An actuator of an automobile EMB braking system

Abstract

This utility model discloses an actuator for an automotive EMB braking system, belonging to the field of automotive braking. It includes a housing, within which a drive assembly, a transmission assembly, and a push rod assembly are housed. The push rod assembly includes a lead screw, a push rod nut, and an output push rod. The drive assembly is connected to the lead screw via the transmission assembly. The push rod nut is sleeved on the lead screw and threadedly engaged with it. The output push rod is connected to the push rod nut. An annular baffle is integrally formed on the outer circumference of the lead screw. A stop plate and a bearing are sleeved on the lead screw. The stop plate is pressed between the bearing and the annular baffle. A first stop protrusion is provided on the stop plate, and a second stop protrusion is provided on the push rod nut. When the push rod nut moves along the axial direction of the lead screw towards the stop plate, the first and second stop protrusions engage to limit the retraction of the push rod nut, thus achieving braking. This prevents overshoot and locking when the slider retracts at high speed, ensuring the actuator can operate normally.

Description

Technical Field

[0001] This utility model belongs to the field of automotive braking technology, specifically relating to an actuator of an automotive EMB braking system. Background Technology

[0002] EMB (Electromechanical Brake System) is a braking system that combines the advantages of electronic actuation and mechanical braking to achieve efficient, precise, and sensitive braking. Common EMB braking systems include an actuator and a brake caliper. The actuator drives the brake pads in the brake caliper to clamp the brake disc, thus braking the wheels.

[0003] In EMB braking systems, common actuators include a motor, a lead screw, and a slider. The motor drives the lead screw to rotate, and the slider is fitted onto the lead screw and threaded into it. When the lead screw rotates, it causes the slider to move along the axial direction of the lead screw, extending or retracting. When the slider extends or retracts, it causes the brake pads in the brake caliper to clamp or release the brake disc, thus achieving braking of the vehicle. However, when the slider retracts at high speed, it is prone to overshooting and locking due to inertia, affecting the normal operation of the actuator. Utility Model Content

[0004] To address the aforementioned problems in the existing technology, this utility model provides an actuator for an automotive EMB braking system. The technical problem to be solved by this utility model is achieved through the following technical solution: This utility model provides an actuator for an automotive EMB braking system, including a housing. The housing contains a drive assembly, a transmission assembly, and a push rod assembly. The push rod assembly includes a lead screw, a push rod nut, and an output push rod. The drive assembly is connected to the lead screw via the transmission assembly. The push rod nut is sleeved on the lead screw and threaded with it. The output push rod is connected to the push rod nut. An annular baffle is integrally formed on the outer circumference of the lead screw. A stop plate and a bearing are sleeved on the lead screw. The stop plate is pressed between the bearing and the annular baffle. A first stop protrusion is provided on the stop plate, and a second stop protrusion is provided on the push rod nut. When the push rod nut moves towards the stop plate along the axial direction of the lead screw, the first stop protrusion and the second stop protrusion engage in a limiting engagement to restrict the return of the push rod nut and achieve braking.

[0005] In one embodiment of the present invention, a positioning groove is provided on the side surface of the stop plate facing the push rod nut, an annular baffle is embedded in the positioning groove, a positioning protrusion is provided on the groove wall of the positioning groove, and a positioning groove is provided on the outer circumferential surface of the annular baffle, and the positioning protrusion and the positioning groove are engaged. The first stop protrusion is located on the side surface of the stop plate facing the push rod nut and outside the positioning groove, and the second stop protrusion is located on the side surface of the push rod nut facing the stop plate.

[0006] In one embodiment of this utility model, multiple positioning protrusions are provided, and the multiple positioning protrusions are evenly distributed along the circumference of the lead screw. Multiple positioning grooves are provided, and the multiple positioning protrusions and multiple positioning grooves correspond one-to-one.

[0007] In one embodiment of the present invention, an annular partition is provided on the inner wall of the housing, which divides the chamber inside the housing into a front chamber and a rear chamber. A lead screw is inserted into the annular partition, and the two ends of the lead screw are located in the front chamber and the rear chamber, respectively. The lead screw is also fitted with a locking nut assembly and a pressure plate. The locking nut assembly and the lead screw are threaded together. The locking nut assembly and the push rod nut are located on both sides of the annular partition. The locking nut assembly is used to press the pressure plate onto the annular partition.

