JPH1024746A - Transmission for working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To brake a mid PTO shaft during a state of not driving the mid PTO shaft by linking an inertial idling preventive braking device and a PTO clutch mechanism interlockingly so that the inertial idling preventive bracking device is operated in the case of operating into a rear PTO shaft driving state or a neutral state. SOLUTION: An inertial idling preventive braking device G is provided on a front part of an intermediate transmission shaft 34 of a mid PTO drive train MD so as to be able to brake a mid PTO shaft 14. PTO clutch mechanism C1 is provided on a PTO transmission shaft 33 so as to be able to perform linear shift operation into four positions that are a rear PTO shaft driving position, a neutral position, a both PTO shaft driving position and a mid PTO shaft driving position. In such constitution, in case a PTO switching lever is in the neutral position or in the PTO shaft driving position, the inertial idling preventive braking device G continues to operate regardless of depression of a clutch pedal so as to brake the mid PTO shaft 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction in which a working machine is mounted on the lower abdomen and the rear of a traveling vehicle, and the working machine mounted on the lower abdomen prevents inertial idling.

[0002]

2. Description of the Related Art In a transmission configured to drive a working machine disposed in a lower part and a rear part of a working vehicle, a technique in which an inertial anti-spin brake device is arranged in a drive train for driving the working machine in a lower part is known. It is known. For example, the technique of Japanese Utility Model Publication No. 7-15784. The inertial anti-spin brake device in this technology has a power take-out case in which a mid-PTO shaft is arranged on the lower surface of the transmission case, and a mid-PTO driving clutch mechanism and an inertial anti-spin brake device are provided on the mid-PTO shaft in the power take-off case. In this configuration, the inertial anti-skid brake device is operated when the mid-PTO clutch lever is operated to the "off" side and when the clutch pedal is depressed.

[0003]

In the prior art, the mid-PTO driving clutch and the rear PTO driving clutch are separately provided, and the on / off operation is performed by separate levers. When the power to the shaft is cut off, or only when the clutch pedal is depressed, the inertial anti-spin prevention brake device does not operate.For example, when switching from driving the mid PTO shaft to driving the rear PTO shaft, Even though the clutch pedal is once depressed, the mid-PTO shaft that has been braked may idle again due to the inertia of the work machine because the depressed time is short. In addition, since the link mechanism that links the inertial anti-spin brake device and the clutch mechanism is provided outside the transmission case, it is necessary to take care not to interfere with other link mechanisms. Occasionally, it may cause malfunctions.

[0004]

Means for Solving the Problems In order to solve the above problems, the present invention is configured as follows. A transmission having a mid-PTO shaft for driving a work machine mounted on a lower abdomen of a vehicle and a rear PTO shaft for driving a work machine mounted on a rear part of the vehicle, wherein inertia anti-spin which can brake the mid-PTO shaft is provided. A brake device is provided, and a mid-PTO shaft drive state, a rear PTO shaft drive state,
A PTO clutch mechanism capable of showing each state of a shaft driving state and a neutral state in which both PTO shafts are not driven;
When the clutch mechanism is operated in at least one of a rear PTO shaft drive state and a neutral state, the inertial anti-spin brake device and the PTO clutch mechanism are linked so that the inertial anti-spin brake device operates. It was done. Further, the inertial anti-spin brake device,
Further, a link mechanism for interlocking and linking the inertial anti-spin brake device and the clutch mechanism is provided in a transmission case accommodating the transmission.

[0005]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the structure of an embodiment of the present invention. 1 is an overall side view of a work vehicle, FIG. 2 is a front perspective view of a transmission case, FIG. 3 is a side developed view of the transmission, FIG. 4 is an enlarged cross-sectional view of an upper part of FIG. 3, and FIG. , FIG.
1 is a skeleton diagram of the transmission, FIG. 7 is a partial side sectional view of the inertial anti-spin brake device and the restraint device, FIG. 8 is a front sectional view of the restraint device, FIG. 9 is a perspective view of the restraint device, and FIG.
0 to 13 are explanatory diagrams of the operation of the check device.

Referring to FIG. 1, the entire configuration of a working vehicle equipped with the transmission of the present invention will be described. The engine E is housed in a hood 1 in front of the fuselage, a dashboard 2 is arranged at the rear of the hood 1, and a handle 3 is arranged above the dashboard 2. Step 4 for getting on and off is arranged at the lower part of the dashboard 2.
, A clutch pedal 5 is arranged on the left side, and a brake pedal (not shown) is arranged above the right side. A seat 6 is disposed above the rear of the step 4, and a main transmission lever 7, an auxiliary transmission lever 8, and a PTO switching lever 9 are disposed beside the seat 6.

