Driving mechanism for driving item to be folded or unfolded

Abstract

Provided in the present application is a driving mechanism for driving an item to be folded or unfolded. The driving mechanism comprises a screw, a driving pulley, a transmission member and a first driving device, wherein one end of the transmission member is connected to an item, and the other end of the transmission member is connected to the driving pulley; at least two sections of external threaded grooves having different screw pitches are provided on the periphery of the screw; the driving pulley is arranged in the external threaded groove; the first driving device drives the screw to rotate; the screw drives the driving pulley by means of the external threaded groove to move along the external threaded groove; the external threaded grooves comprise a fine-pitch zone and a coarse-pitch zone; when the driving pulley moves from the fine-pitch zone towards the coarse-pitch zone, the item performs an unfolding motion; and when the driving pulley moves from the coarse-pitch zone to the fine-pitch zone, the item performs a folding motion. By using the screw and the external thread grooves in the present application, higher precision and controllability can be provided. The driving mechanism of the present application requires relatively less maintenance, does not require lubrication, and can be adapted to various complex outdoor environments.

Description

A driving mechanism for driving an object to fold or unfold Technical Field

[0001] The present application relates to the field of object driving, and in particular to a driving mechanism for driving an object to fold or unfold. Background Art

[0002] Objects (such as blades, curtains, doors, etc.), for example, are used in blinds. Blinds in the prior art include multiple objects arranged side by side, and each object can move synchronously.

[0003] A mobile rotating blind is disclosed in the prior art, with publication number CN113047760B and publication date 2021-03-10. It discloses a mobile rotating blind, including a guide rail, multiple blinds and an electrical control box, as well as a rotating system for controlling the rotation of multiple blinds, and a mobile system for controlling the movement of multiple blinds; the rotating system includes a push rod motor, a long connecting rod, a short connecting rod, a connecting block, a fixed-distance chain, a blind short shaft, a pulley and an anti-fall frame; the mobile system is arranged on the guide rail; the mobile system includes a motor, a main sprocket, a slave sprocket, a chain, a main shaft, a blind long shaft and a traction block.

[0004] The existing technology uses chains and sprockets to drive the shutters to move, and its disadvantages are:

[0005] (1) The sprocket chain system requires regular maintenance and lubrication, especially in complex outdoor environments. The lubricant may be more likely to fail, become thinner or thicker, and lose its lubricating properties. This causes increased friction in the sprocket chain system, thereby affecting its operating efficiency and increasing wear. This increases maintenance costs and downtime.

[0006] (2) In areas with complex or dusty environments, the sprocket chain system is more susceptible to dust, moisture and other environmental factors, which may cause the chain to get stuck or run poorly.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to provide a driving mechanism for folding or unfolding an object, which is easy to maintain, suitable for complex outdoor environments, and has low noise.

[0009] In order to achieve the above objectives, this application provides the following technical solutions:

[0010] A driving mechanism for driving an object to be folded or unfolded includes a screw, a driving pulley, a transmission member and a first driving device, one end of the transmission member is connected to the object, and the other end of the transmission member is connected to the driving pulley, the outer periphery of the screw is provided with at least two sections of external thread grooves with different pitches, the driving pulley is arranged in the external thread groove, the first driving device drives the screw to rotate, and the screw drives the driving pulley to move along the external thread groove through the external thread groove, the external thread groove includes a small pitch area and a large pitch area, when the driving pulley moves from the small pitch area to the large pitch area, the object performs an unfolding motion, and when the driving pulley moves from the large pitch area to the small pitch area, the object performs a folding motion.

[0011] Furthermore, the driving mechanism also includes a guiding device, which is used to assist in guiding the object during the folding or unfolding movement. The guiding device includes a guide rail and a guide pulley. The guide pulley is rotatably mounted on the transmission member, and the guide pulley can move relative to the guide rail.

