JP2004060823A - Pto shaft rotational frequency detecting device for working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device capable of accurately and easily detecting a rotational frequency of a PTO shaft in a working vehicle wherein a driving shaft and the PTO shaft are horizontally and pivotally supported between a partition wall of a transmission case and a rear cover, and a PTO transmission intervenes between the shafts. <P>SOLUTION: A detection plate 26 rotating integrally with the PTO shaft is fitted onto the PTO shaft 19 on a position adjacent to the rear cover 24. A rotational frequency sensor 27 facing the detection plate 26 is detachably attached on the rear cover 24 from a rear part. Thus, the rotational frequency of the PTO shaft is detected. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for detecting a rotation speed of a PTO shaft provided in a working vehicle.
[0002]
[Prior art]
In a working vehicle such as an agricultural tractor, various kinds of agricultural work are performed by a work machine mounted on the body. In order to perform these works properly, a PTO shaft (power take-out shaft) for driving the work machine is required. It is necessary to adjust the rotation speed to an appropriate rotation speed depending on the type of the working machine and the work content.
Therefore, conventionally, as a method for detecting and displaying the rotational speed of the PTO shaft, the rotational speed of the PTO transmission is detected in addition to detecting the rotational speed of the engine, and the rotational speed of the PTO shaft is indirectly calculated. JP-A-57-137861 is known.
There is also known one in which the rotation speed of a PTO shaft is directly detected by a rotation speed detection sensor and displayed.
[0003]
[Problems to be solved by the invention]
However, in the former of the above prior arts, it is necessary to separately provide a detector for detecting the shift position of the transmission, in addition to a sensor for detecting the number of revolutions of the engine. Was complicated.
In the latter case, it is difficult to secure a space on the transmission case for mounting the detector and to maintain the detector.
An object of the present invention is to improve these disadvantages of the related art.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a work in which a drive shaft and a PTO shaft are supported substantially in parallel between a partition wall of a transmission case and a rear cover, and a PTO transmission is interposed between the two shafts. In a vehicle, a detection plate is fitted on the PTO shaft so as to rotate integrally with the PTO shaft near the rear cover, and a rotation speed detection sensor facing the detection plate is detachably mounted on the rear cover from the rear. To detect the rotational speed of the PTO shaft.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall perspective view of an agricultural tractor which is a working vehicle according to the present invention, wherein 1 is a traveling body of the tractor, 2 and 2 are front wheels, 3 is rear wheels, and 4 is a hood covering an engine 5 described later. is there.
A cabin 6 covers a driver's seat, and various operating tools for driving operation are arranged in the cabin 6.
[0006]
Next, FIG. 2 is a transmission block diagram of an agricultural tractor provided with the rotation speed detecting device of the present invention, in which power from an engine 5 enters a drive shaft (drive shaft) 9 via a main clutch 8. After being shifted to a desired speed via the main transmission 10, the forward / reverse transmission (shuttle transmission) 11, the ultra-low speed transmission 12, and the auxiliary transmission 13, the transmission is shifted from the pinion shaft 14 via the rear wheel differential 15. And transmitted to the rear wheel 3.
[0007]
On the other hand, the power to the front wheels 2 is separated from the pinion shafts 14, passes through a two-wheel drive / four-wheel switching shaft 16, a front wheel speed increasing device 17 for making a small turn, and the like. It is transmitted to.
The power from the drive shaft 9 is also transmitted to a PTO shaft 19 at the rear of the machine body for driving a work machine mounted on the traveling machine body 1 via a PTO transmission device 20. The rotation speed of the PTO shaft 19 can be appropriately changed according to the working machine to be mounted or the work content.
[0008]
Next, FIG. 3 is an exploded view of the PTO transmission 20, and the PTO transmission 20 is built in a portion near the rear of the transmission case 22.
A partition 23 that separates the rear wheel differential device 15 and the like incorporated near the front of the transmission case 22 from the rear cover 24 that is detachably attached to the rear end of the transmission case 22 with bolts. The drive shaft 9 and the PTO shaft 19 are supported substantially in parallel via front and rear bearings 25, 25,..., Between the two shafts 9, 19, three forward rotations and one reverse rotation. Since the PTO transmission 20 constituted by a constant-mesh type gear transmission is interposed, the power of the drive shaft 9 is shifted to an appropriate rotation speed suitable for the work machine mounted on the machine body 1 and then the PTO shaft 19 to transmit power from the PTO shaft 19 to the working machine.
