JPH08149792A - Launching system - Google Patents

Abstract

PURPOSE: To decrease the coupling capacity in a low r.p.m. region and to increase the coupling capacity in a high r.p.m. region. CONSTITUTION: The launching system comprises a magnetic coupling, a launching clutch member for receiving the rotation of an engine through the magnetic coupling upon engaging therewith to transmit the rotation to a transmission, and a speed change clutch member for receiving the rotation of the engine directly upon engagement to transmit the rotation to the transmission. The magnetic coupling comprises an annular permanent magnet 32, and an annular driven member 33 disposed oppositely to the permanent magnet 32 through a small gap. The driven member 33 comprises a secondary conductive member 86 arranged annularly, and a first annular iron plate 85 arranged on the back of the secondary conductive member 86. The secondary conductive member 86 comprises a first conductive member, and a second conductive member arranged to come into contact freely with the first conductive member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starting device.

[0002]

2. Description of the Related Art Conventionally, in a manual transmission for a vehicle,
A starting device is disposed between the engine and the transmission, and the starting device intermittently connects the engine and the transmission to allow torque to be selectively transmitted to the transmission. In this case, in the starting device, a dry single-plate clutch plate is arranged between the flywheel to which torque is transmitted and the pressure plate, and the friction plate is arranged on the clutch plate. The flywheel and the pressure plate are disengaged by selectively sandwiching the clutch plate by the flywheel and the pressure plate.

[0003]

However, in the above-described conventional starting device, when a friction plate having a high friction coefficient is used, the clutch plate and the pressure plate can be engaged while sliding the friction plate. Can not. Therefore,
When the engine and the transmission are connected by the starter, the engine speed and the input side speed of the transmission momentarily become equal to each other, causing a shock.

On the other hand, when a friction plate having a low coefficient of friction is used, the clutch plate and the pressure plate can be engaged while sliding the friction plate. There is no shock when connected. However, since the torque capacity of the starting device becomes small, it is necessary to dispose a plurality of friction plates to increase the number of plates. As a result, the weight of the starting device is increased, the inertia of the input side of the transmission is increased, the load on the synchronization mechanism of the transmission is increased, and the time until the transmission is synchronized becomes longer.

Therefore, a shock does not occur when the engine and the transmission are connected, the load on the synchronization mechanism of the transmission can be reduced, and the time taken for the transmission to synchronize can be shortened. A starting device is provided (see Japanese Patent Application No. 5-355299). In the starting device, the input shaft of the transmission is connected to the speed change clutch member, the output shaft of the engine is connected to the start clutch member, and the torque transmission member is interposed between the speed change clutch member and the start clutch member. Is rotatably disposed so that the shift clutch member and the start clutch member can be engaged and disengaged. Further, the torque transmission member can be rotated by the magnetic drag force generated by the rotation of the engine.

In this case, for example, when the shift clutch member and the torque transmission member are engaged with each other while the clutch pedal is slightly depressed, the torque of the engine is transmitted to the torque transmission member by the magnetic drag, and the half torque is transmitted. A clutch condition is established. Further, when the clutch pedal is returned to the original position and the starting clutch member, the speed change clutch member and the torque transmission member are engaged with each other, the torque of the engine is directly transmitted to the input shaft of the transmission and the clutch engagement state is formed. .

In this type of starting device, a magnetic coupling is used to generate the magnetic drag. The magnetic coupling is a permanent magnet mounted on the output shaft side of the engine, and a core material mounted on the torque transmission member side and having a secondary conductive material and a rear surface of the secondary conductive material. And a drive member. Further, the permanent magnet and the secondary conductive material are opposed to each other with a slight gap (gap) so that the magnetic flux generated by the permanent magnet links the secondary conductive material. Then, when the rotation from the engine is transmitted to rotate the permanent magnet, the amount of the magnetic flux linking the secondary conductive material changes, and the secondary conductive material is electromagnetically induced by the electromagnetic induction corresponding to the change amount of the magnetic flux. Eddy current flows.
As a result, a magnetic drag is generated by the interaction between the eddy current and the magnetic flux, and the secondary conductive material is rotated.

