Charging plug

Abstract

Provided is a charging plug in which it is not necessary to open a hole and onto which a temperature sensor has been attached in a high heat-joining state.　This charging plug is provided with: a pin-like plug body (2); a temperature sensor (3); and a metal clip member (4) having been attached to the plug body in a state in which the temperature sensor is in contact with the plug body. The plug body is provided with a pin section (2a) that is inserted into a counterpart connector and plug-in connected thereto, and a plug basal-end section (2b) provided on the basal end-side of the pin section. The clip member, with the temperature sensor being in contact with the plug basal-end section, clasps the temperature sensor between the clip member itself and the plug basal-end section, and is anchored to the plug basal-end section.

Description

Charging plug

[0001] The present invention relates to a charging plug with a temperature sensor for charging a battery mounted on an EV or the like.

[0002] To charge the battery installed in an EV or other vehicle, it is necessary to connect the charging connector to the on-board connector (inlet) and then mate the charging socket and charging plug (charging pins) on both sides. The source of heat in the charging plug during charging is Joule heat, which is generated when charging current flows through the contact resistance between the charging plug and socket contacts. Temperature monitoring of this part is used to control the charging current and to cut off the current when it reaches an abnormal temperature.

[0003] As examples of prior art for such temperature monitoring, for example, Patent Document 1 describes a charging inlet assembly having a terminal with a temperature sensor built into a replaceable pin, and Patent Document 2 describes a charging plug having a temperature sensor unit built into a sensor recess in a power contact pin.

[0004] US Patent Application Publication No. 2021 / 0078419 German Patent Application Publication No. 102018130835

[0005] The above-described conventional technology still has the following problems. Specifically, in the above-described conventional charging plug, a temperature sensor is inserted into a hole (or recess) drilled in the charging plug. However, this requires drilling a hole in the charging plug, and also requires drilling a wiring hole or the like to connect the temperature sensor to the internal wiring, resulting in the inconvenience of complex processing work and high manufacturing costs. Furthermore, there is a problem that a cavity is formed in the charging plug, blocking the current flow path. While it is possible to simply attach a temperature sensor to the outside of the charging plug with adhesive, there are problems such as insufficient thermal bonding due to the adhesive and the risk of the temperature sensor becoming detached due to impact, etc.

[0006] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a charging plug in which a temperature sensor is attached in a highly thermally coupled state without the need for drilling holes in the charging plug.

[0007] The present invention employs the following configuration to solve the above problems: That is, a charging plug according to a first aspect of the present invention includes a pin-shaped plug body, a temperature sensor, and a metal clip member attached to the plug body with the temperature sensor in contact with the plug body, the plug body includes a pin portion that is inserted into a mating connector for plug-in connection, and a plug base end portion provided on the base end side of the pin portion, and the clip member is fixed to the plug base end with the temperature sensor sandwiched between the clip member and the plug base end with the temperature sensor in contact with the plug base end.

[0008] In this charging plug, the clip member is fixed to the base end of the plug with the temperature sensor sandwiched between the clip member and the base end of the plug while the temperature sensor is in contact with the base end of the plug. This allows the temperature sensor to be attached without drilling a hole in the plug body, and the temperature of the plug body can be transmitted to the temperature sensor even via the metal clip member, achieving high thermal coupling and enabling highly accurate temperature measurement. Furthermore, the temperature sensor is easily attached and detached, and can be easily attached even after the plug body and power line have been connected by crimping or welding.

[0009] A charging plug according to a second aspect of the present invention is the charging plug of the first aspect, wherein the temperature sensor has a flat contact surface that contacts the plug base end, and the plug base end has a flat installation surface on which the temperature sensor is installed. That is, in this charging plug, the plug base end has a flat installation surface on which the temperature sensor is installed, and the plug base end and the temperature sensor contact each other at their flat surfaces, thereby achieving high thermal conductivity and enabling more accurate measurements.

[0010] A charging plug according to a third aspect of the present invention is the charging plug according to the first or second aspect of the present invention, wherein the clip member includes a spring portion that presses the temperature sensor toward the base end of the plug. That is, in this charging plug, the clip member includes a spring portion that presses the temperature sensor toward the base end of the plug, thereby maintaining stable contact between the plug body and the temperature sensor and ensuring reliable thermal coupling.