A transmission according to the present invention is disposed below the seat 6, and the transmission accommodates a traveling transmission and a PTO transmission in a transmission case formed by joining a front case 10 and a rear case 11. I have. On the front surface of the front case 10, an input shaft 12, a front wheel drive shaft 13, and a mid PTO shaft 14 project forward, and the input shaft 12
Is a clutch case 1 with respect to the crankshaft of the engine E.
The main clutch 39 and the transmission shaft 16 are connected in an interlocked manner. The power output from the front wheel drive shaft 13 is transmitted to the input shaft 19 protruding from the front axle case 18 via the universal joint 17, and drives the front wheels 20 supported on both sides of the front axle case 18. Reference numeral 22 denotes a power steering cylinder. The mid-PTO shaft 14 is linked via a universal joint 23 to an input shaft 26 protruding from a gear box 25 of a mower 24. The mower 24 is suspended by an elevating device (not shown) so as to be able to ascend and descend in the lower abdomen space between the front wheel 20 and the rear wheel 21.

An axle 27 protrudes from both left and right sides of the rear part of the rear case 11 to support the rear wheel 21. A hydraulic arm having a pair of lift arms 30 facing the rear of the machine is provided on the upper surface of the rear case 11. A case 29 is placed. Lower links 31 and a drawbar hitch 32 are attached to the lower rear end of the rear case 11. A work machine can be mounted on the lift arm 30, the lower link 31, and the top link (not shown) so as to be able to move up and down, or a tow work machine can be mounted on the drawbar hitch 32. A rear PTO shaft 36 protrudes rearward from the rear surface of the rear case 11 so as to be able to drive a work machine mounted on the rear of the machine body.

As shown in FIGS. 2 and 3, the transmission case has a front case 10 having a front wall 10a and an open rear end, and a partition wall 11a inside the front case 10 and having a front end opened. An input shaft 12 is supported on an upper portion of a front wall 10a of the front case 10; and a front and rear center portion of the front wall 10a and the rear case 11 is provided. Between the provided partition wall 11a, the PTO transmission shaft 3 is provided.
3, traveling third shaft 43, traveling fourth shaft 44, intermediate transmission shaft 34
The mid-PTO shaft 14 is rotatably suspended in parallel with each other along the longitudinal direction of the fuselage via bearings. Then, as shown in FIG. 5, when viewed from the front, the input shaft 12 is arranged at the upper center of the mission case, and the PTO
The transmission shaft 33 and the traveling third shaft 43 are juxtaposed at substantially the same level in the left-right direction, and the traveling fourth shaft 44 is positioned below the traveling third shaft 43.
, And the intermediate transmission shaft 34 and the mid-PTO shaft 14 are arranged in this order from one side to the left and right obliquely downward. The joint surface of the transmission case is the mid PTO shaft 1
4 is defined so as to be separated and joined to the front case 10 and the rear case 11 on a virtual plane orthogonal to the boundary. The front case 10 is integrally formed with a bulging portion 10b having a front wall for supporting the front end of the mid-PTO shaft 14 and having an open rear end. Bulges 10b and 11 having a rear wall that supports
b is integrally formed. When the front case 10 and the rear case 11 are joined to each other, the two bulging portions 10b and 11b are joined to each other at their open portions to form the inside thereof as a closed space,
The mid PTO shaft 14 is rotatably accommodated and supported, and extends obliquely downward from the lower abdomen of the front case 10 and the rear case 11 so that the mid PTO shaft 14 can be positioned on one of the left and right sides as described above. It has become. In addition, by forming a storage portion for the drawbar hitch 32 outside the bulging portions 10b and 11b, the minimum ground clearance can be increased.

Further, the partition wall 1 provided on the rear case 11
1a is a front and rear partition inside the mission case,
A front chamber F is formed in a front case 10 in front of 1a,
A traveling transmission, and a mid PT described below of the PTO transmission.
The rear compartment R is formed between the partition wall 11a and the rear wall 11c of the rear case 11 to accommodate the O drive train MD and the PTO clutch mechanism C1, and accommodates the rear PTO drive train RD and the differential device D. I have. The rear PTO drive train RD has a rear PTO input shaft 35 laid in the front-rear direction on an upper portion between the partition wall 11a and the rear wall 11c, and a gear 35a is provided at a rear portion of the rear PTO input shaft 35, It is configured to always mesh with a gear 37 fixed to a rear PTO shaft 36 protruding rearward from 11c.

