A feeding mechanism for a traditional Chinese medicine formula granule medicine bag packing box

Abstract

The utility model relates to a kind of feeding mechanism for traditional Chinese medicine formula granule medicine bag packing box, and the utility model discloses a kind of feeding mechanism.For solving the problems of complex structure of prior art traditional Chinese medicine bag packing box equipment, inconvenient maintenance and debugging.The utility model includes chain conveyer belt, host computer, receiving plate, receiving wheel and material conveying groove, when receiving plate is in receiving state, it can be transferred to material conveying groove by the cooperation between receiving plate and receiving wheel, the process of medicine bag feeding does not need artificial counting, stacking, to avoid medicine bag scratch operator;The working state of receiving plate can be realized by the mutual cooperation between counting sensor, travel switch, double electric control solenoid valve, host computer and cylinder, and then the orderly feeding and discharging of medicine bag is realized, the structure of receiving plate, receiving wheel and material conveying groove is simple, and the control of each electronic component is realized by PLC controller, which brings convenience for later maintenance and debugging.The utility model belongs to the technical field of traditional Chinese medicine formula granule packing and feeding equipment.

Description

Technical Field

[0001] This invention relates to a feeding mechanism, specifically a feeding mechanism for packaging bags of traditional Chinese medicine formula granules, belonging to the technical field of packaging and feeding equipment for traditional Chinese medicine formula granules. Background Technology

[0002] Traditional Chinese medicine (TCM) formula granules are made from TCM decoction pieces through water extraction, separation, concentration, drying, and granulation processes. While maintaining the advantages of traditional TCM decoctions, they avoid the time-consuming and laborious drawbacks of decocting. After being prepared according to TCM clinical prescriptions, the TCM formula granules are packaged in three-side-sealed bags according to a certain dosage, making them individually packaged medicine bags for patients to take. They are lightweight, compact, easy to carry, and not easily affected by moisture.

[0003] Currently, the packaging of medicine bags still uses a semi-automated method. That is, the operators count out a specified number of medicine bags and then place these medicine bags on the packaging production line, which completes the packaging. This production method is inefficient, prone to errors, and because the seals of the medicine bags are sharp, workers are easily scratched when counting them.

[0004] Patent CN103112608B discloses a small-bag packaging product collection and quantitative filling system and packaging machinery containing the system. The patent's technical solution uses a robotic arm with a certain number of pushing plates. These pushing plates are fitted with gaps between themselves and partitions on the conveyor belt to push packaged products from the collection device's conveyor belt onto a feeding hopper. The pushing structure then pushes the packaged products from the feeding hopper onto a material bin on the conveyor belt. Finally, a cartoning plate delivers the grouped bagged products from the bin into packaging boxes. In this solution, the packaging products require not only the coordinated operation of the robotic arm and the pushing structure during transfer, but also that the pushing structure needs to perform sequential actions in both the horizontal and vertical directions during the pushing process. This increases the complexity of the system structure and makes subsequent maintenance and debugging difficult.

[0005] In summary, how to propose a feeding mechanism to address the aforementioned technical problems has become a pressing issue for those skilled in the art. Summary of the Invention

[0006] To address the shortcomings of the prior art, this invention provides a feeding mechanism for packaging bags of traditional Chinese medicine formula granules.

[0007] The technical solution of the present invention is: a feeding mechanism for packaging Chinese herbal medicine formula granules in bags, comprising a chain conveyor belt, a host computer, a receiving plate, and receiving wheels.

[0008] The chain conveyor belt has two rows of conveyor chains, the distance between which is less than the length or width of the medicine bag. Each row of conveyor chains is equipped with several material troughs for storing medicine bags, and the number and position of the material troughs are the same on both rows of conveyor chains. The material troughs are equipped with travel stops, which are arranged parallel to the conveyor chains. The travel stops have elongated holes and can be adjusted along the length of the conveyor chain.

[0009] The chain conveyor belt is driven intermittently by a stepper motor. The frame of the chain conveyor belt is fixed with a first column, a second column, a cylinder, a limit switch, a dual-electro-controlled solenoid valve, and a feeding chute for discharging medicine bags. The first column, the second column, and the feeding chute are arranged sequentially along the length of the frame, and the height of the first column is greater than the height of the second column.