The magnetic coupling may be composed of a drive member mounted on the output shaft side of the engine and a permanent magnet mounted on the torque transmission member side. By the way, the rotational speed and the torque transmitted by utilizing electromagnetic induction change logarithmically. Therefore, when the shift clutch member is engaged when the engine is in the idling state, the torque that can be transmitted by the coupling (hereinafter referred to as "coupling capacity") becomes larger than the torque capacity of the engine, and the engine stall occurs. It may happen.

The present invention solves the problems of the conventional starting device, and has a torque transmission characteristic that the coupling capacity is small in the low rotation speed region and the coupling capacity is large in the high rotation speed region. An object is to provide a starting device.

[0010]

To this end, in the starting device of the present invention, a magnetic coupling for transmitting torque by a magnetic drag force and a disengageably disposed magnetic coupling are used to prevent the engine from rotating when the engine is rotated. It has a starting clutch member that is received via a coupling and is transmitted to the transmission, and a transmission clutch member that is disengageably disposed and that directly receives rotation of the engine when engaged and transmits it to the transmission.

The magnetic coupling has an annular permanent magnet formed by alternately arranging magnetic poles different from each other, and an annular permanent magnet arranged to face the permanent magnet with a slight gap. And a driven member. Further, the driven member is composed of a secondary conductive member arranged in an annular shape and an annular iron plate arranged on the back surface of the secondary conductive member.

Further, the secondary conductive member can come into contact with the first secondary conductive material by thermal expansion of the first secondary conductive material and Joule heat generated in the first secondary conductive material. And a second secondary conductive material disposed on the.

[0013]

According to the present invention, according to the present invention, as described above, in the starting device, the magnetic coupling for transmitting the torque by the magnetic resistance is disengageably disposed, and the rotation of the engine at the time of engagement is prevented. It has a start clutch member that is received via the magnetic coupling and is transmitted to the transmission, and a shift clutch member that is disengageably disposed and that directly receives rotation of the engine when engaged and transmits it to the transmission.

The magnetic coupling has an annular permanent magnet formed by alternately arranging magnetic poles different from each other, and an annular permanent magnet arranged to face the permanent magnet with a slight gap. And a driven member. The driven member includes an annular secondary conductive member and an annular iron plate arranged on the back surface of the secondary conductive member. Further, the secondary conductive member includes a first secondary conductive material and the first secondary conductive material.
Of the second conductive material, which is disposed so as to come into contact with the first secondary conductive material, by thermal expansion due to Joule heat generated in the secondary conductive material.
Secondary conductive material.

In this case, when the clutch pedal is depressed,
The starting clutch member, the speed change clutch member, and the torque transmission member are released, and the clutch released state is formed. Next, when the clutch pedal is gradually returned, the engagement between the speed change clutch member and the torque transmission member is started, and the half-clutch state is formed. At this time, the torque of the engine is transmitted to the transmission by the magnetic resistance.

Then, when the engagement of the shift clutch member is completed, the engagement of the starting clutch member is started, and when the engagement of the starting clutch member is completed, the clutch engagement state is formed. By the way, when the engine speed is low while the half-clutch state is formed, the magnetic flux generated by the permanent magnets links the first secondary conductive material to generate an eddy current.

At this time, a part of the magnetic flux generated by the permanent magnets links the second secondary conductive material, but the second secondary conductive material and the first secondary conductive material. Since a gap is formed between the second and second conductive materials, a sufficient amount of eddy current does not flow in the second secondary conductive material. Therefore, the eddy current generated in the entire secondary conductive member is relatively small, and the torque that can be transmitted is correspondingly small.

As a result, the idling torque transmitted from the engine becomes larger than the coupling capacity, so that engine stall does not occur. Next, when the driver depresses the accelerator pedal to increase the engine rotation speed, the difference between the rotation speed of the permanent magnet and the rotation speed of the driving member increases, and the first secondary conductive material is generated. The eddy current generated becomes large, and the Joule heat generated by the eddy current gradually increases.

Then, the first secondary conductive material expands due to the Joule heat, the gap between the first secondary conductive material and the second secondary conductive material disappears, and the first secondary conductive material disappears. The second conductive material and the second conductive material are integrated. In this case, since no gap is formed, an eddy current flows through the entire secondary conductive member. And
The eddy current is larger than the eddy current flowing only in the first secondary conductive material, and the coupling capacitance is correspondingly larger.

