JPH0643562Y2 - Multi-plate friction type transmission mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-plate friction type transmission mechanism provided in, for example, an agricultural tractor, and more specifically, at one end portion in a rotation axis center direction of a rotary drum into which a friction plate is engaged and fitted, The present invention relates to a multi-plate friction type transmission mechanism in which a transmission gear having a tooth bottom portion having a diameter smaller than a drum diameter is integrally connected, and a rotating body that supports a friction plate facing the friction plate is provided inside and outside the rotating drum.

[Conventional technology]

A conventional transmission mechanism is, for example, Japanese Patent Laid-Open No. 58-5.
As shown in 7549 publication, while forming a spline shaft portion at the end of the rotary drum, forming a spline fitting hole that fits the spline shaft portion at the inner peripheral portion of the transmission gear, these There is a structure in which the gears are fitted (see FIG. 2 in the above publication) or a structure in which the transmission gear and the rotary drum are bolted at a plurality of points (see FIG. 3 in the above publication).

[Problems to be solved by the device]

However, in the above conventional structure, in the manufacturing process, outer peripheral gear cutting processing of the transmission gear, inner peripheral side spline hole processing, and rotary drum side spline shaft processing are necessary, or
There has been a problem in that the number of man-hours for processing and assembling is large, such as requiring a troublesome bolt connection work, which leads to cost increase.

Moreover, in the above-mentioned spline fitting structure, when machining the spline shaft on the rotary drum side, a machining gap is required between the rotary drum and the transmission gear. In other words, the processing start part of the spline shaft has to have an oblique shape so that the groove is shallow and gradually deepens at first, and the bite is insufficient in the shallow groove part, so this part is the same as the rotary drum and the transmission gear. There will be a gap between them, and in reality there will be wasted space between them.

Further, in the bolt connection structure, since the transmission gear is bolt-connected to the shaft support side wall portion of the rotary drum, the thickness of the side wall portion and the hydraulic piston that is an example of the rotating body are However, there is a problem in that a space for projecting the head of the bolt is required and the dimension along the axial direction becomes large.

An object of the present invention is to provide a multi-plate friction type transmission mechanism capable of reducing the manufacturing man-hours, cost reduction, and size reduction by rational structural improvement.

[Means for Solving the Problems]

According to a characteristic configuration of the present invention, in the multi-plate friction type transmission mechanism described at the beginning, the gear width of the transmission gear is set to be larger than a required transmission width, and the outer periphery of the transmission gear at the end on the rotary drum side is set. In the gear part, an internal gear-shaped fitting hole formed at the end of the rotary drum is externally fitted and attached, and is in contact with the side surface of the transmission gear of the rotating body.
The action and effect are as follows.

[Action]

In other words, it has a structure in which the fitting hole of the rotary drum is externally fitted to a part of the transmission gear for transmission, and the remaining portion of the transmission gear can be transmitted to the outside.

In the manufacturing process, gear cutting for the transmission gear and formation of the fitting hole for the rotary drum are performed, and then, the rotary drum and the transmission gear may be driven and fitted.

Moreover, since the transmission gear and the rotary drum are separately manufactured, the surface treatment work such as quenching of the transmission gear can be easily performed by using a single component having a shape that makes it easy to process the required treatment area.

Furthermore, since the rotating drum is integrated by using the outer peripheral gear part of the transmission gear, the driving force from the outside is transmitted to the rotating drum with the same diameter as it is, so the transmission torque does not increase and the coupling strength is minimized to the required minimum. In order to receive the pressing force of the friction plate, by making the rotating body arranged in contact with the inner wall portion of the transmission gear side contact the side surface of the transmission gear, As in the conventional structure, a space for disposing the shaft supporting side wall portion of the rotary drum and the head portion of the connecting bolt is not necessary, and the dimension along the rotary shaft core direction can be shortened accordingly.

[Effect of device]

Therefore, while obtaining a good transmission condition,
Compared to the conventional structure, it is possible to reduce the number of parts processing man-hours and to simplify the assembly work to reduce costs, and it is possible to reduce the size along the axis of rotation that tends to increase in size. It was

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a part of a transmission structure of an agricultural tractor using a multi-plate friction type transmission mechanism (A) according to the present invention. This transmission structure is configured to transmit the rotational power of the first rotating shaft (1) to the second rotating shaft (2) through the multi-plate friction type transmission mechanism (A) in an intermittently operable manner.

