JP4859621B2 - Air conditioner for vehicles - Google Patents

Description

  The present invention relates to a vehicle air conditioner used for air conditioning in a passenger compartment.

  A vehicle air conditioner that cools and heats the interior of a vehicle and provides a comfortable interior space has a configuration in which various dampers are installed in a casing that houses a blower fan, an evaporator, a heater core, and the like to form an air flow path. Is done. The dampers installed in the casing include an inside / outside air switching damper that switches the air to be introduced, an air mix damper that is used to control the air conditioning temperature, a face outlet and a foot outlet depending on the mode of blowing the conditioned air There are also air outlet dampers (such as face dampers) for opening and closing the defrost air outlet.

  The damper described above includes a damper shaft integrated with a plate-shaped damper main body, and the damper shaft is rotatably supported by a bearing portion of the casing. In such a plate damper structure, when the damper is in the open position and the flow path is opened, air flows through a gap formed between the surfaces of the damper shaft and the bearing portion. May cause annoying noises. This abnormal noise is considered to be caused by air flowing at high speed through the gaps described above. In addition, the inter-surface gap which is a problem here is necessary as a measure against thermal expansion in the case of being affected by a temperature change caused by an air conditioning operation.

As a countermeasure against the above-mentioned abnormal noise, it is known to provide a damper shaft with a packing or an insulation to shield the wind. However, it has been pointed out that this countermeasure against abnormal noise causes an increase in cost and an increase in damper operating force.
There is also a method of reducing noise by suppressing the noise by increasing the clearance between the damper shaft and the bearing portion. However, if this method is adopted, the air flow rate that passes through the gap between the surfaces increases, so when adjusting the air distribution in each air conditioning mode, it is necessary to consider the amount of wind leakage in the gap in addition to the damper rotation angle. Because it comes, it is not preferable.
Furthermore, there is a method of suppressing the air flow rate flowing through the inter-surface gap by setting the inter-surface gap between the damper shaft and the bearing portion small. However, when this method is adopted, there is a problem that the damper shaft and the bearing portion are likely to interfere with each other due to the thermal influence due to the temperature change of the air conditioning.

On the other hand, in order to improve the rotational state of the damper, a vehicle air-conditioning unit has been proposed in which the bearing portion has a cylindrical shape and the shaft portion has a sliding contact surface and a relief surface. In this case, the shaft portion is formed with a plurality of concave portions at predetermined intervals on both sides along the longitudinal direction, but the positional relationship with the bearing portion is unknown. Furthermore, the formation of such recesses is likely to cause a cavity tone. (For example, see Patent Document 1)
JP 2004-26069 A (see FIG. 2)

  As described above, in a damper that is in an open position during operation of the vehicle air conditioner and has a flow path opened, it is caused by air flowing through a gap formed between the surfaces of the damper shaft and the bearing portion. Since the generation of the annoying abnormal noise that occurs is a problem, it is desirable to provide a more comfortable vehicle interior space by preventing or suppressing the generation of the abnormal noise. In particular, by increasing costs by increasing the number of parts, increasing damper operating force by packing, etc., increasing the air flow rate through the clearance between surfaces, and preventing interference between the damper shaft and the bearing due to thermal effects In addition to ensuring good operability at low cost, it is possible to provide a quiet and comfortable vehicle interior space by preventing or suppressing abnormal noise caused by the air flowing through the gap formed between the surface of the damper shaft and the bearing portion. It would be desirable to provide a vehicle air conditioner that can be used.

  The present invention has been made in view of the above circumstances, and the object thereof is to ensure good operability at low cost and to flow through a gap formed between the surfaces of the damper shaft and the bearing portion. An object of the present invention is to provide a vehicle air conditioner that can prevent or suppress the generation of abnormal noise caused by air and can provide a quiet and comfortable vehicle interior space.

In order to solve the above problems, the present invention employs the following means.
In the vehicle air conditioner according to the present invention, the flow of air that is conditioned through the casing is controlled by opening / closing operation of the damper, and the damper shaft that rotates integrally with the damper has a bearing surface of the casing. In a vehicle air conditioner that is rotatably supported with an inter-surface gap formed therebetween, irregularities that repeat regularly or irregularly on the outer peripheral surface of the damper shaft that make the inter-surface gap uneven in the longitudinal direction The rib is located in a range that always faces the bearing surface and forms the inter-surface gap within the operating range of the damper.

