A distributor for motor-vehicle air-conditioning systems

Abstract: A distributor for motor-vehicle air-conditioning systems has a cylindrical obturator (10) rotatable in a hollow body which has apertures for the passage of the air. The cylindrical obturator has at least one flat longitudinal baffle (22) to which a shutter (36) for choking the air flow is articulated, the shutter pivoting relative to the obturator (10) against the action of resilient biasing means (40), by virtue of its engagement with a cam (28) fixed to the hollow body, so as to vary its position relative to the longitudinal baffle (22).

Description: The present invention relates to a distributor, particularly for motor-vehicle, air-conditioning systems, of the kind defined in the preamble of Claim 1. EP-A-0 296 555 discloses a distributor of this kind in which the obturator and the choking shutter are movable simultaneously in accordance with respective, different predetermined laws of motion by means of a common drive shaft and distinct, different trains of gears. The object of the present invention is to provide a rotary distributor of the above-specified type which provides for a plurality of air-flow configurations without making the structure and the production of the distributor too complicated. According to the invention, this object is achieved by means of a distributor having the features defined in Claim 1. By virtue of these characteristics, in addition to the choking effect of the obturator, which may have one or more internal baffles, the air-flow is also regulated and divided between the various air vents of the motor vehicle by means of the choking shutter which is operated by the rotation of the obturator and thus needs no additional control. Preferably, the distributor also includes an auxiliary shutter which is articulated to the housing structure in correspondence with an aperture for the passage of air about an axis parallel to the axis of rotation of the obturator and is urged into peripheral contact with the latter by resilient biasing means, the cylindrical obturator having shaped guide means on which the auxiliary shutter slides during the rotation of the obturator and which are adapted to enable the auxiliary shutter to pivot and to assume predetermined configurations for choking the air-flow corresponding to certain angular positions of the obturator. In maximum ventilation conditions, the auxiliary shutter pivots to enlarge the opening for the passage of the air and the flow of air can thus be increased. Further advantages and characteristics of the distributor according to the invention will become clear from, the detailed description which follows, provided purely way of non-limiting) example, with reference to the appended drawings, in which: Figure 1 is an exploded perspective view of the obturator of a distributor according to the invention, Figure 2 is a perspective view of the obturator of Figure 1 in the assemble configuration, and Figures 3-7 are schematic cross-sections of a distributor according to the invention in five different configurations. With reference to the drawings, a rotary cylindrical obturator, indicated 10, is adapted to be positioned in a cavity C in a housing structure A of a distributor. The housing structure A has a radial apertures 12, 16, 13, 14 and 15 for admitting air to the distributor, for supplying air to diffusers at the base of the windscreen, for connection to frontal vents directed towards the seats in the passenger compartment and, finally, for connection to lower vents adapted to direct the air-flow towards the floor of the motor vehicle, respectively. The housing structure A of the distributor may also include seats for a fan for directing the air to the apertures 12 and 16, for radiators for heating/cooling the air-flow, for auxiliary choking shutters, and for the mounting of other components of the air-conditioning system. The cylindrical obturator 10 is mounted for rotation about an axis X-X on a shaft 18 supported by the housing structure A and has a pair of circular transverse baffles 20 and 21, a longitudinal baffle 22 which connects the transverse baffles 20, 21 and is parallel to the shaft 18, and a wall 24 with a cylindrical surface coaxial with the shaft 18 and located on the opposite side of the shaft from the longitudinal baffle 22. The longitudinal baffle 22 and the wall 24 with the cylindrical surface have respective ends 22a and 24a which extend beyond the transverse baffles 20 and 21. At their centres, the latter have a bush 20a and a hole 21a respectively, coaxial with the shaft 18. The whole 21a in the transverse baffle 21 is for the insertion of a tubular support element 26 which is keyed to the fixed shaft 18 and carries a can 28 at its end adjacent the transverse support 21. The ends 22a of the longitudinal baffle 22 are also connected by means of triangular walls 30 to respective auxiliary bushes 32 and 33 coaxial with the shaft 18. The auxiliary bush 33 has an outer surface in the form of a gear for rotating the obturator 10. Obviously, the latter may be rotated by other means. Between the transverse