A solar tracker

Abstract

The present invention discloses a solar tracker, comprising a main beam and at least one slewing reducer, wherein one slewing reducer is connected to a motor, the motor is controlled by a motor controller, and the motor controller and the motor are connected by a cable; the main beam is passed through the inside of the slewing reducer. In the present invention, the main beam passes through the middle of the reducer, so the length of the main beam can be longer, the joints between the main beams can be effectively reduced, the rigidity and strength of the entire bracket are increased, and the risk is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of solar power generation, and in particular relates to a solar tracker. Background Art

[0002] The share of solar photovoltaic power generation in the electricity market is increasing rapidly, and the market prospects are extremely promising. The use of tracking power generation systems in large commercial power stations can increase the power generation of power stations by more than 20% compared to fixed power generation systems. Therefore, there will be more and more commercial power stations using tracking power generation in the future, and more requirements will be put forward for single-beam multi-point drive solar tracking power generation systems (tracking brackets). The current mainstream flat single-axis or inclined single-axis tracking power generation systems in the market have increasingly larger installed power due to the increase in component power, and their structural shortcomings are becoming increasingly obvious. They are gradually unable to adapt to the higher and more usage requirements of trackers in the future. At present, in the existing tracking transmission system, the main beam cannot be installed or the length is insufficient due to the error in the size of the column caused by the foundation construction. Summary of the invention

[0003] In order to overcome the deficiencies of the prior art, the present invention provides a solar tracker.

[0004] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: A tracking drive transmission mechanism for multi-point driven flat single axis, comprising a main beam and at least one slewing reducer, wherein one slewing reducer is connected to a motor, the motor is controlled by a motor controller, and the motor controller and the motor are connected by a cable; the slewing reducer connected to the motor is an active slewing reducer, and the other slewing reducers are driven slewing reducers, the torque of the active slewing reducer is transmitted to the driven slewing reducer through a transmission shaft, the active slewing reducer and the driven slewing reducer rotate synchronously, thereby driving the main beam to rotate.

[0005] In the tracking power generation system, the stability of the transmission shaft is the basis for the stability of the entire tracking system. During the long-term movement of the transmission shaft, the large span of the two column brackets of the multi-point drive tracking bracket will cause the transmission shaft to sag and cause deformation. The first aspect of the present invention is to provide a solar tracking system with stable torque transmission.

[0006] Optionally, a plurality of connecting members are spaced apart along the length direction of the transmission shaft, and the connecting members are connected to the main beam via a slide rail, and the connecting members can slide on the slide rail.

[0007] Optionally, the connecting member slides outside the slide rail.

[0008] Optionally, the connecting member is provided with a sliding ring, and the sliding ring is sleeved on the outside of the slide rail.

[0009] Optionally, the connecting member slides in the slide rail.

[0010] Optionally, an annular slide is provided outside the connecting piece, an annular groove matching the annular slide is provided inside the slide rail, and the annular slide can slide in the annular groove.

[0011] Optionally, the slide rail is arranged in an arc shape, and a frame body having the same shape as the main beam is provided on the slide rail, and the main beam is passed through the frame body.

[0012] Optionally, the rotary reducer is a worm gear reducer, a transmission gear is provided on the outside of one end of the worm, a first bevel gear is provided at the output end of the motor, the transmission shaft is connected to the output end of the motor, and the transmission gear is matched with the first bevel gear through a bevel gear group.

[0013] Optionally, the bevel gear set includes a second bevel gear meshing with the first bevel gear, a transfer gear arranged on one side of the first bevel gear, and a rotating shaft for connecting the second bevel gear and the transfer gear.

[0014] Optionally, both ends of the worm wheel are connected to the main beam via a connecting assembly, and the connecting assembly includes a circular disc, a square shaft, and a connecting column arranged between the circular disc and the square shaft.

[0015] Optionally, the square shaft is arranged at an eccentric position relative to the disc, the disc is provided with a first positioning hole, the worm gear is provided with a second positioning hole, and the first positioning hole is anti-rotatably matched with the second positioning hole through a locking piece.

