Electric push rod with adjustable stroke

Abstract

An electric push rod with an adjustable stroke comprises a screw rod, a nut, a driving device, a transmission gear assembly, a stroke adjusting assembly, a stroke control assembly, a transmission protection shell and a base box body, the stroke adjusting assembly is arranged in the base box body, and the stroke adjusting assembly is connected with the transmission gear assembly. The transmission gear assembly is arranged in the transmission protection shell and meshed with an output shaft of the driving device, the transmission gear assembly is connected with a screw rod, and the screw rod is connected with a nut; the stroke adjusting assembly comprises an upper cam, a lower cam, an upper microswitch, a lower microswitch, a spring and a spring shell, the upper microswitch is movably connected with a protruding part of the upper cam, the lower microswitch is movably connected with a protruding part of the lower cam, the upper cam is movably connected with the lower cam, a movable cavity is formed in the upper cam, and the spring shell is arranged in the movable cavity. The spring shell is inserted into the movable cavity, the upper end of the spring is inserted into the spring shell, a rotating shaft is movably arranged in the lower cam, the upper end of the rotating shaft is inserted into the spring, and the lower end of the rotating shaft penetrates through the base box to be connected with the transmission gear assembly. According to the utility model, the stroke adjusting function is realized under the mutual cooperation of the upper microswitch and the upper cam, the lower microswitch and the lower cam as well as the spring, and the operation is convenient; by arranging the stroke adjusting assembly in the base box body, the device has the advantages of being simple in structure, convenient to install, beneficial to maintenance, high in practicability and the like.

Description

Technical Field

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

[0002] An electric push rod, also known as a push rod motor, an electric cylinder and a linear actuator, is a power-driven device that converts the rotational motion of a motor into the linear reciprocating motion of a push rod. The telescopic motion of the push rod is realized by the forward and reverse rotation of the motor. It can be used as an execution machine in various simple or complex technological processes to achieve remote control, centralized control or automatic control. Due to its simple structure and other advantages, it is widely used in daily products, such as electric sofas, lift beds and other electric lifting mechanisms. The maximum stroke of the electric push rod is set at the factory, but it needs to be adjusted according to requirements during actual use. In the prior art, the stroke control structure of the electric push rod is usually arranged on the inner wall of the outer tube of the push rod. However, the wiring of this kind of stroke control switch is numerous and long, relatively complex, and it is not easy to fix and adjust the stroke of the push rod, and it is not easy to troubleshoot when a failure occurs. Therefore, an electric push rod with adjustable stroke is needed to improve the above problems. Content of the Utility Model

[0003] The purpose of the utility model is to provide an electric push rod with adjustable stroke, aiming to solve the above technical problems. The utility model realizes the stroke adjustment function through the mutual cooperation of an upper micro switch and an upper cam, a lower micro switch and a lower cam, and a spring; by arranging the stroke adjustment component in the base box body, the problem of complex wiring of the traditional stroke adjustment structure is avoided, and the installation is convenient, which is beneficial to maintenance. At the same time, the method of adjusting the stroke of the push rod is simple and has strong practicability.

[0004] In order to achieve the above purpose, the utility model is realized through the following technical solutions:

[0005] An electric push rod with adjustable stroke includes a screw rod, a nut, a driving device, a transmission gear assembly, a stroke adjustment component, a stroke control component, a transmission protective shell and a base box body. The stroke adjustment component is arranged in the base box body. The stroke adjustment component is connected with the transmission gear assembly. The transmission gear assembly is arranged in the transmission protective shell and meshes with the output shaft of the driving device. The transmission gear assembly is connected with the screw rod, and the screw rod is connected with the nut;

[0006] The stroke adjustment assembly includes an upper cam, a lower cam, an upper microswitch, a lower microswitch, a spring and a spring housing. The upper microswitch is movably connected to the convex part of the upper cam, the lower microswitch is movably connected to the convex part of the lower cam, the upper cam is movably connected to the lower cam. An activity cavity is provided in the upper cam, the spring housing is inserted into the activity cavity, the upper end of the spring is inserted into the spring housing, a rotating shaft is movably arranged in the lower cam, the upper end of the rotating shaft is inserted into the spring, and the lower end of the rotating shaft passes through the base box body and is connected to the transmission gear assembly.

