Gas cylinder coupling and weighing mechanism for a carbonated drink dispenser

Abstract: A gas cylinder coupling and weighing mechanism useful in a carbonated drink dispenser having a gas cylinder. Supports the cylinder rotatably within a hood (741), the hood forming a lever which is biased upwardly by a spring (765). A full cylinder will pull the hood all the way down. As the cylinder is emptied, the hood will begin to move upward and when the cylinder is empty the hood will be fully upward. Mounted inside the hood is a fitting (740) engaging with a mating fitting on the gas cylinder. The mating fitting is equipped with a pair of arms which are aligned with locking slots contained within the mating fitting which are used to engage pins on the fitting inside the hood when mounting the gas cylinder.

Description: This invention relates to apparatus useful in a carbonated drink dispenser in general, and more particularly to a mechanism for weighing the contents of a gas cylinder for such dispenser. BACKGROUND OF THE INVENTION US Patent 4,520,950 discloses an in-home drink dispenser which includes a source of concentrate, e.g. syrup, a carbonator which is filled with ice and water and a carbon dioxide tank for supplying carbon dioxide to carbonate the water in the tank. In such an in-home drink dispenser, it is, of course, important to know how much carbonated water is left and also how much carbon dioxide is left. Knowing when one is about to run out of carbon dioxide is of great importance, particularly where a cylinder is not immediately on hand. The carbonator can be refilled with water and ice; however, if one runs out of carbon dioxide, at a time when the supplier is not open for business, it may be necessary to wait, possibly over a weekend, to get a new cylinder. Thus, the need for an indication of this level is particularly important. US Patent 2,009,768 discloses a mechanism for weighing the contents of a gas cylinder wherein the gas cylinder is suspended from a fitting and is hung on a pivotal bracket. The bracket is supported by a suspension device which also carries a counter balance and weighing arm. The mounting of the cylinder on the bracket tends to pivot the bracket in one direction on the suspension device, whilst the counter balance weight tends to pivot the bracket in the other direction and there is no pivoting when the two are in balance. As the contents of the gas cylinder are used up, in order to weigh the remaining contents the user must reposition the balance arm until balance is achieved at which position the pointer indicates the remaining contents. This weighing mechanism is not automatic in operation, and requires the constant adjustment of the balance arm by the user. German Patent Specification 206627 on the other hand discloses a suspension device for a gas cylinder which device defines a cradle in which the cylinder sits. The cradle forms a parallelogram support linkage and a spring axe to move the linkage and hence the gas cylinder upwardly. The wait of the gas cylinder tends to urge the linkage downwardly and therefore a balance is achieved. As the cylinder contents are used up, so the linkage is moved upwardly under the spring axe, and a relatively fixed scale pointer moves in relation to a scale to indicate the residual contents of the cylinder. In each of these arrangements there is a progressive adjusting function with the progressive utilisation of the cylinder contents. The present invention seeks tc provide a weighing mechanism with an indicator whereby the user does not continuously have to keep a check upon the weighing mechanism or to continuously operate the mechanism. SUMMARY OF THE INVENTION The present invention provides a mounting and weighing mechanism for a gas cylinder comprising: (a) a first fitting, said first fitting comprising a cylindrical member containing a passage for conducting gas and having on the outside surface thereof means for engaging a second mating fitting of a gas cylinder such that the gas cylinder is suspended from said first fitting; and (b) a weighing mechanism to which said first fitting is attached including: means forming a rotatable lever at the end of which said first fitting is mounted; means for biasing said lever upwardly against the downwardly acting weight of said gas cylinder; and indicator means for indicating the relative positions of said second fitting as the cylinder empties, characterised in that said biassing means is effective to move said cylinder upwardly over a fraction of its weight representing an almost empty condition of the cylinder. In accordance with the preferred arrangement of the present invention, the fitting to which the gas cylinder is attached is supported rotatably within a hood, the hood forming a lever which is biased upwardly. The hood rotates on a shaft supported in a bracket which is attached to a wall of the dispenser. Springs act between the bracket and the hood to bias the hood upwardly. A mechanism, including a planar member, which is guided in a curved slot, maintains the first fitting in a pre-determined position so that in any position the user can easily insert a gas cylinder onto the first fitting without difficulty. The planar member which is guided and which maintains the first fitting in said pre-determined position is also provided with indicators visible through a window to indicate the degree of the fullness of the cylinder. A full cylinder will act against the spring and pull the hood all the way down. As the cylinder is used up, the hood will begin to move upwardly until, when the cylinder is completely empty, the good will be fully up. In accordance with the present invention, the spring is adapted to begin moving the gas cylinder upward only over the last part of the supply, e.g. the last ten percent. Thus, as soon as movement starts the user knows that he is