JP2002275941A - Air conditioning apparatus for construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To take measures against cold climates without providing an outside air heater. SOLUTION: There is provided an air conditioning apparatus 40 for a construction machine, which is arranged in a cabin 9, and includes a heater box 42 having a fan heater 41 built therein, an air intake duct 44 for sucking air into the heater box 42 by using suction force of fans of the fan heater 41, and an exhaust port 45 for heating the air within the heater box 42 to a set temperature by a heating body of the fan heater 41 and then blowing the heated air into the cabin 9 by using blow-off force of the fan. The air intake duct 44 is comprised of a damper which can switch between at least two intake modes out of three, i.e., an inside air intake mode in which air only inside the cabin 9 is sucked to the heater box 42, an outside air intake mode in which only outside air is sucked, and a mixed air intake mode in which air both inside and outside the cabin is sucked.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for a construction machine, and more particularly to an air conditioner for a construction machine such as a small excavator having a narrow cabin.

[0002]

BACKGROUND OF THE INVENTION Recently, in the construction machine such as a small hydraulic excavators, in consideration of the comfort of the driver, often cabin is provided. This cabin is in an environment in which outside air is shut off, and an air conditioner is usually provided in the cabin.

For example, as an air conditioner mounted in a cabin of a small hydraulic excavator, a heater box having a built-in heater (commonly referred to as an inside air heater, the same applies to the following) and a fan is provided below a driver's seat. The air in the cabin is sucked into the heater box by the suction force of the fan, the suction air is heated to the set temperature by the heater, and then blown into the cabin by the blowout power of the fan, thereby removing the air in the cabin. Recirculation was common. In this case, the air in the cabin is recirculated, the air temperature is maintained at an appropriate temperature, and comfortable comfort is ensured.

[0004]

However, in cold regions, simply heating the air in the cabin with the inside air heater and recirculating the air in the cabin as described above does not remove the fogging of the cabin window glass, thereby lowering the visibility. May be. In such a case, it is effective to separately provide a heater (commonly referred to as an outside air heater; the same applies to the following description), introduce outside air, heat the outside air, and blow out the cabin. In addition, the ISO requires that a construction machine that can be used in such a cold region be equipped with an outside air heater. However, it has been difficult to secure a space for installing an outside air heater in addition to an inside air heater in a construction machine, particularly in a cabin of a small hydraulic excavator, and thus it has been difficult to take measures against cold regions.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an air conditioner for a construction machine capable of taking measures against a cold region without providing an outside air heater.

[0006]

According to the first aspect of the present invention,
A heater box disposed in the cabin and containing a heater for heating air and a fan, an air suction unit for sucking air into the heater box by suction of the fan, and a temperature set by the heater in the heater box. An air conditioner for a construction machine, comprising: an air blower that blows the air into the cabin by the blowing power of the fan after heating the air to the heater box. Suction air selection means that can switch between at least two suction states of an inside air suction state to perform suction, an outside air suction state to suck only outside air, and a mixed suction state to suck both air. is there.

[0007] According to this configuration, the intake air selection means of the air intake section sucks both the inside air suction state in which only the air in the cabin is sucked into the heater box and the outside air suction state in which only the outside air is sucked into the heater box. Switching between at least two of the mixed suction states,
For example, at the time of startup, air in the cabin is sucked into the heater box, heated by the heater in the heater box (in this case, functions as an inside air heater), and then returned to the cabin. Temperature of the cabin air by recirculation of the air is rapidly increased. If necessary, outside air is taken in, mixed with air from the cabin, heated by a heater in the heater box (in this case, functioning as an inside air heater and an outside air heater), and then blown into the cabin. This ensures more comfortable livability than the conventional example. Further, even in a cold region, the blowout removes fogging of the window glass of the cabin and improves visibility.

