JPH0315569B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for preventing erroneous operation of a PTO transmission mechanism for a PTO shaft that is provided to be removably attached to an agricultural tractor for rotationally driving a working machine. In particular, the present invention relates to an erroneous operation prevention device for a PTO transmission mechanism that can prevent the erroneous use of two types of PTO shafts that use different rotational speeds.

[Prior Art] Conventionally, there has been known a device for preventing erroneous operation of this type of PTO transmission mechanism, which is described in Japanese Patent Application Laid-Open No. 136075/1983.

Therefore, what is stated in the above bulletin is PTO
The power transmission path is equipped with a speed change mechanism, and this speed change mechanism is configured to change speed via a pusher provided at the center of the second speed change shaft, and by selectively replacing and connecting the PTO shaft, the pusher changes accordingly. The system is configured to operate as follows.

[Problem to be solved by the invention] The above-mentioned conventional PTO transmission mechanism erroneous operation prevention device has the following features:
When one of the two types of PTO shafts is installed on the second gear shift shaft, the gears of the attached PTO shaft are changed, but the side that is not in use is
The PTO shaft must be stored elsewhere. Therefore, selecting this storage location is troublesome, and there is a risk of forgetting the storage location or losing the stored PTO shaft when not in use.

Therefore, a technical problem arises that must be solved in order to select an appropriate storage location and to be able to safely and securely store the PTO shaft that is not in use.The present invention solves this problem. The purpose is to

[Means for Solving the Problems] This invention was proposed to achieve the above object, and includes a PTO transmission mechanism provided in the PTO power transmission path, and a system for changing the speed of this PTO transmission mechanism via a regulating section. By selectively replacing and joining two PTO shafts for high-speed rotation and low-speed rotation, the PTO is configured to operate in two types, high-speed rotation and low-speed rotation, depending on the restriction section. In the device for preventing erroneous operation of the transmission mechanism, an engagement groove is provided at the tip of the connecting joint provided on one side of the PTO shaft, and one of the PTO shafts is further provided with an engaging groove at the tip of the connecting joint. On the other hand, the other PTO shaft is provided with a protruding restriction part, and the connecting joint part is the restriction part, and the engagement groove and the restriction part are on the inside, and the PTO shaft is installed in the transmission case. It is configured so that it can be installed in the fitting hole, and furthermore, the unused PTO shaft can be inserted and removed from the fitting hole of the transmission case.
In order to enable this operation only when the operating section of the PTO transmission mechanism is in the neutral position, a locking body is fitted into the engagement groove provided at the tip of the PTO shaft so that it can freely move in and out of the transmission case. When engaged, the transmission mechanism is configured to be disengaged when the transmission mechanism is in a neutral position, and further, the PTO
A push arm that rotates when the respective regulating portions of the shaft come into contact is fixed to a pin that is rotatably fitted to the change cover, and the other end of the pin is provided with a support portion of the operating lever. A regulating plate disposed on one side is fixedly installed, and the regulating plate is configured to be rotated by the rotational movement of the push arm.
It is an object of the present invention to provide a device for preventing erroneous operation of a PTO transmission mechanism, which is characterized in that it is formed so that only the transmission corresponding to the shaft can be changed.

[Function] This invention provides a PTO drive shaft for high-speed rotation where rotation is transmitted by a PTO transmission mechanism.
Either the PTO shaft or the low-speed rotation PTO shaft is connected, and the gear shift corresponding to the connected PTO shaft is performed, and the side that is not used is
It is the same as before that the gear change corresponding to the PTO shaft is prevented from being performed by the regulating operation of the regulating part, but the PTO shaft on the side that is not used is installed in the fitting hole provided in the transmission case. and stored. At this time, the connecting joint part of the PTO shaft is fitted into the fitting hole, and the engaging groove and the regulating part provided at the tip of the connecting joint part are fitted inside, and , the locking pin fitted into the end engagement groove so as to be freely protrusive and retractable on the transmission case side protrudes and fits into the end engagement groove.
PTO shaft pullout is prevented. Furthermore, when the PTO transmission mechanism is in the neutral position, the locking pin sinks into the transmission case and comes out of the engagement groove provided in the PTO shaft.
Therefore, the PTO shaft can be inserted and removed only when the PTO transmission mechanism is in the neutral position.

In other words, the PTO shaft on the side that is not in use is installed in the fitting hole provided in the transmission case and stored, but the regulating part provided at the tip of this PTO shaft presses the push arm and rotates it to a predetermined position. start and stop. At this time, the regulation plate interlocked with the push arm is placed in a position where other PTO shafts (for example, high-speed rotation PTO shafts) that do not correspond to the stored PTO shaft (for example, low-speed rotation PTO shafts) can shift gears. It will rotate,
Therefore, only the speed change corresponding to the PTO shaft in use is possible.

