CN108859032B

CN108859032B - Heating charging barrel

Info

Publication number: CN108859032B
Application number: CN201810799008.7A
Authority: CN
Inventors: 陈明华
Original assignee: Gienkee Plas Science & Technology (suzhou) Co ltd
Current assignee: Gienkee Plas Science & Technology (suzhou) Co ltd
Priority date: 2018-07-19
Filing date: 2018-07-19
Publication date: 2023-01-06
Anticipated expiration: 2038-07-19
Also published as: CN108859032A

Abstract

The invention discloses an integral heating charging barrel and a production method thereof, wherein the integral heating charging barrel comprises a charging barrel and a heating device, the heating device is arranged outside the charging barrel and sequentially comprises an insulating heat conduction layer, an electric heating foil strip and an insulating heat insulation layer from inside to outside, the cross section of the electric heating foil strip is a rectangle with the length-width ratio larger than ten, the outer side of the insulating heat insulation layer is also provided with a heat insulation layer, and the integral heating charging barrel further comprises a junction block and a thin plate protection tightening layer.

Description

Heating charging barrel

Technical Field

The invention relates to a heating charging barrel, in particular to a heating charging barrel in plastic machinery.

Background

Plastic machines, such as injection molding machines, are machines that heat a polymeric raw material through a barrel of a molding machine to a temperature required for production, to a molten state, and then inject the polymeric fluid heated to the molten state into a mold through a screw to cool and mold the polymeric fluid. Plastics are now one of the most widely used and important materials for human beings, and have various processing modes, wherein plastic injection molding is the most advantageous and the most important processing mode for plastic products.

The quality of injection molding products is influenced by four aspects of high polymer materials, molds, injection molding machinery and injection molding process, the temperature of a charging barrel of an injection molding machine is one of important parameters in the injection molding processing process, and effective heating of plastics by the charging barrel is an important link for ensuring the molding quality of plastic products. In the heating process, the temperature of the charging barrel can influence the rheological property of the molten plastic, the melt temperature is too high, quality defects such as warping, scorching and the like are easily formed, the melt temperature is too low, the plastic plasticizing degree is not uniform, the flowing property is reduced, the injection of the molten plastic is not facilitated to fill a mold cavity, and quality defects such as short jet, flow marks and the like are easily formed.

In the prior art, the heating mode of the charging barrel is mainly heated by a heating ring fastened on the charging barrel. The heating ring has: ceramic heating rings, mica heating rings, cast aluminum heating rings, cast copper heating rings, and the like. They are characterized in that the heating ring is arranged on the surface of the charging barrel independently from the charging barrel in two parts. Because an installation gap exists between the heating ring and the charging barrel, the heat conduction efficiency is low, the heat transfer path between the heating wire and the charging barrel is long, the temperature gradient between the heating wire and the charging barrel is large, even part of the heating wire is burnt due to overhigh heat load, or the service life is rapidly reduced. The electromagnetic induction heating mode is a new heating technology, the heating efficiency is high, but a frequency conversion control cabinet is needed, the cost is high, the failure rate is high, the electromagnetic radiation is large, and the frequency conversion control cabinet consumes a part of electric energy. A quartz tube radiant heating coil is a heating coil that heats with thermal radiation, but it is easily damaged. The above methods of heating the cylinder usually require a heating unit in addition to the cylinder. These methods also have problems of low heat conduction efficiency, slow thermal response speed, and the like.

In the prior art, no heat preservation measure is arranged on the outer wall of a charging barrel of the injection molding machine, so that in the injection molding process, a large amount of heat of the charging barrel is dissipated to the environment, and in order to keep higher temperature in the charging barrel, the consumed electric energy is increased; meanwhile, the outer surface of the charging barrel is not provided with a heat insulation layer, and once a worker touches the charging barrel in the operation process, scalding accidents can be caused.

In view of the problems of uneven heating, low heat transfer efficiency, short service life of the heating wire, low thermal response speed caused by low heat transfer efficiency, and the like of the conventional heating material cylinder, how to design a heating material cylinder which has high heat transfer efficiency, simple structure and low cost is an urgent problem to be solved in the industry.

Disclosure of Invention

The invention discloses a heating charging barrel which comprises a charging barrel and a heating device, wherein the heating device is integrally arranged outside the charging barrel and sequentially comprises an insulating heat-conducting layer, an electric heating foil strip and an insulating heat-insulating layer from inside to outside.

Further, the cross section of the electric heating foil strip is rectangular.

Furthermore, the long side of the rectangle of the cross section of the electric heating foil strip is in contact with the charging barrel, and the length-width ratio of the rectangle is more than or equal to 10.

Furthermore, a temperature measuring hole is arranged in the middle of the charging barrel.

Furthermore, the outer side of the insulating layer is also provided with an insulating layer.

