Patent Publication Number: US-2005118944-A1

Title: Heating, ventilating and/or air conditioning apparatus for a motor vehicle cabin, with temperature regulation by zone

Description:
This invention relates to the field of heating, ventilating and/or air conditioning for motor vehicle cabins.  
      More particularly, it relates to apparatus for heating and ventilating and/or air conditioning for a motor vehicle cabin, which comprises a casing that includes an upstream chamber, which feeds fresh air to an auxiliary duct for supplying at least one first duct for feeding a rear zone of the cabin under the control of first air distribution means, a first mixing chamber for feeding processed air to second ducts for supplying a front zone of the cabin, and a heating chamber for supplying heated air to the mixing chamber and the first duct or ducts.  
      It is already known, especially from FR 2 795 683 and FR 2 795 684, to provide apparatuses of this type. They enable the atmospheric parameters in a motor vehicle cabin to be regulated in a front zone and a rear zone of the latter.  
      These known apparatuses work satisfactorily, but they do have the disadvantage that the air distribution means which control the rear zone of the cabin make it necessary to provide a number of valves with complex kinematics, which increases the complexity of the apparatus.  
      In addition, the said distribution means are bulky and in consequence they increase the size of the apparatus, so that the space available for items of motor vehicle equipment is more and more limited.  
      A main object of the invention is to overcome the above mentioned drawbacks.  
      In consequence, it proposes an apparatus of the type defined in the introduction hereof, which includes at least one second mixing chamber situated at the intersection of the auxiliary duct with the heating chamber and first duct, and a single distribution shutter valve having a first control member for selectively distributing a part of the heated air from the heating chamber either towards the first mixing chamber or towards the second mixing chamber, whereby to produce therein a stream of mixed air, together with a second control member adapted to control the distribution of the mixed air from the second mixing chamber through the first duct or ducts.  
      The apparatus of the invention thus includes a single distribution shutter valve, the function of which is essentially, firstly to distribute selectively a part of the heated air coming from the mixing chamber, and secondly to control the distribution of the mixed air taken from the second mixing chamber through the first duct or ducts, that is to say towards the rear zone of the cabin.  
      This results in simplification of the apparatus and reduction in the overall size of the latter.  
      In one preferred embodiment of the invention, the single distribution shutter valve includes an axis of rotation which carries the first control member and the second control member, and the first control member is arranged to cooperate with a first wall which is situated in the heating chamber and which delimits an air passage for the said part of the heated air, while the second control member is arranged to cooperate with a second wall which contributes to the delimitation of the second mixing chamber, and into which at least one air outlet, for feeding the first duct or ducts, exhausts.  
      In a first modified embodiment of the invention, which is of simplified design, the second wall includes a single air outlet which feeds a single first duct, the distribution shutter valve is displaceable between a first position, in which the first control member opens the air passage while the second control member closes off the air outlet, and a second position, for rear air distribution, in which the first control member closes off the air passage while the second control member opens the air outlet.  
      Complementary and/or alternative features of this first modified embodiment are as follows: 
          the first control member includes a generally rectangular vane, which extends from the axis of rotation and which is bounded by an edge adapted to cooperate with the first wall, while the second control member includes a shell element fixed to the axis of rotation and arranged for cooperation with the second wall, which is of cylindrical form;     the first wall ends in a terminal edge with which the edge of the first control member co-operates when the distribution shutter valve is in the rear distribution position.        

      In a second modified embodiment of the invention, which has a more developed design, the second wall includes at least two air outlets which are offset circumferentially with respect to the axis of rotation and which supply two first ducts, and the distribution shutter valve is displaceable between a first distribution position in which the first control member opens the air passage while a second control member closes off the two air outlets, and two rear distribution positions in which the first control member closes off the air passage while the second control member opens a respective one of the two air outlets.  