[0011] A charging plug according to a fourth invention is the charging plug according to any one of the first to third inventions, characterized in that the temperature sensor includes a retaining protrusion that engages with the clip member when attached to the base end of the plug. That is, in this charging plug, the temperature sensor includes a retaining protrusion that engages with the clip member when attached to the base end of the plug, so that the temperature sensor can be positioned and attached, and it is possible to prevent the temperature sensor from shifting position or coming off the clip member due to vibration, etc.

[0012] A charging plug according to a fifth invention is the charging plug according to any one of the first to fourth inventions, wherein the clip member is formed with a U-shaped cross section that can be attached by sandwiching the plug base end with the temperature sensor disposed between the clip member and the plug base end. That is, in this charging plug, the clip member is formed with a U-shaped cross section that can be attached by sandwiching the plug base end with the temperature sensor disposed between the clip member and the plug base end, so that the clip member and the plug base end can be easily fitted together with the temperature sensor sandwiched between them.

[0013] A charging plug according to a sixth aspect of the present invention is the charging plug according to any one of the first to fifth aspects, wherein the clip member includes an annular portion through which the pin can be inserted, and a pair of leaf spring portions that extend from the annular portion toward the plug base end and sandwich the plug base end when the pin is inserted into the annular portion. That is, in this charging plug, the clip member includes an annular portion through which the pin can be inserted, and a pair of leaf spring portions that extend from the annular portion toward the plug base end and sandwich the plug base end when the pin is inserted into the annular portions. Therefore, with the pin inserted into the annular portions, the clip member will not come off when plugged in.

[0014] A charging plug according to a seventh aspect of the present invention is the charging plug according to any one of the first to sixth aspects, characterized in that the temperature sensor includes an insulating film and a heat-sensitive element provided on the insulating film. That is, in this charging plug, the temperature sensor includes an insulating film and a heat-sensitive element provided on the insulating film, so that the thin insulating film can provide high insulation and low thermal resistance, and the charging plug can be made thinner.

[0015] The charging plug according to an eighth aspect of the present invention is the charging plug according to any one of the first to seventh aspects, wherein the temperature sensor is a rectangular parallelepiped having a contact surface with the plug base end, and the clip member has sensor contact portions that contact at least four outer peripheral surfaces of the temperature sensor other than the contact surface. That is, in this charging plug, the clip member has sensor contact portions that contact at least four outer peripheral surfaces of the temperature sensor other than the contact surface, which provides high thermal conductivity to the temperature sensor and a high retention effect for the temperature sensor.

[0016] The present invention provides the following advantages. Specifically, with the charging plug according to the present invention, the clip member is fixed to the base end of the plug with the temperature sensor sandwiched between the clip member and the base end of the plug while the temperature sensor is in contact with the base end of the plug. This allows the temperature sensor to be attached without drilling a hole in the plug body, and the temperature of the plug body can be transmitted to the temperature sensor even via the metal clip member, resulting in high thermal coupling and enabling highly accurate temperature measurement. Therefore, the charging plug according to the present invention does not require drilling or other processes and enables highly accurate temperature measurement, making it possible to control the charging current and shut off the current when an abnormal temperature is reached with high accuracy.

[0017] 1 is a perspective view showing a first embodiment of a charging plug according to the present invention. FIG. 2 is a perspective view showing a plug body in the first embodiment. FIG. 3 is a perspective view showing a clip member in the first embodiment. FIG. 4 is a perspective view showing a temperature sensor in the first embodiment. FIG. 5 is a perspective view showing a second embodiment of a charging plug according to the present invention. FIG. 6 is a perspective view showing a plug body in the second embodiment. FIG. 7 is a perspective view showing a temperature sensor in the second embodiment. FIG. 8 is a perspective view showing a clip member in the second embodiment. FIG. 9 is a perspective view showing another example of the first embodiment of a charging plug according to the present invention. FIG. 10 is a perspective view showing a temperature sensor in the other example of the first embodiment.

[0018] A first embodiment of a charging plug according to the present invention will be described below with reference to Figures 1 to 4. Note that in some of the drawings used in the following description, the scale has been appropriately changed as necessary to make each part recognizable or easily recognizable.