[0016] In the solar tracking system, due to the foundation construction, the column size error causes the main beam to be unable to be installed or the length is insufficient. The second aspect of the present invention aims to provide a multi-point drive tracking transmission system with controllable main beam length.

[0017] Optionally, the main beam is passed through the interior of the slewing reducer.

[0018] Optionally, a rotating shaft is sleeved on the outside of the main beam, and the rotating shaft cooperates with the worm gear through a rolling bearing.

[0019] Optionally, the main beam is connected to the rotating shaft and the outer shell through a locking member.

[0020] Optionally, the locking member is provided with a convex ring extending outward in the axial direction, the outer wall of the convex ring is a first inclined surface structure arranged from top to bottom, the inner walls of the rotating shaft and the rotating reduction housing are both a second inclined surface structure arranged from bottom to top, and the first inclined surface can move left and right along the second inclined surface.

[0021] Optionally, the locking piece is provided with a frustum of cone extending outward in the radial direction, a first locking hole is formed on the frustum of cone, a second locking hole is formed on the outer shell of the rotary shaft and the rotary reducer, and the first locking hole is anti-rotatably engaged with the second locking hole through the locking piece.

[0022] Optionally, the outer wall of the locking member is provided with a first inclined surface structure from top to bottom, the inner wall of the rotating shaft is circumferentially provided with a plurality of reinforcing ribs extending inward, the inner wall of the reinforcing rib is provided with a second inclined surface structure from bottom to top, and the first inclined surface can move left and right along the second inclined surface.

[0023] Optionally, the locking member is provided with a boss extending outward in the radial direction, the boss is provided with a first locking hole, the rotary shaft and the outer shell of the rotary reducer are both provided with a second locking hole, and the first locking hole is anti-rotationally engaged with the second locking hole through the locking member.

[0024] Optionally, the shape of the inner wall of the locking member is the same as the shape of the outer wall of the main beam.

[0025] Compared with the prior art, the present invention has the following advantages: 1. The span between the two uprights of the multi-point drive tracking connector is large, which solves the problem of deformation of the transmission shaft caused by sagging, solves the problem of rotation oscillation caused by the bending of the transmission shaft, and solves the problem of discontinuous rotation caused by the sagging deformation of the transmission shaft;

[0026] 2. Through the setting of the slide rail and the connecting parts, the main beam drives the transmission shaft sliding ring to rotate; the rotation of the main beam and the rotation of the transmission shaft do not interfere with each other, and both can rotate freely within a limited range;

[0027] 3. Through the eccentric setting, the design size of one end connected to the worm gear is smaller, which can avoid the installation interference of the connecting bolts, and the design size of the other end is larger, which can match the main beam of larger size;

[0028] 4. The main beam passes through the middle of the reducer, so the length of the main beam can be longer, which can effectively reduce the joints between the main beams, increase the rigidity and strength of the entire column bracket, and reduce risks;

[0029] 5. The inner ring of the locking piece is set to the same shape as the main beam to ensure the connection rigidity between the torque tube and the reducer;

[0030] 6. Through the arrangement of the first inclined surface and the second inclined surface, when the locking piece moves, the locking piece will shrink and exert radial pressure on the main beam, thereby achieving the effect of locking the torque tube of the main beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the present invention.

[0032] Figure 2 It is a schematic diagram of the explosion structure of the rotary reducer of the present invention.

[0033] Figure 3 It is the left side view of the rotary reducer of the present invention.

[0034] Figure 4 for Figure 3 A sectional stereogram taken along AA in the middle.

[0035] Figure 5 for Figure 3 A schematic diagram of the enlarged structure in the middle.

[0036] Figure 6 The partial cross-section diagram of the rotary reducer of the present invention is shown in FIG. Figure 1 .

[0037] Figure 7 The partial cross-section diagram of the rotary reducer of the present invention is shown in FIG. Figure 2 .

[0038] Figure 8 The partial cross-section diagram of the rotary reducer of the present invention is shown in FIG. Figure 3 .

[0039] Fig. 9 It is a schematic diagram of the structure of the connection assembly of the present invention.

