Patent Description:
The invention relates to a method to adjust the temperature of an element of a motor vehicle to be interfaced with a passenger of the motor vehicle.

The invention also relates to a motor vehicle comprising said element.

Motor vehicles are known, which basically comprise:.

Such motor vehicle is, for example, known from <CIT>.

The term "element to be interfaced" indicates any component of the motor vehicle accommodated inside the passenger compartment and designed to come into contact - and, hence, exchange heat - with the body or with body portions of the passengers of the motor vehicle.

Typical examples of the aforesaid interfaceable elements are the seat, the steering wheel, the central armrest or the safety belts.

The temperature conditioning system comprises, in turn:.

Following the activation of the conditioning system, the interfaceable elements do not immediately reach the requested temperature.

On the contrary, the change in the temperature of the interfaceable elements largely depends on the exchange of heat with the body of the passenger.

For example, in case of particularly high external temperatures, the passenger, who has a lower temperature, absorbs heat from the seat, which remains at a higher temperature for a given amount of time.

This heat exchange inevitably leads to a feeling of heat and, consequently, of discomfort for the passengers of the motor vehicle.

In order to mitigate this uncomfortable feeling, manufacturers suggested to heat the aforesaid interfaceable elements by means of electrical resistances, which can selectively be activated, or to cool them by means of fans.

Nevertheless, the activation of said electrical resistances and fans is not linked in any way to the thermal feelings perceived by the passengers of the motor vehicle.

As a consequence, there is large room for improvement in terms of the thermal comfort perceived by the passenger of the motor vehicle.

Therefore, the automotive industry needs to improve the thermal comfort perceived by the passengers of the motor vehicle in a simple, quick and automatic manner.

Furthermore, the automotive industry needs to reduce the energy consumptions associated with the air conditioning of the motor vehicle, though without jeopardizing the thermal comfort perceived by the passengers of the motor vehicle.

The object of the invention is to provide a motor vehicle, which is capable of fulfilling at least one of the needs discussed above.

The aforesaid object is reached by the invention, as it relates to a method to adjust the temperature of an element of a motor vehicle to be interfaced with a passenger of the motor vehicle according to claim <NUM>.

The invention also relates to a motor vehicle as set forth in claim <NUM>.

The invention will be best understood upon perusal of the following detailed description of a preferred embodiment, which is provided by way of non-limiting example, with reference to the accompanying drawings, wherein:.

With reference to <FIG>, the drawing shows a motor vehicle basically comprising a body <NUM>, a passenger compartment <NUM>, a steering wheel 15c and a plurality of seats 15a, 15b accommodated in the passenger compartment <NUM>.

Hereinafter, expressions such as "at the top", "at the bottom", "at the front", "at the back", "left", "right" and others similar to them are used with reference to a normal travel direction of the motor vehicle <NUM>.

The motor vehicle <NUM> further comprises:.

The motor vehicle <NUM> further comprises a plurality of elements to be interfaced with a passenger of the motor vehicle <NUM>.

The term "to be interfaced" means, for the purposes of this description, that the elements are in contact and, hence, exchange heat with the passenger, when he/she is inside the passenger compartment <NUM>.

The interfaceable elements each have a respective temperature indicated as Tutenza.

Non-limiting examples of the interfaceable elements are the seats 15a, 15b and the steering wheel 15c, to which reference will be made in the description below without losing generality.

Further example of interfaceable elements are the safety belts or the central armrest or the mats or the door panels of the motor vehicle <NUM>.

In particular, the seat 15a is arranged at the front, opposite the steering wheel 15c and the seats 15b are the remaining front and rear seats of the motor vehicle <NUM>.

The control unit <NUM> is programmed to process the temperature Tprev also based on the temperature Tout.

The control unit <NUM> is programmed to process the temperature Tprev
based on the following formula <MAT> wherein:.

In the specific case shown herein, Trif is <NUM> degrees Celsius.

The parameters α, β and γ and their development relative to the temperature Tout are stored in a storing stage <NUM> of the control unit <NUM> (<FIG>).

As shown in <FIG>, for each temperature value Tout, the coefficient α is smaller than the coefficient β and the coefficient β is smaller than the coefficient γ.

With reference to the temperature Tout and to the increase in the temperature Tout, the development of the coefficient β comprises: - a decreasing segment β1 with a concavity facing downwards;.

With reference to the temperature Tout and to the increase in the temperature Tout, the development of the coefficient α comprises:.

