A method and device for positioning a differential spider

Abstract

The present application relates to the technical field of cross shaft universal joint, and in particular to a positioning method and device for a differential cross shaft. One of the positioning planes and the positioning hole of the cross shaft is taken as a reference, and the cross shaft is pre-positioned in a first positioning assembly; in the pre-positioning completed state, the positioning plane is attached to the positioning seat, the positioning hole is inserted and matched with the positioning pin, and the angle between the shaft head to be machined of the cross shaft and the preset axis is less than a threshold value; based on the pre-positioning completion, the second positioning assembly is controlled to move along the preset axis towards the cross shaft, so that the shaft head to be machined is sequentially in a first abutting state and a second abutting state; based on the shaft head to be machined being in the second abutting state, the second positioning assembly is controlled to stop moving, the pressing head is then controlled to clamp the shaft body of the cross shaft in cooperation with the positioning seat, and finally the second positioning assembly is separated from the cross shaft. In this way, the problem of poor positioning accuracy caused by the difference in the trimming of the outer circumferential surface of the shaft head of the cross shaft blank is solved.

Description

Technical Field

[0001] This invention relates to the technical field of cross shaft universal joints, and more specifically, to a positioning method and apparatus for a differential cross shaft. Background Technology

[0002] The differential is a core component of an automotive transmission system. Its main function is to allow the left and right drive wheels to rotate at different speeds when the vehicle turns, thereby ensuring smooth steering and reducing tire wear and power loss. The planetary gear differential is one of the most common types of differentials, consisting of a differential housing, a cross shaft, planetary gears, and axle gears. The cross shaft is fixed to the differential housing and supports the freely rotating planetary gears. The cross shaft typically consists of a shaft body and four shaft ends extending outwards in four directions from the body. Before machining the outer surface of the cross shaft blank and drilling the center holes for the shaft ends, the cross shaft needs to be positioned on a machining tool. The accuracy of the cross shaft's positioning is a problem that urgently needs to be solved. Summary of the Invention

[0003] To address the problem of poor positioning accuracy caused by the difference in the cut edges of the outer circumferential surface of the cross shaft blank, this invention provides a positioning method and device for the differential cross shaft.

[0004] In a first aspect, the present invention provides a method for positioning a differential cross shaft, comprising:

[0005] Using one of the positioning planes and positioning holes of the cross shaft as a reference, the cross shaft is pre-positioned in a first positioning assembly; wherein, the cross shaft includes an integrally formed shaft body and four shaft heads; both end faces of the shaft body are the positioning planes; the positioning holes are located on the shaft body; the first positioning assembly includes a positioning seat, a positioning pin, and a pressure head; the positioning pin is fixedly connected to the positioning seat; in the pre-positioned state, the positioning plane is in contact with the positioning seat, the positioning hole is engaged with the positioning pin, and the angle between the shaft head to be processed and the preset axis is less than a threshold value;

[0006] Based on the pre-positioning completion, the second positioning component is controlled to move along the preset axis toward the cross shaft, so that the shaft head to be processed is in a first abutting state and a second abutting state in sequence; wherein, the second positioning component includes a first jaw and a second jaw; the first jaw has an abutting plane; the second jaw has two intersecting correction slopes; the abutting plane intersects with the correction slopes; when the shaft head is in the first abutting state, the abutting plane and one of the correction slopes simultaneously abut the shaft head; when the shaft head is in the second abutting state, the abutting plane and the two correction slopes simultaneously abut the shaft head, and the axis of the shaft head coincides with the preset axis;

[0007] Based on the fact that the shaft head to be processed is in the second abutting state, the second positioning component is controlled to stop moving;

[0008] Based on the fact that the second positioning component is in a stationary state, the pressure head is controlled to cooperate with the positioning seat to clamp the shaft body of the cross shaft;

[0009] The first positioning component clamps the shaft body, and the second positioning component is disengaged from the cross shaft.

[0010] In some embodiments, the step of controlling the second positioning component to move along the preset axis toward the cross shaft based on the pre-positioning completion, so that the shaft head to be processed is sequentially in a first abutting state and a second abutting state, includes:

[0011] Based on the pre-positioning completion, the second positioning component is controlled to move along the preset axis toward the cross shaft at a first speed until the shaft head to be processed simultaneously abuts the first guide slope of the first jaw and the second guide slope of the second jaw; the first guide slope intersects with the abutting plane; the second guide slope intersects with the correction slope;

[0012] Based on the fact that the shaft head simultaneously abuts against the first guide slope and the second guide slope, the distance between the first chuck and the second chuck is controlled to gradually increase until the shaft head is in the first abutting state;

[0013] Based on the shaft head being in the first abutting state, the distance between the first chuck and the second chuck is controlled to gradually decrease until the shaft head is in the second abutting state.

