CN113799202B - Method for improving online cutting precision of sponge - Google Patents

Abstract

The invention provides a method for improving sponge on-line cutting precision, and belongs to the technical field of sponge processing. The sponge with water absorbability and air permeability is humidified on line, the sponge is continuously cut on line under the condition of maintaining the water absorption saturation of the sponge, and the cut sponge is dehydrated. The invention has the advantages of straight and neat fracture, high cutting precision and the like.

Description

Method for improving online cutting precision of sponge

Technical Field

The invention belongs to the technical field of sponge processing, and relates to a method for improving sponge online cutting precision.

Background

The sponge is a porous elastic material, particularly polyurethane soft foam sponge, has water absorbability, air permeability and deformation recoverability, and is commonly used as filler for automobile seats, sofas and other products. Because the sponge is rich in ductility, the precision is low in the slitting process, and undesirable phenomena such as burrs and tool marks of fractures are easily formed, the low sponge cutting precision not only affects the overall quality of finished sponge blocks or sponge blanks, but also reduces the utilization rate of the sponge, so that more sponge leftover materials are generated, particularly in the continuous online cutting process, if the sponge blocks or the sponge blanks cannot be cut orderly at one time, the processes of secondary cutting and trimming are needed, the labor waste is serious, the sponge production enterprises, except for the foaming workshop, the sponge slitting workshop is the most important link, the sponge slitting workshop is also a workshop with intensive labor force, and the automatic production and the automatic high-precision cutting are difficult to realize. The high-precision translation conveying of the sponge is difficult due to the flexibility of the sponge, the sponge cannot be cut with high precision due to the deformation of the sponge caused by cutting resistance, the reject ratio is high, and great waste exists.

Under the condition that certain resistance exists between the continuously cut sponge and a cutter, two deformation modes are generally adopted, other substances (sponge powder is fused onto a blade) are adhered on the cutter to cause local passivation of a blade edge or unstable running of the sponge, the sponge is arched upwards (as shown in fig. 11) or port upwards (as shown in fig. 12) due to the fact that the sponge is not smoothly cut, in the cutting process that the sponge continuously and stably runs and the cutter is not disturbed, the sponge shown in fig. 11 and 12 is deformed due to the flexibility and the light weight of the sponge, only the deformation amplitude is small, the deformation can seriously affect the cutting quality of the sponge, and the fracture is uneven, misplaced, non-predetermined track deviation and the like after the sponge is reset occur.

Chinese patent [ cn201921942649.X ] discloses a sponge processing equipment, through setting up humidification room and freezer, can dehumidify the sponge and freeze again, then cuts, can guarantee that the sponge does not warp in the cutting process to improve the cutting quality of sponge. However, it is not difficult to see that it has the following drawbacks: 1. the sponge freezing time is long, and the online continuous and efficient cutting cannot be realized; 2. the freezing mode after humidification is easy to cause sponge grid damage due to uncontrollable crystal formation, volume change and the like in the liquid-solid phase change process of water, particularly under the condition of quick freezing; 3. the moisture content of the sponge is difficult to control, and if the moisture content is too high, the mesh is bonded and deformed in the freezing process, so that the thawed and restored sponge is not neat in cutting position, and if the moisture content is too low, the hardening effect is difficult to achieve; 4. the low-density sponge is difficult to solidify in a humidifying and freezing mode, and the breakage of grids in the cutting process is easily caused due to uneven crystal distribution and large pores; 5. the deformation of the sponge can be aggravated by the sinking of water in the freezing process, and the grids are easy to collapse in the bearing process of the bottom of the sponge, so that the performance of the sponge is damaged, and the initial state of the sponge is difficult to maintain in the long solidification process.

Disclosure of Invention

The invention aims to provide a method for improving the online cutting precision of sponge aiming at the problems in the prior art, and the technical problem to be solved by the invention is how to improve the cutting precision of sponge.

The purpose of the invention can be realized by the following technical scheme: a method for improving sponge on-line cutting precision is characterized in that sponge with water absorption and air permeability is humidified on line, the sponge is continuously cut on line under the condition that the water absorption saturation of the sponge is maintained, and the cut sponge is dehydrated.