[0012] Furthermore, the driving mechanism also includes an angle adjustment device, which is used to adjust the angle of the object. The angle adjustment device includes a central shaft, a first docking part, a second docking part and an adjustment driving device. The central shaft is rotatably installed on the transmission member. One end of the central shaft is connected to the object, and the other end of the central shaft is connected to the first docking part. The driving pulley drives the first docking part to move to the second docking part through the transmission member. The first docking part and the second docking part are docked with each other. The adjustment driving device can drive the second docking part to perform rotational motion, and the second docking part drives the first docking part to perform rotational motion. The first docking part drives the object to perform rotational motion through the central shaft.

[0013] Furthermore, the second docking part includes a docking seat, a docking shaft, a docking drive handle and a connecting rod, one end of the docking shaft is connected to the docking seat, and the other end of the docking shaft is connected to the docking shaft. A first drive slider is rotatably installed near at least one end of the docking shaft, and the first drive slider is slidably installed on the connecting rod. The adjusting drive device can drive the first drive slider through the connecting rod to drive the docking drive handle to rotate, and the docking drive handle drives the docking shaft and the docking seat to rotate.

[0014] Furthermore, two connecting rods are provided.

[0015] Furthermore, a docking groove is provided on the docking seat corresponding to the first docking portion.

[0016] Furthermore, the first docking portion can be inserted into the docking groove to cooperate with the second docking portion.

[0017] Furthermore, the first docking portion includes a docking piece and a docking roller, one side of the docking piece is mounted on the central shaft, and the docking rollers are symmetrically arranged on the other side of the docking piece, and the docking rollers can slide into the docking groove of the docking seat.

[0018] Furthermore, the adjustment drive device includes an adjustment drive handle, a drive shaft and a drive assembly, the adjustment drive handle is installed on the drive shaft, the adjustment drive handle is connected to the connecting rod through a second drive slider, the drive assembly can drive the adjustment drive handle to rotate around the drive shaft, and the adjustment drive handle drives the connecting rod to perform lifting and lowering movements through the second drive slider.

[0019] Furthermore, the driving assembly includes a driving screw, a driving nut and a driving protrusion, the driving protrusion is installed on the driving nut, and the driving nut is installed on the driving screw. The driving screw can drive the driving nut to drive the driving protrusion to perform lifting movements, and the raised portion of the driving protrusion cooperates with the driving slot of the adjusting driving handle. The driving protrusion performs lifting movements in the driving slot, thereby driving the adjusting driving handle to rotate around the driving shaft.

[0020] The beneficial effects of this application are:

[0021] When the present invention unfolds an object from a folded state to an unfolded state, the first drive device first drives the screw to rotate. At this time, the drive pulley in the small pitch area drives the object to move along the external thread groove toward the large pitch area, so that the object is unfolded. When the object in the unfolded state needs to be folded together, the first drive device also drives the screw to rotate in the opposite direction, so that the drive pulley in the large pitch area drives the object to move along the external thread groove toward the small pitch area, thereby achieving the folding of the object. Compared with the existing technology, the advantages of the present invention are:

[0022] (1) The present invention uses a screw and external thread groove to provide higher precision and controllability. The external thread groove with different pitches can achieve precise motion control, allowing the object to be smoothly expanded and retracted.

[0023] (2) Compared with the sprocket chain system, the chain needs to be lubricated and replaced regularly, which is not suitable for complex outdoor environments. This application requires less maintenance and does not require lubrication, and can adapt to various complex outdoor environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a schematic structural diagram of a driving mechanism provided in an embodiment of the present application when it is installed on a shielding member;

[0025] FIG2 is a schematic structural diagram of a shielding member after being deployed by a driving mechanism according to an embodiment of the present application;

[0026] FIG3 is a schematic structural diagram of a shielding member after being retracted by a driving mechanism according to an embodiment of the present application;

[0027] FIG4 is a partial enlarged view of point A in FIG2;

[0028] FIG5 is a schematic structural diagram of a guide device provided in one embodiment of the present application;

[0029] FIG6 is a partial enlarged view of FIG6B;

[0030] FIG7 is a schematic structural diagram of a guide device provided in one embodiment of the present application;

[0031] FIG8 is a schematic structural diagram of an angle adjustment device provided in one embodiment of the present application;

[0032] FIG9 is a schematic structural diagram of an angle adjustment device provided in one embodiment of the present application;