[0010] The cylinder is mounted on the first column. The cylinder is pneumatically connected to the valve port of the dual-electro-controlled solenoid valve through a pipeline. Both the dual-electro-controlled solenoid valve and the limit switch are connected to the host computer for communication. The limit switch and the limit stop can retract the piston rod of the cylinder.

[0011] The receiving wheel is rotatably connected to the second column and is arranged between two rows of conveyor chains. The receiving wheel and the chain conveyor belt transmit power through a V-belt. The linear velocity of the outer diameter of the receiving wheel is the same as the conveying speed of the conveyor chain. Several elastic blades for receiving medicine bags are fixed on the outer circumference of the receiving wheel in a circular array.

[0012] The receiving plate is used to transport the medicine bag to the receiving wheel. The receiving plate is hinged to the second column, and the receiving plate has a notch for the rotation of the receiving wheel. The top surface of the first column and the piston rod of the cylinder both abut against the lower surface of the receiving plate. When the piston rod is retracted, the angle between the receiving plate and the horizontal plane is β.

[0013] A counting sensor is installed on the receiving plate. The counting sensor is connected to the host computer. The counting sensor and the host computer work together to enable the piston rod of the cylinder to extend. A baffle plate is fixed to the lower surface of the receiving plate.

[0014] Furthermore, the material conveying trough includes a first fixed material plate, a second fixed material plate, a movable material plate, and connecting bolts; the first fixed material plate is installed on the conveyor chain of the chain conveyor belt, and the first fixed material plate has an elongated hole, the movable material plate can slide along the length direction of the elongated hole, and the connecting bolts pass through the elongated hole and connect to the movable material plate; the second fixed material plate is integrally set with the first fixed material plate, and the included angle α between the second fixed material plate and the first fixed material plate is greater than 90° and less than 110°.

[0015] Furthermore, two medicine bag limiting baffles are installed on the receiving plate. The two medicine bag limiting baffles are respectively arranged on both sides of the receiving wheel, and both medicine bag limiting baffles are parallel to the receiving wheel. The two medicine bag limiting baffles can be relatively close or relatively far apart.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] This invention is easy to operate. When the receiving plate 200 is in the receiving state, the medicine bags can be transferred to the conveying trough 400 through the cooperation between the receiving plate 200 and the receiving wheel 300. The process of feeding medicine bags does not require manual counting and stacking, avoiding the medicine bags from scratching the operators. The working state of the receiving plate 200 can be realized through the cooperation between the counting sensor 210, the limit switch 140, the dual solenoid valve 150, the host computer 160 and the cylinder 111, thereby realizing the orderly feeding and unloading of medicine bags. The structure of the receiving plate 200, the receiving wheel 300 and the conveying trough 400 is simple, and the control of each electronic component is realized by the PLC controller, which brings convenience to the later maintenance and debugging. Attached Figure Description

[0018] Figure 1 This is an isometric view of the present invention;

[0019] Figure 2 This is a schematic diagram of the structure of the receiving plate 200, the baffle plate 220, the medicine bag limiting baffle 230, and the angle adjustable baffle 240 of the present invention;

[0020] Figure 3 This is a schematic diagram of the structure of the receiving plate 200, counting sensor 210, baffle plate 220, medicine bag limiting baffle 230, and angle adjustable baffle 240 of the present invention.

[0021] Figure 4 This is an isometric view of the material conveying trough 400 of the present invention;

[0022] Figure 5 This is an isometric view of the receiving wheel 300 of the present invention;

[0023] Figure 6 This is the first front view of the present invention;

[0024] Figure 7 This is the second front view of the present invention;

[0025] Figure 8 This is a schematic diagram showing the connection between the limit switch 140, the dual-electro-controlled solenoid valve 150, the host computer 160, and the counting sensor 210 of the present invention.

[0026] In the diagram: 100, chain conveyor belt; 110, first column; 111, cylinder; 120, second column; 130, feeding chute; 140, limit switch; 150, dual-electro-controlled solenoid valve; 160, host computer; 161, switching power supply; 162, PLC controller; 163, first intermediate relay; 164, second intermediate relay; 170, stepper motor; 200, receiving plate; 210, counting sensor; 220, baffle plate; 230, medicine bag limit baffle; 240, angle adjustable baffle; 300, receiving wheel; 310, elastic blade; 400, conveying chute; 410, first fixed material plate; 411, second fixed material plate; 420, movable material plate; 430, travel stop. Detailed Implementation

[0027] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments.

