JPH06179317A - Air path changeover device - Google Patents

Abstract

PURPOSE:To prevent dimention dispersion and dimension variation of respective parts of a membraneous member, a filamentous member or the like from being affect of on the operation of the membraneous member. CONSTITUTION:A connecting shaft 23 connected to a winding shaft for a film damper (a membraneous member) in its state of a turn stopper is inserted rotatably into the shaft hole of No.1 pulley 22 for a wire (a filamentous member) 24. Because a pin 23e on the connecting shaft 23 side abuts on rising portions 27b, 27c on the pulley 22 side under this inserted condition, the rotatably range of the pulley 22 is limited within a specified angle. A torsion coil spring 25 fitted on a small diameter shaft part 23b of the connecting shaft 23 has its hook 25a on one side locked by the connecting shaft 23 and has its hook 25b on the other side locked by a slit formed on the pulley 22 side the torsion coil spring 25 causes the pulley 22 to be energized and held within said rotatable range by resisting against the tension, exerted on the wire 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air passage switching device in which the opening of an air passage portion is changed according to the movement of a film member, and more particularly, it is connected to both ends of the film member. The present invention relates to an air passage switching device configured to connect a pulley to each winding shaft and to hang a filamentous member between the pulleys in order to rotate the paired winding shafts in an interlocking state.

[0002]

2. Description of the Related Art In recent years, in an air passage switching device for an automobile air conditioner, a blower mode switching damper, an air mix damper, and the like provided in a duct case are made of a film material made of a flexible material such as a plastic film. It is considered that the structure is simplified and the overall weight and size are reduced by configuring the film damper as used.

In this type of air passage switching device, both ends of the film damper are connected to different winding shafts in order to move the film damper in the forward and reverse directions.
Each winding shaft is configured to be supported by the duct case, and in order to rotate the winding shafts in a linked state,
A pulley is connected to each winding shaft, and a wire, for example, a wire, is hung between the pulleys.

[0004]

In the air passage switching device having the above-mentioned conventional structure, the take-up shaft and the pulley are integrally connected. Therefore, the dimensional variation of each part such as the film damper, wire, and duct case at the time of manufacturing, and the dimensional change of each part due to the ambient temperature change at the time of actual use are caused by the operating force and stress of each part required for moving the film damper. It is inevitable that the operation of the film damper is adversely affected, such as an increase in the film thickness or a looseness of the film damper, which is an unsolved problem.

In view of the above-mentioned circumstances, the present invention focuses on the phenomenon that the dimensional variation of each component due to the dimensional variation of each component and the ambient temperature change appears as the tension change of the thread member suspended between the pulleys. The purpose is to add a function to absorb the tension change of the thread-like member, so that the dimensional change of each part due to the dimensional variation of each part and the ambient temperature change adversely affects the operation of the film-like member. An object of the present invention is to provide an air passage switching device that can prevent the occurrence of the above-mentioned problems.

[0006]

In order to achieve the above-mentioned object, the present invention provides a film-like member for changing the opening of the air passage portion in response to the movement of the air passage portion while facing the air passage portion. , A pair of take-up shafts connected to both ends of the film-like member for taking up the film-like member according to the rotation of the film-like member, a pair of pulleys respectively connected to the respective take-up shafts, and wound between these pulleys. The air passage switching device, comprising: a filamentous member that rotates the respective take-up shafts in an interlocking state, and a drive unit that rotationally drives at least one of the take-up shafts to move the film-like member. Of at least one of the pulleys is rotatably connected to the corresponding winding shaft, and the film-shaped member, the winding shaft, the thread-shaped member, and the pulley are assembled in a predetermined position. For pulleys that can rotate And it is obtained by a configuration in which the spring means exerting a spring force.

In this case, a rotation restricting means for restricting the rotatable range of the pulley within a predetermined angle is additionally provided, and then the spring means is provided with the film member, the winding shaft, the thread member and It is also possible to dispose the pulley so as to be positioned within the rotatable range against the tension acting on the thread-like member when the pulley is installed in a predetermined position.

