Syringe for medical use

Abstract

A syringe for medical use having a barrel with a longitudinally extending tubular fluid chamber and at least one longitudinally extending, outwardly facing, substantially flat indicia display surface disposed proximate the fluid chamber, a plunger slidably inserted into the fluid chamber, a needle forwardly projecting from the barrel and in fluid communication with the fluid chamber, and a fixed length needle safety device having an actuation handle slidably engaged with the barrel and a needle tip shield forwardly projecting and encircling the needle, the needle tip shield moving forwardly to cover the tip of the needle when the actuation handle is moved forwardly after use of the syringe.

Description

[0001] This application is a divisional application of Chinese Patent Application No. 201980096896.9, filed on September 25, 2019, entitled "Injector with a flat marking display surface". Technical Field

[0002] This invention relates to a syringe configured for aspirating or injecting fluids for medical use. The syringe ideally includes a barrel, a piston slidably engaged with a portion of the barrel, and a forward-extending needle. The barrel ideally has a substantially tubular inner surface and a longitudinally extending and substantially flat marking display surface, wherein the inner surface serves as a sidewall of the fluid chamber, and the marking display surface is disposed on at least one side of the barrel. Preferably, the syringe of this subject includes two opposing, outward-facing, longitudinally extending, and substantially flat marking display surfaces adapted for printing dosage graduations on the syringe.

[0003] One embodiment of the invention further includes a needle retraction mechanism and a laterally biased needle retraction chamber that extends substantially along the length of the fluid chamber of the syringe. After injection, the needle is selectively retracted by laterally moving the needle retraction chamber to align it coaxially with the needle, by sliding the syringe and the needle retraction chamber laterally relative to the needle. Without increasing the overall length of the syringe, the substantially full-length, laterally biased needle retraction chamber facilitates the selective use of longer retractable needles compared to conventional safety syringes with retractable needles, and expands the range of applications and procedures performed with the device. Depending on the needle length, these applications and procedures may include, for example, spinal punctures, epidural anesthesia, cyst aspiration, and intradermal, subcutaneous, or intramuscular injections.

[0004] Another aspect of the invention relates to a syringe with a barrel comprising a generally cylindrical fluid chamber, a needle retraction cavity disposed parallel to and laterally spaced apart from the fluid chamber, and at least one generally flat, outward-facing display surface to which markings, such as dosage graduations, can be applied using conventional pad printing processes. Another aspect of the invention also relates to a syringe with a barrel having two opposing, generally flat surfaces on which the same or different markings can be pad printed without rotating the barrel, even on syringes of 1 mL, 0.5 mL, or smaller. The generally flat display surface also facilitates the application of markings to the syringe by other processes such as embossing, injection molding, etc.

[0005] Another aspect of the invention relates to a medical syringe comprising the barrel and piston disclosed above, and a front attachment having a forward-extending, rearward-biased needle. The front attachment and the barrel are ideally configured such that the front attachment slidably engages the front portion of the barrel along an axis transverse to the longitudinal axis passing through the needle.

[0006] Another embodiment of the invention described above with reference to paragraph 1 implements a needle safety device having a needle tip shield extending circumferentially around the needle and ideally coaxially aligned with the needle. The needle tip shield is ideally connected to or integrally molded with an elongated actuating handle, which is also part of the needle safety device and slidably engages the syringe barrel. The needle safety device of this embodiment eliminates the need for a needle retraction mechanism and a needle retraction cavity, and eliminates the need for lateral sliding movement of the syringe barrel relative to the needle, thereby protecting the user from accidental needle pricks. After using the syringe of this embodiment, the needle tip shield selectively advances to protect the user from injury by manually applying pressure to the touch surface of the actuating handle located behind the needle and the needle tip shield, thus protecting the user from injury by the forward-protruding needle tip. The actuating handle slidably engages the syringe barrel and can slide forward relative to the barrel from a first position to a second position, wherein in the first position the needle tip is not covered, and in the second position the needle tip is surrounded by the needle tip shield and protected from unintentional needle pricks. Because this embodiment of the forward-sliding needle safety device incorporates a stop surface that prevents subsequent rearward movement of the device relative to the syringe barrel, it protects the user from subsequent accidental exposure of the needle tip and associated needlestick injuries. This embodiment of the invention combines the advantages of a flat, printable surface with more legible dosage markings with the cost advantages of a simpler yet still effective and easy-to-use needle safety device to provide a safer and more affordable solution, particularly for those requiring frequent injections to treat various chronic conditions. Furthermore, because the dosage markings and markings are easier for the user to read, the risk of administering incorrect doses of pharmaceutical fluid to the patient is reduced, thereby minimizing the risk of other unintended consequences. Background Technology

[0007] Syringes intended for medical use typically have a barrel comprising a generally cylindrical inner and outer wall, meaning that volumetric dosage markings or other markings are applied to the arched outer surface during manufacturing. This can be challenging, especially when the barrel diameter and the radius of curvature of the outer wall are small (e.g., 1 mL, 0.5 mL, and smaller syringes), and when the available outer surface area is extremely limited, or on syringes with different dosage scales or other markings applied to opposite sides of the barrel. In such cases, it is often necessary to rotate or turn the barrel during printing, and it is also often difficult to read markings and related values ​​or other markings, such as dosage measurement lines, because of their extent around the circumference of the barrel, and because markings or markings on one side are often visible through the syringe and can confuse the user, sometimes even leading to medical accidents. For at least these reasons, syringes with a generally flat surface for applying dosage markings and other markings are required.

