Multiple protection device for opening and closing barrel cover of mixing barrel
By using U-shaped safety blocks and multiple switches to monitor the position of the barrel cover in the mixing mixing equipment, the safety hazards of the barrel cover suddenly falling or not being properly covered on the mixing bucket are solved, achieving higher operating safety.
Patent Information
- Application Number
- CN202422024037.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-21
- Publication Date
- 2025-07-29
- Estimated Expiration
- 2034-08-21
AI Technical Summary
In existing mixing and mixing equipment, the barrel cover suddenly falls off due to failure or other factors or is not properly covered on the mixing barrel, which poses a safety hazard and cannot effectively ensure the safety of the operator.
A multi-protective device for opening and closing of the mixing barrel cover is designed, and the rising barrel cover is supported by a U-shaped safety block, and the position and locking status of the barrel cover are monitored through multiple stroke switches and proximity switches to ensure that the barrel cover is correctly covered on the mixing barrel before the equipment can be started.
Accurate monitoring and control of the position and locking status of the barrel cover is realized, reducing safety hazards and improving operational safety.
Smart Images
Figure CN223159184U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of stirring and mixing equipment, in particular to a multiple protection device for opening and closing the cover of a mixing barrel. Background Technique
[0002] Stirring and mixing equipment is a common equipment in industrial production, used for mixing and stirring various materials. During the operation of stirring and mixing equipment, safety accidents are likely to occur due to improper operation, imperfect safety facilities and other factors. To ensure the life safety of operators, the current safety measures for stirring and mixing equipment are mainly as follows: one is regular maintenance to ensure the normal operation of stirring and mixing equipment; the second is to formulate operating procedures and require operators to wear protective equipment such as safety helmets and protective glasses, so that operators can complete the operation process in an orderly manner to ensure the safety of the production process and the normal operation of the equipment; the third is to set up guardrails around the mixing barrel to prevent workers from straying into it and causing injuries during the operation of stirring and mixing equipment; the fourth is to set obvious safety warning signs around the stirring and mixing equipment, indicating that it is prohibited to approach during the operation of stirring and mixing equipment; the fifth is that the stirring and mixing equipment is equipped with an emergency stop switch to facilitate stopping the operation of the stirring and mixing equipment immediately in case of emergency. However, for the stirring and mixing equipment with the cover pushed upward by a cylinder to open and pulled downward to close, there is still a problem that the cover that was originally in the open state suddenly drops due to a fault or other factors after the cover is opened. At this time, the operator may be near the mixing barrel or may be performing operations such as repairing the inside of the mixing barrel, etc., which poses a safety hazard. In addition, there are also problems such as the cover not being covered on the mixing barrel in the correct position and the cover not being locked with the mixing barrel, etc. These problems can only be discovered by the operator through visual observation. If the operator fails to notice due to negligence, safety accidents are likely to occur. Content of the Utility Model
[0003] The technical problem to be solved by the utility model is to provide a multiple protection device for opening and closing the cover of a mixing barrel with good safety performance. Through this device, it is ensured that the stirring and mixing equipment can only be started and operated when the cover is correctly and tightly covered on the mixing barrel.
[0004] The multi-protection device for opening and closing the mixing barrel lid described in this solution is designed for mixing and stirring equipment in which the lid is pushed upward by a cylinder to open the mixing barrel and pulled downward to close the mixing barrel. The rising lid is supported by a U-shaped safety support block, so that the lid will not fall suddenly due to a malfunction or other factors. In addition, the lid rotates horizontally after rising under the action of an external force, causing the lid to shift to one side, exposing the top of the mixing barrel so that subsequent operations can be carried out. When the mixing and stirring equipment needs to operate normally, the shifted lid must first be pushed back to its original position, and then the lid is pulled onto the mixing barrel by the cylinder. At this time, the lid is correctly covered on the mixing barrel. In order to monitor whether the lid is correctly covered on the mixing barrel and whether the U-shaped safety support block has returned to its original position, multiple travel switches and proximity switches are matched for real-time monitoring.
