CN214592031U

CN214592031U - Heating plate

Info

Publication number: CN214592031U
Application number: CN202120506984.6U
Authority: CN
Inventors: 沈金明; 府震华; 孔清; 时文岗
Original assignee: Yancheng Jiateng Electromechanical Co ltd
Current assignee: Yancheng Jiateng Electromechanical Co ltd
Priority date: 2021-03-10
Filing date: 2021-03-10
Publication date: 2021-11-02
Anticipated expiration: 2031-03-10

Abstract

The application discloses hot plate for make printed circuit board's laminator, the hot plate includes: a substrate; the heating layer is laid on the substrate and comprises auxiliary heating resistance strips, and the auxiliary heating resistance strips are used for being connected with a power supply to generate heat by utilizing circulating current; the protective cover layer covers the surface of the substrate on which the auxiliary thermal resistance strips are laid and is used for protecting the auxiliary thermal resistance strips; and the insulating layers are arranged between the auxiliary thermal resistance strips and the substrate and between the auxiliary thermal resistance strips and the shield layer and used for forming electric insulation between the auxiliary thermal resistance strips and the substrate and between the auxiliary thermal resistance strips and the shield layer. The application provides a hot plate adopts the resistance strip to heat, guarantees the security through the insulating layer setting, and heating temperature control is convenient simultaneously.

Description

Heating plate

Technical Field

The application relates to the technical field of circuit board manufacturing, in particular to a heating plate for a laminating machine.

Background

Printed circuit boards, generally composed of copper foil, prepreg, and inner layer, may also be called printed circuit boards (pcbs).

The main manufacturing equipment of the printed circuit board is a laminating machine, and the inner core boards and the copper foil are bonded and molded through a semi-cured film at high temperature and high pressure by heating and pressurizing processes when the circuit board is manufactured. The laminator heater block is a plurality of hot plates, and in the space between the hot plate was set up to the multilayer circuit board, hot pressing process of current hot plate adopted the mode of leading to hot oil, and the hot plate has the heating pipeline promptly, leads to high-temperature high-pressure hot oil to the heating pipeline in, heats the hot plate, nevertheless because the risk of revealing exists in the high-temperature high-pressure hot oil, and is very high to equipment safety requirement, moreover, even cut off hot oil supply, still exist hot oil in the heating pipeline, therefore the temperature of hot plate also is not well controlled.

The heating plate adopting electric heating can control the heating heat through the on-off of current, so the temperature control is more convenient. However, the current is controlled, and because a plurality of components of the heating plate are electric conductors, the current is easy to leak, the heating temperature is not easy to control, and the potential safety hazard of electric leakage is also caused.

SUMMERY OF THE UTILITY MODEL

To the shortcomings of the technology, the heating plate with convenient and safe heating temperature control is provided.

The technical scheme adopted by the application for solving the technical problem is as follows:

a heater plate for a laminator for manufacturing printed circuit boards, the heater plate comprising:

a substrate;

the heating layer is laid on the substrate and comprises auxiliary heating resistance strips, and the auxiliary heating resistance strips are used for being connected with a power supply to generate heat by utilizing circulating current;

the protective cover layer covers the surface of the substrate on which the auxiliary thermal resistance strips are laid and is used for protecting the auxiliary thermal resistance strips;

and the insulating layers are arranged between the auxiliary thermal resistance strips and the substrate and between the auxiliary thermal resistance strips and the shield layer and are used for forming electric insulation between the auxiliary thermal resistance strips and the substrate and the shield layer.

In one embodiment, the insulating layer includes an insulating structure wrapped around the auxiliary thermal resistance strip.

In one embodiment, the insulating structure comprises an insulating material for forming electrical insulation.

In one embodiment, the insulating material comprises an alumina material.

In one embodiment, the insulating structure includes an insulating ceramic sintered on the surface of the auxiliary thermal resistance strip.

