JP2000102311A - Driving mechanism of reaping blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving mechanism of a reaping blade capable of improving the cutting performance of a culm, surely cutting the base of a culm and preventing clogging trouble, etc., by constituting a specific stepless speed- changing mechanism with a driving pulley and a driven pulley to enable the change of the driving speed of the reaping blade by the mechanism and increasing the driving speed even at a low-speed traveling mode of the reaping machine. SOLUTION: A driven pulley 72a is placed above a reaping blade 74 and the reaping blade 74 is reciprocated by the driven pulley 72a through a crank mechanism. A belt 78 is extended between the driven pulley 72a and a driving pulley 70a placed above the reaping frame to drive the reaping blade 74 with the belt-driving mechanism. In a combine having the above construction, either one or both of the driving pulley 70a and the driven pulley 72a are constructed with a split pulley to constitute a split pulley stepless speed-changing mechanism and the driving speed of the reaping blade is varied by the stepless speed- changing mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for driving a cutting blade of a cutting unit which is disposed at the front of a combine, raises a grain stalk, cuts, and transports it to a threshing unit.

[0002]

2. Description of the Related Art Conventionally, harvesting work by combine has been
A mowing part is arranged at the front of the machine body, the cereal culm is raised by the tine of a raising case disposed at the front part of the mowing part, and the culm is raised by the mowing blade disposed at the lower part behind the case. Is cut off, and the cut culm is transported rearward and upward by a transporting unit arranged at the rear of the cutting unit, and delivered to the feed chain of the threshing unit.

[0003] The cutting blades arranged in the left-right direction of the machine reciprocate in the left-right direction. Receiving blades are also provided in the lower part of the cutting blades in the left-right direction of the machine. Is used to cut off the roots of rice, wheat, etc. The driving force of the cutting blade is transmitted to a cutting crank, a rod, a cutting arm, and a knife head in order from a cutting transmission shaft disposed in the cutting frame in the left-right direction. The cutting blade fixed to the lower part of the knife head is reciprocated by the movement.

[0004]

However, in the above-mentioned prior art, the crank motion of the cutting blade, the cutting blade crank, the cutting arm, etc. is the source of vibration, so that the vibration becomes large during high-speed work, which is not suitable. In order to realize high-speed work, a W-action cutting blade that reciprocates the cutting blade right and left simultaneously in the opposite direction, and an opposing cutting blade system were used to drive the vibration to cancel the vibration, but the structure became complicated. Therefore, there is a problem that the cost is increased because the drive units are disposed on both the left and right sides. Since the driving of the cutting blade is configured to be synchronized with the vehicle speed, the speed of the reciprocating movement of the cutting blade becomes slow at a low speed, and the cutting performance of the culm was not sufficient.

[0005]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. That is, a driven pulley is disposed above the cutting blade, the cutting blade can be driven to reciprocate from the driven pulley via a crank mechanism, and a belt is provided between the driven pulley and a driving pulley provided on the cutting frame. , And the cutting blade is driven by a belt transmission mechanism, wherein one or both of the driving pulley and the driven pulley are formed of split pulleys, and a split pulley type continuously variable transmission mechanism is provided. And the cutting blade drive speed can be changed by the continuously variable transmission mechanism.

The split pulley comprises a fixed portion fixed to the drive shaft and a sliding portion slidable in the axial direction of the drive shaft and rotating integrally with the drive shaft. Part was slid with a cam.

Further, the sliding portion is driven by an actuator, the actuator and a vehicle speed sensor are connected to a controller, and control is performed so as to increase the driving speed of the cutting blade during low-speed running.

[0008]

Next, an embodiment of the present invention will be described.
1 is an overall side view of a combine equipped with a mowing device of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a side view of a mowing portion, FIG. 4 is a plan view of a mowing portion, and FIG. 6 is a plan view of the same, FIG. 7 is a side sectional view of the continuously variable transmission mechanism of the present invention, FIG. 8 is a plan view of the same, and FIG. FIGS. 10, 10 and 11 are diagrams showing the relationship between the vehicle speed and the cutting blade drive speed, and FIG. 12 is a skeleton diagram showing a drive transmission system of the cutting unit.