On the other hand, depending on the outside air condition in a cold region, only outside air is sucked into the heater box, and the heater in the heater box (in this case, functions as an outside air heater).
By being blown into the cabin after being heated in the above, cloudiness of the window glass of the cabin is removed and visibility is improved.

As described above, since the same heater functions as an inside air heater and / or as an outside air heater, it is not necessary to provide an outside air heater in the cabin in addition to the inside air heater. Excavator measures in cold regions are simplified.

According to a second aspect of the present invention, the intake air selecting means includes an inside air duct opening inside the cabin, an outside air duct opening outside the cabin, and a switching valve for switching between the two ducts according to an intake state. If provided, the inside air heater can be switched to the outside air heater with a single touch by simply adding a duct or the like, which is convenient.

According to a third aspect of the present invention, the switching valve includes:
If one of the switching states is a mixed suction state, and if an adjusting section that adjusts the opening area of both ducts is provided in this mixed suction state, the mixing ratio between the outside air and the air from inside the cabin is adjusted. Therefore, comfortable comfort is ensured, and even in a cold region, the glazing of the cabin is removed and visibility is improved.

According to a fourth aspect of the present invention, there is provided a heater box which is provided in a cabin and has a built-in heater and a fan for heating air, and a heater box which draws both air and outside air in the cabin by suction of the fan. And an air blower that heats the air in the heater box to a set temperature with the heater and then blows the air into the cabin with the blowing power of the fan.

According to this configuration, the air suction section creates a mixed suction state in which both the air in the cabin and the outside air are drawn into the heater box, so that the outside air is taken in and mixed with the air from the inside of the cabin. Then, the air is heated by a heater (functioning as an inside air heater and an outside air heater) in the heater box and then blown out into the cabin, so that a more comfortable livability than the conventional example is secured. In addition, even in cold regions,
The glazing of the window of the cabin is removed and visibility is improved.

As described above, since the same heater functions as an inside air heater and as an outside air heater, there is no need to provide an outside air heater in the cabin in addition to the inside air heater. In cold regions, it becomes easier.

According to a fifth aspect of the present invention, the air suction portion includes an inside air duct opening inside the cabin, an outside air duct opening outside the cabin, and an adjusting valve for adjusting the opening area of both ducts. In other words, the mixing ratio of the outside air and the air from inside the cabin is adjusted, ensuring more comfortable livability and improving the visibility of the cabin window glass even in cold climates. Is done.

According to the sixth aspect of the present invention, if a dustproof filter is provided in the outside air duct, dust contained in the outside air is removed, so that the air blown into the cabin is cleaned. Be transformed into

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIG. 1 is a view showing the entire configuration of a crawler type hydraulic excavator. A vehicle body of a hydraulic excavator as an example of a construction machine includes a lower traveling body 1,
And the upper revolving unit 2.
An attachment 3 for excavation is attached to the front of the vehicle so as to be able to undulate.

The lower traveling body 1 comprises left and right crawler frames 4 and crawlers (both are shown only on one side) 5,
The both-side crawlers 5 travel while being individually rotated and driven by the left and right traveling motors 7. The upper revolving unit 2 includes a revolving frame 8, a cabin 9, a machine room 10, and the like. The cabin 9 of the revolving frame 2 is a substantially closed structure that is shielded from the outside air to protect a driver from external noise and dust. In order to secure the livability, an air conditioner and the like described later are provided.

The excavation attachment 3 includes a boom 17,
A boom cylinder 18 that expands and contracts the boom by the hydraulic oil from the hydraulic pump, an arm 19, an arm cylinder 20 that rotates the arm 19, a bucket 21, and a bucket cylinder 22 that rotates the bucket Is provided.

FIG. 2 is a sectional view showing the internal arrangement of a cabin provided with the air conditioner of the crawler type hydraulic shovel according to the first embodiment of the present invention, and FIG. 4 is a partial perspective view of FIG.

