U.S. patent application number 09/906191 was filed with the patent office on 2002-01-24 for inside/outside air switching device with rotary door.
Invention is credited to Sato, Yasuhiro.
Application Number | 20020009969 09/906191 |
Document ID | / |
Family ID | 18713867 |
Filed Date | 2002-01-24 |
United States Patent
Application |
20020009969 |
Kind Code |
A1 |
Sato, Yasuhiro |
January 24, 2002 |
Inside/outside air switching device with rotary door
Abstract
In an inside/outside air switching device, a seal member is
provided at a position around a rotation center axial line of a
rotary door, for sealing an inside/outside air switching box in an
axial direction. The rotary door is disposed to be elastically
deformable in such a manner that at least both parts of side wall
plates of the rotary door around the rotation center axial line are
displaced away from each other by a dynamical pressure of a vehicle
travelling, applied to an outer wall plate of the rotary door, in
an inside air mode. The seal member press-contacts the
inside/outside air switching box when at least both the parts of
the side wall plates around the rotation center axial line are
displaced away from each other.
Inventors: |
Sato, Yasuhiro;
(Okazaki-city, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, PLC
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
18713867 |
Appl. No.: |
09/906191 |
Filed: |
July 16, 2001 |
Current U.S.
Class: |
454/139 |
Current CPC
Class: |
Y10T 137/86847 20150401;
B60H 1/00671 20130101; Y10T 137/86815 20150401 |
Class at
Publication: |
454/139 |
International
Class: |
B60H 001/26 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 19, 2000 |
JP |
2000-219010 |
Claims
What is claimed is:
1. An inside/outside air switching device for a vehicle,
comprising: an inside/outside air switching box having an inside
air suction port from which inside air inside a passenger
compartment of the vehicle is introduced, and an outside air
suction port from which outside air outside the passenger
compartment is introduced; a rotary door for selectively opening
and closing the inside air suction port and the outside air suction
port, the rotary door being disposed in the inside/outside air
switching box to be rotatable around a rotation center axial line;
and a seal member provided at a position around the rotation center
axial line, for sealing the inside/outside air switching box in an
axial direction, wherein: the rotary door includes an outer wall
plate extending in a rotation direction of the rotary door, and
both side wall plates extending from both end portions of the outer
wall plate in an axial direction toward the rotation center axial
line, respectively; the rotary door is disposed to be elastically
deformable in such a manner that at least both parts of the side
wall plates around the rotation center axial line are displaced
away from each other by a dynamical pressure of a vehicle
travelling, applied to the outer wall plate, in an inside air mode
where the rotary door closes the outside air suction port and opens
the inside air suction port; and the seal member press-contacts an
inner surface of the inside/outside air switching box when at least
both the parts of the side wall plates around the rotation center
axial line are displaced away from each other by a predetermined
distance.
2. The inside/outside air switching device according to claim 1,
wherein the seal member is provided on the side wall plates around
the rotation center axial line.
3. The inside/outside air switching device according to claim 1,
wherein the seal member is disposed at both positions outside the
rotary door to be separated from the parts of the side wall plates
around the rotation center axial line, respectively, in the axial
direction.
4. The inside/outside air switching device according to claim 1,
wherein, in a natural state of the rotary door, both the side wall
plates are tilted, respectively, toward the sides of the
displacements, relative to a direction perpendicular to the outer
wall plate.
5. The inside/outside air switching device according to claim 4,
wherein each of the side wall plates is tilted by a tilt angle
equal to or larger than 10 degrees.
6. The inside/outside air switching device according to claim 1,
wherein the outer wall plate is formed into a shape to have a
rigidity in a direction perpendicular to the rotation center axial
line, larger than a predetermined value.
7. The inside/outside air switching device according to claim 1,
wherein the outer wall plate has a wave shape extending in the
rotation direction of the rotary door.
8. The inside/outside air switching device according to claim 1,
wherein: the seal member has a contact surface opposite to the
inner surface of the inside/outside air switching box; and and the
contact surface is parallel to the inner surface of the
inside/outside air switching box.
