JP2535949Y2 - Engine cooling device - 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 provided in a combine or other agricultural work vehicle, for example.
More specifically, the present invention relates to an engine cooling device configured to transmit power from an output shaft of an engine to a radiator cooling fan via a forward / reverse switching mechanism.

[0002]

2. Description of the Related Art Conventionally, in the above-mentioned engine cooling apparatus, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2-217664, a gear mesh type positive gear is provided between an engine crankshaft and a radiator cooling fan drive shaft. A structure in which a reverse rotation switching mechanism is interposed has been proposed.

[0003]

However, according to the conventional structure described above, since the gear meshing type switching mechanism is interposed, there is a drawback that the driving noise is increased, and the drive shaft which rotates continuously at high speed is required. On the other hand, since the structure is such that the normal rotation state is immediately switched to the reverse rotation state, there is also a disadvantage that the drive structure becomes complicated for smooth operation. Therefore, as a means to solve the above disadvantages,
As disclosed in JP-A-5-100027, there is a means for driving a radiator cooling fan via a forward drive belt and a reverse drive belt. In this structure, the fan drive belt wound around the output pulley of the engine crankshaft and the input pulley of the radiator cooling fan is used as a normal rotation belt, and the rotation from the dynamo rotated by the engine to the reverse rotation of the radiator cooling fan. A belt for reverse rotation of the fan for transmitting power for the fan is provided, and a tension pulley for the belt for normal rotation of the fan and a tension pulley for the belt for reverse rotation of the fan are selectively switched, so that the radiator cooling fan can be rotated forward and backward. In this case, the forward / reverse rotation of the fan is switched by the pressure contact / separation of the pulley with respect to the transmission belt, so that the impact accompanying the switching is small and the driving noise during transmission is also small. In addition, since it is constituted by the transmission belt and the pulley, high-precision machining or the like, unlike a gear-type switching mechanism, is unnecessary, the number of parts is small, and the structure can be simplified.
However, since the belt tension changes greatly every time the rotation is switched between forward and reverse, excessive tension and slip are likely to occur, and it is difficult to maintain the belt tension properly. There is. An object of the present invention is to eliminate the above-mentioned disadvantages.

[0004]

According to a first aspect of the present invention, in the first aspect, a first power transmission belt which is constantly driven to rotate by the output shaft is stretched, and the first power transmission belt includes a first power transmission belt. A forward rotation pulley that can be switched between a state in which the roller rotates in contact with the peripheral surface and a state in which the transmission is separated and separated,
The second transmission belt is connected to a reverse rotation pulley which can be switched between a state in which the transmission belt is driven to rotate by pressing against the outer peripheral surface of the first transmission belt and a state in which the transmission is cut off, and a driven pulley of the cooling fan. In addition to being wound and stretched, the forward and reverse rotation pulleys are provided so as to be able to reciprocally switch to a transmission state in a reciprocal manner to constitute the forward and reverse rotation switching mechanism.

[0005]

According to this configuration, when the forward rotation pulley is in pressure contact with the first transmission belt and is in the transmission state, the cooling fan sucks outside air to perform a normal radiator cooling operation. Even when dust adheres to the suction part of the radiator, if the pulley for normal rotation separates and the pulley for reverse rotation comes into pressure contact with it at the same time as the transmission state, the cooling fan rotates in the reverse direction and flows outward through the radiator. This causes dust adhering to the suction portion of the radiator to be blown outward.

[0006]

Therefore, normal cooling operation can be performed by rotating the cooling fan forward, and dust adhering to the radiator suction part can be blown off by periodically rotating the cooling fan, While suppressing early clogging due to the accumulation of dust and maintaining a smooth engine cooling operation for a long period of time, the engine output shaft continues to rotate at high speed during operation of the engine, but the pulley with respect to the transmission belt Since the structure is such that the forward / reverse rotation of the fan is switched depending on the pressure contact / separation, the impact accompanying the switching is small, and the driving noise during transmission is also small. In addition, since the first transmission belt and the second transmission belt can be used while maintaining proper tension, excessive tension and slip are unlikely to occur, so that reduction in transmission efficiency is suppressed, and further, the durability of the transmission belt is reduced. Performance can be improved.