[0020]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 2 is a sectional view of the starting device in the first embodiment of the present invention. As shown in the figure, the starting device is arranged between an output shaft (crankshaft) 11 of the engine (not shown) and an input shaft 10 of the transmission (not shown), and connects the engine and the transmission in response to a command signal. Let The rotation of the engine is transmitted to the transmission through the starting device, the speed is changed in the transmission, the differential is generated in the differential device (not shown), and the drive wheel is transmitted to the left and right driving wheels (not shown). In the transmission, a specific gear ratio can be set by selecting a plurality of gear sets that are arranged on two parallel shafts and have different gear ratios.

In the starting device, the output shaft 11
A starting clutch member 14 is connected to the vehicle via a disc-shaped flywheel 12. The starting clutch member 14 is attached to the output shaft 1 together with the flywheel 12 by a bolt 16.
1, a clutch hub 18 fixed to the end surface of the clutch hub 18, a leaf spring 19 fixed to the outer circumference of the clutch hub 18, and the leaf spring 1
It comprises friction plates 21 fixed on both sides of the plate 9. A bearing 24 is arranged on the outer circumference of the boss portion 22 of the flywheel 12, and the torque transmission member 26 is supported by the bearing 24 so as to be rotatable relative to the output shaft 11. The leaf spring 19 urges both friction plates 21 away from each other to form a compression margin.

The torque transmission member 26 is a clutch wheel 27 arranged to face the flywheel 12 radially outward of the bearing 24, and an annular ring arranged on the outer peripheral edge of the clutch wheel 27. Clutch cover 3 fixed to clutch wheel 27 together with outer ring 29 by outer ring 29 and bolt 30
1. The outer ring 29 and the return spring 3 are arranged radially inward of the outer ring 29 so as to sandwich the starting clutch member 14 together with the clutch wheel 27.
6, a metal intermediate pressure plate 35, and a pressure plate 37 disposed radially inward of the clutch cover 31 with the intermediate pressure plate 35 sandwiching the transmission clutch member 15. The return spring 36 urges the intermediate pressure plate 35 and the clutch wheel 27 away from each other to release the starting clutch member 14 and the torque transmission member 26.

In this embodiment, the bearing 2
Although the torque transmission member 26 is rotatably supported by the output shaft 11 by means of 4, the torque transmission member 26 may be rotatably supported by the starting device casing 23 by a bearing (not shown). Further, the flywheel 12 has a property as a ferromagnetic material. Plural pairs of permanent magnets 32 are fitted on the surface of the flywheel 12 facing the clutch wheel 27. As a result, the magnetic flux generated by the permanent magnet 32 links the driven member 33. The permanent magnets 32 are arranged in the circumferential direction of the flywheel 12, and have S poles, N poles,
Different magnetic poles such as S pole, N pole, ... Are adjacent to each other. As the permanent magnet 32, a ferrite magnet, a samarium cobalt magnet having high heat resistance, or the like can be used.

On the other hand, on the surface of the clutch wheel 27 facing the flywheel 12, an annular driven member 3 is provided.
3 is inserted. The driven member 33 is composed of a non-magnetic first secondary conductive material, a second secondary conductive material, and a magnetic material. As the first secondary conductive material and the second secondary conductive material, Copper, aluminum, etc. can be used. The permanent magnet 32 and the driven member 33 constitute a magnetic coupling.

By the way, when the engine rotates at a low speed in the idling state or the like, the amount of magnetic flux interlinking the driven member 33 changes, and the driven member 33 is changed in response to the amount of change in the magnetic flux. Eddy current flows due to electromagnetic induction. Therefore, due to the interaction between the eddy current and the magnetic flux of the permanent magnet 32, a magnetic drag force is generated between the torque transmission member 26 and the flywheel 12, and the driven member 33 is rotated.

