Dual fluid cartridge assembly

Abstract

The invention relates to a dual fluid cartridge assembly. A dual fluid cartridge assembly (30) includes a cartridge (32), a flange (56), and a piston tube (36). A barrel defines a channel and includes the flange. The flange defines a cavity (78) extending from a cavity opening (80) to a cavity base (82). The cavity opening is located within the passage of the cartridge and the cavity base is located outside the cartridge. The piston tube has an extended end (57) and is located at least partially within the passage. The extending end is located in the cavity.

Description

[0001] Divisional Application

[0002] This application is a divisional application of Chinese Patent Application No. 201880015328.7, filed on January 26, 2018, having a title of “Dual Fluid Cartridge Assembly”.

[0003] Cross Reference to Related Applications

[0004] This application claims priority to U.S. Provisional Patent Application No. 62 / 453,731, filed February 2, 2017, the disclosure of which is incorporated herein by reference. TECHNICAL FIELD

[0005] The present disclosure relates generally to dual fluid cartridge assemblies, and more particularly, to systems and methods for connecting a piston seal and a delivery tube within a dual fluid cartridge assembly. BACKGROUND

[0006] Single and multiple fluid cartridge assemblies are generally known for dispensing fluid materials, such as reactive adhesives, which typically include two components that need to be kept separate and quickly applied after mixing. An example of a single fluid cartridge assembly is disclosed in commonly owned International Patent Application No. PCT / US02 / 39041, filed December 6, 2002. Examples of multiple fluid cartridge assemblies are disclosed in, for example, U.S. Patent Nos. 4,220,261; 4,961,250; and 5,310,091.

[0007] In U.S. Patent No. 5,310,091, a dual fluid cartridge includes a front chamber and a rear chamber formed by an outer cartridge and an inner cartridge, respectively. A piston seal is used to separate the fluids within the cartridge. Movement of the inner cartridge under the influence of a plunger causes the inner cartridge and the upper piston to advance axially within the outer cartridge. The inner cartridge is in fluid communication with a piston tube that extends through the front chamber to a cartridge outlet. Movement of the inner cartridge within the outer cartridge causes the fluids in the inner cartridge and the outer cartridge to be dispensed. To fill the inner chamber and the outer chamber with fluid, the fluid is forced into the cartridge outlet, thereby forcing the inner cartridge and the upper piston to retract axially within the outer cartridge.

[0008] During the process of filling the inner barrel chamber and the outer barrel chamber with fluid, a force is provided to the piston tube that can cause the piston tube to fall off the outer barrel. While the risk of falling off is generally low, the severity of the problem that can result can be very high. In conventional systems, it is difficult to detect whether the piston tube has fallen off the outer barrel and can involve, for example, a pneumatic test or a destructive analysis. The pneumatic test involves separately checking the pneumatic decay of the air pressure in the outer barrel chamber and in the inner barrel chamber and then together checking the pneumatic decay of the air pressure of both chambers. If both chambers separately exhibit a large pressure decay and both chambers together do not exhibit a large pressure decay, this indicates that the piston tube has fallen off the barrel assembly. However, the pneumatic test can be time consuming and expensive and requires suitable test equipment. The destructive analysis involves disassembling or damaging the fluid barrel, which can render the fluid barrel inoperable.

[0009] Therefore, there is a need for an improved system and method for filling and dispensing fluid from a barrel assembly and for detecting whether a piston tube has fallen off an outer barrel. SUMMARY

[0010] The foregoing needs are largely satisfied by a dual fluid barrel assembly disclosed in the present application. The dual fluid barrel assembly includes an outer barrel and a piston tube. The outer barrel extends in an axial direction from a proximal end to a distal end. The outer barrel includes a base wall having an inner edge. The base wall is positioned toward the distal end of the outer barrel. A flange extends at least partially along the inner edge of the base wall and defines a cavity that extends in the axial direction from a cavity opening to a cavity base. The cavity base is distal from the base wall in the axial direction. The piston tube has an extended end that is located within the cavity.

[0011] An alternative aspect of the dual fluid barrel assembly includes an outer barrel and a piston tube. The outer barrel includes a base wall and a flange. The base wall has an inner edge that defines a barrel outlet. The flange extends at least partially along the inner edge of the base wall and defines a cavity that extends in an axial direction from a cavity opening to a cavity base. The base wall is distal from the cavity opening in the axial direction and the cavity base is distal from the base wall in the axial direction. The piston tube has an extended end that is located within the cavity.