[0005] At present, the connection structure between the barrel cover and the mixing barrel in the mixing and mixing equipment in which the mixing barrel is pushed upward by a cylinder to open and pulled downward to close the mixing barrel is as follows: the cylinder body of the cylinder is fixed on the outer barrel wall of the mixing barrel and the piston rod of the cylinder points upward, and the bearing seat is fixed to the top of the piston rod of the cylinder through the bearing cover at the bottom; a connecting seat with a connecting hole is provided on the barrel cover, and the bottom of the rotating shaft passes through the connecting hole and the bushing in sequence and extends into the bearing seat, and is fixedly connected to the inner ring of the bearing in the bearing seat, and an external threaded section is provided on the upper section of the rotating shaft. After the top of the rotating shaft extends above the connecting hole, it passes through the gasket and is tightened with the locking nut; a positioning pin is provided on the connecting seat, and a positioning plate with a positioning hole is provided on the outer barrel wall of the mixing barrel. When the barrel cover is correctly covered on the mixing barrel, the positioning pin is inserted into the positioning hole.
[0006] Building on the existing structure, this solution features a rack fixed to the outer wall of the mixing barrel, a U-shaped safety support resting on the rack, and a first travel switch or proximity switch mounted on the outer wall or the rack. When the U-shaped safety support rests on the rack, it presses against the contacts of the first travel switch or is within the sensing area of the first proximity switch. When the cylinder drives the lid upward, the U-shaped safety support engages the gap between the bearing cap and the top of the cylinder. The lid is then pushed horizontally, pivoting to one side. This prevents the lid from suddenly falling due to a malfunction or other factors, ensuring the safety of subsequent operators.
[0007] A second travel switch is installed on the outer barrel wall of the mixing barrel. When the lid is properly placed on the mixing barrel at the position where the second travel switch is located, the connecting seat presses on the contact of the second travel switch. A second proximity switch is installed on the outer barrel wall of the mixing barrel. When the positioning pin inserted into the positioning hole is within the sensing area of the second proximity switch at the position where the second proximity switch is located, and the positioning pin after disengaging upward from the positioning hole is outside the sensing area of the second proximity switch. A third proximity switch is installed on the outer barrel wall of the mixing barrel. When the lid is placed on the mixing barrel at the position where the third proximity switch is located, the bearing block is within the sensing area of the third proximity switch, and when the lid rises driven by the cylinder, the bearing block is outside the sensing area of the third proximity switch.
[0008] The signal lines of the first travel switch or the first proximity switch, the signal line of the second travel switch, the signal line of the second proximity switch, and the signal line of the third proximity switch are all connected to the control system. The control system can receive the signals fed back by the first travel switch or the first proximity switch, the second travel switch, the second proximity switch, and the third proximity switch, and make judgments, so as to control whether the subsequent operator can start the stirring and mixing equipment when starting.
[0009] Furthermore, for the above-mentioned multiple protection device for opening and closing the lid of the mixing barrel, a first support plate and a second support plate are installed on the outer barrel wall of the mixing barrel. The two ends of the bottom surface of the positioning plate are respectively fixed on the top of the first support plate and the top of the second support plate, and the second proximity switch is installed on the first support plate or the second support plate.
[0010] It is impossible for the lid to be completely sealed with the mixing barrel only by relying on the cylinder. Therefore, in this solution, a locking device for locking the lid on the mixing barrel is provided between the outer barrel wall of the mixing barrel and the lid. The locking device is composed of several locking mechanisms. The structure of each locking mechanism is as follows: A locking block is fixedly arranged on the lid, and a locking groove in the shape of a semi-circular channel is opened on the top surface of the locking block. An installation seat is fixedly arranged on the outer barrel wall of the mixing barrel below the locking block. The front end of the handle is hinged to the installation seat. Threaded sections are respectively arranged at both ends of the rectangular buckle formed by bending a round rod. The pin shaft is movably inserted through the through hole on the handle, and both ends of the pin shaft extend out of the through hole on the handle. A connecting through hole is respectively opened at both ends of the pin shaft extending out of the through hole on the handle. The threaded sections at both ends of the rectangular buckle are respectively inserted through the corresponding connecting through holes and are respectively fixed to the pin shaft by two nuts. When the handle swings relative to the hinge point between the handle and the installation seat, the rectangular buckle can be clamped with the locking groove or disengaged from the locking groove.