[0033] FIG10 is a partial enlarged view of point D in FIG9;

[0034] FIG11 is a schematic diagram of the structure of a driving component of an angle adjustment device provided in one embodiment of the present application;

[0035] FIG12 is a schematic diagram of the structure of a driving assembly of an angle adjustment device provided in one embodiment of the present application; Description of reference numerals:

[0036] a. Driving mechanism; b. Object;

[0037] 1. Screw; 2. Driving pulley; 3. Transmission member; 5. Guide device; 6. Angle adjustment device;

[0038] 11. External thread groove; 11a. Small pitch area; 11b. Large pitch area;

[0039] 31. First reinforcement rib;

[0040] 51. Guide rail; 52. Guide pulley; 53. Housing;

[0041] 61. Central rotating shaft; 62. First docking portion; 63. Second docking portion; 64. Adjusting drive device;

[0042] 631, docking seat; 632, docking shaft; 633, docking drive handle; 634, connecting rod; 635, first drive slider;

[0043] 6311, docking slot;

[0044] 621, docking piece; 622, docking roller;

[0045] 641, adjusting driving handle; 642, driving shaft; 643, driving assembly; 644, second driving slider; 645, guide assembly;

[0046] 6431, driving screw; 6432, driving nut; 6433, driving bump;

[0047] 6451, guide protrusion; 6452, guide plate; 6453, guide groove; DETAILED DESCRIPTION

[0048] The terms used in the implementation section of this application are only used to explain the specific embodiments of this application and are not intended to limit this application. The implementation of the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0049] As shown in FIG1 , the driving mechanism a for driving the object b to fold or unfold in this embodiment can be applied to blinds, sunshades, retractable doors, etc., and the embodiment of the present application is not limited to this, nor is it limited to the application of the above examples.

[0050] FIG2 is a schematic diagram of the structure of the object b in the unfolded state in this embodiment;

[0051] FIG3 is a schematic diagram of the structure of the object b in the embodiment when it is in a folded state;

[0052] The following is an example of a blind:

[0053] It should be noted that in the embodiment of the present application, the driving mechanism a in the Venetian blinds can be set to at least one, two, three or more. For example, the driving mechanism a in Figure 1 is set to two, which are respectively arranged on both sides of the Venetian blinds to drive the blinds of the Venetian blinds to retract or expand.

[0054] As shown in Figure 4, the driving mechanism a of this embodiment includes a screw 1, a driving pulley 2, a transmission member 3 and a first driving device. One end of the transmission member 3 is rotatably connected to one side of the object b, and the other end of the transmission member 3 is rotatably connected to the driving pulley 2. The outer periphery of the screw 1 is provided with at least two sections of external thread grooves 11 with different pitches. The driving pulley 2 is arranged in the external thread groove 11. The first driving device drives the screw 1 to rotate. The screw 1 drives the driving pulley 2 to move along the external thread groove 11 through the external thread groove 11. The external thread groove 11 includes a small pitch area 11a and a large pitch area 11b. When the driving pulley 2 drives the object b to move from the small pitch area 11a to the large pitch area 11b, the object b performs an expansion movement. When the driving pulley 2 drives the animal b to move from the large pitch area 11b to the small pitch area 11a, the object b performs a retraction movement.

[0055] The first driving device may be, for example, a manual device, an electric motor, or a pneumatic device, etc. The embodiments of the present application are not limited to this, nor are they limited to the above examples.

[0056] Manual devices are manually operated and are usually actuated by a manual knob, handle or lever.

[0057] The working principle of this embodiment is:

[0058] When the present application unfolds the object b in the folded state to the unfolded state, the first driving device first drives the screw 1 to rotate. At this time, the driving pulley 2 in the small pitch area 11a drives the object b to move along the external thread groove 11 toward the large pitch area 11b, so that the object b unfolds. When the object b in the unfolded state needs to be folded together, the first driving device also drives the screw 1 to rotate in the opposite direction, so that the driving pulley 2 in the large pitch area 11b drives the object b to move along the external thread groove 11 toward the small pitch area 11a, thereby achieving the folding of the object b. Compared with the prior art, the advantages of the present application are: (1) The present application adopts the method of the screw 1 and the external thread groove 11, which can provide higher precision and controllability. The external thread groove 11 with different pitches can achieve precise motion control, allowing the object b to be smoothly unfolded and folded. (2) Compared with the sprocket chain system, the chain needs to be lubricated and replaced regularly, which is not suitable for complex outdoor environments. The present application requires less maintenance, does not require lubrication, and can adapt to various complex outdoor environments.

