JP2610723B2 - Agricultural work machine engine cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine cooling device for an agricultural work machine which is configured to transmit power from an output shaft of an engine mounted on a traveling machine body to a cooling fan of a radiator through a forward / reverse switching mechanism. .

[0002]

2. Description of the Related Art Conventionally, in an engine cooling device for a mobile agricultural machine, an electromagnetic clutch is interposed between an engine output shaft and a radiator cooling fan as disclosed in, for example, Japanese Utility Model Laid-Open No. 3-32122. A dust-blowing fan, which is driven by the electric motor in the direction opposite to the radiator cooling fan, and controls the electromagnetic clutch to be turned off and the electric motor to be turned on at the same time as the forward / reverse switching mechanism. was there.

[0003]

However, in the above-mentioned conventional structure, a dust blowing fan is required in addition to the radiator cooling fan, and an electric motor and its electric control mechanism are also required. In many cases, the structure is complicated and the cost is high. An object of the present invention is to eliminate the above-mentioned disadvantages by rational structure improvement.

[0004]

According to a first feature of the present invention, in the engine cooling device for a mobile agricultural machine described at the beginning, the forward / reverse switching mechanism is switched from a rotation state of a radiator cooling fan to a reverse rotation state. A hydraulic actuator is provided to branch from a pressure oil supply path for a hydraulic braking mechanism for body turning in a traveling body and supply pressure oil to the hydraulic actuator, and the hydraulic braking mechanism is brought into a pressure oil supply state. The point is that control means for supplying pressure oil to the hydraulic actuator only for a predetermined time from the time of the switching is interposed in the hydraulic system.

A characteristic feature of the second invention is that a hydraulic actuator for switching the forward / reverse switching mechanism from a radiator cooling fan rotation state to a reverse rotation state is provided, and a hydraulic oil supply path for a lifting / lowering drive hydraulic device of a working device is provided. The hydraulic system is configured to supply pressure oil to the hydraulic actuator by branching, and control means for supplying the hydraulic oil to the hydraulic actuator only for a predetermined time from the time when the operation of the hydraulic device is switched is interposed in the hydraulic system. It is in.

[0006]

According to the characteristic structure of the first aspect of the present invention, in the operation of the fuselage, when the turning braking mechanism is operated, for example, for headland turning in a field, the hydraulic actuator is actuated and the fan for cooling the radiator is rotated. From the state, the cooling fan is switched to the reverse rotation state, and the dust attached to the dustproof net is blown outward. In addition, the cooling fan can effectively perform the cooling function of the radiator during normal straight traveling work, and can blow off dust adhering to the radiator during the regular turning operation of the body. Moreover, since the supply of the pressure oil to the hydraulic actuator is performed only for a predetermined time, even when the turning operation takes time, the branch supply of the pressure oil is only required for a short time necessary only for the dust blowing action, Low loss of hydraulic power.

According to the characteristic structure of the second invention, when the working device is driven, the hydraulic oil for the lifting / lowering drive hydraulic device is branched and supplied to the hydraulic actuator, so that dust can be blown off as described above. And even if it takes a long time to perform the lifting and lowering operation, the branch supply of the pressure oil is only required for a short time necessary only for the dust blowing action,
Low loss of hydraulic power.

[0008]

Accordingly, in this kind of agricultural work machine, cooling is performed by using a hydraulic braking mechanism generally provided for performing a turning run with a small radius or a hydraulic source of a hydraulic device for raising and lowering the working device. Since the fan is rotated in the normal and reverse directions, it is possible to reliably blow out the attached dust regularly, and the structure can be simplified by eliminating the need for a fan dedicated to blowing off and a dedicated driving mechanism. Further, with the rational configuration, it is possible to minimize the loss of the hydraulic operation due to the effective use of the existing hydraulic source.

[0009]

Embodiments will be described below with reference to the drawings. FIG.
Shows a combine, which is an example of an agricultural work machine. The combine mounts and supports an engine 2 on an airframe 1, mounts and supports a driver's seat 4 on an upper surface of a driving unit cover 3 that covers the engine 2, and also includes a lateral portion and a rear side of the driving unit cover 3. The portion is provided with an external air intake portion for cooling the engine. As shown in FIG. 4, a cooling radiator 5 is provided at a location outside the body of the engine 2, and the radiator 5 is cooled by sucking outside air from the outside air suction unit by a fan 6 driven by the engine 2. It is composed. That is, the radiator 5 is arranged at a position outside the body of the engine 1, and the fan 6 is arranged between the engine 2 and the radiator 5. Further, an intake duct 7 forming an outside air intake path connected to the intake portion of the radiator 5 is provided in a state extending across the lateral side and the rear side of the driving unit 8. In the intake duct 7, an outside air intake section 9 is formed on each of a side portion of the driving section 8, a side section of the driver's seat 4, and a rear section of the driving section 8. Is stretched out.