Power is transmitted to the front end of the input shaft 12 from the engine E via the main clutch 39 and the transmission shaft 16 as described above. At the rear end of the input shaft 12, an input gear 45 is fixedly provided in the front chamber F. The input gear 45
Is always meshed with a gear 41 a on a hollow traveling first shaft 41 loosely fitted to the outer periphery of the traveling third shaft 43 so as to be relatively rotatable. As shown in FIG. 4, three gears 41a, 41b and 41c are integrally formed on the outer periphery of the traveling first shaft 41.

A gear 41a on the traveling first shaft 41 is always meshed with a high-speed gear 46 loosely fitted on a hollow traveling second shaft 42 parallel to the traveling first shaft 41, and a gear 41b is connected to the traveling second shaft 41. A boss 49 that rotates integrally with 42 is spline-fitted to engage with a low-speed gear 47 that is slidable in the axial direction, and a gear 41c always meshes with a PTO transmission gear 50 loosely fitted on the PTO transmission shaft 33. The PTO transmission gear 50 is formed to be wide, and the reverse gear 5 is loosely fitted on the traveling second shaft 42.
1 is always engaged. The above is the configuration of the first transmission unit of the traveling transmission.

The main shift lever 7 is configured to be able to shift to three positions of "high-speed position", "low-speed position", and "reverse position". The main transmission lever 7 and the low-speed gear 47 are linked so that the gear 47 slides on the boss 49. When the main shift lever 7 is shifted to the "high-speed position", the internal teeth of the low-speed gear 47 mesh with the engaging elements 52 of the high-speed gear 46, and the power of the input gear 45 is changed from the gear 41a to the high-speed gear 46 to the low-speed gear. 47 → boss 49 → travel second shaft 42.

When the main shift lever 7 is shifted to the "low speed position", the low speed gear 47 meshes with the gear 41b, and the power of the input gear 45 is changed from the gear 41a to the gear 41b.
b → low speed gear 47 → boss 49 → traveling second shaft 42. When the main transmission lever 7 is shifted to the “reverse position”, the internal teeth of the low-speed gear 47
And the power of the input gear 45 is changed to the gear 41a →
Gear 41c → PTO transmission gear 50 → reverse gear 51 → low speed gear 47 → boss 49 → traveling second shaft 42
The O transmission gear 50 serves as an idle gear in the reverse gear train.

Each of the hollow traveling first shaft 41 and the traveling second shaft 42 is installed on the front side of each of the traveling third shaft 43 and the traveling fourth shaft 44 supported by the transmission case. The first transmission portion described above is formed on the rear side of each of the traveling fourth shaft 44 and the traveling third shaft 43.
The second transmission portion is configured between the wheels 4 and 43 as follows.
That is, gears 55, 56, 57, 58 of different diameters are fixed on the rear outer periphery of the traveling third shaft 43, and splines are formed on the rear outer periphery of the traveling fourth shaft 44, and two sliding members are formed. The dynamic gears 60 and 61 are engaged slidably in the axial direction. The sliding gear 60 is provided with external teeth 60a that can mesh with the gear 58 and external teeth 60b that can mesh with the gear 57. The sliding gear 61 has an external tooth that can mesh with the gear 56. There are provided teeth 61a and internal teeth 61b meshable with a gear 54 engraved on the outer periphery of the rear end of the traveling second shaft 42.
The gear 54 is always meshed with the gear 55.

The above-mentioned auxiliary speed change lever 8 is constructed so as to be able to shift to a "first speed position", a "second speed position", a "third speed position", or a "fourth speed position". The sliding gears 60 and 61 move in conjunction with
The auxiliary transmission lever 8 and the sliding gears 60 and 6 are slid so as to slide upward.
1 is linked. When the sub-shift lever 8 is shifted to the "first speed position", the external teeth 60a of the sliding gear 60 mesh with the gear 58, and the speed of the traveling second shaft 42 increases from the gear 54 → the gear 55 → the gear 58 → the external gear. While passing through 60a, the speed is greatly reduced and transmitted to the fourth traveling shaft 44.

