JPH026267Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a mechanical transmission device for tractors and construction machinery.

(B) Prior Art Conventionally, a transmission device constructed of a spline collar and a sliding body has been known.

For example, there is a technique described in Japanese Utility Model Publication No. 35-29491.

(c) Problems to be solved by the invention Among gear sliding type transmission devices, a sliding body is provided on the spline collar, and by sliding the sliding body back and forth or left and right, the spline collar and other In the case of a collar shift device that connects engaging external teeth via a sliding body to transmit power, it is particularly difficult to use a half-finished system in which half of the sliding body remains on the spline collar and the other half moves onto the engaging external teeth. If the detent device of the shifter or shifter shaft is not sufficient to transmit power in this condition, the sliding body will be pushed back by the thrust force of the engaging external teeth and the gear will easily come off, causing the gear to come off.

The present invention particularly relates to a method for preventing gear slippage in this color shift device, in which a sliding body, a spline collar, etc. are provided with slits and a tapered groove for preventing slippage.

(d) Means for solving the problem The purpose of the present invention is as described above. Next, the configuration for achieving the purpose will be explained.

Engaging external teeth of spline collar 67 and sliding body 45
The engaging internal teeth of the sliding body 4 slide back and forth in a meshed state.
5 protrudes forward and backward of the spline collar 67, and selectively engages with other engaging external teeth 14a, 17a having the same diameter and the same number of teeth as the spline collar 67.
In the configuration in which the speed is changed in stages, the spline collar 6
A slit 67a is provided in the middle part of the engaging external teeth of No. 7,
A slit 45a is provided in the middle of the engaging internal teeth of the sliding body 45.
, and the slit 67a of the spline collar 67
The front and rear tooth grooves are tapered to prevent coming off, respectively, with diameters decreasing in the front and rear end directions.

(E) Embodiment The purpose and structure of the present invention are as described above. Next, the structure of the embodiment shown in the attached drawings will be explained.

FIG. 1 is a side sectional view of the rear part of the transmission case and the front part of the rear axle case of the tractor.

The shaft 5 has a bearing hole in the portion of the shaft that protrudes into the rear chamber of the transmission case 1, and the tip of the pinion shaft 6 is supported in this bearing hole via a needle bearing.

Furthermore, fixed teeth 14 are carved into the rear chamber protrusion of the shaft 5.

First, the third forward speed is the engagement external tooth 14 at the rear end of the shaft 5.
When the sliding body 45 spline-fitted to the pinion shaft 6 meshes with the pinion shaft 6, the shaft 5 and the pinion shaft 6 are integrated and power is transmitted.

The second forward speed is transmitted from the fixed gear 14 of the shaft 5 to the fixed gear 15 spline-fitted to the counter shaft 7, and the spline-fitted sliding body 20 on the counter shaft 7 engages with the internal teeth 18a of the loosely fitted gear 18. By meshing, the rotation of the counter shaft 7 is transmitted from the internal teeth 18a to the fixed gear 21 on the pinion shaft 6 via the loosely fitted gear 18, resulting in the second forward speed.

In the first forward speed, power is transmitted from the fixed gear 16 on the counter shaft 7 to the loosely fitted gear 17 on the pinion shaft 6, and the engaging external teeth 17a of the gear 17 and the sliding body 45 mesh with each other, thereby causing the forward speed 1 to move toward the pinion shaft. Speed can be conveyed.

In addition, the creep speed can be adjusted by fixing the creep gear set 3 to the side wall of the transmission case.
When the sliding gear 27 of the creep gear set 3 meshes with the fixed gear 16 on the counter shaft 7, the fixed gear 28 is driven via the shaft 30, and the loosely fitted gears 32, 29 on the shaft 31 drive the pinion shaft. Fixed gear 2 on 6
1 is rotated to give the creep velocity.

The reverse speed is determined by the loosely fitted gear 19 on the counter shaft 7.
Since the back gear 46 is interposed between the fixed gear 22 on the pinion shaft 6 and the fixed gear 22 on the pinion shaft 6, this can be achieved by meshing the sliding body 20 with the external teeth 19a.