In one embodiment, the insulating layer further includes a first insulating coating layer disposed on the substrate surface, and a second insulating coating layer disposed on a surface of the shield layer facing the heating layer.

In one embodiment, the first insulating coating or the second insulating coating is an aluminum oxide coating.

In one embodiment, the auxiliary thermal resistance strip is a continuous strip, and the insulating structure and the auxiliary thermal resistance strip are integrated.

In one embodiment, the substrate is an aluminum substrate.

Compared with the prior art, the application has the beneficial effects that: the application provides a hot plate, the adoption is assisted the thermal resistance strip and is heated, realizes the heating through the electric current of circulation, and temperature control is convenient, and assists and set up the insulating layer between thermal resistance strip and adjacent base plate and the guard shield layer, and the security is high, assists the more even unanimity of thermal resistance strip electric current fuel factor.

Drawings

FIG. 1 is a schematic perspective exploded view of a heating plate according to the present application;

FIG. 2 is a schematic cross-sectional view of the heating plate shown in FIG. 1;

FIG. 3 is a schematic top view of a heating layer of a heating plate in another embodiment of the present application.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying the present application are described in detail below with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the application and are not limiting of the application. It should be further noted that, for the convenience of description, only some of the structures related to the present application are shown in the drawings, not all of the structures. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "comprising" and "having," as well as any variations thereof, in this application are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The present application will now be described in further detail with reference to the accompanying drawings, whereby one skilled in the art can, with reference to the description, make an implementation.

As shown in fig. 1 and 2, the present application provides a heating plate 100 for a laminator for manufacturing printed circuit boards. In an embodiment of the present application, the heating plate 100 includes a shield layer (10, 14), a heating layer (11, 13), and a substrate 12. Wherein, the heating layers (11, 13) are laid on the plate surface of the base plate 12, the shielding layers (10, 14) are arranged on the outermost layer of the heating plate 100 and cover the surface of the base plate on which the heating layers (11, 13) are laid for protecting the heating layers (11, 13). After the heating plate 100 is assembled, the heating layers (11, 13) are disposed between the base plate 12 and the shield layer 10. Wherein, the heating layers (11, 13) are electric conductors, are connected with a power supply and can generate heat by utilizing the heat effect of current.

Referring to fig. 3, the heating layer 11 includes an auxiliary thermal resistance strip 111, two ends of the auxiliary thermal resistance strip 111 are connected to a power supply, and after the power supply is turned on, a current flows in the auxiliary thermal resistance strip 111, and a current thermal effect causes the auxiliary thermal resistance strip 111 to generate heat, so that the temperature of the heating plate 100 rises.

Further, because it is the resistance conductor to assist hot resistance strip 111, utilize the electric current of circulation to generate heat, in order to avoid the electric leakage, still be provided with insulating layer 22 between zone of heating and adjacent base plate and the guard shield layer to form electrical insulation and avoid taking place electric leakage or string electricity between zone of heating and the adjacent layer effectively, thereby reduced the inhomogeneous risk of heating temperature that the electric leakage leads to. Specifically, the first heater layer 11 is insulated from the first shield layer 10, the first heater layer 11 is also insulated from the substrate 12, the second heater layer 13 is insulated from the substrate 12, and the second heater layer 13 is insulated from the second shield layer 14. The insulating layer 22 includes an insulating structure wrapped around the outer circumference of the auxiliary heat resistor strip 111, that is, the surface of the auxiliary heat resistor strip 111 is covered with the insulating structure, so that the auxiliary heat resistor strip 111 is insulated from the outside. In one embodiment, the insulating material comprises an insulating ceramic sintered to the outer periphery of the secondary thermistor stripe 111. In another embodiment, the insulating structure includes an insulating material disposed on the surface of the auxiliary resistive heating element 111, and the insulating material may be an aluminum oxide material.