getting near the end of his supply. A cylindrical member which engages the first fitting is formed with a pair of arms. The arms are aligned with axial slots which are used for engaging the pins on the first fitting when locking the two fittings together. By aligning the arms with the axial slots, the user is given a guide and knows exactly how to line up the gas cylinder to insert it onto the first fitting. Preferably, on the hood, there are alignment markings and an arrow, indicating to the user the direction in which to rotate the handles or arms so as to lock the cylindrical member and, therefore, the CO₂ cylinder in place. In the illustrated embodiment, there are holes at the ends of the arms through which a finger can be inserted to hold the gas cylinder. A cover is also placed over this fitting for decorative and protective purposes. The cover has a tear-away tab on the top to allow access to the cylindrical member and fitting when attaching to the probe fitting. The tab cover, however, provides protection during shipping and remains in place until the cylinder is to be used. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view of an in-home drink dispenser in which the mechanism of the present invention may be used. Fig. 2 is a view similar to Fig. 1 showing the door to the carbonator compartment and CO₂ compartment opened. Fig. 3 is an exploded view of the elements attached to the top of the CO₂ cylinder. Fig. 3A, 3B and 3C are views to illustrate operation of the thin probe. Fig. 4 is an elevation view partially in cross section showing the manner in which the CO₂ assembly is attached to a probe fitting in which is incorporated a regulator and also shows part of the weighing mechanism. FIG. 5 is a perspective view showing the cylindrical member which permits attachment to the probe fitting of FIG. 4. FIG. 6 is an exploded view of the weighing mechanism of the present invention. FIGS. 7 and 8 are elevation views, partially in cross section and partially in phantom showing the operation of the weighing mechanism, FIG. 7 showing the weight mechanism with an empty cylinder and FIG. 8 showing the weighing mechanism with a full cylinder. DETAILED DESCRIPTION OF THE INVENTION FIGS. 1 and 2 are perspective views of the in-home drink dispenser in which the mechanism of the present invention may be used. FIG. 1 shows the drink dispenser 11 with its doors closed. FIG. 2 shows the dispenser 11 with its carbonator door 13 and CO₂ compartment door 15 opened, and the CO₂ cartridge 17 and carbonator tank 18 removed. Also visible in FIG. 2 is the syrup cartridge 19. The CO₂ cylinder 17 has a cover 23 for ease in handling and also for mounting into the machine in a manner to be described below. FIGS. 3-5 illustrate the cover assembly for the carbon dioxide cylinder 17 and its connection to a regulator which also acts as a weighing mechanism. Referring to FIG. 3, over the end of the gas cylinder 17 there is placed an O-ring seal 701. Next a member 703, which has an inner washer-like portion, is placed over the neck section 704 of cylinder 17, and held in place by a flange on threaded fitting 705 threaded into the threads 707 in the neck section of the cylinder 17. The fitting 705 contains a check valve which is operated when an appropriate pin or probe is inserted into its opening 709. The pin and valve opening arrangement are shown in Figs. 3A, 3B and 3C, and referring to these figures, the fitting 705 is shown as having the opening 709 which leads to a chamber 709A containing a valve ball 709B which is urged by a spring 709C against a seat at the end of opening 709. The ball 709B therefore prevents the escape of carbon dioxide through the opening 709. The member 713 which operates the valve ball 709B and which is described hereinafter is also shown, and this member is provided with a slender probe 731A which, when the members 731 and 705 are brought together, enters the opening 709 as shown in Fig. 3B and unseats the ball 709B allowing carbon dioxide to flow from the carbon dioxide cylinder. An O-ring seal 709D in the opening 709 engages the wall of the probe 731A to prevent escape of gas passed the said seal 709B when the ball 709B is unseated as shown. As shown in Fig. 3C, the probe 731A is provided with a small bore 731B which is offset relative to the centre line of the probe so that the ball 709B will not in fact block the bore 731B through which the gas has to escape in order to enter the dispenser. The characteristic of the probe 731A is that it is of small diameter compared to conventional probe connections as used for carbon dioxide cylinders. Usually these probe connections require the assistance of a mechanical advantage device to enable the cylinders to be connected to the dispensers, whereas in the case of the present arrangement, the probe is of such small diameter that connection can take place by the application of manual force. Typically, the probe diameter may be of the order of 1/8th inch for use with a gas cylinder of which the internal pressure is of the order of 800 lbs per square inch. With this arrangement, a force of only 10 lbs is required in order to connect the gas cylinder to the fitting 731, but it is within the scope of this invention to use cylinder probes of different diameter depending upon the internal pressure of the gas cylinder, but optimally one should aim for providing an arrangement wherein a coupling force of the order of 10 lbs is all that is required in order to couple the cylinder to the fitting. Member 703 contains a central cylindrical portion 711 with two arms 713 at the ends of which rings 715 are formed as finger grips. As best seen from FIG. 5, on the inside of the cylindrical portion 711 are formed two diametrically opposed axially extending slots 719 which lead to circumferentially extending locking slots 720. These are also shown in FIG. 4. A cover 