When the sub shift lever 8 is shifted to the "second speed position", the external teeth 60b of the sliding gear 60 mesh with the gear 57, and the speed of the traveling second shaft 42 is reduced from the gear 54 → the gear 55 → the gear 57. → The traveling fourth shaft 4 is decelerated while passing through the external teeth 60b.
It is conveyed to 4. When the sub-shift lever 8 is shifted to the "third speed position", the engagement of the sliding gear 60 with the gears 58 and 57 is released, and the external teeth 61a of the sliding gear 61 mesh with the gear 56, so that the second travel The speed of the shaft 42 is
→ Gear 55 → Gear 56 → Slightly reduced speed while passing through the external teeth 61 a is transmitted to the fourth traveling shaft 44. When the sub-transmission lever 8 is shifted to the “fourth speed position”, the internal teeth 61 of the sliding gear 61 are shifted.
b meshes with the gear 54, and the speed of the traveling second shaft 42 is transmitted directly from the gear 54 to the internal teeth 61b to the traveling fourth shaft 44. As described above, since the traveling speed change position is configured by connecting the first transmission portion capable of obtaining high speed, low speed, and reverse and the second transmission portion capable of obtaining four-speed shifting in series, the traveling transmission device as a whole is A total of 12 gears, ie, 8 gears on the forward side and 4 gears on the reverse side, are possible.

A pinion 4 is provided at the rear end of the traveling fourth shaft 44.
4a is formed and meshed with the ring gear 62 of the differential device D. The differential device D is configured such that the left and right differential yoke shafts 27a and 27a shown in FIG. 6 are differentially coupled, and the left and right axles 27 and 27 are driven from the differential yoke shafts 27a and 27a via reduction gear trains. Have been.
The front end of the fourth travel shaft 44 penetrates the front wall 10a of the front case 10 and protrudes outward, and the rear portion of the front wheel drive shaft 13, which is arranged so that the rotation axes thereof coincide with each other, is loosely fitted therein. I support it. The front wheel drive shaft 13 is the front case 10
And is rotatably supported and accommodated in a support case 13a mounted on the front wall 10a of the vehicle.

A clutch slider 63 is spline-fitted slidably on the outer periphery of the rear end of the front wheel drive shaft 13. When the clutch slider 63 is engaged with the front end of the fourth traveling shaft 44, the front wheel 20 and the rear wheel 21 are simultaneously driven to be in a four-wheel drive state, and when not engaged with the fourth traveling shaft 44, a two-wheel drive state in which only the rear wheels 21 are provided. The clutch slider 63 is operated so as to be shifted by a four-wheel drive selection lever (not shown) provided in the work vehicle.

Next, the PTO transmission will be described. A clutch tooth 50a is formed on one side of the PTO transmission gear 50 loosely fitted on the front part of the PTO transmission shaft 33,
A clutch body 64 is spline-fitted to a front part of the O transmission shaft 33, and one side of the clutch body 64 has clutch teeth 6
4a, and the PTO transmission gear 50
And the clutch teeth 50a and 64a are engaged with each other in one direction, and are disengaged in the reverse rotation, so that the one-way clutch C2 constitutes the one-way clutch C2 and the PTO transmission gear 50 and the PTO transmission shaft. 33 is interlockingly connected.

A mid-PTO input gear 66 is loosely fitted on the middle part of the PTO transmission shaft 33, and P
A boss 67 fixed to the TO transmission shaft 33 is arranged,
The front end of the rear PTO input shaft 35 is loosely fitted and supported so that the rear end of the transmission shaft 33 coincides with the rear end of the transmission shaft 33. The mid PTO input gear 66 is always meshed with the first intermediate gear 73. The first intermediate gear 73 is loosely fitted between the gear 51 at the rear of the traveling second shaft 42 and the external teeth 54 via a bearing 72, and is fixedly mounted on the intermediate transmission shaft 34. 74
And the second intermediate gear 74 is connected to the mid PTO shaft 1
4 always meshes with the gear 75 fixed on the
A mid-PTO drive train MD for transmitting power to the shaft 14 is configured. Thus, as shown in FIG. 3, the mid-PTO drive train MD (mid-PTO input gear 6) for transmitting power to the mid-PTO shaft 14
6, first intermediate gear 73, second intermediate gear 74, gear 75)
Is located in the front chamber F in the transmission case and is located between the first transmission section (main transmission) and the second transmission section (sub transmission), and is therefore unrelated to the rear PTO drive train RD. In addition, the rear PTO shaft 14 can be arranged at an optimal position in the lower abdomen of the transmission case, and the transmission transmission and the PTO transmission are rationally accommodated in the transmission case to obtain a compact configuration. Can be In addition, since the first intermediate gear 73 is disposed thereon by using the shaft of the traveling system, a more compact configuration can be achieved.

