WO2023125141A1

WO2023125141A1 - Terminal temperature measurement structure

Info

Publication number: WO2023125141A1
Application number: PCT/CN2022/140301
Authority: WO
Inventors: 王超
Original assignee: 长春捷翼汽车科技股份有限公司
Priority date: 2021-12-27
Filing date: 2022-12-20
Publication date: 2023-07-06
Also published as: CN217211164U

Abstract

The present invention belongs to the technical field of the manufacturing of electric energy transmission apparatuses. Disclosed is a terminal temperature measurement structure. The terminal temperature measurement structure comprises a conductive terminal, a heat conduction member and a temperature sensor, wherein the conductive terminal is provided with a groove; at least part of the heat conduction member is arranged in the groove; and the temperature sensor is in thermal connection with the heat conduction member. The temperature sensor is arranged in the groove, such that the area of a region, where the temperature is collected by the temperature sensor, of the conductive terminal can be increased, which is more stable, and a temperature signal collected by the temperature sensor is closer to an actual temperature change and has a smaller error. The heat conduction member is in the shape of a circular arc and is fitted with the circumferential groove, so as to be conveniently mounted on the conductive terminal, and a locking ring is additionally provided, such that a tighter fit is realized between the heat conduction member and the circumferential groove, and thus the measured temperature is closer to a true value.

Description

A terminal temperature measurement structure

This application claims the priority of the Chinese patent application with the application number 202123309604.9 and the title of the invention "a terminal temperature measurement structure" submitted on December 27, 2021, the entire content of which is incorporated in this application by reference.

technical field

The invention belongs to the technical field of electric energy transmission device manufacturing, and in particular relates to a terminal temperature measuring structure.

Background technique

With the rapid development of new energy technology, the number of new energy vehicles is also increasing. At present, the charging gun head and the charging stand of new energy vehicles will have a charging terminal with a plug-in structure, and the charging terminal is fixed on the charging gun head or the terminal card seat of the charging stand. When the car is charging, the current at the charging terminal increases rapidly, and the calorific value rises sharply. Therefore, for safety reasons, many manufacturers will install a temperature measuring device at the charging terminal. There are many ways to measure temperature, only from whether the measuring body is in contact with the measured medium. There are two types of contact measurement and non-contact temperature measurement. The temperature measurement element must be in contact with the measured medium before the temperature can be measured. , When the measured medium is inaccessible or has major hidden dangers after contact, contact temperature measurement cannot be selected. Non-contact temperature measurement, because the temperature measurement element is not in contact with the measured medium, so its temperature measurement range is very wide, and its upper limit of temperature measurement is not limited in principle, but non-contact temperature measurement is subject to the emissivity of the object, the measured The distance from the object to the temperature measuring element, the influence of other media such as smoke and water vapor, the general temperature measurement error is large, and the heat is transferred through radiation heat, the reaction time is long, and the temperature measurement speed is slow, which cannot meet many requirements. and accuracy cases. Contact temperature measurement is simple, reliable and has high measurement accuracy. But in many cases, the contact area between the sensor and the charging terminal is not enough, so that the measured value is not accurate enough, and there is also the problem of inconvenient connection between the sensor and the charging terminal. Therefore, a new solution is urgently needed in the prior art to solve the above problems.

Contents of the invention

The purpose of the present invention is to provide a terminal temperature measurement structure, which can reduce the error caused by temperature detection by increasing the contact area and improving the installation process, so as to ensure charging safety.

The invention discloses a terminal temperature measuring structure, which comprises: a conductive terminal, a heat conducting part and a temperature sensor;

Grooves are arranged on the conductive terminals;

The heat conducting element is at least partially disposed in the groove;

The temperature sensor is thermally connected with the heat conducting element.

In some embodiments, the conductive terminal is cylindrical, the groove is a circumferential groove provided on the conductive terminal, and the heat conduction member has a contact surface matching the circumferential groove.

Further, the contact surface is an arc surface.