FIG. 2 shows only the right and left sides (further rear part in FIG. 4), but windowpanes 30 are provided on all sides of the cabin 9, and through this windowpane 30, the driver can travel almost all around the outside. Can be visually recognized. Also within the cabin 9, and is equipped with a driver's seat 32 having a lateral operating lever 31, 31 for the driver to operate the air conditioner (the present as a feature of the present invention the lower part of the driver's seat 32 (Device) 40 is provided.

As shown in FIGS. 2 and 4,
A heater box 42 having a housing in which an electric heater with a fan (hereinafter, referred to as a fan heater) 41 as a heater is incorporated, and a substantially square-shaped intake port (air intake port) opened rightward toward the heater box 42 Part) 43, an intake duct (air intake part) 44 connected to the intake port 43,
A long hole-shaped exhaust port (air blowing section) 45 having a plurality of openings is provided on the front of the heater box 42.

The fan heater 41 forcibly circulates air in the cabin 9 or draws in outside air and heats it to a desired temperature and sends it to the cabin 9. And a temperature adjusting mechanism. This temperature adjustment mechanism performs automatic temperature adjustment by turning on and off a fan and a heating element in order to maintain the room temperature at a set temperature, and automatically turns off the power when overheating occurs. The heating capacity of the heating element of the fan heater 41 is determined in consideration of the volume in the cabin 9 and the assumed outside air temperature.

The intake duct 44 has, for example, a substantially rectangular cross section, and a substantially square inside air port 46 is opened at an appropriate position on the upper surface thereof so as to communicate with the cabin 9. Of the inside air duct.
A substantially square outside air opening 47 is provided on the right side of the intake duct 44.
Is opened to communicate with the outside of the cabin 9 (outside of the vehicle), thereby constituting an outside air duct of the intake air selecting means.

A louver 48 for preventing rain is provided outside the outside air opening 47, and a filter 49 having an appropriate dustproof mesh is provided inside the louver 48 for preventing rain. A heat insulator made of glass wool or the like for preventing dew condensation is attached to the inner surface or the outer surface of the intake duct 44 as necessary.

In order to adjust the opening and closing of the inside air opening 46 and the outside air opening 47, a common damper (intake air selection means, switching valve,
An adjusting section (adjusting valve) 50 is rotatably supported in the intake duct 44 around a horizontal pin 51 in the width direction thereof.
The turning operation of the damper 50 is performed by a manual operation of an operation lever 52 that penetrates through the intake duct 44 and protrudes into the cabin 9.

That is, at the position indicated by the solid line in FIG. 2, the damper 50 completely closes the inside air port 46, and at the position indicated by the two-dot chain line, the damper 50 completely closes the outside air port 47.
However, at the intermediate position, the damper 50 can partially close the inside air port 46 and the outside air port 47, respectively. This intermediate position can be set arbitrarily only by changing the inclination angle of the operation lever 52 of the damper 50 by the driver, and can be held at the set position.

The operation of the apparatus 40 will be described below.

Now, the damper 50 is located at the position shown by the two-dot chain line in FIG.
It is assumed that the side 7 is completely closed. In this state, the driver turns on the power supply of the present apparatus 40 and energizes the heating element of the fan heater 41 (in this case, it functions as an inside air heater). This energization heats the air in the heater box 42, and when the temperature reaches the set temperature, the fan of the fan heater 41 operates. Then, the air in the cabin 9 is sucked from the inside air port 46 into the heater box 42 via the intake duct 44 and the intake port 43 by the suction force of the fan. Then, the air heated by the heating element of the fan heater 41 is blown out of the heater box 42 into the cabin 9 via the exhaust port 45 by the blowing power of the fan. When the temperature reaches the set temperature, the heating element and the fan are appropriately turned on and off by the operation of the temperature adjusting mechanism of the fan heater 41 to maintain the set temperature. The power is turned off.

