Abstract:
The present invention relates to an apparatus ( 100 ) for the storing and dispensing of products. In particular, the present invention relates to an apparatus ( 100 ) for the storing and dispensing of inter-reactive compounds wherein the inter-reactive compounds are efficiently mixed on extrusion or expulsion.

Description:
FIELD OF THE INVENTION 
   The present invention relates to apparatus for the storing and dispensing of products. In particular, the present invention relates to apparatus for the storing and dispensing of inter-reactive compounds wherein the inter-reactive compounds are efficiently mixed on extrusion or expulsion. 
   BACKGROUND OF THE INVENTION 
   Dispensing apparatus in the form of cartridges is well-known in the art. In many instances, it is necessary to mix at least two different compounds together. On mixing, the compounds may react and usually harden. This type of technology is commonly used in chemical anchors, adhesives, sealants, food processing and medical applications. 
   Previous dispensing apparatus which requires the mixing of different compounds usually comprises two or more separate moulded compartments i.e. cartridges. These moulded compartments each house respective compounds which are mixed on extrusion or expulsion through an orifice. Additionally previous types of dispensing apparatus have various limitations such as significant ‘tooling-up’ costs in machinery for making the separate moulded cartridges. The moulded cartridges are also usually supplied in predetermined sizes meaning that different dispensing apparatus and pressure guns are required for each different size of cartridge. Moreover, in these types of apparatus, usually at least two pistons are required to obtain the correct mix of different compounds, again further adding to the complexity and cost of such a device. 
   EP 0754633 relates to cartridge systems used in dispensing devices suitable for dispensing inter-reactive multi-component compositions. The system disclosed in EP 0754633 comprises a clip which is manually pulled out of a container so that a flexible cartridge containing two separated types of material extends beyond the nozzle of the dispensing device. The protruding end of the cartridge is then cut with a knife or a pair of scissors. On extruding said material, the different components are intended to be mixed. However, a number of problems exist with such a system. First of all, the clip is very difficult to pull out meaning that a pair of pliers is almost essential to pull the clip out. Furthermore, the use of a knife or scissors is dangerous to a user as a significant amount of pressure is required to cut the cartridge open. Moreover, on cutting the cartridge open, some of the material spills out which necessitates cleaning of the scissors/knife and/or cartridge end. 
   It is an object of at least one aspect of the present invention to obviate or mitigate at least one or more of the aforementioned problems. 
   It is a further object of at least one aspect of the present invention to provide dispensing apparatus which is easy to use. 
   It is a yet further object of at least one aspect of the present invention to provide a container for products which can then be used to dispense the product in a simple and effective manner. 
   A further object of at least one aspect of the present invention is to provide a container for a multi-part chemical product which allows the component parts to be kept separate for storage purposes, but then allows the component parts to be brought together when required for use. 
   It is a yet further object of at least one aspect of the present invention to provide apparatus for storing products which can also be used for accurate dispensing of the products when required. 
   SUMMARY OF THE INVENTION 
   According to a first aspect of the present invention there is provided apparatus for storing and dispensing a product, the apparatus comprising: 
   a cartridge; and 
   a substantially rigid outer casing; 
   wherein the substantially rigid outer casing is adapted to receive the cartridge and the cartridge comprises a weakened area capable of rupturing when pressure is applied to the cartridge. 
   On rupturing of the weakened area, the total content(s) of the cartridge is (are) dispensed. 
   The cartridge may be ‘sausage-like’ in shape and may be formed in any suitable extrusion apparatus such as an adapted edible sausage making apparatus. 
   The cartridge may be made from thin, flexible film with a high tear strength. The cartridge may be made from any suitable plastics material such as polyethylene. Alternatively, the cartridge may be made from a metal/alloy foil. 
   Typically, the material forming the cartridge is not too elastic. If the material is too elastic, the apparatus will not function properly. 
   The material forming the cartridge may also be chosen so that it does not react and/or deteriorate on contact with the contained compounds. 
