Temperature measuring device
By designing a detachable connected temperature measuring device, the problem of thermocouple wires being easily broken during multiple tests is solved, extending the service life of the device and reducing the failure rate.
Patent Information
- Application Number
- CN202420600411.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-26
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2034-03-26
AI Technical Summary
During multiple tests of the existing thermocouple temperature measuring device, the thermocouple wire is easily dragged and dropped or broken due to wrapping the material bag, resulting in the device malfunction and cannot be used.
A temperature measuring device including a housing, a first thermocouple and a second thermocouple is designed, and the detachable connection of the thermocouple is achieved through the plugging of the first connecting end and the second connecting end, avoiding pulling and wrapping of the thermocouple wires and extending the service life.
The detachable connection design avoids wear and breakage of the thermocouple wire, extends the service life of the temperature measuring device, and reduces the failure rate.
Smart Images
Figure CN222866078U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of temperature measuring equipment, for example, to a temperature measuring device. Background Art
[0002] Before leaving the factory, refrigerators need to be tested for freezing capacity and storage temperature to ensure that the refrigerator performance meets the standards and the food storage effect is good. By testing the refrigerator's freezing capacity and storage temperature, it can be verified whether the refrigerator meets the design requirements and national standards to ensure that the refrigerator can provide stable refrigeration and freezing effects in actual use and meet the user's storage needs; and the preservation of food at different temperatures can be understood to ensure the taste and nutritional value of the food. In addition, through testing and analyzing the test data, potential problems of the refrigerator can be discovered and the basis for improvement can be determined to improve the performance and operational stability of the refrigerator.
[0003] In the related art, the material package of the thermocouple temperature measuring device is integrally formed with the thermocouple wire, one end of the thermocouple wire is embedded in the material package, and the other end of the thermocouple wire extends out of the material package. The length of the thermocouple wire is 3m to 5m.
[0004] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art:
[0005] Since the material package and the thermocouple wire are integrally formed, during multiple tests, one end of the thermocouple wire embedded in the material package is easily dragged off, causing the thermocouple temperature measuring device to malfunction. After the test is completed, the thermocouple wire is wrapped around the material package for storage, which may cause the thermocouple wire to break, rendering the thermocouple temperature measuring device unusable.
[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Utility Model Content
[0007] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.
[0008] The disclosed embodiment provides a temperature measuring device to prevent the thermocouple wire from being worn or broken due to long-term pulling or bending.
[0009] In some embodiments, the temperature measuring device includes a shell, a first thermocouple and a second thermocouple; wherein the shell is filled with heat capacity material; the first thermocouple has a first connection end and a working end, the first connection end is provided with a terminal, and the working end is arranged inside the shell; the second thermocouple has a second connection end and a free end, the second connection end is provided with a plug-in terminal, and the plug-in terminal is plugged into the terminal; wherein, when the terminal is plugged into the plug-in terminal, the first thermocouple and the second thermocouple are connected in sequence to generate a thermoelectric potential difference between the free end and the working end.
[0010] In some embodiments, the first thermocouple includes a first wire and a second wire; the second thermocouple includes a third wire and a fourth wire, and when the terminal is inserted into the plug-in terminal, the third wire is connected to the first wire, and the fourth wire is connected to the second wire; the first wire and the third wire are both made of the first material, and the second wire and the fourth wire are both made of the second material.
[0011] In some embodiments, the first material is copper and the second material is copper-nickel alloy.
[0012] In some embodiments, the terminal comprises a first column and a second column, the first column is connected to the first wire, and the second column is connected to the second wire; the plug-in terminal comprises a first plug-in shell corresponding to the first column and a second plug-in shell corresponding to the second column; wherein the first column is made of the same material as the first wire, and the second column is made of the same material as the second wire; and the first plug-in shell is made of the same material as the third wire, and the second plug-in shell is made of the same material as the fourth wire.
[0013] In some embodiments, the first column and the first plug-in shell are configured as a cylindrical shape; the second column and the second plug-in shell are configured as a rectangular column shape.
[0014] In some embodiments, the shell includes a first side wall, the first side wall is recessed toward the interior of the shell to form a receiving groove, and the terminal is disposed in the receiving groove.
[0015] In some embodiments, the side wall of the accommodating groove is covered with a first protective cover shell.
[0016] In some embodiments, the second connection end is provided with a second protective cover shell that matches the shape of the first protective cover shell, the plug-in terminal is arranged in the second protective cover shell, and the second protective cover shell can be inserted into the first protective cover shell.