[0008] Medical syringes with a rearwardly biased needle retracting into a coaxially aligned retraction chamber disposed within a piston are known. Such medical syringes have been previously disclosed, for example, in U.S. Patent Nos. 5,049,133, 5,053,010, 5,084,018, and 6,090,077. More recently, for example, US 9,381,309 discloses a medical syringe with a fore-end accessory comprising a rearwardly biased needle retracting into a needle retraction chamber that is part of the fore-end accessory.

[0009] Recently, a medical syringe with a front attachment has also been disclosed, which slidably engages with a barrel having a needle retraction cavity integrally molded with the barrel and arranged parallel to the fluid chamber. In US9,814,841 (Figures 37 to 42), for example, the length of the needle retraction cavity is significantly shorter than the length of the fluid chamber within the barrel, and the needle retraction cavity does not cooperate with the outer wall of the barrel but forms a substantially flat outer surface adjacent to and substantially co-extending with the fluid chamber.

[0010] Other references disclosing devices that may have some degree of similarity to various aspects or embodiments of the present invention include the following: US4,573,976, US4,702,738, US4,790,828, US4,915,696, US5,037,402, US5,092,461, US5,215,534, US5,312,372, US9,623,192; US Publication No. 2002 / 0065488A1, US Publication No. 2003 / 0038171A1, and US Publication No. 2005 / 0159706A1. Summary of the Invention

[0011] According to one embodiment of the invention, a syringe for medical use is disclosed, comprising a one-piece barrel having a fluid chamber and a laterally biased needle retraction cavity, the fluid chamber and the needle retraction cavity being substantially parallel and spaced apart by a common wall. The needle retraction cavity may have a non-circular cross-section and ideally extend substantially co-linearly with the fluid chamber in length, thereby facilitating the use of longer needles without increasing the overall length of the barrel to accommodate the retraction of longer needles, as is the case with a safety syringe where the needle is retracted into the barrel after use. The barrel also includes an outer wall having at least one substantially flat, outward-facing display surface on which markings such as volumetric dosage scales can be applied using conventional pad printing techniques or other similar efficient alternatives. The at least one substantially flat display surface is ideally located close to the fluid chamber and ideally includes measuring graduations at least longitudinally aligned with the portion of the fluid chamber used for injection or aspiration of fluid. According to a preferred embodiment of the invention, two opposing, longitudinally co-existing, substantially flat surfaces are provided, each surface spanning at least a portion of the outer wall of the fluid chamber and at least a portion of the outer wall of the needle retraction cavity.

[0012] This invention is particularly applicable to syringes with a usable volume of 1 mL or less, which typically have a small barrel diameter, causing the volumetric dosage markings applied to the outer surface to surround a large portion of the barrel's axial direction. According to another preferred embodiment of the invention, the volumetric dosage markings or other markings are applied to a substantially flat display surface of the syringe using pad printing (sometimes referred to as "letterpress printing"). The needle retraction cavity can be formed (preferably molded from a suitable polymer material) with a non-circular cross-section and laterally offset relative to the barrel to facilitate the creation of a wider, outward-facing, substantially flat display surface during manufacturing. The substantially flat display surface ideally includes at least one side of the fluid chamber near the barrel, and, if desired, the volumetric dosage markings or other markings can be molded onto other flat display surfaces, or imprinted onto or into the display surface.

[0013] Another embodiment of the syringe of this subject includes a barrel and a piston as disclosed above, and includes a front attachment having a forward-extending, rearward-biased needle. The front attachment and barrel are ideally configured such that the front attachment slidably engages the front portion of the barrel along an axis transverse to the longitudinal axis passing through the needle. When the syringe is positioned in the use position, the needle is aligned with a first opening in the front portion of the barrel, which communicates with a generally cylindrical fluid chamber within the barrel to establish a coaxially aligned fluid flow path between the fluid chamber and the needle. A fluid seal is ideally located around the first opening to prevent fluid leakage between the front attachment and the barrel. A needle retraction chamber extends rearward from a second opening in the front portion of the barrel and is parallel to and spaced from the fluid chamber within the barrel, and ideally shares a common wall with at least a portion of the fluid chamber. After the syringe is used, the relative lateral movement between the barrel and the front accessory repositions the rearward-biased needle to align with the needle retraction chamber, thereby releasing the needle and forcing it into the retracted position by the biasing device (usually a compression spring), in which the needle no longer extends forward from the syringe.

[0014] Another embodiment of the syringe of this subject matter is implemented as a medical syringe having a wider, substantially flat display surface, the syringe having an integral barrel and needle retraction cavity, which cooperate with the substantially flat edge portion of the surrounding flange to help prevent the syringe from rolling off a tray or other flat surface. The substantially flat surface also allows for a suitably narrower flange around the barrel, but still provides a larger surface area, making it easier for the user to grip. The opposing, substantially flat surfaces also improve stability and the user's control over the syringe during injection or other procedures. Because the syringe of this subject matter has a barrel with a laterally biased needle retraction cavity, and the needle retraction cavity can be integrally molded with the fluid chamber, at least one, preferably two (opposite facing) substantially flat and outward-facing surface areas are provided for arranging an arrangement including volume scales or other markings that are easily readable by the user, thereby reducing the likelihood of dosage errors during aspiration or injection.