[0011] Furthermore, a fourth proximity switch is installed on the outer barrel wall of the mixing barrel at at least one locking mechanism. The position of each fourth proximity switch is such that when the rectangular buckle in the corresponding locking mechanism is clamped with the locking groove, the position of the pin shaft is within the sensing area of the fourth proximity switch, and when the rectangular buckle is disengaged from the locking groove, the position of the pin shaft is outside the sensing area of the fourth proximity switch; the signal wire of the fourth proximity switch is connected to the control system. The control system can receive the signal fed back by the fourth proximity switch and make a judgment.
[0012] Condition 1: When the U-shaped safety support block is located on the storage rack, the contact of the first travel switch is triggered or the first proximity switch senses the U-shaped safety inner support block; Condition 2: When the bucket lid is correctly covered on the mixing barrel, the connecting seat presses on the contact of the second travel switch to trigger the second travel switch; Condition 3: The second proximity switch senses the positioning pin (at this time, the positioning pin is inserted into the positioning hole); Condition 4: The third proximity switch senses the bearing seat (at this time, the bucket lid is covered on the mixing barrel); Condition 5: Each fourth proximity switch senses the corresponding pin shaft (at this time, the corresponding locking mechanism locks the bucket lid and the mixing barrel). When the control system detects that all the above five conditions are met, the control system controls the stirring and mixing equipment at this time, allowing it to be started. If any one of the above five conditions is not met, the control system controls the stirring and mixing equipment at this time, making it unable to start.
[0013] Further, in the above-mentioned multiple protection device for opening and closing the bucket lid of the mixing barrel, the end of the piston rod of the cylinder is fixedly connected with a movable shaft. The diameter of the movable shaft is larger than the diameter of the piston rod of the cylinder. The bearing seat is fixed to the top of the movable shaft through the bearing cover at the bottom, and the outer cylinder body sleeved on the movable shaft is fixed to the cylinder body of the cylinder; after the bucket lid is opened, the gap between the bearing cover and the outer cylinder body is just enough for the U-shaped safety support block to be inserted. An identification strip for identifying the position where the U-shaped safety support block is inserted after the bucket lid is opened is arranged on the outer side wall at the top of the outer cylinder body, and an identification coating with the same color as the identification strip is coated on the U-shaped safety support block.
[0014] To facilitate the operator to grasp the U-shaped safety support block, a handle for the hand to grasp is arranged on the U-shaped safety support block in this solution. On this basis, a plastic sleeve or a rubber sleeve can also be wrapped on the handle to improve the comfort of grasping and also play an anti-slip role.
[0015] The beneficial effects of the present utility model are: By using the U-shaped safety support block, the first travel switch or the first proximity switch, the second travel switch, the second proximity switch, the third proximity switch, and the fourth proximity switch, and relying on the control and monitoring of the control system, compared with the traditional method of the operator observing with the naked eye, it is precisely controllable and has better safety, greatly reducing potential safety hazards. Description of the Drawings
[0016] Figure 1The utility model is a structural schematic diagram of a mixing barrel cover opening and closing multiple protection device.
[0017] Figure 2 yes Figure 1 Schematic diagram of the locally enlarged structure of part A.
[0018] Figure 3 This is a structural schematic diagram of the mixing barrel cover opening and closing multiple protection device described in the utility model when it is in another observation direction.
[0019] Figure 4 yes Figure 3 Schematic diagram of the locally enlarged structure of part B.
[0020] Figure 5 yes Figure 3 Schematic diagram of the locally enlarged structure of part C.
[0021] Figure 6 It is a schematic diagram of the connection structure between the barrel cover and the mixing barrel.