In order to further enhance the reliability of insulation, in the case that the auxiliary thermal resistance strips 111 have an insulation structure, insulation protection can be simultaneously arranged on the substrate 12 and the

shield layers

10 and 14, so that two layers of insulation protection are formed, and the safety is improved. The insulating layer 22 further comprises a first insulating coating disposed on the surface of the substrate 12 and a second insulating coating disposed on the surface of the

shield layers

10, 14 facing the heating layer. That is to say. Preferably, the first insulating coating and/or the second insulating coating is an alumina coating. The

shield layers

10, 14 may be made of an insulating material, thereby forming two layers of insulation protection, and improving the safety and reliability of the insulation protection. Since the first and

second shielding layers

10, 14 may be identical in structure and material, only one of them will be described in detail herein. Likewise, only one of the first heating layer 11 or the second heating layer 13 is described herein.

In one embodiment, the number of heating layers is one, and the heating plate includes a base plate 12, a shield layer 10, and a heating layer 11 disposed between the base plate 12 and the shield layer 10. In a specific implementation scenario applied to a laminating machine, the number of the heating plates is at least two, the two heating plates are stacked on top of each other, and a multilayer core board for manufacturing a circuit board is sandwiched between the two heating plates, wherein the substrate 12 of the heating plates is located at the outer side, the shield layer 10 faces the multilayer core board, and the multilayer core board is heated by the heating layer 11.

In another embodiment, the heating plate 100 may also comprise 2 heating layers, namely a first heating layer 11 and a second heating layer 13, and correspondingly the number of shielding layers (10, 14) is also two, in particular a first shielding layer 10 and a second shielding layer 14. In this embodiment, the heating plate 100 includes, in order, a first shield layer 10, a first heating layer 11, a base plate 12, a second heating layer 13, and a second shield layer 14. The upper and lower surfaces of the heating plate 100 provided in this embodiment can both be used for heating, and can be used as an intermediate plate, and is disposed between the upper and lower heating plates, and two gaps for sandwiching the multilayer core plate are formed between the two adjacent heating plates, and the number of the heating plates disposed in the center may be 1, or may be multiple. The heating plate of the double heating layers that this embodiment provided can be used with the combination of the heating plate of the single heating layer that above-mentioned embodiment provided, and the heating plate setting of single heating layer is at the upper and lower both ends of heating plate stack, and the heating plate setting of double heating layer is in the middle, presss from both sides between the adjacent heating plate and establishes the multilayer core, and every multilayer core carries out the heating of upper and lower two sides by two adjacent heating plates.

The auxiliary thermal resistance strips 11 are configured to be laid on the substrate 12 in a predetermined shape, and the resistance distribution density of the auxiliary thermal resistance strips 11 located in the central region of the substrate 12 is smaller than the resistance distribution density of the auxiliary thermal resistance strips 111 located in the peripheral region of the substrate 12. With the arrangement, when the current magnitude is consistent, the average heat generated by the auxiliary thermal resistance strips 111 in the middle area per unit area is lower than the average heat generated by the auxiliary thermal resistance strips 111 in the peripheral area per unit area, so that the condition that the temperature is lower than that in the middle area due to more heat exchange between the peripheral area of the heating plate and the surrounding environment can be balanced, and the uniformity of the temperature of the heating plate is improved. On the contrary, if the auxiliary thermal resistance strips are uniformly distributed on the substrate 12, under the condition of equal heating heat, the heat exchange between the peripheral area of the substrate 12 and the surrounding environment is more active, the heat dissipation of the substrate 12 in the central area is slower, which leads to the temperature rise in the peripheral area and the temperature in the peripheral area being lower than that in the central area, resulting in the temperature non-uniformity of the heating plate 100, and the quality of the produced printed circuit board is poor or even scrapped. Here, the resistance distribution density is to be understood as a total resistance value per unit area of the substrate plate surface, that is, the resistance distribution density is equal to a resistance value of the corresponding region/an area of the corresponding region. It can be understood that the larger the distribution density of the resistance, the more the heating value of the heating effect of the current is increased by the same current.

