Electric push rod

Abstract

The utility model discloses an electric push rod, comprising a screw rod telescoping device which comprises a square tube, and a screw rod and a nut arranged in the inner cavity of the square tube; a first bevel gear connected with one end of the lead screw is arranged in the gearbox; the driving motor is arranged on one side of the gearbox; the transmission device is arranged in the containing cavity in the gearbox and used for being in transmission connection with the first bevel gear and the driving motor; a driving motor is arranged in the square tube, a screw rod is arranged in the square tube, a stroke strip is arranged in the square tube, limiting devices are fixedly arranged at the two ends of the stroke strip, switches used for controlling the driving motor to be turned off are arranged on the limiting devices in a protruding mode, and a protruding block used in cooperation with the switches is arranged on one side of the nut. A bump arranged on the nut moves upwards along with the nut so as to touch a switch on the limiting device, so that the effect of closing the driving motor is achieved, and the situation that the nut is separated from the lead screw due to excessive movement is prevented.

Description

Technical Field

[0001] This utility model relates to the field of electric linear actuator technology, and in particular to an electric linear actuator. Background Technology

[0002] An electric linear actuator is an electrically driven device that converts the rotary motion of an electric motor into the linear reciprocating motion of a linear actuator. It can be used as an actuator in various simple or complex processes to achieve remote control, centralized control, or automatic control.

[0003] Most existing electric linear actuators use a lead screw with a gear, which transmits the rotational power of the drive motor to rotate the gear on the lead screw, thus achieving the effect of rotating the lead screw. The linear reciprocating motion of the actuator is controlled by a nut fitted on the lead screw. However, in long-term use, it has been found that excessive up-and-down movement of the nut on the lead screw can cause the nut to rotate away from the lead screw, resulting in the actuator failing to operate.

[0004] For the reasons mentioned above, it is necessary to improve the existing technology. Utility Model Content

[0005] I. Technical problems to be solved

[0006] This utility model addresses the aforementioned deficiencies in the existing technology by proposing an electric actuator to solve the problems mentioned in the background art.

[0007] II. Technical Solution

[0008] To solve the above-mentioned technical problems, this utility model provides an electric linear actuator, including a lead screw telescopic device, wherein the lead screw telescopic device includes a square tube, a lead screw disposed in the inner cavity of the square tube, and a nut movably disposed on the lead screw;

[0009] A gearbox, wherein a first helical gear is provided inside the gearbox and connected to one end of a lead screw;

[0010] A drive motor is disposed on one side of the gearbox;

[0011] A transmission device is disposed in the internal cavity of the gearbox and is used to drive the first helical gear and the drive motor.

[0012] The square tube is provided with a travel bar, and limit devices are fixedly provided at both ends of the travel bar. A switch for controlling the drive motor to turn off is protruding on the limit device, and a protrusion for cooperating with the switch is provided on one side of the nut.

[0013] In the above technical solution, the transmission device includes a worm sleeve disposed at one end of the drive motor and a second helical gear disposed in the gearbox via a shaft pin. A worm wheel is sleeved and fixed on the shaft pin, the worm wheel meshes with the worm sleeve, and the second helical gear meshes with the first helical gear.

[0014] In the above technical solution, two bearings are sleeved on the lead screw, and the bearings are respectively set at both ends of the first helical gear. The gearbox is provided with bearing grooves for accommodating the bearings.

[0015] In the above technical solution, the first helical gear and the second helical gear are made of plastic.

[0016] In the above technical solution, the nut is provided with a slider, and the square tube is provided with a groove that cooperates with the slider.

[0017] In the above technical solution, the square tube is provided with a limiting groove, and the two ends of the stroke bar are provided with protrusions that cooperate with the limiting groove.

[0018] III. Beneficial Effects

[0019] Compared with the prior art, the present invention has the following advantages: The present invention sets a travel bar on the square tube, and sets a limiting device at both ends of the travel bar with the same length as the lead screw. The protrusion on the nut moves upward with the nut and touches the switch on the limiting device to shut off the drive motor, thereby preventing the nut from moving too far and causing it to disengage from the lead screw. Attached Figure Description

[0020] Figure 1 It is a schematic diagram of the three-dimensional structure of the utility model.

[0021] Figure 2 This is a cross-sectional structural diagram of the present invention.

[0022] Figure 3 This is a schematic diagram of the exploded structure of this utility model.

[0023] Figure 4 This is a partial structural schematic diagram of the present invention.

[0024] In the diagram: 1 is the lead screw telescopic device, 10 is the square tube, 11 is the lead screw, 12 is the nut, 13 is the bearing, 100 is the slide groove, 101 is the travel bar, 102 is the limiting device, 103 is the switch, 104 is the limiting groove, 120 is the slider, 121 is the protrusion, 1000 is the shaft pin, 1010 is the protrusion, 2 is the gearbox, 20 is the first helical gear, 21 is the bearing groove, 3 is the drive motor, 4 is the transmission device, 40 is the worm sleeve, 41 is the second helical gear, and 42 is the worm. Detailed Implementation

[0025] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but should not be used to limit the scope of this utility model.

