GB2165741A - Infusion apparatus - Google Patents

Abstract

Apparatus for making an infusion, e.g. tea or coffee, and including means (71, 78) for drawing a filter medium (70) under a container (50) when it is in an inoperative position and including a manually operable latch member (87) by operation of which the pinch rollers (78) can be lifted away from the drive roller (71) to permit a new length of filter medium (70) to be drawn under the container (50) and threaded between the rollers (71 and 78). <IMAGE>

Description

SPECIFICATION Infusion apparatus This invention relates to apparatus, hereinafter referred to as being of the type specified, for producing, during a cycle, an infusion from a liquid and an infusible ingredient, e.g. tea or coffee, and which comprises the following: 1. a containerfor receiving the ingredient and liquid and arranged to have a base in the form of strip filter medium which is permeableto air and liquid but substantially impermeable to the ingredient, the container being movable between an operative position in which it can be sealed to the base and an inoperative position in which it is spaced from the base; 2. drive means to move the filter medium when the container is in its inoperative position so as to bring a new length offilter medium underthe container for each cycle of the apparatus.

3. a piston and cylinderassembly underthe contain- er arranged so that the open top of the cylinder communicates with the base and the piston is operable when the container is in its operative position: a) to pass air upwardlythrough the base into the container and b) subsequently to reduce the pressure beneath the base to assist an infusion in the container to pass through said base into the cylinder; 4. an outlet in the cylinderthrough which the infusion entering the cylinder via the base can be delivered; and 5. operating means to cycle the apparatus by reciprocating the piston, moving the container between its operative and inoperative positions, and for actuating the drive means.

The base may inilude a rigid mesh. When the container is in its operative position the base can be cleared of spent ingredient. This is effected by advancing the filter medium intermittently to remove the length of medium carrying the spent ingredient and to bring afresh length of medium into position underthe containerforthe nextoperation ofthe apparatus.

In the operation of apparatus of this type, as shown for example in U.S.A., Patent No. 3,565,641, at the start of a cycle, the ingredient, e.g. coffee, and the liquid, e.g. hot water, are delivered into the container from above when the piston is in a position between its dead-centre positions and in which the outlet is isolated from the base by the piston. Infusion commences and the piston is then moved upwardly to pass airfrom the cylinderthrough the base and through the mixtureto agitate itto assist infusion. The piston then moves downwardly to reduce the pressure in the cylinder and to draw the infusion through the base into the cylinder, leaving the coffee grounds on the base. When the piston approaches its bottom dead centre position itopenstheoutletsothatthe infusion can be delivered from the cylinder.The container then moves to its inoperative position, the drive means positions a fresh length of filter medium underthe container which then returns to its operative position and the apparatus is readyforthe next cycle.

According to the invention we provide apparatus of the type specified iniluding manually operable disabling meansoperativeto preventthedrive means from gripping the filter medium when the container is in its inoperative position.

The provision ofsuch a disabling means facilitates the feeding into the apparatus of a fresh strip of filter medium since both the container is in its inoperative position and the drive means does not grip the filter medium.

The drive means may comprise a drive roller and associated pinch rollers which cooperate with the drive rollerto feed the filter medium and the disabling means may be operative to hold the pinch rollers out of operative relation with the drive roller.

The container may be carried by a holder pivotable to move the carrier between its operative and inoperative positions and there may be a fulcrummed connection between the holder and the pinch rollers to ensure that the pinch rollers are in their operative position when the holder is in its inoperative position and vice versa. The disabling means may move the effective position of the fulcrum ofthe connection so thatthe pinch rollers are in an inoperative position when the container is in an inoperative position.

The invention will now be described in detail byway of example with reference to the accompanying drawing which an is exploded perspective view of an embodiment of the invention.

Referring to the drawing, the apparatus comprises a support 10 having arms 11 and 1 2and a backplate 13.

The backplate carries a bearing assembly 14 in which is rotatable a driving shaft 15 carrying at one end a crank 16 and at the other end a notched coupling plate 17 whereby it can be rotated bythe shaft 18 of an electric motor, not shown. The shaft 18 carries a coupling 19 having projections to engage the notches ofthe plate 17.

A piston and cylinder assembly is indicated generally at 20 and comprises a cylinder 21 within which is reciprocal a piston 22 by means of a connecting rod 23.

At its lower end the connecting rod has an aperture 24 to fit onto a crank pin 25 on the crank 16. The crank pin 25 has a peripheral groove 26 and the connecting rod is retained in position on the crank pin by means of a detachable connection 27. This comprises a plate 28 having a partial key hole slot 29 in the lower edge thereof. The larger part of the slot 29 is arranged to fit the crank pin 25 and the smaller part ofthe slot is arranged to fit the groove 26. The plate 28 is slidable within a loop 30 on the connecting rod and after initial assembly is retained in the loop.

At its upper end the cylinder 21 is provided with a rectangular flange 31. Theflange is provided with a central aperture 32 which communicates with the open top of the cylinder 21. Surrounding the aperture 32 is a seal 33 received in a recess in the upper surface oftheflange. The seal embraces the edge of a fine mesh 34which thus covers the aperture 32.

