Electric cable drive mechanism with self-return function

Abstract

The present invention provides an electric cable drive mechanism with a self-returning function, comprising a housing assembly, a motor, a three-stage transmission mechanism and a multifunctional nut, wherein the three-stage transmission mechanism comprises a coil spring assembly, the motor is fixed to the housing assembly, and the three-stage transmission mechanism and the multifunctional nut are installed in the housing assembly; the multifunctional nut comprises two cable mounting grooves and is connected to the motor through the three-stage transmission mechanism. The electric cable drive mechanism with a self-returning function of the present invention uses a three-stage transmission system, which has a greater output force than a two-stage transmission; the split multifunctional lead screw is easy to install, preventing the lead screw from being scratched by the coil spring during assembly, and solving the problem of abnormal noise generated during the coil spring installation process.

Description

Technical Field

[0001] The invention relates to the field of electric cable drive mechanisms, and in particular to an electric cable drive mechanism with a self-returning function. Background Art

[0002] The commonly used transmission form of the existing electric cable drive mechanism is: the motor drives the two-stage transmission system, and the transmission system consists of a primary gear transmission and a primary screw nut transmission; in this case, the primary gear and the screw nut can be manufactured using different processes, such as (1) one-piece injection molded plastic parts; (2) the screw is metal and the gear is circumferentially coated with plastic; the output force of the two-stage transmission is usually relatively small. If a larger output force is required, the strength of this method is usually not enough. When the coil spring is installed into the one-piece screw, due to the limitation of the space arrangement, it needs to pass axially through a relatively long screw, which may scratch the screw and cause abnormal noise. Summary of the invention

[0003] In view of the deficiencies in the above-mentioned prior art, the present invention provides an electric cable drive mechanism with a self-return function, which uses a three-stage transmission system and has a greater output force than a two-stage transmission. The split multifunctional screw rod is easy to install and can prevent the installation of the coil spring from scratching the screw rod during the assembly process, thereby solving the problem of abnormal noise generated during the installation of the coil spring.

[0004] In order to achieve the above-mentioned objectives, the present invention provides an electric cable drive mechanism with a self-return function, comprising a housing assembly, a motor, a three-stage transmission mechanism and a multifunctional nut, the three-stage transmission mechanism comprising a coil spring assembly, the motor being fixed to the housing assembly, the three-stage transmission mechanism and the multifunctional nut being installed in the housing assembly; the multifunctional nut comprising two cable mounting grooves and being connected to the motor through the three-stage transmission mechanism.

[0005] Preferably, the three-stage transmission mechanism includes a multifunctional screw rod, the coil spring assembly and a three-stage gear; the multifunctional screw rod includes a spline and an external threaded section, and a shoulder is formed at both ends of the multifunctional screw rod respectively, the housing assembly forms a U-shaped groove that cooperates with the shoulder, and a groove is formed on the outside of the spline; the coil spring assembly and the three-stage gear are sleeved on the outside of the spline, and a connecting part that cooperates with the spline is formed inside the three-stage gear and is sleeved on the outside of the spline through the connecting part, and a convex rib that cooperates with the groove is formed on the outer end of the three-stage gear; the coil spring assembly includes a coil spring and a cover, the inner end of the coil spring is limited by the spline, and the outer end of the coil spring is connected to the cover.

[0006] Preferably, the coil spring assembly is arranged between the three-stage gear and the external thread segment, or the coil spring assembly, the three-stage gear and the external thread segment are arranged in sequence.

[0007] Preferably, the three-stage transmission mechanism also includes an input gear and a duplex gear; the input gear is connected to the output shaft of the motor, and the duplex gear is transmission-connected to the input gear; the three-stage gear is transmission-connected to the duplex gear.

[0008] Preferably, the multifunctional nut comprises a non-self-locking internal threaded hole, a plurality of guide strips, two limit planes and the cable mounting groove; the non-self-locking internal threaded hole is formed in the middle part of the multifunctional nut and is screwed to the external threaded section of the multifunctional screw rod through the non-self-locking internal threaded hole; the guide strip is formed on the upper and lower surfaces of the multifunctional nut and extends along the axial direction of the non-self-locking internal threaded hole, and the shell assembly forms a guide groove cooperating with the guide strip; the top surface and the bottom surface of the multifunctional nut respectively form a limit plane, and the shell assembly limits the limit plane.

