自锁式注射器 发明领域 FIELD OF THE INVENTION
本发明涉及一种自锁式注射器, 属于医疗器械领域。 The invention relates to a self-locking syringe and belongs to the field of medical equipment.
背景技术 Background technique
国内外已有许多专利提供了一次性使用的自锁式注射器,但多数因 结构复杂、 制造成本高, 或因使用时感到不便, 而未能广泛得到使用。 英国星赛瑞公司申请的申请号为 PCT/GB97/01889、 CN97193570.X的 Many patents at home and abroad have provided disposable self-locking syringes, but most of them have not been widely used due to the complicated structure, high manufacturing cost, or inconvenience during use. The application number of the British Xing Seri company is PCT / GB97 / 01889, CN97193570.X
"注射器"专利, 属自锁式一次性注射器。其主要特征是在芯杆前端紧 靠活塞处设置锁定装置,该锁定装置为挠性的十字型卡板或两个挠性连 接的倒钩。使用后回抽芯杆时,此锁定装置被针筒壁上的阻塞环(或槽) 阻挡, 从而将锁定装置及橡胶活塞拦截在针筒顶部, 不能拉出, 并使推 杆与卡板分离。此专利结构有较好的一次性使用特性,在国外已成为第 二代 (自毁式) 注射器的典型产品。 但此专利存在如下两个问题:The "syringe" patent is a self-locking disposable syringe. The main feature is that a locking device is provided at the front end of the core rod next to the piston, and the locking device is a flexible cross-shaped clamping plate or two flexible connected barbs. When the core rod is returned after use, the locking device is blocked by the blocking ring (or groove) on the syringe wall, so that the locking device and the rubber piston are blocked on the top of the syringe, cannot be pulled out, and the push rod is separated from the card plate. . This patent structure has better single-use characteristics and has become a typical product of the second generation (self-destructing) syringes abroad. But this patent has the following two problems:
1. 结构复杂, 模具寿命短, 成本高。 如该专利文件所表述, 参看 专利说明书图 18, 其包括锁定装置 (如十字卡板) 在内的芯杆头部结 构较为复杂, 从而使模具的结构复杂而单薄, 刚性较差, 这将会影响到 模具的使用寿命。虽然该专利第二部分为此提出了拼镶模具结构来解决 此问题, 但由此引起的生产投入和成本增加是不能忽视的。 1. Complicated structure, short mold life and high cost. As stated in the patent document, referring to FIG. 18 of the patent specification, the core rod head structure including the locking device (such as a cross card) is more complicated, so that the structure of the mold is complicated and thin, and the rigidity is poor. Affects the service life of the mold. Although the second part of this patent proposes a mosaic mold structure to solve this problem, the increase in production investment and cost caused by this cannot be ignored.
2. 连接件抗扭转强度低, 容易因意外断裂而报废。 为了防止强制 回抽时使锁定装置(如十字卡板)拉过阻塞环而丧失一次性性能, 此专 利在卡板与推杆间设置了一薄弱小圆柱连接件 18。 使用实践证明, 此 连接件在一定的拉力下很易断裂,从而保证了注射器不能再次使用。然 而此连接件结构不但造成抗拉强度低,而且其抗扭转强度更低。若在生 产或使用时不经意地转动推杆, 即可能导致薄弱连接件 18意外断裂而 报废; 而且在注塑、 组装等生产过程中, 易因断裂而影响成品率, 而这 正是影响生产成本的一个重要因素。 2. The connector has low torsional strength and is easily scrapped due to accidental fracture. In order to prevent the locking device (such as the cross card board) from pulling through the blocking ring and losing the disposable performance during the forced withdrawal, this patent has provided a thin and small cylindrical connecting member 18 between the card board and the push rod. Practice has proved that this connector is easily broken under a certain tensile force, thereby ensuring that the syringe cannot be used again. However, this connector structure not only results in low tensile strength, but also lower torsional strength. If the pusher is accidentally turned during production or use, it may cause the weak connection piece 18 to break unexpectedly and be discarded; and during the production process such as injection molding and assembly, it is easy to affect the yield due to the break, which is exactly what affects the production cost An important factor.