Furthermore, the water on the cut sponge is returned, and the uncut sponge is humidified.

Further, the cut sponge is dehydrated in two steps, namely extrusion dehydration and drying dehydration.

Furthermore, hot water vapor generated in the drying process is used for humidifying and preheating the sponge before cutting.

Further, utilize the relatively poor characteristic of sponge humidification to saturation back gas permeability, adsorb the mode of the lateral wall of sponge thickness direction through the negative pressure, draw the sponge outward promptly after the cutting to make the sponge fracture keep away from the cutter, avoid the cutter to cause the secondary cutting to the sponge.

Further, the axis of the cutter head for cutting the sponge is positioned below the bottom surface of the sponge, so that the rotating direction of the cutter head is consistent with the rotating direction of the conveying roller for driving the sponge to translate.

The sponge density is increased, the flexibility is weakened and the shape-keeping performance is better by a humidifying mode, because the sponge with a porous structure absorbs water to saturation, the water filled in pores increases the self weight of the sponge, the resistance of overflowing accumulated water in extrusion pores needs to be overcome when the sponge after water absorption is deformed under pressure, and the resistance of overflowing air from the sponge pores only needs to be overcome when the sponge without water absorption is deformed under pressure.

Because the anti deformability reinforcing of sponge after absorbing water, dead weight increase, under the condition of the same cutter and sponge translation rate, this scheme can make the sponge cutting in-process take place that the range of deformation is littleer, therefore the fracture is more level and more smooth to the cutting accuracy of sponge has been improved.

In addition, the dead weight of the sponge after water absorption is increased, the rotating direction of the cutter head is controlled, the bearing part of the cutter head is firstly contacted with the bottom of the sponge, the amplitude of upward convex deformation of the cutting position of the sponge caused by thrust generated by the cutter head on the sponge can be reduced, and the dead weight of the sponge after water absorption to saturation is increased by tens of times compared with that before water absorption, so that the sponge can be almost ensured not to generate upward convex deformation by adopting the above mode.

The scheme greatly improves the cutting precision of the sponge, particularly the cutting of the thin sponge, and because the thin sponge is easy to deform such as arching, transverse bending and the like at the contact part of the cutting edge in the continuous cutting process, and because the flexibility of the thin sponge is higher, the probability of the sponge deviating, misplacing, wrinkling and the like during the translation of the conveying belt is higher; in the scheme, the self weight and the deformation resistance of the water absorption device are improved in a water absorption mode, so that the movement precision of the water absorption device is easy to control.

Traditional sponge dry-type cutting mode still has dust pollution's problem, and in this scheme, through to the saturation that absorbs water to the sponge humidification, thoroughly eliminated the dust problem among the sponge cutting process.

The traditional sponge dry-type cutting mode has the condition that the sponge fracture is blackened at high temperature, because the cutting tool and the sponge continuously and rapidly generate heat by friction, when the temperature reaches a certain value, the sponge or scraps generated by cutting can be burnt, so that the fracture is blackened; in this scheme, because the existence of water, can reduce the heat that the cutting produced by a wide margin, avoid gathering hot emergence.

The sponge is longitudinally deformed due to the self weight of the sponge, so that the pores of the sponge are gradually reduced from top to bottom, the uniform water content of each part refers to each part at the same height, but not each part of a longitudinal section, when the sponge is longitudinally cut, the cutting precision of the sponge cannot be influenced because the water content of each longitudinal part of the sponge is different, and the cutting plane is also a longitudinal plane because the sponge is uniformly longitudinally compressed, so the cutting precision cannot be influenced.

It is thus clear that this scheme can realize continuous, the sponge on-line cutting of high accuracy, and this scheme essence lies in utilizing the anti deformability of sponge that absorbs water reinforcing, dead weight increase, characteristics such as gas tightness promote by a wide margin, makes the cutting accuracy of sponge improve.

Drawings

FIG. 1 is a schematic structural diagram of the sponge on-line cutting system.

Fig. 2 is a flow chart of an on-line sponge cutting process.

FIG. 3 is a cross-sectional view of the sponge on-line cutting system.

Fig. 4 is a schematic perspective view of a humidifying conveyor belt, an extruding dewatering conveyor belt or a drying dewatering conveyor belt.