[0007] Further, the transmission gear assembly includes a rotating gear set, a helical gear set and a main gear structure. The helical gear set is located between the rotating gear set and the main gear structure. The lower end of the rotating shaft passes through the base box body and is connected to the rotating gear set. Both the helical gear set and the rotating gear set are meshed with the output shaft of the driving device. The main gear structure is connected to the screw rod. The main gear structure includes a main gear, and the main gear is meshed with the helical gear set.

[0008] Further, the rotating gear set includes a first rotating gear, a second rotating gear, a third rotating gear, a fourth rotating gear, a first transmission shaft and a second transmission shaft. The first rotating gear is located above the second rotating gear, the third rotating gear is located above the fourth rotating gear. The first transmission shaft passes through the middle positions of the first rotating gear and the second rotating gear, and the second transmission shaft passes through the middle positions of the third rotating gear and the fourth rotating gear. The first rotating gear is meshed with the third rotating gear, the third rotating gear is meshed with the second rotating gear, the second rotating gear is meshed with the fourth rotating gear, and the fourth rotating gear is meshed with the helical gear set.

[0009] Further, the rotating gear set further includes a cam connecting gear. The cam connecting gear is meshed with the first rotating gear. The lower end of the rotating shaft is connected to the cam connecting gear. A cam connecting hole is provided in the middle position of the cam connecting gear, and the lower end of the rotating shaft is movably connected to the cam connecting hole.

[0010] Further, the helical gear set includes a small helical gear, a large helical gear, a third transmission shaft and a fourth transmission shaft. The third transmission shaft passes through the middle position of the small helical gear, and the fourth transmission shaft passes through the middle position of the large helical gear. The upper end of the small helical gear is meshed with the fourth rotating gear, the lower end of the small helical gear is meshed with the output shaft of the driving device, the upper end of the large helical gear is meshed with the output shaft of the driving device, and the lower end of the large helical gear is meshed with the main gear.

[0011] Further, the main gear structure further includes two ball bearings. The two ball bearings are respectively sleeved outside the screw rod and are respectively located on both sides of the main gear.

[0012] Furthermore, the stroke control assembly includes a potentiometer, a potentiometer gear, a fifth rotating gear, and a sixth rotating gear. The potentiometer is installed inside the base box. The lower end of the potentiometer is connected to the potentiometer gear. The potentiometer gear meshes with the fifth rotating gear. The lower end of the fifth rotating gear is connected to the sixth rotating gear. The sixth rotating gear meshes with the third rotating gear.

[0013] Furthermore, a relay and a PCB board are also installed inside the base box. A wire connector is installed on the outer side of the base box. The wire connector is electrically connected to the relay. The relay is electrically connected to the PCB board. The PCB board is electrically connected to the drive device, the potentiometer, and the microswitch.

[0014] Furthermore, an inner tube and an outer tube are also included. The inner tube is connected to the nut and sleeved outside the screw rod. The outer tube is sleeved outside the inner tube and connected to the transmission protective shell.

[0015] Furthermore, a skeleton oil seal and a screw rod protective sleeve are also included. The skeleton oil seal is arranged between the transmission protective shell and the outer tube. The screw rod protective sleeve is fixed on the base box. The upper end of the screw rod is located inside the screw rod protective sleeve.

[0016] The electric push rod with adjustable stroke of the present utility model has the following beneficial effects:

[0017] 1. For the electric push rod with adjustable stroke of the present utility model, by setting two microswitches, the upper microswitch, the upper cam, the lower microswitch, the lower cam, and the spring cooperate with each other to realize the stroke adjustment function: when the lower cam cuts off the connection with the lower microswitch, the push rod is in the retracted state; when the upper cam cuts off the connection with the upper microswitch, the push rod is in the extended state. When the stroke needs to be adjusted, the upper cam is lifted upward by the telescopic spring and then rotated to obtain the desired stroke. After completion, the upper cam is moved downward, and at this time, the spring automatically extends and resets to fix the upper cam. The operation is convenient, and it can also prevent damage to the gears, with strong practicability.

