JPH063215Y2 - Transmission of traveling vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a transmission of a traveling vehicle in which back gears of two types of transmissions are prevented from simultaneously entering.

For example, in a traveling vehicle such as an agricultural tractor, it is required that the number of reverse gears is equal to or about half the number of forward gears from the conventional four gears. A system for switching between forward and backward movement is provided in the system, or a back gear is provided in the auxiliary transmission mechanism in addition to a back gear in the main transmission mechanism so that two sets of transmission mechanisms can each adopt a reverse mode. .

The present invention relates to the latter transmission.

(Prior Art) In a conventional transmission, a main transmission mechanism having a back gear is operated by one main transmission operating lever, and an auxiliary transmission mechanism also having a back gear is operated by one operating lever. The operating means of the speed change mechanism are unrelated and independent, and are arranged in separate blocks in the mission case.

(Problems to be solved by the invention) Therefore, even when the main transmission mechanism is in the back mode, the operation lever of the auxiliary transmission mechanism can enter the back position, and both operation levers are accidentally moved to the back position. If inserted, the vehicle may move forward, which may cause an accident.

(Means for Solving Problems) The present invention provides a back restraining means between the main gear shift operating means B and the sub gear shift operating means C, which releases the other back manner in conjunction with one back manner entering operation. By providing J, it is possible to solve the problems of the prior art.

That is, the concrete structure of the problem solving means in the present invention is, in a traveling vehicle in which the main transmission mechanism B and the auxiliary transmission mechanism C of the traveling drive system are provided with the back gears 31 and 55, respectively, the shift operation means K of the main transmission mechanism B. And a shift operation means L of the auxiliary transmission mechanism C, there is provided a back restraining means J for interlocking with the shift operation of one shift operation means to release the back aspect of the other shift operation means. It is in.

(Operation) When the operation lever 35 of the main transmission mechanism B is operated to put the back gear 31 into the engaged state and the main transmission mechanism B is in the reverse state, the operation lever 43 of the auxiliary transmission mechanism C is moved in the reverse direction 54. When operated to, the pushing piece 45B on the arm shaft 41 rotates the arm shaft 34 via the pushing rod 46B, the arms 50B and 51B, the rod 52, the arms 50A and 51A, the pushing rod 46A and the pushing piece 45A,
The shifter of the back gear 31 via the arm 35 and the fork 33.
30C is returned to the neutral state, and the back mode of the main transmission mechanism B is released. At this time, the back gear 55 of the auxiliary transmission mechanism C is turned on, and the back mode is set.

Similarly, when the main transmission mechanism B is put into the back mode when the sub transmission mechanism C is in the reverse mode, the back restraining means J operates in reverse to return the back gear 55 of the sub transmission mechanism C to the neutral state.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 illustrates a tractor mission 1 of an agricultural tractor, and the power of the engine 2 is the main clutch 3
It is taken out by the tubular traveling propulsion shaft 4 and the PTO propulsion shaft 5 directly connected via the.

The drive system is a dual speed mechanism A, a main speed change mechanism B,
It has an auxiliary transmission mechanism C and a creep transmission mechanism D, and the PTO drive system has a grand drive switching mechanism E and a transmission mechanism F.

In the traveling drive system, the rotation of the traveling propulsion shaft 4 is switched by the hydraulic clutch 6 of the dual speed mechanism A to a direct coupling high speed or a low speed reduced by two stages and transmitted to the main cylinder shaft 7, and the rotation of the main cylinder shaft 7 is performed. Is transmitted to the counter shaft 10 via the four forward gear groups 8a, 8b, 8c, 8d of the main transmission mechanism B and the one reverse gear group 9.

The rotation of the counter shaft 10 is transmitted to the bevel pinion shaft 13 or the first transmission gear group 14a by the first shifter 12a of the auxiliary transmission mechanism C, and the power transmitted to the first transmission gear group 14a is transferred from the auxiliary cylinder shaft 15 to the first transmission gear group 14a. The second transmission gear group 14b and the reverse gear group 16 are transmitted, and the second shifter 12b on the bevel pinion shaft 13 selectively takes out the sub-shift low speed and the sub-shift back from the both gear groups 14b, 16. The auxiliary shift high speed is the first shifter 12a.
The bevel pinion shaft 13 obtained by the direct connection mode of the counter shaft 10 and the bevel pinion shaft 13 by
Is transmitted to the rear wheels via the rear wheel differential mechanism G.