[0009] Preferably, the cable installation groove is formed on both sides of the multifunctional nut, and the cable installation groove includes a structure to prevent the cable head from sliding out.

[0010] Preferably, the cable installation groove comprises an outer section and an inner section, and the width of the outer section is smaller than the width of the inner section.

[0011] Preferably, the multifunctional nut is provided with two bosses on the side walls at both ends of the non-self-locking internal threaded hole, and rubber pads are sleeved on the bosses.

[0012] Preferably, it also includes a rubber sleeve, which is arranged outside the multifunctional nut.

[0013] Preferably, it also includes a connector and a connecting terminal; the shell assembly includes a cover plate and a box body, and the cover plate and the box body cooperate to form a connector installation space and a motor installation space; the connector is arranged in the connector installation space, and the motor is arranged in the motor installation space; the first end of the connecting terminal is connected to the connector by snap-on connection, and the second end of the connecting terminal forms a bending portion; the end of the motor forms a positioning hole that cooperates with the bending portion, and the bending portion is inserted into the positioning hole.

[0014] Preferably, the housing assembly comprises a cover plate and a box body, the box body forms a motor connection port, and the motor is screwed to the motor connection port.

[0015] The present invention adopts the above technical solution, so it has the following beneficial effects:

[0016] The three-stage transmission mechanism has a greater output force than the two-stage transmission. Different forces can be output by using motors with different powers but sharing the transmission parts. The motor with relatively large torque is reduced by three stages, and the force converted to the screw output is higher. The split multifunctional screw is easy to install, which prevents the installation of the coil spring from scratching the screw during assembly and solves the problem of abnormal noise during the installation of the coil spring. The motor power and the appearance connection interface are different. By using the same transmission parts, selecting two motors with different performances, and adapting to different interfaces, two different segmented forces can be output to achieve the optimal solution of cost and performance. The multifunctional nut has a structure to prevent the cable head from sliding out. The coil spring assembly realizes the reverse drive of the multifunctional nut to automatically return to the initial position after the motion system action is completed; the rubber pad can reduce the impact sound between the multifunctional nut and the box when the multifunctional nut runs to the blocking point. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an exploded view of the electric cable driving mechanism with self-return function according to the first embodiment of the present invention;

[0018] Figure 2 It is a structural schematic diagram of a multifunctional lead screw, a coil spring assembly and a three-stage gear according to the first embodiment of the present invention;

[0019] Figure 3 is a cross-sectional view of a three-stage gear according to the first embodiment of the present invention;

[0020] Figure 4 This is a schematic structural diagram of a multifunctional nut according to Embodiment 1 of the present invention;

[0021] Figure 5 This is a first operating condition diagram of the first embodiment of the present invention;

[0022] Figure 6 This is a second operating condition diagram of the first embodiment of the present invention;

[0023] Figure 7 This is a third operating condition diagram of the first embodiment of the present invention;

[0024] Figure 8 It is an exploded view of an electric cable driving mechanism with a self-returning function according to the second embodiment of the present invention;

[0025] Fig. 9 This is a schematic diagram of the structure of the first embodiment of the present invention when a helical gear is used. DETAILED DESCRIPTION

[0026] According to the attached figure Figures 1 to 8 , give the preferred embodiments of the present invention, and describe them in detail so that the functions and features of the present invention can be better understood.

[0027] See also Figure 1 to Figure 7An electric cable drive mechanism with a self-returning function according to an embodiment of the present invention comprises a housing assembly 1, a motor 2, a three-stage transmission mechanism 3 and a multifunctional nut 4, wherein the three-stage transmission mechanism 3 comprises a coil spring assembly 32, the motor 2 is fixed to the housing assembly 1, and the three-stage transmission mechanism 3 and the multifunctional nut 4 are installed in the housing assembly 1; the multifunctional nut 4 comprises two cable mounting grooves 41 and is connected to the motor 2 through the three-stage transmission mechanism 3.

