Temperature history estimation device, temperature history estimation method and temperature history estimation procedure

Abstract

The temperature history of a rubber composition is estimated using a simple method. The temperature history estimation device (1) estimates the temperature history of the rubber composition being measured. The temperature history estimation device (1) includes: a measurement value receiving unit (101) that receives the measurement value of the carbonization rate of the polymer contained in the sample being measured; a storage unit (20) that stores data (202) showing the relationship between the carbonization rate of the polymer contained in the sample of the rubber composition and temperature; and a temperature history estimation unit (102) that estimates the temperature history of the sample being measured based on the measurement value of the carbonization rate and the data (202).

Description

Technical Field

[0001] This invention relates to a temperature history estimation device, a temperature history estimation method, and a temperature history estimation procedure. Background Technology

[0002] In the past, for rubber compositions, the degree of deterioration was estimated by measuring structural changes or rubber hardness changes using FT-IR (for example, see Non-Invention Patent Document 1).

[0003] Existing technical documents

[0004] Non-invention patent literature

[0005] Non-invention patent document 1: Tetsuya Kawashima and Toshio Ogawa, “Damage Caused by Thermal Deterioration of NBR”, Japan Rubber Association Magazine, Vol. 75, No. 6, 2002, pp. 257-262. Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] However, because these changes are difficult to quantify and have large errors, it is difficult to accurately estimate the temperature history of a sample of rubber composition.

[0008] The present invention was made in view of the above-mentioned problems, and its object is to provide a technique for estimating the temperature history of a rubber composition by a simple method.

[0009] Methods for solving problems

[0010] To achieve the above objective, the temperature history estimation apparatus of the present invention is an apparatus for estimating the temperature history of a rubber composition as a test object, comprising: a measurement value receiving unit that receives a measurement value of the carbonization rate of a polymer contained in the test object; a storage unit that stores data representing the relationship between the carbonization rate of the polymer contained in a sample of the rubber composition and temperature; and a temperature history estimation unit that estimates the temperature history of the test object based on the measurement value of the carbonization rate and the data.

[0011] In a temperature history estimation apparatus according to one aspect of the present invention, the temperature history estimation unit establishes a correspondence between the measured value of carbonization rate and the carbonization rate of polymer contained in the sample in the data, and estimates the temperature history of the measured object.

[0012] In one aspect of the present invention, the measured value of carbonization rate is determined using a thermogravimetric differential thermal analysis device.

[0013] To achieve the above objective, the temperature history estimation method of the present invention is a method for estimating the temperature history of a rubber composition as a test object, comprising the following steps: receiving a measured value of the carbonization rate of the polymer contained in the test object; and estimating the temperature history of the test object based on the measured value of the carbonization rate and data representing the relationship between the carbonization rate of the polymer contained in the sample of the rubber composition and temperature.

[0014] To achieve the above objectives, the temperature history estimation procedure involved in this invention is a procedure executed by a computer to estimate the temperature history of a test object, which is a rubber composition. The computer performs the following steps: receiving a measured value of the carbonization rate of the polymer contained in the test object; and estimating the temperature history of the test object based on the measured value of the carbonization rate and data representing the relationship between the carbonization rate of the polymer contained in the sample of the rubber composition and temperature.

[0015] In one aspect of the present invention, in the method and procedure for estimating temperature history, in the step of estimating the temperature history of the object to be measured, the measured value of carbonization rate is correlated with the carbonization rate of the polymer contained in the sample in the data, thereby estimating the temperature history of the object to be measured.

[0016] In one aspect of the present invention, the temperature history estimation method and procedure involve measuring the carbonization rate using a thermogravimetric differential thermal analysis device.

[0017] The effects of the invention

[0018] The temperature history estimation device, method, and procedure of the present invention enable the estimation of the temperature history of a rubber composition in a simple manner. Attached Figure Description

[0019] Figure 1 This is a functional block diagram of the temperature history estimation device involved in the embodiments of the present invention.