发明内容 Summary of the Invention
为解决上述问题,本发明的目的是提供一种使用效果好,成本低的
注射器的自锁结构。 In order to solve the above problems, an object of the present invention is to provide a high-efficiency and low-cost Self-locking structure of the syringe.
本发明是这样实现的: The invention is implemented as follows:
一种自锁式注射器, 由针头、 ti .」、 活塞和芯杆等部件组成, 芯杆 的前部为连接头和前推板, 后部为推杆, 其特征在于: A self-locking syringe is composed of a needle, ti. ", A piston and a core rod. The front portion of the core rod is a connector and a front push plate, and the rear portion is a push rod. Its characteristics are:
芯杆前端设有一锁止片, 该锁止片位于活塞与芯杆的前推板之间, 锁止片是独立可拆分的零件,设有中心孔,该中心孔直径大于芯杆前端 与橡胶活塞连接的连接头的外圆直径, 其最大自由外径略大于针筒内 径;针筒前部内壁设有一与锁止片相应的阻力环,该阻力环径向截面呈 单一锯齿状,锯齿前端面与针筒壁夹角较小,后端面与针筒壁夹角较大。 The front end of the core rod is provided with a locking piece, which is located between the piston and the front push plate of the core rod. The locking piece is an independent and detachable part with a central hole having a diameter larger than that of the front end of the core rod and The outer diameter of the outer diameter of the connector connected by the rubber piston is slightly larger than the inner diameter of the syringe; the inner wall of the front part of the syringe is provided with a resistance ring corresponding to the locking piece, and the radial cross section of the resistance ring is single zigzag, zigzag The angle between the front end surface and the cylinder wall is small, and the angle between the rear end surface and the cylinder wall is large.
优选的锁止片形式是:锁止片是平板圆环的外缘上, 向后侧一体设 置多个弹性卡爪。 The preferred form of the locking piece is that the locking piece is on the outer edge of the flat ring, and a plurality of elastic claws are integrally provided to the rear side.
锁止片可选用的另一种形式是:锁止片是中心厚、边缘薄的片状环, 前端面是锥面, 后端面是平面, 前面锥面的外边缘设有圆弧倒角, 锁止 片的外圆被切去至少三个弦, 形成至少三个爪。 Another form of locking piece is optional: the locking piece is a sheet ring with a thick center and a thin edge, the front end face is a tapered surface, the rear end face is a flat surface, and the outer edge of the front tapered surface is provided with a rounded chamfer, At least three strings are cut out of the outer circle of the locking piece to form at least three claws.
芯杆前端与活塞配合的圆柱头与颈部的直径相差小,使活塞与芯杆 的拉脱力大于注射器使用及检测中的最大拉力,而小于阻力环对锁止片 的阻力, 实现了使芯杆与橡胶活塞拉脱分离方案。 The diameter difference between the cylindrical head and the neck of the front end of the core rod and the piston is small. Pull-separation scheme of rod and rubber piston.
芯杆可设计成可拉断的形式:推杆径向断面为十字型,推杆和前推 板的连接为两个呈中心对称的可拉断的连接柱。 The core rod can be designed to be breakable: the radial cross section of the push rod is cross-shaped, and the connection between the push rod and the front push plate is two centrally symmetrical breakable connecting posts.
本发明在针筒前部内壁设一阻力环, 阻力环呈锯齿状,前端与针筒 壁夹角较小, 后端与针筒壁夹角较大。注射器使用后, 锁止片越过阻力 环,如欲将芯杆拉出重复使用时, 由于锁止片受到轴向拉力时在阻力环 作用下, 会压向针筒壁, 从而阻止锁止片及活塞越过阻力环, 而芯杆被 拉出活塞, 或芯杆的推杆被拉断, 造成结构破坏, 无法再次使用, 从而 实现了一次性使用的要求。 In the present invention, a resistance ring is provided on the inner wall of the front of the syringe. The resistance ring is sawtoothed, and the angle between the front end and the wall of the syringe is small, and the angle between the rear end and the wall of the syringe is large. After the syringe is used, the locking piece passes over the resistance ring. If the core rod is to be pulled out for repeated use, the locking piece will be pressed against the syringe wall under the action of the resistance ring when the locking piece is subjected to axial tension, thus preventing the locking piece and the The piston passes the resistance ring, and the core rod is pulled out of the piston, or the push rod of the core rod is broken, causing structural damage and unable to be used again, thereby fulfilling the requirement of one-time use.
