Hydraulic differential lock type differential

Abstract

The utility model belongs to the technical field of differential locks, and provides a hydraulic differential lock type differential mechanism which comprises a reducer shell. A pipeline is arranged in the reducer shell, a hydraulic oil inlet communicated with the pipeline is formed in the outer wall of the reducer shell, the piston assembly is arranged on the inner side of the cover plate assembly in a sliding mode, the cover plate assembly and the piston assembly form a sealing cavity, and the sealing cavity is communicated with the pipeline through an oil way. The right end of the piston assembly abuts against the push disc, the right end of the push disc abuts against the pressing disc, the friction plate set is arranged between the pressing disc and the differential mechanism right shell, and a gap is formed between the friction plate set and the pressing disc. The left end of the bolt is fixed to the connecting shell, a through hole matched with the bolt is formed in the pressing disc, the right end of the bolt penetrates through the through hole, and the bolt is sleeved with a return spring. According to the hydraulic differential lock type differential mechanism, the piston assembly is pushed to move rightwards through hydraulic force, the pressure is transmitted to the pushing disc and the pressing disc and finally transmitted to the friction plate set, the splined hub and the connecting shell rotate synchronously, and then synchronous rotation of the left half shaft and the right half shaft is achieved. The structure is simple, reliability is high and safety performance is good.

Description

Technical Field

[0001] The utility model belongs to the technical field of differential locks, and particularly relates to a hydraulic differential lock type differential. Background Technique

[0002] When an automobile turns, the outer wheel travels a longer distance than the inner wheel; when the automobile travels straight on an uneven road surface, the lengths of the curves traveled by the two wheels are also not equal; even if the road surface is very flat, due to manufacturing size errors of the tires, different wear degrees, different loads borne, or unequal inflation pressures, the rolling radii of each tire are actually not equal. If the two wheels are both fixed on the same rigid rotating shaft and the angular velocities of the two wheels are equal, the wheels will inevitably roll and slide at the same time. The sliding of the wheels on the road surface will not only accelerate the wear of the tires, increase the power consumption of the automobile, but also may lead to the deterioration of the steering and braking performance.

[0003] In order to ensure that the two driving wheels are in a pure rolling state, the axle must drive the two half-axles and wheels through a differential respectively, so that they can rotate at different angular velocities.

[0004] Generally, a differential mainly consists of parts such as a driven gear, a differential case, a cross shaft, planetary gears, and half-axle gears. The power of the engine enters the differential through the transmission shaft, directly drives the driven gear, and then is transmitted to the differential case and the cross shaft. Then, the planetary gears drive the left and right half-axles respectively to drive the left and right wheels to rotate. When the vehicle travels straight, the resistances received by the left and right wheels are quite the same, and the planetary gears in the differential case only revolve with the case and do not rotate by themselves. When the vehicle turns, the inner wheel will generate a greater resistance, and the different forces on the two half-axles will cause the middle planetary gear to rotate by itself, and there will be a speed difference between the two half-axles. The outer wheel rotates faster than the inner wheel, so that the vehicle can turn smoothly.

[0005] However, on muddy or icy roads, when one wheel loses traction, it is equivalent to having no resistance. The differential will transmit all the power to the wheel that has lost traction through the self-rotation of the planetary gears. The other wheel will not be driven because there is no power input. In this case, the vehicle can only stay in place and cannot get out of trouble. In this working condition, the differential plays a negative role in the normal driving of the vehicle. Therefore, some vehicles are equipped with a differential lock function. The function of the differential lock is equivalent to a forced intervention, making the differential stop working, and the left and right half-axles become rigidly connected. The side with resistance has power, so that the vehicle can be driven out of the mud and continue to move forward. Normally, the differential lock function is closed, and only when getting out of trouble is needed, the driver will turn on this function.