9. The inside/outside air switching device according to claim 8,
further comprising an elastic member on the contact surface of the
seal member.
10. The inside/outside air switching device according to claim 1,
wherein: the rotary door has both rotation shafts connected to both
the side wall plates, respectively, around the rotation center
axial line; and the rotation shafts are displaced away from each
other by the dynamical pressure of the vehicle travelling, applied
to the outer wall plate, in the inside air mode.
11. The inside/outside air switching device according to claim 10,
wherein: the inside/outside air switching box has both bearing
holes in which the rotation shafts are held, respectively, to be
rotatable; and the seal member press-contacts the inner surface of
the inside/outside air switching box around the bearing holes.
12. The inside/outside air switching device according to claim 11,
wherein the seal member is disposed on the rotation shafts at
outside of each side wall plate, to be parallel to the inner
surface.
13. The inside/outside air switching device according to claim 11,
wherein the seal member is disposed in each side wall plate around
the rotational center axial line to be parallel to the inner
surface.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is related to Japanese Patent Application
No. 2000-219010 filed on Jul. 19, 2000, the contents of which are
hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an inside/outside air
switching device using a rotary door as an inside/outside air
switching door. More particularly, the present invention relates to
a seal structure of the inside/outside air switching door in an
inside air mode.
[0004] 2. Description of Related Art
[0005] A conventional rotary-type inside/outside air switching door
is formed into a gate shape having a rotation shaft inserted into
both bearing holes, an outer wall plate extending in a rotation
direction around the rotation shaft, and both side wall plates
connecting the outer wall plate and both axial ends of the rotation
shaft. Further, a packing member is provided in periphery portions
of the side wall plate and the outer wall plate, and a seal surface
is provided on an inside/outside air switching box to have a shape
corresponding to the packing member. In the inside/outside air
switching device, for obtaining a seal function between the
inside/outside air switching door and the inside/outside air
switching box, the packing member is pressed to the seal surface in
the rotation direction of the rotation shaft. On the other hand, in
the axial direction of the rotation shaft, a clearance is provided
between a part of the side wall plates around the rotation shaft
and an inner surface of the inside/outside air switching box, for
rotating the inside/outside air switching door.
[0006] However, in an inside air mode where the inside/outside air
switching door closes an outside air suction port of the
inside/outside air switching box and closes an outside air suction
port of the inside/outside air switching box, air pressure at a
side of the outside air suction port of the rotary door becomes
higher due to dynamical pressure (ram pressure) in a vehicle
travelling. Accordingly, in this seal structure of the
inside/outside air switching door, because the clearance is
provided between the part of the side wall plate around the
rotation shaft and the inner surface of the inside/outside air
switching box, outside air may be leaked due to the dynamical
pressure in the vehicle traveling. Thus, in the inside air mode,
outside air may be mixed into inside air within the inside/outside
air switching box.
SUMMARY OF THE INVENTION
[0007] In view of the foregoing problems, it is an object of the
present invention to provide an inside/outside air switching device
with a rotary door, which prevents a leakage of outside air from
the inside/outside air switching door into an inside/outside air
switching box in an inside air mode.
[0008] According to the present invention, in an inside/outside air
switching device, a rotary door for selectively opening and closing
an inside air suction port and an outside air suction port is
disposed in an inside/outside air switching box to be rotatable
around a rotation center axial line, and a seal member for sealing
the inside/outside air switching box in an axial direction is
provided at a position around the rotation center axial line. The
rotary door includes an outer wall plate extending in the rotation
direction of the rotary door, and both side wall plates extending
from both end portions of the outer wall plate in an axial
direction toward the rotation center axial line, respectively. The
rotary door is disposed to be elastically deformable in such a
manner that at least both parts of the side wall plates around the
rotation center axial line are displaced away from each other by a
dynamical pressure of a vehicle travelling, applied to the outer
wall plate, in an inside air mode where the rotary door closes the
outside air suction port and opens the inside air suction port.