The overall structure of the combine will be described with reference to FIGS. 1 and 2. Airframe 2 on crawler-type traveling device 1
And an operating unit 3 is disposed on the front right side of the body frame 2 in the traveling direction, and the operating unit 3 has a front column 4
A steering lever, an accelerator lever and the like are arranged on the front column 4, a side column 5 is erected on the side of the front column 4 at the center of the fuselage, and a work clutch lever is mounted on the side column 5. And a gearshift lever.

A cutting section 6 projects forward from the left side of the body frame 2 in the traveling direction, raises the grain stalk, cuts the root by a cutting blade 74, and conveys it rearward by a conveying device. A threshing unit 7 is arranged behind the reaping unit 6,
While the stem of the grain stalks conveyed by the conveying device is pinched by the feed chain 8 and conveyed rearward, the grain is shed by the handling cylinder 9. The straw after threshing is conveyed backward by a straw chain 17 and processed by a straw processing device 11 such as a cutter or a binding device.

At the lower part of the threshing unit 7, a sorting device is disposed, and the second product sorted by the sorting device is returned to the handling cylinder 9 or the processing cylinder again, dust and the like are discharged, and fine particles are removed. It is conveyed to a Glen tank 13 arranged at the rear of the operation unit 3 via a numbering conveyor and a fry conveyor 12. A lower conveyor is disposed at a lower portion in the Glen tank 13, and the lower conveyor is communicated with a discharge auger 14. By driving the lower conveyor and the discharge auger 14, the grains in the Glen tank 13 can be discharged. I have to.

An engine 16 is disposed below the seat 15 in the driving unit 3 and transmits the driving force of the engine 16 to the crawler-type traveling device 1 to travel, and the reaping unit 6, the threshing unit 7, the sorting unit And the like, and successively harvesting, threshing and sorting operations, and storing the grains in the Glen tank 13.

Next, the construction of the mowing unit 6 will be described with reference to FIGS. 3, 4 and 12. FIG. Rotating fulcrum stands 20 and 21 are provided on the front part of the body frame 2, and a vertical rotating fulcrum shaft 22 composed of a pipe is pivotally supported on the rotating fulcrum stands 20 and 21,
A gear case 23 projects from one end of the vertically rotating fulcrum shaft 22, and a cutting input shaft (transmission 1) is provided inside the vertically rotating fulcrum shaft 22.
A shaft 19 is pivotally supported, and one end of the cutting input shaft 19 projects to the right in the traveling direction to fix the input pulley 24 so as to introduce the driving force from the engine 16 to the cutting unit 6. I have.

A vertical connecting pipe 25 projects forward and downward from the vertical rotation fulcrum shaft 22, and a transmission 2 shaft 25 a is disposed in the vertical connecting pipe 25. A hydraulic cylinder 26 for raising and lowering is interposed between the two so that the mowing part 6 can be turned up and down around the turning fulcrum shaft 22. At the front end of the vertical connecting pipe 25, a horizontal pipe 30 is supported in the lateral direction of the fuselage.
0, a cutting triaxial shaft 30a is laid horizontally, bevel gear cases 80, 81 are fixedly mounted on both sides of the horizontal pipe 30, and support plates 31, 31 are extended forward from the bevel gear cases 80, 81. The horizontal connecting frame 32 is fixed between the front portions of the plates 31 to support the cutting blade 74. In addition, the drive orthogonal shaft 82 is extended upward from the right bevel gear case 81 and extended to the front of the fuselage.
・ Power is transmitted to 35.

The cutting frames 33, 33,... Protrude forward from the horizontal connecting frame 32, and the cutting frames 33, 33,.
... are fixed. At the rear of the weeding plates 34, 34,..., There are raised cases 35, 35, 35, respectively, and the raised cases 35, 35, 35 are provided with tines 36, 36, respectively. In this embodiment, a chain is accommodated, and as shown in FIG. 4, the left side of the fuselage (FIG.
From the left), a two-row cut portion and a single-row cut portion are formed.

