Air duct cloth double-edge-folding mechanism and double-edge-folding method

Abstract

The invention relates to the field of mining air ducts, in particular to an air duct cloth double-edge-folding mechanism and a double-edge-folding method.The air duct cloth double-edge-folding mechanism comprises a feeding device used for conveying air duct cloth, the mechanism comprises a conveying frame body, the conveying frame body comprises a horizontal conveying frame and a vertical conveying frame, and a first edge folding device is arranged on the vertical conveying frame; the first edge folding device is used for folding one side of the air duct cloth; a second edge folding device is arranged on the horizontal conveying frame and used for folding the other side of the air duct cloth, through the combined design of the vertical conveying frame and the horizontal conveying frame, edge folding operation of the two sides is completed while continuous conveying of the air duct cloth is achieved, the problems of manual adjustment and repeated fixing in a traditional process are solved, the production efficiency is improved, and the production cost is reduced. The processing efficiency is greatly improved; according to the design of the device, the space utilization rate is fully considered, by integrating the edge folding function and the conveying function, the equipment layout is more compact, the occupied area is reduced, and the device is suitable for being used in a production workshop with limited space.

Description

Technical Field

[0001] The invention relates to the technical field of mine air ducts, in particular to a double-folding mechanism and a double-folding method for air duct cloth. Background Art

[0002] Air duct cloth is an important material for ventilation, exhaust and air delivery, and is widely used in tunnel construction, mining and underground engineering. In the processing of air duct cloth, double folding operation is one of the key steps. By folding and heat-sealing both sides of the air duct cloth, it can not only improve the strength and sealing performance of the product, but also avoid problems such as loose edges and falling off during use. However, the traditional double folding processing method of air duct cloth has many shortcomings, which brings great challenges to production efficiency and quality control.

[0003] In traditional processes, the double folding operation of the air duct cloth usually relies on a combination of a single folding device and manual adjustment. Specifically, it is necessary to fix one side of the air duct cloth and complete the folding, then manually readjust the position, and then fold the other side. This method requires manual intervention and adjustment after each folding, resulting in an intermittent and time-consuming production process, especially for large-sized air duct cloths, where the processing operation is more cumbersome. Summary of the invention

[0004] The purpose of the present invention is to provide a double folding mechanism for air duct cloth and a double folding method for air duct cloth in view of the problem that in the prior art, a single folding device is often used in combination with manual work to complete the double folding, resulting in low production efficiency of the air duct cloth.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A double folding mechanism for air duct cloth comprises a feeding device for conveying air duct cloth, the mechanism also comprises a transport frame, the transport frame comprises a horizontal transport frame and a vertical transport frame, the vertical transport frame is provided with a first folding device, the horizontal transport frame is provided with a second folding device, one end of the horizontal transport frame provided with the second folding device is connected to the vertical transport frame, the first folding device and the second folding device are arranged opposite to each other and are located at a diagonal position of the transport frame, the first folding device is located in the area above the second folding device; a conveying path is provided between the first folding device and the second folding device, and the conveying path is used to convey the air duct cloth.

[0007] The present invention is a double folding mechanism for air duct cloth. The mechanism realizes continuous transportation of air duct cloth and completes folding operations on both sides respectively through the combined design of vertical transport frame and horizontal transport frame, avoiding the problems of manual adjustment and repeated fixation in traditional processes, and greatly improving the processing efficiency; the design of the device fully considers the space utilization rate, and through the integrated folding and transportation functions, the equipment layout is more compact, which helps to reduce the floor space and is suitable for use in production workshops with limited space; the first folding device and the second folding device are arranged opposite to each other and are located at the diagonal position of the transport frame, so that the mechanism structure is compact and effectively saves the occupied space. At the same time, the first folding device is located in the upper area of ​​the second folding device, further improving the space utilization rate of the equipment; through the setting of the diagonal position, the first folding device and the second folding device can fold the diagonal edges of the air duct cloth respectively, avoiding the folding overlap or deformation problems that may be caused by the traditional same-side folding method, and ensuring the stability of the folding effect; the first folding device and the second folding device work together to complete the folding tasks of the two diagonal edges of the air duct cloth respectively, while simplifying the operation process, improving the overall processing efficiency and meeting the needs of mass production.

[0008] As a preferred embodiment of the present invention, the first folding device includes a first sleeve, a first mounting portion is provided on the first sleeve, a first connecting arm is sleeved on the first mounting portion, one end of the first connecting arm is sleeved with the first mounting portion, and the other end is sleeved with a first pressure roller.