[0059] As shown in FIG4 , the transmission member 3 in this embodiment is provided with first reinforcing ribs 31. The reinforcing ribs increase the rigidity and stability of the transmission member 3, particularly during long-distance transmission or high-load conditions. This helps reduce bending and deformation of the transmission member 3, ensuring a more stable and controllable motion process.

[0060] As shown in Figures 5 and 6, in this embodiment, the driving mechanism a also includes a guide device 5, which is used to assist the object b in guiding during the folding or unfolding movement. The guide device 5 includes a guide rail 51 and a guide pulley 52. ​​The guide pulley 52 is rotatably mounted on the transmission member 3, and the guide rail 51 is mounted on the outer shell 53.

[0061] As shown in Figure 7, three guide pulleys 52 are provided and arranged in a triangular pattern. The guide pulleys 52 can move relative to each other along the guide rail 51. The guide device 5 can ensure that the object b maintains a stable trajectory during the folding or unfolding movement. The cooperation between the guide pulley 52 and the rail can effectively reduce swaying and shaking, ensuring smooth movement. The three guide pulleys 52 are arranged in a triangular pattern to provide greater stability. They can balance the forces in all directions, prevent the guide pulley 52 from tilting or shaking during movement, and ensure that the guided object moves smoothly. The three guide pulleys 52 disperse the load so that it is evenly distributed on the guided object. This can reduce the load on a single guide pulley 52 and extend the life of the pulley and the guide device 5.

[0062] As shown in FIG8 to FIG9 , in this embodiment, the driving mechanism a further includes an angle adjustment device 6 , which is used to adjust the angle of the object b.

[0063] As shown in Figure 9, the angle adjustment device 6 includes a central rotating shaft 61, a first docking part 62, a second docking part 63 and an adjusting drive device 64. The central rotating shaft 61 is rotatably installed on the transmission member 3. One end of the central rotating shaft 61 is connected to the object b, and the other end of the central rotating shaft 61 is connected to the first docking part 62. The driving pulley 2 drives the first docking part 62 to move to the second docking part 63 through the transmission member 3. The first docking part 62 and the second docking part 63 are docked with each other. The adjusting drive device 64 can drive the second docking part 63 to rotate. The second docking part 63 drives the first docking part 62 to rotate. The first docking part 62 drives the object b to rotate through the central rotating shaft 61.

[0064] In this embodiment, the angle of the object b can be precisely adjusted by the angle adjustment device 6 to suit different needs and working scenarios. This can be used to adjust the direction, angle or degree of shading of light.

[0065] As shown in Figure 10, in this embodiment, the second docking portion 63 includes a docking seat 631, a docking shaft 632, a docking drive handle 633, and a connecting rod 634. One end of the docking shaft 632 is connected to the docking seat 631, and the other end of the docking shaft 632 is connected to the docking shaft 632. A first drive slider 635 is rotatably mounted near at least one end of the docking shaft 632. The first drive slider 635 is slidably mounted on the connecting rod 634. The adjustment drive device 64 can drive the connecting rod 634 to move up and down. The connecting rod 634 can drive the first drive slider 635 to rotate the docking drive handle 633, and the docking drive handle 633 can rotate the docking shaft 632 and the docking seat 631. In this embodiment, the connecting rod 634 mechanism can provide precise angle adjustment, ensuring that the object B is adjusted to the desired angle. The connecting rod 634 mechanism can achieve smooth angle adjustment movement, reducing instability and vibration. This helps maintain the smooth movement of the object B and avoid unexpected shaking.

[0066] In this embodiment, two connecting rods 634 are provided, arranged in parallel, and have an I-shaped cross-section. The I-shaped cross-section of connecting rod 634 provides high bending stiffness and resistance between two parallel axes. This enables connecting rod 634 to withstand large forces and torques without excessive bending or deformation.