[0028] See also Figure 1 to Figure 3 The three-stage transmission mechanism 3 includes a multifunctional screw rod 31, a coil spring assembly 32 and a three-stage gear 33; the multifunctional screw rod 31 includes a spline 311 and an external thread section 312, and a shoulder 313 is formed at both ends of the multifunctional screw rod 31, and the housing assembly 1 forms a U-shaped groove matched with the shoulder 313, and a groove 314 is formed on the outer side of the spline 311; the coil spring assembly 32 and the three-stage gear 33 are sleeved outside the spline 311, and the three-stage gear 33 A connecting portion 331 is formed inside and cooperates with the spline 311, and is sleeved on the outside of the spline 311 through the connecting portion 331. A convex rib 332 is formed on the outer end of the three-stage gear 33 to cooperate with the groove 314 to achieve axial limitation. The coil spring assembly 32 includes a coil spring 321 and a cover 322. The inner end of the coil spring 321 cooperates with the spline 311 for limitation, and the outer end of the coil spring 321 is connected to the cover 322 to achieve driving and reverse driving of the torque of the coil spring 321.

[0029] Figure 2 In the figure, the coil spring assembly 32 is located between the third-stage gear 33 and the external thread section 312. The assembly size of this solution is relatively small. The positions of the coil spring assembly 32 and the third-stage gear 33 can also be interchanged to realize the function of the assembly, but the overall size is enlarged.

[0030] See also Figure 1 and Figure 5 The three-stage transmission mechanism 3 also includes an input gear 34 and a duplex gear 35; the input gear 34 is connected to the output shaft of the motor 2, and the duplex gear 35 is transmission-connected to the input gear 34; the three-stage gear 33 is transmission-connected to the duplex gear 35.

[0031] Fig. 9 The middle double gear 35 is a helical gear structure, and the third-stage gear 33 can also be set as a helical gear.

[0032] See also Figure 1 and Figure 4The multifunctional nut 4 includes a non-self-locking internal threaded hole 42, a plurality of guide strips 43, two limiting planes 44 and a cable mounting groove 41; a non-self-locking internal threaded hole 42 is formed in the middle of the multifunctional nut 4 and is screwed to the external threaded section 312 of the multifunctional screw rod 31 through the non-self-locking internal threaded hole 42; the guide strip 43 is formed on the upper and lower surfaces of the multifunctional nut 4 and extends along the axial direction of the non-self-locking internal threaded hole 42, and the housing assembly 1 forms a guide groove that cooperates with the guide strip 43; the top surface and the bottom surface of the multifunctional nut 4 respectively form a limiting plane 44, and the housing assembly 1 limits the limiting plane 44.

[0033] The guide bar 43 cooperates with the box body 12 to prevent the multifunctional nut 4 from rotating around the multifunctional screw rod 31 (the screw rod 31 is rotating), and guides the multifunctional nut 4 to move axially along the multifunctional screw rod 31. The two limiting planes 44 cooperate with the box body 12 (and the box cover 11) to prevent the multifunctional nut 4 from moving in the height direction. The two cable installation grooves 41 can be installed with two different forms of cable heads, a rectangular parallelepiped and a cylindrical one, according to the size relationship.

[0034] The cable installation groove 41 is formed on both sides of the multifunctional nut 4, and the cable installation groove 41 includes a cable head anti-slip structure. The cable installation groove 41 includes an outer section and an inner section, and the width of the outer section is smaller than the width of the inner section. The cable head installed in the cable installation groove 41 is prevented from slipping out.

[0035] During assembly, the cable head needs to be assembled at a certain angle to the xy plane; the multifunctional nut 4 is displaced along the axial direction of the multifunctional screw rod 31, which can ensure that the cable head will not be separated from the cable installation groove 41 during normal operation;

[0036] The cable installation groove 41 can be made into different shapes, such as being compatible with rectangular cable heads and cylindrical cable heads, and has strong adaptability.

