Advanced method for filling a pressurised boiler

Abstract

The present invention is for the industry for manufacturing machines for producing hot beverages and relates to a method that allows the filling of the boiler to be managed according to whether coffee is being dispensed, preventing disturbances in the supply of hot water from the boiler during the filling or loading thereof. In addition, microloads and / or fluctuations of state around the maximum level are prevented by means of a delay time for additional filling, managed by a control unit.

Description

[0001] ADVANCED PROCEDURE FOR FILLING A PRESSURIZED BOILER

[0002] DESCRIPTION

[0003] Technical sector

[0004] Industrial sector dedicated to the manufacture of machines for making hot beverages.

[0005] Background

[0006] The state of the art includes documents that refer to the filling of a boiler. Document ES2228186A1, from the owner MFM SL, entitled "Espresso Coffee Machine," refers to a coffee machine that has one or more coffee brewing units, one or more steam dispensers, and one or more hot water dispensers. The machine has a water level control in the boiler using two probes: one for the maximum level and one for the minimum level. Document WO9423623A2, from the owner SEATTLE ESPRESSO MACH CO, entitled "Espresso / Cappuccino Apparatus and Method," discloses an espresso and / or cappuccino machine that has a water level control unit in the boiler using two probes: one for the minimum level, one for the maximum level, and a temperature probe. The boiler filling is controlled based on the water level and temperature.Document CN1742660A, entitled "Water-level control device of Italian coffee-making machine and method", from the holder JINUO INDUSTRY CO LTD, describes a water control device for an espresso machine that has three water level probes and is filled based on four predetermined water levels. Document US2016150911A1, from the holder BREVILLE R & D PTY LTD, entitled "Coffee machine with overflow feature", discloses an espresso machine that has a boiler water level control unit using two or three water level probes. The boiler water level is adjusted based on the water level, temperature, and pressure of the boiler.

[0007] The applicant is not aware of any technical control solutions that, using two level probes, perform control based on the water level in the boiler and whether coffee is being dispensed, that would solve the problem described in an advantageous manner as advocated by the invention.

[0008] Provide simple and efficient means of managing boiler filling based on the boiler level and whether coffee is being dispensed. Another objective is to prevent microloads and / or status fluctuations around the maximum level by means of an additional filling delay time managed by its control unit. Safety protection is also sought by setting a maximum filling time that will block the brewing and heating functions.

[0009] Description of the invention

[0010] Coffee extraction is a process in which many advances have been made in controlling the extraction processes and adapting the machines to them. An unresolved technical problem that causes disruptions in the supply of hot water from the boiler is its filling or loading, since the previous technique does not consider whether the machine is dispensing coffee. Machines for making hot beverages such as coffee and / or infusions typically use a single pressurized boiler with a heating element and usually two heat exchangers that generate water for infusions, steam for preparing milk-based beverages, and water for the coffee through the exchangers. To extract the coffee, a pressure of approximately 9 bars is used due to the restriction generated by the coffee grounds, so the typical flow rates range from 2.0 to 4.0 bar.0 ml / s, if during coffee extraction the boiler load or filling is connected, there is a drop in apparent pump pressure since the boiler load usually requires a flow rate higher than the extraction standards mentioned above. In addition, it is common for several groups to be dispensing simultaneously, in addition to preparing an infusion. This circumstance causes the machine to be unable to reach the pressure of 9 bars at maximum flow rate. This pressure drop can be observed on the pump pressure gauge and also visually perceived in the fall of coffee into the cup. This instability translates into an imbalance of the extraction parameters and reverts to the quality that the dispensing seeks.

[0011] To provide a technical solution to address the above, the invention describes an advanced method for filling a pressurized boiler with at least two heat exchangers, similar to those used in machines for making hot beverages such as coffee and / or infusions. Partial loading or filling is defined as the filling between the minimum and maximum levels of the boiler, while critical loading or filling refers to the minimum level.

[0012] The procedure is carried out in boilers that incorporate a pump and its corresponding control solenoid valve (ELV boiler), a water level control system with at least two probes, one for the maximum level and one for the minimum level, managed by a control unit. The procedure is as follows:

[0013] - Partial load or filling, if the level detected is partially full as interpreted by its control unit through the minimum and maximum level probes, and it is not being dispensed, a filling is produced by activating the pump, being able to reach the full state if the maximum level is detected, if during the load a dispensing is activated the launched load will stop immediately allowing said dispensing without disturbances maintaining the partially full state, so that after finishing the dispensing, the control unit will try to resume the load always stopping in case of starting another dispensing or reaching the full state, in which case when the maximum level is detected; the control unit considers an additional filling delay time to avoid being located right at the maximum level and avoid micro loads and / or state fluctuations around the maximum level.If the full state is not reached without any dispensing that would stop the process within a pre-established maximum filling time, for protection, the control unit for partial loading will show a filling error, giving a visual and / or acoustic indication of the type of error, also blocking the dispensing and heating functions.

