Protective cover opening and closing device

Abstract

The invention belongs to the field of window sashes, door leaves or similar components for closing openings, and particularly relates to a protective cover opening and closing device. In order to simplify the structure and reduce the cost, the protective cover opening and closing device comprises a rack and a protective cover, a locking block is arranged on the rack, a spring bolt and a fifth connecting rod are hinged to the inner side of the protective cover, and a sixth connecting rod is hinged between the spring bolt and the fifth connecting rod to form a four-connecting-rod mechanism; a second connecting rod is further hinged to the protective cover, a direct-acting driving mechanism used for controlling one end of the second connecting rod to rotate forwards and backwards is arranged on the rack, when the second connecting rod rotates forwards, the fifth connecting rod is driven by the transmission connecting rod to rotate forwards so that the spring bolt can move to the locking state, and when the second connecting rod rotates backwards, the spring bolt is far away from the locking block. The protective cover is further provided with a stopping part used for being matched with the second connecting rod in a stopping mode when the second connecting rod rotates reversely to the limiting position so that the protective cover can be pushed to be opened upwards under continuous driving of the direct-acting driving mechanism. The protective cover is locked, unlocked, opened and closed through a direct-acting driving mechanism, the structure is simple, and the cost is low.

Description

Technical Field

[0001] The invention belongs to the field of window sashes, door sashes or similar components used for closing openings, and in particular relates to a protective cover opening and closing device. Background Art

[0002] In the prior art, it is often necessary to open a window on the device and set a protective cover at the window. When it is necessary to complete relevant operations through the window, the protective cover needs to be opened to perform the operations; after the operations are completed, the protective cover needs to be closed to prevent dust, rainwater and other debris from entering the device.

[0003] For example, the Chinese utility model patent with the authorization announcement number CN216486858U and the authorization announcement date 2022.05.10 discloses a comprehensive training device based on the Internet of Things, which includes a training table, a protective cover hinged at one end to the training table, and a cylinder for opening the protective cover. When the Internet of Things training is required, the piston rod of the cylinder moves upward, and the protective cover is opened under the drive of the cylinder; when the protective cover is opened to the appropriate position, the piston rod of the cylinder stops moving, thereby stopping the movement of the protective cover, and then the staff can operate the training equipment; after the operation is completed, the piston rod of the cylinder moves downward, thereby closing the protective cover.

[0004] When the size of the protective cover is large, when the protective cover is subjected to external vibration disturbance, the end of the protective cover away from its own rotation axis is easy to warp up, thereby causing dust or rainwater to enter the protective cover and affecting the sealing of the protective cover.

[0005] In order to improve the sealing performance of the protective cover, a locking structure that locks with the equipment frame can be provided at the end of the protective cover away from its own rotation axis. Referring to the Chinese utility model patent with authorization announcement number CN209523232U and authorization announcement date 2019.10.22, the locking structure may include a motor installed at the bottom of the protective cover, a pin connected to the output end of the motor and capable of moving horizontally, and a socket located on the frame. After closing the protective cover, the motor drives the pin to be inserted into the socket, thereby preventing the end of the protective cover away from its own rotation axis from warping up, thereby improving the sealing performance of the protective cover.

[0006] However, in the technical solution after combining the above two patents, each time the protective cover is opened, it is necessary to first control the motor to drive the pin to withdraw from the socket, and then control the piston rod of the cylinder to move upward, that is, the operator needs to issue two operating instructions in succession (the pin withdraws from the socket instruction and the piston rod rises instruction). Similarly, when closing the protective cover, the operator also needs to issue two operating instructions in succession (the piston rod descends instruction and the pin inserts into the socket instruction), which makes the operation very inconvenient and requires the setting of two sets of power mechanisms, which is costly. Summary of the invention

[0007] The purpose of the present invention is to provide a protective cover opening and closing device to solve the technical problem that the operator needs to issue two operating instructions in succession each time the protective cover is opened or closed, which is inconvenient to operate and requires the setting of two sets of power mechanisms, resulting in high costs.

