Linear electric drive

Abstract

The utility model relates to a linear electric drive device, it includes drive motor, the slide rail of longitudinal extension, screw rod and the travelling assembly of movably arranged on the slide rail, wherein, the travelling assembly includes the slider and screw rod nut that can separate each other, wherein, the screw rod is with screw rod nut screw connection, and the screw rod is with the slider sliding connection, wherein, when the drive motor runs in the first rotation direction, the slider is together with screw rod nut and moves away from the drive motor along the longitudinal direction together, and when the drive motor runs in the second rotation direction opposite to the first rotation direction, the screw rod nut separates relative to the slider and moves to the drive motor.

Description

Technical Field

[0001] This utility model relates to a linear electric drive device. Background Technology

[0002] As society develops, people's demands for daily necessities and products are becoming increasingly sophisticated. They not only expect furniture to have more diverse functions, but also place increasingly stringent requirements on its safety performance. For example, in the case of electric sofas, multifunctional electric sofas often have multiple movable units, such as movable leg units, backrest units, and even movable armrest units, to meet the diverse needs of users for different seating postures.

[0003] The electric sofa uses electro-actuators to move its various movable units, allowing it to shift between at least two of the following positions: sitting, TV position, and reclining position. However, in the "extended" positions such as the TV or reclining positions, the movable units extend away from the sofa base. For example, the space between the footrest of the leg unit and the sofa base is exposed, making it possible for foreign objects to enter this space and prevent the electric sofa from returning to its original position. More seriously, if a living being, such as a pet or even a child, accidentally enters this space, they could be trapped during the sofa's repositioning process, resulting in injury or death to the pet or person.

[0004] To avoid such hazards, various preventative measures have been implemented. Some existing designs incorporate protective panels on moving parts to block external access and prevent foreign objects or living beings from entering areas where they might get stuck. However, these panels not only hinder the furniture's freedom of movement and increase the structural space required for installation, but also negatively impact its appearance. Other existing designs use capacitive or infrared sensors to detect foreign objects or living beings entering areas at risk of getting stuck. However, these sensors suffer from significant measurement errors, unstable operation, complex connections, and high energy consumption. Utility Model Content

[0005] In view of this, the technical problem to be solved by this utility model is to reliably prevent the risk of pinching injury in a simpler way.

[0006] Therefore, this utility model relates to a linear electric drive device, which includes a drive motor, a longitudinally extending slide rail, a lead screw, and a traveling assembly movably arranged on the slide rail; wherein the traveling assembly includes a separable slider and a lead screw nut, wherein the lead screw and the lead screw nut are threadedly connected, and the lead screw is slidably connected to the slider, wherein when the drive motor is running in a first rotation direction, the slider together with the lead screw nut moves longitudinally away from the drive motor, and when the drive motor is running in a second rotation direction opposite to the first rotation direction, the lead screw nut separates from the slider and moves toward the drive motor.

[0007] In a slider motor, the slider acts as an actuator, moving along a slide rail. The position of the object to be driven is adjusted by changing the distance between the slider and the drive motor.

[0008] In existing slider motors, the slider with internal threads is always threadedly connected to the lead screw to convert the torque of the lead screw into linear movement. When the lead screw rotates in a first or second direction under the drive of the motor, the slider translates on the slide rail in the opposite linear direction accordingly.

[0009] Unlike existing technologies, this invention features a split-structure traveling assembly, in which the slider and threaded portion are manufactured separately. Specifically, it provides a slider that is not threadedly connected to the lead screw and a lead screw nut that is threadedly connected to the lead screw, the lead screw nut being slidably arranged within the slider. In this configuration, when the drive motor rotates in a first direction, the longitudinal displacement of the lead screw nut in one direction pushes the slider to translate in the same direction. Conversely, when the drive motor rotates in a second direction, the lead screw nut displaces longitudinally in the opposite direction and moves away from the slider, preventing the slider from moving in the opposite direction along with the lead screw nut. This achieves a "push-only" linear electric drive device. This "push-only" property ensures that the linear electric drive device can apply torque to the object being driven in only one direction, thus preventing injury to people or objects during the reset stroke of the linear electric drive device.