Next, the transport unit 10 located at the rear of the reaper 6
Will be described with reference to FIGS. 3 and 4. FIG. The cutting blade 7 is provided on the lower side between the rear portions of the cutting frames 33, 33,...
4 are arranged horizontally, and the cutting frames 33, 33,...
40 and the scraping belts 41, 41, 41 are arranged, and stock feeders 42L, 42R are further arranged on the upper rear side.
Above it, a left upper transfer device 43L and a left front spike transfer device 44L are arranged. In the rear part, the vertical transport device 45 and the upper rear transport device 46
However, as shown in FIG. 4, the upper rear transfer device 46 extends long toward the side with a small number of strips, that is, toward the right front.

The upper rear transport device 46 and the vertical transport device 45 are rotated downward when the harvested rice, wheat or the like has a short culm length (hereinafter referred to as a short culm), and moved to the deepest position in the downward rotation. , The front end of the trajectory of the tine 46a of the upper rear transfer device 46 and the line connecting the star wheel 40 and the rear end of the scraping belt 41 are configured to wrap in a side view. When the harvested rice, wheat or the like has a long culm length (hereinafter referred to as a long culm), it is rotated upward, and at the shallowest position in the upward rotation, the front end of the tine trajectory of the upper rear transfer device 46 is rotated. And the raising case 35 are wrapped in a side view.

As shown in FIGS. 3 and 4, a transfer portion between the raising case 35 and the upper transfer device 46, that is, a position behind the center raising case 35, is provided at the transfer portion. 50 are provided. The transfer device 50
Are fixed to the center of the plate on the drive shaft 50a and pivotally support the plurality of inherited transfer tines 50b at equal intervals, and are illustrated on a cover that covers the inherited transfer tines 50b. , And the bases of the inherited transfer tines 50b, 50b,... Are guided by the guides, protrude to the right in the traveling direction, that is, to the single-cutting side, and are stored in the cover on the left. I have. In the present invention, three inherited transfer tines 50 are provided around the drive shaft 50a.
b, 50b and 50b are provided. A flat gear 51, which is a driven gear, is fixedly provided at the lower end of the drive shaft 50a. On the other hand, among the star wheels 40, 40, 40, a drive shaft 40a extending upward is fixed to the star wheel 40 positioned at the center in the lateral direction of the fuselage, and is fixed to the upper end of the drive shaft 40a. The flat gear 40b and the flat gear 51 disposed at the lower end of the drive shaft 50a are configured to mesh with each other.

In this way, the drive from the engine 16 given to the star wheel 40 is transferred to the transfer device 5 via the drive shaft 40a, the spur gears 40b and 51 and the drive shaft 50a.
0, the pair of flat gears 40b
It is possible to increase the rotation speed of the inherited transfer device 50 by adjusting the gear ratio of 51,
It is possible to easily increase the rotation speed of 50b and 50b, and it is possible to eliminate stagnation of the culm due to insufficient feeding ability even when the engine 16 is rotating at low speed.

As shown in FIG. 4, a transport guide 47 extends rearward from the right raising case 35 to a front position of the upper rear transport device 46. The transport guide 4
7 passes above the scraping belt 41 and is disposed at a front position with the front end of the trajectory of the tine 46a of the upper rear transfer device 46. The tine 46a of the upper rear transfer device 46 It is configured to protrude from the rear position so as not to hit, so that the cereal stem guided by the transport guide 47 can be pinched from the rear portion. As a result, the grain stem raised and cut by the tine 36 of the right raising case 35 is conveyed to the right scraping belt 41 and inherited by the upper rear conveying device 46 at the rear thereof. Since the transport guide 47 and the inherited transport device 50 inherit the grain culm to the position of the tine locus of the upper rear transport device 46 without disturbing the culm at the joint portion, stable transport can be performed with a simple configuration and at low cost. . In addition, by disposing the transport guide 47, the projecting start position of the tines 46a of the upper rear transport device 46 is set slightly rearward as compared with the conventional case, and interference with the transport guide 47 is prevented.