The magnetic resistance changes according to the difference between the rotational speed of the torque transmission member 26 and the rotational speed of the flywheel 12. In this case, when the difference between the rotational speeds of the two becomes greater than a predetermined value, the magnetic drag decreases. Further, the shift clutch member 15 is disposed at an end of the input shaft 10 of the transmission via a damper 41, and the intermediate pressure plate 35 is provided.
Is opposed to. The damper 41 includes the input shaft 10
It is fixed to the damper hub 45 which is spline-connected.
The damper 41 is for smoothing the fluctuation of the torque transmitted to the input shaft 10 via the starting clutch member 14 and the speed change clutch member 15, is connected to the speed change clutch member 15, and is connected to the speed change clutch member 15. First member 42 to which torque is transmitted via 15, second member 43 connected to damper hub 45, and first member 42 and second member 43
It consists of a damper spring 44 disposed between and. The torque is based on the starting clutch member 14 and the shift clutch member 1.
5 and the damper 41, the damper spring 44 of the damper 41 is transmitted to the input shaft 10 in response to the torque fluctuation.
Expands and contracts.

The speed change clutch member 15 comprises a plate 47 fixed to the outer periphery of the first member 42, and friction plates 49 fixed to both surfaces of the plate 47. The pressure plate 37 is connected to the clutch cover 31 via the strap 51 at the protrusion 50 formed on the outer peripheral edge of the pressure plate 37. The clutch cover 31 has a support portion 55 on the end surface on the transmission side (not shown), and the diaphragm spring 57 is clamped and held by the support portion 55. The diaphragm spring 57 is formed of an annular body, the outer peripheral edge of which contacts the pressure plate 37, and the inner peripheral edge of which contacts the release bearing 58. Reference numeral 59 is a holding spring which is fixed to the pressure plate 37 by a bolt 60 and presses the outer peripheral edge of the diaphragm spring 57 against the pressure plate 37.

Therefore, the release bearing 58
Since the outer peripheral edge of the diaphragm spring 57 can also move in the axial direction as the shaft moves in the axial direction, the pressure plate 37 disengages the transmission clutch member 15 and the torque transmission member 26, and the start clutch member 14 moves. Also, the shift clutch member 15 and the torque transmission member 26 can be disengaged from each other.

The release bearing 58 is the input shaft 1
A sliding member 6 which surrounds 0 and is slidably attached to the sleeve 63 fixed to the starting device casing 23 and slidable on the outer periphery of the sleeve 63.
4 and the bearing body 65, and the inner race of the bearing body 65 projects toward the engine side in the axial direction and is brought into contact with the inner peripheral edge of the diaphragm spring 57.

Further, a release fork 68 is arranged to move the release bearing 58 in the axial direction. An inner end of the release fork 68 is opposed to an end surface of the release bearing 58 on the transmission side, and an outer end of the release fork 68 extends in a direction perpendicular to the input shaft 10 and the starter casing 2
3 and is opposed to the rod 71 of the release cylinder 70 outside the starting device casing 23.
The release fork 68 has a linear return spring (not shown).

The release cylinder 70 comprises a return spring 75, a piston 76 and a rod 71. The piston 76 is actuated by hydraulic pressure and the rod 71 moves the outer end of the release fork 68. The release cylinder 70 is connected to a master cylinder (not shown) by an oil passage. Then, the master cylinder is further connected to a clutch pedal (not shown). When the driver depresses the clutch pedal, the master cylinder is operated, the hydraulic pressure generated by the master cylinder is supplied to the release cylinder 70, and the rod 71 can be moved forward (moved to the left in the figure). it can. On the other hand, when the clutch pedal is returned, the hydraulic pressure in the release cylinder 70 can be supplied to the master cylinder and the rod 71 can be retracted (moved to the right in the figure).

By the way, the diaphragm spring 5 is
The urging force applied to the pressure plate 37 by the 7 is the starting clutch member 1
4 and the speed change clutch member 15 and the torque transmission member 26 are engaged with each other so as to correspond to a force capable of sufficiently transmitting torque between the output shaft 11 of the engine and the input shaft 10 of the transmission. . A locking member 82 surrounding the inner end of the release fork 68 is attached to the release bearing 58, and the inner end of the release bearing 58 and the release fork 68 are locked via the locking member 82. .

When the outer end of the release fork 68 is pushed to the left in the figure by the forward movement of the rod 71, the release fork 68 swings around the support member 73 as a fulcrum and is pushed by the principle of leverage. The pressure and stroke are adjusted, the inner end of the release fork 68 is moved to the right in the figure, and the diaphragm spring 5
The release bearing 58 is pushed while overcoming the biasing force of 7.