[0015] Another embodiment of the invention includes a syringe of the subject matter coupled with a selectively releasable needle cap, the needle cap further comprising a locking member configured to engage a portion of the barrel and prevent lateral sliding of the barrel relative to a front attachment to prevent accidental needle retraction before use of the syringe. Retracting the needle after use reduces the likelihood of repeated syringe use or accidental needle pricks and reduces the unintentional spread of blood-borne pathogens.

[0016] Another embodiment of the invention includes a syringe of the subject matter in conjunction with a piston cap, the piston cap being releasably attached to the rear portion of the syringe, typically behind the finger-like flange, and selectively removable before aspirating fluid or use. When both the needle cap and piston cap are in place, the needle and internal fluid-contact portions of the syringe are sealed and protected from contamination, regardless of whether the syringe is also enclosed in another package. Therefore, the syringe can be assembled and transported in bulk before packaging and sterilization.

[0017] While the syringes of this subject are particularly suitable for administering relatively small doses of pharmaceutical fluids, such as insulin or vaccines, to a user by injection or infusion, the construction and operation of the device are not limited to a specific size, dosage, or procedure. For example, syringes constructed as disclosed herein can also be configured for aspirating fluid samples from a patient during clinical procedures such as knee or spinal punctures. Because the overall length of the syringe is reduced by combining the disclosed front attachment with the novel barrel of the present invention, a longer needle can be used, and the needle can still retract into the syringe after use. As used herein, “retracted” or “retracted” refers to the process of moving the needle from a forward-extended use position to a post-use position, in which the needle tip no longer extends forward from the front attachment, regardless of whether the force acting on the needle tip is pushing or pulling the needle tip backward from the forward-extended position.

[0018] Another embodiment of a syringe for medical use is disclosed, the syringe comprising: a barrel having a longitudinally extending tubular fluid chamber and at least one longitudinally extending, outward-facing, substantially flat marking display surface disposed near the fluid chamber; a piston slidably inserted into the fluid chamber; a needle extending forward from the barrel and in fluid communication with the fluid chamber; and a needle safety device fixed and having a predetermined length. The needle safety device ideally includes an actuating handle slidably engaged with the barrel and a forward-extending needle tip shield surrounding the needle. In a first stop position, the needle tip shield is disposed around the nose portion of the barrel. In a second stop position, after use of the syringe, the actuating handle moves forward under manual pressure, causing the needle tip shield to move forward to circumferentially surround and cover the tip of the needle.

[0019] Another embodiment of the invention is disclosed, which ideally implements one, and preferably two, opposing, substantially flat marking display surfaces, and also implements a needle safety device with a tip guard extending circumferentially around the needle and ideally coaxially aligned with the needle. The tip guard is attached to or connected to an actuating handle slidably engaged with the barrel, or integrally molded with the actuating handle. Suitable guides, ramps, stop shoulders, and locking pins, or other similar effective devices, are ideally configured as part of the needle safety device and the barrel, such that the actuating handle can advance smoothly and substantially without interference when needed, and that the actuating handle will not subsequently retract accidentally, exposing the needle tip. The needle safety device of this embodiment of the invention eliminates the need for a needle retraction mechanism, a needle retraction cavity, or any lateral sliding of the barrel relative to the needle to protect the user from accidental needle pricks. After use of the syringe, by manually applying pressure to the touch surface of the actuation handle located behind the needle and tip guard, the tip guard selectively advances to protect the user from injury by the forward-protruding needle tip. The actuation handle slidably engages the syringe barrel and can slide forward relative to the barrel from a first position to a second position. In the first position, the needle tip is not covered; in the second position, the needle tip is surrounded by the tip guard and protected from accidental needle pricks. When the needle safety device is fully extended relative to the barrel, the needle tip is ideally fully contained within the tip guard, so that a person handling the used syringe will not be accidentally pricked by simply placing their fingertip on the end of the syringe.

[0020] In another embodiment of the invention, the actuation handle further includes a touch surface that can be manually engaged.

[0021] In another embodiment of the invention, the barrel and the actuation handle include cooperatively engaging elements such that a manually actuated, controlled, and longitudinally sliding movement of the actuation handle relative to the barrel occurs between two predetermined stop positions. The first stop position is a fully retracted use position, in which the needle tip shield substantially surrounds the nose. The second stop position is a fully extended post-use position, in which the needle tip shield circumferentially surrounds the tip of the forward-extending needle.

[0022] In a preferred embodiment of the invention, the forward-extending needle is configured to be fixed relative to the nose of the barrel; however, it should be understood while reading this disclosure that a syringe with a similar configuration can be made with a needle configured to be selectively attached to the barrel.

[0023] These and other features of the invention will be better understood by taking into account the following detailed description of various embodiments and the appended claims in conjunction with the accompanying drawings. Attached Figure Description

[0024] The syringe of the present invention will be further described and illustrated with reference to the following accompanying drawings, in which:

[0025] Figure 1 This is a front top perspective view of one embodiment of the invention, wherein a needle cap (including a locking member) and a piston end cap are installed in a position where the syringe of the present invention can be packaged, transported and stored, wherein the locking member of the needle cap restricts lateral sliding movement of the barrel relative to the front attachment before use;

[0026] Figure 2 yes Figure 1 A front-top perspective view of the embodiment, in which the needle cap has been removed;

[0027] Figure 3 yes Figure 1 A disassembled front-top perspective view of the implementation method;

[0028] Figure 4 yes Figure 2 The right front view of the implementation method;

[0029] Figure 5 It is along Figure 4 The cross-sectional view taken from line 5-5;

[0030] Figure 6 Is with Figure 3 The front portion of the cylinder in the embodiment is shown side by side. Figure 3 A detailed perspective view showing the partial disconnection of the front attachment in the embodiment.

