Limiting module for venetian blind

Abstract

The limiting module comprises a shell assembly, a main shaft, a first screw rod, a second screw rod and a switch assembly, the main shaft is rotationally installed in the shell assembly, and the first screw rod and the second screw rod are arranged on the two sides of the main shaft respectively; an outer tooth part is arranged on the peripheral surface of the main shaft, a first gear meshed with the outer tooth part is arranged on the peripheral side of the first screw rod in a threaded sleeving mode, and a second gear meshed with the outer tooth part is arranged on the peripheral side of the second screw rod in a threaded sleeving mode. The switch assembly comprises a control circuit board, an elastic reed, a first trigger and a second trigger, the first trigger sleeves the first screw in a sliding manner, and the elastic reed is fixed between the first trigger and the control circuit board; the elastic reed is locally provided with a first contact, the control circuit board is locally provided with a second contact, and the first contact is in contact with the second contact to control the transmission rod to stop rotating. On the basis, the abrasion condition between the two contacts can be reduced in the using process, so that the limiting module can keep a good service life.

Description

Technical Field

[0001] The present application relates to the field of door and window design, and in particular to a position limiting module for a venetian blind. Background Art

[0002] Built-in blinds insulating glass, also known as blinds, is a new energy-saving product that combines glass windows and blinds into one, which saves usage space and inconvenience, and achieves the comprehensive performance of insulating glass insulation and blinds sunshade.

[0003] The control methods of Venetian blinds mainly include manual control and electric control. Among them, the control module of electric Venetian blinds includes a Venetian blind motor, a transmission rod, a rope winder and a limiter. The transmission rod is passed through the rope winder and the limiter. The Venetian blind motor is fixedly connected to one end of the transmission rod to drive the transmission rod to rotate. The rope winder is used to reel in the pull cord of the Venetian blind to complete the lifting and flipping of the Venetian blind, and the limiter is used to limit the lifting and flipping of the Venetian blind, that is, the Venetian blind can stop moving after it is fully unfolded or fully folded.

[0004] The limiter is installed inside the window frame of the blinds, and includes an outer shell, a circuit board, two threaded rods, moving gears threadedly connected to the two threaded rods, and moving triggers slidably mounted on the two threaded rods. A positioning trigger is fixed inside the outer shell. When the blinds motor drives the main shaft to rotate, the moving gear moves along the axial direction of the threaded rod and in a direction close to the moving trigger, forcing the moving trigger to contact the positioning trigger, and then sending a signal to the circuit board so that the circuit board sends a control signal to control the blinds motor to stop moving.

[0005] The existing mobile trigger and positioning trigger have two contacts abutting against each other to achieve signal conduction and state change. However, after long-term use, the squeezing and scraping between the two contacts can easily cause damage to the contact position, thereby affecting the accuracy and sensitivity of the contact when the two contacts are in contact, which needs to be improved. Utility Model Content

[0006] Based on this, the present application provides a limit module for a venetian blind, which can reduce the wear between two contacts during use, so as to help the limit module maintain a good service life.

[0007] The present application provides a limit module for a venetian blind using the following technical solution:

[0008] A limit module for a venetian blind comprises a housing assembly, a main shaft, a first screw, a second screw and a switch assembly, wherein the main shaft is rotatably mounted inside the housing assembly, and the first screw and the second screw are both fixedly mounted inside the housing assembly and are arranged on both sides of the main shaft;

[0009] The main shaft is provided with a plug-in groove for the transmission rod to be inserted, the main shaft and the transmission rod are arranged in a circumferential linkage, and the outer peripheral surface of the main shaft is provided with an external tooth portion; the first screw is provided with a first gear on the outer peripheral side of the threaded sleeve, and the second screw is provided with a second gear on the outer peripheral side of the threaded sleeve, the first gear and the second gear are both meshed with the external tooth portion for transmission, and when the main shaft rotates, the moving direction of the first gear is opposite to the moving direction of the second gear;

[0010] The switch assembly includes a control circuit board, an elastic reed, a first trigger and a second trigger. The first trigger is slidably sleeved on the first screw, and the elastic reed is fixedly arranged between the first trigger and the control circuit board. The elastic reed is partially provided with a first contact, and the control circuit board is partially provided with a second contact. When the first gear forces the first trigger to move in a direction close to the elastic reed, the first contact contacts the second contact to control the transmission rod to stop rotating through the control circuit board.