[0028] Specific implementation method one: Combining Figures 1 to 8 This embodiment describes a feeding mechanism for packaging traditional Chinese medicine formula granules in medicine bags, which includes a chain conveyor belt 100, a host computer 160, a receiving plate 200, and a receiving wheel 300.

[0029] The chain conveyor belt 100 has two rows of conveyor chains, the distance between the two rows of conveyor chains being less than the length or width of the medicine bag; each row of conveyor chains is equipped with several material troughs 400 for storing medicine bags, and the number and position of the material troughs 400 on both rows of conveyor chains are the same; a travel stop 430 is installed on the material trough 400, the travel stop 430 is arranged parallel to the conveyor chain, the travel stop 430 has an elongated hole, and the travel stop 430 can be adjusted along the length of the conveyor chain.

[0030] The chain conveyor belt 100 is intermittently driven by a stepper motor 170. The frame of the chain conveyor belt 100 is fixed with a first column 110, a second column 120, a cylinder 111, a limit switch 140, a dual-electro-controlled solenoid valve 150, and a discharge chute 130 for discharging medicine bags. The first column 110, the second column 120, and the discharge chute 130 are arranged sequentially along the length of the frame, and the height of the first column 110 is greater than the height of the second column 120.

[0031] Cylinder 111 is mounted on the first column 110. Cylinder 111 is pneumatically connected to the valve port of dual-electro-controlled solenoid valve 150 through a pipeline. Both dual-electro-controlled solenoid valve 150 and limit switch 140 are connected to the host computer 160 for communication. Limit switch 140 and limit stop 430 cooperate to realize the retraction of piston rod of cylinder 111.

[0032] The receiving wheel 300 is rotatably connected to the second column 120 and is arranged between two rows of conveyor chains. The receiving wheel 300 and the chain conveyor belt 100 transmit power through a V-belt. The linear velocity of the outer diameter of the receiving wheel 300 is the same as the conveying speed of the conveyor chain. Several elastic blades 310 for receiving medicine bags are fixedly connected to the outer circumference of the receiving wheel 300 in a circumferential array. The profile of the elastic blades 310 is involute or L-shaped, and the root of the elastic blades 310 is fixedly connected to the outer circumferential surface of the receiving wheel 300.

[0033] The receiving plate 200 is used to transport the medicine bag to the receiving wheel 300. The receiving plate 200 is hinged to the second column 120, and the receiving plate 200 has a notch for the rotation of the receiving wheel 300. The top surface of the first column 110 and the piston rod of the cylinder 111 both abut against the lower surface of the receiving plate 200. When the piston rod is retracted, the angle between the receiving plate 200 and the horizontal plane is β. This setting facilitates the transport of the medicine bag.

[0034] A counting sensor 210 is installed on the receiving plate 200. The counting sensor 210 is connected to the host computer 160. The counting sensor 210 and the host computer 160 work together to enable the piston rod of the cylinder 111 to extend. A baffle plate 220 is fixedly attached to the lower surface of the receiving plate 200.

[0035] In this embodiment, the dual-electro-controlled solenoid valve 150 is a two-position five-way dual-electro-controlled solenoid directional valve, which has two solenoid coils inside, namely the left-position solenoid coil and the right-position solenoid coil.

[0036] When the left-position solenoid coil is energized, the valve core switches to the left position. At this time, air enters the rodless chamber of cylinder 111, and the gas in the rod chamber is discharged to the atmosphere, causing the piston rod of cylinder 111 to extend. When the right-position solenoid coil is energized, the valve core switches to the right position. At this time, air enters the rod chamber of cylinder 111, and the gas in the rodless chamber is discharged to the atmosphere, causing the piston rod of cylinder 111 to retract.

[0037] In this embodiment, the host computer 160 includes a switching power supply 161, a PLC controller 162, a first intermediate relay 163, and a second intermediate relay 164.

[0038] The switching power supply 161 is an MS-60-24V / 2.5A switching power supply from Hong Kong Mingwei Electric Co., Ltd.