本发明的最大特征是: 将起阻塞作用的锁定装置与芯杆分体设置, 即将一个可拆分的锁止片置于橡胶活塞与芯杆推板之间。此方案优化了 锁定装置的结构, 从而降低了生产成本。 The biggest feature of the present invention is that: the locking device that functions as a block is separated from the core rod, that is, a detachable locking piece is placed between the rubber piston and the core rod push plate. This solution optimizes the structure of the locking device, thereby reducing production costs.
附图说明
图 1是本发明使用后活塞被锁住、 芯杆拉脱的状态示意图; 图 2是本发明针筒的结构示意图; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a state in which a piston is locked and a core rod is pulled out after use according to the present invention; FIG. 2 is a schematic structural diagram of a syringe of the present invention;
图 3是本发明阻力环的局部示意图; 3 is a partial schematic view of a resistance ring of the present invention;
图 4是本发明芯杆的结构示意图; 4 is a schematic structural diagram of a core rod according to the present invention;
图 5是本发明另一种芯杆结构的示意图; 5 is a schematic diagram of another core rod structure according to the present invention;
图 6是本发明一种优选的锁止片的结构示意图; 6 is a schematic structural diagram of a preferred locking piece of the present invention;
图 7是本发明另一种较简单的锁止片的结构示意图; 7 is a schematic structural diagram of another relatively simple locking piece according to the present invention;
图 8是本发明装配好后、 使用之前的状态示意图; 8 is a schematic diagram of the state of the present invention after assembly and before use;
图 9是使用本发明抽满药液的示意图; FIG. 9 is a schematic diagram of pumping a full liquid medicine using the present invention; FIG.
图 10是使用本发明注射操作完毕, 实现自锁状态的示意图; 图 11是本发明注射操作完毕, 如欲重复使用, 回拉芯杆造成芯杆 与活塞分离的状态示意图。 Fig. 10 is a schematic diagram of the self-locking state after the injection operation of the present invention is completed. Fig. 11 is a schematic diagram of the state of the core rod and the piston being separated when the core rod is pulled back for re-use after the injection operation of the present invention is completed.
图 12是图 11中釆用图 5的芯杆, 被拉断后的示意图。 FIG. 12 is a schematic diagram of the core rod of FIG. 5 after being pulled off.
具体实施方式 detailed description
以下结合附图和实施例对本发明进行详细的说明。 The present invention is described in detail below with reference to the drawings and embodiments.
图 1是本发明自锁式注射器的结构示意图,所有附图中均未绘出注 射针头。图中显示该注射器使用后活塞 4及锁止片 3被针筒 1上的阻力 环 14阻挡, 不能随芯杆 2回抽, 从而使该注射器无法再次使用, 实现 了一次性使用的要求。 FIG. 1 is a schematic structural diagram of the self-locking syringe of the present invention, and the injection needle is not shown in all the drawings. The figure shows that after the syringe is used, the piston 4 and the locking piece 3 are blocked by the resistance ring 14 on the syringe 1 and cannot be withdrawn with the core rod 2, thereby making the syringe unusable and fulfilling the requirements for one-time use.
