Electric linear drive for headrests

Abstract

The utility model discloses a headrest electric linear driver, include: install in the motor in bottom shell, install the first stage bevel gear on the output shaft of motor and be located in bottom shell, install the intermediate gear assembly in bottom shell, intermediate gear assembly has the coaxial second stage bevel gear and second stage worm, and the second stage bevel gear is engaged with the first stage bevel gear, can rotatable installation in bottom shell of lead screw, and the bevel gear nut of driving lead screw rotation is fixed to one end of lead screw, and the bevel gear nut is engaged with second stage worm, the adjusting block that carries out linear motion and is used for adjusting headrest height position or vertical angle or side wing position and angle is provided with in both ends of lead screw, and the adjusting block is adjusted headrest height position or vertical angle or side wing position and angle through the cable, the utility model discloses structure compares traditional face tooth and rack drive system structure more compact, makes the space of headrest adjusting executor as small as possible.

Description

Technical Field

[0001] This utility model relates to the field of automotive seat headrest technology, and in particular to an electric linear actuator for a headrest. Background Technology

[0002] Traditional car seat headrests are manually adjustable for height and vertical angle, while the side wings are manually adjustable with damping.

[0003] First, the headrest's height and vertical angle are both non-linearly adjustable, with only a few preset height settings for both. This makes it difficult to precisely adjust the position based on the passenger's specific sitting height, thus failing to provide perfect comfort.

[0004] Secondly, the height adjustment function is difficult to operate manually. The headrests of various car models are relatively difficult to adjust. Due to the imbalance of the internal locking mechanism and the installation error of the guide rail, they are prone to jamming. It is necessary to shake them and then pull them out or press them down with considerable force to adjust them. Moreover, it cannot be adjusted when the passenger is sitting, and it is even more difficult to match them to the right position, requiring multiple adjustments.

[0005] Finally, the internal structure for vertical angle adjustment is generally a cyclic ratchet mechanism, which can only operate and adjust in one direction. If it is not adjusted properly, it has to be started all over again. Moreover, it is easy to get stuck and difficult to reset when resetting at a high position.

[0006] In summary, adjusting the headrest requires an electric adjustment motor to drive the headrest's adjustment in all directions. Utility Model Content

[0007] The technical problem to be solved by this utility model is to provide an electric linear actuator for a headrest, which addresses the aforementioned technical problems caused by the manual adjustment of the height and vertical angle of traditional car seat headrests, and the damped manual folding adjustment of the side wings.

[0008] The technical problem to be solved by this utility model can be achieved through the following technical solution: A headrest electric linear actuator includes: a bottom shell and a top cover; and further includes: The motor is installed inside the bottom housing; A first-stage bevel gear or a first-stage worm gear mounted on the output shaft of the motor and located inside the bottom housing; An intermediate gear assembly or a double gear is installed inside the bottom shell; the intermediate gear assembly has a second-stage bevel gear and a second-stage worm gear arranged coaxially, the second-stage bevel gear meshing with the first-stage bevel gear; or the double gear has a second-stage helical gear and a second-stage worm gear arranged coaxially, the first-stage worm gear meshing with the second-stage helical gear; A lead screw is rotatably installed inside the bottom shell. A helical tooth nut that drives the lead screw to rotate is fixed at one end of the lead screw. The helical tooth nut meshes with the second-stage worm gear. Adjustment blocks that perform linear motion and are used to adjust the height, vertical angle, or side wing position and angle of the headrest are provided at both ends of the lead screw. The adjustment blocks adjust the height, vertical angle, or side wing position and angle of the headrest through a cable.

[0009] In a preferred embodiment of this utility model, the helical tooth nut is a cylindrical helical gear nut, which is integrally formed with the lead screw.

[0010] In a preferred embodiment of this utility model, sliding bearings or sliding bushings are added to the lead screws at both ends of the helical tooth nut.

[0011] In a preferred embodiment of this utility model, the adjusting block engages with the mounting position on the headrest to prevent rotation.

[0012] In a preferred embodiment of this utility model, the adjusting block and the lead screw are fixed by in-mold injection molding, thereby enabling the lead screw to drive the adjusting blocks at both ends to achieve linear motion.

[0013] In a preferred embodiment of this utility model, the motor is a square motor.

[0014] In a preferred embodiment of this utility model, the motor is arranged parallel or perpendicular to the lead screw.