Then, when the driver tilts the operation lever 52 slightly to the right, the damper 50 rotates around the horizontal pin 51, and is located at an intermediate position between the positions indicated by the solid line and the two-dot chain line in FIG. Then, open the inside air port 46 to, for example, 40%,
So to open the external air inlet 47 side for example to 60%. In this state, the heater of the fan heater (which functions as an inside air heater and an outside air heater at this time) 41 is kept energized. This energization heats the air in the heater box 42, and the fan of the fan heater 41 continues to operate. Then, by the suction force of the fan, the air in the cabin 9 is sucked into the intake duct 44 via the inside air port 46, and the outside air is sucked into the intake duct 44 via the louver 48, the outside air port 47 and the filter 49. Here, the air in the cabin 9 and the outside air are almost uniformly mixed, and are sucked into the heater box 42 via the intake port 43. Then, the air heated by the heating element of the fan heater 41 is blown out of the heater box 42 into the cabin 9 via the exhaust port 45 by the blowing power of the fan. The operation of the temperature adjustment mechanism and the like of the electric heater 41 is the same as described above.

Further, when the driver tilts the operation lever 52 to the right, the damper 50 further rotates around the horizontal pin 51 to the position shown by the solid line in FIG.
6 is completely closed, and the outside air port 47 side is completely opened. In this state, the heater of the fan heater (which functions as an outside air heater in this case) 41 is kept energized. This energization heats the air in the heater box 42, and the fan continues to operate. Then, by the suction force of the fan, the outside air is sucked into the heater box 42 via the louver 48, the outside air port 47, the filter 49, the intake duct 44, and the intake port 43. And the fan heater 41
The air heated by the heating element is blown out of the heater box 42 into the cabin 9 via the exhaust port 45 by the blowing power of the fan. The operation of the temperature adjustment mechanism and the like of the fan heater 41 is the same as described above.

As described above, according to the first embodiment, the inside air suction state in which only the air in the cabin 9 is sucked into the heater box 42 by the driver's one-touch operation of the operation lever 52 of the damper 50 is achieved. In addition, it is possible to switch between at least two suction states of an outside air suction state in which only outside air is sucked and a mixed suction state in which both are sucked. Therefore, for example, at the time of starting, the cabin 9
The temperature of the air in the cabin 9 can be quickly raised by recirculating the air in the cabin. Further, by taking in part of the outside air as needed, it is possible to secure a more comfortable livability than the conventional example. On the other hand, in cold regions,
Since the outside air is taken into the cabin 9 and the window glass of the cabin 9 is clouded, the visibility can be improved.

However, depending on the outside air conditions (outside air temperature and humidity) in a cold region, it is not always necessary to introduce 100% of the outside air into the cabin 9. For example, the driver changes the inclination angle of the operating lever 52 of the damper 50. It can also be handled by changing the ratio of the outside air to the air in the cabin 9 (mixing ratio). In this case, a mixed suction state is created in which both the air in the cabin 9 and the outside air are sucked into the heater box 42, and this air-fuel mixture is heated in the heater box 42 and blown out into the cabin 9. Thereby, the window glass of the cabin 9 can be clouded and the visibility can be improved.

In the first embodiment, since the same fan heater 41 functions as an inside air heater and / or as an outside air heater, there is no need to provide an outside air heater in the cabin 9 in addition to the inside air heater. ,
Simplified countermeasures for cold weather in construction machinery and special small excavators.

Although the outside air port 47 is provided on the right side of the cabin 9 in the first embodiment, the outside air port 47 may be provided on the left side of the cabin 9. In that case, the configuration is left-right symmetric with the first embodiment.

(Embodiment 2) In the first embodiment, the outside air port for taking in outside air is provided on the side surface of the cabin. However, this outside air port is not necessarily provided on the side surface, and the bottom surface (floor plate) of the cabin is provided. May be provided. FIG.
FIG. 4 is a diagram showing an example of the configuration, and a part thereof is also shown in FIG. 3 and 4, elements common to the first embodiment are denoted by the same reference numerals, and different elements are denoted by dashes (') and redundant description is omitted as much as possible.

