Food processor

The invention refers to a mechanical food treatment processor comprising a driving block topped by a bowl unit. The driving block comprises a motor connected to a rotation driving device configured to move a food treatment tool. The bowl unit comprises a functional element electrically supplied via an electric circuit connecting the bowl unit and the driving block. The electric circuit comprises at least two contacts between the bowl unit and the driving block. At least one of the contacts is achieved by the contact of two electrical contact surfaces, respectively located on an external surface of the bowl unit and on an external surface of the driving block. Each of the two electrical contact surfaces is substantially leveled with the external surface of the bowl unit or of the driving block. Such a configuration facilitates the cleaning of the external surfaces of the processor.

RELATED APPLICATIONS

This application claims priority from French Patent Application No. 11 58696 filed Sep. 28, 2011, which is incorporated herein by reference in its entirety.

TECHNICAL FILED OF THE INVENTION

The present invention refers to a mechanical food processor. More precisely, the present invention refers to a food processor such as a blender or a “cutter”.

BACKGROUND OF THE INVENTION

Such a processor is known from the prior art. It typically comprises a driving block topped by a bowl unit. The driving block comprises a driving shaft able to rotate about a vertical or nearly vertical axis. A cutting tool, generally comprising cutting blades, is placed on the driving shaft. The cutting blades can thus ensure the cutting or the mixing of the food placed in the bowl unit, such as fruits or vegetables.

Such a food processor is described for example in document FR2641458.

In addition, it is known to provide the bowl unit with an electric device such as a heater, so as to combine a thermal action with a mechanical action on food.

The bowl unit is in general removable with respect to the driving block. Thus, after the operations of cutting or mixing, said bowl can be raised in order to transfer its contents into another container.

In addition, the electric device supported by the bowl unit is in general power supplied via the driving block. It is thus necessary to provide removable electric connections between the driving block and the bowl unit, as described for example in documents WO2009/103903, WO2009/103904, WO2007/017461 and WO03/001952.

Such electric connections, such as pins and connectors, generally comprises projections complicating the surface cleaning of the bowl unit and of the driving block. However, in particular in a professional environment, it is advantageous to be able to clean quickly and effectively the various elements of a food processor.

In addition, the need for avoiding short-circuits makes these electric connections more complex, which must be in some cases waterproof.

OBJECT AND SUMMARY OF THE INVENTION

The present invention enables to solve these problems and to implement a food processor whose bowl unit comprises an electric functional element, while allowing an easy cleaning of the electrical contact surfaces of the bowl unit and the driving block.

More precisely, the invention refers to a mechanical food processor, said processor comprising a driving block topped by a bowl unit, said bowl unit comprising a container able to receive food; the driving block comprises a power supply means; it moreover comprises a motor connected to a rotation driving means, said driving means being able to make a food treatment tool in the container move when the bowl unit is in a so-called working position on the driving block; the bowl unit comprises a functional element electrically supplied by an electric circuit connecting the bowl unit and the driving block to one another, said electric circuit comprising at least two contacts between said bowl unit and said driving block; at least one, preferably each one, of said contacts is achieved by the contact of two electrical contact surfaces, respectively located on an external surface of the bowl unit and on an external surface of the driving block; the processor is characterized in that each of said two electrical contact surfaces is substantially leveled with the external surface of the bowl unit or of the driving block.

In addition to the container able to receive food, the bowl unit according to the invention can comprise one or more following elements: a lid, possibly provided with a food introduction conduit; a food treatment tool, such as a whisk or a knife; one or more secondary containers mounted in the container; a possibly mobile or removable handle; a base or skirt of the container, possibly removable. This list is not restrictive, the bowl unit being able to comprising other elements known in the state of the art.

By “substantially leveled surface”, one understands that there is a difference in level, which is very small or nil, between the electrical contact surfaces and the corresponding external surface of the bowl unit or of the driving block. Thus, if for example an operator passes a sponge on such an external surface, a possible projection of the contact surface will be too small to form a stop, or a possible cavity in said contact surface will not be very deep to accumulate food remains therein.

Preferentially, the electrical contact surface forms a small projection with respect to the external surface of the bowl unit or the driving block, rather than a cavity.

Such electrical contacts on the surface are manually accessible to a user. They thus require to be protected, in particular the electrical contact surfaces supported by the driving block and connected to the power supply.

One possibility is to supply the electric circuit with a very low voltage, in particular a very low safety voltage (VLSV) or a very low protection voltage (VLPV). The thresholds of these voltages vary according to standards and are in general lower than 50 volts in AC current and 120 volts in D.C. current. A very low voltage circuit is in particular able to supply a functional element such as a temperature sensor in the bowl unit.

When a higher supply voltage is needed, another possibility is to provide the processor with a mechanical safety device. Said device can in particular take: an active state so that an electrical contact surface supported by the driving block is connected to a power supply of said driving block; and a deactivated state so that the electrical contact surface is insulated from the power supply.

