Measuring jig for measuring thermal shrinkage rate of diaphragm
By using a heating stage and a non-contact measuring device on the diaphragm, the thermal shrinkage rate of the diaphragm can be monitored in real time, which solves the problem that the thermal shrinkage rate of the diaphragm cannot be measured quickly in the existing technology, improves the measurement accuracy and device life, and provides a basis for process optimization.
Patent Information
- Application Number
- CN202423098747.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-16
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2034-12-16
AI Technical Summary
Existing technologies cannot measure the change in thermal shrinkage rate of the film under high temperature conditions in real time and quickly, which makes it impossible to determine whether the expansion and contraction of the film exceeds the specifications when the backlight module is lit for a long time, thus affecting product quality.
A heating stage is used to simulate the heat source of the backlight module. Combined with a non-contact measuring device with a scale grating and a grating reading head, the changes in the edge of the diaphragm are monitored in real time by a height and low position distance sensor, which reduces heat interference and improves measurement accuracy and lifespan.
It enables real-time and rapid measurement of the film's heat shrinkage rate, improving measurement accuracy and device lifespan. It can also plot curves of heat shrinkage rate versus time and temperature, guiding process optimization and production.
Smart Images
Figure CN223611437U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to display industry measurement field more specifically, it relates to a kind of for determining the measuring fixture of diaphragm thermal shrinkage. BACKGROUND
[0002] There are several layers of diaphragm in display, and the backlight module at the back of the display emits light, which is modulated by the diaphragm to produce the required light.
[0003] The backlight module generates a large amount of heat during the light-emitting process, which is conducted to the diaphragm and causes the temperature rise of the diaphragm. The diaphragm will shrink after being heated.
[0004] Thermal shrinkage refers to the percentage change in size of a material after heating and cooling to the original temperature. In the display industry, there are strict requirements for the thermal shrinkage of diaphragm according to the characteristics of the module architecture. The current common test method for diaphragm thermal shrinkage is based on ASTM D1204 or GB / T 27584 test method. The sample is stored in an oven, the temperature and time are determined according to the tested material, and after the storage time is up, the sample is placed in room temperature for a period of time. The distance between the reference marks on the sample is measured using a 2.5-dimensional image instrument, and the thermal shrinkage of the diaphragm is calculated according to the linear size change formula: ΔD = [(Df-Do) / Do]*100.
[0005] According to this method, the thermal shrinkage of the diaphragm can be measured, but the required time is long, and it cannot be determined whether the expansion and contraction of the diaphragm under the condition of long-time lighting of the backlight module exceeds the specification, causing other effects (such as diaphragm adsorption). In order to prevent this phenomenon, a measuring fixture is needed to measure the shrinkage of the diaphragm under high temperature in real time and quickly. SUMMARY
[0006] The utility model overcomes the deficiency that the existing diaphragm measurement method cannot obtain real-time diaphragm shrinkage, and provides a measuring fixture for measuring diaphragm thermal shrinkage, which can obtain the shrinkage of the diaphragm in real time, thereby better simulating the expansion and contraction of the diaphragm under the condition of long-time lighting of the backlight module, providing reference for process optimization, and ultimately improving product quality.
[0007] To solve the above technical problems, the utility model adopts the following technical solutions:
[0008] The utility model provides a measuring jig for determining the heat shrinkage of a diaphragm, which is attached to the heating surface of a heating table, comprising a measuring frame, a positioning device and a shrinkage measuring device, the measuring frame comprises a measuring rod, which is arranged horizontally above the table top of the heating table, two sliders are adjustably connected to the measuring rod, the positioning device is arranged on the sliders to determine the edges of the diaphragm, and the shrinkage measuring device comprises a scale grating and a grating reading head, the scale grating is arranged horizontally on the measuring rod, and the grating reading head is fixedly connected to the sliders.
[0009] The diaphragm is attached to the heating table, which provides heat for the diaphragm, causing the temperature of the surface of the diaphragm to rise. The two sliders on the measuring rod are used to track the two edges of the diaphragm in the direction of the measuring rod, and the positioning device and the shrinkage measuring device can non-contact determine the edges of the diaphragm and record the distance of the movement of the sliders in the process, thereby obtaining the necessary dimensional change for measuring the heat shrinkage.