[0039] The PLC controller 162 is a Siemens S7-1200-1212C programmable controller.

[0040] The first intermediate relay 163 and the second intermediate relay 164 are both Chint JZX-22F type miniature electromagnetic relays.

[0041] The counting sensor 210 is a Shanghai HG-J18-T20N1 / 20L type laser through-beam sensor.

[0042] like Figure 8 As shown, when a predetermined number of medicine bags pass through the receiving plate 200, the transmission route of the communication signal is: counting sensor 210 → PLC controller 162 → first intermediate relay 163 → left position electromagnetic coil, thereby realizing the extension of the piston rod of cylinder 111.

[0043] When the travel stop 430 abuts against the contact of the travel switch 140, the transmission route of the communication signal is: travel switch 140 → PLC controller 162 → second intermediate relay 164 → right position electromagnetic coil, thereby realizing the retraction of the piston rod of cylinder 111.

[0044] Preferably, the first intermediate relay 163 and the second intermediate relay 164 are electrically interlocked by the program compilation function of the PLC controller 162. This configuration avoids the left and right electromagnetic coils from being energized at the same time.

[0045] Specific Implementation Method Two: Combining Figure 1 and Figure 4 This embodiment describes a material conveying trough 400 that includes a first fixed material plate 410, a second fixed material plate 411, a movable material plate 420, and connecting bolts.

[0046] The first fixed plate 410 is arranged parallel to the horizontal plane and is installed on the conveyor chain of the chain conveyor belt 100. The first fixed plate 410 has an elongated hole. The movable plate 420 is arranged perpendicular to the horizontal plane and can slide along the length of the elongated hole. The connecting bolt passes through the elongated hole and is connected to the movable plate 420.

[0047] The second fixing plate 411 is integrally formed with the first fixing plate 410, and the included angle α between the second fixing plate 411 and the first fixing plate 410 is greater than 90° and less than 110°.

[0048] This configuration serves two purposes: firstly, adjusting the distance between the movable material plate 420 and the second fixed material plate 411 facilitates the storage of different quantities of medicine bags in the conveying trough 400; secondly, due to the included angle α between the second fixed material plate 411 and the first fixed material plate 410, when the medicine bag enters the conveying trough 400, the side surface of the medicine bag abuts against the surface of the second fixed material plate 411, making the medicine bag stable within the conveying trough 400.

[0049] The other components and connections are the same as in Specific Implementation Method 1.

[0050] Specific implementation method three: Combining Figure 2 and Figure 3In this embodiment, two medicine bag limiting baffles 230 are installed on the receiving plate 200. The two medicine bag limiting baffles 230 are respectively arranged on both sides of the receiving wheel 300, and both medicine bag limiting baffles 230 are parallel to the receiving wheel 300. The two medicine bag limiting baffles 230 can be relatively close or relatively far apart. This arrangement facilitates the transportation of medicine bags of different sizes. Other components and connections are the same as in specific embodiments one or two.

[0051] Specific implementation method four: Combination Figure 2 and Figure 3 In this embodiment, an angle-adjustable baffle 240 is installed on the medicine bag limiting baffle 230, and the angle-adjustable baffle 240 is connected to the medicine bag limiting baffle 230 by screws.

[0052] Furthermore, the transmitter and receiver of the counting sensor 210 are respectively mounted on the angle-adjustable baffle 240 and the receiving plate 200.

[0053] Furthermore, the included angle between the angle-adjustable baffle 240 and the receiving plate 200 is γ, and the opening direction of the included angle γ is towards the direction of the incoming material from the medicine bag.

[0054] The other components and connections are the same as those in specific implementation methods one, two, or three.

[0055] Specific Implementation Method Five: Combining Figure 1 and Figure 6 In this embodiment, the angle β between the receiving plate 200 and the horizontal plane is 20° to 30°. Other components and connections are the same as in specific embodiments one, two, three, or four.

[0056] Working principle

[0057] This section is designed to hold 8 medicine bags per 400mm feed trough, and simultaneously... Figures 1 to 8 Explanation of the working principle of this invention:

[0058] This invention is used in conjunction with an air compressor, a material handling production line, and a packaging production line. When the piston rod of the cylinder 111 retracts, the receiving plate 200 is in the receiving state. In this state, the material handling production line can arrange the medicine bags in a single line and transport the medicine bags to the receiving plate 200 at a specific speed and spacing.

