Work equipment

Abstract

To prevent a cushioning material arranged on a connection part of ducts from being peeled when the ducts are attached or detached in a working machine having a duct structure with a plurality of ducts connected.SOLUTION: A working machine includes a machine body, a cabin mounted on the machine body, an air conditioner main body which generates air-conditioned air supplied in the cabin, and a duct structure which guides the air-conditioned air supplied from the air conditioner main body. The duct structure includes one duct and the other duct which are mutually connected. The one duct has a first connection part which is inserted and connected to the other duct. The other duct has a second connection part to which the one duct is inserted and connected. The first connection part has a first end surface orthogonal to an insertion direction. The second connection part has a second end surface opposite to the first end surface. A cushioning material is interposed between the first end surface and the second end surface.SELECTED DRAWING: Figure 30

Description

[Technical Field]

[0001] The present invention relates to a work machine such as a backhoe. [Background technology]

[0002] BACKGROUND ART A working machine disclosed in Patent Document 1 is known in the prior art. The work machine disclosed in Patent Document 1 is equipped with a duct that guides conditioned air from an air conditioner main body and sends it into the cabin. This duct is formed by connecting multiple ducts. Cushioning material is provided at the connections between the ducts (see Figures 49 to 53). The cushioning material is fixed so as to surround the end connection ports of the ducts. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-116176 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of the above-disclosed technology, when one duct is inserted into another duct to connect them, or when one duct is removed from the other duct, the inner surface of the duct rubs against the outer surface of the cushioning material, which may cause the cushioning material to peel off. The present invention has been made in consideration of the above-mentioned problems, and its purpose is to prevent cushioning material provided at the connection between ducts from peeling off when the ducts are attached or detached in a work machine having a duct structure in which multiple ducts are connected. [Means for solving the problem]

[0005] A work machine according to one aspect of the present invention includes a body, a cabin mounted on the body, an air conditioner main body that generates conditioned air to be supplied to the interior of the cabin, and a duct structure that guides the conditioned air supplied from the air conditioner main body, wherein the duct structure includes one duct and another duct that are connected to each other, the one duct has a first connection portion that is inserted into and connected to the other duct, the other duct has a second connection portion that the one duct is inserted into and connected to, the first connection portion has a first end face that is perpendicular to an insertion direction, the second connection portion has a second end face that faces the first end face, and a cushioning material is interposed between the first end face and the second end face. the first end surface is an annular surface extending inward from an outer peripheral surface of one of the ducts, the second end surface is an annular surface extending inward from an outer peripheral surface of the other duct, the cushion material is an annular member abutting the first end surface and the second end surface, the second connection portion has a folded portion folded back from an inner end of the second end surface toward an opposite side to the first end surface, and the inward extension length of the second end surface from the outer peripheral surface is The first connecting portion has a length longer than the length in the insertion direction, and has a cylindrical portion extending from the inner end of the first end face toward the other duct, and a protrusion to which the folded portion is engaged is formed on the outer surface of the cylindrical portion, and the protrusion protrudes in an arc shape from the outer surface of the cylindrical portion, and a recess that is recessed toward the outer surface at a position corresponding to the protrusion is formed on the inner surface of the cylindrical portion, and the protrusion is integrally connected to the first end face, and the folded portion is integrally connected to the second end face. . [Effects of the Invention]

[0006] According to the above configuration, the cushioning material is interposed between the first end face perpendicular to the insertion direction and the second end face opposite the first end face, so that when the ducts are attached or detached, the inner surface of the duct does not rub against the outer surface of the cushioning material, and therefore peeling off of the cushioning material can be prevented when the ducts are attached or detached. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic side view showing the overall configuration of a work machine. [Figure 2] FIG. 2 is a schematic plan view of the work machine. [Figure 3] FIG. 2 is a schematic plan view showing the interior of the cabin. [Figure 4] FIG. 2 is a schematic side view showing the interior of the cabin. [Figure 5] This is a perspective view of the cabin and aircraft body as seen from the rear right. [Figure 6] This is an oblique view of the cabin and aircraft body from the rear left. [Figure 7] FIG. 2 is a rear view of the cabin and fuselage. [Figure 8] FIG. 2 is a plan cross-sectional view of the air conditioner body and duct structure. [Figure 9]FIG. 2 is a partial cross-sectional side view of the outside air duct, the inside / outside air switching device, and the air conditioner main body. [Figure 10] This is a plan view of the driver's seat, duct structure, air conditioner main body, outside air duct, inside / outside air switching device, etc. [Figure 11] This is a perspective view of the right steering device, duct structure, etc., seen from the front left. [Figure 12] FIG. [Figure 13] FIG. 2 is an exploded perspective view of the duct structure. [Figure 14] FIG. 2 is a plan cross-sectional view showing the connection between the switching box and the relay duct, the first duct, and the second duct. [Figure 15] This is an oblique view of the right flight control device, the cabin interior wall, the first duct, etc., seen from the front left. [Figure 16] FIG. 10 is a perspective view showing the right steering device, the duct structure, and the cover member. [Figure 17] FIG. 2 is a perspective view of the rear of the cabin and the outside air duct as viewed from the left rear. [Figure 18] FIG. 2 is a perspective view showing a state in which a rear cover is removed from the rear of the cabin. [Figure 19] FIG. 2 is a perspective view of an outside air duct, a first filter, a second filter, and a frame. [Figure 20] FIG. 2 is a perspective view of the rear cover as seen from the front. [Figure 21] FIG. 10 is a rear view showing the state in which the lid body is removed from the rear cover. [Figure 22] FIG. [Figure 23] FIG. 10 is a perspective view showing a state in which a net body is housed in a case attached to a lid body. [Figure 24] FIG. 10 is a perspective view showing a state in which the net body is being removed from the case attached to the lid body. [Figure 25] FIG. 2 is a perspective view of the case as seen from the front. [Figure 26] FIG. 2 is a vertical cross-sectional view of the rear cover, the lid body, the mesh body, and the case. [Figure 27] FIG. 2 is a plan view showing the state in which the lid is closed. [Figure 28] FIG. 2 is a plan view showing a state in which the lid is open. [Figure 29] FIG. 2 is a perspective view showing a first connection portion of one duct (first duct) and a second connection portion of the other duct (third duct). [Figure 30] FIG. 3 is a cross-sectional view showing a state in which one duct (first duct) and the other duct (third duct) are connected. [Figure 31] 10A and 10B are cross-sectional views illustrating a manufacturing method of the other duct. [Figure 32] FIG. 10 is a cross-sectional view showing a state in which one duct (second duct) and the other duct (fourth duct) are connected. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate. Fig. 1 is a schematic side view showing the overall configuration of a work machine 1 according to this embodiment. Fig. 2 is a schematic plan view of the work machine 1. In this embodiment, a backhoe, which is a swivel work machine, is exemplified as the work machine 1. 1 and 2, the work machine 1 includes a machine body (swivel base) 2, a traveling device 3, and a work device 4. Note that the work device 4 is omitted in FIG.

[0009] A cabin 5 is mounted on the machine body 2. A driver's seat 6 where an operator (driver) sits is provided inside (inside) the cabin 5. In other words, the driver's seat 6 is surrounded by the cabin 5. The driver's seat 6 has a seat portion 6A where the operator sits and a backrest portion 6B where the operator's back is supported. In this embodiment, the direction toward the front of an operator seated in the driver's seat 6 of the work machine 1 (the direction of arrow A1 in FIGS. 1 and 2) will be referred to as the forward direction, the direction toward the rear of the operator (the direction of arrow A2 in FIGS. 1 and 2) will be referred to as the rearward direction, and the direction of arrow K1 in FIGS. 1 and 2 will be referred to as the longitudinal direction. Furthermore, the direction toward the left side of the operator (the near side in FIG. 1, the direction of arrow B1 in FIG. 2) will be referred to as the left side, and the direction toward the right side of the operator (the far side in FIG. 1, the direction of arrow B2 in FIG. 2) will be referred to as the right side. Furthermore, the horizontal direction, which is perpendicular to the longitudinal direction K1, will be referred to as the machine body width direction K2 (see FIG. 2).

[0010] As shown in Figures 1 and 2, the traveling device 3 is a crawler-type traveling device that supports the machine body 2 so that it can travel. The traveling device 3 has a traveling frame 3A, a first traveling device 3L provided on the left side of the traveling frame 3A, and a second traveling device 3R provided on the right side of the traveling frame 3A. The first traveling device 3L and the second traveling device 3R are driven by a traveling motor M1 configured by a hydraulic motor (hydraulic actuator). In this embodiment, a crawler-type traveling device 3 is used, but this is not limiting, and a wheel-type traveling device or the like may also be used. A dozer device 7 is attached to the front of the traveling device 3 (see Figure 1).

[0011] As shown in Fig. 1, the machine body 2 is supported on the traveling device 3 via a swivel bearing 8 so as to be rotatable about a swivel axis X1, which is an axis extending in the vertical direction. As shown in Fig. 2, a cabin 5 is mounted on the machine body 2 toward the left and front. As shown in Fig. 1, the machine body 2 has, at its front, a support bracket 9 and a swing bracket 10 that support the working device 4. The support bracket 9 is provided so as to protrude forward from the machine body 2. The swing bracket 10 is attached to the front of the support bracket 9 so as to be swingable around a vertical axis (an axis extending in the up-down direction).

[0012] As shown in Fig. 1, the work device 4 has a boom 11, an arm 12, and a bucket 13. The base of the boom 11 is pivotally attached to the upper part of the swing bracket 10 so as to be rotatable about a horizontal axis (an axis extending in the width direction K2 of the machine body). The arm 12 is pivotally attached to the tip side of the boom 11 so as to be rotatable about the horizontal axis. The bucket 13 is provided on the tip side of the arm 12 so as to be capable of scooping and dumping operations.

[0013] The work implement 1 can be equipped with other work tools (hydraulic attachments) that can be driven by a hydraulic actuator, instead of or in addition to the bucket 13. Examples of other work tools include a hydraulic breaker, a hydraulic crusher, an angle broom, an earth auger, a pallet fork, a sweeper, a mower, and a snow blower. The swing bracket 10 is capable of swinging by extension and retraction of the swing cylinder C1. The boom 11 is capable of swinging by extension and retraction of the boom cylinder C2. The arm 12 is capable of swinging by extension and retraction of the arm cylinder C3. The bucket 13 is capable of scooping and dumping by extension and retraction of the bucket cylinder C4. The swing cylinder C1, boom cylinder C2, arm cylinder C3, and bucket cylinder C4 are configured as hydraulic cylinders (hydraulic actuators).

[0014] Next, with reference to FIG. 2 and other figures, the layout and configuration of the main devices mounted on the work machine 1 will be described in outline. As shown in Figures 1 and 2, a prime mover E1 is mounted on the rear of the aircraft body 2. The prime mover E1 is a diesel engine. The prime mover E1 may be a gasoline engine or an electric motor, or may be a hybrid type having an engine and an electric motor. A cooling fan 14 is attached to the right of the prime mover E1. The cooling fan 14 is driven by the prime mover E1 and generates cooling air that flows from right to left, that is, from outside the aircraft body 2 toward the prime mover E1.

