JP6319063B2 - Driving force transmission device and control program therefor - Google Patents

Description

  The present invention relates to a driving force transmission device that intermittently transmits a driving force of an input shaft to an output shaft, and a control program therefor.

  2. Description of the Related Art Conventionally, a driving force transmission device that transmits driving of an input shaft to an output shaft by changing angular velocity or torque has been used. For example, Patent Document 1 discloses a continuously variable transmission as a driving force transmission device for a vehicle.

  The continuously variable transmission has an output shaft arranged in parallel with the input shaft. The input shaft is provided with six eccentric mechanisms that rotate eccentrically with the rotation of the input shaft. Each eccentric mechanism is arranged around the input shaft so as to change the phase of the center by 60 °. Further, the continuously variable transmission includes a swing link that swings and rotates in the pushing direction and the return direction when each eccentric mechanism rotates. Further, a clutch for engaging the swing link and the output shaft is provided.

  The continuously variable transmission intermittently transmits the drive of the input shaft to the output shaft. That is, when the eccentric mechanism rotates in accordance with the rotation of the input shaft, the swing link is swung in the push direction side. At this time, the clutch engages the swing link and the output shaft to rotate the output shaft. When the swing link swings and rotates in the return direction, the clutch is disengaged. In this manner, the swing links are sequentially engaged with the output shaft, and the output shaft is rotated by 60 ° each time the engagement is engaged.

JP 2012-251619 A

  By the way, in the conventional driving force transmission device, the timing at which one transmission means (for example, the eccentric mechanism, the swing link, and the clutch group) transmits the driving force to the output shaft is synchronized with the rotation of the input shaft. The timing is fixed. For example, the driving force is transmitted to the output shaft only once while the input shaft rotates once. For this reason, it becomes difficult to respond to flexible drive transmission such as a change in transmission timing. Therefore, an object of the present invention is to provide a driving force transmission device capable of transmitting a driving force asynchronously with rotation of an input shaft.

  The present invention relates to a driving force transmission device. The apparatus includes a first rotating shaft, a second rotating shaft that rotates in the opposite direction to the first rotating shaft, an elastic member, and a vibrator. One end of the elastic member is fixed to the second rotating shaft, the other end of the elastic member is fixed to the vibrator, and the vibrator is connected to the first rotating shaft; It is possible to be in any one of a second state in which the connection is released, a third state in which the connection is fixed to the fixing member, and a fourth state in which the fixation is released. When the elastic member can bias the second rotating shaft in a direction opposite to the rotating direction of the second rotating shaft, the vibrator is in the first state, and the first rotating shaft and the By the two rotation shafts, the elastic member further accumulates elastic energy for urging in the opposite direction. When the elastic member can bias the second rotation shaft in the rotation direction of the second rotation shaft, the vibrator enters the third state, and biases the second rotation shaft in the rotation direction. The elastic energy of the elastic member is released.

  According to the present invention, the driving force can be transmitted asynchronously with the rotation of the input shaft.

It is a schematic diagram of the driving force transmission device according to the present embodiment. It is a schematic diagram explaining operation | movement of the driving force transmission apparatus which concerns on this embodiment. It is a schematic diagram explaining operation | movement of the driving force transmission apparatus which concerns on this embodiment. It is a schematic diagram explaining operation | movement of the driving force transmission apparatus which concerns on this embodiment. It is a schematic diagram explaining operation | movement of the driving force transmission apparatus which concerns on this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a schematic diagram explaining the structure of the driving force transmission apparatus which concerns on this embodiment. It is side surface sectional drawing which illustrates the drive force transmission device which concerns on this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which illustrates the speed change result by the driving force transmission device concerning this embodiment. It is a figure which shows another example of the speed change result by the driving force transmission apparatus which concerns on this embodiment. It is a figure explaining the detail of FIG.

  In FIG. 1, the schematic diagram of the driving force transmission apparatus 10 which concerns on this embodiment is shown. The driving force transmission device 10 includes an input shaft 12, an output shaft 14, a transmission member 16, a control unit 19, and speed sensors 21A and 21B. The driving force transmission device 10 is used as a transmission means for transmitting driving force from a driving source such as an internal combustion engine of a vehicle to driving wheels, for example.