Fig. 5 is an overall schematic view of the upper and lower carrier conveyors.

Fig. 6 is a schematic view of the structure of fig. 5 with the upper and lower carrier conveyors removed.

Fig. 7 is a schematic structural diagram of the limiting plate.

Fig. 8 is a sectional view of a state where two limiting plates hold a sponge to be cut.

Fig. 9 is an enlarged view of a portion a in fig. 3.

Fig. 10 is an exploded view of a double-layer structure of a humidifying conveyor belt, a lower carrying conveyor belt, an upper carrying conveyor belt, an extruding dewatering conveyor belt and a drying dewatering conveyor belt.

FIG. 11 is a schematic diagram illustrating the arching of the sponge caused by the movement of the knife relative to the sponge in a conventional sponge cutting mode.

FIG. 12 is a schematic diagram illustrating the contraction of the sponge in the middle of the two sides of the sponge caused by the movement of the knife relative to the sponge in the conventional sponge cutting method.

Fig. 13 is a schematic diagram of the principle that two parts of the cut sponge are pulled apart to two sides of the cutter due to poor air permeability after the sponge is humidified in the scheme.

In the figure, a sponge to be cut; 1. a frame; 2. a conveying roller; 31. humidifying the conveying belt; 32. a humidifying water tank; 41. a cutter head; 42. a lower load-bearing conveyor belt; 43. a servo motor; 44. an upper load-bearing conveyor belt; 45. a limiting plate; 46. a rotating rod; 47. a vent gap; 48. a negative pressure chamber; 51. extruding a dehydration conveyer belt; 52. a water-saving tank; 53. a water squeezing roller; 61. drying the dehydration conveyor belt; 62. an air filter box; 63. heating the strip; 64. a collection hood; 65. a reflow hood; 66. a breather pipe; 67. an air pump; 71. an inner layer of gum; 72. a water-absorbing surface layer.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.

As shown in fig. 1, 3, 4, 5, 6, 7, 8 and 9, the high-precision sponge online cutting system comprises a sponge conveying line, a sponge humidifying mechanism, a sponge cutting mechanism and a sponge dewatering mechanism are sequentially arranged on the sponge conveying line along the sponge moving direction, the sponge humidifying mechanism can enable sponge to be in a water absorption saturation state before cutting, the sponge cutting mechanism comprises a cutter disc 41 capable of cutting sponge in the sponge moving process, and the sponge dewatering mechanism can restore the cut sponge to a state before humidifying.

The sponge transfer chain includes frame 1 and rotates a plurality of conveying rollers 2 of connecting in frame 1, and conveying roller 2 is parallel with the axis of blade disc 41, and the direction of rotation of blade disc 41 is unanimous with the direction of rotation of conveying roller 2, and the axis of blade disc 41 is located under the sponge lower surface.

The sponge density is increased, the flexibility is weakened and the shape-keeping performance is better by a humidifying mode, because the sponge with a porous structure absorbs water to saturation, the water filled in pores increases the self weight of the sponge, the resistance of overflowing accumulated water in extrusion pores needs to be overcome when the sponge after water absorption is deformed under pressure, and the resistance of overflowing air from the sponge pores only needs to be overcome when the sponge without water absorption is deformed under pressure.

Because the anti deformability reinforcing of sponge after absorbing water, dead weight increase, under the condition of the same cutter and sponge translation rate, this scheme can make the sponge cutting in-process take place that the range of deformation is littleer, therefore the fracture is more level and more smooth to the cutting accuracy of sponge has been improved.

In addition, the dead weight of the sponge after water absorption is increased, the rotating direction of the cutter disc 41 is controlled, the bearing part of the cutter disc 41 is firstly contacted with the bottom of the sponge, the amplitude of upward convex deformation of the cutting position of the sponge caused by thrust generated by the cutter disc 41 on the sponge can be reduced, and the dead weight of the sponge after water absorption to saturation is increased by tens of times compared with that before water absorption, so that the sponge can be almost ensured not to generate upward convex deformation by adopting the above mode.

