JPS5847659A - Speed change unit of mobile working vehicle - Google Patents

Abstract

PURPOSE:To perform a pivotal turn around a ground point gradually by providing an inching valve capable of being operated with a foot. CONSTITUTION:As the inching spool 61 of an inching valve G is depressed with a pedal, the pressure oil begins to escape through the notch 61b of the spool 61 to a port L through a slant face 61a and the pressure oil flowing into a clutch unit through an auxiliary speed change oil hydraulic control valve E is decreased in accordance with the amount of the pedal depression, then the half-connected condition of the clutch is created at the strength proportional to the decrease. When the pedal is further depressed, the pressure oil escapes to the port L through the notch 61b instead of through the slant face 61a, and the pressure oil of an oil pressure unit flowing from the auxiliary speed change oil hydraulic control valve E escapes to a drain port D through a notch 61c, thereby the auxiliary speed change unit is put in a neutral condition and the vehicle is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission device for a mobile work vehicle that is capable of interlining turning, rapid turning, and intermittent travel.

Construction machinery and transportation machinery work in narrow workplaces, so they are required to rotate the interlining and travel intermittently in the most parallel manner.
In order to load cargo back and forth, repeated forward and backward movements and sharp turns are required.

These special movements need to be performed instantaneously and with simple operation, and cannot be performed using conventional gear-sliding transmissions.
It took time to shift the fi gear, and in the case of the H8T device, it was difficult to determine the speed using the lever, and increasing the speed was dangerous, and there was no mobile work vehicle that could perform all of these special movements. 0 By using a hydraulic clutch device, the left and right speeds can be kept constant, and the H8T
The problem with this device has been solved, and the speed is changed using engine rotation and a sub-transmission device. Switching between forward and backward movement and interlining turns is done by a hydraulic clutch device, and sudden turns are made using a tandem clutch on the turning axis. This was done using a hydraulic brake system installed in

However, in the case of such a mobile work vehicle, in order to rotate the interlining, it is necessary to grasp the interlining rotation lever and tilt it, and it is also necessary to take your hand off the steering lever. Even if I operated one of the -, the interliner turn changed to a sharp turn, and I was unable to stop the aircraft or make a slow turn.

In such a case, the present invention provides an itching pedal that can be operated with the foot, thereby making it possible to gradually rotate the interlining.

The object of the present invention is as described above, and the present invention will be described in detail based on the configuration of the embodiment shown in the accompanying drawings.

Fig. 1 in the margin below is an overall side view of a mobile work vehicle that transports earth, sand, granular materials, and powdery materials, and Fig. 2 is an overall front view of the mobile work vehicle.

Front wheel σ0) -, drive wheel - bucket on top, boom -
), driver's seat σ11, engine compartment on the engine side (8),
The chassis (105) on which the boom is mounted is pivoted by the boom support unit, and the boom is moved up and down by the hydraulic cylinder (67). - The hydraulic cylinder (66) is a hydraulic cylinder that tilts the (kerato) and allows the transported object to fall.For safety, both sides of the operator's cab (2) are covered with wire mesh. Inside, there is a driver's seat (goods), a forward/reverse center pivot lever (to), and a left and right steering wheel (-(106L) (106R),
In addition, the sub-shift lever (107) and the switching pedal (1
08) Figures 1 and 2 show a wheel-type transport vehicle, but this device may also be installed on a crawler-type mobile work vehicle.0 Steering lever (106L) (106R) are installed on the left and right in front of the driver's seat. When pulled, the steering spools line up and when pulled further, the hydraulic brakes are activated. 〇Also, the center of the forward/reverse centering rotation lever (to) is set to neutral H as shown in Figure 9, and in case of forward/backward tilting, With the detent device, the lever (to) is fixed at that position and moves forward or backward, but in the case of interlining rotation that tilts from the neutral axis to the left or right, the lever (to) is biased to return to the neutral position. Interlining rotation is performed only when the steering wheel or hand is tilting to the right or left.Therefore, while turning the interlining, release your hand from one side of the steering lever and operate the forward/backward interlining rotation lever (to). Even if you pull the steering lever with only one hand, the interlining rotation will stop, but the rotation will not stop.