   Typically, the cartridge may comprise a plurality of separate chambers and, in particular, at least two chambers. The different chambers may contain different compounds which are intended to be mixed. The chambers may be of different volumes and may therefore contain different amounts of the different compounds. For example, the volume in a first chamber may be 40% of the whole cartridge and the second chamber may be 60% of the whole cartridge; the volume in the first chamber may be 20% of the whole cartridge and the volume in the second chamber may be 80% of the whole cartridge; and the volume in the first chamber may be 10% of the whole cartridge and the volume in the second chamber may be 90% of the whole cartridge. 
   Conveniently, on initial formation, the cartridge may have two open ends. Once the compound or compounds are extruded into the chamber or separate chambers of the cartridge, the ends of the cartridge may be sealed with any suitable sealing means. The seal for the end of the cartridge which is intended to rupture may be made weaker than a seal at the other end of the cartridge. The sealing means may comprise a sealing clip which may be releasable under pressure. Alternatively, any other suitable sealing means such as crimping, gluing, heat sealing or any form of cap or tie may also be used. 
   Preferably, on release of the sealing means different contents of the cartridge may mix substantially simultaneously together. This occurs as the single sealing means, seals all the contents of the cartridge. The mixing may occur immediately meaning that an efficient mix may be obtained. 
   Preferably, the substantially rigid outer casing may be a hollow cylindrical member made from any suitable plastics, metal or alloy material. The outer casing may have an inner cylindrical section which may be of constant diameter from one end to the other. Alternatively, the cylindrical member at one end may have a reduced diameter. 
   Typically, the outer casing is adapted to receive the cartridge and form a snug fit with the outer walls of the cartridge. The distance between the outer casing and the cartridge may be about 1-10 mm or preferably about 5 mm. This may prevent radial expansion (i.e. widening) on application of pressure to an end of the cartridge. 
   Conveniently, pressure may be applied to one end of the flexible cartridge by any suitable means such as any type of dispensing gun. The pressure may be applied manually or via a pneumatic piston. Typically, the dispensing gun may be a standard mastic gun as found in many DIY stores. Alternatively, any type of syringe like plunger or screw like plunger may be used. 
   Conveniently, there may be an expansion chamber into which the cartridge may partially expand into. The apparatus may be adapted so that on application of pressure to one end of the cartridge, expansion in the axial direction is prevented so that at the opposite end to which the pressure is applied, the cartridge deforms into an initial bulbous conformation. 
   Preferably, the outer casing comprises integral reaction shoulders which abut and prevent the cartridge from moving further along the longitudinal length of the outer casing as pressure is applied. The reaction shoulders may be adapted to the shape of the cartridge and may be substantially concave. The actual surface contact area between the reaction shoulder and the cartridge may be specifically chosen. If there is too much surface contact between the reaction shoulder and the cartridge, too much pressure will need to be applied to remove the sealing means from the cartridge and the material forming the cartridge may rupture at any specific point meaning that different compounds in different chambers may not mix. Alternatively, if there is too little surface contact between the reaction shoulders and the cartridge, the cartridge will be pushed through the outer casing without the sealing means rupturing. 
   In an alternative embodiment, the reaction shoulder may be formed from a separate insert which may be inserted into the outer casing. In a yet further alternative, the cartridge may be glued to the side of the outer casing thereby preventing movement along the length of the outer casing. 
   Typically, the expansion chamber may be integrally formed in the outer casing during initial moulding. Alternatively, the expansion chamber may be formed by a separate adaptor unit which may be placed into the outer casing. In a further alternative, the expansion chamber may be contained within a separate nozzle member. 
   Conveniently, the apparatus comprises a nozzle member which may be fitted to an end of the outer casing via, for example, a screw thread. The nozzle may comprise an integral mixer unit which further aids the mixing of the different products in the flexible cartridge. Alternatively, the mixer unit may be a separate item and may be inserted into the nozzle. Preferably, the diameter of the nozzle is wide enough to prevent blockage on release of the sealing means. 
   The nozzle may also comprise means for catching the sealing means such as a cross-member. The cross-member may be attached to the mixer unit or may be integrally formed at the entrance to the nozzle. 