[0031] Figure 7 yes Figure 3 Rear top perspective view of the front attachment;

[0032] Figure 8 yes Figure 4 The right front view of the embodiment, wherein the piston cap is removed and the piston is retracted to the suction position;

[0033] Figure 9 It is along Figure 8 A cross-sectional view taken from line 9-9;

[0034] Figure 10 yes Figure 8 The right front view of the embodiment, wherein the needle is retracted and the piston is fully advanced inside the cylinder;

[0035] Figure 11 It is along Figure 10 A cross-sectional view taken from line 11-11;

[0036] Figure 12 yes Figure 2 Front view of the implementation method;

[0037] Figure 13 yes Figure 12 The front view of the embodiment shows the front attachment repositioned relative to the barrel, and the needle retracted to... Figure 10 and Figure 11 The location shown;

[0038] Figure 14 This is a front top perspective view of another embodiment of the syringe of the present invention, wherein both the needle cap and the piston cap are shown in their positions when the syringe is first removed from its packaging;

[0039] Figure 15 Is it like this? Figure 14 The syringe of the embodiment shown has both the needle cap and the piston cap removed;

[0040] Figure 16 Is it like this? Figure 15 The syringe of the illustrated embodiment, wherein the needle safety device moves forward relative to the barrel and the needle, and the needle tip shield surrounds and covers the needle tip;

[0041] Figure 17 yes Figure 14 A top perspective view showing the disassembled syringe of the embodiment;

[0042] Figure 18 yes Figure 14 A side front view of the syringe according to the embodiment;

[0043] Figure 19 yes Figure 14 A top plan view of the syringe according to the embodiment;

[0044] Figure 20 It is along Figure 19 A cross-sectional view taken from line 2-2;

[0045] Figure 21 Is it like this? Figure 15 The front view of the syringe of the illustrated embodiment rotated 180° about the longitudinal axis from opposite sides;

[0046] Figure 22 Is it like this? Figure 16 Side front view of the syringe of the embodiment shown;

[0047] Figure 23 Is along such Figure 22 A side front view of a cross-section taken along the longitudinal axis of the needle of the syringe of the illustrated embodiment; and

[0048] Figure 24 Is it like this? Figure 18 The syringe of the illustrated embodiment is shown in a bottom plan view.

[0049] It should be noted that the accompanying drawings are not necessarily drawn to scale. Detailed Implementation

[0050] refer to Figure 1 The syringe 20 includes a barrel 22, which further includes a substantially flat display surface 23, a front attachment 24, and an outer wall 25 of the fluid chamber 75. Figure 9 (See image) The arrangement of the selectively removable needle cap 26, volume measurement marks 27, finger flange 28, removable piston cap 30, and locking member 40. (See image) Figure 1 As shown, the primary volume measurement markings 27 are applied to the display surface 23, and may include, for example, at least Arabic numerals identifying the number of fluid units and associated primary measurement markings. However, it should be understood that the figures in the accompanying drawings are for illustrative purposes and not drawn to scale, and the positions of some features such as the auxiliary unit markings 27 relative to the substantially flat display surface 23 may differ from those shown. Ideally, at least a portion of each auxiliary (individual) unit marking or notation begins on or near the edge of the display surface 23 and selectively continues a short distance along the curved outer wall of the fluid chamber 25. This positioning is understood to be within the operational capabilities of conventional pad printing techniques readily available to those skilled in the art.

[0051] like Figure 1 As shown, the syringe 20 has a front attachment 24 shown in a "pre-use" configuration, with the needle cap 26 and locking member 40 in place to prevent the front attachment 24 from moving laterally relative to the barrel 22 before use due to unintentional pressure applied to the textured touchpad 46 or to the opposite side of the barrel 22. A removable piston cap 30 is also mounted behind the finger flange 28 to prevent the piston (not visible) from being accidentally withdrawn from the barrel 22 and to prevent unintentional contamination within the rear opening of the barrel 22 or around the rearwardly extending handle portion of the piston, such as... Figure 9 As shown, this will be discussed below.

[0052] Reference Figure 2 , Figures 4 to 5 and Figure 12 Except for the removal of the needle cap 26 (with locking member 40), the syringe barrel 22 and the front accessory 24 are in contact with... Figure 1 At the same location. The front opening leading to the needle retraction chamber 92 is more clearly visible, and the needle 34 is also visible, extending forward from the needle support member 32 of the front accessory 24. Around the needle support member 32 are circumferentially spaced and axially tapering ribs 33, which provide a surface for frictional engagement with the inner surface of the needle cap 26 before removal of the needle cap. Figure 2 In the middle, the needle 34 ideally passes through the fluid chamber 75 ( Figure 9 The longitudinal axis of the ) is aligned coaxially.

