JPS5911787Y2 - Agricultural machinery speed control device - Google Patents

Description

[Detailed description of the invention] This invention enables multiple speed change mechanisms installed in the transmission system of the traveling device to perform multi-speed changes by continuous movement of a single speed change operation lever. This invention relates to a speed change operation device for agricultural machinery.

Conventionally, as this type of gear shift operation device, the
No. 68 discloses that two sets of transmission clutches are provided so that the rotation of the motor shaft is transmitted to the transmission via the two sets of clutches, and a plurality of transmission gears are alternately interlocked with each one of the two sets of clutches, Two cam grooves are cut in one speed change plate, two sets of screws that engage with each cam groove are pivoted to separate shafts, and a single operating lever fixed to the speed change plate is operated. Disclosed is a system in which a continuous order of speed changes can be obtained.

This conventional example uses two cam grooves cut into one speed change plate, and is designed to swing two sets of levers around separate shafts at the same time. In order to form two cam grooves into one speed change plate, the desired cam groove cannot be obtained unless the movement angle of the speed change plate is increased.In other words, the swing range of the control lever becomes large, and the control lever becomes This has the disadvantage that the manual operation is unsuitable from an ergonomic point of view, and that the installation space required to secure the swing range of the operating lever is large.

The technical problem to be solved by the present invention is to make the swing range of the operating lever in the above-mentioned speed change operating device ergonomically appropriate and allow manual operation by simple structural improvement. .

The technical measures taken to solve the above technical problems are:
Between the speed change operation arm and the speed change operation lever of the plurality of speed change mechanisms, there are provided two cam plates fixed in parallel to the lever, cam followers that fit into cam grooves formed in each of these cam plates, and the cam follower. A linking cam mechanism is provided, which includes a rocking force arm that is pivotally supported at one end and pivotally supported at the other end to be interlocked with the speed change operation arm, and is swingably supported around a single shaft.

The above technical means works as follows.

Forming separate cam grooves in the two cam plates, or fitting the cam followers of the two rocking force arms into each cam groove,
In addition, since the two rocking force arms are pivotally supported on the first axis, separate cam grooves can be set so that the movement range of each different rocking cam arm is small. The movement angle is reduced, and the swing range of the operating lever is reduced, allowing the lever to be easily operated from an ergonomic point of view.

As a result of the above, the present invention has the following effects, namely:
Since the swinging range of the operating lever can be made small, the installation space required to secure the swinging range of the operating lever can be reduced and the device can be made compact.

．． In particular, since the two swing force arms have one swing shaft, the structure can be made simpler than that of the conventional example which has two swing shafts.

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a tractor as an example of an agricultural machine, and FIG. 2 shows a transmission system in this tractor.

The tractor has an engine 7 in the front part connected to a frame 6 that supports front wheels 5, and a power take-off shaft 10 in the rear part for driving the rear wheels 8, a passenger seat 9, a tiller rotary, etc. The engine 7 and the mission case 11 are fixedly connected via a cylindrical frame 13 with a footrest step 12.

The transmission system is installed inside the transmission case 11, and includes an output shaft 14 that is linked to the engine 7, a wheel drive shaft that is linked to the rear wheels 8 via a differential 15, and a wheel drive shaft that is linked to the front wheels 5. The traveling transmission system to 16 is provided with a main transmission 17 which is hydraulically operated to change gears, and on the downstream side of this in the transmission direction is a planetary gear mechanism that can be switched to two high and low stages of a deceleration transmission state and a non-deceleration state. A first transmission mechanism 1A for use is provided, and on the downstream side of this in the transmission direction,
A second transmission mechanism 1B capable of shifting into two high and low gears is provided.

Further, the transmission system to the power take-off shaft 10 is connected to the output shaft 1.
4 is provided with an intermediate transmission shaft 19 that is interlocked via a transmission mechanism 18, and a clutch that selectively interlocks a transmission shaft 20 to the power take-off shaft 10 with respect to the intermediate transmission shaft 19 and the wheel drive shaft 16. 21 is provided, and the power take-off shaft 1
0 is configured to be switched between a state in which the motor is driven synchronously with the wheels and a state in which it is driven asynchronously.

FIG. 3 shows a speed change operation device for the first and second speed change mechanisms IA and IB, in which a swinging device is mounted on the outer end of each speed change shift shaft 1a, lb protruding from the transmission case 11. Between the free shift operation arms 2A, 2B and the single shift operation lever 3, which is swingable, as the lever 3 continuously swings, the first shift mechanism 1A high and the second shift Mechanism 1B low third gear, first transmission mechanism 1A high;
It is possible to display the fourth speed of the second transmission mechanism 1B high, the first speed of the first transmission mechanism 1A low, the second transmission mechanism 1B low, the second speed of the first transmission mechanism 1A low, and the second transmission mechanism 1B high. A link cam mechanism 4 is provided.

The interlocking cam mechanism 4 has two cam plates 22A, 22B fixed to the lever 3 in parallel, with cam grooves 23A, 23B, respectively, and rods 24A, 24B in the arms 2A, 2B.
Swing cam arms 25A and 2 are interlocked and connected via 24B.
5B is pivotally supported around a single shaft, and a cam follower 26A that fits into the cam grooves 23A, 23B is attached to both swinging power arms 25A, 25B, respectively.
, 26B are arranged in series, and the cam grooves 23A, 23B are shaped so that as the lever 3 swings in one direction, the first transmission mechanism 1A can be adjusted to high, high, or low. , low, and the second transmission mechanism 1B is configured to switch the gears in the order of low, high, low, and high.

Incidentally, between the pair of cam plates 22A, 22B and the transmission case 11, a swing member 28 is provided between the four recesses 27 in the circumferential direction formed in the cam plates 22A, 23B.
An elastic positioning mechanism is provided which elastically holds the lever 3 at four shift swing positions P1, P2, P3, and P4 by elastically engaging the levers.

In addition, in the embodiment, by changing the shapes of the cam grooves 23A and 23B, the gears can be changed from first gear to second gear to third gear to fourth gear as the lever 3 swings. It can be configured as follows.

[Brief explanation of drawings]

The drawings show an embodiment of the speed change operation device for agricultural machinery according to the present invention, in which FIG. 1 is a side view of a tractor (agricultural machinery), FIG. 2 is a transmission system diagram of the tractor, and FIG. 3 is an enlarged side view of main parts. FIG. 4 is a partially cutaway enlarged rear view of the main part, and FIGS. IA, IB...Transmission mechanism, 2A, 2B...
...Speed control arm, 3...Speed control lever
4... Linkage cam mechanism, 22A, 22B... Cam plate, 23A, 23B... Cam groove, 26A, 26 B... Cam follower.

Claims (1)

[Scope of utility model registration request] Multiple transmission mechanisms IA, I interposed in the transmission system to the traveling device
In the shift operating device for agricultural machinery, B is capable of displaying multiple speeds by continuous movement of a single shift operating lever 3, the shift operating arms 2A, 2B of the plurality of shift mechanisms IA, IB. and the speed change operation lever 3, two cam plates 22 A, 22 are fixed to the lever 3 in parallel.
cam followers 26A, 26B that fit into cam grooves 23A, 23B formed in these cam plates 22A, 22B, respectively; and cam followers 26A, 26B.
6B is pivotally supported at one end, and the other end is connected to the speed change operation arm 2A, 2.
A speed change operation device for an agricultural machine, which is provided with an interlocking cam mechanism 4 consisting of rocking force arms 25A and 25B, which are pivotally supported to be interlocked with B and can be rocked around a single shaft.