JP2000110896A - Power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily provide a jamming resisting function through a simple design. SOLUTION: A pair of differential gear mechanisms 5 and 6 having the same gear trains 5A and 6A (5B, 6B) are intercoupled through two systems of power transmission systems A and B. A rotation power inputted to a shaft 3 is divided once and thereafter, the division powers are united together and outputted to an output rotary body 4. Thereby, even when jamming occurs to either of the power transmission systems A and B, proper power transmission is effectively continued. Besides, regulation between rotation powers outputted to the output rotary body 4 during ordinary operation and during jamming is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission device which has an effective anti-jamming function and can be designed easily.

[0002]

2. Description of the Related Art As an actuator for a flight control system of an aircraft, a mechanical actuator that can be designed compactly is promising. In general, this type of actuator is configured so that the power of the motor is taken out to the output side via a speed reducer and the steering angle can be changed by the output. However, jamming occurs on the transmission path of the actuator. If this occurs, the steering angle cannot be changed, which directly leads to a fatal accident of the aircraft.

In view of such a problem, conventionally, in order to prevent jamming, a configuration is adopted in which rotational power can be transmitted to an output end in two systems, and operation can be continued in another system even if a part of the system is jammed. That is what is being considered.

[0004]

Incidentally, as a countermeasure to be taken in the past, a so-called clutch system or a shear section system in which a transmission system path is mechanically cut off, or a power system divided by a differential gear mechanism is used. In general, any one of a so-called planetary gear system and a differential gear system in which the two are taken out to the output side in parallel, respectively, is employed.

However, in the former case, it is difficult to set the release torque. In the latter case, there is a disadvantage that the output (speed or driving force) changes during jamming as compared with the normal operation, and even if an attempt is made to resolve this, the change is eliminated only under a limited specific gear ratio. I could not do it. The present invention has been made in view of such a problem, and an object of the present invention is to provide a power transmission device which has an effective anti-jamming function and can be easily designed.

Further, the present invention suitably utilizes the principle of the power transmission device having such a configuration, and provides a function of positively generating a jamming state. It is another object of the present invention to enable the gear ratio between the two to be efficiently switched.

[0007]

In order to achieve the above object, the present invention takes the following measures.
That is, the power transmission device of the present invention provides the first and second differential gear mechanisms in which the rotational power input to the input end is arranged in the first stage.
Of the differential gear mechanism in which the rotational power transmitted to the first and second power transmission systems is arranged at the final stage after that. First,
The gear train of the first-stage differential gear mechanism and the gear train of the last-stage differential gear mechanism are integrated with each other via the second gear train and taken out to the output end. It is characterized by the same or similar gear train.

[0008] With this configuration, regardless of which of the first and second power transmission systems is jammed, the power transmission system is fixed and the other power transmission system is operated effectively. Thus, power transmission between the input terminal and the output terminal can be continuously performed. Therefore, the gears may remain meshed, and setting of release torque and the like become unnecessary.
Moreover, the power distributed through each gear train of the first stage differential gear mechanism is integrated by passing through the same or similar gear train of the differential gear mechanism arranged at the last stage, so that during normal operation In addition to making it easier to adjust the rotational power taken out to the output end during jamming and jamming, when a speed reducer or the like is interposed in each power transmission system, the setting of the reduction ratio etc. This can be performed without being greatly influenced by the existence of the dynamic gear mechanism.

