JPS5839253B2 - Kuratsuchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a driving rotary body and a driven rotary body so that they can be engaged and separated by relative movement in the direction of the axis of rotation, and are biased in the direction of engagement. A ring-shaped movable cam body rotatable around the axis is interposed between the rotating bodies, and
A manually operable locking device for fixing the rotation of the movable cam body around the axis is provided on the device fixing part, and a wave-shaped cam is provided on the opposing part of the movable cam body and the driven rotating body. The present invention relates to an improvement in a clutch configured to relatively rotate the movable cam body and the driven rotary body to separate the drive rotary body and the driven rotary body from each other.

This type of clutch has the characteristic that it can perform the required clutch disengagement operation smoothly and reliably with a weak operating force by using the driving force of the drive rotating body, but when the clutch is engaged,
There was a possibility that the following problem would occur.

In other words, the inclined surface between the trough and the peak of the wave-shaped cam used for clutch engagement and disengagement is normally aligned with the rotation axes of the driving rotor and the driven rotor so that the relative separation action is performed smoothly when the clutch is disengaged. Because the surface is inclined in a direction perpendicular to the direction parallel to the center direction, even if the fixing operation of the locking device to the movable cam body is released to put the clutch in the engaged state, the wave-shaped cam If the ridges are in slight occlusion, and the areas near the crests are slightly interlocked, the wave-shaped cams will not approach the occlusal side due to the frictional resistance effect via the inclined surfaces, and the clutch will not engage. There is a risk that the situation will not change.

As a solution to this problem, it is possible to make the urging force of a spring or the like that urges the driving rotor and the driven rotor in the direction of engagement sufficiently large, but in this case, a large urging force when the clutch is disengaged The driven rotary body and the driving rotary body must be moved relative to each other against the rotational force, which causes a problem of accelerated wear of the corrugated cam portion.

Therefore, in conventional buttons, one end of the drive rotor is brought into sliding contact with the drive rotor, and the friction drive torque generated through this sliding contact allows the button to move using the driving force of the drive rotor even when the clutch is engaged. It has been considered to rotate the cam body to release the slight engagement and measure the smoothness of the clutch engagement operation. When the waveform cam of the rotating body is in a slight occlusion state near the ridge located on the lower side in the rotational direction, the movable cam body receives more force than the reverse torque (load torque) applied to the movable cam body by pressing the button on this slight occlusion. Given.

The frictional drive torque from the drive rotary body may be smaller, and there is a risk that the desired objective may not be achieved.

And, as an incentive to exacerbate this problem, usually
Lubricating oil is stored in the transmission case in which this type of clutch is housed, and this lubricating oil reduces the generation of drive torque through the aforementioned friction.

The present invention aims to solve the above-mentioned problem, and when the above-mentioned clutch is buttoned and the waveform cam is in a slight engagement state, a reverse torque for driving the driven rotating body is generated in this slight engagement part. A friction drive portion is formed between the movable cam body and the drive rotation body so that the friction drive torque generated at the sliding contact portion between the movable cam body and the drive rotation body becomes uniform. .

In other words, even if the wave-shaped cam is in a slight engagement state when the clutch is engaged, the movable cam body tends to be rotated together with the driving rotary body, and the driven rotary body is stopped due to its own inertia and load. As a result, the movable cam body rotates relative to the fixed driven rotary body, causing a slight occlusal state force; The troughs of the other wavy cam are located at positions corresponding to the peaks of the other wavy cam, and in this state both wavy cams are brought into engagement with each other by the biasing force.

First, in the present invention, by reliably rotating the driven rotating body and the movable cam body relative to each other when the clutch is engaged, it is possible to solve the above-mentioned problem and perform a smooth latch engagement operation.

Embodiments of the present invention will be described in detail below based on illustrative drawings.

The figure shows a steering clutch installed in the transmission case of a power tiller. A driving rotary body 3 to which is transmitted is pivotally supported.

The upper portions of the axles 1 and 2 are biased toward the driving rotary body 3 by springs 4as4b, and have protrusions 5a and 5b protruding toward the driving rotary body 3 through communication holes formed in the driving rotary body 3. The driven rotors 7 and 8 are configured to constantly engage with the
It is spline-connected so as to be slidably displaceable in the axis X direction, and is configured to be in a clutch engaged state when the driven rotary bodies 7 and 8 and the driving rotary body 3 are engaged relative to each other, and this clutch engaged state The system is configured as described below to forcefully turn off the power.

Note that the left and right axle 1 and 2 side portions are constructed in the same manner, and the right axle 1 portion showing the clutch disengaged state will be described below.

That is, between the driving rotary body 3 and the driven rotary body 7, the shaft is in sliding contact with the side surface of the driving rotary body 3 and is regulated to a constant position in the axis X direction with respect to the driving rotary body 3; A ring-shaped movable cam body 9 is provided so as to be rotatable around the center X, and a wave-shaped cam 10a formed on the driven rotary body 7 and a movable cam are provided at the opposing portion of the movable cam body 9 and the driven rotary body 7. A cam mechanism 10 is comprised of a wave-shaped cam 10b formed on the body 9.

As shown in FIG. 2, the movable cam body 9 is disposed opposite to the locking hole 11 formed on the outer periphery of the locking tool 12.
Due to the rocking engagement, rotation about the axis X is prevented, and the driven rotary body 1 is rotated relative to the driven rotary body 7, thereby removing the driven rotary body 1 from the drive rotary body 3 via the cam mechanism 10. The clutch is configured to be in a disengaged state by being relatively separated against the mating force.

