JP4750385B2 - Power transmission device to work machine in traveling work machine - Google Patents

Description

  The present invention relates to a device for transmitting power to various working machines such as a tiller connected to a rear part thereof in a traveling working machine such as a tractor used for agricultural work or a wheel loader used for civil engineering work.

  In general, in the above-described traveling work machine such as a tractor or a wheel loader, power may be transmitted to various working machines such as a tiller that is detachably connected thereto. A PTO shaft that transmits power from an engine mounted on the traveling working machine is provided on the mounted mission case so as to project from the PTO shaft to various working machines.

In this case, in the conventional traveling work machine, for example, as described in Patent Document 1 and the like, the PTO shaft, the power transmission mechanism to the PTO shaft, and the power transmission to the PTO shaft are turned on. The clutch mechanism that is turned off is assembled to the transmission case.
JP 7-117500 A

  However, according to this conventional configuration, when the traveling work machine does not require the PTO shaft, the traveling working machine must be manufactured in a form in which the PTO shaft or the like is not assembled to the traveling working machine. Moreover, in the traveling work machine in which the PTO shaft or the like is not assembled, there is a problem that the PTO shaft or the like cannot be assembled later.

  In addition, the PTO shaft, a power transmission mechanism to the PTO shaft, and a clutch mechanism for turning on / off the power transmission to the PTO shaft are assembled to the transmission case in the traveling case. Due to the configuration, there is also a problem that maintenance such as disassembly repair and parts replacement for these PTO shafts is troublesome.

  This invention makes it a technical subject to provide the power transmission device to the working machine which eliminated these problems.

In order to achieve this technical problem, a first aspect of the present invention provides a traveling case that is supported by wheels and mounted with an engine, and a transmission case is mounted on the traveling transmission mechanism inside the transmission case. In the traveling working machine configured to transmit to the wheel via, a bracket body is detachably attached to the transmission case, and a PTO shaft for power transmission to the working machine detachably attached to the traveling machine body the provided, one for supporting the PTO shaft to the bracket body, the bracket body, and the power input clutch shaft from the engine to the PTO shaft, a hydraulic clutch for oN · OFF operation of the power transmission to the PTO shaft mechanism and the a structure in which a hydraulic clutch mechanism provided hydraulic pump and the hydraulic switching valve switches, said bracket body rear plate and the front plate A clutch shaft of the hydraulic clutch mechanism is provided between the rear plate and the front plate, and the clutch shaft is rotatably supported on a rear end of the PTO input shaft provided on the front plate and the rear plate, The hydraulic pump is attached to the front plate, the hydraulic switching valve is provided on the rear plate, the lubricating oil in the transmission case is pumped from a strainer by the hydraulic pump, and the hydraulic switching valve is connected to the hydraulic switching valve via a hydraulic line. It is configured to supply hydraulic oil from a hydraulic pump, and a brake mechanism is provided on a clutch shaft on which the hydraulic clutch mechanism is arranged. When the hydraulic clutch mechanism is turned off, the PTO shaft rotates. While operating to apply a brake, the brake is released when the hydraulic clutch mechanism is turned on for power transmission .

According to the first aspect of the present invention, the PTO shaft unit can be quickly mounted or removed , and maintenance such as repair and replacement of the PTO shaft can be extremely easily performed .

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, drawings when an embodiment of the present invention is applied to a tractor as a traveling work machine will be described.

  1 and 2 show a tractor 1, which supports a traveling machine body 2 with a pair of left and right rear wheels 4 as well as a pair of left and right front wheels 3 and is mounted on a front portion of the traveling machine body 2. The engine 5 is configured to travel forward by driving the rear wheels 4 and the front wheels 3, and on the upper surface of the traveling machine body 2, the control seat 6 and the front wheels 3 are moved left and right. A steering handle 7 adapted to be steered by moving is provided, and the rotation of the engine 5 is appropriately shifted at the rear part of the traveling machine body 2 and transmitted to the rear wheels 4 and the front wheels 3. A mission case 8 is installed.

  In this case, the rear wheels 4 are detachably attached to the transmission case 8 so as to protrude outwardly from the outer surface of the transmission case 8, and the outer side of the axle case 9. It is attached via a gear case 10 mounted so as to extend rearward at the end, and an axle 4 a for the rear wheels 4 is inserted into the axle cases 9.