In particular, transmission ratios different from each other are set by interposing a speed reducer or the like in a part of the first and second power transmission systems, and one of the power transmission systems is selectively locked by a brake mechanism. In such a case, jamming can be positively generated in one of the power transmission systems, and the rotation speed of the output end can be efficiently switched while operating.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. <First Embodiment> A power transmission device of this embodiment is used by being incorporated into a wing or the like as an actuator for a flight control system of an aircraft, and is divided into right and left at the center as shown in FIGS. A shaft 3 is supported by a housing 1 via a bearing 2, an output rotating body 4 is disposed at a divided portion of the housing 1, and a pair of planetary gear mechanisms 5 and 6 as a differential gear mechanism in the housing 1. The first and second power transmission systems A and B having reduction gears 7 and 8, respectively, are housed therein, and the rotational power input to the shaft 3, which is the input end, is located at the first stage. First and second gear trains 5A and 5B of the planetary gear mechanism 5 respectively
After splitting into the second power transmission systems A and B, the rotation power transmitted to the first and second power transmission systems A and B is then divided into the first and second rotations of the planetary gear mechanism 6 located at the final stage. 2 gear train 6
A and 6B are integrated and taken out from the output rotating body 4 which is an output terminal.

More specifically, the first stage planetary gear mechanism 5 includes a sun gear 51 disposed on the outer periphery of the shaft 3 and a planetary gear 52 supported by a gear retainer 50 fixed to the shaft 3 so as to be integrally rotatable. A ring gear 5 disposed between the planetary gear 52 and the housing 1
3 are engaged with each other. The final stage planetary gear mechanism 6 includes a gear retainer 6 on the output rotary body 4.
0, and a sun gear 6 disposed between the planetary gear 62 and the shaft 3.
1 and a ring gear 63 that is freely rotatable around the planetary gear 62.

On the other hand, the first power transmission system A is mainly composed of a speed reducer 7 called a compound, and the speed reducers 7 are connected to each other via a support shaft 70. An external gear 7 mainly comprising a pair of spur gears 71 and 72, one of which is disposed on the outer periphery of the shaft 3.
3 and an internal gear 74 formed on the inner periphery of the housing 1 simultaneously to form a planetary gear mechanism.
2 is meshed with an internal gear 75 disposed on the outer periphery thereof. The external gear 73 of the speed reducer 7 and the ring gear 53 of the first stage planetary gear mechanism 5 are integrally rotatably connected via a cup-shaped first connecting member 91, and the internal gear 75 And the ring gear 63 of the planetary gear mechanism 6 at the last stage are connected so as to be integrally rotatable via a cylindrical second connecting member 92, and the first and second connecting members 91, including the speed reducer 7, The first power transmission system A is provided between the portions 92.

The second power transmission system B is mainly composed of a speed reducer 8 also called a compound. The speed reducer 8 is also composed of a pair of mutually connected via a support shaft 80. An external gear 83 mainly composed of spur gears 81 and 82 and one spur gear 81 disposed on the outer periphery of the shaft 3
And an internal gear 84 formed on the inner periphery of the housing 1 to form a planetary gear mechanism.
Is meshed with an internal gear 85 disposed on the outer periphery thereof. The external gear 83 of the speed reducer 8 and the sun gear 51 of the first stage planetary gear mechanism 5 are integrally rotated via a third cylindrical connecting member 93 which is freely rotatably mounted on the outer periphery of the shaft 3. And the internal gear 8
5 and the sun gear 61 of the planetary gear mechanism 6 at the final stage are integrally rotatably connected via a cup-shaped fourth connecting member 94, and the third and fourth connecting members 93, including the speed reducer 8,
A portion between 94 is a second power transmission system B.

That is, in this power transmission device, the rotational power input to the shaft 3 as the input end is transmitted via the planetary gear 52 → the ring gear 53 which is the first gear train 5A of the planetary gear mechanism 5 in which the rotational power is arranged at the first stage. 1 power transmission system A
And the planetary gear 52 which is the second gear train 5B →
The planetary gear mechanism 6 is divided into the second power transmission system B via the sun gear 51, and then the rotational power transmitted to the first power transmission system A is reduced by the speed reducer 7 and arranged at the final stage. The ring gear 63 which is the first gear train 6A → the output rotating body 4 which is the output end via the planetary gear 62,
After the rotational power transmitted to the second power transmission system B is reduced by the speed reducer 8, the second gear train 6 of the planetary gear mechanism 6
The sun gear 61 which is B → the planetary gear 62 is integrated and taken out to the output rotary body 4. That is, the first gear train 5A of the first stage planetary gear mechanism 5
And the first gear train 6A of the last-stage planetary gear mechanism 6, and the second gear train 6B of the first-stage planetary gear mechanism 5 and the second gear train 6B of the last-stage planetary gear mechanism 6, respectively. The planetary gear train uses the same gear train.