[0040] Fig.10 It is a schematic diagram of the worm gear structure of the present invention.

[0041] Fig.11 This is a schematic structural diagram of a second embodiment of the present invention.

[0042] Fig.12 A partial cross-sectional view of a second embodiment of the present invention Figure 1 .

[0043] Fig.13 This is a schematic diagram of the structure in which the main beam of the present invention is arranged.

[0044] Fig.14 This is a schematic diagram of the explosion structure of the slewing reducer included in the main beam of the present invention.

[0045] Fig.15 The schematic diagram of the partial section of the rotary reducer disposed in the main beam of the present invention Figure 1 .

[0046] Fig.16 The schematic diagram of the partial section of the rotary reducer disposed in the main beam of the present invention Figure 2 .

[0047] Fig.17 for Fig.16 Enlarged schematic diagram of the structure at point B in the middle.

[0048] Fig.18 Schematic diagram of the locking structure set in the main beam.

[0049] Fig.19 Schematic diagram of the rotary axis structure including the main beam.

[0050] Fig. 20 A schematic structural diagram of a second implementation method including a main beam arrangement.

[0051] Fig.21 Schematic diagram of the exploded structure of the second implementation method including the main beam setting.

[0052] Fig. 22 A partial cross-section diagram of the second embodiment including the main beam arrangement Figure 1 .

[0053] Fig.23 A partial cross-section diagram of the second embodiment including the main beam arrangement Figure 2 .

[0054] Fig.24 Schematic diagram of the rotary shaft structure of the second embodiment including the main beam arrangement.

[0055] Fig.25 It is a schematic diagram of the locking member structure of the second embodiment provided for the main beam. DETAILED DESCRIPTION

[0056] like Figure 1 , 11 and 13, in some embodiments, a tracking drive transmission mechanism for multi-point driving of a flat single axis includes a main beam 1 and at least one rotary reducer 10, the number of which can be arranged according to the specific situation, and can be 1 or more than 1, and the internal structures of multiple rotary reducers 10 are completely the same; one of the rotary reducers 10 is connected to a motor 11, the motor 11 is controlled by a motor controller, and the motor controller and the motor 11 are connected by a cable; the rotary reducer 10 connected to the motor 11 is an active rotary reducer, and the other rotary reducers 10 are driven rotary reducers, and the torque of the active rotary reducer is transmitted to the driven rotary reducer through a transmission shaft 12, and the transmission shaft 12 rotates around the main beam 1 while rotating. Then the main beam 1 is driven to rotate.

[0057] like Figure 1-2As shown, in some embodiments, the transmission shaft 12 is provided with a plurality of connectors 13 spaced apart along the length direction, and the connectors 13 are rotatably matched with the transmission shaft 12 through self-lubricating bearings, which are prior art and will not be described in detail here, and the connectors 13 are connected to the main beam 1 through slide rails, and the connectors 13 can slide on the slide rails. Through the arrangement of the slide rails and connectors, the main beam drives the transmission shaft sliding ring to rotate; the rotation of the main beam and the rotation of the transmission shaft do not interfere with each other, and both can rotate freely within a limited range.

[0058] like Figure 11-12 As shown, in some embodiments, the connecting member 13 slides outside the slide rail 131 .

[0059] like Figure 11-12 As shown, in some embodiments, a sliding ring 15 is provided on the connecting member 13 , and the sliding ring 15 is sleeved on the outside of the slide rail 131 , and the sliding ring 15 moves along the track of the slide rail 131 .

[0060] like Figure 2 and 8 As shown, preferably, in some embodiments, the connecting member 13 slides in the slide rail 131 .

[0061] like Figure 2 and 8 As shown, preferably, in some embodiments, the connecting member 13 is provided with an annular slide 141 on the outside, and the slide rail 131 is provided with an annular groove 17 matching the annular slide, and the annular slide 141 can slide in the annular groove 17.

[0062] like Figure 8 and 12 As shown, in some embodiments, the slide rail 131 is arranged in an arc shape, and a frame 132 consistent with the shape of the main beam 1 is provided on the slide rail 131, and the main beam 1 is passed through the frame 132. Specifically, a pair of branches extending outward are provided on the frame 132, and the pair of branches can be fixed by bolts and nuts.

