Electric downtilt adjustment device and base station antenna

Abstract

The application relates to the technical field of antennas, in particular to an electric downtilt angle adjusting device and a base station antenna. The electric downtilt angle adjusting device comprises a position selection transmission assembly and a phase shift assembly. The position selection transmission assembly comprises a support frame, a moving switching mechanism, a transmission gear and a second guide shaft. The second guide shaft is installed on the support frame, a plurality of transmission intermediate gears are installed on the second guide shaft at intervals, the transmission gear is used for driving the transmission intermediate gears to rotate, the moving switching mechanism is installed on the support frame and is used for driving the transmission gear to move and switch among the plurality of transmission intermediate gears. A driving piece is arranged on the moving switching mechanism and is used for driving the transmission gear to rotate. The phase shift assembly comprises a plurality of driven pieces which are respectively used for being connected with corresponding phase shifters to realize the adjustment of the tilt angle of the phase shifters. The electric downtilt angle adjusting device provided by the application has the advantages of simple structure, convenient manufacturing, low cost, light weight, small size and reliable quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of antenna, in particular to an electric downtilt angle adjusting device and a base station antenna. BACKGROUND

[0002] The base station antenna needs to be tilted downward relative to the horizontal line by a certain angle when working, and the size of the tilt angle can change the radiation range of the antenna. At present, the adjustment of the downtilt angle of the antenna mainly includes mechanical downtilt angle and electric downtilt angle. The electric downtilt angle can be controlled remotely and has low cost, so it is more and more widely used.

[0003] With the continuous increase in the number of mobile communication terminal users, the same antenna often needs to have more communication frequency bands, and the electric downtilt angle of each communication frequency band needs to be controlled independently, and the change of the electric downtilt angle is realized by driving the corresponding phase shifter transmission mechanism. In the traditional transmission device, one driving motor is usually used to correspond to one phase shifter transmission mechanism. Due to the large number of control circuits and motors, this method inevitably causes high cost, complex structure, large space occupation and low reliability. SUMMARY

[0004] The purpose of the present application is to provide an antenna electric downtilt angle adjusting device which is simple in structure, convenient to manufacture, low in cost, light in weight, small in size and reliable in quality, and a base station antenna using the antenna electric downtilt angle adjusting device.

[0005] In order to achieve the purpose of the present application, the following technical solutions are adopted:

[0006] The first aspect of the present application provides an electric downtilt angle adjusting device, which comprises a position selection transmission assembly and a phase shifting assembly. The position selection transmission assembly comprises a support frame, a moving switching mechanism, a transmission gear and a second guide shaft. The second guide shaft is installed on the support frame, and a plurality of transmission intermediate gears are installed on the second guide shaft at intervals. The transmission gear is used to drive the transmission intermediate gears to rotate. The moving switching mechanism is installed on the support frame and is used to drive the transmission gear to move and switch among the plurality of transmission intermediate gears. A driving member is arranged on the moving switching mechanism, and the driving member is used to drive the transmission gear to rotate.

[0007] The phase shifting assembly comprises a plurality of driven members. The plurality of transmission intermediate gears are respectively and one-to-one correspondingly connected with the plurality of driven members in transmission. The plurality of driven members are respectively used to connect with corresponding phase shifters to realize the adjustment of the tilt angle of the phase shifters.

[0008] Further improvement lies in that the mobile switching mechanism comprises a transmission shaft and a position selecting rack, the position selecting rack is provided with position selecting fixing holes at both ends, transmission gears are installed at the position selecting fixing holes at both ends respectively, the transmission shaft passes through the holes of the position selecting fixing holes and the transmission gears and is connected with the support frames at both ends respectively, a position selecting input gear is arranged on the position selecting rack, and rotation of the position selecting input gear can drive the position selecting rack and the transmission gears to slide along the axial direction of the transmission shaft.

[0009] Further improvement lies in that a round shaft elastic arm is arranged on the transmission gear, the round shaft elastic arm can rotate in the position selecting fixing hole of the position selecting rack, and the end of the transmission gear is provided with a reverse buckle which is buckled on the position selecting fixing hole.

