Circulating fan with fork arm supporting structure

Abstract

The circulating fan with the fork arm supporting structure comprises a fan body and a base, the fan body is arranged in a fork arm, the fan body is provided with a motor shell and a fan blade motor, the fan body is provided with an up-down swing driving mechanism, and the up-down swing driving mechanism comprises a first motor, a first crank, a first connecting rod, a swing arm and a force transmission arm; one end of the first crank is installed on an output rotating shaft of the first motor, the other corresponding end of the first crank is hinged to one end of the first connecting rod, the other corresponding end of the first connecting rod is hinged to one end of the swing arm, the other corresponding end of the swing arm is in positioning connection with one end of the force transmission arm, and the other corresponding end of the force transmission arm is in positioning connection with the fork arm. The first motor is installed in the rear portion of the motor shell, and the first crank, the first connecting rod and the swing arm are arranged in the motor shell. According to the circulating fan, the reliability of the up-down swing driving mechanism is better, and the visual effect of the circulating fan is improved.

Description

Technical Field

[0001] The invention relates to the field of circulating fans, and in particular to a circulating fan with a fork arm supporting structure. Background Art

[0002] At present, the circulation fan is provided with turbine blades, which can output a relatively concentrated airflow with a longer range when rotating. The Chinese invention patent with publication number CN219045469U discloses "a circulation fan": the second eccentric shaft motor drives the second driving gear to rotate, the second driving gear drives the second driven gear to rotate, and the second driven block rotates accordingly, driving the wind cover body to rotate, thereby realizing the up and down swinging of the circulation fan. Since the second eccentric shaft motor, the second driving gear and the second driven gear are all arranged in the upper end of the supporting arc plate, although the up and down swinging driving component is hidden, which is beneficial to the appearance, on the one hand, the volume of the above-mentioned parts can only be reduced by a small amount, which leads to the problem of insufficient driving force and easy damage of parts. On the other hand, in daily use, the upper end of the supporting arc plate is easily impacted, so the up and down swinging driving component is easily displaced or damaged due to the impact, that is, the reliability is not good, so it is necessary to improve the above-mentioned circulation fan. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a circulating fan with a fork arm support structure, the reliability of its up and down swinging drive mechanism is better, and it is also beneficial to improve the visual effect of the circulating fan.

[0004] The purpose of the present invention is achieved through the following technical solutions.

[0005] The circulating fan disclosed in the present invention comprises a fan body and a base, wherein the base is provided with a fork arm, the fan body is hinged to the fork arm, and the fan body is arranged in the fork arm, wherein the fan body is provided with a motor housing and a fan blade motor, and the fan blade motor is arranged in the front part of the motor housing, and the fan body is provided with an up and down swing driving mechanism, and the up and down swing driving mechanism comprises a first motor, a first crank, a first connecting rod, a swing arm and a force transmission arm, one end of the first crank is installed on the output shaft of the first motor, the other end corresponding to the first crank is hinged to one end of the first connecting rod, the other end corresponding to the first connecting rod is hinged to one end of the swing arm, the other end corresponding to the swing arm is positioned and connected with one end of the force transmission arm, and the other end corresponding to the force transmission arm is positioned and connected with the fork arm, and the swing arm can swing relative to the first connecting rod around the hinge axis of the fan body and the fork arm, and the first motor is installed in the rear part of the motor housing, and the first crank, the first connecting rod and the swing arm are arranged in the motor housing.

[0006] Preferably, the fan body includes an air inlet cover and a front shell, the front end of the air inlet cover is installed and connected to the rear end of the front shell, the outside of the motor shell is provided with spokes and a support ring, one end of the spoke is connected to the support ring, and the other corresponding end of the spoke is connected to the outer wall of the motor shell, the support ring is adapted to be arranged in the rear end part of the front shell, the spokes are circumferentially distributed around the axis of the front shell, and the force transmission arm is arranged between the corresponding two spokes.

[0007] Preferably, the base includes a fixed chassis and a movable disk assembly, the fixed chassis is formed with a convex tube, the movable disk assembly includes a movable chassis, a disk cover and a decorative cover plate, the disk cover is adapted to be arranged in the upper end of the movable chassis, the disk cover is installed and connected to the movable chassis by screws, the decorative cover plate is abutted against the disk cover, the movable chassis is arranged on the upper side of the fixed chassis, the fan body is arranged directly above the decorative cover plate, the fork arm is installed and connected to the movable chassis, a rotating connecting hole is formed in the middle part of the movable chassis, the convex tube passes through the rotating connecting hole, a blocking cover is installed on the upper end of the convex tube, the blocking cover is abutted against the upper side of the edge of the rotating connecting hole, and the disk cover is arranged above the blocking cover.