[0008] In one embodiment of this utility model, a lip-shaped sealing ring is also fitted on the lead screw, and the lip-shaped sealing ring is pressed between the inner circumferential surface of the annular partition and the outer circumferential surface of the lead screw.

[0009] In one embodiment of the present invention, an annular boss is provided on the side surface of the annular partition facing the pressure plate, and a planar bearing is fitted on the outer circumferential surface of the annular boss, with the planar bearing pressed between the pressure plate and the annular partition.

[0010] In one embodiment of this utility model, the locking nut assembly includes a locking nut and a washer. The locking nut and the lead screw are threaded together, and the washer is pressed between the locking nut and the pressure plate.

[0011] In one embodiment of this utility model, a keyway is provided on the outer peripheral surface of the output push rod, and a guide key is provided in the keyway. The guide key is located between the outer peripheral surface of the push rod nut and the inner wall of the housing.

[0012] In one embodiment of this utility model, a sliding sleeve is also fitted onto the front end of the output push rod.

[0013] In one embodiment of this utility model, the drive assembly includes a drive motor, and the transmission assembly includes a first gear, a second gear, and a third gear that mesh in sequence. The diameter of the first gear is smaller than the diameter of the third gear. The first gear is connected to the drive motor, and the third gear is mounted on a lead screw.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: In the above-described scheme of this application, the actuator includes a housing, within which a drive assembly, a transmission assembly, and a push rod assembly are housed. The push rod assembly includes a lead screw, a push rod nut, and an output push rod. The drive assembly is connected to the lead screw via the transmission assembly. The push rod nut is fitted onto the lead screw and threadedly engages with it. The output push rod is connected to the push rod nut. An annular baffle is integrally formed on the outer circumference of the lead screw. A stop plate and a bearing are fitted onto the lead screw. The stop plate is pressed between the bearing and the annular baffle. A first stop protrusion is provided on the stop plate, and a second stop protrusion is provided on the push rod nut. When the push rod nut moves along the axial direction of the lead screw towards the stop plate, the first and second stop protrusions engage to limit the retraction of the push rod nut, thus achieving braking. With this structure, the drive assembly drives the lead screw to rotate via the transmission assembly. When the lead screw rotates, it can cause the push rod nut to extend or retract. When the lead screw rotates to retract the push rod nut, the first stop protrusion on the stop plate and the second stop protrusion on the push rod nut mutually limit each other, thereby using the stop plate to restrict the retraction of the push rod nut and prevent overshooting and locking during retraction, ensuring the normal operation of the actuator. Furthermore, the stop plate and lead screw in this application can be machined separately, reducing machining difficulty.

[0015] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the actuator in an embodiment of this utility model; Figure 2 This is a schematic diagram of the lead screw in an embodiment of this utility model; Figure 3 This is a schematic diagram of the stop plate in an embodiment of this utility model; Figure 4 This is a schematic diagram of the lead screw, stop plate, and push rod nut in an embodiment of this utility model.