Next, the drive transmission structure of the cutting blade 74 is shown in FIG.
This will be described with reference to FIGS. As shown in FIGS. 5 and 6, a bevel gear case 81 provided at the right end of the horizontal pipe 30 is provided.
The drive pulley shaft 70 orthogonal to the cutting triaxial shaft 30a is further extended upward from the right outside of the right raising drive orthogonal shaft 82 in FIG.
a from the bevel gear fixed to the right end of
Power is transmitted via a bevel gear 70b provided at the lower end of the zero. The drive pulley shaft 70 extends upward, and a drive pulley 70a is disposed slightly below the upper end thereof.

As shown in FIG. 7, the drive pulley 70a is composed of a split pulley including a sliding portion 70U and a fixed portion 70D. The fixed portion 70D is fixed on the drive pulley shaft 70, A sliding portion 70U is provided above the driving pulley shaft 7.
The drive pulley shaft 70 is supported so as to be slidable in the axial direction 0 and rotate integrally with the drive pulley shaft 70. In this embodiment, the sliding portion 70U is spline-fitted to the drive pulley shaft 70. As shown in FIG. 7, a spring groove 60d is provided on the upper surface of the fixed portion 70D in a substantially circumferential shape, and the sliding portion 70U
A spring groove 60u is provided in a substantially circumferential shape on the lower surface of the spring, and both spring grooves 60d and 60u are aligned from above and below, and a compression spring 61 is inserted into the inside thereof to slide the sliding portion 70U upward. It is energizing. An endless belt 78 is wound around the driving pulley 70a. In this embodiment, a V-belt is used as an endless body.

The belt 78 is wound so as to be inclined slightly downward toward the front, and its front end is wound around a driven pulley 72a, which is substantially parallel to the drive pulley shaft 70. The driven pulley shaft 72 provided
It is fixed on top. Further, a tension pulley 71a is provided near an intermediate position between the driven pulley 72a and the driving pulley 70a so as to apply an appropriate tension to the belt 78 wound around the driving pulley 70a and the driven pulley 72a. Make up. Then, the driving pulley 70a,
Tension pulley 71a, driven pulley 72a, belt 7
A belt cover 77 is disposed so as to cover the belt 8 from above, so that dust, dirt and the like do not adhere to the driving portion such as the belt 78.

The drive pulley shaft 70 projects further upward than the belt cover 77, and cams 63D and 63U are slidable in the axial direction of the drive pulley shaft 70 at the upper end thereof. On the other hand, it is rotatably supported. The cams 63D and 63U are formed by dividing a columnar shape pulled out by the drive pulley shaft 70 into two at the top and bottom, and the cut surfaces thereof are inclined. It is configured not to rotate independently. A retaining ring 64 is fixedly mounted on the drive pulley shaft 70 above the cam 63U.
The thrust bearing 62 is disposed between the lower surface of the cam 63D and the sliding portion 70U of the driving pulley 70a, and the cam 63D is moved by the elastic force of the compression spring 61. Pressing upward.

Further, one cam 63U (or cam 6
The rotating arm 65 fixed to 3D) is driven by a driving pulley shaft 70.
Extends vertically and has a link 66 at its end.
Is rotatably supported. The link 66 extends rearward of the fuselage and has a speed adjusting arm 67 at its end.
Rotatably supported by the rotary arm 65 and the link 6
6 and the speed adjusting arm 67 are disposed substantially in the same plane. The other cam 63D is fixed to the cutting frame side. The speed adjusting arm 67 is rotated by receiving a driving force from an actuator such as a motor, a solenoid, or a cylinder (not shown), and forms a continuously variable transmission mechanism 68 together with the cams 63U and 63D. However, the sliding part 70U
May be directly slidably driven by an actuator.