  A gear case 11 that covers the drive shaft 5 a on the engine 5 side is attached to the rear side of the engine 5, and a gear train mechanism 12 in the gear case 11 is provided under the gear case 11 from the drive shaft 5 a. The main shaft 13 to which power is transmitted is provided so as to protrude rearward, and further, the rear surface of the gear case 11 is hydraulic to a working machine lifting mechanism 15 and a working machine hydraulic motor described below. A working hydraulic pump 14 is attached so as to be directly connected to the drive shaft 5a.

  A hydraulic working machine lifting mechanism 15 for lifting and lowering a working machine (not shown) such as a tiller connected to the rear part of the traveling machine body 2 can be attached to and detached from the upper surface of the rear part of the mission case 8. Installed on.

  Although not shown, between the hydraulic pump 14 and the working machine lifting mechanism 15, hydraulic fluid pressurized by the hydraulic pump 14 is supplied to the lifting mechanism 15 and discharged from the lifting mechanism 15. A hydraulic circuit configured to return the oil to the hydraulic pump 14 is provided. Of course, in this hydraulic circuit, the hydraulic switching for switching the lifting mechanism 15 into three stages of raising, lowering and lifting stop is provided. Needless to say, valves are provided.

  A telescopic power transmission shaft 19 having a universal shaft joint at both ends between the main shaft 13 projecting rearward from the gear case 11 and the input shaft 18 projecting forward from the front surface of the transmission case 8. And the rotation of the engine 5 is transferred from the drive shaft 5a to the input shaft 18 in the transmission case 8 through the gear train mechanism 12, the main drive shaft 13 and the power transmission shaft 19 in the gear case 11. Then, the transmission is appropriately shifted by a hydraulic / mechanical transmission mechanism (HMT) in the transmission case 8 and transmitted to the rear wheel 4 and both front wheels 3.

  As described below, the hydraulic / mechanical transmission mechanism (HMT) includes a transmission hydraulic pump 20 and a hydraulic continuously variable transmission mechanism (HST) 22 including a transmission hydraulic motor 21 operated by the hydraulic pump 20; A planetary gear mechanism 25 is used in combination with a gear-type transmission mechanism 24 that is speed-changed by a clutch 23.

  That is, as shown in FIG. 4, the transmission hydraulic pump 20 and the transmission hydraulic motor 21 are provided on the front surface of the transmission case 8 with a hydraulic pump input shaft 26 and a hydraulic motor output supported in the transmission case 8. While being attached so as to be connected to the shaft 27, the gear 28 fixed on the input shaft 18 is meshed with an input gear 30 that is rotatably fitted on a sun gear shaft 29 in the planetary gear mechanism 25. A plurality of planetary gears 32 are rotatably supported on a carrier 31 fixed to the input gear 30 via a support shaft 33, and each planetary gear 32 is fixed to the sun gear shaft 29. 34 and an inner ring gear 35 that is rotatably fitted on the sun gear shaft 29.

  Next, the gear 36 fixed to the inner ring gear 35 is engaged with a gear 37 fixed on the hydraulic pump input shaft 26 to rotate the shift hydraulic pump 20, while the output of the hydraulic motor The gear 38 fixed on the shaft 27 is engaged with the gear 39 fixed on the sun gear shaft 29, whereby the rotation of the transmission hydraulic motor 21 is transmitted to the sun gear shaft 29.

  On the other hand, a rear wheel propulsion shaft 40 is pivotally supported in the transmission case 8 and the rear end of the propulsion shaft 40 is connected to a conventionally known differential gear mechanism 41 for the two rear wheels 4. The rear wheel propulsion shaft 40 is configured to rotationally drive the rear wheels 4, while the gear 42 fixed on the propulsion shaft 40 is supported in the mission case 8 for propulsion for the front wheels. A gear 44 that is rotatably fitted on the shaft 43 is meshed, and between the front wheel propulsion shaft 43 and the conventionally known differential gear mechanism 45 for the front wheels 3, a universal shaft joint is provided at both ends. It is connected via a telescopic power transmission shaft 46 provided, and further, a clutch 47 is provided on the front wheel propulsion shaft 43, and the clutch 47 is fixed to the propulsion shaft 43. The rear wheel propulsion when operated to The two front wheels 3 driven to rotate by 40, the clutch 47, when operating so as not to fix the gear 44 relative to the propeller shaft 43, constituting the two front wheels 3 so as not to rotate.

