EP3106075B1

EP3106075B1 - Adjustable dispenser of solid detergent for industrial dishwasher

Info

Publication number: EP3106075B1
Application number: EP16174959.3A
Authority: EP
Inventors: Luigi DE ROCCHI
Original assignee: Chemicount Italiana SNC Di De Rocchi Luigi & C
Current assignee: Chemicount Italiana SNC Di De Rocchi Luigi & C
Priority date: 2015-06-18
Filing date: 2016-06-17
Publication date: 2018-01-03
Anticipated expiration: 2036-06-17
Also published as: EP3106075A1

Description

The present invention relates to detergent dispensers for industrial dishwashers, and in particular to an adjustable dispenser of solid detergent.
It is known that industrial dishwashers used in professional fields (restaurants, bars, etc.) are capable of washing dishes within extremely reduced times, thanks to some constructional features that make them different from domestic dishwashers in various respects. In particular, thanks to the presence of two distinct wash and rinse circuits each having its own sprinklers, the wash water is sprayed onto the dishes by a wash pump. During the rinse a portion of this water is replaced by rinse water preheated in a boiler and fed to the rinse circuit by the direct mains network and in case of low pressure with the aid of a pressure increasing pump. In other words, the wash liquid is not replaced at each operating cycle, but only a small fraction thereof is drained at the end of the wash phase and the drained fraction is replaced with rinse water coming from the boiler.
The detergent must be dispensed automatically in adequate quantity in the wash tank during the initial phase of the water loading in order for the dishwasher to provide washing performances that are satisfactory and constant over time, and the dosage will also be carried out in each subsequent wash cycle. The type of dispenser varies depending on the type of detergent used and on the ability to adjust the delivery according to the washing parameters, such as water hardness, wash temperature and the soiling degree of the dishes.
In the case of liquid detergent the typical prior art dispenser consists of a peristaltic pump that is controlled in parallel to the operation of the rinse solenoid valve in such a way that the detergent is dispensed to have a dosage in the tank indicatively of 2-5 grams/liter, according to the washing parameters as described above.
In the case of solid detergent, typically in tablets up to 6 kg, the dispenser must permit the dilution of the detergent in the wash water. The dispensing of the wash solution is obtained through a solenoid valve which is opened to introduce the dilution water in the solid detergent container where the washing solution forms which is then dispensed by gravity into the wash tank. The opening time of the solenoid valve can be pre-set, by means of a pause/operate timer, to achieve the required dosage in grams/liter based on a calculation of the dilution rate. Otherwise, the dispenser can comprise a control unit which through a capacitive or inductive conductivity sensor measures the concentration of the detergent and closes the solenoid valve of the funnel dissolver upon reaching the pre-set dosage.
These known solutions thus require the presence of components rather expensive and bulky (funnels dilutors, solenoid valve, sensor, control unit) as well as potentially subject to faults that may cause the stopping of the dosage in the dishwasher machine or at least an insufficient dose level. To have a much simpler, inexpensive and reliable delivery system, a solid detergent can also be put directly in the washing liquid sump, alone or enclosed in a container provided with holes and/or grids. It is clear, however, that in this way it becomes impossible to adjust the dosage.
In fact, the solid detergent tablet and/or the compacted tablet (of the type of those used in domestic dishwashers) will rapidly release a quantity of product that will be high in the first washing, while the amount released in the subsequent washings will decrease as the tablet is consumed with fluctuating cleaning results. Even the use of a perforated container does not solve the problem, because if the holes are large enough to permit an easy passage of the dilution water and of the washing solution it is as if the container were not present, while if the holes are quite small as to limit the flows they are also easily subject to clogging, which results in a decreased functionality of the dispenser.
A further variant of this simple solution is described in EP 2796081 which shows a waterproof container of solid detergent that is not perforated, but presents only an upper mouth which is closed by a grid plug containing a water permeable element, typically a sponge, the container being placed in the basket of the dishwasher. However, even this solution does not substantially solve the problem of the variable detergent release as the tablet is consumed, since the magnitude of the incoming and outgoing flows from the container is not adjustable.
Moreover this type of dispenser described in EP 2796081 is designed to be inserted in the basket of the dishwasher machine, which may present substantially two types of risk: a) the handling of the basket made by the operator at each wash cycle can cause spilling of the washing solution that has remained in the product container; b) the dispensing of the product also takes place during the rinse cycle and therefore it is likely that trace of alkaline solution can remain on the dishes. These risks involve a serious danger of burns for the operator and the user of the dishes because the concentrated detergent has corrosive nature, as expressly acknowledged in EP 2796081 .
A similar dispenser is described in US 1904157 which shows always a waterproof container of the solid detergent but whose upper opening is closed by a dispenser cap provided with a central funnel for the entry of water and with peripheral holes for the exit of the washing solution, as recited in the preamble of claim 1. Also in this case the dispenser is not provided with any means of adjustment and is intended to be placed in the wash tank, thus presenting the same problems of the dispenser described in EP 2796081 .
The object of the present invention is therefore to provide a dispenser for solid detergent that overcomes the limitations described above of prior art dispensers. This object is achieved by means of a dispenser comprising a waterproof container provided only with an upper mouth which receives a dosing cap formed by a mounting ring, secured to the container and provided with a plurality of peripheral holes, and an adjusting funnel mounted on said ring and shaped to close a variable number of said peripheral holes depending on the relative position of said funnel with respect to the ring. Other advantageous features are disclosed in the dependent claims.
The main advantage of the dispenser according to the present invention is to add an effective adjustability to the characteristics of simplicity, low cost and reliability typical of the simplest of the prior art solutions.
A further advantage of this dispenser comes from the fact that, contrary to what takes place in the dispenser described in EP 2796081 , the adjustment does not imply any risk of burns for the operator, nor requires the use of other components.
Still another advantage of this solution lies in the possibility of placing the dispenser in the dishwasher sump rather than in the dishwasher basket, thus allowing to fully exploit the loading capacity of the machine only for the dishes.
These and other advantages and characteristics of the dispenser according to the present invention will become apparent to those skilled in the art from the following detailed description of an embodiment thereof with reference to the accompanying drawings in which:

Fig.1 is a perspective exploded view of a dispenser according to the invention;
Fig.2 is a perspective view in the assembled condition of the dispenser of Fig.1;
Fig.3 is a side view of the dispenser of Fig.1;
Fig.4 is a vertical sectional view taken along line IV-IV of Fig.3;
Fig.5 is a vertical sectional view in the assembled condition of the dispenser of Fig.4; and
Figs.6-9 are views from below of the dosing cap, with the ring represented in phantom, showing the different adjustment positions.

Referring to the above figures there is seen that a dispenser according to the invention conventionally comprises a waterproof (non-perforated) container 1 that presents only an upper mouth 1a on which is removably secured a dosing cap. In the illustrated embodiment the cap is secured by means of a thread 1b, but it could also be mounted by means of snap teeth which engage a peripheral rib as in the aforementioned EP 2796081 . The novel aspect of this invention resides in the structure of the dosing cap that is composed of a ring 2, for mounting the cap on container 1, and a dosing funnel 3 that is in turn mounted on ring 2, preferably with the interposition of an O-ring 4.
More specifically, the top portion of ring 2 is provided with a plurality of horizontal holes 2a equally spaced along its periphery, four in the illustrated example, and preferably with the same number of series of sequential markers 2b (although only one series may be sufficient) situated on the top face of ring 2. Each of these series comprises a number of sequential markers 2b equal to the number of holes 2a and ends in correspondence of one of holes 2a, so that in the example illustrated there are four sets of markers with indices from "1" to "4" with the "4" index on top of the corresponding hole 2a. Moreover, on the inner side of the bottom portion of ring 2, below holes 2a, there is formed a thread 2c adapted to be coupled to thread 1b for fixing the cap to container 1.
The funnel 3 has an external diameter substantially equal to the external diameter of ring 2, and is shaped with a vertical collar 3a that extends from its lower side and has an external diameter equal to the internal diameter of the top portion of ring 2, i.e. the portion in which holes 2a are formed. At least one notch 3b, two notches in opposite positions in the illustrated example, is formed along the edge of funnel 3 to allow the vision of one of markers 2b (Fig.2).
The funnel 3 is mounted on ring 2 preferably in a rotatable manner and to this purpose is preferably provided with at least a vertical upper fin 3c, to facilitate the rotational push by the operator, and with at least a lower vertical tooth 3d that engages a bottom horizontal surface 2d (Figg.4-6) of the top portion of ring 2 in which holes 2a are formed. Note that for a smooth operation of the dosing cap it is preferable that said rotational coupling is realized by means of a plurality of coupling means equally spaced along the periphery, like the two opposing teeth 3d shown in Figs.6-9, and that the operator acts on a plurality of fins 3c like the two opposing fins shown in Figs. 1-2.
A central hole 3e allows the entry into container 1 of the water collected by funnel 3, whose upper cone has an inclination α with respect to the vertical preferably equal to 64°±12°, while the "stem" 3f of the funnel presents internally a reverse coning with an inclination β with respect to the vertical preferably equal to 15°±3° (Fig.5). In this way, funnel 3 speeds up the entry of the washing water into container 1 of the solid detergent which is sprayed from above with a "shower effect", so as to form in the upper part of container 1 a saturated solution of detergent that is dispensed through holes 2a having a diameter indicatively comprised between 2 and 8 mm, for example 4 mm, which can be set according to the washing parameters, to the size of the machine and to the number of holes 2a.
The dosage of the detergent solution is achieved by means of vertical recesses 3g formed on the outer peripheral surface of collar 3a and extending down to its bottom end, so as to form channels of access to holes 2a (Fig.5). A seat 3h for the possible O-ring 4 is formed in collar 3a above recesses 3g, so as to achieve a sealed coupling between ring 2 and funnel 3 above holes 2a.
