JPH079745Y2 - Sliding gear lubrication structure for hydraulic clutch and brake type steering device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a slide gear lubrication structure in a hydraulic clutch and a brake type steering device applied to various work vehicles such as agriculture.

(B) Conventional technology A traveling transmission device for a working vehicle is equipped with steering clutches and brakes for the left and right sides of the steering clutch shaft incorporated in the transmission system. Disengage the clutch to stop power transmission to the traveling section on the direction change side,
In addition, it is generally configured to turn the brake while assisting the turning of the vehicle body, but recently, the capacity of the steering clutch and the brake is improved, the intermittent operation force is reduced, and others. For this reason, the steering clutches and brakes described above have been made into a wet multi-plate type so that they can be intermittently operated by hydraulic pressure (for example, Japanese Utility Model Publication No. 62-149668). reference).

By the way, as can be seen in the above-mentioned literature, a hydraulic steering type clutch and brake is a passive gear in which the left and right slide gears that are transmitted to the left and right axles are fitted in the central portion of the steering clutch shaft. It is pivotally supported on both sides of
A wet multi-plate clutch is provided between each slide gear and the passive gear so that the hydraulic piston in the oil chamber formed in the inner cavity of the passive gear intermittently operates the clutch. A wet multi-plate brake is interposed between the outer part and the fixed wall, and these are braked when the steering clutch is disengaged by a hydraulic piston in an oil chamber formed separately from the oil chamber for operating the steering clutch. To switch to
Pressure oil is supplied to each oil chamber through an oil passage formed in the steering clutch shaft.

Further, in the steering device having the above structure, in order to prevent seizure and wear of the left and right slide gears, a fitting sliding surface of the left and right slide gears with respect to the steering clutch shaft is provided from an oil passage formed in the steering clutch shaft. A lubricating oil passage is opened toward the end of the slide gear, and part of the pressure oil for clutch operation is supplied to the above-mentioned mating sliding surface via this lubricating oil passage to prevent seizure and wear of the mating sliding surface of the slide gear. Are considered to do.

(C) Problems to be solved by the invention In the conventional hydraulic clutch and brake type steering device,
Although it is considered that lubrication of the fitting sliding surface of each slide gear is performed by using the pressure oil for operating the steering clutch, specifically, the lubricating oil passage for the left and right slide gears is used. Are only communicated with the oil passages that supply the pressure oil to the steering clutches on the same side, so that the pressure of the hydraulic oil is 0 when the left steering clutch is disconnected, for example.
If this happens, the supply of lubricating oil to the mating sliding surface of the left slide gear will stop, so the load on the mating sliding surface of the slide gear will become particularly large. There was a problem that the durability was not good due to induction of seizure phenomenon and early wear.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to constantly and accurately lubricate a fitting sliding surface of a slide gear with respect to a steering clutch shaft. To provide a sliding gear lubrication structure for hydraulic clutches and brake type steering devices that prevents seizure or wear during vehicle turning when a particularly high load is applied to the mating sliding surface of the slide gear. To do.

(D) Means for Solving the Problems In the present invention, the steering gear is operated between the passive gear fitted to the central portion of the steering clutch shaft and the left and right slide gears fitted right and left of the passive gear, respectively. With the interposition clutch,
A steering brake is provided between the outer side of each slide gear and the fixed wall, and each steering clutch and steering brake are
In the hydraulic clutch and brake type steering device with a structure in which the hydraulic piston of the oil chamber operates intermittently, from the pressure oil supply oil passage to the oil chamber for the left steering brake toward the sliding surface between the left slide gear and the shaft. Pressure oil is supplied from the branched oil passage and the pressure oil supply oil passage to the oil chamber for the right steering clutch via the respective lubrication oil passages, and at the same time, toward the sliding surface between the right slide gear and the shaft. Pressure oil from the pressure oil supply oil passage to the right steering brake oil chamber and from the pressure oil supply oil passage to the left steering clutch oil chamber via the respective lubrication oil passages. The present invention provides a slide clutch lubrication structure in a hydraulic clutch and a brake type steering device characterized by feeding.

(E) Action The hydraulic clutch and brake type steering device configured as described above is incorporated in the traveling transmission system of various work vehicles to be implemented, and the left and right slide gears (7) and (8) are steered. When the clutch (9) (10) is connected to the passive gear (5) and the left and right steering brakes (17) (18) are disengaged,
The power transmitted from the drive source to the passive gear (5) is transmitted to the left and right axles via the left and right slide gears (7) and (8), and the working vehicle travels straight. In this state, a part of the pressure oil supplied to the right steering clutch oil chamber (12) is supplied to the sliding surface of the left slide gear (7) through the lubricating oil passage (32). The sliding surface of the right slide gear (8) is supplied with a part of the pressure oil supplied to the oil chamber (11) for the left steering clutch and is lubricated so that the Fretting phenomenon does not occur.

When changing the direction while the work vehicle is moving, the pressure oil that is being sent to the steering clutch on the side trying to change the direction, for example, the oil chamber (12) of the right steering clutch (10) is switched to the drain state. If operated, the steering clutch (10) on the direction change side is disengaged by that operation, the power transmission to the right axle is interrupted, the right side traveling part is stopped, and the vehicle body is propelled only by the left side traveling part. When turning the vehicle further suddenly, if the oil passage is switched so that the right steering brake (18) becomes effective after the right steering clutch is disengaged, By the braking action of the right steering wheel (18), the turning of the vehicle body is assisted to make a turn with a small turning radius.

By the way, during the above-mentioned vehicle body direction change, a large load is applied to the sliding surface of the direction change-side slide gear (8), and especially when the steering brake (18) is turned in the braking state, Although the load is further increased, the steering clutch (9) on the opposite side to the sliding surface of such a slide gear (8), that is, the sliding surface fitted to the steering clutch shaft, is connected. Since the lubricating oil passage (30) leading to the oil passage (23) that maintains pressure is connected, drain the oil to the steering clutch oil chamber on the direction change side, that is, the oil chamber (12) to eliminate the pressure. Even if the steering clutch is disengaged, the sliding surface of the slide gear (8) continues to be lubricated, and the load applied to the sliding surface of the slide gear further increases.
8) At the time of braking, a part of the pressure oil that brings the steering brake (18) into a braking state is also supplied from the lubricating oil passage (31) to the sliding surface of the slide gear (8) to increase the degree of lubrication. .

(F) Examples Examples will be described with reference to the drawings.

FIG. 1 is a sectional view of a main part of a hydraulic clutch and a brake type steering device according to the present invention. The right side from the center line O shows a state in which the steering clutch is connected and the steering brake is disconnected. The left side of the drawing shows a state in which the steering clutch is disengaged and the steering brake is braked, and FIGS. 2 and 3 are operation explanatory views in which the steering clutch shaft portion in FIG. 1 is extracted and enlarged. Is.

1 to 3, the steering clutch shaft (1)
Is laterally supported on the upper side of the left and right final shafts (3) and (3) supported on the lower end of the mission case (2), and has a passive gear that receives power from the upper shaft (4) at its center. (5) is fitted.

The steering clutch shaft (1) on both the left and right sides of the passive gear (5) has a gear (6) of the final shaft (3) (3).
Left and right slide gears (7) and (8) that constantly mesh with (6) are respectively loosely fitted and supported so as to be slidable in the axial direction,
A wet multi-plate steering clutch, which is connected and disconnected between the inner side of each slide gear (7) and (8) and the left and right wings of the passive gear (5) by axial movement of the slide gear. (9)
(10) are installed respectively.

Each steering clutch (9) (10) is intermittently operated by hydraulic pistons (13) (14) of oil chambers (11) (12) formed in the inner cavity of the passive gear (5), and A spring interposed between the hydraulic piston and the oil chamber wall is elastically biased in the connecting direction.

A wet multi-plate steering brake (17) (18) is provided between the outer side of each slide gear (7) (8) and the fixed wall (15) (16) on the mission case side. , The steering brakes can be switched between the braking release state and the braking state by the hydraulic pistons (21) (22) of the oil chambers (19) (20) formed in the fixed members located on the outer sides thereof. ing.

The oil chambers (11) (1) for the steering clutches (9) (10)
2) and oil chambers (19) (20) for steering brakes (17) (18)
Pressure oil is supplied to the oil passages (23), (24), (56) and (57), and the pressure oil is supplied to each oil passage by a hydraulic pump (27) or An oil passage plate (28) mounted on the mission case (2) with oil that is controlled by a control circuit including a switching valve (not shown) and that is pumped by a hydraulic pump.
It is designed to be supplied via (29).

That is, when the control circuit is operated in a straight-ahead state, the steering clutch oil chambers (11) and (12) are communicated as shown in the right half of FIG. 2 and the left half of FIG. Oilways (23) (24)
Oil is supplied (ON) to each of the above to pressurize each hydraulic piston, and the steering clutches (9) and (10) are kept in the connected state by the biasing action of the spring described above, and the oil for steering brake is The oil passages (56) (57) leading to the passages (19) (20) are in the drain (OFF) state, the steering brakes (9) (10) are kept in the braking release state, and the control circuit is turned to the vehicle body. If the turning direction is changed to the left side, as shown in the left half of FIG. 2, and if the turning direction is to the right, as shown in the right half of FIG. , The pressure oil supply to the oil passage that connects to the steering clutch oil chamber on the turning side is turned off, the steering clutch is disconnected, and oil is further added to the oil passage that connects to the turning braking oil chamber on the turning side. It is supplied (ON) and the turning side steering brake is set to the braking state.

Then, the oil passage (23) leading to the oil chamber (11) for operating the left steering clutch (9) is extended to the fitting portion between the right slide gear (8) and the steering clutch shaft (1). The lubricating oil passage (30) is opened from the extended portion toward the sliding surface of the right slide gear (8), and the oil chamber (20) for the right steering brake is provided on the same sliding surface. A lubricating oil passage (31) is also opened from an oil passage (26) branched from the oil passage leading to the oil passage (24), and an oil passage (24) leading to the oil chamber (12) for operating the right steering clutch (10). ) Is extended to the fitting portion between the left slide gear (7) and the steering clutch shaft (1), and a lubricating oil passage (32) is opened from the extension portion to the sliding surface of the left slide gear. Along with the same sliding surface, lubricate from the oil passage (25) branched from the oil passage leading to the oil chamber (19) for the left steering brake. Road (33) is opened.

Therefore, even when the oil in the oil passage leading to the steering clutch oil chamber is drained due to the disconnection of the steering clutch on the turning side when turning the vehicle body, the sliding surface of the sliding gear on the turning side does not contact the sliding surface. Is a part of the oil that supplies the oil that keeps the steering clutch on the opposite side in the connected state, and when the steering brake on the turning side is in the braking state, turns the steering brake to the braking state. Momo is supplied to the sliding surface of the slide gear.

FIG. 4 shows an example of a traveling transmission mission in which the hydraulic clutch and brake type steering device of the present invention are incorporated.
In this mission, an input shaft (34) is horizontally provided on the upper part of a vertically long mission case (1), and the power from a drive source (not shown) is passively passed by this input shaft (34). Then, in the mission case (1), the input shaft (3
Hydraulic pump (27) that is connected to 4) and is always driven
Are arranged at appropriate positions.

In addition, the opposite end of the input shaft (34) is interlocked with the input of the HST hydraulic unit (35) that is installed side by side with the mission case (1), and goes from the O speed to the maximum speed by passing through the HST hydraulic unit. In this configuration, the rotational force that is continuously variable in the transmission can be transmitted from the output of the HST hydraulic unit back into the transmission case and transmitted to the upper shaft (4) by an appropriate transmission gear mechanism (not shown). Has been done.

5 to 7, the HST hydraulic unit (35)
Can be shifted by rotating the trunnion shaft (37) protruding outward from the storage box (fixed frame, 36). The trunnion shaft (37) has a gear shift operation tool (for remote operation). 38) is attached, and a detent mechanism for maintaining the position of the trunnion shaft (37) in a neutral position is provided between the trunnion shaft (37) and the storage box (36). Then, the illustrated dedent mechanism has the following structure.

A detent rotor (39) is fitted to the trunnion shaft (37) protruding outside the housing box (36).

The detent rotor (39) is a stepped wheel body (41) that is outwardly convex.
And an adjusting wheel body (42) rotatably fitted in the outer small diameter portion (41a) of the wheel body, the adjusting wheel body (42)
A ball indentation groove (43) having a V-shaped cross section is engraved at a predetermined portion of the outer peripheral portion, and a ball (44) supported by the ball indentation groove (43) is provided in the accommodation box (36). Engage with the support part of the detent holder (45) that was set, and use the spring that was set up on the side of the detent holder (45) to insert the indentation groove (4
3) It is designed to suppress the pressure.

In addition, the entire detent rotor (39) has a trunnion shaft (3
The stepped ring body (41) fitted in
The trunnion shaft (3
It is fixed to 7).