[0008] In order to achieve the above-mentioned purpose, the technical solution of the protective cover opening and closing device provided by the present invention is: A protective cover opening and closing device comprises a frame and a protective cover hinged on the frame at one end, a locking block is provided on the frame at a side away from the hinged position of the protective cover, a locking tongue and a fifth connecting rod are hinged on the inner side of the protective cover, a sixth connecting rod is hinged between the locking tongue and the fifth connecting rod to form a four-link mechanism, the locking tongue has a function of cooperating with the locking block in the opening direction of the protective cover when the fifth and sixth connecting rods are rotated to a certain angle to keep the protective cover in a closed locking state; the protective cover is also hinged on a second connecting rod, a direct-acting drive mechanism for controlling the forward and reverse rotation of one end of the second connecting rod is provided on the frame, the other end of the second connecting rod is hinged with the fifth connecting rod through a transmission connecting rod, when the second connecting rod rotates forward, the fifth connecting rod is driven to rotate forward through the transmission connecting rod to move the locking tongue to a locked state, and when the second connecting rod reverses, the locking tongue is away from the locking block, and the protective cover is also provided with a stopper for cooperating with the second connecting rod when it is reversed to an extreme position, so as to push the protective cover to open upward under the continued drive of the direct-acting drive mechanism.

[0009] Furthermore, when the locking tongue is in a locked state, the fifth and sixth connecting rods are in a collinear dead point state.

[0010] Furthermore, the locking block includes a first locking plane for locking with the locking tongue, and the locking tongue is provided with a second locking plane corresponding to the first locking plane. When the locking tongue is in a locked state, the first locking plane and the second locking plane stop each other.

[0011] Furthermore, each locking plane is an inclined plane, and an end of the first locking plane close to the lock tongue is higher than an end away from the lock tongue.

[0012] Furthermore, the direct-acting drive mechanism is fixedly arranged on the frame, the output end of the direct-acting drive mechanism moves in the up and down direction, and a first connecting rod is hinged between the output end and one end of the second connecting rod to drive the second connecting rod to rotate forward and reversely when the output end moves up and down.

[0013] Furthermore, the direct-acting drive mechanism is an electric cylinder and a second motor for driving the electric cylinder to work, and the second motor is provided with a rotary encoder for recording the rotation angle of the second motor.

[0014] Furthermore, the direct-acting drive mechanism includes a vertically extending screw, a first motor that drives the screw to rotate, a vertically extending guide rod and a lifting member. The lifting member is provided with a threaded hole that cooperates with the screw and a guide hole that cooperates with the guide rod so that it can move up and down when the screw rotates. The lifting member constitutes the output end, and the first motor is provided with a rotary encoder for recording the rotation angle of the first motor.

[0015] Furthermore, the stopper is arranged near one end where the second connecting rod and the third connecting rod are hinged, so as to cooperate with the stopper at one end where the second connecting rod and the third connecting rod are hinged.

[0016] Furthermore, the second connecting rod is hinged at one end of the protective cover away from the rotation axis of the protective cover.

[0017] Furthermore, the transmission connecting rod includes a third connecting rod and a fourth connecting rod hinged together.

[0018] The beneficial effects of the protective cover opening and closing device of the present invention are as follows: the present invention is an improved invention. In the present invention, the protective cover is unlocked and driven to rise by a direct-acting drive mechanism and a connecting rod mechanism. During this process, only an "open" instruction needs to be issued to the direct-acting drive mechanism, which is convenient to operate. Accordingly, when the protective cover is to be driven to descend and locked, only an "close" instruction needs to be issued to the direct-acting drive mechanism, which is convenient to operate, and only one set of power mechanisms needs to be set, which is low in cost.

