JP2006027380A - Window cleaning device for cab of construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform effectively the cleaning of a cab window continuously while the machine is in operation without consuming extra power. <P>SOLUTION: A duct 14 having an intake hole 14a in the downstream of a cooling fan 12 is installed for utilizing the exhaust air after cooling a radiator 8 by a cooling fan 12 coupled directly to an engine 6 as an air stream for air curtain supplied to an air jet 9, extended to a roof 16 from the rear wall 15 of the cab 4 upon passing the part of the passage of an upper revolver 2 from the upper part of a building 5, and connected with the air jet 9 provided in a position over a front window 8, and thereby the air curtain for cleaning is generated by forming a down-flow air stream in the laminar flow state in such a way as tightly attaching to the outside surface of the front window 8 from the air jet 9. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for cleaning a driver's cab window that is provided in a construction machine that performs work in an environment where dust or the like is scattered, and that keeps the driver's cab window free from dirt.

  As a construction machine, for example, a hydraulic excavator is mainly operated in the field, and since it performs operations such as excavation of earth and sand, it is placed in a situation where dust and the like are scattered around. The upper swing body in the hydraulic excavator is provided with excavation means, and operations such as excavation of earth and sand are performed by operating the excavation means. A driver's cab is provided at a position along the excavation work means in the upper swing body, and the operator operates each mechanism unit including the excavation work means in this cab. A driver's seat on which an operator is seated is installed inside the operator's cab, and in order to ensure an external view while seated on this driver's seat, the front window, left and right Side windows are formed on both sides, and rear windows are formed on the rear side.

  Since operations such as excavation of earth and sand are performed in front of the operator seated in the driver's seat, almost the entire front surface of the operator's cab is a front window, which makes the operator wide from diagonally upward to diagonally downward. A field of view is secured. The forward visual field including the diagonally upward to diagonally downward direction is extremely important for the operator who operates the machine. When the front window is soiled and difficult to see, the visibility in the forward area is deteriorated, and the operation of the excavating work means is reduced. As a result, inconveniences such as not only the smoothness, safety, etc. of the device being impaired, but also operator fatigue are increased. A wiper is attached to the front window. When this wiper is operated, dirt on the front window can be removed, but the range that can be cleaned with the wiper is limited.

Considering the above points, in Patent Document 1, an air curtain is formed on the surface of the window by flowing compressed air along the surface of the window, so that a cleaning function is exhibited so that dust or the like does not adhere to the window. What has been configured to be proposed has been proposed. An air compressor is provided to supply the compressed air, and the air compressed by the air compressor is formed so as to form a downward flow from the upper side of the cab along the outer surface of the window. An electromagnetic valve is provided to control the air flow.
Japanese Utility Model Publication No. 6-45878

  By the way, when it is configured to supply compressed air from the air compressor as in the prior art described above, a power source for driving the air compressor is required. In hydraulic excavators and other construction machines, an engine is mounted and a battery is also mounted. Therefore, the engine or the battery is the target of the power source. Since construction machines always operate in an environment in which dust and the like are scattered, window cleaning usually has to be performed almost continuously from the start to the end of the operation while the machine is in operation. Therefore, when the engine is used as a power source for the air compressor, the operating efficiency of the machine itself is lowered by the amount of energy used in the air compressor. In addition, when a battery is used as a power source, the power consumption increases, so that there is a problem that the battery is consumed heavily. Moreover, installing an air compressor for window cleaning restricts the space by the occupied space, and the air compressor may break down, so there is a burden in terms of maintenance. growing.

  The present invention has been made in view of the above points, and an object of the present invention is to be able to clean windows effectively continuously while the machine is operating without consuming special power. There is to do.

  In order to achieve the above-described object, the present invention provides an apparatus for cleaning an operator cab window that forms an air curtain along an outer surface of a window glass attached to an operator cab of a construction machine, A duct having one end opened is provided on the downstream side of the cooling fan that circulates the cooling air through the heat exchanger, and the duct is routed to the upper position of the window, and the other end of the duct has a predetermined length in the width direction of the window. This is characterized in that an air ejection part having a thickness is connected.

  In principle, heat exchangers such as radiators, oil coolers, and intercoolers are always in operation during machine operation. In this heat exchanger, air is forcibly circulated by a cooling fan, and the air flowing downstream of the cooling fan is exhausted as it is. Therefore, this exhaust is used to form an air curtain for cleaning the window surface. Here, the air curtain for preventing dust and the like from adhering to the window glass is a downflow, and it is sufficient that air flows continuously in a laminar flow state along the surface of the window. There is no need to increase the downstream flow. In particular, as long as dust or the like is in a substantially floating state, the flow rate is slow and a thin air curtain is formed on the surface of the window, and it does not adhere directly to the window.