The invention also discloses a junction block for fixing the electric heating foil tape.

Furthermore, the junction block comprises a fixing screw, a line pressing screw, a threading groove and a groove, the electric heating foil strip penetrates through the groove to the threading groove, the line pressing screw fastens the electric heating foil strip in the threading groove, and the fixing screw fixes the junction block on the charging barrel.

Further, the material of the terminal block is ceramic.

Furthermore, the fixing screw is provided with a grounding wire.

Furthermore, the junction block also comprises a protective cover, and the protective cover is fixed outside the junction block through protective cover fixing screws.

Furthermore, the protective cover fixing screw is provided with a grounding wire.

Further, the material of the protective cover is ceramic.

The invention also discloses a method for producing the heating charging barrel, which comprises the following steps: step 1: the outer surface of the charging barrel is provided with an insulating heat conduction material; step 2: winding and fixing an electric heating foil belt outside the charging barrel; and 3, step 3: and an insulating material is arranged outside the electric heating foil tape.

Further, step 2 is divided into the following steps: step 2.1: an electric heating foil tape is fixed in the first wiring block, the electric heating foil tape penetrates through a threading groove in the first wiring block from a groove in the first wiring block, the electric heating foil tape is tightly pressed between the first wiring block and the insulating heat-conducting layer by the groove, and the first wiring block is fixed on the charging barrel; step 2.2: winding an electric heating foil tape outside the charging barrel; step 2.3: and fixing the second junction block to the charging barrel, and connecting the other end of the electric heating foil strip into the second junction block.

Further, step 2 is divided into the following steps: step 2.1: fixing a first wiring block on the charging barrel, and fixing an electric heating foil tape in the first wiring block; step 2.2: a protective cover is fixed on the first wiring block, and an electric heating foil tape is wound on the charging barrel; step 2.3: fixing a second junction block on the charging barrel, pressing the electric heating foil tape tightly, and connecting the electric heating foil tape into the second junction block; step 2.4: and fixing a protective cover on the second wiring block.

Further, a step 4 is added after the step 3: an insulating layer is additionally arranged outside the charging barrel.

Further, a step 5 is added after the step 4: and a thin plate protection tightening layer is additionally arranged outside the charging barrel heat-insulating layer.

Further, before step 1, a step is added: and (4) cleaning oil stains and scrap iron of the charging barrel.

In the invention, the electric heating foil strip can be fixed by adopting a wiring mode in the prior art, and a better fixing effect can be achieved if a wiring block is used. The wiring block adopts the following modes to carry out electrode wiring: the wiring block is fixed on the metal cylinder through one or more screws or bolts, the screws have the functions of fixing and grounding, and the safety of the metal cylinder is ensured through grounding; the junction block has a plurality of line ball screws, and the electric heat foil tape is fixed in the junction block by line ball screws, has two threading grooves in the middle of the junction block, and there are two recesses below, and the electric heat foil tape is through middle threading groove to recess in the bottom in order to reach the effect of tightening up, has guaranteed that the electric heat foil tape can hug closely on the insulating layer, in order to avoid the problem that local heating and feed cylinder are heated unevenly.

The invention can be applied to the heating of the cylinders of textile, plastic, rubber machines, for example.

The formula for heat transfer is:

Q＝K×A×T/L

wherein Q-heat, K-heat conductivity, A-area, T-temperature difference and L-thickness. The heat-conducting insulating layer has the advantages of large area A, complete circumference, small thickness L and large heat-conducting coefficient K. This means that, in the case of a comparatively small temperature difference T, a comparatively large amount of heat is transferred. The electric heating foil tape is used, so that the heat conduction area and the heat conduction speed are greatly increased. Therefore, the invention has high heat conduction efficiency and small temperature gradient. The effects achieved are as follows: energy saving, long service life and quick thermal response.

The invention also belongs to a heat conduction heating mode. The difference of the present invention from the existing heat conduction method is that the present invention adopts an integral heating method. The electric heating ring and the charging barrel in the prior art are two parts, an external force is required to tighten up and wrap the charging barrel so as to ensure the contact of the electric heating ring and the charging barrel, but because the electric heating ring and the charging barrel are gapped, the contact area is small, the heat conduction effect is poor and the heat conduction is uneven, the temperature of the heating element is high, the temperature gradient between the heating element and the heated element is large, the energy consumption is large, the local part is easy to overheat, and the service life is short.

According to the invention, the surface of the charging barrel is wrapped with an insulating material (such as mica paper) or coated with an insulating layer with higher heat conductivity coefficient, so that the heat conduction speed is increased, and the heat transfer between the electric heating foil strip and the charging barrel is more uniform and stable.

The invention adopts the electric heating foil tape with the cross section being a rectangle with the length-width ratio more than ten, and when the electric heating foil tape is wound outside the charging barrel, the contact area between the electric heating foil tape and the heat conduction insulating layer is effectively increased, and the heat transfer stability and the heat conduction efficiency are improved.