According to the scheme, the cutting precision of the sponge is greatly improved, particularly the cutting of the thin sponge, because the thin sponge is easy to deform such as arching and transverse bending at the contact part of the cutting edge in the continuous cutting process, and because the flexibility of the thin sponge is high, the probability of the sponge generating the conditions of deviation, dislocation, folding and the like is high when the conveying belt translates; in the scheme, the self-weight and the deformation resistance of the water absorption device are improved in a water absorption mode, so that the moving precision of the water absorption device is easy to control.

Traditional sponge dry-type cutting mode still has dust pollution's problem, and in this scheme, through to the saturation that absorbs water to the sponge humidification, thoroughly eliminated the dust problem among the sponge cutting process.

The traditional sponge dry-type cutting mode also has the condition of high-temperature blackening of sponge fractures, because the cutting tool and the sponge continuously and rapidly rub to generate heat, when the temperature reaches a certain value, the sponge or scraps generated by cutting can be burnt, and the fractures are blackened; in this scheme, because the existence of water, can reduce the heat that the cutting produced by a wide margin, avoid gathering hot emergence.

The sponge humidifying mechanism comprises a humidifying conveying belt 31 positioned on the sponge conveying line and a humidifying water tank 32 positioned below the humidifying conveying belt 31, wherein a straight section of the humidifying conveying belt 31, which is in contact with the bottom surface of the sponge, is positioned above the liquid level of the humidifying water tank 32, the other straight section of the humidifying conveying belt 31 is positioned below the liquid level of the humidifying water tank 32, and the humidifying conveying belt 31 has water absorption.

If the sponge is directly humidified by soaking, the following defects exist: 1. the sponge conveying line needs to be complete, so that the humidifying position sinks, which is unfavorable for the straight conveying precision of the sponge; 2. the mode of direct soaking makes in the sediment such as sponge bits powder that aquatic probably exists get into the sponge hole easily, influences the sponge quality, and the impurity of remaining in the sponge hole is difficult to the clearance.

In this scheme, carry out the humidification to the sponge through the indirection of humidification conveyer belt 31, can reduce the probability that impurity got into in the sponge hole, can also ensure that the sponge is straight to be carried.

Specifically, when the moisture absorbed by the moisture-absorbing humidification conveyor 31 comes into contact with the sponge having a small water content, part of the moisture on the humidification conveyor 31 enters the sponge, and indirect humidification is continuously performed until the sponge is saturated with the water.

The sponge cutting mechanism comprises a lower bearing conveyer belt 42 which is arranged on the sponge conveyer belt, is connected with the humidifying conveyer belt 31 and is positioned behind the humidifying conveyer belt 31, the lower bearing conveyer belt 42 comprises two belt bodies, an avoiding gap corresponding to the cutter head 41 is formed between the two belt bodies, and the cutter head 41 is driven by a servo motor 43; the lower carrying conveyer 42 is located above the humidifying water tank 32, and the lower carrying conveyer 42 has water absorbability.

The frame 1 is provided with an upper bearing conveyer belt 44 which is positioned above the lower bearing conveyer belt 42 and symmetrically distributed on the two upward sides of the sponge with the lower bearing conveyer belt 42, and a sponge shape-preserving channel matched with the sponge in size is formed between the upper bearing conveyer belt 44 and the lower bearing conveyer belt 42.

The sponge shape-preserving channel is used for rectifying, righting and shape-preserving the positions of the sponge before and after cutting, the sponge entering the sponge shape-preserving channel and the sponge positioned in the sponge shape-preserving channel are in a continuous water replenishing state, and water absorption saturation of the sponge is ensured, because only the water absorption saturation can ensure that the water content of each part of the sponge is uniform, the sponge shape-preserving channel is also used for keeping high-precision cutting.

The sponge can possibly have the conditions of local extrusion, local deformation, local dehydration and the like in the process of entering the sponge shape-preserving channel, and the sponge shape-changing part can be promoted to reset and the water content is uniform after the sponge is continuously humidified until the water absorption is saturated.