  According to such a vehicle air conditioner, since the rib provided on the outer peripheral surface of the damper shaft is located in a range that always faces the bearing surface and forms a gap between the surfaces within the operation range of the damper, The inter-surface gap is not uniform in the longitudinal direction (axial direction) of the damper shaft. For this reason, the flow of air passing through the inter-surface gap is disturbed in the longitudinal direction of the damper shaft, and generation of uniform vortices in the longitudinal direction can be prevented. Further, the rib in this case can be formed integrally with the damper shaft, and further, the inter-surface gap can be set to an optimum value in consideration of the thermal effect.

In the above invention, the rib preferably has an inclination in accordance with the inclination of the bearing surface, whereby the rib can be provided in consideration of a draft gradient during molding.
In the above invention, it is preferable that the rib is provided in a portion that has been stolen.

According to the above-described present invention, the rib provided on the outer peripheral surface of the damper shaft makes the inter-surface gap non-uniform in the longitudinal direction (axial direction) of the damper shaft, so that the air flow passing through the inter-surface gap is Disturbed in the longitudinal direction of the shaft, the generation of uniform vortices in the same direction is prevented. For this reason, generation | occurrence | production of the abnormal noise resulting from the flow of the air which passes the clearance gap between surfaces is prevented or suppressed, and it becomes possible to make it quiet and comfortable vehicle interior space.
In particular, the ribs described above can be molded integrally with the damper shaft, so there is no increase in cost due to an increase in the number of parts, an increase in damper operating force due to packing, etc. Since the value can be easily set, it is possible to prevent the interference due to an increase in the flow rate of air passing therethrough and the influence of heat, and to ensure good operability at low cost.

Hereinafter, an embodiment of a vehicle air conditioner according to the present invention will be described with reference to the drawings.
A vehicular air conditioner (hereinafter referred to as an “air conditioner”) is roughly divided into an air conditioner unit that performs air conditioning such as cooling and heating, a refrigerant system for supplying refrigerant into the air conditioner unit during cooling operation, It comprises a heating source system for supplying engine cooling water as a heat source into the air conditioning unit during operation, and a control unit that controls the operation of the entire apparatus.

The refrigerant system is a refrigerant circuit that supplies low-temperature and low-pressure liquid refrigerant to an evaporator in an air conditioning unit, which will be described later. The compressor compresses the gas refrigerant, the condenser that condenses the gas refrigerant, and the high-temperature and high-pressure liquid refrigerant is decompressed and reduced. An expansion valve that expands and supplies a low-temperature and low-pressure liquid (mist-like) refrigerant to the evaporator.
The heating source system is a hot water circuit that supplies high-temperature engine cooling water serving as a heat source to a heater core in an air conditioning unit to be described later, and a part of the hot water from the engine cooling water system circulating between the engine and the radiator. Is configured to be introduced into the heater core by performing flow rate control using a water valve.

  The control unit CP performs operation control of the air conditioning unit 10, the refrigerant system, and the heating source system constituting the air conditioner. Usually, a control circuit is incorporated in an operation panel on which the occupant performs various settings. It is arranged at the center of the instrument panel in the passenger compartment. In this control unit CP, the operation mode selection switching by opening / closing operations of various dampers, the selection switching of introduced air by switching operation of the inside air / outside air switching damper, the air volume switching operation of the blower fan, the desired temperature setting operation, etc. are performed. Can do.

Here, the structure of the general air conditioning unit 10 is demonstrated based on FIG.
The air conditioning unit 10 is generally called an HVAC (heating ventilation air-conditioning) module, and has a hollow main body cover 11 as a casing. Inside the main body cover 11 is a flow path for air to be conditioned, and devices such as the blower fan 31, the evaporator 32, and the heater core 33 are stored and installed in order from the upstream side of the flow path.

On the outer surface of the main body cover 11, the outside air introduction port 12 and the inside air introduction port 13 which are air intakes for selectively introducing air outside the vehicle compartment (outside air) or air inside the vehicle compartment (inside air) are air-conditioned. A defrost outlet 14, a face outlet 15, and a foot outlet 16 are opened as air outlets for blowing out into the vehicle interior in accordance with an operation mode in which cold air, warm air, or the like is selected.
In the following description, air outside the vehicle compartment (outside air) and air inside the vehicle compartment (inside air) introduced from the air intake are collectively referred to as “introduction air”.

