JP3784298B2 - Shifting structure of work equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a shift operation structure for a work machine including a continuously variable transmission.
[0002]
[Prior art]
Conventionally, in the shift operation structure for a work machine as described above, the operation tool of the continuously variable transmission is configured to be held by a holding mechanism regardless of the operation position.
[0004]
[Problems to be solved by the invention]
  UpAccording to the prior art described above, it is possible to maintain the continuously variable transmission in a very low speed state, and therefore the occurrence of defective work due to the state in which the work device is driven at a low speed as the vehicle runs at a low speed. Was supposed to be invited.
[0005]
By the way, when the work machine is a harvesting work machine such as a combine harvester or carrot harvester, the harvesting speed (in the case of a combine) or digging speed (carrots) is increased when the harvesting and transporting device, which is an example of the work device, is driven at a low speed. In the case of harvesting machines), and the transfer speed will be significantly reduced, resulting in poor harvesting and poor transport due to them, and when the working machine is a transplanting machine such as a rice transplanter In this case, the driving speed of the planting mechanism installed in the seedling planting device, which is an example of a working device, will be significantly reduced. It was.
[0006]
  The present inventionEyesThe target, FineAn object of the present invention is to prevent the occurrence of work defects caused by maintaining the state where the work device is driven at a slow speed as the vehicle travels at a high speed.
[0007]
[Means for Solving the Problems]
〔Constitution〕
In order to achieve the first and second objects, according to the first aspect of the present invention, the operation tool of the continuously variable transmission is returned to the zero speed position by the return force of the neutral return mechanism in the slow speed region. And a holding mechanism configured to hold at a desired operation position in the speed change area higher than the slow speed area.
[0009]
[Action]
  According to the first aspect of the present invention,Since the continuously variable transmission cannot be maintained in the slow speed state, the work device cannot be maintained in the slow speed driving state, and hence the work failure occurs due to the work device being maintained in the slow speed driving state. Can be avoided in advance.
[0010]
〔effect〕
  Therefore, FineOccurrence of work defects caused by maintaining the state where the work device is driven at a slow speed as the vehicle travels at high speed can be avoided.
[0011]
〔Constitution〕
In order to achieve the second object, in the invention according to claim 2 of the present invention, the operating tool of the continuously variable transmission is returned to the zero speed position by the return force of the neutral return mechanism in the slow speed range, and The speed change region that is higher than the slow speed region can be switched between a slow speed cut state that is held at a desired operation position and a non-slow speed cut state that is held at the desired operation position regardless of the speed change region. Equipped with a holding mechanism.
[0012]
[Action]
According to the second aspect of the present invention, the continuously variable transmission cannot be maintained in the slow speed state by switching the holding mechanism to the slow speed cut state during the work travel for driving the work device. Can no longer be maintained in the slow speed driving state, so that it is possible to avoid the occurrence of work defects due to the work device being maintained in the slow speed driving state.
[0013]
In addition, when traveling and traveling over a kite, etc., the continuously variable transmission can be maintained at a very low speed by switching the holding mechanism to the non-slow cut state. It becomes possible to perform with good stability at a low speed.
[0014]
〔effect〕
Accordingly, it is possible to avoid the occurrence of defective work caused by maintaining the state in which the work device is driven at a slow speed with the slow speed travel, and to perform the over-the-wheel travel with high stability.
[0015]
〔Constitution〕
In the invention according to claim 3 of the present invention, in the invention according to claim 2, the slow cut state is realized in association with the operation of engaging the work clutch for intermittently transmitting power to the work device. And the non-slow cut state is displayed in conjunction with the disengagement operation of the work clutch.
[0016]
[Action]
According to the third aspect of the present invention, the holding mechanism can be switched to the slow-cut state without performing the manual operation of the holding mechanism by performing the operation of engaging the work clutch during the work traveling for driving the working device. Therefore, it is possible to avoid the occurrence of work defects due to the work device being maintained in the slow drive state.
[0017]
In addition, when traveling for traveling over a kite, etc., the clutch can be switched to a non-slow cut state without manual operation of the holding mechanism by operating the clutch to disengage the kite. Etc. can be performed with low speed and good stability.
[0018]
〔effect〕
Therefore, while improving the operability, it is possible to avoid the occurrence of work defects caused by maintaining the state in which the work device is driven at a slow speed along with the slow speed travel, and also to improve the stability of traveling over the heel. I was able to do it.
[0019]
〔Constitution〕
According to a fourth aspect of the present invention, in the first aspect of the present invention, the movable body is externally fitted on the support shaft extending from the fixed member so as to be relatively slidable and relatively rotatable. The body is equipped with a first spring that presses the operating tool against the fixed member via a pressing member that is restricted from moving toward the fixed member, and the movable member is interposed between the support shaft and the movable body. A second spring for urging the body in a direction away from the fixing member; and a detachment provided on the anti-fixing member side of the support shaft by the urging of the second spring on the anti-fixing member side of the movable body. A V-groove that separates the pressing member from the operating tool by engagement with a coupling pin is formed, and the movable body has a state in which the center of the engagement pin is located within the groove width of the V-groove in the slow speed region. In cooperation with the operation tool, the holding mechanism has the neutral return mechanism. , In the return force of the neutral return mechanism, wherein the very low speed region is configured such that the operating member is restored to zero speed position.
[0020]
[Action]
According to the fourth aspect of the invention, when the operating tool of the continuously variable transmission is located in the slow speed region including the neutral position, the movable body is moved away from the fixed member by the urging of the second spring. Is allowed to move, and the movable body is engaged with the movable body by rotating the movable body so that the engaging pin is positioned at the bottom of the V-groove with the movement. Thus, the operating tool returns to the zero speed position by the rotation of the movable body.
[0021]
Further, in a state where the operating tool of the continuously variable transmission is located in the speed change region on the higher speed side than the slow speed region, the engaging pin comes out of the V groove of the movable member, and the movable member is attached with the second spring. The operating tool is held at the desired operating position because the operating tool is pressed against the fixing member by the biasing force of the first spring via the pressing member while being positioned on the fixing member side against the force. Will come to be.
[0022]
In other words, the operation tool can be returned to the zero speed position in the slow speed region by the holding mechanism without providing a neutral return mechanism of another configuration, and the desired operation can be performed in the speed change region higher than the slow speed region. Can be held in position.
[0023]
〔effect〕
Therefore, it is possible to avoid the occurrence of work defects caused by maintaining the state in which the work device is driven at a slow speed with the slow speed travel while simplifying the structure and reducing the manufacturing cost.