Opposite sides ofthe flange 31 are provided with grooves and an d 36 andthese grooves are arranged to engatewith flanges 37 and 38 respectivelyatthetops ofthe arms 11 and 12.Theflanges37 and 38 are provided by angle members 39 and 40 which are secured to the upper ends ofthe arms.

The upper and lower su rfaces of the flanges 37 and 38 and thewalls ofthe grooves 35 and 36 provide mutually interengageable surfaces and the piston and cylinder assembly can be mounted on and demounted from the support by engaging and disengaging the flanges37 and 38 in the grooves 35 and 36. A resilient catch is provided for holding the piston and cylinder assembly in its mounted position and this comprises a projection41 on thy flange 31 having a ridge 42 on its lower surface which can engage with a detent 43 at the top of the back plate 13. The cylinder is provided with an outlet spout 44 secured to the cylinder in alignment with an outletaperture in the wall thereof.

With the connection 27 disengaged, as shown, the piston and cylinder assembly can be mounted on and demounted from the support merely by sliding the piston and cylinder assembly into and out of position by engaging the flanges 37 and 38 in the grooves 35 and 36. When the piston and cylinder assembly is mounted in position the aperture 24 in the connecting rod will be engaged on the crank pin 25.To mountthe connecting rod on the crank pin the detachable connection 27 will have been located so that the larger part of the slot is in alignment with the pin 25.When the piston and cylinderassembly is in position,the connection 27 will be moved downwardly so thatthe smaller part ofthe slot 29 engages in the peripheral groove 26 in the crank pin thus holding the connecting rod in position.

The upward extentofmovementoftheconnection 27 is limited by engagement of a ledge 45 with an edge 46 on a web ofthe connecting rod. A pip 28 a is formed on the outerface ofthe plate 28 and can be moved past the loop 30. When the pip 28 a is above the loop it releasablyholdstheconnection in a position to engage the pin 25 and when the pip is belowthe loop 30 it holds the connection with the smaller part ofthe slot 29 in the groove 26. Rotation ofthe shaft 15 will reciprocate the piston 22 in the cylinder 21.

A generally cylindrical container 50 is provided in which the infusion is made as will hereinafter be described. The container has a bevelled lower edge 51 the lower edge surface being arranged to engage with the seal 33. The container is mounted detachably in an H frame indicated generally at 52. The H frame comprises two side limbs 53 and 54 and is pivotted at one end ofthe limbs 53 and 54to the support by means of a pivot pin 55 received in apertures in the limbs 53 and 54 and in lugs 56 ofthe support. Aspring 57 is arranged to urge the frame 52 upwardly to the position shown as will be described below.

The H frame has a cross member 58 through which passes a connecting rod 59 having a head 60. A spring 61 is engaged between the head and the cross member58. The lower end ofthe connecting rod 59 is secured to a yoke 62 which can be moved downwardly againstthe action of spring 57 buy a cam 63 engaging a roller 64 on the yoke. The cam is mounted on the shaft 15 so 5 so'criL. rotation ofthe shaft 15 reciprocates the connecting rod 59 and moves the H frame 52 downwardlyto move the container 50 to an operative position as will hereinafter be described. The container50 is mounted onthe Hframe 52 bytwo lugs, oneof which is shown at 65. These lugs fit within the channel section side limbs 53 and 54.Attached to each side limb is a spring 66 carrying projections 67 which pass through apertures, not shown, in the upper flanges of the side members.

The container is mounted by pushing the lugs 65 into the side members with the springs 66 raised and then allowing the springs to return to the positions shown so that one of the projections 67 enters an aperture 68 in each lug 65.

The filter medium used in the apparatus is paper in strip form and is indicated at 70. It is pulled across the flange 31 by a drive roller71 which is mounted for rotation between lugs 72 mounted on the angle member40. The drive roller is driven by a pulley 73 driven by a belt74from a pulley 75 on the shaft 15. A doctor blade 76 is provided round the roller71 to preventthewetfilter medium sticking thereto as will hereinafter be described. The surface ofthe drive roller71 is ridged as shown at 77.

Co-operating with the drive rollers a pairofpinch rollers 78 which are mounted on an axle 79 which is in one piece with the pivot pin 55.

An Lshaped connection 80 has one of its limbs 81 received in apertures in the cross member 58 ofthe H frame 52. The otherlimb82 is received in a block 83 which is pivotted on a pin 84to another block 85which embraces the axle 79. The limb 80 engages a fulcrum 86formed on a bracket on the support.

The arrangement is such that when the H frame is in the down position, and therefore the container50 is in its operative position,the pinch rollers are in an inoperative position and do not grip the filter medium againstthe drive roller 71.

When, however, as shown the H frame is in its raised position, and therefore the container in its inoperative position, the pinch rollers are in their operative position and grip the filter medium against the drive roller 71 which is being rotated via the belt 74 and which therefore pulls a fre h strip offilter medium into position as will hereinafter be described.