The movement of the release bearing 58 moves the inner peripheral edge of the diaphragm spring 57 in the same direction, and the diaphragm spring 57 is swung to move the outer peripheral edge to the left in the figure. As a result, the urging force of the diaphragm spring 57 on the pressure plate 37 is reduced or released, and the pressure plate 37 is moved leftward in the drawing.

On the other hand, when the outer end of the release fork 68 is returned to the right in the figure, the release fork 68 swings around the support member 73 as a fulcrum and moves the inner end to the left in the figure. At this time, the release bearing 58 is moved leftward in the figure by the urging force of the diaphragm spring 57, and the outer peripheral edge of the diaphragm spring 57 presses the pressure plate 37. Then, as the pressing force increases, the pressure plate 37 first engages the speed change clutch member 15 and the torque transmission member 26, and subsequently, the starting clutch member 14, the speed change clutch member 15 and the torque transmission member 26.
Engage and.

Next, the operation of the starting device having the above construction will be described with reference to FIGS. FIG. 3 is a clutch released state diagram in the first embodiment of the present invention, FIG. 4 is a half clutch state diagram in the first embodiment of the present invention, and FIG. 5 is a clutch engagement state in the first embodiment of the present invention. FIG. 6 is a torque capacity characteristic diagram of the starting device according to the first embodiment of the present invention, and FIG. 7 is a pressing load characteristic diagram of the starting device according to the first embodiment of the present invention. In FIG. 6, the horizontal axis represents the release stroke and the vertical axis represents the torque capacity. In FIG. 7, the horizontal axis represents the release stroke and the vertical axis represents the pressing load.

In the clutch released state, the clutch pedal is depressed, the pressure plate 37 is moved to the left in the figure as shown in FIG. 3, and the starting clutch member 14 is moved.
The shift clutch member 15 and the torque transmission member 26 are released. At this time, the friction plate 4 of the speed change clutch member 15
9 does not contact either the pressure plate 37 or the intermediate pressure plate 35. Further, the friction plate 21 of the starting clutch member 14 is the intermediate pressure plate 3
Neither 5 nor the clutch wheel 27 contacts. At this time, as shown in FIG. 6, the torque capacity of the starting device is “0”.
Is.

Reference numeral 12 is a flywheel, 19 is a leaf spring, 32 is a permanent magnet, 33 is a driven member, and 36 is a return spring. Next, the clutch pedal is gradually returned, and as shown in FIG. 4, the friction plate 49 and the pressure plate 37 are
Further, when the friction plate 49 and the intermediate pressure plate 35 come into contact with each other, the engagement between the speed change clutch member 15 and the torque transmission member 26 is started, and the half clutch state is formed. At this time,
Since the engine (not shown) is in the idling state and the flywheel 12 is rotated at a low speed, torque is transmitted from the flywheel 12 to the clutch wheel 27 by magnetic drag. In this case, the clutch wheel 27 has a lower rotation speed than the flywheel 12. In this way, the torque transmitted to the clutch wheel 27 is transmitted to the transmission (not shown) via the transmission clutch member 15.

At this time, since the release stroke is reduced, the diaphragm spring 57 (FIG. 2) connects the pressure plate 37 and the friction plate 49, and the friction plate 49.
While sliding the intermediate pressure plate 35 and the clutch wheel 2
7 and then the engagement between the shift clutch member 15 and the torque transmission member 26 is terminated. During this period, the torque capacity increases and changes from the value at point P _{1 to} the value at point P ₂ in FIG. Further, the pressing load also increases, and changes from the value at the point Q _{1 to} the value at the point Q ₂ along the return spring load line L1 in FIG.

Next, when the release stroke is further reduced, the intermediate pressure plate 35 moves to the clutch wheel 27 side against the biasing force of the return spring 36, and the friction plate 2
1 and the intermediate pressure plate 35, and the friction plate 21 and the clutch wheel 27 come into contact with each other, and the engagement between the torque transmission member 26 and the starting clutch member 14 is started. During that time, since the torque transmitted by the magnetic coupling does not change, the torque capacity is constant, and the value of point P ₂ and point P _{2 in} FIG.
It is equal to the value of ₃ . On the other hand, the pressing load increases because the return spring 36 contracts, and changes from the value at the point Q _{2 to} the value at the point Q ₃ along the return spring load line L1 in FIG.