The air conditioner (the present device) 4 of the second embodiment
As shown in FIGS. 3 and 4, 0 ′ is a housing-shaped heater box 42 having a built-in electric fan heater 41 similar to that of the first embodiment, and is opened rightward toward the heater box 42. The heater 43 has an intake port 43, an intake duct 44 ′ connected to the intake port 43, and an exhaust port 45 opened in front of the heater box 42.

The intake duct 44 'has, for example, a rectangular cross section, and a substantially square inside air port 46 is provided at an appropriate position on the upper surface thereof.
Are opened to communicate with the interior of the cabin 9. A substantially square outside air opening 47 'is opened on the bottom side of the intake duct 44' so as to communicate with the outside of the cabin 9 (outside the vehicle).

Although a dustproof filter 49 'is provided above the outside air port 47', the louver for rain protection is not required in the second embodiment since the outside air port 47 'is provided downward. is there. A heat insulating material for preventing dew condensation is attached to the inner surface or the outer surface of the intake duct 44 'as needed.

In order to adjust the opening and closing of the inside air opening 46 and the outside air opening 47 ', a common damper 50' is rotatably supported around a horizontal pin 51 'in the width direction thereof in the intake duct 44'. I have. The turning operation of the damper 50 'is performed by manual operation of an operation lever 52' protruding into the cabin 9 through the intake duct 44 '.

That is, at the solid line position in FIG. 3, the damper 50 'completely closes the inside air port 46, and at the two-dot chain line position, the damper 50' completely closes the outside air port 47 '. However, at the intermediate position, the damper 50 ′ is
6 and the outside air opening 47 'can be partially closed, and the intermediate position can be held.

The operation of the device 40 'is the same as that of the first embodiment. According to the second embodiment, the driver operates the operation lever 52' of the damper 50 'by one-touch operation. Therefore, it is possible to switch between at least two suction states of an inside air suction state in which only air in the cabin 9 is sucked, an outside air suction state in which only outside air is sucked, and a mixed suction state in which both are sucked. The same operation and effect as those of the first embodiment can be obtained.

In the second embodiment, the outside air port 47 '
Is provided on the right bottom surface of the cabin 9, but the outside air opening 47 ′ may be provided on the left bottom surface of the cabin 9. In that case, the configuration is left-right symmetric with that of the second embodiment.

In the first and second embodiments, the heater is, for example, an electric fan heater, but may be of a type that circulates engine cooling water. Further, the heater does not necessarily have to be a fan heater, and a heater and a fan may be separately provided.

In the first and second embodiments. Shy mouth 4
6 and a damper 5 common to the outside air opening 47 (47 ')
Although it is 0 (50 '), a separate damper may be provided. In such a case, if both dampers are linked, the same operation as above can be performed. Further, the damper 50
As the operation method of (50 '), a mechanical or electric remote control may be adopted. In this case, the restriction on the arrangement of the damper 50 (50') itself is reduced.

In the first and second embodiments, a small hydraulic excavator most suitable for the present invention has been described. However, the scope of the present invention is not limited to this, and the present invention is applicable to other construction machines such as wheel cranes. Is of course applicable as well. In such a case, it is conceivable to adopt a configuration capable of cooling and heating as far as the space in the cabin permits. Further, the present invention can be applied to a construction machine having only an existing inside air heater by remodeling work.

[0047]

According to the first aspect of the present invention, the temperature of the air in the cabin can be quickly increased by, for example, recirculating the air in the cabin. Further, by taking in part of the outside air as needed, it is possible to secure more comfortable livability than the conventional example. Further, even in a cold region, the visibility of the cabin can be improved by removing the fogging of the window glass of the cabin.

