FR2791611A1 - AIR CONDITIONER FOR VEHICLES WITH SLIDING AIR MIXING DOOR - Google Patents

Abstract

The invention relates to an air conditioner for vehicles with a sliding air mixture door. The air conditioner comprises two heat exchangers (7, 8) and an air mixture door (11) arranged in a duct. (2), said air mixing door being able to slide in a transverse direction with respect to a hot air path and a cold air path, under the action of a sliding mechanism (21), so as to adjust the air flow rates passing through said respective paths of hot and cold air. The sliding mechanism comprises a sliding cord (23) connected to said door (11) and a spring (25) connected at one end to said cord (23) and at its other end to said door (11), at least one part of said spring being disposed inside a face (11a) of the door which faces towards the air flow direction.

Description

AIR CONDITIONER FOR VEHICLES WITH MIXING DOORS

SLIDING AIR.

  The present invention relates to an air conditioner for vehicles and more particularly, an air conditioner comprising a sliding type air mixing door for adjusting the ratio of

  mixture of hot and cold air.

  A conventional air conditioner for vehicles as shown in Figure 5 attached is described below. A blower 102, an evaporator 103 serving as a cooling device and a radiator 104 serving as a heating device are arranged in this order in an air duct 101. A rotary type air mixing damper 105 is mounted upstream of the radiator 104. An air flow enters through a suction orifice 106 and passes through the evaporator 103. The ratio of the air flow which passes through the radiator to the air flow which bypasses it is regulated by the mixture register d 105. The air conditioning temperature flow is discharged inside a vehicle via one or more air discharge orifices chosen from a discharge orifice in DEF 107 mode, a discharge port in WIND 108 mode and one discharge port in VENT mode

FOOT 109.

  As shown in Figure 5, a space to allow the rotational movement of the air mixing damper 105 must be left free between the evaporator 103 and the radiator 104, but this space

  increases the size of the air conditioner.

  To meet the recent requirement to reduce the size of an air conditioner, a structure comprising a sliding type air mixing door may be provided in place of the rotary type air mixing damper described. above. Sliding air mixing door is described in Japanese patent publications

JP-A-10-35 246 and JP-A-8-282 248.

  In Japanese patent publication JP-A-10-35,246, a lever engages an air mixing door and controls it directly. However, this drive mechanism occupies a space, which prevents reducing the size of the structure. In addition, since the lever is actuated towards a position where it can come into engagement with the door, its movement is restricted, which limits the freedom of design of the mechanism. In addition, for guiding the mixing door, there is provided a groove which is divided into a plurality of guide grooves, which also occupy a space, so that the

  reduction in the size of the structure is limited for this other reason.

  In Japanese patent publication JP-A-8-282 248, a link lever mechanism controls the sliding of an air mixing door. This mechanism is complex and increases the size of the air conditioner because it extends into the air flow mixing zone. In addition, this linkage lever mechanism

  complicated presents a poor degree of design freedom.

  To overcome these drawbacks, the applicant of the present invention has proposed an improved mechanism which is the subject of Japanese patent application 10-115 993, prior to the present application. As shown in the attached FIG. 6, which illustrates this mechanism, the air mixing door 113, which is mounted between an evaporator 111 and a heating radiator 112 in an air line 110, is driven in sliding movement by a sliding cord 114 itself driven by a pulley 116, a spring

  pull 115 being inserted into the cord 114 to tension it.

  Smooth sliding movement of the door 113 is made possible by the tension provided by the spring 115 and the size reduction of the sliding mechanism is possible. In addition, because this mechanism is simple, its degree of design freedom is important. However, in this improved mechanism, taking into account the location of the tension spring 115, there is a risk, when the cord 114 is driven, that the tension spring 115 and the drive pulley 116 will interfere with each other. To avoid such discomfort,

  it may be necessary to limit the sliding stroke of the door 113.

  An object of the present invention therefore consists in producing an air conditioner for vehicles comprising a sliding mechanism for an air mixing door, which makes it possible to enlarge the sliding stroke of the door and to ensure sliding in

  softness of it, while having a reduced size.

  To achieve these and other objects, the invention provides an air conditioner for vehicles which includes several heat exchangers and an air mixing door mounted in a pipe. The air mixing door slides in a transverse direction with respect to a hot air path and a cold air path formed in the pipe, by the action of a sliding mechanism. The air mixing door regulates the air flows passing through the respective paths of hot and cold air, by means of its sliding. The sliding mechanism comprises a sliding cord constituted by a cable or a belt which is connected to the door, a cord driving pulley and means for tensioning the cord. The tensioning means comprise a spring connected to the cord by its first end and connected to the door by its other end. At least part of the spring is housed inside an area of the face of the door which faces the direction of air flow in the pipe. The spring can be a tension spring or a torsion coil spring. At least part of the spring can be arranged in a

  spring housing which is formed inside said face of the door.

  The spring housing can be constituted by a cavity formed on

said face of the door.

  Preferably, said heat exchangers comprise a cooling device and a heating device and the air mixing door is disposed between these two devices. In a preferred embodiment, the air mixing door is made, not with

  a soft material such as a film, but with a rigid material.