图 2是本发明的针筒 2的结构示意图。 针筒 2前部的标准锥体 11 用以与注射针头相配合, 针筒 2的中部是筒体 12, 在筒体 12后端翼板 17上设置有自身安全限位挡板 13。 在筒体 12的内壁 15前端设置有阻 力环 14, 其截面呈单一锯齿形, 如图 3所示, 前坡面 141与内壁 15的 夹角 α较小, 可以为 100° ~110° , 后端面 142与内壁 15的夹角 β较 大, 可以为 175 ° 左右。 这种结构一方面是使注射器在推注药液时使阻 力变化较小, 而使回拉锁止片时, 受到阻力环作用阻力最大, 并便于生 产。 在筒体 15后端设置防脱环 16, 其截面形状与阻力环 14完全相同。 Fig. 2 is a schematic structural view of a syringe 2 of the present invention. The standard cone 11 at the front of the syringe 2 is used to cooperate with the injection needle. The middle of the syringe 2 is a barrel 12. A rear end flap 17 of the barrel 12 is provided with its own safety limit baffle 13. A resistance ring 14 is provided at the front end of the inner wall 15 of the cylinder 12, and its cross-section has a single zigzag shape. As shown in FIG. 3, the angle α between the front slope surface 141 and the inner wall 15 is small, and can be 100 ° to 110 °. The angle β between the end surface 142 and the inner wall 15 is large, and may be about 175 °. On the one hand, this structure makes the resistance change smaller when the syringe is injecting the medicinal solution, and makes the resistance of the resistance ring to the maximum when pulling back the locking piece, which is convenient for production. A detachment prevention ring 16 is provided at the rear end of the cylinder 15, and its cross-sectional shape is exactly the same as the resistance ring 14.
结合图 4所示, 安全限位卡板 131由薄膜板 13.3与翼片 17相连, 从而使卡板 131可以由向上竖直位置向后转动 180° 至向下垂直位置,
进入芯杆 2上的槽 25中将芯杆 2卡住不能向前推动。 As shown in FIG. 4, the safety limit card 131 is connected to the wing 17 by a thin-film plate 13.3, so that the card 131 can be rotated backward from an upright position by 180 ° to a down vertical position. The core rod 2 is stuck in the groove 25 on the core rod 2 and cannot be pushed forward.
如图 4所示, 芯杆 2最前端是与橡胶活塞 4配合的圆柱头 21, 其 特征是此圆柱头与颈部 22的直径相差小, 以便在回抽芯杆 2、锁止片 3 被阻力环 14限制无法移动时, 实现芯杆 2与活塞 4分离。 但此分离力 应大于正常抽注药液及检测时的回抽力, 使芯杆 2在正常使用状态时, 不会与活塞 4分离。 芯杆 2的十字筋板上制有三角形槽 25用以与针筒 后端的安全卡板 13禊合, 这样, 在备用状态下, 可防止因误推芯杆造 成注射器自锁而失效。 槽 25前斜面 251与轴线夹角较小 (约 30° ), 后端面 252与轴线垂直。后筋板 26较前筋板 24窄, 以方便正常使用时 安全限位机构自动解除对芯杆的运动限制, 见后面的说明。 As shown in FIG. 4, the foremost end of the core rod 2 is a cylindrical head 21 that cooperates with the rubber piston 4, which is characterized in that the diameter of the cylindrical head and the neck 22 is small so that the core rod 2 and the locking piece 3 are pulled back. When the resistance ring 14 is restricted from moving, the core rod 2 is separated from the piston 4. However, this separation force should be greater than the normal pumping liquid and the withdrawal force during detection, so that the core rod 2 will not be separated from the piston 4 in the normal use state. A triangular groove 25 is made on the cross rib plate of the core rod 2 to fit with the safety card 13 at the rear end of the syringe. In this way, in the standby state, the syringe can be prevented from failing due to the self-locking of the core rod by mistake. The angle between the front inclined surface 251 of the groove 25 and the axis is small (about 30 °), and the rear end surface 252 is perpendicular to the axis. The rear tendon plate 26 is narrower than the front tendon plate 24 to facilitate normal use. The safety limit mechanism automatically releases the movement restriction of the core rod, see the description below.
