Electric push rod with clutch function

Abstract

An electric push rod with a clutch function comprises a bottom shell and a surface cover, a containing cavity is formed in the bottom shell, a reduction gear set driven by a motor is installed in the containing cavity, a driving gear is installed on an output shaft of the reduction gear set, and the driving gear is meshed with a driven gear arranged on the cylindrical surface of a screw in a sleeving mode and drives the driven gear to rotate; the screw rod is installed in the bottom shell in a rotating mode and extends out of the bottom shell, the screw rod is further sleeved with a retainer in a rotating mode, a plurality of guide grooves are formed in the retainer in a radial extending mode, clutch shafts are installed in the guide grooves, and the clutch shafts are pushed by a spring to move in the radial direction. The clutch device has the advantages that the unique clutch structure design is adopted, the motor can be automatically disengaged from the clutch when not working, and therefore the screw rod is allowed to rotate freely. In the state, the internal gear and the motor do not rotate along with the rotation of the screw rod, which means that a user can push the nut to freely move in the axial direction of the screw rod through manual operation.

Description

Technical Field

[0001] The utility model relates to the technical field of electric push rods, in particular to an electric push rod with a clutch function. Background Art

[0002] As an important mechanical actuator, electric linear actuators are widely used in various products requiring linear thrust, such as furniture, medical beds, electric sofas, and industrial machinery. Electric linear actuators are typically driven by a motor, which converts the motor's rotational motion into linear motion of a sleeve assembly through an internal transmission component, thereby achieving the actuator's telescopic function.

[0003] In traditional electric linear actuator designs, the sleeve assembly is capable of self-extension to meet the needs of various operating conditions. To quickly connect and disconnect the motor-driven sleeve assembly and transmission assembly, a clutch is typically installed between them. This clutch serves as a link for power transmission, quickly engaging the transmission assembly and sleeve assembly when needed and disconnecting power when necessary. This allows the device to be manually operated during power outages. Alternatively, if the user is unaware of the electric opening and closing function and chooses to manually open and close the actuator, the power connection is disconnected to prevent damage.

[0004] However, existing electric actuator clutches on the market often experience unsmooth operation during power engagement and disconnection. This is especially true under high loads or high-frequency operation, where the clutch engagement and disconnection may experience jitter or delay, leading to overall system instability. This unsmoothness not only impacts the actuator's performance but can also cause additional mechanical stress on the motor and transmission components, shortening the system's service life.

[0005] Furthermore, the complex structure of the clutch and the long power transmission path affect transmission efficiency. During the power connection process, some mechanical energy may be lost due to factors such as friction and backlash, failing to effectively convert it into linear motion of the push rod, thus affecting the efficiency of the entire system. Therefore, further improvements are necessary. Utility Model Content

[0006] The purpose of the utility model is to overcome the shortcomings of the prior art and provide an electric push rod with a clutch function which has a simple structure, is easy to use, has high power transmission efficiency and a long service life.

[0007] The purpose of the utility model is achieved in the following way: an electric push rod with a clutch function, which includes a bottom shell and a cover, a receiving cavity is provided in the bottom shell, a reduction gear set driven by a motor is installed in the receiving cavity, a driving gear is installed on the output shaft of the reduction gear set, and the driving gear meshes with a driven gear sleeved on the cylindrical surface of the screw and drives it to rotate;

[0008] The screw is rotatably mounted in the bottom shell and extends out of the bottom shell. A retainer is rotatably mounted on the outside of the screw. A plurality of guide grooves are radially extended on the retainer. A clutch shaft is mounted in the guide groove. The clutch shaft moves radially under the push of a spring.

[0009] It also includes a coupling groove, which is arranged on the cylindrical surface of the screw;

[0010] It also includes a concave docking groove set on the end face of the driving gear, the docking groove is sleeved on the outside of the retaining frame, the cross-section of the docking groove is a long waist-shaped connecting part and a separating part, and the width of the connecting part is smaller than the width of the separating part.

[0011] Furthermore, the retaining frame is cylindrical and sleeved on the surface of the screw, the guide groove is set through the rear end surface and the cylindrical surface of the retaining frame, and the clutch shaft slides along the radial direction of the guide groove.

[0012] Furthermore: the clutch shaft is cylindrical, and a spring groove is concavely provided on the cylindrical surface of the clutch shaft, and the supporting foot of the spring is clamped in the spring groove.