[0008]

[Operation] A film-shaped member whose both ends are wound around a pair of winding shafts,
There are dimensional variations in each component such as the thread-shaped member that is stretched between a pair of pulleys that are connected to each winding shaft, the member that is provided to support each winding shaft, and these components are assembled and integrated. If the dimensions of each component itself and the dimensions between the winding shafts are distorted, or if the dimensions of the above components change with the ambient temperature when they are assembled together, then Changes appear as changes in tension of the film member and the thread member.

In this case, according to the first aspect of the present invention, since the spring means for applying the spring force to the pulley connected to the winding shaft in a rotatable state is provided, the tension of the thread member is increased. At the time of increase, the pulley is rotated in the direction to reduce the tension of the thread member against the spring force of the spring means, and when the tension of the thread member is decreased, the pulley is driven by the spring force of the spring means. Will be rotated in the direction of increasing the tension of the.

As described above, as the tension of the thread-shaped member changes, the pulley is rotated in the direction to absorb the tension change of the thread-shaped member. As a result, the operating force required to move the film-shaped member increases or each part is moved. The increase in stress and the loosening of the film-shaped member are suppressed, and the situation in which the dimensional variation and dimensional change of each component adversely affect the operation of the film-shaped member is prevented in advance. .

According to a second aspect of the present invention, the rotatable range of the rotatable pulley is regulated within a predetermined angle by the rotation regulating means, and the spring means is the pulley. Is arranged so as to be positioned within the rotatable range against the tension acting on the thread member, the torque acting on the spring means from the thread member is allowed by the spring means (torque transmission). Even when the capacity is exceeded, there is no risk that the transmission of the rotational force between the winding shaft and the pulley will be hindered.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an automobile air conditioner will be described below with reference to the drawings. In FIG. 10 showing a schematic cross-sectional structure of an automobile air conditioner, a defroster outlet 3 is formed on the most downstream side of a duct case 2 having a blower 1 at the most upstream side, and the outlet 3 Face outlet 4 and foot outlet 5 on both sides
Are formed. Each of the air outlets 3 to 5 corresponds to an air passage portion of the present invention, and the defroster air outlet 3 is provided to blow out conditioned air toward the windshield.
The face outlet 4 is provided to blow out conditioned air toward the upper body of the occupant, and the foot outlet 5 is provided to blow out conditioned air to the feet of the occupant.

In the duct case 2, an evaporator 6 for cooling air is arranged at a portion near the blower 1, and
A heater core 7 is arranged on the downstream side of the evaporator 6 and on the bottom side of the duct case 2. In this case, the heater core 7 is provided in a form orthogonal to the evaporator 6, so that the air mix ventilation passage 8 and the bypass ventilation passage 9 (each of which is provided in the duct casing 2 are separated by the heater core 7). Equivalent to the air passage part of the invention)
Is formed.

The air mix ventilation passage 8 is located on the upstream side of the heater core 7, and the air passing therethrough is heated by passing through the heater core 7 to become warm air. Also,
The bypass ventilation passage 9 is provided to allow the air cooled by the evaporator 6 to flow without passing through the heater core 7.

The winding shafts 10 and 1 are respectively provided at a position in the duct case 2 facing the lower end of the air mix ventilation passage 8 and a position facing the upper end of the bypass ventilation passage 9.
1 is rotatably supported. Both ends of an air-mix film damper 12 corresponding to the film-shaped member of the present invention are connected to the winding shafts 10 and 11, and the film damper is rotated in accordance with the forward and reverse rotations of the winding shafts 10 and 11. 12
Can be selectively moved in the forward and reverse directions.
In addition, one winding shaft 10 is a motor 1 having a built-in reduction mechanism.
3 (corresponding to the driving means in the present invention), and the other winding shaft 11 is rotated by the motor 13 via a pulley (not shown) and a wire as a thread member. ing.