Above the driver's seat 4 is a grain tank 3
Sun shade 37 via a bracket 36 provided on the upper surface of 5
Is cantilevered. The awning 37 is configured so that the height can be adjusted according to the difference between the driver's sitting state and the standing posture. That is, as shown in FIG.
7 is pivotally supported by a pin 39 in a long hole 38 formed in the bracket 36 so as to be vertically adjustable, and a plurality of locking portions 40 formed in the middle along the long hole 41 of the bracket 36. The height can be adjusted by selectively engaging with 42. The lower end of the elongated hole 41 constitutes a locking portion 42a during storage.

FIG. 1 shows a turning hydraulic circuit of the combine. In other words, in the combine, the clutch brake mechanisms 26, 26 (an example of a hydraulic brake mechanism) are interposed in the respective transmission systems for the pair of left and right crawler traveling devices CL, CL.
6 are driven by hydraulic cylinders 27R and 27L, respectively.
When the hydraulic piston 28 reaches the clutch release position,
Subsequent supply oil is a variable relief valve 2 for adjusting brake pressure.
9, and the switching control valve 31 of each of the hydraulic cylinders 27R and 27L and the variable relief valve 29 are connected to a single operating lever 32 disposed in the body control section. It is configured to be operated by. That is, when the operation lever 32 is operated from the neutral position N to the left or right, the hydraulic cylinders 27R, 2R in the operation direction are operated.
When the clutch 7L is actuated, the clutch is disengaged, and further operation is performed, the relief pressure of the variable relief valve 29 according to the operation amount changes, and a braking force corresponding to the operation amount is applied.

The power from the output shaft 11 of the engine 2 is transmitted to the radiator cooling fan 6 via the forward / reverse switching mechanism A. That is, as shown in FIGS. 2 and 3, a state in which the first transmission belt 12 that is constantly rotated and driven by the output shaft 11 is stretched, and is pressed against the inner peripheral surface of the first transmission belt 12 and driven to rotate. A forward pulley 13 that can be switched to a state in which transmission is cut off by separating from the first transmission belt 12, and a reverse rotation that can be switched to a state in which the transmission is cut off by pressing against the outer peripheral surface of the first transmission belt 12. A second transmission belt 16 is wound and stretched over each of the pulley 14 for use and the driven pulley 15 of the cooling fan 6,
The forward-reverse pulley 13 and the reverse-rotation pulley 14 are provided so as to be able to reciprocally switch to a transmission state, thereby constituting the forward-reverse rotation switching mechanism A. More specifically, the first transmission belt 12 includes a drive pulley 17 attached to the engine output shaft 11, a driven pulley 19 for a water pump 18 for circulating engine cooling water, and a driven pulley 21 for a dynamo 20.
Each of them is wound and stretched, and the support shaft 22 of the cooling fan 6 is arranged on the same axis as the driven pulley 19 for the water pump. A pulley support member 24 is externally fitted to the fan support shaft 22 so as to be rotatable relative to the support shaft center, and the forward pulley 13 and the reverse pulley 14 are supported on the pulley support member 24. A second transmission belt 16 is wound and stretched over each of the pulleys 13 and 14 and the driven pulley 15 of the cooling fan 6, and the forward pulley 13 and the reverse pulley 14 are configured in a double pulley structure. Then, each pulley 13, 1
4, the first pulley portions 13a, 14a
The transmission belt 12 is disposed at a position where the pressure can be freely pressed and separated.