As described above, in the control range A, the torque capacity can be kept constant. Therefore, when the transmission is set to the first forward speed (the gear stage having the largest gear ratio when moving forward), the torque can be transmitted to the transmission to start the vehicle. Since the clutch wheel 27 and the flywheel 12 are not directly connected to each other, even if the shift clutch member 15 and the clutch wheel 27 are stopped when the half-clutch state is formed, the engine will not stall. .

In the half-clutch state, the torque corresponding to the magnetic drag can be transmitted to the transmission. Therefore, since the vehicle can be made to creep by the torque transmitted to the transmission, it is possible to easily start the vehicle on an uphill road. Next, when the release stroke is further reduced, the intermediate pressure plate 35
Against the urging force of the return spring 36
The intermediate pressure plate 35 and the friction plate 21 and the clutch wheel 27 are further slid to the clutch wheel 27 side. Then, as shown in FIG.
, The engagement between the torque transmission member 26 and the starting clutch member 14 is terminated. During that time, the torque capacity increases, and changes from the value at point P _{3 to} the value at point P ₄ in FIG. Further, the pressing load also increases, and changes from the value at point Q _{3 to} the value at point Q ₄ along the shift clutch load line L2 in FIG. At this time, the clutch engagement state is formed. In addition,
L3 is a starting clutch load line.

In the clutch engaged state, the speed change clutch member 15, the starting clutch member 14 and the torque transmitting member 26 are engaged with each other, and the rotation of the flywheel 12 is performed by the torque transmitting member 2 via the starting clutch member 14.
6 is directly transmitted. Therefore, the clutch wheel 2
There is no difference between the rotational speed of 7 and the rotational speed of the flywheel 12, and the magnetic drag does not occur.

Next, the operation of the starting device during gear shifting will be described. When the upshift is performed, the engine speed after the shift is lower than the engine speed before the shift, and when the downshift is performed, the engine speed after the shift is higher than the engine speed before the shift. When performing an upshift, first, the torque transmission member 26 and the starting clutch member 14 are released, and then the torque transmission member 26 and the shift clutch member 15 are released. Then, the shift speed of the transmission is changed, and the start clutch member 14, the shift clutch member 15 and the torque transmission member 26 are engaged again. At this time, the engagement is smoothly performed by the interaction between the permanent magnet 32 and the driven member 33.

For example, the vehicle speed is constant, the engine is rotating at 4000 rpm before shifting, and 25 rpm after shifting.
Assuming 50 revolutions, when there is no such interaction, at the time when the torque transmission member 26 and the shift clutch member 15 are engaged, that is, the engine speed before shifting (4000 revolutions per minute). Try to maintain by inertia.

During an upshift, the accelerator opening is usually small, so the engine speed drops. Further, the rotation speed of the shift clutch member 15 becomes 2550 rotations per minute after shifting. Therefore, only the torque transmission member 26 rotates at a high rotational speed,
Due to the interaction, the torque transmission member 26 has a rotational speed corresponding to the engine rotational speed, so the starting clutch member 1
4 and the speed change clutch member 15 and the torque transmission member 26 are smoothly engaged.

Similarly, when downshifting is performed,
The starting clutch member 14, the speed change clutch member 15, and the torque transmission member 26 are smoothly engaged. by the way,
The rotational speed and torque transmitted using electromagnetic induction change logarithmically, and the coupling capacity is relatively large in the low rotational speed region and relatively small in the high rotational speed region. Become.

Therefore, in this embodiment, the coupling capacity is set to be relatively small in the low rotation speed region and relatively large in the high rotation speed region. 1 is a conceptual diagram of a magnetic coupling according to the first embodiment of the present invention, FIG. 8 is a first state diagram of the magnetic coupling according to the first embodiment of the present invention, and FIG. 9 is a first state diagram of the present invention. It is a 2nd state figure of the magnetic coupling in an Example. 1A is a front view of the magnetic coupling, and FIG. 1B is a sectional view of the magnetic coupling.

In the figure, 32 is an annular permanent magnet, 33
Is an annular driven member that is disposed so as to face the permanent magnet 32. In the permanent magnet 32, different magnetic poles such as S pole, N pole, S pole, N pole, ... Are adjacent to each other as shown in the figure. The driven member 33 is made of a ferromagnetic material having a high magnetic permeability, and has an annular iron plate 85 forming a core material, and a secondary conductive member 86 fixed to a surface of the iron plate 85 facing the permanent magnet 32. .