[0019] During use, the protective cover opening and closing device of the present invention is introduced by taking the protective cover being unlocked and raised as an example: In the initial state, the protective cover is locked; Afterwards, an "open" command is sent to the direct-acting drive mechanism, the output end of the direct-acting drive mechanism starts to move, the second connecting rod is reversed, and the lock tongue swings away from the locking block; After the output end moves until the lock tongue and the locking block are unlocked, the second connecting rod cooperates with the stopper. Since the second connecting rod is hinged to the protective cover, the relative position of the second connecting rod and the protective cover does not change when the output end continues to move. During the process of the output end continuing to move, the output end drives the second connecting rod to rise, and the second connecting rod pushes the protective cover to open upward. After the protective cover is opened to a set degree, the output end stops moving, thereby stopping the protective cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of the protective cover when the protective cover is locked in the specific embodiment 1 of the protective cover opening and closing device of the present invention; Figure 2 It is a structural schematic diagram of the protective cover when the protective cover is unlocked in the specific embodiment 1 of the protective cover opening and closing device of the present invention; Figure 3 for Figure 1 A magnified view of the structure at center A; Figure 4 for Figure 2 A magnified view of the structure at B in the middle; Figure 5 It is a schematic structural diagram of the protective cover when the protective cover is opened in the specific embodiment 1 of the protective cover opening and closing device of the present invention; Figure 6 It is a schematic structural diagram of the protective cover when the protective cover is locked in the specific embodiment 2 of the protective cover opening and closing device of the present invention; Figure 7 It is a schematic structural diagram of the protective cover when the protective cover is unlocked in the specific embodiment 2 of the protective cover opening and closing device of the present invention; Figure 8 It is a schematic structural diagram of the protective cover when it is opened in the specific embodiment 2 of the protective cover opening and closing device of the present invention.

[0021] Description of reference numerals: 1. Frame; 1-1. First support; 1-2. Second support; 1-3. Third support; 2. Protective cover; 3. Lock tongue; 3-1. Second locking plane; 4. Locking block; 4-1. First locking plane; 5-1. First connecting rod; 5-2. Second connecting rod; 5-3. Third connecting rod; 5-4. Fourth connecting rod; 5-5. Fifth connecting rod; 5-6. Sixth connecting rod; 6. Stopper; 7. Guide rod mounting seat; 8. Screw rod mounting seat; 9. Screw rod; 10. Guide rod; 11. Lifting member; 12. First motor; 13. Second motor; 14. Electric cylinder. DETAILED DESCRIPTION

[0022] To solve the problems in the background technology, the core inventive concept of the present invention is: in the process of the output end rising, the translation of the output end is converted into the swing of the lock tongue through the connecting rod mechanism, and after the protective cover is unlocked, the second connecting rod in the connecting rod mechanism cooperates with the protective cover stopper. Since the second connecting rod is hinged with the protective cover, the relative position of the second connecting rod and the protective cover does not change when the output end continues to rise, so that the output end drives the protective cover to open upward through the first connecting rod and the second connecting rod. Only one instruction is required to unlock and open the protective cover, and the operation is simple.

[0023] When the output end is at the lowest point, the fifth connecting rod and the sixth connecting rod are located on the same straight line. At this time, the four-link mechanism where the lock tongue is located is in a dead point state, thereby ensuring that the protective cover is locked.

[0024] The present invention is further described in detail below in conjunction with embodiments.