[0020] Figure 2 This is a cross-sectional perspective view of a gear damper with a rubber composition, which uses the temperature history estimation device according to this embodiment to estimate the temperature history.

[0021] Figure 3 This is a schematic diagram showing an example of a screen displayed in the notification section where the measurement value receiving unit of the temperature history estimation device according to this embodiment receives the measurement value of the carbonization rate.

[0022] Figure 4This is a graph showing the TG-DTA curve of the rubber composition for temperature history estimation using the temperature history estimation device according to this embodiment.

[0023] Figure 5 This is a schematic diagram used to illustrate the deterioration principle of a rubber composition.

[0024] Figure 6 This is a graph showing the relationship between the carbonization rate of the polymer in the rubber composition and the temperature history when the temperature history is estimated using the temperature history estimation device according to this embodiment.

[0025] Figure 7 It is a graph showing the relationship between the change in rubber hardness in a rubber composition and temperature history.

[0026] Figure 8 This is a graph showing the relationship between the FT-IR of a rubber composition and its temperature history.

[0027] Figure 9 This is a schematic diagram showing an example of a screen displayed in the notification section, displaying the estimated result of the temperature history calculated based on the measured value by the temperature history estimation unit in the temperature history estimation device according to this embodiment.

[0028] Figure 10 This is a flowchart illustrating the temperature history estimation method performed by the temperature history estimation device involved in this embodiment.

[0029] Symbol Explanation

[0030] 1 Temperature history estimation device

[0031] 2 Gear shock absorbers

[0032] 3. Rubber ring

[0033] 10. Data Processing and Control Department

[0034] 20 Storage Department

[0035] 30 Operations Department

[0036] 40 Notification Department

[0037] 50 Interface Section

[0038] 101 Measurement Receiving Section

[0039] 102 Temperature History Estimation Department

[0040] 201 Temperature History Estimation Procedure

[0041] 202 Temperature Sample Data

[0042] 203 Temperature History Estimation Results

[0043] 210 and 211 TG-DTA curves

[0044] 300 Measurement Value Receiving Screen

[0045] 301 Measurement Input Section

[0046] 310 Temperature History Estimation Results Display Screen

[0047] 311 Presumed Results Display Section Detailed Implementation

[0048] The embodiments of the present invention will now be described with reference to the accompanying drawings.

[0049] Figure 1 This is a functional block diagram of the temperature history estimation device 1 according to an embodiment of the present invention.

[0050] like Figure 1 As shown, the temperature history estimation device 1 involved in the embodiment of the present invention is an information processing device, such as a PC (personal computer), smartphone, or tablet terminal, which has a data processing control unit 10 and a storage unit 20.

[0051] The data processing control unit 10 is composed of an information processing device capable of executing computer programs, including a processor such as a CPU (Central Processing Unit) and a storage device such as an MCU (Micro Controller Unit). The storage device included in the data processing control unit 10 is implemented using known storage devices (storage media) such as ROM, RAM, and flash memory.

[0052] The data processing control unit 10 is a functional unit that comprehensively controls each functional unit in the temperature history estimation device 1. As described above, the data processing control unit 10 is configured to include, for example, a processor such as a CPU. The data processing control unit 10 controls each functional unit in the temperature history estimation device 1 by performing various calculations according to a program stored in the storage unit 20.

[0053] Storage unit 20 is a non-volatile storage device that stores various types of information described later, such as a magnetic storage device like a hard disk drive or an electrical storage device like a solid-state drive.

[0054] The storage unit 20 stores various programs for enabling the information processing device to function as a temperature history estimation device 1. Among the various programs stored in the storage unit 20 is the temperature history estimation program 201 according to the present invention. Additionally, the storage unit 20 stores data (hereinafter referred to as "carbonization rate-temperature sample data 202") showing the relationship between the carbonization rate of the polymer contained in a sample of a rubber composition and temperature, wherein the rubber composition has a composition corresponding to the object of measurement used in the calculation for estimating the temperature history of the object to be measured. Furthermore, the storage unit 20 is a functional unit for storing various data such as temperature history estimation results 203.