[0017] Reference numerals: 1-Housing, 2-Power input unit, 21-Drive motor, 22-Transmission assembly, 221-Drive shaft, 222-First gear, 223-Second gear, 224-Third gear, 225-Intermediate shaft, 23-Deep groove ball bearing, 24-Angular contact bearing, 3-Push rod assembly, 31-Screw screw, 32-Push rod nut, 33-Guide cylinder liner, 34-Pressure plate, 35-Locking nut assembly, 36-Solid bearing, 37-Lip seal, 38-Bearing, 39-Stop plate, 4-Power output unit, 41-Output push rod, 42-Guide key, 43-Sliding sleeve, 44-Ball head push rod, 45-U-joint, 5-Parking unit, 51-Parking brake, 52-Spline sleeve. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0019] Please see Figures 1 to 4 This utility model provides an actuator for an automotive EMB braking system, including a housing 1. The housing 1 contains a drive assembly, a transmission assembly 22, and a push rod assembly 3. The push rod assembly 3 includes a lead screw 31, a push rod nut 32, and an output push rod 41. The drive assembly is connected to the lead screw 31 via the transmission assembly 22. The push rod nut 32 is sleeved on the lead screw 31 and threadedly engaged with it. The output push rod 41 is connected to the push rod nut 32. An annular baffle is integrally formed on the outer circumference of the lead screw 31. A stop plate 39 and a bearing 38 are sleeved on the lead screw 31. The stop plate 39 is pressed between the bearing 38 and the annular baffle. A first stop protrusion is provided on the stop plate 39, and a second stop protrusion is provided on the push rod nut 32. When the push rod nut 32 moves along the axial direction of the lead screw 31 toward the stop plate 39, the first and second stop protrusions engage to limit the retraction of the push rod nut 32, thus achieving braking.

[0020] In some embodiments of this application, the bearing 38 is a tapered roller bearing, the outer ring of the bearing 38 is mounted on the inner wall of the housing 1, and the inner ring of the bearing 38 is mounted on the lead screw 31.

[0021] In the above-mentioned scheme of this application, the actuator includes a housing 1, and the housing 1 is provided with a drive assembly, a transmission assembly 22 and a push rod assembly 3. The push rod assembly 3 includes a lead screw 31, a push rod nut 32 and an output push rod 41. The drive assembly is connected to the lead screw 31 through the transmission assembly 22. The push rod nut 32 is sleeved on the lead screw 31 and threaded with the lead screw 31. The output push rod 41 is connected to the push rod nut 32. An annular baffle is integrally formed on the outer circumference of the lead screw 31. A stop plate 39 and a bearing 38 are sleeved on the lead screw 31. The stop plate 39 is pressed between the bearing 38 and the annular baffle. A first stop protrusion is provided on the stop plate 39 and a second stop protrusion is provided on the push rod nut 32. When the push rod nut 32 moves toward the stop plate 39 along the axial direction of the lead screw 31, the first stop protrusion and the second stop protrusion are engaged to limit the retraction of the push rod nut 32 and achieve braking. With this structure, the drive assembly drives the lead screw 31 to rotate via the transmission assembly 22. When the lead screw 31 rotates, it can cause the push rod nut 32 to extend or retract. Specifically, when the lead screw 31 rotates to retract the push rod nut 32, the first stop protrusion on the stop plate 39 and the second stop protrusion on the push rod nut 32 mutually limit each other, thereby using the stop plate 39 to restrict the retraction of the push rod nut 32, preventing overshoot and locking during retraction, and ensuring the normal operation of the actuator. Furthermore, the stop plate 39 and the lead screw 31 in this application can be machined separately, reducing manufacturing difficulty.

[0022] In some embodiments of this application, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the stop plate 39 has a positioning groove on its side facing the push rod nut 32. An annular baffle is embedded in the positioning groove. The groove wall has a positioning protrusion, and the outer circumferential surface of the annular baffle has a positioning groove. The positioning protrusion and the positioning groove engage with each other. The first stop protrusion is located on the side of the stop plate 39 facing the push rod nut 32 and outside the positioning groove, while the second stop protrusion is located on the side of the push rod nut 32 facing the stop plate 39. With this structure, the engagement of the positioning protrusion and the positioning groove locks the stop plate 39 and the annular baffle together in the circumferential direction, preventing relative rotation between them, thereby fixing the stop plate 39 to the lead screw 31. Thus, when the push rod nut 32 retracts until the second stop protrusion on its end face contacts the first stop protrusion on the end face of the stop plate 39, the direct contact of the protrusion effectively restricts the further retraction of the push rod nut 32.

[0023] In some embodiments of this application, such as Figure 2 and Figure 3 As shown, multiple positioning protrusions are provided, and these protrusions are evenly distributed along the circumference of the lead screw 31. Multiple positioning grooves are also provided, with each protrusion and groove corresponding to the other. This structure, through the interlocking engagement of the multiple positioning protrusions and grooves, improves the reliability of the connection between the lead screw 31 and the stop plate 39.

