JP2001330053A - Power transmitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmitting device capable of restricting the gear noise and a shock to be generated when switching the power transmission from OFF to ON. SOLUTION: This power transmitting device is formed of a driving rotor 11, a driven rotor 12 arranged opposite to the driving rotor 11, and a power outputting part 9 engaged with the driven rotor 12, and provided with a driven projection part 11b provided in the driving rotor 11, a driving projection part 12b provided in the driven rotor 12 so as to be engaged with the driving projection part 11b, and an elastic holding member 25 for elastically holding the driving projection part 11b and the driven projection part 12b in the condition that both the projection parts are separated at the predetermined angle θ of turn in the circumferential direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a power transmission device.

[0002]

2. Description of the Related Art As a power transmission device, a power take-out portion (a dog clutch, etc.) is disengaged from a side of a drive rotary body (an output gear, etc.) of a transmission which is rotationally driven by an engine. 2. Description of the Related Art There is known an apparatus in which rotation of an output gear (such as an output gear) is turned on / off to an output shaft (such as a PTO shaft) via a power take-out unit (such as a dog clutch).

[0003]

However, in such a type, a stationary power take-out portion (dog clutch, etc.) is disengaged from a side portion of a rotationally driven driving rotary body (output gear, etc.). Therefore, at the time of the engagement, that is, when the power transmission is switched from off to on, gear noise is likely to occur based on the relative rotation difference between the two. Further, since a large shock is generated at the time of engagement, the shift feeling deteriorates, and a large impact is applied to the control system (shift rod, shift fork, etc.).

[0004] These problems are caused by the fact that the driver disengages the clutch of the vehicle and waits for the rotation of the driving rotator (output gear or the like) of the transmission to sufficiently decrease before engaging the power take-out portion (dog clutch or the like). Although it does not occur if
The driver does not always take such usage.
That is, when the driver erroneously rotates the driving rotating body (the output gear or the like) at a certain speed or more,
It is conceivable that the power take-out portion (dog clutch or the like) may be engaged, and in this case, various problems such as the above-described gear noise occur.

SUMMARY OF THE INVENTION An object of the present invention, which has been made in view of the above circumstances, is to provide a power transmission device capable of suppressing gear noise, shock, and the like that occur when power transmission is switched from off to on.

[0006]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a driving rotator, a driven rotator opposed to the driving rotator, and a power take-out portion which is disengaged from the driven rotator. A driving projection provided on the driving rotating body, a driven projection provided on the driven rotating body to be engaged with the driving rotating body, and a driving projection provided on the driven rotating body. And an elastic holding member that elastically holds the driven convex portion and the driven convex portion at a predetermined rotation angle in the circumferential direction.

According to the present invention, the driven rotary member rotates via the elastic holding member with the rotation of the driving rotary member. Power take-out part (stationary state)
Is engaged, the rotation of the driven rotor is stopped at that moment. At this time, the driven rotating body that had been rotating
When the power take-out portion is engaged, the gear rattles (tooth) because the elastic member is elastically connected to the driving rotary member and is rotated by the elastic holding member, and does not substantially transmit the rotational torque of the driving rotary member. Ringing) does not occur.

[0008] In contrast to the driven rotator to which the power take-out portion has been engaged and stopped, the driving rotator has a predetermined rotation angle until the driving projection engages with the driven projection of the driven rotator. When the elastic holding member is deformed, it relatively rotates.
During this relative rotation, the rotation of the driving rotator is not transmitted to the power take-out unit. Accordingly, if the engagement of the power take-out portion with the stationary driven rotating body is completed during that time, they can be smoothly engaged. Therefore, the shift feeling is improved, and the impact applied to the control system (such as the shift rod) is reduced.

After that, the relative rotation between the driving rotator and the driven rotator proceeds, and when the driving projection engages with the driven ridge, the driving rotator and the driven rotator rotate integrally again, and the driving rotator is rotated. Is transmitted to the power take-out unit. Thereby, the transmission of power is turned on. Then, when the power take-out part is separated from the driven rotor, the power transmission is turned off, and the driven rotor is
The elastic holding member returns to the original position (the position where the driving projection and the driven projection are separated by a predetermined rotation angle in the circumferential direction).