The spring 57 acts on the axle 79to urge it downwardly and this, through the connection 80, to urge the H frame 52 upwardlyto it inoperative position.

Alatch 87 is provided to movethe pinch rollers 78 to their inoperative position when the H frame is in its upper position and therefore the container 50 is in its inoperative position.This is a desirable requirement to allow the feeding of a new length of filter paper into the apparatus.

Normally,whenthe container is in its operative position the pinch rollers are in their inoperative position and therefore it is not possible to feed a fresh strip of paper because the containerwill be in engagementwith the seal 33. When the container is in its inoperative position, however, the pinch rollers 78 will normally be gripping the filter paper against the drive roll 71. By being able manuallyto liftthe pinch rollers, therefore, when the container is in its inopera tive position, feeding in a new strip of filter medium is facilitated.

The latch 87 is pivotted to the support at 88 and it has a notch, notshown,to engagethe limb 82 ofthe connection 80. This engagement changes the fulcrum point ofthe connection from the position 86 to a position adjacenttothe blocks 83 and 84 andtherefore has the effect of lifting the axle 79 and moving the pinch rollers to their inoperative positions. This enables a fresh length of filter medium to be incorporated in the apparatus while both the container 50 and the pinch rollers 78 are in their inoperative positions.

Operation ofthe apparatus is as follows: the apparatus is set up so that the piston and cylinder assembly is in its mounted position between the arms 39 and 40, the filter medium extends across the top of theflange 31 and around the drive roller71 and the container 50 is received in the H frame 52. At the beginning of a cycle, the containerwill be in its operative ppsition, iethe loweredgethereofwill engage the seal 33 via the strip offilter medium. The pinch rollers 78 will be in their inoperative position and the filter paper will be in engagement with the roller 71. Hot liquid and an infusible ingredient such as coffee are then fed into the container 50 and the shaft 15 rotates.The piston 22 moves upwardly in the cylinderto bubble airthrough the infusion in the container and then moves downwardly to reducethe pressure underthefilter medium and to induce flow of the infusion into the cylinder 21. As the piston approaches its bottom dead centre position it allows the infusion to leave the cylinderthrough the outlet spout 44. As rotation ofthe shaft 15 continues the cam 63will allowthe H frame 52to movetoitsupperor inoperative position and as a result the connection 80 will allow the pinch rollers to be moved downwardly bythespring 57to gripthefiltermedium on the drive roller 71.The drive roller 71 will be rotated to draw a fresh length of filter medium underthe container 50 which is in its inoperative position and the filter paper with the spent coffee or ingredient on it will be moved to the right of the drawing and wetfilter medium will be prevented from sticking to the drive roller 71 by the doctor blade 76. The cycle will be completed by the container 50 being moved back to its operative position readyforthe next cycle and the pinch rollers 78 being moved to their inoperative position.

As has previously been described, when it is required tofit a new length of a filter medium the apparatus is adjusted so that the container 50 is in its inoperative position; the latch 87 is then moved so as to engage the connection 80 to change the fulcrum point thereof and thus to liftthe pinch rollers 78. It is now therefore easy to introduce a new length of filter medium underthe container 50 and underthe pinch rollers 78 and over the drive roll 71 readyforthe next cycle. The latch isthendisengagedsothatthe pinch rollers are free and engage the drive roller. The apparatus will then be adjusted in readiness for the next cycle by rotating the shaftto bring the container 50to its operative position and the pinch rollers78to their inoperative positions.

The latch 87 could be arranged merely to lift the connection 80 ratherthan change the fulcrum point so asto liftthe pinch rollers 78.

Itwill be seen that the invention provides apparatus of the type specified in which, in the embodiment described, the piston and cylinder assembly can easily be mounted on and dismounted from the apparatus for cleaning or replacement, there is a simple mechanical arrangementforthe pinch rollers and H frame which share a single member as their axle and pivot pin respectively and there is means by which the pinch rollers can be lifted with a container in an inoperative position to enable the feeding of a new strip of filter medium into the apparatus.

Claims (4)

1. Apparatus ofthetype specified including manually operable disabling means operative to prevent the drive means from gripping the filter medium when the container is in its inoperative position.

2. Apparatus as claimed in Claim 1, wherein the drive means comprises a drive roller and associated pinch rollers which cooperate with the drive roller to feed the filter medium and wherein the disabling means is operative to hold the pinch rollers out of operative relation with the drive roller.

3. Apparatus as claimed in Claim 1 or Claim 2, wherein the container is carried by a holder pivotable to move the carrier between its operative and inoperative positions and wherein there isfulcrummed connections between the holder and pinch rollers to ensure that the pinch rollers are in their operative position when the holder is in its inoperative position and vice versa and wherein the disabling means moves the effective position of the fulcrum of the connection so that the pinch rollers are in an inoperative position when the container is in an operative position.

4. Apparatus of the type specified substantially as described with reference to the drawings.