Dispensing machine

Abstract: A machine which dispenses beverages from sachets containing a beverage-producing material (such sachets as described in EP-A-0179641) injects liquid into the sachet. A pressure-sensitive base seam of the sachet is opened by liquid pressure. To prevent the base seam opening explosively and spray solids or liquid away from the beverage receptacle directly below the sachet, a heat source is employed to weaken the seam prior to opening, so that it opens non-explosively by peeling in a controlled manner. The heat source can be internal (an initial volume of hot liquid at a pressure insufficient to break the seal) or external such as a radiant source, hot air or steam. Such a machine is particularly advantageous for dispensing hot chocolate.

Description: The present invention relates in general to the field of beverage dispensing machines, and in particular, in one embodiment, to hot drinks dispensing machines which utilise sachets of beverage-producing material through which a hot liquid passes. Prior art beverage dispensing machines which utilise packages of beverage-producing material are well known. In one variation of such known machines, they include a tank of hot water communicating with a water injector in the form of a hollow needle. A sachet of beverage-producing material is inserted into the machine by the user, the injector of the machine pierces a plastics nozzle carried in the top seam of the sachet and hot water is introduced into the sachet. The beverage is dispensed from the machine through the bottom of the sachet. The bottom seam of the sachet is secured by a pressure-sensitive adhesive. This seal is forced open by the pressure of fluid in the sachet. The beverage itself is formed by the hot water mixing with the beverage-producing material as it passes through the sachet. Such a system has been marketed by us, initially under the trade mark "Dimension 3", now "Flavia". Sachets and machines are described, for example, in EP-A-0179641 and GB-A-2122881, respectively. In general, ground coffee or leaf tea is supported upon filter material within the sachets. This arrangement ensures that when the bottom of the sachet opens due to the pressure of hot water in the sachet, the tea leaves or coffee grains are not forced out of the sachet and into the receptacle in which the beverage itself is being collected. Sometimes, however, the opening of the sachet is so explosive and vigorous that a small amount of beverage is sprayed from the bottom of the sachet away from the receptacle below the sachet so that not all of the beverage enters the receptacle. This is clearly undesirable. Although the aforementioned prior art dispensing machines work satisfactorily when producing coffee or tea, subject to any initial spraying of the beverage as the sachet opens being inexcessive, the machines are less satisfactory for dispensing certain other beverages, such as hot chocolate. Hot chocolate, for example, is formed by dispersing a powder in a liquid rather than using an infusion technique as in the case of coffee or tea. Accordingly, the hot chocolate powder must be able to pass out of the sachet as the beverage is produced. If a prior art machine is used, this results in the powder as well as the liquid being sprayed out of the bottom of the sachet as the sachet opens explosively. This powder is wasted and causes a mess. Powder can also be ejected into the receptacle insufficiently dispersed in the hot liquid. In another known variation of machines which produce beverages from packages with pressure-sensitive seals, a sachet with such a seal is compressed externally to rupture the seal and express the sachet contents into a waiting receptacle. Such sachets have typically contained fruit juice or cola concentrates, which are mixed with liquid (typically water-gaseous or non-gaseous as the case may be) dispensed separately into the receptacle. If the sachet opens explosively, as with the first-mentioned version of machines, the expelled product can be ejected vigorously - which is less than satisfactory. The present invention has been devised to overcome the problem of spraying beverage (in the case of tea or coffee) or beverage liquid or powder (in the case of hot chocolate, liquid concentrates and the like) when the bottom of a package used in a beverage dispensing machine is forced open by the pressure increase within the package itself. The present invention resides in the use of an external heating means which heats the pressure-sensitive seal of the package when it is positioned in the dispensing machine, such that the adhesive strength of the seal is reduced to enable the bottom of the package to open more easily and smoothly. In this way, the package does not open explosively. A further advantage of this invention is that the opening places less stress on the package, thus reducing the likelihood of other seams in the package rupturing unwantedly. According to the present invention there is provided a beverage dispensing machine as specified in claim 1 hereinafter. Beverage dispensing machines that employ sachets or cartridges which have a seal opened in use are described, for example, in FR-A-1,371,186; EP-A-250,810; GB-A-2,215,189; and CH-A-271,335. There is no disclosure in these documents of the problem of pressure-sensitive seals opening explosively nor of the solution provided by this invention: the use of an external means of heat supply to weaken the pressure-sensitive seal. The external heat source may be provided by a radiant source such as a hot wire or a halogen bulb, a hot air blower or any other suitable means. When an external heat source is employed, the liquid injected into the package need not necessarily be hot itself. The invention can thus be employed for providing cold beverages. In another preferred embodiment of the invention, the machine includes a tank for hot water, and in use steam from the tank is used to heat and hence weaken the seal at the bottom of the package. Preferably an activator triggers the heat supply when a package is inserted in the machine. It is also preferable that the heat supply is only activated for a preset time period and is then deactivated. It will of course be appreciated that any form of external heat supply could be used to heat the seal at the bottom of a sachet in the machine, and hence reduce the adhesive strength of the seal so that the sachet does not explode open when the hot liquid is pumped into the sachet from above. In a further embodiment, the pressure increasing means is a means for compressing the package externally, such as a piston or one or a pair of rollers which squeeze the package. The beverage-producing product in the package may be an infusion material such as ground coffee or leaf tea, a solid to be dispersed in liquid such as chocolate powder or soup powder, or a liquid such as a fruit juice or cola concentrate. It may constitute just one component or precursor of the final beverage, or it may constitute the complete beverage itself. Specific embodiments of the present invention are now described purely by way of example with specific reference to the type of machines dispensing beverages from sachets with nozzles, as described in EP-A-0179641 and GB-A-2122881 mentioned above. A beverage dispensing machine according to the present invention includes a tank for containing hot water, a water injector connected to the tank, a pump, and a control means for coordinating the flow of water from the tank through the injector. On insertion of a sachet containing an infusion-type beverage-providing material, an activator is triggered which instructs the control means to deliver a preset quantity of hot water to the sachet in separate preset volumes. Firstly, however, the injector is lowered and pierces the plastics nozzle of the sachet to enter the sachet itself. An external heat source is provided in the beverage dispensing machine at a position where heat can be readily applied to the bottom seal of a sachet inserted in the machine. The heat source is either a hot wire, a hot air blower or a halogen bulb. Alternatively, a supply of steam from the hot water tank could also be used. On insertion of a sachet into the machine, an activator initiates power to the heat source which heats the seal at the bottom of the sachet and hence reduces the adhesive strength of the seal. Hot water is introduced into the sachet. After a predetermined period of time, sufficient water has been introduced into the sachet to pressurise the bottom seal of the sachet which then peels opens due to the reduction in adhesive strength of the seal. At this time, the heat source is de-activated. It will of course be understood that the present invention has been described above purely by way of example, and that modifications in detail can be made within the scope of the invention as claimed.