[0024]
〔Constitution〕
In the invention according to claim 5 of the present invention, in the invention according to claim 2 or 3, the movable body is externally fitted so as to be relatively slidable and relatively rotatable on a support shaft extending from the fixed member. The movable body is equipped with a first spring that presses the operating tool against the fixed member via a pressing member that is restricted from moving toward the fixed member, and between the support shaft and the movable body, A second spring that urges the movable body in a direction away from the fixed member is provided, and is provided on the anti-fixed member side of the movable body on the anti-fixed member side of the support shaft by the urging of the second spring. A V-groove for separating the pressing member from the operating tool by engagement with the engaging pin is formed, and the operating body and the movable body are linked with the operation of the operating tool. In relation to the state of relative rotation with respect to the fixed member, Then, the slow cutting position where the center of the engaging pin is located within the groove width of the V-groove, and the center of the engaging pin deviating from the groove width of the V-groove regardless of the speed change region. The holding mechanism has a neutral return mechanism and can be switched between the slow cut state and the non-slow cut state.
[0025]
[Action]
According to the fifth aspect of the present invention, when the support shaft is positioned at the slow cut position, the operation tool of the continuously variable transmission is movable by the bias of the second spring in a state where the operation tool is located in the slow speed region including the neutral position. The movement of the body in the direction away from the fixing member is allowed, and with the movement, the V groove and the engagement pin of the movable body are in a state where the engagement pin is located at the bottom of the V groove. Then, the movable body is engaged while rotating, and the operation tool returns to the zero speed position by the rotation of the movable body.
[0026]
Further, in a state where the operating tool of the continuously variable transmission is located in the speed change region on the higher speed side than the slow speed region, the engaging pin comes out of the V groove of the movable member, and the movable member is attached with the second spring. The operating tool is held at the desired operating position because the operating tool is pressed against the fixing member by the biasing force of the first spring via the pressing member while being positioned on the fixing member side against the force. Will come to be.
[0027]
On the other hand, when the support shaft is positioned at the non-slow cutting position, the engaging pin comes out of the V-groove of the movable body regardless of the speed change region, and the movable body is fixed against the biasing force of the second spring. Since the operating tool comes into pressure contact with the fixed member by the biasing force of the first spring via the pressing member, the operating tool is held at a desired operating position.
[0028]
In other words, even if no neutral return mechanism or switching mechanism is provided, the holding mechanism returns the operating tool to the zero-speed position in the slow speed region, and the desired operation is performed in the shift region on the higher speed side than the slow speed region. It is possible to switch between the slow cut state held at the position and the non-slow cut state held at the desired operation position regardless of the shift region.
[0029]
〔effect〕
Therefore, while simplifying the structure and reducing the manufacturing cost, it is possible to avoid the occurrence of work defects caused by maintaining the state in which the work device is driven at a slow speed as the vehicle runs at a slow speed. It has become possible to run with good stability.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an overall side view of a self-decomposing combine as an example of a work machine, and FIG. 2 shows an overall plane thereof. The combine includes a traveling machine body having a pair of left and right crawler type traveling devices 1. A harvesting type harvesting and conveying device 3 which is an example of a working device is connected to the left side of the front part 2 so as to be swingable up and down around a horizontal axis, and a control tower 4 and a driving seat are connected to the front right side of the traveling body 2. 5 is formed, and a threshing process, a sorting process, and the like are performed on the harvested cereal meal from the harvesting and transporting device 3 at a position immediately after the harvesting and transporting device 3 and the steering unit 6 in the traveling machine body 2. A threshing device 7 is mounted, and a waste straw cutting device 8 that shreds the waste straw from the threshing device 7 is provided at the left rear portion of the threshing device 7 in the traveling machine body 2, and the right of the threshing device 7 in the traveling machine body 2. In the rear part, from the threshing device 7 through the lifting conveyor 9 It is configured by arranging a bagging apparatus 11 packed in grain bag 10 the kernels are conveyed Te.
[0031]
As shown in FIG. 1, the left and right crawler type traveling device 1 includes a driving wheel 12 disposed at a front portion thereof, an idler wheel 13 disposed at a rear portion thereof so as to be position-adjustable in the front-rear direction, It is constituted by three abduction wheels 14 disposed between the wheel 13 and a crawler belt 15 stretched so as to surround them.
[0032]
As shown in FIGS. 1 and 2, the harvesting and conveying apparatus 3 includes three dividers 16 for scooping up the planted cereals, left and right pulling mechanisms 17 that cause the planted cereals to fall down, and planting rice, wheat, or the like. It is provided with a clipper-shaped cutting mechanism 18 that cuts the stock side of the standing cereal and a transport mechanism 19 that changes the posture from a vertical position to a horizontal position while transporting the harvested cereal backward. It is configured to cut and convey the minute.
[0033]
As shown in FIGS. 3 and 4, the threshing device 7 includes a threshing processing unit 20 in which the threshing processing direction is set in the front-rear direction, a sorting processing unit 21 in which the sorting processing direction is set in the left-right direction, and the collection conveyance direction. Are arranged in the order from the top, and the threshing processing unit 20 arranged at the upper part of the threshing device 7 has a feed chain 23 arranged on the left outer side thereof. By pinching the stock side of the harvested cereal mash from the transport mechanism 19 and transporting it backward, the tip of the chopped cereal grain on the receiving net 25 in the handling chamber 24 formed at the upper left side of the threshing device 7 The handling cylinder 26 installed in the handling chamber 24 in the front-rear direction rotates around its support shaft 27, so that the tip of the harvested cereal rice cake guided onto the receiving net 25 by the feed chain 23 is moved to the tip side. It is comprised so that a threshing process may be performed with respect to it.
[0034]
In the sorting processing unit 21 provided in the upper and lower intermediate part of the threshing device 7, the swing sorting mechanism 28 disposed below the receiving net 25 is driven to swing in the left-right direction by the rotation of the front-rear drive shaft 29. Thus, the threshing processed product leaking from the receiving net 25 with the threshing processing and the threshing processed product released from the dust feed port 30 formed at the lower end of the handling room 24 in the threshing processing direction are selected. While moving toward the lower right side of the processing direction, the screen is subjected to a sieve selection process for sieving into grains, straw scraps, sliced straws, etc. according to the difference in size, and left and right in the lower left of the handling cylinder 26 The tang 31 deployed on the rotating shaft 32 rotates around the support shaft 32 to generate the sorting wind, and the sorting wind is formed at the right end of the threshing device 7 on the lower side of the sorting process direction from the tang 31. By making the inside of the sorting air passage 34 over the dust outlet 33 flow, the sorting wind The threshing treated supplied into the 34, and is configured to perform a like and the Fukiwakeru wind distinguishing processing grain and straw waste and broken straw by differences in specific gravity.