[0017] In some embodiments, the temperature measuring device further includes: a mounting portion, which is disposed at the working end and fixedly embedded in the interior of the heat capacity material.
[0018] In some embodiments, the mounting portion includes a metal mounting sheet or a metal mounting plate.
[0019] The temperature measuring device provided by the embodiment of the present disclosure can achieve the following technical effects:
[0020] The connection between the first thermocouple and the second thermocouple can be realized by plugging the first connection end and the second connection end, wherein the working end of the first thermocouple is arranged in the heat capacity material inside the shell, and the free end of the second thermocouple is placed in a constant temperature environment and connected to the temperature measuring instrument through a common wire. When the temperature of the free end and the working end is different, a thermoelectric potential difference is generated in the loop formed by the first thermocouple and the second thermocouple, and the temperature measuring instrument realizes the measurement of the temperature of the heat capacity material by measuring the thermoelectric potential difference.
[0021] By plugging the first connecting end and the second connecting end, the first thermocouple can be detachably connected. After the temperature measurement is completed, the second thermocouple can be easily and quickly pulled out to avoid pulling on the first thermocouple and increase the service life of the first thermocouple. The second thermocouple can also be stored separately to avoid the second thermocouple from bending, wear and even breakage due to being wrapped around the shell, thereby extending the service life of the second thermocouple. In this way, the service life of the temperature measuring device can be extended.
[0022] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:
[0024] Figure 1 is a structural schematic diagram of a first thermocouple and a shell provided in an embodiment of the present disclosure;
[0025] Figure 2 is a cross-sectional schematic diagram of a first thermocouple and a shell provided in an embodiment of the present disclosure;
[0026] Figure 3 yes Figure 2 A partial enlarged schematic diagram of
[0027] Figure 4 is a schematic structural diagram of a second thermocouple provided in an embodiment of the present disclosure;
[0028] Figure 5 It is an exploded schematic diagram of a temperature measuring device provided in an embodiment of the present disclosure.
[0029] Reference numerals:
[0030] 100, shell; 110, first side wall; 111, accommodating groove; 200, first thermocouple; 201, first wire; 202, second wire; 210, first connecting end; 220, working end; 300, second thermocouple; 301, third wire; 302, fourth wire; 310, second connecting end; 320, free end; 410, terminal; 411, first column; 412, second column; 510, first protective cover shell; 520, second protective cover shell; 600, mounting portion. DETAILED DESCRIPTION
[0031] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.
[0032] The terms "first", "second", etc. in the specification and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.
[0033] In the embodiments of the present disclosure, the terms "upper", "lower", "inside", "middle", "outside", "front", "back" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are mainly intended to better describe the embodiments of the present disclosure and their embodiments, and are not intended to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction. Moreover, in addition to being used to indicate directions or positional relationships, some of the above terms may also be used to indicate other meanings. For example, the term "upper" may also be used to indicate a certain dependency or connection relationship in certain circumstances. For those of ordinary skill in the art, the specific meanings of these terms in the embodiments of the present disclosure can be understood according to specific circumstances.
[0034] In addition, the terms "disposed", "connected", and "fixed" should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present disclosure can be understood according to specific circumstances.
[0035] Unless otherwise stated, the term "plurality" means two or more.
[0036] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B indicates: A or B.
[0037] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.
[0038] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.
[0039] Before leaving the factory, the refrigerator needs to be tested for freezing capacity and storage temperature to ensure that the refrigerator performance meets the standards and the food storage effect. By testing the refrigerator's freezing capacity and storage temperature, it can be verified whether the refrigerator meets the design requirements and national standards to ensure that the refrigerator can provide stable refrigeration and freezing effects in actual use and meet the user's storage needs; and it can understand the preservation of food at different temperatures to ensure the taste and nutritional value of the food. In addition, through testing and analyzing the test data, potential problems of the refrigerator can be discovered and the basis for improvement can be determined.
[0040] In the related art, the material bag of the thermocouple temperature measuring device is integrally formed with the thermocouple wire, one end of the thermocouple wire is embedded in the material bag, and the other end of the thermocouple wire extends out of the material bag, and the length of the thermocouple wire is 3m to 5m. However, since the material bag and the thermocouple wire are integrally formed, during multiple tests, one end of the thermocouple wire embedded in the material bag is easily dragged and dropped, causing the thermocouple temperature measuring device to malfunction. After the test is completed, the thermocouple wire is wrapped around the material bag for storage, which can also cause the thermocouple wire to break, making the temperature measuring device unusable.