[0014] - Critical load or filling, when the control unit interprets the minimum level sensor signal as active, it is determined that the boiler is at a critical volume since the heating resistance cannot be left "in the air" for safety reasons. The loading and filling process proceeds regardless of whether or not there are any deliveries during this process, stopping only if the maximum level is reached, including the aforementioned delay for safety reasons.In the same way as in the partial filling process, if when starting a loading process from the critical minimum level this process cannot be completed after a maximum programmed time has elapsed and the maximum level sensor does not return a detection signal, the control unit will stop the partial loading with a filling error giving a visual indication of the type of error also blocking the delivery and heating functions since this may indicate a problem in the circuit such as flow too slow, obstructions in the pipes, possible leaks, the mains tap has been closed or others.

[0015] Description of the drawings

[0016] For a better understanding of what is described in this document, a list of the process diagrams of the proposed invention is attached.

[0017] Figure 1 shows a process diagram showing the filling error due to time exceeded.

[0018] Figure 2 shows a process diagram considering the start of the filling operation from its minimum level.

[0019] Figure 2 shows a diagram of the process considering the start of the filling operation in which the boiler is partially full (between its minimum and maximum levels).

[0020] Description of a preferred embodiment

[0021] A preferred embodiment is cited as an example, the materials used in its manufacture, as well as the application methods and all the accessory details that may be presented, being independent of the object of the invention, as long as they do not affect its essentiality.

[0022] The preferred description object of this report includes the characteristics of the first claim and in order to provide clarity the procedure is described, this unfolds as has been explained in a machine for the preparation of hot drinks that have a heated boiler, as well as a pump, at least one heat exchanger and at least two level probes used to know the maximum and minimum level, whose signals are interpreted by a control unit, as well as the means known and necessary in this type of machines.

[0023] In this way, the advanced procedure for filling a pressurized boiler considers:

[0024] Partial load or filling, filling occurs by keeping the heating element and the pump on, if the level detected is partially full as interpreted by its control unit through the minimum and maximum level probes, and it is not being dispensed, filling occurs by activating the pump, being able to reach the full state if the maximum level is detected, if another delivery is activated during the load, the launched load will stop immediately allowing the delivery without disturbances maintaining the partially full state, so that after finishing the delivery, the control unit will try to resume the load always stopping in case another delivery begins or reaching the full state, in which case when the maximum level is detected, the control unit considers a small additional filling delay time to avoid being located right at the maximum level and avoid micro loads and / or state fluctuations around the maximum level.If the full state is not reached without any dispensing that would stop the process within a pre-set maximum filling time, for protection, the control unit stops the partial load with a filling error, giving a visual indication of the type of error, and also blocking the dispensing and heating functions.

[0025] - Critical load or filling, when the control unit interprets the minimum level sensor signal as active, it is determined that the boiler is at a critical volume since the heating resistance cannot be left "in the air" for safety reasons. The loading and filling process proceeds regardless of whether or not there are any deliveries during this process, stopping only if the maximum level is reached, including the aforementioned delay for safety reasons.In the same way as in the partial filling process, if when starting a loading process from the critical minimum level this process cannot be completed after a maximum programmed time has elapsed and the maximum level sensor does not return a detection signal, the control unit will stop the partial loading with a filling error giving a visual indication of the type of error also blocking the delivery and heating functions since this may indicate a problem in the circuit such as flow too slow, obstructions in the pipes, possible leaks, the mains tap has been closed or others.

Claims

CLAIMS 1. Advanced procedure for filling a pressurized boiler that includes a heating element, a pump and its solenoid valve, heat exchangers, means for establishing minimum and maximum boiler levels, and a control unit characterized by the following stages: - Partial load or filling, if the boiler level detected is partially full and it is not being delivered, a filling is produced by activating the pump, being able to reach the full state if the maximum level is detected, or if during the load another delivery is activated the launched load will stop immediately maintaining the partially full state, after finishing the delivery, the control unit will resume the load always stopping in case another delivery begins or the full state recorded by the maximum level probe is reached, in which case, the control unit establishes an additional filling delay time;In the event that the full state is not reached without any dispensing that would stop the process within a pre-established maximum filling time, for protection, the control unit for partial loading or filling will reflect a filling error, giving a visual and / or acoustic indication of the type of error, also blocking the dispensing and heating functions; - Critical loading or filling: if the control unit interprets the signal from the minimum level sensor as active, it determines that the boiler is at a critical volume and proceeds to load and fill, whether or not there are any deliveries during the loading process, stopping only if the maximum level is reached, including an additional filling delay time for safety reasons; if, when loading from the critical minimum level is carried out, this process cannot be completed after a maximum programmed time has elapsed and the maximum level sensor does not return a detection signal, the control unit will stop loading with a filling error, giving a visual and / or acoustic indication of the type of error, also blocking the delivery and heating functions.

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