In FIG. 3, reference numerals Za to Zg exemplify the number of teeth set for each gear, and those indicated by the same reference numerals among Za to Zg mean that the same number of teeth are set. are doing. Next, when rotational power having an angular velocity ω is input to the shaft 3 serving as the input end, how the angular velocity ω5 of the output rotating body 4 serves as the output end is calculated. Therefore, in the first stage planetary gear mechanism 5, it is assumed that the angular velocity of the ring gear 53, that is, the angular velocity ω1 of the first connecting member 91 is αω, the angular velocity ω2 of the second connecting member 92, the angular velocity ω3 of the third connecting member 93, Fourth connecting member 9
4 is obtained. Assuming that the reduction ratio of the reduction gears 7 and 8 is K, ω1 = αω (1) ω2 = K · ω1 = K · αω (2) ω3 = (1 + Zc / Za−α · Zc / Za) ω ( 3) ω4 = K · ω3 = K · (1 + Zc / Za−α · Zc / Za) ω (4) where K = {Zd · Zg / (Zf · Ze) −1} / {Zd · Zg / ( Zf · Ze) + Zd · Zg / (Za · Ze)｝ (5) On the other hand, since the angular velocity ω5 of the output rotating body 4 is ω5 = (ω4 + ω2 · Zc / Za) / (1 + Zc / Za) (6), the equations (2) and (4) are substituted into the equation (6). Then, ω5 = K · ω (7), and it can be seen that a constant rotational power is obtained in the output rotating body 4 regardless of α. That is, ideally ω1 =
Not only the state of ω3 (that is, the state of α = 1), but also ω1 and ω2 become 0 and the first power transmission system A jams (state of α = 0), and ω3 and ω4 become 0 and the 2 when the power transmission system B jams (ω3 = 0
= 1 + Za / Z obtained from equation (3)
In the state (c), the relationship shown by the equation (7) is always established.

The numerical values shown in parentheses in FIG. 3 are specific examples of the number of teeth of each gear. By substituting these values into equation (5), equation (7) gives ω5 = 0.009809ω, which indicates that a large reduction ratio can be obtained. In this manner, the power transmission device of the present embodiment uses the jammed power transmission system A (B) as a fixed point regardless of which of the first and second power transmission systems A and B is jammed. Of the power transmission system B (A) can be continuously operated effectively, and the power transmission between the shaft 3 as the input end and the output rotating body 4 as the output end can be continuously performed. Therefore, the gears of each part may be kept in mesh with each other, and setting of release torque and the like are not required at all. Moreover, the power distributed through the respective gear trains 5A and 5B of the first stage planetary gear mechanism 5 is transmitted to the gear trains 6A and 6B of the planetary gear mechanism 6 arranged at the last stage.
, It is easy to adjust the rotational power taken out to the output rotating body 4 during normal operation and jamming, and it is also possible to intervene in the power transmission systems A and B. It is possible to set the reduction ratio of the speed reducers 7 and 8 without depending on the existence of the two planetary gear mechanisms 5 and 6. In addition, structurally, a reducer called a planetary gear mechanism or a compound is adopted, and can be configured using only general element parts.
Since it can be built compactly in the wing together with the motor, it is extremely suitable for the reduction in size and weight required for aircraft.

In particular, in this embodiment, the first and last stage planetary gear mechanisms 5 and 6 have the same number of teeth (Za, Zb, Zc) and the output rotation described by symmetrically arranging them is α. Is not affected, the same output can be obtained in a wide range from normal operation to various jamming states, and the steering of the wing can be made stable and reliable. Moreover, in the present embodiment, the same reduction gears 7, 8 interposed in the power transmission systems A, B are adopted and arranged symmetrically, and the output rotation is equal to the number of teeth of the reduction gears 7, 8. Since it is determined only by the setting, the reduction ratio can be designed very easily.

