A continuous production process for impregnated sponge

Abstract

The present invention provides a continuous production process for dipped sponges, belonging to the technical field of sponge production. It includes a dipping and degumming material guiding mechanism and a heating and curing mechanism. The dipping and degumming material guiding mechanism includes a material guiding tower, a first clamping belt and a second clamping belt. The first clamping belt and the second clamping belt are both flexible mesh belt structures connected end to end. A plurality of common guide wheels are provided in the material guiding tower. The first clamping belt and the second clamping belt both pass through the common guide wheels. The first clamping belt and the second clamping belt can sequentially pass the sponge to be dipped in a clamped state through the feed port, the glue storage chamber, the degumming chamber and the discharge port. The sponge to be dipped is fed into the feed port, and the sponge is pulled forward for a distance and then moved in the reverse direction for a distance. During a single action, the distance of forward movement is greater than the distance of reverse movement, so as to ensure that the sponge as a whole is in a state of moving from the feed port to the discharge port; the sponge in the heating and curing stage is in a reciprocating motion state while maintaining an overall forward movement. The present invention has the advantages of high efficiency and good product quality.

Description

Technical Field

[0001] The invention belongs to the technical field of sponge production and relates to a continuous production process of a dipped sponge. Background Art

[0002] Negative pressure drainage sponges are primarily used in negative pressure closed drainage technology, which primarily utilizes a biological semipermeable membrane to seal open wounds. A dedicated negative pressure machine generates a certain amount of negative pressure, which is then applied to the cleansed wound surface via a drainage tube and porous sponge. This therapy can accelerate blood circulation within the wound, significantly promote the entry of new blood vessels into the wound, stimulate the growth of granulation tissue, provide adequate drainage, reduce edema, minimize contamination, and inhibit bacterial growth, directly accelerating wound healing. It is an efficient, simple, and economical purely physical therapy for promoting wound healing.

[0003] However, the sponge material used in negative pressure drainage technology must have good fluid conduction properties to remove pus and tissue fluid from the wound; at the same time, the sponge is in direct contact with the wound, and its soft texture is also an important aspect of the negative pressure drainage sponge; in the actual application of the negative pressure drainage sponge, due to the long material replacement cycle, the new granulation tissue can easily adhere to and entangle with the porous polyurethane sponge fibers during long-term contact with the wound, thereby causing damage to the new granulation tissue during the sponge replacement process, greatly reducing the wound healing time.

[0004] The dipping sponge can greatly improve the flexibility of the sponge. It is achieved by attaching a silicone layer to the sponge wire diameter. It can also prevent the new granulation tissue from being entangled during the long-term contact between the sponge wire diameter and the wound. However, the conventional dipping method is: first soak the sponge in the glue, then take it out and squeeze out the excess glue, and wait for the glue to solidify on the sponge to complete the preparation of the dipped sponge. However, the dipped sponge produced according to this dipping process has the following defects: 1. The coverage of the glue on the sponge wire diameter is not uniform, because the glue will settle during the solidification process, so that the amount of glue attached to the thickness direction of the sponge gradually increases from top to bottom, which affects the uniformity of the sponge pore size and may even cause the lower sponge pores to be blocked by the glue; 2. In the process of squeezing out the excess glue, the sponge is subjected to a strong external physical force. Part of the wire diameter will break, destroying part of the pore structure and easily generating wire debris. These debris may fall off during the use of the dipped sponge, affecting the cleanliness of the wound or remaining in the new skin and flesh tissue; 3. It is difficult to achieve continuous production. On the one hand, the sponge has good tensile properties, and the traction process is likely to cause tensile damage to the sponge. On the other hand, the degree of tensile deformation is inconsistent, which will affect the amount of adhesive, curing time and product uniformity within the established process time; 4. The curing time of silicone on the sponge requires about 5 minutes in an environment of about 130 degrees Celsius, which seriously restricts the production efficiency of continuous production. Summary of the Invention

[0005] The purpose of the present invention is to provide a continuous production process for dipped sponge in view of the above-mentioned problems existing in the existing technology. The technical problem to be solved by the present invention is how to improve the quality and production efficiency of dipped sponge.