  The flow speed on the downstream side of the cooling fan is not uniform, and the flow speed varies greatly depending on the part. Therefore, it is desirable to open the duct at a part where the flow velocity is the fastest downstream of the cooling fan. Further, since windows are formed in the operator's cab in the front and rear and left and right directions, the window in which the air curtain is formed is determined based on the necessity of the visual field during work. Since the operator always needs to view the excavation means, the window in which the air curtain is formed is at least the front window, and the air jetting part is opened to cover the entire width of the front window. . Of course, an air curtain may be formed on the side window or the like.

  Depending on the working environment and depending on the working mode, there is a situation in which no dust or the like is generated or the window is not damaged. And since the air curtain supplied to a window passes through a heat exchanger, it is common that it is in a high temperature state compared with outside air. For this reason, the window is heated, and depending on the state of the outside air, the air may be slightly fluctuated by flowing air. Considering the above points, it is desirable to be able to select not to form an air curtain. For this purpose, an opening / closing means for switching between a state in which the flow of air supplied from the cooling fan is supplied to the air ejection part and a state in which the air is discharged to the outside air can be provided in the middle of the duct.

  Further, since the air supplied to the surface of the window as an air curtain is hot, it can be quickly thawed by the air curtain when dew condensation occurs on the window glass, for example, in winter or cold areas. Furthermore, when the temperature difference between the inside and outside of the cab is large, condensation may form on the window glass, and in order to remove fogging due to this condensation, a high-temperature air curtain after heat exchange by the heat exchanger It is valid.

  As described above, by utilizing the air flow downstream of the cooling fan as a window air curtain, the window of the cab is continuously cleaned as long as the machine is operating without consuming energy. Can be done.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, FIGS. 1 and 2 show a hydraulic excavator as an example of a construction machine. Here, FIG. 1 is a front view of the excavator, and FIG. 2 is a plan view of the excavator with the excavation work means omitted.

  In these figures, 1 is a lower traveling body and 2 is an upper swing body. The lower traveling body 1 has a pair of crawler-type traveling means. An excavation work means 3 such as earth and sand comprising a boom 3 a, an arm 3 b, and a bucket 3 c is attached to the upper swing body 2, and a cab 4 is installed in line with the excavation work means 3. Further, a building 5 is formed in the rear part of the cab 4, and an engine 6 (two engines 6 are illustrated in the drawing is illustrated) and a hydraulic pump 7 are installed inside the building 5. Has been. 1 and 2 show the devices such as the engine 6 exposed, these devices are covered with a building cover.

  The hydraulic excavator has a configuration higher than the outline, and the operator performs operation control of the machine, that is, excavation work means 3 in the operator's cab 4 installed in the upper swing body 2, Further, in order to load the excavated soil on the dump truck, an operation of turning the upper traveling body 2 with respect to the lower traveling body 1 or causing the lower traveling body 1 to travel is performed. For this purpose, although not shown in the drawing, the driver's seat is provided inside the operator's cab 4, and an operation lever is provided at the front position and the left and right side positions when the operator is seated on the driver's seat. Operating means such as operating pedals and switches are installed.

  Here, as described above, in order to control the operation of the machine, the operator must be able to see the outside from inside the cab 4. For this purpose, windows are provided before and after the cab 4 and on the left and right. In particular, the front view of the operator seated in the driver's seat is extremely important for the purpose of operating the excavation work means 3 and the like. Moreover, since the excavation work means 3 operates in the vertical direction, the front window 8 (see FIG. 4) formed in the cab 4 extends over almost the entire surface from the vicinity of the upper end to the vicinity of the lower end on the front side. The illustrated front window 8 has an upper portion projecting forward and is inclined obliquely inward as it goes downward.

  The hydraulic excavator performs operations such as excavation of earth and sand, and operates under conditions where a large amount of dust is generated during excavation of the earth and sand and depending on the surrounding environmental conditions. For this reason, dirt, such as dust, may adhere to the surface of the front window 8, that is, the outer surface. If a large amount of fouling matter adheres to the front window 8, the operator's field of view is obstructed, and the smoothness and safety of operations such as excavation of earth and sand are impaired, resulting in a reduction in work efficiency. In addition, since the outside must be seen from the stained front window 8, a great burden is imposed on the eyes of the operator, and the feeling of fatigue becomes intense. For this reason, it is necessary to keep the front window 8 in a clean state at least during the operation of the hydraulic excavator so as to prevent adhesion of pollutants such as sand dust.

