JP3398990B2 - Air passage switching device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention
Air passage cut to change the opening of the air passage
Related to the replacement device, especially connected to both ends of the membrane member
To rotate the pair of winding shafts linked together
In addition, a pulley is connected to each take-up shaft
The air passage switching device that is configured to bridge the
You. [0002] 2. Description of the Related Art In recent years, air passages for automobile air conditioners have been cut off.
In the replacement device, the blower
Plastic switching damper and air mix damper.
Utilizing a film-like member made of a flexible material such as a backing film
Simple structure by configuring as a film damper
It is conceivable to reduce the overall weight and size, etc.
I have. In this type of air passage switching device, the air
To move the film damper in the forward and reverse directions,
While connecting both ends of the Lum damper to different winding shafts,
Each winding shaft is supported by a duct case.
Also, in order to rotate the winding shafts in conjunction with each other,
Pulleys are connected to each winding shaft, and between these pulleys
For example, a configuration in which a wire as a thread-like member is extended
And has been done. [0004] The conventional structure as described above
In the air passage switching device, the winding shaft and the pulley are integrated
It is connected to. For this reason, the film
Variations in dimensions of components such as dampers, wires, and duct cases
Each of the above components due to ambient temperature changes during actual use
The dimensional change of the
Increase the stress of each part or loosen the film damper
Adversely affect the operation of the film damper.
However, this point has been an unsolved problem. The present invention has been made in view of the above circumstances, and
Dimensions of each part due to dimensional variation of parts and changes in ambient temperature
The change is the change in the tension of the thread-like member spanned between the pulleys.
The purpose is to focus on the phenomenon that appears
Has a function to absorb the tension change of the thread-like memberSpring that demonstrates
meansDimensional variation of each part
Dimensional change of each part due to ambient temperature change activates the membrane member
Can be prevented from adversely affectingBoth
The torque acting on the spring means from the thread-like member
Even if the allowable stress by the means is exceeded, the winding shaft and
Eliminates the risk of interfering with the transmission of rotational force between the ribsAir vent
It is to provide a road switching device. [0006] The present invention achieves the above object.
To move in a position facing the air passage
Membrane member for changing the opening of the air passage according to the condition
And connected to both ends of this film-like member according to its own rotation.
A pair of winding shafts for winding the film-shaped member, and a pair of winding shafts.
A pair of pulleys connected to each other, and
Threaded part that rotates each winding shaft in an interlocked state
Material, and at least one of the winding shafts is driven to rotate,
Air passage comprising a driving means for moving the membrane member
In the switching device, at least one of the pair of pulleys
For pivotally connecting to the corresponding winding shaft
And the film-like member, the winding shaft, the thread-like member and the pulley.
The pivot is possible when the hook is installed in the predetermined position
Means for applying a spring force to a pulley in a stable stateWhen,
Rotation for restricting the rotatable range of the pulley within a predetermined angle
Regulating means, and the spring means, the film-shaped member,
A state in which the spindle, thread-like member and pulley are assembled
In this state, the pulley is resistant to tension acting on the thread-like member.
To be biased so as to be located in the rotatable range.
It is a thing. [0007] [0008] A film-like member whose both ends are wound around a pair of winding shafts,
Thread wound between a pair of pulleys connected to each winding shaft
Member, member provided to support each winding shaft, etc.
There is dimensional variation in each part of
When integrated, the dimensions of each part itself and each winding
Deviations in the dimensions between the spindles, or assembling integrally
The dimensions of each of the above parts are
If these changes occur with the
It appears as a change in the tension of the material and the thread. In this case,The present inventionIn the configuration of
Acts on a pulley connected in a rotatable state
Spring means is provided to allow the tension of the thread
At the time of increase, the pulley is thread-like against the spring force of the spring means.
It is now turned in the direction to reduce the tension of the material,
When the tension of the thread-like member is reduced, the pulley is
Rotation in the direction to increase the tension of the thread-like member by the spring force
Will be able to As described above, the tension of the thread member changes.
The pulley absorbs the tension change of the thread-like member according to
As a result, the operating force required to move the membrane member is reduced.
Increase or stress of each part, or loosening of the film-like member.
Is suppressed, and each component as described above is
Dimensional variations and dimensional changes have an adverse effect on the operation of film-like members.