[0006] The object of the present invention can be achieved through the following technical solutions: A continuous production process of dipped sponge, characterized in that continuous production is carried out on a dipped sponge production line, the dipped sponge production line includes a dipping and degumming material guiding mechanism and a heating and curing mechanism, the dipping and degumming material guiding mechanism includes a material guiding tower, a first clamping belt and a second clamping belt, the material guiding tower includes a material inlet, a material outlet, a glue storage cavity and a degumming cavity, the first clamping belt and the second clamping belt are both flexible mesh belt structures connected end to end, a plurality of common guide wheels are arranged in the material guiding tower, the first clamping belt passes through a plurality of first guide wheels and each common guide wheel located outside the material guiding cylinder, and the second clamping belt passes through a plurality of second guide wheels and each common guide wheel located outside the material guiding cylinder;

[0007] The first clamping belt and the second clamping belt can sequentially pass the sponge to be dipped in glue through the feed port, glue storage cavity, degumming cavity and discharge port in a clamping state;

[0008] The heating and curing mechanism includes a heating box, and the material discharged from the discharge port is pulled through the heating box;

[0009] The production process comprises the following steps:

[0010] S1, feeding the sponge to be dipped into the material inlet so that the sponge to be dipped into the material inlet is clamped between the first clamping belt and the second clamping belt;

[0011] S2. Control the synchronous jogging of the first entrainment belt and the second entrainment belt; the jogging rule of the first entrainment belt and the second entrainment belt is: the sponge is pulled forward for a distance and then moved in the reverse direction for a distance. During a single action, the forward movement distance is greater than the reverse movement distance to ensure that the sponge as a whole is in a state of moving from the feed port to the discharge port; during the heating and curing stage, the sponge is in a reciprocating motion state while maintaining an overall forward movement.

[0012] Furthermore, a filter screen is provided between the bottom of the degumming chamber and the glue storage chamber.

[0013] Furthermore, the first clamping belt and the second clamping belt are respectively provided with a first tensioning wheel and a second tensioning wheel to keep each in a tensioned state.

[0014] Furthermore, the heating box includes a collecting cover and several air supply pipes located at the lower opening of the collecting cover. Heaters are provided in the air supply pipes. The air supply pipes are connected in parallel and connected to the air outlet end of a blower.

[0015] Furthermore, a carrier belt is provided at the lower opening of the collecting cover, and the carrier belt is pulled by a plurality of guide wheels. The carrier belt is a flexible structure connected end to end, and the carrier belt forms a plurality of concave sections corresponding to each air supply pipe at the lower opening of the collecting cover, and there is a straight section between adjacent concave sections, and the sponge to be solidified is supported by the straight section; the running state of the carrier belt is consistent with the running state of the first entrainment belt.

[0016] Compared with the existing dipping method, this solution has the following characteristics and advantages:

[0017] 1. The sponge is clamped by the first clamping belt and the second clamping belt during the dipping and degumming process, so that the sponge is not subjected to tensile force during the traction process, thus avoiding sponge damage and the retention of network bubble residues;

[0018] 2. Due to the use of the first and second clamping belts to clamp the sponge, the deformation properties of the sponge do not need to be considered during the traction process. A relatively intense traction method can be used, such as inching traction, combined with a wavy running trajectory, so that the sponge is in an intermittent "shaking" state in the degumming cavity. The highly fluid silicone liquid can be separated from the sponge during the shaking process. Compared with the traditional extrusion degumming method, the sponge has a smaller degree of deformation, the glue flow frequency on the sponge wire diameter is greater, and the degumming is more uniform, which can better protect the sponge from damage and improve the uniformity of the dipped sponge product. Thicker sponges can also achieve better dipping and degumming.