[0008] Preferably, the base is provided with a left-right swing driving mechanism, and the left-right swing driving mechanism includes a second motor, a second crank, a second connecting rod and a wobble plate. The second motor drives the second crank to rotate, and the second crank is connected to the wobble plate through the second connecting rod. The wobble plate is installed on the fixed chassis, and the upper part of the wobble plate is adapted to be arranged between the outer wall of the convex tube and the inner wall of the rotating connecting hole. The second motor is installed on the upper side of the movable chassis, and the second crank and the second connecting rod are arranged in a cavity surrounded by the fixed chassis and the movable chassis.

[0009] Preferably, the decorative cover plate is arranged in the fork arm.

[0010] Compared with the prior art, the present invention has the following beneficial effects: an up and down swinging driving mechanism is provided, including a first motor, a first crank, a first connecting rod, a swing arm and a force transmission arm; one end of the first crank is mounted on the output shaft of the first motor; the other end corresponding to the first crank is hinged to one end of the first connecting rod; the other end corresponding to the first connecting rod is hinged to one end of the swing arm; the other end corresponding to the swing arm is positioned connected to one end of the force transmission arm; the other end corresponding to the force transmission arm is positioned connected to the fork arm; the swing arm can swing relative to the first connecting rod around the hinge axis of the fan body and the fork arm; the first motor is mounted in the rear part of the motor housing; the first crank, the first connecting rod and the swing arm are arranged in the motor housing; this is beneficial to improving the reliability of the up and down swinging driving mechanism and is also beneficial to improving the visual effect of the circulation fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the three-dimensional structure of the back side of the circulation fan of the present invention.

[0012] Figure 2 The figure is a schematic diagram of the back three-dimensional structure of the circulation fan with the air inlet cover removed according to the present invention.

[0013] Figure 3 The present invention is a schematic diagram of the back three-dimensional structure of the circulation fan with the air inlet cover and the motor housing removed.

[0014] Figure 4 It is a schematic cross-sectional structural diagram of the circulation fan of the present invention.

[0015] Figure 5 It is a three-dimensional structural schematic diagram of the fork arm, base and up and down swing driving mechanism combination of the present invention.

[0016] Figure 6 It is a schematic diagram of the three-dimensional structure of the combination of the fork arm and the base (with the decorative cover removed) of the present invention when viewed from top.

[0017] Figure 7 It is a schematic diagram of the three-dimensional structure of the combination of the fork arm and the base (with the decorative cover plate and the plate cover removed) of the present invention when viewed from top.

[0018] Figure 8 It is a schematic diagram of the three-dimensional structure of the combination of the fixed chassis and the left and right swing driving mechanism of the present invention.

[0019] Fig. 9 It is a three-dimensional structural schematic diagram of the movable chassis of the present invention.