A foot-operated switching pedal is provided to enable slow interlining turns. g Slow or intermittent movement other than interlining turns is possible by pulling the left and right steering levers at the same time. Figure 3 is a power transmission diagram of the mobile work machine, Figure 4 is a drawing showing the arrangement of the shafts in the mission case, Figure 5 is a front view of the mission case (1), and Figure 6 is the same as the mission case (1). The rear view, Fig. 7 is a sectional view taken along the line GG in Fig. 6 of the mission case (1), and Fig. 8 is a cross-sectional view taken along line H-G in Fig. 6 of the mission case (1).
This transmission case (1), which is a cross-sectional view of It is possible to rotate the interlining and change the height of the sub-shift.

There are four shafts arranged inside the mission case (1).The four shafts are the input shaft (7), the sub-shift shaft Q4, the left rotation axis (E), and the right rotation axis α field. (1) has a rectangular shape when viewed from the front, with an input shaft (7) at the top center and an auxiliary transmission shaft (7) directly below it.
2), and the left rotation axis - and the right rotation axis α are placed at positions equidistant to the left and right about the line connecting the input shaft (7) and the auxiliary transmission axes α.
◇On the sub-shift shaft (to) is a tandem-type hydraulic clutch device (24a) that performs high and low sub-shifts.
24b) are arranged back-to-back in one body, and are mounted as a hydraulic clutch device (c).

On the left turning axis (E), there is a hydraulic brake device (
30a), a hydraulic clutch device for reverse (30b) and a hydraulic clutch device for forward (4) are installed, and a hydraulic brake device (30a) and a hydraulic clutch device for reverse (3θb) are installed.
are configured back-to-back with tamp A.

Similarly, on the right turning axis α, a hydraulic brake device for right turning (25a), a hydraulic clutch device for reverse movement (2 items), and a hydraulic clutch device for forward movement (e) are installed. (25a) and the hydraulic clutch device for reverse are configured back to back in tandem. These three hydraulic clutch shafts equipped with hydraulic clutches are connected to the auxiliary transmission shaft (25a).
6) Arrange it in an isosceles triangle with the apex at 0. On the two vertices of the 0 base, arrange the left rotation axis) and the right rotation axis 0.

When traveling forward, power is transmitted from the sub-transmission shaft (6) to the gear QI on the right rotation axis α, and the power is transferred up the right rotation axis O1. Also, when traveling in reverse, power is transmitted from the sub-transmission shaft (6) to the gear QI on the right rotation axis α. The rotation is transmitted to the upper gear (E), and the power is transmitted from the gear (E) to the gear αη on the right rotation axis α.

The basic power transmission path is as described above, and if we follow the power transmission path in detail, we will find that the engine mounted on the chassis of the mobile work vehicle has a shock absorber 151.
), the power is transmitted from the coupling (6) to the input shaft (7) via the universal joint t5at-. Splined coupling (6) on input shaft (7)
A hydraulic pump (4) for a hydraulic clutch type transmission device and a hydraulic pump (5) for a hydraulic brake device are fitted onto the top and are clamped and secured to the rear surface of the transmission case (1) by a pump lid. A mission case lid body aυ is attached to the front of the mission case (1) with the intergate (2) in between. At the front end protrusion of the mission case of the human power shaft (7), there is a coupling (
8) is fitted, and the high-pressure pump is attached to the high-pressure pump mounting body (3) fixed to the mission case lid body αυ.

A large-diameter fixed gear (9) and an absent fixed gear (10) are fixedly mounted on the input shaft (7) inside the mission case (1).