[0012] An alternative aspect of the dual fluid barrel assembly includes a barrel that defines a passageway, a flange, and a piston tube. The flange is coupled to the barrel and defines a cavity that extends from a cavity opening to a cavity base. The cavity opening is located within the passageway of the barrel and the cavity base is located outside of the barrel. The piston tube is at least partially located within the passageway. The piston tube has an extended end that is located within the cavity.

[0013] Another aspect of the dual-fluid cartridge assembly includes an outer cartridge, an upper seal, an inner cartridge, and a piston tube. The outer cartridge carries a first fluid and includes a cartridge wall, a base wall, and a flange. The cartridge wall defines a passageway. The base wall has an inner edge that defines a cartridge outlet. The flange extends at least partially along the inner edge of the base wall and defines a cavity that extends in an axial direction from a cavity opening to a cavity base. The base wall is distal from the cavity opening in the axial direction and the cavity base is distal from the base wall in the axial direction. The upper seal is positioned within the passageway and is configured to seal the first fluid in the outer cartridge. The inner cartridge carries a second fluid. The piston tube is positioned at least partially within the passageway. The piston tube has an extended end that is positioned within the cavity. The piston tube is configured to provide a fluid flow path from the inner cartridge to the cartridge outlet. BRIEF DESCRIPTION OF DRAWINGS

[0014] The foregoing summary, as well as the following detailed description of illustrative embodiments of the present application, can be better understood when read in conjunction with the accompanying drawings, which are included as a part of the detailed description. For the purpose of illustrating the present application, there is shown in the drawings illustrative embodiments of the present disclosure. However, it should be understood that the present application is not limited to the precise arrangements and instrumentalities shown. In the drawings:

[0015] Figure 1 A perspective view of a dual-fluid cartridge assembly is shown.

[0016] Figure 2 A cross-sectional view of the dual-fluid cartridge assembly shown in Figure 1 FIG. 2 taken along line 2-2 in a filled position.

[0017] Figure 3 Another cross-sectional view of the dual-fluid cartridge assembly shown in Figure 1 FIG. 2 taken along line 2-2 in an empty position.

[0018] Figure 4 is a simplified view of a portion of a vent path formed in the inner cartridge.

[0019] Figure 5 is a right side view of the inner cartridge shown in Figure 4 FIG. 4.

[0020] Figure 6 is a cross-sectional view of the inner cartridge taken along line 8-8 of Figure 5 FIG. 4.

[0021] Figure 7 is a left side view of the inner cartridge shown in Figure 4 FIG. 4.

[0022] Figure 8A is an enlarged detail view of a cross-section of a distal end of the dual- fluid cartridge assembly shown in Figure 2 FIG. 2.

[0023] Figure 8B isFigure 8A enlarged detail view of a cross section of the distal end of the dual cartridge assembly shown in

[0024] Figure 9 is an enlarged partial transparent view of the distal end of the dual cartridge assembly. DETAILED DESCRIPTION

[0025] A dual cartridge assembly for separately carrying two separate fluids, such as a resin and a hardener, is disclosed. The cartridge assembly can be mated with a conventional mixing nozzle to enable the mixed fluids to be applied to a workpiece by a standard dispensing device, such as a caulk gun. The cartridge assembly reduces the risk of parts falling out or breaking during operation and has improved interfaces between parts and increased failure detection capabilities.

[0026] Certain terminology is used in this description for convenience only and is not intended to be limiting. The words "proximal" and "distal" generally refer to positions or directions toward and away from, respectively, an individual operating the cartridge assembly. The words "axial", "radial" and "transverse" denote directions in the referenced drawings. The term "substantially" is intended to mean to a great or significant extent or largely but not necessarily entirely as specified. The terminology includes the words above, derivatives thereof and words of similar import.

[0027] Figure 1 A dual cartridge assembly 30 is shown. The cartridge assembly 30 is adapted to be dispensed by a caulk gun 20 that includes a plunger (not visible in the figures), a handle 24 and a trigger 26. The cartridge assembly 30 is inserted into the caulk gun 20 in a conventional manner. With the ratchet arm 32a in the position shown in Figure 1 With the trigger 26 being squeezed toward the handle 24, the plunger 22 advances in the axial direction A toward the distal end 28 of the cartridge assembly 30. As will be discussed in greater detail below, movement of the plunger 22 from the proximal end 27 of the cartridge assembly 30 toward the distal end 28 of the cartridge assembly 30 results in axial movement of an inner cartridge located within an outer cartridge of the cartridge assembly 30. The axial movement of the inner cartridge within the outer cartridge results in the fluids being dispensed and applied to a workpiece through a cartridge outlet and a nozzle, such as a static mixing nozzle, in a manner similar to that disclosed in U.S. Patent No. 5,310,091, which is incorporated herein by reference.