   Preferably, the sealing means may be formed from any metal or plastics material such as soft aluminium or steel wire which is wound round the ends of the cartridge. The sealing means is not attached too tightly or too strongly as this will prevent the release of the sealing means on application of pressure to the cartridge. It is also preferred that any sharp ends formed by the sealing means may be pointed away from the flexible cartridge thereby preventing any possible piercing of the cartridge. 
   An advantage of the apparatus is that once the contents of the cartridge are emptied, the emptied cartridge may be removed and replaced with a new cartridge. The apparatus may therefore be reusable. The emptied cartridge may be removed by simply detaching the pressure gun from the cartridge. To facilitate the removal of the emptied cartridge, the outer casing may have a hinged opening to allow a user easy entry. 
   Preferably, the film forming the cartridge is adapted so that on expansion into the expansion chamber, the film extends part way into the expansion chamber. This may prevent mixing of different compounds and may therefore prevent any hardening of mixed materials within the apparatus. This may allow the apparatus to be used at a later date without completely emptying the contents of the cartridge. 
   Typically, the apparatus may be used to provide dispensed products for use in chemical anchors, sealants, food processing and medical applications. Uses of chemical anchors includes securing bolts in concrete/masonry, forming a stud socket and post-installed rebar connections. 
   Compounds which are intended to be mixed may include any suitable resins, epoxies, polyesters and vinyl esters. 
   According to a second aspect of the present invention, there is a provided a method for dispensing a product, the method comprising: 
   inserting a cartridge which comprises a weakened area into a substantially rigid outer casing which is adapted to receive the cartridge; and 
   applying pressure to the cartridge thereby increasing the pressure within the cartridge to a point where said weakened area ruptures enabling the contents of the cartridge to be dispensed. 
   Typically, the cartridge comprises a plurality of chambers containing different compounds. 
   Preferably, on rupturing of the weakened area, different compounds in the cartridge may be simultaneously mixed. 
   According to a third aspect of the present invention, there is provided a kit comprising: 
   a cartridge comprising at least one weakened area capable of rupturing on application of pressure to the cartridge; 
   a substantially rigid outer casing which is adapted to receive the cartridge; and 
   a dispensing gun. 
   Preferably, the dispensing gun is a standard mastic gun. 
   Preferably, the kit may be used to simultaneously mix different compounds. 
   According to a fourth aspect of the present invention there is provided a cartridge which comprises at least one weakened area capable of rupturing when pressure is applied to the cartridge and wherein the cartridge comprises at least two separate chambers containing different materials which are dispensable on application of pressure. 
   Typically, on rupturing of the weakened area the materials in the separate chambers may simultaneously mix with one another. 
   Conveniently, the cartridge is made from thin, flexible film with a high tear strength. 
   Typically, the cartridge is ‘sausage-like’ in shape. 
   According to a fifth aspect of the present invention, there is provided use of a kit according to the fourth aspect for dispensing a product. 
   According to a sixth aspect of the present invention, there is provided apparatus for storing and distributing a product, comprising a container which has at least one weakened area that will rupture when pressure is applied to the container. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: 
       FIGS. 1A ,  1 B and  1 C are schematic representations of dispensing apparatus according to a first embodiment of the present invention; 
       FIGS. 2A-2E  are schematic representations of the operation of dispensing apparatus according to a second embodiment of the present invention; 
       FIGS. 3A-3C  are schematic representations of dispensing apparatus according to a third embodiment of the present invention; 
       FIGS. 4A and 4B  are schematic representations of dispensing apparatus according to a fourth embodiment of the present invention; 
       FIGS. 5A and 5B  are schematic representations of dispensing apparatus according to a fifth embodiment of the present invention; 
       FIGS. 6A and 6B  are schematic representations of dispensing apparatus according to a sixth embodiment of the present invention; 
       FIGS. 7A and 7B  are schematic representations of a mixing element according to an embodiment of the present invention; 
       FIGS. 8A and 8B  are schematic representations of a further mixing element according to an embodiment of the present invention; 
       FIGS. 9A-9C  are schematic representations of different casings according to the present invention; and 
       FIG. 10  is a schematic representation of the length of film extending beyond a clip. 
   