[0011] By adopting the above-mentioned technical solution, the transmission rod connected to the venetian blind motor in the venetian blind can match the plug-in shaft passing through the main shaft, so that the rotation of the transmission rod can drive the main shaft to rotate; when the main shaft rotates, the meshing transmission between the outer tooth portion of the main shaft and the first gear, and the outer tooth portion of the main shaft and the second gear can make the first gear and the second gear move in opposite directions, and then when the venetian blind is rolled up or unrolled to the extreme position, the first gear or the second gear can correspondingly abut against the switch assembly to control the venetian blind motor to stop running.

[0012] Specifically, when the first gear gradually moves and abuts against the first trigger, it can force the first trigger to move in a direction close to the elastic reed; after the first trigger abuts against the elastic reed, it can force the elastic reed to move in a direction close to the control circuit board, and finally the first contact of the elastic reed can contact the second contact of the control circuit board, thereby changing the signal received by the control circuit board, thereby sending a control signal to the venetian blind motor to control the transmission rod to stop rotating.

[0013] Similarly, the second gear also uses this method to control the transmission rod to stop rotating. It can be seen that when the first trigger is against the elastic spring, the lever principle is used to make the first contact contact with the second contact. The moving distance of the first contact can be greater than the moving distance of the first trigger, which has the advantage of sensitive response; and there will be a certain signal response time when the control circuit board sends a signal to the blind motor. During this time period, the first trigger will continue to move toward the direction close to the elastic spring. At this time, the elastic spring can continue to deform inward. The first contact and the second contact are softly connected, which can effectively reduce the friction and scratches between the two, and thus help to maintain a good service life of the limit module.

[0014] Optionally, the switch assembly also includes a first spring, which is arranged between the first trigger and the housing assembly. When the first gear moves away from the first trigger, the first spring forces the first trigger to move away from the elastic spring sheet to separate the first contact from the second contact.

[0015] By adopting the above-mentioned technical solution, the setting of the first spring can always generate an elastic force acting on the first trigger, so that when the first gear moves away from the first trigger, the first spring can force the first trigger to move away from the control circuit board, so as to facilitate the automatic resetting of the limit module.

[0016] Optionally, the elastic spring is provided with an arc-shaped spring, the middle part of which protrudes away from the elastic spring, and one side end of the arc-shaped spring is fixed to the side of the elastic spring close to the control circuit board, and the other side end of the arc-shaped spring abuts against the elastic spring.

[0017] By adopting the above-mentioned technical solution, the setting of the arc-shaped spring sheet can always generate an elastic force acting on the elastic spring sheet, so that after the first trigger leaves the elastic spring sheet, the arc-shaped spring sheet can force the elastic spring sheet to deflect in a direction away from the control circuit board, thereby separating the first contact from the second contact, thereby facilitating the automatic resetting of the limit module.

[0018] Optionally, the limiting module further includes an adjusting component for adjusting the position of the first gear, and the adjusting component is movably arranged at an end of the first screw rod away from the first trigger through a linkage structure;

[0019] The shell assembly includes a shell body and an outer cover plate. The adjusting component is installed inside the shell body, and the adjusting component is partially exposed outside the shell body. The outer cover plate is detachably connected to the shell body and is used to cover the exposed end of the adjusting component.

[0020] By adopting the above-mentioned technical scheme, the lifting stroke of the venetian blind is different according to the size of the venetian blind, and thus the user needs to adjust the relative position of the first gear and the second gear when installing the limiter to adapt to the different lifting strokes of the venetian blind; the present application sets an adjusting component, and after the first screw and the second screw are fixedly installed inside the shell body, the part of the adjusting component exposed to the shell body is forced to rotate, and the linkage structure can drive the corresponding first screw / second screw to rotate, thereby moving the first gear / second gear, so as to facilitate the rapid adjustment of the lifting stroke of the venetian blind.

[0021] Optionally, the linkage structure includes a rectangular portion provided at the end of the first screw rod and a rectangular slot provided in the adjusting component, and the rectangular portion and the rectangular slot are plug-fitted with each other.

[0022] By adopting the above technical solution, through the limiting cooperation between the rectangular part and the rectangular groove, the adjustment component is forced to rotate, which can smoothly drive the corresponding first screw rod / second two to rotate, so as to smoothly adjust the lifting stroke of the blind.