The film damper 12 is made of, for example, a flexible polyethylene resin, and the film take-up shaft 10,
It is provided so as to correspond to both the air mix ventilation passage 8 and the bypass ventilation passage 9 by being bridged between 11 and to be in contact with the end face of the heater core 7 on the evaporator 6 side.

Although not shown, an opening is formed at a predetermined position of the film damper 12, and this opening is
By selectively facing one or both of the air mix ventilation passage 8 and the bypass ventilation passage 9 according to the movement of the film damper 12, the opening degree of the ventilation passages 8 and 9 is changed. Therefore, the ratio of the amount of air blown through the air mix air passage 8 and the amount of air blown through the bypass air passage 9 can be arbitrarily adjusted according to such a change in the opening degree. In addition, a plate-shaped damper 1 for bypassing the cold air is provided in a portion above the winding shaft 11 in the duct case 2.
4 is provided, and this plate-shaped damper 14 is rotated to the position shown by the chain double-dashed line in the figure at the time of maximum cooling to guide the cooling air by the evaporator 6 to the defroster outlet 3 and face outlet 4 sides. It is composed.

On the other hand, at the position facing the blower 1 side end of the face outlet 4 and the position facing the heater core 7 side end of the foot outlet 5 in the duct case 2, the take-up shaft 15, 16 is rotatably supported.
Guide roller shafts 17 and 18 are provided in the duct case 2 at intermediate positions between the defroster outlet 3 and the face outlet 4 and at intermediate positions between the defroster outlet 3 and the foot outlet 5, respectively. It is rotatably supported in a state in which a predetermined gap is formed between the two. The winding shafts 15 and 16 are connected to both ends of a film damper 19 for switching the blowing mode, which corresponds to the film-shaped member in the present invention. The damper 19 can be selectively moved in the forward and reverse directions.

The film damper 19 is made of, for example, a flexible polyethylene resin and has the winding shaft 15,
It is provided so as to be movable in a state of facing the defroster outlet 3, the face outlet 4, and the foot outlet 5 by being hung across the space between the guide roller shafts 17 and 18 and the duct case 2. Has been.

As shown in FIG. 9, the film damper 19 has a plurality of first openings 19a selectively opposed to the face outlet 4, a defroster outlet 3 and a foot outlet 5 selectively. The plurality of second openings 19b facing each other are formed in the moving direction of the film damper 19 so as to be separated from each other with a predetermined dimension. As a result, the first opening 19a is selectively opposed to the face outlet 4 in accordance with the movement of the film damper 19, and the second opening 19b is provided to one or both of the defroster outlet 3 and the foot outlet 5. By selectively opposing to each other, the openings of the outlets 3 to 5 can be changed, and a plurality of types of air blowing modes can be obtained according to such changes in the openings.

FIG. 9 is an exploded perspective view schematically showing a part of the main part of FIG. 10 omitted to facilitate understanding of parts related to the gist of the present invention. Therefore, in the following, description will be given with reference to FIG.

That is, the winding shaft 15 is connected at its one end to a motor 20 (corresponding to a driving means in the present invention) having a speed reduction mechanism built therein, and at the other end thereof, a first pulley 21 integrated with the motor. It is connected via the shaft portion 21a. In addition, the winding shaft 1
6, the second pulley 22 is a connecting shaft 23 which is a separate component from the second pulley 22.
A wire 24, which is a thread-like member, is hung between the pulleys 21 and 22.
In this case, the winding direction of the wire 24 on the first pulley 21 and the second pulley 22 is opposite to the winding direction of the film damper 19 on the winding shafts 15 and 16 corresponding to the pulleys 21 and 22, respectively. It is set.

