A gypsum board moisture deflection tester

Abstract

The present application relates to the technical fields of gypsum board moisture deflection measurement, and specifically relates to a gypsum board moisture deflection tester, which comprises a constant temperature and humidity chamber, a plurality of moisture inlet pipes are distributed on both sides of the constant temperature and humidity chamber, a temperature and humidity sensor is installed on the inner top surface, and a moving assembly is installed on the top of the inner cavity. A mounting bracket is installed on the top of the moving assembly, and a range finder is detachably installed at the bottom end of the mounting bracket. A plurality of sliding assemblies are arranged on the inner walls of both sides of the constant temperature and humidity chamber along the vertical direction at equal intervals, a placing frame is connected between two sliding assemblies at the same height, a placing table is arranged in the placing frame, a placing groove is arranged on the top of the placing table, a mass sensor is installed on the inner bottom surface of the placing frame and connected with the bottom end of the placing table. The application further comprises an external temperature and humidity control device connected with the moisture inlet pipes through a gas pipe. The present application realizes in-situ non-contact deflection measurement and synchronous monitoring of mass change of the gypsum board under the moisture state, has high testing precision, can realize multi-layer synchronous testing, and effectively improves the detection efficiency and data accuracy.

Description

Technical Field

[0001] This invention relates to the technical field of measuring the deflection of gypsum board under moisture, specifically a gypsum board deflection measuring instrument. Background Technology

[0002] As a widely used decorative and partition material in modern architecture, gypsum board's resistance to bending deformation after being exposed to moisture (i.e., moisture deflection) is a key indicator for measuring product quality and safety. According to relevant national standards and industry specifications, after gypsum board has been placed in a specific temperature and humidity environment for a period of time, the vertical displacement changes at its center and edges must be measured.

[0003] Current equipment and methods for measuring the deflection of gypsum board under moisture conditions have the following technical shortcomings:

[0004] Insufficient measurement accuracy and ease of operation: Traditional measurement methods often involve manually removing the gypsum board from the constant temperature and humidity chamber and then using a dial indicator or micrometer for contact measurement. This operation is not only cumbersome, but also exposes the gypsum board to an uncontrolled external environment during removal and transfer, which can easily lead to surface moisture loss or temperature changes, affecting the accuracy and real-time nature of the deflection data. In addition, the contact measurement probe itself carries the risk of applying additional stress to the sample surface and interfering with natural deformation.

[0005] Simultaneous testing of multiple samples is inefficient: Existing equipment has limited internal space utilization, making it difficult to simultaneously perform independent layered monitoring of multiple gypsum boards of different specifications or batches while ensuring uniform airflow distribution. This often necessitates batch testing, resulting in long testing cycles, and the differences in temperature and humidity microenvironments between different batches affect the comparability of results.

[0006] Lack of in-situ real-time quality monitoring: The mass of gypsum board changes during moisture absorption, and this parameter is strongly correlated with changes in deflection. Existing technologies typically perform mass weighing and deflection measurement separately, making it impossible to simultaneously obtain mass gain and deformation data of the same sample while maintaining an uninterrupted moisture state. This is not conducive to a comprehensive analysis of the moisture-induced deformation mechanism of the material.

[0007] Internal airflow disturbance interference: When moisture is introduced into a traditional constant temperature and humidity chamber, the airflow directly impacts the inside of the chamber, which can easily cause excessively high local wind speeds or temperature fluctuations, resulting in uneven moisture distribution on the gypsum board surface, and thus interfering with the accurate results of deflection measurement.

[0008] Therefore, there is an urgent need to develop an integrated measuring instrument that can achieve in-situ, non-contact, and high-precision synchronous monitoring of the moisture content and deflection changes of multiple gypsum boards. Summary of the Invention

[0009] The purpose of this invention is to provide a gypsum board deflection tester to solve the problems mentioned in the background art.

[0010] To achieve the above objectives, the present invention provides the following technical solution:

[0011] A gypsum board deflection tester for moisture absorption includes a constant temperature and humidity chamber, a door installed at the front of the chamber, a control box installed on the outer wall of the chamber, several humidification inlet pipes evenly distributed on both sides of the chamber, a temperature and humidity sensor installed on the inner top surface of the chamber, a moving component installed on the top of the inner cavity of the chamber, a mounting frame installed on the top of the moving component, a downward-facing rangefinder detachably installed at the bottom of the mounting frame, the moving component being used to move the mounting frame horizontally, several sliding components evenly spaced along the vertical direction on both inner walls of the chamber, a placement frame connected between two sliding components of the same height, a placement platform inside the placement frame, a placement groove for placing sample gypsum board on the top of the placement platform, a mass sensor installed on the inner bottom surface of the placement frame, the top of the mass sensor connected to the bottom of the placement platform, and a temperature and humidity control device located outside the chamber, the temperature and humidity control device being connected to the humidification inlet pipes via an air supply pipe.