Rotation of the pinion shaft 6 is transmitted by the pinion 23 to the ring gear 11 of the differential device. The rotation of the counter shaft 7 is transmitted to the shaft 9 by the connecting shaft.

A PTO hydraulic clutch device 36 is interposed between the connecting shaft 8 and the shaft 9. Fixed gear 37 on shaft 9,
38 and the loosely fitted gears 39 and 41 on the PTO shaft 10 are always in mesh with each other, and the height of the PTO shift can be obtained by sliding the sliding body 40 back and forth.

Since the fixed gear 26 on the shaft 12 is always engaged with the fixed gear 22 on the pinion shaft 6, the pinion rotation is taken out to the shaft 12, and the sliding body 42 is connected to the loosely fitted gear via the ground PTO connecting shaft 13. When it meshes with the internal teeth of 44, power is transmitted to the fixed gear 47 on the PTO shaft, resulting in ground PTO rotation.

Also, the fixed gear 26 on the shaft 12 also serves to take out the power to the front wheel drive, and the fixed gear 25 on the shaft 12 meshes with the loosely fitted gear 35 on the shaft 48 of the power take-off gearbox. Front wheel power is extracted by sliding of the sliding body 35a.

FIG. 2 is a side sectional view of the vicinity of the pinion shaft 6 and counter shaft 7, and FIG. 3 is a front sectional view of the parking brake portion.

A brake pulley 23 is fixed on the pinion shaft 6, a brake belt 24 is fitted into the groove of the brake pulley 23, and the brake belt is tightened by operating the parking brake lever, thereby applying the parking brake. are doing.

In FIG. 3, the brake belt 24 of the parking brake device has its front end protruding onto the upper surface of the transmission case 1 via a connecting rod 50, and a nut 51 is attached to the threaded portion of this end to rotate the nut. This adjusts the amount of protrusion of the connecting rod 50 and adjusts the braking force when the brake lever is operated.

The other end of the brake belt 24 is pivotally supported at the center of the arm 52. At the base end of the arm 52, a back gear shaft 72 of the back gear 46 serves two purposes. The other end of the arm 52 is pivotally supported by a link 56 to an arm 55 of a rotation shaft 53.

The rotation shaft 53 comes out of the transmission case 1, and an arm 54 linked to a parking brake lever is fixed to the outside part. Arm 54
The rotation of the parking brake applies the parking brake. The braking force of the parking brake is adjusted by the screw part and nut of the connecting rod 50 at the top of the transmission case.

FIG. 4 is a side view showing the interlocking state of the differential pedal, and FIG. 5 is a rear view.

The differential lock engaging body in the differential device consisting of the differential ring gear 11 etc. in the rear acrylic case,
Slide the differential shifter 65 left and right to lock and unlock the differential device. The differential shifter 65 is normally biased in the unlocking direction by a spring 66, and when the differential pedal 57 is depressed, the shifter shaft 65 is is moved left and right to perform the deflock.

63 is a pivot shaft of the bell crank 61, and 64 is a support for the pivot shaft 63.

Even if the differential pedal 57 is depressed forward,
It doesn't matter whether you step backwards or not.

6 and 7 are side views of the collar shift device in a power transmission state, FIG. 8 is a side sectional view of the sliding body 45, and FIG. 9 is a side sectional view of the spline collar 67.

As shown in FIG. 9, a slit 67a is formed all around the spline on the outer circumference of the spline collar 67 and in the middle of the meshing teeth formed by the involute gear.

Similarly, slits 45a are also provided at corresponding positions in the engaging internal teeth of the sliding body 45.

The effect of this slit is shown in FIGS. 6 and 7.

FIG. 6 shows a state in which the sliding body 45 is meshed with the external engagement teeth 17a of the loosely fitted gear 17, and in this state, the slit 45a of the sliding body 45 is aligned with the rear end of the spline collar 67. It is.