In some embodiments, the degree of arc of the arc surface is 36°-180°.

In some embodiments, a locking ring is further provided in the circumferential groove, and the locking ring cooperates with the heat conducting element to fix the heat conducting element in the circumferential groove.

In some embodiments, the conductive terminal includes a connecting portion, and the circumferential groove is disposed on the connecting portion.

In some embodiments, the contact surface between the heat conduction member and the groove is provided with heat conduction silica gel.

In some embodiments, the temperature sensor is an NTC temperature sensor, a PTC temperature sensor or a bimetallic temperature sensor.

In some embodiments, the material of the heat conduction element includes heat conduction ceramics.

In some embodiments, the thermal resistance of the heat conducting element is less than 12K·cm2/W.

In some embodiments, the heat conduction time of the heat conduction element is less than 20ms.

The beneficial effects of the present invention are: the arrangement of the heat conduction element in the groove can increase the lamination area between the heat conduction element and the conductive terminal, making it more stable, and the temperature signal collected by the temperature sensor is closer to the actual temperature change, with smaller error.

The heat conduction part is arc-shaped and fits with the circumferential groove for easy installation on the conductive terminal, and the locking ring is added to make the heat conduction part and the circumferential groove fit closer, and the measured temperature is closer to the real value.

Thermally conductive silica gel can assist the connection between conductive terminals and heat-conducting parts, increase the effective contact area between conductive terminals and heat-conducting parts, increase adhesion, and avoid the reduction of effective contact area caused by vibration and the reduction of heat conduction efficiency due to air gaps.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

Fig. 1 is a structural schematic diagram of a terminal temperature measuring structure of the present invention.

Fig. 2 is a structural schematic diagram of a heat conducting member and a temperature sensor of a terminal temperature measuring structure according to the present invention.

Fig. 3 is a structural schematic diagram of a circumferential groove of a terminal temperature measuring structure according to the present invention.

Fig. 4 is a structural schematic diagram of a locking ring of a terminal temperature measuring structure according to the present invention.

The diagram is marked as follows:

1. Conductive terminal; 11. Circumferential groove; 2. Heat conducting member; 21. Arc surface; 3. Temperature sensor; 4. Locking ring.

Detailed ways

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and in no way taken as limiting the invention, its application or uses.

Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the description.

In all examples shown and discussed herein, any specific values should be construed as exemplary only, and not as limitations. Therefore, other instances of the exemplary embodiment may have different values.

A terminal temperature measurement structure, as shown in Figures 1-3, comprising: a conductive terminal 1, a heat conducting member 2 and a temperature sensor 3;

The conductive terminal 1 is provided with grooves;

The heat conducting element 2 is at least partially disposed in the groove;

The temperature sensor 3 is thermally connected with the heat conducting element 2 .

In a traditional terminal temperature measurement method, the temperature sensor 3 is generally directly connected to the terminal to measure the temperature of the terminal. However, it is difficult for the temperature sensor 3 to fully fit the terminal, resulting in a large error between the measured temperature and the actual temperature of the terminal. However, in the solution proposed by the present invention, a groove is provided on the conductive terminal 1 , and a heat conduction member 2 is arranged in the groove, and the heat conduction member 2 is connected to the temperature sensor 3 . The heat conduction element 2 is partly arranged in the groove, and can fully contact the conductive terminal 1, and the size of the heat conduction element 2 and the groove can be designed according to needs to adjust the contact area between the heat conduction element 2 and the conduction terminal 1. By making the temperature of the heat conducting member 2 and the conductive terminal 1 tend to be consistent, the temperature value obtained by the temperature sensor 3 will be more accurate. A recess can be provided on the heat conducting member 2 for accommodating the temperature sensor 3 to increase the accuracy of the temperature sensor 3 .

In some embodiments, the conductive terminal 1 is cylindrical, and the groove is a circumferential groove 11 provided on the conductive terminal 1. As shown in FIG. Matching contact surfaces. The contact surface fits inside the circumferential groove 11 of the conductive terminal 1 , so that the temperature value of the conductive terminal 1 can be accurately measured.

