JPS6229423A - High speed creep restraint device - Google Patents

Abstract

PURPOSE:To prevent a gear shift lever from a rotation to a higher speed position effectively, by extending a restraint arm from a creep gear shift lever projecting from a creep gear shift kit up to the rotating portion of the gear shift lever. CONSTITUTION:A creep gear shift kit C is formed with a counter shaft and plural gears supported integrally to a bearing holding cover 10 which is inserted and fixed at the side opening of a transmission case M. In this case, at the other end of a lever axis 9 which is fixed to a creep gear shaft lever 1, a rotary arm is installed and at the end of the arm is arranged a shifter (both are omitted in the figure). At the same time, at the said lever 1 is furnished the first restraint arm 3 projecting from the lever 1, and at the top of the first rest-raint arm 3 is pivotted the second restraint arm 5 through a pin 4. In a long slit 5a formed at the other end of the arm 5 is inserted a lever axis 8 of a sub gear shift lever 2. When the lever 1 is placed at the creep shift position, the sub gear shift lever 2 is prevented to rotate to the higher speed position by a restraint pin 6 geared to the arm 5.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a creep transmission device for agricultural tractors, etc., which enables shifting to ultra-low speed for special low-speed work such as trenching. It is.

(B) Prior Art The technology of providing a creep transmission device for ultra-low speed work in trenchers and the like has been known for some time.

In addition, in case a dangerous situation occurs when shifting to a high speed gear in the transmission device of the agricultural tractor, etc.,
Techniques in which a check device for high-speed shifting is provided are also known. For example, Japanese Patent Application Laid-Open No. 56-31574.

(C) Problems to be Solved by the Invention An object of the present invention is to provide an agricultural tractor, etc., with a main transmission and a sub-transmission, and furthermore, to provide a structure that can be operated independently of these transmissions to prevent creep. In a transmission equipped with a transmission, at the highest speed of the auxiliary gear or main gear,
If you accidentally shift into creep gear, while driving at high speed with a normal gear ratio, the vehicle will suddenly enter creep gear, resulting in an abnormally large gear ratio and engine braking. Excessive torque is applied to the gears and shafts for the main transmission and auxiliary transmission inside the transmission case, causing accidents such as breakage and cracking. The present invention is designed to prevent such a erroneous creep shift operation from occurring during high-speed driving.

In the past, the creep gear was defined as one of the auxiliary gears, so when both the high speed of the main gear and the high speed of the auxiliary gear were selected and the highest speed was selected, the creep gear was further selected. However, in the case where the main shift, the sub-shift, and the creep shift are configured to be able to be operated independently as in the present invention, the high speed of the sub-speed shift and the high speed of the main shift are selected. It is possible that creep shifting may be selected at the highest speed.

(d) Means for Solving the Problems The objects of the present invention are as described above. Next, the configuration for achieving the objects will be explained.

A check arm is extended from the creep shift lever protruding from the creep shift kit to the rotating part of the shift lever, and when the creep shift lever is rotated to the creep speed position, the check arm is moved within the rotation path of the shift lever. By protruding toward the end, the gear shift lever is configured to prevent the shift lever from being rotated to a high speed position.

(E) Embodiments and Functions The objects and structure of the present invention are as described above, and the present invention will be described in detail together with the structure of the embodiments shown in the accompanying drawings.

Fig. 1 is a side view of the high-speed creep restraint device of the present invention;
The figure is a side view of a part of the creep shift lever and the auxiliary shift lever when the creep shift is not engaged, FIG. 3 is a side view of the creep shift lever in the same creep shift position, and FIG. 4 is a plan sectional view of the creep shift kit.

The creep transmission kit C of the present invention includes a transmission case M
A counter shaft 18, a large-diameter gear 15, and a small-diameter gear 16 are integrally supported by a bearing support lid 10 that is fitted and fixed in a side opening of the bearing support cover 10.

Therefore, when the creep transmission kit C is removed, the tractor becomes a normal spec tractor without a creep transmission device, and the creep transmission kit C can be inserted only when necessary. The gear 17 that meshes with the small diameter gear 16 on the mission case M side is also used as a fixed gear for the sub-transmission.
If the sliding gear 14 and 11-p transmission kit C is not installed, it will be used as a coupling between the output shaft 12 on the main transmission side and the input shaft 13 on the auxiliary transmission side, so it will not be wasted. It is.

Due to the rotation of the creep shift lever 1, in the case of non-creep shift, the main shift side output shaft 12 and the sub-transmission side input shaft 1
3 are directly connected to each other by the sliding gear 14, and the speed is not very low.