   DETAILED DESCRIPTION 
   Referring to  FIGS. 1A and 1B , there are schematic representations of dispensing apparatus, generally designated  100 . The apparatus  100  comprises a substantially rigid cylindrical hollow casing  102 . The inner surface  104  of the casing  102  has a substantially tubular section which forms a wide opening  106  at a first end of the casing  102  and a narrower opening  108  at a second end of the casing  102 . Towards the second end of the casing  102 , the diameter of the inner surface  104  of the casing  102  narrows, firstly via a shoulder  110 , which then extends for a period along a reduced diameter section  112 . There is then a further reduction in the diameter via a chamfered surface  114  to a final reduced diameter tubular section  116 . The region of the casing  102  extending between the shoulder  110  and the narrow opening may be termed an expansion chamber  117 . It is appreciated that the expansion chamber is proximate to and in communication with the narrow opening. On the outer surface of tubular section  116  there is a screw thread  118 . The cylindrical casing  102  is made from any suitable plastics or metal/alloy material. 
   As shown in  FIG. 1A , the cylindrical casing  102  is used to snugly receive a cartridge  120  which may be described as being ‘sausage-like’ in shape. The cartridge  120  comprises two separate chambers  122 ,  124  which are secured to one another via adhesive means in the ‘sausage-like’ configuration. Chamber  122  contains compound A and chamber  124  contains compound B. The chambers  122 ,  124  are sealed separate units. 
   The chambers  122 ,  124  are formed from a thin material which has a limited degree of flexibility. However, the material is not too elastic otherwise the material will simply stretch on application of pressure. The material also has a high tear strength to prevent the cartridge  120  from inadvertently bursting open. The material is also specifically chosen so as to be inert towards the materials which they contain. The material may be made from any suitable plastics, polymer or metal foil material. 
   The ends of the cartridge  120  are closed with clips  126  once compounds A and B have been inserted into their respective chambers  122 ,  124 . Any suitable type of apparatus is used to form the ‘sausage-like’ cartridge  120 . For example, edible sausage making apparatus may be used. Clips  126  are formed from relatively soft aluminium wire and are wound around the ends of the chambers  122 ,  124  to prevent any leakage of compounds A and B during storage or initial placement in the casing  102 . Careful attachment of the clips  126  is required so that any sharp ends formed by the clips  126  do not pierce the cartridge at any time during use of the dispensing apparatus  100 . 
   A compressing back plate  128  is also shown in  FIGS. 1A and 1B  which has a concave surface  130  adapted to engage with the cartridge  120 . 
   The compressing back plate  128  comprises a central recess  129  which clip  126  inserts into on engagement with the back plate  128 . 
     FIGS. 1A and 1B  also show that the apparatus comprises a mixing nozzle, generally designated  132 . The mixing nozzle  132  has an opening  134 . Around the opening  134  there is a thread  136  which is adapted to screw onto thread  118  on the casing  102 . The mixing nozzle  132  has an integral spiral chamber  138  which aids in the mixing of compounds A and B. 
     FIG. 1A  shows that the cartridge  120  is tightly secured within the casing  102 . It is important to appreciate that the sides of the cartridge  120  are close to or abut against the inside surface  104  of the casing  102 , therefore restricting any form of axial displacement. Furthermore, the cartridge  120  engages against shoulder  110  and prevents the cartridge  120  from travelling any further along the casing  102 . 
     FIG. 1C  shows the apparatus as illustrated in  FIGS. 1A and 1B  attached to a dispensing gun  180 . 
     FIGS. 2A-2E  represent a casing  202  according to a second embodiment of the present invention. Similar reference numerals to that used in  FIGS. 1A and 1B  are used but have the prefix “2”. The container  202  is similar to the casing  102  in  FIGS. 1A and 1B , apart from the fact that there is a difference in the surface  214  in the casing  102  which reduces the diameter of the inner surface  204  of the casing  102 . Surface  214  reduces the diameter in a smoother concave manner, minimising any sharp edges which may pierce the cartridge  220 . 
     FIGS. 2A-2E  progressively show the effect on the cartridge  220  as pressure is applied to one end. The pressure is applied by a mastic gun (not shown). In  FIG. 2D  it is clear that the cartridge  220  comprising separate chambers  222 ,  224  fills expansion chamber  217  at the end of the container  202  and abuts the inner surface  204  of the casing  202 . It should also be appreciated that shoulders  210  prevent the cartridge  220  from merely being pushed along the container  202 . The inner surface  204  of the hollow casing  202  also prevents the cartridge  220  from merely expanding axially. On application of pressure to the cartridge  220 , the unsupported end of the cartridge  220  expands into a bulbous form into expansion chamber  217  as shown in  FIGS. 2B and 2C  and eventually completely fills the expansion chamber  217 , as shown in  FIG. 2D . 
   On application of further pressure, the hydrostatic pressure inside the cartridge  220  eventually forces the clip  226  off, as shown in  FIG. 2E . 
   As shown in  FIG. 2E , the film of the cartridge  220  extends part way along the narrowest section of the casing  202  which helps to prevent any hardening of material therein. 
   On removal of the clip  226 , compounds A and B within the separate chambers  222 ,  224  are free to be extruded on application of further pressure from a mastic gun. 