[0013] Furthermore, the spring cross section is arranged in a "C" shape, and a spring seat is provided in the middle of the spring to protrude outward. Correspondingly, a mounting groove is provided on the retaining frame, and the spring seat is fixed in the mounting groove.

[0014] Furthermore: the coupling groove is a trapezoidal groove that is wide outside and narrow inside.

[0015] Furthermore, two guide grooves and two coupling grooves are provided, which are symmetrically distributed on the retaining frame and the screw respectively.

[0016] Furthermore: the separation portion is arranged at both ends of the coupling portion, the separation portion is an arc groove extending outward, and the coupling portion is platform-shaped.

[0017] Furthermore: the driving gear is a worm wheel, and the driven gear is a worm.

[0018] Furthermore, the screw is rotatably mounted in the accommodating cavity via a first bearing and a second bearing, and the driving gear is located between the first bearing and the second bearing.

[0019] Furthermore, the driving gear is sleeved on the surface of the keyway shaft, the hollow interior of the keyway shaft is sleeved outside the screw, and the coupling groove is arranged on the end face of the keyway shaft.

[0020] The beneficial effects of the utility model are: 1. Simple structure, low production cost and improved market competitiveness.

[0021] 2. This invention utilizes a unique clutch structure design that automatically disengages the clutch when the motor is not in operation, allowing the screw to rotate freely. In this state, the internal gears and motor do not rotate with the screw, meaning the user can manually push the nut to freely move along the screw's axis. This design enables both electric and manual operation, greatly enhancing the device's flexibility. Manual operation remains functional, especially in the event of motor failure, power outages, or when electric operation is inconvenient.

[0022] 3. The clutch structure of the present invention is relatively simple, eliminating the need for complex mechanical components. This not only reduces manufacturing costs but also simplifies subsequent maintenance. Because the clutch automatically disengages, mechanical wear caused by continued gear rotation after the motor stops is reduced, thereby improving the overall reliability of the system.

[0023] 4. The clutch structure of the present invention is automatically in a disengaged state when the motor is not working. Therefore, when the user does not know that the device has an electric opening and closing function and chooses to force it to open manually, the device will not be damaged by being opened violently. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is the general assembly effect diagram of the utility model.

[0025] Figure 2 This is a schematic diagram of the structure behind the hidden cover in the utility model.

[0026] Figure 3 This is a schematic diagram of the structure after the front cover and bottom shell are hidden in the present invention.

[0027] Figure 4 This is an assembly effect diagram of the driving gear and the driven gear in the utility model.

[0028] Figure 5-7 This is an exploded view of the clutch shaft and retainer in the utility model.

[0029] Figure 8 This is a cross-sectional view of the power combination structure in the utility model.

[0030] Figure 9 This is a cross-sectional view of the power separation structure in the present utility model. DETAILED DESCRIPTION

[0031] The present invention will be further described below in conjunction with the accompanying drawings. A power push rod with a clutch function comprises a bottom shell 1 and a cover 2. The bottom shell 1 is provided with a receiving chamber, in which a reduction gear set 4 driven by a motor 3 is installed. A driving gear 5 is mounted on the output shaft of the reduction gear set 4. The driving gear 5 meshes with a driven gear 7 mounted on the cylindrical surface of a screw 6 and drives the latter to rotate.

[0032] The screw 6 is rotatably mounted in the bottom shell 1 and extends out of the bottom shell 1. A retainer 8 is rotatably mounted on the outside of the screw 6. A plurality of guide grooves 81 are radially extended on the retainer 8. A clutch shaft 82 is mounted in the guide groove 81. The clutch shaft 82 moves radially under the push of a spring 83.

[0033] It also includes a coupling groove 61, which is provided on the cylindrical surface of the screw 6;

[0034] It also includes a docking groove 51 provided on the end face of the driving gear 5, the docking groove 51 is sleeved on the outside of the retaining frame 8, the docking groove 51 has a long waist-shaped cross-section with a connecting portion 52 and a separating portion 53, and the width of the connecting portion 52 is smaller than the width of the separating portion 53.

[0035] In one embodiment, the retainer 8 is cylindrical and sleeved on the surface of the screw 6 , the guide groove 81 passes through the rear end surface and the cylindrical surface of the retainer 8 , and the clutch shaft 82 moves along the radial direction of the guide groove 81 .