[0063] like Figure 4-7 As shown, in some embodiments, a transmission gear 19 is sleeved on the outside of one end of the worm 18, and a first bevel gear 100 is provided at the output end of the motor 11. Specifically, a second rotating shaft 101 is provided inside the first bevel gear 100, and the transmission shaft 12 is connected to the output end of the motor 11. A universal joint sleeve 102 is provided at the connection between the second rotating shaft 101 and the transmission shaft 12, and the second rotating shaft 101 is connected to the housing of the rotary reducer 10 through a bearing 103; the transmission gear 19 cooperates with the first bevel gear 100 through a bevel gear group 104.

[0064] like Figure 4-7As shown, in some embodiments, the bevel gear group 104 includes a second bevel gear 105 meshing with the first bevel gear 100, a transfer gear 106 arranged on one side of the first bevel gear 100, and a first rotating shaft 107 for connecting the second bevel gear 105 and the transfer gear 106. Specifically, the first rotating shaft 107 is provided with a bearing on the outer sleeve, and a fixed seat 108 is connected to the outside of the bearing, and the fixed seat 108 is fixedly connected to the inside of the outer shell of the rotary reducer 10.

[0065] like Figure 2 and 9 -10, in some embodiments, both ends of the worm wheel 109 are connected to the main beam 1 through a connecting assembly, and the connecting assembly includes a disc 110, a square shaft 111 and a connecting column 1120 arranged between the disc 110 and the square shaft 111; specifically, the disc, the square shaft and the connecting column are integrally processed, the four corners of the square shaft are arc-shaped, and the outer ring shape of the square shaft is the same as the inner wall shape of the main beam.

[0066] like Figure 9-10 As shown, in some embodiments, the square shaft 111 is eccentrically arranged relative to the disc 110. Through the eccentric arrangement, the end connected to the worm gear is designed to be smaller in size, which can avoid the installation interference of the connecting bolts, and the other end is designed to be larger in size, which can match the main beam of larger size. At the same time, the eccentric design can reduce the force arm of the bracket assembly, which means that the driving torque of the entire column of brackets is reduced, and the driving energy consumption of the entire column of brackets is effectively reduced; the disc 110 is provided with a first positioning hole 112, and the worm gear 109 is provided with a second positioning hole 113. The first positioning hole 112 is matched with the second positioning hole 113 through a locking member 114 to stop rotation. Specifically, the locking member 114 can be arranged as a bolt and a nut;

[0067] like Figure 9-10 As shown, in some embodiments, the square shaft 111 is provided with a first locking hole, and the worm gear 109 is provided with a second locking hole, and a locking member 114 is used to relatively fix the positions of the first locking hole and the second locking hole. Specifically, the locking member 114 can be arranged in the form of a bolt and a nut.

[0068] like Figure 7 As shown, in some embodiments, the housing of the rotary reducer 10 is provided with a first limit portion 116, and the worm wheel 109 is provided with a second limit portion 117 in the circumferential direction to cooperate with the first limit portion 116. The first limit portion 116 and the second limit portion 117 are provided to ensure that the rotary reducer 10 has a higher stability during rotation, and secondly, to ensure that there is still a higher safety protection capability when the external travel switch fails.

[0069] like Figure 7As shown, in some embodiments, the first limiting portion 116 is provided with at least two convex corners, which are fixedly connected to the top of the housing of the rotary reducer 10, and the second limiting portion 117 is provided with a convex ring, which is fixedly connected to the circumference of the worm gear 109.

[0070] like Fig.13 As shown, in some embodiments, the main beam 1 is arranged inside the rotary reducer 10. By arranging it inside, the joints between the main beams 1 can be effectively reduced, the rigidity and strength of the entire column bracket can be increased, and the risk can be reduced.