Preferably, the safety device is configured so as to be able to be in an active state only if the bowl unit is in the working position on the driving block, the passage from the active state to a deactivated state being carried out by a mechanical action of elements of said safety device.

Such a mechanical safety device comprises for example elements such as switches, examples of which will be described below.

For example, an operation of removing the bowl unit from its working position can be envisaged for causing the passage of the safety device into the deactivated state.

The expression “working position of the bowl unit” concerns all the elements of said bowl unit. More precisely, the displacement of only one of these elements can be considered as a removal from the working position.

For example, the passage of the safety device into the deactivated state can be caused by a rotation of the container with respect to the driving block, or by a rotation or an opening of a lid with respect to the container, or by a displacement of a mobile handle with respect to said container.

According to an alternative, the bowl unit is configured so as to be able to be removed from its working position only if the mechanical safety device is in the deactivated state.

According to a preferential embodiment of the invention, the mechanical safety device comprises a switch firmly fixed to the driving block, said switch being swung into the closed position when the bowl unit is moved into the working position on the driving block, by means of a magnet on the bowl unit. Said closed position corresponds to the active state of the safety device.

More preferentially, the switch is insulated from an external surface of the driving block by a tight protection comprising a flexible membrane.

According to a preferential embodiment of the invention, an electric functional element supported by the bowl unit is a food heating device. More preferentially, said functional element is located in a tight compartment in the bowl unit.

It is understood in all the present text that the terms such as “comprises one/two element(s)” are not restrictive and do not exclude, for example, the presence of additional elements.

According to a preferential embodiment of the invention, the bowl unit and the driving block are configured so that an operation of dismounting/mounting said bowl unit from/onto said driving block causes a friction between the electrical contact surfaces respectively supported by said bowl unit and said driving block. This friction enables to remove possible dirt from these contact surfaces when dismounting/mounting said elements, which improves the electrical contact.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1shows a perspective semi-exploded view of a food processor according to an embodiment of the invention. The processor10comprises a driving block11topped by a bowl unit12.

The bowl unit12comprises a container15able to receive food. The container15has a substantially cylindrical shape of revolution and is disposed along a substantially vertical axis14. The container15itself is topped by a lid13.

The bowl unit12moreover comprises a base16, firmly fixed to a lower part of the container15. The base16has a substantially annular shape so as to be able to fit a support17located in the upper part of the driving block11. The support17substantially has the shape of a disc.

FIG. 2represents a partial schematic view of the processor10according to a vertical cutting plane passing through the axis14. The driving block11comprises a motor19connected to a rotation driving means18for a food treatment tool. Said means is a driving shaft18having a substantially cylindrical shape and disposed along the axis14. The shaft18forms a projection in the center of the support17.

When the bowl unit12is mounted on the driving block11, the shaft18is received inside the container15through a conduit20in a bottom21of said container.

A food treatment tool22is located in the container15and fits on the conduit20and the driving shaft18. The tool22is provided for example with at least one blade23. The action of the tool22, rotationally driven by the shaft18, enables in particular to reduce in pieces or in fine particles of the food introduced into the container15.

In addition, the bowl unit12is provided with an electric functional element24. In the example represented inFIG. 2, the element24is a food heating device. The element24is for example fixed under the bottom21of the container15. Preferentially, the element24is received in a tight compartment25in the bowl unit12, under the container15inside the base16. The element24is for example a heating resistance, which enables to heat or to cook the food introduced into the bowl unit12.

According to an alternative embodiment, the processor10can be provided with an induction heating device. For example, the support17can contain an induction coil and the bottom21of the container15can be made out of a ferromagnetic material adapted to release heat to the food under the action of a magnetic field.

The power supply of the motor19and that of the heating element24can be controlled by a user, via an interface26(FIG. 1) located on the driving block.

The element24is electrically supplied via an electric circuit connecting the bowl unit12and the driving block11. This circuit27can be seen inFIG. 3, which represents a partial schematic view of the processor10according to a vertical cutting plane passing through the axis14. The electric circuit27is connected to a power supply means34for the driving block11. The means34enables to connect the processor10to an electrical supply network.

The electric circuit27comprises at least two contacts between the bowl unit12and the driving block11. These contacts are made of two studs28supported by the bowl unit12, each of said studs28corresponding to with a stud29supported by the support17. The studs29can also be seen inFIG. 1.

The studs28of the bowl unit12are located on a lower external surface30of the compartment25containing the heating element24. Each of said studs28is electrically connected to the element24.

Each stud29is located on an upper external surface31of the support17. When the bowl unit12is mounted on the driving block11for making the processor10work, each stud28comes into contact with the corresponding stud29.

Each stud (28,29) forms an electrical contact surface which is substantially leveled with the corresponding external surface (30,31) of the bowl unit or the driving block. Preferably, each stud (28,29) forms a small projection with respect to the corresponding surface (30,31). The projection is selected to be sufficiently small so that it is possible to clean the surfaces (30,31) of the bowl unit and the driving block, for example by rubbing them with a wet sponge, without abutting against the studs (28,29).