23 is snapped over the member 703 to give the cylinder the finished appearance illustrated in FIG. 2. The cover is snapped so as to enclose the top of the cylinder 17 as well as the member 703 and includes side parts 721 with openings 723 which align with the openings 715 formed in the arms 713 of member 703. These openings permit a finger grip for ease in handling of the cylinder. The cover 23 contains a tear-away top portion 725 with a tab 727 provided to tear off the cover to permit ease of access to the fitting 709. The handles 713 or 721 also act as an alignment means. As can be seen from FIG. 5, the axial slots 719 are aligned with the handle 721. Thus, when inserting the gas cylinder on to regulator assembly 729 which has a mating fitting 731 with projections 733 thereon, for engaging in the slots 719 and 720, the handles can be used for alignment purposes. The user simply lines up the handles with the pins 733 and then rotates the handles 721 until they are in a predetermined position in which the cylinder is locked in place against the fitting 731. The fitting 731 includes the hollow probe 731A (not shown in Fig. 4) which fits in and seals within the opening 709 and opens the valve therein to permit the flow of carbon dioxide through the regulator and into the rest of the system. The regulator is also shown in FIG. 6 which is an exploded view of the regulator and weighing assembly. The fitting 731 of the regulator 729 with its pins 733 is visible at the bottom of FIG. 6. A shaft 735 extends out from both ends of the regulator. Shaft 735 on the left hand side contains a flat 737. A member 739 to be described in more detail below is placed over this end of the shaft 735. The whole assembly, generally indicated as 740 is inserted into a hood 741 containing holes 743 on each side thereof for accepting the shaft 735. The shaft 735 on the left hand side is held in place In a cylindrical recess 745 attached to the regulator 729 by means of a cotter or split pin 747. Thus, after the shaft 735 on the right hand side is inserted through its hole 743, the recess 745 is aligned with the hole 743 on the left and the shaft 735 on the left hand side inserted and secured in place with cotter or split pin 747. Thereafter the member 739 can be placed over the end of the shaft 735. The hood 741 has a brim 749 containing thereon indicia 751 and 753 along with arrows 755. The indicia indicate to the user the proper alignment for the handles 721 in the position where the bottle is inserted and the positiion where it is locked in place. The hood 741 is held in an assembly 757. This assembly Includes a U-shaped bracket 759 having holes 761 in its base for mounting within the gas cylinder compartment of the dispenser. Extending through the two legs of this U-shaped bracket 759 is a shaft 763. At each end of the shaft is a spring 765. This is a coil spring containing arms 767 and 769 each of which are bent at their ends so as to have a portion parallel to the axis of the spring. The portion 767 contains an axially extending portion 771 and portion 769 contains an axially extending portion 773. Portion 771 engages in one of a plurality of holes 775 in the arm of the bracket 759. The bracket 759 encloses the rear portion of the hood 741 with the shaft 763 extending through the opening 777 and the inwardly extending portion 773 engaging in holes 779. Thus, hood 741 rotates on shaft 763 and is biased upwardly by springs 765. FIGS. 7 and 8 illustrate the manner in which the weighing mechanism operates. The previously mentioned member 739 comprises a planar member containing an arcuate slot 781 therein. The slot 781 slidably engages a pin 782 provided on the inside of one of the walls of the cylinder compartment which is adjacent to the planar member 739. Its purpose is to maintain the axis of the fitting 731 vertical irrespective of the rotation of the hood 741. FIG. 7 shows the hood 741 rotated upwardly, corresponding to an empty bottle or no bottle in place. FIG. 8 illustrates the hood 741 rotated downwardly with a full bottle In place. It will be recognized, that the locus of shaft 735 moving between the positions of FIGS. 8 and 9 will exhibit curved motion and, were It not for the slot 781 and pin 782 and the rigid connection of the member 739 to the shaft 735, which in turn is rigidly connected to the regulator 729 and thus to the fitting 731, rotation of the regulator 729 and fitting 731 would take place. It is important that the axis of the fitting 731 be maintained vertical so that CO₂ bottles can be easily removed and inserted. The springs 765, thus, tend to bias the cover 741 upwardly into the position shown in FIG. 7. The weight of a full CO₂ cylinder acts against this biasing action to bring the cover downward to the position shown in FIG. 8. The biasing force of the spring 765 may be changed based on the users selection of the various holes 775 is bracket 759. The member 739 performs a second function, the function of an indicator. At the bottom of the member 739 are painted two areas 783 and 785. Area 783 is painted green, for example, and area 785 is painted red. A viewing window 787 is provided in the drink dispenser housing through which the painted areas 783 and 785 can be observed. With a full bottle, one looks through the viewing window 787 and sees the green area 783. As the bottle begins to empty, the red area 785 begins to appear until, when all red, the bottle is essentially empty. Preferably, the biasing force of the springs 765 is such that they operate only over the last ten percent of carbon dioxide in the bottle. That is to say, only when the bottle is, for example, 10 percent full will the bottle become light enough so that the spring begins to move the cover 741 upwardly. This gives a better indication at the end of supply than would a linear system which would be difficult to calibrate.