锁止片 2是本发明的关键,使用中既要求推注时能轻便地推过阻力 环, 回抽芯杆时又能被阻力环 14牢固卡紧。 图 6是一种优选的锁止片 3的结构示意图, 锁止片由基盘 33及多个 (大于 3个) 略为外翻的花 瓣形卡爪 31组成。基盘 33外径略小于阻力环内径, 以便无阻碍的通过 阻力环,其内孔 32大于芯杆 2头部圆柱 21的外径, 以便使用后当锁止 片 3被阻力环 14卡住时, 芯杆的圆柱头 21能从锁止片 3的基盘 33的 内孔 32中通过, 实现芯杆与活塞的分离。卡爪 31顶部 311较薄, 逐渐 向根部 312加厚。 顶部 311前端面是平直面, 能被阻力环 14的前坡面 141挡住, 卡爪 31 的外表面为光滑斜面, 并具有弹性, 便于芯杆前推 时, 锁止片 3顺利越过阻力环 14。 因为瓣形卡板的最大外径略大于针 筒 1的内径,所以组装后卡爪被压缩而使其前端 311向心收缩,而贴紧 针筒 1的内壁 15。 向前推动芯杆 2使锁止片 3通过阻力环 14时, 该结 构的最大特点是卡爪 31的变形量只等于阻力环高度 (约 0.1mm左右) 这使推注阻力变化很小, 因而在使用时, 不会因推注力变化过大, 造成 注射速度突变, 而使患者感到疼痛。而对比专利 CN97193570.X实际上 采用的十字卡板由于必须产生足够量的轴向变形,来使其外径减小到阻 塞环的内径尺寸, 因而阻塞环的阻力较大, 在使用时, 容易引起注射速 度突变而使患者感到疼痛。 虽然本发明的单片多瓣结构卡爪锁止片 3 的结构较上述对比专利的十字片复杂,但由于本发明中锁止片 3与芯杆
2是分别制造的, 显著地降低了模具的复杂程度, 延长了模具的使用寿 命, 从而降低成本。 The locking piece 2 is the key of the present invention. In use, it is required that the resistance ring can be pushed through the resistance ring lightly during bolus injection, and can be firmly locked by the resistance ring 14 when the core rod is returned. FIG. 6 is a schematic structural diagram of a preferred locking piece 3. The locking piece is composed of a base plate 33 and a plurality of (greater than three) petal-shaped claws 31 which are slightly turned out. The outer diameter of the base plate 33 is slightly smaller than the inner diameter of the resistance ring so as to pass through the resistance ring without hindrance. The inner hole 32 is larger than the outer diameter of the cylinder 21 of the head of the core rod 2 so that when the locking piece 3 is caught by the resistance ring 14 after use. The cylindrical head 21 of the core rod can pass through the inner hole 32 of the base plate 33 of the locking piece 3 to achieve separation of the core rod from the piston. The top portion 311 of the claw 31 is thinner and gradually thickens toward the root portion 312. The front end surface of the top portion 311 is flat and can be blocked by the front slope surface 141 of the resistance ring 14. The outer surface of the claw 31 is a smooth inclined surface and has elasticity, so that when the core rod is pushed forward, the locking piece 3 smoothly passes the resistance ring 14 . Because the maximum outer diameter of the petal-shaped clamp plate is slightly larger than the inner diameter of the syringe 1, the jaws are compressed to compress the front end 311 of the syringe 1 and compress the inner wall 15 of the syringe 1 after assembly. When the core rod 2 is pushed forward and the locking piece 3 passes through the resistance ring 14, the biggest feature of this structure is that the deformation amount of the claw 31 is only equal to the height of the resistance ring (about 0.1mm), which makes the change in the bolus resistance very small, so During use, the patient will not feel pain due to the abrupt change in the bolus force, which will cause a sudden change in injection speed. However, the cross card actually used in the comparative patent CN97193570.X must generate sufficient axial deformation to reduce its outer diameter to the inner diameter size of the blocking ring, so the resistance of the blocking ring is large, and it is easy to use it. Sudden changes in injection speed can cause pain to patients. Although the structure of the single-piece multi-lobed claw locking piece 3 of the present invention is more complicated than the cross piece of the above-mentioned comparative patent, the locking piece 3 and the core rod in the present invention 2 is manufactured separately, which significantly reduces the complexity of the mold, prolongs the service life of the mold, and thus reduces costs.