[0019] 3. The first and second entrainment in the shaking state can prevent the sponge from being thoroughly soaked when it passes through the glue storage chamber continuously. The intermittent movement of the sponge and the agitated inertia of the glue liquid can make the contact between the glue liquid and the sponge more complete and soak it completely.

[0020] 4. During the curing stage after the sponge is dipped in glue, intermittent upward blowing of hot air is used to heat the sponge intermittently, and the upward airflow is used to offset the sedimentation of the uncured glue attached to the sponge. Since the curing time takes 3-8 minutes, if anti-settling measures are not taken, the glue on the sponge wire will flow downward under the weight, which will inevitably cause the silicone adhesion thickness of the lower sponge to be greater than the silicone adhesion thickness of the upper sponge, resulting in poor uniformity of the silicone sponge product after cutting into blocks, and even causing the pores in the lower part of the sponge to be clogged;

[0021] 5. Indirect traction is adopted in the stages of dipping, degumming, heating and curing to avoid direct pulling of the sponge during the traction process, thereby increasing the traction speed and improving the continuous processing efficiency without damaging the sponge;

[0022] 6. In this solution, the requirements for the shape of the sponge raw materials used to process the dipped sponge are relatively low. Sheets, rolls, sponge fragments of different sizes, and sponge fragments of different thicknesses within a certain range can all be continuously dipped online through this production line. They can be fed from the feed port. The sponge does not have to be in a roll to be able to operate continuously.

[0023] 7. This solution uses a carrier belt, a first entrainment belt, and a second entrainment belt to prevent the sponge from directly contacting the transmission components before curing. This is because liquid silicone will cure even at room temperature, but the curing time is long. If the sponge is in direct contact with the transmission components, the semi-dry (low-fluidity) silicone adhered to the transmission components will adhere to the sponge, causing the sponge to tear. In this solution, the first and second entrainment belts circulate, and part of them are located outside the material guide tower. The first and second entrainment belts can be cleaned online without stopping the machine. Similarly, the carrier belt can also be cleaned online, which greatly reduces maintenance costs and allows continuous production without stopping during the room-temperature curing time of the silicone, thereby improving production efficiency.

[0024] 8. During the process of dipping and heating curing, the sponge is in a reciprocating motion state, which can greatly shorten the length of the curing heating section and extend the heating time. In addition, the sponge can be spun for a longer time and more times, which can improve the uniformity of the glue adhesion on the sponge. The length and occupied space of the entire production line can be greatly reduced, and the efficiency can be improved and the cost can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the principle of this dipped sponge production line.

[0026] Figure 2 It is a structural diagram of a material guide tower for dipping and degumming.

[0027] Figure 3 It is a schematic diagram of the structure of a heating box for heating and curing.

[0028] Figure 4 Schematic diagram of the porous structure of the first entrainment and the second entrainment.

[0029] In the figure, 11, first clamping belt; 12, second clamping belt; 21, feed port; 22, discharge port; 23, glue storage chamber; 24, degumming chamber; 25, common guide wheel; 26, first guide wheel; 27, second guide wheel; 28, filter; 31, tensioning wheel one; 32, tensioning wheel two; 41, collecting cover; 42, air supply pipe; 43, heater; 44, carrier belt; 45, guide wheel three; 46, concave section. DETAILED DESCRIPTION

[0030] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0031] like Figure 1 As shown, a number of common guide wheels 25 are provided in the material guide tower. The common guide wheels 25 located in the glue storage chamber 23 allow the sponge to fully contact the glue in the glue storage chamber 23. The common guide wheels 25 located in the degumming chamber 24 are regularly distributed. Generally speaking, the common guide wheels 25 located in the degumming chamber 24 are divided into two longitudinal rows, and the two transverse common guide wheels 25 are staggered, so that the sponge can ascend in a reciprocating state in the traction path in the degumming chamber 24. Both sides of the first entrainment belt 11 and the second entrainment belt 12 have a certain height of retaining edge, so that the sponge is limited by the first entrainment belt 11 and the second entrainment belt 12, avoiding the sponge from contacting other transmission components except the first entrainment belt 11 and the second entrainment belt 12, thereby preventing the glue adhering to other transmission components from adhering to the sponge and damaging the sponge. The first entrainment belt 11 and the second entrainment belt 12 can pass the sponge to be dipped in glue through the feed port 21, the glue storage chamber 23, the degumming chamber 24 and the discharge port 22 in a clamped state.