[0006] Most of the drive axles on the current market adopt mechanical differential locks, and the structure is as follows: Mechanical differential locks generally need to be switched in a parked state, which affects the vehicle operation efficiency. Moreover, the usage requirements are very strict. If the differential lock is engaged too early or disengaged too late, as long as the vehicle turns, it will cause rapid wear of the tires and abnormal damage to the components of the transmission system at the same time. Summary of the Invention

[0007] In view of the deficiencies of the prior art, the present invention provides a hydraulic differential lock type differential, which can solve the above problems.

[0008] To achieve the above object, the present invention adopts the following technical solutions: A hydraulic differential lock type differential includes a cover assembly, a piston assembly, a push plate, a pressure plate, a friction plate group, a differential right housing, a spline hub, bolts, a connection housing, and a reduction housing;

[0009] A pipeline is provided inside the reduction housing, and a hydraulic oil inlet communicating with the pipeline is provided on the outer wall of the reduction housing. The piston assembly is slidably disposed inside the cover assembly, and the cover assembly and the piston assembly form a sealed cavity. An oil passage is provided inside the cover assembly, and the sealed cavity is communicated with the pipeline through the oil passage;

[0010] The push plate and the pressure plate are both slidably disposed inside the reduction housing. The right end of the piston assembly abuts against the push plate, the right end of the push plate abuts against the pressure plate. The friction plate group is disposed between the pressure plate and the differential right housing, and there is a gap between the friction plate group and the pressure plate. The friction plate group includes steel sheets and friction plates. The steel sheets are fixed to the connection housing, the friction plates are fixed to the spline hub, and the spline hub is connected to the right half shaft through splines;

[0011] The left end of the bolt is fixed to the connection housing. The pressure plate is provided with a through hole adapted to the bolt. The right end of the bolt penetrates through the through hole. A return spring is sleeved on the bolt. The left end of the return spring abuts against the pressure plate, and the right end of the return spring is fixed to the bolt.

[0012] Preferably, a thrust bearing is provided between the piston assembly and the push plate.

[0013] Preferably, the thrust bearing is fixed to the push plate.

[0014] Preferably, a bleed valve communicating with the pipeline is provided on the outer wall of the reduction housing.

[0015] Preferably, the differential right housing and the connection housing are fixed by screws.

[0016] Preferably, a stepped hole is provided at the right end of the pressure plate, and the left end of the return spring abuts against the stepped hole.

[0017] Preferably, a limiting plate is fixed on the bolt, and the right end of the return spring is fixed to the limiting plate.

[0018] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0019] A hydraulic differential lock type differential provided by the present utility model pushes a piston assembly to move rightward through hydraulic pressure, transmits the pressure to a push plate and a pressure plate, and finally transmits it to a friction plate group, enabling a spline hub and a connection shell to rotate synchronously, thereby realizing synchronous rotation of the left and right half shafts. The structure is simple, highly reliable, has good safety performance, and is convenient for maintenance. The torque provided by the friction plate group can also protect the overall structure of the differential. When the torque exceeds the maximum torque provided by the friction plate group, relative rotation still occurs between the left and right half shafts of the vehicle, and other components will not fail and break due to excessive torque. Description of the Drawings

[0020] Figure 1 is a schematic side view structure diagram of a hydraulic differential lock type differential provided by an embodiment of the present utility model;

[0021] Figure 2 is a schematic cross-sectional structure diagram of a hydraulic differential lock type differential provided by an embodiment of the present utility model;

[0022] Figure 3 is a schematic partial cross-sectional structure diagram of a hydraulic differential lock type differential provided by an embodiment of the present utility model;

[0023] Figure 4 is a schematic cross-sectional structure diagram of a guide screw and its related parts of a hydraulic differential lock type differential provided by an embodiment of the present utility model.

[0024] In the drawings, the list of components represented by each reference numeral is as follows:

[0025] 1, hydraulic oil inlet; 2, air vent; 3, cover plate assembly; 4, piston assembly; 5, end face bearing; 6, push plate; 7, pressure plate; 8, return spring; 9, friction plate group; 10, right differential housing; 11, spline hub; 12, bolt; 13, connection shell; 14, reduction housing; 15, guide screw; 16, limit bead. Detailed Embodiments

[0026] The following further detailed description of the present utility model is made in conjunction with specific embodiments, so that those skilled in the art can understand the present utility model more clearly.