Both fixed gears (9) (10 are always in mesh with the loosely fitted gear (18Qυ) on the auxiliary transmission shaft (2). When the auxiliary transmission low speed hydraulic clutch device (24a) is connected, the fixed gear DI, When the rotation of the loosely fitted gear Qθ is transmitted to the auxiliary transmission shaft (6) and the auxiliary transmission high speed hydraulic clutch device (24b) is connected, the rotation of the fixed gear (9) and the loosely fitted gear (G) is transmitted to the auxiliary transmission shaft (6). (2).This sub-shift's low-speed and high-speed hydraulic clutch devices (z4
aX24b) is selected by an auxiliary transmission hydraulic control valve (g) mounted on the right side of the transmission case when facing the front.

Pressure oil controlled by the hydraulic control valve (G) passes through and carved oil passages, and is transferred from the seal case (A) fitted to the front protrusion of the auxiliary transmission shaft (2) to the auxiliary transmission shaft (2). 2) is guided to the through-hole oil passage inside.

Rotation on the sub-transmission shaft (6) is controlled by wide fixed gear α4.
The right rotation axis (1) is transmitted to the left rotation axis (E). The first half of wide loose fit gear OQ on the right rotation axis [phase] meshes with the rear end of wide gear α , the rear half of the wide loose fit gear (1) on the left rotation shaft (E) meshes with the rear half of the wide loose fit gear α on the right rotation shaft (E). The upper narrow free-fit gear 3υ is always in FIIF meshing, and these two gears αQ31) are always rotating in the forward direction.

The front half of the gear has a narrow free-fit gear αη on the right rotation axis Q3.
are always in mesh with each other, and these two gears (7) and (17) are always rotating in the backward direction of the aircraft. When the hydraulic clutch device (25b) is connected to the shaft (to) on the right turning axis α1, the right drive wheel moves in reverse, and when the hydraulic clutch device (e) is connected, It becomes progress.

If neither of the hydraulic clutch devices (25b) (26) is connected, it becomes neutral. In addition, a hydraulic clutch device (
25b) and the hydraulic brake device C installed back to back.
25&) is connected, if the right drive wheel is coasting, it will be braked and come to a complete stop. Hydraulic brake equipment is used for sharp turns while driving, etc. When parking, the engine stops and no oil pressure is generated, so braking cannot be performed, so the parking brake (B2) is used. is provided on the rear protrusion of the right rotation axis (to) from the mission case (1). Furthermore, the right turning axis α protrudes through the parking brake (B2) and transmits power to the rear axle case through the coupling (82).

Similarly, on the left rotation axis @, the hydraulic clutch device (30
When b) is connected to the shaft), the left drive shaft moves in reverse, and when the hydraulic clutch device (81) is connected, it moves forward. If neither hydraulic clutch device (30b) (191+) is connected, it becomes neutral.Furthermore, when the hydraulic clutch device (aob) and the hydraulic brake device (30a) installed back to back are connected, the left drive wheel becomes If the vehicle is coasting and making noise, the brakes are applied and the vehicle makes a sharp turn.

Hydraulic clutch devices for hydraulic brakes are used for sharp turns while driving.
Since the parking brake (B1) cannot be braked due to the generation of hydraulic pressure when the vehicle (B1) is stopped, the parking brake (B1) is installed on the rear protrusion from the transmission case (1) of the vehicle (B1) with the left turning axis.

Furthermore, the left turning axis (■) also passes through the parking brake (Bl) and protrudes, transmitting the power of the rear axle case through the coupling. be exposed. If both clutches are not ``disconnected,'' it is neutral, but both clutches are not ``engaged,'' and the left rotation axis (
In a), the hydraulic clutch device (30b) (31) is used. Both clutches may be in contact, but both clutches are never in contact.The relationship between the LQQ forward and reverse hydraulic clutch device and the hydraulic brake device is that the forward and reverse hydraulic clutch device is connected to the main shift hydraulic pressure. Even if the left and right spools of the control valve are in "contact" state, the spools 171 of the left and right steering hydraulic control valves, which are also integrally provided in the main transmission hydraulic control valve circuit, are connected. Due to the leakage of hydraulic oil, the hydraulic clutch device is temporarily in a "disconnected" state, and during that time the hydraulic brake device (25a) (30
m) becomes the l-hat state.