[0024] In some embodiments of this application, such as Figure 1 As shown, an annular partition is provided on the inner wall of the housing 1, dividing the chamber inside the housing 1 into a front chamber and a rear chamber. A lead screw 31 is inserted into the annular partition, with its two ends located in the front and rear chambers, respectively. A locking nut assembly 35 and a pressure plate 34 are also fitted onto the lead screw 31. The locking nut assembly 35 and the lead screw 31 are threaded together. The locking nut assembly 35 and the push rod nut 32 are located on opposite sides of the annular partition. The locking nut assembly 35 is used to press the pressure plate 34 against the annular partition. With this structure, one end face of the bearing 38 presses against the annular partition. The pressure applied to the annular partition by the locking nut assembly 35 and the pressure plate 34 provides support for the stop plate 39, further preventing over-clamping and locking when the push rod nut 32 retracts.

[0025] In some embodiments of this application, such as Figure 1 As shown, housing 1 includes housing and guide cylinder liner 33, and bearing 38 is mounted on the inner wall of guide cylinder liner 33.

[0026] In some embodiments of this application, such as Figure 1As shown, a lip seal 37 is also fitted onto the lead screw 31, and the lip seal 37 is pressed between the inner circumferential surface of the annular partition and the outer circumferential surface of the lead screw 31. This structure can improve the overall sealing performance of the device.

[0027] In some embodiments of this application, an annular boss is further provided on the surface of the annular partition facing the pressure plate 34, and a planar bearing 36 is fitted on the outer circumferential surface of the annular boss, pressing the pressure plate 34 between the annular partition and the pressure plate 34. This structure, with the planar bearing 36 supporting the pressure plate 34, improves the stability of the pressure plate 34 during movement.

[0028] In some embodiments of this application, the locking nut assembly 35 includes a locking nut and a washer. The locking nut and the lead screw 31 are threaded together, and the washer is pressed between the locking nut and the pressure plate 34. This structure, by applying pressure to the pressure plate 34 through the locking nut and the washer, can further improve the overall stability of the device.

[0029] In some embodiments of this application, a keyway is provided on the outer peripheral surface of the output push rod 41, and a guide key 42 is provided in the keyway. The guide key 42 is located between the outer peripheral surface of the push rod nut 32 and the inner wall of the housing. With this structure, the output push rod 41 and the inner wall of the housing 1 are supported by the guide key 42, which can improve the stability of the output push rod 41 when sliding.

[0030] In some embodiments of this application, such as Figure 1 As shown, the end of the output push rod 41 is also connected to a ball head push rod 44 and a U-shaped connector 45, which can be connected to the brake caliper.

[0031] In some embodiments of this application, such as Figure 1 As shown, a sliding sleeve 43 is also fitted onto the front end of the output push rod 41. This structure further improves the stability of the output push rod 41 during sliding. With this structure, the output end of the output push rod 41 is supported by the sliding sleeve 43, which further improves the stability of the output push rod 41 during sliding.

[0032] In some embodiments of this application, the output push rod 41, the guide key 42, the sliding sleeve 43, the ball head push rod 44, and the U-shaped connector 45 together form the power output unit 4, and the drive assembly and the transmission assembly 22 together form the power input unit 2.

[0033] In some embodiments of this application, such as Figure 1As shown, the drive assembly includes a drive motor 21, and the transmission assembly 22 includes a first gear 222, a second gear 223, and a third gear 224 that mesh sequentially. The diameter of the first gear 222 is smaller than the diameter of the third gear 224. The first gear 222 is connected to the drive motor 21, and the third gear 224 is mounted on the lead screw 31. With this structure, the lead screw 31 can rotate at a preset speed by reducing speed through the first gear 222, the second gear 223, and the third gear 224.

[0034] In some embodiments of this application, the drive assembly further includes a deep groove ball bearing 23 and an angular contact bearing 24, and the transmission assembly 22 further includes a drive shaft 221 and an intermediate shaft 225. The drive shaft 221 is connected to the motor shaft of the drive motor 21, the intermediate shaft 225 is mounted on the housing 1, the first gear 222 is mounted on the drive shaft 221, and the second gear 223 is mounted on the intermediate shaft 225.