With the second shifter 12b in the auxiliary shift low speed, the first shifter 1
When 2a is engaged with the gear 17 on the bevel pinion shaft 13, the power of the sub-cylindrical shaft 15 is transmitted to the creep transmission mechanism D via the transmission gear group 14b, and the creep cylindrical shafts 19a, 19b are transmitted via the creep shifter 18. When directly connected, the high creep speed is transmitted to the bevel pinion shaft 13 via the gear group 20 and the gear 17, etc.When the creep shifter 18 is moved in the reverse direction, the low creep speed is transmitted to the bevel pinion shaft 13 via the creep reduction gear group 21. It

The rotation of the bevel pinion shaft 13 is transmitted to the first transmission shaft 23 via the gear group 22, and the hydraulic clutch is transmitted from the first transmission shaft 23.
It is transmitted to the second transmission shaft 24 and the front wheel drive shaft 26 via 25.

The main transmission mechanism B has a first speed for switching between the first speed and the second speed.
The shifter 30a and the second shifter 3 for switching between the third speed and the fourth speed
0b and a third shifter 30c for switching the back gear 31 are provided, and the forks 33 slidably supported by the fork shafts 32 are engaged with the respective shifters 30a, 30b, 30c, and the arm shaft 34 is provided with a shaft. The arm 35, which is slidable in a direction and rotatable, is selectively engageable with the three forks 33.
An operating lever 36 for switching the main shift is connected to the arm 35.

Further, in the auxiliary transmission mechanism C, forks 40 on a fork shaft 39 are respectively engaged with a first shifter 38a and a second shifter 38b, and the two forks 40 have an arm 42 on an arm shaft 41. Are selectively engageable. An operation lever 43 for switching the sub-shift is connected to the arm 42.

In FIGS. 1 and 2, push pieces 45A, 45B are provided at the ends of the both arm shafts 34, 41, and the push pieces 45A, 45B are arranged in the vicinity of the push rods 46A, 46B. Can be pushed.
Axis pivotally supported by a support 48 fixed to the mission case 47
A connecting arm 50 and an interlocking arm 51 are fixed to both ends of 49A and 49B, each connecting arm 50 is pin-connected to the push rod 46, and both interlocking arms 51A and 51B are connected to each other via a rod 52. Has been done. A guide plate 53 for guiding the push rod 46 is provided on each of the support bases 48.

A push piece 45 between the two operation levers 36 and 43, a push rod 46,
The arms 50 and 51, the rod 52, and the like constitute the back restraining means J, and from the state in which the main operation lever 36 is tilted to bring the main transmission mechanism B into the back mode, the sub operation lever 43 is moved to the arrow in FIG. When the second shifter 12b is tilted in the 54 direction and the second shifter 12b is engaged with the back gear 55 of the reverse gear group 16 to switch the auxiliary transmission mechanism C to the reverse mode, the pusher piece 45B on the auxiliary operation lever 43 side pushes the push rod 45B. Push 46B, arms 50B, 51B, rod 52
Also, the push rod 46A is interlocked via the arms 51A and 50A, and the main operating lever 36 is pushed to the neutral state via the pushing piece 45A in the back mode. Even when the sub-operation lever 43 is in the back mode first, the back mode of the sub-transmission mechanism C is released by the operation of entering the back mode of the main operation lever 36, similarly to the above operation.

In the back restraining means J shown in FIGS. 1 and 2, since the two push rods 46A and 46B are interlockingly connected, the main / sub operation lever 3
It is especially useful when 6,43 are separated from each other in the left and right direction and the front and rear direction of the mission case 47.
The spaces may be connected by push-pull wires. When the main and sub operation levers 36 and 43 are separated only in the front-rear direction, one push rod 46 is arranged between the two push pieces 45A and 45B, or when they are separated only in the axial direction. , As shown in FIG.
The back restraining means J can be constituted by disposing the pushing pieces 45A and 45B facing each other. In addition, in FIG.
Reference numeral 57 denotes a shift guide groove of the main shift operation lever 36, and 58 denotes a shift guide groove of the sub shift operation lever 43.

Further, the back restraining means J is not only between the main and sub operation levers 36 and 43, but also a member for transmitting the lever operation force, for example, the main and sub shift operation means K such as the arms 35 and 42 and the forks 33 and 40.
It may be provided between the members forming L.