[0010] The elastic holding member may be configured to elastically hold the driven convex portion by positioning the driven convex portion behind the driving convex portion in the rotation direction. With this configuration, the predetermined rotation angle that separates the driving projection and the driven projection in the circumferential direction, that is, the predetermined rotation angle of the driving rotating body that rotates relatively to the driven rotating body is maximized. When the power take-out portion is engaged with the driven rotary body, the stationary time (time available for engagement) of both can be maximized.

Further, the elastic holding member may comprise a spring provided between the driving side rotating body and the driven side rotating body. Further, the power take-out section may have a dog clutch for the driven rotating body.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is an explanatory view of assembling each part of the power transmission device according to the present embodiment, FIG. 2 is a side sectional view of the power transmission device, and FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 3A is a diagram before power transmission, and FIG. 3B is a diagram after power transmission.

As shown in FIG. 2, this power transmission device 1
Has an output shaft 3 (PTO shaft) supported by the frame 2. The frame 2 includes a pair of support plate portions 4 and 4 arranged in parallel at a predetermined interval, and connection portions 5 and 5 connecting the support plate portions 4 and 4. The PTO shaft 3 is supported by the support plates 4, 4 via bearings 6, 6. A hole 8 through which the shift rod 7 is inserted is formed in each of the support plates 4. The shift rod 7 has a shift fork 10 that slides in the axial direction and engages with a shift sleeve 9 (power take-out part) described later.

The PTO shaft 3 has small-diameter portions 3a and 3a on which bearings 6 and 6 are mounted, a medium-diameter portion 3b on which an output gear 11 (drive rotator) and a driven rotator 12 are rotatably mounted, and The shift sleeve 9 (power take-out portion) is integrally formed with the large-diameter portion 3c which is rotatably fixed and axially movably mounted. The output gear 11 is mounted on the middle diameter portion 3b via a bearing 14 (a sliding bearing, a needle bearing, or the like). Output gear 11
Is meshed with a transmission gear (not shown), and is driven to rotate in the direction of arrow A by the engine.

The output gear 11 has a hole through which the PTO shaft 3 is inserted, as shown in FIG.
A disk-shaped gear body 11a formed with
cylindrical insertion portion 11c integrally formed on the side surface 16a of FIG.
And a drive projection 11b formed integrally with the outer peripheral surface 17 of the insertion portion 11c and the side surface 16 of the gear body 11a. As shown in FIG. 3, the driving protrusion 11 b is formed of a fan-shaped column having an opening angle of about 45 degrees when viewed from the axial direction, and its side surfaces 18 and 19 are located on the radiation from the center of the PTO shaft 3. It is molded as follows.

The medium diameter portion 3b of the PTO shaft 3 has a structure shown in FIG.
As shown in FIG. 2, the driven rotating body 12 is mounted via a bearing 20 (a sliding bearing, a needle bearing, or the like) so as to face the output gear 11.
The driven rotator 12 is integrally formed of a thick cylindrical portion 12a through which the PTO shaft 3 is inserted, and a driven convex portion 12b integrally formed on a side surface 21 (a surface facing the output gear 11) of the cylindrical portion 12a. Is molded. The driven convex portion 12b is formed of a fan-shaped column like the driving convex portion 11b, and has a side surface 2 of the cylindrical portion.
1 extends to the output gear 11 side.

As shown in FIG. 3, the driven convex portion 12b
It has a fan-shaped cross section with an opening angle of about 45 degrees when viewed from the axial direction, and is formed so that its side surfaces 22 and 23 are located on the radiation from the center of the PTO shaft 3. Driven convex portion 12b
Is such that its axial length is slightly longer than the axial length of the drive projection 11b, and the radius of its outer peripheral surface is
And the radius of the inner peripheral surface is formed to be slightly larger than the radius of the outer peripheral surface of the insertion portion 11c of the output gear 11. The side surfaces 22 and 23 of the driven convex portion 12b are disengaged from the side surfaces 18 and 19 of the driving convex portion 11b by the relative rotation of the output gear 11 and the driven rotary member 12, respectively.

As shown in FIGS. 1 and 2, a cylindrical cover 24 is fitted on the outer peripheral surface of the driven rotary member 12. The cover 24 is formed to have a length that accommodates the driving protrusion 11b and the driven protrusion 12b inside thereof. When the driving protrusion 11b and the driven protrusion 12b rotate relative to each other, there is something between them. (Such as a spring 25 to be described later) is prevented from intervening. The cover 24 is fixed to the outer peripheral surface of the cylindrical portion 12a of the driven rotating body 12 by press fitting, screwing, or the like. The cover 24 may be omitted.