Missing situations are prevented beforehand. [0011]AlsoThe pulley in the rotatable state is
The rotatable range is restricted within a predetermined angle by the rotation restricting means.
And the spring means connects the pulley with a thread.
Position in the pivotable range against the tension acting on the member
Is arranged so that the thread-like member
The torque acting on the spring means is allowed by the spring means.
Even if the stress (torque transmission capacity) is exceeded, the winding shaft and
There is no danger that transmission of torque between pulleys will be hindered.
It is. [0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention is applied to an automotive air conditioner.
An embodiment will be described with reference to the drawings. Car
In FIG. 10 showing a schematic cross-sectional structure of an air conditioner for
On the most downstream side of duct case 2 with blower 1
Is formed with a defroster outlet 3 and
Face outlet 4 and foot outlet 5 on both sides of outlet 3
Are formed. Each of the air outlets 3 to 5 is provided with an air passage according to the present invention.
The defroster outlet 3 is equivalent to a road.
It is provided to blow out conditioned air toward the door glass,
The face outlet 4 supplies air-conditioned air to the upper body of the occupant.
It is provided for blowing out, and the foot outlet 5 is at the foot of the occupant.
It is provided for blowing out conditioned air. In the duct case 2, a part close to the blower 1 is provided.
The evaporator 6 for air cooling is arranged at the
Downstream of the evaporator 6 and at the bottom of the duct case 2
The heater core 7 is arranged at the part side. In this case,
The data core 7 is provided in a form orthogonal to the evaporator 6.
As a result, a heater is provided in the duct case 2.
Air mix ventilation passages 8 and 7 separated by core 7
And bypass ventilation passages 9 (each corresponding to the air passage section of the present invention)
Is formed. The air mix ventilation passage 8 is provided for the heater core 7.
The air that passes through the heater core
7 is heated to flow into warm air. Also,
The bypass ventilation passage 9 is cooled by the evaporator 6
In order to allow air to flow through heater core 7 without flowing
Have been killed. The air mix in the duct case 2
A position facing the lower end of the air passage 8 and a bypass air passage.
The winding shafts 10 and 1 are respectively positioned at positions facing the upper end of the winding shaft 9.
1 is rotatably supported. For winding shafts 10 and 11
Is for an air mix corresponding to the film-like member referred to in the present invention.
Both ends of the film damper 12 are connected, and
The film damper 12 according to the forward and reverse rotation of the take-up shafts 10 and 11
Can be selectively moved in the forward and reverse directions.
One winding shaft 10 is a motor 1 having a built-in speed reduction mechanism.
Direct rotation by 3 (corresponding to the driving means in the present invention)
The other winding shaft 11 is driven by the motor 13.
Through a pulley (not shown) and a wire as a thread-like member.
And rotated. The film damper 12 is, for example, flexible.
The winding shaft 10,
The air-mix ventilation path is passed over 11 spaces
8 and the bypass ventilation path 9
In contact with the end face on the evaporator 6 side of the taco 7
It is provided in. Although not shown, the film damper 12
An opening is formed at a predetermined position, and this opening is
The air mixer is moved in accordance with the movement of the film damper 12.
One or both of the air passage 8 and the bypass air passage 9
By selectively opposing the air passages 8 and
9, the opening degree is changed.
And the amount of air blown through the air mix ventilation passage 8
The ratio to the amount of air blown through the pass ventilation path 9 can be adjusted as desired
It has become. In addition, winding in the duct case 2
A plate-shaped damper 1 for cooling air bypass is provided above the take-up shaft 11.
4 is provided, and this plate-shaped damper 14
Sometimes it is rotated to the position shown by the two-dot chain line
The cooling air from the heater 6 is supplied to the defroster outlet 3 and
It is configured to guide to the air outlet 4 side. On the other hand, the face in the duct case 2
The position of the outlet 4 facing the end of the blower 1 side,
Each position of the outlet 5 facing the heater core 7 side end
, Winding shafts 15 and 16 are rotatably supported.
Also, the defroster outlet 3 in the duct case 2
Intermediate position with face outlet 4 and defroster outlet
Each of the intermediate positions between the mouth 3 and the foot outlet 5 has a guide.
Roller shafts 17 and 18 are fixed between duct case 2
It is rotatably supported with a gap. Winding shaft
15 and 16 are blowers corresponding to the film-like member according to the present invention.