[0027] It should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "linkage" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrally formed structure. Those of ordinary skill in the art can understand the specific meanings of such terms in this patent according to specific circumstances.

[0028] Embodiment 1

[0029] See Figures 1-3 , this embodiment provides a hydraulic differential lock differential, which includes a cover assembly 3, a piston assembly 4, a push plate 6, a pressure plate 7, a friction plate group 9, a differential right housing 10, a spline hub 11, bolts 12, a connection housing 13, and a reduction housing 14.

[0030] A pipeline is provided inside the reduction housing 14, and a hydraulic oil inlet 1 communicating with the pipeline is provided on the outer wall of the reduction housing 14, and the hydraulic oil inlet 1 is for connecting with a hydraulic pump.

[0031] The cover assembly 3 is fixed to the reduction housing 14, the piston assembly 4 is slidably arranged inside the cover assembly 3, and the sliding direction of the piston assembly 4 is parallel to the axial direction of the right half shaft (it should be noted that those skilled in the art generally call the housing where the gear is installed the left side, and Figure 1 the half shaft therein is called the right half shaft).

[0032] A sealing cavity is formed between the cover assembly 3 and the piston assembly 4. A sealing ring can be provided on the inner wall of the cover assembly 3, and the sealing ring is located between the cover assembly 3 and the piston assembly 4 to improve the sealing performance of the sealing cavity. An oil passage is provided inside the cover assembly 3, and the sealing cavity is communicated with the pipeline through the oil passage. The hydraulic oil provided by the hydraulic pump can enter the pipeline from the hydraulic oil inlet 1, then enter the oil passage, and finally enter the sealing cavity to squeeze the piston assembly 4, so that the piston assembly 4 moves to the right, and the sealing cavity always remains sealed during the process of the piston assembly 4 moving to the right.

[0033] Both the push plate 6 and the pressure plate 7 are slidably arranged inside the reduction housing 14. The sliding directions of the push plate 6, the pressure plate 7, and the piston assembly 4 are parallel, and the right end of the piston assembly 4 abuts against the push plate 6, and the right end of the push plate 6 abuts against the pressure plate 7. The friction plate group 9 is arranged between the pressure plate 7 and the differential right housing 10, and there is a gap between the right end of the pressure plate 7 and the left end of the friction plate group 9, and the right end of the friction plate group 9 abuts against the left end of the differential right housing 10. The differential right housing 10 is fixed to the connection housing 13 by screws.

[0034] The friction plate group 9 includes steel sheets and friction plates, the steel sheets and the friction plates are arranged alternately, and there is a gap between the steel sheets and the friction plates without affecting each other. The steel sheets are fixed to the connection housing 13, the friction plates are fixed to the spline hub 11, and the spline hub 11 is connected to the right half shaft through splines.

[0035] The left end of the bolt 12 is fixed to the connecting shell 13. The pressure plate 7 is provided with a through hole adapted to the bolt 12. The right end of the bolt 12 penetrates through the through hole, and the pressure plate 7 can rotate synchronously with the connecting shell 13. A return spring 8 is sleeved on the bolt 12. The left end of the return spring 8 abuts against the pressure plate 7, and the right end of the return spring 8 is fixed to the bolt 12. When the pressure plate 7 moves to the right, the return spring 8 will be compressed.