[0009] The first connecting arm and the first mounting part can adjust the connection angle by means of socket connection, so that the pressure roller can adapt to air duct cloths of different thicknesses and materials, further improving the versatility and applicability of the device; the first sleeve and the first mounting part adopt a modular design, which is convenient for quick disassembly and replacement of components, reducing maintenance difficulty and downtime, and further improving production efficiency and equipment service life.

[0010] As a preferred solution of the present invention, a first mounting rod is provided on the vertical transport frame, and the first mounting rod is movably connected to the first folding device.

[0011] By sleeve-connecting the first folding device on the first mounting rod, the first folding device can be moved on the first mounting rod, so that the operator can adjust the width of the folding conveniently.

[0012] As a preferred embodiment of the present invention, a first heat sealer is provided on the vertical transport rack, the first heat sealer is movably connected to the first mounting rod, a first heat sealing point is provided on the first heat sealer, the first heat sealing point is located in the lower area of ​​the first folding device, and the first heat sealing point is arranged toward the air duct cloth on the vertical transport rack.

[0013] By arranging a first heat sealer on the first mounting rod, and the first heat sealing point on the first heat sealer is arranged toward the direction of the air duct cloth, when the air duct cloth is transported on the vertical transport rack, it is folded by the first folding device on the first mounting rod, and after folding, it is heat sealed by the first heat sealing point.

[0014] As a preferred embodiment of the present invention, the second folding device includes a second sleeve, a second mounting portion is provided on the second sleeve, a second connecting arm is sleeved on the second mounting portion, one end of the second connecting arm is connected to the second mounting portion, and the other end is sleeved with a second pressure roller.

[0015] The second connecting arm and the second mounting part adopt a socket or active connection design, which can be adjusted according to the thickness, material or width of the air duct cloth to meet the processing needs of air duct cloths of various specifications and improve the versatility of the equipment; the second sleeve and the second mounting part adopt a modular design, which is convenient for users to quickly disassemble, replace or adjust the components of the folding device, reduce downtime, and improve equipment maintenance efficiency and production continuity.

[0016] As a preferred solution of the present invention, a second mounting rod is provided on the horizontal transport frame, and the second mounting rod is movably connected to the second folding device.

[0017] By arranging the second folding device in a sleeve-connected form with the second mounting rod, an operator can control the width of the folded edge by moving the position of the second folding device on the second mounting rod.

[0018] As a preferred embodiment of the present invention, a second heat sealer is provided on the horizontal transport rack, the second heat sealer is arranged in the downstream direction of the second folding device, a second heat sealing point is provided on the second heat sealer, and the second heat sealing point is arranged toward the air duct cloth transported on the horizontal transport rack.

[0019] The second heat sealer is arranged in the downstream direction of the second folding device. It can heat seal the air duct cloth through the second heat sealing point immediately after the air duct cloth completes the horizontal folding. No additional procedures and equipment are required, thereby achieving efficient linkage between folding and heat sealing, simplifying the production process and improving processing efficiency.

[0020] As a preferred solution of the present invention, a roller mechanism is provided at one end of the horizontal transport frame away from the feeding device, and the roller mechanism is used to transport the air duct cloth.

[0021] The roller mechanism is arranged at one end of the horizontal transport frame away from the feeding device. It can efficiently and smoothly transport the air duct cloth to the next process or designated area after heat sealing is completed, reducing the residence time and manual handling links, and greatly improving the overall transportation efficiency.

[0022] As a preferred embodiment of the present invention, the feeding device includes a first transport device and a second transport device, the first transport device and the second transport device are used for air duct cloths of different sizes; the first transport device and the second transport device are staggered.

[0023] The automated size-based conveying design reduces the manual work of sorting and placing the air duct cloths, reduces labor intensity, and reduces conveying errors or delays caused by human operations, thus improving the overall automation level.

[0024] A double-folding method for a duct cloth, the method adopts the above-mentioned double-folding mechanism for duct cloth to perform folding, and the method comprises:

[0025] S1, the feeding device transports the air duct cloth to the vertical transport rack;

[0026] S2, the vertical transport rack transports the air duct cloth to the horizontal transport rack through the transport path;

[0027] S21, when the air duct cloth is conveyed to the horizontal transport rack through the conveying path, the air duct cloth is folded and heat-sealed by the first folding device and the first heat sealer; after the air duct cloth is conveyed to the horizontal transport rack, the air duct cloth is folded and heat-sealed again by the second folding device and the second heat sealer;

[0028] S3, complete the double folding operation.

