JPS628448Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a transmission device suitable for a PTO transmission device or the like installed at the rear of a rear axle case of an agricultural tractor.

Conventional PTO transmissions employing a selective sliding type using spur gears, which are known in the art, cannot perform multi-stage shifting of three or more stages using a single shift fork. Further, even if the gearbox is capable of multi-speed shifting, the mechanism is complicated and the creep phenomenon occurs when the gear is in neutral.

In view of the above-mentioned problems, the present invention provides a transmission device that can perform multi-stage shifting of three or more stages with a single shift fork, has a simple structure, and can prevent the occurrence of creep phenomenon when in neutral. This is the purpose of this invention, and will be explained below with reference to the drawings.

In the figure, 5 is the driven side PTO axis (driven axis), 6
is a PTO pinion shaft (drive shaft) on the drive side, and both shafts are supported by the rear axle case 3 and the plate 4 integrated therewith via bearings 7 to 10.
The rear end of the PTO shaft 5 (the right end in the figure) protrudes rearward from the rear axle case 3, and the PTO pinion shaft 6 extends forward (to the left in the figure) via a connecting shaft.
Engine via PTO clutch (both not shown)
Connect to. A first helical gear 12 is fitted onto the PTO shaft 5 via a needle bearing 11 at a boss cylinder 13, and a second helical gear 14 is mounted on the boss cylinder 13 and rotates at a boss cylinder 15. Fit freely, both gears 1
2 and 14 are always engaged with fixed PTO pinions 16 and 17 (drive pinions) on the PTO pinion shaft 6. A spline collar 18 is spline-fitted onto the PTO shaft 5, and a splined claw 19 is spline-fitted onto the first gear boss barrel 13 between the spline collar 18 and the second gear boss barrel 15. 18, splined claw 19, external spline 20 provided on each outer periphery of the boss cylinder 15,
Specifications of 21 and 22 (outer diameter, root diameter, tooth width, number of teeth, etc.)
are arranged.

The slider 23 fits into the external spline 20 of the spline collar 18 at its internal spline 24, and the slider 23 is moved from above the spline collar 18 by the shift fork 26 fitted into the annular groove 25 on the outer periphery. 19 up,
Furthermore, it is slidable onto the second gear boss cylinder 15.
An annular notch 27 is provided at the intermediate portion of the length of the internal spline 24, and the first and second gears 12, 14
With the internal spline 24' on the opposite side meshing with the external spline 20, the other internal spline 24 is connected to the external spline 21 or the external spline 2.
2 can be selectively engaged.

A helical third gear 30 fitted onto the PTO shaft 5 via a needle bearing 29 is constantly engaged with an integral pinion 31 (drive pinion) on the PTO pinion shaft 6, and is attached to the outer periphery of the boss cylinder 32. A toothed spline 33 is provided, and this external toothed spline 33 also has the same specifications as the other external toothed splines 20 to 22. Therefore, while one internal spline 24 is meshed with the external spline 20, the other internal spline 2
4' can be engaged with the external spline 33. Note that 34, 35, and 36 are thrust bearings.

If the PTO pinion shaft 6 is designed to rotate in the right direction (direction of arrow A) when viewed from the engine side, the pinions 16, 17 and the third helical gear 30 are provided with right-handed helical teeth, and the pinion 31 and helical The first and second gears 12 and 14 have left-handed helical teeth. Therefore, in the illustrated neutral state where the slider 23 is only on the spline collar 18, the helical first and second gears 1
2 and 14 receive thrust toward the thrust bearing 34, and the helical third gear 30 receives thrust toward the thrust bearing 35, so that no friction occurs at both ends (B1, B2 portions) of the spline collar 18.

With the rotational force of the engine being transmitted to the PTO pinion shaft 6, the shift fork 26 drives the slider 23 in the direction of arrow I to engage the inner and outer splines 24' and 33, thereby obtaining PTO first gear. It will be done. That is, the rotational force is transmitted from the pinion 31 to the PTO shaft 5 via the third helical gear 30, the slider 23, and the spline collar 18. When the slider 23 is driven in the direction of the arrow from the illustrated neutral state and the splines 24 and 21 are engaged, the PTO second speed is obtained. At that time, the rotational force is
The signal is transmitted from the PTO pinion 16 to the PTO shaft 5 via the first helical gear 12, spline claw 19, slider 23, and spline collar 18. When the slider 23 is further driven in the direction of the arrow and the splines 24 and 22 are engaged, the third PTO speed is obtained. At that time, the rotational force is transmitted from the PTO pinion 17 to the PTO shaft 5 via the second helical gear 14, slider 23, and spline collar 18. The thrust received by the first to third helical gears 12, 14, 30 during power transmission and in neutral is supported by thrust bearings 34, 35, 36.