[0025] Specific embodiment 1 of the protective cover opening and closing device provided by the present invention: like Figure 1-5As shown, the protective cover opening and closing device includes a frame 1 and a protective cover 2 hinged at one end on the frame 1, a locking block 4 and a direct-acting drive mechanism that can translate the output end in the up-down direction and stop at a set position are provided on the frame 1, the protective cover opening and closing device also includes a lock tongue 3 that is used to lock and cooperate with the locking block 4 to lock the position of the protective cover 2 when the output end is at the lowest position, the lock tongue 3 is hinged on the inner side of the protective cover 2, and a connecting rod mechanism for converting the translation of the output end into the rotation of the lock tongue 3 is connected to the output end; The connecting rod mechanism includes a first connecting rod 5-1, a second connecting rod 5-2, a third connecting rod 5-3, a fourth connecting rod 5-4, a fifth connecting rod 5-5 and a sixth connecting rod 5-6. The middle part of the second connecting rod 5-2 is hinged to the protective cover 2, and the fifth connecting rod 5-5 is hinged to the inner side of the protective cover 2. The fifth connecting rod 5-5, the sixth connecting rod 5-6, the protective cover 2 and the lock tongue 3 constitute a four-link mechanism. When the output end is at the lowest point, the fifth connecting rod 5-5 and the sixth connecting rod 5-6 are located on the same straight line. One end of the first link 5-1 is hinged to the output end, and the other end is hinged to one end of the second link 5-2, the other end of the second link 5-2 is hinged to one end of the third link 5-3, the other end of the third link 5-3 is hinged to one end of the fourth link 5-4, and the other end of the fourth link 5-4 is hinged to the middle part of the fifth link 5-5, so as to drive the locking tongue 3 in the four-bar mechanism to swing away from the locking block 4 when the output end rises; wherein the third link 5-3 and the fourth link 5-4 hinged together constitute a transmission link, and the output end and the first link 5-1 drive the second link 5-2 to rotate forward and reversely. When the second link 5-2 rotates forward, the fifth link 5-5 is driven to rotate forward through the transmission link to make the locking tongue 3 move to the locked state, and when the second link 5-2 reverses, the locking tongue 3 is away from the locking block 4.

[0026] Specifically, the frame includes a first support 1-1, a second support 1-2 and a third support 1-3, the second connecting rod 5-2 is hinged on the first support 1-1, the fifth connecting rod 5-5 is hinged on the second support 1-2, and the locking tongue 3 is hinged on the third support 1-3.

[0027] The protective cover 2 is also provided with a stop portion 6 for cooperating with the second connecting rod 5-2 after the locking tongue 3 and the locking block 4 are unlocked, so that the second connecting rod 5-2 pushes the protective cover 2 to open upward (that is, the protective cover 2 is also provided with a stop portion 6 for cooperating with the second connecting rod 5-2 when it is reversed to the extreme position). The stop portion 6 is arranged near one end where the second connecting rod 5-2 and the third connecting rod 5-3 are hinged, so as to cooperate with the stop at one end where the second connecting rod 5-2 and the third connecting rod 5-3 are hinged, and the structure is simple.

[0028] In this embodiment, the protective cover 2 is unlocked and driven to rise by the direct-acting drive mechanism and the connecting rod mechanism. During this process, only the instruction "output end rises" needs to be sent to the direct-acting drive mechanism, which is convenient to operate. Correspondingly, when the protective cover 2 is driven to fall and locked, only the instruction "output end falls" needs to be sent to the direct-acting drive mechanism, which is convenient to operate.

[0029] During use, the protective cover opening and closing device of this embodiment is introduced by taking the protective cover 2 being unlocked and raised as an example: In the initial state, the output terminal is at the lowest position and the protective cover 2 is locked; Afterwards, the command "output end rises" is sent to the direct-acting drive mechanism, and the output end of the direct-acting drive mechanism starts to rise. The movement of the output end is transmitted to the lock tongue 3 through the connecting rod mechanism. When the output end rises, the lock tongue 3 swings away from the locking block 4 (that is, when the second connecting rod 5-2 is reversed, the lock tongue 3 moves away from the locking block 4); After the output end rises until the lock tongue 3 and the locking block 4 are unlocked, the second connecting rod 5-2 cooperates with the stopper 6. Since the middle part of the second connecting rod 5-2 is hinged with the protective cover 2, the relative position of the second connecting rod 5-2 and the protective cover 2 does not change when the output end continues to rise. In the process of the output end continuing to rise, the output end drives the first connecting rod 5-1 to rise, the first connecting rod 5-1 drives the second connecting rod 5-2 to rise, and the second connecting rod 5-2 pushes the protective cover 2 to open upwards; After the protective cover 2 is opened to a set degree, the output end stops moving, thereby causing the protective cover 2 to stop moving.