[0053] Reference Figure 3 The needle cap 26 of the syringe 20 further includes a forward-facing, inwardly tapering, generally cylindrical sidewall with a front end 36, a rearward-facing annular clamp 38, and a locking member 40 extending rearward beyond the annular clamp 38. The front attachment 24 further includes a forward-extending, generally tubular needle support member 32, an upper guide member 44, and a lower guide member 45 (in...). Figure 7 (See in the center) and a textured touchpad 46 extending laterally, wherein the needle support member has a front opening 42.

[0054] The syringe 20 ideally includes a needle 34 with a forward-angled needle tip 48, and also includes a needle retraction mechanism, which further includes a helical compression spring 50 and a needle retainer 52. The needle retainer 52 further includes an elongated shaft 54 ​​with a tubular orifice 58, which can be inserted into the rear portion of the spring 50. The diameter of the head 56 of the needle retainer 52 is sufficiently larger than the inner diameter of the spring 50 such that when the front accessory 24 is slidably engaged with the front portion 64 of the barrel 22, the spring 50 can be held in a compressed state by the head 56, as described below. Figure 6 and Figure 7 The rear end of the needle 34 can be inserted into the tubular hole 58 of the needle holder 52 and can be securely attached to the interior of the elongated shaft 54 ​​by any suitable, commercially available means (e.g., adhesive). Although the needle retraction mechanism disclosed herein is applicable to the syringe 20, it should be understood that other similar effective elements and mechanisms for rearward biasing of the needle 34 within the syringe 20 can also be used in the manufacture of this invention.

[0055] Still referencing Figure 3 An annular polymer fluid seal 60, having a tubular orifice 62, is ideally inserted into a recess 66 located in the front portion 64 of the barrel 22, such that when the needle retraction mechanism is mounted within the front attachment 24 and the front attachment 24 is slidably engaged with the front portion 64 of the barrel 22, the forward-facing end of the seal 60 is positioned to abut against the rearward-facing head 56 of the needle holder 52. When the front attachment 24 of the syringe 20 is assembled to the front portion 64 of the barrel 22 during manufacturing, a continuous, substantially linear fluid flow path is established through the needle 34, the needle holder 52, and the annular fluid seal 60 to the tubular, longitudinally extending fluid chamber 75 (in...). Figure 9 (See in the middle).

[0056] In addition to the front portion 64, the barrel 22 also includes a substantially flat display surface 23, a curved outer wall surface 25, a finger-shaped flange 28, and a rearwardly extending annular clamp 70. During the assembly of the syringe 20, the elastomeric piston seal 76 is ideally mounted on a forward-extending boss 74 located on the front end of the piston handle 72 opposite the rearward-facing piston thumb pad 78, and then the piston handle 72 is inserted into the rearward-facing opening defined by the annular clamp 70. The assembly of the syringe 20 is then completed by mounting a substantially cylindrical piston cap 30 on the rearward-facing end of the barrel 22. The piston cap 30 also includes an open front end 80, a cylindrical bore 82, and a closed rear end 84. The piston cap 30 is mounted around the piston thumb pad 78 and frictionally engages with the outer wall of the annular clamp 70. (See below for details.) Figure 1 The volume measurement markings 27, as discussed, also appear on the outward-facing portions of the substantially flat display surface 23 and the curved outer wall surface 25.

[0057] Figure 3 , Figure 6 and Figure 11 A forward-facing opening is also disclosed, leading to a needle retraction cavity 92 associated with the front portion 64 of the barrel 22. The needle retraction cavity 92 has a closed rear end adjacent to the finger flange 28, and is defined by side walls 90, 95, a bottom wall 94, and a top wall, the top wall also including an upward-facing, substantially flat display surface 23 of the barrel 22.

[0058] Reference Figure 6 and Figure 7 Further description and explanation of the assembly of the front accessory 24 with the front portion 64 of the syringe barrel 22. (Refer to...) Figure 6 First, place the annular fluid seal 60 (in Figure 3 (As can be seen) inserted into the recess 66 of the front portion 64 of the cylinder 22. The front portion 64 further includes a laterally extending top guide 68 and a bottom guide 69, which are positioned relative to the fluid chamber 75 passing through the cylinder 22. Figure 9 The longitudinal axis of the tube is arranged laterally. Rounded attachment guides 96 and 98 are respectively provided at the front of the top guide rail 68 and the bottom guide rail 69, and are configured to facilitate the assembly of the front attachment 24 to the front portion 64 of the tube 22 by moving upwards at the upper and lower parts of the arm that connects the textured touch panel 46 to the back side of the front attachment 24.