[0028] The cartridge assembly 30 can be provided with a venting path to atmosphere that allows air in the inner cartridge and, optionally, the outer cartridge to be vented to atmosphere during the filling process to prevent air pockets from being trapped therein. Such trapped air pockets are known to create voids in the fluids in the inner cartridge and the outer cartridge, resulting in uneven mixing of the fluids and, thus, reduced performance of the fluids.

[0029] Figure 2 and Figure 3A cross-sectional view of the cylindrical assembly 30 is shown. Figure 2 The cylinder assembly 30 is in the filling position, while Figure 3 The cylinder assembly 30 is in the vented position. The cylinder assembly 30 includes an outer cylinder 32, an inner cylinder 34, an integral piston seal with a lower sealing portion 39 and a piston tube 36, and an upper seal 38.

[0030] like Figure 3 As shown, when the inner cylinder 34 is in the emptied position, a venting path to the atmosphere can be established from the inner cylinder 34. Filling of the inner cylinder 34 can be accomplished through the cylinder outlet 40. The cylinder outlet 40 includes a nose 29 and a shoulder 31. The nose 29 is distal to the shoulder 31 and is formed as a tubular member with an axial partition wall 41 that forms two side-by-side chambers for filling each fluid. To fill the inner cylinder 34, fluid is applied through the cylinder outlet 40 and via the piston tube 36 to the rear chamber 47 forming the inner cylinder 34. Similarly, the front chamber 45 formed within the outer cylinder 32 is also filled through the cylinder outlet 40.

[0031] Figures 4 to 7 The inner cylinder 34 is shown. The inner cylinder 34 includes a circular base plate 42 and a cylindrical sidewall 44. A rod 46 (also referred to as a "separator rod" or "exhaust rod") projects distally from the base plate 42 and extends to an opening 43 in the cylindrical sidewall 44 of the inner cylinder 34. A slot 48 is, for example, a radial slot formed in the base plate 42 of the inner cylinder 34. The slot 48 formed in the base plate 42 of the inner cylinder 34 extends partially upward along the cylindrical sidewall 44 in the axial direction A, as indicated by reference numeral 50. The slots 48 and 50 are configured to allow air trapped in the inner cylinder 34 to escape upward along the cylindrical sidewall 44 of the inner cylinder 34 and to be discharged to the outside of the inner cylinder 34 through one or more notches 52 formed at the opening 43 of the inner cylinder 34. One or more axial slots 54 (see Figure 1) are formed in the inner sidewall of the outer cylinder 32. Figure 3 This allows air from the inner cylinder 34 to escape to the atmosphere through the axial slot 54. As the piston seal and the lower seal 39 of the piston tube 36 move away... Figure 3 In the venting position shown, the venting path is closed. The piston seal and the lower seal 39 of the piston tube 36 may be formed with a circumferential slot (not shown), for example, to receive an O-ring (not shown). The lower seal 39 seals the fluid in the inner cylinder 34 to isolate it from the rest of the cylinder assembly 30.

[0032] Figure 8A It shows Figure 2A detailed cross-sectional view of the distal end 28a of the outer barrel 32 is shown in FIG. 3. The outer barrel 32 is formed as a cylindrical member having a base wall 33 and a cylindrical side wall 35. The base wall 33 is positioned toward the distal end 28a of the outer barrel 32 and extends inwardly in a radial direction from the cylindrical side wall 35. The radial direction can be generally perpendicular to the axial direction A. The base wall 33 has an outer edge 77 that extends around the perimeter of the base wall 33. The cylindrical side wall 35 extends proximally from the outer edge 77 and defines a passageway 49 that extends through the outer barrel 32 from the proximal end 27a toward the distal end 28a (see FIG. 2). The diameter of the cylindrical side wall 35 is slightly larger than the diameter of the inner barrel 34 to allow the inner barrel 34 to move freely axially within the passageway 49. Figure 2 ) The cylindrical side wall 35 extends proximally from the outer edge 77 and defines a passageway 49 that extends through the outer barrel 32 from the proximal end 27a toward the distal end 28a (see FIG. 2). The diameter of the cylindrical side wall 35 is slightly larger than the diameter of the inner barrel 34 to allow the inner barrel 34 to move freely axially within the passageway 49.