As shown in FIG. 1, FIG. 2 and FIG. 3 (a), between the output gear 11 and the driven rotating body 12, a driving convex portion 11b and a driven convex portion As an elastic holding member that elastically holds in a state separated by the moving angle θ,
A helical spring 25 is interposed. The spring 25 has one end 25a linearly extended in the axial direction and is mounted in a hole 26 formed in the side surface 16 of the gear body 11a of the output gear 11, and the other end 25b linearly extends radially inward. The cylindrical portion 1 of the driven rotor 12 is extended and inserted through the hole of the cover 24.
It is mounted in a hole 27 formed in 2a.

As shown in FIG. 3 (a), the spring 25 moves the driven protrusion 12b in the normal state in the direction opposite to the rotation direction A of the drive protrusion 11b (the rotation direction of the output gear 11). And hold it elastically. That is, the spring 2
Reference numeral 5 denotes a relative rotation position between the output gear 11 and the driven rotary body 12 such that, in a normal state, the one side surface 23 of the driven convex portion 12b abuts on the rear surface 19 in the rotation direction of the driving convex portion 11b. As shown in FIG. 3B, when the output gear 11 rotates relative to the driven rotary body 12, as shown in FIG. Until the side surface 22 abuts, relative rotation between the two is allowed. The spring 25 has a return function of returning the state of FIG. 3B to the state of FIG.

Considering the return function of the spring 25, the winding direction of the spring 25 is determined when the output gear 11 rotates relative to the driven rotor 12 in the direction A shown by the arrow in FIG. It is set to tighten. However, the direction may be reversed. Further, the elastic holding member is not limited to such a helical spring 25, and may be a spring formed by gradually reducing the diameter of a leaf spring in a spiral shape. In short, the relative rotation between the output gear 11 and the driven rotary body 12 is changed from the state shown in FIG. 3A until the side face 18 in the rotation direction of the driving convex section 11b comes into contact with the other side face 22 of the driven convex section 12b. Acceptable,
In addition, any device having a function of returning the state of FIG. 3 (b) to the state of FIG. 3 (a) may be used.

As shown in FIGS. 1 and 2, a shift sleeve 9 as a power take-out portion is disengaged from the driven rotary member 12. On the inner peripheral surface of the shift sleeve 9, a groove 30 is formed which is engaged with a spline 29 formed on the large diameter portion 3c of the PTO shaft 3. The shift sleeve 9 is moved in the axial direction by the shift rod 7 via the shift fork 10 described above, and is engaged with and disengaged from the spline 31 formed in the cylindrical portion 12s of the driven rotating body 12. That is, the shift sleeve 9 functions as a dog clutch for the driven rotor 12. The splines 29 and 31 have the same shape.

The operation of the present embodiment having the above configuration will be described.

The output gear 11 is meshed with a gear of a transmission that is rotationally driven by the engine, so that the output gear 11 is rotationally driven if a vehicle clutch interposed between the engine and the transmission is connected. At this time, if the shift sleeve 9 is located only on the spline 29 of the PTO shaft 3 as shown in FIG.
As shown in FIG. 3A, the output gear 11 rotates on the PTO shaft 3 by pulling the driven rotor 12b backward in the rotational direction via a spring 25. In this state, the rotation of the output gear 11 is not transmitted to the PTO shaft 3 (power transmission off state).

The rotation of the output gear 11 is
The shift sleeve 9 (which is often stationary) shown in FIG. 2 is moved to the left via the shift fork 10 and the shift rod 7 so that the spline 29 of the PTO shaft 3 and the driven rotor 12 Straddling the spline 31. Thus, the PTO shaft 3 and the driven rotor 1
When the dog clutch is turned on, the rotation of the driven rotary body 12 that has been rotated by the output gear 11 via the spring 25 until then is stopped by the shift sleeve 9.

At this time, the driven rotating body 12 which has been rotating up to that time is elastically connected to the output gear 11 by the spring 25 and is being rotated, and substantially reduces the rotational torque of the output gear 11. Since the transmission is not transmitted, when the tip of the shift sleeve 9 is engaged with the spline 31 of the driven rotating body 12 and the rotation thereof is stopped, the shift sleeve 9 can be engaged with the spline 31 with a light shift force, and the gear noise is generated. (Toothing) does not occur.

