CN220625546U

CN220625546U - NTC temperature sensor

Info

Publication number: CN220625546U
Application number: CN202322318304.XU
Authority: CN
Inventors: 曾招停
Original assignee: Wuhan Topson Sensor Technology Co ltd
Current assignee: Wuhan Topson Sensor Technology Co ltd
Priority date: 2023-08-25
Filing date: 2023-08-25
Publication date: 2024-03-19
Anticipated expiration: 2033-08-25

Abstract

The present utility model relates to an NTC temperature sensor comprising: the upper surface and the lower surface of the PCB are provided with first metal contacts; the sensing element is provided with two leads extending outwards, the two leads respectively extend along the upper surface and the lower surface of the PCB in a fitting way, and the two leads are respectively welded with the first metal contacts on the upper surface and the lower surface; wherein the welding part of the sensing element, the two leads and the two first metal contacts is plastic-wrapped with an insulating sleeve. According to the utility model, the head encapsulation design of the sensing element is canceled, the head of the sensing element is not used, and the pre-cladding is not performed by using a sleeve or a bracket to realize insulation, but a PCB (printed circuit board) is adopted to insulate and insulate two leads, the PCB is used for fixing the leads of the sensing element, and the sensing element is fixed by the PCB, so that the sensing element is not easy to deviate, and the performance and the stability of a product are improved; the batch production can be semi-automatically carried out, and the production efficiency is improved.

Description

NTC temperature sensor

Technical Field

The utility model relates to the technical field of sensors, in particular to an NTC temperature sensor.

Background

At present, 3 main current methods exist, namely, the 1 st method is that NTC is directly welded with wires, then encapsulated after welding, and then inserted into a bullet shell for encapsulation; the 2 nd method is that the front end of the electric wire is firstly separated into wires and penetrates through the shrink sleeve and then is welded with the NTC, then two shrink sleeves are used for pin insulation, and finally the wires are inserted into a bullet head shell and then encapsulated; the 3 rd approach is NTC direct wire-bonding, then fitting into a custom sensor holder, filling the sensor holder with epoxy, and finally inserting into a bullet-shaped housing for potting.

All three methods require additional insulation treatment on the pins (leads) of the NTC, and the processing cost and efficiency are reduced.

Disclosure of Invention

The embodiment of the utility model provides an NTC temperature sensor to at least solve one of the above technical problems.

An NTC temperature sensor comprising: the upper surface and the lower surface of the PC B plate are respectively provided with a first metal contact; the sensing element is provided with two leads extending outwards, the two leads respectively extend along the upper surface and the lower surface of the PC B plate in a fitting way, and the two leads are respectively welded with the first metal contacts of the upper surface and the lower surface; wherein the welding part of the sensing element, the two leads and the two first metal contacts is plastic-wrapped by an insulating sleeve.

According to the NTC temperature sensor, the head encapsulation design of the sensing element is canceled, the head of the sensing element is not used, and the sleeve or the bracket is not used for pre-cladding to realize insulation, but a PCB (printed circuit board) is used for insulating and insulating two leads, a PC B board is used for fixing the leads of the sensing element, and the sensing element is fixed by the PC B, so that the sensing element is not easy to deviate, and the performance and the stability of a product are improved; the batch production can be semi-automatically carried out, and the production efficiency is improved.

In one embodiment, the sensing element comprises a thermosensitive chip and a wrapping layer wrapping the thermosensitive chip, and one ends of the two leads and the thermosensitive chip extend out of the wrapping layer.

In one embodiment, the PCB board includes a main board and an extension board, the extension board is connected to the main board, the first metal contact is disposed on the main board, and a portion of the lead is attached to the extension board and extends along a direction of the extension board.

In one embodiment, a positioning hole is formed in the opposite corner of the main board.

In one embodiment, the PCB further comprises two connecting wires, and the connecting wires are connected with the PCB.

In one embodiment, the upper surface and the lower surface of the PCB board are respectively provided with a second metal contact, and the two connecting wires are respectively welded with the second metal contacts on the upper surface and the lower surface.

In one embodiment, the connection wire comprises a connection lug provided at the end, which connection lug is soldered to the second metal contact.

In one embodiment, the insulating sleeve surrounds the connection of the connection wire to the second metal contact and a portion of the connection wire adjacent to the second metal contact.

In one embodiment, the insulating sleeve is bullet-shaped.

In one embodiment, the insulating sleeve is made of an epoxy material.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of the overall structure of an embodiment of the present utility model;

FIG. 2 is a cross-sectional view A-A of FIG. 1;

FIG. 3 is an enlarged view at B of FIG. 2;

fig. 4 is a prior art schematic.

Reference numerals:

PC B board 100, bubble space 101, first metal contact 110, main board 120, positioning hole 121, extension board 130, second metal contact 140;

sensing element 200, lead 210, thermal chip 220, and wrapping layer 230;

an insulating sleeve 300;

a connection wire 400 and a connection wire head 410.

Detailed Description

In order that the utility model may be readily understood, a more complete description of the utility model will be rendered by reference to the appended drawings. Preferred embodiments of the present utility model are shown in the drawings. This utility model may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

In the prior art, three methods are generally used to plastic package the NTC sensing element.

The 1 st method mainly comprises the steps that in the process of inserting the encapsulated semi-finished product into the bullet shell, centering of the semi-finished product is difficult to ensure, under the condition that the semi-finished product is not centered, too little encapsulation occurs in the process of encapsulating, and under the condition that the semi-finished product is not centered, the risk of insulation and voltage resistance failing is increased; too much encapsulation can occur during encapsulation, which can result in the NTC head not bottoming out and a slow reaction time.