[0030] Correspondingly, when the output end descends, under the action of gravity, the protective cover 2 continues to descend. After the protective cover 2 descends to the lowest position, the second connecting rod 5-2 rotates forward and separates from the stopper 6, thereby driving the lock tongue 3 in the four-bar mechanism to swing toward the locking block 4 through the third connecting rod 5-3 and the fourth connecting rod 5-4 (that is, the lock tongue 3 is close to the locking block 4 when the second connecting rod 5-2 rotates forward).

[0031] When the output end is at the lowest point, the fifth link 5-5 and the sixth link 5-6 are located on the same straight line. At this time, the four-link mechanism where the lock tongue 3 is located is in a dead point state, and the lock tongue 3 moves to a locked state, thereby ensuring that the protective cover 2 is firmly locked.

[0032] However, in other specific embodiments, when the lock tongue 3 moves to the locked state, the fifth connecting rod 5-5 and the sixth connecting rod 5-6 may not be colinear. At this time, the lock tongue 3 and the locking block 4 can also lock the protective cover 2. Although the locking effect is poor, it can also meet the use requirements in non-harsh environments.

[0033] As a specific embodiment, the locking block 4 includes a first locking plane 4-1 for locking with the locking tongue 3, and the locking tongue 3 is provided with a second locking plane 3-1 corresponding to the first locking plane 4-1. When the output end is at the lowest point, the first locking plane 4-1 and the second locking plane 3-1 stop each other, with a simple structure and a good locking effect.

[0034] However, in other specific embodiments, one of the locking block 4 and the locking tongue 3 may have an outwardly protruding locking arc surface, and the other may have an inwardly recessed locking arc groove. When the output end is at the lowest point, the locking arc surface enters the locking arc groove and cooperates with the point stop of the bottom wall of the locking arc groove, thereby locking the protective cover 2.

[0035] In order to simplify the structure, as a specific implementation, each locking plane is an inclined plane, and the end of the first locking plane 4-1 close to the lock tongue 3 is higher than the end away from the lock tongue 3, and the structure is simple.

[0036] However, in other specific embodiments, the locking plane can also be located in the horizontal plane, or the end of the first locking plane 4-1 close to the lock tongue 3 can be lower than the end away from the lock tongue 3. The lock tongue 3 includes a lock tongue 3 body and an elastic pad fixed on the lock tongue 3 body, and one surface of the elastic pad constitutes the second locking plane 3-1. When the lock tongue 3 swings in the direction away from the locking block 4, the elastic pad can adaptively deform to increase the contact area between the first locking plane 4-1 and the second locking plane 3-1 while preventing the lock tongue 3 from being unable to swing in the direction away from the locking block 4.

[0037] In order to simplify the structure, the direct-acting drive mechanism includes a vertically extending screw rod 9, a first motor 12 for driving the screw rod 9 to rotate, a vertically extending guide rod 10 and a lifting member 11. The screw rod 9 and the guide rod 10 are respectively installed on the frame 1 through a screw rod mounting seat 8 and a guide rod mounting seat 7. The lifting member 11 is provided with a threaded hole that cooperates with the screw rod 9 and a guide hole that cooperates with the guide rod 10 so that it can move up and down when the screw rod 9 rotates. The lifting member 11 constitutes the output end. The lifting member 11 can be a lifting plate, a lifting block or a lifting rod and other structures, and the structure is simple.