[0014] In some embodiments, the step of controlling the second positioning component to move along the preset axis toward the cross shaft based on the pre-positioning completion, so that the shaft head to be processed is sequentially in a first abutting state and a second abutting state, further includes:

[0015] Based on the fact that the shaft head simultaneously abuts against the first guide slope and the second guide slope, the moving speed of the second positioning component is controlled to gradually decrease from the first speed as the initial speed until the shaft head is in the first abutting state.

[0016] In some embodiments, based on the first positioning component clamping the shaft body, disengaging the second positioning component from the cross shaft includes:

[0017] Based on the first positioning component clamping the shaft body, the second positioning component is controlled to move away from the cross axis along the preset axis at a second speed until the second positioning component disengages from the cross axis; wherein, the second speed is less than the first speed.

[0018] In some embodiments, when the cross shaft simultaneously abuts against the first chuck and the second chuck, the abutting force of the first chuck against the shaft head is controlled to be greater than the abutting force of the second chuck against the shaft head; the first chuck is located on the side of the cross shaft away from the positioning seat.

[0019] In a second aspect, the present invention provides a positioning device for a differential cross shaft, wherein the positioning device for the differential cross shaft is applied to the positioning method for a differential cross shaft in any embodiment of the first aspect; the positioning device for the differential cross shaft includes:

[0020] A first positioning component includes a positioning seat, a positioning pin, a pressure head, and a first driving unit; the positioning pin is fixedly connected to the positioning seat; the positioning seat and the pressure head are disposed opposite to each other; the positioning pin is located on the side of the positioning seat facing the pressure head; the first driving unit drives the pressure head to move toward or away from the positioning seat;

[0021] The second positioning component includes a mounting base, a first jaw, a second jaw, and a second drive unit. The first jaw and the second jaw are slidably disposed relative to the mounting base. The sliding directions of the first jaw and the second jaw are parallel to the axis of the positioning pin. The second drive unit drives the first jaw and the second jaw to move relative to each other. The first jaw includes a first movable block with an abutment plane. The second jaw includes a second movable block with two correction slopes intersecting. The correction slopes and the abutment plane are both parallel to a preset axis. The preset axis passes between the first jaw and the second jaw and intersects perpendicularly with the axis of the positioning pin. The correction slopes intersect with the abutment plane.

[0022] In some embodiments, the first movable block has a first guide slope; the abutting plane intersects with the first guide slope; the end of the first guide slope near the first positioning component is inclined in a direction away from the preset axis; the first guide slope is an inclined plane or a conical surface;

[0023] The second movable block has a second guide slope, which intersects with the correction slope; the end of the second guide slope near the first positioning component is inclined in a direction away from the preset axis; the second guide slope is an inclined plane or a conical surface.

[0024] In some embodiments, the second drive unit includes an elastic portion, a first sliding portion, and a second sliding portion; both the first sliding portion and the second sliding portion are slidably connected to the mounting base; both the first sliding portion and the second sliding portion slide along a direction parallel to the axis of the positioning pin; the elastic portion is connected between the first sliding portion and the second sliding portion; under the action of the elastic force of the elastic portion, the first sliding portion and the second sliding portion tend to move closer to each other.

[0025] In some embodiments, the first sliding portion includes a first slider, a second slider, and a first connecting rod; the first connecting rod is connected between the first slider and the second slider; the second slider is fixedly connected to the first claw; the second sliding portion includes a third slider, a fourth slider, and a second connecting rod; the second connecting rod is connected between the third slider and the fourth slider; the fourth slider is fixedly connected to the second claw.

[0026] The first slider, the second slider, the third slider, and the fourth slider are slidably connected to the mounting base; the sliding directions of the first slider, the second slider, the third slider, and the fourth slider are all parallel to the axial direction of the positioning pin; the distance between the first connecting rod and the second connecting rod gradually decreases in the direction away from the first pawl and the second pawl;

[0027] The elastic part is connected between the first slider and the third slider; under the elastic action of the elastic part, the first slider and the third slider tend to move closer to each other.

[0028] In some embodiments, the elastic portion includes a first elastic member and a second elastic member; one end of the first elastic member is connected to the mounting base, and the other end is connected to the first slider; one end of the second elastic member is connected to the mounting base, and the other end is connected to the third slider.

[0029] The angle between the first link and the preset axis is smaller than the angle between the second link and the preset axis; or, the elastic coefficient of the first elastic element is greater than the elastic coefficient of the second elastic element.