[0033] The outer barrel 32 can be coupled to or formed with the barrel outlet 40 for filling the inner barrel 34 and the outer barrel 32 and dispensing fluid from the inner barrel 34 and the outer barrel 32. The outer barrel 32 includes a flange 56 for connecting to the piston tube 36. The connection between the flange 56 and the piston tube 36 generally prevents any mixing of fluid in the front chamber 45 or the back chamber 47. In one aspect, the flange 56 is integrally formed with the outer barrel 32 adjacent to the base wall 33. The piston seal and the piston tube 36 include a delivery tube portion 37 and an extension end portion 57. The delivery tube portion 37 forms a conduit from the inner barrel 34 to the barrel outlet 40. The delivery tube portion 37 can have a cylindrical shape. Fluid in the inner barrel 34 is dispensed through the delivery tube portion 37 and through an inner opening 58 to the barrel outlet 40. Fluid in the outer barrel 32 is dispensed into an outer opening 60. Thus, the inner opening 58 and the outer opening 60 formed along the base wall 33 of the outer barrel 32, along with the axial partition wall 41, allow fluid from the inner barrel 34 and the outer barrel 32 to be discharged separately side-by-side from the barrel outlet 40.

[0034] The flange 56 includes an inner flange wall 70, an outer flange wall 72, and a base flange wall 74 connecting the inner flange wall 70 to the outer flange wall 72. The flange 56 extends at least partially along the inner edge 76 of the base wall 33. The flange 56 can extend circumferentially about the axial direction A.

[0035] The inner flange wall 70, the outer flange wall 72, and the base flange wall 74 define a cavity 78 within the flange 56. The cavity 78 extends in the axial direction A from a cavity opening 80 to a cavity base 82. The cavity opening 80 is open to the passageway 49 defined by the outer barrel 32. The inner flange wall 70 has an inner flange surface 84 extending circumferentially about the axial direction A to define the inner opening 58 and a flange passageway 86. The inner flange wall 70 can be connected to the shoulder 31 of the barrel outlet 40 and the axial partition wall 41. The flange passageway 86 is in fluid communication with the inner opening 58 and the delivery tube portion 37 such that fluid dispensed from the inner barrel 34 flows through the delivery tube portion 37, the flange passageway 86, and the inner opening 58 to the barrel outlet 40.

[0036] The cavity 78 is configured to receive the piston seal and the extended end 57 of the piston tube 36 therein. In one aspect, the extended end 57 can define at least one circumferential slot 88 extending around the extended end 57. The flange 56 can define at least one mating slot 90 within the cavity 78. The at least one mating slot 90 can cooperate with the at least one circumferential slot 88. The cooperation between the at least one mating slot 90 and the at least one circumferential slot 88 can form a snap clip between the flange 56 and the piston tube 36. An adhesive can also be used to further secure the piston tube 36 within the cavity 78 of the flange 56.

[0037] The base flange wall 74 is positioned away from the base wall 33 such that the flange 56 protrudes from the base wall 33 in the axial direction A. In one aspect, the cavity base 82 can also be positioned away from the base wall 33 in the axial direction A such that the cavity base 82 is external to the outer barrel 32. The extended end 57 can extend beyond the base wall 33 in the axial direction A when the piston tube 36 is positioned within the cavity 78. The extended end 57 can be proximate to or in contact with the cavity base 82.

[0038] The cavity opening 80 can be positioned closer to the proximal end 27a of the outer barrel 32 than the base wall 33 such that the base wall 33 is distal from the cavity opening 80 in the axial direction A. In this configuration, the base wall 33 is positioned between the cavity opening 80 and the cavity base 82 in the axial direction A. Alternatively, the cavity opening 80 can be coplanar or flush with the base wall 33.

[0039] The shoulder 31 of the barrel outlet 40 can be attached to the flange 56 and to an axial shoulder 92. The axial shoulder 92 extends from the base wall 33 in the axial direction A. Alternatively, the shoulder 31 can be attached to the flange 56 and directly to the base wall 33. The shoulder 31 forms a portion of a first flow passage 94 and a portion of a second flow passage 96. The first flow passage 94 is in fluid communication with the inner opening 58 and the second flow passage 96 is in fluid communication with the outer opening 60. The shoulder 31 can be angularly offset from the axial direction A to form at least a partial conical shape.