[0020] Explanation of reference numerals: fan body 1; motor housing 11; spokes 111; support ring 112; air inlet housing cover 12; front housing 13; turbine blades 14; up and down swinging driving mechanism 15; first motor 151; first crank 152; first connecting rod 153; swing arm 154; connecting seat 155; force transmission arm 156; connecting piece 157; positioning protrusion 1571; blade motor 17; base 2; fixed chassis 21; protruding pipe 211; movable disk assembly 22; movable chassis 221; rotating connecting hole 2211; disk cover 222; countersunk hole 2221; decorative cover plate 223; left and right swinging driving mechanism 23; second motor 231; second crank 232; second connecting rod 233; swing plate 234; blocking cover 24; fork arm 3. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] The circulating fan with fork arm support structure of the present invention is as follows: Figures 1 to 3As shown, the fan body 1 includes a fan body 1 and a base 2. A fork arm 3 is provided on the base 2. The fan body 1 is hinged to the fork arm 3. The hinge axis of the fan body 1 and the fork arm 3 is located in a horizontal plane, so that the fan body 1 can swing up and down. The fan body 1 is arranged in the fork arm 3. Figure 1 As shown, the fork arm 3 includes two vertical plate parts, and the fan body 1 is located between the two vertical plate parts. Figures 2 to 4 As shown, the fan body 1 is provided with a motor housing 11 and a fan motor 17. The fan motor 17 is arranged in the front part of the motor housing 11. The output shaft of the fan motor 17 extends forward from the motor housing 11. The turbine blades 14 are mounted on the output shaft of the fan motor 17. The fan body 1 is provided with an up and down swing driving mechanism 15. Figure 3 and Figure 5 As shown, the up-and-down swing driving mechanism 15 includes a first motor 151, a first crank 152, a first connecting rod 153, a swing arm 154 and a force transmission arm 156. One end of the first crank 152 is mounted on the output shaft of the first motor 151. The first crank 152 and the output shaft of the first motor 151 can be relatively fixed by a set screw. The other end of the first crank 152 corresponding to the first connecting rod 153 is hinged to one end of the first connecting rod 153. The other end of the first connecting rod 153 corresponding to the first connecting rod 153 is hinged to one end of the swing arm 154. The swing arm 154 corresponding to the first connecting rod 153 is hinged to one end of the swing arm 154. The other end of the force transmission arm 156 is positioned and connected to one end of the force transmission arm 156. Specifically, the up and down swing driving mechanism 15 also includes a connecting seat 155, and the connecting seat 155 is connected to the swing arm 154 through a key structure, so that the connecting seat 155 and the swing arm 154 are relatively positioned in the circumferential direction (about the swing axis of the swing arm 154), that is, the swing arm 154 cannot swing relative to the connecting seat 155. One end of the force transmission arm 156 is installed on the connecting seat 155 through a corresponding screw, and the other end of the force transmission arm 156 is positioned and connected to the fork arm 3. Specifically, as Figure 5 As shown, the up-and-down swing driving mechanism 15 also includes a connecting member 157, a positioning protrusion 1571 is formed on one side of the connecting member 157, an inner convex shaft head is integrally formed on the inner side of the fork arm 3, the inner convex shaft head is adapted to be inserted into the connecting member 157 and the force transmission arm 156, the positioning protrusion 1571 is adapted to be inserted into the square through hole of the force transmission arm 156, and a hinge hole is formed at the rear end of the front shell 13, and the hinge hole is adapted to be fitted outside the connecting member 157. In other words, the fan body 1 and the fork arm 3 are hinged to the above The inner convex shaft head of the connecting member 157 is provided with a block on the other side thereof, and the block is engaged with the corresponding vertical plate portion. The block and the positioning protrusion 1571 are both located radially outside the inner convex shaft head, so that the connecting member 157 cannot rotate around the inner convex shaft head, and the force transmission arm 156 cannot rotate around the inner convex shaft head. Through the above arrangement, the fork arm 3, the force transmission arm 156, the connecting member 157, the connecting seat 155 and the swing arm 154 cannot rotate relative to each other. Figure 5As shown, the swing arm 154 can swing relative to the first connecting rod 153 around the hinge axis of the fan body 1 and the fork arm 3, that is, the swing arm 154 can swing relative to the first connecting rod 153 around the above-mentioned inner convex shaft head, that is, the hinge axis of the swing arm 154 and the first connecting rod 153 and the axis of the above-mentioned inner convex shaft head coincide. Figures 1 to 3 As shown, the first motor 151 is installed in the rear part of the motor housing 11, specifically, the housing of the first motor 151 is installed on the rear inner wall of the motor housing 11 through corresponding screws, the first crank 152, the first connecting rod 153 and the swing arm 154 are arranged in the motor housing 11, and the convex sleeve structure at one end of the connecting seat 155 extends into the motor housing 11 and is connected to the swing arm 154, and the force transmission arm 156 is located between the corresponding vertical plate part and the motor housing 11 (in the axial direction of the inner convex shaft head). In other words, the fork arm 3 transmits the supporting force to the swing arm 154 through the force transmission arm 156.