[0022] Among them: 1. Mixing barrel; 11. Positioning plate; 12. Positioning hole; 13. First support plate; 14. Second support plate; 15. Mounting seat; 2. Barrel cover; 21. Connecting seat; 22. Connecting hole; 23. Bushing; 24. Positioning pin; 25. Locking block; 26. Locking groove; 3. Cylinder; 4. Bearing seat; 41. Bearing cover; 5. Rotating shaft; 51. External thread section; 52. Gasket; 53. Locking nut; 6. Storage rack; 61. U-shaped safety support block; 62. Handle; 71. First proximity switch; 72. Second travel switch; 73. Second proximity switch; 74. Fourth proximity switch; 75. Third proximity switch; 8. Handle; 81. Rectangular buckle; 82. Pin shaft; 83. Nut; 9. Movable shaft; 91. Outer cylinder; 92. Identification strip. DETAILED DESCRIPTION
[0023] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments.
[0024] The mixing barrel lid opening and closing multiple protection device described in this embodiment is as follows: Figure 1 、 Figure 3 and Figure 6As shown in the figure, it includes a mixing barrel 1 and a barrel cover 2. At least one sealing ring is provided on the bottom surface of the barrel cover 2, and the barrel cover 2 is hermetically sealed at the top open end of the mixing barrel 1 through each sealing ring. The connection structure between the barrel cover 2 and the mixing barrel 1 is as follows: The cylinder body of the cylinder 3 is fixed on the outer barrel wall of the mixing barrel, and the piston rod of the cylinder 3 points upward. The bearing seat 4 is fixed to the top of the piston rod of the cylinder 3 through the bearing cover 41 at the bottom; A connecting seat 21 with a connecting hole 22 is provided on the barrel cover 2. The bottom of the rotating shaft 5 sequentially passes through the connecting hole 22 and the bushing 23 and then extends into the bearing seat 4, and is fixedly connected to the inner ring of the bearing in the bearing seat 4. An external thread section 51 is provided on the upper section of the rotating shaft 5. After the top of the rotating shaft 5 extends above the connecting hole 22, it passes through the gasket 52 and is screwed tightly with the locking nut 53; A positioning pin 24 is provided on the connecting seat 21, and a positioning plate 11 with a positioning hole 12 is provided on the outer barrel wall of the mixing barrel 1. When the barrel cover 2 is correctly covered on the top open end of the mixing barrel 1, the positioning pin 24 is inserted into the positioning hole 12. As Figure 5 and Figure 6 shown in the figure, a storage rack 6 is fixedly provided on the outer barrel wall of the mixing barrel 1. The U-shaped safety support block 61 is placed on the storage rack 6. The function of the U-shaped safety support block 6 is as follows: After the cylinder 3 drives the barrel cover 2 to open upward, the operator needs to perform a series of operations inside or near the mixing barrel 1. To ensure the personal safety of the operator, the U-shaped safety support block 61 is stuck in the gap between the bearing cover 41 and the top of the cylinder 3. In this way, the U-shaped safety support block 6 can support the barrel cover 2, and the barrel cover 2 will not suddenly fall due to the failure of the cylinder 3 or other factors.
[0025] A more preferred method is that a movable shaft 9 is fixedly connected to the end of the piston rod of the cylinder 3. The diameter of the movable shaft 9 is larger than the diameter of the piston rod of the cylinder 3. The bearing seat 4 is fixed to the top of the movable shaft 9 through the bearing cover 41 at the bottom. The outer cylinder 91 sleeved on the movable shaft is fixed to the cylinder body of the cylinder 3; The gap between the bearing cover 41 and the outer cylinder 91 after the barrel cover 2 is opened is just for the U-shaped safety support block 61 to be inserted. An identification strip 92 for identifying the position where the U-shaped safety support block 61 is stuck after the barrel cover 2 is opened is provided on the outer side wall of the top end of the outer cylinder 91. An identification coating with the same color as the identification strip 92 is coated on the U-shaped safety support block 61.
[0026] In addition, to facilitate the operator to grasp the U-shaped safety support block 61, a handle 62 for the operator to grasp is provided on the U-shaped safety support block 61. On this basis, a plastic sleeve or a rubber sleeve can also be wrapped on the handle 62.