On the PTO transmission shaft 33, a PTO clutch mechanism C1 is configured as follows. That is, mid PT
An engaging element 69 is formed on one side of the O input gear 66, an engaging element 70 is also formed on one side of the rear PTO input shaft 35, and a spline is formed on the outer periphery of the boss 67 to form a single clutch shifter 71. Are spline-fitted slidably in the axial direction. The PTO switching lever 9 is located at four positions: a "rear PTO shaft drive position (R)", a "neutral position (N)", a "both PTO shaft drive position (B)", and a "mid PTO shaft drive position (M)". The clutch shifter 71 is configured so that the shift operation can be performed linearly.
The PTO switching lever 9 and the clutch shifter 71 are linked so as to slide on the boss 67.

When the PTO switching lever 9 is shifted to the "Rear PTO shaft driving position (R)", the clutch shifter 71 slides rightward on the drawing from the position shown in FIG. And the PTO transmission shaft 33
Is transmitted from the boss 67 to the rear PTO input shaft 35 via the clutch shifter 71, and the gears 35a
7, only the rear PTO shaft 36 is driven. PTO
When the switching lever 9 is shifted to the "neutral position (N)", the clutch shifter 71 is placed at the position shown in FIG.
The engaging element 70 of the TO input shaft 35 and the mid PTO input gear 6
6 does not engage with any of the engaging members 69 of the rear PTO shaft 3.
6. The mid PTO shaft 14 is not driven. When the PTO switching lever 9 is shifted to the "both PTO shaft drive position (B)", the clutch shifter 71 slides to the left from the position shown in FIG. Simultaneously engages with the engaging element 69 of the gear 66,
The power from the O transmission shaft 33 is transmitted from the boss 67 via the clutch shifter 71 to the mid PTO input gear 66 and the rear PT
It is simultaneously transmitted to the O input shaft 35, and both the mid PTO shaft 14 and the rear PTO shaft 36 are driven. When the PTO switching lever 9 is further shifted to the "Mid PTO shaft driving position (M)", the clutch shifter 71 further slides to the left in the drawing, and engages only with the engaging element 69 of the mid PTO input gear 66.
The power from the PTO transmission shaft 33 is transmitted from the boss 67 to the mid PTO input gear 66 via the clutch shifter 71, and only the mid PTO shaft 14 is driven.

When the PTO switching lever 9 is shifted to the "neutral position (N)" and the "rear PTO shaft driving position (R)", the mid PTO shaft 14 does not rotate.
An inertial anti-spin brake device G as shown in FIG. 6 is provided on the front of the intermediate transmission shaft 34 of the mid-PTO drive train MD so that braking can be applied to the mid-PTO shaft 14. Then, the PTO switching lever 9 is set to “both PTs”.
In the “O-axis drive position (B)” and the “mid-PTO axis drive position (M)”, a check mechanism is provided so as not to operate the inertial anti-spin brake device G.

The inertial anti-spin brake system G is constructed as follows. That is, both ends of the intermediate transmission shaft 34 are rotatably supported via bearings between a lid 76 provided below the front wall 10a of the front case 10 and a lower portion of the rear case 11 of FIG. A hollow cylindrical brake chamber 10c is formed on the front wall 10a of the
are engaged with and arranged alternately on the inner periphery of the inner periphery of c and the outer periphery of the front end of the counter shaft 34, and pressing plates 77 are provided on both front and rear sides of the friction plates 76.
· 77 is arranged, and the pressing plate 77 on one side and the lid 7
A spring 79 is interposed between the pressing plate 7 and the pressing plate 7 on the other side.
The tip of the pressing arm 80 is in contact with 7.