[0059] Reference Figure 7 An annular opening 112 is provided in the back side of the front accessory 24 to facilitate the insertion of the spring 50 and the needle holder 52, as described above. Figure 3As discussed, and when the front attachment 24 moves to slide engagement with the front portion 64 of the cylinder 22, the spring 50 is ideally compressed in the front opening 42 (in Figure 11 The annular shoulder portion (visible in the center) is between the needle holder 52 head 56 and the rear portion is compressed by the needle holder 52 head 56. The front attachment 24 also includes an upper guide portion 44 and a lower guide portion 45, the upper guide portion having a downward-facing and laterally extending recess 100, and the lower guide portion having an upward-facing and laterally extending recess 102. The upper ramp portion 104 and the lower ramp portion 106 of the front attachment 24 are configured to slide on two laterally spaced opposing ramp portions respectively (the lower set is on...). Figure 6 (Not visible in the middle), wherein the sloping part has blocking shoulders 77, 79. The front part attachment 24 and the front part 64 are as follows Figure 6 During positioning, by sliding the front attachment 24 onto the front portion 64 of the barrel 22, the laterally extending top guide rail 68 and bottom guide rail 69 of the front portion 64 of the barrel 22 ideally engage cooperatively with the upper recess 100 and lower recess 102, respectively. When pressure is applied to the textured touch surface 46, the front attachment 24 moves along the guide rails 68, 69 until the top and bottom blocking shoulders 108 of the upper guide 44 pass the upper and lower blocking shoulders, and then descends to face the upper and lower blocking shoulders 77. At this time, the needle support member 32 and the needle holder 52 (in Figure 6 and Figure 7 (Not shown in the image) Ideally, it corresponds to the fluid chamber 75 ( Figure 9 The longitudinal axis (as seen in the image) is coaxially aligned. Any movement of the front attachment 24 back to its original position... Figure 6 Attempts to disconnect the indicated position will be hindered by the facing and adjacent contact between the upper and lower blocking shoulders 77 of the front portion 64 and the top and bottom blocking shoulders 108 and 110 of the front attachment 24, respectively.

[0060] Figure 4 and Figure 5 It shows Figure 2 The syringe 20 has its needle cap removed and piston cap 30 still in place, and as described above, the textured touch surface 46 is in its initial position relative to the barrel 22. The needle 34 is mounted within the hole 58 of the needle holder 52, which is located within the needle support member 32 of the front accessory 24, wherein the spring 50 is compressed in the head 56 of the needle holder 52. Figure 3Between. Spring 50 applies a backward biasing force to needle holder 52 and needle 34, and needle holder faces the front surface of annular fluid seal 60 and is pressed by spring 50 into abutment contact with the front surface of annular fluid seal, thereby establishing a fluid chamber 75 (in) leading to cylinder 22 through needle 34, needle holder 52 and fluid seal 60. Figure 9 The fluid path is coaxially aligned (as can be seen in the image). Figure 4 and Figure 5 As shown, the piston seal 76 is pushed fully forward into the generally cylindrical fluid chamber 75 of the cylinder 22.

[0061] Reference Figures 8 to 9 The syringe 20 is configured such that fluid can be drawn into the syringe, while the textured touchpad 46 remains in the same initial position as described above. The piston cap 30 (as in...) Figure 2 , Figures 4 to 5 (As shown) is removed, and piston handle 72 is retracted, just as it would be when fluid is drawn into fluid chamber 75. Figure 9 As can be seen, the needle retraction chamber 92 extends substantially along the same length as the fluid chamber 75, thereby facilitating the placement of the volume measurement mark 27 on the substantially flat surface 23. Figure 3 (As can be seen in the image), this helps to fully utilize the volume of the fluid chamber 75 and also facilitates needle retraction, such as with biopsy needles that are typically much longer than needle 34 (as seen in the image below). Figure 11 (Visible within the needle retraction chamber 92). Fluid can also be injected into the patient or expelled from the fluid chamber 75 by applying finger pressure against the forward-facing side of the flange 28 while the piston thumb pad 78 is being pressed forward.

[0062] Reference Figures 10 to 11 and Figure 13 The piston handle 72 and piston seal 76 have been pushed forward to empty the fluid chamber 75. To retract the needle, pressure is applied to the textured touchpad 46, which moves the front attachment to a position where the needle support member 32 is aligned with the needle retraction chamber 92. Because the needle retraction chamber 92 has a larger front opening than the head 56 of the repositioned needle holder 52, the biasing force of the compressed spring 52 pushes the needle holder 52 backward, advancing the needle holder 52 and the needle 34 into the distal end of the needle retraction chamber 92.

[0063] Refer again Figure 6 and Figure 7 A force is applied further to the textured touch surface 46 of the forward attachment 24 relative to the cylinder 22, as described above. Figures 10 to 11As described, a sliding relative movement occurs between the front attachment 24 and the front portion 64 of the cylinder 22. This movement causes the upper ramp portion 104 and the lower ramp portion 106 to slide on two sets of opposing ramp portions and blocking shoulders 79, such that the top blocking shoulder 108 and the bottom blocking shoulder 110 are positioned facing and adjacent to the upper blocking shoulder and the lower blocking shoulder 79, thereby preventing the front attachment 24 from returning to the use position relative to the cylinder 22.

[0064] Overall reference Figures 14 to 24 And specifically refer to Figures 14 to 17 Another embodiment of the invention is disclosed, comprising a syringe 200, which further includes a barrel 210, a needle safety device 212, a needle cap 214, and a piston cap 216. The barrel 210 ideally includes at least one longitudinally extending, substantially flat marking display surface 220, which displays easily readable volume graduations. In a preferred embodiment of the invention, the barrel 210 includes two opposing, substantially flat marking display surfaces 220 and 236. Figure 16 ). When the needle cap 214 and piston cap 216 are attached... Figure 14 After being removed from the device, the forward-extending needle 225 and the rearward-extending piston 224... Figure 15 The needle 225 becomes visible. The needle 225 is coaxially aligned with the piston 224, and the needle is positioned relative to the nose 234. Figure 16 , Figure 17 , Figure 20 The narrow orifice 250 within the tube remains fixed, with the nose located at the front end of the tube body 210. (Alternatively, it should be understood that the needle 225 and the nose 234 may be cooperatively configured such that the needle 225 can be releasably attached to the nose 234 if needed, to allow the use of needles of different sizes with the tube body 234.)