On the other hand, depending on the outside air condition in a cold region, it is possible to improve the visibility by taking only the outside air into the cabin to remove the fogging of the window glass of the cabin.

By making the same heater function as an inside air heater and / or as an outside air heater, there is no need to provide an outside air heater in the cabin in addition to the inside air heater. Can easily take measures against cold regions.

According to the second aspect of the present invention, the inside air heater can be switched to the outside air heater with a single touch simply by adding a duct or the like.

According to the third aspect of the present invention, since the mixing ratio of the outside air and the air from inside the cabin can be adjusted, more comfortable livability can be secured, and the windowpane of the cabin can be secured even in a cold region. And the visibility can be improved.

According to the fourth aspect of the present invention, by taking in part of the outside air, more comfortable livability can be secured than in the conventional example. In addition, even in a cold region, the window glass of the cabin can be defrosted, and the visibility can be improved.

Since the same heater functions as an inside air heater and as an outside air heater, it is not necessary to provide an outside air heater in the cabin in addition to the inside air heater. Earth measures can be taken easily.

According to the fifth aspect of the invention, by adjusting the mixing ratio of the outside air and the air from inside the cabin,
Further, comfortable comfort can be secured, and even in a cold region, the window glass of the cabin can be clouded to improve visibility.

According to the sixth aspect of the invention, the dust contained in the outside air is removed, and the air blown into the cabin is cleaned, so that the livability can be further improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire configuration of a crawler type hydraulic excavator.

FIG. 2 is a cross-sectional view showing an internal arrangement of a cabin provided with the air conditioner of the crawler hydraulic excavator according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view showing an internal arrangement of a cabin provided with an air conditioner of a crawler type hydraulic shovel according to a second embodiment of the present invention.

FIG. 4 is a partial perspective view of FIGS. 2 and 3;

[Explanation of symbols]

9 Cabin 30 Window glass 40, 40 'Air conditioner (this device) 41 Fan heater (heater) 42 Heater box 43 Intake port (air intake section) 44, 44' Intake duct (air intake section, intake air selection means, inside air) Duct, outside air duct) 45 Exhaust port (air blowing section) 46 Inside air port (air suction section, suction air selection means, inside air duct) 47, 47 'Outside air port (air suction section, suction air selection means, outside air duct) 49 Filter 50, 50 'damper (intake air selection means, switching valve, adjustment unit, switching valve)

Claims (6)

[Claims] 1. A heater box disposed in a cabin and containing a heater for heating air and a fan, an air suction unit for sucking air into the heater box by suction of the fan, and air in the heater box. An air conditioner for a construction machine, comprising: an air blower that blows into the cabin by a blowout power of the fan after heating to a set temperature by the heater; Inside air inhalation state in which only air of
An air conditioner for a construction machine, comprising: intake air selection means that can switch between at least two of an outside air suction state in which only outside air is sucked and a mixed suction state in which both are sucked. 2. The intake air selecting means includes an inside air duct opening inside the cabin, an outside air duct opening outside the cabin, and a switching valve for switching between the two ducts according to an intake state. Item 6. An air conditioner for a construction machine according to Item 1. 3. The construction according to claim 2, wherein the switching valve has a mixed suction state as one of the switching states, and has an adjusting portion for adjusting an opening area of both ducts in the mixed suction state. Machine air conditioner. 4. A heater box provided in the cabin and containing a heater for heating air and a fan, and an air suction unit for sucking both air and outside air in the cabin into the heater box by suction of the fan. An air blower for heating the air in the heater box to a set temperature with the heater, and then blowing the air into the cabin with the blowing power of the fan. 5. The air intake section includes an inside air duct opening inside the cabin, an outside air duct opening outside the cabin, and an adjusting valve for adjusting an opening area of both ducts. An air conditioner for a construction machine according to the above. 6. The air conditioner for a construction machine according to claim 2, wherein a dustproof filter is interposed in the outside air duct.