Similarly, the rear end of the meshing teeth of the sliding member 45 matches the intermediate slit 67a of the spline collar 67. When power is transmitted in this state, a load is applied to each of the external engagement teeth 17a, the sliding body 45, and the spline collar 67, so that a subtle deflection occurs at the tips of the teeth, and the slit 45a of the sliding body 45 becomes the boundary. The side that meshes with the external engaging teeth 17a and the portion that meshes with the spline collar 67 are deflected in opposite directions, plus and minus.

Therefore, the rear end wall of the spline collar 67 slightly engages with the rear wall of the slit 45a of the slider 45, thereby restricting the return of the slider.

Similarly, the front end wall of the sliding body 45 is located in the middle slit part of the spline collar 67, and the front end wall of the sliding body 45 is located in the middle slit part of the spline collar 67, and this wall is located in the middle slit part of the spline collar 67. The wall slightly engages with the front wall of the slit of the spline collar 67, and this engagement prevents the sliding member from moving.

Next, as shown in FIG.
The same applies to the case where it is engaged on the a side.

In this case, the rear end wall of the sliding body 45 engages with the rear wall of the slit 67a of the spline collar 67, causing a catch, and the front end wall of the spline collar 67 engages with the rear wall of the slit 45a of the sliding body 45. It locks with the front wall and causes a catch.
By utilizing the fact that the front and rear engaging teeth are slightly bent around this slit, a catch is generated between the spline collar and the sliding body by the amount of this bending, thereby preventing the collar from coming off.

Furthermore, as shown in FIG. 10, the tooth grooves extending back and forth from the slit 67a are provided with retaining tapers 67b and 67c.
It has been established.

In FIG. 10, the spline collar 67 is provided with a slit 67a to prevent it from coming off, and a tooth groove extending back and forth from the slit 67a is provided with a slit 67a.
Retaining tapers 67b and 67c are formed which become smaller in diameter in the direction toward the front and rear ends, respectively.

By providing the retaining tapers 67b and 67c in this way, the deflection of the meshing teeth changes, and the shape of the meshing teeth also changes, making it more difficult for the sliding body to come off.

(f) Effects of the invention Since the invention is constructed as described above, it has the following effects.

First, the meshing teeth on the front and rear sides of the slit for retaining the slit are bent in different directions to the left and right, creating a protrusion on the slit portion, which may stick to the sliding body or the front and rear walls of the spline fitting, or may act as a retainer. Therefore, it is possible to securely prevent it from coming off with a simple structure.

Secondly, the tooth grooves in front and behind the middle slit of the spline collar are tapered so that the diameter decreases toward the front and rear ends.As this taper is a forward taper, it is easy to process and has a simple structure. Despite this, we were able to create a secure structure for preventing it from coming off.

[Brief explanation of drawings]

Figure 1 is a side sectional view of the rear part of the tractor's transmission case and the front part of the rear axle case, and Figure 2 is a side sectional view of the vicinity of the pinion shaft and counter shaft.
Figure 3 is a front sectional view of the parking brake part, Figure 4 is a side view showing the interlocking state of the differential lock pedal, Figure 5 is a rear view, and Figures 6 and 7 are the power transmission states of the color shift device. FIG. 8 is a side sectional view of the sliding body, FIG. 9 is a side sectional view of the spline collar, and FIG. 10 is a drawing in which the spline collar is tapered. 14a, 17a... Engaging external teeth, 45... Sliding body, 67... Spline collar, 45a, 67a
...slit, 67b, 67c...retaining taper.

Claims (1)

[Scope of utility model registration request] Engaging external teeth of spline collar 67 and sliding body 45
The engaging internal teeth of the sliding body 4 slide back and forth in a meshed state.
5 protrudes forward and backward of the spline collar 67, the spline collar 67 selectively engages with other engaging external teeth 14a, 17a having the same diameter and the same number of teeth as the spline collar 67, and changes speed to two stages. A slit 67a is provided in the middle part of the engaging external teeth of the sliding body 45, a slit 45a is provided in the middle part of the engaging internal teeth of the sliding body 45, and the tooth grooves before and after the slit 67a of the spline collar 67 are radially oriented in the front and rear end directions. A transmission device characterized by having small falling-off prevention tapers 67b and 67c.