[0065] The orifice 250 allows the needle 225 to be in fluid communication with a fluid reservoir located within the tubular body 258, between the nose 234 and the piston seal 260 located at the front end of the piston handle 240. Before injection ( Figure 20 ) or after injection ( Figure 23 When the piston handle 240 is fully pushed forward against the rear of the nose 234 of the barrel 210, the fluid chamber is not visible. When the syringe 200 is ready to inject, as discussed below, when fluid is drawn into the syringe 200, the fluid reservoir is the space within the tubular section 258 located between the rear of the nose 234 and the front of the piston seal 260 (not visible in these views).

[0066] Reference Figure 17The needle safety device 212 also includes an actuation handle 228 and a needle tip shield 232. The actuation handle 228 further includes a rear end 268, a touchpad 226, and a pair of longitudinally extending channels 227 disposed on opposite sides of the actuation handle 228. The function of the channels 227 will be discussed below in conjunction with the sliding engagement of the barrel 210. The needle tip shield 232 further includes an inner bore 248 coaxially aligned with the nose 234 of the needle 225 and the barrel 210. Ideally, the needle tip shield 232 has an inner diameter that will allow the needle tip shield 232 to be in a position where... Figure 15 , Figure 21 The position shown is such that it slides on the nose 234 and is coaxially aligned around the nose, and the needle tip shield 232 is long enough to... Figure 16 , Figures 22 to 23 As shown, it securely covers the tip of needle 225 when moved forward. A slight frictional engagement may be provided between the inner wall of the needle tip guard 232 and the nose 234 to help maintain the needle safety device 212 in a stable axial position relative to the barrel 210 during use of the syringe 200. Ideally, the needle safety device 212 is integrally molded from a polymeric material, and its dimensions and construction can be cooperatively designed to slidably engage with the barrel 210, while also taking into account the range of needle lengths used in the syringe 200.

[0067] Refer again Figure 17 The cylinder 210 also includes a nose 234 coaxially aligned with the inner bore 250 and a tubular section 258 extending rearward from the nose 234 to a finger-shaped flange 218. The rear end of the tubular section 258 is open and communicates with the interior of a cylindrical, rearwardly extending clamp 230, to which a piston cap 216 is releasably attached. Relative markings indicate surfaces 220 and 236. Figure 16 Ideally, the printable surfaces are parallel, longitudinally extending, and substantially flat, each with opposing volume scales including appropriate markings near the tubular section 258 to facilitate easy reading of the fluid level within the tubular section 258 by the user. Ideally, longitudinally extending guides 256 with inwardly projecting retainer edges 254 are provided on the inward-facing walls of each outward-facing marking display surface 220, 236. The dimensions and construction of the longitudinally extending guides 256 are cooperatively configured to engage each alignment channel 227 of the needle safety device 212 and provide a smooth and slidable interface along each alignment channel of the needle safety device. The barrel 210 is ideally molded from a medical-grade polymer material and is transparent enough to allow the user to clearly see the fluid level drawn into the tubular section 258 of the syringe 200. (Referring to...) Figure 17The piston 224 also includes a thumb cap 238, a piston handle 240, a piston sealing retainer body 266, and an annular recess 264.

[0068] Reference Figures 15 to 17 , Figure 20 , Figures 22 to 23 The structural elements and operation of the needle safety device 212, which are cooperatively configured relative to the barrel 210 of the syringe 200, are further described and explained. During the assembly of the syringe 200, the actuating handle 228 of the needle safety device 212 is aligned with and inserted into the tubular section 258 of the barrel 210, wherein the guide rail 256 engages with the channel 227. The needle safety device 212 moves rearward relative to the barrel 210 until the needle tip shield 232 surrounds the nose 234 of the barrel 210, and the rear end 268 of the needle safety device 212 frictionally engages with the opposing rear stop 246. Each sliding stop 242 has a ramp 244 and a stop shoulder 252, and these sliding stops are positioned behind the guide rail 256 and in front of the rear stop 246. The opposing and facing ramp 244 allows the actuating handle 228 to slide forward relative to the barrel 210 to a position where the needle tip shield 232 covers and protects the tip of the needle 225 after the syringe 210 has been used. After the tip of the needle 225 is covered, the opposing and facing stop shoulder 252 prevents the actuating handle 228 from moving backward relative to the barrel 210 and exposing the needle tip again.

[0069] When the needle safety device 212 and the needle tip guard 232 are positioned relative to the cylinder 210 and the needle 225 as follows: Figure 15 , Figures 20 to 21 In the indicated position (referred to as the "first stop position"), the needle tip guard 232 surrounds a portion of the nose 234 of the syringe barrel and the needle 225. When the needle safety device 212 of the syringe 200 is in the first stop position, the tip of the needle 225 can pass through the stopper of a vial (e.g., an insulin vial), and by pulling back the piston 224, which is slidably engaged with the inner wall of the tubular section 258, medication can be drawn into the tubular portion 258 of the syringe barrel 210. Figure 17 , Figure 20 In the fluid storage section within ).