Hydraulic control valve for hydraulic brake (Q is transmission case (
Hydraulic two rake device (3) is installed on the left side of the front left side of the hydraulic two rake device (3).
Pressure oil flows to 0a) (25 &) and opens the hydraulic brake lever μs) on the left side and the steering wheel on the left side is linked by a link and the hydraulic clutch device for forward movement +211
7. The hydraulic brake lever on the right side is configured so that the hydraulic clutch for braking lies on its side only when the hydraulic clutch device for reverse (30b) is close to breaking due to a pressure oil leak. v) 9) and the steering spool I71 of the steering hydraulic control valve on the right side, and the hydraulic clutch devices (26) (25b) for forward and reverse movement are close to being in a "disconnected" state due to leakage of pressure oil. The hydraulic brake system is constructed in such a way that it is only necessary after that. The hydraulic pressure that operates the hydraulic brake devices (30a) (25a) is provided by a separate pressure oil system using a hydraulic pump (5).The hydraulic oil tank is also used as the transmission case, and the same lubricating oil is used as the hydraulic oil. However, since there is a communicating oil path between the pressure oils, it will not be affected by the pressure of the other. The pressure oil for forward and reverse movement and the pressure oil for hydraulic brakes are forced to be fed in parallel through the same seal case (c) or through the oil passage penetrating into one shaft Q3C23. Make noise.

The forward/reverse spool of the main transmission hydraulic control valve (4) can be pushed or pulled independently, allowing forward and reverse movement with only the left rotation axis, and forward and reverse movement with only the right rotation axis. If you push and pull the schools together, both left and right will go forward, backward, and neutral. Further, by reversing the left and right spools M (56) by pulling one and pushing the other, the left and right can move forward, backward, and vice versa, allowing the working vehicle to rotate the interlining. This operation is performed by configuring the forward/reverse interlining rotation lever in a cross shape, and a link is configured to rotate the interlining in the left and right direction when tilted from side to side.0 Hydraulic brake device (25a) (aoa) In this case, the case itself of the hydraulic clutch device (E) is used as the rotating side friction plate holder, and the stationary side friction plate holder Ql (A) is fixed to the inner wall of the center plate (2) attached to the transmission case (1). are doing. The material before machining of the friction plate fixed body 0 value is made of the same material as the loosely fitted gear Q'9C1l19 on the auxiliary transmission shaft or the loosely fitted gear on the rotation shaft.0This is a hydraulic clutch device■ This was made possible by using a hydraulic clutch device (c) of the same shape. (85) is an oil filter for sucking lubricating oil into both hydraulic clutches for hydraulic brakes.It is a guide vibrator without a suction hole so that air will not be sucked in even when the front of the aircraft is tilted high. A beak is provided to suck lubricating oil into the suction oil passage between the center plate (2) and the transmission case lid.

Another pulp (G) attached to the front of the transmission case (1) is an inching valve, and when the spool (6) of this pulp (G) is pushed in, the hydraulic pulp side for the main transmission for forward and reverse travels. Pressure oil gradually leaks into the drain circuit on both the left and right sides in proportion to the amount of depression, and is used when the aircraft moves at extremely low speed and approaches other obstacles.

- is Pleaser-1 ■) is the case of oil dipstick (62), Moe 1
41) is a parking brake arm.

In addition, as shown in Fig. 3, at one end of the left and right turning shafts, there is a bevel gear 161 (b) and a final reduction gear +481- which are transmitted through a universal joint into the rear axle cases (2), which are provided separately on the left and right sides. via the rear axle housing) from the upper axle to the drive wheels.

, FIG. 9 is a drawing showing a hydraulic circuit diagram of this device, FIG. The figure is a side sectional view of a hydraulic control valve for hydraulic brakes (side sectional view of Q, FIG. 13 shows inching valve 0).