[0036] In one embodiment, the clutch shaft 82 is cylindrical, and a spring groove 84 is concavely provided on the cylindrical surface of the clutch shaft 82 , and the supporting foot of the spring 83 is clamped in the spring groove 84 .

[0037] In one embodiment, the cross section of the spring 83 is C-shaped, and a spring seat 85 is provided in the middle of the spring 83 to protrude outward. Correspondingly, a mounting groove 86 is provided on the retaining frame 8, and the spring seat 85 is fixed in the mounting groove 86.

[0038] In one embodiment, the coupling groove 61 is a trapezoidal groove that is wide on the outside and narrow on the inside.

[0039] In one embodiment, two guide grooves 81 and two coupling grooves 61 are provided, which are symmetrically distributed on the retaining frame 8 and the screw rod 6 respectively.

[0040] In one embodiment, the separation portion 53 is provided at both ends of the coupling portion 52 . The separation portion 53 is an arc groove extending outward, and the coupling portion 52 is in the shape of a platform.

[0041] In one embodiment, the driving gear 5 is a worm wheel, and the driven gear 7 is a worm.

[0042] In one embodiment, the screw rod 6 is rotatably mounted in the accommodating cavity via a first bearing 62 and a second bearing 63 , and the driving gear 5 is located between the first bearing 62 and the second bearing 63 .

[0043] In one embodiment, the driving gear 5 is sleeved on the surface of the keyway shaft 9 , the keyway shaft 9 is hollow inside and sleeved outside the screw, and the coupling groove 61 is provided on the end surface of the keyway shaft 9 .

[0044] Working principle:

[0045] Electric mode: When motor 3 is started, its rotational power is transmitted through reduction gear set 4, and the output shaft of the reduction gear set ultimately drives driving gear 5. Driving gear 5 meshes with driven gear 7 mounted on the cylindrical surface of screw 6, thereby driving driven gear 7 and the keyway shaft to rotate.

[0046] In the clutch mechanism, retainer 8 controls the movement of clutch shaft 82 via radially extending guide slots 81. Driven by spring 83, clutch shaft 82 consistently maintains a tendency to move outward from the clutch shaft's center. However, when the motor is operating, the rotation of the driving gear causes the docking slot 51 to interact with retainer 8. Specifically, the engaging portion 52 and the separating portion 53 of the docking slot 51 are designed with specific geometric shapes. During rotation driven by the driving gear, the engaging portion pushes the small cylindrical clutch shaft 82 within retainer 8 toward the center of the circle.

[0047] As the driving gear rotates further, the clutch shaft 82 gradually overcomes the return force of the spring 83 and finally snaps into the coupling groove 61 on the screw rod 6, thus achieving dynamic coupling between the screw rod 6 and the driving gear 5. At this time, the power of the motor is smoothly transmitted to the screw rod 6 through the driving gear 5, the driven gear 7 and the clutch device, driving the screw rod to rotate, thereby achieving the telescopic movement of the push rod.

[0048] In manual mode: When the motor stops working, the driving gear 5 stops rotating. At this time, due to the force of the spring 83, the clutch shaft 82 will rebound quickly and disengage from the coupling groove 61 on the screw 6. As the clutch shaft disengages and enters the separation portion, the power connection between the screw 6 and the driving gear 5 is cut off, and the screw 6 enters a free rotation state.

[0049] In this state, the user can manually operate the screw, causing it to rotate freely along its axis and drive the nut along its axial direction. Since the internal gears and motor are no longer involved in power transmission, manual operation is easy and smooth, unhindered by the motor and gear train. This design ensures compatibility between electric and manual operation, making it particularly convenient to switch to manual mode if the motor is damaged or power is lost, or if the user is unaware of the electric opening function and forces manual opening.

[0050] Compared to conventional technologies, the clutch device of this invention automatically switches according to the motor's operating state, making the transition between electric and manual operation much simpler. Users can freely switch between the two modes without additional operation, greatly improving operational convenience and flexibility.

[0051] In addition, the clutch device achieves smooth transmission of motor power through the precise engagement of the clutch shaft 82 with the coupling groove 61. This not only improves the transmission efficiency of the system, but also reduces the wear and tear of the motor and gear train caused by manual operation, extending the service life of the equipment.

