TWI796900B - Limited slip differential structure and locking method thereof - Google Patents

Abstract

A limited slip differential structure and a locking method thereof are provided. When a vehicle is in a status of skidding, axle idling or driving on a rugged road, according to the present invention, an outer cam is locked by actuating a locker and thus at least one mandrel is pushed by the outer cam. Then, an actuation plate is pushed by the at least one mandrel to have the actuation plate connecting with an inner cam. At this time, due to a rotational speed difference between the inner cam and a first bevel gear, the inner cam is pushed in the reverse direction by the first bevel gear, and then the actuation plate is pushed in the reverse direction for squeezing a first clutch set to lock a first drive shaft.

Description

Structure of Limited Slip Differential and Its Locking Method

The invention relates to a limited-slip differential structure and a locking method thereof.

The Limited Slip Differential (LSD) locker (locker) is mainly used when one side of the wheel slips, or when the vehicle is driving on a rough road and causes one side of the wheel to hang in the air, causing the two wheels to move in different directions. When rotating at a certain speed, the design of the mechanical clutch makes the speed of the wheels on both sides consistent.

When the speed difference between the left and right wheel shafts reaches a certain threshold, the cross shaft hooks with the bevel gears on both sides, and then pushes the respective connected actuator structures to the left and right sides, so that multiple action plates and multiple friction plates are engaged. , to achieve the same rotational speed of the left and right axles.

Differentials are usually engaged by coil springs when the friction plate and the axle system are connected. When the axle loses tractive force or hangs in the air, there is still a risk of slipping; in addition, this type of differential It can only be started when the differential speed of the two axles reaches a certain threshold. When one side of the wheel is suspended in the air on a heavy off-road path, it will slip and cannot output power.

The invention provides a limited slip differential structure (LSD Structure) and a locking method thereof.

An embodiment of the present disclosure provides a limited slip differential structure, the limited slip differential structure includes a body part and a body cover, wherein the body cover and the body part form a Accommodating space. In the accommodating space, include a fork shaft (fork shaft), a first actuator seat (first actuator seat), and a first clutch set (first clutch set), wherein an axial direction of the fork shaft One side is provided with a first bevel gear, and the first bevel gear train is connected with a first drive shaft; the first actuator seat system is arranged on an axially outer side of the first bevel gear; the first clutch group The system is arranged coaxially on the outer side of the first bevel gear. And, in the accommodating space, further include a locker, an outer cam, at least one push rod, an actuation plate (actuation plate), and an inner cam, wherein the actuation plate is arranged on the first bevel gear The axial outer side is arranged between the first clutch group and the first actuator seat; wherein the locker, the outer cam and the inner cam train are axially arranged on the first bevel gear, the The locker is arranged on one side of the outer cam, one end of the at least one push rod is arranged on the other side of the outer cam, the other end of the at least one push rod is arranged corresponding to one side of the actuating plate, and The inner cam train is arranged on the other side corresponding to the actuating plate.

Another embodiment of the present disclosure provides a limited-slip differential locking method, which is applicable to a limited-slip differential structure, and the limited-slip differential structure includes at least one locker. The limited slip differential locking method includes: when a first drive shaft and a second drive shaft have a rotational speed difference, actuating the locker to engage a rotating outer cam with the locker; when an outer cam stops Finally, one side of at least one ejector rod slides on the outer cam and is pushed by the outer cam with an axial positive force so that the at least one ejector rod axially pushes an actuating plate, and the actuating plate then pushes an inner cam The inner cam is separated from a first bevel gear; then, the first bevel gear pushes the inner cam in the opposite direction, and the inner cam pushes the actuating plate with an axial reverse force to push a first clutch group to lock the first drive shaft's The rotational speed, wherein the axial reverse force of the inner cam pushing the actuating plate is greater than the axial positive force of the outer cam pushing the at least one push rod.

In order to make the above-mentioned features of the present invention more comprehensible, the following specific embodiments are described in detail together with the accompanying drawings.