Further, the seal member press-contacts the inside/outside air
switching box when at least both the parts of the side wall plates
around the rotation center axial line are displaced away from each
other by a predetermined distance. Thus, when the rotary door
closes the outside air suction port and opens the inside air
suction port in the inside air mode, the seal member press-contacts
the inner surface of the inside/outside air switching box to seal a
clearance between the inside/outside air switching box and the
rotary door in the axial direction. Accordingly, in the inside air
mode, it can prevent a leakage of outside air from the
inside/outside air switching door (rotary door) into the
inside/outside air switching box.
[0009] On the other hand, when the vehicle is travelling in low
speed lower than a predetermined speed, the dynamical pressure in
the vehicle travelling becomes lower. In this case, the
displacement of the side wall plates due to the elastic deformation
of the rotary door becomes smaller, and the seal member does not
contact the inner surface of the inside/outside air switching box.
However, because the dynamical pressure applied to the outer wall
plate of the rotary door is small, a leakage of outside air into
the inside/outside air switching box in the inside air mode can be
substantially prevented. In this case, a sliding pressure of the
rotary door can be reduced.
[0010] Preferably, in a natural state of the rotary door, both the
side wall plates are tilted, respectively, toward the sides of the
displacements, relative to a direction perpendicular to the outer
wall plate. Therefore, a rotation moment generated to the side wall
plates in the rotation direction of the rotary door can be
increased, and the side wall plates can be readily displaced away
from each other. More preferably, the tilt angle of each side wall
plate is equal to or larger than 10 degrees.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Additional objects and advantages of the present invention
will be more readily apparent from the following detailed
description of preferred embodiments when taken together with the
accompanying drawings, in which:
[0012] FIG. 1 is a schematic sectional view showing a blower unit
including an inside/outside air switching device, for a vehicle air
conditioner, according to a first preferred embodiment of the
present invention;
[0013] FIG. 2 is a perspective view showing an inside/outside air
switching door according to the first embodiment;
[0014] FIGS. 3A and 3B are cross-sectional views taken along line
III-III in FIG. 1, FIG. 3A showing a natural state of the
inside/outside air switching door without an elastic deformation
and FIG. 3B showing an elastic deformation state of the
inside/outside air switching door, according to the first
embodiment;
[0015] FIG. 4 is a cross-sectional view taken along line IV-IV in
FIG. 3A; and
[0016] FIG. 5A is a cross-sectional view showing a natural state of
an inside/outside air switching door without an elastic
deformation, and FIG. 5B is a cross-sectional view showing an
elastic deformation state of the inside/outside air switching door,
according to a second preferred embodiment of the present
invention.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
[0017] A first preferred embodiment of the present invention will
be described hereinafter with reference to FIGS. 1-4. FIG. 1 shows
a blower unit including an inside/outside air switching device and
a blower, disposed in a ventilation system of a vehicle air
conditioner, in an inside air mode.
[0018] Generally, the blower unit is disposed under an instrument
panel at a front side in a passenger compartment of a vehicle on a
front-passenger's side. An inside/outside air switching box (case)
10 made of a plastic resin defines an air passage of the
inside/outside air switching device. A scroll casing 20 is disposed
under the inside/outside air switching box 10 adjacent to the
inside/outside air switching box 10, so that an inner side of the
inside/outside air switching box 10 communicates with a bell-mouth
like suction port 21 of the scroll casing 20.
[0019] An air filter 22 for filtering dust contained in air and for
removing a smelling component in air is disposed in the scroll
casing 20 at an upstream air side of the bell-mouth like suction
port 21. The air filter 22 is constructed by a filter material, and
a resinous frame. In the filter material of the air filter 22, an
absorption material such as an activated carbon for absorbing
smelling components may be added in accordance with a necessity.
However, the present invention may be applied to an air conditioner
without providing the air filter 22.