[0010] Specifically, the shrinkage measuring device comprises a scale grating and a grating reading head, which is also called a grating ruler, and is a measuring feedback device that works by using the optical principle of a grating. The grating ruler is often used in the closed-loop servo system of a numerical control machine tool and can be used for detecting linear displacement or angular displacement. The signal output by the grating ruler is a digital pulse, which has the characteristics of large detection range, high detection precision and fast response speed.
[0011] The precise measuring device can be disturbed by heat, and the positioning device and the shrinkage measuring device in the utility model are arranged on the measuring frame and use a non-contact measuring method, which can reduce the disturbance of the heating table on the positioning device and the shrinkage measuring device, thereby prolonging the service life of the positioning device and the shrinkage measuring device and improving the precision of the positioning device and the shrinkage measuring device.
[0012] As a preferred embodiment, the positioning device is a height position distance sensor, which is communicatively connected to a controller, and the height position distance sensor determines the edges of the diaphragm by comparing the height difference between the diaphragm and the heating surface of the heating table. The height position distance sensor can measure the distance between the sensor and the measurement object. During the movement of the sliders, the height position distance sensor passes from above the diaphragm to above the heating table, and due to the thickness of the diaphragm, the distance information obtained by the height position distance sensor at this time has a significant jump, so the edges of the diaphragm can be accurately positioned according to this feature. In some embodiments, the height position distance sensor is a laser distance sensor, which reflects the laser generated by the light source after reaching the object. Since the heating table is a smooth plane, the sensor has low interference and error. According to the selection of the light source of the laser distance sensor, the light emitted by the laser distance sensor is reflected when it reaches the diaphragm.
[0013] As preferred, a scale rod is fixedly connected to the measuring frame, the scale rod and the measuring rod are arranged in parallel, and the scale grating is attached to the scale rod along the length direction.
[0014] As preferred, the length of the measuring rod is greater than the maximum diagonal line of the heating table. This structure makes the placement angle of the measuring rod not be restricted by the size of the measuring rod and the heating table.
[0015] As preferred, the measuring frame further comprises a supporting rod, and the supporting rod is fixedly connected to the end of the measuring rod. The supporting rod supports the measuring rod to keep the measuring rod suspended.
[0016] As preferred, the length of the supporting rod is adjustable to adjust the height of the measuring rod. Through this feature, the measuring rods arranged in different directions and staggered can be avoided at different heights.
[0017] As preferred, the sliding block is sleeved on the measuring rod and is in sliding connection with the measuring rod.
[0018] Compared with the prior art, the beneficial effects of the utility model are:
[0019] (1) The heating table is used to replace the oven to heat, so that the heat transfer mode of the backlight module to the diaphragm can be better simulated, and the obtained thermal shrinkage rate change is closer to the real situation;
[0020] (2) The positioning device and the shrinkage measuring device are suspended, this feature reduces the influence of temperature on the positioning device and the shrinkage measuring device, and improves the measurement accuracy and the service life of the measuring jig;
[0021] (3) The jig is arranged in an open environment, can be measured multiple times, so that the thermal shrinkage rate-time-temperature curve is obtained, and the design and production are better guided. BRIEF DESCRIPTION OF DRAWINGS
[0022] Figure 1 is the isometric view of the utility model;
[0023] Figure 2 is the top view of the utility model;
[0024] Figure 3 is the schematic view of the measuring frame of the utility model;
[0025] Figure 4 is Figure 3 is the enlarged view of A in figure.
[0026] In the figure:
[0027] The heating table 1, the diaphragm 2, the measuring frame 3, the measuring rod 4, the supporting rod 5, the sliding block 6, the positioning device 7, the scale grating 8, the grating reading head 9, and the scale rod 10. DETAILED DESCRIPTION
[0028] The present disclosure will be further described below in conjunction with the accompanying drawings and embodiments.
[0029] It should be noted that the following detailed description is illustrative only, and is intended to provide further description in order to provide a thorough understanding of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
[0030] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.
[0031] In the present disclosure, the terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only a relationship word determined for the convenience of describing the structural relationship of the components or elements of the present disclosure, and cannot be understood as a limitation of the present disclosure.
