Syringe with a flat marking surface

Abstract

The present invention relates to a syringe configured for medical use when aspirating or injecting fluids. [Solution] A medical syringe 20 having a barrel 22, the barrel 22 comprising a fluid chamber 25 which is substantially cylindrical and extends in the longitudinal direction, a needle retraction cavity which has substantially the same length as the fluid chamber 25 and is positioned adjacent to and substantially parallel to the fluid chamber 25, and a substantially flat, outward-facing display surface 23 which is positioned adjacent to the fluid chamber 25 on the same line as the fluid chamber 25 and is configured to receive and display an array of volume measurement markers.

Description

Background Art

[0001] The present invention relates to a syringe configured for medical use when sucking or injecting a fluid. The syringe preferably includes a barrel, a plunger slidably engaged with a part of the barrel, a needle protruding forward, and a substantially flat label display surface disposed on the barrel. One aspect of the present invention is a barrel in which a needle retraction cavity having a spread substantially the same as the length of the fluid chamber of the barrel is offset laterally. By laterally offsetting the needle retraction cavity having a sufficient length, it becomes possible to selectively use a long retractable needle used in a conventional safety syringe having a retractable needle, and without increasing the entire length of the syringe, the range of use of the device and the scope of performing a treatment can be expanded. This use and treatment of the device include, depending on the length of the needle, for example, performing a spinal puncture, administering an epidural anesthesia, sucking a cyst, etc., and in addition, injecting into the dermis, subcutaneous tissue or muscle.

[0002] Another aspect of the present invention relates to a syringe having a barrel, wherein the barrel includes a substantially cylindrical fluid chamber, a needle retraction cavity disposed parallel to and spaced laterally from the fluid chamber, and at least one substantially flat and outward-facing display surface, and indicia such as dosage graduations can be affixed to the display surface using a conventional pad printing process. Still another aspect of the present invention relates to a syringe having a barrel with two opposing substantially flat surfaces, and the same or different indicia can be pad printed on the surfaces without rotating the barrel even when printing on a syringe of 1 mL, 0.5 mL or smaller. The substantially flat display surface can also be used to affix labels to the syringe by other processes such as embossing and injection molding.

[0003] Another aspect of the present invention relates to a combination of a medical syringe having the barrel and plunger described above and a front attachment having a needle that protrudes forward and is biased backward. Preferably, the front attachment and the barrel are configured to work together such that the front attachment slides into the front portion of the barrel along an axis lateral to the longitudinal axis through which the needle passes.

[0004] <Explanation of related technologies> Medical syringes typically have a barrel with a roughly cylindrical inner and outer wall, meaning that markings such as dosage scales and other markings are applied to the curved outer surface during manufacturing. This is a difficult task, especially when the barrel diameter and radius of curvature of the outer wall are small (e.g., 1 mL, 0.5 mL, and smaller volume syringes) and the usable outer surface area is very limited, or when different dosage scales or other markings are applied to opposite sides of the barrel. In such cases, the barrel often has to be rotated during printing. Furthermore, reading the dosage scale lines and associated numbers or other markings is often difficult. This is because these markings wrap around the outer circumference of the barrel, and markings on one side may be visible through the syringe, potentially confusing the user or leading to medical malpractice. For at least these reasons, there is a need for syringes with a roughly flat surface for applying dosage and other markings.

[0005] Medical syringes in which a rearward-biased needle is retracted into a retraction cavity located coaxially within the plunger are known and have been disclosed to date, for example, in U.S. Patents 5,049,133, 5,053,010, 5,084,018 and 6,090,077. More recently, a medical syringe having a front attachment containing a rearward-biased needle, in which the needle is retracted into a needle retraction cavity that is part of the front attachment, has been disclosed, for example, in U.S. Patent 9,381,309.

