Cartridge

Abstract

 A cartridge arrangement (10) comprises a frangible portion (12) and a guide tube (14). The frangible portion (12) being substantially housed within the guide tube (14) with an end (22) of the frangible portion (12) being seated by a clip (24). A cap (16) attaches to an end of the guide tube (14) by a screw thread. Unscrewing of the cap (16) urges arms (50,52), having a portion seated behind the clip (24), away from the guide tube (14) thereby opening the frangible portion (12).

Description

[0001] This invention relates to a cartridge.

[0002] Cartridges comprising a bag like flexible membrane housed within a rigid body are known to those skilled in the art, see for example European Patent No. 0 754 633 and European Patent Application No. 04 714 857.2.

[0003] Typically, such a cartridge is used in standard caulking gun. This allows the contents of the cartridge to be applied in a controlled manner.

[0004] The closure of the flexible membrane in order to retain the cartridges contents within it represents a particular difficulty. European Patent Application No. 04 714 857.2 discloses an arrangement where a staple is wound around an open end of a flexible membrane to close the membrane. The action of caulking gun piston on an opposite end of the membrane forces the membrane's contents past the staple, thereby opening the membrane.

[0005] Such an arrangement has a number of disadvantages. Firstly, it is necessary to provide a weakened staple compared to conventional staple arrangements. This weakening of the staple decreases the resistance of the closure to leakage of the membrane's contents.

[0006] Also, the reliance on the indirect pressure of the piston to force the staple open results in a low reliability of opening.

[0007] European Patent No. 0 754 633 discloses an arrangement whereby a length of membrane is pulled through a neck of a rigid body of a cartridge and has a clip attached to it. The clip is sufficiently wide to prevent the passage of the membrane back through the neck.

[0008] This arrangement requires the cutting of the membrane in order to allow the membrane's contents to flow out of the cartridge.

[0009] According to a first aspect of the present invention there is provided a cartridge arrangement comprising a frangible portion, the frangible portion being substantially housed within a guide tube, an end of the frangible portion being sealed by sealing means, characterised by engagement means arranged to engage the sealing means such that motion of the engagement means away from the guide tube urges the sealing means away from the frangible portion.

[0010] This arrangement simplifies the opening of a cartridge by reducing the number of steps requires to open a cartridge, preferably to a single step.

[0011] The use of engagement means allows the use of a non-weakened sealing means. This reduces leakage of the contents of the cartridge.

[0012] Additionally, the engagement means provide a reliable means of opening the internal portion of the cartridge. This provides increased reliability of opening of the cartridge over prior art arrangements due to the direct linkage of the engagement means with the sealing means.

[0013] Such an arrangement does not require the cutting of the internal portion of the cartridge to release its contents. This increases the ease of operation of the cartridge over prior art arrangements.

[0014] The engagement means may comprise a resilient member having at least one projection arranged to abut the sealing means. The engagement means may be fabricated from a plastics material.

[0015] The engagement means may comprise a cap arranged to attach to an end of the guide tube. The cap may be arranged to engage the guide tube by means of a screw thread.

[0016] The engagement means may comprise a locking plate located between an end of the cap and a head of the engagement means.

[0017] The engagement means may comprise arms having a portion shaped such that they are complementarily curved to the curvature of a section of the cap.

[0018] This allows the rotation of the cap when screwing and unscrewing the cap without imparting rotational motion to the arms. This reduces the chance of slippage of the arms over the cartridge.

[0019] A portion of the engagement means may be arranged to locate within a neck of the guide tube. Alternatively, a portion of the engagement means may be arranged to locate within a body of the guide tube.

[0020] These two alternative arrangements allow for the use the invention with partially full and full cartridges

[0021] The sealing means may comprise a staple or a clip.

[0022] The present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a cross section of a dispensing device comprising a cartridge arrangement according to the present invention.

[0023] Referring now to Figure 1, a dispensing device 10 comprises a frangible cartridge 12, a guide tube 14 and a cap 16.

[0024] The frangible cartridge 12 comprises two compartments 18, 20. Each compartment 18,20 contains a respective component to be dispensed. The components are typically fluids or semi-solid components. A free end 22 of the cartridge 12 is sealed with a closure 24, typically a ring staple or a clip. Typically, the cartridge 12 is fabricated from a flexible, pliable material, usually a plastics material.

[0025] The guide tube 14 comprises a hollow cylindrical body 26 and a nozzle adaptor 28. The nozzle adaptor 28 comprises a central hollow cylindrical bore 30, a shoulder portion 32 and a neck 34. The exterior of the neck 34 has a thread 36 provided over a region of its external surface.