[0030] To solve the problem of poor positioning accuracy caused by the difference in the cut edges of the outer circumferential surface of the cross shaft blank, the present invention has the following advantages:

[0031] By using the cross shaft's own positioning plane and positioning hole as the design datum for pre-positioning, rather than the blank's cut edge, the initial datum for pre-positioning is ensured to be unaffected by cut edge differences. The angle between the shaft head to be processed and the preset axis is set to be less than a threshold to avoid collisions between the second positioning component and the shaft head due to excessive initial pre-positioning deviation. A step-by-step abutment method is used, where the shaft head is partially constrained in a first abutment state and then fully constrained in a second abutment state. This allows the shaft head to gradually adjust its posture under the force of the first and second jaws, achieving precise positioning. This solves the problem of poor positioning accuracy caused by cut edge differences on the outer circumferential surface of the cross shaft blank. Attached Figure Description

[0032] Figure 1 A schematic diagram of a positioning method for a differential cross shaft according to an embodiment of the related art is shown;

[0033] Figure 2 A schematic diagram of the blank cut edge structure of a differential cross shaft according to another embodiment of the related art is shown;

[0034] Figure 3 A schematic diagram of the blank cut edge structure of a differential cross shaft according to another embodiment of the related art is shown;

[0035] Figure 4 A schematic diagram of the structure of the first positioning component is shown in an embodiment of a positioning method for a differential cross shaft;

[0036] Figure 5 It shows Figure 4 The front view of the first positioning component in the image;

[0037] Figure 6 A schematic diagram of the structure of the second positioning component is shown in an embodiment of a positioning method for a differential cross shaft;

[0038] Figure 7 A simplified schematic diagram of the first contact state of a positioning method for a differential cross shaft according to an embodiment is shown;

[0039] Figure 8 A simplified schematic diagram of the second contact state of a positioning method for a differential cross shaft according to an embodiment is shown;

[0040] Figure 9 A schematic diagram of the structure of the second positioning component is shown in an embodiment of a positioning method for a differential cross shaft;

[0041] Figure 10 A schematic diagram of the positioning device structure for a differential cross shaft according to one embodiment is shown;

[0042] Figure 11A cross-sectional view of the second positioning component of a positioning device for a differential cross shaft according to one embodiment is shown.

[0043] Figure 12 A cross-sectional view of the second positioning component of the positioning device for the differential cross shaft according to another embodiment is shown.

[0044] Figure 13 A schematic diagram of the cross shaft of one embodiment is shown.

[0045] Reference numerals: 10 First positioning component; 11 Positioning seat; 12 Positioning pin; 13 Pressure head; 20 Second positioning component; 21 Mounting seat; 22 First claw; 221 First movable block; 222 Abutting plane; 223 First guide slope; 23 Second claw; 231 Second movable block; 232 Correction slope; 233 Second guide slope; 24 Second drive unit; 241 Elastic part; 2411 First elastic element; 2412 Second elastic element; 242 First sliding part; 2421 First slider; 2422 Second slider; 2423 First connecting rod; 243 Second sliding part; 2431 Third slider; 2432 Fourth slider; 2433 Second connecting rod; 30 Cross shaft; 31 Shaft body; 32 Shaft head; 33 Positioning plane; 34 Positioning hole; 40 Positioning gauge bar. Detailed Implementation

[0046] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, and are not intended to imply any limitation on the scope of the disclosure.

[0047] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments and are not intended to limit the indicated devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0048] The differential is a core component of an automotive transmission system. The planetary gear differential is one of the most common types, comprising a differential housing, a cross shaft 30, planetary gears, and axle gears. The cross shaft 30 typically includes a shaft body 31 and four shaft ends 32 extending outwards in four directions from the shaft body 31. Before machining the outer surface of the cross shaft 30 blank and drilling the center holes for the shaft ends 32, the cross shaft 30 blank needs to be positioned on a machining tool.

[0049] like Figure 1 As shown, in related technologies, a positioning gauge 40 is typically installed on the clamping device of a machine tool, and the outer diameter of the shaft head 32 to be machined is pressed against the positioning gauge 40 to position the angle, ensuring that the shaft head 32 to be machined is parallel to the positioning gauge 40, thereby determining that the machining feed direction is consistent with the axial direction of the shaft head 32. However, this positioning method has the following problems:

[0050] like Figure 2 As shown, the lower die is a fixed die, and the upper die is a movable die. During the forging process, there will be a shift in the die closing position each time, and the amount of shift is not fixed each time. This results in differences and inconsistencies in the trimming amount of each blank shaft head 32 at the parting surface. Due to the difference in trimming amount on both sides of the same blank, when the two end faces of the shaft body 31 are used as positioning surfaces, the angle when the measuring rod in a fixed position is in contact with the outer circle of its shaft head 32 will also be inconsistent. Figure 3 As shown, this ultimately leads to uneven machining on both sides of the shaft head 32, resulting in waste. Differences in the cutting edges of different cross shaft 30 blanks and variations in manual feeding techniques can cause positioning deviations of the cross shaft 30 to be processed on the machine tool's clamping device, thereby reducing the product's machining accuracy.