[0010] According to one embodiment of the present invention, the slider includes an axial stop section, the axial stop section including a smooth through hole through which a lead screw can pass, the axial stop section and the lead screw nut being arranged longitudinally adjacent to each other, wherein when the drive motor is running in a first rotation direction, the lead screw nut applies a longitudinal thrust to the axial stop section, and when the drive motor is running in a second rotation direction, the lead screw nut is separated from the axial stop section.

[0011] The axial stop section and the lead screw nut are arranged adjacent to each other along the longitudinal direction, such that one side of the axial stop section forms a stop surface for the lead screw nut. When the drive motor runs in the first rotation direction, the lead screw nut abuts against the stop surface and applies thrust to the slider; when the drive motor runs in the second rotation direction, the lead screw nut moves away from the stop surface, thereby decoupling from the slider's power.

[0012] According to one embodiment of the present invention, the lead screw nut is accommodated in the slider with a clearance fit.

[0013] The clearance fit between the lead screw nut and the slider ensures that the lead screw nut can be loosely positioned in the slider, so that the lead screw nut can smoothly separate from the slider when the drive motor reverses.

[0014] According to one embodiment of the present invention, in a cross section perpendicular to the longitudinal direction, the lead screw nut includes at least one protruding arm, and the slider includes a guide groove extending along the longitudinal direction, wherein the protruding arm is movably fitted into the guide groove.

[0015] Preferably, the lead screw nut includes two opposing protrusions and a protrusion disposed between the protrusions.

[0016] The protruding arm and the optional protrusion ensure that the screw nut does not rotate with the screw, thus reliably converting the torque transmitted by the screw into a linear torque. On the other hand, they ensure the stability and accurate orientation of the screw nut during operation.

[0017] According to one embodiment of the present invention, the slider includes a longitudinally extending slide rail receiving channel, wherein the slide rail guides through the slide rail receiving channel.

[0018] According to an alternative embodiment of the present invention, the lead screw nut includes a longitudinally extending slide rail receiving portion, and the slider includes a longitudinally extending nut receiving channel, wherein the slide rail guides through the slide rail receiving portion, and the slide rail receiving portion is slidably arranged in the nut receiving channel.

[0019] According to one embodiment of the present invention, the slide rail receiving portion has a closed profile in a cross-section perpendicular to the longitudinal direction.

[0020] According to one embodiment of the present invention, the lead screw nut extends longitudinally over a region comprising at least half the length of the slider. Thus, the lead screw nut provides a sufficient number of thread turns for threaded connection with the lead screw to ensure a stable and reliable connection.

[0021] According to one embodiment of the present invention, the drive motor includes a motor shaft, wherein the motor shaft is connected to the lead screw.

[0022] According to one embodiment of this utility model, the motor shaft is connected to the lead screw via a worm gear. Alternatively, other transmission methods can be used to connect the motor shaft and the lead screw, such as a gear transmission assembly. Attached Figure Description

[0023] Figure 1 A schematic top view of a linear electric drive device according to one embodiment of the present invention is shown;

[0024] Figure 2 An exploded view schematically illustrates a linear electric drive device according to one embodiment of the present invention;

[0025] Figure 3 schematically shown Figure 1 A partial interior view of the area shown;

[0026] Figure 4 A perspective view schematically illustrates a portion of the components of a linear electric drive device according to one embodiment of the present invention, including a traveling assembly assembled together.

[0027] Figure 5 schematically shown Figure 4 Side view of the component shown;

[0028] Figure 6 schematically shown Figure 4 A 3D view of the slider shown;

[0029] Figure 7 schematically shown Figure 4 A 3D view of the lead screw and nut shown;

[0030] Figure 8 schematically shown Figure 1 The sectional view obtained by the cutting line AA shown;

[0031] Figure 9 schematically shown Figure 1 The sectional view obtained by the cutting line BB shown;

[0032] Figure 10 A perspective view of the lead screw nut of a linear electric drive device according to another embodiment of the present invention is shown schematically.

[0033] Figure 11 A perspective view schematically illustrating the slider of a linear electric drive device according to another embodiment of the present invention is shown; and

[0034] Figure 12 The schematic diagram shows a side view of some components of a linear electric drive device according to another embodiment of the present invention, including a traveling assembly assembled together. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] The term "one embodiment" or "implementation" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this utility model. In the description of this utility model, it should be understood that the terms "upper," "lower," "left," "right," "top," "bottom," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not 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. 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 indicated technical features. Thus, a feature defined with "first" and "second" may explicitly or implicitly include one or more of that feature. Moreover, the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this utility model described herein can be implemented in orders other than those illustrated or described herein.