D1: the first drive shaft

D2: Second drive shaft

10: Main body

11: Body cover

20: fork shaft

211: The first bevel gear

211C: Bevel gear cam

212: second bevel gear

221: The first actuator seat

222: second actuator seat

231: The first clutch group

2311: The first friction plate

2312: The first function plate

232: Second clutch group

2321: second friction plate

2322: second function plate

31: Locker

32: Outer cam

32a: Outer cam lobe

33: Ejector

34: Action plate

35: elastic element

36: inner cam

36a: Inner cam lobe

37: Thrust bearing

38: Bearing ring

Fig. 1 is a cross-sectional view of the structure of a limited slip differential according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of at least one ejector rod and an outer cam in the structure of the limited-slip differential shown in FIG. 1 .

FIG. 3 is a schematic diagram of the first bevel gear and the inner cam in the limited-slip differential structure of FIG. 1 .

4a to 4f are schematic diagrams of a limited slip differential locking method according to an embodiment of the present invention.

This specification discloses a structure of a limited slip differential and a locking method thereof. The implementation of the present invention will be described below by means of specific examples and accompanying drawings. These embodiments are only used to illustrate the technical characteristics of the present invention, and are not intended to limit the patent scope of the present invention. Anyone with ordinary knowledge in the technical field will be able to make equivalent modifications and changes based on the disclosure of the following specification without departing from the spirit and scope of the present invention.

Fig. 1 is a cross-sectional view of the structure of a limited slip differential according to an embodiment of the present invention. Please refer to FIG. 1 , the limited slip differential structure includes a body part 10 and a body cover 11 , the body cover 11 and the body part 10 form an accommodating space. In the accommodating space, there is a fork shaft 20 , a first actuator seat 221 , and a first clutch group 231 . The axial direction of the fork shaft 20 One side of the direction is provided with a first bevel gear 211, the first bevel gear 211 is connected with a first driving shaft D1, and the first bevel gear 211 rotates synchronously with the first driving shaft D1.

In one embodiment, the other side of the axial direction of the fork shaft 20 is provided with a second bevel gear 212, the second bevel gear 212 is connected with a second drive shaft D2, the second bevel gear 212 is connected with the The second drive shaft D2 rotates synchronously.

The fork shaft 20 is, for example, a cross fork shaft, and a part of the fork shaft 20 is connected to a power source (not shown) to drive the first bevel gear 211 and the second bevel gear 212 to drive the first drive shaft. D1 and the second drive shaft D2.

In the accommodating space, the first actuator seat 221 is disposed corresponding to an axially outer side of the first bevel gear 211 . To further illustrate, the first bevel gear 211 has a gear part and a shaft part, the inner side of the first actuator seat 221 corresponds to the outer side of the gear part of the first bevel gear 211, and The outer side of the first actuator seat 221 is axially movably disposed on the inner side of the main body portion 10 .

In one embodiment, the accommodating space further includes: a second actuator seat 222 , and the second actuator seat 222 is disposed corresponding to the axially outer side of the second bevel gear 212 . To further illustrate, the second bevel gear 212 has a gear part and a shaft part, and the inner side of the second actuator seat 222 is set corresponding to the outer side of the gear part of the second bevel gear 212, and the second actuator seat 222 The outer side is arranged axially movable on the inner side of the body part 10 .

A first clutch set 231 is coaxially arranged outside the first bevel gear 211 . To further illustrate, the first clutch set 231 is disposed outside the shaft portion of the first bevel gear 211 .

In one embodiment, a second clutch set 232 is coaxially disposed outside the second bevel gear 212 . To further illustrate, the second clutch set 232 is disposed outside the shaft portion of the second bevel gear 212 .

In one embodiment, the first clutch set 231 includes a plurality of first friction plates 2311 and a plurality of first action plates 2312, and the first friction plates 2311 and the first action plates 2312 are connected in series. Alternately arranged (alternately arranged); the first friction plates 2311 are arranged on the shaft of the first bevel gear 211 , and the plurality of first action plates 2312 are arranged on the inner side of the main body 10 .