  The input shaft 12 is driven to rotate by a drive source (not shown). The output shaft 14 is provided so as to be separated from the input shaft 12 and is provided coaxially with the input shaft 12. The output shaft 14 may have a hollow shape, for example, as shown in FIG. 1, and the input shaft 12 may be disposed therein, or may be coaxial with the input shaft 12 as shown in FIG. It may be arranged side by side.

  The transmission member 16 transmits the driving force of the input shaft 12 to the output shaft 14 via the elastic member 18. As will be described later, the transmission member 16 transmits the driving force of the input shaft 12 to the output shaft 14 in synchronization with the vibrator 20 that reciprocates along the axial direction of the input shaft 12. In addition, in FIG. 1, although the two transmission members 16 are provided on the output shaft 14, it is not restricted to this form. For example, the number of transmission members 16 may be one. Further, in order to balance in the radial direction (as a counterweight), a plurality of transmission members 16 may be provided on the axial object. The transmission member 16 includes an elastic member 18, a vibrator 20, a clutch 22, and a brake 24.

  The elastic member 18 is provided with a fixed point on the output shaft 14, and extends around the axis circumference at a position off the axis of the output shaft 14. For example, a slot is formed in the axial end surface of the output shaft 14 along the circumferential direction, and the elastic member 18 is disposed in the slot. The slot serves as a guide, and the elastic member is expanded and contracted (elastically vibrated) along the circumference of the output shaft 14. The elastic member 18 may be composed of, for example, a coil spring, and one end along the length direction is fixed to the output shaft 14 and the other end is fixed to the vibrator 20.

  The vibration period of the elastic member 18 is preferably formed so as to be shorter than the maximum rotation period of the drive source. For example, when the drive source is an internal combustion engine and the maximum rotation speed (maximum allowable rotation speed) is 6000 rpm (= 100 Hz), it is preferable to include the elastic member 18 having a natural frequency higher than 100 Hz. In this way, as will be described later, it is possible to transmit the driving force to the output shaft 14 a plurality of times during one rotation of the input shaft 12.

  The vibrator 20 is connected to the elastic member 18 and is reciprocated along the axial circumferential direction of the output shaft 14 as the elastic member 18 expands and contracts. The vibrator 20 may be made of a rigid material such as metal, and may be formed of a weight that reciprocates along the slot together with the elastic member 18, and is coaxial with the output shaft 14 as shown in FIG. It may be a transmission shaft that is arranged and rotates around the axis as the elastic member 18 expands and contracts.

  The clutch 22 is an engaging means for engaging the vibrator 20 with the input shaft 12. The clutch 22 is configured to be able to engage / release the vibrator 20 and the input shaft 12 at high speed. For example, it is preferable that the engagement / release can be performed in a cycle shorter than the frequency of the elastic member 18. From this, the clutch 22 is comprised from the electromagnetic clutch which performs the operation | movement of engagement / release, for example by the interruption of the electric power to an electromagnet.

  The clutch 22 may be a one-way clutch. The one-way clutch is mechanically operated according to the relative speed between the input shaft 12 and the vibrator 20. By using the one-way clutch, even when an engagement control signal is output from the control unit 19 in a region where the relative speed between the input shaft 12 and the vibrator 20 is relatively large, the input shaft 12 and the vibrator are When the speed difference from 20 becomes small, both can be reliably engaged. That is, it is possible to perform control with a margin time (see FIG. 6) for the control delay.

  The brake 24 fixes the vibrator 20 to a fixing member (non-rotating member) such as a case. Similar to the clutch 22, the brake 24 is composed of one that can fasten / release the vibrator 20 at high speed. The brake 24 is composed of, for example, an electromagnetic brake that performs a fixing / releasing operation by intermittently supplying power to the electromagnet.

  The speed sensor 21 </ b> A measures the rotational speed (angular speed) of the input shaft 12. Further, the measured rotation speed is transmitted to the control unit 19. The speed sensor 21B measures the moving speed of the vibrator 20. Further, the measured moving speed is transmitted to the control unit 19.

