JPS6039563Y2 - Hydraulic power transmission shaft end cover structure - Google Patents

Description

[Detailed description of the invention] The present invention forms a transmission oil passage for transmission operation on the transmission shaft for communication with each of the transmission cylinders attached thereto, and covers the end of the transmission shaft that protrudes from the transmission case. The present invention relates to a shaft end cover structure for a hydraulic power transmission, which is attached to the transmission case, and in which an oil passage is formed in the cover to communicate and connect the operating oil passage and the control valve.

In the above structure, when the shaft end cover is attached to the transmission case, the oil passage for speed change operation formed on the transmission shaft and the connection passage formed inside the shaft end cover are configured to be connected to each other. However, pressure oil leaks from between the shaft and the inner circumferential surface of the cover that is in close contact with it, and the leaked oil enters the sealed space formed between the shaft end of the transmission shaft and the inner surface of the cover. When the transmission shaft is filled with oil and a thrust force is applied to the transmission shaft to displace it toward the cover as a result of a gear shift operation, the thrust force is applied directly to the cover via the filled oil. There was a problem with the cover being damaged.

In view of the above points, the present invention has been developed by adding a simple structure.
To ensure that damage to the cover can be avoided when thrust force is applied to the transmission shaft due to the filling of oil leaking from the connection point between the connection path in the cover and the transmission oil path for speed change operation formed on the transmission shaft. The purpose is to

Next, the present invention will be explained based on its implementation.

A traveling vehicle body equipped with a tire-type traveling device 1 is provided with a travel platform 2 that can freely travel around the vertical axis 1, a control section 3 is provided on the travel platform 2, and a control section 3 is provided in the front part of the vehicle. The excavation equipment 4 is provided so that it can be freely rotated, and the vertical axis P of each of the travel platform 2 and the excavation equipment 4 is
A work vehicle is set up so that it can perform ground excavation work, which can also be used to dig side ditches by traveling around Q.

To drive the traveling device 1, pressure oil from the traveling platform 2 is supplied via the rotary joint 6 to a traveling hydraulic motor M provided on the traveling vehicle body, and the rotational driving force of the motor M is converted into hydraulic pressure. The hydraulic power transmission 7 is configured to transmit transmission to the traveling device 1 in a four-speed variable manner.Next, the hydraulic power transmission 7 will be explained.

That is, the transmission case 8 includes an input shaft 9 interlockingly connected to the motor M, and first and second transmission shafts 10 and 11 for speed change.
The output shaft 12 is mounted on a shaft, and the input shaft 9 is connected to the first and second transmission shafts 10 via a gear type transmission mechanism 13.13.
．． 11 is configured to constantly rotate and drive, and the first and second transmission shafts 10.11 are provided with speed change cylinders 14, respectively.
The power can be intermittent through the output shaft 1.
The first to fourth gears 16 for shifting are fitted in a state where they are always engaged with the gear 15 fitted in the transmission case 8, and the gear oil in the transmission case 8 is used as hydraulic oil. As a result, a pump 17 linked to the motor M operates the cylinders 14 . It is designed to operate selectively so that the desired traveling speed can be obtained.

From the control valve V to the cylinder 14...
...Constituting the pressure oil supply path to each, the upper wall 8a of the mission case 8 includes the first gear shift operation oil path R1...
The valve side oil passage r1 formed in the valve body 19 is connected to the first operating oil passage R1.
. . . One end of each is connected in communication via a connection path r2 formed in the packing 18, and the other end side of the first operating oil path R1 . , the lateral side wall 8b of the mission case 8, and the first and second transmission shafts 10.11.
A connecting oil passage R formed between the inner surface of the shaft end cover 21 attached to the transmission case 8 via the packing 20 to cover the end protruding from the transmission case 8 of the transmission case 8.
...The upper ends of each are connected separately, and the connection path R...
. . . each lower end and the transmission cylinder 14 . . .
The first and second power transmission shafts 10.
Oil passage R2 for second gear change operation formed inside each of 11...
. . . is the connection path r formed in the shaft end cover 21.
3... are connected to each other separately.

Forming the connection path R for communicating and connecting the first shift operation oil path R1 and the shaft end cover internal connection path R3, mission case 8
Four grooves 2 are formed in the vertical direction on the outer surface of the horizontal side wall 8b.
2... are bored and formed, and the opening side of each groove 22... is closed by attaching a shaft end cover 21 via a packing 20.

