JPS6220573B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed change operation device for a power agricultural machine such as a power tiller, and the present invention relates to a speed change operation device for a power agricultural machine such as a power tiller, in which a single speed change lever is operated to swing vertically and horizontally, respectively, to perform multi-stage speed changes. The present invention proposes an operating device that allows switching operations to be performed and has a simple configuration.

Conventionally, there is a known device that performs rocking operation in two directions using a single gear shift lever. Since the cam plate moves along with the shift lever in the vicinity of the shifter installation part of the shift case, which is particularly narrow, it is difficult in terms of parts arrangement, and the structure is complicated. Therefore, it is difficult to provide a multi-stage transmission mechanism with more than four stages, for example.

In addition, Utility Model Publication No. 50-16887, which is owned by the applicant.
The idea described in the above publication is also known. Therefore, in this invention, the first and second main shift arms are rotated left and right around a straight line using the supporting part of the gear shift lever and the tip of the sub shift arm, so the main high speed shifter and the main low speed shifter are The vertical width of the engaging part needs to be wide, making it impossible to arrange the main high-speed shifter and the main low-speed shifter compactly, and the tips of the first and second shift arms that engage with the engaging part are transverse. The surface needs to be machined into a circular shape, which requires a large number of man-hours, and the shift lever is bent, making smooth operation impossible. So, this invention
In view of these conventional defects, this proposal was made to solve these problems, and the two engagement grooves provided in each of the plurality of shifters that operate one transmission gear mechanism are used to connect the first and second transmission blocks. A regulating part which is arranged in a divided row on the transmission block and which sandwiches the engagement part of the transmission lever that engages with these engagement grooves from the outside and a shifter which operates the other transmission gear mechanism is set to the first transmission position. The rotation of the operating arm is provided with an engaging portion extending further rotationally forward than the engaging portion of the gear shift lever so as to engage the cam mechanism for shifting between the shift lever and the second gear shift position. The moving base is pivotally supported to the transmission case by aligning it with the center of the spherical part of the transmission lever which is supported by the spherical part on the transmission case,
Moreover, a groove is formed on one side of the ball portion and the rotation base along the longitudinal direction of the transmission lever so that the transmission lever can swing around the axis of the rotation base and in the same plane as the axis. is engaged with a shaft portion provided on the other side, and when the shift lever is swung around the axis, the engaging portion engages and disengages from the engagement groove of each shifter of the one shift gear mechanism, and When the engaging portion operates another speed change gear mechanism via the cam mechanism, and when the speed change lever is operated in the same direction as the axis, the shifter is actuated by the engaging portion. In addition, it is an object of the present invention to provide a speed change operation device for a power agricultural machine, characterized in that the above-mentioned regulating portion is configured to fit into an engagement groove of another shifter while remaining stationary, thereby regulating the unintentional movement of the other shifter. It is something to do.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the attached drawings.
Fig. 2 shows a side cross section of the main part of the main part, and Fig. 2 shows a front cross section of the main part. A shift gear 4 that is always engaged with the gear 2a and is movable only in the axial direction toward the rotating shaft 3, and a shift gear 5 that is also movable in the axial direction.
are fitted into the rotating shaft 3, and the fixed gear 7 fitted into the rotating shaft 6 has a gear portion 4a of the shift gear 4.
However, the gear portion 4 of the shift gear 4 is also attached to the fixed gear 8.
The fixed gears 9 and 10 are fitted to the rotating shaft 6, and the shift gear 5 is engaged and disengaged from the fixed gear 9 or the intermediate gear 11 which is always meshed with the fixed gear 10. The first speed change gear mechanism is provided in such a way that it can be operated. Also, the gear shift lever 1 whose ball portion 12a is supported on the ball seat 1a of the gear shift case 1
2 is swingable in both the vertical and horizontal directions in FIG. 1, and the regulating portions 13a and 13b are configured to vertically sandwich the engaging portion 12b formed on the tip side of the gear shift lever 12 from the outside as shown in FIG. The pin-shaped rotating base 13d of the operating arm 13, which has a fork-shaped engaging portion 13c, is aligned with the center of the ball portion 12a, and is rotated only in the vertical direction in FIG. 1 to the mission case 1. The shaft portion 13e at the tip of the rotating base portion 13d is movably supported, and the shaft portion 13e at the tip of the rotating base portion 13d is fitted into the U-shaped groove 12c recessed in the ball portion 12a.As a result, the gear shift lever 12 swings vertically and horizontally. However, even if it does not rotate around the axis, the U-shaped groove 12c will collide with the shaft portion 13e, so this rotation around the axis is prevented.