For convenience of manufacturing and temperature control, in the present embodiment, the auxiliary thermal resistance strips 111 of the heating layer 11 are continuous strip conductors, two ends of the auxiliary thermal resistance strips 111 are used for connecting a power supply, and after the power supply is connected, the current at any position of the auxiliary thermal resistance strips 111 is the same.

The application provides a hot plate, through the supplementary hot resistance strip 111 of predetermineeing the shape trend, the control is located the heating heat in the base plate 12 different regions to the temperature that the balance leads to because the thermal radiation of different regions is inhomogeneous, can improve the temperature uniformity of hot plate, guarantees printed circuit board's production quality and yield.

How the heating plate processes the printed circuit board will be described below. The printed circuit board is mainly characterized in that copper foils, semi-cured films, inner layers and other core boards are laid and stacked in sequence, a layer of semi-cured film is arranged between adjacent copper foils, and the semi-cured film is subjected to phase change under the action of temperature, so that multiple layers of copper foils are bonded together. The heating plate 100 includes at least two layers of core boards to be pressed, and a plurality of layers of core boards are stacked on the heating plate, and a plurality of layers of core boards are laid between adjacent heating plates, so that a plurality of printed circuit boards can be pressed by one-time high-temperature pressurization.

After the heating and pressing are finished, the temperature is reduced as fast as possible, so that the printed circuit board is convenient to disassemble. In an embodiment, the substrate 12 is further provided with a cooling structure for rapidly cooling the heating plate 100. The cooling structure includes a pipe 122, and particularly, the pipe 122 is formed by the substrate 12. In fig. 1 and 2, only one of the pipes is designated by reference numeral 122 for simplicity of illustration. The pipe 122 may contain cooling water or cooling oil, by which the adjacent first and second heating layers 11 and 13 are effectively cooled. Since the basic peripheral area is in contact with the external environment, the heat dissipation is fast and the temperature reduction is fast, while the central area is in weaker exchange with the external environment and the temperature reduction is slow, in order to balance the uneven heat dissipation. Preferably, the number of the pipes in the central area of the pipe 122 in the substrate 12 is greater than that in the peripheral area, so as to accelerate the heat dissipation of the heating plate 100 in the central area, make the temperature of the heating plate uniform throughout during the cooling process, and prevent the quality problem of the printed circuit board caused by the non-uniform temperature throughout the substrate during the cooling process. Preferably, the pipe 122 is formed in the base plate 12, and the pipe 122 may be separately provided. The substrate 12 is made of aluminum, and the aluminum material is effective for heat dissipation and is lightweight.

With continued reference to fig. 3, the first heating layer 11 includes a positive electrode 114 and a negative electrode 112, and the auxiliary thermal resistance strip 111 has one end connected to the positive electrode 114 and the other end connected to the negative electrode 112. In a specific application process, the positive electrode 114 and the negative electrode 112 are powered on, and current flows in the auxiliary thermal resistance strip 111 to generate heat due to resistance thermal effect to generate heat energy. The type of power supply may be a dc power supply or an ac power supply, preferably a dc power supply. When the auxiliary thermal resistance strip 111 is energized, thermal energy is generated. The energization control manner of the auxiliary thermal resistance strip 111 may specifically be to change the magnitude of the current value or the voltage value of the energization, or to control the on-off time period of the energization. The material of the auxiliary thermal resistance strip 111 may be a material with a high thermal resistance value, such as iron, steel, chromium, manganese, ceramic, etc.