[0055] The operation unit 30 is the input interface for the user to operate the temperature history estimation device 1. Examples of the operation unit 30 include various buttons, keyboards, pointing devices, and touch panels. For instance, by operating the operation unit 30, the user can set various conditions for estimating the temperature history of the object being measured in the temperature history estimation device 1, and instruct the temperature history estimation device 1 to execute and stop the temperature history estimation process. Furthermore, the operation unit 30 is not limited to the aforementioned buttons or touch panels; it can be any unit capable of receiving user input for operating the temperature history estimation device 1. The operation unit 30 may also receive operations via voice-based command input, for example.

[0056] The notification unit 40 is a functional unit that notifies the user of various information, such as the determination of the measurement object in the temperature history estimation device 1, the name of the carbonization rate-temperature sample data 202 used in the temperature history estimation process, or the confirmation of stored data, estimation conditions, and estimation results. The notification unit 40 may be, for example, a display device equipped with an LCD (Liquid Crystal Display) or an organic EL display. Alternatively, the notification unit 40 may be a device that outputs sound data to notify the user, such as a speaker or headphones. Furthermore, the notification unit 40 may also be a display device equipped with a touch panel that performs functions as part of the operation unit 30.

[0057] The interface unit 50 comprises various interfaces capable of inputting and outputting data between the temperature history estimation device 1 and an external device (not shown). The interface unit 50 may be, for example, a LAN, USB, RS-232C, or other communication interfaces. Through the interface unit 50, the temperature history estimation device 1 can input and output data via the aforementioned external device. The interface unit 50 may also include communication circuitry for outputting various data used in temperature history estimation to an external device via wired or wireless means. Through these various communication interfaces, the temperature history estimation device 1 can, for example, communicate with a wide area network (WAN) or a local area network (LAN), such as the Internet.

[0058] The temperature history estimation device 1 has the above-described hardware configuration. The data processing control unit 10 executes the temperature history estimation program stored in the storage unit 20, and the hardware and software work together to estimate the temperature history of the rubber composition being measured. As a functional block implemented by the temperature history estimation program, the temperature history estimation device 1 includes a measured value receiving unit 101, the aforementioned storage unit 20, and a temperature history estimation unit 102.

[0059] Figure 2 This is a cross-sectional perspective view of a gear damper 2 with a rubber composition, used in the temperature history estimation device 1 according to this embodiment to estimate the temperature history. In this embodiment, the temperature history estimation device 1 estimates the temperature value, i.e., the temperature history, of a rubber composition, such as a rubber ring 3 provided on the gear damper 2, by measuring the carbonization rate of the polymer contained in the rubber composition, such as hydrogenated nitrile butadiene rubber (HNBR).

[0060] Furthermore, the rubber composition used as the object of measurement for the estimation process based on the temperature history of the temperature history estimation device 1 is not limited to... Figure 2 The rubber composition shown can be used in various rubber products, such as gear dampers or torsion dampers.

[0061] The measurement value receiving unit 101 receives the measurement value (hereinafter referred to as "measured value") of the carbonization rate of the polymer contained in the test object. The measured value is determined using a thermogravimetry-differential thermal analysis (TG-DTA) device, which is a device that simultaneously performs thermogravimetric analysis and differential thermal analysis. Specifically, based on the amount of weight loss of the rubber in the combustion zone (in air, approximately 450–550°C), the amount of carbonization of the rubber due to structural changes caused by temperature history is measured.