[0019] 1 to 4 , the charging plug 1 of this embodiment includes a pin-shaped plug body 2, a temperature sensor 3, and a metal clip member 4 attached to the plug body 2 with the temperature sensor 3 in contact with the plug body 2. The plug body 2 includes a pin portion 2a that is inserted into a mating connector (not shown) for plug-in connection, and a plug base end portion 2b provided on the base end side of the pin portion 2a. The clip member 4 is fixed to the plug base end portion 2b with the temperature sensor 3 sandwiched between the clip member 4 and the plug base end portion 2b with the temperature sensor 3 in contact with the plug base end portion 2b.

[0020] The temperature sensor 3 has a flat contact surface 3a on its back surface that contacts the plug base end 2b. The temperature sensor 3 also has a retaining protrusion 3b that engages with the clip member 4 when attached to the plug base end 2b. The plug base end 2b also has a flat installation surface 2c on its upper surface on which the temperature sensor 3 is installed. That is, the temperature sensor 3 is placed with the flat contact surface 3a on its back surface in contact with the flat installation surface 2c on the upper surface of the plug base end 2b. The pin portion 2a is cylindrical with a tapered tip, and the plug base end 2b has an octagonal cross section. The entire plug body 2, including the installation surface 2c, is processed by cold forging technology, providing excellent thermal coupling.

[0021] The clip member 4 includes a spring portion 4a that presses the temperature sensor 3 toward the plug base end 2b. Furthermore, the clip member 4 is formed with a U-shaped cross section so that it can be attached by sandwiching the plug base end 2b with the temperature sensor 3 disposed between the clip member 4 and the plug base end 2b. That is, the clip member 4 includes a connecting portion 4d that connects the pair of leaf spring portions 4c, and a pair of leaf spring portions 4c on both sides of the connecting portion 4d. By fitting the plug base end 2b into the pair of leaf spring portions 4c, the pair of leaf spring portions 4c clamp both side surfaces of the plug base end 2b.

[0022] The clip member 4 is formed by processing a Cu plate or the like, and has springiness (elasticity) corresponding to the shape of the plug base end 2 b so that the pair of leaf spring portions 4 c can fit into and clamp the plug base end 2 b. If necessary, the clip member 4 may be firmly fixed by welding to the plug base end 2 b.

[0023] The spring portion 4a is formed in a plate shape and protrudes from the connecting portion 4d toward the pin portion 2a. The spring portion 4a is disposed on the temperature sensor 3, and is formed so that its tip end is inclined downward from its base end connected to the connecting portion 4d toward the temperature sensor 3, and the tip end biases and presses the temperature sensor 3 downward toward the plug base end 2b.

[0024] The temperature sensor 3 includes an insulating film 3c, a heat-sensitive element 3d provided on the insulating film 3c, a resin sealing portion 3e sealing the heat-sensitive element 3d on the insulating film 3c, and a metal support housing 5 covering the bottom surface and three wall surfaces of the resin sealing portion 3e. The heat-sensitive element 2 is, for example, a chip thermistor or a thin-film thermistor, and is connected to pattern wiring (not shown) formed on the insulating film 3c.

[0025] The insulating film 3c is formed of, for example, a strip-shaped polyimide film, and has a thermal element 3d at its tip. This tip is disposed within the supporting housing 5, and the base end extends outward from the supporting housing 5. The resin sealing portion 3e is, for example, epoxy resin filled inside the supporting housing 5. The supporting housing 5 has a bottom surface portion 5a, a tip wall portion 5b, and left and right side wall portions 5c, and is formed by sheet metal processing of a Cu plate or the like. The back surface of the supporting housing 5 serves as the contact surface 3a.

[0026] A pair of retaining projections 3b are formed on the left and right sidewalls 5c and protrude upward. When the temperature sensor 3 is sandwiched between the clip member 4 and the plug base end 2b, the pair of retaining projections 3b engage with the tips of the spring portions 4a. A step portion 2d is formed on the tip side of the installation surface 2c of the plug base end 2b, and the tip of the support housing 5 of the temperature sensor 3 placed on the installation surface 2c abuts against the step portion 2d. Therefore, the temperature sensor 3 is positioned by the retaining projections 3b engaging with the spring portions 4a and the tip of the temperature sensor 3 engaging with the step portion 2d.

[0027] As described above, in the charging plug 1 of this embodiment, the clip member 4 is fixed to the plug base end 2b with the temperature sensor 3 sandwiched between it and the plug base end 2b while the temperature sensor 3 is in contact with the plug base end 2b. This allows the temperature sensor 3 to be attached without drilling a hole in the plug body 2, and the temperature of the plug body 2 can be transmitted to the temperature sensor 3 even via the metal clip member 4, resulting in high thermal coupling and enabling highly accurate temperature measurement.