[0035]
The recovery unit 22 arranged at the lower part of the threshing device 7 is configured so that the first screw 35 disposed on the upper side in the sorting process direction below the swing sorting mechanism 28 rotates around the support shaft 36, thereby swinging. The grain that has leaked from the grain sieve 37 arranged on the upper side of the sorting process direction of the dynamic sorting mechanism 28 and has passed through the sorting air passage 34 is conveyed toward the lifting conveyor 9 as the first thing, and is shaken. The second screw 38 disposed on the lower side in the sorting process direction below the dynamic sorting mechanism 28 rotates around its support shaft 39, so that the straw disposed on the lower side in the sorting process direction of the swing sorting mechanism 28. A mixture of grains and straw scraps that have leaked from the rack 40 and passed through the sorting air passage 34 is transported as a second product toward the thrower-type reduction transport mechanism 41, Blade 42 is No. 2 screw 8 and that rotate integrally, and is configured to re-process by reducing the number 2 was the threshing chamber 24.
[0036]
Among the threshing products, the cut straw that has been transported to the rear end of the oscillating sorting mechanism 28 without leaking from the Strollac 40 of the oscillating sorting mechanism 28, or on the lower side of the sorting process direction on the sorting wind. The dust such as straw scraps blown up is discharged from the dust outlet 33 as the third item.
[0037]
Although not shown in the drawings, the waste blower cutting device 8 is a so-called cylinder-type cutter that folds the waste straw transported in the left-right orientation by the feed chain 23 into a pine needle-like fold and chops in order from the refracting end. As a result, compared with a case where a disc-shaped cutter that receives the waste straw in the left-right orientation as it is and chops it with a plurality of discs is adopted, the waste straw cutting device 8 is located behind the threshing device 7. The left and right length of the arrangement space required for the arrangement can be greatly reduced, and as a result, the arrangement space for the bagging device 11 can be secured on the right side thereof.
[0038]
As shown in FIG. 1 and FIG. 2, in the bag filling device 11, the grain conveyed by the lifting conveyor 9 is guided and supplied into the left and right grain bags 10 via the left and right bifurcated discharge cylinders 43. A two-bag type is adopted, and the bag-packing work efficiency can be improved as compared with the case where a one-bag type is adopted.
[0039]
In other words, immediately after the harvesting and conveying apparatus 3 and the control unit 6 arranged side by side in the left-right direction, a swing sorting mechanism 28 that is longer than the handling cylinder 26 so that the threshing process direction and the sorting process direction are orthogonal to each other. A threshing device 7 whose length in the front-rear direction is significantly shortened by being arranged in the left-right direction is disposed immediately after the threshing device 7, and a waste straw cutting device 8 that saves space, and a bagging work efficiency. By arranging the two-bag type bag filling device 11 in parallel in the left-right direction, the swing sorting mechanism 28 can be arranged in the front-rear direction without causing a reduction in work capacity. Compared to the case where the waste straw cutting device 8 and the bagging device 11 are arranged side by side on the left and right sides of the longer threshing device 7, the longitudinal length of the traveling machine body 2 on which they are mounted is set. As a result, it is possible to shorten the weight and reduce the weight. It becomes possible to effectively reduce the overall size and weight of the combine, and it can be loaded on a light truck bed even though it is a passenger type equipped with a control unit 6. Even in fields such as mountainous areas where the combine cannot be transported, it is possible to use a ride-type combine having a high work capacity.
[0040]
As shown in FIGS. 1, 2, and 4, an engine 44 is mounted below the driver seat 5, and power from the engine 44 is transmitted to the continuously variable transmission via a belt tension type main clutch 45. It is transmitted to a hydrostatic continuously variable transmission 46 which is an example, transmitted to a threshing device 7 via a belt-type transmission mechanism 47 which also serves as a work clutch, and is connected to the harvesting and conveying device 3 via a belt tension type lifting clutch 48. It is configured to be transmitted to a screw feed type lifting device 49 that moves up and down.
[0041]
As shown in FIGS. 4 to 6, in the elevating device 49, the power from the engine 44 is transmitted to the screw shaft 50 provided on the traveling machine body 2 side via the elevating clutch 48, and the screw shaft 50 is rotated forward by the power. Then, the cylindrical female screw member 51 provided on the harvesting and conveying apparatus 3 side is screwed to the harvesting and conveying apparatus 3 side, whereby the harvesting and conveying apparatus 3 is raised, and the lift clutch 48 is used for the engine. In the state where the transmission of power from 44 to the screw shaft 50 is cut off, the braking arm 53 performs a braking action on the output pulley 52 of the elevating clutch 48, and the rotation of the screw shaft 50 is prevented. The apparatus 3 is lifted and stopped at a desired height position, and further, the transmission of power from the engine 44 to the screw shaft 50 is cut off by the lifting clutch 48, and the braking arm 53 with respect to the output pulley 52 is The operation is released, the screw shaft 50 is reversed by the weight of the harvesting and conveying apparatus 3, and the harvesting and conveying apparatus 3 is lowered by screw feeding the female screw member 51 to the traveling machine body 2 side. .
[0042]
The lead angle of the screw shaft 50 and the female screw member 51 is set to a large angle that allows the screw shaft 50 to be reversed by the weight of the harvesting and conveying device 3.
[0043]
The elevating clutch 48 is urged to return to a cut-off state in which the transmission of power from the engine 44 to the screw shaft 50 is cut off by a first spring 55 installed over the traveling machine body 2 and the tension arm 54.
[0044]
The braking arm 53 can contact the output pulley 52 from the lower side in the rotation direction when the output pulley 52 is rotated in reverse by the weight of the harvesting conveyance device 3 in a tension posture in which the output pulley 52 bites into the output pulley 52 by the rotation. In this manner, the output pulley 52 is urged to be joined by a second spring 56 installed over the traveling machine body 2 and the braking arm 53.
[0045]
The traveling machine body 2 is provided with a linkage arm 58 installed between the linkage pin 57 provided in the harvesting conveyance device 3 and the tension arm 54 of the lifting clutch 48 so as to be swingable around the support shaft 59. The arm 58 is configured to switch the lifting clutch 48 from the transmission state to the cutoff state by operating the tension arm 54 in conjunction with reaching the upper limit position of the harvesting conveyance device 3.
[0046]
That is, ascending the harvesting and conveying apparatus 3 can be automatically stopped as the harvesting and conveying apparatus 3 reaches the upper limit position.
[0047]
As shown in FIGS. 7 to 11, the motive power transmitted to the hydrostatic continuously variable transmission 46 is transmitted through a gear-type transmission 61 provided in the transmission case 60 and left and right side clutch brakes 62. Are transmitted to the corresponding crawler type traveling device 1, and are transmitted to the harvesting and conveying device 3 via the gear type transmission 61 and the harvesting clutch 63 which is an example of a work clutch. .
[0048]
The gear-type transmission 61 is configured to shift the power after shifting by the hydrostatic continuously variable transmission 46 to two levels.