[0067] As shown in FIG. 11 , in this embodiment, a docking groove 6311 is provided on the docking seat 631 corresponding to the first docking portion 62 .

[0068] In this embodiment, the first docking portion 62 can be inserted into the docking slot 6311 to mate with the second docking portion 63. The plug-in design allows for relatively easy insertion and removal of the first docking portion 62, which facilitates maintenance, replacement, or upgrades of the system. This removability can reduce the cost and workload of repairs and maintenance.

[0069] As shown in Figure 10, in this embodiment, the first docking part 62 includes a docking piece 621 and a docking roller 622. One side of the docking piece 621 is installed on the central rotating shaft 61, and the docking rollers 622 are symmetrically arranged on the other side of the docking piece 621. The docking rollers 622 can slide into the docking groove 6311 of the docking seat 631.

[0070] The sliding mechanism of the docking roller 622 provides smooth movement, reducing friction and resistance. This helps ensure that the angle adjustment of object B is smooth, avoiding unnecessary vibration or frictional losses. The sliding mechanism of the docking roller 622 provides smooth movement, reducing friction and resistance. This helps ensure that the angle adjustment of object B is smooth, avoiding unnecessary vibration or frictional losses. Rollers generally have good wear resistance, so they can maintain efficiency over long periods of use.

[0071] As shown in Figure 11, in this embodiment, the adjusting drive device 64 includes an adjusting drive handle 641, a driving shaft 642 and a driving assembly 643. The adjusting drive handle 641 is installed on the driving shaft 642. The adjusting drive handle 641 is connected to the connecting rod 634 through the second driving slider 644. The driving assembly 643 can drive the adjusting drive handle 641 to rotate around the driving shaft 642. The adjusting drive handle 641 drives the connecting rod 634 to perform lifting movements through the second driving slider 644.

[0072] As shown in Figure 12, in this embodiment, the driving assembly 643 includes a driving screw 6431, a driving nut 6432 and a driving protrusion 6433. The driving protrusion 6433 is installed on the driving nut 6432, and the driving nut 6432 is installed on the driving screw 6431. The driving screw 6431 can drive the driving nut 6432 to drive the driving protrusion 6433 to perform lifting motion. The raised portion of the driving protrusion 6433 cooperates with the driving groove of the adjusting driving handle 641. The driving protrusion 6433 performs lifting motion in the driving groove, thereby driving the adjusting driving handle 641 to rotate around the driving shaft 642.

[0073] In this embodiment, the device that drives the screw rod 6431 to rotate can be a manual device, an electric motor, a pneumatic device, etc. The embodiment of the present application is not limited to this, nor is it limited to the above examples.

[0074] As shown in Figure 11, in this embodiment, the drive assembly 643 also includes a guide assembly 645, which includes a guide protrusion 6451 and a guide plate 6452. The guide plate 6452 is provided with a guide groove 6453. The guide protrusion 6451 is mounted on the drive nut 6432. The raised portion of the guide protrusion 6451 cooperates with the guide groove 6453 to guide the lifting and lowering of the drive protrusion 6433. The design of the guide protrusion 6451 and the guide groove 6453 provides stable guidance, preventing the drive protrusion 6433 from shaking or deviating from its trajectory during the lifting process. This helps maintain the stability and performance of the system.

[0075] In the description of the embodiments of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to a fixed connection, an indirect connection via an intermediate medium, internal communication between two components, or an interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of this application based on specific circumstances.

[0076] In the embodiments of the present application, any device or element referred to or implied must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the embodiments of the present application. In the description of the embodiments of the present application, the meaning of "plurality" is two or more, unless otherwise specifically specified.

[0077] The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the embodiments of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way are interchangeable under appropriate circumstances, so that the embodiments of the present application described herein, for example, can be implemented in orders other than those illustrated or described herein. In addition, the terms "may include" and "have" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or inherent to these processes, methods, products or apparatus.

[0078] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they may modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, such modifications or replacements do not deviate from the essence of the corresponding technical solutions within the scope of the various embodiments of this application.