More specifically, as best shown in Figs.6-9, recesses 3g are formed in a number of equally spaced groups equal to the number of holes 2a, the uniform spacing of the groups being referred to the circumferential distance between the first recesses of adjacent groups. Each of these groups of recesses 3g comprises in sequence a progressively decreasing number of equally spaced recesses 3g, starting from the number of holes 2a in the first group to a single recess in the last "group".
In other words, in the illustrated example with four holes 2a, on collar 3a there are sequentially formed four groups of recesses 3g respectively comprising four, three, two and one recess 3g with a 90° angle between the first recesses of adjacent groups. Furthermore, the at least one notch 3b is formed at the first recess of one of said groups.
In the light of the description provided above, the simple and effective operation of the dispenser according to the present invention is readily understood.
The adjustment position illustrated in Figure 6 is that corresponding to the maximum dosage since in this position all four holes 2a are in communication with container 1 because a recess 3g is arranged in correspondence of each hole 2a, and this condition is indicated externally to the operator by the two markers 2b, visible through notches 3b, which show index "4".
More specifically, in the example illustrated, the first recess of each of the four groups of recesses 3g respectively comprising four, three, two and one recess 3g is disposed respectively in correspondence of the left, top, right and bottom hole 2a, the sequence of groups thus proceeding in a clockwise direction starting from the 9 o'clock position. Note that the definitions of holes 2a used here (left, top, right and bottom) are uniquely related to Figs.6-9, given that in actual use the holes are on the same horizontal plane and can be oriented in any direction.
To reduce the dosage of the detergent, it is sufficient to rotate the dosing funnel 3 of about 13° counterclockwise (Fig.7) so that the bottom hole 2a is closed by collar 3a, since the only recess 3g of the corresponding "group" is no longer in correspondence of said hole. On the contrary, the other three holes 2a are still connected to container 1 through the second recess 3g of the corresponding group, this condition being indicated externally by the two markers 2b, visible through notches 3b, which show index "3".
By the same token with similar counterclockwise rotations of about 13° it is also possible to close the right (Fig 8) and top (Fig.9) hole 2a, finally leaving open only the left hole 2a, as respectively indicated by the indexes "2" and "1". Note that a further rotation also causes the closing of the left hole 2a, so that it is possible to extract the dispenser from the dishwasher without the operator risking a burn due to undesired spilling of cleaning solution through holes 2a.
In this embodiment the change of relative position of funnel 3 with respect to ring 2 is achieved through a continuous rotation, in particular thanks to teeth 3d that slide along surface 2d, but for greater positioning accuracy there could be provided a rotation in steps or even a series of predetermined positions of funnel 3 on ring 2 (in which case funnel 3 may not even be fixed to ring 2 but only placed thereon).
For the purpose of being able to place the dispenser in the dishwasher sump rather than in the dishwasher basket, without interfering with the rotation of the sprinkler, its overall height (container + dosing cap) is preferably between 70 and 90 mm. However, other height values outside of this range are obviously possible, depending on the specific dimensions of the dishwasher in which the dispenser is designed to operate.
It is clear that the embodiment of the dispenser according to the invention described and illustrated above is just an example susceptible of various modifications. In particular, the exact number, shape and arrangement of holes 2a and corresponding recesses 3g may vary somewhat depending on the specific production requirements, for example the uniform spacing of holes 2a and recesses 3g is preferred but not strictly necessary, and use could be made of holes 2a and recesses 3g with tapered sections and/or not circular/semi-circular shape, non-horizontal holes and so on, as long as the general structure shown above is maintained.
For example, funnel 3 may be of larger diameter than ring 2 and markers 2b may be visible through holes instead of notches, and in that case collar 3a may have an internal diameter equal to the outer diameter of the top portion of ring 2 and have recesses 3g formed along its inner peripheral surface since holes 2a would be closed from the outside.