[0032] The first entrainment belt 11 and the second entrainment belt 12 are respectively provided with a tensioning wheel 1 31 and a tensioning wheel 2 32 to keep them in a tensioned state, ensuring that the first entrainment belt 11 and the second entrainment belt 12 have a certain tensioning force. Sponges of different thicknesses can still be effectively clamped after being fed at the feeding port 21. Even if there may be a gap between part of the first entrainment belt 11 and the second entrainment belt 12 after the block sponge is fed, normal operation can still be achieved.

[0033] The heating box includes a collecting cover 41 and several air supply pipes 42 located at the lower opening of the collecting cover 41. A heater 43 is provided in the air supply pipes 42. After being connected in parallel, each air supply pipe 42 is connected to the air outlet end of a blower. The sponge between the discharge port 22 of the material guide tower and the collecting cover 41 can be in a relaxed state to avoid pulling the sponge at the connection position; the air supply pipe 42 is flat and intermittently supplies air to the moving sponge for heating and curing. The hot air passes through the sponge and is discharged from the top of the collecting cover 41.

[0034] A carrier belt 44 is installed at the lower opening of the hood 41. This belt 44 is pulled by several guide wheels 45. The carrier belt 44 is a flexible structure connected end to end. Several concave sections 46 are formed at the lower opening of the hood 41, corresponding to each air supply tube 42. A straight section is located between adjacent concave sections 46, supporting the sponge to be cured. This method not only effectively prevents the glue from settling during heating, but also prevents the carrier belt 44 from constantly contacting the sponge, thereby preventing the sponge from adhering to the carrier belt 44. A larger number of air supply tubes 42 can be installed to enhance this characteristic. The carrier plate should be made of metal whenever possible, as metal has poor adhesion to silicone and should not be heated to very high temperatures.

[0035] The liquid silicone used for dipping has a viscosity of 1300mPa·S / ℃-13000mPa·S / ℃, cures in 7-9 hours at room temperature, and is fully cured in 200s-400s at 130℃-160℃. After being heated at around 80℃ for about 5 minutes, the silicone liquid basically loses its fluidity on the sponge wire diameter, and then is naturally cooled online until it is completely cured. After the liquid silicone is cured on the non-dipped sponge, the hardness is 5-20 Shore A to ensure that the dipped sponge does not cause obvious tingling to the patient's wound when used on the wound.

[0036] A polyester / polyether polyurethane sponge with a diameter of 30-55ppi is selected and exploded in a web-exploding machine to obtain a polyurethane web. The thickness of the cured silicone coating on the sponge wire diameter is between 20um and 50um. The liquid silicone is a mixture of base glue, vinyl-terminated silicone oil, polysiloxane containing silicon hydrogen groups in the side chain, a catalyst and an inhibitor, and is obtained by a silicon hydrogen addition reaction.

[0037] like Figure 1 、 Figure 2 and Figure 4 As shown, the sponge is clamped by the first clamping belt 11 and the second clamping belt 12 during the process of dipping and degumming. The first clamping belt 11 and the second clamping belt 12 are flexible belts with a porous structure of a wire mesh. They can be made of metal without deformation ability, or can be a colloid material with certain tensile properties. The purpose is to put the sponge in an indirect traction state to avoid the sponge being subjected to a large tensile force during the traction process, thereby avoiding sponge damage and the retention of pore residues. The sponge is prone to residues in the pores after being injured. When used for negative pressure drainage, these residues may remain in the new flesh teeth, seriously affecting the safety of the product.