      Complementary and/or alternative features of this second variant are as follows: 
          the two air outlets comprise a rear foot zone outlet and a rear ventilating outlet, which feed, respectively, a rear foot zone duct and a rear ventilating duct, and the distribution shutter valve is displaceable between a first extreme position, which corresponds to the first distribution position, and a second extreme position which corresponds to a rear ventilating position in which the rear ventilating outlet is open, the distribution valve occupying at least one intermediate position which corresponds to a rear foot zone position in which the rear foot zone outlet is open;     the first control member includes a generally rectangular vane, which extends from the axis of rotation and which is bounded by an edge adapted to cooperate with the first wall, while the second control member includes a shell element fixed to the axis of rotation and arranged for cooperation with the second wall, which is of cylindrical form, together with a radial vane which is arranged to close off the rear foot zone outlet when the distribution valve is in its rear ventilating position; and     the first wall comprises a circular cylindrical portion with which the edge of the first control member co-operates when the distribution valve is in one or other of its rear distribution positions.        

      In a third modified embodiment, which corresponds to another developed design, the second wall includes at least two air outlets which are offset axially on a common generatrix which is parallel to the axis of rotation, and which feed two first ducts, and the distribution shutter valve is displaceable between a first position in which the first control member opens the air passage while a second control member closes off the two air outlets, and two rear distribution positions in which the first control member closes off the air passage while the second control member opens a respective one of the two air outlets.  
      Complementary and/or alternative features of this third variant are as follows: 
          the two air outlets comprise a rear foot zone outlet and a rear ventilating outlet, which feed, respectively, a rear foot zone duct and a rear ventilating duct, and the distribution shutter valve is displaceable between a first extreme position, which corresponds to the first distribution position, and a second extreme position which corresponds to a rear ventilating position in which the rear ventilating outlet is open, the distribution valve occupying at least one intermediate position which corresponds to a rear foot zone position in which the rear foot zone outlet is open;     the first control member includes a generally rectangular vane, which extends from the axis of rotation and which is bounded by an edge adapted to cooperate with the first wall, while the second control member includes a shell element fixed to the axis of rotation and arranged for cooperation with the second wall, which is of cylindrical form, the shell element including portions which are adapted to close or open the rear ventilating outlet and the rear foot zone outlet selectively, together with at least one radial vane which is adapted to close off the rear foot zone outlet when the distribution valve is in its rear ventilating position;     the first wall comprises a circular cylindrical portion with which the edge of the first control member co-operates when the distribution valve is in one or other of its rear distribution positions;     the apparatus has two rear foot zone outlets which flank a rear ventilating outlet;     the apparatus includes at least one rear foot zone outlet and at least one rear ventilating outlet, which are offset circumferentially and axially with respect to the axis of rotation.        

      The apparatus may include a central baffle, total or partial, which is located in the second mixing chamber whereby to define respective air streams for a right hand part and a left hand part of the cabin.  
      In particular, the central baffle may be total, whereby to divide the second mixing chamber into two chambers, each of which contains one distribution shutter valve for managing the distribution and temperature of the air streams in the right hand and left hand parts of the cabin. 
    
    
      In the following description, which is given by way of example only, reference is made to the attached drawings, in which:  
       FIG. 1  shows diagrammatically, in a cross sectional view, an apparatus according to the invention in a first embodiment;  
      FIGS.  2  to  4  show part of the apparatus of  FIG. 1 , in which the single distribution shutter valve is shown in three different regulating positions which are, respectively, a “de-icing” position, a “foot zone” position and a “ventilating” position;  
      FIGS.  5  to  8  show, respectively, four possible configurations for the “foot zone” and “ventilating” outlets of a casing which contains the single distribution shutter valve;  
       FIG. 9  is a perspective view of the single distribution shutter valve in the apparatus of FIGS.  1  to  4 ;  
       FIG. 10  is a detail of the apparatus of  FIG. 1 , showing the means for sealing the single distribution shutter valve;  
       FIG. 11  shows diagrammatically an apparatus according to a second embodiment of the invention which corresponds to a simplified design;  
       FIG. 12  shows, in perspective, a casing containing a single distribution shutter valve in a third embodiment of the invention;  
       FIG. 13  is a perspective view of the distribution shutter valve mounted in the casing of  FIG. 12 ;  
       FIGS. 14 and 15  are a diagrammatic view and a perspective view of the casing and the valve of  FIGS. 12 and 13 , in a “de-icing” position;  
       FIGS. 16 and 17  show diagrammatically and in cross section the casing and the distribution valve in a “foot zone” position, with the rear ventilating output closed;  
       FIGS. 18 and 19  are, respectively, a diagrammatic view and a view in cross section in the “foot zone” position, showing the foot zone outlet open;  
       FIGS. 20 and 21  are views similar to  FIGS. 16 and 17  in the “ventilating” position; and  
       FIGS. 22 and 23  are views similar to  FIGS. 18 and 19  in the “ventilating” position. 