Inside the main body cover 11, an inside / outside air switching damper 21 that performs selective switching of the introduced air, an air mix damper 22 that controls the temperature by adjusting the amount of introduced air that passes through the heater core 33, and an air outlet are installed. Further, a defrost damper 23, a face damper 24, and an outlet damper of the foot damper 25 are disposed. The various dampers used here are all cantilever dampers.
Various sensors (not shown) are installed inside the main body cover 11 as necessary.

FIG. 4 is a cross-sectional view of a main part showing another configuration example of the HVAC module. In the illustrated air conditioning unit 10A, a butterfly-shaped air mix damper 40 is employed as a damper for adjusting the amount of introduced air that passes through the heater core 33.
In this case, if the air mix damper 40 is operated to reach the maximum heating position (M / H) indicated by the solid line, the entire amount of the introduced air is heated through the heater core 33 as indicated by the solid arrow in the figure. . However, if the air mix damper 40 is operated to reach the maximum cooling position (M / C) indicated by the imaginary line, the entire amount of introduced air flows bypassing the heater core 33 as indicated by the imaginary line arrow in the figure. In addition, the code | symbol 11A in a figure is the main body cover used as a casing.

Hereinafter, the characteristic structure of this invention is demonstrated about various dampers used for HVAC modules like the air conditioning units 10 and 10A of the air conditioning apparatus mentioned above.
FIG. 1 is a schematic diagram showing a butterfly-shaped damper 40. For example, the air-conditioning unit 10A of FIG. 4 is used as an air mix damper. The damper 40 is, for example, a resin molded product, and includes a damper main body 41 that is a plate-like member, and a damper shaft 42 that rotates integrally with the damper main body 41. And this damper 40 is rotatably supported by the bearing part 17 provided in the proper place of the main body cover 11A used as a casing.

The damper 40 shown in FIG. 1 (a) rotates around a damper shaft 42 supported by the bearing portion 17, and swings within the range from the maximum cooling position (M / C) to the maximum heating position (M / H). To do. Such a damper shaft 42 enables smooth rotation in consideration of a temperature change or the like, so that an appropriate inter-surface gap is provided between the outer peripheral surface of the damper shaft 42 and the bearing surface 17a of the bearing portion 17. Is formed. A rib 43 is provided on the outer circumferential surface of the damper shaft 42 so as to protrude in a substantially sawtooth shape outward in the radial direction and to make the inter-surface distance non-uniform with the bearing surface 17a continuous in the longitudinal direction (axial direction). ing.
The rib 43 is always located in a range in which a gap between the surfaces is formed facing the bearing surface 17a within the operation range of the damper 40 in which the damper main body 41 rotates. That is, the rib 43 protrudes at a position that always rotates opposite to the bearing surface 17 a within the rotation range of the damper main body 41.

For example, as shown in FIG. 1B, the rib 43 described above has a saw-tooth shape that repeats regular triangular irregularities continuously in the axial direction of the damper shaft 42, and the saw-tooth irregularities formed on the rib 43. Between the surface and the bearing surface 17a, an inter-surface gap having a non-uniform gap size in the longitudinal direction is formed. That is, the inter-surface gap is the smallest at the top of the convex portion of the rib 43 and the largest at the bottom of the concave portion.
By the way, the ribs 43 described above are not limited to the irregularities of the triangles that repeat regularly, but of course the irregularities of irregular triangles, as well as other cross-sectional shapes such as semicircles and ellipses, or different plural shapes Irregularities that repeat regularly or irregularly, such as a combination of cross-sectional shapes, may be used.

  In the damper 40 configured as described above, the ribs 43 provided on the outer peripheral surface of the damper shaft 42 are located in a range in which an inter-surface clearance is always formed facing the bearing surface 17a within the operation range of the damper 40. Therefore, the inter-surface gap is not uniform in the longitudinal direction (axial direction) of the damper shaft 42. For this reason, the flow of air passing through the inter-surface gap is disturbed in the longitudinal direction of the damper shaft 42, and therefore, generation of a uniform vortex in the longitudinal direction can be prevented. Further, the rib 43 in this case can be molded integrally with the damper shaft 42, and the inter-surface gap can be set to an optimum value.