   Furthermore, on release of clip  226 , compounds A and B are released substantially simultaneously enabling the different compounds to efficiently mix. 
     FIGS. 3A-3C  show a third embodiment of the present invention. Once again, reference signs similar to that previously used are utilised with the prefix “3”. Side surfaces  314  are concave shaped to support the cartridge  320  as pressure is applied from a mastic gun. The cartridge  320  fills the expansion chamber  317  at the end of the container  302 .  FIG. 3C  shows the clip  326  being forced off due to the increased pressure, with the minimum length between a nozzle and the film being shown which prevents hardening and blockage of compounds A and B if extrusion of the material is stopped at any time. 
     FIGS. 4A and 4B  represent a fourth embodiment of the present invention. Reference signs similar to those previously used are utilised with the prefix “4”. In  FIG. 4B , the cartridge  420  is shown within the casing  402 . In this embodiment, the casing  402  simply comprises an extended tubular section  404  of uniform diameter. There is therefore no expansion chamber in the casing  402  on insertion of the cartridge  420 . However, as shown in  FIGS. 4A and 4B , the mixing nozzle  432  comprises an expansion chamber  417  via which the cartridge  420  may expand into on application of pressure to the opposite end. The container  402  has shoulders  410  which prevent the cartridge  420  from being longitudinally displaced on application of pressure. Additionally, the container  402  prevents axial displacement of the cartridge  420  on application of pressure. The cartridge  420  will therefore expand into expansion chamber  417 . Eventually, as discussed previously, clip  426  will release once a specific internal hydrostatic pressure is obtained for the container  420 . 
     FIGS. 5A and 5B  show a fifth embodiment. Similar reference signs to those used previously are used with the prefix “5”. In this embodiment, a standard cylindrical hollow casing  502  is used which has a substantially uniform internal diameter. To create an expansion chamber  517  for the cartridge  520  to expand into, an adaptor  540  is inserted into the casing  502 , as shown in  FIG. 5A . The adaptor  540  comprises a shoulder  510  which prevents longitudinal movement of the cartridge  520 . A reduced circumference section  512  and an additional surface  514  further reduces the diameter of casing  502 . The operation of the cartridge  502  generally is the same as that previously described. 
     FIGS. 6A and 6B  represent dispensing apparatus, generally designated  600  which is substantially similar to that described previously. The reference numerals have the prefix “6”. The difference in dispensing apparatus  600  is that there is a nozzle adaptor  650  which is attachable to the container  602 . This allows a range of mixing nozzles  632  to be used enabling different flows of material to be obtained. 
   In the present invention, there is the potential problem that the clip used to retain the different compounds in their respective chambers may block the extrusion of the compounds. To overcome this problem, means of catching the clip may be deployed. 
   The embodiment shown in  FIGS. 7A and 7B  comprises a cross member  762  at one end of mixing element  760 . As shown in  FIG. 7B , on release of the clip  726 , the cross member  762  prevents the clip  726  from entering the main body of mixing nozzle  732 . 
     FIGS. 8A and 8B  represent a further embodiment wherein mixing nozzle  832  comprises a cross-section  862  which will once again catch a clip  826  before it enters the main body of mixing nozzle  832 . 
   While specific embodiments of the invention have been described above, it will be appreciated that departures from the described embodiments may still fall within the scope of the invention. For example, there may be any number of different chambers and the cartridges may be of any suitable size. Additionally, any type of sealing means may be used to close the ends of the chambers. Furthermore, the sealing means may be attached relatively loosely meaning that only a minimum amount of pressure needs to be applied to force the sealing means off the cartridge. 
   EXAMPLES 
   Example 1 
     FIGS. 9A-9C  represent different lengths of film extending beyond a clip. The embodiments shown in  FIGS. 9A and 9B  will require too high a pressure to force the clip off the casing.  FIG. 9C  represents more of a preferred embodiment with the film extending a relatively small distance beyond the clip. 
     FIG. 10  defines the distance which the film extends beyond the clip by reference symbol ‘A’. Table 1 below shows that the clip only comes off when the film extends 4 mm or 2.5 mm beyond the clip. 
   
     
       
             
             
             
           
             
             
             
           
         
             
               TABLE 1 
             
             
                 
             
             
               Test 
               A (mm) 
               Burst Mode 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
               1 
               10 
               Film 
             
             
               2 
               11 
               Film 
             
             
               3 
               11 
               Film 
             
             
               4 
               10.5 
               Film 
             
             
               5 
               8 
               Film 
             
             
               6 
               7.5 
               Film 
             
             
               7 
               6 
               Film 
             
             
               8 
               5 
               Film 
             
             
               9 
               4 
               Clip 
             
             
               10 
               2.5 
               Clip