[0015] Due to the adoption of the above technical solution, the structure of this utility model is more compact than that of traditional gear and rack transmission systems, minimizing the space occupied by the headrest adjustment actuator. The integrated design of the cylindrical helical gear nut and the mechanism of the screw-nut combination not only improves transmission efficiency but also adds sliding bearings (shiels) at both ends of the cylindrical helical gear nut, preventing direct friction between the cylindrical surface of the gear and the base shell, thus reducing the risk of wear and failure after prolonged use. Attached Figure Description

[0016] Figure 1 This is a top view of the headrest electric linear actuator of Embodiment 1 of this utility model.

[0017] Figure 2 This is one of the three-dimensional exploded schematic diagrams of the headrest electric linear actuator of Embodiment 1 of this utility model.

[0018] Figure 3 This is the second exploded perspective view of the headrest electric linear actuator of Embodiment 1 of this utility model.

[0019] Figure 4 This is a top view of the headrest electric linear actuator of Embodiment 2 of this utility model.

[0020] Figure 5 This is one of the three-dimensional exploded schematic diagrams of the headrest electric linear actuator of Embodiment 2 of this utility model.

[0021] Figure 6 This is the second exploded perspective view of the headrest electric linear actuator of Embodiment 2 of this utility model.

[0022] Figure 7 This is a top view of the headrest electric linear actuator of Embodiment 2 of this utility model.

[0023] Figure 8 This is one of the three-dimensional exploded schematic diagrams of the headrest electric linear actuator of Embodiment 2 of this utility model.

[0024] Figure 9 This is the second exploded perspective view of the headrest electric linear actuator of Embodiment 2 of this utility model. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Example 1

[0026] See Figures 1 to 3 The headrest electric linear actuator shown in the figure includes: a bottom shell 100, a top cover 200, a motor 300, a first-stage bevel gear 400, an intermediate gear assembly 500, and a lead screw 600.

[0027] The motor 300 is a square motor, but it can also be a non-square motor. The motor 300 is installed in the motor mounting cavity 110 inside the bottom shell 100. The first-stage bevel gear 400 is fixed on the output shaft of the motor 300 and located in the bevel gear cavity 120 inside the bottom shell 100. The bevel gear cavity 120 is connected to the motor mounting cavity 110.

[0028] The intermediate gear assembly 500 is installed in the intermediate gear assembly mounting cavity 130 of the base shell 100. The intermediate gear assembly 500 has a second-stage bevel gear 510 and a second-stage worm gear 520 arranged coaxially. The second-stage bevel gear 510 and the second-stage worm gear 520 are a double structure. The intermediate gear assembly mounting cavity 130 is connected to the bevel gear cavity 120.

[0029] A rotatable portion of the lead screw 600 is installed in the lead screw cavity 140 of the bottom shell 100. A portion of the lead screw 600, namely both ends of the lead screw 600, extends out of the bottom shell 100. The lead screw cavity 140 is connected to the intermediate gear assembly mounting cavity 130.

[0030] A helical nut 610 is fixed at one end of the lead screw 600 to drive the lead screw 600 to rotate. The helical nut 610 is a cylindrical helical gear nut and is integrally formed with the lead screw 600. Sliding bearings 620 or sliding bushings are added to the lead screw 600 at both ends of the helical nut 610 to avoid direct friction between the cylindrical surface of the gear of the cylindrical helical gear nut and the bottom shell 100.

[0031] When installing the lead screw 600, it can be positioned parallel to the motor 300 (Example 1) or perpendicular to it (Example 2) as needed. To drive the headrest, adjusting blocks 630 and 640 are provided at both ends of the lead screw 600. These blocks allow linear motion and are used to adjust the headrest's height, vertical angle, or side wing position and angle. The adjusting blocks 630 and 640 are adjusted via cables. The adjusting blocks 630 and 640 engage with mounting points on the headrest to prevent rotation. The adjusting blocks 630 and 640 are fixed to the lead screw 600 using in-mold injection molding, thereby enabling the lead screw to drive the adjusting blocks 630 and 640 at both ends to achieve linear motion.

[0032] When the headrest needs to be adjusted, the motor 300 is started. The first-stage bevel gear 400 on the output shaft of the motor 300 meshes with the second-stage bevel gear 510 on the intermediate gear assembly 500, driving the second-stage worm gear 520 to rotate. The second-stage worm gear 520 meshes with the helical nut 610, driving the lead screw 600 to rotate. The adjusting blocks 630 and 640 adjust the height, vertical angle, or side wing position and angle of the headrest via the pull cable. Example 2

[0033] See Figures 4 to 9 The headrest electric linear actuator shown in the figure includes: a bottom shell 100, a top cover 200, a motor 300, a first-stage worm gear 400a, a double gear 500a, and a lead screw 600.