[0006] More recently, a medical syringe has been disclosed having a barrel with a needle retraction cavity and a front attachment that slidably engages with the barrel, wherein the needle retraction cavity is integrally molded with the barrel and positioned parallel to the fluid chamber. For example, in U.S. Patent No. 9,814,841 (Figures 37-42), the needle retraction cavity is substantially shorter in length than the fluid chamber in the barrel, and therefore cannot cooperate with the outer wall of the barrel to form a substantially flat outer surface adjacent to the fluid chamber and having substantially the same width as the fluid chamber. [Overview of the project]

[0007] The disclosed medical syringe comprises an integrated barrel having a fluid chamber and a laterally offset needle retraction cavity, wherein the fluid chamber and the needle retraction cavity are substantially parallel and separated by a common wall. The needle retraction cavity has a non-circular cross-section and is preferably substantially the same length as the fluid chamber. This allows for the retraction of longer needles without increasing the overall length of the barrel, and enables the use of longer needles, such as in a safety syringe where the needle is retracted into the barrel after use. The barrel further comprises an outer wall having at least one substantially flat, outwardly facing display surface, on which markings, such as volume scales for dosage, can be affixed using conventional pad printing techniques or other alternative means having a similar effect. The at least one substantially flat display surface is preferably located close to the fluid chamber and preferably includes a measuring scale. The measuring scale is provided to be aligned longitudinally collinear with at least the portion of the fluid chamber used for injecting or aspirating fluid. In a preferred embodiment of the present invention, two substantially flat surfaces having the same longitudinal extent are arranged opposite each other, 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.

[0008] The present invention is particularly useful for syringes with a usable volume of 1 mL or less. Because these syringes generally have a small barrel diameter, the dosage volume marking applied to the outer surface wraps around most of the outer circumference of the barrel. In another preferred embodiment of the present invention, a pad printing technique (sometimes referred to as "tampography") is used to apply the dosage volume marking or other marking to a substantially flat display surface of the syringe. The needle retraction cavity has a non-circular cross-section (preferably molded from a suitable polymer material) and is laterally offset from the barrel, creating a broad, outward-facing, substantially flat display surface during manufacturing. The substantially flat display surface preferably includes at least one surface adjacent to the fluid chamber of the barrel. This surface allows, if necessary, the dosage volume marking or other marking to be molded onto another flat display surface or embossed onto or within the display surface.

[0009] Another embodiment of the syringe of the present invention includes a combination of the barrel and plunger described above with a front attachment having a needle that protrudes forward and is biased backward. The front attachment and the barrel preferably cooperate so that the front attachment slidably engages with the front portion of the barrel along an axis perpendicular to the longitudinal axis through which the needle passes. When the syringe is positioned for use, the needle is collinear with a first opening in the front portion of the barrel, and the opening communicates with a substantially cylindrical fluid chamber in the barrel, forming a coaxial fluid flow path between the fluid chamber and the needle. A fluid seal is seated around the first opening to prevent fluid leakage between the front attachment and the barrel. The needle retraction cavity extends backward from a second opening in the front portion of the barrel, parallel to and spaced apart from the fluid chamber of the barrel, and preferably shares a common wall with at least a portion of the fluid chamber. After use, the relative lateral movement between the barrel and the front attachment repositions the rearward-biased needle so that it aligns coaxially with the needle retraction cavity. This prevents the needle from protruding forward from the syringe, as it is then pushed into the retracted position by a biasing mechanism, typically such as a compression spring.

[0010] Another embodiment of the syringe of the present invention provides a wide, substantially flat display surface on the syringe, in which a single barrel and needle retraction cavity work in cooperation with a substantially flat edge of the surrounding flange to prevent the syringe from falling off a tray or other flat surface. Furthermore, the substantially flat surface allows the flange around the barrel to be proportionally narrower compared to the flange of conventional syringes with a tubular barrel, thereby increasing the surface area provided and making it easier for the user to understand the display surface. The substantially flat, opposing surfaces improve stability, thereby improving the user's control over operations performed on the syringe during injection or other processing. In the syringe of the present invention, the barrel having a laterally offset needle retraction cavity can be integrally molded with the fluid chamber, so that at least one, preferably two (opposing) substantially flat, outward-facing surface areas are provided. This surface area is useful for arranging volumetric scales and other markings, making them easier for users to read and reducing the possibility of administration errors during aspiration or injection.