Go up to bear conveyer belt 44 and bear and be provided with two absorption positioning mechanism that are located sponge guarantor type passageway both sides respectively between the conveyer belt 42 down, adsorb positioning mechanism and include a limiting plate 45, a ventilation window has been seted up to limiting plate 45 inboard, ventilation window department is provided with a plurality of bull sticks 46 of rotating connection on limiting plate 45, each bull stick 46 is parallel to each other, form a ventilation gap 47 between the adjacent bull stick 46, a negative pressure chamber 48 has in the limiting plate 45, two absorption positioning mechanism's negative pressure chamber 48 communicate with each other, one of them negative pressure chamber 48 links to each other with the negative pressure air supply.

The innermost circumference of the rotating rod 46 is tangent to the plane of the inner side surface of the limiting plate 45.

The air permeability of the sponge after water absorption is weakened, under the condition of water absorption saturation, negative pressure air flow can act on the side face of the sponge, so that the two sides of the sponge are subjected to external tension, and under the condition that the sponge shape maintaining channel is slightly larger than the width of the sponge, the mode that the sponge side wall is adsorbed by negative pressure can avoid secondary cutting of the cut sponge by the cutter disc 41, so that scratches and burrs are avoided from occurring on fractures of the sponge.

Specifically, the thickness of the sponge is greater than the height of the strip-shaped ventilation gaps 47 which are longitudinally distributed, the ventilation gaps 47 are located in the middle of the side walls of the sponge, slight height differences are formed between the top of the rotating rod 46 and the top surface of the sponge and between the lower end of the rotating rod 46 and the bottom surface of the sponge, the rotating rod 46 can reduce the pushing resistance of the sponge, the inner side end of the rotating rod 46 is flush with the inner side surface of the limiting plate 45 where the rotating rod 46 is located, so that the side walls of the sponge can be under the action of negative pressure, when the sponge is divided into two parts, the two sponge strips are pulled outwards behind the cutter disc 41, as shown in fig. 13, the gap between the two sponges is slightly greater than the thickness of the cutter disc 41, and the secondary cutting of the section of the sponge by the cutter disc 41 is avoided.

The sponge dewatering mechanism comprises an extrusion dewatering conveying belt 51 which is arranged on a sponge conveying line, is connected with the lower bearing conveying belt 42 and is positioned behind the lower bearing conveying belt 42, a water-saving water tank 52 is arranged below the extrusion dewatering conveying belt 51, a plurality of wringing rollers 53 are respectively arranged on the upper side and the lower side of a straight section of the extrusion dewatering conveying belt 51, which is close to the bottom of the water-saving water tank 52, the wringing rollers 53 are rotatably connected to the frame 1, and the extrusion dewatering conveying belt 51 has water absorption.

Sponge dewatering mechanism is still including setting up on the sponge transfer chain, with extrude dehydration conveyer belt 51 and link up, be located the stoving dehydration conveyer belt 61 after extruding dehydration conveyer belt 51, the below of stoving dehydration conveyer belt 61 is provided with an air filter box 62, be provided with the heating strip 63 that is located stoving dehydration conveyer belt 61 below in the air filter box 62, stoving dehydration conveyer belt 61 top is provided with one and collects cover 64, humidification conveyer belt 31 top is provided with a backward flow cover 65, be provided with a breather pipe 66 between backward flow cover 65 and the collection cover 64, be provided with an air pump 67 on the breather pipe 66.

Because extrude dehydration conveyer belt 51 and have hydroscopicity, its continuous moisture absorption with on the sponge, then extrude dehydration conveyer belt 51's mode through wringing roller 53 extrusion, make thinner sponge can quick dehydration, if sponge thickness is great, can increase the length of extruding dehydration conveyer belt 51 to it is obvious to make the dehydration effect, also can set up many and extrude dehydration conveyer belt 51 and dewater the sponge repeatedly.

After preliminary extrusion dehydration, the dehydration of drying again, set up the heating strip in the sponge below, heat drying dehydration conveyer belt 61, heat transfer to the sponge above it, make the evaporation of water in the sponge, the mode of cooperation bleeding will carry on the steam delivers to the sponge before the cutting, this not only can make water reutilization, can also make the sponge have a temperature that is a little higher than normal atmospheric temperature before the cutting, so that can accelerate the formation of steam after the cutting, thereby shorten the length of drying dehydration.