  The air mixing door can be guided along a guide groove during its sliding. Preferably, the guide groove is shaped so that the door is guided away from one of said heat exchangers when it slides and can come substantially into contact with the heat exchanger when its sliding movement is finished. The guide groove extends continuously from a position corresponding to a first end of the sliding path of the door to a position corresponding to a

  second end of said sliding path.

  In such an air conditioner for vehicles according to the present invention, since at least part of the spring intended to supply a tension to the cord is arranged inside an area of the face of the air mixing door , the travel movement of the spring can be fully absorbed or almost in the travel movement of the sliding door. This eliminates any risk of interference between the spring and the cord drive pulley. In addition, since this risk of interference no longer exists, the degree of freedom regarding the location of the spring and the formation of the spring can be significantly increased.

spring mechanism.

  Although the size of the door sliding mechanism and that of the air conditioner assembly can be reduced, a large stroke of the door sliding movement can be ensured without inconvenience. Thanks to the lengthening of this stroke, it is easier to obtain a more precise positioning of the door in a target position which depends on the desired conditioning mode. In addition, since all risk of interference between the spring and the drive pulley is eliminated, an appropriate tension is constantly supplied to the cord in a constant stable condition, so that the door slides with a regular movement over the whole of her

race.

  Other purposes, features and advantages of this

  invention will become apparent from the detailed description below of modes of

  preferred embodiments of the present invention, given by way of nonlimiting examples, with reference to the appended drawings in which: FIG. 1 is a schematic sectional view of an air conditioner for vehicles according to a first embodiment of the invention; 'invention; Figure 2 is a vertical, partial and enlarged sectional view of the air conditioner of Figure 1; Figure 3 is an enlarged perspective view of a portion of the air mixing door of the air conditioner of Figure 1; Figure 4 is a perspective view of the air mixing door according to a second embodiment of the invention; Figure 5 is a schematic sectional view of a conventional air conditioner for vehicles; and FIG. 6 is a partial vertical section view of an air conditioner for vehicles according to a solution proposed by the

  Applicant, prior to the present invention.

  Figures 1 to 3 show an air conditioner for vehicles according to a first embodiment of the invention. The air conditioner 1 comprises an air duct 2 provided, on the intake side, with an exterior air intake port 3, an interior air intake port 4 and a damper 5 to adjust the intake ratio between the outside air and the indoor air. A blower 6 is mounted in the pipe 2 downstream of the intake orifices 3 and 4 for

  suck in air and discharge the sucked air downstream of the pipe.

  A cooling device constituted by an evaporator 7 and a heating device constituted by a radiator 8 are mounted in this order in the pipe, in positions located downstream by

  relative to the blower 6. The air flow path which passes

  above the radiator 8 constitutes a cold air flow path 9.

  This flow of cold air passes through the evaporator 7. The air flow path which passes through the evaporator 7 and the radiator 8

  constitutes a hot air flow path 10.

  A sliding air mixing door 11 is provided between the evaporator 7 and the radiator 8. In this embodiment, the door 11 is located immediately upstream of the radiator 8. The door slides in a direction transverse to the path cold air flow 9 and the hot air flow path 10 to adjust the air flow rates passing through these paths, according to the desired conditioning mode. Respective air discharge ports, such as a discharge port in DEF mode 12, a discharge port in WIND mode 13 and a discharge port in FOOT mode 14, are formed downstream in line 2. Registers 15 and 16 regulate air circulation

  blown from the discharge ports 12, 13 and 14.

  As shown in FIGS. 1 and 2, the door 11 is driven in sliding movement by a mechanism 21 formed by a cord 23 which is driven by a driving pulley 24. The cord slides on a sliding path when it is driven. The driving pulley 24 can be rotated by a motor actuating device or by a connecting rod connection mechanism (not shown). Although in this embodiment, the cord 23 consists of a cable, it can consist of a strap. One end of the cord 23 is connected to the upper end of the door 11, while its other end is connected to a vertically middle portion of the door by means of a tension spring 25 which stretches the cord with tension appropriate. Preferably, the air mixing door 11 is

made of rigid material.

  In this embodiment, a spring housing 28 is provided on one of the faces 11a and 11b of the door 11 which are turned towards the direction of air flow in the pipe 2, as shown in the Figure 3. In the embodiment shown, the spring housing is formed on the face 1a in the form of a hollow cavity, but it may as well be formed on the face 1 lb. At least part of the tension spring 25 is disposed in the spring housing 28. In the embodiment shown, all of the tension spring 25 is disposed in the spring housing 28. One end of the tension spring 25 is connected to a connection portion 29 located at a vertically central position of the door 11, while its other end is connected to one end of the cord 23. The cord passes through a hole 30 defined at the bottom of the spring housing 28. The vertical length of the spring housing is chosen to allow the tension spring 25 to stretch to provide the desired tension in the cord. The door 11 slides vertically in FIG. 1 by the action of the cord 23 along its sliding path. During its sliding, it is guided along a guide groove 26 by pins 27 which project on the two lateral sides of the door and which are received in the guide groove 26. As shown in FIG. 2 , the guide groove 26 comprises an upper guide groove 26a and a lower guide groove 26b, the lower end of the upper guide groove 26a being connected to the upper end of the lower guide groove 26b. The guide grooves 26a and 26b are in the form of a polygonal line, such that the door moves away from the side of the radiator 8 when it slides up or down and comes into contact with or approaches the side. of the radiator 8 when it has finished sliding. Thus, when the door 11 slides, it does not come into contact with the radiator 8, which increases the durability of these two elements, and when it has finished sliding, it presses on the side of the radiator, thus closing the path

air flow.