Then, the speed adjusting arm 67 rotates in the direction of arrow A in FIG. 8 by the driving force from the actuator, and the rotating arm 65 rotates in the direction of arrow B via the link 66. The rotation of the rotation arm 65 also causes the cam 63U to rotate in the direction of arrow B. However, since the cut surfaces of the cam 63U and the cam 63D are inclined as described above, the cam 63U whose upward movement is restricted. Presses the cam 63D downward. Thereby, the thrust bearing 62
The sliding portion 70U of the drive pulley 70a is pressed downward via the, so that the sliding portion 70U moves downward to a position where the elastic force of the compression spring 61 and the equilibrium state are maintained. This sliding part 70U
As a result, the belt 78 moves to the outer peripheral side of the driving pulley 70a and the speed of the driven pulley 72a can be increased.

The split pulley-type continuously variable transmission mechanism 68 is configured as described above, and adjusts the position of the sliding portion 70U.
By changing the distance between U and the fixed portion 70D, the radius of the driving pulley 70a with which the belt 78 contacts is increased or decreased, and a rotational speed difference is generated between the driving pulley 70a and the driven pulley 72a in a stepless manner. In this embodiment, the drive pulley 70a is used as a split pulley to perform a continuously variable transmission. However, the driven pulley 72a may be used as a split pulley to perform a continuously variable transmission. In addition, both pulleys 70a and 72a
Can be used as a split pulley to perform a continuously variable transmission. In this case, a larger transmission can be obtained.

On the other hand, a crank plate 72b is fixed to the lower end of the driven pulley shaft 72. The crank plate 72b has a substantially rectangular shape and extends in a direction orthogonal to the driven pulley shaft 72.
c is projected. The crankshaft 72c is substantially parallel to the driven pulley shaft 72 and protrudes downward, and its lower end protrudes from above into a substantially rectangular crank groove 73a provided in the knife head 73. Thus, the crank mechanism is configured. As shown in FIG. 7, the knife head 73 has a substantially trapezoidal shape, and is provided with a crank groove 73c from the rear to the center. Cutting blade 74 is mounted.

The cutting blade 74 is disposed below the knife head 73 in the lateral direction of the machine body. The cutting blade 74 is integrally formed with the knife head 73 by bolts and the like. A receiving blade 75 is disposed below the cutting blade 74 in the left-right direction of the machine body, and the receiving blade 75 and the cutting blade 74 reciprocating in the left-right direction above the receiving blade 75 are used for stocks such as rice and wheat. Disconnect.

In the drive transmission configuration of the cutting blade 74 configured as described above, the driving force of the engine 16 is transmitted to the drive pulley shaft 70 via the transmission one shaft 19, the transmission two shaft 25a, and the cutting three shaft 30a. . The rotational driving force of the driving pulley 70a is transmitted to a driven pulley 72a via a belt 78, and a crank plate 72b and a crank shaft 72c fixed to the lower end of the driven pulley shaft 72 of the driven pulley 72a.
Is driven to rotate about the driven pulley shaft 72. As a result, the crankshaft 72c makes a circular motion around the driven pulley shaft 72. Since the lower end of the crankshaft 72c is inserted into the crank groove 73a of the knife head 73 as described above, the circular motion of the crankshaft 72c is made. Tries to push the inner wall of the crank groove 73a in the rotation direction. However, since the knife head 73 is integrally fixed to the lower cutting blade 74, and the cutting blade 74 is supported so as to be slidable only in the left-right direction of the machine body, the circular motion of the crankshaft 72c is changed in the left-right direction. This is converted into a reciprocating motion, and the cutting blade 74 reciprocates in the left-right direction integrally with the knife head 73.

Since the driving of the cutting blade 74 is synchronized with the traveling speed, when the traveling speed is low, the cutting blade 74 is driven.
The cutting speed (the reciprocating speed of the cutting blade 74) is reduced.
Therefore, the drive pulley 70 is driven by the continuously variable transmission mechanism 68 described above.
The rotational speed of the driven pulley 72a is increased or decreased by adjusting the radius of the driven pulley 72a with respect to the belt 78. Thus, the cutting performance of the culm can be improved by increasing the driving speed of the cutting blade 74 even when the engine 16 is rotating at a low speed. Also, the cutting blade 7 is controlled by the continuously variable
Since the drive speed of the drive gear 4 can be changed steplessly, clogging of the culm can be prevented by a smooth gear change operation, and
It is also possible to reduce the impact on components such as 4.