Further, the contact surface is an arc surface 21 . The circumferential groove 11 is in the shape of a ring, and the heat conduction element 2 with the arc surface 21 is more stably connected to the circumferential groove 11 and can also reduce the occupied space.

In some embodiments, the degree of arc of the arc surface 21 is 36°-180°. If the degree of arc is too small, the contact area between the heat-conducting member 2 and the conductive terminal 1 is too small, and the measured temperature value is inaccurate. In order to select the most suitable degree of arc for the arc surface 21, the inventor conducted related experiments and selected the same Each conductive terminal 1 has the same circumferential groove 11, select the heat-conducting member 2 with the same radius and different degrees of arc, measure the temperature of the conductive terminal 1, and take the absolute value of the difference from the actual temperature. Values greater than 0.5°C are unqualified, and the results are recorded in Table 1.

Table 1: The influence of the arc degree of the arc surface on the temperature measurement effect

It can be seen from Table 1 that when the degree of arc of the arc surface 21 is less than 36°, the temperature difference between the measured temperature and the actual temperature exceeds 0.5°C, which is unqualified. When the degree of arc of the arc surface 21 is greater than or equal to 36° The temperature difference between the actual temperature and the same temperature is within 0.5°C, which is qualified. When the degree of arc reaches 180°, there is no difference between the measured temperature and the actual temperature. Therefore, the inventor prefers the degree of arc to be 180°, that is to say, the arc surface 21 is ideally a semicircle. And when the degree of arc is greater than 180°, the opening of the heat conduction member 2 is smaller than the diameter of the groove 11 provided on the conductive terminal 1, and it cannot be installed. Therefore, the arc degree of the arc surface 21 chosen by the inventor is 36°- 180°.

In some embodiments, a locking ring 4 is also provided in the circumferential groove 11, and the locking ring 4 cooperates with the heat conducting element 2 to fix the heat conducting element 2 in the circumferential groove 11, as shown in the figure 4.

The locking ring 4 itself has an elastic or multi-segment structure, and can cooperate with the heat conduction element 2 to surround the circumferential groove 11 to ensure a tighter contact between the heat conduction element 2 and the conductive terminal 1 . The locking ring 4 and the heat conducting member 2 can be connected by one of adhesive connection, bayonet connection, plug connection, snap connection, screw connection, rivet connection and welding connection.

In the first feasible technical solution, the contact surface of the locking ring 4 and the heat conduction element 2 is an adhesive layer, and the adhesive layer is a viscous material made of a heat conduction material, and the locking ring 4 and the heat conduction element 2 are glued together through the adhesive layer. connected together.

In the second feasible technical solution, one of the joints between the locking ring 4 and the heat-conducting member 2 is a claw, and the other is a groove. Through the assembly of the claw and the groove, the locking ring 4 and the heat-conducting member 2 are in contact. The surfaces are connected together stably.

In the third feasible technical solution, one locking hook is provided at the joint of the locking ring 4 and the heat-conducting member 2, and the other is provided with a locking buckle. Through the assembly of the locking hook and the locking buckle, the contact surface of the locking ring 4 and the heat-conducting member 2 is Stable connection together.

In the fourth feasible technical solution, screw threads and screws are respectively provided at the joints of the locking ring 4 and the heat conducting element 2, and through the screw connection of the threads and screws, the contact surfaces of the locking ring 4 and the heat conducting element 2 are stably connected on the Together.

In the fifth feasible technical solution, connecting holes are respectively provided at the joints of the locking ring 4 and the heat conducting member 2, the rivets pass through the connecting holes, and one end of the rivets passing through the connecting holes is deformed to tighten the connecting holes, thereby Make the locking ring 4 and the contact surface of the heat conducting element 2 stably connected together.

In addition, one end of the locking ring 4 and the heat conducting member 2 can also be preset to be hinged, and the other end can be detachably connected, so as to be conveniently placed in the circumferential groove 11 .