  In this air conditioner according to the first embodiment, since the air mixing door 11 is sliding, the space required for its operation can be greatly reduced compared to that

  of the conventional rotary type door shown in FIG. 5.

  In addition, the space required for the sliding mechanism 21 is also greatly reduced because it consists of a cord 23, such as a cable or a strap. Consequently, the size of the sliding mechanism itself and that of the entire air conditioner can be greatly reduced. In addition, since the cord 23 is continuously tensioned with an appropriate constant tension by the tension spring 25, this tension can always be maintained at a desired value. We can therefore ensure correct and regular operation of the cord

  as well as a regular sliding of the door.

  In addition, since the tension spring 25 is disposed inside the face 11a of the door 11, there is no risk of hampering the driving pulley 24 over the entire sliding stroke of the door. It is therefore easy to ensure a suitable stroke for the sliding movement of the door 11 without any drawback. A positioning of the door depending on the air conditioning mode

  desired can therefore be obtained easily and precisely.

  FIG. 4 represents an air mixing door of an air conditioner according to a second embodiment of the present invention. In FIG. 4, a helical torsion spring 33 is arranged inside a zone of the face 31a of the door 31. The faces 31a and 31b are turned towards the direction of air flow in the pipe 2 A first end of the torsional coil spring 33 is engaged in an engagement portion 34 provided on the face 3a and its other end is connected to one end of a sliding cord 32 via a portion mobile connection 35. A guide portion 36 for guiding the cord is provided at the lower part of the face 31a. Pegs 37 for guiding the door 31 along guide grooves (not shown) are fixed to

the lateral sides of the door.

  In this second embodiment, the helical spring of

  torsion 33 continuously supplies an appropriate tension to cord 32.

  Since the spring is arranged inside the face 31 la of the

  door, it does not interfere with the drive pulley over the entire travel of the door.

  This results in regular operation of the door and an increased degree of design freedom for the sliding mechanism. In addition, the desired suitable operating stroke of the door can

be easily increased.

  Although embodiments of the present invention have

  been described in detail, the scope of the invention is not limited thereto.

  Those skilled in the art will understand that various modifications may be

  carried out without departing from the scope of the invention.

Claims (10)

  1. Air conditioner (1) for vehicles, characterized in that it comprises several heat exchangers (7, 8) and an air mixing door (11, 31) arranged in a pipe (2), said air mixing door which can slide in a transverse direction with respect to a hot air path (10) and a cold air path (9), under the action of a sliding mechanism (21), so as to regulate air flow rates passing through said respective paths of hot and cold air (10, 9), said sliding mechanism (21) comprising a sliding cord (23, 32) connected to said door ( 11, 31) and means for tensioning said cord, said tensioning means comprising a spring (25, 33) connected by a first end to said cord (23, 32) and by its other end to said door (11 , 31), at least part of said spring (25, 33) being disposed inside an area of a face (1a) of the door which is turned e in the direction   of air flow in said pipe.   2. Air conditioner (1) according to claim 1, characterized in   that said cord (23, 32) is constituted by a cable or a strap.   3. Air conditioner (1) according to one of claims 1 or 2,   characterized in that said spring (25) is a tension spring.   4. Air conditioner (1) according to one of claims 1 or 2,   characterized in that said spring (33) is a helical torsion spring. 5. Air conditioner (1) according to any one of   previous claims, characterized in that at least part   said spring (25, 33) is disposed in a housing (28) which is formed   inside said face (la) of the door (11, 31).   6. Air conditioner (1) according to claim 5, characterized in that said housing (28) is constituted by a cavity which is defined   on said face of the door (11, 31).   7. Air conditioner (1) according to any one of   previous claims, characterized in that said heat exchangers   heat are constituted by a cooling device (7) and a heating device (8) and in that said door (11, 31) is arranged between these two devices.   8. Air conditioner (1) according to any one of   previous claims, characterized in that it comprises a groove   guide (26) along which slides said door (11, 31).   9. Air conditioner (1) according to claim 8, characterized in that said guide groove (26) is shaped such that the door (11, 31) is guided to move away from one of said exchangers heat when it slides and comes into substantial contact with   the heat exchanger when its sliding is finished.   10. Air conditioner (1) according to claim 8 or 9, characterized in that said guide groove (26) extends continuously from a position corresponding to a first end of a sliding path of said door (11, 31) to a position   corresponding to a second end of said path.