[0011] Another embodiment of the present invention combines the syringe of the present invention with a selectively removable needle cover, the needle cover including a locking member which engages with a portion of the barrel to prevent the barrel from sliding laterally relative to the front attachment, thereby preventing accidental retraction of the needle before the syringe is used. Retraction of the needle after the syringe is used reduces the reusability of the syringe, the likelihood of accidental needle prick, and the likelihood of accidental infection by bloodborne pathogens.

[0012] Another embodiment of the present invention combines the syringe of the present invention with a plunger cap, which is detachably mounted on the rear of the syringe, typically behind the finger flange, and can be selectively removed before aspirating or using the fluid. When both the needle cover and the plunger cap are in place, the needle and the fluid contact area inside the syringe are surrounded and protected from contamination, regardless of whether the syringe is sealed in a separate package. Thus, the syringes can be assembled and shipped in large quantities before packaging and sterilization.

[0013] The syringe of the present invention is particularly useful for administering relatively small amounts of drug solutions, such as insulin or vaccines, to a user by injection or infusion, but the structure and operation of the device are not limited to a specific size, dose, or process. For example, the syringe disclosed herein may also be configured for use in aspirating fluid samples from a patient in clinical procedures such as knee or spinal puncture. By using the front attachment in combination with the novel barrel of the present invention, the overall length of the syringe is reduced, so that a long needle can be used and retracted into the syringe after use. As used in this disclosure, the terms “retracted” or “retraction” refer to the process by which the needle tip moves from a forward-protruding use position to a post-use position where it does not protrude forward from the front attachment, by a force acting on the needle pushing or pulling the needle tip backward from a forward-protruding position.

[0014] These and other features of the present invention will be better understood by examining them together with the following detailed description of various embodiments, the appended claims and drawings. [Brief explanation of the drawing]

[0015] The syringe of the present invention will be further described in reference to the following drawings. [Figure 1]Figure 1 is a top-down front perspective view of one embodiment of the present invention, in which the needle cover (including a locking member) and plunger end cap are positioned where the syringe of the present invention is packaged, shipped, and stored, and the locking member of the needle cover restricts the lateral sliding movement of the barrel relative to the front attachment before use. [Figure 2] Figure 2 is a top-down front perspective view of the embodiment shown in Figure 1, with the needle cover removed. [Figure 3] Figure 3 is an exploded view of the embodiment shown in Figure 1, viewed from above as a front perspective. [Figure 4] Figure 4 is a right side view of the embodiment shown in Figure 2. [Figure 5] Figure 5 is a cross-sectional view along the line 5-5 in Figure 4. [Figure 6] Figure 6 is a detailed exploded perspective view showing the front attachment, which is positioned alongside the front portion of the barrel in the embodiment shown in Figure 3, with a portion of it broken off. [Figure 7] Figure 7 is a rear perspective view of the front attachment shown in Figure 3, viewed from above. [Figure 8] Figure 8 is a right side view of the embodiment shown in Figure 4, in which the plunger cap has been removed and the plunger has been retracted to the suction position. [Figure 9] Figure 9 is a cross-sectional view along the line 9-9 in Figure 8. [Figure 10] Figure 10 is a right side view of the embodiment shown in Figure 8, where the needle is retracted and the plunger is fully advanced within the barrel. [Figure 11] Figure 11 is a cross-sectional view along the line 11-11 in Figure 10. [Figure 12] Figure 12 is a front view of the embodiment shown in Figure 2. [Figure 13] Figure 13 is a front view of the embodiment shown in Figure 12, in which the front attachment has been repositioned relative to the barrel and the needle has been retracted to the position shown in Figures 10 and 11. [Modes for carrying out the invention]

[0016] Referring to Figure 1, the syringe 20 comprises a barrel 22, which further includes a substantially flat display surface 23, a front attachment 24, an outer wall 25 of a fluid chamber 75 (as seen in Figure 9), a selectively removable needle cover 26, a volumetric measuring indicia 27, a finger flange 28, a removable plunger cap 30, and a locking member 40. As shown in Figure 1, the main volumetric measuring indicia 27 is applied to the display surface 23. The volumetric measuring indicia includes, for example, Arabic numerals indicating fluid units and the associated main measuring indicia. Note that the numbers in the drawings are illustrative and not drawn to exact scale, and the arrangement of some features, such as the secondary unit mark 27, with respect to the substantially flat display surface 23 can be changed from the positions shown. Each of the secondary (individual) unit markers or marks preferably begins in close proximity to the display surface 23 or the edge of the display surface 23, and optionally extends slightly to the curved outer wall of the fluid chamber 25. Such arrangements are recognized as being within the operational capabilities of known pad printing techniques and are now readily available to those skilled in the art.