[0020] A blower fan 24 composed of a centrifugal multi-blade fan
(sirocco) is disposed in the scroll casing 20 at a downstream air
side of the air filter 22. That is, the fan 24 is disposed in the
scroll casing 20 so that air sucked from a suction port 21 flows
toward a radial outside of the fan 22 by the rotation of the fan
22. The fan 24 is connected to a rotation shaft 26 of a driving
motor 25 to be rotated.
[0021] The inside/outside air switching box 10 has an inside air
suction port 11 from which inside air inside the passenger
compartment is introduced, and an outside air suction port 12 from
which outside air outside the passenger compartment is introduced.
In a vehicle front-rear direction, the inside air suction port 11
is provided at a vehicle rear side of the outside air suction port
12.
[0022] Within the inside/outside air switching box 10, a
rotary-type inside/outside air switching door 30 (i.e., rotary
door) is rotatably disposed to open and close the inside air
suction port 11 and the outside air suction port 12. As shown in
FIGS. 2 and 3, both bearing holes 13 are provided in the
inside/outside air switching box 10 to have the same axial center
line .phi., and the rotary-type inside/outside air switching door
30 is disposed to be rotated around the same axial center line
.phi. of the bearing holes 13.
[0023] FIG. 2 is a perspective view showing the rotary-type
inside/outside air switching door 30. The inside/outside air
switching door 30 has both rotation shafts 30a inserted into the
bearing holes 13, an outer wall plate 30b extending in a door
rotation direction, and both side wall plates 30c connecting both
end portions of the outer wall plate 30 in an axial direction and
the rotation shaft 30a. That is, as shown in FIG. 3A, the
inside/outside air switching door 30 is formed into a gate-like
sectional shape. The rotation shafts 30a protrude outside in the
axial direction, and are held rotatably in the bearing holes 13,
respectively. One end of the rotation shaft 30a is connected to a
door operation mechanism (not shown) at an outside of the
inside/outside air switching box 10 to be rotated.
[0024] The dimension of the outer wall plate 30b is set at a
necessary dimension to close the outside air suction port 12, while
the dimensions of the outer wall plate 30b and the side wall plates
30c are set at necessary dimensions to close the inside air suction
port 11. As shown in FIG. 3A, in a natural state without an elastic
deformation of the inside/outside air switching door 30, both the
side wall plates 30c are tilted respectively toward arrows "c"
relative to a direction (up-down direction in FIG. 3A)
perpendicular to the outer wall plate 30b. In the first embodiment,
each tilt angle .theta. of the side wall plate 30c is approximately
10 degrees. Further, as shown in FIG. 4, the outer wall plate 30b
is formed into a wave shape (i.e., uneven shape) extending in the
door rotation direction.
[0025] Further, as shown in FIG. 2, a rib (protrusion) 30d
extending to a door outside is formed in peripheral portions of the
side wall plates 30c and the outer wall plate 30b, and packing
members 31, 32 are bonded on both face and back surfaces of the rib
30d using an adhesive. Each of the packing members 31, 32 is made
of a porous foam such as urethane foam, and is formed into a plate
like.
[0026] On the other hand, as shown in FIG. 4, seal surfaces 14, 15
protruding toward the inside/outside air switching door 30 are
integrally provided with the inside/outside air switching box 10 on
peripheral portions of the inside air suction port 11 and the
outside air suction port 12. The packing members 31, 32 are
attached to the inside/outside air switching door 30 so that
surfaces of the packing members 31, 32 press-contact the seal
surfaces 14, 15 of the inside/outside air switching box 10 in the
door rotation direction. Accordingly, the inside air suction port
11 or the outside air suction port 12 can be air-tightly sealed by
the inside/outside air switching door 30.