The iron plate 85 and the secondary conductive member 86 have the same outer diameter and inner diameter, and they are fixed to each other by fixing means such as adhesion, welding, welding or the like. In addition, a slight gap is formed between the secondary conductive member 86 and the permanent magnet 32. The secondary conductive member 86 is made of a non-magnetic material having a low magnetic permeability, and is made of an annular copper plate 91 forming the first secondary conductive material and a non-magnetic material having a low magnetic permeability. The outer peripheral side has an annular copper plate 93 that constitutes a second secondary conductive material. In this case, the radial width of the copper plate 91 is set to be slightly wider than the width of the permanent magnet 32, while the radial width of the copper plate 93 is set to the copper plate 9.
It is made narrower than the width in the radial direction of 1.

Further, a plurality of fan-shaped ones may be arranged in the circumferential direction without making the first secondary conductive material and the second secondary conductive material annular. The copper plates 91 and 93 are concentrically arranged on the same plane and have dimensions such that a slight clearance CL is formed between the copper plate 91 and the copper plate 93 at room temperature. Further, the copper plate 91 is arranged at a position substantially facing the permanent magnet 32, and the copper plate 93 is arranged on the outer peripheral side of the position.

By the way, when the magnetic coupling is used in the vehicle starter, the magnitude of the torque transmitted depends on the amount of change in the magnetic flux linking the secondary conductive member 86 with the rotation of the permanent magnet 32. Along with this, the larger the amount of change, the larger it becomes. That is, the magnitude of the torque is proportional to the square of the magnetic flux density on the surface of the secondary conductive member 86. When the engine speed is low as when the engine (not shown) is in the idling state, the magnetic flux generated by the permanent magnet 32 links the copper plate 91 to generate the eddy current I ₁ .

On the other hand, a part of the magnetic flux generated by the permanent magnet 32 interlinks the copper plate 93, but the copper plate 9
Not only the radial width of 3 is narrower than the radial width of the copper plate 91, but also a clearance CL is formed between the copper plate 91 and the copper plate 91, so that a sufficient amount of eddy current does not flow through the copper plate 93.
Therefore, the eddy current generated in the entire secondary conductive member 86 becomes relatively small, and the torque that can be transmitted also becomes small accordingly.

As a result, the coupling capacity becomes smaller than the idling torque transmitted from the engine, so that engine stalling will not occur. Next, when the driver depresses the accelerator pedal to increase the engine rotation speed, the rotation speed of the permanent magnet 32 and the driven member 33 are increased.
The eddy current I ₁ generated in the copper plate 91 increases and the Joule heat generated by the eddy current I ₁ gradually increases.

Then, the copper plates 91 and 93 expand by the Joule heat, the clearance CL between the copper plates 91 and 93 disappears, and the copper plates 91 and 93 are integrated. In this case, since the gap CL is not formed, the eddy current I ₂ flows through the entire secondary conductive member 86. The eddy current I ₂ is the copper plate 9
It becomes larger than the eddy current I ₁ flowing only in ₁ , and the coupling capacity also becomes larger accordingly.

FIG. 10 is a torque transmission characteristic diagram of the magnetic coupling according to the first embodiment of the present invention. In the figure, the horizontal axis represents the rotational speed and the vertical axis represents the torque that can be transmitted by the magnetic coupling. In the figure, L4 is a torque transmission characteristic line in normal electromagnetic induction, and L5 is a torque transmission characteristic line of the magnetic coupling in the present embodiment. N _i is the idling speed,
T _i is the idling torque.

As shown by the torque transmission characteristic line L5, when the rotational speed of the permanent magnet 32 (FIG. 1) is low, the coupling capacity is smaller than that of the torque transmission characteristic line L4. On the other hand, as the rotational speed of the permanent magnet 32 increases, the coupling capacity has a value closer to the torque transfer characteristic line L4.
By the way, the engine (not shown) is in the idling state, and the rotation of the idling speed is transmitted to the permanent magnet 32. When the speed change clutch member 15 (FIG. 2) is engaged in this state, the torque T _{c is} generated by the magnetic coupling. Is transmitted. On the other hand, the idling torque T _i is transmitted from the engine in the idling state, but the torque T _c is smaller than the idling torque T _i .