  The control unit 19 controls the operation of the clutch 22 and the brake 24 according to the rotational speed of the input shaft 12 and the moving speed of the vibrator 20. The control unit 19 may be a computer, and the computer may be a computer storing an operation control program for a clutch 22 and a brake 24 described later, or an embedded computer. In addition, the control unit 19 includes an input interface to which the rotational speed of the input shaft 12 is input from the speed sensor 21A and the moving speed of the vibrator 20 is input from the speed sensor 21B.

  The control unit 19 controls the clutch 22 and the brake 24 by outputting a predetermined control signal. That is, the control unit 19 can engage / release the vibrator 20 and the input shaft 12 by controlling the clutch 22. Further, the control unit 19 can fix / release the vibrator 20 by controlling the brake 24.

  Next, transmission of driving force by the transmission member 16 will be described with reference to FIGS. In the following, it is assumed that the rotational speed of the input shaft 12 is faster than the rotational speed of the output shaft 14. As shown in FIG. 2, the elastic member 18 is urged around the axis in advance, and is elastically expanded and contracted along the axial direction of the output shaft 14. Accordingly, the vibrator 20 is also reciprocated along the axial direction of the output shaft 14.

  In order to place the elastic member 18 in a vibrating state when the driving force is transmitted, it is preferable that the elastic member 18 is in an urging state at a stage before transmission (standby stage). For example, as shown by a broken line in FIG. 4 described later, the vibrator 20 and the output shaft 14 are fixed in a state where the elastic member 18 is contracted.

  As shown in FIG. 3, the clutch 22 engages the input shaft 12 and the vibrator 20 in synchronization with the cycle of the reciprocating motion of the vibrator 20. That is, the driving force of the input shaft 12 is transmitted to the output shaft 14 in synchronization with the vibration cycle of the elastic member 18.

  By transmitting the driving force in synchronization with the vibration cycle of the elastic member 18, it is possible to transmit the driving force independent of the rotation cycle of the input shaft 12. Furthermore, by using the elastic member 18 whose vibration cycle is shorter than the maximum rotation cycle of the drive source, it becomes possible to transmit the drive force multiple times during one rotation of the input shaft 12. In addition, transmission of driving force is intermittently performed, but smooth transmission of driving force, such as PWM control, can be performed by performing this intermittent transmission at high speed (high frequency).

  As an example of the engagement between the input shaft 12 and the vibrator 20 in synchronization with the cycle of the reciprocating motion of the vibrator 20, the speed difference between the moving speed of the vibrator 20 and the rotational speed of the input shaft 12 becomes a predetermined value or less. Sometimes they are engaged. For example, when one speed is 80% or more and 120% or less of the other speed, both are engaged. Thus, by causing the input shaft 12 and the vibrator 20 to be engaged in a state where the speed difference is small, loss due to slippage during engagement is suppressed.

  More preferably, when the angular velocities of the vibrator 20 and the input shaft 12 are equal, both are engaged. The angular velocity of the vibrator 20 changes according to the elastic energy of the elastic member 18, and the angular velocity of the input shaft 12 and the vibrator 20 is twice in one cycle in which the vibrator 20 vibrates except for the extreme value of the angular velocity. Will be equal. At any one of the two times, the clutch 22 engages the input shaft 12 and the vibrator 20. By performing engagement when the angular velocities are equal, it is possible to prevent loss due to slipping.

  When the input shaft 12 and the vibrator 20 are engaged by the clutch 22, as shown in the upper to lower stages in FIG. 3, the speed difference between the input shaft 12 and the output shaft 14 (input shaft angular speed> output shaft angular speed) is determined. The elastic member 18 is contracted, and the elastic energy of the elastic member 18 is accumulated. That is, the driving energy of the input shaft 12 is converted into the elastic energy of the elastic member 18.

  Further, as shown in FIG. 4, the clutch 22 is released and the vibrator 20 is fixed by the brake 24. At this time, the elastic member 18 transmits the accumulated elastic energy to the output shaft 14. In other words, the elastic member 18 transmits the driving energy of the input shaft 12 to the output shaft 14 as a force. That is, as the vibrator 20 is fixed, the contracted elastic member 18 rotates (extrudes) the output shaft 14 in order to expand to the natural length. As described above, the driving force is transmitted from the input shaft 12 to the output shaft 14.