The coefficient β is greater than the coefficient α, given the same temperature Tout.

More in detail, the system <NUM> comprises, for each seat 15a, 15b (<FIG>):.

The system <NUM> further comprises an interface <NUM> (only schematically shown in <FIG>), which can manually be selected to control the heating elements <NUM> independently of the control unit <NUM>.

The interface <NUM> is operatively connected to the heating elements <NUM> and is configured so as to set a plurality of - in the specific case shown herein, three - progressively increasing desired temperatures T1, T2, T3 of the seat 15a, 15b.

In particular, when the temperature T1, T2, T3 is selected on the interface <NUM>, the heating elements <NUM> are operated so as to cause the temperature Tutenza of the seat 15a, 15b, 15c to reach the respective desired temperature value T1, T2, T3 of the seat 15a, 15b.

In the specific case shown in <FIG> and <FIG>, the control unit <NUM> is programmed to set the heating elements <NUM> to a plurality of - in the specific case shown herein, three - discrete operating levels L1, L2, L3.

Each level L1, L2, L3 corresponds to a respective progressively increasing objective temperature T1obj, T2obj, T3obj of the seat 15a, 15b.

More precisely, the control unit <NUM> operates the electrical resistances <NUM> of the heating elements <NUM> with a temperature and for an amount of time that are such as to cause the temperature Tutenza of the seat 15a, 15b to be the same as the corresponding objective temperature T1obj, T2obj, T3obj.

The control unit <NUM> is further programmed to receive the current value of the temperature Tutenza of the seat 15a, 15b and to activate/deactivate the electrical resistances <NUM> of the heating elements <NUM> in feedback mode so as to cause the current value of the temperature Tutenza to be the same as the desired temperature T1obj, T2obj, T3obj.

In particular, the objective temperatures T1obj, T2obj, T3obj associated with the levels L1, L2, L3 are equal to the respective temperatures T1, T2, T3 that can be selected by means of the interface <NUM>.

Similarly, the control unit <NUM> is programmed to set the cooling elements <NUM> to a plurality of - in the specific case shown herein, three - discrete operating levels L4, L5, L6.

In other words, the control unit <NUM> is programmed to cause the fans <NUM> of the cooling elements <NUM> to reach respective levels of angular speed ω that are different from one another, so as to remove quantities of heat power from the respective seat 15a, 15b.

In the specific case shown herein, the levels L1, L3 correspond to the maximum and minimum values, respectively, of the objective temperature T1obj, T3obj of the seat 15a, 15b.

The level L2 corresponds to an intermediate value of the objective temperature T2obj of the seat 15a, 15b.

The levels L4, L6 correspond to the maximum and minimum values, respectively, of the angular speed ω of the fans <NUM> and, hence, to respective maximum and minimum values of the heat power absorbed by the cooling elements <NUM> from the respective seat 15a, 15b.

The level L5 corresponds to an intermediate value, between the values associated with the levels L4, L6, of the angular speed ω of the fans <NUM> and, hence, to a respective intermediate value of the heat power absorbed by the cooling elements <NUM> from the respective seat 15a, 15b.

The control unit <NUM> is further programmed to keep the system <NUM> at a level L0, in which the heating elements <NUM> and the cooling elements <NUM> are deactivated and, as a consequence, do not exchange heat power with the relative seat 15a, 15b.

When the system <NUM> is at the level L0, the temperature Tutenza of the seat 15a, 15b corresponds to a condition of comfort of the passenger of the seat 15a, 15b.

To sum up, from a condition of maximum heating to a condition of maximum cooling of the respective seat 15a, 15b, the control unit progressively sets the system <NUM> to the levels L1, L2, L3, L4, L5, L6.

The system <NUM> comprises a plurality of heating elements <NUM>, for example electrical resistances <NUM>, which are housed inside the steering wheel 15c and can be operated by the control unit <NUM> depending on the temperature Tprev in order to generate a heat flow suited to heat the steering wheel 15c.

To sum up, the control unit <NUM> is programmed to set the system <NUM>, depending on the temperature Tprev:.

The storing stage <NUM> stores a map <NUM>.

The objective temperatures T1obj, T2obj, T3obj, T4obj are also stored in the storing stage <NUM>.

The ranges I1, I2, I3, I0, I4, I5, I6 corresponding to respective levels L1, L2, L3, L0, L4, L5, L6 are associated with the ranges I1*, I2*, I3*, I0*, I4*, I5*, I6* corresponding to the same levels L1, L2, L3, L0, L4, L5, L6.