[0071] like Figure 2 and 22 As shown, in some embodiments, the main beam 1 is provided with a rotating shaft 2 on the outside, and the rotating shaft 2 is matched with the worm gear 109 through a rolling bearing 20. Specifically, the rolling bearing 20 is a four-point contact ball bearing. The four-point contact ball bearing is a prior art, and it is a separable bearing, or it can be said that it is an angular contact ball bearing that can withstand bidirectional axial loads, which will not be described here.

[0072] like Figure 14-15 As shown in Figures 21-23, in some embodiments, the main beam 1 is connected to the rotating shaft 2 and the housing of the rotary reducer 10 through a locking member 21.

[0073] like Fig.15 and 18 -As shown in FIG. 19, in some embodiments, the locking member 21 is provided with a convex ring 210 extending outward in the axial direction. Specifically, the inner wall of the convex ring 210 matches the outer wall of the main beam 1, and the outer wall of the convex ring 210 is arranged in a circular arc shape. In this embodiment, the number of the locking members 21 is 4, which are evenly distributed in the circumferential direction of the main beam 1; the outer wall of the convex ring 210 is a first inclined surface 211a structure arranged from top to bottom, and the inner walls of the rotating shaft 2 and the rotating reducer 1 housing are both second inclined surface 212 structures arranged from bottom to top, and the first inclined surface 211a can move left and right along the second inclined surface 212.

[0074] like Fig.15 and 18-19, in some embodiments, the locking member 21 is provided with a truncated cone 22 extending outward in the radial direction, and a first locking hole 23 is opened on the truncated cone 22. The rotary shaft 2 and the housing of the rotary reducer 10 are both provided with a second locking hole 24. The first locking hole 23 is locked with the second locking hole 24 through a locking member 25, and the locking member 25 can be provided with a bolt and a nut. When the locking member 21 is axially locked by the locking member 25 and moves, the radial spacing between the four locking members 21 will shrink and change, and the locking force of the screw will be changed to the radial pressure of the locking member 21 on the main beam 1 through the change of the first inclined surface 26 and the second inclined surface 27, thereby achieving the function of locking the torque tube of the main beam 1.

[0075] like Figure 20-25 As shown, preferably, in some embodiments, the outer wall of the locking member 21 is a first inclined surface 211a structure arranged from top to bottom, and the locking member 21 is arranged in 4 pairs, which are evenly distributed on the left and right sides of the circumference of the main beam 1. Specifically, the inner wall of the locking member 21 is a plane setting, and the side in contact with the main beam 1 is a plane; a plurality of inwardly extending reinforcing ribs 220 are arranged on the circumference of the inner wall of the rotating shaft 2, and the number of the reinforcing ribs is set to 8-12. The inner wall of the reinforcing rib 220 is a second inclined surface 212a structure arranged from bottom to top, and the first inclined surface 211a can move left and right along the second inclined surface 212a.

[0076] like Figure 20-25 As shown, preferably, in some embodiments, the locking piece 21 is provided with a boss 221 extending outward in the radial direction, and a first locking hole 23a is provided on the boss 211. The rotary shaft 2 and the outer shell of the rotary reducer 10 are provided with a second locking hole 24a, and the first locking hole 23a is anti-rotationally matched with the second locking hole 24a through a locking piece 25a; when the main beam passes through the inner hole, the locking piece 25a is twisted to pull the locking piece 21 to produce axial movement, and the locking piece 21 changes its radial position through sliding engagement with the second inclined surface of the reinforcement rib. When the locking piece 21 moves to a suitable position, the spacing between the two symmetrical groups of locking pieces 21 becomes smaller, and the plane of each locking piece 21 is in contact with the outer plane of the torque tube main beam, thereby achieving the purpose of locking the main beam torque tube.

[0077] like Fig.18 and 25 As shown, in some embodiments, the inner wall shape of the locking member 21 is set to be the same as the outer wall shape of the main beam 1.