[0015] To the right of the cooling fan 14 are arranged a radiator 15, an oil cooler 16, and a fuel cooler 17. The radiator 15 is a cooler that cools the coolant that cools the prime mover E1. The oil cooler 16 is a cooler that cools the return hydraulic oil from hydraulic actuators such as hydraulic cylinders and hydraulic motors. The fuel cooler 17 is a cooler that cools the fuel. These coolers are cooled by the cooling air drawn in by the cooling fan 14.

[0016] A compressor 18 driven by the prime mover E1 is disposed in front of the right part of the prime mover E1. The compressor 18 is a device that constitutes part of the air conditioning system (air conditioner) equipped to the work machine 1, and compresses the refrigerant (air conditioning gas) into a semi-liquid state. A fuel tank 19 is disposed in front of the compressor 18, the radiator 15, and the oil cooler 16. The fuel tank 19 is a tank that stores fuel for the prime mover E1. A battery 22 is disposed in front of the fuel tank 19. The battery 22 is a storage battery that supplies power to electrical components equipped on the work machine 1.

[0017] A condenser 23 and a receiver 24, which constitute part of the air conditioning system, are arranged in front of the battery 22. The condenser 23 is a device that dissipates heat from the refrigerant from the compressor 18 to liquefy it. More specifically, it is a cooler that cools the refrigerant that has been semi-liquidized by the compressor 18 to promote liquefaction. In this embodiment, the condenser 23 is an electric condenser that is cooled by an electric fan. The receiver 24 is a device that stores the refrigerant liquefied by the condenser 23, separates the refrigerant that was not liquefied by the condenser 23 from the liquefied refrigerant, and removes moisture and impurities.

[0018] A hydraulic pump 25 is attached to one side (left side) of the prime mover E1. The hydraulic pump 25 is driven by the power of the prime mover E1. The hydraulic pump 25 discharges hydraulic oil (pressurized oil) and the like that drives hydraulic actuators such as hydraulic motors and hydraulic cylinders equipped in the work machine 1. A hydraulic oil tank 28 is disposed to the left of the prime mover E1. The hydraulic oil tank 28 is a tank that stores hydraulic oil. The hydraulic oil tank 28 is disposed below the driver's seat 6. Hydraulic oil is delivered from the hydraulic oil tank 28 to the hydraulic pump 25.

[0019] A control valve V1 is disposed in front of the hydraulic oil tank 28. The control valve V1 controls the flow rate of hydraulic oil supplied from the hydraulic pump 25 to hydraulic actuators that are equipped in the work machine 1 and driven by the hydraulic oil. More specifically, the control valve V1 is a valve unit that aggregates the control valves that control the flow rate of hydraulic oil supplied to the hydraulic actuators that are equipped in the work machine 1.

[0020] 2 and 3, a left steering device 20 and a right steering device 21 are disposed on either side of the driver's seat 6. The left steering device 20 is disposed to the left of the driver's seat 6. The right steering device 21 is disposed to the right of the driver's seat 6. The right operation device 21 has a right operation lever 26 and a dozer operation lever 27. The control valves for the boom cylinder C2 and the bucket cylinder C4 can be controlled by operating the right operation lever 26. The control valves for the dozer cylinder C4 can be controlled by operating the dozer operation lever 27.

[0021] The right control device 21 is a control device that outputs an electric signal in response to operation of the right control lever 26 or the dozer control lever 27. The right control lever 26 is a joystick-type lever that can swing back and forth and left and right. The dozer control lever 27 is a lever that can swing back and forth. The right control device 21 is equipped with a first detection device 32 (see FIG. 11) that detects the amount and direction of operation of the right control lever 26, and a second detection device (not shown) that detects the amount and direction of operation of the dozer control lever 27. The first detection device 32 outputs an electric signal that controls the control valves (solenoid valves) for the boom cylinder C2 and the bucket cylinder C4 in response to the amount and direction of operation of the right control lever 26. The second detection device outputs an electric signal that controls the control valves (solenoid valves) for the dozer cylinder in response to the amount and direction of operation of the dozer control lever 27.

[0022] The left steering device 20 has a left operating lever 30 and an unloading lever 31. By operating the left operating lever 30, it is possible to control a control valve for swing and arm operation. By operating the unloading lever 31, it is possible to switch the hydraulic actuator of the work machine 1 between an operable state and an inoperable state. As shown in Figures 3 and 4, a display device 33 is provided to the right front of the driver's seat 6. The display device 33 has a panel (meter panel) such as a liquid crystal panel. The panel displays items such as an image of the surroundings of the work machine, the operating status, mode changes, various settings, and warnings. The panel also displays information necessary for machine settings, such as remaining fuel, time (clock), height control settings, AI (auto idle) control settings, and arm limit settings, as information related to the work machine. However, the display items displayed on the display device 33 described above are merely examples and are not limiting.

[0023] As shown in Figures 2, 5, and 6, the machine body 2 has a cover device 43. The cover device 43 covers the equipment, parts, members, etc. mounted on a swivel base disposed under the machine body 2. The cover device 43 is configured to have a plurality of covers. The plurality of covers include a first cover 43A to an eighth cover 43H. Each cover is removable or can be opened and closed. The first cover 43A is disposed at the front right of the fuselage 2 and covers the condenser 23 and the receiver 24. The second cover 43B is disposed behind the first cover 43A and covers the upper parts of the fuel tank 19 and the battery 22. The third cover 43C covers the right side of the fuel tank 19 and the battery 22. The fourth cover 43D covers the upper parts of the radiator 15, oil cooler 16, and fuel cooler 17 and the parts extending from the right side to the rear. The fourth cover 43D has an opening 44 for taking in outside air when the cooling fan 14 is driven.

[0024] The fifth cover 43E covers the cooling fan 14 and the radiator 15 from above. The sixth cover 43F covers the rear of the prime mover E1. A weight 35 is provided below the sixth cover 43F. The seventh cover 43G covers the left side of the upper part of the hydraulic oil tank 28. The eighth cover 43H is disposed below the seventh cover 43G and covers the left side of the lower part of the hydraulic oil tank 28.

[0025] As shown in Figures 1 and 2, an air conditioner main body 29 is disposed above the prime mover E1 and the hydraulic pump 25. As shown in Figure 1, the air conditioner main body 29 is disposed above the prime mover compartment (engine compartment) E2 that houses the prime mover E1. The air conditioner main body 29 is also disposed behind the driver's seat 6. Conventionally, the air conditioner main body 29 was disposed below the driver's seat 6, but by disposing the air conditioner main body 29 above the prime mover compartment E2 and behind the driver's seat 6, it is possible to increase the space under the operator's feet.

[0026] The air conditioner main body 29 is a device that constitutes the main body of the air conditioning system. The air conditioner main body 29 generates conditioned air (temperature-adjusted air) to be supplied to the inside of the cabin 5. 5, 6, and 7, an outside air inlet 34 is provided on the rear side of the cabin 5 to take in outside air to be introduced into the air conditioner main body 29. The air conditioner main body 29 takes in air (outside air) introduced from the outside air inlet 34 or air (inside air) inside the cabin 5, and generates temperature-adjusted air (conditioned air) from the taken-in air.

[0027] As shown in Fig. 8, air conditioner main body 29 has housing 29A, and evaporator 29B, heater core 29C, blower fan 29D, etc., which are arranged inside housing 29A. Housing 29A is provided with intake port 29A1 and exhaust port 29A2. Intake port 29A1 is provided at the top of housing 29A (above blower fan 29D) (see Fig. 9). Exhaust port 29A2 is provided at the right side of housing 29A. Wind generated by driving blower fan 29D is taken into housing 29A through intake port 29A1 and discharged to the outside of housing 29A through exhaust port 29A2.

[0028] In the air conditioning system including the air conditioner main body 29, refrigerant from the receiver 24 is injected through an expansion valve into the evaporator 29B and vaporized. The vaporized refrigerant cools the evaporator 29B, and cool air is generated by passing air from the blower fan 29D through the evaporator 29B. The refrigerant leaving the evaporator 29B returns to the compressor 18. The heating system of the air conditioning system uses heat from the prime mover E1. Specifically, high-temperature water heated by the heat of the prime mover E1 is used as a heat medium to warm the heater core 29C, and warm air is generated by passing air from the blower fan 29D through the heater core 29C.

[0029] Air conditioner main body 29 uses an air mix system that mixes cold air and hot air to generate conditioned air for cooling or heating. A first air mix door 29E and a second air mix door 29F are provided inside housing 29A of air conditioner main body 29. First air mix door 29E can swing around first swing shaft 29G. Second air mix door 29F can swing around second swing shaft 29H.

[0030] When the first air mix door 29E and the second air mix door 29F are both in the positions indicated by the solid lines (first state), the air flow of the blower fan 29D becomes a first flow F1 that passes through the evaporator 29B but does not pass through the heater core 29C. The first flow F1 is cooled as it passes through the evaporator 29B, but does not pass through the heater core 29C, so it becomes cool air.

[0031] When the first air mix door 29E and the second air mix door 29F are both in the positions indicated by the imaginary lines (second state), the air flow of the blower fan 29D becomes a second flow F2 that passes through the evaporator 29B and the heater core 29C. After passing through the evaporator 29B, the second flow F2 passes through the heater core 29C and is heated, becoming hot air. When the first air mix door 29E is in the position indicated by the solid line and the second air mix door 29F is in the position indicated by the imaginary line (third state), the air from the blower fan 29D becomes both the first flow F1 and the second flow F2. As described above, the first flow F1 is cool air, and the second flow F2 is warm air.

[0032] The air conditioner main body 29 generates conditioned air for cooling or heating using cold air (first flow) generated by passing through the evaporator 29B and warm air (second flow) generated by passing through the evaporator 29B and the heater core 29C. In the third state, the temperature of the conditioned air generated by the air conditioner main body 29 can be adjusted by adjusting the angle of the air mix doors (first air mix door 29E, second air mix door 29F) to change the ratio between the amount of air in the first flow F1 and the amount of air in the second flow F2. Increasing the amount of air in the first flow F1 and decreasing the amount of air in the second flow F2 decreases the temperature of the conditioned air generated by the air conditioner main body 29. Decreasing the amount of air in the first flow F1 and increasing the amount of air in the second flow F2 increases the temperature of the conditioned air generated by the air conditioner main body 29. This allows the air conditioner main body 29 to generate conditioned air for cooling (air whose temperature is adjusted for cooling) and conditioned air for heating (air whose temperature is adjusted for heating). Hereinafter, air whose temperature is adjusted for cooling will be referred to as "conditioned cool air" and air whose temperature is adjusted for heating will be referred to as "conditioned warm air."

[0033] As shown in FIG. 8, air of a first flow F1 (cold air generated by passing through the evaporator 29B) and air of a second flow F2 (hot air generated by passing through the evaporator 29B and the heater core 29C) are taken out from the exhaust port 29A2 of the housing 29A. The exhaust port 29A2 opens facing one side in the width direction of the airframe (to the right). The air of the first flow F1 (cold air generated by passing through the evaporator 29B) is taken out from the rear of the exhaust port 29A2. The air of the second flow F2 (hot air generated by passing through the evaporator 29B and the heater core 29C) is taken out from the front of the exhaust port 29A2. In other words, the cold air and hot air taken out from the exhaust port 29A2 are taken out from offset positions (offset in the front-to-rear direction) on the exhaust port 29A2. Therefore, the conditioned air taken out from the air conditioner main body 29 is in a state in which the cold air and the hot air are not sufficiently mixed together at the time of taking out.