In some embodiments, the conductive terminal 1 includes a connecting portion, and the circumferential groove 11 is disposed on the connecting portion. The circumferential groove 11 can be arranged at various positions of the terminal, and it is more convenient to make a groove on the connecting part, and it is not easy to damage the plug-in structure of the terminal.

In some embodiments, the contact surface between the heat conduction element 2 and the groove is provided with heat conduction silica gel. Thermally conductive silica gel can assist the connection between the conductive terminal 1 and the thermally conductive member 2, increase the effective contact area, increase the adhesion, and avoid the reduction of the effective contact area caused by vibration or the reduction of heat conduction efficiency due to the generation of air gaps; It can be used as a buffer between the heat conduction element 2 and the conductive terminal 1.

In some embodiments, the temperature sensor 3 is an NTC temperature sensor, a PTC temperature sensor or a bimetallic temperature sensor. The advantage of choosing NTC temperature sensor and PTC temperature sensor is that it is small in size and can measure gaps that cannot be measured by other thermometers; it is easy to use, and the resistance value can be arbitrarily selected from 0.1 to 100kΩ; it is easy to process into complex shapes, can be mass-produced, and has high stability. Good, strong overload capacity, suitable for conversion joints, which require small size and stable performance. Among them, the PTC sensor is more stable than the NTC sensor. The bimetal temperature sensor is composed of two metals with different expansion coefficients. When the temperature changes, the metal with a large expansion coefficient will bend, which has better vibration resistance and is suitable for electric vehicles.

In some embodiments, the material of the heat conduction element 2 includes heat conduction ceramics. In actual working conditions, it is necessary to consider not only the transfer efficiency of heat energy in the heat-conducting element 2, but also the protection of the sensor unit. The heat-conducting ceramic has excellent insulation resistance and good thermal conductivity, so it is used in conjunction with the temperature sensor 3.

In some embodiments, the thermal resistance value of the heat conducting element 2 is less than 12K·cm2/W. The thermal impedance value is the ratio between the temperature difference per unit area at both ends of the object and the power of the heat source when heat is transmitted on the object. It can be understood as the resistance encountered by heat on the heat flow path, reflecting the heat transfer capacity of the heat transfer medium, and indicating the temperature rise caused by 1W of heat. A simple analogy can be used to explain the meaning of thermal impedance. The heat transfer is equivalent to current, the temperature difference is equivalent to voltage, and thermal impedance is equivalent to resistance.

The smaller the thermal resistance value of the heat conduction element 2, the better the heat conduction capacity of the heat conduction element 2, which can transfer heat well, reduce the temperature difference between the two ends of the heat conduction medium, and thus improve the detection accuracy of the temperature sensor 3.

After repeated experiments by the inventor, it is known that when the thermal resistance value of the heat conduction element 2 is greater than 12K cm2/W, 1W of heat will generate a temperature difference of 12°C at a position of 1 square centimeter, and the greater the temperature difference, the greater the temperature error will be. The larger the temperature is, for the temperature control system, it is difficult to judge the actual temperature of the conductive terminal 1, so that effective temperature control measures cannot be carried out, which may cause the temperature control of the conductive terminal 1 to fail, causing the temperature of the conductive terminal 1 to be too high and cause damage There are even accidents. Therefore, the inventors set the thermal resistance value of the heat conducting element 2 to be less than 12K·cm2/W.

In order to verify the influence of the thermal resistance value of the heat conduction element 2 on the temperature drift of the heat conduction element 2, the inventor selected the same size and different thermal impedance value materials to make the heat conduction element 2, set the conductive terminal 1 to the same temperature, and then used the temperature sensor 3 Measure the temperature drift at the other end of the heat conducting element 2 and record it in Table 2.

The temperature drift value of the heat conduction element 2 refers to the temperature difference between the conductive terminal 1 and the other end of the heat conduction element 2 . If the temperature drift value is greater than 10K, it is unqualified.

Table 2: The influence of the thermal resistance value of different heat-conducting parts on the temperature drift of the heat-conducting parts

It can be seen from Table 2 that when the thermal resistance value of the heat conduction element 2 is less than 12K·cm2/W, the temperature drift value is less than 10K, and the temperature sensor 3 measures the temperature of the heat conduction element 2 more accurately. When the thermal impedance value of the heat conduction medium is greater than or equal to 12K cm2/W, the temperature drift value exceeds 10K. At this time, the temperature sensor 3 has a large error in measuring the temperature of the heat conduction medium, which will cause the feedback distortion of the measurement system, resulting in the inability to accurately control the conduction. The temperature condition of Terminal 1.

In some embodiments, the heat conduction time of the heat conduction element 2 is less than 20ms. Heat conduction time refers to the time it takes for heat to transfer from one end of the heat conduction element 2 to the other end. The smaller the heat conduction time, the faster the heat transfer speed of the heat conduction element 2, and the temperature of the conductive terminal 1 can be quickly fed back to the temperature sensor 3 On, so that the temperature control can achieve a smaller reaction time.

After repeated experiments by the inventor, it is known that when the heat conduction time of the heat conduction element 2 is greater than 20ms, when the temperature sensor 3 obtains the temperature of the heat conduction element 2, the temperature of the conductive terminal 1 has actually reached or exceeded the actual temperature value to be controlled. The temperature sensor 3 transmits the signal to the temperature control system, and the temperature control system issues an instruction after making a judgment. It also takes time to adjust the temperature control device to change the temperature. When the temperature adjustment measures of the temperature control device reach the conductive terminal 1, the real-time The temperature is no longer the temperature obtained by the temperature sensor 3, and this state will continue to circulate, and will never reach a stable thermal balance, and it will not be possible to achieve a state of real-time control of the conductive terminal 1 to maintain a stable temperature. Therefore, the inventor selected the heat conduction time of the heat conduction medium to be less than 20ms.

Although some specific embodiments of the present invention have been described in detail through examples, those skilled in the art should understand that the above examples are for illustration only, rather than limiting the scope of the present invention. Those skilled in the art will appreciate that modifications can be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

A terminal temperature measurement structure, characterized in that it includes: a conductive terminal, a heat conducting member and a temperature sensor;

Grooves are arranged on the conductive terminals;

The heat conducting element is at least partially disposed in the groove;

The temperature sensor is thermally connected with the heat conducting element.
A terminal temperature measuring structure according to claim 1, wherein the conductive terminal is cylindrical, the groove is a circumferential groove provided on the conductive terminal, and the heat conducting member has a The mating contact surface of the circumferential groove.
The terminal temperature measuring structure according to claim 2, wherein the contact surface is an arc surface.
The terminal temperature measuring structure according to claim 3, characterized in that, the degree of arc of the arc surface is 36°-180°.
A terminal temperature measuring structure according to claim 2, characterized in that a locking ring is also arranged in the circumferential groove, and the locking ring cooperates with the heat conducting element to fix the heat conducting element on the in the circumferential groove.
The terminal temperature measuring structure according to claim 2, wherein the conductive terminal includes a connecting portion, and the circumferential groove is arranged on the connecting portion.
The terminal temperature measuring structure according to claim 1, characterized in that, the contact surface between the heat conduction member and the groove is provided with heat conduction silica gel.
The terminal temperature measuring structure according to claim 1, wherein the temperature sensor is an NTC temperature sensor, a PTC temperature sensor or a bimetal temperature sensor.
The terminal temperature measuring structure according to claim 1, wherein the material of the heat-conducting member includes heat-conducting ceramics.
The terminal temperature measuring structure according to claim 1, wherein the thermal resistance value of the heat conducting member is less than 12K·cm2/W.
The terminal temperature measuring structure according to claim 1, characterized in that the heat conduction time of the heat conducting member is less than 20ms.