Claims: A mounting and weighing mechanism for a gas cylinder (7) comprising: (a) a first fitting (731), said first (731) fitting comprising a cylindrical member (731) containing a passage for conducting gas and having on the outside surface thereof means (733) for engaging a second mating fitting (703) of a gas cylinder (17) such that the gas cylinder (17) is suspended from said first fitting (731); and (b) a weighing mechanism (740,741,757) to which said first fitting is attached including: means forming a rotatable lever (741) at the end of which said first fitting (731) is mounted; means (773) for biasing said lever (741) upwardly against the downwardly acting weight of said gas cylinder (17); and indicator means (783,785,787) for indicating the relative positions of said second fitting (731) as the cylinder (17) empties, characterised in that said biassing means (773) is effective to move said cylinder (17) upwardly over a fraction of its weight representing an almost empty condition of the cylinder (17). A mechanism according to claim 1, characterised in that said indicator means (783,785,787) includes a planar member (739) which hangs from said lever (741) and by means (729) for mounting said first fitting (731) to said lever (741) in such a way that said planar member (739) is maintained vertical as said lever (741) rotates. A mechanism according to Claim 2 characterised in that said lever (741) comprises: a hood (741) having a top and side walls, a rounded front wall and a brim (749) extending therefrom, holes (743) formed in said side walls near said front wall; a shaft (735) extending from each side of said first fitting (731) passing through said holes (743) in said side walls whereby said first fitting (731) is rotatable with respect to said hood (741); and means (737) for maintaining said first fitting (731) such that said planar member (739) is vertical by bringing about relative rotation between said first fitting (731) and said hood (741) as said hood (741) rotates. A mechanism according to Claim 3, characterised in that said means biasing comprises: a U-shaped bracket (757) having a base (759) and two extending arms, said base (759) mounted to a vertical wall, a hole formed in each arm; a shaft (763) passing through said holes, said side walls of said hood having holes (777) at the rear thereof through which said shaft (763) passes, said hood (741) thereby being rotatable on said shaft (763); and at least one spring acting (773) between said arm of said bracket and said hood (741) biasing said hood (741) upwardly. A mechanism according to Claim 4, characterised in that the biasing force of said spring (773) is such as to be effective to move said gas cylinder (17) upwardly only over a fraction of its weight. A mechanism according to Claim 5, characterised in that said fraction is about one-tenth. A mechanism according to Claim 6, characterised in that said means maintaining said planar member (739) vertical comprises: means coupling said member (739) at one end to one end of said shaft (735) extending from said first fitting (731), said planar member having a curver slot (781) therein; a wall formed parallel to said planar member; and a pin (782) extending from said wall and slidably engaging said planar member curver slot (781), guiding said planar member (739) so that it remains vertical as said hood (741) rotates, whereby said planar member (739) will also remain vertical. A mechanism according to Claim 7, characterised in that said indication means includes a viewing hole (787) and said planar member (739) contains colour coded areas (783,785) viewable through said viewing hole (787) such that the position of said planar member (739) and thus the weight of said gas cylinder (17) will be indicated. A mechanism according to Claim 1, characterised by a regulator (729) formed integrally with said first fitting.

Inventors: ANDERSEN GEORGE J, DOLE CHARLES MINOT, JEANS EDWARD LEWIS, KARLISS ROBERT GALE, WEBSTER GARY LAWRENCE, ANDERSEN, GEORGE J., DOLE, CHARLES MINOT, JEANS, EDWARD LEWIS, KARLISS, ROBERT GALE, WEBSTER, GARY LAWRENCE
Applicants: CADBURY SCHWEPPES PLC
Application year: 1986
Main classification: B67D1
IPC codes: B67D1