Therefore, when the winding shaft 15 and the first pulley 21 are rotated in the direction of arrow A in FIG. 9 by the motor 20, the film damper 19 is wound around the winding shaft 15 and is wound up. The shaft 16 and the second pulley 22 are also rotated in the arrow A direction, and accordingly, the second pulley 22 is rotated.
Will wind up the wire 24 sent out from the first pulley 21. On the contrary, the winding shaft 1 is driven by the motor 20.
When the first pulley 21 and the first pulley 21 are rotated in the opposite direction to the arrow A, the second pulley 22 and the take-up shaft 16 move in the opposite direction to the arrow A as the wire 24 is wound around the first pulley 21. Then, the film damper 19 is wound around the winding shaft 16. As a result,
The film damper 19 can be reciprocated in the forward and reverse directions by rotating the motor 20 in the forward and reverse directions.

Now, the structure of the second pulley 22 and the parts related thereto will be described below with reference to FIGS. That is, the connecting shaft 23 has a shape in which a main body portion 23a having a circular cross section and a shaft portion 23b having a smaller diameter than the main body portion 23a are integrally formed. In this connecting shaft 23, a base end side portion of the main body portion 23a is formed in a substantially D-shaped cross section, and this portion is formed in an end surface of the winding shaft 16 in a substantially cross sectional D shape.
By being inserted into the character-shaped hole portion 16a (see FIG. 9), the winding shaft 16 is coaxially connected to the winding shaft 16 while being prevented from rotating. In this case, an engaging claw 23c is formed on the base end side of the main body portion 23a, and the engaging claw 23c is
The connecting shaft 23 is prevented from coming off by engaging with the engaging hole 16b (see FIG. 9) formed in the winding shaft 16 side in a state of communicating with the hole 16a.

A slit 23d (see FIG. 3) oriented in the axial direction is formed in a portion of the main body portion 23a adjacent to the shaft portion 23b, and the slit 23d has a slit 23d.
One hook portion 25a of a torsion coil spring 25 (corresponding to the spring means in the present invention) described later can be inserted. Further, a pin portion 23e, which constitutes a part of the rotation restricting means according to the present invention, is integrally formed at a position on the opposite side of the slit 23d in the main body portion 23a.

The tip of the shaft portion 23b of the connecting shaft 23 has a retaining piece 23 defined by a groove portion 23f extending in the circumferential direction.
g is provided, and the retaining piece 23g is chamfered to have a substantially D-shaped cross section.

The second pulley 22 includes a drum portion 26 for winding the wire 24 and a cylindrical portion 27 coaxial with the drum portion 26.
And the flange portion 26a, 26 for preventing the wire 24 from coming off on both sides of the drum portion 26.
b is formed. As shown in FIGS. 2 and 3, the shaft hole portion 28 formed in the cylindrical portion 27 has the second pulley 22.
Is provided so as to pass through in the axial direction, and the large diameter portion 28 into which the main body portion 23a of the connecting shaft 23 is rotatably inserted.
It has a shape including a and a small diameter portion 28b into which the shaft portion 23b of the connecting shaft 23 is rotatably inserted.

Further, the cylindrical portion 27 is formed with a notch portion 27a into which the pin portion 23e on the side of the connecting shaft 23 is inserted when the connecting shaft 23 is inserted into the shaft hole 28.
The pin portions 23e come into contact with the rising portions 27b and 27c on both sides of the cutout portion 27a, whereby the second pulley 22
The rotation range of is restricted within a predetermined angle. That is, the rising portions 27b and 27c together with the pin portion 23e constitute the rotation restricting means in the present invention.

The flange portion 26a of the shaft hole portion 28
A string-shaped wall portion 28c (see FIGS. 3, 4, and 5) is formed in the opening edge portion on the side so as to be flush with the flange portion 26a, whereby the shaft hole portion 28 (diameter Small part 28
b) Opening on the flange portion 26a side (shown by B in FIG. 4)
Has a substantially D shape slightly larger than the retaining piece 23g of the connecting shaft 23. The thickness dimension of the wall portion 28c (the dimension corresponding to the axial direction of the second pulley 22) is
It is set to a value slightly smaller than the width dimension of the groove 23f of the connecting shaft 23.

