JPH078993U - Net heater - Google Patents

Abstract

(57) [Abstract] [Purpose] Especially, reticulated heat generation, which is particularly suitable for electric hotbeds for raising and cultivating seedlings in the fields of agriculture and horticulture, or for electric hotbeds for heating and growing in the field of planting such as building rooftops. With respect to the body, it is to obtain a net heater having more preferable characteristics as a planar heating element for planting, facilitating knitting work, and having both flexibility and strength. A net in which a warp group including a plurality of exothermic net yarns 1 having at least one exothermic yarn 2 and a weft yarn group of insulating net yarns 7 are netted by a through type round knotless knitting machine. In the heater, the heat-generating mesh yarns 1 were arranged at intervals with a wide center and narrow sides. Further, in the net heater having the above structure, the outer layer 5 of the insulating coating film 4 of the heat generating yarn 2 has a polyester multi-fiber braid finish. Also, at least one heating thread 2
The exothermic mesh yarn 1 is formed by twisting the two strands containing the above, and the twist coefficient, that is, the ratio of the yarn length of the exothermic yarn before twist to the finished mesh yarn length is 1.1 to 1.5. To do.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a reticulated heating element which is particularly suitable for an electric hotbed for raising and cultivating seedlings mainly in the fields of agriculture and horticulture, or an electric hotbed for heating and raising plants in the field of planting such as a rooftop of a building. is there.

[0002]

[Prior art]

 It is known to obtain a net heater that generates heat in a plane by energizing by knitting a heat generating net yarn including a heat generating yarn as a warp or a weft. As a heating element, it has been proposed to use a spun yarn obtained by mixing aramid short fibers and stainless short fibers in addition to a normal heating wire (JP-A-3-165485). An insulating coating of polyurethane resin, polyester resin, polyamide resin, polyvinyl chloride resin, or the like is provided on the conductive wire to form a heating thread used as a net thread.

[0003] A fish net is constructed by twisting two such heating yarns and knotlessly knitting them to heat the surface to 50 ° C or more to prevent the adhesion and growth of marine microorganisms. It is disclosed in Japanese Patent No. 346733. Further, a snow melting net in which such a heating yarn and a mesh yarn of amide filaments are cross-knitted to form a square mesh having the same size as the whole mesh is disclosed in Japanese Utility Model Publication No. 62-103921. .

[0004]

[Problems to be solved by the device]

 This invention is a research for using the net heater having the above structure as a heating element for raising and cultivating seedlings in the fields of agriculture and horticulture or as a heating element for heating the cultivation floor when planting on the roof of a building. This is done as a part of the above, and an object is to obtain a net heater that has more preferable characteristics as a planar heating element for planting, is easy to braid, and has both flexibility and strength.

[0005]

Means for Solving the Problems A net heater according to the present invention penetrates a warp group including a plurality of exothermic net threads 1 having at least one exothermic thread 2 and a weft group of insulating net threads 7. In a net heater finished in a mesh shape with a circular round knotless knitting machine, the heat-generating mesh yarns 1 of the mesh 8 knitted in a predetermined length and width are arranged at intervals with wide central part and narrow side parts. Characterize.

Further, in the net heater having the above-mentioned configuration, the outer layer 5 of the coating 4 made of the insulating resin of the heating yarn 2 is made of polyester multi-fiber braid. Further, the exothermic mesh yarn 1 is formed by twisting two strands including at least one heat-generating yarn 2, and the twist coefficient of the two strands, that is, the yarn length and finish of the exothermic yarn before twisting. The ratio to the length of the braided yarn is set to 1.1 to 1.5.

[0007]

[Action]

 The net heater is an electric hotbed for preventing snow melting and freezing outdoors and raising seedlings and cultivation in the fields of agriculture and horticulture, or a net-like heating element for heating and growing in the field of planting inside and outside the building. When used in a greenhouse in a field, convection occurs in which cold air descends along the wall surface of the greenhouse and warm air rises in the center of the greenhouse. Therefore, the temperature of the side of the floor of the vinyl house near the wall of the house tends to be lower than that of the center. In addition, when a nursery is installed in a greenhouse, wooden boards or blocks are used for partitioning the frame, but even in such facilities, the temperature on the side near the partition surface is higher than that at the center. It tends to be low temperature. In the net heater of the present invention, the heat-generating net yarn 1 having the heat-generating yarn 2 can be densely arranged in the side portion at a narrower interval than in the central portion. It is possible to have a uniform temperature distribution throughout the cultivation bed inside the plant, so that the plants can germinate well and be uniform over the entire area.

Further, the heating yarn 2 used for the net heater is required to have excellent waterproof insulation and flexibility, but the insulating coating of the heating yarn 2 should not be impaired when the net is finished. When a soft insulating resin is used as the warp yarn, when the heating yarn 2 passes through the tension portion of the spindle of the knitting machine during the knitting process by the through-type round knotless knitting machine The heat-generating yarn 2 which is to be cut is easy to cut, and the insulating resin film is soft, so that the film is easily scratched by an external force during handling, which causes a problem that electrical insulation is deteriorated.

In the present invention, in order to impart sufficient flexibility and insulating effect to the heat-generating net yarn 1, a soft insulating coating such as polyvinyl chloride is provided on the inner layer 4, and the outer layer is further treated by a polyester blade treatment. 5 is provided to prevent the inner layer 4 of the insulating resin film from being scratched by an external force while the net heater is being used and handled, and to prevent the inner layer 4 of the insulating resin film from being deteriorated by ultraviolet rays when used outdoors.