另一种较简单的锁止片 3 ' 的结构如图 7所示, 锁止片 3 ' 是中心 厚、 边缘薄的片状环, 形状如一中空的浅盘。 前端面 33 ' 是锥面, 后 端面 34 ' 是平面, 前面锥面 33 ' 的外边缘设有圆弧倒角。 锁止片 3的 外圆被切去至少三个弦, 形成至少三个爪 3 。后端面 34' 可以是与轴 线垂直的平面, 也可以是略向内倾斜而形成内锥状。 锁止片 3 ' 的外径 略大于针筒 1的内径尺寸, 推注药液时, 锁止片 3 ' 的爪 3 有圆弧倒 角的前端面被阻力环 14的后坡面 142挤压而发生弹性变形, 轻便地通 过阻力环 14, 而当注射完毕, 再向后抽动芯杆 2时, 锁止片 3 ' 的爪 31 ' 的后端面尖锐边缘与阻力环 14的前坡面 141根部接触, 爪 3 Γ 压 紧前坡面 141及针筒 1的内壁 15, 不能移动, 锁止片 3 '及活塞 4被阻 挡在针筒前端, 芯杆 2被拉脱, 造成失效, 从而实 了一次性使用的目 的。 The structure of another simpler locking piece 3 ′ is shown in FIG. 7. The locking piece 3 ′ is a sheet-shaped ring with a thick center and a thin edge, and is shaped like a hollow shallow disk. The front end face 33 'is a tapered surface, the rear end face 34' is a flat surface, and the outer edge of the front tapered surface 33 'is provided with a rounded chamfer. At least three strings are cut out of the outer circle of the locking piece 3 to form at least three claws 3. The rear end surface 34 'may be a plane perpendicular to the axis, or it may be slightly inclined inward to form an inner cone. The outer diameter of the locking piece 3 ′ is slightly larger than the inner diameter of the syringe 1. When the liquid is injected, the front end surface of the claw 3 of the locking piece 3 ′ is rounded and chased by the rear slope surface 142 of the resistance ring 14. The elastic deformation occurs, and the resistance ring 14 is passed lightly. When the core rod 2 is pulled backward when the injection is completed, the sharp edge of the rear end face of the claw 31 ′ of the locking piece 3 ′ and the root of the front slope surface 141 of the resistance ring 14 When contacted, the claw 3 Γ pressed the front slope surface 141 and the inner wall 15 of the syringe 1 and could not move. The locking piece 3 ′ and the piston 4 were blocked at the front end of the syringe, and the core rod 2 was pulled off, causing the failure and thus realized. Purpose of single use.
图 8 是本发明的自锁式注射器装配好之后、 使用之前的状态示意 图。此时锁止片 3或 3 '位于阻力环 14的后部, 自身安全限位卡板 131 已卡入芯杆的限位槽 25中, 由于活塞 4与孔壁 15的磨擦作用,防止了 卡板 131松动,卡板 131可阻止芯杆 2向前移动,从而防止了意外失效。 FIG. 8 is a schematic view of a state of the self-locking syringe of the present invention after assembly and before use. At this time, the locking piece 3 or 3 ′ is located at the rear of the resistance ring 14, and the self-limiting locking plate 131 has been locked into the limiting groove 25 of the core rod. The friction between the piston 4 and the hole wall 15 prevents the card from being stuck. The plate 131 is loose, and the clamping plate 131 can prevent the core rod 2 from moving forward, thereby preventing accidental failure.
图 9是使用该注射器抽取药液或血液示意图。回拉芯杆 2时活塞 4、 锁止片 3或 3 ' 均随之后移, 而在针筒 1内形成负压抽液状态, 限位槽 25的前斜面 251向上推动限位卡板 131离开芯杆 2的限位槽 25, 实现 了安全限位机构的自动解锁。连接卡板 131的塑料薄膜 133具有一定弹 性, 一旦卡板 131离开限位槽 25, 就不会落回原装配位置, 而处于图 9 所示的较高的位置。 当锁止片 3或 3 ' 拉到与针筒 1防脱环 16前坡面 接触时,将被阻挡而不可能再拉出,从而防止不经意时造成活塞抽出而 报废。 FIG. 9 is a schematic diagram of using the syringe to extract a medical solution or blood. When the core rod 2 is pulled back, the piston 4, the locking piece 3 or 3 'all move afterward, and a negative pressure pumping state is formed in the syringe 1. The front inclined surface 251 of the limiting groove 25 pushes the limiting card 131 upward to leave The limit slot 25 of the core rod 2 realizes the automatic unlocking of the safety limit mechanism. The plastic film 133 connected to the card board 131 has a certain elasticity. Once the card board 131 leaves the limiting slot 25, it will not fall back to the original assembly position, but is in a higher position as shown in FIG. When the locking piece 3 or 3 ′ is pulled into contact with the front slope surface of the syringe 1 prevention ring 16, it will be blocked and cannot be pulled out again, thereby preventing the piston from being pulled out and inadvertently scrapped.