Also, the wall portion 2 of the second pulley 22.
A slit 22a (see FIGS. 4 and 5) oriented in the axial direction of the pulley 22 is formed at a position corresponding to 8c, and the hook portion 25b of the torsion coil spring 25 is inserted into the slit 22a. I'm supposed to get it. The slit 22a has a shape such that its bottom portion extends to a position flush with the inner peripheral surface of the large diameter portion 28a of the shaft hole portion 28.

Further, a stopper receiving portion 22 into which a spherical stopper 24a provided at the tip of the wire 24 is fitted in a portion of the second pulley 22 corresponding to the drum portion 26.
b is provided, and the wire guide slit 22c continuous with the stopper receiving portion 22b is provided in the drum portion 26.
And formed over the flange portions 26a and 26b.

In the following, a procedure for connecting the second pulley 22 and the connecting shaft 23 configured as described above will be described with reference to FIGS. 6 and 7. That is, first, the torsion coil spring 25 is mounted around the shaft portion 23b of the connecting shaft 23, and one hook portion 25a of the torsion coil spring 25 is positioned in the slit 23d of the connecting shaft 23. Next, the connecting shaft 23 with the torsion coil spring 25 attached in this manner is attached to the shaft hole 28 of the second pulley 22.
On the other hand, while being inserted from the cylindrical portion 27 side, at this time, the other hook portion 25b of the torsion coil spring 25 is inserted into the slit 22a on the second pulley 22 side.

At this time, the hooks 25a and 25b of the torsion coil spring 25 correspond to the slits 23d and 22a.
When it is inserted into the
The positional relationship in which g abuts against the back side of the wall portion 28c provided at the opening edge portion of the shaft hole portion 28 (that is, the opening portion B of the shaft hole portion 28 and the retaining piece formed in the substantially D shape, respectively). 23g and the positional relationship which do not match each other). Therefore, at the time of insertion, the second pulley 22 and the connecting shaft 23
6 is rotated relative to the torsion coil spring 25 to move the opening B and the retaining piece 23 as shown in FIG.
g, and in this state, put the retaining piece 23g into the opening B
6A, and then the relative rotation operation is released. (In the state of the positional relationship of FIG. 6A, the cutout portion 27a on the second pulley 22 side and the pin portion 23e of the connecting shaft 23 are not shown. 7 (a) has a positional relationship as shown in FIG.

Then, the spring force of the torsion coil spring 25 causes the second pulley 22 and the connecting shaft 23 to relatively return and rotate, so that the wall portion 28c fits into the groove portion 23f of the connecting shaft 23. As shown in FIG. 6B, the back side of the retaining piece 23g comes into contact with the wall portion 28c, so that the second pulley 22 is coupled to the coupling shaft 23 in the retaining state. (Note that in the state of the positional relationship of FIG. 6B, the cutout portion 27a and the pin portion 23e are different from those of FIG. 7B.
There is a positional relationship as shown in).

In this way, the second pulley 22 is connected to the connecting shaft 23.
It will be rotatably connected to the take-up shaft 16 via the rotary shaft. In this case, the rotatable range is the position where one rising portion 27b abuts on the pin portion 23e of the connecting shaft 23. And the other rising portion 27c is brought into contact with the pin portion 23e (the range indicated by the angle θ in FIG. 7).

Here, the spring force of the torsion coil spring 25 is the operating torque of the entire drive system in the state where the winding shafts 15 and 16, the film damper 19, the wire 24 and the like are incorporated (winding rotated by the motor 20). From the minimum operating torque of the shaft 15, the film damper 19 and the wire 24
It is set to a size capable of transmitting a torque equal to or greater than a value obtained by subtracting the operation torque of only the winding shaft 15 in the state where is not incorporated.

When the film damper 19 and the wire 24 are assembled, the second pulley 22 is rotated to the position shown in FIGS. 6 (c) and 7 (c).
At this time, the tension indicated by T1 acts on the wire 24, and this tension T1 balances with the spring force of the torsion coil spring 25. That is, the torsion coil spring 25
When the film damper 19 and the wire 24, etc. are assembled in a predetermined position, the second pulley 22 is connected to the wire 24.
The urging force is maintained in the rotatable range in the state of resisting the tension of the.