[0010] Further improvement lies in that the driving member comprises a transmission input bevel gear and a first bevel gear, the first bevel gear is sleeved on the transmission shaft, rotation of the first bevel gear can drive the transmission shaft and the transmission gear to rotate synchronously, and rotation of the transmission input bevel gear can drive the first bevel gear to rotate.

[0011] Further improvement lies in that a plurality of clamping grooves are arranged on the second guide shaft, a clamping ring is arranged on the stop surface of the transmission intermediate gear, and the second guide shaft passes through the holes of the plurality of transmission intermediate gears in sequence and then the clamping ring is buckled in the corresponding clamping groove on the second guide shaft.

[0012] Further improvement lies in that the phase shifting assembly comprises a fixed seat on one side of the position selecting transmission assembly, the driven member comprises an inner threaded strip and an outer threaded column, the inner threaded strip is installed in the guide groove of the fixed seat, the outer threaded column is arranged below the inner threaded strip, rotation of the transmission intermediate gear can drive the outer threaded column to rotate, and rotation of the outer threaded column can drive the inner threaded strip to slide in the guide groove.

[0013] Further improvement lies in that the driven member further comprises a third bevel gear, a second bevel gear is arranged on the transmission intermediate gear, the second bevel gear is meshingly connected with the corresponding third bevel gear, the third bevel gear passes through the first circular hole of the fixed seat, the through hole of the outer threaded column and the second circular hole of the fixed seat in sequence, and the third bevel gear is in drivable connection with the outer threaded column, and the third bevel gear can rotate in the first circular hole and the second circular hole of the fixed seat.

[0014] Further improvement lies in that a damping ring is arranged between the third bevel gear and the first circular hole of the fixed seat.

[0015] Further improvement lies in that a spring buckle is arranged at the rear of the third bevel gear, the spring buckle is buckled on the end surface of the second circular hole of the fixed seat, and the spring buckle is used for preventing the third bevel gear from being loosened from the fixed seat.

[0016] The second aspect of the present application provides a base station antenna, which comprises an electrical downtilt angle adjustment device as claimed in any one of the first aspects.

[0017] Advantages of the present application:

[0018] The transmission input bevel gear rotates to drive the rotation of the first bevel gear, thereby driving the synchronous rotation of the transmission shaft and the transmission gear. The rotation of the transmission gear drives the rotation of the transmission intermediate gear which is engaged with the second bevel gear and the third bevel gear. The transmission intermediate gear is fixed along the axis of the second guide shaft and can only rotate along the axis of the second guide shaft under the action of the snap ring. The rotation of the transmission intermediate gear drives the rotation of the third bevel gear, thereby driving the forward and backward movement of the internal threaded strip in the guide groove. The end of the internal threaded strip can be connected with the corresponding phase shifter, thereby achieving the adjustment of the inclination angle of the phase shifter.

[0019] The electrical downtilt angle adjustment device has the advantages of simple structure, convenient manufacturing, low cost, light weight, small size, and reliable quality.

[0020] The anti-unhooking hook is arranged on the support frame, the two ends of the transmission shaft are provided with ring grooves, the anti-unhooking hook of the support frame is clamped into the ring grooves of the transmission shaft, the support frame can be prevented from falling off, the position selection transmission assembly forms an integral whole, and the position selection transmission assembly is convenient for turnover and installation as a module on a production line.

[0021] The damping ring is arranged between the third bevel gear and the first circular hole of the fixed seat, the forward and backward sliding of the internal threaded strip caused by the shaking of the third bevel gear in a non-working state, such as during product transportation, is prevented, the elastic buckle is arranged and clamped on the end face of the second circular hole of the fixed seat, the third bevel gear can be prevented from being loosened from the fixed seat, the phase shifting assembly forms an integral whole, and the phase shifting assembly is convenient for turnover and installation as a module on a production line. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The electrical downtilt angle adjustment device Figure 1 ;

[0023] Figure 2 The position selection transmission assembly of the electrical downtilt angle adjustment device

[0024] Figure 3 The transmission intermediate gear assembly of the electrical downtilt angle adjustment device

[0025] Figure 4 A selection transmission assembly structure diagram of an electric downtilt angle adjustment device according to an embodiment of the present application;

[0026] Figure 5 An exploded diagram of a phase shifting assembly of an electric downtilt angle adjustment device according to an embodiment of the present application;

[0027] Figure 6 A cross-sectional view of a phase shifting assembly of an electric downtilt angle adjustment device according to an embodiment of the present application;

[0028] Figure 7 A structure diagram of an electric downtilt angle adjustment device according to an embodiment of the present application Figure 2 .