[0034] As shown in Figures 8, 10, etc., a duct structure 50 is connected to the air conditioner main body 29. The duct structure 50 guides the conditioned air supplied from the air conditioner main body 29. The duct structure 50 is connected to an exhaust port 29A2 of a housing 29A of the air conditioner main body 29. The internal space of the duct structure 50 communicates with the exhaust port 29A2. The duct structure 50 forms a passage that guides the conditioned air generated by the air conditioner main body 29 into the cabin 5.

[0035] 3 and 10, the duct structure 50 passes to the side (right side) of the driver's seat 6 and extends from behind the driver's seat 6 to in front of the driver's seat 6. Also, as shown in FIGS. 4 and 11, etc., the duct structure 50 passes below (near the bottom of) the right steering device 21 and extends in the front-to-rear direction. The right steering device 21 is equipped with operating members such as a right operating lever 26 and a dozer operating lever 27, detection devices (first detection device 32, second detection device, etc.) that detect the operation of the operating members and output electric signals, and a mounting plate 36 to which the operating members and detection devices are attached. The duct structure 50 passes below the operating members, detection devices, mounting plate 36, etc. that make up the right steering device 21, and extends in the front-to-rear direction.

[0036] As described above, the right steering device 21 is an electrically controlled steering device that outputs an electric signal in response to operation of the right operation lever 26 or the dozer operation lever 27. Therefore, a hose (pilot hose) for circulating hydraulic oil (pilot oil) used for control by operation of the right operation lever 26 is not connected to the right steering device 21. As a result, no pilot hose is arranged below the right steering device 21. Therefore, a space is formed below the right steering device 21 due to the omission of the pilot hose, and the duct structure 50 can be arranged in this space.

[0037] As shown in Figures 8, 10, 12 and 13, the duct structure 50 has a relay duct 51, a switching box 52, a first duct 53, a second duct 54, a third duct 55 and a fourth duct 56. Relay duct 51 connects air conditioner main body 29 and switching box 52. As shown in Fig. 8, one end 51d of relay duct 51 is connected to exhaust port 29A2 of air conditioner main body 29. The other end 51e of relay duct 51 is connected to switching box 52.

[0038] As shown in Figures 3 and 10, the relay duct 51 is disposed behind the seat portion 6A of the driver's seat 6. One end of the relay duct 51 is located behind the driver's seat 6 in the front-to-rear direction. The other end of the relay duct 51 overlaps with the driver's seat 6 in the front-to-rear direction. More specifically, the other end of the relay duct 51 overlaps with the backrest portion 6B of the driver's seat 6 in the front-to-rear direction.

[0039] Relay duct 51 mixes the cold air and hot air taken out from exhaust port 29A2 of air conditioner main body 29 and leads the mixed air to switching box 52. In other words, relay duct 51 has a length sufficient to mix the cold air and hot air taken out from exhaust port 29A2 of air conditioner main body 29 (a length that allows mixing). As a result, as shown in FIG. 8 , cold air flow F1 and hot air flow F2 become a sufficiently mixed flow F3 while flowing through relay duct 51. Therefore, the air that passes through relay duct 51 and is introduced into switching box 52 becomes conditioned air in which cold air and hot air are sufficiently mixed. In other words, the space inside relay duct 51 functions as an inlet space for sufficiently mixing the cold air and hot air from air conditioner main body 29 to switching box 52.

[0040] As shown in Figures 8 and 10, relay duct 51 curves and extends forward from the portion connected to exhaust port 29A2 of air-conditioner main body 29. As shown in Figures 4 and 12, relay duct 51 is inclined downward as it extends forward. Because relay duct 51 is curved and inclined in this way, cool air and warm air are more likely to mix.

[0041] 8, relay duct 51 has expanded flow path section 51f in which the flow path cross-sectional area expands from the air conditioner main body 29 side toward switching box 52 side. In other words, the flow path cross-sectional area at the other end of relay duct 51 is wider than the flow path cross-sectional area of ​​exhaust port 29A2 of air conditioner main body 29. This causes the flow velocity of air flowing through relay duct 51 to decrease toward switching box 52. This allows cool air and warm air to be mixed more reliably.

[0042] As shown in FIGS. 4, 10, 12, etc., relay duct 51 is provided with upper extension 51a extending upward. Upper extension 51a is provided at the rear of relay duct 51 (near exhaust port 29A2). Lid 51b is provided at the upper end of upper extension 51a. First through-hole 51c is formed in lid 51b. Cup holder 57 (see FIG. 3) capable of holding a beverage container or the like is provided above lid 51b of upper extension 51a. The bottom surface of cup holder 57 is located above lid 51b. Second through-hole 57a is formed in the bottom surface of cup holder 57. A portion of the conditioned air extracted from exhaust port 29A2 of air conditioner main body 29 is guided to upper extension 51a, passes through first through-hole 51c and second through-hole 57a, and is released into cup holder 57. This allows the beverage container held in cup holder 57 to be cooled or heated.

[0043] As shown in Figures 8, 10, and 12, the switching box 52 is connected to the relay duct 51, the first duct 53, and the second duct 54. As shown in Figure 13, the switching box 52 has a rear connection port 52a, a front connection port 52b, and a side connection port 52c. The rear connection port 52a opens toward the rear. The front connection port 52b opens toward the front. The side connection port 52c opens toward the left front. The rear connection port 52a is connected to the relay duct 51. The front connection port 52b is connected to the first duct 53. The side connection port 52c is connected to the second duct 54.

[0044] As shown in Figures 3 and 10, the switching box 52 is disposed to the side (right side) of the driver's seat 6. As shown in Figure 4, part or all of the switching box 52 is located in a position overlapping with the driver's seat 6 in a side view. In addition, the switching box 52 is disposed below the right steering device 21. 8 and 14, switching box 52 has switching unit 52d that can switch between a first state in which switching box 52 communicates with first duct 53 and a second state in which switching box 52 communicates with second duct 54. The first state in which switching box 52 communicates with first duct 53 is a state in which conditioned air supplied from air conditioner main body 29 is circulated through first duct 53. The second state in which switching box 52 communicates with second duct 54 is a state in which conditioned air supplied from air conditioner main body 29 is circulated through second duct 54.

[0045] The switching portion 52d has a swing plate 52f that can swing around a support shaft 52e. The swing plate 52f is configured to be swingable between a first position (position shown by a solid line) where the side connection port 52c is closed and the front connection port 52b is open, and a second position (position shown by a virtual line) where the front connection port 52b is closed and the side connection port 52c is open. When the swing plate 52f is in the first position, the switching box 52 is in a first state in which it is connected to the first duct 53. When the swing plate 52f is in the second position, the switching box 52 is in a second state in which it is connected to the second duct 54. When conditioned cool air is flowing through the relay duct 51, the switching box 52 is in the first state, and the conditioned cool air flows from the front connection port 52b to the first duct 53. When conditioned warm air is flowing through the relay duct 51, the switching box 52 is in the second state, and the conditioned warm air flows from the side connection port 52c to the second duct 54.

[0046] The swing plate 52f is swung by an electric drive mechanism such as an electric motor. The drive mechanism is driven by an operator operating an operation switch (not shown) located near the driver's seat 6. The operation switch is, for example, a switch for switching between a cooling mode and a heating mode. When the operator switches the operation switch to cooling mode, the swing plate 52f is set to the first position, and cool air for cooling flows from the switching box 52 to the first duct 53. At this time, conditioned cool air is generated in the air conditioner main body 29 and supplied to the switching box 52 via the relay duct 51.

[0047] When the operator switches the operation switch to heating mode, the swing plate 52f moves to the second position, and warm air for heating flows from the switching box 52 to the second duct 54. At this time, conditioned warm air is generated in the air conditioner main body 29 and supplied to the switching box 52 via the relay duct 51. The first duct 53 circulates the conditioned cool air extracted from the switching box 52. The first duct 53 connects the switching box 52 and the third duct 55. As shown in FIG. 12 , the first duct 53 is arranged alongside the relay duct 51, the switching box 52, and the second duct 54 in the width direction of the airframe.

[0048] 12 and 13, the first duct 53 has a first section 53a, a second section 53b, and a third section 53c. The first section 53a, the second section 53b, and the third section 53c are configured as an integral body, and their internal spaces are in communication with each other. The first portion 53a is formed in a rectangular cylindrical shape and extends longitudinally in the front-rear direction. The rear end of the first portion 53a is connected to the switching box 52, and the front end is connected to the third duct 55. In other words, the first portion 53a is a connection portion that connects the switching box 52 and the third duct 55, which is disposed in front of the first duct 53. The first portion 53a is inclined downward as it extends forward.

[0049] The second portion 53b is a portion that connects the first portion 53a and the third portion 53c. The second portion 53b extends laterally (to the right) from the side surface (right side surface) of the rear portion of the first portion 53a, and then curves and extends upward. The third section 53c extends upward from the upper end of the second section 53b. The third section 53c is a flat section whose length in the fuselage width direction is shorter than its length in the front-to-rear direction. As shown in FIG. 15 , the third section 53c is disposed between the right controller 21 and the inner wall surface 5a of the cabin 5. The third section 53c extends in the up-down direction between the right controller 21 and the inner wall surface (right wall surface) 5a of the cabin 5 on the side where the right controller 21 is disposed. In other words, the third section (flat section) 53c rises upward from the first section (main body section) 53a along the inner wall surface 5a of the cabin 5. The length of the third section (flat section) 53c in the fuselage width direction is shorter than the length of the first section (main body section) 53a in the fuselage width direction.

[0050] A cutout portion 36a is formed in the right portion (the inner wall surface 5a side) of the mounting plate 36 of the right steering device 21, cut out toward the left (toward the driver's seat 6), and the third portion 53c fits into the cutout portion 36a. As shown in FIGS. 12 and 13, the third portion 53c extends further rearward than the first portion 53a. As shown in FIG. 10, the third portion 53c extends further rearward than the driver's seat 6.

[0051] As shown in Figures 3, 4, 10, 13, 15, etc., the first duct 53 has a first outlet 53d. The first outlet 53d is an outlet that blows out conditioned cool air. The first outlet 53d includes a front outlet 53d1 and a rear outlet 53d2. The front outlet 53d1 is provided in the front upper part of the third section 53c. The rear outlet 53d2 is provided in the rear upper part of the third section 53c.

[0052] As shown in FIGS. 3 and 10, the front air outlet 53d1 is disposed to the side (right side) of the driver's seat 6. Also, as shown in FIG. 4, the front air outlet 53d1 is disposed above the right steering device 21. The front-to-rear position of the front air outlet 53d1 overlaps with the seat portion 6A of the driver's seat 6. More specifically, the front end of the front air outlet 53d1 is located behind the front end of the seat portion 6A, and the rear end of the front air outlet 53d1 is located forward of the rear end of the seat portion 6A. The up-down position (height) of the front air outlet 53d1 overlaps with the backrest portion 6B of the driver's seat 6. As shown in FIG. 12, the front air outlet 53d1 opens toward the upper left.