  In the gear-type transmission mechanism 24, a gear 39 in which one small-diameter transmission gear 48 of two transmission gears 48 and 49 rotatably fitted on the rear wheel propulsion shaft 40 is fixed on the sun gear shaft 29. Further, the other large-diameter transmission gear 49 is engaged with the gear 50 fixed on the sun gear shaft 29, and the clutch 23 in the gear-type transmission mechanism 24 is propelled by the small-diameter transmission gear 48 in the clutch 23. When operated so as to be fixed to the shaft 40, the propulsion shaft 40 is rotated at a high speed, and the clutch 23 is fixed to the other large-diameter transmission gear 49 with respect to the propulsion shaft 40 by the clutch 23. When operated, the propulsion shaft 40 is rotated at a low speed, and the clutch 23 is fixed in the middle, that is, neither of the transmission gears 48, 49 is fixed to the propulsion shaft 40. When operated upright, the rotation transmission to the propulsion shaft 40 is interrupted, and further, between the high-speed rotation by one small-diameter transmission gear 48 and the low-speed rotation by the other large-diameter transmission gear 49, A hydraulic continuously variable transmission mechanism (HST) 22 is configured to change continuously.

  Further, as shown in FIGS. 3 and 5, the rear side surface 8 a of the transmission case 8 includes a PTO shaft 16 for a working machine (not shown) such as a tiller connected to the rear part of the traveling machine body 2. The unit 51 is detachably attached.

  The PTO shaft unit 51 includes a bracket body 52 configured in a front and rear box shape, and an opening formed in the rear side surface 8a of the transmission case 8 with respect to the rear side surface 8a of the transmission case 8. It attaches so that attachment or detachment is possible by fastening a plurality of bolts 52c so as to block 8b.

The PTO shaft 16 is pivotally supported on the bracket body 52 such that the PTO shaft 16 penetrates the rear plate 52a of the bracket body 52 and protrudes backward, while the front end of the bracket body 52 A PTO input shaft 53 constituted by a face plate 52b, that is, a side plate 52b inside the mission case 8 and a socket-like shaft joint 53a having a spline groove inside is rotatable in parallel with the PTO shaft 16. A rear end of a PTO shaft power transmission shaft 54 that is supported by a shaft and extends so as to extend rearwardly from the input shaft 18 in the transmission case 8 to a socket-like shaft joint 53a of the PTO input shaft 53. The ends are configured to be inserted and coupled simultaneously when the bracket body 52 is attached to the mission case 8.

Between the rear plate 52 a and the front plate 52 b of the bracket body 52, a clutch shaft 55 that extends rearward on the same axis as the input shaft 18 is provided between the rear end of the PTO input shaft 53 and the bracket body 52. The pinion gear 56 on the clutch shaft 55 is meshed with the gear 57 on the PTO shaft 16 so as to be rotatably supported by the rear plate 52a. The rotation of the direction is transmitted to the PTO shaft 16, and the PTO shaft 16 is configured to rotate clockwise as viewed from the rear. On the other hand, a clutch housing 58 is fitted to the clutch shaft 55, A multi-plate clutch 59 is provided between the clutch housing 58 and the input shaft 53, and the multi-plate clutch 59 is inserted into the cylinder chamber 60 in the clutch housing 58. By tightening the forward movement of the against the return spring 62 in the direction of the PTO input shaft 53 in the piston 61, and the power transmitted to the clutch shaft 55 from the PTO input shaft 53, the return spring 62 of the piston 61 The transmission of power from the PTO input shaft 53 to the clutch shaft 55 is cut off by loosening the tightening of the multi-plate clutch 59 by the backward movement due to.

  On the other hand, on the front plate 52b of the bracket body 52, that is, on the inner side surface of the transmission case 8, a hydraulic pump 63 for pumping the lubricating oil in the transmission case 8 from the strainer 63a is attached. By engaging the gear 64 on the pump shaft 63b with the gear 65 on the input shaft 53, the hydraulic pump 63 is driven to rotate, and the hydraulic pressure from the discharge side of the hydraulic pump 63 is supplied to the bracket body 52. The hydraulic switching valve 66 provided on the rear plate 52a is supplied through a hydraulic line 67, and the hydraulic switching valve 66 supplies the hydraulic pressure from the hydraulic pump 63 to the cylinder chamber 60 in the clutch housing 58. While supplying through a hydraulic passage 68 formed in the clutch shaft 55, A state in which the surface chamber is opened via the hydraulic passage 69 formed in the clutch shaft 55, and the supply of hydraulic pressure to the cylinder chamber 60 is stopped to open both the cylinder chamber 60 and the back chamber of the piston 61. It is configured to switch to the state to be performed.