The pulley support member 24 is provided with an operating arm 24a connected to the pulley support member 24 by means of a spring 25.
Is rotated in the direction in which it comes into pressure contact with the second transmission belt 16, and the forward rotation pulley 13 is driven by the hydraulic cylinder C (an example of a hydraulic actuator) that drives the operation arm 24a against the urging force of the spring 25. It is linked so as to be separated from the second transmission belt 16 and to switch to a state where the reverse rotation pulley 14 is pressed against the second transmission belt 16. Then, the hydraulic cylinder C is configured to branch off from the traveling brake pressure adjusting oil discharge passage 30 and supply pressure oil. Then, control means B for supplying pressure oil to the hydraulic cylinder C only for a predetermined time from the point in time when the hydraulic cylinder C is switched to the pressure oil supply state is interposed in the hydraulic system. More specifically, an electromagnetic three-position switching valve 3 is provided in the branch oil passage.
3, the switching valve 33 is configured to control the control device 34 to switch to the pressure oil supply side when the detection switch SW1 detects that the turning operation of the operation lever 32 has been performed. is there. Then, when the hydraulic cylinder C reaches the maximum extension position, this is indicated by the limit switch SW2.
The control device 34 controls the switching of the switching valve 33 to the neutral position, and after a lapse of a predetermined time, controls the switching to the oil drainage side so that the hydraulic cylinder C is retracted by the spring urging force. The control means B is configured in this manner. Therefore, the cooling fan 6 reverses for a predetermined time every time the airframe is turned, and blows out the dust adhering to the radiator suction part with the normal radiator cooling operation.

[Alternative Embodiment] The control means B may be constituted as follows. As shown in FIG. 5, a pressurized oil supply path to a hydraulic cylinder 44 (an example of a hydraulic device) for driving up and down a discharge conveyor 43 (an example of a working device) for discharging the grains in the grain tank 35. The pressure oil is branched and supplied to the reverse rotation hydraulic cylinder C. That is, from the pilot oil passage 47 of the pilot check valve 46 interposed on the lower side of the control three-position switching valve 45 of the lifting hydraulic cylinder 44 to the reverse rotation hydraulic cylinder C via the electromagnetic three-position switching valve 33. When the detection switch SW3 detects that the control three-position switching valve 45 has been operated to move down, the control device 34 switches the electromagnetic three-position switching valve 33 to the pressure oil supply position. When the reverse rotation hydraulic cylinder C reaches the maximum extension position, this is detected by the limit switch SW2, and the control device 3
4 switches the electromagnetic three-position switching valve 33 to the neutral position, and after a predetermined time elapses, controls to switch to the lowered position.

In the claims, reference numerals are provided to facilitate comparison with the drawings, but the present invention is not limited to the configuration shown in the accompanying drawings.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram

FIG. 2 is a side view of a forward / reverse switching mechanism.

FIG. 3 is a simplified front view of a forward / reverse switching mechanism.

FIG. 4 is a front view of a driving unit.

FIG. 5 is a hydraulic circuit diagram of another embodiment.

FIG. 6 is an overall side view of the combine.

FIG. 7 is a side view of the sunshade support.

[Explanation of symbols]

 2 Engine 5 Radiator 6 Cooling fan 11 Output shaft 26 Braking mechanism 43 Work device 44 Hydraulic device A Forward / reverse rotation switching mechanism B Control means C Hydraulic actuator

Claims (2)

(57) [Claims] 1. A forward / reverse switching mechanism (A) for switching power from an output shaft (11) of an engine (2) mounted on a traveling body.
An engine cooling device for an agricultural work machine configured to transmit a cooling fan (6) of a radiator (5) via a radiator (5) from a rotating state of a fan for cooling the radiator (5). A hydraulic actuator (C) for switching operation to the reverse rotation state is provided, and a hydraulic oil is supplied to the hydraulic actuator (C) by branching off from a hydraulic oil supply path for a hydraulic braking mechanism (26) for body turning in the traveling body. Control means (B) for supplying pressure oil to the hydraulic actuator (C) only for a predetermined time from the point in time when the hydraulic braking mechanism (26) is switched to the pressure oil supply state.
An engine cooling device for agricultural work equipment with a hydraulic system interposed. 2. A forward / reverse switching mechanism (A) for switching power from an output shaft (11) of an engine (2) mounted on a traveling vehicle body.
An engine cooling device for an agricultural work machine configured to transmit a cooling fan (6) of a radiator (5) via a radiator (5) from a rotating state of a fan for cooling the radiator (5). A hydraulic actuator (C) for switching operation to the reverse rotation state is provided, and a hydraulic oil is supplied to the hydraulic actuator (C) by branching off from a hydraulic oil supply path for a hydraulic device (44) for raising and lowering the working device (43). And a control means (B) for supplying pressure oil to the hydraulic actuator (C) for a predetermined time from the switching point of the operation of the hydraulic device (44). apparatus.