[0053] The front air outlet 53d1 provided on the right side of the seat portion 5A of the driver's seat 6 blows cool air toward the upper left (above the driver's seat 6 side) (see arrow Y1 in FIGS. 3, 4, and 10). As a result, the cool air is blown toward the face (in front of the face) of the operator OP sitting in the driver's seat 6. By blowing the cool air toward the face of the operator OP in this way, the operator OP can feel a strong sense of coolness.

[0054] As shown in Figures 3 and 4, the rear air outlet 53d2 is disposed rearward of the driver's seat 6. As shown in Figure 3, the rear air outlet 53d2 is disposed to the right of the driver's seat 6. In other words, the rear air outlet 53d2 is disposed to the right rear of the driver's seat 6. Furthermore, as shown in Figure 4, the rear air outlet 53d2 is disposed above the right operating device 21. The vertical position (height) of the rear air outlet 53d2 overlaps with the backrest 6B of the driver's seat 6. The rear air outlet 53d2 opens upward. An air outlet tube 58 is attached to the rear air outlet 53d2. The air outlet tube 58 opens forward and upward.

[0055] The rear air outlet 53d2 provided at the rear right of the seat portion 5A of the driver's seat 6 blows out cool air in a forward and upward direction through the air outlet pipe 58 (see arrow Y2 in FIGS. 3, 4, and 10). As a result, the cool air is blown out toward the back of the head of the operator OP sitting in the driver's seat 6. The second duct 54 is a duct that circulates the conditioned warm air extracted from the switching box 52. The rear end of the second duct 54 is connected to the side connection port 52c of the switching box 52. The front end of the second duct 54 is connected to the fourth duct 56. As shown in FIG. 4, the second duct 54 is inclined downward as it extends forward. The second duct 54 is also located below the right flight control unit 21. As shown in FIGS. 8, 10, and 12, the second duct 54 is located alongside the first portion 53a of the first duct 53 in the aircraft width direction.

[0056] The third duct 55 is a duct that guides the conditioned cool air that has circulated through the first duct 53 further forward. As shown in FIGS. 3, 4, 10, and 12, the third duct 55 extends forward from the front end of the first duct 53, then bends and extends upward (upward and forward). The third duct 55 has a second outlet 55a. The second outlet 55a is an outlet that blows out the conditioned cool air. The second outlet 55a is disposed in front of the driver's seat 6. As shown in FIG. 4, the vertical position (height) of the second outlet 55a overlaps with the seat portion 6A of the driver's seat 6 and is located at a height near the seat surface of the seat portion 6A. The second outlet 55a opens to the left (or rear left) at the right front of the driver's seat 6. The second air outlet 55a blows cool conditioned air toward the front of the legs (near the knees) of the operator OP sitting in the driver's seat 6 (see arrow Y12 in FIGS. 3, 4 and 10).

[0057] The fourth duct 56 is a duct that guides the conditioned warm air that has flowed through the second duct 54 further forward. As shown in FIGS. 3, 4, 10, and 12, the fourth duct 56 extends forward from the front end of the second duct 54, then bends and extends upward. The fourth duct 56 has a third outlet 56a. The third outlet 56a is an outlet that blows out the conditioned warm air. The third outlet 56a is located in front of the driver's seat 6. The third outlet 56a includes a lower outlet 56a1, a side outlet 56a2, and an upper outlet 56a3.

[0058] As shown in Fig. 4, the lower air outlet 56a1 is positioned below the seat portion 6A of the driver's seat 6 in the up-down direction. The lower air outlet 56a1 opens facing downward (lower left). The conditioned warm air blown out from the lower air outlet 56a1 flows toward the feet of the operator sitting in the driver's seat 6 (see arrow Y13 in Fig. 4). As shown in FIG. 4 and other figures, the side air outlet 56a2 is disposed further forward than the second air outlet 55a and the lower air outlet 56a1. The vertical position of the side air outlet 56a2 is lower than the seat surface of the seat portion 5A of the driver's seat 6. The side air outlet 56a2 opens facing the left front. The side air outlet 56a2 is an air outlet for a defroster. Warm air conditioned by the side air outlet 56a2 is blown out toward the left front (see arrow Y14 in FIG. 4). This helps to defog the front window of the cabin 5.

[0059] As shown in FIG. 4 and other figures, the upper air outlet 56a3 is disposed forward of the second air outlet 55a and the lower air outlet 56a1. The upper air outlet 56a3 is positioned higher in the vertical direction than the second air outlet 55a. The upper air outlet 56a3 opens facing the left front. The upper air outlet 56a3 is an air outlet for a defroster. Warm air conditioned by the upper air outlet 56a3 is blown out toward the left front (see arrow Y15 in FIGS. 3, 4, and 10). This helps to defog the front window of the cabin 5.

[0060] As shown in Figures 3, 4, 11, and 15, the work machine 1 is provided with a cover member 60 that covers the duct structure 50. As shown in Figure 16, the cover member 60 includes a first cover member 61, a second cover member 62, a third cover member 63, and a fourth cover member 64. Note that Figure 4 shows only the third cover member 63, and Figure 15 shows only the second cover member 62.

[0061] The first cover member 61 covers the front portion of the duct structure 50. The first cover member 61 covers the periphery of the third duct 55 and the fourth duct 56. As shown in FIG. 11, the first cover member 61 has a first ventilation hole 61a, a second ventilation hole 61b, a third ventilation hole 61c, and a fourth ventilation hole 61d. The first ventilation hole 61a is provided at a position corresponding to the lower outlet 56a1. The second ventilation hole 61b is provided at the side outlet 56a2. The third ventilation hole 61c is provided at a position corresponding to the upper outlet 56a3. The fourth ventilation hole 61d is provided at a position corresponding to the second outlet 55a. A display device 33 is attached to the upper end of the first cover member 61 via a bracket 37 (see FIG. 11, etc.).

[0062] The second cover member 62 covers the left side of the first portion 53a of the first duct 53, the left side of the second duct 54, the left side of the switching box 52, and the left side of the front part of the relay duct 51. The second cover member 62 covers the left side of the portion of the duct structure 50 that is located below the right steering device 21. The third cover member 63 covers the left and upper sides of the second section 53b of the first duct 53. The third cover member 63 covers the portion of the second section 53b that is exposed above the right operating device 21. The third cover member 63 has a fourth air vent 63a at a position corresponding to the front outlet 53d1.

[0063] The fourth cover member 64 covers the left and upper rear part of the relay duct 51 and the upper rear part of the first duct 53. The fourth cover member 64 is disposed behind the right operating device 21. The fourth cover member 64 has a first opening 64a at a position corresponding to the outlet pipe 58, and a second opening 64b at a position corresponding to the cup holder 57. Covering the duct structure 50 with the cover member 60 can prevent damage and deformation of the duct structure 50. Also, temperature changes of the conditioned air circulating inside the duct structure 50 can be suppressed.

[0064] As shown in Figures 9 and 10, the air conditioner main body 29 is connected to an inside / outside air switching device 65. The inside / outside air switching device 65 is connected to an air intake port 29A1 of a housing 29A of the air conditioner main body 29. The inside / outside air switching device 65 is disposed above a blower fan 29D of the air conditioner main body 29. The inside / outside air switching device 65 is disposed behind the driver's seat 6. The inside / outside air switching device 65 switches between a state in which outside air is introduced into the air conditioner main body 29 and a state in which inside air is introduced.

[0065] As shown in FIG. 9 , the inside / outside air switching device 65 has a housing 65a and a switching damper 65b arranged inside the housing 65a. The housing 65a has an inside air intake 65c and an outside air intake 65d. The inside air intake 65c opens facing upward. The outside air intake 65d opens facing rearward. The switching damper 65b can swing around a support shaft 52e as shown by arrow Y3. The switching damper 65b can swing between a first position (position shown by solid lines) where the inside air intake 65c is open and the outside air intake 65d is closed, and a second position (position shown by phantom lines) where the outside air intake 65d is open and the inside air intake 65c is closed. The operation of switching (swinging) the switching damper 65b between the first position and the second position can be performed by a selector switch (not shown) provided near the driver's seat 6.

[0066] When switching damper 65b is in the first position, air inside cabin 5 (inside air) is taken into housing 65a through inside air intake 65c and supplied to air conditioner main body 29. When switching damper 65b is in the second position, air outside cabin 5 (outside air) is taken into housing 65a through outside air intake 65d and supplied to air conditioner main body 29. The air taken in through outside air intake 65d is air introduced from outside air inlet 34 (outside air).

[0067] 9 and 10, an outside air duct 66 is connected to the outside air intake 65d of the inside / outside air switching device 65. The outside air duct 66 is a duct for guiding outside air to the outside air intake 65d. The outside air duct 66 extends in the front-to-rear direction, and its front part is connected to the outside air intake 65d. The outside air duct 66 extends rearward from the outside air intake 65d, and its width (length in the fuselage width direction) increases as it extends rearward.

[0068] As shown in FIG. 17, the outside air duct 66 is attached to an opening 5c ​​provided in the rear surface 5b of the cabin 5. A bulging portion 5d is provided in the rear surface 5b of the cabin 5, bulging rearward to expand the interior space at the rear of the cabin 5, and an opening 5c ​​is formed in this bulging portion 5d. The opening 5c ​​is in communication with the interior space of the cabin 5. The outside air duct 66 has a flange 66a. The bulging portion 5d and the flange 66a are fixed to each other with fasteners such as bolts, thereby fixing the outside air duct 66 to the bulging portion 5d (see FIG. 18). With the outside air duct 66 fixed to the bulging portion 5d, the front portion of the outside air duct 66 is inserted into the cabin 5 through the opening 5c ​​(see FIG. 9).

[0069] 10 and 19, a first filter 71 and a second filter 72 are attached to the outside air duct 66. The first filter 71 and the second filter 72 are attached to the rear part of the outside air duct 66. 19, the first filter 71 has a filter body 71A and a holding portion 71B that holds the filter body 71A. The filter body 71A is disposed in a position that overlaps the second filter 72 in a rear view. The holding portion 71B has an outer peripheral portion 71B1 that is provided around the filter body 71A, and a rear extension portion 71B2 that extends rearward from the outer peripheral portion 71B1. The rear extension portion 71B2 is formed in a rectangular cylindrical shape and is fitted into an opening 66b at the rear of the outside air duct 66.

[0070] The first filter 71 and the second filter 72 are fixed to the rear of the outside air duct 66 by the frame 73. In other words, the frame 73 fixes the second filter 72 and the first filter 71 to the outside air duct 66. The frame 73 fixes the second filter 72 to the outside air duct 66, overlapping the first filter 71. As shown in FIG. 18 , the second filter 72 is exposed from an opening of the frame 73 while being fixed by the frame 73.

[0071] As shown in Figure 19, frame body 73 has a locking portion 73a and a fixing portion 73b. Locking portion 73a is provided on the right side of frame body 73. Locking portion 73a is a portion that is locked to outside air duct 66. A locking hole 66c is provided on the right rear part of outside air duct 66. By inserting locking portion 73a into locking hole 66c, locking portion 73a is locked to locking hole 66c.