[0028] Furthermore, the temperature sensor 3 is easily detachable, and can be easily attached even after the plug body 2 and the power line are connected by crimping or welding. In particular, the clip member 4 has a U-shaped cross section that allows it to be attached by sandwiching the plug base end 2b with the temperature sensor 3 disposed between it and the plug base end 2b. Therefore, the clip member 4 and the plug base end 2b can be easily fitted together with the temperature sensor 3 sandwiched between them. Furthermore, even if the clip member 4 is fixed to the plug base end 2b by welding, the structure allows for easy removal by pulling out the temperature sensor 3 while lifting the tip of the spring portion 4a with a jig or the like.

[0029] Furthermore, since the plug base end 2b has a flat installation surface 2c on which the temperature sensor 3 is installed, the plug base end 2b and the temperature sensor 3 come into contact with each other on their flat surfaces, thereby achieving high thermal conductivity and enabling more accurate measurements. Furthermore, since the clip member 4 has a spring portion 4a that presses the temperature sensor 3 toward the plug base end 2b, a stable contact state between the plug body 2 and the temperature sensor 3 can be maintained, ensuring reliable thermal coupling.

[0030] Furthermore, the temperature sensor 3 is provided with a retaining protrusion 3b that engages with the clip member 4 when attached to the plug base end 2b, allowing the temperature sensor 3 to be positioned and attached, and preventing it from shifting position due to vibration or coming off the clip member 4. Furthermore, the temperature sensor 3 is provided with an insulating film 3c and a heat-sensitive element 3d provided on the insulating film 3c, so that the thin insulating film 3c provides high insulation and low thermal resistance, and also allows for a thinner design.

[0031] Next, a second embodiment of the charging plug according to the present invention will be described below with reference to Figures 5 to 8. In the description of the following embodiment, the same components as those described in the above embodiment will be denoted by the same reference numerals, and the description thereof will be omitted.

[0032] The difference between the second embodiment and the first embodiment is that, in the first embodiment, the clip member 4 has only a pair of leaf spring portions 4c for attachment to the plug body 2, whereas in the charging plug 21 of the second embodiment, as shown in Figures 5 to 8, the clip member 24 has a ring portion 24a through which the pin portion 2a can be inserted, and a pair of leaf spring portions 24b that extend from the ring portion 24a toward the plug base end 22b and sandwich the plug base end 22b when the pin portion 2a is inserted into the ring portion 24a.

[0033] For this reason, in the second embodiment, the pin portion 2a is inserted through the annular portion 24a until the annular portion 24a abuts against the plug base end 22b, and the pair of leaf spring portions 24b are positioned along both sides of the plug base end 2b to sandwich the plug base end 22b, thereby attaching the clip portion 24 to the plug body 22. That is, in the first embodiment, the pair of leaf spring portions 24b sandwich the plug base end 22b from above, but in the second embodiment, the pair of leaf spring portions 24b sandwich the plug base end 22b from the front on the pin portion 2a side.

[0034] The second embodiment also differs from the first embodiment in that the temperature sensor 23 has a rectangular parallelepiped shape in a plan view, as shown in Fig. 7. Furthermore, in the temperature sensor 23 of the second embodiment, the thermal element (not shown) is connected to a pair of lead wires 23c rather than to an insulating film. The temperature sensor 23 includes a box-shaped support housing 25 having a bottom 25a and three wall portions 25c, and a resin sealing portion 3e that is filled in the support housing 25 and seals the thermal element.