[0018] 2. For the electric push rod with adjustable stroke of the present utility model, by arranging the stroke adjustment assembly inside the base box, the problem of complex wiring of the traditional stroke adjustment structure is avoided. Moreover, the installation is convenient, which is conducive to maintenance. At the same time, the method of adjusting the stroke of the push rod is simple, with strong practicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the present utility model;

[0020] Figure 2 It is a schematic diagram of the disassembled structure of the present utility model;

[0021] Figure 3Structural schematic diagrams of the driving device, transmission gear assembly, stroke adjustment assembly, and stroke control assembly of the present utility model;

[0022] Figure 4 For Figure 3 Structural schematic diagrams of the driving device, transmission gear assembly, and stroke adjustment assembly shown;

[0023] Figure 5 For Figure 4 Partial structural exploded view of the stroke adjustment assembly and the rotating gear set shown;

[0024] Figure 6 For Figure 4 Structural exploded view of the upper cam, lower cam, spring, and spring housing shown; Figure 1 ;

[0025] Figure 7 For Figure 4 Structural exploded view of the upper cam, lower cam, spring, and spring housing shown; Figure 2 . Specific embodiments

[0026] In order to enable those skilled in the art of the present technology to better understand the technical solutions of the present utility model, the products of the present utility model will be further described in detail below in conjunction with embodiments and the accompanying drawings.

[0027] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may also be an intermediate element; when an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation manner.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present utility model belongs. The terms used in the description of the present utility model herein are only for the purpose of describing specific embodiments and are not intended to limit the present utility model. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0029] Such as Figure 1 、 Figure 2 And Figure 5As shown in the figure, an electric push rod with adjustable stroke includes a screw rod 1, a nut 2, a driving device 3, a transmission gear assembly 4, a stroke adjustment assembly 5, a stroke control assembly 6, a transmission protective shell 7 and a base box body 8. The stroke adjustment assembly 5 is arranged in the base box body 8. The stroke adjustment assembly 5 is connected to the transmission gear assembly 4. The transmission gear assembly 4 is arranged in the transmission protective shell 7 and meshes with the output shaft of the driving device 3. The transmission gear assembly 4 is connected to the screw rod 1, and the screw rod 1 is connected to the nut 2;

[0030] The stroke adjustment assembly 5 includes an upper cam 50, a lower cam 51, an upper microswitch 52, a lower microswitch 53, a spring 54 and a spring housing 55. The upper microswitch 52 is movably connected to the protrusion of the upper cam 50. The lower microswitch 53 is movably connected to the protrusion of the lower cam 51. The upper cam 50 and the lower cam 51 are movably clamped and connected. An activity cavity 56 is arranged in the upper cam 50. The spring housing 55 is inserted into the activity cavity 56. The upper end of the spring 54 is inserted into the spring housing 55. A rotating shaft 57 is movably arranged in the lower cam 51. The upper end of the rotating shaft 57 is inserted into the spring 54. The lower end of the rotating shaft 57 passes through the base box body 8 and is connected to the transmission gear assembly 4.

[0031] It should be noted that a screw is installed on the spring housing 55. The spring 54 and the spring housing 55 are positioned and fixed by the screw. The lower end of the screw is inserted into the interior of the rotating shaft 57. The position of the spring housing 55 is fixed. When the upper cam 50 is lifted upward, the upper cam 50 moves upward to push the spring 54 into the spring housing 55. When the upper cam 50 moves downward, the spring 54 is reset, so that the upper cam 50 is clamped on the lower cam 51 for fixation.

[0032] As Figure 5 shown, the outer side of the upper cam 50 is symmetrically provided with protruding grasping parts 58, which have the effects of anti-slip and convenient operation.