[0052] Furthermore, in manual mode, the clutch automatically disengages completely, freeing the screw's rotation from the gear train and motor, allowing for easy manual operation. This feature is extremely practical, ensuring the device remains operational in the event of an emergency manual adjustment or power failure.

[0053] Through the automatic disengagement and engagement of the clutch, the present invention can effectively avoid the ineffective rotation of the motor caused by external force when it is not working, reduce unnecessary mechanical wear, thereby protecting the internal gear set and motor, and ensuring the long-term stable operation of the system.

[0054] In summary, the present invention realizes automatic switching between electric and manual operation and efficient power transmission through the ingenious design of the clutch device, which significantly improves the flexibility and reliability of the electric push rod and can therefore be widely promoted and used.

[0055] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and improvements shall fall within the scope of the present invention as claimed.

Claims

1. An electric linear actuator with a clutch function, characterized in that: It comprises a bottom shell (1) and a cover (2); a receiving cavity is provided in the bottom shell (1); a reduction gear set (4) driven by a motor (3) is installed in the receiving cavity; a driving gear (5) is installed on the output shaft of the reduction gear set (4); the driving gear (5) meshes with a driven gear (7) sleeved on the cylindrical surface of a screw rod (6) and drives the latter to rotate; The screw (6) is rotatably mounted in the bottom shell (1) and extends out of the bottom shell (1). A retainer (8) is rotatably mounted on the outside of the screw (6). A plurality of guide grooves (81) are radially extended on the retainer (8). A clutch shaft (82) is mounted in the guide groove (81). The clutch shaft (82) moves radially under the push of a spring (83). It also includes a coupling groove (61), wherein the coupling groove (61) is provided on the cylindrical surface of the screw rod (6); The invention also includes a docking groove (51) provided on the end surface of the driving gear (5), wherein the docking groove (51) is sleeved on the outside of the retaining frame (8), and the docking groove (51) includes a connecting portion (52) and a separating portion (53) with a long waist-shaped cross section, wherein the width of the connecting portion (52) is smaller than the width of the separating portion (53).

2. The electric linear actuator with clutch function according to claim 1, characterized in that: The retainer (8) is cylindrical and sleeved on the surface of the screw (6). The guide groove (81) passes through the rear end surface of the retainer (8) and the cylindrical surface thereof. The clutch shaft (82) moves along the radial direction of the guide groove (81).

3. The electric linear actuator with clutch function according to claim 1 or 2, characterized in that: The clutch shaft (82) is cylindrical, and a spring groove (84) is concavely provided on the cylindrical surface of the clutch shaft (82), and the supporting foot of the spring (83) is clamped in the spring groove (84).

4. The electric linear actuator with clutch function according to claim 3, characterized in that: The cross section of the spring (83) is arranged in a "C" shape, and a spring seat (85) is provided in the middle of the spring (83) to protrude outward. Correspondingly, a mounting groove (86) is provided on the retaining frame (8), and the spring seat (85) is fixed in the mounting groove (86).

5. The electric linear actuator with clutch function according to claim 1, characterized in that: The coupling groove (61) is a trapezoidal groove that is wide on the outside and narrow on the inside.

6. The electric linear actuator with clutch function according to claim 1, characterized in that: There are two guide grooves (81) and two coupling grooves (61), which are symmetrically distributed on the retaining frame (8) and the screw (6).

7. The electric linear actuator with clutch function according to claim 1, characterized in that: The separation portion (53) is arranged at both ends of the coupling portion (52); the separation portion (53) is an arc groove extending outward, and the coupling portion (52) is platform-shaped.

8. The electric linear actuator with clutch function according to claim 1, characterized in that: The driving gear (5) is a worm wheel, and the driven gear (7) is a worm.

9. The electric linear actuator with clutch function according to claim 1, characterized in that: The screw (6) is rotatably mounted in the accommodating cavity via a first bearing (62) and a second bearing (63), and the driving gear (5) is located between the first bearing (62) and the second bearing (63).

10. The electric linear actuator with clutch function according to claim 1, characterized in that: The driving gear (5) is sleeved on the surface of the keyway shaft (9), the keyway shaft (9) is hollow inside and sleeved outside the screw, and the coupling groove (61) is provided on the end face of the keyway shaft (9).

Images