[0027] Further, as shown in FIGS. 1-4, seal members 30e each
protruding in a fan like on a peripheral surface of the rotation
shaft 30a are provided at sides of the side wall plates 30c to be
positioned between both parts of the rib 30d. The seal members 30e
are provided for sealing the inside/outside air switching box 10 in
the axial direction. On the other hand, the other side peripheral
surface of each rotation shaft 30a, opposite to the seal member
30e, is formed to be positioned on the same surface as an end
surface of the rib 30d, as shown in FIG. 2.
[0028] The rotation shafts 30a, the outer wall plate 30b, the side
wall plates 30c, the rib 30d and the seal members 30e of the
inside/outside air switching door 30 are integrally formed by resin
such as polypropylene. In the first embodiment, the inside/outside
air switching door 30 is formed to be elastically deformable. FIG.
3A shows a position relationship between the inside/outside air
switching door 30 and the inside/outside air switching box 10 in a
natural state without an elastic deformation, and FIG. 3B shows a
position relationship between the inside/outside air switching door
30 and the inside/outside air switching box 10 in an elastic
deformation state.
[0029] In an inside air mode, dynamical pressure (ram pressure) of
a vehicle traveling, is applied to the outer wall plate 30b of the
inside/outside air switching door 30 as shown in FIG. 3A, so that
the rotation shafts 30a and the portions of the side wall plates
30c around the rotation shafts 30a are elastically deformed in the
arrows "c". That is, the outer wall plate 30b is pressed toward the
side wall plates 30c by the ram pressure, and the side wall plates
30c are pressed toward the rotation shafts 30a. Accordingly, the
rotation shafts 30a slide in the bearing holes 13 toward outside in
the axial direction, and are displaced toward outside of the
inside/outside air switching box, respectively. With this
displacement of the rotation shafts 30a, the seal members 30e
contact peripheral wall surfaces of the bearing holes 13 on the
inner surface of the inside/outside air switching box 10.
[0030] In the first embodiment, the inside/outside air switching
door 30 is set, so that the seal members 30e press-contact the
inner surface of the inside/outside air switching box 10 in the
axial direction when the ram pressure is equal to or larger than
200 Pa.
[0031] Because the inside air suction port 11 is opened and closed
not only the outer wall plate 30b but also the side wall plates 30c
of the inside/outside air switching door 30, the inside air suction
port 11 includes a circumference opening 11a positioned on a
vehicle rear side of the inside/outside air switching box 10, and
both side openings 11b of the inside/outside air switching box 10
in a vehicle left-right direction. Accordingly, the shape of the
inside air suction port 11 is formed into a gate shape opened from
a position opposite to the outer wall plate 30b to positions
opposite to both the side wall plates 30c. Thus, an opening area
for sucking inside air is increased, and maximum cooling capacity
in the inside air mode can be improved. On the other hand, the
outside air suction port 12 is formed into a rectangular flat
opening shape. Further, the inside/outside air switching door 30 is
a rotary door constructed to open and close the circumference
opening 11a and the side openings 11b.
[0032] Further, as shown in FIGS. 3A and 3B, an inner space defined
by the outer wall plate 30b and the side wall plates 30c of the
inside/outside air switching door 30 is directly opened to an
outside in a paper face-back direction of FIGS. 3A and 3B.
Therefore, as shown by arrow "a" in FIGS. 1, 4, air freely flows
through the inner space of the inside/outside air switching box
10.
[0033] Next, operation of the inside/outside air switching device
according to the first embodiment will be now described. By
rotating the rotary-type inside/outside air switching door 30
around the rotation shafts 30a, the inside air mode or an outside
air mode can be switched. FIG. 1 shows a state of the inside air
mode.
[0034] In the inside air mode, the packing members 31, 32 of the
inside/outside air switching door 30 press-contact the seal
surfaces 14, 15 around the outside air suction port 12, so that the
outside air suction port 12 is fully closed and the inside air
suction port 11 is fully opened. Accordingly, by the operation of
the blower fan 24, inside air is sucked from the inside air suction
port 11, and is blown toward an air conditioning unit of the
vehicle air conditioner.