As mentioned above, the main gear shift hydraulic control valve (outer valve) is located in the center of the upper surface of the mission case (1), and the auxiliary gear shift hydraulic control valve (G) is located on the right side when facing the front of the mission case, and on the left side of the mission case in the direction of travel. The hydraulic control valve for the hydraulic brake (0 is attached to the transmission case lid on the left side when facing the front and the right side in the direction of travel, and the inching valve (G) is attached to the transmission case lid on the right side when facing the front and the left side in the direction of travel. The space for the o-transmission case attached to the case lid 0υ should be narrow since only the input shaft (7) and the sub-transmission shaft 04 are lined up vertically in the upper part. However, if the front side is also narrowed, the mounting surface for the hydraulic control valve and oil passage will become narrower, so the front side of the mission case (1) is made wider and rectangular in shape. Overlap the center plate (2) and the mission case lid θυ to form an oil passage on the mating surfaces, and attach the hydraulic control valve (Q (g) C) to the mission case lid θυ on the front. In addition, the left and right steering spools (for the left and right steering spools) are placed in the main transmission hydraulic control valve (4) and the left and right steering spools (for the left and right forward and backward movement) are placed in one body. 671 is provided protruding from the outer ring of the main transmission hydraulic control toward the front of the mission case (1), and the left and right forward and backward movement spools protrude toward the rear of the mission case (1). This is the steering spool Mfi7) and the left and right brake levers t59 of the hydraulic control valve C) for the hydraulic brake.
)μs), the steering lever (106L
) (106R). Also, since the steering levers (106L) and (106R) are pulled by the operator on the driver's seat, it is convenient to place them in front of the transmission case (1). The distance is right in front of the driver's seat.

To explain according to the drawing, there is a hydraulic pump (4) for the hydraulic crack type transmission and a hydraulic pump (5) for the hydraulic brake system on the coupling (6) of the input shaft (7) to which power is transmitted from the engine. is fitted and sends out pressure oil.
Ru. In order to increase the discharge amount of the hydraulic pump (4) for the hydraulic clutch type transmission device that is closer to the transmission case (1),
The hydraulic pump (5) for the hydraulic brake device, which is located far from the transmission case (1), is narrow and has a small discharge volume.

In addition, a high-pressure pump mounting body (3) is attached to the protrusion from the front end of the transmission case into which the input shaft (7) is inserted, so that the high-pressure pump (1, 09) for the working machine is driven via the coupling (8).
). Hydraulic pumps (4) and (5) both use the lubricating oil from the transmission case (1) as hydraulic oil, and suck it through the oil filter (&5). First, install the hydraulic pump (5) for the hydraulic brake system. ) If you follow the route of the discharged oil, the discharged oil passes through the through oil passage in the mission case (1), the matching oil passage in the center play (2), and the mission case lid body 0), and then reaches the 12F (D7”
Oil is sent to the P port of the v-kibarp case (104).

At the position of the brake spool (95) in Fig. 12, pressure oil enters the drain oil passage (95d) through the notch (95b), and the drain oil passage (95d) passes through the cross oil passage (95e) on the left side. Brake spool (96))” L/-
The drain oil passage (96f) enters the drain oil passage (96f), passes through the notch (96g) of the brake spool (96), and leads to the drain oil passage (96g). The drain oil passage (95f) and notch (95g) in the brake school drawing are provided in a symmetrical position.Similarly, the drain oil in the left spool crosses the drain circuit in the right spool. With this configuration, when you try to apply braking by operating one brake spool, the drain circuit of the other brake spool is closed at the same time, so the pressure oil flows into the other brake. Is it possible to escape from the spool's drain circuit?
0 When the right steering lever (106R) is operated, the steering spool I7+ slides to make forward and backward movement neutral, cuts off the power to the right rotation axis α, and then moves the brake lever - ) rotates and pushes the brake spool (95) downward against the spring (100) via the lever (58a).This causes the brake spool (95) to be pushed down against the spring (100). The drain oil passage (95d) is blocked and the pressure oil flows toward the relief pulp (99) and through the oil passage (95a).
) to the oil path to the hydraulic brake system.