[0059] Because there is an angle β between the receiving plate 200 and the horizontal plane, the medicine bag enters the gap between the receiving wheel 300 and the elastic blade 310 after passing through the receiving plate 200. The counting sensor 210 is connected to the host computer 160 and can count the medicine bags passing through the receiving plate 200. The medicine bags are transported in the direction of the conveyor chain under the drive of the receiving wheel 300.

[0060] The receiving wheel 300 is arranged between two rows of conveyor chains, and the distance between the two rows of conveyor chains is less than the length or width of the medicine bag. Therefore, when the medicine bag enters the i-th conveying trough 400 (the i-th indicates the conveying trough 400 that is currently being filled), the bottom edge of the medicine bag abuts against the first fixed material plate 410, and the side surface of the medicine bag abuts against the surface of the second fixed material plate 411. As the receiving wheel 300 rotates, the medicine bag detaches from the receiving wheel 300 and completely enters the i-th conveying trough 400. At the same time, the i-th conveying trough 400 is gradually fed towards the discharge trough 130 under the drive of the conveyor chain. The medicine bags on the receiving wheel 300 are sequentially transferred to the i-th conveying trough 400. During this process, the outer surface of the elastic blade 310 pushes the medicine bags towards the second fixed material plate 411, so that each medicine bag is tightly abutted and neatly arranged on the conveying trough 400.

[0061] When eight medicine bags pass over the receiving plate 200, the host computer 160 sends a communication signal to the left electromagnetic coil of the dual-electro-controlled solenoid valve 150. Subsequently, air enters the rodless chamber of the cylinder 111, and the gas in the rod chamber is discharged to the atmosphere. The piston rod of the cylinder 111 extends, thereby causing the lower surface of the receiving plate 200 to detach from the top surface of the first column 110. At this time, the receiving plate 200 is detached from the discharge port of the material handling production line, and the receiving plate 200 is in a non-receiving state. The medicine bags discharged from the material handling production line are blocked and guided by the baffle plate 220, and then fall off along the baffle plate 220. A temporary storage box can be arranged below the baffle plate 220 to collect the fallen medicine bags, or a conveyor belt can be arranged below the baffle plate 220 to transport the fallen medicine bags back into the material handling production line.

[0062] When the i-th conveying trough 400 is filled with 8 medicine bags, it moves toward the unloading trough 130 under the drive of the conveyor chain; then the stroke stop 430 on the (i-1)-th conveying trough 400 (the (i-1)-th conveying trough 400 indicates that it is not currently loaded with material) first abuts against the contact of the limit switch 140, the host computer 160 sends a communication signal to the right electromagnetic coil of the dual-electro-controlled solenoid valve 150, then the rod chamber of the cylinder 111 is filled with air, the gas in the rodless chamber is discharged to the atmosphere, the piston rod of the cylinder 111 retracts, and then the lower surface of the receiving plate 200 abuts against the top surface of the first column 110, and the receiving plate 200 is in the receiving state again. With the drive of the conveyor chain, the receiving wheel 300 loads the (i-1)-th conveying trough 400 with material.

[0063] The chain conveyor belt 100 is intermittently driven by the stepper motor 170, thereby realizing intermittent conveying of the conveyor chain. The conveying speed of the conveyor chain is the same as that of the packaging production line. After the material trough 400, the unloading trough 130 and the medicine bag packaging box on the packaging production line are aligned, the chain conveyor belt 100 stops running. At the same time, the pusher on the packaging production line pushes the medicine bag on the material trough 400 into the medicine bag packaging box. After the medicine bag is unloaded from the material trough 400, the chain conveyor belt 100 continues to run. This process is repeated to achieve continuous feeding of medicine bags. When the chain conveyor belt 100 stops running, the i-th material trough 400 is already full of medicine bags, and the (i-1)-th material trough 400 has not yet been filled. Therefore, it does not affect the coordination between the receiving plate 200, the receiving wheel 300 and the material trough 400.