Claims

1. A driving mechanism for driving an object to fold or unfold, characterized in that: It includes a screw rod, a driving pulley, a transmission member and a first driving device, one end of the transmission member is connected to an object, and the other end of the transmission member is connected to the driving pulley. The outer circumference of the screw rod is provided with at least two sections of external thread grooves with different pitches, and the driving pulley is arranged in the external thread groove. The first driving device drives the screw rod to rotate, and the screw rod drives the driving pulley to move along the external thread groove through the external thread groove. The external thread groove includes a small pitch area and a large pitch area. When the driving pulley moves from the small pitch area to the large pitch area, the object performs an expansion movement, and when the driving pulley moves from the large pitch area to the small pitch area, the object performs a retraction movement.

2. A driving mechanism for driving an object to collapse or expand according to claim 1, characterized in that: The driving mechanism also includes a guiding device, which is used to assist in guiding the object during the folding or unfolding movement. The guiding device includes a guiding rail and a guiding pulley. The guiding pulley is rotatably mounted on the transmission member, and the guiding pulley can move relatively along the guiding rail.

3. A driving mechanism for driving an object to collapse or expand according to claim 1, characterized in that: The driving mechanism also includes an angle adjustment device, which is used to adjust the angle of the object. The angle adjustment device includes a central shaft, a first docking part, a second docking part and an adjustment drive device. The central shaft can be rotatably installed on the transmission member. One end of the central shaft is connected to the object, and the other end of the central shaft is connected to the first docking part. The driving pulley drives the first docking part to move to the second docking part through the transmission member. The first docking part and the second docking part are docked with each other. The adjustment drive device can drive the second docking part to perform rotational motion, and the second docking part drives the first docking part to perform rotational motion. The first docking part drives the object to perform rotational motion through the central shaft.

4. A driving mechanism for driving an object to collapse or expand according to claim 3, characterized in that: The second docking part includes a docking seat, a docking shaft, a docking drive handle and a connecting rod, one end of the docking shaft is connected to the docking seat, and the other end of the docking shaft is connected to the docking shaft. A first driving slider is rotatably installed near at least one end of the docking shaft, and the first driving slider is slidably installed on the connecting rod. The adjusting drive device can drive the first driving slider through the connecting rod to drive the docking drive handle to rotate, and the docking drive handle drives the docking shaft and the docking seat to rotate.

5. A driving mechanism for driving an object to collapse or expand according to claim 4, characterized in that: The connecting rods are provided with two.

6. A driving mechanism for driving an object to collapse or expand according to claim 4, characterized in that: The docking seat is provided with a docking groove corresponding to the first docking portion.

7. A driving mechanism for driving an object to collapse or expand according to claim 6, characterized in that: The first docking portion can be inserted into the docking groove and matched with the second docking portion.

8. The driving mechanism for driving an object to collapse or expand according to claim 6, characterized in that: The first docking portion includes a docking piece and a docking roller. One side of the docking piece is installed on the central shaft, and the docking rollers are symmetrically arranged on the other side of the docking piece. The docking rollers can slide into the docking grooves of the docking seat.

9. The driving mechanism for driving an object to collapse or expand according to claim 4, characterized in that: The adjusting drive device includes an adjusting drive handle, a driving shaft and a driving assembly. The adjusting drive handle is installed on the driving shaft. The adjusting drive handle is connected to the connecting rod through a second driving slider. The driving assembly can drive the adjusting drive handle to rotate around the driving shaft. The adjusting drive handle drives the connecting rod to perform lifting and lowering movements through the second driving slider.

10. A driving mechanism for driving an object to collapse or expand according to claim 9, characterized in that: The driving assembly includes a driving screw, a driving nut and a driving protrusion, wherein the driving protrusion is mounted on the driving nut, and the driving nut is mounted on the driving screw. The driving screw can drive the driving nut to drive the driving protrusion to perform lifting motion. The raised portion of the driving protrusion cooperates with the driving slot of the adjusting driving handle. The driving protrusion performs lifting motion in the driving slot, thereby driving the adjusting driving handle to perform rotational motion around the driving shaft.

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