9a, 9b, 9c are first, second (reverse), and third speed drive gears provided on the drive shaft 9, and 19a, 19b, 19c, and 19d are loosely fitted on the PTO shaft 19. The gears are driven gears of high speed, second speed, reverse rotation, and third speed. C1 is a 1-2 speed switching clutch, and C2 is a third speed / reverse switching clutch.
[0009]
In the transmission case 22, a disc-shaped detection plate 26 is fitted at a position close to the rear cover 24 so as to rotate integrally with the PTO shaft 19, and the rear cover 24 includes: A mounting hole is made in the vicinity of the outer periphery of the detection plate 26, and a magnetic rotation speed detection sensor 27 is inserted into the mounting hole from the rear, and is removably mounted with a bolt 28 to rotate the PTO shaft 19. The number is configured to be detectable.
Here, the positioning and fixing of the detection plate 26 in the front-rear direction is performed using the stepped portion 19 e of the PTO shaft 19 and the inner ring of the bearing 25.
An upper portion 29 is a reverse shaft of the PTO transmission 20, and an idle gear 29a is loosely fitted on the reverse shaft 29.
[0010]
FIG. 4 is a rear view of a main part of the transmission case 22, in which a detection plate 26 substantially at the center has a gear-like outer peripheral portion 26a and a PTO shaft at the center. There is provided a hole 30 through which 19 passes.
Notch portions 30a are further provided at two upper and lower portions of the hole portion 30, and protrusions 30b, 30b formed in the center of the notch portion 30a are provided with upper and lower grooves 19f provided on a stepped portion 19e of the PTO shaft 19. , 19f to prevent rotation, and the detection plate 26 rotates integrally with the PTO shaft 19.
The rotation speed detection sensor 27 has its tip 27a (see FIG. 3) facing the gear-shaped portion 26a of the detection plate 26, and thereby the magnetic fluctuation caused by the rotation of the detection plate 26 and the passage of the tooth 26b. Is detected and input to a microcomputer 32 described later to detect the rotation speed of the PTO shaft 19.
The detection plate 26 is formed of a magnetic metal plate.
[0011]
FIG. 5 is a control block diagram for displaying the PTO axis rotation speed and the like on a liquid crystal monitor (LCD), FIG. 6 is a diagram showing a display example of the liquid crystal monitor (LCD), and FIG. The front views of the instrument panels incorporating ()) are shown respectively.
First, in FIG. 5, the microcomputer 32 is connected at its input side to an engine speed detecting sensor 33 and the speed detecting sensor 27 of the PTO shaft 19, and an instrument panel 34 (see FIG. ), A monitor switch 35 such as a PTO rotation speed, a vehicle speed, a TRIP meter, and a clock is connected.
A liquid crystal monitor (LCD) 36 for displaying data selected by the monitor changeover switch 35 on the instrument panel 34 is connected to the output side.
[0012]
That is, FIG. 6 shows a specific display example of the liquid crystal monitor (LCD) 36. When the driver selects a button of a desired item of the monitor changeover switch 35 and presses it with a finger, the data of these items is displayed. Is displayed on a liquid crystal monitor (LCD) 36. When the PTO button is pressed, the number of rotations of the PTO shaft is displayed, for example, 1000 rpm at a large value in the lower part, and the vehicle speed is displayed at a small value in the upper part. You.
Further, FIG. 7 shows an instrument panel 34 provided in front of the driver's seat of the tractor. In particular, the above-mentioned monitor changeover switch 35 is provided at the lower right side, and an analog meter for displaying the engine speed at the center of the right side. A liquid crystal monitor (LCD) 36 is disposed in the section.
[0013]
The PTO shaft rotation speed detecting device for a working vehicle according to the present invention is configured as described above. The driver starts the engine 5 and attaches a working machine (not shown) to the rear portion of the body 1 to perform work. To a field or the like where
Before starting the agricultural work or the like, it is necessary to adjust the rotation speed of the working machine in advance. In this case, first, a PTO speed change lever (not shown) provided on the side of the driver's seat is operated, and the above-described operation is performed. A desired gear is selected from among the first, second, third, and reverse rotations of the PTO transmission 20, and a rough rotation speed of the working machine is set.
[0014]
Next, when the driver presses the “PTO rotation” button of the monitor changeover switch 35 on the instrument panel 34 with a finger to know the actual PTO shaft rotation speed, the PTO shaft rotation speed is displayed on the liquid crystal monitor (LCD) 36. Then, the driver operates the fuel control lever (not shown) of the engine 5 to increase or decrease the rotation speed of the engine 5 so that the rotation speed of the PTO shaft 19 is adjusted to an appropriate rotation before starting the work. Good.