[0038] Since the sponge is clamped by the first entrainment belt 11 and the second entrainment belt 12, during the traction process, the deformation properties of the sponge do not need to be considered, and a relatively intense traction method can be used, such as inching traction. The so-called inching traction is to control the intermittent rotation of a first guide wheel 26 and a second guide wheel 27 by a stepping motor respectively, and even a reciprocating rotation method can be used, such as a single forward drive to move the sponge for a distance, and then reverse drive to move the sponge for a distance, but it is necessary to ensure that the single reverse movement distance is less than the forward movement distance, and ensure that the sponge is in a forward state as a whole, in coordination with the wave The shaped running trajectory makes the sponge in the degumming chamber 24 in an intermittent "shaking" state. The silicone liquid with higher fluidity can be separated from the sponge during the shaking process. After the remaining silicone liquid is shaken off the sponge, it enters the glue storage chamber 23 through the filter screen 28 for reuse. Compared with the traditional extrusion degumming method, the sponge has a smaller degree of deformation, a higher frequency of flow of the glue on the sponge wire diameter, and a more uniform degumming. The sponge does not need to be rigidly squeezed to remove the remaining glue, which can better protect the sponge and improve the uniformity of the dipped sponge product. Thicker sponges can also achieve better dipping and degumming.

[0039] The first and second entrainment belts 11 and 12 in a shaking state can avoid incomplete immersion of the sponge that passes continuously through the glue storage chamber 23. They use the intermittent movement of the sponge and the agitated inertia of the glue to make the contact between the glue and the sponge more complete and the immersion complete, thereby shortening the dipping time.

[0040] like Figure 3 As shown in the figure, during the curing stage after the sponge is dipped in glue, intermittent upward blowing of hot air is used to heat the sponge intermittently, and the upward airflow is used to offset the sedimentation of the uncured glue attached to the sponge. Since the curing time takes 3-8 minutes, if anti-settling measures are not taken, the glue on the sponge wire will flow downward under the weight, which will inevitably cause the silicone adhesive thickness of the lower sponge to be greater than the silicone adhesive thickness of the upper sponge, resulting in poor uniformity of the silicone sponge product after cutting into blocks, and even causing the pores in the lower part of the sponge to be clogged.

[0041] Since indirect traction is adopted in the stages of dipping, degumming, heating and curing, the sponge is prevented from being directly pulled during the traction process, thereby increasing the traction speed and improving the continuous processing efficiency without damaging the sponge;

[0042] In this solution, the requirements for the shape of the sponge raw material used to process the dipped sponge are relatively low. Sponge fragments in sheet form, roll form, different sizes, and different thicknesses within a certain range can all be continuously dipped online through this production line and can be fed from the feed port 21. It is not required that the sponge must be in a roll form to be able to operate continuously.

[0043] This solution uses the carrier belt 44, the first entrainment belt 11 and the second entrainment belt 12 to prevent the sponge from directly contacting the transmission components before solidification. This is because liquid silicone will solidify even at room temperature, but the solidification time is relatively long. If the sponge is in direct contact with the transmission components, the semi-dry silicone with low fluidity adhered to the transmission components will adhere to the sponge, causing the sponge to be torn; in this solution, the first entrainment belt 11 and the second entrainment belt 12 circulate and are partially located outside the material guide tower. The first entrainment belt 11 and the second entrainment belt 12 can be cleaned online without stopping the machine. Similarly, the carrier belt 44 can also be cleaned online, which greatly reduces maintenance costs and allows continuous production without stopping during the room temperature curing time of the silicone, thereby improving production efficiency.