[0027] As Figure 5As shown in the figure, in this embodiment, a first travel switch or a first proximity switch 71 is installed on the outer barrel wall of the mixing barrel 1 or on the storage rack 6. When a first travel switch is adopted, when the U-shaped safety support block 61 is placed on the storage rack 6, the U-shaped safety support block 61 will press on the contact of the first travel switch. When a first proximity switch 71 is adopted, when the U-shaped safety support block 61 is placed on the storage rack 6, the U-shaped safety support block 61 is within the sensing area of the first proximity switch, and when the U-shaped safety support block 61 is taken away from the storage rack 6, the U-shaped safety support block 61 is outside the sensing area of the first proximity switch.
[0028] As Figure 3 and Figure 4 As shown in the figure, in this embodiment, a second travel switch 72 is installed on the outer barrel wall of the mixing barrel 1. The position of the second travel switch 72 is such that when the barrel cover 2 is correctly covered on the mixing barrel 1, the connecting seat 21 presses on the contact of the second travel switch 72; a second proximity switch 73 is installed on the outer barrel wall of the mixing barrel 1. The position of the second proximity switch 73 is such that the positioning pin 24 inserted into the positioning hole 12 is within the sensing area of the second proximity switch 73, and the positioning pin 24 after disengaging upward from the positioning hole 12 is outside the sensing area of the second proximity switch 73.
[0029] A more preferred solution is as Figure 4 shown in the figure. A first support plate 13 and a second support plate 14 are installed on the outer barrel wall of the mixing barrel 1. Both ends of the bottom surface of the positioning plate 11 are respectively fixed on the top of the first support plate 13 and the top of the second support plate 14. The second proximity switch 73 is installed on the first support plate 13 or the second support plate 14.
[0030] As Figure 3 and Figure 4 shown in the figure, in this embodiment, a third proximity switch 75 is installed on the outer barrel wall of the mixing barrel 1. The position of the third proximity switch 75 is such that when the barrel cover 2 is covered on the mixing barrel 1, the bearing seat 4 is within the sensing area of the third proximity switch 75, and when the barrel cover 2 rises driven by the cylinder 3, the bearing seat 4 is outside the sensing area of the third proximity switch 75.
[0031] In addition, it is impossible for the barrel cover 2 to be completely sealed with the mixing barrel 1 only by relying on the cylinder 3 because there will be factors such as vibration during the operation of the mixing barrel 1. Therefore, in this embodiment, a locking device for locking the barrel cover 2 to the mixing barrel 1 is provided between the outer barrel wall of the mixing barrel 1 and the barrel cover 2. The locking device is composed of a number of locking mechanisms; as Figure 1 and Figure 2As shown, the structure of each locking mechanism described in this embodiment is as follows: a locking block 25 is fixedly provided on the barrel cover 2, and a locking groove 26 in the shape of a semicircular channel is provided on the top surface of the locking block 25; a mounting seat 15 is fixedly provided on the outer barrel wall of the mixing barrel 1 below the locking block 25, and the front end of the handle 8 is hingedly connected to the mounting seat 15, and the two end ends of the rectangular buckle 81 formed by bending a round rod are respectively provided with threaded sections, and the pin shaft 82 is movably inserted into the through hole on the handle 8 and the two ends of the pin shaft 82 extend out of the through hole on the handle 8, respectively. A connecting through hole is provided at each end of the pin shaft 82 extending out of the through hole of the handle 8, and the threaded sections at both ends of the rectangular buckle 81 are respectively inserted into the corresponding connecting through holes and are respectively fixed to the pin shaft 82 by two nuts 83; when the handle 8 swings relative to the hinge point between the handle 8 and the mounting seat 15, the rectangular buckle 81 can be clamped with the locking groove 26 or the rectangular buckle 81 can be disengaged from the locking groove 26.