The restraining mechanism of the inertial anti-spin brake system G is configured as shown in FIGS. That is, a support shaft 81 that is substantially perpendicular to the lower part of the intermediate transmission shaft 34 is supported by both side walls of the front case 10 on both sides thereof, and is rotatably mounted in the transmission case so as to be rotatable around the left and right axes. doing. One end of the support shaft 81 extends to the outside of the case, and an arm 84 is fixed thereto. One end of a rod 85 is connected to the arm 84 via an arc-shaped long hole 84a shown in FIG. The front end of the rod 85 is connected to an arm 86 provided at the rotation base of the clutch pedal 5. A cylindrical shaft 82 is fixed to the outer periphery of the support shaft 81,
The pressing arm 80 is provided on the cylindrical shaft 82 so as to extend upward, while the contact arm 83 is provided so as to extend rearward.

Below the support shaft 81, a restraining shaft 88 in a direction substantially perpendicular to the support shaft 81 is supported at its both ends by the bulging portion 10b of the front case 10 and the bulging portion 11b of the rear case 11, respectively. It is horizontally mounted inside the transmission case so as to be rotatable around the axis. A fan-shaped restraining cam 87 is formed by adhering a small diameter portion 87a and a large diameter portion 87b to the rear outer periphery of the restraining shaft 88, and the tip of the contact arm 83 is brought into contact with the restraining cam 87. I have. An arm 89 is fixed to a front portion of the restraining shaft 88, and one end of a connecting rod 90 is pivotally connected to the arm 89, and the other end of the connecting rod 90 is located inside a side wall of the front case 10 as shown in FIG. It extends upward along the side surface and is pivotally connected to one end of a bell crank 91. The bell crank 91 is fixed to the inner end of an operation shaft 92 rotatably supported on the side wall of the front case 10, and the outer end of the operation shaft 92 projects outward from the front case 10 to mount the arm 93. The arm 93 is fixed, and the arm 9 a provided at the rotation base of the PTO switching lever 9 is linked via a rod 94. The other end of the bell crank 91 has a pin 91a.
The pin 91a is connected to the front case 10 and the rear case 1
1 and is inserted into a fitting hole 95a provided on the outer periphery of a PTO switching shaft 95 slidable in the front-rear direction. A shift fork 96 is fixed to the rear end side of the PTO switching shaft 95, and the shift fork 96 is attached to the clutch shifter 7.
1 is fitted.

In FIG. 9, when the PTO switching lever 9 is rotated in the front-rear direction, a bell crank 91 is rotated around an operation shaft 92, and one end of the bell crank 91 is operated to rotate a check shaft 88 via a connecting rod 90. At the same time as the distraction cam 87 is displaced, the other end is connected to the PTO switching shaft 9 via the pin 91a.
5 is slid in the front-rear direction, and the shift fork 96 shifts the clutch shifter 71 (not shown) to any of the four positions described above.

When the PTO switching lever 9 is "Mid PTO"
When the shaft drive position (M) ”and the“ both PTO shaft drive position (B) ”are in place, as shown in FIGS. 10 and 11, the contact arm 83 is located on the small diameter portion 87a of the restraining cam 87,
When the O switching lever 9 is at the "neutral position (N)" or "rear PTO shaft driving position (R)", the contact arm is placed on the large-diameter portion 87b of the restraining cam 87 as shown in FIGS. The shape of the restraint cam 87 and the amount of rotation of the restraint shaft 88 are set so that the position 83 is located. When the contact arm 83 is positioned on the large diameter portion 87b of the restraining arm 87, the pressing arm 80 is retracted from the pressing plate 77 when the contact arm 83 is positioned on the small diameter portion 87a of the restraining cam 87. Presses the pressing plate 77 so that the inertial anti-spin brake device G operates.
1 rotation operation amount, the contact arm 83 and the pressing arm 80
Has set the length.

Prior to switching the PTO switching lever 9 to each of the four positions, the main clutch is disengaged by depressing the clutch pedal 5 and the power transmission from the engine E to the input shaft 12 is cut off. Here, as shown in FIG. 9, the clutch pedal 5 is released and the PTO switching lever 9 is released as shown in FIG. 9 and the PTO switching lever 9 is released. Is located at the "neutral position (N)" or the "rear PTO shaft drive position (R)" shown in FIG.
When the contact arm 83 is located above and the inertial anti-spin brake device G is operating, one end of the rod 85 linked to the clutch pedal 5 is connected to the long hole 8 provided in the arm 84.
4a is located at the start end (right end in the figure). When the clutch pedal 5 is depressed to switch to another position of the PTO switching lever 9, one end of the rod 85 only moves freely toward the end (the left end in the drawing) in the long hole 84 a, and the depression of the clutch pedal 5 is performed. No force is transmitted to arm 84.
That is, when the PTO switching lever 9 is in the "neutral position (N)" or the "rear PTO shaft drive position (R)", the inertial anti-skid brake device G always operates regardless of the depression of the clutch pedal 5. The mid PTO shaft 14 is configured to be braked.