[0029] The present invention discloses a double folding method for air duct cloth. The method adopts the cooperation of double transport frames and double folding devices, and can realize the fully automatic processing flow of vertical folding on one side and horizontal folding on the other side of the air duct cloth, reduce manual intervention, and greatly improve production efficiency and folding accuracy. The method combines the staggered design of the first transport device and the second transport device, and can process large-sized and small-sized air duct cloths at the same time, meet the production requirements of products of different specifications, and improve the applicability of the equipment.

[0030] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0031] 1. The present invention is a double folding mechanism for air duct cloth. This mechanism realizes continuous transportation of air duct cloth and completes the folding operation on both sides respectively through the combined design of vertical transport frame and horizontal transport frame, avoiding the problems of manual adjustment and repeated fixation in traditional processes, and greatly improving the processing efficiency; the design of this device fully considers the space utilization rate, and through the integrated folding and transportation functions, the equipment layout is more compact, which helps to reduce the floor space and is suitable for use in production workshops with limited space; the first folding device and the second folding device are arranged opposite to each other and are located at the diagonal position of the transport frame, so that the mechanism structure is compact and effectively saves the occupied space. At the same time, the first folding device is located in the upper area of ​​the second folding device, which further improves the space utilization rate of the equipment; through the setting of the diagonal position, the first folding device and the second folding device can fold the diagonal edges of the air duct cloth respectively, avoiding the folding overlap or deformation problem that may be caused by the traditional same-side folding method, and ensuring the stability of the folding effect; the first folding device and the second folding device work together to complete the folding tasks of the two diagonal edges of the air duct cloth respectively, while simplifying the operation process, improving the overall processing efficiency and meeting the needs of mass production.

[0032] 2. The present invention is a double folding method for air duct cloth. The method adopts the cooperation of double transport frames and double folding devices, which can realize the fully automatic processing flow of vertical folding on one side of the air duct cloth and horizontal folding on the other side, reduce manual intervention, and greatly improve production efficiency and folding accuracy; the method combines the staggered design of the first transport device and the second transport device, which can process large-sized and small-sized air duct cloths at the same time, meet the production needs of products of different specifications, and improve the applicability of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the transport frame of the present invention;

[0034] Figure 2 It is a schematic diagram of the folding steps of the present invention;

[0035] Figure 3 It is a structural schematic diagram of the double-folding mechanism of the air duct cloth of the present invention;

[0036] Figure 4 The present invention Figure 3 A magnified image of point A;

[0037] Figure 5 The present invention Figure 3 The enlarged view of point B;

[0038] Figure 6 is a schematic structural diagram of a second folding device of the present invention;

[0039] Figure 7 is a schematic structural diagram of a first folding device of the present invention;

[0040] Figure 8 It is a flow chart of the double hemming method of the present invention.

[0041] Icons: 1-feeding device; 11-first transport device; 12-second transport device; 2-transport frame; 21-horizontal transport frame; 211-second folding device; 2111-second sleeve; 2112-second mounting portion; 2113-second connecting arm; 21131-second connecting rod; 21132-second sleeve; 2114-second pressure roller; 22-vertical transport frame; 212-second mounting rod; 213-second heat sealer; 2131-second heat sealing point; 221-first folding device; 2211-first sleeve; 2212-first mounting portion; 2213-first connecting arm; 22131-first connecting rod; 22132-first sleeve; 2214-first pressure roller; 222-first mounting rod; 223-first heat sealer; 2231-first heat sealing point; 23-roller mechanism. DETAILED DESCRIPTION

[0042] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0043] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are based on the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments to facilitate the technicians to quickly understand the scheme, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation of the present invention.

[0044] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.

[0045] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.

[0046] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.

[0047] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.

[0048] Example 1

[0049] like Figures 1 to 5A double folding mechanism for air duct cloth is shown, the mechanism comprises a feeding device 1 for conveying air duct cloth, the feeding device comprises a first conveying device 11 for conveying large-sized air duct cloth and a second conveying device 12 for conveying small-sized air duct cloth; the mechanism also comprises a transport frame 2 for receiving the air duct cloth conveyed by the feeding device 1 and processing it, the transport frame 2 comprises a vertical transport frame 22 and a horizontal transport frame 21, the vertical transport frame 22 is provided with a first folding device 221 and a first heat sealer 223, after the feeding device 1 conveys the air duct cloth to the transport frame 2, the air duct cloth first passes through the vertical transport frame 22, and one side of the air duct cloth is folded by the first folding device 221 arranged on one side of the vertical transport frame 22, and the folded edge is heat-sealed by the first heat sealer 223 during the folding process, thereby realizing the first folding of the air duct cloth;

[0050] After the air duct cloth has completed the first folding through the vertical transport rack 22, it is transported to the horizontal transport rack 21. The horizontal transport rack 21 is provided with a second folding device 211, and a second heat sealer 213 is provided downstream of the second folding device 211. The air duct cloth passes through the second folding device 211 and performs a second folding on the side of the air duct cloth that has not been folded, and completes the heat sealing through the second heat sealer 213, thereby realizing double folding of the air duct cloth.