[0023] Optionally, a plum blossom block is provided at one end of the adjusting component away from the first screw rod, and a plum blossom groove is provided inside the outer cover plate. When the outer cover plate is fixed to the shell body, the plum blossom block is matched and clamped in the plum blossom groove.

[0024] By adopting the above-mentioned technical solution, after the stroke adjustment of the venetian blind is completed, the outer cover plate is fixed to the shell body, and the plum blossom block on the adjusting component can be smoothly inserted into the plum blossom groove of the outer cover plate, thereby keeping the first screw / second screw fixed inside the shell assembly, so that the rotation of the main shaft can smoothly drive the first gear / second gear to move along the axial direction of the screw.

[0025] Optionally, a second spring is provided between the adjusting component and the first screw rod, and the second spring is used for forcing the plum blossom block to be normally stuck in the plum blossom groove.

[0026] By adopting the above technical solution, the second spring can always generate elastic force acting on the adjustment component, so that the plum blossom block and the plum blossom groove can maintain the clamping position, so as to facilitate the smooth movement of the first gear / the second gear. In addition, when it is necessary to readjust the lifting stroke of the blind, by removing the outer cover plate, the adjustment component can move outward a certain distance under the elastic force of the second spring, so that the operator can hold the plum blossom block to rotate the adjustment component, thereby improving the convenience of operation.

[0027] In summary, the present application includes at least one of the following beneficial technical effects:

[0028] 1. The first gear of the present application forces the first trigger to move and abut against the elastic spring. When the first trigger abuts against the elastic spring, the first contact point is brought into contact with the second contact point by utilizing the principle of a lever. The moving distance of the first contact point can be greater than the moving distance of the first trigger, which has the advantage of sensitive response.

[0029] 2. When the control circuit board sends a signal to the blind motor, there will be a certain signal response time. During this time period, the first trigger will continue to move towards the direction close to the elastic spring. At this time, the elastic spring can continue to deform inward. The first contact and the second contact are connected in a soft way, which can effectively reduce the friction and scratches between the two, thereby helping to maintain a good service life of the limit module;

[0030] 3. By setting the arc-shaped spring sheet so that it always generates elastic force acting on the elastic spring sheet, after the first trigger leaves the elastic spring sheet, the arc-shaped spring sheet can force the elastic spring sheet to deflect in a direction away from the control circuit board, thereby separating the first contact from the second contact, so as to facilitate the automatic resetting of the limit module. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a partial cross-sectional view of the housing assembly in this embodiment, which mainly reflects the internal overall structure of the limit module;

[0032] Figure 2 is a schematic diagram of the structure of the switch assembly in this embodiment;

[0033] Figure 3 It is a schematic diagram of the assembly structure of the first screw rod, the adjusting component and the outer cover plate in this embodiment.

[0034] Explanation of the accompanying drawings: 1. Shell assembly; 11. Shell body; 111. Retaining wall; 12. Outer cover; 121. Plum blossom groove; 2. Main shaft; 21. External tooth portion; 3. First screw; 31. First gear; 32. Rectangular portion; 4. Second screw; 41. Second gear; 5. Switch assembly; 51. Control circuit board; 511. Second contact; 52. Elastic spring; 521. First contact; 522. Arc-shaped spring; 53. First trigger; 531. Force-applying portion; 54. Second trigger; 55. First spring; 6. Adjustment component; 61. Rectangular slot; 62. Plum blossom block; 7. Second spring; 8. Transmission rod. DETAILED DESCRIPTION

[0035] The following is combined with Figure 1-3 This application is described in further detail.

[0036] The embodiment of the present application discloses a limit module for a venetian blind, which is used to be connected to a venetian blind motor to limit the lifting and lowering of the venetian blind, that is, the venetian blind can stop moving after the venetian blind is fully extended or fully retracted.

[0037] Reference Figure 1 A limit module for a venetian blind includes a shell assembly 1, a main shaft 2, a first screw 3, a second screw 4 and a switch assembly 5, wherein the shell assembly 1 includes a shell body 11 and an outer cover plate 12, and the outer cover plate 12 is detachably fixed to the shell body 11; the main shaft 2 is installed inside the shell body 11 and is freely rotatable, and can rotate circumferentially around its own central axis.