[0029] BRIEF DESCRIPTION OF THE DRAWINGS

[0030] 1, selection transmission assembly; 2, phase shifting assembly; 10, selection input gear; 11, transmission input bevel gear; 12, support frame; 13, selection rack; 14, transmission gear; 141, round shaft elastic arm; 142, reverse buckle; 15, transmission shaft; 16, first bevel gear; 17, first guide shaft; 18, transmission intermediate gear; 181, second bevel gear; 182, retreat stop surface; 19, second guide shaft; 191, clamping groove; 20, clamping ring; 21, fixed seat; 211, first round hole; 212, second round hole; 22, third bevel gear; 221, elastic buckle; 23, external thread column; 24, internal thread strip; 25, damping ring. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be further described in detail below with reference to the drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the protection scope of the present application.

[0032] It should be noted that when an element is referred to as "fixed to", "provided on", "fixed on" or "arranged on" another element, it can be directly on the other element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be a middle element. Further, when an element is considered to be "transmission connected" to another element, the two can achieve power transmission, and the specific implementation can use existing technology, which will not be described here. When an element is perpendicular or approximately perpendicular to another element, it means that the ideal state of the two is perpendicular, but due to manufacturing and assembly, there can be a certain vertical error. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for illustrative purposes and do not represent the only implementation.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0034] The "first", "second" involved in the present application does not represent the specific number and order, just for the name of the distinction.

[0035] The specific embodiments of the present application will be described below with reference to the accompanying drawings. Figure 1 - the accompanying drawings Figure 7 The specific embodiments of the present application will be described below with reference to the accompanying drawings.

[0036] The first aspect of the present application provides an electric downtilt angle adjustment device, with reference to the accompanying drawings Figure 1 The application scheme of the present application consists of the following components:

[0037] The electric downtilt angle adjustment device comprises a position selection transmission assembly 1 and a phase shift assembly 2. The position selection transmission assembly 1 can complete the position selection of any transmission in the phase shift assembly 2. The phase shift assembly 2 can drive the corresponding phase shifter (not shown) to adjust the tilt angle. The position selection transmission assembly 1 comprises a support frame 12, a moving switching mechanism, a transmission gear 14 and a second guide shaft 19. The second guide shaft 19 is installed on the support frame 12. A plurality of transmission intermediate wheels 18 are installed on the second guide shaft 19 at intervals. The transmission gear 14 is used to drive the transmission intermediate wheel 18 to rotate. The moving switching mechanism is installed on the support frame 12 and is used to drive the transmission gear 14 to move and switch among the plurality of transmission intermediate wheels 18. A driving member is arranged on the moving switching mechanism. The driving member is used to drive the transmission gear 14 to rotate.

[0038] The phase shift assembly 2 comprises a plurality of driven members. The plurality of transmission intermediate wheels 18 are respectively and correspondingly connected in transmission with the plurality of driven members. The plurality of driven members are respectively connected with the corresponding phase shifters for adjusting the tilt angle of the phase shifters.

[0039] The moving switching mechanism comprises a transmission shaft 15 and a position selection rack 13. Position selection fixing holes 131 are arranged at both ends of the position selection rack 13. Transmission gears 14 are installed in the position selection fixing holes 131 at both ends. The transmission shaft 15 passes through the position selection fixing holes 131 and the holes of the transmission gears 14 and is connected with the support frame 12 at both ends. A position selection input gear 10 is arranged on the position selection rack 13. The rotation of the position selection input gear 10 can drive the position selection rack 13 and the transmission gear 14 to slide along the axial direction of the transmission shaft 15.

[0040] The driving member comprises a transmission input bevel gear 11 and a first bevel gear 16 sleeved on a transmission shaft 15, rotation of the first bevel gear 16 can drive the transmission shaft 15 and the transmission gear 14 to rotate synchronously, and rotation of the transmission input bevel gear 11 can drive the first bevel gear 16 to rotate.