[0037] The multifunctional nut 4 is provided with two bosses on the side walls at both ends of the non-self-locking internal threaded hole 42 , and rubber pads 45 are sleeved on the bosses for absorbing energy and reducing noise.

[0038] The multifunctional nut 4 also includes a rubber sleeve 46 , which is sleeved on the outside of the multifunctional nut 4 .

[0039] See also Figure 1 and Figure 5 , and also includes a connector 5 and a connecting terminal 6; the housing assembly 1 includes a cover plate 11 and a box body 12, and the cover plate 11 and the box body 12 cooperate to form a connector installation space and a motor installation space; the connector 5 is arranged in the connector installation space, and the motor 2 is arranged in the motor installation space; the first end of the connecting terminal 6 is snap-connected with the connector 5, and the second end of the connecting terminal 6 forms a bending portion; the end of the motor 2 forms a positioning hole that cooperates with the bending portion, and the bending portion is inserted into the positioning hole.

[0040] The motor 2 of this embodiment adopts a low-torque motor with a torque range of 0 to 0.05 Nm. This is just an example and does not limit the low-torque motor.

[0041] An electric cable drive mechanism with a self-returning function according to an embodiment of the present invention has the following working process:

[0042] See also Figure 1 and Figure 5 , the initial state of the system:

[0043] The coil spring 321 is pre-tightened by about one turn in the assembly, and the axial force generated by the pre-tightening torque on the multi-function screw rod 31 can make the multi-function nut 4 always at the farthest end, preventing the sound caused by the axial gap, and can ensure that the multi-function nut 4 can return to the farthest end at any time when the motor 2 is powered on, preventing unlocking of the external mechanism;

[0044] See also Figure 1 , Figure 2 and Figure 6 , power-on status:

[0045] When powered on, the motor 2 drives the input gear 34 to rotate counterclockwise, the double gear 35 to rotate clockwise, and drives the third-stage gear 33 to rotate counterclockwise;

[0046] The multifunctional screw rod 31 rotates counterclockwise, and the inner ring of the coil spring 321 is tightened through the spline 311 feature at the end of the multifunctional screw rod 31, and the multifunctional nut 4 is driven to move forward along the guide feature of the box body 12, and the coil spring is energized at this time;

[0047] See also Figure 1 and Figure 7 , extreme position (power on):

[0048] The motor 2 is powered on, driving the multifunctional nut 4 to move to the limit position (the multifunctional nut 4 contacts the baffle of the box body 12, thereby compressing the rubber sleeve 46), and cannot continue to move to the left;

[0049] The motor 2 stops rotating and the coil spring 321 is tightened to the limit state;

[0050] Limit position (power off):

[0051] After the motor 2 is powered off, the coil spring 321 starts to release energy, reversely driving the multifunctional screw rod 31 to rotate clockwise, thereby driving the multifunctional nut 4 assembly to move backward along the guide groove of the box body 12;

[0052] The multifunctional screw rod 31 drives the three-stage gear 33 to drive the double gear 35 to rotate counterclockwise;

[0053] The double gear 35 drives the input gear 34 to rotate clockwise.

[0054] (The screw rod rotates leftwards and the motor rotates counterclockwise for illustration only; if the screw rod's rotation direction is changed, such as the screw rod rotates rightwards and the motor rotates clockwise, the assembly function can also be achieved)

[0055] See also Figure 1 and Figure 5 , the coil spring 321 is driven in reverse to the initial state:

[0056] After the motor 2 is powered off, the coil spring 321 drives the multifunctional screw rod 31 to reverse, and the multifunctional nut 4 moves backward along the guide groove of the box body 12 to the baffle position on the right side of the box body 12. After compressing the rubber sleeve 46 to the limit, the coil spring 321 stops releasing energy; at this time, since the coil spring 321 still has pre-tightening turns and pre-tightening torque initially, the multifunctional nut 4 stops at the rightmost end of the box body 12, and the system stops running.