[0072] The fixing portion 73b is provided on the left side of the frame 73. The fixing portion 73b is a portion that is fixed to the outside air duct 66. A through hole 73c is provided in the fixing portion 73b. A fixed portion 66d is provided on the left rear side of the outside air duct 66. A screw hole 66e is provided in the fixed portion 66d. The fixing portion 73b is fixed to the fixed portion 66d by aligning the through hole 73c with the screw hole 66e and inserting the knob bolt 74 through the through hole 73c and screwing it into the screw hole 66e.

[0073] With the first filter 71 and the second filter 72 stacked in the front-to-rear direction, the locking portions 73a of the frame body 73 are locked into the locking holes 66c of the outside air duct 66, and the knob bolts 74 are tightened to fix the fixing portions 73b of the frame body 73 to the fixed portions 66d of the outside air duct 66, thereby fixing the frame body 73 together with the first filter 71 and the second filter 72 to the outside air duct 66. When the knob bolts 74 are removed to release the fixation of the fixing portions 73b to the fixed portions 66d, the frame body 73 can be removed from the outside air duct 66, and the first filter 71 and the second filter 72 can be removed.

[0074] As shown in Fig. 10 and other figures, the first filter 71 and the second filter 72 are arranged side by side in the front-to-rear direction. The first filter 71 and the second filter 72 are arranged in a position overlapping with the outside air inlet 34 (see Fig. 7 and other figures) in a rear view. As shown in Figs. 10 and 19, the first filter 71 is attached to the rear of the outside air duct 66. The second filter 72 is arranged between the outside air inlet 34 and the first filter 71 in the front-to-rear direction. In other words, the second filter 72 is arranged in a position closer to the outside air inlet 34 than the first filter 71.

[0075] The first filter 71 and the second filter 72 remove foreign matter contained in the outside air taken in through the outside air inlet 34. Specifically, the second filter 72 first removes foreign matter contained in the outside air taken in through the outside air inlet 34, and then the first filter 71 removes foreign matter contained in the outside air that has passed through the second filter 72. The second filter 72 has a coarser mesh than the first filter 71. In other words, the first filter 71 has a finer mesh than the second filter 72. That is, the first filter 71 is a high-precision filter that can remove finer foreign matter than the second filter 72. By locating the second filter 72 closer to the outside air inlet 34 than the first filter 71, clogging of the finer mesh of the first filter 71 becomes less likely, and the life of the first filter 71 can be extended.

[0076] As shown by arrow Y4 in Figure 10, the outside air taken in through the outside air inlet 34 and passed through the first filter 71 and the second filter 72 is taken into the outside air intake 65d of the inside / outside air switching device 65 by the outside air duct 66 and is led to the air conditioner main body 29. As shown in Figures 1, 2, 5, 6, and 7, a rear cover 77 is attached to the rear surface 5b of the cabin 5, protruding rearward from the rear surface 5b. The outside air inlet 34 is provided in the rear cover 77. The rear cover 77 is located at the bottom of the rear surface 5b of the cabin 5 (below the rear window 5e). The rear cover 77 is detachably attached to the rear surface 5b of the cabin 5.

[0077] As shown in FIG. 20, the rear cover 77 has a first mounting portion 77a, a second mounting portion 77b, and a third mounting portion 77c. A first mounting hole 77d is provided in the first mounting portion 77a. A second mounting hole 77e is provided in the second mounting portion 77b. A third mounting hole 77f is provided in the third mounting portion 77c. As shown in FIG. 18, a first bracket 78, a second bracket 79, and a third bracket 80 are attached to the lower part of the rear surface 5b of the cabin 5. A first mounting hole 78a is provided in the first bracket 78. A second mounting hole 79a is provided in the second bracket 79. A third mounting hole 80a is provided in the third bracket 80. The rear cover 77 is attached to the back surface 5b of the cabin 5 by overlapping the first mounting hole 77d with the first mounting hole 78a, the second mounting hole 77e with the second mounting hole 79a, and the third mounting hole 77f with the third mounting hole 80a, respectively, and fastening them with bolts and nuts.

[0078] As shown in Figures 1, 5, 6, 7, etc., the rear cover 77 is disposed above the sixth cover 43F. As shown in Figure 1, the rear cover 77 is positioned so as to overlap with the driver's seat 6 in the up-down direction. The upper end of the rear cover 77 is positioned lower than the upper end of the driver's seat 6. The lower end of the rear cover 77 is positioned higher than the lower end of the driver's seat 6. As shown in Figure 2, the rear cover 77 is positioned so as to overlap with the driver's seat 6 in the width direction of the vehicle. The right end of the rear cover 77 is positioned to the left of the right end of the driver's seat 6. The left end of the rear cover 77 is positioned to the left of the left end of the driver's seat 6 or at approximately the same position as the left end of the driver's seat 6. The width (length in the width direction of the vehicle) of the rear cover 77 is longer than the width (length in the width direction of the vehicle) of the driver's seat 6.

[0079] The rear cover 77 covers the rear of the air conditioner main body 29 inside the cabin 5. The front of the air conditioner main body 29 is disposed inside the cabin 5. The rear of the air conditioner main body 29 is disposed protruding rearward from the cabin 5. The rear cover 77 covers the rear of the air conditioner main body 29 protruding rearward from the cabin 5. However, the rear of the air conditioner main body 29 does not have to protrude rearward from the cabin 5. In other words, the entire air conditioner main body 29 may be disposed inside the cabin 5 (in front of the rear cover 77). At least the first filter 71, the second filter 72, and the outside air duct 66 are disposed inside the rear cover 77 (see FIG. 10). As shown in Figures 1, 2, 5, 6, 7, and 10, the rear cover 77 has a lid body 81. In a rear view, the lid body 81 has a rectangular shape whose length in the width direction of the machine body is longer than its length in the up-down direction. As shown in Figures 20 and 21, a rear opening 77g is formed in the rear cover 77, and the lid body 81 is attached to cover this rear opening 77g. The lid body 81 can be opened and closed relative to the rear cover 77 (see arrow Y5 in Figure 2). When the lid body 81 is opened, the second filter 72 and the frame body 73 are exposed from the rear opening 77g (see Figure 21). This allows the frame body 73 to be removed from the outside air duct 66 to perform tasks such as replacing the first filter 71 and the second filter 72.

[0080] As shown in Figure 23, a hinge 82 is attached to the right end of the lid 81. This hinge 82 is attached to the right edge of the rear opening 77g of the rear cover 77 (see Figures 20 and 21). This allows the lid 81 to be opened toward the right rear, with the hinge 82 as a fulcrum (see arrow Y5 in Figure 2). A keyhole 81b is provided on the left side of the lid 81. By inserting a key into the keyhole 81b and turning it (locking), the lid 81 can be placed in an unopenable state.

[0081] As shown in FIG. 21, a cushion member 83 is provided near the left edge of the rear opening 77g of the rear cover 77. The cushion member 83 is made of an elastic material such as rubber. The cushion member 83 is disposed in a position facing the rear opening 77g. When the lid body 81 is closed, the cushion member 83 comes into contact with the front surface of the lid body 81 and elastically deforms. This prevents the lid body 81 from rattling when closed.

[0082] As shown in Figures 5, 6, 7, 22, etc., the cover 81 is provided with an outside air inlet 34. The outside air inlet 34 is an opening for taking in air outside the cabin 5 (outside air) into the cabin 5. The outside air is taken in through the outside air inlet 34 by driving the blower fan 29D of the air conditioner main body 29. A plurality of outside air inlets 34 (ten in the illustrated example) are provided. In the present embodiment, the outside air inlets 34 are elongated holes whose length in the width direction of the device is longer than their length in the up-down direction. As shown in FIG. 22 , an area 81R where no outside air inlets 34 are provided is provided in the upper part of the lid 81. In other words, no outside air inlets 34 are provided in the area 81R in the upper part of the lid 81.

[0083] 22, a first rib 84A and a second rib 84B are provided on the front surface of the lid 81. The first rib 84A is provided on the right side of the front surface of the lid 81. The second rib 84B is provided on the left side of the front surface of the lid 81. The first rib 84A and the second rib 84B extend parallel to each other in the vertical direction. As shown in Fig. 23, a case 85 is attached to the front (front face) of the cover 81. As shown in Fig. 24, a mesh 86 is housed in the case 85. The mesh 86 is an insect-catching mesh for capturing insects and the like that enter through the outside air inlet 34. The mesh 86 has a coarser mesh than the second filter 72.

[0084] As shown in FIG. 25 and other figures, the case 85 has a front plate 85a and a peripheral wall 85b. When viewed from the rear, the front plate 85a has a rectangular shape whose length in the width direction of the body is longer than its length in the up-down direction. As shown in FIGS. 23, 24, 25, and other figures, the front plate 85a has openings 85c. A plurality of openings 85c (16 in the illustrated example) are provided. In this embodiment, the openings 85c are elongated holes whose length in the up-down direction is longer than their length in the width direction of the body. The openings 85c allow outside air taken in through the outside air inlet 34 to pass through. A region 85R where no openings 85c are provided is provided in the lower part of the front plate 85a. In other words, no openings 85c are provided in the region 85R at the bottom of the front plate 85a.

[0085] As shown in Figure 22, the front plate 85a is disposed so as to face the outside air inlet 34. A mesh body 86 is disposed behind the front plate 85a. The peripheral wall 85b extends rearward from the outer edge of the front plate 85a. An attachment portion 85d is provided on the peripheral wall 85b. A bolt BL1 is inserted into the attachment portion 85d and screwed into an attachment portion 81a provided on the front surface of the lid body 81, thereby attaching the case 85 to the front part of the lid body 81.

[0086] As shown in Fig. 26, when the case 85 is attached to the front of the lid 81, a space SP1 is formed between the front plate 85a and the lid 81. A mesh body 86 can be housed in this space SP1. When housed in the space SP1, the mesh body 86 is disposed between the first rib 84A and the second rib 84B (see Fig. 23). 26, the net 86 is disposed in the vicinity of the lid 81 so as to face the outside air inlet 34 of the lid 81. Therefore, the net 86 is located closer to the outside air inlet 34 than the second filter 72 (see FIG. 10), which is disposed at a distance from the lid 81. In other words, the net 86 is disposed between the outside air inlet 34 and the second filter 72 while housed in the space SP1. This allows insects and the like that enter through the outside air inlet 34 to be captured by the net 86 before they reach the second filter 72.

[0087] As shown in FIG. 26 , when the case 85 is attached to the front of the lid 81, the opening 85c is located higher than the outside air inlet 34. That is, the height H1 of the lower end of the opening 85c is higher than the height H2 of the upper end of the outside air inlet 34. In other words, the outside air inlet 34 is positioned opposite the area 85R where the opening 85c is not provided. The opening 85c is also positioned opposite the area 81R where the outside air inlet 34 is not provided. As a result, when the work machine 1 is washed with water, wash water that seeps in through the outside air inlet 34 hits the area 85R and flows down, preventing it from entering the opening 85c (see arrow Y6 in FIG. 26 ). The wash water that hits the area 85R and flows down passes through the gap GP2 between the front panel 85a and the mesh body 86 and the gap GP3 between the lid 81 and the rear cover 77 to exit the machine body 2. On the other hand, the outside air taken in through the outside air inlet 34 rises and can enter the opening 85c (see arrow Y7 in FIG. 26).