[0062] Figure 3 This is a schematic diagram showing an example of a measurement value receiving screen 300 displayed in the notification unit 40, where the measurement value receiving unit 101 in the temperature history estimation device 1 according to this embodiment receives the input of the measurement value of carbonization rate. The measurement value receiving screen 300 is displayed, for example, on the components of the notification unit 40 (see reference 100). Figure 1 The measurement value is displayed on the device. For example, the user can input the measurement value into the measurement value input unit 301 on the measurement value receiving screen 300 via the operation unit 30 or the interface unit 50. The measurement value input into the measurement value input unit 301 is received by the measurement value receiving unit 101. In addition, the method of inputting the measurement value is not limited to the above example.

[0063] The temperature history estimation unit 102 estimates the temperature history of the object being measured based on the measured values ​​received by the measured value receiving unit 101 and the carbonization rate-temperature sample data 202 stored in the storage unit 20. Specifically, the temperature history estimation unit 102 establishes a correspondence between the measured carbonization rate received by the measured value receiving unit 101 and the carbonization rate of the polymer contained in the sample in the carbonization rate-temperature sample data 202, and estimates the temperature history of the object being measured.

[0064] Figure 4 This is a graph showing the TG-DTA curve of the rubber composition for temperature history estimation using the temperature history estimation device 1 according to this embodiment. Figure 4 In the graph, the left vertical axis represents the weight loss rate (wt%), the right vertical axis represents temperature (°C), and the horizontal axis represents time (minutes). Figure 4 The diagram shows a TG-DTA curve 210 for a virgin rubber composition (not exposed to a high-temperature environment) and a TG-DTA curve 211 for a rubber composition subjected to a specified temperature (e.g., 150°C). In this embodiment, the rubber composition used in a high-temperature environment is the rubber composition that serves as the object of estimation of temperature history, i.e., the object of measurement.

[0065] Figure 5 This is a schematic diagram used to illustrate the deterioration principle of a rubber composition. From Figure 4 The TG-DTA curve 210 of the new rubber composition and the TG-DTA curve 211 of the rubber composition subjected to heat at a specified temperature show that the weight percentage of carbides (carbon precursors) in the rubber composition increases by using it at high temperatures. Then, as... Figure 5 As shown, it is estimated that the polymer in rubber compositions such as HNBR cyclizes and deteriorates into carbides (carbon precursors) in a high-temperature environment. Therefore, in the temperature history estimation device 1, the temperature history of the test object is estimated based on the carbonization rate of the polymer contained in the test object of the rubber composition.

[0066] Figure 6This is a graph showing the relationship between the carbonization rate of the polymer in the rubber composition and the temperature history when the temperature history is estimated using the temperature history estimation device 1 according to this embodiment. Figure 6 In the graph, the vertical axis represents the carbonization rate of the polymer (%), and the horizontal axis represents the temperature history of the rubber composition (°C). For example... Figure 6 As shown, in the rubber composition for which temperature history is estimated using temperature history estimation device 1, the following relationship exists: as the carbonization rate of the polymer increases, the temperature shown in the temperature history of the rubber composition containing the polymer also increases. That is, it can be seen that in a rubber composition, if the carbonization rate of the polymer can be measured, the temperature history experienced by the rubber composition can be estimated. In such a graph showing the relationship between the carbonization rate of the polymer and the temperature history, line L1 represents the specified temperature and carbonization rate used as a benchmark for judging the deterioration of the rubber composition. It can be seen that any number of points depicted in the graph, for example... Figure 5 Point P4, which exceeds line L1, represents the temperature history exceeding the aforementioned specified temperature.

[0067] Figure 7 This is a graph showing the relationship between the change in rubber hardness in a rubber composition and temperature history. Additionally, Figure 8 This is a graph showing the relationship between the FT-IR of a rubber composition and its temperature history.