[0035] Next, when the outside air mode is selected, the
inside/outside air switching door 30 is rotated in the
counterclockwise direction from the position of FIG. 1 by a
predetermined angle. Therefore, the packing members 31, 32 of the
inside/outside air switching door 30 press-contact the seal surface
around the inside air suction port 11. As a result, the
circumference opening 11a and the side openings 11b of the inside
air suction port 11 are fully closed by the outer wall plate 30b
and the side wall plates 30c, and the outside air suction port 12
is fully opened. In this case, by the operation of the blower fan
24, only outside air is sucked from the outside air suction port
12, and is blown toward the air conditioning unit.
[0036] In the inside air mode, the seal surface 14 and the seal
surface 15 provided in the inside/outside air switching box 10 are
need to be divided around the rotation shaft 30a (see FIG. 5).
Further, when the inside/outside air switching door 30 is not
elastically deformed as shown in FIG. 3A, a clearance CL (e.g., 0.5
mm) is provided between the seal member 30e formed on the rotation
shaft 30a and the inside/outside air switching box 10. Due to the
clearance CL, a sliding resistance during the rotation of the
inside/outside air switching door 30 can be reduced. However, when
the outside air pressure on the inside/outside air switching door
at the side of the outside air suction port 12 becomes higher due
to the ram pressure, outside air may be leaked from the clearance
CL as shown by arrow "b" in FIG. 4.
[0037] According to the first embodiment of the present invention,
the inside/outside air switching door 30 is elastically deformed by
the ram pressure, so that at least the portions of the side wall
plates 30c around the rotation shafts 30a are displaced away from
each other in the axial direction, and the rotation shafts 30a are
also displaced away from each other. By the displacement, each of
the seal members 30e press-contacts the inside/outside air
switching box 10. Because the seal members 30e press-contact the
inside/outside air switching box 10 in the axial direction, a
clearance between the inside/outside air switching door 30 and the
inside air switching box 10 can be sealed in the axial direction in
the inside air mode. Accordingly, in the inside air mode, a leakage
of outside air can be sufficiently restricted.
[0038] In the first embodiment, because both the side wall plates
30c are tilted to outside in the axial direction, relative to the
direction perpendicular to the outer wall plate 30b, a rotation
moment in the rotation direction of the inside/outside air
switching door 30, generated in the side wall plates 30c can be
increased. Therefore, the above-described displacements of both the
side wall plates 30c and the rotation shafts 30a can be made
easy.
[0039] Further, in the first embodiment, the outer wall plate 30b
is formed into the wave shape extending in the door rotation
direction. Therefore, the rigidity of the outer wall plate 30b in a
direction perpendicular to the rotation center axial line .phi.
relative to the ram pressure can be increased as compared with a
flat shaped outer wall plate. Accordingly, a bent amount of the
outer wall plate 30b in the direction perpendicular to the center
axial line .phi. can be made smaller as compared with that of the
flat shaped outer wall plate. Accordingly, the rotation moment
generated in the side wall plates 30c in the rotation direction of
the inside/outside air switching door 30 can be increased, and the
displacements, for displacing at least the portions of the side
wall plates 30c around the rotation shafts 30a away from each
other, can be made easy.
[0040] Further, in the first embodiment of the present invention,
because the outer wall plate 30b is formed into the wave shape,
air-blowing noise generated in the suction port 21 is reflected to
a side (i.e., right side in FIG. 4) opposite to the inside air
suction port 11, and a transmission of the air-blowing noise into
the passenger compartment can be reduced. More particularly, among
the wall surfaces Fl, F2 of the inside/outside air switching door
30, because wall surfaces Fl extending approximately horizontally
are provided in the outer wall plate 30b to face toward a side
opposite to the inside air suction port 11, the air-blowing noise
reflecting into the inside air suction port 11 can be greatly
reduced.