That is, at the moment when the tip end of the shift sleeve 9 is engaged with the spline 31 of the driven rotor 12 (at the moment when the dog clutch is turned on), the rotational torque of the output gear 11 is substantially transmitted to the driven rotor 12. Since there is no gear noise (gear noise), it is possible to quickly engage without gear noise. Therefore, the shift shock is small, the shift feeling is improved, and the shock input to the control system (the shift rod 7, the shift fork 10, etc.) is reduced.

Then, as shown in FIG. 3 (b), the output gear 11 is driven by the driving projection 1 against the driven rotating body 12 stopped by the engagement of the tip of the shift sleeve 9.
The spring 25 is relatively rotated by being deformed (tightened) by a predetermined rotation angle θ until 1b engages with the driven protrusion 12b of the driven rotating body 12. During this relative rotation (from FIG. 3A to FIG. 3B), the rotation of the output gear 11 is not transmitted to the shift sleeve 9, that is, the PTO shaft 3.

As described above, while the output gear 11 rotates relative to the driven rotor 12 by the predetermined rotation angle θ shown in FIG. 3B, the spline 31 of the stationary driven rotor 12 is stationary. When the shift sleeve 9 is engaged to the back, that is, when the shift is completed, the driven rotor 12 and the shift sleeve 9 are both stationary during the shift, so that they are smoothly engaged. it can. Therefore, the force required for shifting is small, and no excessive force is applied to the shift fork 10 and the shift rod 7. Therefore, the shift feeling is improved.

Thereafter, the relative rotation of the output gear 11 with respect to the driven rotary member 12 proceeds, and the side surface 18 of the driving convex portion 11b of the output gear 11 comes into contact with the side surface 22 of the driven convex portion 12b of the driven rotary member 12. Then (the state shown in FIG. 3B), the driven rotating body 12 is pushed by the output gear 11 via the driven convex part 12b and the driving convex part 11b, and rotates together with the output gear 11 again. . As a result, the rotation of the output gear 11 is transmitted to the shift sleeve 9, that is, the PTO shaft 3 (power-on state).
At this time, the spring 25 is deformed so as to be tightened.

Thereafter, the shift sleeve 9 is pulled out of the spline 31 of the driven rotor 12 from the state shown in FIG.
(When the dog clutch is turned off), the transmission of rotation from the output gear 11 to the PTO shaft 3 is cut off,
The power is turned off. At this time, the driven rotating body 12 causes the restoring force of the spring 25, which has been tightened, to loosen.
The state shown in FIG. 3B is returned to the state shown in FIG.

Specifically, in the present embodiment, as shown in FIG. 3B, the predetermined rotation angle θ is approximately 270 ° (about 3/4 rotation).
And the rotation speed of the output gear 11 is 600 to 1000 rp.
m. Therefore, the time per rotation of the output gear 11 is 60 sec / (600 to 1000 rev) = 0.100
~ 0.060 sec / rev. Therefore, the time required for shifting from the state of FIG. 3A to the state of FIG. 3B, that is, the time available for shifting is 0.100 to 0.060 sec × 270 ° / 360 ° =
0.075 to 0.045 sec = 75 to 45 msec.

On the other hand, it has been experimentally confirmed that the time required for the shift (the time from when the tip of the shift sleeve 9 starts to mesh with the spline 31 to when the meshing of the shift sleeve 9 is completed) is about 10 msec. The time available for the shift
Shorter than 75msec-45msec. For this reason, at the time of shifting, the driven rotating body 12 is always stopped during the time required for shifting, and the shift sleeve 9 (stopped state) does not cause excessive force on the shift fork 10 and the shift rod 7, and the shift sleeve 9 (stopped state) causes the power to be turned off. A smooth shift to ON can be secured.

Further, in this embodiment, as shown in FIG. 3A, the spring 25 positions the driven convex portion 12b in the direction opposite to the rotation direction A of the driving convex portion 11b so as to elastically hold the driven convex portion 12b. Since they are set, the driving projection 11b and the driven projection 12b
A predetermined rotation angle θ that separates the output gear 11 in the circumferential direction, that is, the output gear 11 that can relatively rotate with respect to the driven rotor 12.
Is the maximum (approximately 270 °). Therefore, when the shift sleeve 9 is engaged with the spline 31 of the driven rotating body 12, the stationary time (time available for shifting) of both can be maximized.