[0057] See also Figure 8 The electric cable drive mechanism with a self-returning function according to the embodiment of the present invention has a structure that is basically the same as that of the first embodiment, except that the housing 12 forms a motor connection port, and the motor 2 is screwed to the motor connection port.

[0058] In this embodiment, the motor adopts a high torque motor with a torque greater than 0.05 Nm. The motor is axially fixed to the box body 12 by screws through two screw holes on the end surface. This method can greatly reduce costs.

[0059] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. An electric cable drive mechanism with self-return function, characterized in that: It comprises a housing assembly, a motor, a three-stage transmission mechanism and a multifunctional nut, wherein the motor is fixed to the housing assembly, the three-stage transmission mechanism and the multifunctional nut are installed in the housing assembly; the multifunctional nut comprises two cable installation grooves and is connected to the motor through the three-stage transmission mechanism; The three-stage transmission mechanism includes a multifunctional screw rod, a coil spring assembly and a three-stage gear; the multifunctional screw rod includes a spline and an external thread section, and two ends of the multifunctional screw rod form a shaft shoulder respectively, the housing assembly forms a U-shaped groove matched with the shaft shoulder, and the outer side of the spline forms a groove; the coil spring assembly and the three-stage gear are sleeved outside the spline, and a connecting part matched with the spline is formed inside the three-stage gear and sleeved outside the spline through the connecting part, and a convex rib matched with the groove is formed on the outer end of the three-stage gear; the coil spring assembly includes a coil spring and a cover, the inner end of the coil spring is limited by the spline, and the outer end of the coil spring is connected to the cover; The coil spring assembly is arranged between the three-stage gear and the external thread segment, or the coil spring assembly, the three-stage gear and the external thread segment are arranged in sequence; The multifunctional nut comprises a non-self-locking internal threaded hole, a plurality of guide strips, two limit planes and the cable mounting groove; the non-self-locking internal threaded hole is formed in the middle part of the multifunctional nut and is screwed to the external threaded section of the multifunctional screw rod through the non-self-locking internal threaded hole; the guide strips are formed on the upper and lower surfaces of the multifunctional nut and extend along the axial direction of the non-self-locking internal threaded hole, and the shell assembly forms a guide groove cooperating with the guide strip; the top surface and the bottom surface of the multifunctional nut respectively form a limit plane, and the shell assembly limits the limit plane.

2. The electric cable drive mechanism with self-return function according to claim 1, characterized in that: The three-stage transmission mechanism also includes an input gear and a duplex gear; the input gear is connected to the output shaft of the motor, and the duplex gear is transmission-connected to the input gear; the three-stage gear is transmission-connected to the duplex gear.

3. The electric cable drive mechanism with self-return function according to claim 2, characterized in that: The cable installation groove is formed on both sides of the multifunctional nut, and the cable installation groove includes a structure to prevent the cable head from sliding out.

4. The electric cable drive mechanism with self-return function according to claim 1, characterized in that: The cable installation groove includes an outer section and an inner section, and the width of the outer section is smaller than the width of the inner section.

5. The electric cable drive mechanism with self-returning function according to claim 3, characterized in that: The multifunctional nut is provided with two bosses on the side walls at both ends of the non-self-locking internal threaded hole, and rubber pads are sleeved on the bosses.

6. The electric cable drive mechanism with self-return function according to claim 4, characterized in that: It also includes a rubber sleeve, which is sleeved outside the multifunctional nut.

7. The electric cable drive mechanism with self-return function according to claim 4, characterized in that: It also includes a connector and a connecting terminal; the shell assembly includes a cover plate and a box body, the cover plate and the box body cooperate to form a connector installation space and a motor installation space; the connector is arranged in the connector installation space, and the motor is arranged in the motor installation space; the first end of the connecting terminal is connected to the connector by snap-fitting, and the second end of the connecting terminal forms a bending portion; the end of the motor forms a positioning hole that cooperates with the bending portion, and the bending portion is inserted into the positioning hole.

8. The electric cable drive mechanism with self-return function according to claim 4, characterized in that: The housing assembly includes a cover plate and a box body, the box body forms a motor connection port, and the motor is screwed to the motor connection port.

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