As shown in fig. 10, the humidifying conveyer belt 31, the lower bearing conveyer belt 42, the upper bearing conveyer belt 44, the extrusion dewatering conveyer belt 51 and the drying dewatering conveyer belt 61 all include a colloid inner layer 71 and a water absorbing surface layer 72; the inner layer 71 is a net structure.

The humidifying conveyer belt 31, the lower bearing conveyer belt 42, the upper bearing conveyer belt 44, the extrusion dehydration conveyer belt 51 and the drying dehydration conveyer belt 61 are all soft belts which are connected end to end and are drawn between the two conveyer rollers 2, and in order to maintain the straight state of the sponge placed on the conveyer belts, a rotatable support rod can be arranged on the lower surface of the conveyer belt at the bottom of the sponge; the conveying rollers 2 rotate synchronously at the same speed and in the same direction in a mode that gears at the end parts are meshed alternately, and the synchronous operation of the conveying belts is ensured.

The colloid inner layer 71 is made of rubber and other materials, and the reticular structure of the colloid inner layer can ensure the permeability of water vapor in the humidifying, dehydrating and other processes; the water absorption surface layer 72 can be sponge or cloth, if the thickness of the sponge a to be cut is large, the water absorption surface layer 72 can be set to be sponge with large water absorption rate due to the requirements of indirect humidification and indirect dehydration efficiency, if the sponge a to be cut is thin, the water absorption surface layer 72 can be cloth, and the water absorption surface layer 72 is adhered to the outer side surface of the colloid inner layer 71.

The accumulated water in the water-saving water tank 52 is pumped to the humidifying water tank 32 after being filtered, the humidifying water tank 32 is connected with a water source, and a valve switch for controlling the water level is arranged between the humidifying water tank 32 and the water source.

In the above, it is mentioned that the sponge has uniform water content in each part under the condition of water saturation, and it is noted that: because sponge dead weight causes the longitudinal deformation of sponge and can cause the sponge to reduce from top to bottom the hole gradually, each position moisture content homogeneous mentioned above means each position of same height, and not longitudinal section's each position, when vertically cutting, the cutting precision that the sponge can not be influenced to the longitudinal direction moisture content difference of each position of sponge, because the sponge is even longitudinal compression, and the cutting plane also is the longitudinal plane, so can not influence cutting precision.

It is thus clear that this scheme can realize continuous, sponge on-line cutting of high accuracy, and this scheme essence lies in utilizing the sponge resistance to deformation reinforcing of absorbing water, dead weight increase, characteristics such as gas tightness promote by a wide margin, makes the cutting accuracy of sponge improve, and the whole process of this scheme is as shown in figure 2.

If transverse slicing is needed, the cutter disc 41 is only required to be properly adjusted to be horizontal, the rotating rod 46 for drawing sponge by suction is adjusted to be transverse, and adaptive adjustment of the structure is added, and cutting of other tracks can be realized after the structure is properly adjusted.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Claims (4)

1. A method for improving sponge on-line cutting precision is characterized in that sponge with water absorption and air permeability is humidified on line, the sponge is continuously cut on line under the condition of maintaining water absorption saturation of the sponge, and the cut sponge is dehydrated;

by utilizing the characteristic that the sponge has poor air permeability after being humidified to be saturated, the sponge is pulled outwards after being cut in a mode that the side wall in the sponge thickness direction is adsorbed by negative pressure, so that the sponge fracture is far away from the cutter, and the secondary cutting of the sponge caused by the cutter is avoided;

the axis of the cutter head for cutting the sponge is positioned below the bottom surface of the sponge, so that the rotating direction of the cutter head is consistent with the rotating direction of the conveying roller for driving the sponge to translate.

2. The method for improving the sponge on-line cutting precision as claimed in claim 1, wherein the water separated from the cut sponge is returned to humidify the uncut sponge.

3. The method for improving the online cutting precision of the sponge as claimed in claim 2, wherein the cut sponge is dehydrated in two steps, namely squeezing dehydration and drying dehydration.

4. The method for improving the sponge on-line cutting precision as claimed in claim 2, wherein the hot water vapor generated in the drying process is used for humidifying and preheating the sponge before cutting.

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