JP2020094866A - Detector for pressure and temperature in mould - Google Patents

Abstract

To provide a detector for pressure and temperature in a mould.SOLUTION: A detector for pressure and temperature in a mould in the present invention comprises a frame body, a pedestal, a pressing lever, a strain structure, a strain gauge, a temperature detection element, and a processing unit. The frame body is provided within a metal mould, brought into communication with a mould hole, and includes a passage and a housing space. The pedestal is provided on a bottom surface of the frame body and includes a flat surface on a top thereof. The pressing lever is provided in the housing space and includes a front end that extends to the passage and is exposed in the mould hole. The strain structure is provided between the flat surface and a rear end of the pressing lever, and fixedly positioned on the flat surface. The strain gauge is provided in the strain structure, measures an amount of deformation of the strain structure subjected to a mould hole pressure, and is used for converting the amount into deformation information. The temperature detection element is provided in the pressing lever, measures the temperature of the pressing lever and is used for converting the temperature into pressing lever temperature information. The processing unit is electrically connected to the strain gauge and the temperature detection element, respectively, and acquires the deformation information and the pressing lever temperature information.SELECTED DRAWING: Figure 7

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure and temperature detection device in a mold, and more particularly, to a detection device that immediately measures changes in the temperature and pressure of a mold at the same position in a mold cavity.

Injection molding is a high-speed molding method that does not require cutting, and processes such as injection molding and pressure casting have high manufacturing efficiency, are economical, have high dimensional accuracy, and have high compatibility, so they are large-scale. It is widely applied in industry and is developing rapidly. Pressure casting has become a main forming method for light metals such as aluminum, magnesium, and zinc, and is applied to the production of large-sized complex thin-walled frame members.
Pressure casting parts are important components for products in fields such as automobiles, sports equipment, electronics industry, and aerospace industry. Especially, in the automobile industry, pressure casting technology is a major field to which the pressure casting technology is applied. Account for over 70%. With the rapid development of industries such as automobiles, motorcycles, internal combustion engines, electronic communications, instruments, home appliances, and hardware, the function and application fields of pressure casting members continue to expand. Urging.

However, conventional injection molded products are designed and manufactured based on actual manufacturing experience, and are operated by combining CAD and CAE. Therefore, the pressure curve in the mold on the simulation and the actual mold There is a considerable difference with the pressure curve of. As shown in FIG. 1, most of the problems that appear in the actual manufacturing process rely on actual experience to analyze and take measures.

The conventional injection molding industry faces at least the following problems.
1. The installation quality and deterioration status of the process equipment do not match, and the correction efficiency of the process parameters is too low.
2. The quality of the finished product cannot be monitored immediately and the sample must be inspected after manufacturing.
3. Small lot manufacturing costs are too high to achieve inventory control optimization.

In conventional Patent Document 1, for example, an extruding pin with pressure sensor (Ejector pin with pressure sensor) is disclosed. The extruding pin includes a pin for extruding a workpiece and a sleeve for smoothly covering the pin. Have. The end of the pin corresponds to the mold cavity through the opening surface of the end of the guide portion. The pocket is defined by the stepped portion at the lower end of the sleeve portion. A strain-forming portion having a U-shaped cross section located at the pin base is loaded in the pocket. A strain sensor is attached to the lower surface of the cross beam in the strain forming portion. The pressure of the injected resin is applied to the end of the pin, and the downward load applied to the pin causes the cross beam to bend downwards.
The detection element having such a structure is mounted outside the mold. This belongs to the indirect measurement method, and the position where the pin abuts against the cross beam must be directly aligned with the center of the cross beam. Otherwise, the abutted position is deviated from the center point, and the distortion rate of the deformation data is greatly increased.

US Patent Application No. 6345974B1

The present inventor thought that the above-mentioned drawbacks can be ameliorated, and as a result of earnest studies, the inventors have arrived at the proposal of the present invention which effectively ameliorate the above-mentioned problems by rational design.

The present invention has been made to solve the problems of the above-mentioned conventional techniques. That is, the object of the present invention is a detection device capable of directly measuring the pressure in the mold and the temperature in the mold in the injection process in the mold, and the strain gauge and the temperature detecting element are retained in the strain structure of the non-pressure transmission path. And a strain gauge and a temperature detecting element are installed in the detecting device.

The present invention for solving the above-mentioned problems is a frame body which is internally provided in a mold and whose ceiling surface is exposed from a mold hole of the mold, wherein the ceiling surface is provided with a passage and is concave. It has an open end that communicates with the accommodation space in the body, and has an open end on the bottom surface of the frame body that communicates with the accommodation space, and is installed on the bottom surface of the frame body to close the accommodation space and have a flat surface on the top. A pedestal having a through hole in the center, and a front end that is installed in the accommodation space and extends into the passage and is exposed in the mold cavity, and the pressure of the mold cavity is transmitted from the front end. After that, the pressure lever is displaced axially in the passage, and the strain structure is installed between the flat surface and the pressure lever, and the pressure transmitted by the displacement of the pressure lever is Converting to the deformation amount of the strain structure, installed in the strain structure, at least one strain gauge for measuring the deformation amount of the strain structure and converting it into deformation information, and installed in the pressing lever, At least one temperature detecting element for measuring the immediate temperature of the pressing lever and converting it into pressing lever temperature information, and electrically connected to the strain gauge and the temperature detecting element, respectively, the deformation information and the pressing lever. A pressure and temperature detection device in a mold, comprising: a processing unit for acquiring temperature information.

In a preferred embodiment of the present invention, the ceiling surface of the frame is substantially horizontal to the mold cavity surface, and at the time of initial installation, when the pressure lever is not receiving pressure, an end surface of a front end of the pressure lever and The ceiling surface maintains flatness.

In a preferred embodiment of the present invention, the pressing lever further includes a lever body connected to the front end and a rear end flat surface connected to the lever body and facing the front end. The rear end flat surface is located in the accommodation space and abuts against the strained structure, and the rear end flat surface has a diameter larger than a diameter of the passage. An elastic member is covered on the lever body, and both ends of the elastic member are respectively brought close to the rear end flat surface and the end surface of the passage from the accommodation space to limit a movement limit thereof. The elastic member is used to return the pressing lever to the original position when the pressing lever releases an external force and causes a displacement in the axial direction.

In a preferred embodiment of the present invention, these temperature detecting elements are installed in the pressure lever and the strain structure, and in order to measure the pressure lever temperature information and the instantaneous temperature of the strain structure, respectively, and to feed them back to the processing unit. Used.

In a preferred embodiment of the present invention, the strained structure includes a push plate portion, a seat plate portion, and a pair of support beams whose both ends are connected to the push plate portion and the seat plate portion, respectively. The seat plate portion is located on the flat surface, the push plate portion is adjacent to the rear end of the push lever, and the pair of support beams are installed parallel to the moving direction of the push lever. The beam bodies of the pair of support beams are respectively bent and deformed in a direction facing the other support beams after receiving the pressure applied by the pressing plate portion. At least one strain gauge is installed on one beam body of the pair of support beams.

In a preferred embodiment of the present invention, the support beams may be made of a material such as metal or ceramic, and may be made of plastic when the temperature is low. In principle, these supporting beams may be made of any material that does not cause permanent deformation in the amount of deformation in the accommodation space.

In a preferred embodiment of the present invention, the seat plate portion is located in a recessed positioning slot formed at a center position of the seat plate portion of the flat surface, and the corresponding flat surface is fitted with the positioning slot. Parts are provided.

In a preferred embodiment of the present invention, the central portion of the end face of the rear end of the pressing lever so that the transmission lines of power and signals of the strain gauges and the temperature detecting elements penetrate to the outside of the frame and the pedestal. A blind hole is provided in the center, and a through hole is provided in the center of the strained structure and the center of the pedestal.

In a preferred embodiment of the present invention, the processing unit obtains the deformation information of the strain structure and the pressure lever temperature information, respectively, and evaluates the influence on the deformation amount generated by the material of the strain structure at the temperature of the pressure lever. , Let the actual pressure value of the mold cavity be further estimated.

In a preferred embodiment of the present invention, the processing unit obtains the deformation information of the strained structure at the same time, the immediate temperature of the strained structure, and the pressing lever temperature information, and the deformation amount generated by the material of the strained structure. After converting the effect of the immediate temperature of the strained structure, the actual pressure value of the mold cavity is further estimated.

According to the present invention, a curve of the process pressure and temperature change process of the process stage mold cavity is provided to achieve the goals of determining the quality of the finished product and verifying the functioning of the equipment. In order for the quality control system to be able to measure the parameters of the injection molding process, determining the quality of the injection molded product contributes significantly.
Due to the limited design of the detection structure, many different detectors must be used at different positions to monitor the mold condition, which complicates the installation and placement of the system and makes it impossible to detect from the same position. Although it could not be done, if the detector constructed by the present invention is used, it becomes possible to immediately measure changes in the temperature and pressure of the mold.
The pressure and temperature in the mold are measured using the detector according to the present invention, and the function calibration and the quality determination of the finished product on the line are performed by integrating with the conventional injection molding equipment. Since the pressure and temperature detecting device in the mold according to the present invention can immediately measure the pressure and temperature of the mold, the system of the conventional mold sensing technology is complicated and the integration of the mold is low. To solve.

In a conventional mold injection process, it is a graph simulating the change of pressure inside the mold and the actual pressure inside the mold. 1 is a schematic view of a cross section of an embodiment of a pressure and temperature detecting device in a mold according to the present invention applied to the mold. It is a front exploded view showing an embodiment of a pressure and temperature detecting device in a mold of the present invention. It is an inclination view showing a strained structure of an embodiment of a pressure and temperature detecting device in a mold of the present invention. FIG. 4 is a schematic view of an inclination in which the strained structure shown in FIG. 3 is deformed by receiving pressure. 1 is a front view of an embodiment of a pressure and temperature detecting device in a mold of the present invention, and a schematic view showing a state of the detecting device when a casting material is not injected into a mold cavity. FIG. 3 is a schematic view showing the operation of the pressure and temperature detecting device in the mold of the present invention when the casting material is injected into the mold cavity.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Needless to say, the present invention is not limited to the following examples and can be arbitrarily changed without departing from the gist of the present invention.

Hereinafter, the present invention will be described in more detail with reference to FIGS. The pressure and temperature detection device 1 of the present embodiment is applied to a mold A, and the pressure and temperature detection device 1 includes a frame body 11, a pedestal 12, a pressing lever 13, a strain structure 14, and a strain gauge 15. , And a temperature detection element 16.
The frame 11 is provided inside the mold A and is exposed in the space of the mold cavity B of the mold A on the ceiling surface 111 of the frame 11. The frame 11 has a passage 112 recessed in the ceiling surface 111 and an accommodation space 113 that is similarly installed in the frame 11 and communicates with the passage 112. The bottom surface 114 of the frame 11 has the accommodation space described above. It includes an open end 1141 communicating with 113.
The pedestal 12 is installed at the open end 1141 of the bottom surface 114 of the frame body 11. Specifically, as in the embodiment shown in FIGS. 3, 6, and 7, a male screw 123 is provided on the outer peripheral wall surface of the pedestal 12. The female screw 1142 is installed so as to correspond to the inner wall of the opening end 1141 of the frame 11 and these are screwed to each other, and the pedestal 12 is separably installed on the bottom surface 114 of the frame 11 ( Of course, when the pedestal 12 does not need to be removed, a method such as welding or adhesion may be adopted, and the pedestal 12 may be coupled to the open end 1141 of the bottom surface 114 of the frame body 11) and the accommodation space 113 To be blocked. A flat surface 121 is provided on the upper portion of the pedestal 12, and a through hole 122 that penetrates the central axis of the pedestal 12 is provided at the center of the pedestal 12.
The pressing lever 13 is installed in the accommodation space 113, and the front end 131 of the pressing lever 13 extends into the passage 112 and is exposed in the space of the mold cavity B. As shown in FIG. 7, when the mold hole B generates a pressure F, the front end 131 of the pressing lever 13 transmits the pressure of the mold hole B, and the pressing lever 13 moves in the passage 112 toward the accommodation space 113. Axial displacement toward.
The strain structure 14 is installed between the flat surface 121 and the rear end 132 of the pressing lever 13, and is localized on the flat surface 121. The strain structure 14 transfers the pressure transmitted by the displacement of the pressing lever 13. It is converted into the deformation amount of.
The strain gauge 15 is installed in the strain structure 14 and converted into deformation information 151 based on the amount of deformation of the strain structure 14. As a matter of course, there are a plurality of deforming members of the strain structure 14 (see the support beams 143 in FIG. 6), and they are installed one by one on the deforming member or one is selected.
The temperature detecting element 16 (that is, the pressing lever temperature sensing element 16a) is installed in the pressing lever 13 (as shown in FIGS. 3 and 6, a blind hole is formed at the center of the end surface of the rear end 132 of the pressing lever 13. 1322 is provided as a recess) and is used for measuring the immediate temperature of the pressing lever 13 and converting it into the pressing lever temperature information 16a1 (since the front end 131 of the pressing lever 13 is exposed from the mold cavity B, the pressing lever temperature The information 16a1 can acquire an accurate actual temperature value of the mold cavity B).
The processing unit 17 is electrically connected to the strain gauge 15 and the temperature detection element 16, respectively, and acquires the deformation information 151 and the pressure lever temperature information 16a1 and uses this as the basis for converting the deformation information into pressure information.

In one embodiment, the ceiling surface 111 of the frame body 11 is substantially horizontal to the mold hole surface B1, and in the initially installed state, when the pressure lever 13 does not receive the pressure F of the mold hole, the front end of the pressure lever 13 is The end surface of 131 and the ceiling surface 111 maintain flatness (see FIG. 6 ).
When the injection molding process is performed, the rise of the pressure generated by the injection of the casting material C in the mold hole B changes, and the pressure F of the mold hole B pushes the pressing lever 13 to press the pressing lever 13. 13 is pushed toward the upper portion of the strain structure 14 (see the pushing plate portion 141).
Since the strain structure 14 is localized on the flat surface 121 of the pedestal 12 to which the bottom portion (see the bottom plate portion 142) is fixed, the seat plate portion 142 of the strain structure 14 is fixed so as not to move, and the push plate portion 141 is transmitted. The supporting beam 143 is deformed by the applied pressure, and the deformation value is measured by the strain gauge 15 installed on the supporting beam 143 (see FIG. 7).

3, the pressing lever 13 may further include a lever body 133 connected to the front end 131, and a rear end flat surface 1321 connected to the lever body 133 and located at the rear end 132. The rear end flat surface 1321 is located in the accommodation space 113 and abuts on the strain structure 14. The diameter of the rear end flat surface 1321 is larger than the diameter of the passage 112, and the lever body 133 is covered with the elastic member 18 (for example, a compression spring or a conical washer). The movement limit is limited by the ceiling surface of 1321" and the "end surface of the accommodation space 113 connected to the passage 112".
After the pressing lever 13 releases the external force (pressure of the mold cavity), the elastic member 18 recovers the original state of the strain structure 14 and the pressing lever 13 is returned to the pressing plate portion 141 of the strain structure 14. Is used to contact the rear end 132 of the pressing lever 13 (that is, the bottom surface of the rear end flat surface 1321).

In one embodiment, the temperature sensing element 16 is a pressure lever temperature sensing element 16a and a strain structure temperature sensing element 16b, the pressure lever temperature sensing element 16a is installed on the pressure lever 13, and the strain structure temperature sensing element 16b is a strain structure 14. The pressure lever temperature information 16a1 and the strain structure temperature information 16b1 of the strain structure 14 are respectively measured and fed back to the processing unit 17.

In one embodiment, as shown in FIGS. 6 and 7, the strain structure 14 has a push plate portion 141, a seat plate portion 142, and both ends having elasticity to be connected to the push plate portion and the seat plate portion, respectively. And a pair of support beams 143. The seat plate portion 142 is positioned on the flat surface 121 (specifically, the positioning method forms a positioning slot 1421 recessed in the center position of the seat plate portion 142, and the corresponding flat surface 121 is fitted with the positioning slot 1421. The pressing plate portion 141 is adjacent to the rear end 132 of the pressing lever 13, and the two support beams 143 are installed so as to be parallel to the axial movement direction of the pressing lever 13 (the convex portion 1211 to be fitted is provided). (See FIG. 3).
The beam body 1431 of the pair of support beams 143 receives the pressure F applied by the push plate portion 141 and is then curved and deformed in the direction opposite to or opposite to the other support beams 143 (that is, the strained structure). 14 is curved toward the outside or inside, and the pair of support beams 143 is curved toward the outside of the strain structure 14 as shown in FIGS. 4 and 5.
The strain gauge 15 is installed on the beam body 1431 of one or two support beams 1431 of the support beams 143. The two support beams 143 may or may not have the same thickness, and the two support beams 143 are installed so as to have the same diameter or unequal diameter with respect to the central axis X of the strain structure 14. This is determined by the position and quantity at which the strain gauge 15 is installed on one or both of the two support beams 143 (see FIG. 3).

Of course, the support beams 143 described above are preferably made of a metal material, but the present invention is not limited to this, and may be made of a material such as ceramic, or even a plastic material at low temperatures. Alternatively, any material may be used as long as the support beams 143 receive the temperature of the mold process in the accommodation space 113 and the amount of deformation does not cause permanent deformation.

By the way, the through hole 1411 provided in the central portion of the push plate portion 141 of the strain structure 14, the through hole 1422 provided in the central portion of the seat plate portion 142, and the through hole 122 provided in the central portion of the pedestal 142 have these holes. The strain gauge 15 and the power and signal transmission lines (L1, L2) of the temperature detecting element 16 are penetrated to the outside of the frame 11 and the pedestal 12 (see FIGS. 6 and 7). As a matter of course, after the transmission lines (L1, L2) are drawn out from the through hole 122, they are hermetically sealed according to demand.

Further, the processing unit 17 respectively obtains the deformation information 151 of the strain structure 14 from the strain gauge 15 and the pressing lever temperature information 16a1 from the pressing lever temperature sensing element 16a, and the temperature corresponds to the amount of deformation generated by the material of the strain structure 14. After evaluating the influence of the pressure lever temperature information 16a1 (change in deformation amount at the same material but at different temperatures), the actual pressure value of the mold cavity is further estimated.
Further, when the pressing lever temperature sensing element 16a is installed on the pressing lever 13 and the strained structure temperature sensing element 16b is installed on the strained structure 14, the processing unit 17 causes the deformation information 151 of the strained structure 14 at the same time. , The strain structure temperature information 16b1 of the immediate temperature of the strain structure 14 and the pressing lever temperature information 16a1 are respectively acquired, and after converting the influence of the strain structure 14 on the deformation amount of the actual temperature, the actual pressure value of the mold cavity is calculated. Further estimate.
In this embodiment, the immediate temperature of the strained structure 14 is directly obtained, a more accurate effect of the amount of deformation is obtained, the pressure value of the actual mold cavity can be evaluated more accurately, and the process of the mold cavity can be evaluated in the process stage. It provides curves of pressure and mold temperature changes, and achieves the goals of determining the quality of finished products and verifying equipment functions.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and includes design changes and the like without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Pressure and temperature detection device 11 Frame body 111 Ceiling surface 112 Passage 113 Storage space 114 Bottom surface 1141 Opening end 1142 Female screw 12 Pedestal 121 Flat surface 1211 Convex part 122 Through hole 123 Male screw 13 Press lever 131 Front end 132 Rear end 1321 Rear end flat surface 1322 Blind hole 133 Lever body 14 Strain structure 141 Push plate part 1411 Through hole 142 Seat plate part 1421 Positioning slot 1422 Through hole 143 Support beam 1431 Beam body 15 Strain gauge 151 Deformation information 16 Temperature detection element 16a Push lever Temperature sensing element 16a1 Push Lever temperature information 16b Strain structure temperature sensing element 16b1 Strain structure temperature information 17 Processing unit 18 Elastic member A Mold B Mold hole B1 Mold hole surface C Casting material L1 Transmission line L2 Transmission line F Pressure X Central axis

Claims (10)

Structure
A frame body which is internally provided in a mold and whose ceiling surface is exposed from a mold hole of the mold, wherein a passage is recessed in the ceiling surface and communicates with a housing space in the frame body, A frame body having an open end communicating with the accommodation space on the bottom surface of the frame body;
A pedestal that is installed on the bottom surface of the frame body, seals the accommodation space, has a flat surface in the upper portion, and has a through hole in the central portion,
A pressing lever installed in the accommodation space and having a front end extending into the passage and exposed in the mold cavity, and after the pressure of the mold cavity is transmitted from the front end, the pressing lever is displaced in the axial direction in the passage. ,
A strain structure installed between the flat surface and the pressing lever, the strain structure for converting the pressure transmitted by the displacement of the pressing lever to the deformation amount of the strain structure,
At least one strain gauge installed in the strain structure, for measuring the amount of deformation of the strain structure and converting it into deformation information;
At least one temperature detection element installed on the pressing lever, for measuring the immediate temperature of the pressing lever and converting it into pressing lever temperature information;
A processing unit that is electrically connected to the strain gauge and the temperature detection element, respectively, and that acquires the deformation information and the pressing lever temperature information.
Pressure and temperature detection device in the mold. The ceiling surface of the frame body is substantially horizontal to the mold cavity surface, and at the time of initial installation, if the pressure lever is not receiving pressure, the front end surface of the pressure lever and the ceiling surface have flatness. The pressure and temperature detecting device in the mold according to claim 1, which is held. The pressing lever further includes a lever main body connected to the front end and a rear end flat surface connected to the lever main body and facing the front end, the rear end flat surface being located in the accommodation space. The rear end flat surface is in contact with a strained structure, the diameter of the rear end flat surface is larger than the diameter of the passage, the lever body is covered with elastic members, and both ends of the elastic member are separated from the rear end flat surface and the accommodation space. 3. The pressure and temperature detecting device in a mold according to claim 2, wherein the pressure detecting unit and the temperature detecting unit are respectively connected to end faces of the passages to limit movement limits of the elastic members. These temperature detecting elements are installed on the pressure lever and the strain structure, and are used to measure the pressure lever temperature information and the strain structure temperature information of the strain structure, respectively, and to feed them back to the processing unit. The pressure and temperature detecting device in the mold according to claim 1. The strained structure includes a push plate portion, a seat plate portion, and a pair of elastic support beams, both ends of which are connected to the push plate portion and the seat plate portion, respectively. The pressing plate portion is located on a flat surface, the pressing plate portion is adjacent to the rear end of the pressing lever, the pair of supporting beams are installed so as to be parallel to the moving direction of the pressing lever, and After the beam body is subjected to the pressure applied by the push plate portion, the beam body is respectively curved and deformed in a direction opposite to or opposite to the other support beams, and at least one strain gauge is provided in one of the pair of support beams. The pressure and temperature detecting device in a mold according to any one of claims 1 to 4, which is installed on a beam. The support beams are made of metal, ceramic, or plastic material, and the support beams are subjected to the temperature of the mold process in the accommodation space, and the amount of deformation is such that permanent deformation is not caused. The in-mold pressure and temperature detection device of claim 5. The seat plate portion is located in a positioning slot formed by recessing the flat surface at the center position of the seat plate portion, and the corresponding flat surface is provided with a convex portion to be fitted with the positioning slot. The in-mold pressure and temperature detection device of claim 5. The strain gauge and the center of the push plate portion of the strain structure, the center of the seat plate portion, so that the power and signal transmission lines of the temperature detection element penetrate to the outside of the frame and the pedestal. The pressure and temperature detecting device in the mold according to claim 4, wherein a through hole is provided in the central part of the base and the pedestal. The processing unit obtains the deformation information and the pressing lever temperature information respectively, and after evaluating the influence of the pressing lever temperature information on the amount of deformation generated by the material of the strained structure, the actual pressure value of the mold cavity is further calculated. The pressure and temperature detecting device in the mold according to claim 1, wherein the pressure and temperature are estimated. The processing unit deformation information of the strained structure at the same time, the immediate temperature of the strained structure, the temperature of the strained structure and the immediate temperature of the strained structure for the amount of deformation generated by the material of the strained structure, respectively. The pressure and temperature detecting device in the mold according to claim 4, wherein after the influence is converted, the actual pressure value of the mold cavity is further estimated.

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