In the multi-disc friction type transmission mechanism (A), a tooth bottom portion has a drum diameter (drum diameter) at one end portion in a rotation axis direction of a rotary drum (4) into which a plurality of friction plates (3) for friction transmission are engaged and fitted. D) A transmission gear (5) having a smaller diameter than that of D) is integrally connected. Then, the drive gear (6) externally fitted to the first rotating shaft (1) and the transmission gear (5) are interlockingly connected in a constantly engaged state.

The transmission gear (5) is freely fitted around the second rotating shaft (2) and is fitted onto the second rotation shaft (2) in a fixed position in the axial direction, and the rotating drum (5) is integrally connected to the transmission gear (5). On the inner side of 4), a plurality of inner side friction plates (7) are alternately arranged between the rotary drum side friction plates (3) as viewed in the axial direction. The friction plate (7) has a second rotating shaft (2).
The spline is fitted to the outer periphery of the friction transmission rotating body (8) which is integrally rotated.

A pressing member (9) is spline-fitted to the opening side of the rotating drum of the second rotating shaft (2) so as to be slidable in the axial direction, and the pressing member (9) is attached to the shift fork (10). ), And presses the overlapping portions of the friction plates (3) and (7). All the friction plates (3) and (7) are pressure-bonded, and the frictional force causes the rotational power of the rotary drum (4) to be transmitted to the second rotary shaft (2) via the rotary body (8). .

One end of the rotating body (8) is brought into contact with the side surface of the transmission gear (5), and the friction plates (3) and (7) are moved to the other end side by the pressing operation by the shift fork (10). It is designed to be effectively received and supported.

As shown in FIG. 2, the transmission gear (5) has a gear width (L1) more than a gear width (L2) having a strength necessary for transmitting the drive gear (6) in an articulated manner. In the large set region, a stepped gear (11) having a diameter smaller than that of the meshing portion with the drive gear (6) is formed at the end portion on the rotary drum side. Then, an internal gear-like fitting hole (12) formed at the outer end of the rotary drum (4) is driven into this stepped gear (11) as an outer peripheral gear portion of the transmission gear (5) and fitted. There is. That is,
The stepped gear (11) side is formed in a slightly tapered shape, and the rotary drum (4) is driven in and fitted to the transmission gear (5).
And the rotary drum (4) are integrated.

In the processing of the transmission gear (5), an outer diameter cutting process before gear cutting is performed, in particular, a normal gear cutting process may be performed after the step is cut together. Further, the rotary drum (4) only needs to have the fitting hole (12) formed by broaching, and the assembling work can be simplified by only driving, instead of the troublesome bolt connecting work.

[Another embodiment]

As shown in FIG. 3, an engaging peripheral groove (13) is formed on the outer periphery of the gear portion and the groove (13) is formed instead of forming the stepped portion on the transmission gear (5) as in the above embodiment. A locking ring (14) for positioning is engaged with the locking ring (13), and the fitting hole (12) of the rotary drum (4) and one end of the transmission gear (5) are driven and fitted and connected. It may be one.

It should be noted that reference numerals are added to the claims of the utility model for convenience of comparison with the drawings, but the invention is not limited to the structure of the accompanying drawings by the entry.

[Brief description of drawings]

1 is a sectional view, FIG. 2 is an exploded perspective view, and FIG. 3 is a sectional view of another embodiment of the multi-plate friction type transmission mechanism according to the present invention. (3), (7) ... friction plate, (4) ... rotating drum,
(5) …… Transmission gear, (8) …… Rotating body, (12) ……
Mating hole, (L1) …… Gear width.

Claims (1)

[Scope of utility model registration request] 1. A transmission gear (5) having a tooth bottom portion having a diameter smaller than the drum diameter is integrally connected to one end portion of a rotary drum (4) in which a friction plate (3) is fitted and fitted therein, in the direction of an axis of rotation. A multi-plate friction type transmission mechanism comprising a rotating body (8) for supporting a friction plate (7) facing the friction plate (3) on the inner side of the rotating drum (4), Transmission gear (5)
The gear width (L1) of the transmission gear is set to be larger than the required transmission width, and the outer peripheral gear portion of the end portion of the transmission gear (5) on the rotary drum (4) side is attached to the end portion of the rotary drum (4). A multi-plate friction type transmission mechanism in which the formed fitting hole (12) in the form of an internal gear is externally fitted and is in contact with the side surface of the transmission gear (5) of the rotating body (8). .