[0037] Unless otherwise stated, the term "longitudinal" in this invention refers to the longitudinal extension direction of the slide rail of the linear electric drive device.

[0038] Figure 1 A perspective view of a linear electric drive device 100 according to one embodiment of the present invention is shown schematically. Figure 2 An exploded view of the linear electric drive device 100 is shown schematically.

[0039] The linear electric drive device 100 is configured as a slider motor. Specifically, it includes a drive motor 1, a transmission box 2, a slide rail 3, a lead screw 5, and a traveling assembly, which includes a slider 4 and a lead screw nut 6. The slide rail 3 is fixedly connected to the drive motor 1, and the slider 4 is slidably arranged on the slide rail 3.

[0040] The drive motor 1 includes a motor shaft 11. For example, when the drive motor 1 rotates forward, the motor shaft 11 rotates along a first rotation direction; when the drive motor 1 rotates in reverse, the motor shaft 11 rotates along a second rotation direction opposite to the first rotation direction. Of course, it can also be configured in the opposite way, that is, when the drive motor 1 rotates forward, the motor shaft 11 rotates along the second rotation direction; when the drive motor 1 rotates in reverse, the motor shaft 11 rotates along the first rotation direction.

[0041] A drive motor 1 is fixedly connected to a transmission housing 2. A transmission mechanism is arranged in the transmission housing 2 to transmit the torque output from the motor shaft 11 to the lead screw 5. Exemplarily, the transmission housing 2 may include a first sub-housing 21, a second sub-housing 22, and a cover 23, wherein the first sub-housing 21, the second sub-housing 22, and the cover 23 are engaged with each other to form a hollow receiving cavity. A transmission mechanism, such as a worm gear 12, arranged in this receiving cavity meshes with the motor shaft 11 and the lead screw 5 respectively to transmit the torque output from the motor shaft 11 to the lead screw 5.

[0042] The slide rail 3 extends longitudinally (x) and is fixedly connected at one end to the transmission housing 2. Exemplarily, the slide rail 3 includes an upper rail portion 31 and a lower rail portion 32, which define an inner cavity within the slide rail, in which the lead screw 5 is housed. An end cap 33 closes the inner cavity at the free end of the slide rail 3 opposite to the end fixedly connected to the transmission housing 2. Furthermore, a limiting strip 34 with a limit sensor is arranged within the inner cavity of the slide rail.

[0043] like Figures 4 to 7 As shown, the slider 4 includes a base 40 and an axial stop section 41 fixedly connected to the base 40. The axial stop section 41 includes a through hole 4a extending longitudinally x, the through hole 4a having a smooth inner wall, i.e., without internal threads, thereby enabling slidable connection with the lead screw 5. The lead screw nut 6 includes a threaded hole 6a extending longitudinally x for threaded connection with the lead screw 5. In the assembled state, the lead screw nut 6 is slidably arranged in the slider 4 and extends longitudinally x over a portion of the length of the slider 4, for example, extending over half the length of the slider 4 along the longitudinal x direction.

[0044] In this embodiment, in a cross-section perpendicular to the longitudinal direction x, the lead screw nut 6 includes two opposing protruding arms 61 and a protrusion 62 disposed between the protruding arms 61. Accordingly, a guide groove 42 extending along the longitudinal direction x is provided in the slider 4, wherein the protruding arms 61 of the lead screw nut 6 are slidably embedded in the guide groove 42.

[0045] In this embodiment, the lead screw nut 6 is arranged in the slider 4 with clearance fit, and one end of the lead screw nut 6 is adjacent to the axial stop section 41.

[0046] In this embodiment, the slider 4 also includes a slide rail receiving channel 43 extending longitudinally x. The slide rail 3 is guided through the slide rail receiving channel 43, thereby allowing the slider 4 to slide relative to the guide rail 3.

[0047] Figure 8 An exemplary schematic diagram is shown passing through the region of the lead screw nut 6 along the cutting line AA. Figure 9 An exemplary schematic diagram is shown in the region passing through the axial stop section 41 along the section line AA.