Both ends of the film damper 19 for mode switching are connected
In accordance with the forward and reverse rotation of the winding shafts 15, 16.
The lum damper 19 can be selectively moved in the forward and reverse directions.
It has become. The film damper 19 is, for example, flexible.
The winding shaft 15,
Between guide roller shafts 17, 18 and duct case 2 between 16
By passing through the gap of the
A star outlet 3, a face outlet 4, and a foot outlet 5
It is provided so as to be movable in an opposed state. The film damper 19 has a structure as shown in FIG.
In addition, a plurality of first
1 opening 19a, defroster outlet 3 and foot outlet
A plurality of second openings 19b selectively facing the mouth 5;
Has a predetermined dimension in the moving direction of the film damper 19.
It is formed in a separated state. This allows
The first opening 19a is closed in accordance with the movement of the lum damper 19.
Ace outlet 4 and a second opening
The part 19b is connected to the defroster outlet 3 and the foot outlet 5
By selectively opposing one or both
The degree of opening of the outlets 3 to 5 can be changed.
To obtain multiple types of ventilation modes according to various opening changes
It has become. FIG. 9 is related to the gist of the present invention.
In order to facilitate understanding of the parts, the main parts in FIG.
FIG. 3 is an exploded perspective view schematically showing the device in an omitted state.
Will be described with reference to FIG. That is, the take-up shaft 15 is decelerated at one end thereof.
Motor 20 with a built-in mechanism
The first pulley 21 is integrated with the other end at the other end.
Are connected via a shaft portion 21a. In addition, winding shaft 1
6, a second pulley 22 includes a connecting shaft 23, which is a separate component.
Between the pulleys 21 and 22
Is wound around a wire 24 as a thread-like member.
In this case, the first pulley 21 and the second pulley 22
The winding direction of the wire 24 is
Of the film damper 19 on the corresponding winding shafts 15 and 16
It is set to be opposite to the winding direction. Therefore, the winding shaft 15 and the
And when the first pulley 21 is rotated in the direction of arrow A in FIG.
In this case, the film damper 19 is wound around the winding shaft 15.
As the winding shaft 16 and the second pulley 22 also move in the direction of arrow A,
To the second pulley 22
Winds up the wire 24 sent from the first pulley 21
Become so. On the contrary, the winding shaft 1 is
5 and the first pulley 21 are rotated in the direction opposite to the arrow A
In such a case, the wire 24 is wound around the first pulley 21
, The second pulley 22 and the take-up shaft 16 are
The winding shaft 16 is rotated in the opposite direction.
The lum damper 19 is wound up. As a result,
By rotating the motor 20 forward and backward, the film
That can reciprocate the damper 19 in the forward and reverse directions
It is. In the following, the second pulley 22 and
Refer to FIGS. 1 to 5 for the configuration of the related parts.
I will explain while. That is, the connecting shaft 23 has a circular cross section.
The main body portion 23a and the shaft portion 23b having a smaller diameter than this are integrally provided.
It has a shaped shape. This connecting shaft 23 is
The base portion of 23a has a substantially D-shaped cross section.
This portion is formed in the cross section substantially D
To be inserted into the V-shaped hole 16a (see FIG. 9).
Coaxial with the winding shaft 16 in a stopped state.
It is connected in a shape. In this case, on the base end side of the main body portion 23a
An engagement claw 23c is formed, and this engagement claw 23c is
It is formed on the winding shaft 16 side in communication with the hole 16a.
By engaging with the engaging hole 16b (see FIG. 9).
Thus, the connection shaft 23 is prevented from coming off. The shaft 23b of the main body 23a
A slit 23d oriented in the axial direction (FIG.
3) is formed, and in this slit 23d,
A torsion coil spring 25 described later (spring means in the present invention)
So that one of the hook portions 25a can enter.
Has become. Further, the slip in the main body 23a is
The rotation restricting hand according to the present invention is located at a position opposite to
A pin portion 23e constituting a part of the step is integrally formed to protrude.
ing. At the tip of the shaft portion 23b of the connecting shaft 23,
Piece 23 defined by a groove 23f extending in the direction
g is provided, and this retaining piece 23g is chamfered.
To form a substantially D-shaped cross section.
You. The second pulley 22 is provided with a wire for winding the wire 24.