[0038] The main shaft 2 is provided with an axially through-going plug-in slot in a polygonal shape. The output end of the blind motor for controlling the blind lifting is coaxially connected with a transmission rod 8. The shape of the transmission rod 8 is the same as that of the plug-in slot. By matching the transmission rod 8 and plugging it into the plug-in slot, the transmission rod 8 and the main shaft 2 can be circumferentially linked, that is, the rotation of the transmission rod 8 can drive the main shaft 2 to rotate circumferentially. In addition, the outer peripheral side of the main shaft 2 is also provided with an integrally formed external tooth portion 21.

[0039] The first screw 3 and the second screw 4 are both installed inside the shell body 11, and after the outer cover plate 12 is fixed to the shell body 11, the first screw 3 and the second screw 4 can be limited to keep them fixed; the first screw 3 and the second screw 4 are symmetrically arranged on both sides of the main shaft 2.

[0040] The outer circumference of the first screw 3 is sleeved with a first gear 31, and the first gear 31 is connected to the first screw 3 by a thread, and the connection between the two is simply referred to as thread sleeve; the outer circumference of the second screw 4 is also sleeved with a second gear 41 by a thread, and the first gear 31 and the second gear 41 are both meshed with the outer tooth portion 21 for transmission, so that when the main shaft 2 rotates, the first gear 31 can move along the axis direction of the first screw 3, and the second gear 41 can also move along the axis direction of the second screw 4. It should be noted here that by setting the thread rotation direction of the first screw 3 and the second screw 4, the moving direction of the first gear 31 can be opposite to the moving direction of the second gear 41.

[0041] Also refer to Figure 2 The switch assembly 5 includes a control circuit board 51, an elastic spring 52, a first trigger 53, a second trigger 54 and a first spring 55, wherein the control circuit board 51 is fixed inside the shell body 11, and the control circuit board 51 and the outer cover 12 are respectively arranged at both sides of the shell body 11. Figure 2 The first trigger 53 is slidably sleeved on the first screw 3, and the second trigger 54 is slidably sleeved on the second screw 4; there are two elastic springs 52, one of which is arranged between the first trigger 53 and the control circuit board 51, and the other elastic spring 52 is arranged between the second trigger 54 and the control circuit board 51.

[0042] It should be noted that the installation method and function of the first trigger 53 and the second trigger 54 are the same, and the only difference is the installation object. Therefore, the working principle of the first trigger 53 and the corresponding elastic reed 52 is used as an example to explain in detail below, and the working principle of the second trigger 54 and the corresponding elastic reed 52 will not be repeated.

[0043] In addition, after the first screw rod 3 is installed, it abuts against the inner retaining wall 111 of the shell body 11. The first trigger 53 is provided with an integrally formed force-applying portion 531 on the side close to the control circuit board 51. The force-applying portion 531 in this embodiment is configured as a partial ring segment, and the inner retaining wall 111 of the shell body 11 has a through hole for the force-applying portion 531 to pass through, so that the first trigger 53 can only move along the axis direction of the first screw rod 3 and cannot rotate circumferentially. The first spring 55 is disposed between the first trigger 53 and the inner retaining wall 111 of the shell body 11, and the first spring 55 is fixed to the first trigger 53; the first spring 55 can always generate an elastic force acting on the first trigger 53, so that the first trigger 53 is normally spaced apart from the elastic spring sheet 52.

[0044] One side end of the elastic spring 52 is welded and fixed to the control circuit board 51, and the other side end of the elastic spring 52 is provided with a first contact 521, and the first contact 521 is located on a side of the elastic spring 52 close to the control circuit board 51; a second contact 511 is provided on the side of the control circuit board 51 close to the elastic spring 52. When the main shaft 2 rotates and forces the first gear 31 to move along the first screw 3 toward the direction close to the first trigger 53, the first gear 31 abuts against the first trigger 53 and pushes the force-applying part 531 to abut against the elastic spring 52, so that the first contact 521 can contact the second contact 511, thereby causing the control circuit board 51 to receive a signal and change its state, so as to send a control signal to control the blind motor and the transmission rod 8 to stop rotating.