[0048] In the assembled state, the slide rail 3 is guided through the slide rail receiving channel 43 formed by the slider 4. The lead screw nut 6 is arranged in the slider 4, wherein the protruding arm 61 of the lead screw nut 6 is embedded in the guide groove of the slider 4, and the protrusion 62 is engaged with the mating part provided by the upper part 31 of the slide rail 3. This ensures that the lead screw nut 6 operates stably without wobbling. The lead screw 5 passes through both the threaded hole 6a of the lead screw nut 6 and the through hole 4a of the axial stop section 41. Since the lead screw 5 is threadedly connected to the lead screw nut 6 by its external thread, the lead screw 5 transmits torque to the lead screw nut 6 and causes the lead screw nut 6 to move longitudinally x. The through hole 4a has a smooth inner wall, so there is no threaded connection between the slider 4 and the lead screw 5.

[0049] In this situation, when the drive motor 1 is running in the first rotation direction, the lead screw nut 6 translates longitudinally (x) towards the axial stop section 41, pushing the slider 4 to move away from the drive motor 1. However, when the drive motor 1 is running in the second rotation direction, the lead screw nut 6 displaces in the opposite direction longitudinally (x) and moves away from the slider 4. At this time, the slider 4 cannot move in the opposite direction along with the lead screw nut 6.

[0050] Figures 10 to 12 This illustration schematically shows another embodiment of the present invention.

[0051] In this embodiment, the lead screw nut 6 includes a slide rail receiving portion 63 extending along the longitudinal direction x, through which the slide rail 3 is guided. In a cross-section perpendicular to the longitudinal direction x, the slide rail receiving portion 63 has a closed profile, thereby making the operation of the lead screw nut 6 on the slide rail 3 particularly stable. Correspondingly, the slider 4 includes a nut receiving channel 44 extending along the longitudinal direction x, in which the slide rail receiving portion 63 is slidably arranged.

Claims

1. A linear electric drive device, characterized in that, The linear electric drive device includes a drive motor, a longitudinally extending slide rail, a lead screw, and a traveling assembly movably arranged on the slide rail. The traveling assembly includes a separable slider and a lead screw nut, wherein the lead screw is threadedly connected to the lead screw nut and slidably connected to the slider. When the drive motor is running in a first rotational direction, the slider and the lead screw nut move longitudinally away from the drive motor. When the drive motor is running in a second rotational direction opposite to the first rotational direction, the lead screw nut separates from the slider and moves toward the drive motor.

2. The linear electric drive device according to claim 1, characterized in that, The slider includes an axial stop section with a smooth through hole through which a lead screw passes. The axial stop section is arranged longitudinally adjacent to the lead screw nut. When the drive motor is running in a first rotational direction, the lead screw nut applies a longitudinal thrust to the axial stop section, and when the drive motor is running in a second rotational direction opposite to the first rotational direction, the lead screw nut separates from the axial stop section.

3. The linear electric drive device according to claim 1, characterized in that, The lead screw nut is accommodated in the slider with a clearance fit.

4. The linear electric drive device according to claim 3, characterized in that, In a cross-section perpendicular to the longitudinal direction, the lead screw nut includes at least one protruding arm, and the slider includes a guide groove extending along the longitudinal direction, wherein the protruding arm is movably fitted into the guide groove.

5. The linear electric drive device according to claim 4, characterized in that, The lead screw nut includes two opposing protrusions and a protrusion disposed between the protrusions.

6. The linear electric drive device according to any one of claims 1 to 5, characterized in that, The slider includes a longitudinally extending slide rail receiving channel, through which the slide rail is guided.

7. The linear electric drive device according to any one of claims 1 to 3, characterized in that, The lead screw nut includes a longitudinally extending slide rail receiving portion, and the slider includes a longitudinally extending nut receiving channel, wherein the slide rail is guided through the slide rail receiving portion, and the slide rail receiving portion is slidably arranged in the nut receiving channel.

8. The linear electric drive device according to claim 7, characterized in that, The slide rail receiving portion has a closed profile in a cross-section perpendicular to the longitudinal direction.

9. The linear electric drive device according to claim 1, characterized in that, The lead screw nut extends longitudinally over a region that is at least half the length of the slider.

10. The linear electric drive device according to claim 1, characterized in that, The drive motor includes a motor shaft, wherein the motor shaft is connected to the lead screw drive.

11. The linear electric drive device according to claim 10, characterized in that, The motor shaft is connected to the lead screw via a worm gear.

Images