  Transmission of the driving force from the input shaft 12 to the output shaft 14 via the elastic member 18 can be expressed numerically as follows. For example, when the ratio between the angular velocity of the input shaft 12 and the angular velocity of the output shaft 14 is 5: 3, the input energy of 2/5, which is a differential component during engagement of the clutch 22, is elastic member 18 as elastic energy. And the remaining 3/5 of the energy is transmitted to the output shaft 14.

  The control unit 19 executes control for enabling the drive transmission as described above. The control unit 19 receives the rotational speed of the input shaft 12 and the moving speed of the vibrator 20 from the speed sensors 21A and 21B. Alternatively, instead of the measured speed, a calculated value calculated from the natural frequencies of the input shaft 12, the output shaft 14, and the elastic member 18 may be used.

  The control unit 19 controls the engagement of the vibrator 20 and the input shaft 12 by controlling the clutch 22 when the relative speed between the input shaft 12 and the vibrator 20 becomes a predetermined speed or less (elasticity). Energy storage control). Thereby, the elastic member 18 is contracted according to the speed difference between the input shaft 12 and the output shaft 14, and elastic energy is accumulated in the elastic member 18.

  When elastic energy is accumulated in the elastic member 18, the control unit 19 performs control to fix the vibrator 20 by the brake 24 after releasing the clutch 22 (elastic energy transmission control). The vibrator may be fixed by the brake 24 so as to be fixed when the speed of the vibrator with respect to the drive transmission device 10 becomes a predetermined value or less. As a result, the elastic member 18 extends, and the stored elastic energy is transmitted to the output shaft 14. As a result, the driving force is transmitted from the input shaft 12 to the output shaft 14.

  FIG. 5 illustrates speed changes of the input shaft 12, the vibrator 20, and the output shaft 14 accompanying the drive transmission described above. In the region indicated by A in FIG. 5, the vibrator 20 is released from the clutch 22 and the brake 24 and reciprocates along the axial direction of the output shaft 14. At this time, the maximum angular velocity of the vibrator 20 is higher than the angular velocity of the input shaft 12.

  When the angular velocity of the vibrator 20 and the angular velocity of the input shaft 12 are equal as in the region indicated by B in FIG. 5, the input shaft 12 and the vibrator 20 are engaged by the clutch 22. During the engagement, the vibrator 20 and the input shaft 12 are at the same speed.

  After the elastic energy is accumulated (shrinked) in the elastic member 18, the engagement by the clutch 22 is released (C in FIG. 5). Thereafter, the vibrator 20 is fixed by the brake 24, and the angular velocity of the vibrator 20 becomes 0 (D in FIG. 5). After the elastic energy of the elastic member 18 is transmitted to the output shaft 14, the brake 24 is released and the vibrator 20 reciprocates again (A in FIG. 5).

  FIG. 6 illustrates the angular velocity and torque change of the input shaft 12, the output shaft 14, and the vibrator 20. Note that L / U in the middle of the figure indicates engagement (Lock Up) of the clutch 22 or the brake 24, LU1 indicates engagement by the clutch 22, and LU2 indicates engagement by the brake 24.

  6, the torque received by the input shaft 12 from the transmission member 16 (input torque as viewed from the driving force transmission device 10) and the torque received by the output shaft 14 from the transmission member 16 (from the transmission member 16 to the output shaft 14). Shows the change in torque transmitted to. Hereinafter, the former is called input shaft torque, and the latter is called output shaft torque.

  When the input shaft 12 and the vibrator 20 are engaged by the clutch 22 (LU1: ON), the input shaft torque rises. When the clutch 22 is further disengaged (LU1: OFF) and the vibrator 20 is fixed to the brake 24 (LU2: ON), the elastic energy of the elastic member 18 is transmitted to the output shaft 14.

  When the upper stage and the lower stage in FIG. 6 are considered together, the output side angular velocity is lower than the input side angular velocity, and the output shaft torque is higher than the input shaft torque. When the inventor scrutinized this result, the ratio of the output side angular velocity to the input side angular velocity (gear ratio) was about 1/4, and the ratio of the output shaft torque to the input shaft torque (torque ratio) was about four times. It was.