[0012] As a further embodiment of the present invention: the moving component includes two track frames respectively installed on the inner walls of the top two sides of the constant temperature and humidity chamber, and a movable frame horizontally disposed between the two track frames. A first threaded rod is rotatably connected to each of the two movable frames, and a track rod is fixedly connected to each of the two movable frames. One end of the movable frame is threadedly connected to the first threaded rod, and the other end of the movable frame is inserted into the track rod. A first drive motor is installed on the outer wall of one end of one of the track frames. The output end of the first drive motor is connected to one end of the first threaded rod. The top of the mounting frame is connected to the bottom of the movable frame. The track frame is used to drive the movable frame to move in the forward and backward direction, and the movable frame is used to drive the mounting frame to move in the left and right direction.

[0013] As a further embodiment of the present invention: a second threaded rod is rotatably connected inside the movable frame, a second drive motor is installed on the inner wall of one end of the movable frame, the output end of the second drive motor is connected to one end of the second threaded rod, a movable block is threadedly connected to the second threaded rod, the top end of the mounting bracket is connected to the bottom end of the movable block, and a movable groove for the mounting bracket to move is opened at the bottom end of the movable frame.

[0014] As a further embodiment of the present invention: the sliding assembly includes two track plates that are symmetrically distributed and installed on the inner wall of the constant temperature and humidity chamber, and several crossbars that are evenly distributed and connected to the outer wall of the placement frame. One end of each crossbar extends between the two track plates and is connected to a pulley. The two track plates are provided with grooves along their length on the side that is close to each other. The top and bottom of the pulleys are respectively embedded in the two grooves.

[0015] As a further aspect of the present invention: a handle is installed at the front end of the placement frame, and both the placement frame and the placement platform are made of lightweight material.

[0016] As a further aspect of the present invention: a sealing and shock-absorbing sleeve is provided at the connection between the humidifier pipe and the side wall of the constant temperature and humidity chamber, and the sealing and shock-absorbing sleeve is wrapped around the middle periphery of the humidifier pipe.

[0017] As a further embodiment of the present invention: the bottom of the constant temperature and humidity chamber is equipped with casters, and a push rod is installed on one side of the outer wall of the constant temperature and humidity chamber.

[0018] The present invention has the following advantages:

[0019] 1. Achieve in-situ, non-contact, high-precision deflection measurement: Through a moving component and a rangefinder (such as a laser displacement sensor) installed inside the constant temperature and humidity chamber, horizontal scanning measurements of the gypsum board placed in the lower slot can be automatically performed without opening the chamber door or interrupting the moisture absorption process. This avoids microenvironmental disruption and human error caused by sample removal, significantly improving the authenticity and accuracy of deflection data. The rangefinder is detachably installed facing downwards for easy maintenance and calibration.

[0020] 2. Supports simultaneous independent testing of multiple samples in layers: Sliding components and placement frames are evenly spaced along the vertical direction on both sides of the inner wall of the chamber, enabling independent support for multiple layers of gypsum board. Combined with the horizontal movement and coverage capability of the moving components, one device can simultaneously perform automatic data acquisition on multiple samples at different heights and different moisture levels, significantly improving detection throughput and testing efficiency, while ensuring a high degree of consistency in the microenvironment of the same batch of tests.

[0021] 3. Integrated real-time monitoring of mass and deflection: A unique design incorporates a mass sensor mounted on the bottom surface of the placement frame, with the placement platform connected to its top. This structure allows the instrument to simultaneously monitor changes in the center deflection of the gypsum board and collect real-time data on the mass increment caused by moisture absorption. This provides a completely synchronized, two-parameter coupled basis for studying the deformation patterns of gypsum boards under moisture, resulting in highly valuable data.

[0022] 4. Stable internal environment and uniform airflow: Warm and humid gas is introduced through evenly distributed humidification pipes on both sides, combined with closed-loop control by temperature and humidity sensors at the top, ensuring the uniformity and stability of the temperature and humidity field inside the chamber. The sealed shock-absorbing sleeve design effectively isolates vibrations from the gas pipeline and external air disturbances, preventing local airflow impacts from interfering with the free deformation of the gypsum board.