[0049]
The configuration of the gear transmission 61 will be described in detail. The gear transmission 61 includes a low-speed first transmission shaft 65 to which power after transmission by the hydrostatic continuously variable transmission 46 is transmitted via a bevel gear 64. The first drive gear 66 and the second drive gear 67 for high speed are equipped so as to rotate integrally around the axis and slide integrally along the axis, and the transmission shaft is provided by the ball detent mechanism 68. 65 is configured so that the position can be switched between a low-speed forward position for work (see FIGS. 7 to 9), a high-speed forward position for movement (see FIG. 10), and a low-speed backward position for movement (see FIG. 11). ing.
[0050]
As shown in FIGS. 7 to 9, at the low-speed forward position for work, the first drive gear 66 is the low-speed first in the traveling relay gear 70 loosely fitted to the support shaft 69 of the left and right side clutch brakes 62. The first driven gear portion 71 meshes with the work output gear 73 equipped to rotate integrally with the work output shaft 72, and the second drive gear 67 is connected to the high speed relay gear 70 for traveling. The engagement with the second driven gear portion 74 is released.
[0051]
As shown in FIG. 10, at the high speed forward position for movement, the first drive gear 66 releases the mesh with the first driven gear portion 71 for low speed and the output gear 73 for work, and the second drive gear 67. However, it meshes with the second driven gear portion 74 for high speed.
[0052]
As shown in FIG. 11, in the low speed reverse position for movement, the first drive gear 66 is engaged with the first driven gear portion 71 for low speed while being disengaged from the output gear 73 for work. The two drive gear 67 releases the mesh with the second driven gear portion 74 for high speed.
[0053]
That is, the sliding operation of the transmission shaft 65 configured to function as a moving member without providing a dedicated moving member for shifting the gear-type transmission 61 or switching the transmission state to the harvesting conveyance device 3. Therefore, the gear type transmission 61 can be changed and the harvesting and conveying device 3 can be switched between the driving state and the stopping state, thereby improving the operability while simplifying the structure and reducing the manufacturing cost. It can be planned.
[0054]
As shown in FIGS. 8 to 11, the ball detent mechanism 68 is integrated with the transmission shaft 65 and is urged by a spring 75 so as to protrude from the peripheral surface of the ball detent mechanism 68. The transmission shaft 65 is fitted from a cylindrical boss 78 having three ring-shaped recesses 77 formed on the fitting surface with the transmission shaft 65 and allowing the balls 76 to be engaged with each other. The ball detent mechanism 68 is configured so as to be held at a desired speed change position, so that the ball 76 urged by the spring 75 toward the transmission shaft 65 is provided on the boss 78 side. It can be configured as a compact one with a small outer diameter, and a small diameter bearing 79 can be employed as the bearing 79 for externally fitting and supporting the boss 78. Furthermore, the transmission shaft 65 and the transmission cable can be used. 60 in comparison with the case of constituting a ball detent mechanism 68 between, and is capable of rotating the transmission shaft 65 to the resistance less smoothly.
[0055]
As shown in FIGS. 7 and 9 to 11, the left and right side clutch brakes 62 each include a movable member 80 that is loosely fitted to a support shaft 69 so that its meshing transmission portion 81 is included in the relay gear 70. While engaging with the fitting transmission portion 82, the engagement portion 83 is slid to the transmission position for releasing the engagement with the engagement pin 84 mounted on the transmission case 60, so that the gear-type transmission 61 A transmission state (see FIG. 7 and FIG. 9) in which the power after the shift is transmitted to the corresponding crawler type traveling device 1 via the transmission gear 85 meshed with the meshing transmission portion 81 appears, and the movable member 80, a non-transmission position where the meshing transmission part 81 releases the meshing with the internal fitting transmission part 82 of the relay gear 70 and the locking part 83 releases the locking with the locking pin 84 of the transmission case 60. By sliding the A shut-off state (see the right side clutch brake 62 in FIG. 10) in which the power after the shift by the device 61 is not transmitted to the corresponding crawler type traveling device 1 appears, and the movable member 80 has its meshing transmission portion 81 While the meshing of the relay gear 70 with the internally fitted transmission portion 82 is released, the locking portion 83 is slid to the braking position where the locking pin 84 of the transmission case 60 is locked, so that the corresponding crawler type A braking state (see the right side clutch brake 62 in FIG. 11) in which the traveling device 1 is braked and stopped appears.
[0056]
As shown in FIGS. 1, 2, 5 to 7, and 12 to 16, the control tower 4 is configured to be capable of cross-swinging around a left and right support shaft 86 and a front and rear support shaft 87. The control lever 88 is connected to the lifting device 49 via the first linkage mechanism 89 and linked to the left and right side clutch brakes 62 via the second linkage mechanism 90. .
[0057]
The first linkage mechanism 89 includes a first balance arm 91 that moves forward and backward integrally around a control lever 88 and a left and right support shaft 86, and a first linkage wire 92 that extends from the rear end of the first balance arm 91 to the braking arm 53. In addition, the second linkage wire 93 extending from the front end of the first balance arm 91 to the tension arm 54, etc. is used to perform braking by biasing the second spring 56 in conjunction with the operation of the control lever 88 to the neutral position in the front-rear center. The contact of the arm 53 with the output pulley 52 is permitted, the swinging operation of the tension arm 54 to the blocking position by the biasing of the first spring 55 is permitted, and the control lever 88 is moved to the forward lowered position. In conjunction with the operation, the braking arm 53 is separated from the output pulley 52 against the bias of the second spring 56, and conversely, in conjunction with the operation of the control lever 88 to the rearward raised position, the first bar It is configured to swing operating the tension arm 54 to the transmission position against the 55 biases the.
[0058]
The second linkage mechanism 90 is integrally pivoted about the control lever 88 and the second balance arm 94 facing left and right integrally swinging around the support shaft 87 facing forward and backward, and the corresponding operating arm 95 and support shaft 96 of the side clutch brake 62. The left and right crank arms 97 that move, and the left and right third linkage wires 98 that extend from the left and right ends of the second balance arm 94 to the corresponding crank arms 97, etc. The left and right side clutch brakes 62 are allowed to appear in the transmission state due to the urging of the spring 99, and in conjunction with the operation from the neutral position of the control lever 88 to either the left or right gentle turning position, The corresponding side clutch brake 62 is turned off against the bias of the spring 99, and the steering lever 88 is turned from the left or right gentle turning position to the sudden turning position. In conjunction with the operation, it is configured to emerge the braking state of the steering clutch brake 62 corresponding against the bias of the spring 99.