  FIG. 7 shows an example of shifting with a gear ratio and torque ratio different from those in FIG. In addition, in the graph which shows the torque change of the lower stage of FIG. 7, the average value is also shown with the value of the output shaft torque. In the initial state (1), the transmission gear ratio between the input shaft 12 and the output shaft 14 is 1 / 1.3, and the torque ratio is 1.3. From this state, the angular velocity of the input shaft 12 is increased (2). At this time, the angular velocity change (amplitude) of the transducer 20 is increased so that the maximum angular velocity of the transducer 20 exceeds the angular velocity of the final input shaft (200 rad / s of (3)). Specifically, the engagement period of the clutch 22 is lengthened (LU1 → long), and the vibrator 20 is pulled. Alternatively or additionally, the engagement period of the brake 24 is shortened (LU2 → short), and the allocation of elastic energy to vibration of the elastic member 18 is increased. By doing so, the amplitude of the elastic member 18 is increased.

  Further, when the angular velocity of the vibrator 20 reaches a desired angular velocity, the clutch 22 is engaged to accumulate the elastic energy of the elastic member 18, and the clutch 22 is released to engage the brake 24 to output the output shaft 14. The elastic energy is transmitted to (3). In the example (3), the gear ratio is 1 / 2.5 and the torque ratio is 2.5.

  As described above, in this embodiment, the transmission gear ratio and the torque ratio of the input shaft 12 and the output shaft 14 are changed by changing the amplitude of the vibrator 20, the engagement period of the clutch 22, and the engagement period of the brake 24. Can be made. Such a shift can be performed steplessly (continuously) in principle. That is, the stepless speed change is possible with a simple structure as shown in FIG.

  It should be noted that the amplitude of the vibrator 20, the engagement period of the clutch 22, and the engagement period of the brake 24 for obtaining the desired gear ratio and torque ratio are not limited to one value. For example, FIGS. 8 and 9 show examples in which the same gear ratio and torque ratio are obtained by changing the conditions of the above three parameters.

  In FIG. 8, the amplitude of the vibrator 20 is reduced compared to FIG. 9, but the engagement period (LU1) of the clutch 22 and the engagement period (LU2) of the brake 24 are longer than those of FIG. It is set. Thus, even if the conditions of the amplitude of the vibrator 20, the engagement period of the clutch 22 and the engagement period of the brake 24 are variously changed, the same gear ratio and torque ratio can be obtained.

  8 and 9 are compared, the variation in the output shaft torque is larger in FIG. 9 where the engagement period of the clutch 22 is shorter. This point will be described with reference to FIG. FIG. 10 shows the change in the output shaft torque when the engagement period of the clutch 22 is changed. According to this, as the clutch engagement period becomes longer, the fluctuation range of the output shaft torque becomes smaller.

  Thus, from the viewpoint of suppressing fluctuations in the output shaft torque, it is preferable that the engagement period of the clutch 22 is long. On the other hand, when the elastic member 18 having a large amplitude with respect to predetermined elastic energy is used, such as a small spring coefficient, the engagement period of the clutch 22 has to be shortened as shown in FIG. Therefore, in such a case, it is preferable to connect a plurality of driving force transmission devices 10 and determine the engagement period of the clutch 22 in a complementary manner. FIG. 11 shows a torque change when the two driving force transmission devices 10 are arranged on the same axis of the input shaft 12. The input shaft torque is multiphased, and as a result, the output shaft torque is smoothed.

  The control unit 19 performs the continuously variable transmission control as described above. The control unit 19 has an input interface (or signal line) for inputting a required speed ratio and required torque ratio (request information) of the output shaft 14 to the input shaft 12. Further, the control unit 19 stores a table (table) in which the transmission ratio and the torque ratio, the amplitude of the vibrator 20, the engagement period of the clutch 22 and the engagement period of the brake 24 are associated with each other in a storage unit (not shown). ing. Such a table shows the relationship between the gear ratio and torque ratio of the input shaft 12 and the output shaft 14 when the amplitude of the vibrator 20, the engagement period of the clutch 22 and the engagement period of the brake 24 are variously changed. Can be obtained by actual measurement or calculation. Note that an algorithm or function corresponding to the table may be stored instead of the table.