[0038] In order to conveniently control the degree of opening of the protective cover 2, as a specific implementation, a rotary encoder for recording the rotation angle of the first motor 12 is provided on the first motor 12. The rotary encoder can also record the number of revolutions of the motor, thereby deriving the number of revolutions of the screw rod 9. The distance moved by the lifting member 11 can be derived from the number of revolutions of the screw rod 9, and then the degree of opening of the protective cover 2 can be derived. By controlling the number of revolutions of the first motor 12 according to the data of the rotary encoder, the degree of opening of the protective cover 2 can be accurately controlled.

[0039] However, in a usage environment where there is no precise requirement on the opening degree of the protective cover 2, the rotary encoder may not be provided.

[0040] In order to simplify the structure, as a specific implementation, the second connecting rod 5-2 is hinged at one end of the protective cover 2 away from the rotation axis of the protective cover 2, so that the second connecting rod 5-2 can push the protective cover 2 to open upward with a smaller force, and then the output end can push the first connecting rod 5-1, the second connecting rod 5-2 and the protective cover 2 to move upward with a smaller force, and the structure is simple.

[0041] However, in other specific embodiments, the second connecting rod 5-2 can also be hinged at the middle part of the protective cover 2 or on the side of the protective cover 2 close to its own rotation axis. In this case, it is necessary to increase the output power of the first motor 12, or to set a reducer between the first motor 12 and the screw 9 to increase the force applied by the output end to the first connecting rod 5-1, thereby increasing the force of the second connecting rod 5-2 to push the protective cover 2.

[0042] The rotation axis of the protective cover 2 is defined to extend along the front-to-back direction. Compared with the technical solution of only arranging a set of direct-acting drive mechanism, connecting rod mechanism, locking tongue 3 and locking block 4 at the front end or the rear end of the protective cover 2, as a specific implementation method, the number of the direct-acting drive mechanism, connecting rod mechanism, locking tongue 3 and locking block 4 is two sets, and they are respectively arranged at the front and rear ends of the protective cover 2, thereby reducing the requirement for the output power of a single first motor 12. At the same time, locking the protective cover 2 on both the front and rear sides can better prevent the corners of the protective cover 2 from warping up, thereby improving the sealing of the protective cover 2.

[0043] Specific embodiment 2 of the protective cover opening and closing device provided by the present invention: The purpose of this embodiment is to provide a protective cover opening and closing device with a different direct-acting drive mechanism.

[0044] In reference Figure 1-5 On the basis of Figure 6-8 As shown, the main difference between this embodiment and specific embodiment 1 is that: in specific embodiment 1, the direct-acting drive mechanism includes a first motor 12, a screw 9, a guide rod 10 and a lifting member 11, while in this embodiment, the direct-acting drive mechanism is an electric cylinder 14 and a second motor 13 driving the electric cylinder 14, and the output end of the electric cylinder 14 constitutes the output end of the direct-acting drive mechanism, and the structure is simple.

[0045] When the opening degree of the protective cover 2 needs to be accurately controlled, a rotary encoder for recording the rotation angle of the second motor 13 is further provided on the second motor 13 .

[0046] In other specific embodiments, when the accuracy of the opening degree of the protective cover 2 is not required, the rotary encoder may not be provided. In other specific embodiments, the output end of a direct-acting drive mechanism such as a hydraulic cylinder, an electric push rod, or a pneumatic cylinder may be hinged to the first connecting rod 5-1.

[0047] Specific embodiment 3 of the protective cover opening and closing device provided by the present invention: The purpose of this embodiment is to provide a protective cover opening and closing device with a different connecting rod mechanism.

[0048] Reference Figure 1-8 As shown, the main difference between this embodiment and specific embodiment 1 is that in specific embodiment 1, the connecting rod mechanism includes a first connecting rod 5-1, and the third connecting rod 5-3 and the fourth connecting rod 5-4 constitute a transmission connecting rod, while in this embodiment, the connecting rod mechanism does not include the first connecting rod 5-1, and the transmission connecting rod is only one rod.