[0036] Based on the above structure, when one side of the vehicle's tire slips, the driver turns on the hydraulic pump switch. The hydraulic oil can enter the pipeline from the hydraulic oil inlet 1, then enter the oil circuit, and finally enter the sealing cavity to squeeze the piston assembly 4, causing the piston assembly 4 to move to the right. The piston assembly 4 transmits the pressure to the push plate 6, and at the same time, it will push the push plate 6 to move to the right. The push plate 6 transmits the pressure to the pressure plate 7, and the pressure plate 7 moves to the right. The pressure plate 7 finally transmits the pressure to the friction plate group 9. When the friction plate group 9 is pressed and tightened, a frictional force is generated between the steel sheet and the friction plate. The frictional force can keep the connecting shell 13 and the spline hub 11 relatively fixed, and the spline hub 11 is connected to the right half shaft through splines. Furthermore, it can keep the connecting shell 13 and the right half shaft rotating synchronously, enabling the differential to fail and achieving synchronous rotation of the left and right half shafts, thus enabling the vehicle to get out of trouble. The torque provided by the friction plate group 9 can also protect the overall structure of the differential. When the torque exceeds the maximum torque provided by the friction plate group 9, the left and right half shafts of the vehicle will still rotate relatively, and other components will not fail and break due to excessive torque.

[0037] After the vehicle gets out of trouble, the hydraulic pump switch is turned off. At this time, the elastic force of the return spring 8 will push the pressure plate 7 to the left, and the friction plate group 9 loosens and resets, that is, the steel sheet and the friction plate reset and separate from each other, and the differential resumes its function. At the same time, the pressure plate 7 pushes the push plate 6 and the piston assembly 4 to the left, and the piston assembly 4 squeezes the hydraulic oil in the sealing cavity out along the incoming path. The structure is simple, highly reliable, has good safety performance, and is convenient for maintenance.

[0038] In this embodiment, the friction plate group 9 can be freely combined. For example, the steel sheets and the friction plates are arranged alternately, with one friction plate provided between two adjacent steel sheets, or two friction plates provided between two adjacent steel sheets, etc. There are various combination methods.

[0039] In order to reduce the wear between the piston assembly 4 and the push plate 6, in this embodiment, a thrust bearing 5 is provided between the piston assembly 4 and the push plate 6. The thrust bearing 5 is fixed to the push plate 6. The thrust bearing 5 rotates synchronously with the push plate 6, which can effectively reduce the wear between the piston assembly 4 and the push plate 6. It can also enable the vehicle to switch the differential lock mode without stopping, which is convenient for operation and improves the operation efficiency, which cannot be achieved by conventional mechanical differential locks.

[0040] In this embodiment, a gas release nozzle 2 communicating with the pipeline is provided on the outer wall of the housing reduction 14. When there is gas in the pipeline of the hydraulic oil and the pressure is unstable, the gas release nozzle 2 can be loosened at this time, and the air inside the pipeline will overflow through the gas release nozzle 2 until the hydraulic oil at the gas release nozzle 2 overflows evenly without bubbles, indicating that the internal gas has been exhausted, and then the gas release nozzle 2 can be tightened, and the return spring 8 can be reset stably.

[0041] In this embodiment, a stepped hole may be provided at the right end of the pressure plate 7, and the stepped hole is coaxial with the through hole. The left end of the return spring 8 abuts against the step inside the stepped hole, and the stepped hole can play a certain limiting role on the return spring 8, thereby improving the stability of the return spring 8.

[0042] A limiting plate may be fixed to the right end of the bolt 12, and the right end of the return spring 8 is fixed to the limiting plate. The limiting plate can improve the connection stability between the return spring 8 and the bolt 12.

[0043] Embodiment 2

[0044] See Figure 4 , on the basis of Embodiment 1, two screw holes are provided on the side of the connecting shell 13 facing the push plate 6. Guide screws 15 are screwed into both of the two screw holes. The guide screws 15 are arranged along the axial direction of the right half shaft. A sliding hole adapted to the guide screws 15 is provided through the push plate 6, and the two guide screws 15 are respectively slidably inserted into the two sliding holes, so that the push plate 6 can slide axially along the guide screws 15.

[0045] Among them, a limiting bead 16 is provided in the screw hole, and the limiting bead 16 can be a steel ball. The setting of the limiting bead 16 can prevent the two guide screws 15 from having different screwing depths. This is because affected by the accuracy of the processed thread depth, it is inevitable that the screwing heights of the two screws are inconsistent, and even a height difference appears, which affects the spring compression amount and the return spring force. When the hydraulic differential lock works, during the rightward movement of the end face bearing, the push plate 6, and the pressure plate 7, they are not concentric with the half shaft axis, resulting in movement jamming. At the same time, the pressure on the friction plates is uneven, causing uneven wear and abnormal noise.