[0041] Therefore, the embodiments of the present disclosure provide a temperature measuring device to prevent the thermocouple wire from being worn or broken due to long-term pulling or bending.
[0042] Combination Figures 1 to 5As shown, the temperature measuring device provided by the embodiment of the present disclosure includes a shell 100, a first thermocouple 200, and a second thermocouple 300; wherein the interior of the shell 100 is filled with a heat capacity material; the first thermocouple 200 has a first connecting end 210 and a working end 220, the first connecting end 210 is provided with a terminal 410, the working end 220 is arranged inside the shell 100, and the heat capacity material wraps the working end 220; the second thermocouple 300 includes a second connecting end 310 and a free end 320, the second connecting end 310 is provided with a plug-in terminal, and the plug-in terminal is plugged into the terminal 410; wherein, when the terminal 410 is inserted into the plug-in terminal, the first thermocouple 200 and the second thermocouple 300 are connected in sequence to generate a thermoelectric potential difference between the free end 320 and the working end 220.
[0043] When the temperature measuring device is used to test the freezing capacity and storage temperature of the refrigerator, the housing 100 is placed in the freezer or refrigerator, wherein the housing 100 is made of a heat-conducting material so as to transfer the temperature in the freezer or refrigerator to the heat-capacity material. The working end 220 of the first thermocouple 200 is disposed in the housing 100 and directly contacts the heat-capacity material so as to obtain the accurate temperature of the heat-capacity material.
[0044] The connection between the first connection end 210 and the second connection end 310 can be realized, wherein the working end 220 of the first thermocouple 200 is arranged in the heat capacity material inside the shell, and the free end 320 of the second thermocouple 300 is placed in a constant temperature environment and connected to the temperature measuring instrument through a common wire. When the temperature of the free end 320 and the working end 220 is different, a thermoelectric potential difference is generated in the loop formed by the first thermocouple 200 and the second thermocouple 300, and the temperature measuring instrument measures the temperature of the heat capacity material by measuring the thermoelectric potential difference, and can observe and record the temperature change of the heat capacity material in real time.
[0045] Optionally, the heat capacity material includes a special refrigerant, a mixture of water and ice, or other materials with similar thermal properties such as sand and soil. Among them, the selection of special refrigerants is usually based on good thermal conductivity, thermal stability and heat capacity similar to that of food to simulate the thermal properties of food during the freezing process; since the thermal conductivity and heat capacity of special refrigerants are similar to those of food, they can provide accurate test results; special refrigerants include inorganic salt refrigerants, organic compound refrigerants and mixed refrigerants; a mixture of water and ice will undergo phase change during the freezing process, which can simulate the change in thermal properties of food during freezing; sand, soil or other materials with similar thermal properties can be used to adjust the heat capacity and thermal conductivity of the M package to meet the test requirements.
[0046] By plugging the first connection end 210 and the second connection end 320, it is easy to install, connect or disassemble the first thermocouple 200 and the second thermocouple 300. After completing the temperature measurement, the second thermocouple 300 can be easily and quickly pulled out, and the pulling of the first thermocouple 200 can be avoided, reducing the failure probability of the first thermocouple 200 to increase the service life of the first thermocouple 200; at the same time, the second thermocouple 300 can also be stored separately to avoid the second thermocouple 300 from bending and causing wear or even breakage due to winding the housing, thereby extending the service life of the second thermocouple; in this way, the service life of the temperature measuring device can be extended. In addition, the second thermocouple 300 can also be replaced separately to reduce costs.
[0047] The temperature measuring device provided by the embodiment of the present disclosure can realize the connection of the first thermocouple and the second thermocouple by plugging the first connecting end and the second connecting end, wherein the working end of the first thermocouple is arranged in the heat capacity material inside the shell, and the free end of the second thermocouple is placed in a constant temperature environment and connected to the temperature measuring instrument through a common wire. When the temperature of the free end and the working end is different, a thermoelectric potential difference is generated in the loop formed by the first thermocouple and the second thermocouple, and the temperature measuring instrument realizes the measurement of the temperature of the heat capacity material by measuring the thermoelectric potential difference. By plugging the first connecting end and the second connecting end, the first thermocouple and the second thermocouple can be detachably connected. After completing the temperature measurement, the second thermocouple can be easily and quickly pulled out to avoid pulling the first thermocouple and improve the service life of the first thermocouple; and the second thermocouple can also be stored separately to avoid the second thermocouple from bending and causing wear or even breakage due to winding the shell for storage, thereby extending the service life of the second thermocouple; in this way, the service life of the temperature measuring device can be extended.