[Example] Hereinafter, one embodiment of the present invention will be described in detail with reference to the attached drawings. For convenience of explanation, conventionally known technical matters will also be explained at the same time. In the diagram, 1 is
This is a PTO input shaft, and is provided so that the PTO input shaft 1 is driven by a prime mover via a PTO clutch, and the rotation of this PTO input shaft 1 is transmitted to a PTO drive shaft 2 by changing the speed via a PTO transmission mechanism. At the rear of this PTO drive shaft 2, there is a second joint 2a such as a spline boss that can be connected to a joint formed at the front of the PTO shaft, as described later.
Install as shown. And the PTO transmission mechanism is
Large and small diameter gears 3 and 4 are provided on the PTO input shaft 1, respectively, and the counter gear 5, which is loosely fitted on the PTO drive shaft 2, is the gear 3, and the counter gear 6 is the gear 3, which is loosely fitted on the PTO drive shaft 2.
are meshed with the gears 4, respectively, and the internal gear 8a of the slide coupling 8 is meshed with the teeth of the hub 7 fitted to the PTO drive shaft 2, so that the shifter rod can be moved freely in the axial direction toward the transmission case 9. If a shifter oak 11 is fixedly attached to the shifter oak 10 and the slide coupling 8 that engages with the shifter oak 11 is moved, the internal gear 8a will be connected to the counter gear 5.
The internal gear 8a engages with the clutch teeth 5a of the counter gear 6, causing the PTO drive shaft 2 to rotate at high speed, and conversely, the internal gear 8a engages with the clutch teeth 6a of the counter gear 6, causing the PTO
The drive shaft 2 is provided to rotate at a low speed.

Then, prepare PTO shafts corresponding to each gear stage of the above-mentioned PTO transmission mechanism,
These PTO shafts can be fitted and connected to the joint part 2a of the PTO drive shaft 2, but the PTO shaft 12 for high-speed rotation shown in FIG. Cylinder 13
A connecting joint part 12a, such as a spline boss, which can be connected through a spline boss, and a joint part 12b, which can connect a universal joint shaft for driving an input shaft of a working machine (not shown), are provided at the rear. For example, a cylindrical regulating part 14 is protruded from the tip of 12a, and the rear part is supported by a bearing 17 on a bearing body 16 attached to the rear part of the transmission case 9 with bolts 15, as shown in FIG. The joint tube 13 is fitted into the joint part 2a of the PTO drive shaft 2, and a recessed part 2b is formed in the rear end of the PTO drive shaft 2.
The connecting joint part 12a of the PTO shaft 12 is fitted into the rear part of the joint cylinder 13, and the collar part 12c of the PTO shaft 12 is prevented from coming off by a retaining ring 18 inserted into the joint cylinder 13.

Also, the low speed PTO shaft 1 shown in Figure 6
9 uses the connecting joint part 19a as it is as the regulating part 20. Then, the connecting joint parts 12a or 19a of the PTO shaft 12 or 19 are fitted into the fitting holes 9a provided in the transmission case 9, and the flange part 12c is fitted.
Alternatively, 19c is provided so that it can be held down with a presser foot 21.

In addition, a regulating plate 24 is fixed to a pin 23 that is rotatably fitted to the change cover 22, and the control lever 25, which is swingable around the ball portion 25a fitted to the change cover 22, is engaged. The joint portion 25b is fitted into the guide groove 26 of the regulation plate 24, and then fitted into the engagement recess 11a of the shifter oak 11, and the pin 23
A spring 28 is stretched between the regulating plate 24 and the change cover 22 to keep the push arm 27 fixedly attached to the regulating portion 14 or 20 of the PTO drive shaft 12 or 19 at all times.

The guide groove 26 consists of a neutral groove N, a high speed groove H, and a low speed groove L as shown in FIG.
When the pushing arm 27 is engaged with the regulating part 14, the regulating plate 27 is held in the position shown in FIG. 25 can be operated in low gear,
When the engaging portion 25b moves toward the high-speed groove H or the neutral groove N, the engaging portion 25b moves toward the shifter oak 1.
Since it is disengaged from the engagement recess 11a of No. 1, it becomes impossible to operate the high speed gear.

Also, when the low-speed PTO shaft 19 is fitted into the fitting hole 9a as shown in Fig. 4A, the regulating part 2
0, the pushing arm 27 holds the regulating plate 24 in the position shown in FIG. When the engagement portion 25b moves toward the low speed groove L or the neutral groove N, the engagement portion 25b is disengaged from the engagement recess 11a of the shifter fork 11, so that it cannot be operated to a low speed gear.

In FIG. 1, reference numeral 29 is a travel input shaft driven by the engine via a main clutch (not shown). It is possible to operate the gear shift by holding the lever.

Further, the PTO shafts 12 and 19 are provided with engagement grooves 31 or 32, respectively, and the locking pin 33 inserted into the locking pin hole 9b of the transmission case 9 is inserted into the spring 34.
PTO shaft 12 or 19 installed depending on
When the shifter rod 10 is in the neutral position as shown in FIG. As a result, the locking pin 33 escapes from the engagement groove 31 or 32, and at this time, the PTO shaft 12 or 19 is formed so that it can be pulled out from the fitting hole 9a.