In one embodiment, the second clutch group 232 includes a plurality of second friction plates 2321 and a plurality of second action plates 2322, and the second friction plates 2321 and the second action plates 2322 are arranged alternately; The second friction plate 2321 is disposed on the shaft of the second bevel gear 212 , and the plurality of second action plates 2322 are disposed on the main body 10 .

In one embodiment, a portion of the first actuator seat 221 is disposed axially facing one of the plurality of first friction plates 2311 .

In one embodiment, a portion of the second actuator seat 222 is disposed axially facing one of the plurality of second friction plates 2321 .

In one embodiment, an actuating plate 34 is disposed on the axial outer side of the first bevel gear 211 and disposed between the first clutch set 231 and the first actuator seat 221 ; In one embodiment, a part of the first actuator seat 221 passes through the actuating plate 34 and is in contact with the first clutch group 231 in the axial direction. The actuating plate 34 is radially and axially movably arranged inside the main body 10 .

In one embodiment, the limited-slip differential structure further includes a locker 31, and the accommodating space further includes the locker 31, an outer cam 32, at least one push rod 33 and an inner cam 36; The cam 32 and the inner cam 36 are axially disposed on the first driving shaft D1 , and the locker 31 is disposed on one side of the outer cam 32 . In one embodiment, the lock 31 is a magnetic lock or a locking mechanism. In another embodiment, the locking device 31 is connected with a controller (not shown) for activating or deactivating the locking device 31 . In one embodiment, the limited slip differential structure further includes a thrust bearing (thrust bearing) 37 and a bearing ring (bearing ring) 38, the thrust bearing 37 and the bearing ring 38 are axially arranged on The first drive shaft D1 is disposed on the axial inner side of the locker 31 , and the thrust bearing 37 is disposed between the outer cam 32 and the bearing back ring 38 . The bearing support ring 38 and the locker 31 do not rotate synchronously with the first driving shaft D1.

FIG. 2 is a schematic diagram of at least one ejector rod and an outer cam in the structure of the limited-slip differential shown in FIG. 1 . Please refer to FIG. 1 and FIG. 2 , one end of the at least one push rod 33 is disposed on the other side of the outer cam 32 , and the other end of the at least one push rod 33 is disposed on one side of the actuating plate 34 . The at least one push rod 33 has an elastic structure inside, and when the at least one push rod 33 is pushed by an axial external force, the at least one push rod 33 will first be axially compressed and deformed by the elastic structure axis. In one embodiment, the at least one push rod 33 passes through the first clutch group 231 and faces an axially outer edge of one side of the actuating plate 34 . The at least one push rod 33 is axially movably disposed inside the main body portion 10 . One side of the outer cam 32 includes at least one outer cam protrusion 32 a, and the at least one outer cam protrusion 32 a is disposed facing one end of the at least one push rod 33 . In one embodiment, the at least one ejector rod 33 has two groups of ejector rods, and the two groups of ejector rods are arranged at intervals of 180 degrees.

The inner cam 36 is arranged corresponding to the other side of the actuating plate 34 . FIG. 3 is a schematic diagram of the first bevel gear and the inner cam in the limited-slip differential structure of FIG. 1 . In one embodiment, please refer to FIG. 3 , one side of the first bevel gear 211 includes a bevel gear protrusion 211C, one side of the inner cam 36 includes an inner cam protrusion 36a, and the bevel gear cam portion 211C is It is provided corresponding to the inner cam lobe 36a. In one embodiment, when the limited-slip differential structure of the present case is not activated, the bevel gear cam portion 211c and the inner cam protrusion 36a are in a combined state. When the limited-slip differential structure of the present case is activated Finally, because the first bevel gear 211 and the pushed inner cam 36 have different rotational speeds, the bevel gear cam portion 211C further pushes the inner cam protruding portion 36a away. The detailed action will be described later.