[0045] In addition, the elastic spring 52 is provided with an arc-shaped spring piece 522. In this embodiment, the middle part of the arc-shaped spring piece 522 is protruded in the direction away from the elastic spring piece 52; one end of the arc-shaped spring piece 522 is fixedly connected to the side of the elastic spring piece 52 close to the control circuit board 51, and the other end of the arc-shaped spring piece 522 abuts against the elastic spring piece 52; the arc-shaped spring piece 522 can always generate elastic force acting on the elastic spring piece 52. Therefore, when the first gear 31 moves in the direction away from the first trigger 53, the first spring 55 forces the first trigger 53 to move in the direction away from the elastic spring piece 52, and the arc-shaped spring piece can force the elastic spring piece 52 to move in the direction away from the control circuit board 51, so that the first contact 521 can be separated from the second contact 511 to achieve reset.

[0046] Reference Figure 3The limit module also includes an adjusting component 6 for adjusting the position of the first gear 31. The adjusting component 6 is movably arranged at the end of the first screw 3 away from the first trigger 53 through a linkage structure; specifically, the linkage structure includes a rectangular portion 32 and a rectangular slot 61. The rectangular portion 32 is integrally formed and arranged at the end of the first screw 3 away from the first trigger 53, and the rectangular slot 61 is opened on one side end surface of the adjusting component 6; the rectangular portion 32 and the rectangular slot 61 are plug-fitted and matched. By matching the rectangular portion 32 and inserting it in the rectangular slot 61, rotating the adjusting component 6 can smoothly drive the first screw 3 to rotate, thereby changing the position of the first gear 31.

[0047] Similarly, it can be understood that the second screw rod 4 also controls the position change of the second gear 41 by setting the adjustment component 6. After the relative position of the first gear 31 and the second gear 41 is changed, it can play a role in adjusting the lifting stroke of the blind.

[0048] After the first screw rod 3 and the second screw rod 4 in this embodiment are fixedly installed inside the shell body 11, the adjustment component 6 can be partially exposed outside the shell body 11; the outer cover plate 12 is detachably fixed to the shell body 11 by fastening bolts, and the outer cover plate 12 can cover the exposed end of the adjustment component 6. In addition, two plum blossom grooves 121 are provided inside the outer cover plate 12, and each end face of the adjustment component 6 away from the corresponding first screw rod 3 / corresponding second screw rod 4 is provided with an integrally formed plum blossom block 62, and the plum blossom block 62 is plugged and adapted with the plum blossom groove 121, and after the outer cover plate 12 is fixed to the shell body 11, the plum blossom blocks 62 of the two adjustment components 6 can be correspondingly inserted between the plum blossom grooves 121, so that the first screw rod 3 and the second screw rod 4 remain firmly fixed after installation.

[0049] In addition, a second spring 7 is provided between the first screw rod 3 and the adjusting component 6, one end of the second spring 7 is against the first screw rod 3, and the other end of the second spring 7 is against the adjusting component 6; the second spring 7 can always generate an elastic force acting on the adjusting component 6, so that the plum blossom block 62 is normally stuck in the plum blossom groove 121, so as to ensure the stable positioning of the first screw rod 3 and the second screw rod 4.

[0050] The implementation principle of a limit module for a venetian blind in the embodiment of the present application is as follows:

[0051] When the venetian blind motor is running to drive the main shaft 2 to rotate through the transmission rod 8, the first gear 31 and the second gear 41 can be moved in opposite directions by utilizing the meshing transmission between the outer tooth portion 21 of the main shaft 2 and the first gear 31, and between the outer tooth portion 21 of the main shaft 2 and the second gear 41; when the first gear 31 gradually moves and abuts against the first trigger 53, the first trigger 53 can be forced to move in the direction close to the elastic spring 52; after the first trigger 53 abuts against the elastic spring 52, the elastic spring 52 can be forced to move in the direction close to the control circuit board 51, and finally the first contact 521 of the elastic spring 52 can contact the second contact 511 of the control circuit board 51, thereby changing the signal received by the control circuit board 51, thereby sending a control signal to the venetian blind motor to control the transmission rod 8 to stop rotating; the same is true for the second gear 41, and at this time the venetian blind reaches the limit position of lifting and lowering.