[0088] As shown in FIG. 25, the peripheral wall 85b of the case 85 extends rearward from the lower, left, and right edges of the outer edge of the front plate 85a. In other words, the peripheral wall 85b is not provided on the upper edge of the front plate 85a. As a result, when the case 85 is attached to the front of the lid body 81, a wide gap GP1 is formed between the case 85 and the lid body 81 at the top of the case 85 (see FIGS. 24 and 26). Therefore, the mesh body 86 can be placed into the case 85 from above the case 85 through this gap GP1 (see arrow Y8 in FIG. 24). The mesh body 86 can also be removed from the case 85 from above the case 85 through this gap GP1. When the mesh body 86 is placed in or removed from the case 85, the first rib 84A and the second rib 84B function as guides to guide the movement of the mesh body 86.

[0089] As shown in Figures 22 and 24, a holding frame 87 that holds the net body 86 is provided around the net body 86. The holding frame 87 is formed in a square ring shape. A fixing portion 87a is provided at the top of the holding frame 87 to fix the holding frame 87 together with the net body 86 to the case 85. The fixing portion 87a extends forward from the top of the holding frame 87 and then bends and extends downward. A through hole 87b is formed in the fixing portion 87a.

[0090] As shown in Figures 22 and 24, a fixed portion 85e is provided on the front surface of the front plate 85a of the case 85. The fixed portion 85e is a portion to which the fixing portion 87a is fixed. The fixed portion 85e protrudes forward from the upper part of the front plate 85a. A screw hole 85f is formed in the fixed portion 85e. With the mesh body 86 housed in the case 85, the holding frame 87 can be fixed to the case 85 by inserting a butterfly bolt 88 into the through hole 87b of the fixing portion 87a and screwing the butterfly bolt 88 into the screw hole 85f of the fixed portion 85e. This positions and fixes the mesh body 86 to the case 85. Furthermore, by removing the butterfly bolt 88 from the screw hole 85f, the holding frame 87 can be released from the case 85. This makes it possible to remove the holding frame 87 together with the mesh body 86 from the case 85.

[0091] 25, the case 85 has a protrusion 85g that protrudes rearward (toward the outside air inlet 34) from the front plate 85a. The protrusion 85g includes a first protrusion 85g1 provided on the left side of the front plate 85a and a second protrusion 85g2 provided on the right side of the front plate 85a. The first protrusion 85g1 and the second protrusion 85g2 extend parallel to each other in the vertical direction. The protrusion length of the protrusion 85g increases from top to bottom.

[0092] As shown in Figure 26, when the case 85 is attached to the front of the lid 81, the protrusion 85g abuts against the front surface of the mesh body 86. As a result, the mesh body 86 is pushed toward the lid 81 by the protrusion 85g and abuts against or comes close to the outside air inlet 34. Here, because the protrusion length of the protrusion 85g increases from top to bottom, the protrusion 85g can be reliably abutted against the front surface of the mesh body 86. Furthermore, because the protrusion length of the protrusion 85g is shorter at the top, the mesh body 86 can be easily placed into the case 85 from above.

[0093] The work machine 1 is provided with a holding portion 90 for holding the lid body 81 in an open state. The holding portion 90 is composed of a holding member 91 (see Figures 20, 21, and 26) provided on the rear cover 77 and a holding mechanism 92 (see Figures 22, 23, 26, etc.) provided on the case 85. As shown in Figures 20 and 21, the holding member 91 is provided on the periphery of the rear opening 77g of the rear cover 77. Specifically, the holding member 91 is provided so as to protrude from the right part of the periphery of the rear opening 77g of the rear cover 77 to the left (towards the rear opening 77g). The holding member 91 is provided between two hinges 82 arranged side by side in the vertical direction. The holding member 91 is flat, with one surface facing upward and the other surface facing downward. A through hole 91a is formed in the holding member 91, penetrating the holding member 91 in the vertical direction.

[0094] As shown in Figures 22 and 23, the holding mechanism 92 is provided on the front surface of the front plate 85a of the case 85. The holding mechanism 92 has a support portion 93, a stay 94, and an engagement portion 95. The support portion 93 protrudes forward from the front surface of the front plate 85a. A through hole 93a extending in the vertical direction is formed in the support portion 93. The support portion 93 supports the stay 94 so that it can rotate around the vertical axis Z1. The stay 94 has a first portion 94a, a second portion 94b, and a third portion 94c. The first portion 94a extends in the vertical direction and is inserted from above into the through hole 93a formed in the support portion 93. The second portion 94b bends from the upper end of the first portion 94a and extends horizontally. The third portion 94c bends from the second portion 94b and extends downward. The third portion 94c The first portion 94a is disposed parallel to the first portion 94a with a gap therebetween.

[0095] The engaging portion 95 is provided on the front surface of the front plate 85a and can engage with the second portion 94b of the stay 94. The engaging portion 95 is formed by bending a springy metal plate. The springiness of the metal plate allows the engaging portion 95 to detachably hold the second portion 94b. The second portion 94b is held by being sandwiched between the metal plates from above and below. The second portion 94b can be engaged with the engaging portion 95 by rotating the stay 94 in one direction about the axis Z1 (the direction of arrow Y9 in FIG. 23). The second portion 94b can be disengaged from the engaging portion 95 by rotating the stay 94 in the other direction about the axis Z1 (the direction of arrow Y10 in FIG. 23). When the second portion 94b is disengaged from the engaging portion 95, the stay 94 can be moved up and down along the through-hole 93a within a predetermined range.

[0096] When the lid 81 is closed, the second portion 94b of the stay 94 is engaged with the engaging portion 95 (see FIGS. 23 and 27). To keep the lid 81 open after opening it, rotate the stay 94 in the other direction around the axis Z1 (the direction of arrow Y10 in FIG. 23 or the direction of arrow Y11 in FIG. 28) to disengage the second portion 94b from the engaging portion 95, and insert the third portion 94c into the through-hole 91a of the holding member 91 from above (see FIG. 28). This restricts the movement of the lid 81 by the stay 94, making it impossible to close the lid 81, and maintaining the lid 81 in an open state. This prevents the lid 81 from closing unintentionally when maintenance (such as replacing a filter) is being performed with the lid 81 open, improving maintainability.

[0097] As described above, the work machine 1 has a filter structure including the mesh body 86, the first filter 71, and the second filter 72 in order to remove foreign matter from the outside air introduced through the outside air inlet 34. The outside air introduced into the rear cover 77 from the outside air inlet 34 passes through the mesh body 86, the second filter 72, and the first filter 71, in that order. This removes foreign matter from the outside air. The outside air from which the foreign matter has been removed is supplied to the air conditioner main body 29 from the inside / outside air switching device 65. The air conditioner main body 29 generates conditioned air, and the generated conditioned air is blown out into the duct structure 50 described above.

[0098] Next, the connection structure of the duct structure 50 will be described. As described above, the duct structure 50 is made up of the relay duct 51, the switching box 52, the first duct 53, the second duct 54, the third duct 55, and the fourth duct 56 (see FIGS. 12 and 13). That is, the duct structure 50 is configured by connecting a plurality of ducts (including the switching box 52). Therefore, the duct structure 50 includes one duct and another duct that are connected to each other.

[0099] Specifically, the duct structure 50 includes a relay duct (one duct) 51 and a switching box (the other duct) 52 that are connected to each other. The duct structure 50 also includes a switching box (one duct) 52 and a first duct (the other duct) 53 that are connected to each other. The duct structure 50 also includes a switching box (one duct) 52 and a second duct (the other duct) 54 that are connected to each other. The duct structure 50 also includes a first duct (one duct) 53 and a third duct (the other duct) 55 that are connected to each other. The duct structure 50 also includes a second duct (one duct) 54 and a fourth duct (the other duct) 56 that are connected to each other.

[0100] 29 and 30 show a case where one duct 50A is the first duct 53 and the other duct 50B is the third duct 55. One duct 50A (first duct 53) has a first connection part 96 that is inserted into and connected to the other duct 50B (third duct 55). The other duct 50B (third duct 55) has a second connection part 97 that is inserted into and connected to the one duct 50A (first duct 53).

[0101] The first connecting portion 96 has a first end surface 96a that is perpendicular to the insertion direction D1 of one duct 50A (first duct 53). The first connecting portion 96 also has a cylindrical portion 96c that extends from an inner end portion 96b of the first end surface 96a toward the other duct 50B (third duct 55). The first end surface 96a is a surface that extends inward (toward the central axis of the duct 50A) from an outer peripheral surface 96d of one duct 50A (first duct 53). The first end surface 96a is a flat surface with an annular (quadratic annular) shape. The first end surface 96a is provided so as to surround the outer periphery of the cylindrical portion 96c.

[0102] A protrusion 96e is formed on the outer surface of the cylindrical portion 96c. The protrusion 96e protrudes outward (away from the central axis of the duct 50A) from an outer surface 96f of the cylindrical portion 96c. The protrusion 96e extends in a direction perpendicular to the insertion direction D1. In other words, the protrusion 96e is a ridge extending in the circumferential direction of the cylindrical portion 96c. The protrusion 96e may be formed around the entire circumference of the cylindrical portion 96c, or may be formed around only a portion of the entire circumference of the cylindrical portion 96c. In this embodiment, the protrusion 96e is formed on each of the four outer surfaces 96f constituting the rectangular cylindrical portion 96c. The protrusion 96e protrudes in an arc shape from the outer surface 96f of the cylindrical portion 96c. A recess 96h recessed toward the outer surface is formed on the inner surface 96g of the cylindrical portion 96c at a position corresponding to the protrusion 96e.

[0103] As shown in FIG. 30, the second connection portion 97 has a second end face 97a that faces the first end face 96a. The second end face 97a is also a surface that is perpendicular to the insertion direction D1. The second end face 97a is a surface that is parallel to the first end face 96a. As shown in FIGS. 29 and 30, the second end face 97a is a surface that extends inward (toward the central axis of the duct 50B) from the outer peripheral surface 97b of the other duct 50B (third duct 55). The second end face 97a is a ring-shaped (quadratic ring-shaped) flat surface.

[0104] The second connecting portion 97 has a folded portion 97d folded back from an inner end portion 97c of the second end surface 97a toward the opposite side from the first end surface 96a (the opposite side from the insertion direction D1). The folded portion 97d may be formed around the entire circumference of the inner end portion 97c of the second end surface 97a, or may be formed around only a portion of the entire circumference of the inner end portion 97c of the second end surface 97a. In the present embodiment, the folded portion 97d is formed around the entire circumference of the inner end portion 97c of the second end surface 97a.

[0105] When one duct 50A (first duct 53) is inserted into the other duct 50B (third duct 55) and connected, the cylindrical portion 96c of the first connecting portion 96 is inserted into the other duct 50B (third duct 55) (see FIG. 30). In this state, the inner surface 97e of the folded portion 97d is located inside (closer to the center of) the tubular portion 96c relative to the apex (the outermost portion) of the protrusion 96e. Also, the front end 97f of the folded portion 97d in the insertion direction D1 is located behind the protrusion 96e in the insertion direction D1. This allows the folded portion 97d to be engaged with the cylindrical portion 96c, making it difficult for the other duct 50B (third duct 55) to fall off from the one duct 50A (first duct 53). In other words, the one duct 50A and the other duct 50B are connected.