The shifter 14 that engages with the shift gear 4 is provided with engagement grooves 14a and 14b that are U-shaped in plan view at intervals, and similarly the shifter 15 that engages with the shift gear 5 is provided with engagement grooves 15a and 15b. established,
The engagement groove 15a is between the engagement grooves 14a and 14b,
Furthermore, by locating the engagement groove 15b at the lowest position, the engagement grooves 14a and 15a are divided into the first shift block and the engagement grooves 14b and 15b are arranged into the second shift block, and these engagement grooves Groove 14a, 1
5a, 14b, and 15b are arranged in a row. Then, when the shift gears 4 and 5 are in their respective neutral positions, by swinging the operating lever 12 up and down along the groove of the lever guide 16, the engagement portion 12b is moved from the engagement grooves 14a to 14 of the shifters 14 and 15. The regulating parts 13a and 13b, which engage with one of the engagement parts 15b and swing up and down as one unit with the engagement part 12b, are engaged with the engagement grooves above and below the engagement groove with which the engagement part 12b is engaged. Since they fit together, the restricting parts 13a and 13b restrain the other shifters that are not engaged with the engaging part 12b from moving inadvertently. Then, when the gear shift lever 12 is swung in the left-right direction, the U-shaped groove 12c is moved to the shaft portion 13e.
Since the operation arm 13 remains stationary, only the gear shift lever 12 swings and the engagement portion 12
The shifter 14 or 15 engaged with the shifter 14 or 15 is moved along the respective shifter stay 17 or 18 to shift the shift gear 4 or 5 of the first transmission gear mechanism.

Next, as shown in FIG.
The rotating shaft 22 is always in mesh with the fixed gear 23.
The gear portion 21a of the shift gear 24, which is provided so as to be able to move only in the axial direction toward the rotation shaft 20 by fitting the gear, can mesh with the internal gear portion 21a of the fixed gear 21. Gear part 24
b meshes with the fixed gear 23, and gear part 24 of 1
If a is engaged with the fixed gear 23, the other gear part 24b
constitutes a second transmission gear mechanism so as to mesh with the fixed gear 9, and a shifter 25 that engages with the shift gear 24;
The cam 27 is fitted into the shifter stay 26 so as to be movable in the axial direction as shown in FIG. A cam groove 28 consisting of a vertical groove part 28b corresponding to the first shift position and a vertical groove part 28c corresponding to the second shift position at both left and right ends is provided, and the cam pin 25a provided on the shifter 25 is inserted into the cam groove 28, and the cam 27 is inserted into the cam groove 28. Since the engaging portion 13c of the operating arm 13 is fitted into the fixed shaft portion 29, when the gear shift lever 12 is swung up and down, the operating arm 13
moves up and down together, and the cam 27 also rotates, so that the engaging portion 12b of the gear shift lever 12 engages
Or, in the position where the cam pin 25a is engaged with the upper engagement groove 14a or 15a of 15, the cam pin 25a is in the lower vertical groove part 28b and the gear part 24a is in the internal gear part 2.
1a, the gear portion 24b meshes with the fixed gear 23, and when the engaging portion 12b of the gear shift lever 12 engages with the lower engaging groove 14b or 19b, the cam pin 25a moves into the upper vertical groove portion 28c. At this time, the gear portion 24a meshes with the fixed gear 23, and the gear portion 24b meshes with the fixed gear 9, so that the second speed change gear mechanism is operated to change speed by vertically swinging the speed change lever 12. That's what I do.

Therefore, the first speed change gear mechanism and the second speed change gear mechanism can be operated to change the speed by the left and right swinging operations and the vertically swinging operations of one speed change lever 12. By increasing the number of shifters, the number of speed change stages of the single speed change gear mechanism can be made into a multi-stage speed change mechanism.

That is, in the illustrated example, the first speed change gear mechanism has four speeds and the second speed change gear mechanism has two speeds, resulting in a total of eight speeds. If three sets are provided, a total of 12 gears can be operated. Also, lever guide 16
is provided with a guide groove that can guide the above-mentioned movement operation of the speed change lever 12.

In the illustration, running wheels are attached to the output shaft from the rotating shaft 22 through a gear train not shown.

Since the shift operating device according to the present invention is configured as described above, the engaging portion 12b of the shift lever 12
Even when the shifter is engaged with one of the engagement grooves 14a to 15b of the shifter 14 or 15 and the shifter is being shifted, the regulating portions 13a, 13b of the operating arm 13
The engagement grooves 13c of the operating arm 13 fit into the engagement grooves of the other shifters, thereby preventing the other shifters from moving inadvertently. The shift gear 24 can be selectively engaged with the fixed gears 23 and 21 or 9 while maintaining the shift gear 24 in the position of Can be operated.