[0048] Optionally, the first thermocouple 200 includes a first wire 201 and a second wire 202; the second thermocouple 300 includes a third wire 301 and a fourth wire 302, and when the terminal 410 is inserted into the plug terminal, the third wire 301 is connected to the first wire 201, and the fourth wire 302 is connected to the second wire 202; the first wire 201 and the third wire 301 are both made of the first material, and the second wire 202 and the fourth wire 302 are both made of the second material.
[0049] The first thermocouple 200 includes a first wire 201 and a second wire 202, and correspondingly, the second thermocouple 300 includes a third wire 301 and a fourth wire 302, wherein the first end of the first wire 201 and the first end of the second wire 202 are welded and connected to form a working end of the first thermocouple 200, and the first end of the third wire 301 and the first end of the fourth wire 302 are welded and connected to form a free end 320; when the second thermocouple 300 is plugged into the first thermocouple 200, the second end of the first wire 201 and the second end of the third wire 301 are connected, and the second end of the second wire 202 and the second end of the fourth wire 302 are connected, so that when the temperatures of the free end 220 and the working end 320 are different, a thermoelectric potential difference can be formed in the loop formed after the first thermocouple 200 and the second thermocouple 300 are connected.
[0050] By making the first wire 201 and the third wire 301 both use the first material, and the second wire 202 and the fourth wire 302 both use the second material, it is possible to ensure that a thermoelectric potential difference is generated between the working end 220 and the free end 320 .
[0051] Optionally, the first material is copper and the second material is copper-nickel alloy. Copper and copper-nickel alloy are suitable for temperature measurement of -200°C to 350°C, and are therefore suitable for use in low-temperature environments such as refrigerator freezing capacity testing; and, secondly, copper and copper-nickel alloy have a faster response speed and are sensitive to low-temperature environments, which can ensure that the thermocouple can quickly and accurately capture temperature changes during the measurement process; copper and copper-nickel alloy have stable thermoelectric properties, are not easily corroded by other substances, have strong antioxidant properties, and can maintain good performance in higher temperature environments. In addition, the price of copper and copper-nickel alloy is relatively cheap, which helps to reduce the production cost of temperature measuring devices.
[0052] Optionally, the terminal 410 includes a first column 411 and a second column 412, wherein the first column 411 is connected to the first wire 201, and the second column 412 is connected to the second wire 202; the plug-in terminal includes a first plug-in shell corresponding to the first column 411 and a second plug-in shell corresponding to the second column 412; wherein the first column 411 is made of the same material as the first wire 201, and the second column 412 is made of the same material as the second wire 202; and the first plug-in shell is made of the same material as the third wire 301, and the second plug-in shell is made of the same material as the fourth wire 302. In this way, the accuracy of the temperature measurement of the heat capacity material can be guaranteed.
[0053] Optionally, the first column 411 and the first plug-in shell are configured as a cylindrical shape; the second column 412 and the second plug-in shell 512 are configured as a rectangular column shape.
[0054] Thus, by identifying the first column 411 and the first plug shell, the second column 412 and the second plug shell 512 of the same shape, the accuracy of the connection between the first wire 201 and the third wire 301 and the accuracy of the connection between the second wire 202 and the fourth wire 302 can be ensured.
[0055] Optionally, the housing 100 includes a first side wall 110 , the first side wall 110 is recessed toward the inside of the housing 100 to form an accommodating groove 111 , and the terminal 410 is disposed in the accommodating groove 111 .
[0056] In this way, the depression of the accommodating groove 111 can be utilized to protect the terminal 410 , thereby preventing the terminal 410 from being bent or broken under the action of external force, thereby improving the safety of the first thermocouple 200 .
[0057] Optionally, the side wall of the accommodating groove 111 is covered with a first protective cover shell 510 .
[0058] The housing 100 can be isolated from the terminal 410 by the first cover to reduce the influence of the temperature of the housing 100 on the first connection end 210. Optionally, the first protective cover 510 is made of insulating material to reduce heat loss at the plug-in position to ensure the accuracy of temperature measurement after the first thermocouple 200 and the second thermocouple 300 are plugged in.
[0059] Optionally, the second connection end 310 is provided with a second protective cover 520 matching the shape of the first protective cover 510 or the accommodating groove 111 , the plug-in terminal is arranged in the second protective cover 520 , and the second protective cover 520 can be inserted into the first protective cover 510 or the accommodating groove 111 .