As shown in FIG. 9, a cutting position sensor 91, a vehicle speed sensor 92, a cutting switch 93 and an actuator 94 are connected to a controller 90, and the cutting blade drive speed is calculated from the output value calculated by the controller 90. It is configured to adjust. First, when a command to start the mowing drive is input from the mowing switch 93, the controller 90 determines whether or not the mowing drive can be started based on the input value of the mowing position sensor 91. If the reaping position is in the reaping-possible state (that is, the reaping position is not at the highest position), the controller 90 outputs a command to start the reaping drive.

The controller 90, which has output the command to start the cutting drive, subsequently detects the vehicle speed 98 from the vehicle speed sensor 92, and drives the cutting blade so that the relationship between the vehicle speed 98 and the cutting blade driving speed 99 becomes a curve 96 in FIG. The value of the speed 99 is output to the actuator 94. (In FIGS. 10 and 11, the vehicle speed 98 rises rightward with the left end set to 0, and the cutting blade drive speed 99 rises upward with the lower end set to 0.) The rotational displacement of the pulley 67 is adjusted, and the driving pulley 70 a as a split pulley is
Is controlled with respect to the belt 78. As a result, the cutting blade drive speed 99 at a low vehicle speed is higher than the straight line 95 indicating the proportional relationship with the conventional vehicle speed 98, and the cutting performance is improved. Then, as the vehicle speed 98 increases, the vehicle speed 98 approaches a straight line 95 which is the relationship between the conventional vehicle speed 98 and the cutting blade drive speed 99.

As shown in FIG. 11, if the cutting blade driving speed 99 at a low vehicle speed is set to be increased at a stretch, a stable cutting blade driving speed 99 can be obtained immediately after the start of the work, and the remaining cutting of the culm can be obtained. Can be solved.

As shown in FIG. 6, the position of the drive pulley shaft 70 is raised and the drive pulley shaft 70
Although it is configured to be on the outside of the fuselage, similarly, it is raised on the left side of the fuselage and the belt drive unit is arranged outside the orthogonal axis,
It is also possible to adopt a configuration in which a continuously variable transmission mechanism is provided in the belt driving unit, and the same effect as the above-described configuration can be obtained.

As described above, the reaping and transporting steps in the transporting section 10 are as follows. First, at the front end of the reaping section 6, the weeds 34, 34,. Cereal stems, etc., each raised case 35
Are held by the tines 36 and are transported upward. When the root portion reaches the position of the cutting blade 74, the root is cut off by the reciprocating movement of the cutting blade 74 and the receiving blade 75 disposed at the lower portion, and the cut culm is transferred to the transport unit 10 Reach Then, the cereal stem is conveyed backward by the stock origin conveyance unit 42L / 42R,
The upper part is the upper transfer device 43L and the upper rear transfer device 4
6, and the spike portion is conveyed by the front spike conveying device 44L.

In this manner, the stock transfer device 42L / 4
The root side of the cereal stem transported by the 2R is a vertical transport device 45
The upper transfer device 43L and the upper rear transfer device 4
6. The spike side conveyed by the front spike conveying devices 44L and 44R is inherited by the upper rear conveying device 46, and the root side of the grain culm is further inherited by the feed chain 8 and conveyed to the threshing unit 7. ing.

[0038]

As described above, the present invention has the following advantages. That is, a driven pulley is disposed above the cutting blade, the cutting blade can be driven to reciprocate from the driven pulley via a crank mechanism, and a belt is provided between the driven pulley and a driving pulley provided on the cutting frame. Is a combine configured to drive the cutting blade by a belt transmission mechanism, wherein one or both of the drive pulley and the driven pulley are configured by split pulleys,
A split pulley type continuously variable transmission mechanism is configured, and the cutting blade drive speed can be changed by the continuously variable transmission mechanism. By adjusting the radius of the split pulley with respect to the belt, the rotation speed of the driven pulley can be increased or decreased. It is possible to improve the cutting performance of the culm by increasing the driving speed of the cutting blade even at low speed running, and to surely cut off the root of the stock and prevent clogging and the like. In addition, since the driving speed of the cutting blade can be changed steplessly, clogging of the culm can be prevented by a smooth shifting operation, and the impact on components such as the cutting blade can be reduced.