Claims: A beverage dispensing machine comprising means for receiving a package containing a beverage-producing product, means for increasing the pressure within the package so that the inside pressure is greater than the outside pressure to cause a pressure-sensitive seal of the package to rupture and enable material from the package to be released to assist in forming, or to form, a beverage, characterised in that said machine additionally comprises means for applying heat directly to the seal from outside the package to reduce the adhesive strength of the seal whereby the pressure required to open the seal is reduced and the seal opens non-explosively by peeling open in a controlled manner. A beverage dispensing machine according to claim 1, wherein said heat applying means comprises a hot wire, a halogen bulb or a hot air blower. A beverage dispensing machine according to claim 1, which includes a tank for hot water and wherein the heat applying means comprises means for applying steam from the tank to heat the pressure-sensitive seal. A beverage dispensing machine according to any one of claims 1 to 3, which comprises activator means for triggering the heat applying means when a package is inserted in the machine. A beverage dispensing machine according to claim 4, wherein the activator means is only activated for a preset time period and is then de-activated. A beverage dispensing machine according to claim 1 which additionally comprises liquid supply means for introducing liquid into the package, said liquid supply means constituting said pressure increasing means. A beverage dispensing machine according to claim 6 wherein said receiving means comprises means for receiving a nozzle of said package and wherein said liquid supply means is arranged to introduce liquid into the package through said nozzle.

Inventors: KINNA ROBERT NEIL, KINNA, ROBERT NEIL
Applicants: MARS G B LTD, MARS G.B. LIMITED
Application year: 1990
Main classification: A47J31
IPC codes: A47J31, B67D1