    
    
      Reference is first made to  FIG. 1 , which shows a first embodiment of an apparatus according to the invention which is part of a heating and ventilating and/or air conditioning installation for a motor vehicle cabin, which has a front zone and a rear zone.  
      The apparatus comprises a casing  10  defining an upstream chamber  12  which contains, in this example, an evaporator  14  which is part of a conventional air conditioning circuit (not shown). The upstream chamber  12  is fed with fresh air (from outside and/or recirculated) which is propelled by a motorised fan unit (not shown).  
      The casing  12  also defines a heating chamber  16  which contains a heating radiator  18 , through which there passes a hot fluid, usually the coolant liquid for the engine of the vehicle.  
      The casing  10  also defines, in its upper part, a first mixing chamber  20  which has an input  22  for reheated air that comes from the heating chamber  16 , and an input  24  for the fresh air coming from the upstream chamber  12 .  
      A first mixing valve  26 , which in this example is of the “curtain” type, is mounted for pivoting movement about an axis  28 . It distributes the proportion of cold air and hot air which is fed to the first mixing chamber  20  for the purpose of producing in the latter a stream of processed air at a regulated temperature. The valve  26  is displaceable between two extreme positions, namely an open position shown in full lines, in which the mixing chamber  20  is fed with fresh air, and a closed position shown in broken lines, in which the inlet of the mixing chamber is closed, so that the fresh air is passed towards the heating radiator  18 . The valve  26  may adopt different intermediate positions for the distribution of fresh air between the inlet  24  of the mixing chamber  20  and the inlet of the heating radiator  18 .  
      The said first mixing chamber  20  feeds processed air to ducts  30 ,  32  and  34  for supplying a front zone ZAv of the cabin. The duct  30  supplies at least one de-icing/demisting vent for the windscreen, under the control of a valve  36 , while the duct  32  feeds at least one central ventilating outlet vent under the control of the valve  38 . Finally, two ducts  34  are fitted laterally on either side of the casing  10 , for supplying respective ventilating outlet vents (not shown) which are open at the two ends of the fascia panel. In consequence, the ducts  30 ,  32  and  34  enable the processed air to be passed into the front zone ZAv of the cabin.  
      The casing  10  delimits, in its lower part, an auxiliary duct  40  which is adapted to be supplied with fresh air through the upstream chamber  12  under the control of a second mixing valve  42 , which in this example is of the “curtain” type and which is pivoted about an axis  44 . The valve  42  is displaceable between two extreme positions, namely an open position shown in full lines, in which the auxiliary duct  40  is supplied with fresh air, and a fully closed position shown in broken lines, in which the inlet of the auxiliary duct  40  is closed. The valve  42  can also assume intermediate positions so as to adjust the proportion of fresh air to be distributed either towards the auxiliary duct  40  or towards the heating radiator  18  and therefore towards the heating chamber  16 .  
      A baffle  46  is placed between the valves  26  and  42 . These two latter are controlled by control devices  48  which are shown diagrammatically here.  
      The general structure of the apparatus, as described up to this point, is generally known, especially from the publications FR 2 795 683 and FR 2 795 684 which have already been mentioned.  
      In accordance with the invention, the casing  10  further delimits a second mixing chamber  50  which is located in the lower part and which is situated at the intersection of the auxiliary duct  40 , the heating chamber  60 , and two first ducts  52  and  54  which supply a rear zone ZAr of the cabin. The duct  52  is called the “rear foot zone” duct, while the duct  54  is called the “rear ventilation” duct.  