  The clutch shaft 55 is interlocked with the reciprocating motion of the piston 61 via an interlocking pin 70 penetrating the clutch housing 58 in the axial direction, thereby opening the cylinder chamber 60 and returning the piston 61 to the return spring 62. When the power transmission of the multi-plate clutch 59 is turned off by reversing the rotation of the clutch, the rotation of the clutch shaft 55 is actuated to brake, and the piston 61 is moved forward to power the multi-plate clutch 59. A brake mechanism 71 is provided so as to release the brake when transmission is turned on.

  In this configuration, the PTO shaft unit 51 includes a bracket body 52 configured to close the extraction window 8b formed in the transmission case 8, and the PTO shaft 16 is pivotally supported on the bracket body 52. The body 52 is provided with a hydraulic multi-plate clutch 59 for the PTO shaft 16, a hydraulic pump 63 for the hydraulic multi-plate clutch 59, a hydraulic switching valve 66 for the hydraulic pump 63, and the like. Thus, the traveling working machine having the specification without the PTO shaft can be changed to the specification having the PTO shaft by attaching the PTO shaft unit 51 to the transmission case 8 thereafter, and the PTO shaft unit. A traveling work machine equipped with a PTO shaft equipped with 51 By the over scan 8 detaching the PTO shaft unit 51 can be changed arbitrarily specifications without PTO shaft.

  Needless to say, when the PTO shaft unit 51 is removed from the transmission case 8, the extraction window 8b in the transmission case 8 is closed with a separately prepared lid.

  Further, by mounting or removing the PTO shaft unit 51, it is possible to perform maintenance such as repair and replacement of the PTO shaft unit 51.

It is a side view which shows the tractor to which embodiment of this invention is applied. It is a top view of FIG. FIG. 3 is an enlarged side view taken along line III-III in FIG. 1. It is a skeleton diagram of power transmission. It is an enlarged vertical front view of a PTO shaft unit.

DESCRIPTION OF SYMBOLS 1 Tractor 2 Traveling machine body 3 Front wheel 4 Rear wheel 4a Axle 5 Engine 8 Transmission case 8a Rear side surface of transmission case 8b Opening 16 PTO shaft 51 PTO shaft unit 52 Bracket body 53 PTO input shaft 55 Clutch shaft 59 Multi-plate clutch 63 Hydraulic pressure Pump 66 Hydraulic switching valve

Claims (1)

A traveling work machine constructed by mounting a transmission case on a traveling machine body supported by wheels and mounting an engine, and transmitting the power of the engine to the wheels via a traveling transmission mechanism inside the transmission case. In
A bracket body is detachably attached to the transmission case, and includes a PTO shaft for power transmission to a work machine that is detachably mounted on the traveling machine body, and the bracket body pivotally supports the PTO shaft. In addition, a power input clutch shaft from the engine to the PTO shaft, a hydraulic clutch mechanism for turning on / off power transmission to the PTO shaft, a hydraulic pump and a hydraulic switching valve for switching the hydraulic clutch mechanism are provided. Structure,
The bracket body has a rear plate and a front plate, a clutch shaft of the hydraulic clutch mechanism is provided between the rear plate and the front plate, and the rear end of the PTO input shaft provided on the front plate and the rear plate The clutch shaft is rotatably supported,
The hydraulic pump is attached to the front plate, the hydraulic switching valve is provided on the rear plate, the lubricating oil in the transmission case is pumped from a strainer by the hydraulic pump, and the hydraulic switching valve is connected to the hydraulic switching valve via a hydraulic line. Configure to supply hydraulic oil of hydraulic pump,
A brake mechanism is provided on the clutch shaft on which the hydraulic clutch mechanism is arranged, and when the hydraulic clutch mechanism is turned off, the hydraulic clutch mechanism operates to brake the rotation of the PTO shaft. A power transmission device to a work machine in a traveling work machine, wherein the brake is released when the power transmission is turned on .

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