[0051] In one or more embodiments, a first mounting rod 222 is provided on the vertical transport frame 22, and a first folding device 221 and a first heat sealer 223 are sleeved on the first mounting rod 222. By sleeve-fitting the first folding device 221 on the first mounting rod 222, the first folding device 221 can be moved on the first mounting rod 222, so that the operator can adjust the width of the folded edge conveniently;

[0052] Furthermore, the horizontal transport frame 21 is provided with a second mounting rod 212, and the second mounting rod 212 is sleeved with a second folding device 211, such as Figure 4 to Figure 5 shown.

[0053] In one or more embodiments, the first folding device 221 includes a first sleeve 2211, the first sleeve 2211 is sleeved on the outer arm of the first mounting rod 222, and the first sleeve 2211 is provided with a first mounting portion 2212, the first mounting portion 2212 is sleeved with a first connecting arm 2213, the first connecting arm 2213 includes a first connecting rod 22131, both ends of the first connecting rod 22131 are provided with a first sleeve 22132, the first connecting arm 2213 is connected through two The first sleeve 22132 is connected to the first mounting portion 2212 and the first pressure roller 2214. The first connecting arm 2213 and the first mounting portion 2212 can adjust the connection angle by sleeve connection, so that the first pressure roller 2214 can adapt to the wind tube cloths of different thicknesses and materials, further improving the versatility and applicability of the device; the first sleeve 2211 and the first mounting portion 2212 adopt a modular design, which is convenient for quick disassembly and replacement of components, reducing the difficulty of maintenance and downtime, and further improving production efficiency and service life of the equipment. Figure 7 shown.

[0054] In one or more embodiments, the second folding device 211 includes a second sleeve 2111, the second sleeve 2111, the second sleeve 2111 is sleeved on the outer wall of the second mounting rod 212, and the second sleeve 2111 is provided with a second mounting portion 2112, the second mounting portion 2112 is sleeved with a second connecting arm 2113, the second connecting arm 2113 includes a second connecting rod 21131, and both ends of the second connecting rod 21131 are provided with second sleeves 21132, and the second connecting arm 2113 is connected by two The second sleeve 21132 is connected to the second mounting portion 2112 and the second pressure roller 2114. The second connecting arm 2113 and the second mounting portion 2112 can adjust the connection angle by sleeve connection, so that the second pressure roller 2114 can adapt to the wind tube cloths of different thicknesses and materials, further improving the versatility and applicability of the device; the second sleeve 2111 and the second mounting portion 2112 adopt a modular design, which is convenient for quick disassembly and replacement of components, reducing the difficulty of maintenance and downtime, and further improving production efficiency and service life of the equipment. Figure 6 shown.

[0055] In one or more embodiments, a roller mechanism 23 is provided at one end of the horizontal transport frame 21 away from the feeding device 1. The roller mechanism 23 is used to transport the heat-sealed air-tight cloth. The roller mechanism 23 is arranged at one end of the horizontal transport frame 21 away from the feeding device 1, and can efficiently and smoothly transport the air-tight cloth to the next process or designated area after heat sealing, thereby reducing the residence time and manual handling links, and greatly improving the overall transportation efficiency. Figure 2 shown.

[0056] In one or more embodiments, the feeding device 1 includes a first transport device 11 and a second transport device 12, wherein the first transport device 11 is used to transport large-sized wind tube cloths, and the second transport device 12 is used to transport small-sized wind tube cloths; the first transport device 11 and the second transport device 12 are staggered, such as Figure 2 shown.

[0057] Example 2

[0058] like Figure 8 A double folding method for a duct cloth is shown, and the method adopts a double folding mechanism for a duct cloth in Example 1 to perform folding, and the method comprises:

[0059] S1, the feeding device 1 is started to transport the air duct cloth to the top of the vertical transport rack 22;

[0060] S2, the vertical transport rack 22 transports the air duct cloth from the top through the transport path to the horizontal transport rack 21;

[0061] S21, when the air duct cloth passes through the first folding device 221 in the conveying path, the first folding device 221 folds the edge close to the vertical transport frame 22, and the folded air duct cloth continues to pass through the first heat sealer 223, and the heat sealing point of the first heat sealer 223 acts on the folding area to heat seal the folded edge of the air duct cloth, and the air duct cloth reaches the horizontal transport frame 21 and verifies that the horizontal transport frame 21 continues to transport, when the air duct cloth passes through the second folding device 211, since the second folding device 211 is diagonally arranged with the first folding device 221, the second folding device 211 folds the edge on the other side of the air duct cloth, and then passes through the second heat sealer 213, and the folded edge is heat sealed by the second heat sealer 213;

[0062] S3, complete the double folding.