The specific configuration of each part is not limited to the above-described embodiment. For example, the setting of the number of teeth between the planetary gear mechanisms 5 and 6 and the setting of the number of teeth between the reduction gears 7 and 8 do not necessarily have to be the same. Can be raised. Of course, when it is necessary to positively change the output rotation between normal operation and jamming, the setting of the number of teeth between the planetary gear mechanisms 5 and 6 and the setting of the number of teeth between the reduction gears 7 and 8 are not similar. You just have to shape it. Also in this case, since the gear train having the same structure is merely adjusted mechanically, it can be designed relatively easily. Further, instead of the planetary gear mechanism, a bevel gear mechanism may be arranged at the first stage and the last stage as the differential gear mechanism. Of course, even if a planetary gear mechanism is arranged at one of the first stage and the last stage, and a bevel gear mechanism is used at the other stage, these are similar mechanisms that behave in the same way, so that the same operational effects as above can be obtained. Can be. Further, in the above embodiment, the rotational power input to the planetary gear is taken out from the planetary gear, but a configuration in which the rotational power input to the sun gear is taken out from the sun gear and a configuration in which the rotational power inputted to the ring gear is taken out from the ring gear are adopted. Can also.

Other configurations can be variously modified without departing from the spirit of the present invention. <Second Embodiment> Next, by adopting a basic structure similar to that of the first embodiment and adding a mechanism capable of positively causing jamming, the shaft 3 serving as an input end is formed.
FIG. 4 shows an embodiment in which the reduction ratio between the output rotary body 4 and the output end can be switched while operating.

In this case, the shaft 3 as an input end is also used.
Planetary gear mechanism 5 in which the rotational power input to the first stage is located
Are divided into first and second power transmission systems A and B via first and second gear trains 5A and 5B, respectively, and then transmitted to the first and second power transmission systems A and B. The obtained rotational power is integrated via the first and second gear trains 6A and 6B of the planetary gear mechanism 6 located at the final stage, and is taken out from the output rotary body 4 which is the output end. This is the same as the first embodiment. The features of this embodiment are that the reduction ratios of the two power transmission systems A and B are set to different values, and that the two power transmission systems A and B are located at positions where they can be selectively locked. The point is that the brake mechanisms 100 and 200 are provided.

More specifically, when the speed reducers 7 and 8 are configured, the external gears 73 and 83 have different numbers of teeth Za.
1, Za2, and spur gears 71, 81 with different numbers of teeth Zd1,
Zd2 has spur gears 72, 82 with different numbers of teeth Ze1, Ze.
2, the internal gears 74 and 84 are different in the number of teeth Zf1 and Zf2.
In addition, the internal gears 75 and 85 are set to different numbers of teeth Zg1 and Zg2, respectively.

On the other hand, the brake mechanisms 100 and 200 may be located at any position where the power transmission systems A and B can be locked. As an example, the brake mechanism 100 is a drum type using expansion and contraction of a shoe. 1 connecting member 91
Or the brake mechanism 200 may be of a drum type utilizing the expansion and contraction of the shoe, and may be disposed at a position where the inner peripheral surface of the third connecting member 93 can be locked. Can be.

Next, the angular velocity ω is applied to the shaft 3 which is the input end.
Is calculated, the angular velocity ω5 of the output rotator 4, which is the output end, when the rotational power is input. Therefore, in the first stage planetary gear mechanism 5, the ring gear 5
3, that is, the angular velocity ω1 of the first connecting member 91 is α
Assuming that ω, the angular velocity ω2 of the second connecting member 92, the angular velocity ω3 of the third connecting member 93, and the angular velocity ω4 of the fourth connecting member 94 are obtained. The reduction ratio of the reduction gears 7, 8 is K1,
If K2, ω1 = αω (1) ω2 = K1 · ω1 = K1 · αω (2) ω3 = (1 + Zc / Za−α · Zc / Za) ω (3) ω4 = K2 · ω3 = K2・ (1 + Zc / Za−α · Zc / Za) ω (4) where K1 = {Zd1 · Zg1 / (Zf1 · Ze1) −1} / ｛Zd1 · Zg1 / (Zf1 · Ze1) + Zd1 · Zg1 / ( (Za1 / Ze1)} (5) K2 = {Zd2 / Zg2 / (Zf2 / Ze2) -1} / {Zd2 / Zg2 / (Zf2 / Ze2) + Zd2 / Zg2 / (Za2 / Ze2)} (5) ' It is.