[0034] The motor 300 is a square motor, but it can also be a non-square motor. The motor 300 is installed in the motor mounting cavity 110 inside the bottom shell 100. The first-stage worm gear 400a is fixed on the output shaft of the motor 300 and located in the bevel gear cavity 120 inside the bottom shell 100. The bevel gear cavity 120 is connected to the motor mounting cavity 110.

[0035] The double gear 500a is installed in the intermediate gear assembly mounting cavity 130 of the bottom shell 100. The double gear 500a has a second-stage helical gear 510a and a second-stage worm gear 520 arranged coaxially. The intermediate gear assembly mounting cavity 130 is connected to the bevel gear cavity 120.

[0036] A rotatable portion of the lead screw 600 is installed in the lead screw cavity 140 of the bottom shell 100. A portion of the lead screw 600, namely both ends of the lead screw 600, extends out of the bottom shell 100. The lead screw cavity 140 is connected to the intermediate gear assembly mounting cavity 130.

[0037] A helical nut 610 is fixed at one end of the lead screw 600 to drive the lead screw 600 to rotate. The helical nut 610 is a cylindrical helical gear nut and is integrally formed with the lead screw 600. Sliding bearings 620 or sliding bushings are added to the lead screw 600 at both ends of the helical nut 610 to avoid direct friction between the cylindrical surface of the gear of the cylindrical helical gear nut and the bottom shell 100.

[0038] When installing the lead screw 600, it can be positioned parallel to the motor 300 (Example 1) or perpendicular to it (Example 2) as needed. To drive the headrest, adjusting blocks 630 and 640 are provided at both ends of the lead screw 600. These blocks allow linear motion and are used to adjust the headrest's height, vertical angle, or side wing position and angle. The adjusting blocks 630 and 640 are adjusted via cables. The adjusting blocks 630 and 640 engage with mounting points on the headrest to prevent rotation. The adjusting blocks 630 and 640 are fixed to the lead screw 600 using in-mold injection molding, thereby enabling the lead screw to drive the adjusting blocks 630 and 640 at both ends to achieve linear motion.

[0039] When the headrest needs to be adjusted, the motor 300 is started. The first-stage worm gear 400a on the output shaft of the motor 300 meshes with the second-stage helical gear 510a on the double gear 500a, driving the second-stage worm gear 520 to rotate. The second-stage worm gear 520 meshes with the helical nut 610, driving the lead screw 600 to rotate. The adjusting blocks 630 and 640 adjust the height, vertical angle, or side wing position and angle of the headrest through the pull cable.

Claims

1. A headrest electric linear actuator, comprising: The bottom shell and top cover; also includes: The motor is installed inside the bottom housing; A first-stage bevel gear or a first-stage worm gear mounted on the output shaft of the motor and located inside the bottom housing; An intermediate gear assembly or a double gear is installed inside the bottom shell; the intermediate gear assembly has a second-stage bevel gear and a second-stage worm gear arranged coaxially, the second-stage bevel gear meshing with the first-stage bevel gear; or the double gear has a second-stage helical gear and a second-stage worm gear arranged coaxially, the first-stage worm gear meshing with the second-stage helical gear; A lead screw is rotatably installed inside the bottom shell. A helical tooth nut that drives the lead screw to rotate is fixed at one end of the lead screw. The helical tooth nut meshes with the second-stage worm gear. Adjustment blocks that perform linear motion and are used to adjust the height, vertical angle, or side wing position and angle of the headrest are provided at both ends of the lead screw. The adjustment blocks adjust the height, vertical angle, or side wing position and angle of the headrest through a cable.

2. The headrest electric linear actuator according to claim 1, characterized in that, The helical tooth nut is a cylindrical helical gear nut, which is integrally formed with the lead screw.

3. A headrest electric linear actuator according to claim 1, characterized in that, Sliding bearings or sliding bushings are added to the lead screws at both ends of the helical tooth nut.

4. The headrest electric linear actuator according to claim 1, characterized in that, The adjusting block engages with the mounting position on the headrest to prevent rotation.

5. A headrest electric linear actuator according to claim 1, characterized in that, The adjusting block and the lead screw are fixed by in-mold injection molding, thereby enabling the lead screw to drive the adjusting blocks at both ends to achieve linear movement.

6. A headrest electric linear actuator according to claim 1, characterized in that, The motor is a square motor.

7. A headrest electric linear actuator according to claim 1, characterized in that, The motor is arranged parallel or perpendicular to the lead screw.

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