The relief pulp [99] moves upward against the spring (97), and the P port passes from the oil passage (99b) through the notch (99a) of the relief valve (99) to the drain port) (
When the brake lever is further rotated, the body (110) of the spring receiver is pushed by the head of the brake spool (95) through the engagement plate (103), and the spring receiver ( 97), and the inner spring (98
) and spring (97) are contracted, and the relief pulp (99
] to force. As a result, the hydraulic pressure of the P boat gradually increases and the hydraulic brake device (25a) is completely braked. The braking force of the brake device (25a) can be changed linearly. The engagement plate (103) is secured to both the left and right brake arms (58), and by movement of either spool, the relief valve [99], which is provided in the center of the upper surface of the pulp case (104), can be operated. It is also configured to operate and change the relief pressure. (102) is a relief pulp case.

Next, to explain the auxiliary transmission hydraulic control valve (G) in Fig. 11, the pressure oil of the hydraulic pump (4) for the hydraulic clutch device is branched into two directions, one to the main transmission hydraulic control valve and the other to the inching valve. It goes through valve action to the auxiliary transmission hydraulic control valve (g).

The structure of the inching valve (G) is shown in Figure 13, and the hydraulic pump (
4) Pressure oil reaches. The states of the drawings in Figs. 13 and 9 show the inching valve open state, and the hydraulic pump (
4) Pressure oil is sent to the auxiliary transmission hydraulic control valve (G) through the notch (61b) of the inching spool (6) J without being restricted by the inching valve (Q). When the inching pedal (108) is pressed down on the inching valve, it passes through the notch (61b) of the inching valve and slopes (61a) to the L boat for lubricating oil. The pressure oil begins to escape, and the pressure of the pressure oil flowing from the auxiliary transmission hydraulic control valve (g) to the auxiliary transmission hydraulic clutch device (24a) (24b) decreases in accordance with the amount of depression of the inching pedal (108).
A partially engaged state of the clutch occurs with a proportional strength. When the inching pedal (108) is further depressed, pressure oil escapes to the L boat not through the inclined surface (61a) but through the notch (61b) and from the sub-transmission hydraulic control valve (2) to the hydraulic clutch device (24a) (24b). ) The pressure oil in the notch (6
1c) and escapes to tray 7 boat 0, so the sub-shift is in a neutral state and the aircraft stops. In this way, by operating the inching pedal (IOS), you can slow down and stop instantly, so you can operate it like a raw clutch pedal to bring the aircraft closer to the side or slow down. To explain the configuration of the main gear shift hydraulic control outer circuit, the main gear shift hydraulic control valve (4) includes left and right steering spools Q56) h'l) and left and right forward and backward movement spools (154).
1), second relief pulp (2) first relief pulp for smooth starting, accumulator), quick return pulp, etc. are provided.

The pressure oil from the hydraulic pump (4) is divided into three directions, one of which goes through the inching valve (G) to the auxiliary transmission hydraulic control valve (G) as described above, and the other goes to the smooth hydraulic control valve (G). Fast relief valve (86), accumulator (Foundation) and quick return pulp (75) for starting
), and the last one branches in two directions, and branches into the left and right steering spools.

By sliding the steering spool, you can connect and disconnect the pressure oil to the forward and backward movement spool. Do it.

The steering spool value on the right side of Fig. 1θ indicates the engaged state of the steering hydraulic clutch device, and the pressure oil flows to the forward/reverse hydraulic clutch device (E) (25b) at the notch ( 5
7b), it reaches 57a) and flows from the oil path to the forward/reverse spool). Conversely, if it is in the "off" state, the right steering spool is pushed in and the P boat is closed, and the pressure oil in the forward and backward movement spool is released from the oil line.
, bo) (57a) flows backwards and escapes from the notch (57c) to tray 7 port 0. Similarly, the left steering spool) is the same, and the P port notch (56b) (56
c), bow) (56a), and oil passage (85) are provided.