[0032] In the present disclosure, the terms such as "fixedly connected", "connected", "connected" should be understood broadly, which means that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. For relevant researchers or technicians in the art, the specific meaning of the above terms in the present disclosure can be determined according to the specific circumstances, and cannot be understood as a limitation of the present disclosure.
[0033] Embodiment:
[0034] The detection process of thermal shrinkage rate is: measuring the size of the film 2, measuring again after heating the film 2, and obtaining the thermal shrinkage rate of the film 2 according to the formula mentioned in the background art according to the size obtained before and after.
[0035] In order to better simulate the heat transfer mode of the backlight module to the film 2, a heating table 1 is used as a heat source to heat the film 2.
[0036] Referring to Figure 1 , Figure 2 As shown in the figure, on this basis, a measuring jig for measuring the thermal shrinkage rate of the film 2 is set: the measuring jig includes a measuring frame 3, a positioning device 7 and a shrinkage measuring device. Referring to Figure 3 As shown in the figure, the measuring frame 3 includes a measuring rod 4, and two sliding blocks 6 are adjustably connected on the measuring rod 4. The positioning device 7 is arranged on the sliding block 6 to determine the edge of the film 2. Referring toFigure 4 As shown, the shrinkage measuring device comprises a scale grating 8 and a grating reading head 9, the scale grating 8 is arranged horizontally with the measuring rod 4, and the grating reading head 9 is fixedly connected to the sliding block 6. The positioning device 7 is used to determine the edge of the film 2.
[0037] The two sliding blocks 6 on the measuring rod 4 are respectively used to track the two edges of the film 2 in the direction of the measuring rod 4, and the positioning device 7 and the shrinkage measuring device can non-contactly position the edges of the film 2 and record the distance of the movement of the sliding block 6 in the process, so as to obtain the necessary size change for measuring the thermal shrinkage rate.
[0038] The positioning device 7 is a height position distance sensor, and the sensor is communicatively connected with a controller. The grating reading head 9 is also communicatively connected with the controller. The height position distance sensor determines the edge of the film 2 by comparing the height difference between the film 2 and the heating surface of the heating table 1. The height position distance sensor can measure the distance between the sensor and the measurement object. In the process of moving with the sliding block 6, the height position distance sensor passes from above the film 2 to above the heating table 1. Due to the existence of the thickness of the film 2, there is a significant jump in the distance information obtained by the height position distance sensor at this time, and according to this feature, the edge of the film 2 can be accurately positioned. The height position distance sensor adopts a laser distance sensor in some embodiments, and the sensor reflects the laser generated by the light source to the object. Since the heating table 1 is a smooth plane, the interference and error of the sensor are low. According to the selection of the light source of the laser distance sensor by the film 2, the light emitted by the laser distance sensor is reflected when reaching the film 2.
[0039] Referring to Figure 3 As shown, the measuring frame 3 is fixedly connected with a scale rod 10, the scale rod 10 is arranged in parallel with the measuring rod 4, and the scale grating 8 is attached to the scale rod 10 along the length direction. The scale rod 10 can be arranged on the side or above the measuring rod 4. The present embodiment and the corresponding drawings take the side as an example.
[0040] The precise measuring device will be disturbed by heat. The positioning device 7 and the shrinkage measuring device in the present application are arranged on the measuring frame 3, and adopt a non-contact measuring mode, which can reduce the interference of the heating table 1 on the positioning device 7 and the shrinkage measuring device, thereby prolonging the service life of the positioning device 7 and the shrinkage measuring device, and improving the accuracy of the positioning device 7 and the shrinkage measuring device.
[0041] Referring to Figure 3As shown, the measuring frame 3 comprises a supporting rod 5 in addition to the measuring rod 4, the supporting rod is fixedly connected to the end of the measuring rod 4. The supporting rod supports the measuring rod 4 to keep the measuring rod 4 suspended. The length of the supporting rod 5 is adjustable to adjust the height of the measuring rod 4. Through this feature, the measuring rods 4 arranged in different directions and staggered can be avoided at different heights. The adjustable way of the supporting rod 5 includes replacing the supporting rod of different lengths connected to the measuring rod 4 and the telescopic structure of the supporting rod 5 with adjustable length. The length of the measuring rod 4 is greater than the maximum diagonal line of the heating table 1. This structure makes the placement angle of the measuring rod 4 not be restricted by the size of the measuring rod 4 and the heating table 1.