[0035] In some embodiments of this application, the actuator further includes a parking unit 5, which includes a parking brake 51 and a spline sleeve 52, the spline sleeve 52 being mounted on the motor shaft of the drive motor 21.

[0036] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0038] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0039] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. An actuator for an automotive EMB braking system, characterized in that, The device includes a housing, within which a drive assembly, a transmission assembly, and a push rod assembly are provided. The push rod assembly includes a lead screw, a push rod nut, and an output push rod. The drive assembly is connected to the lead screw via the transmission assembly. The push rod nut is sleeved on the lead screw and threadedly engaged with it. The output push rod is connected to the push rod nut. An annular baffle is integrally formed on the outer circumference of the lead screw. A stop plate and a bearing are sleeved on the lead screw. The stop plate is pressed between the bearing and the annular baffle. A first stop protrusion is provided on the stop plate. A second stop protrusion is provided on the push rod nut. When the push rod nut moves toward the stop plate along the axial direction of the lead screw, the first stop protrusion and the second stop protrusion are engaged to limit the retraction of the push rod nut and achieve braking.

2. The actuator of the automotive EMB braking system according to claim 1, characterized in that, The stop plate has a positioning groove on the side surface facing the push rod nut. The annular baffle is embedded in the positioning groove. The positioning groove wall has a positioning protrusion. The outer circumferential surface of the annular baffle has a positioning groove. The positioning protrusion and the positioning groove are engaged. The first stop protrusion is located on the side surface of the stop plate facing the push rod nut and outside the positioning groove, and the second stop protrusion is located on the side surface of the push rod nut facing the stop plate.

3. The actuator of the automotive EMB braking system according to claim 2, characterized in that, The positioning protrusions are provided in multiple ways, and the multiple positioning protrusions are evenly distributed along the circumference of the lead screw. The positioning grooves are provided in multiple ways, and the multiple positioning protrusions and multiple positioning grooves correspond one-to-one.

4. The actuator of the automotive EMB braking system according to claim 1, characterized in that, The inner wall of the housing is provided with an annular partition, which divides the chamber inside the housing into a front chamber and a rear chamber. The lead screw is inserted into the annular partition, and the two ends of the lead screw are located in the front chamber and the rear chamber, respectively. The lead screw is also fitted with a locking nut assembly and a pressure plate. The locking nut assembly is threadedly engaged with the lead screw. The locking nut assembly and the push rod nut are located on both sides of the annular partition. The locking nut assembly is used to press the pressure plate onto the annular partition.

5. The actuator of the automotive EMB braking system according to claim 4, characterized in that, The lead screw is also fitted with a lip-shaped sealing ring, which is pressed between the inner circumferential surface of the annular partition and the outer circumferential surface of the lead screw.

6. The actuator of the automotive EMB braking system according to claim 4, characterized in that, The annular partition plate is further provided with an annular boss on the side surface facing the pressure plate. A flat bearing is fitted on the outer circumference of the annular boss, and the flat bearing is pressed between the pressure plate and the annular partition plate.

7. The actuator of the automotive EMB braking system according to claim 4, characterized in that, The locking nut assembly includes a locking nut and a washer. The locking nut is threaded into the lead screw, and the washer is pressed between the locking nut and the pressure plate.

8. The actuator of the automotive EMB braking system according to claim 1, characterized in that, The output push rod has a keyway on its outer circumferential surface, and a guide key is provided in the keyway. The guide key is located between the outer circumferential surface of the push rod nut and the inner wall of the housing.

9. The actuator of the automotive EMB braking system according to claim 1, characterized in that, The front end of the output push rod is also fitted with a sliding sleeve.

10. The actuator of the automotive EMB braking system according to claim 1, characterized in that, The drive assembly includes a drive motor, and the transmission assembly includes a first gear, a second gear, and a third gear that mesh in sequence. The diameter of the first gear is smaller than the diameter of the third gear. The first gear is connected to the drive motor, and the third gear is mounted on the lead screw.

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