[0068] In use Figure 7 Evaluation and application of rubber hardness changes shown Figure 8 In the FT-IR (Fourier Transform-Infrared Spectroscopy) evaluation shown, there are significant discrepancies between the values ​​measured from the rubber composition and the temperature history experienced by the rubber composition. Therefore, it is difficult to use changes in rubber hardness and FT-IR to estimate the temperature history of the rubber composition. Furthermore, when estimating temperature history based on structural changes according to FT-IR, the measured values ​​cannot capture structural changes at high temperatures, making standardization difficult.

[0069] Therefore, the temperature history estimation device 1 stores the combination of the temperature history value pre-measured from a sample of a rubber composition having the same composition as the object being measured and the carbonization rate of the polymer in that temperature history as carbonization rate-temperature sample data 202 in the storage unit 20. The carbonization rate-temperature sample data 202 is stored in the storage unit 20, for example, according to the type of rubber composition. In the carbonization rate-temperature sample data 202, a temperature history corresponding to the carbonization rate can be established in the storage unit 20 at any interval (step size), such as every 20°C of temperature history or every 5% of carbonization rate.

[0070] Then, the temperature history estimation device 1 determines the temperature history value corresponding to the measured value of carbonization received from the measurement value receiving unit 101 based on the carbonization rate-temperature sample data 202 stored in the storage unit 20. Thus, the temperature history estimation device 1 can estimate the temperature history of the rubber composition by measuring the carbonization rate of the polymer in the rubber composition.

[0071] Figure 9 This is a schematic diagram illustrating an example of a temperature history estimation result display screen 310 displayed on the notification unit 40, showing the estimated temperature history calculated based on measured values ​​by the temperature history estimation unit 102 in the temperature history estimation device 1 according to this embodiment. The temperature history estimation result display screen 310 is displayed, for example, on a display device constituting the notification unit 40. The user can identify the estimated temperature history result by checking the values ​​displayed on the estimation result display unit 311 in the temperature history estimation result display screen 310. Furthermore, the method of displaying and outputting the estimated temperature history result is not limited to the example described above.

[0072] Figure 10 This is a flowchart illustrating the temperature history estimation method performed by the temperature history estimation device 1 according to this embodiment.

[0073] First, in the temperature history estimation device 1, the measurement value receiving unit 101 receives the input of the measurement value of the carbonization rate of the polymer of the object to be measured from the operation unit 30 or the interface unit 50 (step S101).

[0074] The temperature history estimation unit 102 retrieves the carbonization rate-temperature sample data 202 of the rubber composition with the same composition as the measured object, which is received by the measurement value receiving unit 101 and is stored in the storage unit 20 (step S102).

[0075] The temperature history estimation unit 102 determines whether there is carbonization rate-temperature sample data 202 corresponding to the measured value of the object being measured in the storage unit 20 (step S103). If there is no carbonization rate-temperature sample data 202 corresponding to the storage unit 20 (S103: No), the temperature history estimation unit 102 notifies the user via the notification unit 40 to request the saving of the corresponding carbonization rate-temperature sample data 202 (step S104). After S104, the temperature history estimation unit 102 returns to the processing of S102.

[0076] If carbonization rate-temperature sample data 202 corresponding to storage unit 20 exists (S103: Yes), temperature history estimation unit 102 estimates the temperature history of the object to be measured based on the measured value of the object and the carbonization rate-temperature sample data 202 (step S105).

[0077] The temperature history estimation unit 102 determines whether the temperature history estimation process of the object being measured is complete by establishing a correspondence between the measured value of the object and the carbonization rate value in the carbonization rate-temperature sample data 202 (step S106). If the temperature history estimation process of the object being measured is not complete (S106: No), the temperature history estimation unit 102 notifies the notification unit 40 of an error message indicating that the temperature history estimation process is not complete (step S107) and returns to the processing in S101.

[0078] When the process of estimating the temperature history of the object being measured is completed (S106: Yes), the temperature history estimation unit 102 outputs the estimated value of the temperature history of the object being measured from the notification unit 40 (step S108). After the processing of S108, the temperature history estimation device 1 ends the process.