[0017] In Figure 1, the front attachment 24 of the syringe 20 is shown in its "before use" state. Before use, the needle cover 26 and locking member 40 are positioned to prevent the front attachment 24 from moving laterally relative to the barrel 22, as pressure may be inadvertently applied to the textured touchpad 46 or the opposite side of the barrel 22. A removable plunger cap 30 is provided behind the finger flange 28 to prevent the plunger (not shown) from being accidentally pulled out of the barrel 22 and to prevent inadvertent contamination of the inside of the rear opening of the barrel 22 or the area around the handle portion (see Figure 9) extending behind the plunger, which will be described later.

[0018] Referring to FIGS. 2, 4-5 and 12, the barrel 22 and the front attachment 24 of the syringe 20 are shown in the same position as in FIG. 1, which is different from FIG. 1 in that the needle cover 26 (having the locking member 40) is removed. The front opening of the needle retraction cavity 92 is shown, and the needle 34 projects forward from the needle support member 32 of the front attachment 24. Circumferentially spaced and axially tapered ribs 33 are disposed around the needle support member 32. The ribs 33 provide a surface for frictionally engaging the inner surface of the needle cover 26 before it is removed. In FIG. 2, the needle 34 is preferably disposed coaxially with the longitudinal axis passing through the fluid chamber 75 (FIG. 9).

[0019] Referring to FIG. 3, the needle cap 26 of the syringe 20 further includes a generally cylindrical side wall that is forward-facing and inwardly tapered, the side wall having a front end 36, a rearward annular collar 38, and a locking member 40 that projects rearward from the annular collar 38. The front attachment 24 further includes a generally tubular needle support member 32 having a front opening 42 and projecting forward, an upper guide member 44, a lower guide member 45 (see FIG. 7), and a laterally projecting textured touch pad 46.

[0020] The syringe 20 preferably includes a needle 34 having a forwardly angled needle tip 48, and a needle retraction mechanism having a compression coil spring 50 and a needle holder 52. The needle holder 52 includes an elongated shaft 54 having a tubular bore 58 that is insertable into the rear portion of the spring 50. The diameter of the head 56 of the needle holder 52 is sufficiently larger than the inner diameter of the spring 50 such that when the front attachment 24 slidably engages the front portion 64 of the barrel 22, the spring 50 can be held in a compressed state by the head 56. This will be described below in connection with FIGS. 6 and 7. The rear end portion of the needle 34 is insertable into the tubular bore 58 of the needle holder 52 and can be attached in a fixed relationship within the elongated shaft 54 by any suitable means commercially available such as an adhesive. The needle retraction mechanism disclosed herein is sufficient for use within the syringe 20, but it will be understood that other similar elements and mechanisms can be used in the practice of the present invention if they provide a similar effect and are useful for biasing the needle 34 rearwardly within the syringe 20.

[0021] Referring again to FIG. 3, an annular polymeric fluid seal 60 having a tubular bore 62 is preferably insertable into a recess 66 in the front portion 64 of the barrel 22. In the needle retraction mechanism disposed within the front attachment 24, when the front attachment 24 slidably engages the front portion 64 of the barrel 22, the forward end of the seal 60 is in contact with the rearward head 56 of the needle holder 52. In manufacture, when the front attachment 24 of the syringe 20 is assembled to the front portion 64 of the barrel 22, a continuous and substantially straight fluid flow path is formed through the needle 34, the needle holder 52, and the annular fluid seal 60 and into a longitudinally extending, tubular fluid chamber 75 (see FIG. 9).