  The control unit 19 obtains the amplitude of the vibrator 20, the engagement period of the clutch 22, and the engagement period of the brake 24 by referring to the table based on the required speed ratio and the required torque ratio input from the input interface. Next, the clutch 22 and the brake 24 are controlled based on the acquired amplitude of the vibrator 20, the engagement period of the clutch 22, and the engagement period of the brake 24.

  Next, a specific configuration of the driving force transmission device 10 according to the present embodiment will be described. FIG. 12 is a schematic diagram in which main elements are extracted from the specific configuration of the driving force transmission device 10. In this figure, the transmission member 16 and the output shaft 14 are arranged along the axial direction of the input shaft 12.

  The transmission member 16 includes a clutch 22, a brake 24, an elastic member 18, and a transmission shaft 26. The clutch 22 is provided at the axial end of the transmission shaft 26 so as to be engageable with the flange at the axial end of the input shaft 12. A brake 24 is provided at the axial center of the transmission shaft 26. Further, an elastic member 18 is provided at the other end of the transmission shaft 26 facing the end where the clutch 22 is provided. The elastic member 18 is connected to the transmission shaft 26, and the transmission shaft 26 is reciprocated in the axial circumferential direction as the elastic member 18 vibrates. Therefore, the transmission shaft 26 corresponds to the vibrator 20 shown in FIG.

  FIG. 13 illustrates a specific configuration of FIG. The input shaft 12, the transmission shaft 26, and the output shaft 14 are coaxially arranged. The input shaft 12 and the transmission shaft 26 are rotatably supported by the base 30 via bearings 28.

  A flange 32 is formed on the input shaft 12 so as to project in the radial direction. The clutch 22 is provided so as to sandwich the flange 32. The clutch 22 includes a movable part 22A and an excitation part 22B.

  The excitation unit 22B receives an excitation current from a power source (not shown), thereby generating a magnetic flux. The exciting portion 22B is an annular member, and is fixed to the base 30 so as to be separated from the input shaft 12 and the transmission shaft 26.

  The movable portion 22A is an annular member made of a magnetic material such as metal, and is movable according to the magnetic flux generated from the exciting portion 22B. The movable portion 22A is coupled to the transmission shaft 26 via a fastening portion 34 that is screwed into the movable portion 22A in the axial direction. The length of the shaft portion 36 of the fastening portion 34 is formed longer than the axial thickness of the input side flange 38 of the transmission shaft 26. With such a structure, the movable portion 22A is fixed in the axial circumferential direction with respect to the transmission shaft 26 and is movable in the axial direction. When a magnetic flux is generated in the exciting portion 22B, the movable portion 22A is attracted in the axial direction and engaged with the flange 32 of the input shaft 12.

  The transmission shaft 26 includes an input side flange 38, an intermediate flange 40, and an output side flange 42. These flanges are respectively formed on the transmission shaft 26 along the axial direction from the input shaft 12 toward the output shaft 14. When the movable portion 22 </ b> A of the clutch 22 provided on the input side flange 38 is engaged with the input shaft 12, the transmission shaft 26 rotates in synchronization with the input shaft 12.

  The elastic member 18 is connected to the output flange 42. The elastic member 18 is disposed in a slot 44 provided around the axis of the output shaft 14, one end along the extending direction of the slot 44 is connected to the output side flange 42, and the other end is connected to the output shaft 14. Has been. When the transmission shaft 26 is engaged with the input shaft 12, the transmission shaft 26 urges the elastic member 18 to contract.

  The intermediate flange 40 is provided with a brake 24. As with the clutch 22, the brake 24 includes a movable portion 24A and an exciting portion 24B so as to sandwich the intermediate flange 40. The movable portion 24 </ b> A is movable only in the axial direction with respect to the base 30. When a magnetic flux is generated in the exciting portion 24B, the movable portion 24A is attracted in the axial direction and engaged with the transmission shaft 26. Thereby, the rotation of the transmission shaft 26 is stopped.