[0051] Example 1:

[0052] To address the issue of poor positioning accuracy caused by the difference in the cut edges of the outer circumferential surface of the shaft head 32 of the cross shaft 30 blank, this embodiment discloses a positioning method for the differential cross shaft 30.

[0053] In this embodiment, as Figure 4 and Figure 5 As shown, the first positioning component 10 includes a positioning seat 11, a positioning pin 12, and a pressure head 13, with the positioning pin 12 fixedly connected to the positioning seat 11. Figure 13 As shown, the cross shaft 30 includes an integrally formed shaft body 31 and four shaft heads 32. Both end faces of the shaft body 31 are positioning planes 33, and positioning holes 34 are located on the shaft body 31.

[0054] Using one of the positioning planes 33 and the positioning hole 34 of the cross shaft 30 as a reference, the cross shaft 30 is pre-positioned in the first positioning assembly 10. In the pre-positioned state, the positioning plane 33 is in contact with the positioning seat 11, the positioning hole 34 is engaged with the positioning pin 12, and the angle between the shaft head 32 to be processed of the cross shaft 30 and the preset axis is less than a threshold value. The pressure head 13 can move within a certain range on the axis of the positioning seat 11, and is in a state away from the positioning seat 11 before pre-positioning.

[0055] By matching the shape and size of the locating pin 12 and the locating seat 11 with the locating hole 34, the structural characteristics of the locating hole 34 on the cross shaft 30 can be combined to pre-position the cross shaft 30 while simplifying the structural design of the first locating component 10. Using the two end faces of the shaft body 31 as locating planes 33, and the locating hole 34 on the shaft body 31 as a reference, the pre-positioning process uses the design reference of the cross shaft 30, rather than the easily fluctuating edges of the blank after machining, ensuring that the initial reference for pre-positioning is not affected by edge differences. This makes the pre-positioning reference more stable and solves the problem of poor positioning accuracy caused by edge differences on the outer circumferential surface of the shaft head 32 of the cross shaft 30 blank.

[0056] Based on the pre-positioning completion, the second positioning component 20 is controlled to move along a preset axis toward the cross shaft 30, so that the shaft head 32 to be processed is in a first contact state and a second contact state in sequence. After the above movement is completed, the shaft head 32 and the second positioning component 20 have sufficient contact range to ensure the accuracy of precise positioning. By setting the angle between the shaft head 32 to be processed and the preset axis of the cross shaft 30 to be less than a threshold, the collision between the second positioning component 20 and the shaft head 32 can be avoided when the pre-positioning deviation is large.

[0057] like Figure 6 As shown, the second positioning component 20 includes a first jaw 22 and a second jaw 23. The first jaw 22 has a first 222, and the second jaw 23 has two intersecting correction slopes 232, with the abutment plane 222 intersecting the correction slopes 232.

[0058] like Figure 7 As shown, when the shaft head 32 is in the first contact state, the contact plane 222 and one of the correction slopes 232 simultaneously contact the shaft head 32. Figure 8 As shown, when the shaft head 32 is in the second abutting state, the abutting plane 222 and the two corrective inclined planes 232 simultaneously abut against the shaft head 32, and the axis of the shaft head 32 coincides with the preset axis. Controlling the first jaw 22 and the second jaw 23 causes the shaft head 32 to change from the first abutting state to the second abutting state. It should be understood that during the transition from the first abutting state to the second abutting state, the first jaw 22 and the second jaw 23 exert a clamping force on the shaft head 32.

[0059] With the shaft head 32 to be processed in the second abutment state, the second positioning component 20 is controlled to stop moving. With the second positioning component 20 in a stationary state, the pressure head 13 is controlled to cooperate with the positioning seat 11 to clamp the shaft body 31 of the cross shaft 30. With the first positioning component 10 clamping the shaft body 31, the second positioning component 20 is disengaged from the cross shaft 30, thus completing the final positioning.

[0060] Before precise positioning begins, the shaft head 32 is offset from the preset axis, thus it can only be in the first contact state. After being corrected to the second contact state, precise positioning is achieved. The clamping timing and driving method of the first jaw 22 and the second jaw 23 are related to the distance the second positioning component 20 moves along the preset axis.

[0061] By gradually bringing the shaft head 32 into contact with the abutment plane 222 and the correction slope 232 of the second positioning component 20, the angle of the shaft head 32 is automatically adjusted using the constraint relationship of the mechanical structure until its axis coincides with the preset axis, eliminating the error of manual positioning and achieving higher positioning accuracy.