A ram portion 26 and a cylindrical portion 27 coaxial with the drum portion 26
And the drum unit 26
The flanges 26a, 26 for preventing the wire 24 from coming off
b is formed. Shaft formed in the cylindrical portion 27
The hole 28 is provided in the second pulley 22 as shown in FIGS.
Are provided so as to penetrate in the axial direction, and the connecting shaft
Large-diameter portion 28 into which the main body portion 23a of 23 is rotatably inserted.
a and the shaft portion 23b of the connection shaft 23 is rotatably inserted.
And a small diameter portion 28b. The cylindrical portion 27 is connected to a shaft hole 28.
With the shaft 23 inserted, the pin on the connection shaft 23 side
Notch portion 27a into which the connecting portion 23e enters is formed,
In the rising portions 27b and 27c on both sides of the notch 27a
When the pin portion 23e contacts the second pulley 22
The rotation range is restricted within a predetermined angle.
You. That is, the rising portions 27b and 27c are
Together with the portion 23e, it constitutes the rotation restricting means of the present invention.
It is. The flange 26a in the shaft hole 28
The opening edge on the side has a lunar wall 28c (FIG. 3, FIG.
4, see FIG. 5) is flush with the flange 26a.
The shaft hole 28 (small diameter portion 28)
b) Opening on the flange portion 26a side (indicated by B in FIG. 4)
Is slightly larger than the retaining piece 23g of the connection shaft 23.
It becomes D-shaped. The thickness of the wall 28c
The dimension (dimension corresponding to the axial direction of the second pulley 22) is
Slightly smaller than the width of the groove 23f of the connecting shaft 23
Is set to a value. The wall portion 2 of the second pulley 22
8c, a finger is provided in the axial direction of the pulley 22.
Facing slits 22a (see FIGS. 4 and 5)
The slit 22a has the torsion coil spring
25 hooks 25b can enter
You. The bottom of the slit 22a has the diameter of the shaft hole 28.
The shape extends to a position flush with the inner peripheral surface of the large portion 28a.
ing. Further, the drum portion of the second pulley 22
26, a portion provided at the tip of the wire 24 is provided.
Stopper receiving portion 22 into which the formed spherical stopper 24a fits
b and the stopper receiving portion 22b
The continuous wire guide slit 22c is
And formed over the flange portions 26a and 26b
I have. In the following, the structure as described above is used.
Diagram of connection procedure between second pulley 22 and connection shaft 23
6 and FIG. That is, first, the connecting shaft
A torsion coil spring 25 is mounted around the shaft portion 23b of 23.
And one hook of the torsion coil spring 25
Position the part 25a in the slit 23d of the connecting shaft 23
You. Next, the torsion coil spring 25 is attached in this manner.
The connection shaft 23 in the separated state is inserted into the shaft hole 28 of the second pulley 22.
To the cylindrical part 27 side, and at this time
And the other hook portion 25b of the torsion coil spring 25 is
2 Insert it into the slit 22a on the pulley 22 side. At this time, the both ends of the torsion coil spring 25 are
Slits 23d and 22a corresponding to the lock portions 25a and 25b
In the state where the stopper piece 23 at the tip of the connecting shaft 23 is inserted.
g is the back of the wall 28 c provided at the opening edge of the shaft hole 28.
Positions that abut the sides (that is, approximately D-shaped
The opening B of the shaft hole 28 and the retaining piece 23g
Are not set to match each other). this
Therefore, at the time of the insertion, the second pulley 22 and the connecting shaft 23
Is rotated relatively against the torsion coil spring 25.
Then, as shown in FIG.
g, and in this state, the retaining piece 23g is
And then release the relative rotation operation.
(Note that, in the state of the positional relationship of FIG.
The notch 27a on the side of the rib 22 and the pin 23e of the connecting shaft 23
Are in a positional relationship as shown in FIG. Then, the spring force of the torsion coil spring 25 is
As a result, the second pulley 22 and the connection shaft 23 relatively return and rotate.
Then, the wall portion 28c is fitted into the groove portion 23f of the connecting shaft 23.
As shown in FIG. 6 (b),
The back side of the piece 23g comes into contact with the wall 28c.
To the connecting shaft 23 in a state where the second pulley 22 is
(Note that the positional relationship shown in FIG.
In the state, the notch 27a and the pin 23e are connected to each other as shown in FIG.