On the other hand, when the brake 200 is applied, only the power transmission system A operates, and the angular velocity ω5 of the output rotary body 4 is (α = (1 + Zc / Za) / (Zc / Za)) ω5 (1) = (Ω2 · Zc / Za) / (1 + Zc / Za) (6), and when the brake 100 is applied, only the power transmission system B operates and (α = 1 + Zc / Za) ω5 (2) = ω4 / (1 + Zc / Za) (6) ', and when neither of the brakes 100 or 200 is applied, both power transmission systems A and B rotate together, and (α = 1) ω5 (3) = ( ω4 + ω2 · Zc / Za) / (1 + Zc / Za) (6) ″.

As described above, depending on which of the power transmission systems A and B actively jams, the output at the output end can be efficiently performed while operating as shown in the above equations (6) and (6) '. The rotation speed of the rotator 4 can be switched, and the rotation speed can be set to be free.
Since it can be switched as in the formula, the continuity and stability of operation can be improved as compared with a clutch type transmission mechanism etc., and because it is configured through constant gear engagement compared with a fluid clutch etc. Efficiency can be significantly improved.

In this embodiment, various modifications in accordance with the first embodiment can be made.

[0027]

As described above, according to the present invention, a pair of differential gear mechanisms having the same or similar gear train are connected via a two-system power transmission system, and the rotational power is once divided. After that, they are integrated and output. Therefore, appropriate power transmission can be effectively continued regardless of which power transmission system is jammed. In addition, there is no need to set release torque, etc., and it is easy to adjust the rotational power taken out at the output end during normal operation and during jamming. An excellent effect is achieved in that a configuration for generating a predetermined output change and a configuration for obtaining a desired reduction ratio can be easily realized with a high degree of design freedom.

Also, in the case where each power transmission system is set to a different transmission ratio by utilizing such a configuration in principle, any one of the power transmission systems can be selectively locked by a brake mechanism. Thus, it is possible to efficiently switch the rotation speed of the output end while operating.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a first embodiment of the present invention.

FIG. 2 is a schematic explanatory view of a mechanism corresponding to FIG. 1;

FIG. 3 is a schematic explanatory view of a mechanism corresponding to FIG. 1;

FIG. 4 is an explanatory view of a mechanism corresponding to FIG. 3 showing a second embodiment of the present invention.

[Explanation of symbols]

 A: first power transmission system B: second power transmission system 3: input end (shaft) 4: output end (output rotating body) 5: first stage differential gear mechanism (planetary gear mechanism) 5A: first Gear train 5B Second gear train 6 Final differential gear mechanism (planetary gear mechanism) 6A First gear train 6B Second gear train 100 Brake mechanism 200 Brake mechanism

Claims (2)

[Claims] 1. A rotary power input to an input terminal is divided into first and second power transmission systems via first and second gear trains of a differential gear mechanism arranged at a first stage, respectively. , Wherein the rotational power transmitted to the first and second power transmission systems is integrated via first and second gear trains of a differential gear mechanism arranged at the final stage, and is taken out to an output end. Wherein the gear train of the first stage differential gear mechanism and the gear train of the last stage differential gear mechanism are mechanically identical or similar to each other. 2. The power transmission system according to claim 1, wherein the first and second power transmission systems are set to have different transmission ratios, and a brake mechanism is provided for selectively locking either one of the power transmission systems. 1. The power transmission device according to 1.