Therefore, the PTO shaft 12 or 19 can be pulled out only when the PTO transmission mechanism is in the neutral position, so even if the engine is rotating,
The PTO shaft does not rotate, so it is safe.

Further, in FIG. 1, reference numeral 35 is a positioning ball that is biased by a spring 36 and can be fitted into the high/low speed and neutral positioning holes 10b to 10d of the shifter rod 10.

The device for preventing erroneous operation of the PTO transmission mechanism of this invention is
Can be freely connected to and removed from the PTO drive shaft 2 driven via the PTO transmission mechanism
Two PTO shafts are formed for each rotation speed used, and the one PTO shaft that is not used is provided so that it can be attached to the transmission case 9, and in this attached state, the regulating part formed on the PTO shaft is connected to the PTO shaft. This is done by the operation part of the transmission mechanism.
The PTO shaft is configured to prevent switching to the operating speed, so if it is not used,
By attaching the PTO shaft to the transmission case 9, the restriction section provided on the PTO shaft can directly prevent the PTO transmission mechanism from switching to the operating speed of the PTO shaft. be.

[Effects of the Invention] As described in detail in the above embodiment, the present invention allows the PTO shaft on the unused side to be securely attached to the fitting hole provided in the transmission case for storage, and to store the stored PTO shaft. Shaft, that is, the side that is not in use.
Incorrect PTO gear shifting corresponding to the PTO shaft is prevented, and furthermore, the PTO shaft on the unused side is
Since the PTO shaft can be inserted and removed only when the PTO transmission mechanism is in the neutral position, it is safe because the PTO shaft does not rotate even while the engine is rotating.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Figure 1 is a longitudinal cross-sectional side view of the main part of the mission case, and Figure 2 is a side view of the main part of the mission case.
A vertical sectional side view showing the connected state of the PTO shaft, Figures 3A and 4A are longitudinal sectional front views of main parts showing the attached state of the unused PTO shaft, and Figure 3B is A-A in Figure 3A. Linear view, Figure 4 B is B- in Figure 4 A
A view taken along the line B, FIG. 5 is an explanatory view of the main parts of FIG. 3A, and FIG. 6 is an explanatory view of the main parts of FIG. 4A. Symbol explanation, 1... PTO input shaft, 2a... Joint part, 2b... Recessed part, 2... PTO drive shaft, 3, 4... Gear, 5... Counter gear, 5
a, 6a...Clutch tooth, 7...Hub, 8...Slide coupling ring, 8a...Internal tooth gear, 9...
Mission case, 9a... Fitting hole, 9b... Locking pin hole, 10... Shifter rod, 10a... Relief hole, 10b to 10d... Positioning hole, 11...
Shifter oak, 11a...Engagement recess, 12,1
9...PTO shaft, 12a...Connection joint,
12b...Joint part, 12c, 19c...Brim part, 1
3...Joint tube, 14, 20...Regulation part, 15...
Bolt, 16...Bearing body, 17...Pairing,
18... Retaining ring, 21... Presser foot, 22... Change cover, 23... Pin, 24... Regulating plate, 2
5... Operating lever, 25a... Ball portion, 25b...
Engaging portion, 26...Guide groove, 27...Push arm, 28, 34, 36...Spring, 29...Travel input shaft, 30...Travel shift lever, 31, 32...
Engagement groove, 33...locking pin, 35...positioning ball, H...high speed groove, L...low speed groove, N...neutral groove.

Claims (1)

[Claims] 1 Equipped with a PTO transmission mechanism in the PTO power transmission path,
This PTO transmission mechanism is configured to change speed via a regulating part, and the two PTO shafts for high-speed rotation and low-speed rotation are selectively exchanged and joined, so that high-speed rotation and low-speed rotation can be performed according to the regulation part. In a device for preventing erroneous operation of a PTO transmission mechanism configured to operate in two types of rotation, an engagement groove is provided at the tip of a connecting joint provided on one side of the PTO shaft; The PTO shaft is further provided with a regulating part protruding from the tip of the connecting joint part, and on the other hand,
The other PTO shaft has the connecting joint part as a regulating part, and the engagement groove and the regulating part are on the inside,
The PTO shaft is configured so that it can be attached to a fitting hole provided in the transmission case, and furthermore, an unused PTO shaft is attached to the fitting hole provided in the transmission case.
In order to allow the PTO shaft to be inserted and removed only when the operating section of the PTO transmission mechanism is in the neutral position, a shaft is inserted into the engagement groove provided at the tip of the PTO shaft so that it can freely protrude and retract from the transmission case side. When the fitted locking body is engaged, it is configured to be disengaged when the transmission mechanism is in a neutral position, and further rotated by contact with each restriction portion of the PTO shaft. The push arm is fixed to a pin rotatably fitted to the change cover,
Furthermore, a regulation plate disposed below the support of the operating lever is fixed to the other end of the pin, and the regulation plate is configured to be rotated by the rotational movement of the push arm. An erroneous operation prevention device for a PTO transmission mechanism, characterized in that it is formed so that only the transmission corresponding to the PTO shaft in use is possible.