  Transmission of driving force from the input shaft 12 to the output shaft 14 is performed as follows. First, when the input shaft 12 and the transmission shaft 26 are engaged by the clutch 22, both rotate synchronously. By this synchronous rotation, the elastic member 18 connected to the transmission shaft 26 is contracted. Furthermore, the elastic member 18 transmits elastic energy to the output shaft 14 by releasing the clutch 22 and fixing the transmission shaft 26 by the brake 24. As a result, driving force is transmitted from the input shaft 12 to the output shaft 14.

  In the above-described embodiment, an example of drive transmission in the case where the rotational speed of the input shaft 12 is faster than the rotational speed of the output shaft 14 is described, but the present invention is not limited to this form. For example, the driving force transmission device 10 according to the present embodiment can perform drive transmission when the rotational speed of the input shaft 12 is slower than the rotational speed of the output shaft 14. 14 and 15 are time charts of driving force transmission when the rotational speed of the input shaft 12 is slower than the rotational speed of the output shaft 14. In FIG. 14, the clutch 22 is engaged / released while the vibrator 20 is accelerating (spring extension <natural length), and the brake 24 is used while the vibrator 20 is decelerating (spring extension> natural length). Fixed / open. In FIG. 15, the clutch 22 is engaged / released during acceleration of the vibrator 20, the brake 24 is fixed during acceleration of the vibrator 20, and the brake 24 is further accelerated during acceleration of the vibrator 20. Opening.

  Moreover, in the above-mentioned embodiment, although the elastic member 18 and the vibrator | oscillator 20 were provided in the output shaft 14, it is not restricted to this form. 16 and 17 show time charts of driving force transmission when the elastic member 18 and the vibrator 20 are provided on the input shaft 12 instead of the output shaft 14. 16 and 17 show an example in which the rotational speed of the input shaft 12 is faster than the rotational speed of the output shaft 14. In FIG. 16, the clutch 22 is engaged / released during acceleration of the vibrator 20 and is fixed / released by the brake 24 during deceleration of the vibrator 20. In FIG. 17, the clutch 22 is engaged / released while the vibrator 20 is accelerating, and is fixed by the brake 24 while the vibrator 20 is decelerated. Opening.

  18 and 19 show another example of power transmission of the driving force transmission device 10 according to the present embodiment. In this example, an example of power transmission in the case where the input shaft 12 and the output shaft 14 are rotating in opposite directions is shown.

  FIG. 18 shows a timing chart of the power transmission device 10. The upper graph shows the transition of the angular velocities of the input shaft 12, the vibrator 20, and the output shaft 14. The vertical axis represents angular velocity, and the horizontal axis represents time. As shown in this figure, it is understood that the input shaft 12 and the output shaft 14 straddle the speed 0 line, and both are rotating in reverse.

  The graph in the middle of the figure shows the torque of the output shaft 14 and the elongation of the elastic member 18. The vertical axis represents the vibration displacement of the elastic member 18. Note that the output torque of the output shaft 14 is obtained by multiplying the vibration displacement by a spring constant. The horizontal axis represents the time synchronized with the upper graph.

  Further, the lower graph in the figure shows the engagement timing (lock-up timing) of the clutch 22 and the brake 24 of the transmission member 16. The vertical axis represents the percentage of engagement, where 0 is open and 1 (= 100%) is the state of complete engagement. The horizontal axis represents the time synchronized with the upper and middle graphs.

  FIG. 19 is an enlarged graph in which one cycle of power transmission of the transmission member 16 is extracted from the upper graph in FIG. The starting point is time t11 when the absolute speed of the vibrator 20 (vibration of the elastic member 18 + rotation of the output shaft 14) is zero. As the elastic member 18 contracts, the vibrator 20 moves in the same direction as the input shaft 12 (first rotation axis). At time t12, the elastic member 18 has a natural length (the length of the elastic member 18 when the amplitude velocity component of the vibrator 20 reaches the maximum value), and the absolute speed of the vibrator 20 that decelerates as the elastic member 18 contracts further is reduced. The rotational speed of the input shaft 12 becomes equal at time t13. At this time, the vibrator 20 and the input shaft 12 are engaged by the clutch 22 (first state). Since the relative speed between the two is 0, no slip occurs in theory.