[0059]
That is, when the control lever 88 is operated to the neutral position, the harvesting and conveying device 3 can be lifted and stopped, and the straight traveling state in which the left and right crawler type traveling devices 1 are driven at a constant speed can be displayed. When the lever 88 is operated to the front lowering position, the harvesting and conveying apparatus 3 can be lowered by its own weight. Conversely, when the control lever 88 is operated to the rearward raising position, the harvesting and conveying apparatus 3 is raised by the power from the engine 44. On the other hand, when the control lever 88 is operated to either the left or right gentle turning position, one of the crawler type traveling devices 1 corresponding to the operation direction is idled and the other crawler type traveling device 1 is driven. A slow turning state can be revealed, and when the control lever 88 is operated to either the left or right sudden turning position, one crawler type corresponding to the operating direction And it is capable of revealing the abrupt turning state along with braking the line device 1 drives the other crawler type traveling device 1.
[0060]
As shown in FIGS. 12 to 15 and 17, the longitudinal support shaft 87 is bent so that the rear end portion is directed leftward, and the rear end portion is loosely fitted to the left and right support shaft 86. It is clamped by a pair of upper and lower clamping members 101 that are clamped and urged by the clamping spring 100, and by this clamping action, the control lever 88 can be returned to the neutral position in the front-rear direction and the left-right direction.
[0061]
That is, since it is not necessary to provide a dedicated return mechanism for returning the control lever 88 to the neutral position in the front-rear direction and a dedicated return mechanism for returning to the neutral position in the left-right direction, Manufacturing costs can be reduced.
[0062]
As shown in FIGS. 7, 16, and 18 to 20, the left and right side clutch brakes 62 include an operation arm 95, left and right crank arms 97 that swing integrally around a support shaft 96, and a third linkage mechanism 102. Via the operation pedal 103 provided in the control unit 6.
[0063]
The third linkage mechanism 102 includes a support shaft 104 that supports the swingable pedal 96 by stepping on the operation pedal 103, a balance arm 105 that is swingably supported by the right support shaft 96, and the support shaft 104 and the balance arm 105. The linkage pins 107 mounted on the balance arm 105 press and operate both the left and right crank arms 97 when the operation pedal 103 is stepped on by the linkage springs 106, etc., and the left and right side clutch brakes 62. The shut-off state and the braking state are displayed.
[0064]
Further, the control unit 6 is engaged with an engagement pin 108 provided on the operation pedal 103 to hold the operation pedal 103 in the depressed position and maintain the left and right side clutch brakes 62 in a braking state. 109 is equipped.
[0065]
In other words, the left and right side clutch brakes 62 can be used both as a travel brake and a parking brake, so that the configuration can be simplified and the manufacturing cost can be reduced as compared with the case where the travel brake and the parking brake are equipped. It is like that. In addition, a simple operation of simply depressing the operation pedal 103 has an advantage that a state in which the harvesting and conveying apparatus 3 is driven at a constant speed while stopping the traveling of the machine body can be realized. Moreover, since the transmission to the left and right crawler type traveling devices 1 is cut off in the braking state, it is possible to avoid the occurrence of inconvenience that the hydrostatic continuously variable transmission 46 and the left and right side clutch brakes 62 interfere with each other. Accordingly, as shown in FIG. 21, even if the left and right side clutch brakes 62 are provided with the friction brake 110, the hydrostatic continuously variable transmission 46 and the left and right side clutch brakes 62 interfere with each other. It is possible to prevent the brake disc from being seized due to the above.
[0066]
As shown in FIGS. 7, 16, 18, and 19, the left and right side clutch brakes 62 include left and right crank arms 97 that swing integrally around the operation arm 95, the support shaft 96, and the fourth linkage mechanism 111. Accordingly, the operation pedal 103 is linked to an operation lever 113 supported so as to be swingable integrally around the support shaft 104 and relative to the support shaft 112 in the vertical direction.
[0067]
The fourth linkage mechanism 111 includes a balance arm 114 that swings integrally around the operation lever 113 and the support shaft 112, and one linkage wire 115 that extends from both ends of the balance arm 114 to the corresponding crank arm 97. In conjunction with the swinging operation in the direction, the side clutch brake 62 corresponding to the operation direction is switched to the transmission state, the cutoff state, and the braking state according to the operation position.
[0068]
That is, even from the dismounting position, by swinging the operation lever 113 left and right, the left and right crawler type traveling devices 1 are driven straight at a constant speed, and either the left or right crawler type traveling device 1 is idled. Switching between a slow turning state in which the other crawler type traveling device 1 is driven and a sudden turning state in which one of the left and right crawler type traveling devices 1 is braked and the other crawler type traveling device 1 is driven. Further, by swinging the operation lever 113 in the vertical direction, the traveling state, the cut-off state where transmission to both the left and right crawler type traveling devices 1 is interrupted, and the both left and right crawler type traveling devices 1 are The brake state to be braked can be switched and displayed.
[0069]
Incidentally, the operation lever 113 is configured to be extendable and contracted, and the above-described switching operation from the dismounting position can be performed by extending the operation lever 113 against the bias of the spring 117 that contracts and holds through the linkage wire 116. It can be made easy to do. A reference numeral 118 shown in FIGS. 18 to 20 is a lock fitting that prevents the operation lever 113 from swinging relative to the operation pedal 103 by engaging with the operation lever 113.
[0070]
As shown in FIGS. 22 to 26, a support frame 120 is installed from the mission case 60 to the side panel 119 of the control unit 6, and a cylindrical boss portion 122 is fitted into the circular hole 121 of the support frame 120. Thus, a swing bracket 123 supported so as to be able to swing back and forth is provided. The swing bracket 123 can swing integrally in the front-rear direction via the support shaft 124 and around the support shaft 124. A shift lever 125 supported so as to be capable of relative swinging is provided as an example of an operating tool.
[0071]
As shown in FIGS. 7, 8, and 22 to 26, the swing bracket 123 is linked to the operation arm 127 of the hydrostatic continuously variable transmission 46 via the linkage link 126, and the shift lever 125 is swung. Linked to the transmission shaft 65 of the gear-type transmission 61 through a linkage rod 128 passing through the center of the boss portion 122 of the bracket 123 and a linkage arm 130 supported by the transmission case 60 around the support shaft 129 so as to swing left and right. Has been.
[0072]
That is, by the movement operation of the single shift lever 125, the continuously variable transmission operation of the hydrostatic continuously variable transmission 46 and the stepped shift operation of the gear transmission 61 can be performed. Compared with the case where a lever is provided, it is possible to save space at the position where the speed change lever is provided and improve speed change operability.
[0073]
In addition, since the linkage rod 128 that links the transmission lever 125 and the gear type transmission 61 passes through the center of oscillation of the transmission lever 125 when the hydrostatic continuously variable transmission 46 is operated for shifting. The effect of the swinging operation of the shift lever 125 in the left-right direction for shifting the shift transmission 61 on the left and right, and the swinging operation of the shift lever 125 in the front-rear direction for shifting the hydrostatic continuously variable transmission 46 are performed. Can be done without receiving.
