Instant tube heater with homogenous temperature control

Abstract

The invention relates to an instant tube heater (1) for heating flowing liquid comprising: a hollow heating tube (2) comprising a tubular flow passage (20) extending along a central axis (I) for heating liquid as it flows through it, an inlet connector (3) sealingly connected to an inlet end (21) of the hollow heating tube, an outlet connector (4) sealingly connected to an outlet end (22) of the hollow heating tube, a temperature sensor (5) connected to the outlet connector (4) for sensing the temperature of liquid leaving the heating tube, wherein an inlet flow deviating member (6) is positioned locally at the inlet end (21) of the heating tube (2) for forcing the flow of liquid entering the tubular passage of the heating tube in at least one direction away from the direction of the central axis (I) of the tubular passage.

Description

technical field [0001] The present invention generally relates to instant tube heaters that provide a uniform temperature distribution that improves heat exchange between the heating device and the liquid to be heated and increases temperature accuracy. The invention also relates to a beverage preparation machine comprising an instant tube heater. Background technique [0002] Instant tube heaters are known in the art of beverage dispensers such as water dispensers or coffee capsule machines. Advantages include rapid, repeated and economical heating of liquids on demand, for example to brew beverages with single-dose beverage ingredients contained in capsules or pods. Heated tubes are economical because they heat essentially only the volume of liquid required for the liquid to pass through the heated tube. Tube heaters have low inertial mass and do not require any significant warm-up time. Thus, hot beverages are prepared more quickly and require less energy than water he...

AI Technical Summary

Problems solved by technology

Since the NTC sensor preferentially measures the temperature from the center of the tube, the thermoregulation is poor due to the measured temperature being systematically too low

Moving the NTC sensor relative to the tube (towards the hotter region of the temperature gradient) does not provide better regulation

[0008] Also, since the sensed temperature is lower than the true liquid average temperature, the tube tends to overheat, creating a layer of vapor between the heated tube and the liquid inside

This small area of ​​insulation significantly reduces the thermal efficiency of the tube heater

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