The invention also adopts the wiring block to enhance the wiring stability, the ceramic wiring block can be effectively insulated, and the grounding wire is arranged on the wiring block to be grounded so as to ensure that the charging barrel is grounded and is uncharged.

The heating device disclosed by the invention is attached to the shape of the charging barrel, can be integrated with the charging barrel into a whole, and does not need to be additionally provided with other heating devices, so that the space is effectively saved.

Drawings

FIG. 1 is an overall configuration diagram of a first embodiment of the present invention;

FIG. 2 is a cross-sectional view of a first embodiment of the present invention;

FIG. 3 is a schematic diagram of the connection of the junction block according to the first embodiment of the present invention;

FIG. 4 is a partially enlarged view of the wiring manner of the junction block according to the first embodiment of the present invention

Fig. 5 is one of the overall structural diagrams of the junction block of the first embodiment of the present invention;

FIG. 6 is a second block diagram of the junction block according to the first embodiment of the present invention;

FIG. 7 is a third block diagram of the junction block according to the first embodiment of the present invention;

FIG. 8 is a fourth drawing showing the overall construction of the junction block according to the first embodiment of the present invention;

FIG. 9 is an overall wiring schematic of the first embodiment of the invention;

FIG. 10 is a cross-sectional view of a junction block and a cartridge corresponding to FIG. 9;

fig. 11 is one of the overall structural views of a junction block of the second embodiment of the present invention;

fig. 12 is one of the overall structural views of the protective cover of the junction block according to the second embodiment of the present invention;

fig. 13 is a second overall structure diagram of a junction block according to the second embodiment of the present invention;

fig. 14 is a second overall structure diagram of the protective cover of the junction block according to the second embodiment of the invention;

FIG. 15 is a third drawing of the overall structure of a junction block according to the second embodiment of the present invention;

FIG. 16 is an overall wiring schematic of a second embodiment of the invention;

FIG. 17 is a cross-sectional view of a junction block, junction block protective cover and cartridge corresponding to FIG. 16;

the figure numbers:

1. charging barrel

2. Insulating heat-conducting layer

3. Electric heating foil belt

4. Insulating and heat-insulating layer

5. Junction block

6. Heat insulation layer

7. Temperature measuring hole

8. Junction block protective cover

9. Junction block

51. Line pressing screw

511. Press line screw hole

52. Fixing screw

53. Ground wire

54. Threading groove

55. Groove

56. Power line

57. Protective cover fixing screw

58. Fixing screw

59. Sheet protection tightening layer

591. Tightening layer fixing clamp

Detailed Description

Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the following description of the embodiments, for purposes of clearly illustrating the structure and operation of the present invention, directional terms are used, but the terms "front", "rear", "left", "right", "outer", "inner", "outer", "inward", "axial", "radial", and the like are to be construed as words of convenience and are not to be construed as limiting terms. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.

The first embodiment of the present invention is described below.

As shown in fig. 1 and 2, the heating cartridge of the first embodiment includes, in order from inside to outside, an insulating heat-conducting layer 2, an electric heating foil tape 3, an insulating heat-insulating layer 4, and an insulating layer 6. The junction block 5 is arranged on the insulating heat conduction layer 2 and the electric heating foil strip 3 and used for fixing the electric heating foil strip 3, enhancing the contact pressure of the electric heating foil strip 3 and the insulating heat conduction layer 1, and the junction block 5 is used as an electrode at the same time. The cross section of the electric heating foil strip 3 is a rectangular foil strip with the length-width ratio larger than ten, so that compared with a round resistance wire, the contact between the electric heating foil strip 3 and the insulating heat conduction layer 1 is surface contact. The insulating layer 4 is coated on the outer side of the electric heating foil 3 to play a role of insulating and heat insulation. The heat preservation 6 sets up in the 4 outsides of insulating thermal insulating layer, further promotes the heat preservation effect to with the high temperature separation in heat preservation 6, avoid the workman to contact and cause the scald. In order to reinforce the insulating layer 6, a thin plate protective tightening layer 59, which may be a metal sheet metal part, may be additionally provided outside the insulating layer 6, and a tightening layer fixing clamp 591 is provided. The middle part of the charging barrel is provided with a temperature measuring hole 7 which is mainly used for measuring the temperature inside the charging barrel, and the temperature measuring hole is usually selected to be avoided when the electric heating foil tape 3 is laid.