The arc length of the long hole 84a is determined when the depression of the clutch pedal 5 is released and
7, the contact arm 83 is located on the small diameter portion 87a, and the pressing arm 80 is retracted from the pressing plate 77, that is,
When the PTO switching lever 9 is in the “mid-PTO shaft drive position (M)” or the “both PTO shaft drive position (B)” and the operation of the inertial anti-skid brake device G is released, the rod 85 The length is set such that one end is located at the end thereof, whereby the PTO switching lever 9 is set to the “Mid PTO shaft drive position (M)” or “the both P
When the clutch pedal 5 is depressed in the “TO shaft drive position (B)”, the force is applied to the arm 84 and the support shaft 8.
1 and transmitted to the pressing arm 80 via the pressing plate 7
7 to activate the inertial anti-spin brake device G to apply a braking force to the mid-PTO shaft 14 which is to continue idling due to inertia from the work implement.

In such a configuration, when the PTO switching lever 9 is set to the "middle PTO shaft driving position (M)", the bell crank 91 is swung via the rod 94 and the arm 93, and the PTO switching shaft 95 and the shift fork 96, the clutch shifter 71 is connected to the mid PTO shaft 14 as described above.
At the same time, the restraining shaft 88 is rotated via the connecting rod 90 and the arm 89,
The restraining cam 87 is rotated as shown in FIG.
When the contact arm 83 is located on the upper side 7a, and the depression of the clutch pedal 5 is released and the main clutch 39 is connected, the contact arm 83 falls into the small-diameter portion 87a,
When the pressing arm 80 is separated from the pressing plate 77, the operation of the inertial anti-spin brake device G is released, and the mid P
The TO shaft 14 can be driven. When the PTO switching lever 9 is switched to the "both PTO shaft drive position (B)", the restraining cam 87 is rotated as shown in FIG. 11 and the contact arm 83 is positioned above the small diameter portion 87a. Then, the operation of the inertial anti-spin brake device G is released as described above, and the mid PTO shaft 14 and the rear PTO shaft 3 are released.
6 can be driven.

The PTO switching lever 9 is set to "Mid PTO".
The clutch pedal 5 is depressed before switching from the "axis drive position (M)" / "both PTO shaft drive position (B)" to the "neutral position (N)" / "rear PTO shaft drive position (R)". At this time, while the support shaft 81 rotates in a direction in which the pressing arm 80 is pressed against the pressing plate 77 to operate the inertial anti-spin braking device G, the contact arm 83
Is lifted upward to retract from the check cam 87. When the PTO switching rail 9 is in the "neutral position (N)", the restraint cam 87 is positioned as shown in FIG. 12, and when the "rear PTO shaft drive position (R)", the restraint cam 87 is positioned as shown in FIG.
In any case, since the contact arm 83 is located above the large diameter portion 87b of the restraining cam 87, the contact arm 83 remains in the lifted state, and the pressing arm 80 is
7, the operation of the inertial anti-spin brake system G continues, and the mid-PTO shaft 14 cannot rotate. And
When the depression of the clutch pedal 5 is released in this state,
The connecting rod 85 slides in the long hole 84a of the rotating arm 84 and returns to the start end side. This long hole 84a allows the depressing operation of the clutch pedal 5 when disconnecting and driving the rear PTO shaft 36, while maintaining the inertia. The operation of the anti-spin brake system G is continued.