[0033] It should be noted that in this utility model, by setting two microswitches, the upper microswitch 52, the upper cam 50, the lower microswitch 53, the lower cam 51 and the spring 54 cooperate with each other to realize the stroke adjustment function;

[0034] Stroke adjustment method: When the lower cam 51 cuts off the connection with the lower microswitch 53, the push rod is in the retracted and stationary state. At this time, the upper cam 50 is connected to the upper microswitch 52; when the upper cam 50 cuts off the connection with the upper microswitch 52, the push rod is in the extended state. At this time, the lower cam 51 is connected to the lower microswitch 53; when adjusting the stroke, use the expansion and contraction of the spring 54 to lift the upper cam 50 upward and then rotate it to obtain the desired stroke. At this time, when the upper cam 50 cuts off the connection with the upper microswitch 52, after completion, move the upper cam 50 downward. At this time, the spring 54 automatically extends and resets to fix the upper cam 50;

[0035] It should be further noted that place the index finger and thumb on the grasping part 58 of the upper cam 50 respectively, then lift the upper cam 50 upward with force, and then rotate the upper cam 50 counterclockwise. At this time, the corresponding push rod stroke is shortened. On the contrary, when rotating clockwise, the push rod stroke is increased.

[0036] As Figure 3 and Figure 4 As shown in the figure, the transmission gear assembly 4 includes a rotating gear set, a helical gear set and a main gear structure. The helical gear set is located between the rotating gear set and the main gear structure. The lower end of the rotating shaft 57 passes through the base box 8 and is connected to the rotating gear set. Both the helical gear set and the rotating gear set are meshed with the output shaft of the driving device 3. The main gear structure is connected to the screw 1. The main gear structure includes a main gear 40, and the main gear 40 is meshed with the helical gear set.

[0037] As Figures 3 to 5 As shown in the figure, the rotating gear set includes a first rotating gear 410, a second rotating gear 411, a third rotating gear 412, a fourth rotating gear 413, a first transmission shaft 414 and a second transmission shaft 415. The first rotating gear 410 is located above the second rotating gear 411. The third rotating gear 412 is located above the fourth rotating gear 413. The first transmission shaft 414 passes through the middle positions of the first rotating gear 410 and the second rotating gear 411. The second transmission shaft 415 passes through the middle positions of the third rotating gear 412 and the fourth rotating gear 413. The lower end of the first rotating gear 410 is meshed with the upper end of the third rotating gear 412. The lower end of the third rotating gear 412 is meshed with the upper end of the second rotating gear 411. The lower end of the second rotating gear 411 is meshed with the upper end of the fourth rotating gear 413. The lower end of the fourth rotating gear 413 is meshed with the helical gear set.

[0038] It should be noted that an angle is formed between the convex part of the upper cam 50 and the convex part of the lower cam 51. When the lower cam 51 cuts off the connection with the lower microswitch 53, the push rod is in a retracted and stationary state. At this time, the upper cam 50 is connected to the upper microswitch 52. When the stroke needs to be adjusted, the upper cam 50 is lifted upward by the expansion and contraction of the spring 54 and then rotated to obtain the desired stroke. At this time, rotating the upper cam 50 drives the rotating shaft 57 to rotate, thereby driving the cam connection gear 416, the rotating gear set, the bevel gear set, and the main gear structure to rotate, realizing the function of stroke adjustment.

[0039] As Figures 3 to 5 shown, the rotating gear set further includes a cam connection gear 416. The cam connection gear 416 meshes with the upper end of the first rotating gear 410. The lower end of the rotating shaft 57 is connected to the cam connection gear 416. A cam connection hole is provided at the middle position of the cam connection gear 416, and the lower end of the rotating shaft 57 is adapted to the cam connection hole.

[0040] It should be noted that when the upper cam 50 rotates, it drives the cam connection gear 416 to rotate through the rotating shaft 57. When the lower cam 51 rotates, it drives the cam connection gear 416 to rotate through the rotating shaft 57.