[0052] As can be seen from the above, when the first trigger 53 is against the elastic spring 52, the lever principle is used to make the first contact 521 contact the second contact 511. The moving distance of the first contact 521 can be greater than the moving distance of the first trigger 53, which has the advantage of sensitive response; and there will be a certain signal response time when the control circuit board 51 sends a signal to the blind motor. During this time period, the first trigger 53 will continue to move in the direction close to the elastic spring 52. At this time, the elastic spring 52 can continue to deform inward. The first contact 521 and the second contact 511 are softly connected, which can effectively reduce the friction and scratches between the two, and thus help to keep the limit module in a good service life.

[0053] The above are preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A limit module for a venetian blind, characterized in that: The invention comprises a housing assembly (1), a main shaft (2), a first screw rod (3), a second screw rod (4) and a switch assembly (5), wherein the main shaft (2) is rotatably mounted inside the housing assembly (1), and the first screw rod (3) and the second screw rod (4) are both fixedly mounted inside the housing assembly (1) and are arranged on both sides of the main shaft (2); The main shaft (2) is provided with a plug-in slot for plugging a transmission rod (8), the main shaft (2) and the transmission rod (8) are arranged in a circumferential linkage, and the outer peripheral surface of the main shaft (2) is provided with an external tooth portion (21); a first gear (31) is provided on the outer peripheral side of the first screw rod (3), and a second gear (41) is provided on the outer peripheral side of the second screw rod (4), the first gear (31) and the second gear (41) are both meshed with the external tooth portion (21) for transmission, and when the main shaft (2) rotates, the movement direction of the first gear (31) is opposite to the movement direction of the second gear (41); The switch assembly (5) comprises a control circuit board (51), an elastic spring (52), a first trigger (53) and a second trigger (54); the first trigger (53) is slidably sleeved on the first screw rod (3); the elastic spring (52) is fixedly arranged between the first trigger (53) and the control circuit board (51); a first contact point (521) is partially provided on the elastic spring (52); a second contact point (511) is partially provided on the control circuit board (51); when the first gear (31) forces the first trigger (53) to move in a direction close to the elastic spring (52), the first contact point (521) contacts the second contact point (511), so as to control the transmission rod (8) to stop rotating through the control circuit board (51).

2. The position limiting module for venetian blinds according to claim 1, characterized in that: The switch assembly (5) further comprises a first spring (55), wherein the first spring (55) is arranged between the first trigger (53) and the housing assembly (1); when the first gear (31) moves in a direction away from the first trigger (53), the first spring (55) forces the first trigger (53) to move in a direction away from the elastic spring sheet (52), so that the first contact point (521) is separated from the second contact point (511).

3. The position limiting module for venetian blinds according to claim 1, characterized in that: The elastic spring (52) is provided with an arc-shaped spring (522), the middle portion of the arc-shaped spring (522) is arranged to protrude in a direction away from the elastic spring (52), one side end of the arc-shaped spring (522) is fixed to a side surface of the elastic spring (52) close to the control circuit board (51), and the other side end of the arc-shaped spring (522) is in contact with the elastic spring (52).

4. The limiting module for venetian blinds according to claim 3 is characterized in that: It also includes an adjusting component (6) for adjusting the position of the first gear (31), wherein the adjusting component (6) is movably arranged at an end of the first screw rod (3) away from the first trigger (53) through a linkage structure; The housing assembly (1) comprises a housing body (11) and an outer cover plate (12); the adjusting component (6) is installed inside the housing body (11), and the adjusting component (6) is partially exposed outside the housing body (11); the outer cover plate (12) is detachably connected to the housing body (11) and is used to cover the exposed end of the adjusting component (6).

5. The position limiting module for venetian blinds according to claim 4, characterized in that: The linkage structure comprises a rectangular portion (32) provided at the end of the first screw rod (3) and a rectangular slot (61) provided in the adjustment component (6), and the rectangular portion (32) and the rectangular slot (61) are plug-fitted and matched.

6. The limiting module for venetian blinds according to claim 4, characterized in that: A plum blossom block (62) is provided at one end of the adjustment component (6) away from the first screw rod (3), and a plum blossom groove (121) is provided inside the outer cover plate (12). When the outer cover plate (12) is fixed to the shell body (11), the plum blossom block (62) is matched and clamped in the plum blossom groove (121).

7. The limiting module for venetian blinds according to claim 6, characterized in that: A second spring (7) is provided between the adjusting component (6) and the first screw rod (3), and the second spring (7) is used to force the plum blossom block (62) to be normally locked in the plum blossom groove (121).

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