Pressure oil from the right steering spool value) to the bow of the right forward/reverse spool (55a) is transferred from the notch (55c) to the forward/reverse spool shown in Figure 1O in the forward state. It reaches the F boat and enters the forward hydraulic clutch device (toward). At this time, the pressure oil of the reverse hydraulic clutch device flows from the R port to the drain port (2) via the notch (55d).

The left steering spool is in the reverse state in Figure 10, and the pressure oil at the P port (54a) flows from the through oil passage (54b) to the R port, and the pressure oil returns from the F boat. is the notch (112a) of the bar (112)
flowing to the boat.

When the forward/reverse spool (2) is in the neutral position for forward/reverse movement, the bow (54a) (55a) flows to the L port for lubrication. At this time, the pressure oil in the F port flows through the oil passage (54b) (
55b) to the drain port Pressure oil in the R port flows from the notch (54d) to the drain port.

In conventional hydraulic clutch devices, the lubricating oil directed from the lubricating oil passage in the shaft that supports the hydraulic clutch device to the lubricating oil outlet inside the hydraulic clutch device relieves the pressure oil at the outlet of the hydraulic pump. Relief oil from the first relief valve and return oil from the disconnected hydraulic clutch during each gear shift are sent to the lubricating oil port ■ through the oil passage (113a), and each control valve is deactivated when in neutral. The entire amount of pressurized oil was directly returned into the transmission case without going through a second relief valve.

Therefore, the pressure oil from the hydraulic pump is dripped into the transmission case without resistance when it is in neutral, so the first relief pulp does not blow out, and the pressure oil that flows into the lubricating oil drain circuit flows back from each hydraulic circuit. Nominal shi, slight tona shi, each? When the ItlI control valve was in the neutral position, most of the hydraulic clutch devices were not receiving lubrication. However, when each control valve is set to neutral, the friction plates on the stationary side and drive side are rotating directly, so it is important to actively lubricate them.If the neutral state continues for a long time, the lubrication will run out. This causes entanglement and causes the aircraft to move. In this embodiment, the inching valve (when stopping the aircraft by pressing down on Q, and the spool for forward and backward movement) are used.
2) is configured to actively discharge pressurized oil to the second relief valve and to the lubricating oil discharge ports (113) on the left and right rotational axes of the auxiliary transmission shaft (towards) via the oil passage (lx3a). are doing.

As shown in Fig. 10, a line filter installation port (piece) for cleaning the lubricating oil is provided between the lubricating oil discharge port (113) and the second relief valve (2), and as shown in Fig. 5, the left and right pivot shafts g3Q3 are The second relief pulp (2), which sets the pressure of the lubricating oil L port provided between the seal case cover (), is the spool hole dividing body (8N) inserted into the spool hole of the left steering spool (). 81a) and provided at the rear thereof. When the L port oil pressure increases, the second relief pulp (2) moves forward against the spring α9), the L port and the drain port communicate with each other, and low pressure oil for lubricating flows into the transmission case (1). Also, the spool hole dividing body has a pin (8) in the spool hole of the right steering spool value.
0g), and a quick return pulp (75) is provided at the rear for smooth starting. When the forward and backward movement spool moves to the forward and reverse positions in the P port of the quick return pulp (75), pressure oil stops flowing into the drain circuit, pressure is generated, and the quick return pulp (75) is moved against the spring). and push it forward from the inner oil passage (75c) of the quick return pulp to the crest 9 hole (75a).
, from the port (75b) to the port (91a) via the oil passage (91). (91a) is provided in the spool hole of the Fast Relief Pulp (86). Place the first position in the front of the camera. Quick return pulp ('First relief pulp like the phantom P boat (pressure is generated in the P port of the size as well as forward and backward movement and sub-shifting, and first relief pulp (group)
The quick return pulp Cl is pushed backward and flows from the notch (86a) to the pressure oil train port of the P port, and at the same time the quick return pulp Cl is pressed to suppress the sudden pressure rise of the hydraulic clutch device.
5)17) Crest! Hydraulic pressure enters the front part of the accumulator from the D hole (75a) through the oil passage (90a) and pushes the accumulator (c) down, and the flanged spring holder delays the forward movement of the pulp. However, the movement of the accumulator is also a spring ■
), the spring holder is made of pulp (g
'0 moves forward, improves the elastic force of the spring (92), pushes back the first relief pulp (86), limits the amount of relief, and gradually increases the pressure of the hydraulic clutch device.