[0046] Specifically, during installation, the guide screw 15 is screwed into the screw hole until it abuts against the limiting bead 16, that is, the screwing is completed. This can not only ensure the same screwing depth, but also improve the installation efficiency of the guide screw 15.

[0047] In this embodiment, a spring hole may also be provided on the side of the connecting shell 13 facing the push plate 6. A return spring is provided in the spring hole. One end of the return spring is connected to the push plate 6, and the other end of the return spring is connected to the inner wall of the spring hole. When the push plate 6 moves to the right along the guide screw 15, the return spring is compressed, which helps the push plate 6 to reset.

[0048] In the present utility model, the mechanisms, components, and parts for which no specific structures are described are existing structures that already exist in the prior art and can be directly purchased from the market.

[0049] In the description of the present utility model, it should be understood that the terms "upper", "lower", "left", "right", etc. indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings. They are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, as well as a specific orientation structure and operation. Therefore, it cannot be understood as a limitation to the present utility model. In addition, "first" and "second" are only for the purpose of description and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Therefore, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality" is two or more.

[0050] The above is only a preferred implementation of the present utility model and is not used to limit the protection scope of the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A hydraulic differential lock type differential, characterized in that, It includes a cover plate assembly (3), a piston assembly (4), a push plate (6), a pressure plate (7), a friction plate group (9), a differential right housing (10), a spline hub (11), bolts (12), a connecting housing (13), and a reduction housing (14); A pipeline is provided inside the reduction housing (14), a hydraulic oil inlet (1) communicating with the pipeline is provided on the outer wall of the reduction housing (14), the piston assembly (4) is slidably arranged inside the cover plate assembly (3), the cover plate assembly (3) and the piston assembly (4) form a sealed cavity, an oil passage is provided inside the cover plate assembly (3), and the sealed cavity is communicated with the pipeline through the oil passage; The push plate (6) and the pressure plate (7) are both slidably arranged inside the reduction housing (14), the right end of the piston assembly (4) abuts against the push plate (6), the right end of the push plate (6) abuts against the pressure plate (7), the friction plate group (9) is arranged between the pressure plate (7) and the differential right housing (10), a gap is provided between the friction plate group (9) and the pressure plate (7), the friction plate group (9) includes steel sheets and friction plates, the steel sheets are fixed to the connecting housing (13), the friction plates are fixed to the spline hub (11), and the spline hub (11) is connected to the right half shaft through splines; The left end of the bolt (12) is fixed to the connecting housing (13), the pressure plate (7) is provided with a through hole adapted to the bolt (12), the right end of the bolt (12) penetrates through the through hole, a return spring (8) is sleeved on the bolt (12), the left end of the return spring (8) abuts against the pressure plate (7), and the right end of the return spring (8) is fixed to the bolt (12).

2. A hydraulic differential lock type differential according to claim 1, characterized in that, A thrust bearing (5) is provided between the piston assembly (4) and the push plate (6).

3. A hydraulic differential lock type differential according to claim 2, characterized in that, The thrust bearing (5) is fixed to the push plate (6).

4. A hydraulic differential lock type differential according to claim 1, characterized in that, A bleed valve (2) communicating with the pipeline is provided on the outer wall of the reduction housing (14).

5. A hydraulic differential lock type differential according to claim 1, characterized in that, The differential right housing (10) and the connecting housing (13) are fixed by screws.

6. A hydraulic differential lock type differential according to claim 1, characterized in that, A stepped hole is provided at the right end of the pressure plate (7), and the left end of the return spring (8) abuts against the stepped hole.

7. A hydraulic differential lock type differential according to claim 1, characterized in that, A limiting plate is fixed on the bolt (12), and the right end of the return spring (8) is fixed to the limiting plate.

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