When the rotational speed of the engine 5 fluctuates due to the load during the work, the fuel control lever is operated again while looking at the liquid crystal monitor (LCD) 36 for the PTO shaft rotational speed. Alternatively, the rotation may be adjusted appropriately according to the work content.
[0015]
In the present invention, a detection plate 26 is provided integrally with the final PTO shaft 19 that transmits power to the work machine, and a PTO shaft rotation speed detection sensor 27 is mounted on the rear cover 24 of the transmission case 22. Therefore, it is not necessary to detect the shift position of the PTO shift position 20 in particular, and the rotation speed of the PTO shaft 19 can be accurately detected.
Further, since the detection plate 26 is formed of a flat plate in the vicinity of the rear cover 24, the distance between the detection plate 26 and the PTO shaft rotation speed detection sensor 27 can be easily measured. Even in the case of maintenance such as when the detection sensor 27 breaks down, the PTO shaft rotation speed detection sensor 27 attached to the rear cover 24 can be easily attached and detached from the rear part of the machine, which is excellent in maintainability.
In addition, the detection plate 26 allows the PTO shaft rotation speed sensor 27 to be disposed at an arbitrary position on the rear cover 24 at an arbitrary radius around the PTO shaft 19 with respect to the PTO shaft 19. Problems such as disconnection of the detection sensor 27 when the detection sensor 27 comes into contact with the PTO shaft 19 or a working machine or the like can be prevented beforehand.
[0016]
Further, as the fixing of the detection plate 26 to the PTO shaft 19, the positioning in the axial direction can be performed by clamping the stepped portion 19 a of the PTO shaft 19 and the bearing 25. The transmission can be performed by engaging the groove 19f provided in the stepped portion 19a of the PTO shaft 19 with the projections 30b, 30b of the detection plate 26, and the detection plate 26 can be arranged in a very small space. The detection plate 26 as a PTO shaft rotation speed detection device can be easily mounted in the transmission case 20 without largely changing the configuration of the transmission 22.
[0017]
【The invention's effect】
As described above, according to the present invention, the drive shaft 9 and the PTO shaft 19 are supported between the partition 23 of the transmission case 22 and the rear cover 24 in a substantially parallel manner, and the PTO transmission is provided between the two shafts 9 and 19. In the working vehicle having the PTO shaft 20, the detection plate 26 is fitted on the PTO shaft 19 so as to rotate integrally with the PTO shaft 19 in the vicinity of the rear cover 24, and the detection plate 26 is mounted on the rear cover 24. 26 is mounted detachably from the rear so as to detect the rotation speed of the PTO shaft 19, so that the final PTO is always maintained regardless of the state of the PTO speed change position 20. The rotation speed of the shaft 19 can be accurately detected. The rear cover 24 attached to the rear of the transmission case 22 has a PTO shaft rotation detection Since the support 27 is mounted from the rear detachably maintenance upon failure of the PTO shaft speed sensor 27 is also easily performed, it is possible from aft body.
[0018]
Further, since the detection plate 26 rotates integrally about the PTO shaft 19, the PTO shaft rotation speed detection sensor 27 can be arranged at an arbitrary position about the PTO shaft 19 of the rear cover 24, Problems such as disconnection can be solved beforehand.
[Brief description of the drawings]
FIG. 1 is an overall perspective view of an agricultural tractor according to the present invention.
FIG. 2 is a transmission block diagram.
FIG. 3 is a development view of a PTO transmission portion.
FIG. 4 is a rear view of a main part of the transmission case.
FIG. 5 is a control block diagram for displaying a PTO axis rotation speed on a liquid crystal monitor (LCD).
FIG. 6 is a display example of a liquid crystal monitor (LCD).
FIG. 7 is a front view of an instrument panel incorporating a liquid crystal monitor (LCD).
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Traveling body 5 Engine 9 Drive shaft 19 PTO shaft 20 PTO transmission 22 Transmission case 23 Partition wall 24 Rear cover 26 Detection plate 27 PTO shaft rotation speed detection sensor 34 Instrument panel 35 Monitor changeover switch 36 Liquid crystal monitor (LCD)

Claims (1)

A drive shaft (9) # and a PTO shaft (19) are supported between the partition wall (23) of the transmission case (22) and the rear cover (24) substantially in parallel, and the two shafts (9), (19) are supported. In a working vehicle having a PTO transmission (20) interposed therebetween, a detection plate (26) is rotated on the PTO shaft (19) integrally with the PTO shaft (19) near the rear cover (24). In addition, a rotation speed detection sensor (27) facing the detection plate (26) is detachably attached to the rear cover (24) from the rear to detect the rotation speed of the PTO shaft (19). A PTO shaft rotation number detecting device for a working vehicle, characterized in that:

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