On the other hand, when the gear shift becomes neutral, the pressure in the P port decreases as pressure oil flows to the lubricating oil port, resulting in a first shift! J-7/<
quick return pulp (7)
5) is returned to its original position by the spring (?8), and the port (75b) of the quick return valve communicates with the drain port in the spring chamber, and the pressure oil of the accumulator flows to the drain, and the accumulator 188) Return it to its original position, and the spring holder that was pushing the spring (92) of the first relief pulp can quickly release the pulp, that is, the spool hole dividing body (90).
By returning the gear to the position shown in the figure, the pressure oil rise during the next gear shift can be brought close to zero. This is why quick return pulp is provided. Switching from forward to reverse,
Since the changeover from the auxiliary gear 1 to the 2nd gear is instantaneous, the spring holder is removed from the pulp (by removing the pressure oil from the back chamber of the spring (92) through the hole (75a)). The pressure is not returned quickly and the hydraulic clutch is connected while the pressure remains high, resulting in a sudden start. and operate these transmissions,
A forward/reverse interlining rotation lever is provided for forward/reverse movement and interlining rotation, and left and right steering levers are provided in front of the driver's seat to turn the rotation of the left and right turning axes on and off regardless of whether the vehicle is moving forward or backward. The inching pedal, which intermittently turns on and off the rotation of the left and right turning axes, can be operated by foot, so when moving forward or backward, the steering lever can be used to connect and disconnect forward and backward movement. When the steering lever (106) cannot be used, the inching pedal is pressed and released with the foot to set the auxiliary gear shift hydraulic clutch device to a half-clutch, thereby enabling intermittent driving and slow driving.

[Brief explanation of drawings]

Figure 1 is an overall side view of a mobile work vehicle that transports earth, sand, granular materials, and powdery materials, Figure 2 is an overall front view, Figure 3 is a power transmission diagram, and Figure 4 is a transmission. Drawings showing the arrangement of the shafts in the case, Fig. 5 is a front view of the mission case (1), Fig. 6 is a rear view of the mission case (1), and Fig. 7 is the 611 G - of the mission case (1). Figure 8 is a cross-sectional view taken along line H-H in Figure 6 of the transmission case (1), Figure 9 is a diagram showing the hydraulic circuit of this device, Figure 1θ is the main transmission hydraulic control valve (8). Fig. 11 is a side sectional view of the auxiliary transmission hydraulic control valve ■, Fig. 12 is a side sectional view of the hydraulic brake hydraulic control valve (Q, and Fig. 13 is a side sectional view of the inching valve C). be. (c) σ Cap... Left and right turning shafts (30bX25b)... Left and right reverse hydraulic clutch devices 3N) (7)... Left and right forward hydraulic clutch devices (
Toughness... Forward/backward centering rotation lever (106L) (106R)... Steering lever (108)... Inching pedal No. 120 58

Claims (1)

[Claims] A forward and backward transmission is provided on each of the left and right turning shafts, and a forward and backward interlining rotation lever is provided to operate these transmissions f to perform anti-reverse movement and interlining rotation. Left and right steering levers that turn on and off regardless of the speed are installed in front of the driver's seat. A transmission device for a mobile work vehicle characterized by being equipped with the following features: