Disconnector comprising a multi-plate clutch applied to a carrier of a speed reducer and a driving system comprising the same

Abstract

The present invention relates to a driving and disconnecting device for a vehicle. A driving unit for a vehicle according to one embodiment of the present invention includes: a reduction gear comprising a sun gear that rotates integrally with a driving shaft, a plurality of planetary gears that mesh with the sun gear, a ring gear that meshes with and is fixed to the planetary gears, and a carrier to which the plurality of planetary gears are rotatably connected; a differential gear device that distributes power of the driving shaft to a first shaft and a second shaft; and a disconnecting device that connects and disconnects rotational power between the carrier and the differential gear device.

Description

Technology Field

[0001] The present invention relates to a driving and disconnecting device for a vehicle. Background Technology

[0002] In a vehicle, the four-wheel drive system may adopt a structure in which either the front or rear wheel side is used as the constant drive system, and the other is selectively switched to the drive system or the driven system.

[0003] For example, in a vehicle, the front wheels may be a constant drive system, and the rear wheels may be structured to selectively become a drive system or switch to a driven system.

[0004] In this case, in 2-wheel drive mode, the rear wheels are switched to a driven system, and in 4-wheel drive mode, they are switched to a driving system.

[0005] Meanwhile, the drive unit of an electric vehicle generally includes a drive motor and a reduction gear. However, due to continuous demands such as the installation of a large-capacity battery to improve driving range per charge and improved fuel efficiency through weight reduction, the installation space for the reduction gear is subject to significant constraints.

[0006] Therefore, there is a need for a compact drive unit capable of switching between a driving and driven system. The problem to be solved

[0007] One embodiment of the present invention aims to solve at least one of the problems of the aforementioned prior art.

[0008] In addition, one embodiment of the present invention aims to provide a vehicle drive unit and a disconnect device having a compact structure that are coaxially connected to a drive motor. means of solving the problem

[0009] A vehicle drive unit according to one embodiment of the present invention comprises: a reduction gear including a sun gear that rotates integrally with a drive shaft, a plurality of planetary gears that mesh with the sun gear, a ring gear that meshes with and is fixed to the planetary gears, and a carrier to which the plurality of planetary gears are rotatably connected; a differential gear unit that distributes power of the drive shaft to a first shaft and a second shaft; and a disconnector unit that connects and disconnects rotational power between the carrier and the differential gear unit.

[0010] In at least one embodiment of the present invention, the carrier includes a hollow extension extending in the axial direction, the differential gear device is located inside the extension, and the disconnecter device includes a multi-plate clutch disposed between the carrier and the differential gear device inside the extension.

[0011] In at least one embodiment of the present invention, the multi-plate clutch comprises first friction plates fixed to the carrier, second friction plates fixed to the differential gear device, a piston that presses the second friction plates against the first friction plates, and a return spring that restores the piston, and the disconnecter device further comprises a ball lamp rotator rotated by an actuator, a ball lamp slider that includes a ball groove formed in a circumferential direction and moves linearly to press or release the piston of the multi-plate clutch, and a ball lamp that is interposed between the ball lamp rotator and the ball lamp slider and includes a plurality of balls that orbit circumferentially along the ball groove by the rotation of the ball lamp rotator to induce the linear movement of the ball lamp slider.

[0012] In at least one embodiment of the present invention, the apparatus further comprises a housing that accommodates the reduction gear, the differential gear device, and the disconnecter device, wherein the differential gear device comprises a rotating cage to which the second friction plates are fixed, a first pinion gear and a second pinion gear that rotate together with the rotating cage, a first side gear that meshes with the first pinion gear and the second pinion gear and rotates integrally with the first shaft, and a second side gear that meshes with the first pinion gear and the second pinion gear and rotates integrally with the second shaft, and the housing extends inwardly and supports the outer surface of a first bearing that rotates and supports the rotating cage on its inner surface, and includes an extended support portion formed on its outer surface that guides the linear movement of the ball lamp slider.

[0013] In at least one embodiment of the present invention, a second bearing is additionally included between the rotating cage and the carrier on the side opposite to the first bearing with respect to the first pinion gear and the second pinion gear.

[0014] In at least one embodiment of the present invention, a drive motor for rotating the drive shaft is additionally included, and the drive motor, the drive shaft, the carrier, the first friction plates and the second friction plates, the rotating cage, and the ball ramp rotator are arranged to rotate coaxially.

[0015] Meanwhile, a vehicle disconnector device according to one embodiment of the present invention is a vehicle disconnector device for connecting and disconnecting rotational power between a planetary gear reduction device and a differential gear device, comprising: first friction plates fixed to a carrier of the reduction device; second friction plates fixed to a rotating cage of the differential gear device; a piston that presses the second friction plates against the first friction plates; a return spring that restores the piston; and a ball lamp comprising a ball lamp rotator rotated by an actuator, a ball lamp slider that includes a ball groove formed in a circumferential direction and presses or releases the piston while moving in a linear direction, and a plurality of balls interposed between the ball lamp rotator and the ball lamp slider, which orbit in a circumferential direction along the ball groove by the rotation of the ball lamp rotator and induce the linear movement of the ball lamp slider.

[0016] In a disconnect device of at least one embodiment of the present invention, the carrier includes a hollow extension extending in the axial direction, and the first friction plates, the second friction plates, and the rotating cage are located inside the extension.

[0017] In a disconnect device of at least one embodiment of the present invention, the ball lamp slider is guided to move linearly by the outer surface of an extension support member that supports the outer surface of a first bearing that extends into the housing and rotates and supports the rotating cage on its inner surface, in a housing that accommodates the reduction gear, the differential gear device, and the disconnect device.

[0018] A disconnecter device of at least one embodiment of the present invention further comprises an actuator installed in the housing to rotate the ball lamp rotator, wherein the actuator comprises: a motor; a worm gear rotated by the motor; a worm wheel rotated by the worm gear; and a spur gear rotated integrally with the worm wheel and meshed with the ball lamp rotator. Effects of the invention

[0019] According to one embodiment of the present invention, a vehicle drive unit and its disconnector device having a compact structure that are coaxially connected to a drive motor can be obtained.

[0020] Due to its compact structure, it is suitable for drive units and disconnect devices of electric vehicles where there are many constraints on installation space. Brief explanation of the drawing

[0021] FIG. 1 is a schematic diagram of a vehicle drive unit according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of a vehicle drive unit according to one embodiment of the present invention. Figure 3 is a partial enlarged view. FIG. 4 is a drawing showing the inner surface of a ball lamp slider according to one embodiment of the present invention. FIG. 5 shows an actuator of a disconnecter device according to one embodiment of the present invention. Specific details for implementing the invention

[0022] The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated and described in the drawings. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0023] The suffixes "module" and "part" used in this specification are used merely for nominal distinction between components and should not be interpreted as presupposing that they are physically or chemically distinguished or separated, or that they can be distinguished or separated in this way.

[0024] Terms containing ordinal numbers, such as “first,” “second,” etc., may be used to describe various components, but said components are not limited by said terms. These terms may be used solely in a nominal sense to distinguish one component from another, and their sequential meaning is determined not by such nomenclature but by the context of the description.

[0025] The term “and / or” is used to include all cases of any combination of the multiple items in question. For example, “A and / or B” means including all three cases, such as “A,” “B,” and “A and B.”

[0026] When it is stated that one component is "connected" or "joined" to another component, it should be understood that while it may be directly connected or joined to that other component, there may also be other components in between.

[0027] The terms used in this application are used merely to describe specific embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as "comprising" or "having" are intended to specify the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0028] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0029] Hereinafter, the attached drawings will be briefly described, and embodiments of the present invention will be described in detail with reference to the drawings.

[0030] First, FIG. 1 is a schematic diagram of a vehicle drive unit according to one embodiment of the present invention, FIG. 2 is a cross-sectional view of a vehicle drive unit according to one embodiment of the present invention, and FIG. 3 is a partial enlarged view. In addition, FIG. 4 is a drawing showing the inner surface of a ball lamp slider according to one embodiment of the present invention, and FIG. 5 shows an actuator of a disconnecter device according to one embodiment of the present invention.

[0031] Referring to FIGS. 1 and 2, the driving unit of the present embodiment includes a planetary gear type reduction device (10), a disconnecter device (20, 30), and a differential gear device (50).

[0032] The reduction gear (10) includes a sun gear (11) formed on a drive shaft (DS) that rotates integrally with the motor shaft (MS) of a drive motor (DM), a plurality of planetary gears (12) that mesh with the sun gear (11) and are arranged to surround the sun gear (11), a ring gear (13) that meshes with the plurality of planetary gears (12), and a carrier (14) on which the plurality of planetary gears (12) are rotatably installed.

[0033] The drive shaft (DS) is formed as a hollow shaft, and the first shaft (S1), described later, is rotatably inserted into it.

[0034] Additionally, the planetary gear (12) is a compound gear and includes a first gear (121) and a second gear (122), wherein the second gear (122) has a smaller diameter than the first gear (121).

[0035] The second gear (122) of the planetary gear (12) meshes with the ring gear (13), and the ring gear (13) is fixedly connected to the housing (40).

[0036] The carrier (14) rotatably supports the planetary gears (12) on one side and includes a hollow, axially extended extension (141) on the opposite side.

[0037] The first friction plates (21a) of the multi-plate clutch (20) are fixedly installed on the inner surface of the extension (141) of the carrier (14).

[0038] And, the rotating cage (51) of the differential gear device (50) is located inside the carrier (14).

[0039] In the rotating cage (51), second friction plates (21b) are fixedly installed, which are frictionally coupled to or released from the first friction plates (21a) according to the operation of the ball lamp (30) described later.

[0040] The multi-plate clutch (20) includes a piston (22) for pressing the second friction plates (21b) against the first friction plates (21a), and a return spring (23) for restoring the pressed piston (22) is installed in the rotating cage (51).

[0041] Referring to FIG. 3, the ball lamp (30) includes a ball lamp rotator (31) that is rotated by an actuator (60) described later, and a ball (33) that moves from a first position to a second position of each of the plurality of grooves (g) of the ball lamp slider (32) according to the rotation of the ball lamp rotator (31).

[0042] Returning to Fig. 2, a first needle bearing (nb1) is interposed between the ball lamp slider (32) and the piston (22), and a second needle bearing (nb2) is interposed between the ball lamp rotator (31) and the housing (40).

[0043] FIG. 4 shows the inner surface of a ball lamp slider (32), and as shown, a plurality of grooves (g) are formed on the inner surface.

[0044] Each groove (g) accommodates a ball (33) and is formed such that the axial depth varies from one end of the circumferential direction to the other.

[0045] That is, as shown in Fig. 4, the axial depth of the groove (g) gradually decreases as it moves from position a to position b of the groove (g).

[0046] Although not shown, a groove may also be formed on the inner surface of the ball lamp rotator (31) corresponding to the groove (g) of the ball lamp slider (32).

[0047] As the ball (33) moves from position a (first position) to position b (second position) by the rotation of the ball lamp rotator (31), the ball lamp slider (32) moves in a straight line away from the ball lamp rotator (31).

[0048] And, as the piston (22) is pushed by such linear movement, the first friction plates (21a) and the second friction plates (21b) are pressed against each other.

[0049] When the ball lamp rotator (31) rotates in the opposite direction, the ball (33) moves back from position b of the groove (g) to position a, and the pressure on the piston (22) is released.

[0050] As the pressure is released, the piston (22) is restored by the return spring (23), and the clutch connection of the multi-plate clutch (20) is released.

[0051] The housing (40) accommodates the reduction gear (10), the disconnecter device (20, 30), and the differential gear device (50) internally, and the housing (40) includes an extended support member (41) that extends inwardly.

[0052] The inner surface of the extension support member (41) supports the outer surface of the first bearing (b1), thereby rotatingly supporting the rotating cage (51) supported by the inner surface of the first bearing (b1).

[0053] And, the outer surface of the extension support (41) includes a guide portion that guides the linear movement of the ball lamp slider (32).

[0054] To this end, as shown in FIG. 4, a guide projection (p) is formed on the inner circumference of the ball lamp slider (32), and a guide groove (r) into which the guide projection (p) is inserted is formed on the outer circumference of the extension support member (41). Of course, it is obvious that a guide groove (r) may be formed on the inner circumference of the ball lamp slider (32) and a guide projection (p) may be formed on the outer circumference of the extension support member (41).

[0055] The differential gear device (50) includes a first pinion gear (52) and a second pinion gear (53) that are housed inside a rotating cage (51) and rotate integrally with the rotating cage (51). The first pinion gear (52) and the second pinion gear (53) are rotatably installed in the rotating cage (51) and rotate together with the rotating cage (51) while rotating about an axis perpendicular to the axis of rotation.

[0056] And, the differential gear device (50) includes a first side gear (54) that meshes with the first pinion gear (52) and the second pinion gear (53) and rotates integrally with the first shaft (S1), and also includes a second side gear (55) that meshes with the first pinion gear (52) and the second pinion gear (53) and rotates integrally with the second shaft (S2).

[0057] The first shaft (S1) transmits rotational force to the first wheel, and the second shaft (S2) transmits rotational force to the second wheel on the opposite side.

[0058] In addition to rotational support by the first bearing (b1), the rotating cage (51) is rotationally supported through the inner surface of the second bearing (b2), which is supported by the inner surface of the carrier (14) on the opposite side relative to the first pinion gear (52).

[0059] Meanwhile, the disconnecter device (20, 30) includes an actuator (60) that rotates the ball lamp rotator (31), which will be explained below with reference to FIG. 5.

[0060] As shown in FIG. 5, the actuator (60) includes a motor (61), a worm gear (62) rotated by the motor (61), a worm wheel (63) meshed with the worm gear (62), and a spur gear (64) that rotates integrally with the worm wheel (63).

[0061] The spur gear (64) meshes with the ball lamp rotator (31) inside the housing (40).

[0062] In this embodiment, the drive motor (DM), drive shaft (DS), carrier (14), first friction plates (21a) and second friction plates (21b), first shaft (S1) and second shaft (S2), rotating cage (51), and ball lamp rotator (31) are arranged to rotate coaxially.

[0063] The drive unit of the present embodiment can, for example, be applied to the rear wheel of a vehicle in which a constant drive system is applied to the front wheel.

[0064] Thus, in 2-wheel drive mode, the ball lamp slider (32) retracts from the pressurized position, and the disconnector device (20, 30) is in a disconnected state, and in 4-wheel drive mode, the ball lamp rotator (31) rotates by the operation of the actuator (60), and accordingly, the ball lamp slider (32) moves to the pressurized position, and the multi-plate clutch (20) is switched to a frictional connection state, and the power of the drive motor (DM) is transmitted to the differential gear device (50).

[0065] In this embodiment, the multi-plate clutch (20) is operated by an actuator (60) including a worm gear (62) and a worm wheel (63) rather than by hydraulic pressure, so power consumption for maintaining the clutch operation state can be reduced. That is, if a hydraulic pump is used, the hydraulic pressure must be operated continuously, so the hydraulic pump is always driven and consumes electricity constantly, but if a worm gear actuator is applied, electricity is consumed only when operating and disengaging, which helps improve the fuel efficiency of the electric vehicle.

[0066] In addition, compared to the dog clutch method, the shock during operation is reduced by applying a wet multi-plate clutch, and by applying a worm gear actuator instead of a hydraulic operating method, the clutch slip problem that may occur due to hydraulic loss can be prevented by utilizing the worm gear self-locking function.

[0067] In addition, in a situation where the axial layout is limited due to the coaxial structure of the drive motor and reduction gear, high reduction performance and layout reduction can be simultaneously achieved by applying a multi-plate clutch and ball ramp structure instead of the conventional dog clutch method, and also by applying a compound planetary gear structure (2-stage planetary).

[0068] In addition, when released, the torque transmitted from the wheel shaft rotating by the front wheel can protect the drive motor connected to the sun gear from back EMF.

[0069] In addition, there is an advantage in achieving a compact structure by housing the multi-plate clutch and differential gear unit inside the carrier. Explanation of the symbols

[0070] 10: Reduction gear 20: Multi-plate clutch 30 : Ball lamp 40 : Housing 50: Differential gear unit 60 : Actuator

Claims

Claim 1 delete Claim 2 A drive unit for a vehicle comprising: a sun gear rotating integrally with a drive shaft, a plurality of planetary gears meshing with the sun gear, a ring gear meshing with and fixed to the planetary gears, and a carrier to which the plurality of planetary gears are rotatably connected; a differential gear device for distributing power of the drive shaft to a first shaft and a second shaft; and a disconnecter device for connecting and disconnecting rotational power between the carrier and the differential gear device, wherein the carrier includes a hollow extension extending in the axial direction, the differential gear device is located inside the extension, and the disconnecter device includes a multi-plate clutch disposed between the carrier and the differential gear device inside the extension. Claim 3 In claim 2, the multi-plate clutch comprises first friction plates fixed to the carrier, second friction plates fixed to the differential gear device, a piston that presses between the first friction plates and the second friction plates, and a return spring that restores the piston, and the disconnector device further comprises a ball lamp rotator rotated by an actuator, a ball lamp slider that includes a ball groove formed in a circumferential direction and presses or releases the piston of the multi-plate clutch while moving in a linear direction, and a ball lamp interposed between the ball lamp rotator and the ball lamp slider and comprising a plurality of balls that move circumferentially along the ball groove by the rotation of the ball lamp rotator to induce the linear movement of the ball lamp slider, a driving unit for a vehicle. Claim 4 A vehicle drive unit according to claim 3, further comprising a housing that accommodates the reduction gear, the differential gear device, and the disconnecter device, wherein the differential gear device comprises a rotating cage to which the second friction plates are fixed, a first pinion gear and a second pinion gear that rotate together with the rotating cage, a first side gear that meshes with the first pinion gear and the second pinion gear and rotates integrally with the first shaft, and a second side gear that meshes with the first pinion gear and the second pinion gear and rotates integrally with the second shaft, and wherein the housing extends inwardly and supports the outer surface of a first bearing that rotates and supports the rotating cage on its inner surface, and includes an extension support portion formed on its outer surface that guides the linear movement of the ball lamp slider. Claim 5 A vehicle drive unit according to claim 4, further comprising a second bearing interposed between the rotating cage and the carrier on the side opposite the first bearing with respect to the first pinion gear and the second pinion gear. Claim 6 A vehicle drive unit according to claim 4, further comprising a drive motor for rotating the drive shaft, wherein the drive motor, the drive shaft, the carrier, the first friction plates and the second friction plates, the rotating cage, and the ball lamp rotator are arranged to rotate coaxially. Claim 7 A vehicle disconnecter device for connecting and disconnecting rotational power between a planetary gear reduction device and a differential gear device, comprising: first friction plates fixed to a carrier of the reduction device; second friction plates fixed to a rotating cage of the differential gear device; a piston that presses the second friction plates against the first friction plates; a return spring that restores the piston; and a ball lamp comprising a ball lamp rotator rotated by an actuator, a ball lamp slider that includes a ball groove formed in a circumferential direction and moves linearly to press or release the piston, and a plurality of balls interposed between the ball lamp rotator and the ball lamp slider and orbiting in a circumferential direction along the ball groove by the rotation of the ball lamp rotator to induce the linear movement of the ball lamp slider. Claim 8 A disconnecter device for a vehicle according to claim 7, wherein the carrier includes a hollow extension extending in the axial direction, and the first friction plates, the second friction plates, and the rotating cage are located inside the extension. Claim 9 In claim 7, the ball lamp slider is a vehicle disconnecter device in which linear movement is guided by the outer surface of an extension support member that supports the outer surface of a first bearing that extends into the housing and rotatably supports the rotating cage on its inner surface, in a housing that accommodates the reduction gear, the differential gear device, and the disconnecter device. Claim 10 A disconnector device for a vehicle according to claim 9, further comprising an actuator installed in the housing to rotate the ball lamp rotator, wherein the actuator comprises: a motor; a worm gear rotated by the motor; a worm wheel rotated by the worm gear; and a spur gear rotated integrally with the worm wheel and meshed with the ball lamp rotator.

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