JPH11107718A - Rotational phase control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out stable phase control regardless of change of absolute rotational speed of input/output members while assembling a planetary gear mechanism and driving means for changing a phase with an end part of a cam shaft in a lump and compactly, in a case where the phase of the cam shaft is controlled using the planetary gear mechanism and the driving means for changing the phase. SOLUTION: A planetary gear mechanism 10 provided with a sun gear 11, a planetary carrier 12 and a ring gear 15, and a motor 20 provided with a rotor 21 provided with a permanent magnet 22 and a stator 23 provided with a stator coil, are arranged concentrically. The rotor 21 and the stator 23 are respectively connected to the sun gear 11 and the planetary carrier 12. A cam pulley 3 is connected to a carrier 13, and the cam shaft 1 is connected to the ring gear 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotational phase control device used for controlling valve timing of an engine.

[0002]

2. Description of the Related Art Conventionally, a device for controlling the rotational phase of an output member with respect to an input member has been used, for example, for controlling valve timing of an engine. In this case, rotation is transmitted via a transmission means by a crankshaft. In a valve operating mechanism in which an intake valve and an exhaust valve are opened and closed by a camshaft, a rotation phase control device is provided between an input member such as a cam pulley linked to a crankshaft and a camshaft as an output member. It has been incorporated.

[0003] Various structures of the rotation phase control device are known, and as a relatively compact and excellent controllability, for example, as disclosed in Japanese Patent Application Laid-Open No. 4-23212, a camshaft and a cam pulley are provided. In the meantime, a planetary gear mechanism supported by a sun gear and a planet carrier and composed of a planet gear and a ring gear is provided, a cam pulley is connected to the ring gear, a cam shaft is connected to the planet carrier, and a step motor is connected to the engine body. There is known an apparatus in which a sun gear of a planetary gear mechanism is installed and connected to the step motor via a worm gear or the like.

In this device, when the sun gear is stopped, the camshaft rotates at a reduction ratio according to the design of the planetary gear mechanism with respect to the cam pulley, and the reduction ratio of the planetary gear mechanism and the distance between the crank pulley and the cam pulley. With the reduction ratio of
The phase of the camshaft changes when the camshaft rotates synchronously with the crankshaft at half the rotational speed and the sun gear is driven by a step motor.

[0005]

According to the conventional apparatus as described above, a planetary gear mechanism is incorporated at the end of the camshaft, while a step motor is installed on the engine body side, and this and the sun gear are connected to a worm gear or the like. It is necessary to connect via
An installation space for a step motor, a worm gear, and the like is required near the camshaft installation location.

The sun gear connected to the step motor stops when the step motor is not driven, and the ring gear and the planet carrier rotate according to the rotation of the crankshaft, and the sun gear driven by the step motor and the output member side. Since the relative speed of the planet carrier changes according to the engine speed, the drive torque during the phase control for driving the sun gear is greatly affected by the engine speed (the speed of the input and output members).

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention makes it possible to collectively and compactly assemble the planetary gear mechanism and the phase changing drive means connected to some of the elements to the input and output members. An object of the present invention is to provide a rotation phase control device capable of performing stable phase control regardless of a change in the absolute rotation speed of an input / output member.

[0008]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a planetary gear mechanism comprising a planetary carrier supporting a sun gear, a planetary gear and a ring gear, and is concentric with an output member. In the rotational phase control device in which the input member and the output member are connected via the planetary gear mechanism, and the phase changing drive means is connected to some elements of the planetary gear mechanism, The driving means has two members arranged concentrically with the input and output members and rotating relative to each other, one of the two members is connected to the sun gear, and the other of the two members is connected to the planetary carrier, The input member is connected to one of the three elements of the planetary gear mechanism to which the two members are connected, and the input member is connected to one of the ring gears, and the two members are connected. The elements other than hydrogen is obtained by connecting the output member.

According to this device, the planetary gear mechanism and the phase changing drive unit are collectively connected to the output member while the two members constituting the phase changing drive unit are connected to the two elements of the planetary gear mechanism. And so on. Then, except when the phase is changed, the input member, each element of the planetary gear mechanism, the two members of the phase changing drive unit and the output member all rotate integrally, and the two members of the phase change drive unit relatively rotate. When driven, the components of the planetary gear mechanism rotate relative to each other to change the phase of the output member.
In this case, the relative rotation of the two members is reduced by the planetary gear mechanism and transmitted to the output member, so that the torque of the phase change driving means required for the phase change is reduced.

In the present invention, the two members of the phase changing drive means may be connected to the sun gear and the planetary carrier, the input member may be connected to the carrier, and the output member may be connected to the ring gear. For example, the sun gear connected to the other member of the phase changing drive unit rotates relative to the carrier connected to the input member and one member of the phase changing drive unit by driving the phase changing drive unit. Then, the relative rotation is reduced and transmitted to the ring gear and the output member.

If the two members of the phase change driving means are connected to the sun gear and the ring gear, and the output member is connected to the planetary carrier, the sun gear and the sun gear are driven by the driving of the phase change driving means. When the ring gear rotates relative to each other, the relative rotation is reduced and the phase change driving means transmitted to the carrier and the output member is provided with a member in which a field coil is arranged and a member in which a permanent magnet is arranged. Are configured to be concentrically rotatable relative to each other, and the two members are relatively rotated by energizing the coil during driving, and the relative rotation of the two members is prevented by the magnetic force of the permanent magnet when driving is stopped. Is preferably provided.

Thus, the phase of the output member with respect to the input member is changed by driving the motor. In addition, when the drive of the motor is stopped except when the phase is changed,
The phase of the output member with respect to the input member is kept constant by the holding force of the permanent magnet.

Further, when the motor is configured as the phase changing drive means as described above, by changing the energization state of the field coil, a rotational force is applied so as to relatively rotate the two members. The coil can be switched between a motor state and a holding force applying state in which the coil has a function as an electromagnet to provide a holding force for preventing the two members from rotating relative to each other. In addition to the coil, an electromagnet that provides a holding force for preventing the relative rotation of the two members when the driving of the phase change driving unit is stopped may be provided.

Thus, when the phase is not changed, the holding force due to the function of the electromagnet is given in addition to the holding force due to the permanent magnet, and the holding force due to the permanent magnet can be reduced. If the holding force by the permanent magnet is reduced, it is possible to reduce the current required to release the holding force when the phase is changed by driving the motor.

A switching means for short-circuiting both ends of the coil is provided in an energizing circuit for the field coil, and when the driving of the phase changing driving means is stopped, the switching means is short-circuited to thereby prevent relative rotation of the two members. Even if an induced electromotive force that gives a reverse torque is generated, the holding force by the permanent magnet can be reduced.

Further, as the phase change driving means, the above-mentioned 2
A brushless DC motor is constituted by using the members, and a rotation angle sensor is provided on the input member or a portion for driving the input member and the output member, and the brushless DC motor is energized based on the outputs of the rotation angle sensors. In this case, the relative rotation angles of the two members of the motor are checked by using the rotation angle sensors on the input side and the output side necessary for the phase control, and the current is supplied to the field coil accordingly. Current control can be performed.

Alternatively, a brushless DC motor is constituted by using the two members as a phase changing drive means, and the two members can be relatively rotated within a range of less than one rotation. If a potentiometer is built in and the rotational phase of the output member with respect to the input member is determined by the calculating means based on the output of the potentiometer, not only the output of the potentiometer is used for control for driving the motor, but also It can also be used to control the phase of the output member.

[0018] As the phase changing drive means, a vane type hydraulic drive means in which the two members rotate relative to each other in accordance with a change in oil pressure in a hydraulic chamber formed between the two members may be provided. In this case, the phase of the output member can be changed by deceleration by the planetary gear mechanism even in an operation state in which the hydraulic pressure supplied from the oil pump or the like is low and the torque of the hydraulic drive means is relatively small. It is.

Further, according to the present invention, the output member is a camshaft for operating a valve of an engine, and the input member is connected to the crankshaft via a transmission means. This is effectively applied to a configuration in which the valve opening / closing timing can be changed by changing the rotation phase of the camshaft.

In this case, the output member is a camshaft for driving the intake valve, and the planetary gear mechanism or the phase changing driving means is provided with a stopper for restricting the relative rotatable range of the output side with respect to the input side to a predetermined rotation angle. A mechanism is provided so that when the holding force is insufficient when the phase changing drive unit is stopped during operation of the engine, the rotation phase of the camshaft changes in the direction in which the intake valve is retarded within the range regulated by the stopper mechanism. It is preferable to configure.

In this way, if the holding force is insufficient when the phase change driving means is stopped during operation of the engine due to a failure or the like, the opening / closing timing of the intake valve is shifted to the retard side within a certain range, and the intake / exhaust valve is over-operated. Since the lap becomes smaller, it is more advantageous to secure combustion stability than to make the overlap excessive.

[0022]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 schematically shows one embodiment of the device of the present invention. In the example shown in this figure, the present invention is applied to a variable valve timing device incorporated in a valve operating mechanism of an engine. Reference numeral 1 denotes a cam shaft rotatably supported by an engine body (not shown). Thus, the intake valve 2 (or the exhaust valve) is opened and closed. A cam pulley 3 is located around an end of the camshaft 1, and the cam pulley 3 is connected to a crank pulley 5 provided at an end of the crankshaft 4 via a timing belt 6. In this example, the camshaft 1 corresponds to an output member, and the cam pulley 3 corresponds to an input member.

A planetary gear mechanism 10 and a motor 20 as a driving means for changing the phase are assembled together at the end of the camshaft 1 to form a rotation phase control device.

The planetary gear mechanism 10 includes a sun gear 11
And a planetary carrier 12 that supports a plurality of planetary gears 13 (hereinafter simply referred to as a carrier 12);
The sun gear 11, the carrier 12, and the ring gear 15 are concentrically rotatably arranged with each other. The motor 20 includes a rotor 21 and a stator 22 as two members that can rotate relative to each other.

One of two relatively rotatable members of the motor 20 is connected to the sun gear 11, and the other is connected to the carrier 12. For example, the rotor 21 is connected to the sun gear 11, and the stator 22 is connected to the carrier 12. Also, the planetary gear mechanism 1
0, the cam pulley 3 as an input member is connected to one of the elements to which the two members of the motor 20 are connected, for example, the carrier 12, and the motor is one of the three elements of the planetary gear mechanism 10. The camshaft 1 as an output member is connected to a ring gear 15 which is an element other than the element to which the two members 20 are connected.

The specific structure of the rotation phase control device will be specifically described with reference to FIGS. A threaded shaft body 8 is screwed to an end of the camshaft 1, and members constituting the planetary gear mechanism 10 and the motor 20 and the cam pulley 3 are assembled around the shaft body 8. The ring gear 15 has a gear 15b on the inner periphery of a relatively large-diameter cylindrical portion 15a.
A shaft portion 15d connected to the shaft member 8 via a connecting wall 15c at the center thereof, and the camshaft 1 is pinched by the shaft member 8 and the pin 16 in a state where the cylindrical shaft portion 15d is externally fitted to the shaft member 8. It is fixed to.

A sun gear 1 is provided around the cylindrical shaft portion 15d.
1, three planetary gears 13 supported by the carrier 12 are arranged so as to mesh with the sun gear 11 and the ring gear 15. Further, the cam pulley 3 is integrally connected to the outer periphery of the carrier 12,
It is located around the ring gear 15.

The motor 20 comprises a rotor 21 provided with a permanent magnet 22 and a stator 23 wound with a three-phase stator coil 24 for a field, and has a structure as a brushless DC motor. In the present embodiment, the rotor 21 and the stator 23 are arranged so as to face inward and outward in the radial direction, and the permanent magnet 22 and the stator coil 24 are arranged on the rotor 21 and the stator 23 so as to form 12 magnetic poles. ing.

The rotor 21 is integrally connected to the sun gear 11 of the planetary gear mechanism 10. The rotor 21 and the sun gear 11 are connected via a bearing 18 to the cylindrical shaft portion 1.
It is rotatably supported by 5d. On the other hand, the stator 23 is formed integrally with the carrier 12 and the cam pulley 3. In addition, a protrusion-shaped stopper 25 is provided on the end face of the rotor 21, and a notch 26 on a circular arc is provided over a predetermined range on the inner periphery of the carrier 12, and the stopper 25 protrudes into the notch 26. A stopper mechanism that regulates the relative rotatable range of the cam pulley 3 and the camshaft 1 to a predetermined rotation angle by regulating the relative rotatable range of the stator 23 and the rotor 21 by the notch 26 and the stopper 25 is provided. It is configured.

In FIG. 2, reference numeral 27 denotes an inner cover connected to the stator, reference numeral 28 denotes an outer cover fixed to an engine body (not shown), and reference numeral 29 denotes a slip ring provided on both covers 27 and 28. Electric power is supplied to the stator coil 24 via the ring 29.

In order to control the motor 20 and thereby control the rotation phase of the camshaft 1, as shown in FIG. 1, the rotation angle sensor on the input and output sides detects the rotation angle of the crankshaft 4. Crank angle sensor 31
And a cam angle sensor 3 for detecting a rotation angle of the camshaft 1
2 are provided. And these sensors 31,
The control unit 33 controls the energization of the stator coil 23 based on the rotation speed detection signal from the control unit 32.

That is, when the phase control of the camshaft 1 is performed, the crank angle sensor 31 and the cam angle sensor 32
The phase change of the cam angle with respect to the crank angle is checked based on the signal from the motor. When the synchronous motor such as the brushless DC motor is used as the phase changing drive unit, the motor 20 is driven by a stator. 23
It is necessary to check the relative rotation angle of the rotor 21 with respect to, and to control the energization of the stator coil 24 accordingly.
Therefore, in the present embodiment, the crank angle sensor 31 and the cam angle sensor 32 are also used for control for driving the motor 20, that is, the signals from the crank angle sensor 31 and the cam angle sensor 32 and the preset planetary gear Mechanism 10
, The relative rotation angle between the carrier 13 and the sun gear 11 of the planetary gear mechanism 10, that is, the relative rotation angle between the stator 23 and the rotor 21 of the motor 20, is accordingly determined. Is controlled.

According to the apparatus of the present embodiment as described above,
Except during the phase change, the cam pulley 3 and the members constituting the planetary gear mechanism 10 and the motor 20 and the camshaft 1 integrally rotate as described later in detail, so that the rotation of the cam pulley 3 is directly applied to the camshaft 1. Is transmitted.

When the phase of the camshaft 1 is changed from this state to change the valve timing, the rotor 21 is relatively rotated with respect to the stator 23 by the current supplied to the stator coil 24 by the amount corresponding to the change in the valve timing. Motor 20 is driven as described above. Along with this,
The relative rotation of the sun gear 11 with respect to the carrier 12 integral with the cam pulley 3 and the stator 23 and the relative rotation of the ring gear 15 change the rotational phase of the camshaft 1 connected to the ring gear 15.

As described above, each element of the planetary gear mechanism 10 and the two members of the motor 20 rotate integrally except when the valve timing is changed, and relatively rotate only when the valve timing is changed according to the change amount. , Stable phase control is performed irrespective of the change in.

Further, the relative rotation of the rotor 21 with respect to the stator 23, that is, the relative rotation of the sun gear 11 with respect to the carrier 12, is controlled by the ring gear 15 and the camshaft 1.
And the motor torque required for the phase change can be reduced.

Here, the speed ratio and the like of the planetary gear mechanism will be described. The relationship between the number of teeth of the sun gear and the ring gear of the planetary gear mechanism and the rotational speed of each element is as follows.

[0038]

[Number 1] _{n r + (Z s / Z} r) n s - or _{(1 + Z s / Z r} ) n c = 0, provided that _{n r + γn s = (1} + γ) n c, Z s: number of teeth of the sun gear Z _r: the number of teeth of the ring gear n _s: the rotational speed of the sun gear n _c: rotational speed of the carrier n _r: one of the three elements of revolution speed γ = Z _s / Z _r planetary gear mechanism of the ring gear fixed, the other If one is driven, the other one is driven, the rotation speed of the driving-side element is Ni, and the rotation speed of the driven-side element is No, the rotation speed of the fixed element is 0. The gear ratio (Ni / No) is obtained from the above equation. The following table shows the gear ratio when the relationship between fixed, driven, and driven is variously changed.

[0039]

[Table 1]

When examining the relationship between the drive of the motor 20 and the phase change of the output member, the planetary gear mechanism
Among the elements, the element connected to the input member (cam pulley 3) is regarded as fixed, and the other element to which one of the two members of the motor 20 is connected is the drive side, and the output member (camshaft 1) is connected. Can be considered as the driven side. In the device of the present embodiment, the carrier 12 is fixed and the sun gear 11
May be considered as the driving side, and the ring gear 15 may be considered as the driven side.
In this case, the pattern is No. 5 in the above table, and the absolute value of the gear ratio is 1 / γ. Therefore, the phase change of the driven camshaft 1 is reduced with respect to the rotation of the driven side by the motor 20, and the motor torque required to change the phase of the camshaft 1 is reduced according to the deceleration.
Then, by reducing the motor torque, power consumption can be reduced.

When the phase of the camshaft 1 is not changed, the driving of the motor 20 is stopped, and the holding force of the permanent magnet 22 provided on the rotor 21 causes the relative movement of the rotor 21 to the stator 23. By preventing the rotation, the relative rotation of the camshaft 1 with respect to the cam pulley 3 is prevented.

In this case, as shown in FIG. 5, a cam drive torque Td is applied between the stator 23 and the rotor 21 by a drive reaction force from the camshaft 1 side. It is relatively low in the speed range, but in the low speed range, the lubrication conditions of the valve train change and the spring reaction force from the valve spring acts greatly (when the rotation speed increases, the spring reaction force is reduced by the rotational inertia). For such reasons, the cam drive torque Td increases.
On the other hand, if the holding torque Th due to the magnetic force of the permanent magnet 22 is set relatively large in advance so as to exceed the driving torque Td in the entire operation range, the energization of the motor 20 is stopped even when the phase is not changed. Then, the phase of the camshaft 1 is kept constant. Therefore, the control is simplified, and the power consumption is reduced when the frequency of the phase change is low.

However, if the holding torque Th by the permanent magnet 22 is set relatively large as described above, it is necessary to release the holding torque at the time of changing the phase in which the motor 20 is driven by supplying a current to the stator coil 24. The current value becomes relatively large.

Therefore, as shown in FIG.
In a region where the driving torque Td is larger than the holding torque h1, the stator coil 24 may be energized so as to generate the holding torque Th2 as an electromagnet.

That is, when a brushless DC motor is used, the current supplied to the stator coil 24 is controlled so as to change the magnetic field according to the rotation angle of the rotor 21 with respect to the stator 23 when the motor is driven.
If a constant current is supplied to the stator coil 24 so as to function as an electromagnet corresponding to the second condition, the holding torque Th2 for maintaining the stopped state can be obtained. Therefore, in the low speed range where the cam drive torque Td is large, the permanent magnet 2
In addition to the holding torque Th1 provided by the permanent magnet 2, the holding torque Th2 as an electromagnet using the stator coil 24 is given so that the driving torque Td is exceeded.
2, the holding torque Th1 can be made relatively small, so that the current value for canceling the holding torque at the time of changing the phase can be made small.

Further, in this embodiment, the relative rotatable range of the output side with respect to the input side is restricted to a predetermined rotation angle by the stopper mechanism including the notch 26 and the stopper 25. Excessive deviation of the valve timing at the time of failure or the like can be avoided.
In particular, when applied to a valve train for the intake valve 2,
An effective fail-safe function is obtained. That is, for example, when the holding torque Th2 as the electromagnet is applied as described above, if the holding torque is insufficient due to a failure or the like, the phase of the camshaft 1 in the direction in which the opening / closing timing of the intake valve 2 is retarded due to the driving resistance. However, this reduces the overlap between the intake and exhaust valves,
As in the case where the overlap becomes excessively large, the flammability does not significantly deteriorate, and flammability that does not cause misfire or the like is secured.

The structure of the phase changing drive means and the like in the device of the present invention is not limited to the above embodiment, but can be variously changed. Hereinafter, other embodiments will be described.

The motor 20 constituting the driving means for changing the phase
In addition to the brushless DC motor, a stepping motor or the like can be used as long as it can control the relative rotation angle of the two members.

As means for providing a holding torque in addition to the holding torque by the permanent magnet 22 when the rotation of the motor 20 is stopped, an electromagnet may be provided on the stator or the rotor separately from the stator coil.

Alternatively, when a stepping motor or the like is used as the phase change driving means, as shown in FIG. 7, the coil 23 'is short-circuited in addition to the current supply transistor 35 in the electric circuit for the stator coil 23'. A transistor (switch means) 36 is provided, and when the motor is rotationally driven (when the phase is changed), the transistor 36 is connected via the transistor 35.
By supplying a current to the coil 23 'as indicated by a dashed-dotted arrow and turning off the transistor 35 and turning on the transistor 36 when the rotation of the motor is stopped, the current is supplied to the coil 23' according to the relative rotation of the rotor with respect to the stator, as indicated by the solid arrow. By generating a strong induced electromotive force, a reverse torque (holding torque) can be obtained.

Further, in the above embodiment, the rotor 21 and the stator 23 are formed in a cylindrical shape and are of a cylindrical type which faces inward and outward in the radial direction, but may be of a flat plate type as shown in FIGS. That is, in the embodiment shown in these figures, the rotor 121 and the stator 123 of the motor 120 are formed in a disk shape, are arranged so as to face each other in the axial direction, and have the permanent magnet 122 A stator coil 124 is provided, respectively.

A planetary gear mechanism 10 is mounted on the end of the camshaft 1.
And the motor 120 are assembled together concentrically and the sun gear 11 and the rotor 121 are integrally connected to each other.
2, the stator 123 and the cam pulley 3 are integrally connected, and the ring gear 15 and the camshaft 1 are fixedly connected as in the embodiment shown in FIGS. In addition, a stopper 125 is provided on the side surface of the rotor 121, and a groove 126 into which the stopper 125 protrudes is formed in an arc shape over a predetermined range on the corresponding side surface of the carrier 12, thereby forming an output side with respect to the input side. A stopper mechanism for regulating the relative rotatable range is configured.

With such a structure, the same operation as the embodiment shown in FIGS. 2 to 4 can be obtained.

In the example shown in FIG. 1, a crank angle sensor 31 and a cam angle sensor 32 are used.
The control of the rotation phase of the camshaft 1 and the control for driving the brushless DC motor are performed based on the rotation speed detection signals from the motors 1 and 32, as shown in FIGS. 11 and 12. , A potentiometer 131 is built in the motor 120, and control for driving the motor and camshaft 1 based on the output of the potentiometer 131
Can be controlled.

That is, the potentiometer 131
Is, for example, a contact portion 1 provided on a side surface of the rotor 121.
32, and a detector 133 provided on the carrier 12 integral with the stator 123 and in contact with the contact portion 132. The detector 133 detects a relative rotation angle of the rotor 121 with respect to the stator 123. The energization control for driving the motor is performed based on this. Further, since the drive amount of the motor 120 as the phase changing drive means is smaller than one rotation, the output of the potentiometer 131 and the speed ratio of the planetary gear mechanism 10 (see Table 1 above) determine The phase change can be calculated.

FIG. 13 schematically shows a configuration of a rotational phase control device according to still another embodiment, and FIG. 14 shows a specific structure thereof. Also in the embodiment shown in these figures, the planetary gear mechanism 210 and the motor 22
0 are assembled together concentrically and the planetary gear mechanism 210
Is composed of a sun gear 211, a carrier 212 supporting a planetary gear 213, and a ring gear 215, and the motor 220 has a rotor 22 having a permanent magnet 222.
1 and a stator 223 having a stator coil 224 are the same as in the embodiment shown in FIGS.

This embodiment is different from the above-described embodiment in that two members of a motor 220 are connected to a sun gear 211 and a ring gear 215, and a cam pulley 3 is connected to a ring gear 215, while the camshaft 1 is a carrier. 212.

That is, a cylindrical shaft portion 212a is integrally formed at the center of the carrier 212, and the cylindrical shaft portion 212a
The carrier 212 is attached to the shaft 8 while the
And the pin 216, the cam pulley 3, the ring gear 215, and the stator 223.
Are formed integrally with each other, and the bearing 21
7 so as to be rotatable. Further, the sun gear 211 and the rotor 221 integrated therewith are
18 rotatably supported by the cylindrical shaft portion 212a.

In this embodiment, substantially the same operation as in the above embodiment can be obtained.
Considering the relationship between the drive of No. 20 and the phase change, in this embodiment, the sun gear is driven, the ring gear is fixed, and the carrier is driven, so that the pattern of No. 1 in the above table is obtained, and the gear ratio is [1 + 1 / γ]. Therefore, the degree of deceleration is further enhanced as compared with the above-described embodiment, and the motor torque required to change the phase of the camshaft 1 is reduced.

Further, the two members of the motor are connected to the sun gear and the ring gear, and the camshaft (output member)
Cam pulley (input member) when connecting to the carrier
May be connected to the sun gear. In this case, the relationship between the driving of the motor and the phase change is the pattern of No. 2 in the above table, and the speed ratio is [1 + γ].

FIG. 15 shows still another embodiment of the phase changing drive means. In this embodiment, a vane type hydraulic motor (hydraulic drive means) 320 constitutes the phase change drive means.

That is, the hydraulic motor 320 includes a casing 323 corresponding to a stator,
23, and a rotor 321 rotatably arranged in the
The rotor 32 is provided at a plurality of locations on the inner peripheral portion of the casing 323.
1 are provided, and the rotor 321 is provided with vanes 322 located between the protruding walls 324, and hydraulic chambers 325 and 326 are formed on both sides of the vane 322 between the protruding walls 324. Have been.

The hydraulic chambers 325 and 326 are provided with a control valve 331.
Are connected to the oil pump 330 through the respective hydraulic chambers 32.
The supply and discharge of hydraulic oil to and from the hydraulic chamber 32 are controlled by a control valve 331.
The rotor 321 rotates relative to the casing 323 by supplying hydraulic oil to one of the casings 5 and 326 and discharging hydraulic fluid from the other. Even when the hydraulic motor 320 is used, the hydraulic motor 320 and the planetary gear mechanism as shown in each of the above embodiments (FIG. 15)
(Not shown in the figure), and the rotation phase of the output member is changed according to the driving of the hydraulic motor 320.

In this embodiment, the oil pump 3
Although the motor 30 is driven by the engine, the torque of the hydraulic motor 320 is reduced when the engine is rotated at a low speed or the like. However, the phase can be effectively changed by being combined with the planetary gear mechanism and being decelerated by the planetary gear mechanism. .

[0065]

According to the present invention, a planetary gear mechanism and a phase changing drive means having two members which rotate relative to each other are arranged concentrically, one of the two members is connected to a sun gear, and the other is a planetary carrier. , And the input member is connected to any of the three elements of the planetary gear mechanism to which the two members are connected, and the input member is connected to any element other than the element to which the two members are connected. Since the output member is connected, the planetary gear mechanism and the phase changing drive unit can be assembled to the output member or the like at a time, and the assembly work is simplified. Moreover, except when the phase is changed, the input member,
When each element of the planetary gear mechanism, the two members of the phase changing drive means and the output member all rotate integrally, and the two members of the phase changing drive means are driven to rotate relative to each other, the planetary gears are correspondingly driven. Since the phase of the output member can be changed by relative rotation of each element of the mechanism, stable control can be performed without being greatly affected by changes in the rotation speed of the input and output members.

In the present invention, the two members of the phase change driving means are connected to a sun gear and a planetary carrier, and the input member is connected to a carrier and the output member is connected to a ring gear, or If the two members of the driving means are connected to the sun gear and the ring gear, and the input member is connected to one of them, and the output member is connected to the planetary carrier, the two members are driven by the driving means for changing the phase. When the relative rotation is made, the relative rotation is decelerated and transmitted to the output member side, so that the driving torque of the phase change driving means required for the phase change can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a rotation phase control device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a specific structure of the rotation phase control device.

FIG. 3 is a front view of the rotation phase control device with a cover removed.

FIG. 4 is a sectional view taken along line AA in FIG. 2;

FIG. 5 is a diagram illustrating an example of a relationship between a cam driving torque and a holding torque.

FIG. 6 is a diagram showing another example of the relationship between cam driving torque and holding torque.

FIG. 7 is a circuit diagram showing another example of a means for giving a holding torque.

FIG. 8 is a sectional view showing a modified example of the structure of the motor of the rotation phase control device.

FIG. 9 is a front view of a stator of the motor shown in FIG. 8;

FIG. 10 is a front view of a rotor of the motor shown in FIG. 8;

FIG. 11 is a cross-sectional view showing a structure in which a potentiometer is incorporated in the rotation phase control device.

12 is an enlarged sectional view of a main part of the structure shown in FIG.

FIG. 13 is a schematic view of a rotation phase control device according to another embodiment.

14 is a sectional view showing a specific structure of the rotation phase control device shown in FIG.

FIG. 15 is a cross-sectional view showing another embodiment of the phase changing drive means in the rotation phase control device.