[0106] The first duct 50A and the second duct 50B can be made of a flexible synthetic resin. As a result, when the first duct 50A and the second duct 50B are attached or detached from each other, the folded portion 97d is pushed by the protrusion 96e and bends outward (is elastically deformed). This makes it easy to attach or detach the first duct and the second duct. When one duct 50A (first duct 53) is inserted into the other duct 50B (third duct 55) and connected, the folded-back portion 97d abuts against or is close to an outer surface 96f of the cylindrical portion 96c (more specifically, a portion of the outer surface 96f that is further rearward in the insertion direction D1 than the protrusion 96e) (see FIG. 30). This makes it possible to eliminate or reduce rattling at the connection portion between the one duct 50A and the other duct 50B.

[0107] As described above, since the second connection portion 97 of the other duct 50B has the folded portion 97d, when the other duct 50B is manufactured by blow molding, the inner circumferential surface of the second connection portion 97 (the inner surface 97e of the folded portion 97d) can be manufactured with high precision. This point will be described below with reference to FIG. As shown in Figure 31, when the other duct 50B is manufactured by blow molding, first, heated resin is formed in an extruder into a container shape called a parison and expanded in a mold N1 to fit the shape of the mold (see the left diagram in Figure 31). Then, unnecessary portions are cut off with a cutter (the cut portion is indicated by arrow CT in Figure 31), completing the other duct equipped with a second connecting portion 97 having a folded portion 97d. The inner circumferential surface (the inner surface 97e of the folded portion 97d) of the second connecting portion 97 of the other duct 50B manufactured in this manner is molded by the surface of the mold N1, resulting in extremely high dimensional accuracy of the inner circumferential surface. Therefore, there is no rattle when it is connected to one of the ducts.

[0108] If the other duct is manufactured by blow molding in a shape that does not have the folded portion 97d as in the past, the inner circumferential surface of the connecting portion is formed by a cut surface (a surface cut manually), which results in low dimensional accuracy of the inner circumferential surface of the connecting portion, causing rattle when connected to one of the ducts. 30, a cushioning material 99 is interposed between the first end surface 96a and the second end surface 97a. The cushioning material 99 is made of an elastic material such as rubber. For example, the cushioning material 99 may be made of EPDM (ethylene propylene diene rubber) as a base material.

[0109] The cushion material 99 is adhered to the first end surface 96a or the second end surface 97a. In the present embodiment, the cushion material 99 is adhered to the first end surface 96a. However, the cushion material 99 may also be adhered to the second end surface 97a. As shown in FIG. 29, the cushion material 99 is an annular (quadratic annular) member. The cushion material 99 is arranged so as to surround the outer periphery of the tubular portion 96c.

[0110] When one duct 50A (first duct 53) is inserted into the other duct 50B (third duct 55) and connected, the cushion material 99 is sandwiched between the first end surface 96a and the second end surface 97a. In this state, the cushion material 99 abuts against the first end surface 96a and the second end surface 97a. In this state, the cushion material 99 may abut against the first end surface 96a, the second end surface 97a, and the outer surface of the cylindrical portion 96c.

[0111] According to the above-described duct connection structure, the cushioning material 99 is interposed between the first end face 96a perpendicular to the insertion direction D1 and the second end face 97a opposite the first end face 96a, so when one duct 50A and the other duct 50B are attached or detached, the inner surface of the duct does not rub against the outer surface of the cushioning material 99. This makes it possible to prevent the cushioning material 99 from peeling off when one duct 50A and the other duct 50B are attached or detached.

[0112] In conventional duct connection structures (e.g., the connection structure disclosed in Patent Document 1), when one duct is attached to another duct, the inner surface of the duct rubs against the outer surface of the cushion material 99. Therefore, if a cushion material 99 made of a highly adhesive material (e.g., EPDM) is used, the cushion material 99 will stick to the duct and peel off when the duct is attached to another duct. This forces the use of a cushion material made of a low-adhesion material, which may result in insufficient sealing at the connection. However, with the duct connection structure described above, the inner surface of the duct does not rub against the outer surface of the cushion material 99 when the ducts are attached to or detached from each other, so a cushion material made of a highly adhesive material (e.g., EPDM) can be used, improving the sealing at the connection.

[0113] The above-described duct connection structure (the connection structure between one duct 50A and the other duct 50B) can also be applied to a case where one duct 50A is a relay duct 51 and the other duct 50B is a switching box 52. In other words, as shown in FIG. 14, it can also be applied to a connection structure between a relay duct 51 and a switching box 52. The above-described duct connection structure can also be applied to a case where one duct 50A is a switching box 52 and the other duct 50B is a first duct 53. That is, as shown in Fig. 14, it can also be applied to a connection structure between a switching box 52 and a first duct 53.

[0114] The above-described duct connection structure can also be applied to a case where one duct 50A is a switching box 52 and the other duct 50B is a second duct 54. That is, as shown in FIG. 14, it can also be applied to a connection structure between a switching box 52 and a second duct 54. The above-described duct connection structure can also be applied to a case where one duct 50A is the second duct 54 and the other duct 50B is the fourth duct 56. That is, as shown in Fig. 32, it can also be applied to a connection structure between the second duct 54 and the fourth duct 56.

[0115] The above-mentioned work machine 1 comprises a body 2, a cabin 5 mounted on the body 2, a driver's seat 6 arranged inside the cabin 5, and an air conditioner main body 29 that generates conditioned air to be supplied inside the cabin 5, and an outside air inlet 34 is provided on the back 5b side of the cabin 5 to take in outside air that is introduced into the air conditioner main body 29. According to this configuration, the outside air inlet 34 is provided on the back side of the cabin 5, where a larger space can be secured compared to the side sides of the cabin 5. Therefore, it is possible to increase the size of the filter for removing foreign matter from the air taken in through the outside air inlet 34. This makes it possible to arrange a high-performance filter (for example, Category 2 of the EN standard, MARV-16 of the OSHA standard, etc.) as the filter (first filter 71). It is also possible to arrange another filter (second filter 72, mesh body 86, etc.) in addition to the first filter 71. Furthermore, because the filter can be made larger, it is possible to increase the amount of outside air introduced that passes through the filter.

[0116] The air conditioner main body 29 is disposed behind the driver's seat 6. According to this configuration, it is possible to shorten the duct (duct structure 50) that guides the outside air introduced from the outside air inlet 34 to the air conditioner main body 29. As a result, the outside air introduced from the outside air inlet 34 can be supplied to the air conditioner main body 29 over a short distance. Therefore, it is possible to reduce the installation space inside the cabin 5 for the duct that guides the outside air introduced from the outside air inlet 34 to the air conditioner main body 29. Furthermore, because the duct can be shortened, it is possible to reliably draw in outside air from the outside air inlet 34.

[0117] A rear cover 77 is attached to the rear surface 5b of the cabin 5, protruding rearward from the rear surface 5b, and the outside air inlet 34 is provided in the rear cover 77. According to this configuration, the rear cover 77 can ensure a large space behind the driver's seat 6 in which the air conditioner main body 29 and the like can be installed. Therefore, a large space behind the driver's seat 6 in which the air conditioner main body 29 and the like can be installed can be ensured without increasing the size of the cabin 5 itself.

[0118] The rear cover 77 has an openable and closable lid 81, and the outside air inlet 34 is provided in the lid 81. According to this configuration, by opening the cover 81, maintenance such as replacement of the filter through which the outside air introduced from the outside air inlet 34 passes can be easily performed. The work machine 1 also includes a first filter 71 that removes foreign matter contained in the outside air taken in through the outside air inlet 34, and an outside air duct 66 that guides the outside air that has passed through the first filter 71 toward the air conditioner main body 29, and the first filter 71 is attached to the outside air duct 66.

[0119] According to this configuration, when the outside air taken in through the outside air inlet 34 is guided through the outside air duct 66 to the air conditioner main body 29, foreign matter contained in the outside air can be reliably removed by the first filter 71. The work machine 1 also includes a second filter 72 that has a coarser mesh than the first filter 71 and is positioned between the outside air inlet 34 and the first filter 71, and a frame body 73 that fixes the second filter 72 and the first filter 71 to the outside air duct 66.

[0120] According to this configuration, the outside air taken in through the outside air inlet 34 can be passed through the second filter 72 and then supplied to the first filter 71, which makes the first filter 71 less likely to become clogged and extends the life of the first filter 71. Furthermore, the first filter 71 and the second filter 72 are released from their fixed positions by removing the frame 73, which makes it easy to replace the first filter 71 and the second filter 72.

[0121] The work machine 1 also includes a net 86 for catching insects, which is disposed between the outside air inlet 34 and the second filter 72. According to this configuration, insects and the like that enter through the outside air inlet 34 can be captured by the net body 86. Therefore, it is possible to prevent the second filter 72 from becoming clogged with insects and the like that enter through the outside air inlet 34, and it is possible to extend the life of the second filter 72.

[0122] A case 85 is attached to the front of the lid 81 to accommodate a removably disposed mesh 86. According to this configuration, the net body 86 can be easily attached, and the trapped insects and the like can be removed by removing the net body 86 from the case 85. This prevents the net body 86 from becoming clogged.

[0123] The case 85 also has a front panel 85a that is positioned in front of the mesh body 86 and faces the outside air inlet 34, and the front panel 85a has an opening 85c that allows outside air taken in from the outside air inlet 34 to pass through, and the opening 85c is located at a higher position than the outside air inlet 34. According to this configuration, when the work machine 1 is washed with water, washing water that has entered through the outside air inlet 34 can be prevented from entering the opening 85c.

[0124] The case 85 also has a protruding portion 85g that protrudes from the front plate 85a toward the outside air inlet 34 and abuts against the front surface of the mesh body 86, and the protruding length of the protruding portion 85g increases from top to bottom. According to this configuration, when the case 85 is attached to the front of the lid 81, the protrusion 85g can press the mesh body 86 toward the lid 81. This allows the mesh body 86 to be positioned in contact with or close to the outside air inlet 34. Furthermore, because the protruding length of the protrusion 85g increases from top to bottom, at least the lower part of the protrusion 85g can be reliably contacted with the mesh body 86. Furthermore, because the protruding length of the protrusion 85g is shorter at the top, the mesh body 86 can be easily placed into the case 85 from above.

[0125] The work machine 1 also includes a body 2, a cabin 5 mounted on the body 2, a driver's seat 6 arranged inside the cabin 5, an air conditioner main body 29 that generates conditioned air to be supplied to the inside of the cabin 5, and a duct structure 50 that guides the conditioned air supplied from the air conditioner main body 29. The air conditioner main body 29 mixes cold air and warm air to generate conditioned air for cooling or heating. The duct structure 50 has a first duct 53 that circulates the conditioned air for cooling, a second duct 54 that circulates the conditioned air for heating, a switching box 52 that is connected to the first duct 53 and the second duct 54 and has a switching unit 52d that can switch between a first state in which the conditioned air supplied from the air conditioner main body 29 is circulated through the first duct 53 and a second state in which the conditioned air is circulated through the second duct 54, and a relay duct 51 that connects the air conditioner main body 29 and the switching box 52 and guides the conditioned air generated by the air conditioner main body 29 to the switching box 52.