[0026] Please see Figure 1-4 The present invention provides an electric push rod, including a lead screw telescopic device 1, wherein the lead screw telescopic device 1 includes a square tube 10, a lead screw 11 disposed in the inner cavity of the square tube 10, and a nut 12 movably disposed on the lead screw 11;

[0027] Gearbox 2, wherein a first helical gear 20 is provided inside the gearbox 2 and is connected to one end of the lead screw 11;

[0028] A drive motor 3 is disposed on one side of the gearbox 2;

[0029] The transmission device 4 is disposed in the internal cavity of the gearbox 2 and is used to drive the first helical gear 20 and the drive motor 3.

[0030] The square tube 10 is provided with a travel bar 101. Limiting devices 102 are fixedly provided at both ends of the travel bar 101. A switch 103 for controlling the drive motor 3 to turn off is provided on the limiting device 102. A protrusion 121 for cooperating with the switch 103 is provided on one side of the nut 12.

[0031] In the above scheme, when the electric push rod is working, the force of the drive motor is transmitted to the first helical gear through the transmission device, causing the first helical gear located at one end of the lead screw to rotate, thereby driving the lead screw to rotate. The rotation of the lead screw drives the nut mounted on it to perform a linear reciprocating motion of up and down. A travel bar of the same length as the lead screw is provided on one side of the lead screw, and limit devices are provided at both ends of the travel bar. The limit devices are equipped with switches for controlling the drive motor to turn off. When the nut rotates to the position of the limit device, the protrusion on the nut presses against the switch, causing the drive motor to turn off. The drive motor turning off causes the lead screw to stop rotating, thereby stopping the nut from moving up and down, effectively preventing the nut from moving excessively and detaching from the lead screw.

[0032] Specifically, the transmission device 4 includes a worm sleeve 40 disposed at one end of the drive motor 3 and a second helical gear 41 disposed in the gearbox 2 via a shaft pin 1000. A worm wheel 42 is sleeved and fixed on the shaft pin 1000. The worm wheel 42 meshes with the worm sleeve 40, and the second helical gear 41 meshes with the first helical gear 20. Using gears as the transmission device has a better transmission effect.

[0033] Specifically, two bearings 13 are sleeved on the lead screw 11. The bearings 13 are respectively set at both ends of the first helical gear 20. The gearbox 2 is provided with bearing grooves 21 for accommodating the bearings 13. The bearings set in the bearing grooves are used to hold the position of the first helical gear, which plays a limiting role. At the same time, the bearings can support the first helical gear and reduce the friction during the rotation of the first helical gear.

[0034] Specifically, the first helical gear 20 and the second helical gear 41 are made of plastic. Using plastic can reduce the noise generated by gear meshing and rotation, and also reduce costs.

[0035] Specifically, the nut 12 has a protruding slider 120, and the square tube 10 has a groove 100 inside that works with the slider 120. The groove and the slider work together to guide the movement of the nut.

[0036] Specifically, the square tube 10 is provided with a limiting groove 104, and the two ends of the travel bar 101 are provided with protrusions 1010 that cooperate with the limiting groove 104. The limiting groove and the protrusions are used to limit the position of the travel bar on the square tube and prevent the travel bar from shifting.

[0037] The above are merely preferred embodiments of this utility model. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model.

Claims

1. An electric linear actuator, comprising: A lead screw telescopic device (1) includes a square tube (10), a lead screw (11) disposed in the inner cavity of the square tube (10), and a nut (12) movably disposed on the lead screw (11); Gearbox (2), wherein a first helical gear (20) connected to one end of lead screw (11) is provided inside the gearbox (2); A drive motor (3) is disposed on one side of the gearbox (2); a transmission device (4) is disposed in the internal cavity of the gearbox (2) and is used to drive the first helical gear (20) and the drive motor (3); characterized in that: The square tube (10) is provided with a travel bar (101), and the two ends of the travel bar (101) are fixedly provided with limit devices (102). The limit device (102) is provided with a switch (103) for controlling the drive motor (3) to close. The nut (12) is provided with a protrusion (121) on one side that cooperates with the switch (103).

2. The electric linear actuator as described in claim 1, characterized in that: The transmission device (4) includes a worm sleeve (40) disposed at one end of the drive motor (3) and a second helical gear (41) disposed in the gearbox (2) via a shaft pin (1000). A worm wheel (42) is sleeved and fixed on the shaft pin (1000). The worm wheel (42) meshes with the worm sleeve (40), and the second helical gear (41) meshes with the first helical gear (20).

3. An electric linear actuator as described in claim 1, characterized in that: Two bearings (13) are fitted on the lead screw (11), and the bearings (13) are respectively located at both ends of the first helical gear (20). The gearbox (2) is provided with bearing grooves (21) for accommodating the bearings (13).

4. An electric linear actuator as described in claim 2, characterized in that: The first helical gear (20) and the second helical gear (41) are made of plastic.

5. An electric linear actuator as described in claim 1, characterized in that: The nut (12) has a protruding slider (120), and the square tube (10) has a groove (100) inside that works in conjunction with the slider (120).

6. An electric linear actuator as described in claim 1, characterized in that: The square tube (10) is provided with a limiting groove (104), and the two ends of the travel bar (101) are provided with protrusions (1010) that cooperate with the limiting groove (104).

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