[0022] The barrel 22, in addition to the front portion 64, further includes a substantially flat display surface 23, a curved outer wall surface 25, a finger flange 28, and a rearward-projecting annular collar 70. For assembly of the syringe 20, it is preferable to position an elastomer plunger seal 76 on a boss 74 projecting forward at the front end of the plunger handle 72, opposite the rearward-facing plunger thumb pad 78, and then insert the plunger handle 72 into the rearward-facing opening defined by the annular collar 70. Assembly of the syringe 20 is completed by attaching a substantially cylindrical plunger cap 30 to the rearward-facing end of the barrel 22. The plunger cap 30 further includes an open front end 80, a cylindrical bore 82, and a closed rear end 84. The plunger cap 30 is mounted around the plunger thumb pad 78 and frictionally engages with the outer wall of the annular collar 70. The volume measurement markings 27, as described in relation to Figure 1, can also be seen on the outward-facing portion of the substantially flat display surface 23 and the curved outer wall surface 25.

[0023] Figures 3, 6, and 11 further show the forward-facing opening in the needle retraction cavity 92 with respect to 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 bounded by side walls 90, 95, a bottom wall 94, and a top wall, the top wall including the upward-facing, substantially flat display surface 23 of the barrel 22.

[0024] The assembly of the front attachment 24 to the front portion 64 of the barrel 22 will be further described with reference to Figures 6 and 7. Referring to Figure 6, first, the annular fluid seal 60 (see Figure 3) is inserted into the recess 66 of the front portion 64 of the barrel 22. The front portion 64 further includes a laterally extending upper rail 68 and a lower rail 69, which are positioned laterally with respect to the longitudinal axis passing through the fluid chamber 75 (Figure 9) of the barrel 22. Rounded mounting guides 96, 98 are positioned in front of the upper rail 68 and the lower rail 69, respectively, and the front attachment 24 is configured to be assembled to the front portion 64 of the barrel 22 by passing the upper and lower arms connecting to the textured touchpad 46 through to the rear of the front attachment 24.

[0025] Referring to Figure 7, an annular opening 112 is provided on the back of the front attachment 24. The opening 112 allows for the insertion of the spring 50 and needle holder 52 as described in relation to Figure 3. The spring 50 is preferably compressed between the annular shoulders (see Figure 11) within the front opening 42, and is maintained in a compressed state behind the head 56 of the needle holder 52 while the front attachment 24 slides along the front portion 64 of the barrel 22. The front attachment 24 further includes an upper guide 44 having a downwardly and laterally extending recess 100 and a lower guide 45 having an upwardly and laterally extending recess 102. The upper ramp 104 and lower ramp 106 of the front attachment 24 have blocking shoulders 77, 79, respectively, and are configured to slide over two laterally spaced and opposing ramps (the lower ramp is not visible in Figure 6). When the front attachment 24 and front portion 64 are in the position shown in Figure 6, it is preferable that the upper rail 68 and lower rail 69 extending laterally from the front portion 64 of the barrel 22 engage in cooperation with the upper recess 100 and the lower recess 102, respectively, by sliding the front attachment 24 onto the front portion 64 of the barrel 22. When pressure is applied to the textured touch surface 46, the front attachment 24 moves along the rails 68 and 69, and the upper and lower blocking shoulders 108 of the upper guide 44 pass over the upper and lower blocking shoulders 77, and then face the upper and lower blocking shoulders 77. At this time, it is preferable that the needle support member 32 and the needle holder 52 (not shown in Figures 6 and 7) are located coaxially with the longitudinal axis of the fluid chamber 75 (see Figure 9). Because the upper and lower blocking shoulders 77 of the front part 64 and the upper blocking shoulder 108 and lower blocking shoulder 110 of the front attachment 24 are in contact with each other, the front attachment 24 cannot be returned to its detached position (Figure 6).