baffles 20 and 21, the longitudinal baffle 22 has two articulation seats 34 in which a substantially rectangular choking shutter 36 with a lateral follower pin 38 for cooperating with the lateral surface of the cam 28 is articulated about an axis Y-Y parallel to the axis of rotation X-X of the obturator 10. Two pin springs 40 coaxial with the articulation seats 34 are interposed between the choking shutter 26 and the longitudinal baffle 22 for urging the shutter 36 into abutment with the longitudinal baffle 22. An auxiliary shutter 42 is provided in correspondence with the air-inlet aperture 12 of the distributor and is articulated to the housing structure A about an axis parallel to the axis of rotation X-X of the obturator 10. A spring 43 is interposed between the auxiliary shutter 42 and the housing structure A for urging the auxiliary shutter into contact with peripheral edges E of the circular transverse baffles 20, 21. Each transverse baffle has a recess 45 in its circular edge adjacent the longitudinal baffle 22 to enable the auxiliary shutter 42 to pivot when the obturator 10 assumes the configuration shown in Figure 5, as will become clear from the following description. When the distributor is in the operative configuration, the obturator 10 can be rotated by the gear 33, in known manner, by means of a manual, electrical, or pneumatic device. Figure 3 shows a first configuration of the distributor, in which the longitudinal baffle 22 prevents the air-flow from being directed through the apertures 14 and 15 to the respective frontal and lower vents. In this configuration, the free edge of the auxiliary shutter 42 is in contact with the peripheral edges of the transverse baffles 20 so as to choke the cold air 1 flowing in through the aperture 16. The choking shutter 36 is kept in a position substantially parallel to the longitudinal baffle 22 by the cooperation between the follower pin 38 and the lateral surface of the cam 28 so that it does not interfere with the hot air-flow 2 and/or the cold air-flow 1 (in the case of a mixture) which is directed entirely towards the diffusers or vents at the base of the windscreen (the so-called defrosting configuration). Figure 4 shows a second configuration of the distributor, which can be attained from the configuration of Figure 3 by an anticlockwise rotation of the obturator 10 (with reference to Figures 3 and 7) through approximately 45°. In this configuration, the longitudinal baffle 22 obstructs the hot air-flow 2 and/or the cold air-flow 1 to the aperture 14, directing it towards the lower vents and towards the diffusers at the base of the windscreen. In this configuration, the follower pin 38 of the choking shutter 36 is disengaged from the lateral surface of the cam 28 and is urged, under the action of the pin springs 40, against the central shaft 18 so that it is positioned substantially perpendicular to the longitudinal baffle 22. It thus divides the air-flow correctly between the apertures 13 and 15. The configuration shown in Figure 5 is reached after a further anticlockwise rotation of the obturator 10 through an angle of approximately 90° and corresponds to the maximum cold air-flow 1 and/or hot air-flow 2 into the distributor since, in this configuration, the auxiliary shutter 42 can lie against the longitudinal baffle 22, by virtue of the presence of the shaped recesses 45, so as to enlarge the opening in correspondence with the aperture 16. This configuration may be selected in order to achieve a maximum flow of cold air. The flow of cold air 1 through the aperture 16 alone (in this case, the aperture 12 is obstructed by an auxiliary shutter, not shown) is directed to the central vents (aperture 14) and the side vents. The longitudinal baffle 22 completely obstructs the aperture 13, whilst the wall 24 with the cylindrical surface completely obstructs the aperture 15. The choking shutter 36 is also kept parallel to the longitudinal baffle 22 by virtue of the engagement between the follower pin 38 and the cam 28. Clearly, in this configuration, the maximum air-flow is conveyed to the frontal vents. The fourth configuration shown in Figure 6 corresponds to the delivery of the hot air-flow 2 and/or the cold air-flow 1 to the frontal and lower vents. In this configuration, the longitudinal baffle 22 substantially chokes the air-flow to the aperture 13, whilst the choking shutter 36, which is urged against the central shaft 18 by the springs 40 and is therefore in a position sustantially perpendicular to the longitudinal baffle 22, achieves an optimal distribution of the air-flow to the apertures 14 and 15. In the last configuration illustrated in Figure 7, which corresponds to the delivery of the entire hot air-flow 2 and/or cold air-flow 1 to the lower vents, the longitudinal baffle 22 obstructs the apertures 13 and 14. Clearly, positions of the obturator 10 intermediate the five basic configurations described above afford the distributor a wide range of operating conditions. Moreover, with the distributor according to the invention, the side air vents can be supplied independently of the central vents.