Since the center of the ball portion 12a of the shift lever 12 and the center of the rotation base 13d of the operating arm 13 are made to coincide, the shift lever 12 and the operation arm 13 rotate as one body around the center of the rotation base 13d. The relative position of the engaging portion 12b and the restricting portions 13a, 13b does not change even when the engaging portion 12b moves, and as a result, the shifting operation by the engaging portion 12b and the movement prevention operation by the restricting portions 13a, 13b are always reliable. be. Furthermore, since the rotation of the gear shift lever 12 around its axis is prevented by the engagement between the rotation base 13d and the ball portion 12a, the gear shift lever can be placed in a narrow space inside the gear shift case unlike the conventional device described above. This invention has successfully solved the problem of having to provide a cam plate for regulating the swinging direction.

Further, the movement of the shifter 25 of the second speed change gear mechanism is performed by the engaging portion 13c which extends further rotationally forward than the speed change lever 12 and has a large swing arm diameter, so that the cam 27 swings. As the moving distance becomes longer, the engagement between the cam groove 28 and the cam pin 25a becomes extremely smooth, and there is less stiffness.

As described above, the present invention involves engaging the engaging portions of the gear shift levers in the engagement grooves of the two shifters in the first and second shift blocks so that the gear shift lever is aligned flush with the axis of the rotating base of the operating arm. By simply swinging in the direction, one transmission gear mechanism can be switched and the transmission can be easily changed. At the same time, during this transmission, the engagement groove of the other shifter engages with the restriction part of the transmission arm, and the other shifter By preventing the shifter from moving accidentally, it is possible to perform a safe and reliable gear shift, and by swinging the gear shift lever in a direction perpendicular to the operating direction of the shifter in the neutral position, the shifter can be shifted safely and reliably. The lever is switched between the first shift block and the second shift block of one shift gear mechanism, and the cam mechanism is actuated by the simple rocking of the shift arm accompanying the swing of the shift lever to shift the other gear. The gear mechanism can be easily switched between the first shift position and the second shift position.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Fig. 1 is a side sectional view of the main parts inside the transmission case, Fig. 2 is a front sectional view thereof, and Fig. 3 is a front sectional view of the first transmission gear mechanism. 4 is a front sectional view of the second speed change gear mechanism, FIG. 5 is a perspective view of the speed change lever, FIG. 6 is a front view of the cam, and FIG. 7 is a plan sectional view of the speed change lever. Explanation of symbols, 1...Transmission case, 1a...Ball seat,
2...Input shaft, 2a...Gear, 3, 6, 20, 2
2... Rotating shaft, 4, 5... Shift gear, 4a, 4
b, 24a, 24b...gear part, 7, 8, 9, 1
0, 19, 21, 23... Fixed gear, 11... Intermediate gear, 12... Speed change lever, 12a... Ball portion,
12b, 13c...Engagement part, 12c...U-shaped groove, 13...Operation arm, 13a, 13b...Restriction part, 13d...Rotation base, 13e, 29...Shaft part, 14, 15, 25...Shifter, 14a, 14
b, 15a, 15b...Engagement groove, 16...Lever guide, 17, 18, 26...Shifter stay, 2
1a... Internal gear part, 25a... Cam pin, 27
...Cam, 27a...Circular portion, 28...Cam groove, 28a...Slanted groove portion, 28b, 28c...Vertical groove portion.

Claims (1)

[Claims] 1. Two engagement grooves provided in each of a plurality of shifters that operate one transmission gear mechanism are arranged in divided rows in a first transmission block and a second transmission block, and a transmission gear mechanism that engages with these engagement grooves is provided. In order to engage a shifter that operates a regulating part that sandwiches an engaging part of a lever from the outside and a shifter that operates another speed change gear mechanism with a cam mechanism for shifting between a first speed change position and a second speed change position. , the rotating base of the operation arm, which has an engaging part extending further rotationally forward than the engaging part of the gear changing lever, is supported by the ball part on the gear changing case. It is pivoted to the transmission case so as to be aligned with the center of the ball, and also rotates with the ball so that the speed change lever can swing around the axis of this rotation base and in the same direction as this axis. A groove formed on one side of the shift lever along the longitudinal direction of the base is engaged with a shaft section provided on the other side, and when the shift lever is swung around the axis, the engaging portion is At the same time as engaging and disengaging the engagement groove of each shifter of the gear mechanism, the engaging portion operates another speed change gear mechanism via the cam mechanism, and also moves the speed change lever in the same direction as the axis. When operated, the shifter is actuated by the engaging portion, and the restricting portion remains stationary and fits into the engaging groove of another shifter, thereby restricting the other shifter from moving inadvertently. A speed change operation device for a power agricultural machine, which is characterized by: