CN113510946B - Carbon fiber composite material molding press - Google Patents

Abstract

The invention discloses a carbon fiber composite material molding press, which comprises: a frame; the lower die is of a groove-shaped structure arranged on the rack and is provided with a process groove with an upward opening, and a heating device is arranged in the lower die; the first conveying mechanism is positioned on the first side of the process tank and used for conveying the carbon fiber layer into the process tank; the second conveying mechanism is positioned on the second side of the process groove and used for conveying the material layer compounded with the carbon fibers into the process groove; the second side and the first side are not the same side of the process groove; the upper die is a movable die and is positioned on the rack right above the lower die, and the driving mechanism is connected with the upper die in an output mode so as to drive the upper die to move. The invention has high efficiency and is easy to ensure the product quality.

Description

Carbon fiber composite material molding press

Technical Field

The invention relates to a carbon fiber composite material molding press.

Background

Carbon fiber has been widely used in aerospace, military, turbine blades, construction, light cylinders and pressure vessels, marine cables and drilling risers, automobiles, medical and sporting goods, etc. due to its excellent properties. In these broad applications, carbon fibers are used primarily as reinforcing fibers in composite materials to reinforce matrices of polymers, metals, and the like.

At present, various carbon fiber composite materials are applied and developed in the fields of aviation, industry, construction and medical treatment. The carbon fiber reinforced PEEK composite material has excellent creep resistance, damp and heat resistance, aging resistance and impact resistance. Therefore, carbon fibers and their composites have developed very rapidly in recent years. At present, the variety of the composite material of the carbon fiber and the thermoplastic resin comprises almost all high-performance engineering materials, forms a multi-variety, multi-functional and multi-level industrial structure, and provides a wide selection range for users, so that the carbon fiber reinforced thermoplastic resin composite material is widely applied in many fields.

At present, relatively large-scale molding equipment is used for manufacturing carbon fiber composite materials, the investment of the molding equipment is large, and when the carbon fiber composite materials are manufactured, the carbon fiber composite materials need to be firstly paved, and paving is mainly completed manually at present. For example: in the process of carrying out mould pressing compounding on the carbon fiber and the polyether-ether-ketone, a film laminating method is mostly adopted. Specifically, a layer of carbon fiber cloth is separated by a layer of polyetheretherketone thin plate, the carbon fiber cloth and the polyetheretherketone thin plate are stacked layer by layer to form an intermediate piece, and then the intermediate piece is sent to a mould pressing device for mould pressing.

Because the number of layers of the layers is positively correlated with the thickness of the finally formed carbon fiber composite material, dozens of layers or even hundreds of layers are generally laid manually and then are transferred to a molding press for molding in a unified way. During mould pressing, due to the fact that heating capacities of heating plates on a mould pressing machine are different, the heating plates are shielded between layers, and the outer edges and the inner heat dissipation capacity are different, the phenomena that the temperatures of two sides close to the heating plates are too high, the middle temperature is low, the temperature of an outer layer is high, the temperature of an inner layer is low are easily caused, and the combination of polyether-ether-ketone and carbon fibers is relatively poor. To overcome the problem of relatively poor bonding strength caused by this phenomenon, it is necessary to adapt the work time long enough to sufficiently heat through the workpiece, and a relatively greater pressure is also required to obtain a better press-fit quality due to the larger number of layers.

Typically, as described in chinese patent document CN209022485U, a carbon fiber molding apparatus suitable for one-time molding is provided, which comprises an upper mold and a lower mold, wherein the upper mold is a movable mold, the lower mold is provided with a groove, the lower mold is provided with a heat transfer oil circulation pipe as a heating device therein, and when in use, stacked intermediate members are placed in the groove, and then the upper mold descends to perform molding. Because the heating device needs to be stable in heating, the heating device which is generally adopted at present is heated by heat conduction oil, the heating mode needs to be matched with a pipeline, and the configuration of the heating device on the movable mould is relatively complex. The stacked intermediate pieces have long heat penetration time and are easy to have defects; moreover, the degree of fusion between the inner layer carbon fiber and the resin is not easy to observe, and a long time is required to ensure heat penetration, which results in relatively low efficiency. In addition, the inner layer bubbles are not easy to overflow in the fusion process, so that defects are easy to occur.

Disclosure of Invention

The invention aims to provide a carbon fiber composite material molding press which is high in efficiency and easy to ensure the product quality.

In an embodiment of the present invention, there is provided a carbon fiber composite molding press whose basic structure includes:

a frame;

the lower die is of a groove-shaped structure arranged on the rack and is provided with a process groove with an upward opening, and a heating device is arranged in the lower die;

the first conveying mechanism is positioned on the first side of the process tank and used for conveying the carbon fiber layer into the process tank;

the second conveying mechanism is positioned on the second side of the process groove and used for conveying the material layer compounded with the carbon fibers into the process groove; the second side and the first side are not the same side of the process groove;

an upper die which is a movable die and is positioned on the machine frame right above the lower die, an

And the output of the driving mechanism is connected with the upper die so as to drive the upper die to move.

Optionally, a shield is provided on the upper die to cover the process tank after the lower die is in place.

Optionally, the shroud is a floating shroud configured to:

the shield is supported on the upper surface of the upper die and has an upward degree of freedom relative to the upper die.

Optionally, the upper mold comprises:

the upper die base is connected with the driving mechanism;

the upper template is aligned with the process groove and is connected with the upper die base through a guide pillar;

the damping sleeve is sleeved on the guide pillar and supported between the upper die base and the upper die plate;

the guide post is fixedly connected with the upper die plate, a through hole is formed in the upper die base, and the guide post is limited by the reverse limiting structure after penetrating through the through hole.

Optionally, the reverse limiting structure is configured to:

the upper end surface of the guide post is provided with a screw hole;

and providing a screw with a screw head diameter larger than the diameter of the through hole, wherein the screw is tightly connected with the screw hole, and the screw head forms the reverse limiting structure.

Optionally, the damping sleeves are four, and correspondingly distributed at four corners of the upper die.

Optionally, a control template is further disposed on the upper surface of the upper mold plate or the lower surface of the upper mold base to form a rigid limit to control the minimum distance between the upper mold plate and the upper mold base.

Optionally, a stretching roller for assisting the stretching is further included, the stretching roller comprising:

the roll shaft is a straight shaft, at least one end of the roll shaft is a holding end, the roll shaft is provided with a working section, and the length of the working section is the same as the width of the process groove;

the barbed nails are arrayed on the working section.

Optionally, the spikes have at least two rows, the row direction is the axial direction of the roller shaft, and the spikes contained in the two rows are parallel to each other.

Optionally, the heating device is configured to: a flow channel for circulating heat conduction oil is arranged in the lower die;

the flow passages are arranged in parallel in one direction of the length or the width of the lower die, and an oil inlet joint header and an oil outlet joint header are respectively arranged at two ends of each flow passage;

correspondingly, the flow directions of the heat conducting oil in the adjacent flow channels are opposite, and the oil inlet header and the oil outlet header at the corresponding ends are correspondingly connected with the corresponding flow channels.

Different from the prior art that the process groove is firstly stacked and then hot-pressed, in the embodiment of the invention, two sides of the process groove of the lower die are respectively provided with a conveying mechanism, one conveying mechanism can be used for conveying a carbon fiber layer, and the other conveying mechanism can be used for conveying a layer compounded with the carbon fiber layer. Meanwhile, shallow gas is easy to overflow, so that bubbles in the composite material are not easy to form. Meanwhile, due to the fact that the number of layers is small, the compounding working hours are easy to control, although several times or even dozens of times of hot pressing are probably needed for the composite material with the target layer thickness, the total working hours are still relatively small, and the quality of the compounded material is relatively stable.

Drawings

FIG. 1 is a schematic view of a main view of a carbon fiber composite molding press according to an embodiment.

Fig. 2 is a schematic view of a structure of a screen roller in one embodiment.

Fig. 3 is a schematic view of a mold structure according to an embodiment.

In the figure: 1. the device comprises a first conveying mechanism, a control cabinet, a column, a guide rod, an upper die base, a lower die, a mesh-stretching roller, a protective cover, a side door, a roller shaft body, a spike nail, a guide sleeve, a fixing plate, a roller shaft body, a roll shaft body, a spike nail, a guide sleeve, a fixing plate, a control template, a process groove, a power cylinder, a guide column, a damping sleeve and an upper die plate, wherein the control cabinet is 2, the column is 3, the guide rod is 4, the upper die base is 5, the lower die is 6, the mesh-stretching roller is 7, the protective cover is 8, the side door is 9, the second conveying mechanism is 10, the diagonal brace is 11, the roller shaft body is 12, the spike nail, the guide sleeve is 14, the fixing plate is 15, the control template is 17, the process groove is 18, the power cylinder is 19, the guide column is 20, the damping sleeve is 21, and the upper die plate is arranged on the upper die plate.

Detailed Description

In the embodiment of the present invention, as seen from fig. 1, the rest of the carbon fiber composite material molding press except for the first conveying mechanism 1, the second conveying mechanism 10, the shield 8 and the mesh roller 7 is relatively similar to the prior art, and an exemplary structure of the upper mold, which is also a structural part distinguished from the prior art, is further illustrated in fig. 3, and a detailed description is mainly made below for those parts distinguished from the prior art, and the same parts as the prior art are briefly described.

The frame provides a foundation for mounting other components as a basic framework of the carbon fiber composite material molding press, and is also a matrix of mechanical equipment in the mechanical field, which is not described in detail and should be clearly understood by those skilled in the art.

If the frame is the base body, the mold is the core of a carbon fiber composite molding press, and includes a lower mold 6 and an upper mold, where the lower mold 6 is typically statically disposed in the carbon fiber composite molding press or fixedly mounted on the frame, and the upper mold is typically a movable mold that moves to effect the closing and opening of the mold.

After the upper die and the lower die 6 are closed, a die cavity is formed, an intermediate piece to be compounded is arranged in the die cavity, and after the die is closed, the intermediate piece needs to be heated, so that materials (matrix materials such as resin, metal, ceramic and the like) compounded with carbon fibers are in a relatively softened or molten or semi-molten state (the melting point of carbon is much higher than that of most materials), and the carbon fibers are embedded in the intermediate piece.

The upper die is used as a movable die and is aligned with the lower die 6 in the vertical direction, correspondingly, the upper die is positioned on a machine frame right above the lower die 6, and in order to realize die assembly or die opening, a driving mechanism is configured to be in output connection with the upper die so as to drive the upper die to move, and thus the die assembly or die opening is realized.

The mold cavity is mainly provided by a lower mold 6, specifically, the lower mold 6 is of a groove-shaped structure and is provided with a process groove 17 with an upward opening, a middle piece is placed into the process groove 17, then mold closing is carried out, and during mold closing, a certain pressing force needs to be applied to an upper mold, so that carbon fibers are compounded into the upper mold under the condition that a material compounded with the carbon fibers does not need to be melted.

It is common knowledge in the art that different materials that are carbon fiber composites will heat at different temperatures. However, the temperature needs to be relatively stable, so the heating is mainly fluid heating, mainly using heat transfer oil for heating, and controlling the highest temperature of the heat transfer oil can avoid temperature over-tolerance.

Correspondingly, a heating device is arranged in the lower die 6, the heating device is specifically configured to arrange a flow channel for circulating heat conducting oil in the lower die 6, and the same type of heat exchanger is used, and the highest heating temperature can be controlled by controlling the temperature of the heat conducting oil.

In a preferred embodiment, the flow channels are arranged in a relatively reasonable arrangement, which is as follows:

the flow channels are arranged in parallel in one direction of the length or the width of the lower die to carry out uniform heating, and in consideration of gradual temperature reduction of fluid in the flow channel in the flowing process, in order to improve the relative uniformity of temperature distribution, an oil inlet connecting header and an oil outlet connecting header are respectively arranged at two ends of each flow channel.

And then, the heat conduction oil flow direction in the adjacent flow channels is opposite, and the oil inlet header and the oil outlet header at the corresponding ends are correspondingly connected with the corresponding flow channels. In this structure, in the same lower mold 6, some runners flow in one direction, and the other runner flows in the opposite direction, i.e. there are two sets of runners, based on this distribution, relatively better temperature distribution can be obtained, and relative uniformity of heating during compounding can be ensured.

In some embodiments, an electric heating device may also be used, which has the disadvantage that even if the distribution of the resistance wires is relatively uniform, it is not ensured that the lower mold 6 is uniformly heated, in that the resistance wires in principle have no upper limit for high temperature, as long as they do not melt.

However, electrical heating may be an option if there is better closed loop control of the temperature.

Similarly, the effect of closed-loop control of electrical heating is limited by the location of the temperature sampling element due to the relative non-uniformity of heating, and in contrast, in the embodiment of the present invention, the aforementioned solution using conduction oil heating is preferred.

One configuration that differs from the prior art is that in the embodiment of the present invention, two conveying mechanisms are provided for the carbon fiber composite material molding press, such as the first conveying mechanism 1 and the second conveying mechanism 10 shown in fig. 1, and in fig. 1, the first conveying mechanism 1 and the second conveying mechanism 10 are respectively located at two opposite sides of the process tank 17, and it is obvious that since the process tank 17 is a rectangular tank in general, stacking of materials does not necessarily require that the first conveying mechanism 1 and the second conveying mechanism 10 are opposite, but only that the two conveying mechanisms are different in side.

One of the transport devices is used to transport the carbon fibre layers, for example the first transport device 1, and the other transport device is used to transport the layers of material combined with carbon fibres, for example the second transport device 10.

As is known, in general, the intermediate member of the stack is usually a layer of carbon fiber, a layer of material combined with carbon fiber, and as mentioned above, a layer of carbon fiber and a layer of material combined with carbon fiber are referred to as a unit, and after stacking one unit or not more than 10 units, thermal combination can be performed. By the structure, the workload of workers can be reduced, and the interlayer is relatively less in number, so that the heat is easy to penetrate through and the lamination is easy.

Compared with the traditional composite process, in the embodiment that a workpiece is formed by multiple times of composite, the heat dissipation has stricter requirements, and for this reason, the upper die is provided with the protective cover 8 to cover the process groove 17 after descending in place, so that the heat utilization rate can be improved.

For the same workpiece, the composite working stroke of the upper die is different every time, and according to the characteristic that the workpiece is gradually thickened, the working stroke of the upper die is gradually reduced aiming at the forming process of the same workpiece. Correspondingly, the shield 8 is a floating shield, configured in particular to:

the protective cover 8 is supported on the upper surface of the upper die and can move upwards along with the upper die, and the protective cover 8 has the freedom degree of moving upwards relative to the upper die, in other words, if the protective cover 8 and the lower die generate movement interference in the descending process of the upper die, the protective cover cannot further descend, but if the upper die is not moved in place, the protective cover can still continue to descend, and the position of the protective cover 8 can be kept still. When the upper die is reset, the upper die first moves relative to the shield 8, and the shield 8 is reset along with the upper die until the upper part of the shield 8 can be supported by the upper die.

The upper die also takes into account the gradual change of the working stroke in the preferred embodiment, according to which the upper die has the following configuration:

the upper die base 5 is connected with the driving mechanism;

the upper die plate 21 is aligned with the process groove 17 and is connected with the upper die holder 5 through a guide post 19, the upper die plate 21 is correspondingly provided with a guide hole matched with the guide post 19, and in some embodiments, a wear-resistant sleeve such as a bronze sleeve can be embedded in the guide hole to improve the wear resistance;

the damping sleeve 20 is sleeved on the guide pillar 19 and supported between the upper die holder 5 and the upper die plate 21, the damping sleeve 20 can be a rubber sleeve or a cylindrical spring, and obviously, under the condition that the natural length of the damping sleeve 20 is the same, the smaller the distance between the upper die holder 5 and the lower die plate 21 is, the larger the pressure of the lower die plate 21 on a workpiece is; the positive correlation exactly matches with the feature of the workpiece gradually thickened, specifically, in the case that the working stroke of the upper die holder 5 is determined, when the workpiece is thickened, the distance between the upper die plate 21 and the upper die holder 5 is relatively smaller, so that a larger pressure can be provided, and after the workpiece is thickened, the workpiece has a higher requirement on the pressure, and the positive correlation is one of the innovations of the invention.

The guide post 19 is fixedly connected with the upper template 21, the fixed connection can be welding or threaded connection, specifically, a blind hole is formed in the upper template 21, the blind hole is a threaded hole, the lower end of the guide post 19 is provided with threads, and the guide post is in threaded connection with the upper template 21.

The upper die base 5 is provided with a via hole, the guide pillar 19 penetrates through the via hole and is limited by a reverse limiting structure, namely the guide pillar 19 is limited by the reverse microstructure and cannot fall off, the lower die plate 21 can be hung, and meanwhile, when the upper die plate 21 is stopped by the reaction force of a workpiece, the guide pillar 19 moves upwards and cannot generate motion interference with the upper die base 5.

With regard to the reverse limiting structure, in a preferred embodiment, it is configured to:

the upper end surface of the guide post 19 is provided with a screw hole;

the screw with the nail head diameter larger than the diameter of the through hole is provided, the screw is tightly connected with the screw hole, the nail head forms the reverse limiting structure, the screw connection is convenient to detach, and the maintenance is convenient.

In order to ensure the relative stability of the operation of the lower template 21, four damping sleeves 20 are provided, which are correspondingly arranged at the four corners of the upper die, and correspondingly, four guide posts 19 are provided, which correspond to the damping sleeves 20 one by one.

In order to avoid over-travel, a control template 16 is further disposed on the upper surface of the upper template 21 or the lower surface of the upper mold base 5 to form a rigid limit to control the minimum distance between the upper template 21 and the upper mold base 5, and the control template 16 is equivalent to a baffle. It will be appreciated that since the thickness of the workpiece after final forming is set, but the stacked intermediate members are relatively bulky and have a relatively large thickness, the pressure provided by the damping sleeve 20 may not be sufficient, and the rigid control template 16 may provide direct transmission to allow the upper template 21 to have a larger pressure after simultaneously making contact with the upper template 21 and the upper die base 5.

With respect to the manual stacking of the intermediate members, the laying quality of the carbon fiber layer delivered by the first conveying mechanism 1 is not good, and the layer of material combined with the carbon fiber layer delivered by the second conveying mechanism 10 has a certain rigidity, which can ensure the laying quality, and with respect to the carbon fiber layer, in a preferred embodiment, the carbon fiber layer further includes a stretching roller 7 for assisting the stretching, the stretching roller is manually controlled, and as shown in fig. 2, the stretching roller includes:

a roll shaft, such as the roll shaft body 12 shown in fig. 2, which can be seen as a straight shaft in the drawing and has at least one end being a holding end for facilitating the holding of a worker, wherein the roll shaft 12 has a working section, and the length of the working section is the same as the width of the process groove 17;

and the barbed nails 13 are arrayed on the working section.

In the working process, when piling up, the supplementary first conveying mechanism 1 material loading of workman mainly is that the workman holds two net rollers 7, hangs the both ends of carbon fiber layer and opens the net, piles up the back that finishes, and the workman withdraws from net roller 7, then carries out the hot pressing.

In the configuration shown in fig. 2, the spikes 13 are arranged in at least two rows, the row direction is the axial direction of the roller shaft, and the spikes 13 included in the two rows are parallel to each other, so as to facilitate the spreading of the net.

Claims (9)

1. The carbon fiber composite molding press is characterized by comprising:

a frame;

the lower die is of a groove-shaped structure arranged on the rack and is provided with a process groove with an upward opening, and a heating device is arranged in the lower die;

the first conveying mechanism is positioned on the first side of the process tank and used for conveying the carbon fiber layer into the process tank;

the second conveying mechanism is positioned on the second side of the process groove and used for conveying the material layer compounded with the carbon fibers into the process groove; the second side and the first side are not the same side of the process tank;

an upper die which is a movable die and is positioned on the machine frame right above the lower die, an

The output of the driving mechanism is connected with the upper die so as to drive the upper die to move;

wherein the heating device is configured to: a flow channel for circulating heat conducting oil is arranged in the lower die;

the flow channels are arranged in parallel in one direction of the length or the width of the lower die, and an oil inlet connecting header and an oil outlet connecting header are respectively arranged at two ends of each flow channel;

correspondingly, the heat conduction oil flow direction in the adjacent flow channels is opposite, and the oil inlet header and the oil outlet header at the corresponding ends are correspondingly connected with the corresponding flow channels.

2. The carbon fiber composite molding press as claimed in claim 1, wherein the upper mold is provided with a shield to cover the process tank after running down into position.

3. The carbon fiber composite die press as claimed in claim 2, wherein the shroud is a floating shroud configured to:

the shield is supported on the upper surface of the upper die and has an upward degree of freedom relative to the upper die.

4. The carbon fiber composite molding press of claim 1, wherein the upper mold comprises:

the upper die base is connected with the driving mechanism;

the upper template is aligned with the process groove and is connected with the upper die base through a guide post;

the damping sleeve is sleeved on the guide pillar and supported between the upper die holder and the upper die plate;

the guide post is fixedly connected with the upper die plate, a through hole is formed in the upper die base, and the guide post is limited by the reverse limiting structure after penetrating through the through hole.

5. The carbon fiber composite die press as claimed in claim 4, wherein the reverse limiting structure is configured to:

the upper end surface of the guide post is provided with a screw hole;

and providing a screw with a screw head diameter larger than the diameter of the through hole, wherein the screw is tightly connected with the screw hole, and the screw head forms the reverse limiting structure.

6. The carbon fiber composite molding press as claimed in claim 4, wherein said damping sleeves are four, respectively, spaced at the four corners of the upper mold.

7. The carbon fiber composite molding press of any one of claims 4 to 6, wherein a control template is further provided on the upper surface of the upper mold plate or the lower surface of the upper mold base to form a rigid limit to control the minimum distance between the upper mold plate and the upper mold base.

8. The carbon fiber composite die press as claimed in claim 1, further comprising a screen roller for assisting screening, the screen roller comprising:

the roll shaft is a straight shaft, at least one end of the roll shaft is a holding end, the roll shaft is provided with a working section, and the length of the working section is the same as the width of the process groove;

the barbed nails are arrayed on the working section.

9. The carbon fiber composite molding press as claimed in claim 8, wherein the spikes have at least two rows, the row being in the axial direction of the roller, the spikes contained in the two rows being parallel to each other.

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