[0041] Specifically, referring to the accompanying drawings Figure 2 As shown in the drawings, the transmission gear 14 is symmetrically installed on the position fixing holes 131 at both ends of the position rack 13, the transmission gear 14 is provided with a circular shaft elastic arm 141, the circular shaft elastic arm 141 of the transmission gear 14 can rotate in the position fixing hole 131 of the position rack 13, and the end of the transmission gear 14 is provided with a reverse buckle 142 which can be buckled on the position fixing hole 131.

[0042] Further, the transmission shaft 15 passes through the holes of the transmission gear 14, the first bevel gear 16 and the other transmission gear 14, and the transmission shaft 15 and the transmission gear 14 and the first bevel gear 16 can be matched by using a spline structure, so that the rotation of the first bevel gear 16 can drive the transmission shaft 15 and the transmission gear 14 to rotate synchronously.

[0043] Further, the support frame 12 is further provided with a first guide shaft 17 which passes through both ends of the position rack 13, the position rack 13 can drive the transmission gear 14 buckled on the position fixing hole 131 to freely slide along the axial direction of the transmission shaft 15 (or the first guide shaft 17) as a whole, and through the joint action of the first guide shaft 17 and the transmission shaft 15, the sliding of the position rack 13 is more stable.

[0044] Referring to Figure 3 As shown in the drawings, the second guide shaft 19 is provided with a plurality of clamping grooves 191, the stop surface 182 of the transmission intermediate gear 18 is provided with a clamping ring 20, the second guide shaft 19 passes through the holes of the transmission intermediate gear 18 in sequence, and then the clamping ring 20 is buckled in the corresponding clamping groove 191 of the second guide shaft 19, so that the transmission intermediate gears 18 are evenly and symmetrically distributed on both sides of the second guide shaft 19. The transmission intermediate gear 18 can freely rotate along the axis of the first guide shaft 17, and the clamping ring 20 is arranged on the stop surface 182 of the transmission intermediate gear 18 to prevent the transmission intermediate gear 18 from sliding to the other side along the axial direction of the second guide shaft 19. Further, the installation position and the number of the clamping ring 20 and the transmission intermediate gear 18 can be adjusted according to the realization of the antenna, and the embodiment of the present application adopts 12 paths for illustration.

[0045] Referring to Figure 4 As shown in the drawings, the support frame 12 is installed at both ends of the first guide shaft 17, the second guide shaft 19 and the transmission shaft 15, and plays a role of supporting and positioning the first guide shaft 17, the second guide shaft 19 and the transmission shaft 15.

[0046] Further, the transmission shaft 15 can rotate freely in the fixed holes at both ends of the support frame 12, the support frame 12 is provided with an anti-unhooking hook 121, the transmission shaft 15 is provided with a ring groove 151 at both ends, the anti-unhooking hook 121 of the support frame 12 is clamped into the ring groove 151 of the transmission shaft 15, which can prevent the support frame 12 from falling off, so that the position selection transmission assembly 1 forms a whole, and the position selection transmission assembly 1 is convenient as a module to circulate and install on the production line.

[0047] Further, the rotation of the position selection input gear 10 can drive the position selection rack 13 to slide along the shaft direction of the transmission shaft 15 (or the first guide shaft 17), the sliding of the position selection rack 13 can drive the transmission gear 14 buckled on the position selection fixed hole 131 to move correspondingly, and in the process of sliding of the position selection rack 13, the transmission gear 14 can be engaged with the transmission intermediate gear 18 fixed on the second guide shaft 19 one by one, so as to complete the position selection of different position transmission intermediate gears 18.

[0048] Further, the number of transmission gears 14 can be designed as one or several according to the efficiency requirement of gear shifting (the number of transmission gears 14 in the example is 2), when one of the transmission gears 14 is engaged with any transmission intermediate gear 18, the transmission gears 14 at other positions need to be completely separated from the transmission intermediate gears 18.