[0070] After injection or other use of the syringe 200, the needle safety device 212 is selectively moved forward. Figure 16 , Figures 22 to 23As shown in the "second stop position," syringe 200 can be reconfigured to a "safe" position where the needle tip is covered and protected to prevent accidental contact with healthcare professionals or patients. When syringe 200 is configured in the second stop position with needle safety device 212, the forward tip of needle 225 is circumferentially surrounded by needle tip guard 232, and (as shown in the image) Figure 16 and Figure 23 As shown, the front end of the needle tip shield 232 extends forward sufficiently beyond the tip of the needle 225 so that if the front end of the syringe 200 is pressed against a person's skin, he or she will not suffer an unintentional needle prick.

[0071] It is obvious that, after reading this specification in conjunction with the accompanying drawings, those skilled in the art can make various other modifications and changes to the embodiments disclosed herein, and the scope of the invention is intended to be limited only by the widest interpretation of the appended claims that the inventor is legally entitled to.

Claims

1. A syringe for medical use, comprising: A cylindrical body comprising a fluid chamber having a longitudinally extending tubular sidewall, a nose portion disposed in front of the fluid chamber, a rearwardly facing opening, and two opposing, substantially flat, parallel marking display surfaces extending longitudinally along the tubular sidewall and fixedly disposed relative to the fluid chamber, each marking display surface comprising a longitudinally extending guide rail and a volumetric dose scale mark, the longitudinally extending guide rail extending inward from an inwardly facing wall, and the volumetric dose scale mark disposed on an outwardly facing wall to facilitate reading the liquid level within the fluid chamber through at least a portion of the tubular sidewall; A piston that can be slidably inserted into the fluid chamber through the rearward-facing opening; A needle that extends forward from the nose and is in fluid communication with the fluid chamber; as well as A needle safety device, comprising a needle tip shield, an actuating handle disposed behind the needle tip shield, and longitudinally extending channels disposed on each side of the actuating handle; The dimensions and construction of the longitudinally extending channel are cooperatively designed to engage with the longitudinally extending guide of the marking display surface and provide a slidable interface to allow the needle safety device to slide between a first stop position and a second stop position relative to the barrel. Wherein, when the needle safety device is in the first stop position, the needle tip shield is at least partially disposed around at least a portion of the nose portion of the barrel; and When the needle safety device moves forward from the first stop position to the second stop position, the needle tip shield protects at least a portion of the front tip of the needle.

2. The syringe according to claim 1, wherein, Each of the longitudinally extending guides on the marking display surface includes an inwardly extending retainer edge.

3. The syringe according to claim 2, wherein, The dimensions and construction of the longitudinally extending channel are cooperatively designed to engage with the inwardly extending retainer edge of the longitudinally extending guide of the marking display surface and provide a sliding interface.

4. The syringe according to claim 3, wherein, The needle safety device is prevented from moving backward from the second stop position by at least one sliding stop adjacent to the rear end of the needle safety device, wherein the at least one sliding stop is disposed behind the longitudinally extending guide rail.

5. The syringe according to claim 1, wherein, The volumetric dosage scale markings are applied to the outward-facing wall of the marking display surface by at least one of a set of application methods, wherein the set of application methods includes molding, stamping, embossing, or printing.

6. The syringe according to claim 5, wherein, The volumetric dosage scale markings are applied to the marking display surface by pad printing.

7. The syringe according to any one of claims 2 to 4, wherein, The volumetric dosage scale markings are applied to the outward-facing wall of the marking display surface by at least one of a set of application methods, wherein the set of application methods includes molding, stamping, embossing, or printing.

8. The syringe according to claim 7, wherein, The volumetric dosage scale markings are applied to the marking display surface by pad printing.

9. The syringe according to claim 1, wherein, The two opposing, substantially flat, parallel marking display surfaces include at least one first sliding stop disposed behind the longitudinally extending guide rail and a second sliding stop disposed behind the first sliding stop.

10. The syringe according to claim 9, wherein, The rear end of the needle safety device engages with the first sliding stop in the first stop position, and wherein the rear end of the needle safety device engages with the second sliding stop in the second stop position to prevent subsequent rearward movement of the needle safety device from the second stop position toward the first stop position.

11. The syringe according to claim 1, wherein, The actuation handle also includes a touchpad.

12. The syringe according to claim 1, wherein, The first stop position is a fully retracted use position in which the needle tip shield substantially surrounds the nose and the front tip of the needle is exposed.

13. The syringe according to claim 12, wherein, The second stop position is the fully extended post-use position, in which the needle tip shield circumferentially surrounds and protects the front tip of the needle.

14. The syringe according to claim 1, wherein, The needle is configured to be fixed relative to the nose portion of the barrel.

15. The syringe of claim 14, further comprising a removable needle cap configured to cover the front tip of the needle when the needle safety device is in the first stop position, and the removable needle cap being disposed around the nose portion of the barrel.

16. The syringe according to claim 1, wherein, The cylinder also includes a rearward-facing clamp, the size and construction of which are designed to engage and support a removable piston cap.

17. The syringe according to claim 16, wherein, The cylinder includes a laterally extending finger-shaped flange, which is positioned in front of the rearward-facing clamp.

18. The syringe according to claim 1, wherein, The piston includes a piston seal that engages with the tubular sidewall of the fluid chamber.

19. The syringe according to claim 1, wherein, The volumetric dosage scale markings laterally overlap with at least a portion of the tubular sidewall of the fluid chamber.

20. The syringe according to claim 19, wherein, The volumetric dosage scale is positioned near the portion of the tubular sidewall of the fluid chamber, such that the volumetric dosage scale and the liquid level through the portion of the tubular sidewall are simultaneously visible.

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