[0026] Figures 4 and 5 show the syringe of Figure 2 with the needle cover removed, the plunger cap 30 held in place, and the textured touch surface 46 in the initial position relative to the barrel 22 as described above. The needle 34 is positioned within the bore 58 of the needle holder 52, which seats within the needle support member 32 of the front attachment 24, and the spring 50 is compressed between the heads 56 (Figure 3) of the needle holder 52. The needle holder 52 and the needle 34 are biased rearward by the spring 50, and the needle 34 contacts the front surface of the annular fluid seal 60. This forms a linear fluid passage through the needle 34, needle holder 52, and fluid seal 60 to the fluid chamber 75 (see Figure 9) of the substantially cylindrical barrel 22. As shown in Figures 4 and 5, the plunger seal 76 is fully pushed into the substantially cylindrical fluid chamber 75 of the barrel 22.

[0027] Referring to Figures 8-9, with the textured touchpad 46 back in its initial position, the fluid is drawn into the syringe 20. While the fluid is being drawn into the fluid chamber 75, the plunger cap 30 (see Figures 2, 4-5) is removed and the plunger handle 72 is retracted. In Figure 9, the needle retraction cavity 92 is approximately the same length as the fluid chamber 75. This allows the volumetric marker 27 to be placed on a nearly flat surface 23 (see Figure 3), enabling full utilization of the volume of the fluid chamber 75 and allowing for the retraction of needles such as biopsy needles that are substantially longer than the needle 34 (seen in the needle retraction cavity 92 in Figure 11). Once the fluid is drawn into the fluid chamber 75, the fluid can be injected into the patient or dispensed from the fluid chamber 75 by pushing the plunger thumb pad 78 forward and applying pressure with the finger against the forward-facing surface of the flange 28.

[0028] Referring to Figures 10-11 and 13, the plunger handle 72 and plunger seal 76 are pushed forward to empty the fluid chamber 75. Pressure is applied to the textured touchpad 46 to initiate needle retraction, which moves the front attachment so that the needle support member 32 is aligned with the needle retraction cavity 92. Since the front opening of the needle retraction cavity 92 is larger than the head 56 of the repositioned needle holder 52, the needle holder 52 is pushed backward by the biasing force of the compression spring 52, and the needle holder 52 and needle 34 move into the distal end of the needle retraction cavity 92.

[0029] Referring again to Figures 6 and 7, when further force is applied to the textured touch surface 46 of the front attachment 24 relative to the barrel 22 as described in Figures 10-11, the front attachment 24 and the front portion 64 of the barrel 22 slide relative to each other. This movement causes the upper inclined surface 104 and the lower inclined surface 106 to slide over the second opposing inclined surface and blocking shoulder 79, so that the upper blocking shoulder 108 and the lower blocking shoulder 110 come into contact with the upper and lower blocking shoulders 79. As a result, the front attachment 24 does not return to its use position relative to the barrel 22.

[0030] Experts in the field will be able to make various other modifications and changes to the embodiments disclosed herein by reading this specification together with the accompanying drawings. The scope of the invention disclosed herein is limited only by the broadest interpretation of the attached claims to which the inventor has legal rights.

Claims

1. A medical syringe equipped with an integrated barrel, A syringe comprising an integrated barrel including a fluid chamber, wherein the outer wall of the barrel has at least one substantially flat marking surface positioned adjacent to the fluid chamber.

2. The syringe according to claim 1, comprising two opposing substantially flat marking surfaces, wherein one of the substantially flat marking surfaces is positioned on each of the two opposing surfaces of the barrel.

3. The syringe according to claim 1, wherein at least one substantially flat marking surface is marked with a volume scale.

4. The syringe according to claim 3, wherein the volume scale is collinear with a portion of the fluid chamber in the longitudinal direction.

5. A medical syringe equipped with an integrated barrel, The syringe comprises a fluid chamber and a laterally offset needle retraction cavity, wherein the fluid chamber and the needle retraction cavity are integrally molded and have substantially the same extent in the longitudinal direction.

6. The syringe according to claim 5, wherein the fluid chamber and the needle retraction cavity are separated by a common wall.

7. The syringe according to claim 5, further comprising at least one substantially flat display surface on the outer wall of the barrel, positioned in close proximity to the fluid chamber.

8. The syringe according to claim 7, comprising two substantially flat, opposing display surfaces.

9. The syringe according to claim 7, wherein at least one substantially flat display surface is marked with a volume scale.