  In the present invention, in order to clean the front window 8 so that dirt such as dust does not adhere, the air curtain is made to flow along the outer surface of the front window 8 from the upper end side toward the lower end side. Try to form. Thus, by forming a laminar air flow from the upper side of the front window 8, even if dirt such as dust is scattered or floating near the front window 8, it is attached to the front window 8. Instead of being attached, it is transported to the downward flow by this downflow, and is prevented from adhering to the surface of the front window 8 and is always in a cleaned state. That is, as is clear from FIGS. 3 and 4, an air outlet 9 having a length close to the entire length in the width direction of the front window 8 is installed from the upper position of the front window 8 of the cab 4. An air curtain composed of a down flow along the outer surface is formed from the air jet port 9.

  Next, the air flow source supplied to the air jet port 9 will be described. Various heat exchangers are installed inside the building 5 in the upper swing body 2. A typical heat exchanger includes a radiator 10 and an oil cooler 11. The radiator 10 and the oil cooler 11 exchange heat with the fluid to be cooled that circulates in the heat exchanging section by circulating cooling air supplied from a cooling fan to the heat exchanging section. In addition to these, for example, an intercooler or the like may be installed as the type of heat exchanger.

  In the structure of the hydraulic excavator shown in FIG. 2, the radiator 10 and the oil cooler 11 are installed at different positions and cooled by independent cooling fans 12 and 13, respectively. However, the radiator 10 and the oil cooler 11 may be arranged in series or in parallel and cooled by a single cooling fan. The cooling fan 13 for the oil cooler 11 is rotationally driven by a hydraulic motor, and the cooling fan 12 for the radiator 10 is directly connected to the engine 6. The cooling fans 12 and 13 suck cooling air and suck outside air to cool the radiator 10 and the oil cooler 11.

  As shown by arrows in FIGS. 1 and 2, in the flow of air in which outside air is taken in and the radiator 8 is cooled by the cooling fan 12 directly connected to the engine 6, the exhaust on the downstream side of the cooling fan 10 also has a predetermined flow velocity. have. This exhaust gas is used as an air flow for an air curtain supplied to the air jet port 9. For this purpose, inside the building 5, a cooling fan 12 connected to an engine 6 (of the two engines 6, the engine 6 located on the right side in which the cab 4 is disposed in front in FIG. 2). On the downstream side, that is, in the air flow after the cooling of the radiator 10, a duct 14 having an intake port portion 14a is provided at a portion where the exhaust is at a high speed. The duct 14 extends from the upper part of the building 5 through the passage part of the upper revolving structure 2 to the roof 16 from the rear wall 15 of the cab 4, and is disposed at the upper position of the front window 8 in the roof 16. Connected to the air outlet 9.

  By forming a downflow flow in a laminar flow so that the air ejected from the air ejection port 9 is in close contact with the outer surface of the front window 8, a cleaning air curtain in the front window 8 is formed. For this purpose, as shown in FIG. 5, a grill 17 comprising a plurality of wind direction plates 17 a is attached to the air outlet 9, and the air flow descending in the air outlet 9 is directed toward the front window 8. The incident direction is changed at a shallow angle. Here, the wind direction plate 17a of the grill 17 may be fixed, but it is desirable that the angle can be adjusted in order to accurately form the air curtain.

  Further, in the middle of the duct 14, for example, a state in which the air flow supplied from the cooling fan 12 is supplied to the air ejection unit 9 in a portion located in the passage of the upper swing body 2, and a state in which the air is discharged to the outside air. Opening / closing means 18 for switching to is provided. The opening / closing means 18 has a box portion 19, and the duct portion 14 is divided into two by an upstream side 14 </ b> U and a downstream side 14 </ b> D. An opening 19 a is formed in the upper surface of the box portion 19, and the opening 19 a can be opened and closed by an opening / closing lid 20, and the opening / closing lid 20 is connected to the box portion 19 by a hinge 21. Normally, the opening / closing lid 20 is held in a closed state (solid line state in FIG. 6) by the stopper 22, and the upstream side 14U and the downstream side 14D of the duct 14 communicate with each other. The stopper 22 is fixed to the shaft 23a of the handle 23. By rotating the handle 23 about the axis of the shaft 23a, the locking of the opening / closing lid 20 by the stopper 22 is released, and the hinge 21 is moved. As a center, it rotates downward in the figure. As a result, the downstream side 14D of the duct 14 is covered with the opening / closing lid 20 and the opening 19a is opened as shown by the phantom line in FIG. 6, and the upstream side 14U of the duct 14 is connected to the downstream side 14D. Is disconnected, and the air is exhausted from the opening 19a to the outside air. In the figure, 24 is a handle.