In the exemplary embodiment shown in fig. 3, the spacing between the auxiliary thermal resistance strips 111 of the predetermined shape running in the central region of the substrate 12 is greater than the spacing between the auxiliary thermal resistance strips 111 of the predetermined shape running in the peripheral region of the heating layer 11. In this embodiment, the auxiliary thermal resistance strips 111 have uniformly distributed resistances, wherein uniformly distributed resistances are understood to mean that the resistance values of the auxiliary thermal resistance strips 111 per unit length are the same, and in a specific embodiment, the cross-sectional areas of the auxiliary thermal resistance strips 111 are uniform throughout. The peripheral region and the central region of the substrate are understood as being located at two end portions in the length direction (width) along an extending direction of the substrate, such as the length direction (width direction), and the central portion of the two end portions is the central region, and the peripheral region and the central region are sequentially arranged along the length direction. If the entire area of the heating layer is set to 100%, the ratio of the central area ranges from 30% to 60%, and the ratio of the peripheral areas on the left and right sides of the central area ranges from 35% to 20%, respectively. In this embodiment, the predetermined shape of the auxiliary thermal resistance strips 111 is a serpentine shape, which may also be referred to as a "bow" shape. Specifically, referring to fig. 3, the radiation resistor strips 111 are substantially parallel strip-shaped strips connected end to end, and the connection portion between adjacent strip-shaped strips is in an arc shape, so that the temperature concentration caused by the sharp transition of the strip-shaped strips is reduced. And the distances between the adjacent strip belts are different, and the distance between the middle area is larger than the distance between the strip belts at the two end areas.

In this embodiment, specifically, the strip-shaped bands are arranged parallel to two opposite sides of the heating plate, the distance between the strip-shaped bands changes in an increasing and decreasing manner along a direction perpendicular to the strip-shaped bands, the decreasing and decreasing change amplitudes are the same, the strip-shaped bands presenting the increasing change and the strip-shaped bands presenting the decreasing change are symmetrical to each other, and the selectable increasing and decreasing amplitudes are 0.2, 0.3cm, 0.4cm, 0.5cm and 0.8 cm. When the incremental distance is selected to be 0.5cm, the temperature change at each position of the heating plate tends to be consistent, and the temperature of each area is more uniform.

In another embodiment, the resistance is not uniform throughout the auxiliary thermal resistance strips 111, and the cross-sectional area of the auxiliary thermal resistance strips located in the central region of the substrate 12 is larger than the cross-sectional area of the auxiliary thermal resistance strips 111 located in the peripheral region of the substrate 12. It can be understood that the thicker the auxiliary thermal resistance strips 111, the lower the resistance thereof, and the lower the current heating effect, the thicker the central region of the resistance strips 111 is set to be than the peripheral region of the auxiliary thermal resistance strips 111, so that the same current generates less heat in the central region, and the uneven temperature of the heating plate caused by the uneven heat radiation in the peripheral region and the central region of the heating plate can be balanced. By setting the cross sectional areas of the auxiliary thermal resistance strips 111 in different areas to be different, the resistance value of the auxiliary thermal resistance strip in the middle area is controlled to be smaller than that of the auxiliary thermal resistance strip 111 in the peripheral area, so that the heating heat energy of the middle area is effectively controlled to be smaller than that of the peripheral area.

The substrate 12 is provided with an installation groove having a shape consistent with the preset shape of the auxiliary thermal resistance strip 111, the auxiliary thermal resistance strip 111 is embedded in the installation groove, and the protection cover 10 (or 14) is covered on the auxiliary thermal resistance strip 111. The processing and manufacturing are convenient. The auxiliary heat resistor strips 111 have a uniform size in the thickness direction of the heating plate 100, and the width of the auxiliary heat resistor strips 111 in the central region of the substrate is greater than the width of the auxiliary heat resistor strips 111 in the peripheral region of the substrate 12. Correspondingly, the depth of each mounting groove is consistent, and the width of the mounting groove in the middle area of the substrate 12 is larger than that of the mounting groove in the peripheral area of the substrate 12. Therefore, when the mounting groove is formed in the substrate 12, only the width of the mounting groove (the width of the auxiliary thermal resistance strip) needs to be controlled, and the processing and the manufacturing are convenient.