In particular, each range I1, I2, I3, I0, I4, I5 is delimited by respective maximum and minimum values IMIN and IMAX of the temperature Tprev (<FIG>).

Similarly, each range I1*, I2*, I3*, I0*, I4*, I5* is delimited by respective maximum and minimum values I*MIN and I*MAX of the temperature Tprev.

The maximum value IMAX; I*MAX of each range I1, I2, I3, I4, I0, I5; I1*, I2*, I3*, I0*, I4*, I5* corresponds to the minimum value IMIN, I*MIN of the relative range I2, I3, I0, I4, I5, I6; I2*, I3*, I0*, I4*, I5*, I6* associated with immediately higher temperature values Tprev.

The ranges I6, I6* are delimited by the respective minimum values IMIN, I*MIN of the temperature Tprev and are open at the top, namely they reach values of the temperature Tprev that are greater than the respective minimum values IMIN, I*MIN.

In particular, the ranges I1, I2, I3, I4, I0, I5, I6 have the same width, which is the same as the width of the ranges I1*, I2*, I3*, I0*, I4*, I5*, I6*.

In other words, the difference between the maximum value IMAX and the minimum value IMIN is constant for each interval I1, I2, I3, I4, I0, I5 and is the same as the difference between the maximum value I*MAX and the minimum value I*MAX of each range I1*, I2*, I3*, I0*, I4*, I5*.

The maximum value IMAX of each range I1, I2, I3, I4, I0, I5 is greater than the maximum value I*MAX of the corresponding range I1*, I2*, I3*, I0*, I4*, I5*.

The minimum value IMIN of each range I1, I2, I3, I4, I0, I5, I6 is greater than the minimum value I*MIN of the corresponding range I1*, I2*, I3*, I0*, I4*, I5*, I6*.

The difference between the maximum value IMAx of each range I1, I2, I3, I4, I0, I5 and the maximum value I*MAX of the corresponding range I1*, I2*, I3*, I0*, I4*, I5* is constant and is the same as the difference between the minimum value IMIN of each range I1, I2, I3, I4, I0, I5, I6 and the minimum value I* MIN of the corresponding range I1*, I2*, I3*, I0*, I4*, I5*, I6*.

In this way, the ranges I1, I2, I3, I4, I0, I5, I6 are offset by a constant value relative to the corresponding ranges I1*, I2*, I3*, I0*, I4*, I5*, I6*.

In particular, the control unit <NUM> operates the heating elements <NUM> with a temperature and for an amount of time that are such as to cause the temperature Tutenza of the steering wheel 15c to be the same as an objective temperature T4obj.

The control unit <NUM> is further programmed to receive, from the sensor <NUM>, the current value of the temperature Tutenza of the steering wheel 15c and to activate/deactivate the heating elements <NUM> through feedback.

The storing stage <NUM> stores a map <NUM> and the objective temperature T4obj.

The map <NUM> associates, in particular (<FIG>):.

In particular, the temperature Tsoglia* is lower than the temperature Tsoglia.

The motor vehicle <NUM> further comprises (<FIG>):.

The control unit <NUM> is connected to the sensors <NUM>, <NUM> and is programmed to:.

In use, the sensor <NUM> detects the external temperature Tout on the outside of the passenger compartment <NUM> of the motor vehicle <NUM> and the sensor <NUM> detects the current value of the temperature Tcabina inside the passenger compartment <NUM>.

The sensors <NUM>, <NUM> detect the current temperature Tutenza of the seats 15a, 15b and of the steering wheel 15c.

The passengers set the temperature Trichiesta inside the passenger compartment <NUM> through the interface <NUM> of the conditioning system <NUM>.

Consequently, the conditioning system <NUM>, in a known manner, which is not described herein for it is not deemed necessary for the comprehension of the invention, supplies air at a temperature that is higher or lower than the temperature Tcabina, so as to adjust the temperature Tcabina inside the passenger compartment <NUM> based on the temperature Trichiesta.

In case the sensor <NUM> detects the presence of the passenger of the passenger compartment <NUM> on the seat 15a, the control unit <NUM> operates the system <NUM> for adjusting the temperature of the seat 15a and the system <NUM> for adjusting the temperature of the steering wheel 15c.

On the other hand, in case the sensor <NUM> does not detect the presence of any passenger on the seat 15a, the control unit leaves the system <NUM> for adjusting the temperature of the seat 15a and the system <NUM> deactivated.