[0041] As Figures 3 to 5 shown, the bevel gear set includes a small bevel gear 417, a large bevel gear 418, a third transmission shaft, and a fourth transmission shaft. The third transmission shaft passes through the middle position of the small bevel gear 417, and the fourth transmission shaft passes through the middle position of the large bevel gear 418. The upper end of the small bevel gear 417 meshes with the fourth rotating gear 413, the lower end of the small bevel gear 417 meshes with the output shaft of the driving device 3, the upper end of the large bevel gear 418 meshes with the output shaft of the driving device 3, and the lower end of the large bevel gear 418 meshes with the main gear 40. The driving device 3 in this embodiment is a driving motor.

[0042] It should be noted that when the rotating gear set rotates, it drives the bevel gear set to rotate, and further drives the main gear 40 to rotate.

[0043] As Figures 3 to 5 shown, the main gear structure further includes two ball bearings 419. The two ball bearings 419 are respectively sleeved outside the screw rod 1 and are respectively located on both sides of the main gear 40.

[0044] As Figure 1 and Figure 2As shown, the stroke control assembly 6 includes a potentiometer 60, a potentiometer gear 61, a fifth rotating gear 62, and a sixth rotating gear 63. The potentiometer 60 is installed in the base box 8. The lower end of the potentiometer 60 is connected to the potentiometer gear 61. The potentiometer gear 61 meshes with the fifth rotating gear 62. The lower end of the fifth rotating gear 62 is connected to the sixth rotating gear 63. The sixth rotating gear 63 meshes with the third rotating gear 412.

[0045] It should be noted that the stroke control function of the stroke control assembly 6 is achieved through the cooperation of the potentiometer gear 61, the fifth rotating gear 62, the sixth rotating gear 63, the large bevel gear 418, and the main gear 40.

[0046] As Figure 1 and Figure 2 shown, a relay 80 and a PCB board 81 are also installed in the base box 8. A wire connector 82 is installed on the outside of the base box 8. The wire connector 82 is electrically connected to the relay 80. The relay 80 is electrically connected to the PCB board 81. The PCB board 81 is electrically connected to the drive device 3, the potentiometer 60, the upper microswitch 52, and the lower microswitch 53.

[0047] As Figure 1 and Figure 2 shown, an inner tube 9 and an outer tube 10 are further included. The inner tube 9 is connected to the nut 2 and sleeved on the screw 1. The outer tube 10 is sleeved outside the inner tube 9 and connected to the transmission protective shell 7. The inner tube 9 functions to expand and contract.

[0048] As Figure 2 and Figure 3 shown, a skeleton oil seal 11 and a screw protective sleeve 12 are further included. The skeleton oil seal 11 is arranged between the transmission protective shell 7 and the outer tube. The screw protective sleeve 12 is fixed on the base box 8. The upper end of the screw 1 is located inside the screw protective sleeve 12.

[0049] The above is only the preferred embodiment of the present invention, and it is not intended to limit the present invention in any form. Any person skilled in the art can smoothly implement the present invention according to the illustrations in the specification and the above description. However, any equivalent changes, such as slight modifications, decorations, and evolutions made by those skilled in the art without departing from the technical solution of the present invention, are equivalent embodiments of the present invention. At the same time, any equivalent changes, such as modifications and evolutions made to the above embodiments based on the essential technology of the present invention, still fall within the protection scope of the technical solution of the present invention.

Claims

1. An electric push rod with adjustable stroke, characterized in that: It includes a screw, a nut, a driving device, a transmission gear assembly, a stroke adjustment assembly, a stroke control assembly, a transmission protective shell and a base box. The stroke adjustment assembly is arranged in the base box, the stroke adjustment assembly is connected to the transmission gear assembly, the transmission gear assembly is arranged in the transmission protective shell and meshes with the output shaft of the driving device, the transmission gear assembly is connected to the screw, and the screw is connected to the nut; The stroke adjustment assembly includes an upper cam, a lower cam, an upper microswitch, a lower microswitch, a spring and a spring housing. The upper microswitch is movably connected to the raised portion of the upper cam, the lower microswitch is movably connected to the raised portion of the lower cam, the upper cam and the lower cam are movably connected, a movable cavity is provided in the upper cam, the spring housing is inserted in the movable cavity, the upper end of the spring is inserted in the spring housing, a rotating shaft is movably provided in the lower cam, the upper end of the rotating shaft is inserted in the spring, and the lower end of the rotating shaft passes through the base box and is connected to the transmission gear assembly.