In other embodiments, the predetermined shape of the auxiliary thermal resistance strips 111 may also be a zigzag shape or a zigzag shape. The auxiliary thermal resistance strips 111 in the zigzag trend are laid in a first circle along the constant distance from the outer contour of the substrate, are roughly wound in a circle but are not closed, are laid in a second circle along the constant distance from the first circle, are laid in the same mode until reaching the middle of the substrate 12, are laid in a circle from the middle of the substrate 12 to the peripheral area until reaching the edge of the substrate, and are convenient to switch on a power supply. The auxiliary thermal resistance strips of each circle are continuous, the distance between the adjacent auxiliary thermal resistance strips is different, and the distance between the auxiliary thermal resistance strips positioned in the middle area is larger than that of the auxiliary thermal resistance strips positioned in the peripheral area. Preferably, the pitches of the auxiliary thermal resistance strips increase in sequence from the outer edge to the middle. In this embodiment, the central region refers to a region within a predetermined distance from the geometric center of the substrate, and the peripheral region refers to a substantially annular region at the peripheral edge of the substrate. The auxiliary heating resistor strips with the square-shaped trend can be laid according to the distance between the substrate and the surrounding environment, and the problems that the temperature of the middle part of the substrate is high and the surrounding temperature is low due to the fact that the peripheral area of the heating plate exchanges heat with the environment more are effectively compensated.

The application provides a heating plate 100's zone of heating 11 (or 13) is for having the supplementary thermal resistance strip 111 of predetermineeing the shape trend, can arrange the supplementary thermal resistance strip trend or move towards interval between according to the size of hot plate adaptability to reduce effectively that the heat that is located the hot plate of middle part region and peripheral zone loses the uneven risk that leads to the temperature inhomogeneous, further improve the heating process hot plate 100 temperature uniformity everywhere.

With continued reference to FIG. 3, the heating plate 100 further includes a temperature measuring unit 113. The temperature measuring unit 113 serves to measure the temperature of the heating plate 100, thereby feeding back the temperature to the main controller 300 of the laminator 500, so that the main controller 300 can form closed-loop control of heating according to the temperature of the heating plate 100.

The heating plate 100 provided in the present application may be used in the manufacture of printed circuit boards, including flexible circuit boards and conventional rigid circuit boards. The total resistance value of the auxiliary thermal resistance strip 111 is 0.1 Ω -10 Ω, preferably 1.5 Ω, 2.5 Ω.

While the embodiments of the present application have been disclosed above, it is not limited to the applications listed in the description and the embodiments, which are fully applicable in a variety of fields suitable for this application, and further modifications will be readily apparent to those skilled in the art, and it is therefore not intended to be limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.

Claims

1. A heater plate for a laminator for manufacturing circuit boards, the heater plate comprising:

a substrate;

2. The heating plate as claimed in claim 1, wherein the insulating layer comprises an insulating structure wrapped around the outer circumference of the auxiliary thermal resistance strip.

3. The heating plate of claim 2, wherein the insulating structure comprises an insulating material for forming an electrical insulation.

4. The heating plate of claim 3, wherein the insulating material comprises an insulating ceramic sintered to the surface of the secondary thermistor strip.

5. The heating plate of claim 3, wherein the insulating material comprises an aluminum oxide material.

6. The heating plate of claim 2, wherein the insulating layer further comprises a first insulating coating disposed on a surface of the substrate, and a second insulating coating disposed on a surface of the shield layer facing the heating layer.

7. The heating plate of claim 6, wherein the first insulating coating or the second insulating coating is an aluminum oxide coating.

8. The heating plate of claim 2 wherein said secondary thermal resistance strip is a continuous elongated strip, said insulating structure being integral with said secondary thermal resistance strip.

9. The heating plate of claim 1, wherein the substrate is an aluminum substrate.