[0041] Further, in the first embodiment, because the noise can be
reduced using the wave-shaped outer wall plate 30b without using a
rib provided inside the outer wall plate 30b, it can restrict a
suction resistance of inside air from the inside air suction port
11. In addition, because the wall surfaces F2 extending
approximately in the up-down direction in FIG. 4 is tilted toward a
side opposite to the inside air suction port 11. Therefore, a
direction of air sucked in the arrow "d" in FIG. 4 can be smoothly
changed toward the suction port 21, and the suction resistance of
air can be further restricted.
[0042] Accordingly, in the first embodiment, the displacements for
displacing at least the portions of the side wall plates 30c around
the rotation shafts 30a to be separated from each other can be made
easy, and air-blowing noise can be reduced while suction resistant
of air can be restricted.
[0043] A second preferred embodiment of the present invention will
be now described with reference to FIGS. 5A and 5B. FIG. 5A shows a
natural state of a rotary-type inside/outside air switching door 30
without an elastic deformation, and FIG. 5B shows an elastic
deformation state of the inside/outside air switching door 30,
according to the second embodiment.
[0044] In the above-described first embodiment, the seal members
30e are provided on the rotation shafts 30a, the side wall plates
30c and the rotation shafts 30 are displaced due to the elastic
deformation of the inside/outside air switching door 30, and the
seal members 30e air-tightly contacts the inside/outside air
switching box 10 to seal therebetween in the axial direction.
However, in the second embodiment, as shown in FIGS. 5A and 5B, the
above-described seal members 30e may be omitted, and seal surfaces
30f parallel to the inner surfaces of the inside/outside air
switching box 10 are formed in the side wall plates 30c at
positions adjacent to the rotation shafts 30a. That is, the seal
surfaces 30f parallel to the inner surfaces of the inside/outside
air switching box 10 are provided in the side wall plates 30c only
at peripheral positions around the rotation shaft 30a. Accordingly,
when the side wall plates 30c and the rotation shafts 30a are
displaced due to the ram pressure, the seal surfaces 30f
press-contact the inside/outside air switching box 10 to seal
therebetween in the axial direction. Accordingly, the same effect
as the above-described first embodiment can be obtained.
[0045] Although the present invention has been fully described in
connection with the preferred embodiments thereof with reference to
the accompanying drawings, it is to be noted that various changes
and modifications will become apparent to those skilled in the
art.
[0046] For example, in the above-described embodiments, the seal
members 30e of the first embodiment or the seal surfaces 30f of the
second embodiment are disposed to directly press-contact the inner
surfaces of the inside/outside air switching box 10. However, an
elastically-deformable elastic material (e.g., porous foam such as
urethane foam) may be bonded on the seal members 30e or the seal
surfaces 30f. In this case, sealing performance between the
inside/outside air switching door 30 and the inside/outside air
switching box 10 in the axial direction can be further
improved.
[0047] In the above-described first and second embodiments, the
outer wall plate 30b is formed into the wave shape. However, a flat
plate may be used instead of the wave-like outer wall plate 30b. In
this case, by providing a rib on the inner surface of the flat
plate, the rigidity of the flat plate can be increased. Further,
the outer wall plate 30b may be formed into a circular arc shape
around the rotation shaft 30a.
[0048] In the above-described first and second embodiments, the
rotation shafts 30a are provided in the inside/outside air
switching door 30, and the bearing holes 13 are provided in the
inside/outside air switching box 10. However, the rotation shaft
30a may be provided in the inside/outside air switching box 10, and
the bearing holes 13 may be provided in the inside/outside air
switching door 30.
[0049] In the above-described first and second embodiments, each of
the packing members 31, 32 is formed into a plate like to be boned
onto the rib 30d of the inside/outside air switching box 10.
However, the packing members 31, 32 may be integrally molded with
the inside/outside air switching door 30 using an elastomer rubber
such as polypropylene type elastomer rubber, while the rotation
shafts 30a, the outer wall plate 30b and the side wall plates 30c
of the inside/outside air switching door 30 are molded using
polypropylene resin.
[0050] Such changes and modifications are to be understood as being
within the scope of the present invention as defined by the
appended claims.
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