      A single distribution shutter valve  56 , which is mounted rotatably about an axis  58 , enables part of the hot air coming from the heating chamber  16  to be distributed selectively either towards the first mixing chamber  20  or towards the second mixing chamber  50 , so as to produce a stream of mixed air. In addition, the valve  56  has the function of controlling the distribution of the mixed air that comes from the second mixing chamber  50  through the above mentioned ducts  52  and  54 .  
      Reference is now made to FIGS.  2  to  4 , so as to describe more particularly the structure of the distribution shutter valve  56  and its operation. The axis of rotation  58  of the valve supports a first control member  60  and a second control member  62 . The first control member  60  comprises a vane of generally rectangular form, which extends from the axis of rotation  58  and which is bounded by an edge  64  parallel to the axis  58 . This edge  64  is arranged to cooperate with a first wall  66  which has a circular cylindrical portion  68  that extends over a limited angle (about 45° in this example). This portion  68  is joined to a baffle portion  70  which opens in an outlet face of the heating radiator  18  and which enables an imaginary line  72 , separating an upper hot air stream (arrow F 1 ) and a lower hot air stream (arrow F 2 ), to be delimited. The first wall  66  is situated in the heating chamber  16  so as to contribute to the delimitation therein of an air passage  74  for a part of the heated air (arrow F 2 ).  
      The second control member  62  is arranged to cooperate with a second wall  76 , which in this example is of circular cylindrical form and which partly delimits the second mixing chamber  50 . Two air outlets, open in this second wall  76 , consist of a “rear foot zone” outlet  78  and a “rear ventilation” outlet  80 . The outlets  78  and  80  are offset angularly with respect to the axis of rotation  58 , and they feed the ducts  52  and  54  respectively.  
      The second control member  62  comprises a shell element  82 , of cylindrical form here, which is connected to the axis of rotation  58  through radial plate elements  84 , as is best seen in the perspective view of  FIG. 9 . The term “shell element”, as used herein, is to be understood to mean a wall which is essentially non-radial with respect to the axis of rotation  58 , and which may in particular have a flat, cylindrical, or crooked form, and of which the periphery is able to close or open at least one aperture for passage of air. The second control member  62  also includes a radial vane  86  which is situated between the vane  60  that constitutes the first control member and the shell element  82 . A radial baffle  88 , which is arranged in the heating chamber  16 , extends from close to the axis  58  and serves as an abutment for the radial vane  86  in the de-icing position of  FIG. 2 .  
      The operation of the distribution shutter valve  56  will now be described in three modes which correspond to FIGS.  2  to  4 . In the de-icing mode of  FIG. 2 , the distribution vale  56  is in a first extreme position in which the control member  60  leaves the air passage  74  open and closes off access to the mixing chamber  50 . As a result, the two hot air streams F 1  and F 2  are diverted upwards and led to the first mixing chamber  20 , which supplies the front zone of the cabin. This enables benefit to be obtained from the whole of the power from the heating radiator, at the de-icing vents which are supplied through the duct  30  ( FIG. 1 ). In this position, the auxiliary duct  40  is closed by the mixing valve  42 , and in addition, the second control member  62  closes off the outlets  78  and  80 . In this connection, the shell element  82  extends over a sufficiently large angle (in this example substantially less than 90°) to close off, at the same time, the outlets  78  and  80  which are offset circumferentially. In this position, the radial vane  86  comes into engagement against the baffle  88 .  
      In the “foot zone” distribution mode of  FIG. 3 , the distribution shutter valve has pivoted through an angular fraction (which in this example is of the order of 30°) about the axis  58 , with respect to the position of  FIG. 2 , in the clockwise direction in the drawings. The edge  62  of the control member  60  comes into co-operation with one end of the cylindrical portion  68 , which thereby closes off the air passage  74 . This position corresponds to an intermediate position in which the shell element  82  of the control member  62  has opened the rear foot zone outlet  78 , while maintaining the rear ventilation outlet closed. In consequence, a part of the hot air stream (arrow F 2 ) can reach the mixing chamber  50  and become mixed in it with fresh air (arrow F 3 ), under the control of a mixing valve  42 . The stream of mixed air with adjustable temperature, which is obtained in this way, escapes through the rear foot zone outlet  78  and thus reaches the rear foot zone duct  52  as shown by the arrow F 4 .  