[0074]
As shown in FIG. 27, the speed change lever 125 has two forward speed change operation paths 132, 133 with different speed ratios arranged side by side in the state of moving from the neutral position toward the front side of the aircraft. The vehicle has a reverse shift operation path 134 from the position toward the rear of the machine body and a selection operation path 135 in the left-right direction that enables selection of each of the shift operation paths 132 to 134, and a guide groove 136 formed in the side panel 119. It is comprised so that operation guidance may be carried out by.
[0075]
  Then, the shift lever 125 is moved in the left-right direction along the selection operation path 135 to switch the position of the transmission shaft 65 in the gear transmission 61 to the low speed forward position, the high speed forward position, and the low speed reverse position. Switching operation and gear ratio switching operation can be performed.On the high speed sideIn the state where it is positioned in the forward speed change operation path 132, the transmission shaft 65 of the gear type transmission 61 is positioned at the high speed forward position. It becomes possible to perform a stepless speed change operation in a relatively wide speed change range up to a relatively high forward limit speed that can appear on the operation path 132. Also, shift lever 125On the low speed sideIn the state where it is positioned on the forward speed change operation path 133, the transmission shaft 65 of the gear type transmission 61 is positioned at the low speed forward position. A relatively fine stepless speed change operation can be performed in a relatively narrow low speed side shift region up to a relatively low forward limit speed that can appear on the operation path 133. Further, in a state where the speed change lever 125 is positioned on the reverse speed change operation path 134, the transmission shaft 65 of the gear type transmission 61 is positioned at the low speed reverse position, so that the speed change lever 125 is moved in the front-rear direction. Thus, a stepless speed change operation from zero speed to the reverse speed limit can be performed.
[0076]
That is, the forward / reverse switching, the gear ratio switching, and the gear shifting on each of the gear shifting operation paths 132 to 134 can be smoothly performed by a series of moving operations along the moving operation path 131 of the single gear shifting lever 125. It is like that.
[0077]
  As shown in FIGS. 7 to 11 and FIG.On the low speed sideOnly when the transmission shaft 65 of the gear-type transmission 61 is positioned at the low-speed forward position (see FIGS. 7 to 9) in the forward transmission operation path 133, the transmission to the harvesting and conveying device 3 is performed, and the transmission lever 125On the high speed sideA state where the transmission shaft 65 of the gear type transmission 61 is positioned at the high speed forward position (see FIG. 10), and the shift lever 125 is positioned at the reverse shift operation path 134. In a state where the transmission shaft 65 of the gear transmission 61 is positioned at the low speed reverse position (see FIG. 11), the transmission to the harvesting and conveying apparatus 3 is cut off.
[0078]
  That is, in the movement operation path 131 of the transmission lever 125,On the low speed sideThe forward speed change operation path 133 is a working device drive region 137 that transmits power to the harvesting and conveying device 3, andOn the high speed sideSince the forward shift operation path 132, the reverse shift operation path 134, and the selection operation path 135 are the work device stop area 138 that does not transmit power to the harvesting and conveying apparatus 3, the moving operation of the single shift lever 125 Not only the speed change operation of the hydrostatic continuously variable transmission 46 and the gear type transmission 61 but also the state in which power is transmitted to the harvesting and transporting device 3 and the power is not transmitted to the harvesting and transporting device 3 according to the speed change state at that time. The status can be switched and displayed.
[0079]
In addition, with the above-described configuration, the harvesting and conveying apparatus 3 can be stopped when the machine body is moved backward without the transmission system for the harvesting and conveying apparatus 3 having a one-way clutch that prevents transmission of reverse rotation power. In addition, even if the transmission system for the harvesting and conveying apparatus 3 is not equipped with a high-speed check mechanism that prevents transmission of high-speed power, the harvesting and conveying apparatus 3 can be stopped when the machine body is advanced at a high speed. For this reason, it is possible to avoid the occurrence of defective operations due to the harvesting and conveying apparatus 3 being driven in reverse rotation or being driven at high speed.
[0080]
  As shown in FIG. 2 and FIG. 27, in the movement operation path 131 of the speed change lever 125, the use frequency increases due to the work device drive region 137.On the low speed sideThe forward speed change operation path 133 becomes less frequently used because it becomes the work device stop region 138.On the high speed sideIt is set at a position that is farther from the driver's seat 5 and closer to the reverse shift operation path 134 than the forward shift operation path 132.
[0081]
  As a result, the frequency of use increases during work travel.On the low speed sideThe shift lever 125 can be moved along the forward shift operation path 133 comfortably without feeling cramped even in a small model having a narrow control unit 6 and when traveling.On the low speed sideIt is easy to perform an alignment operation for frequently moving the shift lever 125 over the forward shift operation path 133 and the reverse shift operation path 134.
[0082]
  As shown in FIGS. 7 to 11 and FIG.On the high speed sideForward shift operation path 132 andOn the low speed sideA transmission ratio selection unit 139 extending to the forward speed change operation path 133 is positioned in a fine speed forward region on the forward side from the neutral position. As a result, when the transmission gear ratio is switched by the moving operation of the transmission gear lever 125 at the transmission gear ratio selection unit 139, the first drive gear 66 and the second drive gear 67, which are meshing members on the upper side in the transmission direction, always rotate. Therefore, the gear ratio can be switched smoothly. As a result, the gear ratio selector 139 may occur when the neutral position where the first drive gear 66 and the second drive gear 67 are stopped is set. The first drive gear 66 and the first driven gear portion 71 and the output gear 73, or the second drive gear 67 and the second driven gear portion 74 are engaged with each other due to the rotation being stopped. Defects can be avoided in advance.
[0083]
  In the selection operation path 135,On the low speed sideThe forward / reverse selection section 140 extending between the forward speed change operation path 133 and the reverse speed change operation path 134 is positioned on the forward side of the speed ratio selection section 139, therebyOn the high speed sideA selection restricting path portion 141 that restricts the movement to the forward shift operation path 132 is provided.On the low speed sideWhen moving the forward shift operation path 133 and the reverse shift operation path 134, the shift lever 125 is moved by passing through the selection restricting path portion 141, so that the shift lever 125 is moved.On the high speed sideAn erroneous operation of moving to the forward shift operation path 132 can be effectively prevented.