[0007]

Embodiments will be described below with reference to the drawings. FIG.
Shows the prime mover of the combine. An engine 2 is mounted and supported on an airframe 1, and a driver's seat 4 is mounted and supported on an upper surface of a driving unit cover 3 that covers the engine 2, and an engine is provided on a lateral side and a rear side of the driving unit cover 3. An external air intake for cooling is formed. 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 portion by a fan 6 driven by the engine 2. 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.

[0008] 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. 1 and 2, a first transmission belt 12 that is constantly driven to rotate by the output shaft 11 is stretched.
A forward pulley 13 that can be switched between a state in which the inner peripheral surface of the first transmission belt 12 is driven to rotate and a state in which the transmission is separated and a state in which the transmission is cut off; A second transmission belt 16 is wound around a pulley 14 for reverse rotation that can be switched to a state in which transmission is interrupted, and a driven pulley 15 of the cooling fan 6. The forward / reverse rotation switching mechanism A is configured by providing a reverse rotation pulley 14 so as to be able to reciprocally switch to a transmission state. More specifically, the first transmission belt 12 is wound around a driving 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, respectively. The spindle 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. The pulleys 13 and 14 and the cooling fan 6
A second transmission belt 16 is wound and stretched over the driven pulley 15 to form the forward pulley 13 and the reverse pulley 14 in a double pulley structure.
The first pulley portions 13a and 14a of the first transmission belt 14 are disposed at positions where they can be pressed into contact with and separated from the first transmission belt 12.

The pulley support member 24 is urged by a spring 25 in a direction in which the forward rotation pulley 13 comes into pressure contact with the second transmission belt 16, and at the same time, a cutting pre-processing unit (not shown) at the front of the machine body is raised. In conjunction with the operation, the pulley 13 for the forward rotation is separated from the second transmission belt 16 by the pulling operation of the wire 26, and at the same time, the pulley 14 for the reverse rotation is switched to a state of being pressed against the second transmission belt 16. In this way, the cooling fan 6 is rotated in reverse every time the cutting pre-processing unit is raised, and blows out the dust attached to the radiator suction unit in the normal radiator cooling operation. The linkage between the raising operation of the mowing pre-processing unit and the pulley switching operation may be provided so as to be able to be intermittently operated, or may be configured to be switched in conjunction with the machine steering operation.

[0010] In the claims of the utility model registration, reference numerals are written to facilitate comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is a side view of a forward / reverse switching mechanism.

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

FIG. 3 is a front view of a driving unit of the combine.

[Explanation of symbols]

 2 Engine 5 Radiator 6 Cooling fan 11 Output shaft 12 First transmission belt 13 Pulley for forward rotation 14 Pulley for reverse rotation 15 Follower pulley A Forward / reverse rotation switching mechanism

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Nobuo Yuki 64, Ishizukita-cho, Sakai-shi, Osaka Kubota Sakai Works Co., Ltd. (56) Reference Reference

Claims (1)

(57) [Scope of request for utility model registration] An engine cooling device configured to transmit power from an output shaft (11) of an engine (2) to a radiator (5) cooling fan (6) via a forward / reverse switching mechanism (A). A first transmission belt (12), which is constantly rotated and driven by the output shaft (11), is stretched, and is separated from a state in which the first transmission belt (12) is brought into pressure contact with the inner peripheral surface of the first transmission belt (12) and driven to rotate. A forward rotation pulley (13) that can be switched to a state in which transmission is interrupted, and a reverse rotation that can be switched to a state in which the transmission is interrupted by being separated from a state in which the outer peripheral surface of the first transmission belt (12) is pressed against the outer peripheral surface of the first transmission belt (12) for drive rotation. A second transmission belt (16) is wound around each of the pulley (14) for driving and the driven pulley (15) of the cooling fan (6), and the pulley (13) for forward rotation and the reverse The pulley (14) is reciprocally transmitted. The engine cooling device is provided so as to be switchable and constitutes the forward / reverse switching mechanism (A).