图 10是注射操作完毕的示意图, 注射操作过程中, 如前所述, 自 身安全限位卡片 131 已弹离槽 25, 不会影响芯杆 2向前移动。 注射操 作完毕, 活塞 4到达针筒 1的顶端, 锁止片 3或 3 ' 已越过阻力环 14,
从而实现了一次性使用的自锁状态。 FIG. 10 is a schematic diagram of the injection operation. During the injection operation, as described above, the self-limiting card 131 has bounced away from the slot 25, and does not affect the forward movement of the core rod 2. After the injection operation is completed, the piston 4 reaches the top of the syringe 1, the locking piece 3 or 3 'has passed the resistance ring 14, Thus, a one-time self-locking state is achieved.
图 11是注射操作完毕后, 欲抽出活塞再次使用的状态。 回拉芯杆 2、 活塞 4及锁止片 3或 3 ' 向后移动, 当锁止片 3或 3 ' 端面与阻力环 14接触而被阻挡, 用力拉芯杆 2, 锁止片 3边缘向外扩张, 更贴紧针筒 1 内壁 15、 顶住阻力环 14, 而不能移动, 当拉力超出芯杆 2与活塞 4 间的分离力时, 芯杆 2的圆柱头 21从活塞 4中拔脱, 活塞 4与锁止片 3被锁在针筒 1的前端部空间, 而不能向后移动, 使注射器丧失基本功 能而失效, 实现了一次性的使用要求。 Fig. 11 shows a state where the piston is to be pulled out and used again after the injection operation is completed. Pull the core rod 2, the piston 4, and the locking piece 3 or 3 'back. When the end face of the locking piece 3 or 3' contacts the resistance ring 14, it is blocked. Pull the core rod 2 hard, and the edge of the locking piece 3 faces The outer expansion is closer to the inner wall 15 of the syringe 1 and the resistance ring 14 but cannot move. When the pulling force exceeds the separation force between the core rod 2 and the piston 4, the cylindrical head 21 of the core rod 2 is pulled out from the piston 4. The piston 4 and the locking piece 3 are locked in the space of the front end of the syringe 1 and cannot be moved backward, which causes the basic function of the syringe to be lost and fails, thereby realizing the one-time use requirement.
芯杆 2也可采用图 5的结构。 与图 4结构的主要区别在于芯杆 2 的前推板 23与十字筋板 24的水平或垂直板之间设置两个薄弱联结点 28, 如图 5所示, 薄弱联结点 28可以是两个小圆柱, 或其它便于生产 的形状。 与对比专利 CN97193570.X相比, 其最大特点是在相同的拉断 强度下,显著提高了芯杆薄弱断面的抗扭强度,对防止在生产和使用中 的意外断裂起到很好作用,提高了生产成品率和使用安全性,与此相应 的是芯杆 2与橡胶活塞 4配合的圆柱头 21尺寸与常规相同, 以保证高 的拉脱强度, 以使连接柱 28断裂时, 芯杆头部不与橡胶活塞分离。 图 12是采用该方案注射完成后, 芯杆 2再次回拉被拉断后的示意图。 注 射器使用后, 锁止片 3越过阻力环 14, 当回拉芯杆 2, 锁止片 3受到阻 力环 14的阻挡而不能移动,继续加力则芯杆 2薄弱连接柱 28断裂。芯 杆 2前部推板 23、 颈部 22、 头部 21及锁止片 3、 活塞 4被锁在针筒 1 前端,从而使注射器在使用一次后即丧失功能,成为真正意义上的一次 性使用注射器。 The core rod 2 may also adopt the structure of FIG. 5. The main difference from the structure of FIG. 4 is that two weak connection points 28 are provided between the front push plate 23 of the core rod 2 and the horizontal or vertical plate of the cross rib plate 24. As shown in FIG. 5, the weak connection points 28 may be two Small cylinders, or other shapes that are easy to produce. Compared with the comparative patent CN97193570.X, its biggest feature is that under the same tensile strength, the torsional strength of the weak section of the core rod is significantly improved, which plays a good role in preventing accidental fracture in production and use, and improves In order to ensure the production yield and the safety of use, the corresponding size of the cylindrical head 21 of the core rod 2 and the rubber piston 4 is the same as the conventional one to ensure high pull-out strength, so that when the connecting rod 28 is broken, the core rod head The part does not separate