[0026] The guide tube 14 receives the cartridge 12 such that the free end 22 passes into the neck 34. In some embodiments the free end 22 will pass through the neck 34 such that the closure locates externally of the neck 34.

[0027] The cap 16 comprises a cylindrical body portion 36 and an inwardly tapering, open ended frustoconical head section 38. The body portion 36 is comprises an internal thread 40, which is complementarily threaded to the external thread 36 of the neck 34.

[0028] A jaw arrangement 42 that is locatable within the cap 16 comprises a pair of opposed arms 44a,b. Each of the arms 44a,b comprises a flared head 46, a waist 48, a curved shoulder 50, a leg 52 and a foot 54.

[0029] The arms 44a,b are positioned such that the respective feet 54 locate behind and, in a preferred embodiment, abut the closure 24 remote from the free end 22. The cap 16 threads on to the neck 34 such that the respective flared heads 46 project through the open end of the head section 38, and reside externally of the cap 16.

[0030] The respective waists 48 pass partially through the opening of the head section 38, with the remainder residing in the opening. The shoulders 50 are chamfered such that they abut an internal surface of the head section 38. The legs 52 project towards the open end of the body portion 36, forming an L-shape with a terminal end face of the shoulder 50. The foot 54 projects inwardly towards the central axis of the cap 16.

[0031] A C-shaped plate 56 is fitted around the waists 48 between the heads 46 and the head section 38 of the cap 16. Typically, the plate 56 is shaped such that it fits around the waists 48 snugly and abuts both undersides of the heads 46 and an outer annular surface of the head section 38.

[0032] In order to open the cartridge a user unscrews the cap 16 from the neck 34. Usually, the shoulders 50 are shaped such that they are complementarily curved to the curvature of the internal surface of the head section 38. This allows the cap 16 to be unscrewed without rotation of the arm 44a,b. As the cap 16 is unscrewed the plate 56 engages the heads 46 of the arms 44a,b and urges them away from the guide tube 14. As the feet 54 engage the closure 24 the closure 24 moves in sympathy with the arms 44a,b and slides over the cartridge 12 towards its free end 22.

[0033] As the unscrewing of the cap 16 progresses the closure 24 will pass over the free end 22 of the cartridge 12. This results in the opening of the cartridge 12.

[0034] It will be appreciated that although described with reference to a compartment cartridge the present invention is applicable to single compartment cartridges and also cartridges having more than two compartments.

[0035] It will be further appreciated that although described with reference to an arrangement wherein the closure is located within the neck of the guide tube the closure may be located within the body of the guide tube. In such an arrangement the arms of the jaw arrangement must be longer than in the present embodiment.

[0036] In a further embodiment, not shown, an L-shaped catch is inserted into the neck of the guide tube, the short arm of which engages behind the closure. The closure can then be levered free of the cartridge, thereby opening the cartridge. It will be appreciated that the catch may be inserted into the neck manually, or it may depend from the cap.

Claims

1. A cartridge arrangement (10) comprising a frangible portion (14), the frangible portion (14) being substantially housed within a guide tube (12), an end (22) of the frangible portion (14) being sealed by sealing means (24), characterised by engagement means (42) arranged to engage the sealing means (24) such that motion of the engagement means (42) away from the guide tube (12) urges the sealing means (24) away from the frangible portion (14).

2. A cartridge arrangement according to claim 1 wherein the engagement means (42) comprises a resilient member (44a,44b) having at least one projection (54) arranged to abut the sealing means (24).

3. A cartridge arrangement according to either claim 1 or claim 2 wherein the engagement means (42) is fabricated from a plastics material.

4. A cartridge arrangement according to any preceding claim wherein the engagement means (42) comprises a cap (16) arranged to attach to an end of the guide tube.

5. A cartridge arrangement according to claim 4 wherein the cap (16) is arranged to engage the guide tube (14) by means of a screw thread (36,40).

6. A cartridge arrangement according to claim 5 wherein unscrewing of the cap (16) when engaged is arranged to urge the sealing means (24) away from the guide tube (14).

7. A cartridge arrangement according to any one of claims 4 to 6 wherein the engagement means (42) comprises a locking plate (56) located between an end of the cap (16) and a head of the engagement means (42).

8. A cartridge arrangement according to any preceding claim wherein the engagement means (42) comprises arms (50,52) having a portion shaped such that they are complementarily curved to the curvature of a section of the cap (16).

9. A cartridge arrangement according to any preceding claim wherein a portion of the engagement means (42) is arranged to locate within a neck of the guide tube (14).

10. A cartridge arrangement according to any one of claims 1 to 8 wherein a portion of the engagement means (42) is arranged to locate within a body of the guide tube (14).

11. A cartridge arrangement according to any preceding claim wherein the sealing means (24) comprises a staple or a clip.

Drawing