      In the “ventilating” distribution mode shown in  FIG. 4 , the valve has again pivoted clockwise from the previous position, and is in another extreme position. In this extreme position, the shell element  82  of the control member  62  has opened the ventilating outlet  80 , while the rear foot zone outlet  78  is closed by the radial vane  86 . As a result, the air passage  74  is still closed as in the previous position, and the hot air stream F 2  mixes with the fresh air stream F 3  to produce a stream of mixed air F 4  which passes through the ventilating outlet  80  so as to supply the rear ventilating duct  54 .  
      As can be seen in FIGS.  2  to  4 , surfaces  79  and  81  are arranged between the valve  56  and the wall  76  of the casing, so as to guarantee sealing in at least one distribution mode. In this example, the two surfaces  79  and  81  extend parallel to the axis of rotation  58 , and extend radially from the shell element  82 . The peripheries of these surfaces are offset from each other in order to permit both sealing and rotational movement of the shutter valve. The surfaces  79  and  81  enable fully sealed closing of the outlets  78  and  80  to be achieved in the de-icing mode shown in  FIG. 2 . The sealing surfaces may be replaced by other sealing means, in particular by flexible lip seals.  
      In the embodiment shown in FIGS.  1  to  4 , the outlets  78  and  80  are offset circumferentially with respect to the axis of rotation  58  on the wall  76 . Different configurations for these two outlets are shown in FIGS.  5  to  8 .  
      In the case of  FIG. 5 , the outlets  78  and  80  extend practically over the whole width of the casing  10 , as it is defined between the side walls  94  of the casing. Also shown in  FIG. 5  is the plane of symmetry S of the casing, which extends vertically and substantially halfway between the side walls  94 .  
      In the case of  FIG. 6 , the apparatus has a single foot zone outlet  78 , which is situated in the centre, together with two rear ventilation outlets  80  which are symmetrical with respect to the plane of symmetry S and which are situated close to the respective end walls  94 .  
      In the case of  FIG. 7 , the apparatus has two rear foot zone outlets  78  which are disposed symmetrically with respect to the plane of symmetry, together with a single rear ventilating outlet  80  which is situated in the centre. In the case of  FIG. 8 , the apparatus has one rear foot zone outlet  78  and three rear ventilating outlets  80 , with one outlet  80  being in the centre and two outlets  80  situated at the sides.  
      As a result, the apparatus then includes at least one rear foot zone outlet  78  and at least one rear ventilating outlet  80 , which are offset circumferentially and/or axially with respect to the axis of rotation.  
       FIG. 9  shows in perspective the structure of the shutter valve  56 . The axis  58  will be noted, as will the first control member  60  which is made in the form of a vane of generally rectangular form, and the second control member  62 , which comprises a shell element  82  mounted on two radial plate elements  84 , and, in addition, the radial vane  86 . As is shown in  FIG. 9 , it is possible to provide a central baffle  96  in the case of an apparatus in which distribution and temperature are managed separately for the left hand and right hand parts of the cabin. In this example, this central baffle is part of the shutter valve  56 .  
      Thus, the extent of the central baffle may be partial as shown in  FIG. 9 , in order to direct the processed air streams into the right hand part and the left hand part of the cabin. It is also possible that the central baffle  96  extends over the whole of the transverse cross section of the wall  76 , thereby enabling total separation to be achieved between the processed air streams in the right hand and left hand parts.  
      In this embodiment, it can be advantageous to arrange to have two shutter valves  56  of the type described above, which are arranged respectively on either side of the central baffle  96 . In that case, the central baffle  96  is preferably fixed in the mixing chamber  50 , so as to delimit two sub-chambers which are associated with the right hand and left hand parts of the cabin respectively. In another version, the central baffle may be integral with one or other of the two valves.  