As shown in fig. 3 to 8, which are a schematic wiring diagram and a structural diagram of the junction block 5, the junction block 5 is fixed on the charging barrel 1 by 2 fixing screws 42 or bolts, the fixing screws 52 have fixing and grounding functions, and are grounded by a grounding wire 53, so that safety is ensured; junction block 5 has four line ball screw 51, and electric heat foil tape 3 is fixed in junction block 5 by line ball screw 51, and each has 1 threading groove 54 in junction block 5 both sides, and there are 2 recesses 55 the below, and electric heat foil tape 3 passes to threading groove 54 through recess 55 below to it is fixed by line ball screw 51 in threading groove 54.

The terminal block 5 is made of a ceramic material to improve the insulating property. The terminal block 5 may be replaced by an electrode; if the outside of the charging barrel is provided with a protection device, the heat-insulating layer can be eliminated.

A second embodiment of the present invention is described below.

As shown in fig. 11 to 17, the second embodiment mainly consists in the improvement of the terminal block and the protective cover thereof, and the other parts are the same as those of the first embodiment. In the second embodiment, the terminal block 9 is provided with a fixing screw 58 and a protective cover fixing screw 57, and the ground wire 53 is provided on the protective cover fixing screw 57. The second embodiment also shows a power cord 56.

The terms "first," "second," and the like, as used herein, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another, unless otherwise indicated. Similarly, the appearances of the phrases "a" or "an" in various places herein are not necessarily all referring to the same quantity, but rather to the same quantity, and are intended to cover all technical features not previously described. Similarly, modifiers similar to "about", "approximately" or "approximately" that occur before a numerical term herein typically include the same number, and their specific meaning should be read in conjunction with the context. Similarly, unless a specific number of a claim recitation is intended to cover both the singular and the plural, and embodiments may include a single feature or a plurality of features.

The embodiments described in the specification are only preferred embodiments of the present invention, and the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit the present invention. Those skilled in the art can obtain technical solutions through logical analysis, reasoning or limited experiments according to the concepts of the present invention, and all such technical solutions are within the scope of the present invention.

Claims

1. The heating charging barrel comprises a charging barrel and a heating device, and is characterized in that the heating device is installed outside the charging barrel and sequentially comprises an insulating heat-conducting layer, an electric heating foil strip and an insulating heat-insulating layer from inside to outside, a temperature measuring hole is formed in the middle of the charging barrel, a heat-insulating layer is arranged on the outer side of the insulating heat-insulating layer, a tightening layer is arranged on the outer side of the heat-insulating layer, the cross section of the electric heating foil strip is rectangular, the long side of the rectangle is in contact with the charging barrel, the rectangular length-width ratio is larger than or equal to 10, the electric heating foil strip is spirally wound outside the insulating heat-conducting layer and further comprises at least one wiring block, the wiring block is used for fixing and tightening the electric heating foil strip, the wiring block comprises a fixing screw, a line pressing screw, a threading groove and a groove, the electric heating foil strip is penetrated through the groove by the groove, the line pressing screw is fastened in the threading groove, the electric heating foil strip is fixed by the fixing screw, the wiring block is fixed on the charging barrel, and a fixing clamp is arranged on the tightening layer for tightening the tightening layer.

2. The heating cartridge of claim 1, wherein the material of the terminal block is ceramic.

3. A heating cartridge as claimed in claim 1 wherein said fixing screw is provided with an earth connection.

4. A heating cartridge as claimed in claim 1 wherein said junction block further comprises a protective cover secured to the exterior of the junction block by protective cover retaining screws.

5. A heating cartridge as claimed in claim 4 wherein said protective cover retaining screw is provided with a ground lead.

6. A heating cartridge as claimed in claim 4 wherein the material of the protective cover is ceramic.

7. A method of producing a heating cartridge, comprising the steps of:

step 1: the outer surface of the charging barrel is provided with an insulating heat conduction material;

step 2: arranging a first wiring block outside the charging barrel, fixing the electric heating foil tape in the first wiring block, enabling the electric heating foil tape to penetrate through a threading groove in the first wiring block from a groove in the first wiring block, fastening the electric heating foil tape in the threading groove by a line pressing screw, fixing the first wiring block on the charging barrel by a fixing screw, and spirally winding the electric heating foil tape outside the insulating heat-conducting material;

and step 3: fixing a second junction block on the charging barrel, pressing the electric heating foil tape tightly, and connecting the electric heating foil tape into the second junction block;

and 4, step 4: arranging an insulating and heat-insulating material outside the electric heating foil tape;

and 5: a heat insulation layer is additionally arranged outside the charging barrel;

and 6: and a tightening layer is additionally arranged on the outer side of the heat insulation layer, a fixing clamp is arranged on the tightening layer, and the fixing clamp is closed to tighten the tightening layer.

8. The method of claim 7, wherein step 2 is followed by the addition of a step of: fixing a protective cover on the first wiring block; and adding a step after the step 3: and a protective cover is fixed on the second wiring block.

9. The method of claim 7, wherein a step is added before step 1: and (4) cleaning oil stains and scrap iron of the charging barrel.