In addition, a bulge portion (46) is formed on a part of the outer peripheral portion of the adjusting wheel body (42).
Is formed, and an arcuate slot (47) centered on the axial center of the trunnion shaft (37) is formed in the same portion.
A regulating rod (48) which is erected from the stepped wheel body (41) is inserted into and engaged with the step 7), and is screwed to the bulging portions (46) at both longitudinal ends of the circular arc long hole (47). Adjustment bolts (49) (5
The tip of (0) is brought into contact with the restriction rod (48), respectively, so that the stepped wheel body (41) and the adjustment wheel body (42) can be integrated by cooperating with both bolts.

Therefore, when the 0 speed position of the trunnion wheel (37) and the ball locking position of the detent rotor (39) and the detent holder (45) do not match due to manufacturing error or the like, both the adjusting bolts (49) ( By adjusting the tightening margin of 50) and changing the relative positions of the stepped wheel body (41) and the adjustment wheel body (42), the above-mentioned positional inconsistency can be easily corrected. The other reference numeral (51) in the figure is a thrust bearing,
(52) is a parking brake, (53) is a PTO pulley, (54) is a final case, and (55) is a left axle.

(G) Effect of the Invention Since the present invention is configured as described above, it has the following effects.

Lubricate the sliding surfaces of the left and right slide gears in the hydraulic clutch and brake type steering device with the oil sent from the lubricating oil passages that are connected to the oil passages of the steering clutch oil chambers on the opposite sides. None.In addition, the sliding surface of the left slide gear is lubricated from the lubricating oil passage communicating with the oil passage for the left steering brake, and the sliding surface of the right slide gear is also lubricated from the lubricating oil passage communicating with the oil passage for the right steering brake. Since the oil is supplied, the sliding surface of the slide gear is properly lubricated not only during straight traveling of the vehicle but also when the vehicle travels when a particularly high load is applied to the sliding surface of the slide gear. Therefore, there is an advantage that seizure and early wear of the slide gear are prevented and the life of the steering device is extended.

[Brief description of drawings]

FIG. 1 is a sectional view of essential parts of a hydraulic clutch and a brake type steering device according to the present invention, and FIGS. 2 and 3 are operation explanatory views showing the steering clutch shaft of FIG. 1 in an enlarged manner. FIG. 4 is an overall view of a partially broken stage of a traveling transmission according to the present invention, FIG. 5 is a side view of the partially broken stage of the HST hydraulic unit section of FIG. 4 seen from the direction a, and FIG. FIG. 7 is a partial sectional view taken along the line C in FIG. (1) …… Steering clutch shaft, (5) …… Passive gear (7) (8) …… Left and right slide gears (9) (10) …… Steering clutch, (11) (12) …… Oil chamber (13) (14) …… hydraulic piston, (15) (16) …… fixed wall (17) (18) …… steering brake, (19) (20) …… oil chamber (21) (22)… … Hydraulic piston, (23) (24) …… oil passage (25) (26) …… oil passage, (30) (31) …… lubricating oil passage (32) (33) …… lubricating oil passage

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kaoru Nakano Kaoru Nakano 428 Enami, Okayama City, Okayama Prefecture Seirei Industry Co., Ltd. Examiner Mototsugu Morikawa (56) Bibliography 63-12478 (JP, U) 62-149668 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A passive gear (5) fitted in the central portion of a steering clutch shaft (1) and left and right slide gears (7) (8) fitted right and left of the passive gear (5). The steering clutches (9) and (10) are respectively interposed between the steering gears and the fixed walls (15) and (18) and the steering brakes (9) and (10), respectively. 17) (18), each steering clutch (9) (10) and steering brake (17) (18)
The hydraulic piston (1) of the oil chamber (11) (12) (19) (20)
3) In the hydraulic clutch and brake type steering device that is intermittently operated by (14), (21) and (22), the oil for the left steering brake is directed toward the sliding surface between the left slide gear (7) and the shaft. The oil passage (25) branched from the pressure oil supply oil passage to the chamber (19) and the pressure oil supply oil passage (24) to the right steering clutch oil chamber (12) are respectively connected to the lubricating oil passages (33). ) (3
The pressure oil is fed via 2) and is branched from the pressure oil supply oil passage to the right steering brake oil chamber (20) toward the sliding surface between the right slide gear (7) and the shaft. Oil passage (26),
Pressure oil supply oil passage (23) to the left steering clutch oil chamber (11)
And a slide gear lubrication structure in a hydraulic clutch and brake type steering device, characterized in that pressure oil is fed through the lubrication oil passages (31) (30), respectively.