The locking device 12 is provided in a continuous state with the transmission case, and is manually operated by gripping a grip lever provided near the control handle of the tiller.

Further, the tip of this locking tool 12 engages with a stepped portion 13 formed on the outer periphery of the driven rotary body 7 that is relatively spaced apart, thereby regulating the position of the driven rotary body T that is pressed to the clutch disengaged state. It is configured as follows.

Furthermore, when the locking tool 12 and the locking hole 11 are engaged with each other as shown in FIG. S2 is the tangent to the outer peripheral surface of the movable cam body 9 X1. It is formed in the direction perpendicular to X2, and is set so that the locking tool 12 is not subjected to the abutment suppressing action in the extraction direction even when the movable cam body 9 rotates.

Further, one end surface of the movable cam body 9 is configured to be in sliding contact with the side surface of the drive rotary body 3, and oil-removing notches 14' are provided at a plurality of locations in the circumferential direction around the rotation axis X. When the driving rotary body 3 and the movable cam body 9 rotate relative to each other, the protrusions 14 and the driving rotary body 3 are formed through the notches 14'. It is configured to remove lubricating oil present in the sliding contact area of the

As described above, when the lubricating oil is removed, the frictional drive torque generated at the sliding contact portion via the button projections 14 causes a force near the peaks of the waveform cams 10a, 10b and near the peaks. The friction drive unit 15 is set to be larger than the reverse torque for driving the driven rotary body I generated in the micro-occlusal state when the micro-occlusal state occurs (see Fig. 4).
is configured.

(Refer to FIG. 3) Note that the reverse torque for driving the driven rotating body generated in the minute engagement portion refers to the front surface of the waveform cam 10b located on the upper side in the rotational direction of the movable cam body 9, and the waveform cam 1.
This occurs when the rear surface of 0a is in a state of slight occlusion, and the friction torque is set to be more dog-friendly than this reverse torque.

According to the above configuration, in the steering clutch, the protrusions 5a and 5b are normally engaged with the communication hole 6 of the drive rotor 3, and the rotational force of the drive rotor 3 is transmitted to the axles 1 and 2.

As shown in the figure, in order to disengage the clutch to cut off power transmission to the axle 1, the locking tool 12 is swung to engage the locking hole 11 and the movable cam body 9 is rotated. make it incapacitated.

Then, the movable cam body 9 whose rotation is prevented and the driven rotary body I which is in the clutched state rotate relative to each other, and the waveform cams 10a and 1
0b, the driven rotating body T is displaced in a direction away from the movable cam body 9, and the protrusion 5a is forcibly separated from the communication hole 6, resulting in a clutch disengaged state.

Further, in order to put the clutch in the engaged state, if the locking action of the locking tool 12 is released, the driven rotary body 7 is moved toward the drive rotary body 3 side by the biasing force of the spring 4a, and the clutch is brought into the engaged state.

At this time, when the waveform cams 10a and 10b are brought into a state of slight occlusion, in which the areas near the peaks engage with each other, the first drive rotating body 3 and the movable cam body 9 rotate relative to each other, and the friction drive unit 15 The movable cam body 9 rotates together with the driving rotary body 3 and the driven rotary body 7 tries to maintain the fixed state, and the movable cam body 9 rotates relative to the driven rotary body 7, and the micro-biting state is released and the waveform cam 1
0a and 10b are in the required occlusal state.

As shown in Fig. 5, a steel ball 16 is rotatably attached to the tip of the crest of the wave-shaped cam 10b, so that the reverse torque for driving the driven rotating body that occurs in minute occlusions is reduced. may be configured.

[Brief explanation of the drawing]

The drawings illustrate embodiments of the clutch according to the present invention; FIG. 1 is a longitudinal sectional view showing the steering clutch in the transmission case, FIG. 2 is a sectional view taken along the line ■-■ shown in FIG. FIG. 3 is a partial plan view of the friction drive unit, FIG. 4 is a plan view showing a micro-occlusion state of the wave-shaped cam, and FIG. 5 is a plan view of another embodiment. 3... Drive rotating body, 7... Driven rotating body, 9... Movable cam body, 10a, 10b...
...Wave cam, 12...Locking tool, 15...
...Friction drive unit.

Claims (1)

[Claims] 1. The driving rotary body 3 and the driven rotary body 7 are provided so that they can be freely engaged and disengaged by relative movement in the direction of the rotation axis X, and are biased in the direction of engagement. A ring-shaped movable cam body 9 that is rotatable around the axis X is interposed, and a locking tool 12 that can be manually operated for fixing the rotation of the movable cam body 9 around the axis X is provided. Waveform cams 10b and 10a are provided at the fixed part of the device, and at the opposing part of the movable cam body 9 and the driven rotary body 7, and the movable cam body 9
By relatively rotating the driven rotating body 7,
The wave-shaped cams 10a, 1
．． When Ob is in a slight occlusion state, the friction drive torque generated at the sliding contact between the movable cam body 9 and the driving rotor 3 is greater than the reverse torque for driving the driven rotor generated at this minute occlusion. A clutch characterized in that a friction drive section 15 is formed between the movable cam body 9 and the drive rotary body 3 so that the clutch has the following characteristics.