formed in two circumferential directions composed of ridges inclined in the circumferential direction with respect to the front-rear direction. The combination 62 is in contact with the front. A straight portion 32 a that is straight in the front-rear direction is formed at the front end of each cam portion 32. Further, on the outer peripheral surface of the inner needle hub 3, each stopper portion 33 is formed of a ridge facing the straight portion 32a with a space in the circumferential direction. Each engagement element 62 is sandwiched between the straight portion 32a and the stopper portion 33 when the engagement step portions 51a and the overhang portions 31 are engaged with each other. Further, a compression coil spring 7 as a biasing means is provided between the slider 6 and the flange portion 3b.

  When using the indwelling needle 1 with a storage cylinder of the embodiment, first, the patient is punctured with the indwelling needle 1 with a storage cylinder. Next, only the inner needle 2 is removed while the patient is punctured with the outer needle 4. And as shown with the broken line of FIG. 3, the operation part 61 is moved back along the slit 52a. Since the operation part 61 is provided in the front part of the storage cylinder 5, the medical worker can operate the operation part 61 without holding the storage cylinder 5 after holding and puncturing the front part of the storage cylinder 5. .

  When the operation portion 61 is moved rearward, each engagement element 62 of the slider 6 is separated from between the straight portion 32a of each cam portion 32 and the stopper portion 33 and moved to an inclined portion of each cam portion 32. Each engaging element 62 presses each cam portion 32, and the pushing force to the rear of the operation portion 61 is converted into the rotational force of the inner needle hub 3.

  When the inner needle hub 3 rotates, as shown in FIG. 4, the engagement between the overhang portions 31 and the engagement step portions 51a is released. Then, as shown in FIG. 5, the inner needle 2 and the inner needle hub 3 are moved and stored behind the storage cylinder 5 by the urging force of the compression coil spring 7. Thereafter, an infusion tube (not shown) is connected to the outer needle hub 4a punctured by the patient, and a drug solution is introduced.

  According to the indwelling needle with a storage cylinder 1 of the embodiment, each engaging element 62 is configured to come into contact with each cam part 32 from the front, so that each engaging element 62 moves forward relative to each cam part 32. Even if the inner needle hub 3 is moved rearward of the storage cylinder 5 by the biasing force of the compression coil spring 7, the slider 6 does not move rearward together with the inner needle hub 3. For this reason, unlike the conventional product, there is no need to lengthen the entire length of the slit 52a for exposing the operating portion 61 to the outside of the storage cylinder 5, and when the inner needle 2 is stored in the storage cylinder 5, The outflow of blood or the like attached to the inner needle 2 can be suppressed.

  Further, in a state where each engagement step portion 51 a and each overhang portion 31 are engaged, between the straight portion 32 a of each cam portion 32 formed on the outer periphery of the inner needle hub 3 and the stopper portion 33. Since each engagement element 62 formed on the inner surface of the slider 6 is sandwiched, unless the operation part 61 is moved backward and the engagement elements 62 are separated from between the straight part 32 a and the stopper part 33, The inner needle hub 3 cannot rotate within the storage cylinder 5. For this reason, even if a medical worker accidentally applies a rotational force to the outer needle hub 4a when puncturing the patient with the indwelling needle 1 with a storage cylinder, the inner needle hub 3 is not connected to the outer needle hub 4a. It does not rotate, and it is possible to prevent the inner needle 2 from being stored in the storage cylinder 5 by unintentionally releasing the engagement between the engagement step portions 51 a and the overhang portions 31. Further, since the operation direction of the operation unit 61 is backward and opposite to the puncture direction, it is possible to prevent the operation unit 61 from being erroneously operated during puncture.

  By the way, when the engagement between each engagement step portion 51 a and each overhang portion 31 is released and the inner needle hub 3 moves rearward of the storage cylinder 5 by the urging force of the compression coil spring 7, each stopper portion 33. When the front end surface of each engagement element 62 comes into contact with and engages with the rear end surface, the rearward movement of the storage cylinder 5 of the inner needle hub 3 is prevented. Therefore, when the engagement between each engagement step portion 51a and each overhang portion 31 is released, each engagement element 62 is configured to be sufficiently separated from each stopper portion 33 in the circumferential direction, or Even if the rear end surface of each stopper portion 33 is inclined or the front end surface of each engagement element 62 is inclined so that the rear end surface of each stopper portion 33 and the front end surface of each engagement element 62 come into contact with each other, they do not engage with each other. It is desirable to do so.