FIG. 2 shows the above-described rib 43 of the present invention as a cantilever damper that is used in a blow mode damper that is attached to each outlet and opens and closes, such as a defrost damper 23, a face damper 24, and a foot damper 25. It is a schematic diagram which shows the case where it applies.
The damper 40A has a shape in which a damper body 41A is provided on one of the damper shafts 42A. The damper shaft 42A is provided with a sawtooth-shaped rib 43 that repeats regular triangular irregularities continuously in the axial direction of the damper shaft 42A. The rib 43 always faces the bearing surface 17a within the operation range of the damper 40A, and is located in a range that forms an inter-surface gap that is non-uniform in the longitudinal direction.

  Also in the damper 40A configured as described above, the rib 43 provided on the outer peripheral surface of the damper shaft 42A is positioned in a range in which an inter-surface clearance is always formed facing the bearing surface 17a within the operation range of the damper 40A. Therefore, the inter-surface gap is not uniform in the longitudinal direction (axial direction) of the damper shaft 42A. For this reason, the flow of air passing through the inter-surface gap is disturbed in the longitudinal direction of the damper shaft 42A, and therefore, generation of a uniform vortex in the longitudinal direction can be prevented.

Next, a specific configuration example of the above-described butterfly-shaped damper 40 will be described with reference to FIGS.
The damper 40 is an integrally molded part of resin, and a damper shaft 42 is provided across the short side direction of the damper main body 41 having a substantially rectangular shape. The damper shaft 42 includes a shaft sliding surface 42a having a substantially semicircular cross section, and a rib 43 'is provided on the shaft sliding surface 42a.

  In the illustrated configuration, as shown in FIG. 6, a meat stealing recess 44 is provided on the shaft sliding surface 42 a of the damper shaft 42. Therefore, in this embodiment, the rib 43 ′ is formed using the meat stealing recess 44. Note that reference numeral 45 in the drawing is an insulation provided at an appropriate position of the damper main body 41.

By dividing the longitudinal direction of the damper shaft 42, a plurality of the meat stealing recesses 44 are intermittently provided (ten in the illustrated example).
Each recess 44 has a rectangular shape, and ribs 43 'are formed in the longitudinal direction so that the rectangle is divided into two in the circumferential direction. Therefore, as shown in FIG. 7, the rib 43 ′ is intermittently uneven in the longitudinal direction, like the intermittent recess 44. In the illustrated example, three concave grooves each having a substantially semicircular cross section are formed for each concave portion 44. That is, since the rib 43 ′ described above is provided in a portion remaining after forming the meat stealing recess 44, it is possible to form irregularities without protruding from the shaft sliding surface 42 a of the damper shaft 42. Become. As a result, the shaft sliding surface 42a becomes a substantially semicircular shape without a convex portion, so that the damper main body 41 can be rotated more smoothly during the opening / closing operation.

By the way, the main body cover 11 serving as the casing described above is usually a molded product of resin. For this reason, a split surface perpendicular to the damper shaft 42 (shown by a one-dot chain line in FIG. 10 and FIG. 11) is set for convenience of die cutting. 42 is not always parallel.
Therefore, in the case of the bearing surface 17b having the inclination of the draft, it is preferable to provide ribs 43A and 43B that are inclined in accordance with the inclination of the bearing surface 17b as shown in FIGS. Such ribs 43A and 43B are optimum in consideration of the draft gradient during molding.

The rib 43A shown in FIG. 10 is employed when the damper shaft 42 is straight with respect to the bearing surface 17b having an inclined surface. The rib 43A is provided so as to be inclined with respect to the outer peripheral surface of the damper shaft 42 orthogonal to the dividing surface so that the tip of the convex portion is substantially parallel to the inclination of the bearing surface 17b.
For this reason, the gap between the damper shaft 42 and the bearing surface 17b is substantially uniform between the tip of the convex portion of the rib 43A and the bearing surface 17b, but the longitudinal direction is uneven due to the unevenness of the rib 43A. That is, the rib 43A in this case is provided by inclining the rib itself with respect to the straight damper shaft.