from the rubber piston. FIG. 12 is a schematic diagram after the core rod 2 is pulled back again and broken after the injection is completed in this scheme. After the injector is used, the locking piece 3 passes the resistance ring 14. When the core rod 2 is pulled back, the locking piece 3 is blocked by the resistance ring 14 and cannot be moved. When the force is continuously applied, the weak connecting rod 28 of the core rod 2 is broken. The front push plate 23, the neck 22, the head 21, the locking piece 3, and the piston 4 of the core rod 2 are locked at the front end of the syringe 1, so that the syringe will lose its function after one use and become a real one-time use. Use a syringe.
工业应用性 Industrial applicability
由上述可以看出, 本发明有如下优点: As can be seen from the above, the present invention has the following advantages:
1. 由于将具有锁止功能的部件独立于芯杆部件, 这给锁止片的设 计最优化创造条件, 模具简单, 组装容易, 成品率高, 能更好的满足制 造、 装配和使用要求。 1. Since the components with the locking function are independent of the core rod components, this creates conditions for the optimization of the design of the locking piece. The mold is simple, easy to assemble, and the yield is high, which can better meet the requirements of manufacturing, assembly and use.
2. 碟形锁止片的轴向瓣形结构, 使其在正向通过阻力环时变形量 很小, 推注阻力变化很小, 使注射器易于为使用者所接受, 而在反向拉
出时, 其瓣形支爪受到阻力环阻止时, 会更紧的压向针筒内壁, 因而能 产生足够大的阻力来防止锁止片被拉出。 此结构对小规格(0.5ml, lml 等) 注射器的适应性远优于现有上述对比专利结构。 2. The axial petal structure of the disc-shaped locking piece makes it small in deformation when it passes through the resistance ring in the forward direction, and the change in the bolus resistance is very small, which makes the syringe easy to be accepted by the user. When it is released, when its petal-shaped claw is blocked by the resistance ring, it will be pressed tighter towards the inner wall of the syringe, so it can generate enough resistance to prevent the locking piece from being pulled out. The adaptability of this structure to small-size (0.5ml, lml, etc.) syringes is much better than the existing comparative patent structure.
3. 本发明采用使芯杆与橡胶活塞拉脱分离方案, 不存在成品率下 降及使用中意外损坏问题, 降低了生产成本及使用风险。 3. The present invention adopts a separation and separation scheme for the core rod and the rubber piston, which does not have the problems of decreased yield and accidental damage during use, and reduces production costs and use risks.
4. 自身安全限位机构能有效防止在使用前注射器的意外失效。 其 独特的设计使其在常规注射操作时自动解锁, 无需增加任何附加操作, 这使该注射器使用与现有的普通注射器完全相同。 4. Its own safety limit mechanism can effectively prevent accidental failure of the syringe before use. Its unique design allows it to be automatically unlocked during routine injection operations without the need for any additional operations, which makes the syringe use exactly the same as existing ordinary syringes.
5. 由于所有零件与现有注射器结构相近, 制造难度相当, 锁止片 装配容易, 因而生产成本与现有普通注射器相当或略高,有利于本发明 的推广应用。
5. Since all parts are similar in structure to the existing syringe, the manufacturing difficulty is relatively equal, and the locking piece is easy to assemble, so the production cost is equivalent to or slightly higher than the existing ordinary syringe, which is beneficial to the popularization and application of the present invention.