2. The stroke-adjustable electric push rod according to claim 1, characterized in that: The transmission gear assembly includes a rotating gear group, a helical gear group and a main gear structure. The helical gear group is located between the rotating gear group and the main gear structure. The lower end of the rotating shaft passes through the base box and is connected to the rotating gear group. The helical gear group and the rotating gear group are both engaged with the output shaft of the driving device. The main gear structure is connected to the screw. The main gear structure includes a main gear, and the main gear is engaged with the helical gear group.

3. The electric push rod with adjustable stroke according to claim 2, wherein: The rotating gear group includes a first rotating gear, a second rotating gear, a third rotating gear, a fourth rotating gear, a first transmission shaft and a second transmission shaft. The first rotating gear is located above the second rotating gear, and the third rotating gear is located above the fourth rotating gear. The first transmission shaft passes through the middle position of the first rotating gear and the second rotating gear, and the second transmission shaft passes through the middle position of the third rotating gear and the fourth rotating gear. The first rotating gear is meshed with the third rotating gear, the third rotating gear is meshed with the second rotating gear, the second rotating gear is meshed with the fourth rotating gear, and the fourth rotating gear is meshed with the helical gear group.

4. The electric push rod with adjustable stroke according to claim 3, characterized in that: The rotating gear set also includes a cam connecting gear, which is engaged with the first rotating gear. The lower end of the rotating shaft is connected to the cam connecting gear. A cam connecting hole is provided in the middle of the cam connecting gear. The lower end of the rotating shaft is movably connected to the cam connecting hole.

5. The stroke-adjustable electric push rod according to claim 4, characterized in that: The helical gear set includes a small helical gear, a large helical gear, a third transmission shaft and a fourth transmission shaft. The third transmission shaft passes through the middle of the small helical gear, and the fourth transmission shaft passes through the middle of the large helical gear. The upper end of the small helical gear is engaged with the fourth rotating gear, and the lower end of the small helical gear is engaged with the output shaft of the driving device. The upper end of the large helical gear is engaged with the output shaft of the driving device, and the lower end of the large helical gear is engaged with the main gear.

6. The electric linear actuator with adjustable stroke according to claim 5, characterized in that: The main gear structure further includes two ball bearings, which are respectively sleeved outside the screw and located on both sides of the main gear.

7. The stroke-adjustable electric push rod according to claim 5, characterized in that: The stroke control assembly includes a potentiometer, a potentiometer gear, a fifth rotating gear and a sixth rotating gear. The potentiometer is installed in the base box. The lower end of the potentiometer is connected to the potentiometer gear, and the potentiometer gear is engaged with the fifth rotating gear. The lower end of the fifth rotating gear is connected to the sixth rotating gear, and the sixth rotating gear is engaged with the third rotating gear.

8. The stroke-adjustable electric push rod according to claim 7, wherein: A relay and a PCB board are also installed in the base box, and a wire connector is installed on the outside of the base box. The wire connector is electrically connected to the relay, the relay is electrically connected to the PCB board, and the PCB board is electrically connected to the drive device, potentiometer and micro switch.

9. The electric push rod with adjustable stroke according to claim 1, wherein: It also includes an inner tube and an outer tube, wherein the inner tube is connected to the nut and sleeved on the outside of the screw, and the outer tube is sleeved on the outside of the inner tube and connected to the transmission protective shell.

10. The electric push rod with adjustable stroke according to claim 9, characterized in that: It also includes a skeleton oil seal and a screw protection sleeve, and the skeleton oil seal is arranged between the transmission protection shell and the outer tube, the screw protection sleeve is fixed on the base box, and the upper end of the screw is located in the screw protection sleeve.

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