When an excessive tension T2 is applied to the wire 24 for some reason, the second pulley 22 is moved to the position shown in FIG.
(D), it comes to be rotated to the position shown in FIG. 7 (d), and at this time, the pin portion 23e and the rising portion 27c.
The spaces come into contact with each other, and further rotation is restricted.

Incidentally, FIG. 8 shows the second pulley 22 and the connecting shaft 23 in order to help understanding of the above-mentioned structure.
Relative angle (the state of FIG. 6A and FIG. 7A is zero),
The relationship with the torque acting on the torsion coil spring 25 is shown. In addition, "a, b, c, d" in FIG.
2 is (a), (b), (c), (d) in FIGS. 6 and 7.
Corresponds to the state at each position.

The motor 2 for driving the film damper 19
In the case of adopting a configuration in which 0 is feedforward-controlled, it is necessary to carry out the film damper 19 wound on the winding shaft 15 on the motor 20 side at the time of initial setting.

According to the configuration of this embodiment described above, the following actions and effects can be achieved. That is,
Each component such as the duct case 2 that supports the winding shafts 15 and 16, the film damper 19 that is wound between the winding shafts 15 and 16, and the wire 24 that is wound between the first pulley 21 and the second pulley 22. If there are variations in size or the sizes of the above-mentioned parts change with changes in the ambient temperature, these changes cause the size of the film damper 19 and the wire 24 itself to change, and the take-up shafts 15 and 16 respectively. This will appear as a change in the tension of the wire 24, since it will lead to a dimensional deviation between them. In this case, in the present embodiment, the second pulley 22 is provided so as to be rotatable within a predetermined angle θ with respect to the connecting shaft 23 connected to the winding shaft 16, and the pulley 22 acts on the wire 24. By providing a torsion coil spring 25 for urging the coil coil 25 so as to be positioned in the rotatable range against the tension applied to the connecting shaft 2,
Since the torque transmission between the third pulley 22 and the third pulley 22 is performed via the torsion coil spring 25, the change in tension is absorbed by the torsion coil spring 25.

Specifically, when the tension of the wire 24 is increased, the second pulley 22 is rotated in the direction of reducing the tension of the wire 24 against the spring force of the torsion coil spring 25. When the tension of the wire 24 is reduced, the second
The pulley 22 is rotated by the spring force of the torsion coil spring 25 so as to increase the tension of the wire 24.

As a result, it is possible to suppress an increase in the operation force required for moving the film damper 19, an increase in stress on each part, a slack in the film damper 19, and the like.
It is possible to prevent the situation in which the dimensional variations and dimensional changes of the respective components adversely affect the operation of the film damper 19 as described above. In this case, since the rotatable range of the second pulley 22 is restricted within the predetermined angle θ, the torque acting on the torsion coil spring 25 from the wire 24 is the torsion coil spring hand 25. Even when the allowable stress is exceeded, the risk of transmission of the rotational force between the take-up shaft 16 and the second pulley 22 is prevented.

Further, in the present embodiment, the function of retaining the second pulley 22 from the connecting shaft 23 is obtained by utilizing the spring force of the torsion coil spring 25. Has the advantage that there is no risk of complication.

In the above embodiment, the take-up shaft 16 on the driven side is
The second pulley 22 is rotatably connected within a predetermined angle range to the drive shaft of the take-up shaft 15 on the drive side.
It may be configured to be provided on the winding shaft 15 or the winding shafts 15 and 16. However, in the case where both the winding shafts 15 and 16 are provided with the above-described configuration, a configuration may be adopted in which the motor 20 for driving the film damper 19 is feedback-controlled according to the position of the film damper 19. desirable. Further, in the above embodiment, the torsion coil spring 25 is used as the spring means, but it is also possible to use a spring having another shape. Further, at least one of the winding shafts 10 and 11 corresponding to the air damper film damper 12 has the same structure as that of the above embodiment.