  When the vibrator 20 and the input shaft 12 are engaged with each other, the input shaft 12 and the output shaft 14 (second rotation shaft) are rotated in the reverse direction. In other words, the elastic member 18 in a state in which the output shaft 14 can be urged in the direction opposite to the rotation direction of the output shaft 14 is further contracted. That is, the elastic energy is accumulated in the elastic member 18 by the urging of the input shaft 12 and the output shaft 14 (time t13 to t14).

  When the engagement by the clutch 22 is released at the time t14 (second state), the vibrator 20 further contracts and becomes the same speed as the output shaft 14 at the time t15. That is, the elastic member 18 is shrunk and the vibration speed of the vibrator 20 becomes zero. Thereafter, the vibrator 20 is moved in the opposite direction to the input shaft 12 (in the forward direction from the output shaft 14) by the extension movement of the elastic member 18. At time t <b> 16, the elastic member 18 has a natural length, and the vibrator 20 is moved in the direction in which the elastic member 18 extends, that is, the rotation direction of the output shaft 14.

  When the absolute speed of the vibrator 20 becomes zero at time t17, the vibrator 20 is engaged with a fixing member (non-rotating member) such as a case via the brake 24 (third state). Since the relative velocity of both (vibrator 20 and case) is 0, no slip occurs theoretically.

  At this time, the elastic member 18 that has extended beyond the natural length, in other words, capable of urging the output shaft 14 in the rotation direction of the output shaft 14 contracts to attract the output shaft 14 (time t17 to t18). ). Since the pulling direction is the same as the rotation direction of the output shaft 14, the elastic energy of the elastic member 18 becomes a torque in the forward direction with respect to the rotation direction of the output shaft 14 and biases the output shaft 14. In other words, the elastic energy of the elastic member 18 is released to the output shaft 14. After the release of the elastic energy, the engagement by the brake 24 is released (fourth state), and the operation proceeds to the same operation at time t11 (= t18).

  Thus, in this embodiment, elastic energy is stored in the elastic member 18 by urging the elastic member 18 from the input shaft 12 and the output shaft 14 at times t13 to t14. Furthermore, at least a part of the torque transmitted from the output shaft 14 is returned from the elastic member 18 to the output shaft 14 at times t17 to t18. In other words, in this embodiment, torque transmission from the input shaft 12 to the output shaft 14 is performed through cancellation of energy transmission between the elastic energy of the elastic member 18 and the torque of the output shaft 14.

  18 and 19, the clutch 22 and the brake 24 are engaged at the timing when the absolute speed of the vibrator 20 and the rotational speed of the input shaft 12 are completely matched, or when the absolute speed of the vibrator 20 is complete. However, the present invention is not limited to the point of time when it becomes zero, and it is sufficient that the loss due to the slip is negligible in view of input / output energy. For example, when one speed is 80% or more and 120% or less of the other speed, both may be engaged.

  10 driving force transmission device, 12 input shaft, 14 output shaft, 16 transmission member, 18 elastic member, 20 vibrator, 22 clutch, 24 brake.

Claims (1)

A first rotating shaft that rotates in one direction ;
A second rotating shaft that rotates in a direction opposite to the first rotating shaft;
An elastic member;
A vibrator,
With
One end of the elastic member is fixed to the second rotating shaft,
The other end of the elastic member is fixed to the vibrator,
The vibrator includes a first state connected to the first rotating shaft, a second state where the connection is released, a third state where the vibrator is fixed to a fixing member, and a fourth state where the fixing is released. Can be in any of the states
When the elastic member can bias the second rotating shaft in a direction opposite to the rotating direction of the second rotating shaft, the vibrator is in the first state, and the first rotating shaft and the Elastic energy that urges the elastic member in the reverse direction is further accumulated in the elastic member by two rotation shafts,
When the elastic member can bias the second rotation shaft in the rotation direction of the second rotation shaft, the vibrator enters the third state, and biases the second rotation shaft in the rotation direction. A driving force transmission device in which elastic energy of the elastic member is released.

Images