[0062] Preferably, the fixed connection between the locating pin 12 and the locating seat 11 can be configured as an integral molding. This can improve strength while avoiding the machining tolerances or assembly errors that may exist in a separate fixed connection between the locating pin 12 and the locating seat 11.

[0063] Furthermore, such as Figure 10 As shown, based on the pre-positioning completion, the second positioning component 20 is controlled to move along a preset axis toward the cross shaft 30, so that the shaft head 32 to be processed is sequentially in a first abutting state and a second abutting state, including:

[0064] Based on the pre-positioning completion, the second positioning component 20 is controlled to move along the preset axis toward the cross shaft 30 at a first speed until the shaft head 32 to be processed simultaneously abuts the first guide slope 223 of the first jaw 22 and the second guide slope 233 of the second jaw 23. Figure 6 As shown, the first guiding inclined surface 223 intersects with the abutment plane 222. Figure 9 As shown, the second guiding slope 233 and the correction slope 232 intersect.

[0065] Based on the fact that the shaft head 32 simultaneously abuts against the first guide slope 223 and the second guide slope 233, the distance between the first pawl 22 and the second pawl 23 is gradually increased until the shaft head 32 is in the first abutting state;

[0066] Based on the shaft head 32 being in the first contact state, the distance between the first pawl 22 and the second pawl 23 is gradually reduced until the shaft head 32 is in the second contact state.

[0067] By setting the shaft head 32 to abut against the first guide slope 223 and the second guide slope 233, the shaft head 32 can slide relative to the first guide slope 223 and the second guide slope 233 during the movement of the second positioning component 20 along the preset axis toward the cross shaft 30.

[0068] Furthermore, such as Figure 10As shown, based on the pre-positioning completion, the second positioning component 20 is controlled to move along a preset axis toward the cross shaft 30, so that the shaft head 32 to be processed is in the first abutting state and the second abutting state in sequence, and also includes:

[0069] Based on the fact that the shaft head 32 simultaneously abuts against the first guide slope 223 and the second guide slope 233, the moving speed of the second positioning component 20 is controlled to gradually decrease from the first speed as the initial speed until the shaft head 32 is in the first abutting state.

[0070] By gradually decreasing the moving speed of the second positioning component 20 from the initial speed of the first speed, the relative sliding speed between the shaft head 32 and the first guide slope 223 and the second guide slope 233 can be reduced, thus avoiding excessive frictional heat generation and damage to the second positioning component 20.

[0071] Furthermore, such as Figure 10 As shown, based on the first positioning component 10 clamping the shaft body 31, the second positioning component 20 is disengaged from the cross shaft 30, including:

[0072] Based on the first positioning component 10 clamping the shaft body 31, the second positioning component 20 is controlled to move away from the cross shaft 30 along the preset axis at a second speed until the second positioning component 20 disengages from the cross shaft 30; wherein, the second speed is less than the first speed.

[0073] This ensures that the speed at which the second positioning component 20 disengages from the cross shaft 30 is less than the speed at which the second positioning component 20 moves towards the cross shaft 30 along the preset axis, thus preventing the relative sliding speed between the second positioning component 20 and the shaft head 32 from being too fast during the disengagement process. This reduces frictional wear on the second positioning component 20 and prevents friction from causing the shaft head 32 to deviate.

[0074] Furthermore, such as Figure 10 As shown, when the cross shaft 30 is simultaneously abutting against the first chuck 22 and the second chuck 23, the abutting force of the first chuck 22 against the shaft head 32 is controlled to be greater than the abutting force of the second chuck 23 against the shaft head 32. The first chuck 22 is located on the side of the cross shaft 30 away from the positioning seat 11.

[0075] When the pre-positioning is complete, the positioning plane 33 is in contact with the positioning seat 11, and the positioning hole 34 is engaged with the positioning pin 12. When the pre-positioning is complete, the pressure head 13 is a certain distance from the positioning seat 11. By controlling the abutment force of the first pawl 22 on the shaft head 32 to be greater than the abutment force of the second pawl 23 on the shaft head 32, the cross shaft 30 will tend to be pressed towards the positioning seat 11, preventing the cross shaft 30 from making slight misalignment in the direction away from the positioning seat 11.

[0076] Example 2:

[0077] This embodiment discloses a positioning device for a differential cross shaft 30. In this embodiment, the positioning device for the differential cross shaft 30 is applied to any of the positioning methods for the differential cross shaft 30 in Embodiment 1.