[0040] In one aspect, each component of the barrel assembly 30 can be integrally formed together to form a single structure that can be formed from a single material or multiple materials. Alternatively, each component of the barrel assembly 30 can be separate components that are coupled together or some components can be integrally formed together to form a single structure that is coupled together with other components.

[0041] In operation, the inner barrel 34 can be filled with a first fluid through the barrel outlet 40. In particular, a fill tube (not shown) can be inserted into the barrel outlet 40 and into the inner opening 58. As described above, the inner opening 58 is in fluid communication with the delivery tube portion 37 of the piston tube 36, which in turn is in fluid communication with the inner barrel 34. When the inner barrel 34 is in the position shown in FIG. 1, the vent path is open to atmosphere. In particular, in this position, as the inner barrel 34 is filled with the first fluid, air is pushed out of the back of the outer barrel 32. A barrel assembly having a vent path with a vent slot is described in U.S. Patent No. 7,506,783, the contents of which are incorporated herein by reference. Figure 3

[0042] At the same time that the inner barrel 34 is being filled with the first fluid, a force is applied to the piston tube 36 that pulls the piston tube 36 in a direction away from the flange 56. The force applied to the piston tube 36 includes, for example, the force of the first fluid on the inner barrel 34 and the frictional force between the lower seal 38 and the delivery tube 36 as the inner barrel 34 slides toward the distal end 27a of the outer barrel 32. It should be understood that the rear chamber 47 can be filled with the first fluid before the front chamber 45 is filled with the second fluid, or the rear chamber 47 and the front chamber 45 can be filled simultaneously. If the front chamber 45 is overfilled, the lower seal 38 can contact the upper seal 39, thereby applying additional force to the piston tube 36. The force applied by the lower seal 38 can be up to or exceed 625 pounds (e.g., the fill pressure in the front chamber 45 is 300 pounds per square inch). Each of the applied forces pulls the piston tube 36 away from the flange 56.

[0043] The cavity 78 extends from the cavity base 82 to the cavity opening 80 to an optimal distance to minimize the risk of the piston tube 36 being removed from the cavity 78 of the flange 56 during a fill operation. In one aspect, the distance between the cavity base 82 and the cavity opening 80 is at least 2.5 millimeters. Preferably, the distance between the cavity base 82 and the cavity opening 80 is at least 8 millimeters. The distance that the cavity 78 extends provides an additional length of interface between the extended end 57 of the piston tube 36 and the cavity 78, which provides increased retention of the piston tube 36 within the cavity 78, provides additional length for improved or additional retention interface features between the extended end 57 and the cavity 78, and provides the option to improve fluid flow through the barrel outlet 40 by increasing the size of the inner opening 58 and the outer opening 60.

[0044] ​The distance between the cavity base 82 and the cavity opening 80 can also be related to the diameter of the flange 56. For example, the distance between the cavity base 82 and the cavity opening 80 can be selected based on the diameter of the inner surface 79 of the inner flange wall 70. The inner surface 79 defines at least a portion of the cavity 78. In one aspect, the ratio between the distance from the cavity base 82 to the cavity opening 80 and the diameter of the inner surface 79 is greater than 0.19. In an alternative aspect, the ratio between the distance from the cavity base 82 to the cavity opening 80 and the diameter of the inner surface 79 is between 0.5 and 0.7. For example, if the diameter of the inner surface 79 is 10 millimeters, then the distance between the cavity base 82 and the cavity opening 80 should be between 5 millimeters and 7 millimeters. In a preferred aspect, the ratio between the distance from the cavity base 82 to the cavity opening 80 and the diameter of the inner surface 79 is between 0.6 and 0.65. In a further preferred aspect, the ratio between the distance from the cavity base 82 to the cavity opening 80 and the diameter of the inner surface 79 is 0.62.

[0045] Figure 8B A detailed cross-sectional view of the flange 56 is shown with the extended end 57 of the piston tube 36 positioned within the flange 56. The extended end 57 can include at least one sealing bead 98. The sealing bead 98 protrudes from the extended end 57 toward the flange 56. The sealing bead 98 can contact the inner flange wall 70, the outer flange wall 72, and / or the base flange wall 74. In one aspect, the sealing bead 98 can be positioned toward the distal end of the extended end 57. Contact between the sealing bead 98 and the flange 56 can substantially prevent mixing of the fluids in the front chamber 45 and the rear chamber 47.