[0060] When the second protective cover 520 is inserted into the first protective cover 510 , the terminal 410 is inserted into the plug-in terminal, so that the stability and safety of the connection between the first thermocouple 200 and the second thermocouple 300 can be improved.
[0061] Optionally, the second protective cover 520 is made of insulating material to reduce heat loss at the plug-in position, so as to ensure the accuracy of temperature measurement after the first thermocouple 200 and the second thermocouple 300 are plugged in.
[0062] Optionally, the accommodating groove 111 includes a first side wall and a second side wall relative to each other, wherein the first side wall is close to the first column 411, and the second side wall is close to the second column 412, the first side wall is constructed as an arc-shaped side wall, and the side edges of the first protective cover shell 510 and the second protective cover shell 520 corresponding to the first side wall are also constructed as arcs, so as to distinguish the direction of the first column 411 and the first wiring shell, and the direction of the second column 412 and the second wiring shell, thereby ensuring the accuracy of the connection between the first wire 201 and the third wire 301, and the accuracy of the connection between the second wire 202 and the fourth wire 302.
[0063] Optionally, the temperature measuring device further includes a mounting portion 600. The mounting portion 600 is disposed at the working end 220 and is fixedly embedded in the interior of the heat capacity material.
[0064] The working end 220 is disposed on the mounting portion 600 , and after the mounting portion is fixed at a preset position in the shell 100 , the shell is filled with heat capacity material to fix the working end 220 , thereby ensuring that the working end 220 is disposed at the preset position.
[0065] Optionally, the mounting portion 600 includes a metal mounting sheet or a metal mounting plate.
[0066] In this way, by providing a metal mounting sheet or a metal mounting plate, the heat around the mounting portion 600 can be quickly transferred to the working end to ensure the accuracy of the temperature measuring device.
[0067] The above description and the accompanying drawings sufficiently illustrate the embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Portions and features of some embodiments may be included in or replace portions and features of other embodiments. The embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.
Claims
1. A temperature measuring device, characterized in that: include: A shell body, the interior of which is filled with a heat capacity material; A first thermocouple, comprising a first connection end and a working end, wherein the first connection end is provided with a terminal, and the working end is arranged inside the housing; A second thermocouple has a second connection end and a free end, the second connection end is provided with a plug-in terminal, and the plug-in terminal is plug-matched with the terminal post; Wherein, when the terminal block is inserted into the plug-in terminal, the first thermocouple and the second thermocouple are connected in sequence to generate a thermoelectric potential difference between the free end and the working end.
2. The temperature measuring device according to claim 1, characterized in that: The first thermocouple includes a first wire and a second wire; The second thermocouple includes a third wire and a fourth wire, and when the terminal is inserted into the plug-in terminal, the third wire is connected to the first wire, and the fourth wire is connected to the second wire; The first wire and the third wire are both made of the first material, and the second wire and the fourth wire are both made of the second material.
3. The temperature measuring device according to claim 2, characterized in that: The first material is copper, and the second material is copper-nickel alloy.
4. The temperature measuring device according to claim 2, characterized in that: The terminal comprises a first column and a second column, the first column is connected to the first wire, and the second column is connected to the second wire; The plug-in terminal comprises a first plug-in shell corresponding to the first column and a second plug-in shell corresponding to the second column; The first column is made of the same material as the first wire, and the second column is made of the same material as the second wire; and the first plug-in shell is made of the same material as the third wire, and the second plug-in shell is made of the same material as the fourth wire.
5. The temperature measuring device according to claim 4, characterized in that: The first column and the first plug-in shell are configured as a cylinder; The second column and the second plug-in housing are configured in a rectangular column shape.
6. The temperature measuring device according to claim 1, characterized in that: The shell comprises a first side wall, the first side wall is recessed toward the inside of the shell to form an accommodating groove, and the terminal is arranged in the accommodating groove.
7. The temperature measuring device according to claim 6, characterized in that: The side wall of the accommodating groove is covered with a first protective cover shell.
8. The temperature measuring device according to claim 7, characterized in that: The second connection end is provided with a second protective cover shell which matches the shape of the first protective cover shell, the plug-in terminal is arranged in the second protective cover shell, and the second protective cover shell can be inserted into the first protective cover shell.
9. The temperature measuring device according to any one of claims 1 to 8, characterized in that: Also includes: The mounting portion is arranged at the working end and is fixedly embedded in the interior of the heat capacity material.
10. The temperature measuring device according to claim 9, characterized in that: The mounting portion includes a metal mounting sheet or a metal mounting plate.