The spring 25 may be set so as to elastically hold the driven projection 12b and the driving projection 11b at an interval of about 180 °. That is, the predetermined rotation angle is set to approximately 180
° may be used. In this case, even when the rotation direction of the output gear 11 is the opposite direction, the same operation and effect as described above can be obtained. Even in this case, the time available for the shift is (75 msec to 45 msec) / 2
= 37.5msec ~ 22.5msec, shift time 10ms
Longer than ec, no problem.

When the state shown in FIG. 3A is shifted to the state shown in FIG. 3B, the side surface 18 of the driving projection 11b collides with the side surface 22 of the driven projection 12b. Alternatively, a buffer material such as urethane rubber may be attached to 22 by bonding, welding, screwing, or the like to prevent metal noise at the time of collision. Similarly, when the reset state is changed from the state of FIG. 3B to the state of FIG. 3A, the side surface 19 of the driving convex portion 11b collides with the side surface 23 of the driven convex portion 12b. A cushioning material such as urethane rubber may be attached to the side surface 19 or 23.

The shift sleeve 9 is connected to the driven rotor 12
(When the dog clutch is on), the shift sleeve 9, that is, the PTO shaft 3 does not necessarily need to be stationary, and may be rotating.
However, the rotational speed (r
pm) must be lower than the rotation speed (rpm) of the output gear 11. If the speed is fast, the passive convex portion 12b presses the driving convex portion 11b in the arrow direction A in FIG. 3A, and the state does not shift to the state of FIG. 3B.

In FIG. 2, on the left side of the PTO shaft 3 (small diameter portion 3a), a power transmission device 1 similar to the right side described above is provided.
May be modified and attached in the direction of rotation. In this way, when the rotation direction of the output gear 11 is the direction indicated by the arrow A in FIGS. 1 to 3, power can be taken out from the power transmission device 1 described above shown in FIG. When the rotation direction of is opposite to the arrow A,
In FIG. 2, power can be taken out from a power transmission device which is attached to the left side of the PTO shaft 3 (small diameter portion 3a) and is modified in a rotational direction.

FIG. 4 shows another embodiment. As shown in the figure, the power transmission device 1a according to this embodiment has the same basic configuration as that of the previous embodiment. Therefore, parts that perform the same functions are denoted by the same reference numerals as those of the previous embodiment. Description is omitted. In this embodiment, the driven convex portion 12b is attached to the outer peripheral surface of the driven rotary member 12, the insertion portion 11c of the output gear 11 of the previous embodiment is omitted, and the driven convex portion 12b is the same as the previous embodiment. Drive projection 11
Since the engagement is made not from the front in the axial direction of b but from the inside in the radial direction, the overall length of the device can be shortened.

[0041]

As described above, according to the power transmission device of the present invention, it is possible to suppress gear noise, shock, and the like that occur when power transmission is switched from off to on.

[Brief description of the drawings]

FIG. 1 is an explanatory view for assembling components of a power transmission device according to an embodiment of the present invention.

FIG. 2 is a side sectional view of the power transmission device.

3 is a cross-sectional view taken along the line III-III of FIG. 2, wherein FIG. 3 (a) is a diagram before power transmission and FIG. 3 (b) is a diagram after power transmission, respectively.

FIG. 4 is an explanatory view for assembling components of a power transmission device according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power transmission device 9 Shift sleeve as power take-out part 11 Output gear as drive rotating body 11b Drive convex part 12 Driven rotary body 12b Drive convex part 25 Spring as elastic holding member θ Predetermined rotation angle

Claims (4)

[Claims] 1. A power transmission device comprising: a driving rotator; a driven rotator disposed to face the driving rotator; and a power take-out portion engaged and disengaged from the driven rotator. A driving projection provided on the body, a driven projection provided on the driven rotating body to be engaged with the driving projection, and a predetermined rotation angle separation between the driving projection and the driven projection in the circumferential direction. And a resilient holding member for resiliently holding the power transmission device. 2. The elastic holding member according to claim 1, wherein:
The power transmission device according to claim 1, wherein the power transmission device is positioned adjacent to a rear side of the driving protrusion in the rotation direction and elastically held. 3. The power transmission device according to claim 1, wherein the elastic holding member comprises a spring provided between the driving side rotating body and the driven side rotating body. 4. The power transmission device according to claim 1, wherein the power take-out portion has a dog clutch for the driven rotating body.