Furthermore, by twisting two strands containing at least two heating yarns 2, the respective strands are tightly clamped to each other. Therefore, the friction between the strands is increased, and as a result, the heat generating net yarn 1 has a higher strength than the heat generating yarn 2 alone. In addition, since the twist imparts thickness, elasticity, and extension force to the heat-generating net yarn 1, as a result, the heat-generating surface area is increased due to the increase in the thickness, so that the heat efficiency is improved as compared with the case where only the heat-generating yarn 2 is used, and at the same time, the heat generation The mechanical strength of the reticulated net yarn 1 is also improved. Therefore, when it is buried in the ground and roads for the purpose of preventing snow melting and icing, it is durable against external force that repeatedly works and becomes an ideal mesh heating element with good thermal efficiency.

[0011]

【Example】

 1 to 3 are views showing an embodiment of the present invention. As shown in FIG. 3, the heat generating net yarn 1 is formed by twisting two heat generating yarns 2 and 2. Each heat generating yarn 2 is a spun yarn 3 obtained by mixing polyamide short fibers and stainless short fibers as a core yarn. The inner layer 4 made of a vinyl chloride resin insulating coating is provided thereon, and then the outer layer 5 of the insulating resin coating obtained by the polyester blade treatment is further provided. The figure shows two heating yarns 2 twisted together, but one heating yarn 2 and two ordinary synthetic resin long fibers commonly used such as polyethylene are twisted together. You can also do it.

FIG. 2 shows a knotted part of a net 8 formed by knitting a heat-generating net yarn 1 obtained by twisting two heat-producing yarns 2 as a warp and an insulating net yarn 7 as a weft. A threading type knotless portion is formed by passing the respective threads between the mesh threads 1 and 7 of the mating member in opposite directions.

FIG. 1 schematically shows the whole net heater of the present invention, in which the solid line is the heat-generating mesh yarn 1 and the dotted line is the insulating mesh yarn 7. As shown in the figure, only the heat-generating mesh yarn 1 is used as the warp in the side portion of the mesh 8, and the heat-generating mesh yarn 1 is formed in the center of the mesh 8 Two warp threads are inserted. In addition, in the intermediate portion between the central portion and the side portion, a warp yarn made of one insulating net yarn 7 is inserted between the warp yarns made of the heat generating net yarn 1. All the wefts are insulating mesh yarns 7. The mesh of the embodiment shown in the drawing has a width of 1.8 m and a length of 3.6 m, and forms a square mesh having 22 meshes in the width direction and 44 meshes with 82 meshes on each side in the length direction.

In such a net 8, a heat generating net yarn 1 and an insulating net yarn 7 arranged between them are arranged in a warp direction at a predetermined interval by a through type circular knotless knitting machine, An insulating mesh yarn 7 is arranged in the weft direction intersecting with it to perform an endless knitting mesh, and the finished tubular mesh is cut in the warp direction to provide insulation between the heat-generating mesh yarns 1 in the length direction. The mesh yarn 7 is arranged, and the mesh net 8 having a square finish in which only the insulating mesh yarn 7 is arranged in the width direction is manufactured.

In the example of FIG. 1, fifteen exothermic mesh threads 1 pass in the longitudinal direction of the mesh 8, one end 11 of which is entirely conducted by the cable 12, and the other end 13 of which is 5 each. It is connected to the strands of the three-phase captyre cable 14 and is energized with three-phase 200 volts by a three-phase star connection. When the same net is used with a single phase of 100 volts, 15 exothermic net yarns 1 are connected in parallel. The connecting portion between the heat generating yarn 2 of the heat generating net yarn 1 and the cables 12 and 14 is connected with a crimping sleeve, and then the connecting portion is set in a mold and resin-molded to obtain sufficient water resistance and strength. Is being considered.

[0016]

[Effect of device]

 Since the net heater of the present invention configured as described above has a net shape, it has excellent water permeability and air permeability even when embedded in soil, and does not impair the water permeability and air permeability of the cultivated soil. In addition, since the heating yarns are arranged closely at the sides of the net and coarse at the center, the temperature of the cultivation floor can be made uniform when installed in a greenhouse. Further, by using two insulating layers as the heat generating yarn insulating layer and forming the outer layer thereof by the polyester blade treatment, it is possible to give the heat generating yarn sufficient flexibility and to prevent damage to the insulating film during use and handling. Prevents deterioration and improves slippage during knitting to prevent yarn breakage. Furthermore, by twisting the strand containing the heating yarn to form a heat-generating net yarn, it is possible to obtain an ideal net-like heating element with good durability and durability even when buried in the ground or on the road. it can.

[Brief description of drawings]

FIG. 1 is a plan view schematically showing a net heater according to an embodiment.

[Figure 2] Enlarged view of the nodule

FIG. 3 is an enlarged view of a heat-generating mesh yarn.

[Explanation of symbols]

 1 Heat generating net yarn 2 Heat generating yarn 4 Inner layer 5 Outer layer 7 Insulating net yarn 8 Net

Claims (3)

[Scope of utility model registration request] 1. A through-type round knotless knitting method comprising a warp group including a plurality of heat-generating net yarns (1) having at least one heat-generating yarn (2) and a weft yarn group of insulating net yarns (7). In a net heater finished in a mesh shape with a mesh machine, a mesh that is knitted in a predetermined length and width.
A net heater characterized in that the heat-generating net yarn (1) of (8) is arranged with a wide central part and narrow side parts. 2. The net heater according to claim 1, wherein the outer layer (5) of the coating (4) of the heat-generating yarn (2) made of an insulating resin has a polyester multi-fiber braid finish. 3. An exothermic mesh yarn (1) formed by twisting two strands containing at least one exothermic yarn (2), the twist coefficient of the two strands, that is, before twisting. The net heater according to claim 1 or 2, wherein the ratio of the yarn length of the heat generating yarn to the finished mesh yarn length is 1.1 to 1.5.