[0034]

As described above, the present invention has the following advantages. That is, a transmission including a mid-PTO shaft for driving a working machine mounted on a lower abdomen of a vehicle and a rear PTO shaft for driving a working machine mounted on a rear portion of the vehicle, wherein an inertia capable of braking the mid-PTO shaft is provided. In addition to providing an anti-spin brake device,
A PTO clutch mechanism capable of displaying each state of a TO axis drive state, a rear PTO axis drive state, a both PTO axis drive state, and a neutral state where both PTO axes are not driven is provided, and the PTO clutch mechanism is in a rear PTO axis drive state. And the PTO clutch mechanism is interlocked with the inertial anti-skid brake device so that the inertial anti-skid brake device is operated when operated in at least one of the neutral state and the one PTO switching mode. When only the lever is operated and the mid-PTO is not driven, the inertial anti-spin prevention brake device is always activated and the mid-PTO shaft is braked, so there is no need to perform complicated lever operations, and the main clutch is turned on and off. Regardless of this, when the operation of the inertial anti-spin prevention brake device is configured to continue, the PTO clutch mechanism is driven in the rear PTO shaft drive state. Before switching from the state to the rear PTO shaft drive state or the neutral state, the mid PTO shaft can be braked when the main clutch is disengaged, and the braking state is continued even if the main clutch is returned to the on-going side thereafter. Therefore, the mid PTO shaft can be reliably stopped when not in use. Further, since the inertial anti-spin brake device and the link mechanism for interlocking and linking the inertial anti-spin brake device and the clutch mechanism are provided in the transmission case housing the transmission, the link mechanism is not exposed to the outside, and Malfunctions due to biting, intrusion of water or mud, and the like are eliminated, and the inertial anti-skid brake device can be operated stably.

[Brief description of the drawings]

FIG. 1 is an overall side view of a work vehicle.

FIG. 2 is a front perspective view of a transmission case.

FIG. 3 is a side elevational view of the transmission.

FIG. 4 is an enlarged sectional view of the upper part of FIG.

FIG. 5 is a front sectional view of the transmission.

FIG. 6 is a skeleton diagram of a transmission.

FIG. 7 is a partial side sectional view of the inertial anti-spin brake device and the check device.

FIG. 8 is a front sectional view of the restraint device.

FIG. 9 is a perspective view of the restraint device.

FIG. 10 is an operation explanatory view of the check device.

FIG. 11 is an explanatory diagram of the operation of the check device.

FIG. 12 is a diagram illustrating the operation of the restraint device.

FIG. 13 is an explanatory diagram of the operation of the restraint device.

[Explanation of symbols]

 C1 PTO clutch mechanism G Inertia anti-spin brake device 5 Clutch pedal 9 PTO switching lever 12 Input shaft 14 Mid PTO shaft 36 Rear PTO shaft 39 Main clutch 87 Traction cam

Claims (4)

[Claims] 1. A transmission comprising a mid-PTO shaft for driving a work machine mounted on a lower abdomen of a vehicle and a rear PTO shaft for driving a work machine mounted on a rear portion of the vehicle, wherein the mid-PTO shaft is braked. In addition to providing a possible inertial anti-spin brake device, a PTO clutch mechanism capable of displaying each state of a mid-PTO shaft drive state, a rear PTO shaft drive state, both PTO shaft drive states, and a neutral state in which both PTO shafts are not driven is provided. And the PTO clutch mechanism is a rear PTO
The inertial anti-skid brake device and the PT are operated so that the inertial anti-skid brake device is operated when operated in at least one of the shaft driving state and the neutral state.
A transmission for a working vehicle, wherein the transmission is linked to an O-clutch mechanism. 2. The transmission case containing the transmission, wherein the inertial anti-spin brake device and a link mechanism for linking the inertial anti-spin brake device and the PTO clutch mechanism are interlocked. Work vehicle transmission. 3. A PTO transmission shaft to which power from an engine is transmitted via a main clutch, and a mid PTO shaft to which rotation from the PTO transmission shaft is transmitted to drive a work machine mounted on a lower abdomen of the vehicle. A rear PTO shaft for driving a working machine mounted on a rear part of the vehicle, the transmission including an inertial anti-skid brake device capable of braking a mid PTO shaft, and activating when the main clutch is disengaged. And a PTO clutch mechanism capable of displaying each state of a mid PTO shaft driving state, a rear PTO shaft driving state, both PTO shaft driving states, and a neutral state in which both PTO shafts are not driven. When the clutch mechanism is operated in at least one of the rear PTO shaft drive state and the neutral state, the inertial idle In order to continue operation of the anti-spin brake device, the inertial anti-skid brake device and the PTO
A transmission for a work vehicle, wherein the transmission is linked to a clutch mechanism. 4. An inertial anti-spin brake device, and a link mechanism for interlocking and linking the inertial anti-spin brake device, the PTO clutch mechanism, and the main clutch.
The transmission of a work vehicle according to claim 3, wherein the transmission is housed in a transmission case accommodating the transmission.