In the positional relationship as shown in the figure). As described above, the second pulley 22 is connected to the connecting shaft 23
Rotatably connected to the winding shaft 16 via the
In this case, the rotatable range is one
The barb 27b is brought into contact with the pin 23e of the connecting shaft 23.
Position and the other rising portion 27c against the pin portion 23e.
Regulated between the contacted position (range indicated by angle θ in FIG. 7)
Will be done. Here, the spring of the torsion coil spring 25 is used.
The force is applied to the winding shafts 15 and 16, the film damper 19 and the
Operation of the entire drive system with the gears 24 etc. incorporated
Torque (minimum of winding shaft 15 rotated by motor 20)
From the operating torque), the film damper 19 and the wire 24
Operating torque of only the take-up shaft 15 without the
Set to a size that can transmit torque equal to or greater than the value
It is what is done. Assembling the film damper 19 and the wire 24
When the second pulley 22 is set in the state shown in FIG.
It is rotated to a position as shown in FIG.
At this time, the tension indicated by T1 acts on the wire 24.
And the tension T1 is the spring force of the torsion coil spring 25.
Will come to balance. That is, the torsion coil spring 25
Means that the film damper 19 and the wire 24 are at predetermined positions.
When the second pulley 22 is mounted on the wire 24,
In the rotatable range while resisting the tension of
Will be. Also, if the wire 24 is excessively large for some reason,
When the tension T2 acts, the second pulley 22
(D), so as to rotate to the position shown in FIG.
At this time, the pin portion 23e and the rising portion 27c
As the gap comes into contact, further rotation is restricted.
Become so. FIG. 8 shows the structure of the above configuration.
To help the solution, the second pulley 22 and the connecting shaft 23
(The states of FIGS. 6A and 7A are zero),
The relationship with the torque acting on the torsion coil spring 25 is shown.
Was. Note that “a, b, c, d” in FIG.
2 is (a), (b), (c), (d) in FIGS.
Corresponds to the state at each position. The motor 2 for driving the film damper 19
In the case of adopting the configuration to feed-forward control 0
In the initial setting, the film damper 19 is
It is necessary to carry out the process with the winding shaft 15 wound on the
is there. According to the configuration of the present embodiment described above,
The functions and effects described above can be obtained. That is,
Duct case 2 supporting winding shafts 15 and 16, winding shaft
The film damper 19 spanned between 15 and 16
The wire spanned between the first pulley 21 and the second pulley 22
Dimensional variation in each part such as
The dimensions of each of the above components may change with changes in ambient temperature.
In such a case, those changes are caused by the film damper 19 and the
Of the dimensions of the yarn 24 itself and the distance between the winding shafts 15 and 16
This will cause the dimensions to be out of order.
24 will appear as a change in tension. In this case, the book
In the embodiment, the second pulley 22 is connected to the winding shaft 16.
In a state where it can rotate within a predetermined angle θ with respect to the
And act on the pulley 22 on the wire 24
Energizes against the tension so that it is located in the above-mentioned rotatable range
By providing the torsion coil spring 25, the connecting shaft 2
The torque transmission between the third pulley 22 and the second pulley 22
The configuration is performed through the spring 25
The change in tension is absorbed by the torsion coil spring 25
Become like Specifically, when the tension of the wire 24 is increased,
Means that the second pulley 22 is driven by the spring force of the torsion coil spring 25
The wire 24 is turned in a direction to decrease the tension of the wire 24
And when the tension of the wire 24 decreases, the second
The pulley 22 is displaced by the spring force of the torsion coil spring 25.
The ear 24 is rotated in a direction to increase the tension.
You. This allows the film damper 19 to move.
The required operating force increases, the stress of each part increases,
The slack of the film damper 19 is suppressed,
The dimensional variation and dimensional change of each part
Prevents adverse effects on the operation of the damper 19
Is done. In this case, the second pulley 22 can rotate.
Whether the range is restricted within the predetermined angle θ
From the wire 24 acting on the torsion coil spring 25
If Luk is the torsion coilNe2Exceeding the allowable stress by 5
Even in this case, the rotational force between the winding shaft 16 and the second pulley 22
There is no fear that transmission will be hindered. In this embodiment, the connection of the second pulley 22
The function of preventing the connection from the connecting shaft 23 is
Because we use spring force to obtain,
This has the advantage that the configuration for
You. In the above embodiment, the take-up shaft 16 on the driven side is used.