In the case of creep shifting, the rotation of the creep shifting lever 1 causes the sliding gear 14 to shift to the large diameter gear 1 on the counter shaft 18.
5, the gear is decelerated, and the gear is decelerated again between the small diameter gear 16 and the gear 17, and the rotation is transmitted to the input shaft 13 on the sub-transmission device side.

By sliding the sliding gear 14, a non-creep speed change or a creep speed change is selected.

However, because the creep shift and the sub-shift or main shift are configured separately, as mentioned above, when the main shift is high and the sub-shift is at its highest speed, the creep shift may be entered due to an operational error, resulting in engine braking. This may cause an accident in which the gears and shafts for the main transmission and auxiliary transmission inside the transmission case M are broken.

As shown in FIG. 1, the creep shift lever 1 is fixed to a lever shaft 9, and the lever shaft 9 rotates a rotating arm 19 to move a shifter 20 at the tip of the rotating arm 19 back and forth. Then, the sliding gear 14 is slid. 22 is a detent device for the creep shift lever 1.

In the present invention, a first check arm 3 projects from the creep shift lever 1, and a second check arm 5 is pivotally supported by a locking pin 4 at the tip of the first check arm 3.

A long hole 5a is opened at the other end of the second check arm 5, and the lever shaft 8 of the sub-shift lever 2 is fitted into the long hole 5a.

Further, the restrained arm 7 that rotates with the rotation of the sub-shift lever 2 protrudes from a part of the sub-shift lever 2 or the lever shaft 8, and when the creep shift lever 1 is in the creep shift position, the second restraint arm 5 Accordingly, the restrained arm 7 is configured to be unable to rotate to a high speed position. Reference numeral 11 denotes a biasing spring that pushes the second restraining arm 5 in the direction of the restrained arm 7 .

As shown in FIGS. 2 and 3, by rotating the sub-shift lever 2 to the shift position, the check pin 6 at the tip of the check arm 7 moves to four positions such as F3, F2, and N-Fl. Change it. In this embodiment, only the third speed of the sub-shift is disabled during creep shifting.

That is, when the creep shift lever 1 is in the non-creep shift position as shown in FIG. 2, the second restraint arm 5 is lifted upward by the first restraint arm 3 and the locking pin 4, The check pin 6 at the tip of the arm 7 can be rotated to the third forward speed position without engaging the end face of the second check arm 5.

On the other hand, in the state shown in FIG. 3, since the creep shift lever 1 has been rotated to the creep shift position, the second check arm 5 has also moved to the full position of the elongated hole 5a. Due to the presence of the second restraining arm 5, the restraining pin 6 of the restrained arm 7 is locked, and the speed change operation to the third forward speed is not possible.

Conversely, even if an attempt is made to shift into a creep shift when the sub-shift is in the third forward speed, the check pin 6 and the second check arm 5 engage, so the creep shift will not be entered. In other words, the configuration is such that the creep shift state and the high position of the auxiliary shift cannot occur together.

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

First, when the agricultural tractor is running at a fairly high speed with the gear in its highest gear position, a sudden creep shift occurs due to an operator error, which is similar to engine braking. As a result, excessive torque is applied to each gear and shaft in the transmission case M, resulting in a slip-off accident. However, if the structure of the present invention is configured as in the present invention, creep shifting will not occur when driving at high speed on the road. This prevents accidents like this from occurring.

Second, conversely, while working at extremely low speeds using a trencher, etc., if the main gear or sub-shift suddenly enters high speed, the aircraft may shake or the gears in the mission case M may be damaged. There is no possibility of breaking the shaft.

[Brief explanation of the drawing]

Fig. 1 is a side view of the high-speed creep restraint device of the present invention;
The figure is a side view of a part of the creep shift lever and the auxiliary shift lever when the creep shift is not engaged, FIG. 3 is a side view of the same in the creep shift position, and FIG. 4 is a cross-sectional plan view of the creep shift kit. . M...Mission case C...Creep gear shift kit...Creep gear shift lever 2...Sub-shift lever 3...First restraining arm 4...Locking pin 5 ... Second check arm 6 ... Check bottle 7 ... Checked arm

Claims (1)

[Claims] A check arm is extended from the creep shift lever protruding from the creep shift kit to the rotating part of the shift lever, and when the creep shift lever is rotated to the creep speed position, the check arm is moved within the rotation path of the shift lever. 1. A high-speed creep check device, characterized in that the device is configured to prevent a gear shift rotation operation of a gear shift lever to a high-speed position by protruding to a high-speed position.