[0035] That is, the temperature sensor 23 has a rectangular parallelepiped shape having a contact surface 3a (the back surface of the support housing 25) with the plug base end 22b, and the clip member 24 has a sensor contact portion 24c that contacts the four outer peripheral surfaces of the temperature sensor 23 other than the contact surface 3a. The sensor contact portion 24c is formed with a rectangular cross section so as to cover the four outer peripheral surfaces of the temperature sensor 23: the top surface, both side surfaces, and the tip surface. The clip member 24 also has a retaining portion 24d that abuts against the base end of the temperature sensor 23 in the attached state. The retaining portion 24d is located adjacent to the sensor contact portion 24c, protrudes from the annular portion 24a toward the plug base end 22b, and is set slightly lower than the sensor contact portion 24c. That is, before attaching the clip member 24 to the plug body 22, the temperature sensor 23 is inserted under the sensor contact portion 24c, and the tip surface of the temperature sensor 23 is brought into contact with the tip portion of the sensor contact portion 24c, whereby the base end of the temperature sensor 23 is locked by the retaining portion 24d. When the clip member 24 is attached to the plug body 22 in this state, the temperature sensor 23 is sandwiched between the clip member 24 and the plug base end 22b, and the tip surface of the temperature sensor 23 abuts against the tip portion of the sensor contact portion 24c, and the base end of the temperature sensor 23 is locked by the retaining portion 24d, thereby positioning the temperature sensor 23 and preventing it from coming off.

[0036] Note that the plug base end 22b of the second embodiment does not have a stepped portion 2d as in the first embodiment. In this way, in the charging plug 21 of the second embodiment, the clip member 24 includes an annular portion 24a through which the pin portion 2a can be inserted, and a pair of leaf spring portions 24b that extend from the annular portion 24a toward the plug base end 22b and sandwich the plug base end 22b when the pin portion 2a is inserted into the annular portion 24a. Therefore, since the pin portion 2a is inserted into the annular portion 24a, the clip member 24 will not come off when plugged in. Furthermore, the clip member 24 includes sensor contact portions 24c that contact at least four outer circumferential surfaces of the temperature sensor 23 other than the contact surface 3a. This provides high thermal conductivity to the temperature sensor 23 and provides a high retention effect for the temperature sensor 23.

[0037] The technical scope of the present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the spirit of the present invention.

[0038] For example, in the first embodiment, a heat-sensitive element 3d is provided on the insulating film 3c, and the insulating film 3c extends outward from the supporting housing 5. However, as another example of the first embodiment, as shown in Figures 9 and 10, the charging plug 1A may employ a temperature sensor 3A in which the heat-sensitive element 3d is connected to a pair of lead wires 23c, and the pair of lead wires 23c may extend outward from the supporting housing 5.

[0039] DESCRIPTION OF SYMBOLS 1, 1A, 21... Charging plug, 2, 22... Plug body, 2a... Pin portion, 2b, 22b... Plug base end portion, 2c... Installation surface, 3, 23... Temperature sensor, 3a... Contact surface, 3b... Anti-detachment protrusion, 3c... Insulating film, 3d... Heat-sensitive element, 4, 24... Clip member, 4a... Spring portion, 4c, 24b... Leaf spring portion, 24a... Ring portion, 24c... Sensor contact portion

Claims

1. A charging plug comprising: a pin-shaped plug body; a temperature sensor; and a metal clip member attached to the plug body with the temperature sensor in contact with the plug body; the plug body comprising a pin portion that is inserted into a mating connector for plug-in connection, and a plug base end portion provided on the base end side of the pin portion; and the clip member is fixed to the plug base end portion with the temperature sensor sandwiched between the clip member and the plug base end with the temperature sensor in contact with the plug base end.

2. A charging plug according to claim 1, wherein the temperature sensor has a flat contact surface that contacts the base end of the plug, and the base end of the plug has a flat installation surface on which the temperature sensor is installed.

3. A charging plug according to claim 1, wherein the clip member has a spring portion that presses the temperature sensor toward the base end of the plug.

4. A charging plug according to claim 1, wherein the temperature sensor is provided with a retaining projection that engages with the clip member when attached to the base end of the plug.

5. A charging plug according to claim 1, wherein the clip member is formed with a U-shaped cross section so that it can be attached by clamping the base end of the plug with the temperature sensor disposed between the clip member and the base end of the plug.

6. A charging plug as described in claim 1, wherein the clip member comprises a ring portion through which the pin portion can be inserted, and a pair of leaf spring portions that extend from the ring portion toward the base end of the plug and sandwich the base end of the plug when the pin portion is inserted into the ring portion.

7. A charging plug according to claim 1, wherein the temperature sensor comprises an insulating film and a heat-sensitive element provided on the insulating film.

8. A charging plug according to claim 1, wherein the temperature sensor is a rectangular parallelepiped having a contact surface with the base end of the plug, and the clip member is provided with sensor contact portions that contact at least four outer peripheral surfaces of the temperature sensor other than the contact surface.

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