Claims

Solid detergent dispenser for dishwasher, comprising a waterproof container (1) provided with a top mouth (1a) which removably receives a dosing cap provided with a central funnel (3) and with peripheral holes (2a), wherein said dosing cap is made up of a ring (2), secured to said container (1) and provided with said plurality of peripheral holes (2a), and characterized in that said funnel (3) is adjustably mounted on said ring (2), preferably with the interposition of an O-ring (4), and shaped so as to close a variable number of said peripheral holes (2a) depending on the relative position of said funnel (3) with respect to the ring (2).
Dispenser according to claim 1, characterized in that at least one series of sequential markers (2b) is located on the top side of the ring (2), said at least one series including a number of said sequential markers (2b) equal to the number of peripheral holes (2a), and the funnel (3) being shaped so as to allow the vision of one of the sequential markers (2b).
Dispenser according to claim 2, characterized in that the series of sequential markers (2b) are present in a number equal to the number of peripheral holes (2a) and the funnel (3) is shaped so as to allow the vision of one of the sequential markers (2b) of at least two of said series.
Dispenser according to any of the preceding claims, characterized in that the funnel (3) is shaped with a vertical collar (3a) that extends from its bottom side and is provided with vertical recesses (3g) formed on a peripheral surface of said collar (3a) and extending down to its bottom end.
Dispenser according to the preceding claim, characterized in that the recesses (3g) are formed in a number of groups, preferably evenly spaced, equal to the number of peripheral holes (2a), each of said groups of recesses (3g) comprising in sequence a progressively decreasing number of recesses (3g), preferably evenly spaced, starting from the number of peripheral holes (2a) in the first group down to a single recess (3g) in the last group.
Dispenser according to claim 4 or 5, characterized in that the collar (3a) has an external diameter equal to the internal diameter of the portion of the ring (2) in which the peripheral holes (2a) are formed and the vertical recesses (3g) are formed on the external peripheral surface of the collar (3a).
Dispenser according to any of the preceding claims, characterized in that the funnel (3) has an upper cone with a slope (α) with respect to the vertical equal to 64°±12° and a stem (3f) that internally has an opposite coning with a slope (β) with respect to the vertical equal to 15°±3°.
Dispenser according to any of the preceding claims, characterized in that the peripheral holes (2a) have a diameter comprised between 2 and 8 mm and are present in a number comprised between two and eight, preferably four.
Dispenser according to any of the preceding claims, characterized in that its height is comprised between 70 and 90 mm.
Dispenser according to any of the preceding claims, characterized in that the funnel (3) is secured on the ring (2) through coupling means that allow a continuous rotation of the funnel (3) with respect to the ring (2), said coupling means preferably consisting of a plurality of vertical bottom teeth (3d) evenly spaced along the periphery of the funnel (3) that engage a horizontal surface (2d) of the ring (2).