[0049] Referring to Figure 5 and the accompanying Figure 6 , the phase shift assembly 2 includes a fixed seat 21 on one side of the position selection transmission assembly 1, the driven part includes an inner threaded strip 24 and an outer threaded column 23, the inner threaded strip 24 is installed in the guide groove of the fixed seat 21, the inner threaded strip 24 can slide freely in the guide groove, the outer threaded column 23 is placed below the inner threaded strip 24, and the outer threaded column 23 and the inner threaded strip 24 can adopt other transmission modes such as worm gears and screw rods in addition to the threaded transmission mode shown in the example. The rotation of the transmission intermediate gear 18 can drive the outer threaded column 23 to rotate, and the rotation of the outer threaded column 23 can drive the inner threaded strip 24 to slide in the guide groove.

[0050] Further, the driven member further comprises a third bevel gear 22, the transmission intermediate wheel 18 is provided with a second bevel gear 181, the second bevel gear 181 is in meshing connection with the corresponding third bevel gear 22, the third bevel gear 22 is provided with a damping ring 25 between the first circular hole 211 of the fixed seat 21, the third bevel gear 22 passes through the damping ring 25, the first circular hole 211 of the fixed seat 21, the through hole of the outer threaded column 23 and the second circular hole 212 of the fixed seat 21 in sequence, and the third bevel gear 22 is in driving connection with the outer threaded column 23, specifically, the third bevel gear 22 and the outer threaded column 23 can be in driving connection through the structure cooperation of the spline, the third bevel gear 22 can rotate freely in the first circular hole 211 and the second circular hole 212 of the fixed seat 21, the rotation of the third bevel gear 22 can drive the outer threaded column 23 to rotate, and the rotation of the outer threaded column 23 can drive the inner threaded strip 24 to move forward and backward in the guide groove of the fixed seat 21.

[0051] The damping ring 25 is arranged between the third bevel gear 22 and the first circular hole 211 of the fixed seat 21, so that the third bevel gear 22 is prevented from shaking and causing the forward and backward sliding of the inner threaded strip 24 in the non-working state, such as the product transportation process.

[0052] Preferably, the rear part of the third bevel gear 22 can be further designed as a spring buckle 221, the spring buckle 221 is buckled on the end face of the second circular hole 212 of the fixed seat 21, which is used for preventing the third bevel gear 22 from being loosened from the fixed seat 21, so that the phase shift assembly 2 forms an integral whole, and the phase shift assembly 2 is convenient to circulate and install as a module on the production line.

[0053] The working principle of the present application is as follows: since the transmission shaft 15 passes through the holes of the transmission gear 14 and the first bevel gear 16, and the holes of the transmission shaft 15 and the first bevel gear 16 and the transmission gear 14 are in spline connection, the rotation of the transmission input bevel gear 11 can drive the rotation of the first bevel gear 16, thereby driving the synchronous rotation of the transmission shaft 15 and the transmission gear 14. The rotation of the transmission gear 14 can drive the rotation of a certain transmission intermediate wheel 18 in meshing connection therewith. Further, since the second bevel gear 181 of the transmission intermediate wheel 18 is in meshing connection with the third bevel gear 22, and the transmission intermediate wheel 18 is fixed along the axial direction of the second guide shaft 19 under the action of the clasp 20, the transmission intermediate wheel 18 can only rotate along the axis of the second guide shaft 19, and the rotation of the transmission intermediate wheel 18 can drive the rotation of the third bevel gear 22, thereby driving the forward and backward movement of the inner threaded strip 24 in the guide groove, the end part of the inner threaded strip 24 can be connected with the corresponding phase shifter (not shown), thereby realizing the adjustment of the inclination angle of the phase shifter (not shown).

[0054] Reference Figure 7As shown, in some other embodiments of the present application, the phase shift component 2 can be designed as one or more groups (two groups are used in this example), and according to the actual needs of the antenna, the phase shift component 2, the transmission intermediate wheel 18 and the snap ring 20 can be increased or decreased accordingly to realize the modularization of the product, improve the applicability of the product and save the cost.

[0055] The second aspect embodiment of the present application provides a base station antenna, which comprises the electric downtilt angle adjustment device as described in any of the first aspect embodiments above. Since the other parts of the base station antenna are of the prior art, those skilled in the art can realize them by referring to the prior art, and thus the present embodiment will not be described in detail here.