Besides, the present invention is not limited to the above-mentioned embodiments, and is not limited to, for example, an air conditioner for an automobile,
The present invention is widely applicable to general devices having a function of adjusting the opening degree of the air passage portion, and various modifications can be made without departing from the scope of the invention.

[0047]

As is clear from the above description, according to the air passage switching device of the first aspect, among the pair of pulleys connected to the pair of winding shafts for winding the film-shaped member. Since at least one of the winding shafts is rotatably connected to the corresponding winding shaft and spring means for transmitting torque between the winding shafts and the pulleys is provided, the wire wound between the pulleys is provided. It becomes possible to absorb the change in tension of the parts by the spring means, thereby preventing the situation in which the dimensional changes of the parts due to the dimensional variations of the parts and the ambient temperature change adversely affect the operation of the film-shaped member. It has an excellent effect that it can be done.

Further, according to the air passage switching device of the second aspect, the rotation restricting means for restricting the rotatable range of the pulley within a predetermined angle is provided, and the pulley means is provided with the thread member for the pulley. Since the structure is such that the tension is exerted on the spring means against the tension acting on the spring, the torque applied from the thread member to the spring means exceeds the allowable stress (torque transmission capacity) of the spring means. Even in this case, it is possible to obtain the effect that there is no possibility that the transmission of the rotational force between the winding shaft and the pulley is hindered.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of essential parts showing an embodiment of the present invention.

FIG. 2 is an exploded plan view showing a partial cross section of the same main part.

FIG. 3 is an exploded side view of the main part with a partial cross section.

FIG. 4 is a front view of the pulley.

[Figure 5] Rear view of the pulley

FIG. 6 is a front view showing a plurality of states with different main parts.

FIG. 7 is a rear view showing a plurality of different states of the same main part in a partial cross section.

FIG. 8 is a characteristic diagram for explaining a change state of torque acting on the spring means.

FIG. 9 is an exploded perspective view schematically showing a part of the main part omitted.

FIG. 10 is a cross-sectional view showing a schematic structure of an automobile air conditioner.

[Explanation of symbols]

In the drawings, 2 is a duct case, 8 is an air mix ventilation passage (air passage portion), 9 is a bypass ventilation passage (air passage portion),
Reference numerals 10 and 11 are winding shafts, 12 is a film damper (membrane member), 13 is a motor (driving unit), 15 and 16 are winding shafts, 19 is a film damper (membrane member), and 20 is a motor (driving unit). ), 21 is the first pulley, 22 is the second pulley,
Reference numeral 23 is a connecting shaft, 23e is a pin portion (rotation restricting means), 23
g is a retaining piece, 24 is a wire (thread member), 25 is a torsion coil spring (spring means), 26 is a drum portion, 27 is a cylindrical portion, 27a is a notch portion, and 27b and 27c are rising portions (rotation regulating means). ), 28 shows a shaft hole part.

Claims (2)

[Claims] 1. A film-like member for changing the opening of the air passage part in response to the movement of the air passage part while facing the air passage part, and a film-like member connected to both ends of the film-like member according to the rotation of itself. A pair of winding shafts for winding the film-shaped member, a pair of pulleys respectively connected to the respective winding shafts, and a thread-shaped member that is hung between these pulleys to rotate the respective winding shafts in an interlocking state, In an air passage switching device including a drive unit that rotationally drives at least one of the winding shafts to move the film-shaped member, at least one of the pair of pulleys is rotatable with respect to the corresponding winding shaft. And a spring means for applying a spring force to the rotatable pulley in a state where the film-shaped member, the winding shaft, the thread-shaped member, and the pulley are assembled at predetermined positions. Characterized by being provided The gas passage switching device. 2. A rotation restricting means for restricting a rotatable range of the pulley within a predetermined angle is provided, and the spring means has the film member, the winding shaft, the thread member and the pulley incorporated in predetermined positions. 2. The air passage switching device according to claim 1, wherein the pulley is arranged so as to urge the pulley so as to be located in the rotatable range against the tension acting on the thread member in the opened state.