[0032] In this embodiment, a fourth proximity switch 74 is installed on the outer barrel wall of the mixing barrel 1 located at at least one locking mechanism. The position of each fourth proximity switch 74 is such that when the rectangular buckle 81 in the corresponding locking mechanism is engaged with the locking groove 26, the position of the pin 82 is located within the sensing area of the fourth proximity switch 74, and when the rectangular buckle 81 is disengaged from the locking groove 26, the position of the pin 82 is located outside the sensing area of the fourth proximity switch 74.
[0033] Among them, the signal line of the first travel switch or the first proximity switch 71, the signal line of the second travel switch 72, the signal line of the second proximity switch 73, the signal line of the third proximity switch 75, and the signal line of the fourth proximity switch 74 are all connected to the control system. The control system can receive the signal fed back by the first travel switch or the first proximity switch 71, the signal fed back by the second travel switch 72, the signal fed back by the second proximity switch 73, the signal fed back by the third proximity switch 75, and the signal fed back by the fourth proximity switch 74, and make a judgment, so as to control whether the subsequent operator can start the stirring and mixing equipment. Specifically,
[0034] Condition 1: When the U-shaped safety support block 61 is located on the storage rack 6, the contact of the first travel switch is triggered or the first proximity switch 71 senses the U-shaped safety inner support block 61; Condition 2: When the bucket lid 2 covers the mixing bucket 1, the connecting seat 21 presses on the contact of the second travel switch 72, triggering the second travel switch 72; Condition 3: The second proximity switch 73 senses the positioning pin 24 (at this time, the positioning pin 24 is inserted into the positioning hole 12); Condition 4: The third proximity switch 75 senses the bearing seat 4 (at this time, the bucket lid 2 is hermetically covered on the mixing bucket 1); Condition 5: Each third proximity switch 74 senses the corresponding pin shaft 82 (at this time, the corresponding locking mechanism locks the bucket lid 2 and the mixing bucket 1). When the control system detects that all the above five conditions are met, the control system controls the stirring and mixing equipment at this time, allowing it to be started. When the operator presses the start button of the stirring and mixing equipment, the stirring and mixing equipment can operate normally. If any one of the above five conditions is not met, the control system controls the stirring and mixing equipment at this time, making it unable to start. Even if the operator presses the start button of the stirring and mixing equipment, the stirring and mixing equipment still cannot be started.
[0035] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0036] The above are only the preferred embodiments of the present invention, and do not impose any other form of limitation on the present invention. Any modification or equivalent change made according to the technical essence of the present invention still belongs to the scope of protection required by the present invention.
Claims
1. A multi - protection device for opening and closing the lid of a mixing barrel, comprising: Mixing barrel and barrel cover; the connection structure between the barrel cover and the mixing barrel is as follows: the cylinder body of the air cylinder is fixed on the outer barrel wall of the mixing barrel and the piston rod of the air cylinder points upward, and the bearing seat is fixed on the top of the piston rod of the air cylinder through the bearing cover at the bottom; a connecting seat with a connection hole is arranged on the barrel cover, the bottom of the rotating shaft sequentially passes through the connection hole and the bushing and then extends into the bearing seat, and is fixedly connected with the inner ring of the bearing in the bearing seat. An external thread section is arranged on the upper section of the rotating shaft. After the top of the rotating shaft extends above the connection hole, it passes through the gasket and is screwed tightly with the locking nut; a positioning pin is arranged on the connecting seat, and a positioning plate with a positioning hole is arranged on the outer barrel wall of the mixing barrel. When the barrel cover is correctly covered on the mixing barrel, the positioning pin is inserted into the positioning hole; it is characterized in that: a storage rack is fixedly arranged on the outer barrel wall of the mixing barrel, and a U-shaped safety support block for being stuck in the gap between the bearing cover and the top of the air cylinder after the air cylinder drives the barrel cover to open upward is placed on the storage rack. A first travel switch or a first proximity switch is installed on the outer barrel wall of the mixing barrel or on the storage rack. When the U-shaped safety support block is placed on the storage rack, it presses on the contact of the first travel switch or when the U-shaped safety support block is placed on the storage rack, it is located in the sensing area of the first proximity switch; A second travel switch is installed on the outer barrel wall of the mixing barrel, and the position of the second travel switch is such that when the barrel cover is correctly covered on the mixing barrel, the connecting seat presses on the contact of the second travel switch; A second proximity switch is installed on the outer barrel wall of the mixing barrel. The position of the second proximity switch is such that the positioning pin inserted into the positioning hole is located in the sensing area of the second proximity switch, and the positioning pin after being disengaged from the positioning hole upward is located outside the sensing area of the second proximity switch; A third proximity switch is installed on the outer barrel wall of the mixing barrel. The position of the third proximity switch is such that when the barrel cover is covered on the mixing barrel, the bearing seat is located in the sensing area of the third proximity switch, and when the barrel cover rises under the drive of the air cylinder, the bearing seat is located outside the sensing area of the third proximity switch; The signal wires of the first travel switch or the first proximity switch, the signal wire of the second travel switch, the signal wire of the second proximity switch, and the signal wire of the third proximity switch are all connected to the control system.