[0023] 5. The structure is rationally designed and easy to operate and maintain: The sliding assembly uses a pulley and track plate combination, allowing the placement frame to be smoothly pulled out like a drawer. Combined with the handle design, this greatly facilitates the loading and unloading of samples. The bottom of the entire device is equipped with casters and push rods, enhancing the instrument's mobility in different laboratory settings. Attached Figure Description

[0024] Figure 1 This is a front view of the overall external structure of an embodiment of the present invention.

[0025] Figure 2 This is a front view of the overall internal structure of an embodiment of the present invention.

[0026] Figure 3 This is a front view of the structure of the placement frame and sliding component in an embodiment of the present invention.

[0027] Figure 4 This is a front view of the internal structure of the moving component in an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of the external structure of the mobile component in an embodiment of the present invention.

[0029] In the diagram: 1. Constant temperature and humidity chamber; 2. Chamber door; 3. Control box; 4. Casters; 5. Push rod; 6. Humidity inlet pipe; 7. Control valve; 8. Temperature and humidity control device; 9. Gas supply pipe; 10. Sealing and shock-absorbing sleeve; 11. Temperature and humidity sensor; 12. Moving component; 13. Mounting frame; 14. Rangefinder; 15. Sliding component; 16. Placement frame; 17. Handle; 18. Placement platform; 19. Sample gypsum board; 20. Mass sensor; 21. Crossbar; 22. Pulley; 23. Track plate; 24. Slide groove; 25. Track frame; 26. Track rod; 27. First threaded rod; 28. First drive motor; 29. ​​Movable frame; 30. Second threaded rod; 31. Movable block; 32. Movable groove; 33. Second drive motor. Detailed Implementation

[0030] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0031] The technical solution of the present invention will be further described in detail below with reference to specific embodiments.

[0032] Example 1: Please refer to Figures 1 to 5 A gypsum board deflection tester for moisture absorption includes a constant temperature and humidity chamber 1. A door 2 is hinged to the front of the chamber 1, and a transparent observation window is embedded in the door 2 for real-time observation of the internal sample status. A control box 3 is installed on the outer wall of the chamber 1, and a programmable logic controller (PLC) is integrated within the control box 3 to control the movement trajectory and data acquisition of a moving component 12. Several moisture inlet pipes 6 are evenly distributed on both side walls of the chamber 1. A temperature and humidity sensor 11 is fixedly installed on the inner top surface of the chamber 1 with screws. The moving component 12 is installed on the top of the inner cavity of the chamber 1. A mounting bracket 13 is installed on the top of the movable part of the moving component 12. A downward-facing rangefinder 14 is detachably installed at the bottom of the mounting bracket 13 via a snap-fit ​​or threaded connection. The rangefinder 14 is preferably a high-precision laser displacement sensor. The moving component 12 is used to drive the mounting frame 13 and the rangefinder 14 to move in a two-dimensional plane in the horizontal direction. Several sets of sliding components 15 are equally spaced along the vertical direction on both inner walls of the constant temperature and humidity chamber 1. A placement frame 16 is horizontally connected between two sliding components 15 at the same height. A placement platform 18 is provided inside the placement frame 16. A placement groove for placing the sample gypsum board 19 is provided on the top of the placement platform 18. A mass sensor 20 is fixedly installed at the center of the inner bottom surface of the placement frame 16 by screws. The top of the mass sensor 20 is rigidly contacted and fixedly connected to the center of the bottom of the placement platform 18 to ensure the stability and accuracy of mass transfer. A temperature and humidity control device 8 is also included outside the constant temperature and humidity chamber 1. The temperature and humidity control device 8 is connected to the humidity inlet pipe 6 through an air supply pipe 9. Each humidity inlet pipe 6 is independently equipped with a control valve 7 to finely adjust the flow rate at each air inlet point.

[0033] The movable component 12 includes two parallel track frames 25, which are respectively fixed to the inner walls of the top two sides of the constant temperature and humidity chamber 1 by bolts, and a movable frame 29 horizontally arranged between the two track frames 25. A first threaded rod 27 is rotatably connected to each of the two track frames 25, and a smooth cylindrical track rod 26 is fixedly connected to each of them. One end of the movable frame 29 has a threaded sleeve embedded inside, which is threadedly connected to the first threaded rod 27. The other end of the movable frame 29 has a through hole, through which it is slidably fitted onto the track rod 26, forming a stable structure with one end driven and the other end guided. A first drive motor 28 is fixedly mounted on the outer wall of one end of one track frame 25 via a motor mount. The output end of the first drive motor 28 is connected to one end of the first threaded rod 27 via a coupling. The top of the mounting frame 13 is slidably connected to the bottom of the movable frame 29. The rotation of the first threaded rod 27 inside the track frame 25 drives the movable frame 29 to move forward and backward (Y-axis direction), and the movable frame 29 drives the mounting frame 13 to move left and right (X-axis direction).

[0034] A second threaded rod 30 is rotatably connected within the movable frame 29 along its length. A second drive motor 33 is fixedly mounted on the inner wall of one end of the movable frame 29 via a motor mount. The output end of the second drive motor 33 is connected to one end of the second threaded rod 30 via a coupling. A movable block 31 with a slider structure is threadedly connected to the second threaded rod 30. The outer wall of the movable block 31 slides against the inner wall of the movable frame 29 to restrict its rotation. The top end of the mounting bracket 13 is fixedly connected to the bottom end of the movable block 31 by bolts. The bottom end of the movable frame 29 has an elongated movable groove 32 along its length for the mounting bracket 13 to move freely along the X-axis.

[0035] The sliding assembly 15 includes two track plates 23 that are symmetrically distributed vertically and fixed to the inner wall of the constant temperature and humidity chamber 1 by bolts, and several horizontal bars 21 that are evenly distributed and horizontally welded or integrally formed and connected to the outer wall of the placement frame 16. One end of the horizontal bar 21 extends between the two track plates 23 and is rotatably connected to a pulley 22. The two track plates 23 have arc-shaped or rectangular grooves 24 along their length on the side that is close to each other. The top and bottom of the pulley 22 are respectively embedded in the two grooves 24 and roll with them, so that the placement frame 16 can be smoothly pulled and slid along the track plates 23.

[0036] The front end of the placement frame 16 is fixed with a recessed handle 17 by screws, so that the operator can pull it out without disturbing the internal airflow. Both the placement frame 16 and the placement platform 18 are made of lightweight materials such as aluminum alloy or carbon fiber to minimize the occupation of the range of the mass sensor 20 and improve the resolution of mass measurement.

[0037] Example 2: See Figure 1 , Figure 2 Based on Embodiment 1, a sealing and shock-absorbing sleeve 10 is provided at the connection between the humidification air inlet pipe 6 and the side wall of the constant temperature and humidity chamber 1. The sealing and shock-absorbing sleeve 10 is tightly wrapped around the middle periphery of the humidification air inlet pipe 6. The material of the sealing and shock-absorbing sleeve 10 is preferably silicone rubber or fluororubber, which can not only seal and insulate, but also absorb the mechanical vibration transmitted by the air supply pipe 9.

[0038] The bottom of the constant temperature and humidity chamber 1 is rotatably mounted with casters 4 via a support frame. The casters 4 have a self-locking brake function. A push rod 5 is welded or bolted to one side of the outer wall of the constant temperature and humidity chamber 1. The surface of the push rod 5 is covered with an anti-slip rubber sleeve.

[0039] The present invention provides a gypsum board deflection tester under moisture conditions, the specific working process and control principle of which are as follows:

[0040] Test preparation stage: The operator moves the instrument to the designated position using push rod 5 and locks the motion wheels 4. Open the chamber door 2, and using handle 17, pull the placement frame 16 out along the slide groove 24 of the track plate 23. Place the pre-treated and weighed sample gypsum board 19 smoothly into the placement slot at the top of the placement platform 18. Then push the placement frame 16 back into the chamber and close the chamber door 2. Set the target temperature and humidity, test duration, and data acquisition frequency using the control box 3.

[0041] Environment setup and humidity absorption stage: The temperature and humidity control device 8 is activated, generating air at a specific temperature and humidity, which is evenly introduced into the constant temperature and humidity chamber 1 through the air supply pipe 9, control valve 7, and humidity inlet pipe 6. The sealing and shock-absorbing sleeve 10 effectively isolates pipeline vibration. The temperature and humidity sensor 11 monitors the environment inside the chamber in real time and feeds back to the temperature and humidity control device 8 for closed-loop regulation to ensure constant environmental parameters. The sample gypsum board 19 begins to absorb moisture in the controlled environment.

[0042] Data Synchronization Acquisition Phase: During the experiment, the mass sensor 20 on the bottom surface of the placement frame 16 senses the total mass change of the placement platform 18 and the sample gypsum board 19 in real time, and transmits the mass increment data to the control box 3 in real time. Simultaneously, the moving component 12 operates automatically according to a preset program: the first drive motor 28 drives the first threaded rod 27 to rotate, causing the movable frame 29 and mounting bracket 13 to move along the Y-axis; the second drive motor 33 drives the second threaded rod 30 to rotate, causing the movable block 31 and mounting bracket 13 to move along the X-axis. The two work together, enabling the rangefinder 14 at the bottom of the mounting bracket 13 to perform grid-based scanning or fixed-point measurement of the upper surface of the stationary sample gypsum board 19 below.