[0046] Figure 9 A partially transparent view of the distal end 28a of the outer barrel 32 is shown. The flange 56 includes a translucent material, such as polypropylene. The translucent material can allow a person or vision system to at least partially see into the cavity 78 through the flange 56. The piston tube 36 can include an opaque material. The material of the piston tube 36 is a different color than the color of the flange 56. Further, it is preferred that the color of the material of the piston tube 36 is different than the color of the fluids within the chambers 45 and 47. A person or vision system located outside of the barrel assembly 30 can see the piston tube 36 within the cavity 78 when the extended end 57 of the piston tube 36 is positioned within the cavity 78. If the piston tube 36 is dislodged from the flange 56, a person or vision system located outside of the barrel assembly 30 can see the piston tube 36 dislodged. Observing the piston tube 36 within the barrel assembly 30 provides a quick method of assessing whether the barrel assembly 30 is completely intact without requiring more complex or invasive testing. It should be understood that other components of the outer barrel 32, including the base wall 33 and the barrel side wall 35, can include a translucent material.

[0047] In one aspect, the outer flange wall 72 and / or the base flange wall 74 can have a thin thickness. For example, the thickness of the outer flange wall 72 and the base flange wall 74 can be less than the thickness of the base wall 33 of the outer barrel 32. The thin thickness of the outer flange wall 72 and / or the base flange wall 74 can increase the visibility of the presence of the piston tube 36 within the cavity 78 to a human or visual system.

[0048] After filling the inner barrel 34 with the first fluid, the outer barrel 32 can be filled with a second fluid. The outer barrel 32 is filled through the barrel outlet 40 but not through the outer opening 60. After the inner barrel 34 and the outer barrel 32 are filled, a human or visual system can view the flange 56 to verify that the piston tube 36 has not fallen out of the outer barrel 32. A cap (not shown) can be used to close the barrel outlet 40 of the barrel assembly 30.

[0049] The fluid in the barrel assembly 30 can then be dispensed through the caulking gun 20 as shown in Figure 1 In operation, as the plunger 22 advances in the axial direction A toward the distal end 28 of the barrel assembly 30, the inner barrel 34 moves in the axial direction A toward the barrel outlet 40. As the inner barrel 34 advances in the axial direction A, the first fluid from the inner barrel 34 is forced through the flange channel 86, the inner opening 58, and the first flow channel 94 into the piston tube 36 and to the barrel outlet 40. As the inner barrel 34 advances in the axial direction A, the upper seal 38 advances in the axial direction A toward the barrel outlet 40. Initially, when the barrel assembly 30 is full, the upper seal 38 and the lower seal 39 are side by side. However, as the inner barrel 34 advances in the axial direction A, the inner barrel 34 pushes the upper seal 38 in the axial direction A, which forces the second fluid in the outer barrel 32 to be dispensed from the barrel outlet 40 through the outer opening 60 and the second flow channel 96.

[0050] It should be understood that the foregoing description provides examples of the disclosed systems and methods. However, it is contemplated that other implementations of the disclosure can deviate from the foregoing examples in details. All references to the disclosure or examples thereof are intended to reference the particular example discussion being discussed at that time, but is not intended to imply any limitation as to the scope of the disclosure more generally. All language suggesting that any feature is “preferred” or “desired” is intended to mean that there is a present preference or desire for such feature, but unless otherwise indicated does not completely preclude the feature from being excluded from the scope of the disclosure.

Claims

1. A dual fluid cartridge assembly comprising: an outer cartridge extending in an axial direction from a proximal end to a distal end, the outer cartridge comprising: a base wall having an inner edge, the base wall positioned toward the distal end of the outer cartridge; and a flange extending at least partially along the inner edge of the base wall and at least partially protruding in the axial direction from the base wall, the flange defining a cavity extending in the axial direction from a cavity opening to a cavity base, wherein the cavity base is distal from the base wall in the axial direction toward the distal end, the cavity opening is distal from the base wall in the axial direction toward the proximal end, and the flange defines a mating slot within the cavity; and a piston tube having an extension end positioned within the cavity, the extension end defining a circumferential slot that cooperates with the mating slot.