  In the embodiment, each cam portion 32 is formed with a protrusion, but the present invention is not limited to this. For example, as shown in FIG. 6, a wide recess in the circumferential direction is formed on the outer peripheral surface of the inner needle hub 3. A portion 32b may be formed, and the cam portion 32 may be configured by a stepped portion at the rear end of the recessed portion 32b. In this case, the stopper portion 33 is provided in the recessed portion 32b.

Explanatory drawing which shows the state which the indwelling needle with the storage cylinder of embodiment decomposed | disassembled. Explanatory drawing which showed a part of embodiment in the cross section. Explanatory drawing which showed operation of the operation part. Explanatory drawing which shows the state which the inner needle hub rotated. Explanatory drawing which shows the state in which the inner needle was accommodated in the storage cylinder. Explanatory drawing which showed the inner needle hub of other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Indwelling needle with a storage cylinder, 2 ... Inner needle, 2a ... Cutting edge, 3 ... Inner needle hub, 3b ... Flange part, 31 ... Overhang part, 32 ... Cam part, 32a ... Straight part, 33 ... Stopper part, 4 DESCRIPTION OF SYMBOLS ... Outer needle, 4a ... Outer needle hub, 5 ... Storage cylinder, 51a ... Engagement step part, 52a ... Slit, 6 ... Slider, 61 ... Operation part, 62 ... Engagement element, 7 ... Compression coil spring.

Claims (3)

An inner needle having a cutting edge at the front end, an inner needle hub connected to the rear end of the inner needle, a hollow outer needle slidably inserted through the inner needle, and an outer needle connected to the rear end of the outer needle A needle hub, a cylindrical storage cylinder that slidably inserts the inner needle hub and accommodates the inner needle, and a biasing means that is provided in the storage cylinder and biases the inner needle hub rearward. An indwelling needle with a storage cylinder,
An engagement step portion is formed on the inner circumferential surface of the storage cylinder so as to project radially inwardly, and is projected radially outward on a portion of the outer peripheral surface of the inner needle hub in the radial direction. An overhanging portion that engages with the front end surface of the storage tube is formed, and the engagement between the engagement step portion and the overhanging portion holds the inner needle in a state of being exposed to the front of the storage tube, and the peripheral wall of the storage tube A longitudinal slit is formed in the front-rear direction, and a cam mechanism having an operation portion exposed to the outside of the storage cylinder through the slit is provided, and the inner needle hub is rotated via the cam mechanism by operation of the operation portion. In the case where the inner needle is stored in the storage cylinder by the biasing force of the biasing means by releasing the engagement with the overhanging portion,
The cam mechanism is slidably inserted in the storage cylinder at a portion in front of the engagement step portion, and protrudes radially inward on the inner surface of the slider having the operation portion formed on the outer surface. And the cam portion that is inclined in the circumferential direction with respect to the front-rear direction and is formed so that the engagement member comes into contact with the outer peripheral surface of the inner needle hub from the front. An indwelling needle with a storage cylinder. A straight portion that is straight in the front-rear direction is formed at the front end portion of the cam portion, and a stopper portion is formed on the outer peripheral surface of the inner needle hub that is opposed to the straight portion with an interval in the circumferential direction. And
2. The storage cylinder according to claim 1, wherein the engagement element is positioned between the straight portion and the stopper portion when the engagement step portion and the overhang portion are engaged with each other. Indwelling needle. The slider is formed in an annular shape,
A flange portion is formed at a rear end portion of the inner needle hub, and the overhang portion is formed on an outer periphery of the flange portion,
The indwelling needle with a storage cylinder according to claim 1 or 2, wherein the biasing means is a compression coil spring and is contracted between the slider and the flange portion.

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