[0078] like Figure 16-17As shown, in some embodiments, the slewing reducer 10 and the transmission shaft 12 are arranged to rotate synchronously with the main beam 1 in the same direction. During the rotation of the main beam 1 and the slewing reducer 10, the transmission shaft 12 also rotates synchronously with the main beam 1 in the same direction, ensuring that the main beam 1 will not touch the transmission shaft 12 during rotation, causing the main beam 1 to get stuck and unable to rotate. Secondly, during the rotation of the main beam 1 and the transmission shaft 12, the connected lines will also be driven to rotate together. Therefore, the lines do not need to be set very long, and the lines can be simplified. During the rotation, the lines will not get knotted or tangled. Finally, due to the synchronous and same-direction rotation of the transmission shaft 12 and the main beam 1, the bearing capacity of the transmission shaft 12 is improved, thereby extending the service life of the transmission shaft 12.

[0079] like Figure 16-17 As shown, in some embodiments, the rotary reducer 10 is a worm gear 109 rotary reducer 10, the worm gear 109 of the rotary reducer 10 is fixedly arranged on the column, the outer shell of the rotary reducer 10 is fixedly connected to the main beam 1, and the worm gear 109 and the outer shell are rotationally matched; when the motor 11 is started, the worm 18 rotates while revolving around the worm gear 109, driving the rotary reducer 10 and the main beam 1 to rotate, the worm gear 109 of the rotary reducer 10 is fixedly arranged on the column, the outer shell of the rotary reducer 10 is fixedly connected to the main beam 1, and the worm gear 109 and the outer shell are rotationally matched; when the motor 11 is started, the worm 18 rotates while revolving around the worm gear 109, driving the rotary reducer 10 and the main beam 1 to rotate.

[0080] like Figure 16-17 As shown, in some embodiments, a third bevel gear 200 and an output gear 201 are sleeved on one end of the worm 18, a first gear 202 is provided on the input end of the motor 11, and a second bevel gear 204 is sleeved on the transmission shaft 12. When the motor 11 is started, the motor 11 drives the first gear 202 to rotate, the first gear 202 meshes with the third bevel gear 200, the third bevel gear 200 rotates and meshes with the second bevel gear 204, and the second bevel gear 204 rotates to drive the transmission shaft 12 to rotate.

[0081] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0082] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A solar tracker, comprising a main beam and at least one slewing reducer, wherein one slewing reducer is connected to a motor, the motor is controlled by a motor controller, and the motor controller and the motor are connected by a cable; characterized in that: The slewing reducer connected to the motor is the active slewing reducer, and the other slewing reducers are driven slewing reducers. The torque of the active slewing reducer is transmitted to the driven slewing reducer through the transmission shaft. The active slewing reducer and the driven slewing reducer rotate synchronously, thereby driving the main beam to rotate; the main beam is arranged inside the slewing reducer; The main beam is connected to the rotary shaft and the housing through a locking member; The locking member is provided with a convex ring extending outward in the axial direction, the outer wall of the convex ring is provided with a first inclined surface structure from top to bottom, the inner walls of the rotary shaft and the rotary reduction housing are both provided with a second inclined surface structure from bottom to top, and the first inclined surface can move left and right along the second inclined surface; The locking member is provided with a frustum of cone extending outward in the radial direction, a first locking hole is formed on the frustum of cone, a second locking hole is formed on the housing of the rotary shaft and the rotary reducer, and the first locking hole is engaged with the second locking hole through the locking member to prevent rotation.

2. A solar tracker according to claim 1, characterized in that: A rotary shaft is sleeved on the outside of the main beam, and the rotary shaft cooperates with the worm gear through a rolling bearing.

3. A solar tracker according to claim 1, characterized in that: The outer wall of the locking member is provided with a first inclined surface structure from top to bottom, and the inner wall of the rotating shaft is circumferentially provided with a plurality of reinforcing ribs extending inwardly, and the inner wall of the reinforcing rib is provided with a second inclined surface structure from bottom to top, and the first inclined surface can move left and right along the second inclined surface.

4. A solar tracker according to claim 3, characterized in that The locking member is provided with a boss extending outward in the radial direction, and a first locking hole is provided on the boss. The rotary shaft and the outer shell of the rotary reducer are both provided with a second locking hole, and the first locking hole is anti-rotationally matched with the second locking hole through the locking member.

5. A solar tracker according to claim 1, characterized in that: The inner wall shape of the locking member is arranged to be identical to the outer wall shape of the main beam.

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