2. The multiple protection device for opening and closing the mixing barrel lid according to claim 1, wherein: A first support plate and a second support plate are installed on the outer barrel wall of the mixing barrel. The two ends of the bottom surface of the positioning plate are respectively fixed on the top of the first support plate and the top of the second support plate, and the second proximity switch is installed on the first support plate or the second support plate.
3. The multiple protection device for opening and closing the mixing barrel lid according to claim 1, characterized in that: A locking device for locking the barrel cover onto the mixing barrel is provided between the outer barrel wall of the mixing barrel and the barrel cover. The locking device is composed of a number of locking mechanisms. The structure of each locking mechanism is as follows: A locking block is fixedly arranged on the barrel cover, and a locking groove in the shape of a semi-circular channel is formed on the top surface of the locking block. An installation seat is fixedly arranged on the outer barrel wall of the mixing barrel below the locking block. The front end of a handle is hinged to the installation seat. Threaded sections are respectively arranged at both ends of a rectangular buckle formed by bending a round rod. A pin shaft is movably inserted through a through hole on the handle, and both ends of the pin shaft respectively extend out of the through hole on the handle. A connecting through hole is respectively formed at both ends of the pin shaft extending out of the through hole of the handle. The threaded sections at both ends of the rectangular buckle are respectively inserted through the corresponding connecting through holes and are respectively fixed to the pin shaft by two nuts. When the handle swings relative to the hinge point between the handle and the installation seat, the rectangular buckle can be clamped with the locking groove or separated from the locking groove.
4. A multiple protection device for opening and closing the lid of a mixing barrel according to claim 3, characterized in that: A fourth proximity switch is installed on the outer barrel wall of the mixing barrel at at least one locking mechanism. When the rectangular buckle in the corresponding locking mechanism is clamped with the locking groove, the position of the pin shaft is within the sensing area of the fourth proximity switch, and when the rectangular buckle is separated from the locking groove, the position of the pin shaft is outside the sensing area of the fourth proximity switch. The signal wire of the fourth proximity switch is connected to the control system.
5. The multi - protection device for opening and closing the lid of the mixing barrel according to claim 1, characterized in that: The end of the piston rod of the cylinder is fixedly connected with a movable shaft. The diameter of the movable shaft is larger than the diameter of the piston rod of the cylinder. The bearing seat is fixed to the top of the movable shaft through a bearing cover at the bottom. An outer cylinder body sleeved on the movable shaft is fixed to the cylinder body of the cylinder. The gap between the bearing cover and the outer cylinder body after the barrel cover is opened is for the U-shaped safety support block to be inserted. An identification strip for identifying the position where the U-shaped safety support block is inserted after the barrel cover is opened is arranged on the outer side wall at the top of the outer cylinder body. An identification coating with the same color as the identification strip is coated on the U-shaped safety support block.
6. The multi - protection device for opening and closing the lid of the mixing barrel according to claim 1 or 5, characterized in that: A handle for human hands to grip is arranged on the U-shaped safety support block.
7. The multiple protection device for opening and closing the mixing barrel lid according to claim 6, wherein: A plastic sleeve or a rubber sleeve is wrapped on the handle.