[0056] The technical features of the above embodiments can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the present application.

[0057] The above embodiments only express the specific implementation of the present application, and the description is more specific and detailed, but it should not be considered as a limitation to the scope of the present application. It should be pointed out that for those skilled in the art, without departing from the concept of the present application, some modifications and improvements can be made, which are all within the protection of the present application.

Claims

1. An electric downtilt adjustment device, comprising a positioning transmission assembly and a phase shifting assembly, characterized in that, The positioning transmission assembly includes a support frame, a moving switching mechanism, a transmission gear, and a second guide shaft. The second guide shaft is mounted on the support frame, and a plurality of transmission intermediate wheels are spaced apart on the second guide shaft. The transmission gear drives the transmission intermediate wheels to rotate. The moving switching mechanism is mounted on the support frame and drives the transmission gear to move and switch among the plurality of transmission intermediate wheels. A driving component is provided on the moving switching mechanism, and the driving component drives the transmission gear to rotate. The second guide shaft is provided with a plurality of slots, and the anti-reverse surface of the transmission wheel is provided with a retaining ring. After the second guide shaft passes through the holes of the plurality of transmission wheels one by one, it is then secured in the corresponding slot on the second guide shaft with a retaining ring. The transmission wheel can rotate freely along the axis of the first guide shaft, and the retaining ring is placed on the anti-reverse surface of the transmission wheel to prevent the transmission wheel from sliding along the axial direction of the second guide shaft. The phase shifting assembly includes several driven members, several transmission wheels are respectively connected to several driven members in a one-to-one transmission connection, and several driven members are respectively used to connect with corresponding phase shifters to realize the adjustment of the tilt angle of the phase shifter; The phase-shifting assembly includes a fixed base located on one side of the positioning transmission assembly. The driven member includes an internal threaded strip and an external threaded post. The internal threaded strip is installed in the guide groove of the fixed base, and the external threaded post is placed below the internal threaded strip. The rotation of the transmission wheel can drive the external threaded post to rotate, and the rotation of the external threaded post can drive the internal threaded strip to slide in the guide groove. The driven component also includes a third bevel gear, and a second bevel gear is provided on the transmission intermediate wheel. The second bevel gear meshes with the corresponding third bevel gear. The third bevel gear passes sequentially through the first circular hole of the fixed seat, the through hole of the external threaded column, and the second circular hole of the fixed seat. The third bevel gear and the external threaded column are connected in a driveable manner. The third bevel gear can rotate within the first and second circular holes of the fixed seat. A damping ring is provided between the third bevel gear and the first circular hole of the fixed seat to prevent the third bevel gear from vibrating and causing the internal threaded strip to slide back and forth when it is not in operation. A spring buckle is provided at the rear of the third bevel gear. The spring buckle is locked onto the end face of the second circular hole of the fixed seat to prevent the third bevel gear from coming loose from the fixed seat.

2. The electric tilt angle adjustment device according to claim 1, characterized in that, The moving switching mechanism includes a drive shaft and a selection rack. The selection rack has selection fixing holes at both ends, and a drive gear is installed in each of the selection fixing holes. The drive shaft passes through the selection fixing holes and the holes of the drive gears and is connected to the support frame at both ends. The selection rack is provided with a selection input gear. The rotation of the selection input gear can drive the selection rack and the drive gear to slide along the axial direction of the drive shaft.

3. The electric tilt angle adjustment device according to claim 2, characterized in that, The transmission gear is provided with a round shaft spring arm, which can rotate within the positioning fixing hole of the positioning rack, and the end of the transmission gear is provided with a buckle, which is snapped onto the positioning fixing hole.

4. The electric tilt angle adjustment device according to claim 2, characterized in that, The driving component includes a transmission input bevel gear and a first bevel gear. The first bevel gear is sleeved on the transmission shaft. The rotation of the first bevel gear can drive the transmission shaft and the transmission gear to rotate synchronously. The rotation of the transmission input bevel gear can drive the first bevel gear to rotate.

5. A base station antenna, characterized in that, Includes an electric downtilt adjustment device as described in any one of claims 1-4.

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