[0084]
Further, when the shift operation of the speed change lever 125 in the selection restricting path portion 141 is switched from the reverse drive state to the low-speed forward work state, the first drive gear 66 which is the meshing member on the upper side in the transmission direction is always set. Since it rotates and meshes smoothly with the output gear 73, the shift lever 125 is moved in the neutral position where the first drive gear 66 stops, so that the low-speed forward state for working from the reverse state. The meshing failure caused by stopping the rotation of the first drive gear 66 and the output gear 73 that cannot be meshed, which may occur when switching to, can be avoided in advance.
[0085]
As shown in FIGS. 2 and 22, behind the both forward speed change operation paths 132 and 133 in the side panel 119, there is a threshing clutch lever 142 that is an example of a clutch lever that operates the belt-type transmission mechanism 47 that also serves as a work clutch. When the harvesting clutch lever 143, which is an example of a clutch lever that operates the harvesting clutch 63, is in a state of being tilted and swinging to the forward entry position, the gripping portions 144 and 145 are connected to the reverse shift operation path 134. It is arrange | positioned so that it may be located in the right side.
[0086]
That is, since the threshing clutch lever 142 and the mowing clutch lever 143 are rationally arranged by effectively using the rear portions of the two forward speed change operation paths 132 and 133 that are relatively large spaces, the speed change lever 125 and each clutch lever 142 and 143 can be arranged in a compact manner, so that the space where they are arranged can be saved, and both clutch levers 142 and 143 have their gripping portions 144 and 145 operated in reverse speed. When the clutch lever 142 or 143 is positioned at the entering position, the shift lever 125 is not operated even when the clutch levers 142 and 143 are positioned at the entering position. The moving operation can be easily performed on the reverse shift operation path 134.
[0087]
As shown in FIGS. 22 to 25, 28 and 29, the support frame 120 has the speed change lever 125 at the zero speed position by the return force of the neutral return mechanism 146 in the slow speed region of each speed change operation path 132 to 134. A holding mechanism 147 is provided for returning to the neutral position and holding it at a desired operation position in the speed change area higher than the slow speed area in each of the speed change operation paths 132 to 134.
[0088]
The holding mechanism 147 is restricted from moving to the anti-support frame 120 side by an engagement pin 149 provided on an end of the anti-support frame 120 on the support shaft 148 extending from the support frame 120 serving as a fixing member. In this state, the cylindrical movable body 150 is externally fitted so as to be relatively slidable and relatively rotatable. The ring-shaped pressing member 151, the hook-shaped moving member 152, and the ring-shaped contact are attached to the movable body 150. By providing the first spring 154 that presses the support frame 120 with the swing bracket 123 that swings integrally with the speed change lever 125 in the front-rear direction via the member 153, the speed change lever 125 can be frictionally held. (See FIGS. 23 and 28).
[0089]
The neutral return mechanism 146 is provided with a first ring member 155 that restricts the movement of the pressing member 151 toward the support frame 120 on the movable body 150, and the second ring member 156 and the movable body 150 locked to the support shaft 148. In the meantime, a second spring 157 for biasing the movable body 150 in a direction away from the support frame 120 is interposed, and the engagement pin 149 is allowed to be engaged with the end surface of the movable body 150 on the side opposite to the support frame 120. The movable body 149 is linked to the swing bracket 123 via the operation arm 159 and the linkage link 160 so that the V groove 158 is formed and the state where the engagement pin 149 is located at the bottom of the V groove 158 is the zero speed position. Thus, in the slow speed state (see FIG. 29) in which the center of the engagement pin 149 is located within the groove width of the V groove 158, the shift lever 1 is energized by the urging of the second spring 157 and the guide action of the V groove 158. Returning operation to the zero speed position 5 is configured to be (see Figure 29).
[0090]
In other words, the hydrostatic continuously variable transmission 46 cannot be maintained in the very low speed state, so that the harvesting and transporting device 3 cannot be maintained in the very low speed driving state. Thus, it is possible to avoid the occurrence of work failures such as mowing failure caused by maintaining the state in the slow drive state.
[0091]
Further, since the holding mechanism 147 is configured to have the neutral return mechanism 146, the structure can be simplified and the manufacturing cost can be reduced as compared with the case where they are individually configured.
[0092]
The reference numeral 161 shown in FIGS. 22 to 25 allows the swinging bracket 123 to swing relative to the support shaft 148 of the holding mechanism 147 and the bolt 162 that prevents the swinging bracket 123 from being detached from the support frame 120. Therefore, a pair of upper and lower arc-shaped elongated holes formed on the swing bracket 123 with the center of the boss 122 as a fulcrum.
[0093]
Further, reference numeral 163 shown in FIG. 12 (a) indicates that the steering lever 88 is operated to a position where it abuts from the upper side with respect to a longitudinal support shaft 87 that supports the control lever 88 so as to be swingable in the left-right direction. It is a lowering prevention metal that prevents the lever 88 from swinging forward from the neutral position and prevents the lowering operation of the harvesting and conveying device 3. By this lowering prevention metal fitting, the harvesting and conveying device 3 can be operated by an erroneous operation of the control lever 88. It is possible to avoid the occurrence of inconvenience of unexpected lowering.
[0094]
As shown in FIG. 30, each abduction wheel 14 in the left and right crawler type traveling devices 1 has a core bar that protrudes from the crawler belt 15 to the left and right intermediate portions by spatula drawing in order to simplify the configuration. It is formed in a shape having a circumferential groove 165 that allows the protrusion 164 to be engaged.
[0095]
[Another embodiment]
Hereinafter, other embodiments of the present invention will be listed.
(1) The working machine may be a carrot harvester or a radish harvester equipped with a digging-type harvesting and conveying device 3 as the working device 3, or a rice transplanter equipped with a seedling planting device as the working device 3. Good.
[0096]
(2) The continuously variable transmission 46 is configured such that the end surface of one disk is in contact with the peripheral surface of the other disk, and the stepless transmission can be performed by sliding the other disk with respect to the one disk. It may be configured by a configured disk type continuously variable transmission.
[0097]
(3) As shown in FIG. 31 and FIG. 32, the holding mechanism 147 has a slow cutting position at which the support shaft 148 has a center of the engaging pin 149 within the groove width of the V groove 158 in the slow speed region. The position of the engaging pin 149 can be changed with respect to the fixing member 120 to the non-slow cutting position where the center of the engaging pin 149 comes out of the groove width of the V groove 158 regardless of the speed change region. It is linked to the clutch lever 143 that operates the work clutch 63 so that it is located at the slow cut position in conjunction with the operation of engaging the clutch 63 and is located at the non-slow cut position in conjunction with the cut operation of the work clutch 63. Alternatively, the position changing operation of the support shaft 148 may be performed independently.
[0098]
  Further, in the non-slow cut state in which the support shaft 148 is positioned at the non-slow cut position, the operation tool 125 is shown in FIGS. As shown in FIG.On the low speed sideWhile allowing movement operation via the selection restricting path portion 141 to the forward shift operation path 133, the holding mechanism 147 in the selection restricting path portion 141 is prevented from being held and the operating tool 125 is returned to the neutral position. You may make it equip the neutral return mechanism 166 for the non-slow-speed cut.