[0079] As described above, in the temperature history estimation apparatus 1 according to this embodiment, by executing the temperature history estimation program, a temperature history estimation method can be executed to estimate the temperature history of the rubber composition based on the carbonization rate measurement value of the polymer contained in the rubber composition of the test object.

[0080] Specifically, in the temperature history estimation method performed by the temperature history estimation apparatus 1 according to this embodiment, the focus is on the carbon precursors that occur when the rubber (NBR) deteriorates and its structure changes. Furthermore, in the temperature history estimation method, the amount of carbon precursors, i.e., the carbonization rate of the polymer, is measured using TG-DTA, and the temperature history of the measured object is estimated based on the relationship between this carbonization rate and the temperature history. Here, the temperature history of the rubber composition can be used as an indicator of the degree of deterioration. Compared with FT-IR or rubber hardness changes, TG-DTA values ​​show smaller errors in their relationship with temperature history. In addition, compared with FT-IR or rubber hardness changes, TG-DTA can be easily quantified.

[0081] Therefore, the temperature history estimation method executed by the temperature history estimation device 1 can easily estimate the temperature history of the rubber composition.

[0082] The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments described above, and includes all the concepts of the present invention and all the embodiments contained in the claims. Furthermore, the various structures can be selectively combined appropriately to achieve at least a portion of the above-described effects. For example, the shape, material, arrangement, size, etc., of each constituent element in the above embodiments can be appropriately modified according to the specific usage of the present invention.

Claims

1. A temperature history estimation device that is a device that estimates a temperature history of a measurement target that is a rubber composition, comprising: a measurement value receiving section that receives a measurement value of a carbonization rate of a polymer contained in the measurement target; a storage section that stores data indicating a relationship between a carbonization rate of a polymer contained in a sample of the rubber composition and a temperature; and a temperature history estimation section that estimates a temperature history of the measurement target based on the measurement value of the carbonization rate and the data.

2. The temperature history estimation device according to claim 1, wherein the temperature history estimation section corresponds the measurement value of the carbonization rate to a carbonization rate of a polymer contained in a sample in the data, and estimates the temperature history of the measurement target.

3. The temperature history estimation device according to claim 1 or 2, wherein the measurement value of the carbonization rate is measured using a thermogravimetric differential thermal analysis device.

4. A temperature history estimation method that is a method of estimating a temperature history of a measurement target that is a rubber composition, comprising: a step of receiving a measurement value of a carbonization rate of a polymer contained in the measurement target; and a step of estimating a temperature history of the measurement target based on the measurement value of the carbonization rate and data indicating a relationship between a carbonization rate of a polymer contained in a sample of the rubber composition and a temperature.

5. The temperature history estimation method according to claim 4, wherein in the step of estimating the temperature history of the measurement target, the measurement value of the carbonization rate is corresponded to a carbonization rate of a polymer contained in a sample in the data, and the temperature history of the measurement target is estimated.

6. The temperature history estimation method according to claim 4 or 5, wherein the measurement value of the carbonization rate is measured using a thermogravimetric differential thermal analysis device.

7. A storage medium that stores a temperature history estimation program that is a program that causes a computer to execute a process of estimating a temperature history of a measurement target that is a rubber composition, causing the computer to execute: a step of receiving a measurement value of a carbonization rate of a polymer contained in the measurement target; and a step of estimating a temperature history of the measurement target based on the measurement value of the carbonization rate and data indicating a relationship between a carbonization rate of a polymer contained in a sample of the rubber composition and a temperature.

8. The storage medium according to claim 7, wherein in the step of estimating the temperature history of the measurement target, the measurement value of the carbonization rate is corresponded to a carbonization rate of a polymer contained in a sample in the data, and the temperature history of the measurement target is estimated.

9. The storage medium according to claim 7 or 8, wherein the measurement value of the carbonization rate is measured using a thermogravimetric differential thermal analysis device. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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