In one embodiment, an elastic element 35 is arranged on the axial outer side of the shaft portion of the first bevel gear 211, and is arranged between the inner cam 36 and the actuating plate 34; in one embodiment, the The elastic element 35 is a wave spring, used for restoring the actuating plate 34 after the actuating plate 34 is axially pushed.

Embodiments of the present disclosure further provide a limited-slip differential locking method, which is applicable to a limited-slip differential locker, such as the limited-slip differential structure of this application, and the limited-slip differential structure includes at least one locker. Please refer to the aforementioned content for the relevant content of the limited-slip differential structure, and will not repeat them here.

4a to 4f are schematic diagrams of a limited slip differential locking method according to an embodiment of the present invention. In one embodiment, the limited slip differential locking method works as follows. When there is a speed difference between the first drive shaft and the second drive shaft, start the locker to engage an outer cam in rotation with the locker (step 1); after an outer cam stops, one of the at least one push rod The side slides on the outer cam and is pushed by the outer cam with an axial positive force so that the at least one push rod axially pushes an actuating plate, and the actuating plate then pushes an inner cam to make the inner cam and a first bevel gear separation (step two); and Afterwards, the first bevel gear pushes the inner cam in the opposite direction, and the inner cam pushes the actuating plate with an axial reverse force to push a first clutch group to lock the rotation speed of the first drive shaft, wherein the inner cam The axial reverse force of the cam pushing the action plate is greater than the axial positive force of the outer cam pushing the at least one push rod (step 3).

Please refer to Fig. 4a, in the initial state, that is, when the limited-slip differential structure of the present case is not activated, the first bevel gear 211 and the inner cam 36, the elastic element 35, the The actuating plate 34 , the first friction plates 2311 in the first clutch group 231 , the at least one push rod 33 and the outer cam 32 rotate synchronously with the first driving shaft D1 . At this time, the locker 31 is fixed on the bearing ring 38 and does not rotate. When the limited-slip differential locking method is applicable to the limited-slip differential structure of this case, the operation of each step of the aforementioned limited-slip differential locking method will be described in detail below.

When in a state of slipping or wheel idling or when driving on a rough road, that is, when there is a speed difference between the first drive shaft D1 and the second drive shaft D2, the locker 31 can be activated by a controller To engage the rotating outer cam 32 with the locker 31 to stop the rotation, as shown in FIG. 4b. In one embodiment, the locker 31 is a magnetic locker. When the magnetic locker is activated, the outer cam 32 can be attracted towards the magnetic locker by magnetic force, and the rotating outer cam 32 can be fixed to stop the rotation. .

Referring to FIG. 4 c , when the outer cam 32 stops rotating, one side of the at least one push rod 33 slides on the outer cam 32 to push the actuating plate 34 . To further illustrate, when one side of the at least one push rod 33 slides on the outer cam 32 and moves to the outer cam protrusion 32a, the at least one push rod 33 is axially pushed to the actuating plate by the protrusion structure 34, so that the actuating plate 34 is engaged with the inner cam 36. In one embodiment, the actuating plate 34 compresses the elastic element 35 then pushes the inner cam 36, and a part of the actuation plate 34 is engaged with one side of the inner cam 36.

Referring to FIG. 4d, the internal cam 36 is pushed so that the rotational speed of the internal cam 36 is inconsistent with the rotational speed of the first bevel gear 211 , so that the first bevel gear 211 pushes the internal cam 36 away. In further words, the bevel gear cam portion 211C and the inner cam lobe portion 36a that are joined together in the initial state, because the rotation speeds of the two are different, the bevel gear cam portion 211C pushes away the inner cam lobe portion 36a, so that the inner cam 36 pushes the actuating plate 34 axially and in reverse.