When the bowl unit12is dismounted from the driving block11, as inFIG. 1, a user can come into contact with the studs29supported by the support17. In order to avoid an electrocution, the processor10is provided with a mechanical safety device32.

The device32comprises for example a switch33located on the circuit27, between a stud29of the driving block and the power supply34.

Possibly, the circuit27comprises another safety device41, for example an electrostatic separation system such as a relay.

The device41can also be an electromechanical switch, controlled by an electronic control system (not represented) of the processor10. A program of this electronic control system can deactivate the circuit27when the supply of the functional element24is not needed.

According to an alternative embodiment, the system41detects the presence of the lid13on the container15, for example via a magnet. The system41can deactivate the circuit27as long as the lid13is not in the working position.

Preferably, the bowl unit12and the driving block11are assembled by using a bayonet system. In other words, they can be assembled by covering the support17with the base16, then by rotating the bowl unit about the axis14. Preferably, the bowl unit12and the driving block11are configured so that said rotation causes a friction between the studs28and the corresponding studs29. This friction allows to remove a possible dirt or a possible surface oxidation from these studs, which improves the electrical contact.

FIG. 4shows a partial schematic horizontal section of the base16and the support17.FIG. 4represents some elements of the mechanic safety device32.

An annular internal wall36of the base16supports a magnet35. InFIG. 4, the base16and the support17are represented in the working position of the processor10. The magnet35is located opposite a switch33inside the support17. Between the magnet35and the switch33, there is an opening37in a wall of the support17. This opening is closed by a flexible membrane38, made for example out of plastic or rubber. A metal piece39, preferably made out of a ferromagnetic material, is placed inside this membrane. Advantageously, a water tightness is ensured at the junction between the membrane38and the support17, as well as between the membrane38and the metal piece39.

When the magnet35is located opposite the switch33and the membrane38, the magnet exerts an attraction on the metal piece39and a ferromagnetic piece of the switch. This attraction causes the closing of said switch, so that the heating element24can be electrically supplied.

After using the processor10, the bowl unit12can be dismounted from the driving block11. The dismounting operation comprises a first step of rotating the base16with respect to the support17, in the direction of the arrow that can be seen inFIG. 4. Then, the magnet35moves away from the metal piece39and the switch33. Moreover, a pin or a cam40, located on the internal wall36of the base, pushes the metal piece39towards the switch33. The mechanical action of the metal piece39causes the opening of the switch, which disconnects at least one stud29from its power supply.

Advantageously, each stud29is provided with a switch33and elements such as described above to make the switch swing between an open position and a closed position.

According to an alternative embodiment, it is possible to configure the mechanical safety device32so that, when the bowl unit12is in the working position on the driving block11, an opening of the lid13causes the opening of the switch33. Such a device would be similar to a safety system, as described in document FR2890551, which is incorporated herein by reference in its entirety, for the power supply of the rotary motor.

The device32can also have the possibility of closing the switch33only if the bowl unit12is in the working position, this position in particular comprising a closed lid13.

FIG. 5shows a partial schematic section of an embodiment of the invention which can correspond to the processor inFIG. 3.

In this embodiment, in addition to the heating element24, the bowl unit12comprises another electric functional element50. It can be for example a temperature sensor, located under the bottom21of the container15.

Temperature information provided by the sensor50can be transmitted to the user via a temperature control monitor the interface26is provided with.

The sensor50is for example a CTN thermistor whose resistance varies according to temperature.

The sensor50is supplied with electric power by a very low voltage circuit51. This very low voltage is preferentially lower than 50 volts in AC current. The circuit51is connected to power supply means34via a transformer52.

The sensor50is electrically connected to a stud28′ whose shape is similar to that of the studs28of the previously-described circuit27.

As described previously, when the stud28′ comes in contact with a corresponding stud29′, supported by the driving block11, an electrical contact is generated. The stud29′ has a shape similar to that of the previously-described stud29.

The sensor50is also electrically connected to an element53of the bowl unit12, able to ensure an electrical contact with a corresponding element54of the driving block11when the base16is mounted on the base17. The element54itself is connected to the power supply34by the transformer52.

In addition, the elements (53,54) ensure a equipotential protection or a grounding of the bowl unit12. This grounding is particularly necessary when the processor10comprises a functional element24connected to a circuit27supplied with a voltage higher than the very low voltages. Indeed, the bowl unit preferentially comprises metal elements, such as the container15and the base16.

According to an alternative embodiment, the bowl unit12can comprise only one or more temperature sensors and no heater. A grounding is nevertheless a safety process, even when all the electric circuits of the functional elements of the bowl unit are supplied with a very low voltage.

The elements (53,54) form electrical contact surfaces which preferably are substantially leveled with the external surface30of the bowl unit or the external surface31of the driving block, for the same reasons of cleanability as previously exposed.

In the embodiment represented inFIG. 1, the processor10comprises a heater and two temperature sensors. The support17thus supports two studs29belonging to the previously-described circuit27, as well as two studs (29′,29″) belonging each to a very low voltage circuit.