[0023] By setting the above structure, such as Figure 1 and Figure 2 As shown, the first crank 152, the first connecting rod 153 and the swing arm 154 are hidden in the motor housing 11, and the user can only easily see the force transmission arm 156 through the air inlet cover 12, thereby preventing the user from seeing the messy transmission structure in the fan body 1, and preventing the first crank 152, the first connecting rod 153 and the swing arm 154 from being outside the motor housing 11, which may cause dust or small debris to accumulate easily, thereby helping to improve the visual effect of the circulation fan; it also prevents the lubricating grease of the up and down swinging drive mechanism 15 from being exposed to the outside, thereby preventing the up and down swinging drive mechanism 15 from being easily stained with dust and debris and affecting the work, and when the user disassembles the air inlet cover 12 to clean the inside of the fan body 1, the above-mentioned lubricating grease must not be removed by mistake, thereby preventing the up and down swinging drive mechanism 15 from malfunctioning.

[0024] like Figure 2 As shown, since the first motor 151, the first crank 152, the first connecting rod 153 and the swing arm 154 are built into the motor housing 11, the above-mentioned parts are prevented from being easily impacted, and the internal space of the motor housing 11 can be relatively large (relative to the vertical plate portion of the fork arm 3), so it is avoided that the volume of the parts of the up and down swinging drive mechanism 15 needs to be reduced, which is beneficial to make the parts of the up and down swinging drive mechanism 15 have better strength, and the first motor 151 can be selected with a larger power model, so that the reliability of the up and down swinging drive mechanism of the present invention is better.

[0025] like Figure 3As shown, the first motor 151 drives the first crank 152 to rotate, the first crank 152 drives the first connecting rod 153 to swing back and forth, and the first connecting rod 153 drives the swing arm 154 to swing back and forth, so that the swing arm 154 and the fork arm 3 swing back and forth synchronously. However, in actual applications, the base 2 is placed on a table, and the up and down swinging of the fork arm 3 is hindered by the table. In fact, the fan body 1 is swingably arranged on the fork arm 3, so in fact, the first motor 151 drives the fan body 1 to swing up and down, thereby realizing the up and down swinging air supply.

[0026] Furthermore, if Figure 1 As shown, the fan body 1 includes an air inlet cover 12 and a front shell 13. The front shell 13 is roughly cylindrical in shape. The front end of the air inlet cover 12 is installed and connected to the rear end of the front shell 13. Specifically, the front end of the air inlet cover 12 is connected to the rear end of the front shell 13 through a rotating buckle structure. Figure 2 As shown, the outside of the motor housing 11 is provided with a spoke 111 and a support ring 112, one end of the spoke 111 is connected to the support ring 112, and the other end of the spoke 111 is connected to the outer wall of the motor housing 11, the support ring 112 is adapted to be arranged in the rear end portion of the front housing 13, and the rear end portion of the front housing 13 is formed with an inner convex mounting block, and the support ring 112 is installed and connected to the above-mentioned inner convex mounting block by corresponding screws. In other words, the motor housing 11 and the turbine blades 14 are located in the space surrounded by the front housing 13 and the air inlet cover 12, the spokes 111 are circumferentially distributed around the axis of the front housing 13, or it can be said that the spokes 111 are distributed around the motor housing 11, and the number of the spokes 111 can be set to six, so as to firmly connect the motor housing 11 and the front housing 13, and the force transmission arm 156 (in the circumferential direction of the front housing 13) is arranged between the corresponding two spokes 111.