Please refer to Fig. 4e, the reverse pushing force of the inner cam 36 is greater than the forward pushing force of the actuating plate 34, so the actuating plate 34 is reversely pushed to the plurality of first friction plates 2311, so that the plurality of first friction plates 2311 A friction plate 2311 is pressed against the plurality of first action plates 2312 . At this time, because the first bevel gear 211 rotates synchronously with the main body 10 , that is, the first bevel gear 211 itself does not rotate, and thus the rotation speed of the first driving shaft D1 can be locked.

In one embodiment, please refer to FIG. 4f, because the first bevel gear 211 rotates synchronously with the body part 10 (the first bevel gear 211 itself does not rotate), and the fork shaft 20 pushes the first actuator seat 221, make a part of the first actuator seat 221 reverse and axially push the plurality of first friction plates 2311 to strengthen the interaction between the plurality of first friction plates 2311 and the plurality of first friction plates. Extrusion of plate 2312.

In one embodiment, because the first bevel gear 211 rotates synchronously with the body part 10, that is, the first bevel gear 211 rotates with the body part 10 and does not rotate itself, and the first bevel gear 211 and the second bevel gear 212 and the fork shaft 20 contact and interlock with each other, therefore, the first bevel gear 211 drives the fork shaft 20 at the speed of the main body 10, and the fork shaft 20 then drives the second bevel gear 212, and then the second drive shaft D2 and the first The rotational speed of the drive shaft D1 is the same.

In another embodiment, because the first bevel gear 211 rotates synchronously with the body part 10 (the first bevel gear 211 itself does not rotate), and the fork shaft 20 pushes the second actuator seat 222, the first The second actuator seat 222 is arranged axially facing the plurality of second friction plates 2321. When the second actuator seat 222 is pushed by the fork shaft 20, the second actuator seat 222 is thus pushed toward One of the plurality of second friction plates 2321 makes the plurality of second friction plates 2321 and the plurality of second action plates 2322 squeeze; because the plurality of second friction plates 2321 and the plurality of The second action plates 2322 are arranged alternately, and the plurality of second action plates 2322 are arranged on the shaft of the second bevel gear 212, when the plurality of second friction plates 2321 and the plurality of second action plates When the plate 2322 is squeezed, the rotation speed of the main body 10 is consistent with the rotation speed of the second bevel gear 212 . Therefore, the second bevel gear 212 rotates synchronously with the main body 10 , so that the rotation speed of the second driving shaft D2 is the same as that of the first driving shaft D1 .

Therefore, when a vehicle is slipping or wheel shafts are idling or is driving on a rough road, the user activates the limited slip differential structure of the present invention, so that the vehicle can quickly and stably achieve the synchronous rotation of the two wheel shafts.

Although the present invention has been disclosed above with the embodiments, it is not intended to limit the present invention. Anyone skilled in this technical field can make changes and modifications to the above embodiments without departing from the spirit and scope of the present invention. Any equivalent changes and retouches accomplished by using the content disclosed in the present invention should still be covered by the scope of the appended patent application. Therefore, the protection scope of the present invention should be as listed in the scope of the patent application.

D1: the first drive shaft

D2: Second drive shaft

10: Main body

11: Body cover

20: fork shaft

21: Bevel gear

211: The first bevel gear

211C: Bevel gear cam

212: second bevel gear

22: Actuator seat

221: The first actuator seat

222: second actuator seat

231: The first clutch group

2311: The first friction plate

2312: The first function plate

232: Second clutch group

2321: second friction plate

2322: second function plate

31: Locker

32: Outer cam

33: Ejector

34: Action plate

35: elastic element

36: inner cam

37: Thrust bearing

38: Bearing ring

Claims (10)