[0044] In the idle sections of the first entrainment belt 11, the second entrainment belt 12, and the carrier belt 44, devices for cleaning them can be respectively provided, such as heat scraping, etc., to clean the silicone adhered to their surfaces. The silicone in the glue storage cavity 23 is added continuously, and is supplied while being mixed according to the raw material ratio, so as to extend its room temperature curing time, ensuring that the glue storage cavity 23 and the filter screen 28 do not need to be cleaned within an operating cycle of about 12 hours. After an operating cycle, the glue storage cavity 23 needs to be cleaned, and each transmission part can be cleaned after multiple operating cycles. There is no need to disassemble the material guide tower and the heating box for cleaning. It is only necessary to apply the cleaning agent to the first entrainment belt 11, the second entrainment belt 12, and the carrier belt 44 without introducing the sponge, and each transmission part can be cleaned during operation.

[0045] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A continuous production process for dipped sponge, characterized in that: Continuous production is carried out on a dipping sponge production line, which includes a dipping and degumming material guiding mechanism and a heating and curing mechanism. The dipping and degumming material guiding mechanism includes a guiding tower, a first entraining belt (11) and a second entraining belt (12). The guiding tower includes a material inlet (21), a material outlet (22), a glue storage cavity (23) and a degumming cavity (24). The first entraining belt (11) and the second entraining belt (12) are both flexible mesh belt structures connected end to end. A plurality of common guide wheels (25) are provided in the guiding tower. The first entraining belt (11) passes through a plurality of first guide wheels (26) and each common guide wheel (25) located outside the guiding tower, and the second entraining belt (12) passes through a plurality of second guide wheels (27) and each common guide wheel (25) located outside the guiding tower. The first clamping belt (11) and the second clamping belt (12) can sequentially pass the sponge to be dipped in glue through the feed port (21), the glue storage cavity (23), the degumming cavity (24) and the discharge port (22) in a clamped state; The heating and curing mechanism comprises a heating box, and the impregnated sponge coming out of the discharge port (22) is pulled through the heating box; The production process comprises the following steps: S1, feeding the sponge to be dipped into the material inlet, so that the sponge to be dipped into the material inlet is clamped between the first clamping belt (11) and the second clamping belt (12); S2, controlling the synchronous jogging of the first entrainment belt (11) and the second entrainment belt (12); the jogging rule of the first entrainment belt (11) and the second entrainment belt (12) is: the sponge is pulled forward for a distance and then moved in the reverse direction for a distance, and the distance of the forward movement during a single action is greater than the distance of the reverse movement, so as to ensure that the sponge as a whole is in a state of moving from the feed port to the discharge port; the sponge in the heating and curing stage is in a reciprocating motion state while maintaining the overall forward movement.

2. A continuous production process for dipped sponge according to claim 1, characterized in that: The traction paths of the first entraining belt (11) and the second entraining belt (12) in the degumming chamber (24) are wavy, and the first entraining belt (11) and the second entraining belt (12) are synchronously moved.

3. A continuous production process for dipped sponge according to claim 1, characterized in that: A filter screen (28) is provided between the bottom of the degumming chamber (24) and the glue storage chamber (23).

4. The continuous production process of a dipped sponge according to claim 1, characterized in that: The first clamping belt (11) and the second clamping belt (12) are respectively provided with a tensioning wheel 1 (31) and a tensioning wheel 2 (32) for placing each of them in a tensioned state.

5. A continuous production process for dipped sponge according to any one of claims 1 to 4, characterized in that: The heating box comprises a collecting cover (41) and a plurality of air supply pipes (42) located at the lower opening of the collecting cover (41). A heater (43) is provided in each of the air supply pipes (42). The air supply pipes (42) are connected in parallel and communicated with the air outlet end of a blower.

6. A continuous production process for dipped sponge according to claim 5, characterized in that: A carrier belt (44) is provided at the lower opening of the collecting cover (41), and the carrier belt (44) is pulled by a plurality of guide wheels (45). The carrier belt (44) is a flexible structure connected end to end. The carrier belt (44) forms a plurality of concave sections (46) corresponding to the air supply pipes (42) at the lower opening of the collecting cover (41), and a straight section is provided between adjacent concave sections (46). The sponge to be solidified is supported by the straight section. The running state of the carrier belt (44) is kept synchronous with the running state of the first entrainment belt (11).

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