The rib 43B shown in FIG. 11 is employed when the damper shaft 42B has an outer peripheral surface substantially parallel to the bearing surface 17b having an inclined surface. The rib 43B is provided at the same height from the outer peripheral surface of the damper shaft 42B substantially parallel to the bearing surface 17b so that the tip of the convex portion is substantially parallel to the inclination of the bearing surface 17b.
For this reason, the inter-surface clearance between the damper shaft 42B and the bearing surface 17b is substantially uniform between the tip of the convex portion of the rib 43B and the bearing surface 17b, but the longitudinal direction is non-uniform due to the unevenness of the rib 43B. That is, the rib 43B in this case is provided with the rib 43B by inclining the damper shaft 42B side.

  According to the present invention described above, the ribs 43 provided on the outer peripheral surface of the damper shaft 42 make the inter-surface gap non-uniform in the longitudinal direction of the damper shaft 42. For this reason, the air flow passing through the inter-surface gap is disturbed in the longitudinal direction of the damper shaft 42, and uniform vortices are prevented from being generated in the longitudinal direction. The generation of abnormal noise can be prevented or suppressed.

  FIG. 12 is a graph of experimental results showing the effect of suppressing the occurrence of abnormal noise according to the present invention, where the horizontal axis represents frequency (Hz) and the vertical axis represents sound pressure level (dB). According to this experimental result, the sound pressure level around α Hz is abnormally high in the conventional structure with a solid line display without ribs. However, it can be seen that by providing the ribs 43 described above, the sound pressure level around α Hz decreases by ΔdB as shown by the broken line in the figure, thereby providing a quiet and comfortable vehicle interior space. In this experiment, the frequency α at which the sound pressure level is abnormally increased and noise is generated is about 1000 Hz.

Further, since the rib 43 described above can be molded integrally with the damper shaft 42, there is no increase in cost due to an increase in the number of parts, an increase in damper operating force due to packing or the like, and an inter-surface gap in consideration of thermal effects. Since it is possible to easily set the optimum value, it is possible to prevent the interference due to the increase in the flow rate of air passing through and the influence of heat, and to ensure good operability at low cost.
In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary of this invention, it can change suitably.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows one Embodiment of the air conditioning apparatus for vehicles which concerns on this invention, (a) is a schematic diagram which shows the butterfly type damper provided with the rib, (b) is AA sectional drawing of (a). . It is a figure which shows one Embodiment of the air conditioning apparatus for vehicles which concerns on this invention, and is a schematic diagram which shows the cantilever damper provided with the rib. It is sectional drawing which shows the structural example of the air conditioning unit in a vehicle air conditioner. It is principal part sectional drawing which shows the other structural example of the air conditioning unit in a vehicle air conditioner. It is a top view which shows the specific structural example of a butterfly type damper. FIG. 6 is a bottom view of FIG. 5. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is DD sectional drawing of FIG. It is sectional drawing which shows the rib employ | adopted when a damper shaft is straight with respect to the bearing surface which has an inclined surface. It is sectional drawing which shows the rib employ | adopted as a damper shaft whose outer peripheral surface is substantially parallel with respect to the bearing surface which has an inclined surface. It is a graph of the experimental result which shows the effect of this invention.

Explanation of symbols

17 Bearing portion 17a, 17b Bearing surface 40, 40A Damper 41, 41A Damper main body 42, 42A, 42B Damper shaft 43, 43 ', 43A, 43B Rib

Claims (3)

The flow of air conditioned through the inside of the casing is controlled by the opening / closing operation of the damper, and the damper shaft that rotates integrally with the damper forms an inter-surface gap between the bearing surface of the casing and rotates. In a vehicle air conditioner that is supported,
Provided on the outer peripheral surface of the damper shaft is a rib that is irregularities that repeat regularly or irregularly to make the inter-surface gap uneven in the longitudinal direction, and the rib always faces the bearing surface within the operating range of the damper The vehicle air conditioner is located in a range where the inter-surface gap is formed.   The vehicle air conditioner according to claim 1, wherein the rib has an inclination in accordance with an inclination of the bearing surface. The air conditioning apparatus for a vehicle according to claim 1 or 2, wherein the rib is provided in a portion left after the meat is stolen.

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