As explained above, according to the present invention, the driven shaft 5
On both sides of the spline collar 18 spline-fitted on top, 1 or 2 on each side for a total of 3 or 4
Out of each gear 12, 14, 30, the gears 12, 30 other than the second gear 14 near the collar 18 on which two gears are arranged on one side are driven. rotatably supported on the shaft 5;
Of the two gears 12 and 14 arranged on one side, the inner boss cylinder 13 of the first gear 12 on the side away from the collar 18 is extended toward the collar 18 side, and the boss cylinder 1
A second gear 14 is rotatably supported on the second gear 14; a splinted claw 19 provided at the tip of the boss cylinder 13 is disposed between the second gear 14 and the collar 18;
Boss tubes 15 and 3 of gears 14 and 30 other than gear 12
2 and the external tooth splines 22, 33, 21 provided on the splined claw 19 and the external tooth spline 20 provided on the collar 18; the slider 23 can be slid freely on the outer periphery of the collar 18. A shift fork 26 is fitted into the annular groove 25 on the outer periphery of the slider 23; An annular notch 27 is formed in the middle portion of the internal splines 24 and 24' of the slider 23, and the slider 23 is fitted with a collar. 18 external splines 20 and one of the other external splines 21, 22, 33; and each gear 1.
2, 14, 30 to the corresponding 3 or 4 on the drive shaft 6
The teeth of each gear 12, 14, 30 and each pinion 16, 17, 31 are helical, and during operation, each gear 12, 14, 30 Since the twisting direction of the collar is determined so that a thrust is generated in the direction away from the collar 18, the following effects can be expected.

(a) Internal spline 2 on external splines 20, 21, 22, 33 with an annular notch 27 between them
Since a spline clutch of the type that slides the slider 23 having 4 and 24' is formed,
An annular groove 25 provided on the outer periphery of the slider 23
Shift fork 26 and spline 2 fitted to
0, 21, 22, and 33 will not interfere with each other. Therefore, the shift stroke of the slider 23 can be made long, and one shift fork 26 can perform multi-stage shifting of three or four stages.

(b) Gears 12 and 3 arranged on both sides of collar 18
It is possible to prevent wear between the collar 18 and the boss cylinders 13 and 32 and the splined claw 19 of the 0, and also to prevent the creep phenomenon that occurs when in neutral.

When embodying the present invention, two helical gears can be placed on the right side of the spline collar 18 in the same way as the left side, and one on the left side and two helical gears on the right side of the spline collar 18. A helical gear may be arranged. Thereby, it is possible to obtain a three- or four-speed transmission that can be changed using one shift fork 26.

[Brief explanation of the drawing]

The figure is a longitudinal sectional view of a transmission according to the present invention. 5... PTO shaft (driven shaft), 6... PTO pinion shaft (drive shaft), 12... Helical first gear, 13,
15, 32... Boss tube, 16, 17, 31...
PTO pinion (drive pinion), 18... Spline collar, 19... Splined plug, 20~
22, 33... External spline, 23... Slider, 24, 24'... Internal spline, 25...
... annular groove, 26 ... shift fork, 27 ... annular notch, 30 ... gear.

Claims (1)

[Scope of utility model registration request] A total of three or four gears 12, 14, 30 on the driven side, one or two on each side, are arranged on both sides of the spline collar 18 spline-fitted on the driven shaft 5; Of these, the second gear 1 is closer to the collar 18 on the side where two gears are arranged on one side.
Gears 12, 30 other than 4 are rotatably supported on the driven shaft 5; two gears 12, 14 are arranged on one side.
Among them, the first gear 12 on the side away from the collar 18
The inner peripheral side boss tube 13 is extended toward the collar 18 side, and the second gear 14 is rotatably supported on the boss tube 13; between the second gear 14 and the collar 18, the boss tube 1
3; and external splines 22, 33, 21 provided on the boss cylinders 15, 32 of the gears 14, 30 other than the first gear 12, and the spline tooth 19. , the specifications of the external spline 20 provided on the collar 18 are matched respectively; the slider 23 is slidably spline-fitted on the outer periphery of the collar 18; the shift fork 26 is fitted into the annular groove 25 on the outer periphery of the slider 23.
internal spline 2 of slider 23;
An annular notch 27 is formed in the intermediate portion of the collar 18 and the other external splines 21, 22, and
33; each gear 12, 14, 30 can be meshed with one of the corresponding three or four drive side pinions 16, 17, on the drive shaft 6;
Always meshed with 31; each gear 12, 14, 30
The teeth of each pinion 16, 17, 31 are helical; the twisting direction of the helical is determined so that a thrust is generated in each gear 12, 14, 30 in the direction away from the collar 18 during operation. Characteristic transmission device.