[Brief description of the drawings]
FIG. 1 is an overall side view of a combine.
FIG. 2 is an overall plan view of the combine.
[Figure 3] Longitudinal rear view of the drafting device
FIG. 4 is a schematic diagram showing a transmission structure.
FIG. 5 is a longitudinal side view of the main part showing the configuration of the lifting device.
FIG. 6 is a longitudinal rear view of the main part showing the configuration of the lifting device.
FIG. 7 is a schematic diagram showing a transmission structure in a mission case.
FIG. 8 is a longitudinal rear view of the main part of the configuration of the gear transmission.
FIG. 9 is a longitudinal rear view of the main part showing a low-speed forward state of the gear transmission.
FIG. 10 is a longitudinal rear view of the main part showing a high-speed forward state of the gear transmission.
FIG. 11 is a longitudinal rear view of the main part showing the reverse state of the gear transmission.
12 (a) is a longitudinal side view of the main part showing the linkage structure of the control lever. FIG.
(B) Longitudinal front view of the main part showing the linkage structure of the control lever
FIG. 13 is a cross-sectional plan view of the main part showing the linkage structure of the control lever
FIG. 14 is a longitudinal rear view of the main part showing a neutral state of the control lever.
FIG. 15 is a longitudinal rear view of the main part showing a turning operation state of the control lever.
FIG. 16 is a rear view of a main part showing a linkage structure with respect to a side clutch brake.
FIG. 17 (a) A longitudinal side view of a main part showing a lowering operation state of a control lever.
(B) Longitudinal side view of the main part showing the operation of raising the control lever
FIG. 18 is a side view of a main part showing a linkage structure for an operation pedal and an operation lever.
FIG. 19 is a rear view of the main part showing the linkage structure for the operation pedal and the operation lever.
FIG. 20 is a plan view of a main part showing a linkage structure with respect to an operation pedal and an operation lever.
FIG. 21 is a schematic diagram showing another transmission structure in the mission case.
FIG. 22 is a longitudinal sectional side view of the main part showing the linkage structure of the operation tool.
FIG. 23 is a longitudinal side view of the main part showing the forward speed increasing operation state of the operating tool.
FIG. 24 is an enlarged side view of the main part showing the linkage structure of the operation tool.
FIG. 25 is a longitudinal rear view of the main part showing the linkage structure of the operation tool.
FIG. 26 is a cross-sectional plan view of the main part showing the linkage structure of the operation tool.
FIG. 27 is a plan view showing a movement operation path of the operation tool.
FIG. 28 is a partially longitudinal rear view of the main part showing the holding state of the holding mechanism.
FIG. 29 is a partially longitudinal rear view of the main part showing a neutral return start state by the neutral return mechanism.
FIG. 30 is a front elevational view of the main part showing the configuration of the abduction wheel.
FIG. 31 is a longitudinal rear view of the main part showing another embodiment of the holding mechanism.
FIG. 32 (a) is a side view of the main part showing a state in which the support shaft is positioned at the slow cut position in another embodiment of the holding mechanism.
(B) Side view of the main part showing a state in which the support shaft is positioned at the non-slow cutting position in another embodiment of the holding mechanism
FIG. 33 is a side view of the main part showing a state in which a neutral return mechanism for non-slow cutting is equipped in another embodiment.
FIG. 34 is a plan view of the main part showing a state in which a neutral return mechanism for non-slow-speed cutting is installed in another embodiment.
[Explanation of symbols]
3 working devices
46 Continuously variable transmission
63 Working clutch
120 Fixing member
125 operation tool
146 Neutral return mechanism
147 Holding mechanism
148 spindle
149 engaging pin
150 Movable body
151 Pressing member
154 First spring
157 Second spring
158 V groove

Claims (5)

The operation tool of the continuously variable transmission is returned to the zero speed position by the return force of the neutral return mechanism in the fine speed region, and is held at the desired operation position in the speed change region on the higher speed side than the fine speed region. Shifting structure for work implements equipped with a holding mechanism. A fine speed cut state in which the operation tool of the continuously variable transmission is returned to the zero speed position by the return force of the neutral return mechanism in the fine speed region, and is held at the desired operation position in the speed change region higher than the fine speed region. A shift operation structure for a working machine equipped with a holding mechanism capable of switching the operation tool to a non-slow cut state in which the operation tool is held at a desired operation position regardless of a shift region. The slow cut state appears in conjunction with the operation of engaging the work clutch that interrupts transmission to the work device, and the non-slow cut state appears in conjunction with the disengagement operation of the work clutch. The speed change operation structure for a work machine according to claim 2, which is configured as described above. A movable body is externally fitted on a support shaft extending from the fixed member so as to be relatively slidable and relatively rotatable, and the operation tool is connected to the movable body via a pressing member that is restricted from moving toward the fixed member. A first spring that presses against the fixed member, and a second spring that urges the movable body in a direction away from the fixed member between the support shaft and the movable body. Forming a V-groove on the anti-fixing member side of the body for separating the pressing member from the operating tool by engagement with an engagement pin provided on the anti-fixing member side of the support shaft by urging the second spring; The movable body is linked to the operation tool so that the center of the engagement pin is positioned within the groove width of the V groove in the slow speed region, the holding mechanism is provided, and the neutral return mechanism is provided. In addition, the return force of the neutral return mechanism causes the operating tool to move to the zero speed position in the slow speed region. Speed change operation structure of the working machine according to claim 1, wherein is arranged to return. A movable body is externally fitted on a support shaft extending from the fixed member so as to be relatively slidable and relatively rotatable, and the operation tool is connected to the movable body via a pressing member that is restricted from moving toward the fixed member. A first spring that presses against the fixed member, and a second spring that urges the movable body in a direction away from the fixed member between the support shaft and the movable body. Forming a V-groove on the anti-fixing member side of the body for separating the pressing member from the operating tool by engagement with an engagement pin provided on the anti-fixing member side of the support shaft by urging the second spring; The operation tool and the movable body are linked to a state in which the movable body rotates relative to the support shaft in conjunction with the operation of the operation tool, and the support shaft is connected to the fixed member. In the slow speed region, the slow speed cutting position where the center of the engaging pin is located within the groove width of the V groove. The engaging mechanism can be changed to a non-slow cut position where the center of the engagement pin is disengaged from the groove width of the V groove regardless of the speed change region, and the holding mechanism is replaced with the neutral return mechanism. The shift operation structure for a work machine according to claim 2 or 3, wherein the shift operation structure is configured to be switchable between the slow cut state and the non-slow cut state.

Images