[0042] The adjustable connection of the aforementioned slide block 6 and the measuring rod 4 includes that the slide block 6 is sleeved on the measuring rod 4 and is in sliding connection with the measuring rod 4. In some other embodiments, the connection can also be made through a screw rod slide block 6 pair. This connection mode cooperates with the motor rotating the driving screw rod in communication connection with the controller to also realize the automatic adjustment of the movement of the slide block 6.
[0043] The general use of the device is as follows:
[0044] Cut the film sheet 2 to a standard size (for example, 100mmX100mm) and place the film sheet 2 on the heating table 1, at this time, the heating table 1 is in a non-heating state;
[0045] Place the first measuring frame 3 so that the first measuring rod 4 is across above the film sheet 2 and in some preferred schemes is parallel to one side of the film sheet 2;
[0046] Place the second measuring frame 3 so that the second measuring rod 4 is across above the film sheet 2 and the first measuring frame 3, so that the second measuring rod 4 is parallel to the other side of the film sheet 2, and the first measuring frame 3 and the second measuring frame 3 are substantially perpendicular;
[0047] Adjust the total of four slide blocks 6 on the two measuring frames 3, move the slide blocks 6 to align the edges of the film sheet 2 through the positioning device 7;
[0048] Record the accurate length of the film sheet 2 in this direction obtained by the shrinkage measuring device through the controller;
[0049] Start the heating table 1 to heat the film sheet 2;
[0050] Adjust the four slide blocks 6 every interval of time, move the slide blocks 6 to align the edges of the film sheet 2 through the positioning device 7, and record the signal representing the distance output by the shrinkage measuring device through the controller;
[0051] End the heating of the heating table 1 after reaching the preset time, and draw the thermal shrinkage rate curve of the film sheet 2 of this model according to the aforementioned data.
[0052] The above-mentioned embodiments are only preferred solutions of the present application, and do not limit the present application in any form, and other variants and modifications are possible without departing from the technical solutions recited in the claims.
Claims
1. A measuring fixture for determining the thermal shrinkage rate of a diaphragm, characterized in that, The diaphragm is attached to the heating surface of the heating table, including a measuring frame, a positioning device and a shrinkage measuring device, the measuring frame includes a measuring rod, the measuring rod is horizontally arranged above the table top of the heating table, two sliders are adjustably connected to the measuring rod, the positioning device is arranged on the sliders to determine the edge of the diaphragm, the shrinkage measuring device includes a scale grating and a grating reading head, the scale grating is horizontally arranged with the measuring rod, and the grating reading head is fixedly connected to the sliders.
2. The measuring jig for measuring the heat shrinkage of a diaphragm according to claim 1, wherein The positioning device is a height position distance sensor, the sensor is communicatively connected with a controller, and the height position distance sensor determines the edge of the diaphragm by comparing the height difference between the diaphragm and the heating surface of the heating table.
3. The measuring jig for measuring the heat shrinkage of a diaphragm according to claim 1, wherein A scale rod is fixedly connected to the measuring frame, the scale rod and the measuring rod are arranged in parallel, and the scale grating is attached to the scale rod along the length direction.
4. The measuring jig for measuring the heat shrinkage of a diaphragm according to claim 1, wherein The length of the measuring rod is greater than the maximum diagonal line of the heating table.
5. The measuring jig for measuring the heat shrinkage of a diaphragm according to claim 1, wherein The measuring frame further includes a supporting rod, and the supporting rod is fixedly connected to the end of the measuring rod.
6. The measuring jig for measuring the heat shrinkage of a diaphragm according to claim 5, wherein The length of the supporting rod is adjustable to adjust the height of the measuring rod.
7. The measuring jig for measuring the heat shrinkage of a diaphragm according to any one of claims 1 to 6, characterized in that, The sliders are sleeved on the measuring rod and are in sliding connection with the measuring rod.