  The present embodiment is configured as described above. When the hydraulic excavator is started, the engine 6 is driven, the hydraulic pump 7 pressurizes the hydraulic oil, and the hydraulic actuator includes a hydraulic cylinder and a hydraulic motor. The pressure oil is supplied to each part, and each part operates. Therefore, the engine 6 is always driven while the hydraulic excavator is in operation. And the radiator 10 which makes engine cooling water a to-be-cooled fluid operates continuously, and the cooling air by the cooling fan 12 circulates. Since the intake port portion 14a of the duct 14 is opened at a position downstream of the cooling fan 12 in the flow path of the cooling air supplied to the radiator 10 by the cooling fan 12, the exhaust gas passing through the radiator 10 is taken in by this intake. The air is taken into the duct 14 from the mouth portion 14a. Since this duct 14 extends to the roof 16 of the cab 4 and is connected to the air outlet 9, the air flowing in the duct 14 is supplied to the air outlet 9.

  Since the entire length of the air outlet 9 extends to substantially the entire length in the width direction of the front window 8, air having a predetermined flow velocity flows out from the upper position of the front window 8 from the air outlet 9. . A grill 17 is provided at the air outlet 9, and the air supplied from the duct 14 comes into contact with the front window 8 at a shallow angle by the wind direction action of the grill 17. The front window 8 has a flat surface and is inclined in the incident angle direction of the air supplied through the grill 17. Accordingly, the air ejected from the air ejection port 9 flows down in a laminar flow state along the outer surface of the front window 8, so that a protective film called an air curtain is always formed on the outer surface of the front window 8. Since this protective film is in a downflow, even if contaminants such as dust that scatters and floats around the front window 8 approach the front window 8, it is transported to this downflow and adheres to the front window 8. This prevents the front window 8 from performing a cleaning function.

  As described above, during operation of the hydraulic excavator, a cleaning air curtain is always formed on the front window 8, and this air curtain is included in the exhaust after cooling the radiator 10 by the cooling fan 12. In this case, energy such as an air compressor is utilized, and an apparatus such as an air compressor is not provided to form an air curtain. Therefore, no additional energy is consumed. In terms of configuration, the duct 14 is merely routed around, which is inexpensive and advantageous in terms of maintenance.

  While the hydraulic excavator is in operation, an air curtain is always formed. However, since the air pressure source is exhaust gas after exchanging heat with the radiator 10, the temperature is generally higher than the outside air temperature. Therefore, when there is no possibility of contaminated materials adhering to the front window 8 such as when operating in a situation where dust or the like does not occur, the front window 8 is heated when the air curtain flows along the front window 8. In addition, the air may fluctuate and the operator may feel somewhat uncomfortable when looking at the front window 8 from inside the cab 4. In such a case, the opening / closing door 20 can open the opening 19a of the box portion 19 of the opening / closing means 18, and the downstream side 14D of the duct 14 can be closed. As a result, air is not supplied to the air outlet 9 and is released to the outside air from the opening 19a. As a result, the exhaust does not stay on the downstream side of the cooling fan 12, and there is no inconvenience such as a decrease in the cooling efficiency of the radiator 10.

  As described above, since the temperature of the air supplied from the duct 14 to the air outlet 9 is increased by heat exchange with the radiator 10, condensation occurs on the glass of the front window 8 in winter or cold districts. If so, it can be thawed quickly by flowing air with this heat. In addition, if a large temperature difference occurs between the inside and outside of the front window 8 by cooling the inside of the cab 4, the outside air contacting the front window 8 is cooled, and condensation may occur on the glass. . In such a case, supplying air with heat to the outer surface of the front window 8 can prevent the front window 8 from being excessively cooled, thereby suppressing the occurrence of condensation.

It is a configuration explanatory view showing a configuration in which the window cleaning device of the present invention is provided in the cab of a hydraulic excavator as an example of a construction machine. It is a top view of FIG. 1 which abbreviate | omits excavation operation means. It is a principal part enlarged view of FIG. 1 which shows the site | part of the front window in cross section. It is a front view of a driver's cab. It is composition explanatory drawing of an air jet nozzle. It is composition explanatory drawing of an opening-closing means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper turning body 3 Excavation work means 4 Driver's cab 5 Building 6 Engine 8 Front window 9 Air outlet 10 Radiator 12 Cooling fan 14 Duct 14a Intake port 17 Grill 18 Opening / closing means

Claims (3)

In an apparatus for cleaning a driver's cab window that forms an air curtain along the outer surface of a window glass attached to a driver's cab of a construction machine,
A duct having one end opened on the downstream side of the cooling fan that circulates the cooling air to the heat exchanger of the construction machine is routed to the upper position of the window,
A window cleaning device for a cab of a construction machine, characterized in that an air ejection portion having a predetermined length in the width direction of the window is connected to the other end of the duct. 2. The cab of a construction machine according to claim 1, wherein the window in which the air curtain is formed is a front window, and the air ejection portion is configured to open to cover the entire width of the front window. Window cleaning device. 2. The duct includes an opening / closing means for switching between a state in which a flow of air supplied from the cooling fan is supplied to the air ejection part and a state in which the air is discharged to the outside air. Window cleaning equipment in the cab of construction machinery.

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