[0064] The present invention has been disclosed above with reference to preferred embodiments, but it is not intended to limit the present invention. Any simple modifications, equivalent changes and alterations made by those skilled in the art to the above embodiments without departing from the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A feeding mechanism for packaging bags of traditional Chinese medicine granules, characterized in that: It includes a chain conveyor belt (100), a host computer (160), a receiving plate (200), and a receiving wheel (300). The chain conveyor belt (100) has two rows of conveyor chains, the distance between the two rows of conveyor chains is less than the length or width of the medicine bag; each row of conveyor chains is equipped with several material troughs (400) for storing medicine bags, and the number and position of the material troughs (400) on the two rows of conveyor chains are the same; a travel stop (430) is installed on the material trough (400), the travel stop (430) is arranged parallel to the conveyor chain, the travel stop (430) has an elongated hole, and the travel stop (430) can be adjusted along the length direction of the conveyor chain; The material conveying trough (400) includes a first fixed material plate (410), a second fixed material plate (411), a movable material plate (420), and connecting bolts; The first fixed plate (410) is installed on the conveyor chain of the chain conveyor belt (100), and the first fixed plate (410) has an elongated hole. The movable plate (420) can slide along the length of the elongated hole. The connecting bolt passes through the elongated hole and connects to the movable plate (420). The second fixing plate (411) is integrally formed with the first fixing plate (410), and the included angle α between the second fixing plate (411) and the first fixing plate (410) is greater than 90° and less than 110°; The chain conveyor belt (100) is intermittently driven by a stepper motor (170). The frame of the chain conveyor belt (100) is fixed with a first column (110), a second column (120), a cylinder (111), a limit switch (140), a dual-electro-controlled solenoid valve (150), and a discharge chute (130) for discharging medicine bags. The first column (110), the second column (120), and the discharge chute (130) are arranged sequentially along the length of the frame, and the height of the first column (110) is greater than the height of the second column (120). The cylinder (111) is mounted on the first column (110). The cylinder (111) is pneumatically connected to the valve port of the dual-electro-controlled solenoid valve (150) through a pipeline. The dual-electro-controlled solenoid valve (150) and the limit switch (140) are both connected to the host computer (160). The limit switch (140) and the limit stop (430) work together to realize the retraction of the piston rod of the cylinder (111). The receiving wheel (300) is rotatably connected to the second column (120), and the receiving wheel (300) is arranged between two rows of conveyor chains. The receiving wheel (300) and the chain conveyor belt (100) transmit power through a V-belt. The linear velocity of the outer diameter of the receiving wheel (300) is the same as the conveying speed of the conveyor chain. Several elastic blades (310) for receiving medicine bags are fixed on the outer circumference of the receiving wheel (300) in a circular array. The material receiving plate (200) is used for conveying the medicine bag to the material receiving wheel (300), the material receiving plate (200) is hinged with the second stand (120), and the material receiving plate (200) is provided with an opening for the rotation of the material receiving wheel (300); the top surface of the first stand (110) and the piston rod of the air cylinder (111) are all abutted with the lower surface of the material receiving plate (200), and the included angle between the material receiving plate (200) and the horizontal plane is β 0-10° in the retracted state of the piston rod. A counting sensor (210) is installed on the receiving plate (200). The counting sensor (210) is connected to the host computer (160). The counting sensor (210) and the host computer (160) work together to enable the piston rod of the cylinder (111) to extend. A baffle plate (220) is fixed to the lower surface of the receiving plate (200).

2. The feeding mechanism for packaging traditional Chinese medicine granule bags according to claim 1, characterized in that: Two medicine bag limiting baffles (230) are installed on the receiving plate (200). The two medicine bag limiting baffles (230) are respectively arranged on both sides of the receiving wheel (300), and the two medicine bag limiting baffles (230) are parallel to the receiving wheel (300). The two medicine bag limiting baffles (230) can be relatively close or relatively far apart.

3. The feeding mechanism for packaging traditional Chinese medicine granules in a bag according to claim 2, characterized in that: An adjustable baffle (240) is installed on the medicine bag limiting baffle (230). The adjustable baffle (240) and the medicine bag limiting baffle (230) are connected by screws. The included angle between the adjustable baffle (240) and the receiving plate (200) is . γ .

4. The feeding mechanism for packaging traditional Chinese medicine granules in a bag according to claim 3, characterized in that: The angle between the receiving plate (200) and the horizontal plane β The angle is 20° to 30°.

Images