[Explanation of symbols]

 Reference Signs List 1 camshaft 2 intake valve 3 cam pulley 10, 210 planetary gear mechanism 11, 211 sun gear 12, 212 carrier 13, 213 planetary gear 15, 215 ring gear 20, 120, 220 motor 21, 121, 221 rotor 22, 122, 222 permanent magnet 23 , 123, 223 Stator 24, 124, 224 Stator coil 320 Hydraulic motor

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshihide Nishikawa 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Co., Ltd.

Claims (12)

[Claims] 1. A planetary gear mechanism comprising three elements, a planetary carrier supporting a sun gear and a planetary gear, and a ring gear, are arranged concentrically with an input / output member, and an input member and an output member are provided via the planetary gear mechanism. And the phase changing drive means is connected to some elements of the planetary gear mechanism, wherein the phase changing drive means is arranged concentrically with the input and output members and relative to each other. A rotating member, one of the two members being connected to the sun gear, the other of the two members being connected to one of the planetary carrier and the ring gear, and three elements of the planetary gear mechanism. Wherein the input member is connected to one of the elements to which the two members are connected, and the output member is connected to an element other than the element to which the two members are connected. Rotation phase control device. 2. The apparatus according to claim 1, wherein two members of said phase changing drive means are connected to said sun gear and said planetary carrier, said input member is connected to said carrier, and said output member is connected to said ring gear. The rotational phase control device according to claim 1. 3. The rotation phase control device according to claim 1, wherein two members of said phase changing drive means are connected to said sun gear and said ring gear, and said output member is connected to said planetary carrier. 4. A motor in which a member on which a field coil is arranged and a member on which a permanent magnet is arranged are concentrically and relatively rotatably provided as the phase changing driving means, and the motor is driven during the driving. 2. The electric motor according to claim 1, wherein the coil is energized to rotate the two members relative to each other, and a magnetic force of the permanent magnet provides a holding force for preventing the relative rotation of the two members when the driving is stopped. 4. The rotational phase control device according to any one of claims 3 to 3. 5. A motor state in which a rotational force is applied so as to rotate the two members relative to each other by changing an energization state of the field coil, and the two members are provided with a function as an electromagnet by rotating the two members. 5. The rotation phase control device according to claim 4, wherein the phase change driving means is configured to be switchable to a holding force applying state for applying a holding force for preventing relative rotation. 6. An electromagnet for providing a holding force for preventing relative rotation of the two members when the driving of the phase changing drive unit is stopped, separately from the field coil. 5. The rotation phase control device according to 4. 7. A switch circuit for short-circuiting both ends of a coil is provided in an energizing circuit for a coil for a field, and when the driving of the phase changing drive unit is stopped, the switch unit is short-circuited so that the relative position of the two members can be reduced. 5. The rotation phase control device according to claim 4, wherein an induced electromotive force that gives a reverse torque to rotation is generated. 8. A brushless DC motor using the two members as a phase change driving means, and a rotation angle sensor is provided on the input member or a portion for driving the input member and the output member. The rotation phase control device according to any one of claims 4 to 7, wherein energization of the brushless DC motor is controlled based on an output of the angle sensor. 9. A brushless DC motor using the two members as a phase changing drive means, and
The member can be relatively rotated within a range of less than one rotation, and a potentiometer is built in the brushless DC motor, and the rotational phase of the output member with respect to the input member can be obtained by arithmetic means based on the output of the potentiometer. The rotational phase control device according to any one of claims 4 to 7, wherein: 10. A vane-type hydraulic drive means wherein said two members rotate relative to each other in response to a change in oil pressure in a hydraulic chamber formed between said two members, as said phase change drive means. The rotational phase control device according to any one of claims 1 to 3. An output member is a camshaft for a valve train of an engine, an input member is connected to a crankshaft via a transmission means, and rotation of the camshaft with respect to the crankshaft in response to driving of the phase change driving means. The rotation phase control device according to any one of claims 1 to 10, wherein the valve opening / closing timing is changed by changing the phase. 12. An output member comprising a camshaft for driving an intake valve, and a stopper mechanism for restricting a relative rotatable range of an output side with respect to an input side to a predetermined rotation angle by the planetary gear mechanism or the phase changing drive means. The rotation phase of the camshaft changes in the direction in which the intake valve is retarded within the range regulated by the stopper mechanism when the holding force is insufficient when the phase change driving means is stopped during engine operation. The rotation phase control device according to claim 11, wherein the rotation phase control device is configured.