      Reference is now made to  FIG. 10 , which once again shows the distribution shutter valve  56  in its de-icing position. It will be noted that this valve is provided with a number of seals, namely a lip seal  98  which constitutes the edge of the control member  60 , and three lip seals  100 ,  102  and  104  with which the shell element  82  is equipped. The lip seals  100  and  102  are situated at the ends of the shell element, while the lip seal  104  is between the seals  100  and  102 . Finally, the radial vane  86  is provided with a lip seal  106 . The main function of the lips  100 ,  102  and  104  is to provide sealing on appropriate surfaces in the de-icing mode, in a similar way to the surfaces  79  and  81  in FIGS.  2  to  4 . It may also wipe the internal walls of the casing and thereby guarantee perfect sealing in all the distribution modes. The preferred method of manufacturing this arrangement is to mould a flexible and elastic material in situ.  
      Reference is now made to  FIG. 11 , which shows a simplified version of the apparatus. In this example, the second wall  76  has a single air outlet  108  which feeds a single duct  110 , and the latter, in its turn, feeds the rear zone ZAr. The distribution shutter valve  56  is displaceable between a de-icing position (shown in full lines in  FIG. 11 ), in which the control member  60  opens the air passage  74 , while the control member  62  closes off the single air outlet. The valve  56  may also occupy a rear distribution position (represented in broken lines), in which the control member  60  closes off the air passage  74  while the second control member  62  opens the air outlet  108 . As in the preceding embodiment, the control member  60  includes a generally rectangular vane having an edge  64 . However, in the present case the first wall is limited to a baffle  112  which terminates in a terminal edge  114  with which the edge  64  of the control member  60  co-operates when the distribution valve is in its rear distribution position.  
      In the embodiment shown in FIGS.  12  to  24 , the second wall  76  and the casing (see  FIG. 12 ) has three air outlets which are offset axially along a generatrix which is parallel to the axis of rotation  58 , that is to say a rear ventilating outlet  80  which is flanked by two rear foot zone outlets  78 , these three outlets being delimited by a rectangular frame  116  and two transverse baffles  118 . The air outlets  78  delimit two respective ducts  52 , while the air outlet  80  feeds a duct  54 .  
      The distribution shutter valve  56  (see  FIG. 13 ) comprises a first control member  60  which is made in the form of a rectangular vane terminated by an edge  64  which is arranged to cooperate with a wall  66  having a circular cylindrical portion  68 , similar to that in the first embodiment.  
      The first control member  60  of the shutter valve includes a cylindrical shell element  120  which is arranged to cooperate with the above mentioned cylindrical wall  76 . The second control member  62  thus comprises a radial vane  86  similar to that in the first embodiment. The shell element  120  is attached to the vane  86  by two spacer elements  122  of circular arcuate form, which are aligned with the two baffles  118 .  
      The two spacer elements  122  serve as a support for two side baffles  124  which extend radially and which are attached to the spacer elements  122 . The shell element  120  has a central portion  126  which extends between the two spacer elements  122  from an edge  128  parallel to the axis of rotation and lying between the side baffles  124 , up to an edge portion  130  which extends over the whole axial length of the valve. The central portion 1126  is flanked by two lateral portions  132 . Each of these portions extends between an edge portion  134  which is spaced away from the end of the baffle  124 , and the edge  130 . As a result, two side apertures  136  are defined on either side of the spacer elements  122 .  
      The operation of an apparatus in this third embodiment of the invention will now be described with reference to FIGS.  14  to  23 .  
      In the “de-icing” position shown in  FIGS. 14 and 15 , the first control member  60  opens the air passage  74  while the second control member  62  closes off the two air outlets  78  and  80 . More particularly, the central portion  126  of the shell element  120  closes off the central outlet  80 , while the two side portions  132  close off the two respective side outlets  78 .  
      In the “foot zone” position shown in FIGS.  16  to  19 , the first control member  60  closes off the air passage  74 , while the second control member  62  opens one of the two air outlets, namely the two foot zone outlets  78  which are situated at the sides. The central portion  126  of the shell element  120  closes off the rear ventilating outlet  80 , while the two side portions  132  are offset and the apertures  136  are in register with the outlets  78  so as to leave them free.  
      In the “ventilating” position shown in FIGS.  20  to  23 , which constitutes another rear distribution position, the first control member  60  is still closing off the air passage  74 , while the second control member  62  opens the rear ventilating outlet  80 . On the other hand, in this position, the two side baffles  124  close off access to the rear foot zone outlets  78 .  
      The invention is of course capable of numerous modifications.