Similarly, in case the sensor <NUM> detects the presence of the passenger of the passenger compartment <NUM> on one of the seats 15b, the control unit <NUM> operates the system <NUM> for adjusting the temperature of said seat 15b.

On the other hand, in case the sensor <NUM> does not detect the presence of any passenger on one of the seats 15b, the control unit leaves the system <NUM> for adjusting the temperature of said seat 15b deactivated.

More in detail, the control unit <NUM> processes the value of the parameters α, β based on the temperature Tout.

Furthermore, the control unit <NUM> processes the temperature Tprev based on the temperatures Tutenza, Tcabina and Trichiesta according to the following formula: <MAT>.

The control unit <NUM> further detects the increasing or decreasing time development of the temperature Tprev.

In case the temperature Tprev increases over time, the control unit <NUM> associates the temperature Tprev with one of the ranges I1, I2, I3, I0, I4, I5, I6 and assesses whether the temperature Tprev is lower or higher than the temperature Tsoglia.

In case the temperature Tprev increases over time, the control unit <NUM> associates the temperature Tprev with one of the ranges I1*, I2*, I3*, I0*, I4*, I5*, I6* and assesses whether the temperature Tprev is lower or higher than Tsoglia*.

The control unit <NUM> identifies a level L1, L2, L3, L0, L4, L5, L6 associated with the range I1, I2, I3, I0, I4, I5, I6; I1*, I2*, I3*, I0*, I4*, I5*, I6* corresponding to the temperature Tprev.

The control unit <NUM> has the systems <NUM> associated with the seats 15a, 15b operate the heating elements <NUM>, in case the identified level is L1, L2, L3, or the cooling elements <NUM>, in case the identified level is L4, L5, L6.

In case the identified level is L1, L2, L3, the control unit <NUM> operates the resistances <NUM> of the heating elements <NUM> with a temperature and for an amount of time that are necessary to cause the temperature Tutenza of the seat 15a, 15b to be the same as the objective temperature T1obj, T2obj, T3obj. This determines a progressive increase in Tprev.

Following the variation of the temperatures Tout, Tcabina and Tutenza, the following level L2, L3 is progressively identified, until the level L10 is reached. At this point, the control unit <NUM> orders the systems <NUM> to not operate the heating elements <NUM> or the cooling elements <NUM>, since the temperature Tutenza of the seat 15a, 15b corresponds to the condition of comfort of the passenger of the seat 15a, 15b.

Similarly, in case the identified level is L6, L5, L4, the activation of the fans <NUM> of the cooling elements <NUM> with corresponding levels of angular speed ω of the fans <NUM> determines a decrease in the temperature Tutenza of the seat 15a, 15b and, consequently, a progressive decrease in Tprev.

Following the variation of the temperatures Tout, Tcabina and Tutenza, the following level L5, L4 is progressively identified, until the level L10 is reached. At this point, the control unit <NUM> orders the systems <NUM> to not operate the heating elements <NUM> or the cooling elements <NUM>, since the temperature Tutenza of the seat 15a, 15b corresponds to the condition of comfort of the passenger of the seat 15a, 15b.

With reference to the steering wheel 15c, in case the temperature Tprev is lower than the temperature Tsoglia, in case of increasing temperature Tprev, or than the temperature Tsoglia*, in case of decreasing temperature Tprev, the control unit <NUM> sets the system <NUM> to the ON condition, in which the resistances <NUM> of the heating elements <NUM> are activated.

More in particular, the control unit <NUM> operates the resistances <NUM> of the heating elements <NUM> with a temperature and for an amount of time that are necessary to cause the temperature Tutenza of the steering wheel 15c to be the same as the corresponding objective temperature T4obj.

This determines an increase in the temperature Tutenza of the steering wheel 15c and, hence, in the temperature Tprev, until the temperature Tprev exceeds the temperature Tsoglia, in case of increasing temperature Tprev, or the temperature Tsoglia*, in case of decreasing temperature Tprev.

At this point, the control unit <NUM> sets the system <NUM> to the OFF condition, in which the heating elements <NUM> are deactivated, since the temperature Tutenza of the steering wheel 15c corresponds to the relative comfort value.

The disclosure above reveals evident advantages that can be obtained with the invention.

In particular, the control unit <NUM> is programmed to:.