[0078] Furthermore, such as Figure 10 As shown, the positioning device includes a first positioning component 10 and a second positioning component 20. The first positioning component 10 includes a positioning seat 11, a positioning pin 12, a pressure head 13, and a first drive unit. The positioning pin 12 is fixedly connected to the positioning seat 11, and the positioning seat 11 and the pressure head 13 are arranged opposite to each other, so that the cross shaft 30 can be pre-positioned after being placed on the positioning seat 11. The positioning pin 12 is located on the side of the positioning seat 11 facing the pressure head 13, and the first drive unit drives the pressure head 13 to move toward or away from the positioning seat 11. When the first drive unit controls the pressure head 13 to move away from the positioning seat 11, there is a certain distance between the pressure head 13 and the positioning seat 11, which allows the cross shaft 30 to be placed on the positioning seat 11, and the positioning pin 12 is inserted into the positioning hole 34. When the cross shaft 30 is accurately positioned on the positioning seat 11, the first drive unit controls the pressure head 13 to move toward the positioning seat 11, which can stably press the cross shaft 30 onto the positioning seat 11.

[0079] The second positioning component 20 includes a mounting base 21, a first jaw 22, a second jaw 23, and a second drive unit 24. The first jaw 22 and the second jaw 23 are slidably disposed relative to the mounting base 21, and their sliding directions are parallel to the axis of the positioning pin 12. The second drive unit 24 drives the first jaw 22 and the second jaw 23 to move relative to each other. This allows for precise control of the contact time between the first jaw 22 and the second jaw 23 and the cross shaft 30, as well as the magnitude of the clamping force. The first jaw 22 includes a first movable block 221 with an abutment plane 222. The second jaw 23 includes a second movable block 231 with two intersecting correction slopes 232. Both the correction slopes 232 and the abutment plane 222 are parallel to a preset axis, which passes between the first jaw 22 and the second jaw 23 and intersects perpendicularly with the axis of the positioning pin 12. The correction slope 232 intersects with the abutment plane 222. This allows the shaft head 32 of the cross shaft 30, whose angle with the preset axis is less than a threshold, to smoothly enter the position between the first jaw 22 and the second jaw 23 after the second positioning component 20 moves along the preset axis toward the cross shaft 30. Then, the second driving unit 24 drives the first jaw 22 and the second jaw 23 to move toward the preset axis, thereby allowing the shaft head 32 and the second positioning component 20 to transition from a disengaged state to a first abutment state and a second abutment state in sequence.

[0080] Furthermore, such as Figure 6As shown, the first movable block 221 has a first guide slope 223, and the abutting plane 222 intersects with the first guide slope 223. The end of the first guide slope 223 near the first positioning component 10 is inclined in a direction away from the preset axis. The first guide slope 223 is an inclined plane or a conical surface.

[0081] The second movable block 231 has a second guide slope 233, which intersects with the correction slope 232. The end of the second guide slope 233 near the first positioning component 10 is inclined away from the preset axis. The second guide slope 233 is an inclined plane or a conical surface. This allows the shaft head 32 to slide relative to the first guide slope 223 and the second guide slope 233 during the movement of the second positioning component 20 along the preset axis toward the cross shaft 30, enabling subsequent precise positioning even when the shaft head 32 deviates slightly from the preset axis.

[0082] Furthermore, such as Figure 11 As shown, the second drive unit 24 includes an elastic part 241, a first sliding part 242, and a second sliding part 243. Both the first sliding part 242 and the second sliding part 243 are slidably connected to the mounting base 21; both the first sliding part 242 and the second sliding part 243 slide in a direction parallel to the axis of the positioning pin 12; and the sliding directions of the first pawl 22 and the second pawl 23 are parallel to the axis of the positioning pin 12; the elastic part 241 connects the first sliding part 242 and the second sliding part 243; under the action of the elastic force of the elastic part 241, the first sliding part 242 and the second sliding part 243 tend to move closer to each other. The first sliding part 242 is connected to the first pawl 22, and the second sliding part 243 is connected to the second pawl 23. After entering the first contact state, the first pawl 22 and the second pawl 23, due to contact with the shaft head 32 located between them, will undergo a certain displacement in a direction away from each other, causing the elastic part 241 to have an elastic force. Due to the elastic force of the elastic part 241, the first sliding part 242 and the second sliding part 243 tend to move closer to each other, causing the first sliding part 242 and the second sliding part 243 to drive the first pawl 22 and the second pawl 23 to move closer to each other along the axis parallel to the positioning pin 12, thereby realizing the action of the first pawl 22 and the second pawl 23 on the shaft head 32 in the first contact state and the second contact state.