Therefore, the torque T _c is not transmitted by the magnetic coupling, so that the engine is not stalled. As described above, in the magnetic coupling using electromagnetic induction, the coupling capacity can be made small in the region where the rotation speed is low, and can be made large in the region where the rotation speed is high.

Next, a second embodiment of the present invention will be described. FIG. 11 is a clutch release state diagram in the second embodiment of the present invention. In the figure, 12 is a flywheel, 14 is a starting clutch member, 15 is a speed change clutch member, 21 and 49 are friction plates, 26 is a torque transmission member, 27
Is a clutch wheel, 32 is a permanent magnet, 33 is a driven member, 35 is an intermediate pressure plate, 36 is a return spring, 3
Reference numeral 7 is a pressure plate, and 93 is a plate spring.

In this case, since the friction plate 49 is urged to the intermediate pressure plate 35 and the pressure plate 37 by the plate spring 19 (FIG. 5), the control range where the torque capacity is constant is controlled as shown in FIG. It can be wider than range A, and
The maximum value of the starting clutch load can be made larger than that of FIG. 7. Next, a third embodiment of the present invention will be described.

FIG. 12 is a conceptual diagram of a starting system in the third embodiment of the present invention. In the figure, 101 is an engine, 102 is a transmission, 10 is an input shaft, 11 is an output shaft,
14 is a starting clutch member, 15 is a shift clutch member, 3
Reference numeral 2 is a permanent magnet, and 33 is a driven member. Also, 108
Is a torque transmission member that transmits the rotation transmitted to the driven member 33 to the input shaft 10 via the speed change clutch member 15.

In this case, the first torque transmission system including the magnetic coupling, the torque transmission member 108 and the speed change clutch member 15 and the second torque transmission system including the starting clutch member 14 are arranged in parallel. Therefore, since the shift clutch member 15 is only engaged when forming the half-clutch state, the torque capacity of the shift clutch member 15 can be reduced.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of magnetic coupling according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the starting device according to the first embodiment of the present invention.

FIG. 3 is a clutch release state diagram in the first embodiment of the present invention.

FIG. 4 is a half clutch state diagram in the first embodiment of the present invention.

FIG. 5 is a clutch engagement state diagram in the first embodiment of the present invention.

FIG. 6 is a torque capacity characteristic diagram of the starting system according to the first embodiment of the present invention.

FIG. 7 is a pressing load characteristic diagram of the starting device according to the first embodiment of the present invention.

FIG. 8 is a first state diagram of the magnetic coupling according to the first embodiment of the present invention.

FIG. 9 is a second state diagram of the magnetic coupling according to the first embodiment of the present invention.

FIG. 10 is a torque transmission characteristic diagram of the magnetic coupling according to the first embodiment of the present invention.

FIG. 11 is a clutch release state diagram according to the second embodiment of the present invention.

FIG. 12 is a conceptual diagram of a starting device in a third embodiment of the present invention.

[Explanation of symbols]

 14 Starting Clutch Member 15 Shift Clutch Member 32 Permanent Magnet 33 Driven Member 85 Iron Plate 86 Secondary Conductive Member 91 Copper Plate 93 Plate Spring 101 Engine 102 Transmission

Claims (1)

[Claims] 1. A starting clutch member that is disengageably disposed with a magnetic coupling that transmits torque by a magnetic drag force and that receives rotation of an engine through the magnetic coupling and transmits it to a transmission when engaged. And a shift clutch member that is disengageably disposed and that directly receives the rotation of the engine at the time of engagement and transmits the rotation to the transmission, and the magnetic coupling has magnetic poles that are different from each other. It is composed of an annular permanent magnet formed and an annular driven member that is arranged facing the permanent magnet with a slight gap, and the driven member is an annular secondary conductive member. And a ring-shaped iron plate disposed on the back surface of the secondary conductive member, wherein the secondary conductive member includes a first secondary conductive material and a joule formed on the first secondary conductive material. By thermal expansion due to heat A starting device comprising: the first secondary conductive material and a second secondary conductive material disposed so as to be in contact with each other.