In this way, the temperature Tutenza of the seats 15a, 15b and of the steering wheel 15c is adjusted based on the temperature Tprev and, hence, also based on the temperature Trichiesta requested by the passenger of the passenger compartment <NUM> and on the temperatures Tcabina, Tutenza perceived by the aforesaid passenger.

This significantly increases the passengers' comfort compared to known solution identified in the introduction to the description.

The control unit <NUM> is further programmed to operate the systems <NUM>, <NUM> only when the sensor <NUM>, <NUM> detects the presence of the passenger on the respective seat 15a, 15b.

This reduces the energy consumptions associated with the air conditioning of the motor vehicle <NUM>, nevertheless maximizing the thermal comfort perceived by the passengers of the motor vehicle <NUM>.

The minimum value IMIN of each range I2, I3, I4, I0, I5, I6 is greater than the minimum value I*MIN of the corresponding range I2*, I3*, I0*, I4*, I5*, I6*.

Similarly, the temperature Tsoglia of the range J1 is greater than the temperature Tsoglia of the interval J1*.

In this way, the maps <NUM>, <NUM> feature a constant deviation - indicated in <FIG> as fixed hysteresis - between the ranges I1, I2, I3, I4, I0, I5, I6, J1 concerning decreasing temperatures Tprev and the corresponding ranges I1*, I2*, I3*, I0*, I4*, I5*, I6*, J1* concerning decreasing temperatures Tprev.

Said hysteresis compensate for possible hysteresis errors of the sensors <NUM>, <NUM>, <NUM>, <NUM>.

The objective temperatures T1obj, T2obj, T3obj associated with the levels I1, I2, I3 are identical to respective temperatures T1, T2, T3 of the seat 15a, 15b that can be selected by means of the manual interface <NUM>.

In this way, the control unit <NUM> automatically controls the heating elements <NUM> so as to give the passenger on the seat 15a, 15b a feeling of comfort that is substantially identical to the one that he/she would obtained by manually acting upon the interface <NUM>.

Finally, the method and the motor vehicle <NUM> according to the invention can be subjected to changes and variations, which, though, do not go beyond the scope of protection set forth in the appended claims.

In particular, the system <NUM> for adjusting the temperature of the steering wheel 15a and, more in general, of any element to be interfaced with the passenger of the passenger compartment <NUM>, other than the seat 15a, 15b, could be similar to the system <NUM> and be controlled by the control unit <NUM> similarly to the system <NUM>.

In other words, the system <NUM> could comprise heating elements and cooling elements similar to the heating elements <NUM> and to the cooling elements <NUM>, respectively; and the control unit <NUM> could be programmed to control the heating elements and the cooling elements of the system <NUM> according to a plurality of discrete levels similar to the levels L1, L2, L3, L0, L4, L5, L6; and the storing stage <NUM> could contain a map for controlling the heating elements and the cooling elements of the system <NUM> similar to the map <NUM>.

Claim 1:
A method to adjust a first temperature (Tutenza) of an element (15a, 15b, 15c) of a motor vehicle (<NUM>) to be interfaced with a passenger of the motor vehicle (<NUM>), comprising the steps of:
i) adjusting a second temperature (Tcabina) on the inside of a passenger compartment (<NUM>) of said motor vehicle (<NUM>) based on a third temperature (Trichiesta) currently requested to an adjustment system (<NUM>, <NUM>) for said second temperature (Tcabina) itself;
ii) detecting a fourth external temperature (Tout) on the outside of a passenger compartment (<NUM>) of said motor vehicle (<NUM>); and
iii) detecting a current value of said second temperature (Tcabina) on the inside of said passenger compartment (<NUM>) of said motor vehicle (<NUM>);
iv) detecting a current value of the first temperature (Tutenza) of said element (15a, 15b, 15c);
v) processing a fifth temperature (Tprev) based on said first, second and third temperature (Tutenza; Tcabina; Trichiesta); and
vi) exchanging a heat power with said element (15a, 15b, 15c) so as to adjust said first temperature (Tutenza) based on said fifth temperature (Tprev);
said step v) comprising the step vii) of processing said fifth temperature (Tprev) also based on said fourth temperature (Tout);
characterized in that said step vii) comprises the step viii) of processing said fifth temperature (Tprev) based on the following formula: <MAT>
wherein:
- TRIF is a sixth reference temperature that can selectively be set;
- α and β are coefficients that depend on said fourth temperature (Tout) and are independent of said first, second and third temperature (Tutenza; Tcabina; Trichiesta); and
- γ is a constant coefficient.