[0027] Furthermore, if Figures 4 to 9 As shown, the base 2 includes a fixed chassis 21 and a movable disk assembly 22. The fixed chassis 21 is formed with a convex tube 211. The movable disk assembly 22 includes a movable chassis 221, a disk cover 222 and a decorative cover plate 223. The disk cover 222 is adapted to be arranged in the upper end of the movable chassis 221. The disk cover 222 is installed and connected to the movable chassis 221 by screws. Specifically, as shown in FIG. Figure 6 As shown, a countersunk hole 2221 is formed on the plate cover 222, and a screw is used to install it in the corresponding countersunk hole 2221 and screw it to the movable chassis 221, as shown in FIG. Figure 5 and Figure 6 As shown, the decorative cover plate 223 is arranged on the plate cover 222, and the decorative cover plate 223 can be bonded to the plate cover 222. Figure 4 As shown, the movable chassis 221 is arranged on the upper side of the fixed chassis 21, as shown in FIG. Figure 1As shown, the fan body 1 is arranged above the decorative cover plate 223, that is, the fan body 1 is suspended, so when the fan body 1 blows air obliquely upward, the movable disk assembly 22 will not significantly affect the air intake effect of the air intake cover 12. Figure 7 As shown, the fork arm 3 is installed and connected with the movable chassis 221, as shown in FIG. Fig. 9 As shown, a rotation connection hole 2211 is formed in the middle of the movable chassis 221. Figure 4 and Figure 7 As shown, the protruding tube 211 passes through the rotating connection hole 2211, so that the movable chassis 221 can rotate horizontally relative to the fixed chassis 21, and the upper end of the protruding tube 211 is installed with a blocking cover 24 through corresponding screws. The blocking cover 24 is close to the upper side of the edge of the rotating connection hole 2211, and the disk cover 222 is arranged above the blocking cover 24. The center of the blocking cover 24 is formed with a threading hole, and the power line can pass through the threading hole and the protruding tube 211 to reach the bottom of the fixed chassis 21; through the above arrangement, when the fixed chassis When the base 21 moves downward relative to the movable base 221, the blocking cover 24 will be blocked by the edge of the rotating connection hole 2211, preventing the fixed base 21 from being separated from the movable base 221. By hiding the blocking cover 24 between the plate cover 222 and the movable base 221, it is prevented that the user can easily remove the blocking cover 24 to separate the fixed base 21 from the movable base 221. Since users generally do not have professional maintenance skills, it is prevented that users privately disassemble the base 2, which may cause poor circulation fan function or even cause safety accidents. Figure 4 As shown, when professional maintenance personnel need to disassemble the base 2, Figure 6 As shown, the decorative cover plate 223 can be removed first to expose the countersunk hole 2221, and then the screws installed in the countersunk hole 2221 can be removed, and then the plate cover 222 can be removed. Figure 7 As shown, the screws for installing the blocking cover 24 can be further removed.

[0028] Furthermore, if Figure 2 , Figure 7 and Figure 8 As shown, the base 2 is provided with a left-right swing driving mechanism 23, which includes a second motor 231, a second crank 232, a second connecting rod 233 and a swing plate 234. The second motor 231 drives the second crank 232 to rotate, and the second crank 232 is connected to the swing plate 234 through the second connecting rod 233. The swing plate 234 is installed on the fixed chassis 21, and the upper part of the swing plate 234 is adapted to be arranged between the outer wall of the convex tube 211 and the inner wall of the rotating connecting hole 2211. In other words, the upper part of the swing plate 234 is a tubular structure, as shown in FIG. Figure 7 As shown, the second motor 231 is installed on the upper side of the movable chassis 221. Figure 8 Combination Figure 7As shown, the second crank 232 and the second connecting rod 233 are arranged in the cavity surrounded by the fixed chassis 21 and the movable chassis 221, and the hinge point of the second connecting rod 233 and the swing plate 234 is located outside the rotation axis of the movable chassis 221 and the fixed chassis 21 (that is, the axis of the convex tube 211). Since the working principle of the left and right swinging drive mechanism 23 is roughly the same as the working principle of the up and down swinging drive mechanism 15, and the left and right reciprocating swinging air supply function of the circulating fan belongs to the prior art, the working principle of the left and right swinging drive mechanism 23 is no longer described in detail. The present invention arranges the second motor 231 on the upper side of the movable chassis 221, and arranges the second crank 232 and the second connecting rod 233 on the lower side of the movable chassis 221. The output shaft of the second motor 231 passes through the movable chassis 221, so that the position of the second motor 231 can be raised, and the user is prevented from accidentally knocking over a cup on the desktop and making the second motor 231 easily wet. The power line that passes downward through the convex tube 211 and leads out of the fixed chassis 21 has a relatively good waterproof effect because it is wrapped with an insulating outer skin. A circuit board is installed on the upper side of the movable chassis 221.

[0029] Furthermore, if Figure 3 As shown, the decorative cover plate 223 is arranged in the fork arm 3, that is, the decorative cover plate 223 is arranged between the two vertical plate parts of the fork arm 3. Specifically, as shown in FIG. Figure 7 As shown, the movable plate assembly 22 is circular, and a bent plate is formed at the lower end of the vertical plate portion, and the bent plate is bent toward the center of the movable chassis 221. Specifically, the bent plate is installed and connected to the movable chassis 221, so that the main body of the vertical plate portion can be placed outside the movable chassis 221. Figure 1 , Figure 5 and Figure 6 As shown, the vertical plate portion can be prevented from interfering with the disk cover 222 and the decorative cover plate 223 , and the fork arm 3 can be prevented from interfering with the cleaning of the decorative cover plate 223 .