A limited-slip differential structure, comprising: a body part; and a body cover, the body cover and the body part form an accommodating space; wherein a fork shaft is contained in the accommodating space, one of the fork shafts One side of the axial direction is provided with a first bevel gear, the first bevel gear train is connected with a first drive shaft; a first actuator seat, the first actuator seat is corresponding to the first bevel gear One is arranged axially outside; a first clutch group is coaxially arranged outside one of the first bevel gears; the accommodating space further includes: a locker, an outer cam, at least one ejector rod, an actuating plate and An inner cam; wherein the actuating plate is arranged on the axial outer side of the first bevel gear, and is arranged between the first clutch group and the first actuator seat; the outer cam and the inner cam shaft set on the first bevel gear, the locker is set on one side of the outer cam, one end of the at least one push rod is set on the other side of the outer cam, the other end of the at least one push rod It is arranged corresponding to one side of the actuating plate, and the inner cam is arranged corresponding to the other side of the actuating plate. The limited-slip differential structure as claimed in claim 1, wherein the at least one ejector rod passes through the first clutch group and is on the axially outer side corresponding to one side of the actuating plate. The limited-slip differential structure according to claim 2, wherein one surface of the outer cam includes at least one outer cam lobe, and the at least one outer cam lobe faces the at least one top One end of the rod is configured. The limited-slip differential structure as described in Claim 1, wherein the first bevel gear includes a bevel gear cam portion, and one surface of the inner cam includes an inner cam lobe, and the bevel gear cam portion corresponds to the inner cam portion Cam lobe setting. The limited-slip differential structure according to claim 1, wherein the outer side of the first bevel gear further includes an elastic element, and the elastic element is arranged between the actuating plate and the inner cam. The limited-slip differential structure according to claim 5, wherein the elastic element is a wave spring. The limited-slip differential structure as claimed in claim 1, wherein a part of the first actuator seat passes through the actuating plate and faces the first clutch group. The limited-slip differential structure according to claim 1, wherein the locker is a magnetic locker or a locking mechanism. The limited-slip differential structure as described in Claim 1, wherein the limited-slip differential further includes a thrust bearing and a bearing support ring, and the thrust bearing and the bearing support ring are arranged on the first drive shaft and arranged on one axial inner side of the locker, the thrust bearing is arranged between the outer cam and the bearing back ring. A limited-slip differential locking method, suitable for a limited-slip differential structure, the limited-slip differential structure includes: a body part; and a body cover, the body cover and the body part form an accommodating space; wherein In the accommodating space, a fork shaft is included, and a first bevel gear is arranged on one side of one axial direction of the fork shaft, and the first The bevel gear train is connected with a first drive shaft, and a second bevel gear is arranged on the other side of the fork shaft in the axial direction, and the second bevel gear train is connected with a second drive shaft; a first actuator seat , the first actuator seat is set corresponding to an axially outer side of the first bevel gear; a first clutch set is coaxially set on one of the outer sides of the first bevel gear; the accommodating space further includes: a Locker, an outer cam, at least one ejector rod, an actuating plate and an inner cam; wherein the actuating plate is arranged on the axial outer side of the first bevel gear, and is arranged on the first clutch group and the first between the actuator seats; the outer cam and the inner cam are axially arranged on the first bevel gear, the locker is arranged on one side of the outer cam, and one end of the at least one push rod is arranged on the On the other side of the outer cam, the other end of the at least one push rod is arranged corresponding to one side of the actuating plate, and the inner cam is arranged corresponding to the other side of the actuating plate; the limited-slip differential locking method includes: When the first drive shaft and the second drive shaft have a rotational speed difference, start the locker to engage the rotating outer cam with the locker; when the outer cam stops, one of the at least one push rod The side slides on the outer cam and is pushed by the outer cam with an axial positive force so that the at least one push rod axially pushes the actuating plate, and the actuating plate then pushes the inner cam to make the inner cam and a first The bevel gear is separated; then, the first bevel gear pushes the inner cam in the opposite direction, and the inner cam pushes the actuating plate with an axial reverse force to push the first clutch group to lock the rotation speed of the first drive shaft , wherein the axial reverse force of the inner cam pushing the actuating plate is greater than that of the outer cam pushing the at least one abutment The axial normal force of the rod.

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