The split pulley comprises a fixed portion fixed to the drive shaft and a sliding portion slidable in the axial direction of the drive shaft and rotating integrally with the drive shaft. The part was slid by the cam, so the radius to the belt was adjusted with a simple configuration,
A continuously variable transmission mechanism has been realized. With a simple configuration, the rotational motion of the cam can be converted into the sliding motion of the split pulley, and a low-cost and stable continuously variable transmission mechanism can be realized.

Further, the sliding portion is driven by an actuator, the actuator and a vehicle speed sensor are connected to a controller, and the driving speed of the cutting blade is controlled to be increased during low-speed running, so that the cutting drive speed is synchronized with the running speed. In the combine configured as above, even at low speed running
The mowing drive speed can be controlled to be substantially constant, and the cutting performance during low-speed running does not decrease. is there.

[Brief description of the drawings]

FIG. 1 is an overall side view of a combine equipped with a mowing device of the present invention.

FIG. 2 is an overall plan view of a combine equipped with the mowing device of the present invention.

FIG. 3 is a side view of the reaper.

FIG. 4 is a plan view of the reaper.

FIG. 5 is a side sectional view of a belt driving unit according to the present invention.

FIG. 6 is a plan view of the belt driving unit of the present invention.

FIG. 7 is a side sectional view showing a continuously variable transmission mechanism of the present invention.

FIG. 8 is a plan view showing a continuously variable transmission according to the present invention.

FIG. 9 is an input / output diagram showing a control structure of a cutting blade drive speed.

FIG. 10 is a diagram showing a relationship between a vehicle speed and a cutting blade drive speed.

FIG. 11 is a diagram showing a relationship between a vehicle speed and a cutting blade drive speed.

FIG. 12 is a skeleton diagram showing a drive transmission system of the mowing unit according to the present invention.

[Explanation of symbols]

 6 Cutting part 61 Compression spring 62 Thrust bearing 63U Cam 63D Cam 64 Retaining ring 65 Rotating arm 66 Link 67 Speed adjusting arm 68 Continuously variable transmission mechanism 70 Driving pulley shaft 70a Driving pulley 70U (Driving pulley) Sliding part 70D (Driving pulley) ) Fixed portion 71a Tension pulley 72 Followed pulley shaft 72a Followed pulley

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2B076 AA03 CC02 DA06 DB02 DB08 EC09 ED30 2B382 GA09 GB01 GC03 GC04 GC13 GC14 GC15 GC22 GC23 GD02 HA02 HA12 HB02 HC03 HC33 HH22 HH50 LA22 MA38

Claims (3)

[Claims] A driven pulley is disposed above a cutting blade. The driven pulley can reciprocally drive the cutting blade via a crank mechanism, and the driven pulley and a driving pulley provided on a cutting frame can be driven by the driven pulley. A combine belt configured to drive a cutting blade by a belt transmission mechanism by winding a belt between the drive pulley and the driven pulley, or one or both of the drive pulley and the driven pulley by a split pulley. A driving mechanism for a cutting blade, comprising a stepped transmission mechanism, wherein the driving speed of the cutting blade can be changed by the continuously variable transmission mechanism. 2. The split pulley comprises a fixed portion fixed to a drive shaft, and a sliding portion slidable in the axial direction of the drive shaft and rotating integrally with the drive shaft. 2. A driving mechanism for a cutting blade according to claim 1, wherein said portion is slid by a cam. 3. The method according to claim 1, wherein the sliding portion is driven by an actuator,
3. The driving mechanism for a cutting blade according to claim 2, wherein the actuator and the vehicle speed sensor are connected to a controller so as to increase the driving speed of the cutting blade during low-speed running.