[0083] Furthermore, such as Figure 11As shown, the first sliding part 242 includes a first slider 2421, a second slider 2422, and a first connecting rod 2423. The first connecting rod 2423 connects the first slider 2421 and the second slider 2422; the second slider 2422 is fixedly connected to the first claw 22; the second sliding part 243 includes a third slider 2431, a fourth slider 2432, and a second connecting rod 2433; the second connecting rod 2433 connects the third slider 2431 and the fourth slider 2432; the fourth slider 2432 is fixedly connected to the second claw 23.

[0084] The first slider 2421, the second slider 2422, the third slider 2431, and the fourth slider 2432 are slidably connected to the mounting base 21. The sliding directions of the first slider 2421, the second slider 2422, the third slider 2431, and the fourth slider 2432 are all parallel to the axial direction of the positioning pin 12. The distance between the first connecting rod 2423 and the second connecting rod 2433 gradually decreases in the direction away from the first pawl 22 and the second pawl 23.

[0085] The elastic part 241 is connected between the first slider 2421 and the third slider 2431; under the elastic action of the elastic part 241, the first slider 2421 and the third slider 2431 tend to move closer to each other.

[0086] The distance between the first link 2423 and the second link 2433 gradually decreases in the direction away from the first pawl 22 and the second pawl 23. This reduces the length of the elastic part 241, thus lowering costs. Furthermore, the shorter elastic part 241 provides more controllable elastic force and a longer effective service life.

[0087] Furthermore, such as Figure 12 As shown, the elastic part 241 includes a first elastic element 2411 and a second elastic element 2412. One end of the first elastic element 2411 is connected to the mounting base 21, and the other end is connected to the first slider 2421; one end of the second elastic element 2412 is connected to the mounting base 21, and the other end is connected to the third slider 2431.

[0088] The angle between the first link 2423 and the preset axis is smaller than the angle between the second link 2433 and the preset axis; or, the elastic coefficient of the first elastic element 2411 is greater than the elastic coefficient of the second elastic element 2412. This ensures that during the precise positioning process, the elastic force of the first elastic element 2411 is always greater than the elastic force of the second elastic element 2412. Thus, through the sequential action of the first slider 2421, the first link 2423, the second slider 2422, the third slider 2431, the second link 2433, and the fourth slider 2432, the abutment force of the first chuck 22 on the shaft head 32 is ultimately greater than the abutment force of the second chuck 23 on the shaft head 32.

[0089] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes can be made in form and detail without departing from the scope of this disclosure.

Claims

1. A method for positioning a differential cross shaft, characterized in that, The positioning method of the differential cross shaft includes: Using one of the positioning planes and positioning holes of the cross shaft as a reference, the cross shaft is pre-positioned in a first positioning assembly; wherein, the cross shaft includes an integrally formed shaft body and four shaft heads; both end faces of the shaft body are the positioning planes; the positioning holes are located on the shaft body; the first positioning assembly includes a positioning seat, a positioning pin, and a pressure head; the positioning pin is fixedly connected to the positioning seat; in the pre-positioned state, the positioning plane is in contact with the positioning seat, the positioning hole is engaged with the positioning pin, and the angle between the shaft head to be processed and the preset axis is less than a threshold value; Based on the pre-positioning completion, the second positioning component is controlled to move along the preset axis toward the cross shaft, so that the shaft head to be processed is in a first abutting state and a second abutting state in sequence; wherein, the second positioning component includes a first jaw and a second jaw; the first jaw has an abutting plane; the second jaw has two intersecting correction slopes; the abutting plane intersects with the correction slopes; when the shaft head is in the first abutting state, the abutting plane and one of the correction slopes simultaneously abut the shaft head; when the shaft head is in the second abutting state, the abutting plane and the two correction slopes simultaneously abut the shaft head, and the axis of the shaft head coincides with the preset axis; Based on the fact that the shaft head to be processed is in the second abutting state, the second positioning component is controlled to stop moving; Based on the fact that the second positioning component is in a stationary state, the pressure head is controlled to cooperate with the positioning seat to clamp the shaft body of the cross shaft; The first positioning component clamps the shaft body, and the second positioning component is disengaged from the cross shaft.

2. The positioning method for a differential cross shaft according to claim 1, characterized in that, The step of controlling the second positioning component to move along the preset axis toward the cross shaft based on the pre-positioning completion, so that the shaft head to be processed is sequentially in a first abutting state and a second abutting state, includes: Based on the pre-positioning completion, the second positioning component is controlled to move along the preset axis toward the cross shaft at a first speed until the shaft head to be processed simultaneously abuts the first guide slope of the first jaw and the second guide slope of the second jaw; the first guide slope intersects with the abutting plane; the second guide slope intersects with the correction slope; Based on the fact that the shaft head simultaneously abuts against the first guide slope and the second guide slope, the distance between the first chuck and the second chuck is controlled to gradually increase until the shaft head is in the first abutting state; Based on the shaft head being in the first abutting state, the distance between the first chuck and the second chuck is controlled to gradually decrease until the shaft head is in the second abutting state.