[0126] According to this configuration, even if the conditioned air generated by the air conditioner main body 29 is taken out in a state in which the cold air and the hot air are not sufficiently mixed, the cold air and the hot air can be sufficiently mixed in the relay duct 51 before being led to the switching box 52. Therefore, the switching box 52 can be switched in a state in which the cold air and the hot air are sufficiently mixed. As a result, conditioned air for cooling or heating at an appropriate temperature in which the cold air and the hot air are sufficiently mixed can be led from the switching box 52 to the first duct 53 or the second duct 54.

[0127] The air conditioner main body 29 is disposed behind the driver's seat 6, and the duct structure 50 passes beside the driver's seat 6 and extends from behind the driver's seat 6 to in front of the driver's seat 6. According to this configuration, the air conditioner main body 29 is disposed behind the driver's seat 6, so the length from the air conditioner main body 29 to the switching box 52 can be increased. As a result, the cool air and the warm air can be sufficiently mixed in the relay duct 51 before being guided to the switching box 52. Furthermore, compared to when the air conditioner main body 29 and the duct structure 50 are disposed below the driver's seat 6, a larger space can be secured around the feet of the operator sitting in the driver's seat 6.

[0128] In addition, the work machine 1 is equipped with a control device (right control device 21) arranged to the side of the driver's seat 6, and the first duct 53 is arranged between the inner wall surface 5a of the cabin 5 on the side where the control device (right control device 21) is arranged and the control device (right control device 21). According to this configuration, the first duct 53 can be disposed so as to pass in the front-to-rear direction near the side of the operator sitting in the driver's seat 6. Therefore, it becomes possible to blow out conditioned air for cooling from the first duct 53 near the operator sitting in the driver's seat 6 (for example, near the operator's face).

[0129] The first duct 53 also has a first outlet 53d, and the first outlet 53d includes a front outlet 53d1 that opens to the side of the driver's seat 6 and above the control device (right control device 21). According to this configuration, conditioned air for cooling can be blown out from the front outlet 53d1 near the face of the operator sitting in the driver's seat 6. This provides the operator with a strong feeling of freshness. Furthermore, conventionally, the first outlet 53d was provided near the display device 33 in front of the driver's seat 6, making it difficult to increase the size of the display device 33. However, by arranging the first outlet 53d at a position away from the display device 33, it is now possible to increase the size of the display device 33.

[0130] The first air outlet 53d also includes a rear air outlet 53d2 that opens behind the driver's seat 6. According to this configuration, conditioned air for cooling can be blown out from the rear outlet 53d2 near the back of the head of the operator sitting in the driver's seat 6. Therefore, a strong feeling of coolness can be given to the operator.

[0131] The switching box 52 is disposed to the side of the driver's seat 6. According to this configuration, it is possible to blow out conditioned air of an appropriate temperature inside switching box 52, in which cold air and hot air are sufficiently mixed, near driver's seat 6. Furthermore, if air conditioner main body 29 is disposed behind driver's seat 6, the length from air conditioner main body 29 to switching box 52 can be increased. Therefore, cold air and hot air can be sufficiently mixed in relay duct 51 before being led to switching box 52.

[0132] The duct structure 50 also extends in the front-to-rear direction, passing below the control device (right control device 21). According to this configuration, the duct structure 50 can be extended long in the front-rear direction at a position where it does not interfere with the operator sitting in the driver's seat 6. In addition, the first duct 53 has a flat portion (third portion 53c) whose length in the aircraft width direction is shorter than its length in the front-to-rear direction, and the flat portion is arranged between the control device (right control device 21) and the inner wall surface 5a of the cabin 5.

[0133] According to this configuration, the flat portion (third portion 53c) of the first duct 53 can be disposed near the operator sitting in the driver's seat 6. Therefore, conditioned air for cooling (cooled conditioned air) can be blown out near the face of the operator sitting in the driver's seat 6. In addition, by blowing out the cool conditioned air near the operator's face, the wind speed of the cool conditioned air hitting the area around the operator's face can be increased.

[0134] The flattened portion (third portion 53c) has a front outlet 53d1 at its front portion and a rear outlet 53d2 at its rear portion. According to this configuration, conditioned air for cooling can be blown out from the front air outlet 53d1 near the face of the operator sitting in the driver's seat 6, and conditioned air for cooling can be blown out from the rear air outlet 53d2 near the back of the operator's head.

[0135] In addition, the first duct 53 has a main body portion (first portion 53a) that connects the switching box 52 and the third duct 55 located in front of the first duct 53, and a flat portion (third portion 53c) that rises upward from the main body portion along the inner wall surface 5a of the cabin 5, and the length of the flat portion in the width direction of the aircraft is shorter than the length of the main body portion in the width direction of the aircraft. According to this configuration, the conditioned air can be guided from the switching box 52 to the third duct 55 using one duct (first duct 53), and the conditioned air can also be guided upward along the inner wall surface 5a of the cabin 5.

[0136] In addition, relay duct 51 is provided with an expanded flow path portion 51f in which the flow path cross-sectional area expands from the air conditioner main body 29 side toward the switching box 52 side. According to this configuration, the flow rate of the air flowing through the relay duct 51 decreases as it moves from the air conditioner main body 29 side to the switching box 52 side, so that the cold air and the warm air can be reliably mixed within the relay duct 51.

[0137] The work machine 1 also includes a body 2, a cabin 5 mounted on the body 2, an air conditioner main body 29 that generates conditioned air to be supplied to the interior of the cabin 5, and a duct structure 50 that guides the conditioned air supplied from the air conditioner main body 29, the duct structure 50 including one duct 50A and another duct 50B that are connected to each other, the one duct 50A having a first connection portion 96 that is inserted into and connected to the other duct 50B, the other duct 50B having a second connection portion 97 into which the one duct 50A is inserted and connected, the first connection portion 96 having a first end face 96a that is perpendicular to the insertion direction, the second connection portion 97 having a second end face 97a that faces the first end face 96a, and a cushioning material 99 interposed between the first end face 96a and the second end face 97a.

[0138] According to this configuration, the cushion material 99 is interposed between the first end surface 96a perpendicular to the insertion direction and the second end surface 97a opposite the first end surface 96a, so when one duct 50A and the other duct 50B are attached or detached, the ducts do not rub against the cushion material 99. Therefore, it is possible to prevent the cushion material 99 from peeling off when one duct 50A and the other duct 50B are attached or detached.

[0139] The first end face 96a is an annular surface extending inward from the outer peripheral surface of one duct 50A, the second end face 97a is an annular surface extending inward from the outer peripheral surface of the other duct 50B, and the cushion material 99 is an annular member abutting the first end face 96a and the second end face 97a. With this configuration, the cushioning material 99 can be interposed between the first end face 96a and the second end face 97a around the entire circumference of the connection between one duct 50A and the other duct 50B, resulting in excellent sealing properties at the connection.

[0140] The second connection portion 97 also has a folded portion 97d folded back from an inner end portion 97c of the second end surface 97a toward the opposite side to the first end surface 96a. According to this configuration, since the second connection portion 97 of the other duct 50B has the folded portion 97d, when the other duct 50B is manufactured by blow molding, the inner peripheral surface of the second connection portion 97 (the inner surface 97e of the folded portion 97d) can be manufactured with high dimensional accuracy. Therefore, the other duct 50B having the second connection portion 97 with high dimensional accuracy can be manufactured inexpensively. In addition, the adhesion of the connection portion between the one duct 50A and the other duct 50B is improved.

[0141] In addition, the first connection portion 96 has a cylindrical portion 96c extending from the inner end portion 96b of the first end face 96a toward the other duct 50B, and a protrusion 96e is formed on the outer surface of the cylindrical portion 96c to engage with the folded portion 97d. According to this configuration, the folded portion 97d is formed on the protrusion 96e, so that the duct 50B is less likely to fall off from the duct 50A.

[0142] Furthermore, the folded portion 97d comes into contact with the outer surface of the cylindrical portion 96c when the duct 50A on one side and the duct 50B on the other side are connected. According to this configuration, when one duct 50A and the other duct 50B are connected, the other duct 50B is less likely to come off from the one duct 50A. Furthermore, the cushion material 99 comes into contact with the first end surface 96a, the second end surface 97a, and the outer surface of the cylindrical portion 96c when the duct 50A on one side and the duct 50B on the other side are connected.

[0143] According to this configuration, when one duct 50A and the other duct 50B are connected, the sealing performance of the connection between one duct 50A and the other duct 50B can be improved. The cushion material 99 is adhered to the first end surface 96a or the second end surface 97a. This configuration can more reliably prevent the cushion material 99 from falling off.

[0144] Although one embodiment of the present invention has been described above, the embodiment disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0145] 1 Work equipment 2 aircraft 5 Cabins 29 Air conditioner unit 50 Duct structure 50A One duct 50B Other duct 96 First connection part 96a 1st end face 96b Inner end 96c Cylindrical part 96e protrusion 97 Second connection part 97a 2nd end face 97d Folded part 99 Cushioning material

Claims

1. The aircraft and a cabin mounted on the aircraft; an air conditioner main body that generates conditioned air to be supplied to the interior of the cabin; a duct structure for guiding conditioned air supplied from the air conditioner main body; Equipped with the duct structure includes one duct and another duct that are connected to each other, the one duct has a first connection portion that is inserted into and connected to the other duct, the other duct has a second connection portion into which the one duct is inserted and connected, the first connection portion has a first end surface perpendicular to the insertion direction, the second connection portion has a second end surface facing the first end surface, a cushioning material is interposed between the first end surface and the second end surface; the first end surface is an annular surface extending inward from an outer circumferential surface of the one duct, the second end surface is an annular surface extending inward from an outer circumferential surface of the other duct, the cushion material is an annular member that contacts the first end surface and the second end surface, the second connection portion has a folded portion folded back from an inner end portion of the second end surface toward a side opposite to the first end surface, an extension length of the second end surface from the outer circumferential surface to the inward direction is longer than a length of the folded-back portion in the insertion direction; the first connection portion has a cylindrical portion extending from an inner end portion of the first end surface toward the other duct, a protrusion for engaging the folded portion is formed on the outer surface of the cylindrical portion; The protrusion protrudes in an arc shape from the outer surface of the cylindrical portion, a recess formed on the inner surface of the cylindrical portion at a position corresponding to the protrusion, the recess being recessed toward the outer surface; The work machine, wherein the protrusion is integrally connected to the first end surface, and the folded portion is integrally connected to the second end surface.

2. A work machine as described in Claim 1, wherein the folded portion abuts against the outer surface of the tubular portion when the one duct and the other duct are connected.

3. A work machine as described in Claim 1, wherein the cushioning material abuts against the first end face, the second end face and the outer surface of the tubular portion when the one duct and the other duct are connected.

4. A work machine as described in Claim 1, wherein the cushioning material is adhered to the first end surface or the second end surface.

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