[0043] Data Processing and Calculation: The rangefinder 14 accurately measures the distance between itself and preset points on the surface of the sample gypsum board 19 in a non-contact manner. By comparing the distance differences between the initial moment of the test and each moment during the test, and combining this with the position coordinates of the moving component 12, the system automatically calculates the maximum deflection and deformation profile of the sample gypsum board 19 under different moisture exposure times. Since the mass sensor 20 works synchronously with the rangefinder 14, the control box 3 ultimately outputs a mass-deflection coupling data curve containing timestamps, providing accurate and multi-dimensional scientific basis for evaluating the moisture resistance performance of the gypsum board.

[0044] All components of this invention are general standard parts or parts known to those skilled in the art. Their structure and principles are readily known to those skilled in the art through technical manuals or conventional experimental methods. It is obvious to those skilled in the art that this invention is not limited to the details of the above exemplary embodiments, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this invention is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0045] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A gypsum board deflection tester for moisture absorption, comprising a constant temperature and humidity chamber, wherein a door is installed at the front end of the constant temperature and humidity chamber, characterized in that, A control box is installed on the outer wall of the constant temperature and humidity chamber. Several humidity inlet pipes are evenly distributed on both sides of the chamber. A temperature and humidity sensor is installed on the inner top surface of the chamber. A moving component is installed on the top of the inner cavity of the chamber. A mounting frame is installed on the top of the moving component. A downward-facing rangefinder is detachably installed at the bottom of the mounting frame. The moving component is used to move the mounting frame horizontally. Several sliding components are evenly spaced along the vertical direction on both inner walls of the chamber. A placement frame is connected between two sliding components of the same height. A placement platform is set in the placement frame. A placement groove for placing gypsum board samples is set on the top of the placement platform. A mass sensor is installed on the inner bottom surface of the placement frame. The top of the mass sensor is connected to the bottom of the placement platform. The chamber also includes a temperature and humidity control device located outside the chamber. The temperature and humidity control device is connected to the humidity inlet pipes through a gas supply pipe.

2. The gypsum board deflection tester according to claim 1, characterized in that, The moving assembly includes two track frames respectively installed on the inner walls of the top two sides of the constant temperature and humidity chamber, and a movable frame horizontally arranged between the two track frames. A first threaded rod is rotatably connected to each of the two movable frames, and a track rod is fixedly connected to each of the two movable frames. One end of the movable frame is threadedly connected to the first threaded rod, and the other end of the movable frame is inserted into the track rod. A first drive motor is installed on the outer wall of one end of one of the track frames. The output end of the first drive motor is connected to one end of the first threaded rod. The top of the mounting frame is connected to the bottom of the movable frame. The track frames are used to drive the movable frame to move in the forward and backward direction, and the movable frame is used to drive the mounting frame to move in the left and right direction.

3. The gypsum board deflection tester according to claim 2, characterized in that, The movable frame is rotatably connected to a second threaded rod. A second drive motor is installed on the inner wall of one end of the movable frame. The output end of the second drive motor is connected to one end of the second threaded rod. A movable block is threadedly connected to the second threaded rod. The top end of the mounting frame is connected to the bottom end of the movable block. The bottom end of the movable frame is provided with a movable groove for the mounting frame to move.

4. The gypsum board deflection tester according to claim 1, characterized in that, The sliding assembly includes two track plates that are symmetrically distributed and installed on the inner wall of the constant temperature and humidity chamber, and several crossbars that are evenly distributed and connected to the outer wall of the placement frame. One end of each crossbar extends between the two track plates and is connected to a pulley. The two track plates have grooves along their length on the side that is close to each other. The top and bottom of the pulleys are respectively embedded in the two grooves.

5. A gypsum board deflection tester based on claim 4, characterized in that, The front end of the placement frame is equipped with a handle, and both the placement frame and the placement platform are made of lightweight materials.

6. The gypsum board deflection tester according to claim 1, characterized in that, A sealing and shock-absorbing sleeve is provided at the connection between the humidifier inlet pipe and the side wall of the constant temperature and humidity chamber. The sealing and shock-absorbing sleeve is wrapped around the middle periphery of the humidifier inlet pipe.

7. The gypsum board deflection tester according to claim 1, characterized in that, The constant temperature and humidity chamber is equipped with casters at the bottom and a push rod on one side of the outer wall.

Images