3. The positioning method for a differential cross shaft according to claim 2, characterized in that, The step of controlling the second positioning component to move along the preset axis toward the cross shaft based on the pre-positioning completion, so that the shaft head to be processed is in a first abutting state and a second abutting state in sequence, further includes: Based on the fact that the shaft head simultaneously abuts against the first guide slope and the second guide slope, the moving speed of the second positioning component is controlled to gradually decrease from the first speed as the initial speed until the shaft head is in the first abutting state.

4. The positioning method for a differential cross shaft according to claim 3, characterized in that, Based on the first positioning component clamping the shaft body, disengaging the second positioning component from the cross shaft includes: Based on the first positioning component clamping the shaft body, the second positioning component is controlled to move away from the cross axis along the preset axis at a second speed until the second positioning component disengages from the cross axis; wherein, the second speed is less than the first speed.

5. The positioning method for a differential cross shaft according to claim 3, characterized in that, When the cross shaft is simultaneously abutting against the first chuck and the second chuck, the abutting force of the first chuck against the shaft head is controlled to be greater than the abutting force of the second chuck against the shaft head; the first chuck is located on the side of the cross shaft away from the positioning seat.

6. A positioning device for a differential cross shaft, characterized in that, The positioning device for the differential cross shaft includes: A first positioning component includes a positioning seat, a positioning pin, a pressure head, and a first driving unit; the positioning pin is fixedly connected to the positioning seat; the positioning seat and the pressure head are disposed opposite to each other; the positioning pin is located on the side of the positioning seat facing the pressure head; the first driving unit drives the pressure head to move toward or away from the positioning seat; The second positioning component includes a mounting base, a first jaw, a second jaw, and a second drive unit. The first jaw and the second jaw are slidably disposed relative to the mounting base. The sliding directions of the first jaw and the second jaw are parallel to the axis of the positioning pin. The second drive unit drives the first jaw and the second jaw to move relative to each other. The first jaw includes a first movable block with an abutment plane. The second jaw includes a second movable block with two correction slopes intersecting. The correction slopes and the abutment plane are both parallel to a preset axis. The preset axis passes between the first jaw and the second jaw and intersects perpendicularly with the axis of the positioning pin. The correction slopes intersect with the abutment plane.

7. A positioning device for a differential cross shaft according to claim 6, characterized in that, The first movable block has a first guide slope; the abutting plane intersects with the first guide slope; the end of the first guide slope near the first positioning component is inclined in a direction away from the preset axis; the first guide slope is an inclined plane or a conical surface; The second movable block has a second guide slope, which intersects with the correction slope; the end of the second guide slope near the first positioning component is inclined in a direction away from the preset axis; the second guide slope is an inclined plane or a conical surface.

8. A positioning device for a differential cross shaft according to claim 7, characterized in that, The second drive unit includes an elastic part, a first sliding part, and a second sliding part; both the first sliding part and the second sliding part are slidably connected to the mounting base; both the first sliding part and the second sliding part slide along a direction parallel to the axis of the positioning pin; the elastic part is connected between the first sliding part and the second sliding part; under the action of the elastic force of the elastic part, the first sliding part and the second sliding part tend to move closer to each other.

9. A positioning device for a differential cross shaft according to claim 8, characterized in that, The first sliding part includes a first slider, a second slider, and a first connecting rod; the first connecting rod is connected between the first slider and the second slider; the second slider is fixedly connected to the first claw; the second sliding part includes a third slider, a fourth slider, and a second connecting rod; the second connecting rod is connected between the third slider and the fourth slider; the fourth slider is fixedly connected to the second claw. The first slider, the second slider, the third slider, and the fourth slider are slidably connected to the mounting base; the sliding directions of the first slider, the second slider, the third slider, and the fourth slider are all parallel to the axial direction of the positioning pin; the distance between the first connecting rod and the second connecting rod gradually decreases in the direction away from the first pawl and the second pawl; The elastic part is connected between the first slider and the third slider; under the elastic action of the elastic part, the first slider and the third slider tend to move closer to each other.

10. A positioning device for a differential cross shaft according to claim 9, characterized in that, The elastic part includes a first elastic element and a second elastic element; one end of the first elastic element is connected to the mounting base and the other end is connected to the first slider; one end of the second elastic element is connected to the mounting base and the other end is connected to the third slider. The angle between the first link and the preset axis is smaller than the angle between the second link and the preset axis; or, the elastic coefficient of the first elastic element is greater than the elastic coefficient of the second elastic element.

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