[0049] In this embodiment, a first guide slot is provided on the output end, and the second connecting rod 5-2 is hinged in the first guide slot to convert the translation of the output end into the rotation of the second connecting rod; a second guide slot is provided on the fifth connecting rod 5-5, and the transmission connecting rod is hinged in the second guide slot to drive the four-bar linkage to move with one connecting rod. In this field, using guide slots to transmit the movement between connecting rods is a mature prior art and will not be described in detail here.

[0050] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments without creative work, or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A protective cover opening and closing device, comprising a frame and a protective cover hinged at one end to the frame, characterized in that: A locking block is provided on the side of the frame away from the hinged position of the protective cover, a locking tongue and a fifth connecting rod are hinged on the inner side of the protective cover, a sixth connecting rod is hinged between the locking tongue and the fifth connecting rod to form a four-bar linkage, the locking tongue has the function of cooperating with the locking block in the opening direction of the protective cover when the fifth and sixth connecting rods are rotated to a certain angle to keep the protective cover in a closed and locked state; a second connecting rod is also hinged on the protective cover, a direct-acting drive mechanism for controlling the forward and reverse rotation of one end of the second connecting rod is provided on the frame, the other end of the second connecting rod is hinged to the fifth connecting rod through a transmission connecting rod, when the second connecting rod rotates forward, the fifth connecting rod is driven to rotate forward through the transmission connecting rod to move the locking tongue to a locked state, when the second connecting rod reverses, the locking tongue is away from the locking block, and a stop portion is also provided on the protective cover for cooperating with the second connecting rod when it is reversed to the extreme position, so as to push the protective cover to open upward under the continued drive of the direct-acting drive mechanism.

2. The protective cover opening and closing device according to claim 1, characterized in that: When the lock tongue is in a locked state, the fifth and sixth connecting rods are in a collinear dead point state.

3. The protective cover opening and closing device according to claim 2, characterized in that: The locking block comprises a first locking plane for locking with the locking tongue, and the locking tongue is provided with a second locking plane corresponding to the first locking plane. When the locking tongue is in a locked state, the first locking plane and the second locking plane stop each other.

4. The protective cover opening and closing device according to claim 3, characterized in that: Each locking plane is an inclined plane, and an end of the first locking plane close to the lock tongue is higher than an end away from the lock tongue.

5. The protective cover opening and closing device according to any one of claims 1 to 4, characterized in that: The direct-acting drive mechanism is fixedly arranged on the frame, and the output end of the direct-acting drive mechanism moves in the up-down direction, and a first connecting rod is hinged between the output end and one end of the second connecting rod to drive the second connecting rod to rotate forward and reversely when the output end moves up and down.

6. The protective cover opening and closing device according to claim 5, characterized in that: The direct-acting drive mechanism is an electric cylinder and a second motor that drives the electric cylinder to work, and the second motor is provided with a rotary encoder for recording the rotation angle of the second motor.

7. The protective cover opening and closing device according to claim 5, characterized in that: The direct-acting drive mechanism includes a vertically extending screw, a first motor for driving the screw to rotate, a vertically extending guide rod and a lifting member. The lifting member is provided with a threaded hole that cooperates with the screw and a guide hole that cooperates with the guide rod so that it can move up and down when the screw rotates. The lifting member constitutes the output end, and the first motor is provided with a rotary encoder for recording the rotation angle of the first motor.

8. The protective cover opening and closing device according to any one of claims 1 to 4, characterized in that: The stopper is arranged close to one end where the second connecting rod and the third connecting rod are hinged, so as to cooperate with the stopper at one end where the second connecting rod and the third connecting rod are hinged.

9. The protective cover opening and closing device according to any one of claims 1 to 4, characterized in that: The second connecting rod is hinged at one end of the protective cover away from the rotation axis of the protective cover.

10. The protective cover opening and closing device according to any one of claims 1 to 4, characterized in that: The transmission connecting rod comprises a third connecting rod and a fourth connecting rod which are hinged together.

Images