A drain path R is formed to communicate from the valve body 19 into the mission case 8 through the packing 18 and the transmission case upper wall 8a, and the pressure oil supplied from the valve (2) in the non-shifting state is transferred to the mission case 8. It is designed to bring it back inside.

Further, the connection path r2 is connected to the packing 18.
an oil passage r consisting of a notch 23 and a notch groove 24 connected to the notch 23, and communicates the oil passage with the drain passage r4. The oil leaking from the connection path r2 is returned to the transmission case 8 through the oil path rs and the drain path r4.

An annular drain path r6 is formed between the transmission case side wall 8b and the shaft end cover 21 in a state surrounding the entire connection path R formed there, and the first and second transmission shafts are connected to each other. 10.11 A space S1 formed between the intervening sealing material 25 and the inner surface of the shaft end cover 21 outward therefrom.
A drain hole 2 formed in the shaft end cover 21 to communicate with the
6 and 26, respectively, are connected in communication with an intermediate location of the annular drain path r6, and a predetermined location above the drain path r6,
The oil passage r5 formed in the gasket 18 is connected to the oil passage r5 formed in the transmission case upper wall 8a through a drain hole 27 formed in the transmission case upper wall 8a, and the oil leaking into the space S1 and the transmission case side wall 8b are connected to each other. Any oil leaking from the connection path R between the shaft end cover 21 and the shaft end cover 21 is returned into the mission case 8 from the annular drain path r6 through the drain hole 27, the oil path r5, and the drain path r. He is poised to move forward.

Inside the shaft end cover 21 are first and second transmission shafts 10.1.
Drain passages r, r communicating with the sealed spaces S, S formed between the shaft end surfaces of the respective shafts 1 and the inner surface of the cover 21 are formed, and the other ends of the drain passages r, r are connected to the drain holes 26, respectively. , 26, and the connecting path r
3 and the second gear shift operation oil passage R2, the oil leaks and fills the sealed space S and flows freely through the drain passage r, and drains the drain hole 26, the annular drain passage r6, the drain hole 27, and the oil. drain path r for path r5 and valve V
.

The plan is to return it to the mission case 8 through the cable.

In summary, the present invention provides a shaft end cover structure for a hydraulic power transmission that has been officially registered.
The cover 21 has a drain path r communicating with the sealed space S formed between the shaft end face of 0.11 mm and the inner surface of the cover 21.
It is characterized by its strong appearance.

In other words, although it is a simple structural addition of just forming the drain path r communicating with the sealed space S in the shaft end cover 21, the oil path R2 for gear shift operation and the connecting path r3...
・Even if oil leaks from the communication connection point and fills the sealed space S, and in that state a thrust force that compresses the sealed space S is applied to the transmission shaft 10.11, the oil will not be filled as a result of that action. It is possible to prevent the oil from flowing through the drain path r and transmitting the thrust force to the shaft end cover 21 using the oil filled as a medium, and to ensure that the shaft end cover 21 is not damaged due to the oil filling the sealed space S. I was able to avoid it.

[Brief explanation of the drawing]

The drawings show the implementation of the shaft end cover structure of a hydraulic power transmission according to the present invention, in which Fig. 1 is an overall side view of a working vehicle, Fig. 2 is an exploded vertical sectional view of the transmission, and Fig. 3 is a part of the main part. An exploded perspective view, Figure 4 is IV- of Figure 3.
It is a sectional view taken along the line IV. 8...Mission case, 10.11...
...Transmission shaft, 14...Transmission cylinder, 21.
...Shaft end cover, ■...Control valve, R2...Oil passage for speed change operation, r3...
・Connection path, r... Drain path, S... Sealed space.

Claims (1)

[Scope of utility model registration request] A transmission oil path R2 for transmission operation that communicates with the transmission shaft 10, 11 and the transmission cylinder 14 attached thereto.
A cover 21 that covers the end of the transmission shaft 10.11 protruding from the mission case 8 is attached to the mission case 8, and within the cover 21, the operating oil passage R2... This is a shaft end cover structure for a hydraulic power transmission in which an oil passage r3 is formed to communicate and connect a control valve V with the shaft end surface of the transmission shaft 10.11 and the cover. 21. A shaft end cover structure for a hydraulic power transmission, characterized in that a drain path r is formed in the cover 21 and communicates with a sealed space S formed between the inner surface of the cover 21 and the inner surface of the cover 21.