The second pulley 22 is rotatably connected within a predetermined angle range.
However, such a configuration is adopted for the winding shaft 15 on the driving side.
Or provided on both winding shafts 15 and 16
It is good also as a structure which is. However, the winding shaft 15 and
In the case where the above configuration is provided in both
The motor 20 for driving the lum damper 19 is
Feedback control according to the position of the damper 19
It is desirable to adopt it. In the above embodiment, the spring
A configuration using a torsion coil spring 25 as a means is adopted.
However, other shapes of springs can be utilized. Further
And a winding corresponding to the film damper 12 for air mixing.
At least one of the spindles 10 and 11 is the same as in the above embodiment.
And the like. In addition, the present invention is limited to the above-described embodiment.
Not limited to, for example, automotive air conditioners,
In general, devices with the function of adjusting the opening of the air passage
Various applications that do not deviate from the gist, such as being widely applicable
It can be modified and implemented. [0047] As is apparent from the above description,Book
According to the inventionAccording to the air passage switching device, the membrane member is wound.
A pair of pulleys connected to a pair of take-up shafts
That is, at least one can be rotated with respect to the corresponding winding shaft.
In a state, and the
Since spring means for transmitting torque is provided,
The change in the tension of the wire stretched between
Therefore, it becomes possible to absorb,
Dimensional change of each part due to dimensional variation and ambient temperature change
A situation that adversely affects the operation of the membrane member can be prevented beforehand.
This is an excellent effect that Also,According to the inventionBy air passage switching device
If so, the rotatable range of the pulley is restricted within a predetermined angle.
Rotation restricting means, and the spring means
The pulley is rotated against the tension acting on the thread member.
Because it is configured to be urged to be located in the possible range, the thread
The torque acting on the spring means from the member is applied to the spring means.
Even if the allowable stress (torque transmission capacity) exceeds
There is no danger that the transmission of rotational force between the take-up shaft and pulley will be hindered.
The effect that becomes becomes.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a main part showing an embodiment of the present invention. FIG. 2 is an exploded plan view of the main part in a partially sectioned state. FIG. 4 is a front view of the pulley. FIG. 5 is a rear view of the pulley. FIG. 6 is a front view showing a plurality of different states of the main part. FIG. FIG. 8 is a rear view showing a partial cross section of a plurality of states having different parts. FIG. 8 is a characteristic diagram for explaining a torque change state acting on a spring means. FIG. FIG. 10 is a cross-sectional view showing a schematic structure of an automotive air conditioner. DESCRIPTION OF REFERENCE NUMERALS In the drawings, 2 is a duct case, 8 is an air mix ventilation passage (air passage portion), and 9 is a bypass ventilation passage. (Air passage),
10 and 11 are winding shafts, 12 is a film damper (membrane member), 13 is a motor (driving means), 15 and 16 are winding shafts, 19 is a film damper (membrane member), and 20 is a motor (driving means). ), 21 is a first pulley, 22 is a second pulley,
23 is a connecting shaft, 23e is a pin (rotation restricting means), 23
g is a retaining piece, 24 is a wire (thread-like member), 25 is a torsion coil spring (spring means), 26 is a drum part, 27 is a cylindrical part, 27a is a notch, 27b and 27c are rising parts (rotation restricting means). ) And 28 indicate shaft holes.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60H 1/00 102 F24F 13/10

Claims (1)

(1) A film-like member for changing an opening degree of an air passage according to movement in a state facing an air passage, and both ends of the film-like member And a pair of winding shafts that wind the film-shaped member according to its own rotation, and a pair of pulleys that are respectively connected to the winding shafts. An air passage switching device comprising: a thread-shaped member that rotates in a state where the film is rotated; and a driving unit that rotationally drives at least one of the winding shafts to move the film-shaped member. After being configured to be rotatably connected to the take-up shaft, the film-like member, the take-up shaft, the thread-like member, and the pulley are rotatably mounted in a predetermined position. spring means for applying a spring force against Rotation to restrict the rotation range of the pulley to a predetermined angle within the
Regulating means, wherein the spring means comprises the film-like member, the winding shaft, the thread-like member and
When the pulley is installed at the specified position,
The pivotable range against the tension acting on the thread member
An air passage switching device, wherein the air passage switching device is arranged so as to be biased so as to be located at a position .