[0063] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A double-folding mechanism for a duct cloth, comprising a feeding device (1) for conveying duct cloth, characterized in that: The mechanism also includes a transport frame (2), the transport frame (2) including a horizontal transport frame (21) and a vertical transport frame (22), the vertical transport frame (22) being provided with a first folding device (221), the horizontal transport frame (21) being provided with a second folding device (211), one end of the horizontal transport frame (21) provided with the second folding device (211) being connected to the vertical transport frame (22), the first folding device (221) and the second folding device (211) being arranged opposite to each other and being located at a diagonal position of the transport frame (2), the first folding device (221) being located in an area above the second folding device (211); a conveying path being provided between the first folding device (221) and the second folding device (211), the conveying path being used for conveying the wind tube cloth.

2. A double folding mechanism for a hair dryer cloth according to claim 1, characterized in that: The first folding device (221) comprises a first sleeve (2211), the first sleeve (2211) is provided with a first mounting portion (2212), the first mounting portion (2212) is sleeved with a first connecting arm (2213), one end of the first connecting arm (2213) is sleeved with the first mounting portion (2212), and the other end is sleeved with a first pressing roller (2214).

3. A double folding mechanism for a hair dryer cloth according to claim 2, characterized in that: The vertical transport frame (22) is provided with a first mounting rod (222), and the first mounting rod (222) is movably connected to the first folding device (221).

4. A double-folding mechanism for a wind tube cloth according to claim 3, characterized in that: The vertical transport frame (22) is provided with a first heat sealer (223), the first heat sealer (223) is movably connected to the first mounting rod (222), a first heat sealing point (2231) is arranged on the first heat sealer (223), the first heat sealing point (2231) is located in the lower area of ​​the first folding device (221), and the first heat sealing point (2231) is arranged toward the air duct cloth on the vertical transport frame (22).

5. A double-folding mechanism for a wind tube cloth according to claim 4, characterized in that: The second folding device (211) comprises a second sleeve (2111), the second sleeve (2111) is provided with a second mounting portion (2112), the second mounting portion (2112) is sleeved with a second connecting arm (2113), one end of the second connecting arm (2113) is connected to the second mounting portion (2112), and the other end is sleeved with a second pressing roller (2114).

6. A double-folding mechanism for a hair dryer cloth according to claim 5, characterized in that: The horizontal transport frame (21) is provided with a second mounting rod (212), and the second mounting rod (212) is movably connected to the second folding device (211).

7. A double-folding mechanism for a wind tube cloth according to claim 6, characterized in that: A second heat sealer (213) is provided on the horizontal transport rack (21), and the second heat sealer (213) is arranged in the downstream direction of the second folding device (211). A second heat sealing point (2131) is provided on the second heat sealer (213), and the second heat sealing point (2131) is arranged toward the air duct cloth transported on the horizontal transport rack (21).

8. A double-folding mechanism for a wind tube cloth according to any one of claims 1 to 7, characterized in that: A roller mechanism (23) is provided at one end of the horizontal transport frame (21) away from the feeding device (1), and the roller mechanism (23) is used for transporting the air duct cloth.

9. A double-folding mechanism for a hair dryer cloth according to claim 8, characterized in that: The feeding device (1) comprises a first transport device (11) and a second transport device (12); the first transport device (11) and the second transport device (12) are used for air duct cloths of different sizes; the first transport device (11) and the second transport device (12) are staggered.

10. A method for double folding an air duct cloth, characterized in that: The double folding mechanism for the air duct cloth according to any one of claims 1 to 9 is used for folding, comprising: S1, the feeding device (1) transports the air duct cloth to the vertical transport rack (22); S2, the vertical transport frame (22) transports the air duct cloth to the horizontal transport frame (21) through the transport path; S21, when the air duct cloth is being conveyed to the horizontal conveying frame (21) through the conveying path, the air duct cloth is folded and heat-sealed by the first folding device (221) and the first heat sealer (223); after the air duct cloth is conveyed to the horizontal conveying frame (21), it is folded and heat-sealed again by the second folding device (211) and the second heat sealer (213); S3, complete the double folding operation.

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