2. The dual fluid cartridge assembly of claim 1, wherein, the base wall has an outer edge, and the outer cartridge further comprises an outer wall extending from the outer edge of the base wall in a direction opposite the axial direction.

3. The dual fluid cartridge assembly of claim 2, wherein, the outer wall defines a channel, and wherein the piston tube is at least partially positioned within the channel.

4. The dual fluid cartridge assembly of claim 3, wherein, the flange comprises an inner flange wall, an outer flange wall, and a base flange wall connecting the inner flange wall to the outer flange wall, wherein the inner flange wall, the outer flange wall, and the base flange wall define the cavity within the flange.

5. The dual fluid cartridge assembly of claim 4, wherein, the inner flange wall has an inner flange surface defining a flange channel extending through the flange in the axial direction, wherein the flange channel is in fluid communication with the piston tube.

6. The dual fluid cartridge assembly of claim 1, wherein, the cavity further extends circumferentially about the axial direction.

7. The dual fluid cartridge assembly of claim 1, wherein, the cavity extends a distance of at least 2.5 millimeters from the cavity base to the cavity opening.

8. The dual fluid cartridge assembly of claim 1, wherein, a ratio between the distance from the cavity base to the cavity opening and a diameter of an inner surface of the flange is greater than 0.

19.

9. The dual fluid cartridge assembly of claim 1, wherein, the mating slot cooperates with the circumferential slot to form a snap clip between the flange and the piston tube.

10. The dual fluid cartridge assembly of claim 1, wherein, the base wall is distal from the cavity opening in the axial direction, and wherein the base wall extends in a radial direction inward from a cylindrical side wall of the outer cartridge.

11. The dual fluid cartridge assembly of claim 1, wherein, the flange comprises a translucent material such that the extension end of the piston tube positioned within the cavity is visible through the flange from a position external to the dual fluid cartridge assembly to allow determination of whether the piston tube is detached from the outer cartridge.

12. The dual fluid cartridge assembly of claim 11, wherein, the base wall comprises a translucent material.

13. The dual fluid cartridge assembly of claim 1, wherein, the flange has a thickness that is sufficiently thin such that the extension end of the piston tube positioned within the cavity is visible through the flange from a position external to the dual fluid cartridge assembly to allow determination of whether the piston tube is detached from the outer cartridge.

14. The dual fluid cartridge assembly of claim 1, wherein, the piston tube is constructed of a material having a first color, and the flange is constructed of a material having a second color that is different than the first color.

15. The dual fluid cartridge assembly of claim 14, wherein, the outer cartridge is configured to be filled with a fluid having a third color that is different than the first color.

16. The dual fluid cartridge assembly of claim 1, wherein, The outer barrel is coupled to or formed with a barrel outlet, and a shoulder of the barrel outlet is attached to the flange and to an axial shoulder extending from the base wall in the axial direction toward the distal end.

17. The dual fluid cartridge assembly of claim 16, wherein, The shoulder is angularly offset from the axial direction to form at least a partial conical shape.

18. The dual fluid cartridge assembly of claim 1, wherein, The outer barrel is coupled to or formed with a barrel outlet, and a shoulder of the barrel outlet is attached to the flange and directly to the base wall.

19. The dual fluid cartridge assembly of claim 18, wherein, The shoulder is angularly offset from the axial direction to form at least a partial conical shape.

20. A dual fluid barrel assembly comprising: an outer barrel for carrying a first fluid, the outer barrel extending in an axial direction from a proximal end to a distal end, the outer barrel comprising: a barrel-shaped outer wall defining a passageway, a base wall having an inner edge defining a barrel outlet, the base wall positioned toward the distal end of the outer barrel, and a flange extending at least partially along the inner edge of the base wall and at least partially projecting in the axial direction from the base wall, the flange defining a cavity extending in the axial direction from a cavity opening to a cavity base, wherein the cavity base is distal from the base wall in the axial direction toward the distal end, the cavity opening is distal from the base wall in the axial direction toward the proximal end, and the flange defines a mating slot within the cavity; an upper seal within the passageway, the upper seal configured to seal the first fluid in the outer barrel; an inner barrel for carrying a second fluid; and a piston tube having an extended end, the piston tube at least partially within the passageway and the extended end within the cavity, the piston tube configured to provide a fluid flow path from the inner barrel to the barrel outlet, the extended end defining a circumferential slot that cooperates with the mating slot.

Images