10. The syringe according to claim 9, wherein the volume scale is collinear with a portion of the fluid chamber in the longitudinal direction.

11. The syringe according to claim 7, wherein at least one substantially flat display surface, each display surface, is at least partially located on at least a portion of the needle retraction cavity.

12. The syringe according to claim 5, further comprising a plunger slidably engaged with the rear of a fluid chamber, and a front attachment slidably engaged with the front of a barrel in a direction transverse to the longitudinal axis of the plunger.

13. The syringe according to claim 12, further comprising a needle that protrudes forward and is biased backward, the needle seating inside a front attachment and selectively retractable into a needle retraction cavity after use.

14. A medical syringe equipped with an integrated barrel, The integrated barrel includes a fluid chamber and a laterally offset needle retraction cavity, the fluid chamber and the needle retraction cavity being integrally molded, having substantially the same extent in the longitudinal direction, being substantially parallel, and separated by a common wall. A syringe having at least one substantially flat display surface, preferably located on the outer wall of the barrel, in close proximity to the fluid chamber.

15. The syringe according to claim 14, comprising two opposing, substantially flat display surfaces.

16. The syringe according to claim 14, wherein at least one substantially flat display surface is marked with a volume scale.

17. The syringe according to claim 16, wherein the volume scale is collinear with a portion of the fluid chamber in the longitudinal direction.

18. The syringe according to claim 14, wherein at least a portion of at least one substantially flat display surface is located above at least a portion of the needle retraction cavity.

19. The syringe according to claim 14, further comprising a plunger slidably engaged with a fluid chamber, and a front attachment slidably engaged with the front portion of a barrel in a direction transverse to the longitudinal axis of the plunger.

20. The syringe according to claim 12, wherein the front attachment further includes a needle that protrudes forward and is biased backward, the needle seating inside the front attachment and being selectively retractable into a needle retraction cavity after use.

21. It is a syringe, A barrel comprising a fluid chamber that extends longitudinally and is substantially cylindrical in shape, and a needle retraction cavity that has substantially the same length as the fluid chamber and is arranged adjacent to and parallel to the fluid chamber, A plunger having an axis in the longitudinal direction and slidably engaging with the inner wall of the fluid chamber, A front attachment is positioned laterally to the longitudinal axis of the plunger and slidably engages with the front portion of the barrel, A needle that protrudes forward and is biased backward, which is seated within the front attachment and can be selectively retracted after use, The syringe further includes at least one substantially flat outward-facing display surface, the display surface being configured to receive and display a volume measurement mark visible to the user during use of the syringe, the mark being located in close proximity and on the same line as the fluid chamber.

22. The syringe according to claim 21, wherein the barrel of the syringe includes two substantially flat, opposing display areas.

23. The syringe according to claim 21, wherein at least one substantially flat display area is affixed together with a volume measurement mark.

24. The syringe according to claim 22, which is attached to each display area of ​​the opposing display area together with a volume measurement mark.

25. The syringe according to claim 21, wherein the volume measurement mark is applied to the display area by at least one of the group consisting of molding, stamping, embossing, or printing.

26. The syringe according to claim 24, wherein a volume measurement mark attached to one display area is different from a volume display mark attached to an opposing display area.

27. The syringe according to claim 21, further comprising a removable needle cover.

28. The syringe according to claim 27, further comprising a locking member, which includes a removable needle cover.

29. The syringe according to claim 28, wherein the locking member is a locking arm extending into the needle retraction cavity.

30. The syringe according to claim 21, further comprising a selectively removable plunger cap.

31. A medical syringe having a barrel, wherein the barrel is A fluid chamber that is roughly cylindrical and extends in the longitudinal direction, A needle retraction cavity having approximately the same length as the fluid chamber and positioned adjacent to and approximately parallel to the fluid chamber, A substantially flat, outward-facing display area is provided, located on the same line as the fluid chamber and adjacent to the fluid chamber, and configured to receive and display an array of volume measurement markers. A medical syringe equipped with medical supplies.

32. The syringe according to claim 31, wherein the needle retraction cavity has a non-circular cross-section and shares a common wall with at least a portion of the fluid chamber.

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