Claims: A distributor, particularly for motor-vehicle air-conditioning systems, comprising a housing structure (A) with apertures (12-16) for the passage of the air, a cylindrical obturator (10) which is rotatable in the housing structure (A) and is adapted to choke the flow of air through the apertures, and means for rotating the obturator (10), whereby a choking shutter (36) is articulated to the obturator (10) about an axis (Y-Y) characterised in that the axis (Y-Y) is substantially parallel to the axis of rotation (X-X) of the obturator (10) and has follower means (38) for cooperating with cam means (28) supported by the housing structure (A) in order to vary the angular position of the shutter (36) relative to the obturator (10) when the obturator (10) is rotated. A distributor according to Claim 1, characterised in that it includes an auxiliary shutter (42) which is articulated to the housing structure (A) in correspondence with an aperture (12) for the passage of air about an axis parallel to the axis of rotation (X-X) of the obturator (10) and is urged into peripheral contact with the latter by resilient biasing means (43), the cylindrical obturator (10) having shaped guide means (20, 45) on which the auxiliary shutter (42) slides during the rotation of the obturator (10) and which are adapted to enable the auxiliary shutter (42) to pivot and to assume certain configurations for chocking the air-flow corresponding to certain angular positions of the obturator (10). A distributor according to Claim 1, characterised in that the obturator (10) comprises: at least one pair of substantially circular transverse baffles (20, 21) coaxial with a central shaft (18) and rotatable about the latter, a flat longitudinal baffle (22) which connects the transverse baffles (20, 21) and is parallel to the central shaft (18), a wall (24) with a cylindrical surface on the opposite side of the central shaft (18) from the longitudinal baffle (22) and coaxial with the central shaft (18), a cam (28) supported by the structure (A) between the transverse baffles (20, 21), a substantially rectangular choking shutter (36) articulated to the longitudinal baffle (22) of the obturator (10) and having a lateral follower pin (38) for cooperating with the cant (28) when the obturator (10) is rotated, resilient means (40) being interposed between the longitudinal baffle (22) and the choking shutter (36) for leaping the follower pin (38) in contact with the cam (28). A distributor according to Claims 2 and 3, characterised in that the guide means for the auxiliary shutter (42) are constituted by edges (E) of the transverse baffles (20, 21) , the latter having shaped recesses (45) for enabling the auxiliary shutter (42) to pivot inwardly of the obturator (10) when the obturator (10) is in a predetermined range of angular positions relative to the housing structure (A). A distributor according to Claim 4, in which the housing structure (A) has at least four radial apertures (12, 13, 14, 15) which communicate respectively with an opening for admitting air to the distributor, with diffusers for diffusing air into the region at the base of the windscreen, with frontal air vents, and with lower air vents which are directed substantially towards the floor of the motor vehicle, characterised in that, as the cylindrical obturator (10) rotates about its axis (X-X), it can assume: a first configuration in which the longitudinal baffle (22) obstructs the flow of air through the frontal and lower vents and directs it entirely towards the diffusers at the base of the windscreen, the choking shutter (36) being positioned substantially parallel to and in contact with the longitudinal baffle (22) in this configuration, a second configuration in which the longitudinal baffle substantially obstructs the flow of air to the frontal vents and directs it towards the lower vents and the diffusers at the base of the windscreen, the choking shutter (36) being positioned substantially perpendicular to the longitudinal baffle (22) in this configuration so as to divide the two air-flows, a third configuration in which the longitudinal baffle (22) obstructs the flow of air to the diffusers at the base of the windscreen and in which the wall (24) with the cylindrical surface obstructs the flow of air to the lower vents, the choking shutter (36) being positioned substantially parallel to and in contact with the longitudinal baffle (22) in this configuration, and the auxiliary shutter (42), which is disposed in correspondence with the aperture (16) for admitting air to the distributor, being positioned substantially parallel to and in contact with the longitudinal baffle (22), by virtue of the presence of shaped recesses (45) in the transverse baffles (20, 21), in order to convey a greater flow of air to the front vents, a fourth configuration in which the longitudinal baffle (22) partially obstructs the flow of air to the diffusers at the base of the windscreen and directs it towards the front and lower vents, the choking shutter (36) being poisitioned substantially perpendicular to the longitudinal baffle (22) in this configuration so as to divide the two air-flows, and a fifth configuration in which the longitudinal baffle (22) obstructs the flow of air to the diffusers at the base of the windscreen and to the frontal vents and directs it entirely to the lower vents.

Inventors: AIMONE ADELIO, AIMONE, ADELIO
Applicants: BORLETTI CLIMATIZZAZIONE, BORLETTI CLIMATIZZAZIONE S.R.L.
Application year: 1990
Main classification: B60H1
IPC codes: B60H1