Claims

1. A circulation fan with a fork arm support structure, comprising a fan body (1) and a base (2), wherein the base (2) is provided with a fork arm (3), the fan body (1) is hingedly connected to the fork arm (3), and the fan body (1) is arranged in the fork arm (3), characterized in that: The fan body (1) is provided with a motor housing (11) and a fan blade motor (17), wherein the fan blade motor (17) is arranged in the front part of the motor housing (11), and the fan body (1) is provided with an up-and-down swing driving mechanism (15), wherein the up-and-down swing driving mechanism (15) comprises a first motor (151), a first crank (152), a first connecting rod (153), a swing arm (154) and a force transmission arm (156), wherein one end of the first crank (152) is mounted on an output shaft of the first motor (151), and the other end of the first crank (152) corresponding to the first motor (151) is hinged to one end of the first connecting rod (153), and the first The other end corresponding to the connecting rod (153) is hinged to one end of a swing arm (154), and the other end corresponding to the swing arm (154) is positionally connected to one end of the force transmission arm (156), and the other end corresponding to the force transmission arm (156) is positionally connected to the fork arm (3). The swing arm (154) can swing relative to the first connecting rod (153) around a hinge axis between the fan body (1) and the fork arm (3). The first motor (151) is installed in the rear part of the motor housing (11), and the first crank (152), the first connecting rod (153) and the swing arm (154) are arranged in the motor housing (11).

2. The circulating fan with a fork arm support structure according to claim 1, characterized in that: The fan body (1) comprises an air inlet cover (12) and a front shell (13); the front end of the air inlet cover (12) is mounted and connected to the rear end of the front shell (13); a spoke (111) and a support ring (112) are provided on the outside of the motor shell (11); one end of the spoke (111) is connected to the support ring (112) as a whole; the other end of the spoke (111) is connected to the outer wall of the motor shell (11); the support ring (112) is adapted to be arranged in the rear end of the front shell (13); the spokes (111) are circumferentially distributed around the axis of the front shell (13); and the force transmission arm (156) is arranged between two corresponding spokes (111).

3. The circulating fan with a fork arm support structure according to claim 1, characterized in that: The base (2) comprises a fixed chassis (21) and a movable disk assembly (22), wherein a convex tube (211) is formed on the fixed chassis (21), and the movable disk assembly (22) comprises a movable chassis (221), a disk cover (222) and a decorative cover plate (223), wherein the disk cover (222) is adapted to be arranged in the upper end of the movable chassis (221), the disk cover (222) is mounted and connected to the movable chassis (221) by screws, and the decorative cover plate (223) is arranged to be close to and cover the disk cover (222), and the movable chassis (221) is arranged on the fixed chassis (21). The fan body (1) is arranged on the upper side of the fixed chassis (21), and is directly above the decorative cover plate (223). The fork arm (3) is installed and connected to the movable chassis (221). A rotating connection hole (2211) is formed in the middle of the movable chassis (221). The convex tube (211) passes through the rotating connection hole (2211). A blocking cover (24) is installed on the upper end of the convex tube (211). The blocking cover (24) is attached to the upper side of the edge of the rotating connection hole (2211). The disk cover (222) is arranged above the blocking cover (24).

4. The circulation fan with a fork arm support structure according to claim 3, characterized in that: The base (2) is provided with a left-right swing driving mechanism (23), the left-right swing driving mechanism (23) comprising a second motor (231), a second crank (232), a second connecting rod (233) and a swing plate (234), the second motor (231) driving the second crank (232) to rotate, the second crank (232) being connected to the swing plate (234) via the second connecting rod (233), the swing plate (234) being mounted on the fixed chassis (21), the upper part of the swing plate (234) being adapted to be arranged between the outer wall of the convex tube (211) and the inner wall of the rotating connecting hole (2211), the second motor (231) being mounted on the upper side of the movable chassis (221), the second crank (232) and the second connecting rod (233) being arranged in a cavity enclosed by the fixed chassis (21) and the movable chassis (221).

5. The circulation fan with a fork arm support structure according to claim 4, characterized in that: The decorative cover plate (223) is arranged inside the fork arm (3).

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