Further, there is a case where the subtransmission mechanism C is composed only of a forward gear group (or a two-axis direct-coupling shifter) and a back gear group (a forward / reverse switching mechanism). In that case, the operation lever 43 is 2
Since the position is switched, one end of the back restraining means J, that is, the push rod 46B is one of the members forming the auxiliary shift operating means L.
It may be connected so that it can be linked together.

FIGS. 4 and 5 show an example of the hitch device 61, in which a mounting base 62 is fixed to the rear lower portion of the mission case 47 by bolts, and a cross member 63 is rotated around the horizontal shaft via a pivot shaft 64. It is movably connected. Cross member 63 front and rear 2
A pair of mounting plates 65 and 66 is fixed, and a hitch member 67 is mounted.

The hitch member 67 has a front end connected to the mounting plate 66 via a pin 68 so as to be swingable about a vertical axis, and an intermediate portion of the hitch member 67 has two pins on the mounting plate 65.
It is positioned right and left via 69, and has a hitch pin 71 for connecting a connecting ring 70 of a tow vehicle such as a trailer to the rear portion thereof.

A pair of left and right dampers 73 are provided between the cross member 63 and the mission case 47. The damper 73 has a cylinder member 74 pivotally supported by the mission case 47, an upper part inserted therein and a lower part formed by a cross member 63.
A piston member 75 pivotally supported by the cylinder member 74, and a spring 76 that is fitted between the cylinder member 74 and the piston member 75 and presses the piston member 75 upward. The retaining pin 77 is provided so as to penetrate the piston member 75 and is inserted into an axially elongated hole 78 formed in the cylinder member 74.

According to the hitch device 67, when a bending motion occurs between the tractor and the towing vehicle during traveling on a rough road and a downward impact load is applied to the cross member 63, the cross member 63 resists the spring 76 of the damper 73. It rotates about the pivot 64 and absorbs the impact load. Therefore, the cross member 63 can be bent following the relative vertical movement of the towing vehicle with respect to the tractor, and the posture of the towing vehicle is maintained while traveling on a flat road.

In the damper 73, a spring that opposes the spring 76 is added in the cylinder member 74 so that the pin 77 is located at the center of the elongated hole 78 to allow the cross member 63 to swing vertically from the horizontal position and to move vertically. The spring force may be balanced.

A cushion member 79 made of hard rubber or the like is provided between the hitch member 67 and the rear mounting plate 65. The cushion member 79 is attached to the hitch member 67 or the rear mounting plate 65 via an adhesive or a stopper, and buffers the bending load, impact load, etc. applied to the hitch member 67, and improves the durability of the cross member 63. At the same time, it is possible to change to an inexpensive material.

(Effect of the Invention) According to the present invention described in detail above, the back restraining means J is provided between the operating means K of the main speed change mechanism B and the operating means L of the auxiliary speed change mechanism C. , C is the back gear 3
Even if it is equipped with 1,55 and can adopt the back mode, when one is put in the back mode, the other back mode is released, and at the same time, it does not become the back mode, and an accident due to involuntary forward movement is ensured. Can be prevented.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention. FIG. 1 is a diagram showing the entire transmission, FIG. 2 is a perspective view of a back restraining means, and FIG. 3 is a modification of the back restraining means. A plan view showing
4 and 5 show one example of the hitch device, FIG. 4 is a partial sectional side view, and FIG. 5 is a sectional view taken along the line VV of FIG. B ... Main transmission mechanism, C ... Sub transmission mechanism, J ... Back restraining means, K ... Main shift operating means, L ... Sub shift operating means, 7 ... Main cylinder shaft, 9 ... Forward gear group , 15 …… Secondary cylinder shaft,
16 …… Reverse gear group, 31 …… Back gear, 36 …… Operating lever, 43 …… Operating lever, 55 …… Back gear.

Claims (1)

[Scope of utility model registration request] 1. A main transmission mechanism B and an auxiliary transmission mechanism C of a traveling drive system.
In the traveling vehicle in which the back gears 31 and 55 are respectively provided, the gear shift operation means K of the main speed change mechanism B and the gear shift operation means L of the sub speed change mechanism C are interlocked with the operation of entering the reverse state of one speed change operation means. Then, there is provided a back restraint means J for releasing the back mode of the other shift operation means, the transmission device for a traveling vehicle.