The 2 nd method is mainly that the semi-finished product is in the process of inserting bullet head shell embedment, because the sleeve OD is too big, can't form close fit with the chip pin, there is the space in the centre, can produce capillary phenomenon in the embedment process, can produce bubble space 101 (like fig. 4) in the sleeve pipe through capillary phenomenon, causes steam to invade through the gap easily and remain in long-term use, forms the water droplet, corrodes the resistance lead wire or flow into NTC inside through the gap and cause the resistance drift, makes product life-span reduce.

The 3 rd way is mainly that the semi-finished product is in the process of filling the sensor bracket with epoxy resin, and because the sensor bracket is bonded with the NTC and the semi-finished product welded by the electric wire through the epoxy resin, the epoxy resin is in a liquid state before solidification, the sensor bracket and the semi-finished product can generate relative displacement in the solidification process, capillary phenomenon can be generated after solidification is finished, bubble space can be generated in the sensor bracket through the capillary phenomenon, water vapor is easy to cause to invade and remain through gaps in the long-term use process, water drops are formed, and resistance leads are corroded or flow into the NTC through the gaps to cause drift of resistance, so that the service life of the product is reduced.

Referring to fig. 1 to 3, an NTC temperature sensor according to an embodiment of the present utility model includes a PCB board 100, a sensing element 200, and an insulation sleeve 300.

The upper and lower surfaces of the PC B board 100 are provided with first metal contacts 110; the sensor element 200 has two leads 210 extending outwards, and the two leads 210 respectively extend along the upper and lower surfaces of the PC B board 100 in a fitting manner, so that insulation treatment of the two leads 210 is achieved, and no encapsulation of the two leads or insulation fixation of the leads by using a sleeve or a bracket is required. Two leads 210 are respectively welded to the first metal contacts 110 on the upper and lower surfaces; wherein the sensor element 200, the two leads 210 and the soldered connection of the two first metal contacts 110 are plastic-encased with an insulating sleeve 300.

According to the NTC temperature sensor, the head encapsulation design of the sensing element is canceled, the head of the sensing element is not used, the sleeve or the bracket is not used for pre-cladding to realize insulation, the PCB is used for insulating and insulating the two leads, the PC B plate is used for fixing the leads of the sensing element, the sensing element is fixed by the PC B, and the sensing element is not easy to deviate, so that the performance and the stability of a product are improved. The two leads 210 are respectively attached and extended along the upper and lower surfaces of the PC B board 100 to stabilize the extending path of the leads, the sensor element 200 is fixed by the PC B to form a semi-finished product, and the semi-finished product is stably connected, so that the semi-finished product is placed in the middle and then wrapped by an insulating sleeve, and is not easy to deviate, in this case, the reaction speed of the NTC can be improved, the occurrence of poor insulation and voltage resistance can be reduced, and the performance and stability of the product can be improved; the batch production can be semi-automatically carried out, and the production efficiency is improved; compared with the pain point which is shown in fig. 4 and is easy to generate the bubble space 101 in the prior art, the design scheme is provided for solving the problems that the reaction time is not fast enough, the insulation withstand voltage reject ratio is high, the bubble is easy to generate in the traditional bullet type temperature sensor, and the insulation withstand voltage is better, the reaction is faster and the bubble is not generated; under the condition of ensuring the yield and improving the reaction speed, the method is more reliable.

Referring to fig. 1 to 3, in some embodiments of the present utility model, the sensing element 200 includes a thermo-sensitive chip 220 and a wrapping layer 230 wrapping the thermo-sensitive chip 220, and two ends of the leads 210 are connected to the thermo-sensitive chip 220 and extend out of the wrapping layer 230. The thermal chip 220 may be an NTC resistor, the wrapping layer 230 may be made of glass, so as to protect the thermal chip 220, and in addition, the ends of the thermal chip 220 and the lead 210 are usually welded, and the wrapping layer 230 also plays a role in wrapping and protecting the welded part of the thermal chip 220 and the lead 210, so that the end of the lead 210 is prevented from being easily unwelded.

In a further embodiment of the present utility model, the PCB board 100 includes a main board 120 and an extension board 130, the extension board 130 is connected to the main board 120, and the extension board 130 and the main board 120 are generally integrally formed. The first metal contacts 110 are disposed on the motherboard 120, and a portion of the leads 210 are attached to the extension board 130 and extend along the direction of the extension board 130, and the extension board 130 is used for attaching the leads 210, so as to stabilize the leads 210.

In a further embodiment of the present utility model, a positioning hole 121 is formed at a diagonal position of the motherboard 120, so that when the lead 210 is soldered with the first metal contact 110, the motherboard 120 can be positioned by inserting a positioning post into the positioning hole 121, and precise soldering is facilitated.

Referring to fig. 2, in some embodiments of the present utility model, two connection lines 400 are further included, and the connection lines 400 are connected to the PC B board 100, so that information obtained by the sensing element 200 is transmitted to the outside and external power is obtained.

In a further embodiment of the present utility model, the upper and lower surfaces of the PCB 100 are respectively provided with the second metal contacts 140, and the two connecting wires 400 are respectively welded with the second metal contacts 140 on the upper and lower surfaces, so as to realize the connection between the PCB 100 and the connecting wires 400.

In order to make the connection between the PCB 100 and the connection wire 400 more stable and firm, and not easy to fail, in a further embodiment of the present utility model, the insulation sleeve 300 wraps the connection between the connection wire 400 and the second metal contact 140 and the portion of the connection wire 400 adjacent to the second metal contact 140, so as to wrap and protect the soldered connection, avoid oxidation and easily remove solder.

Referring to fig. 2, in a further embodiment of the present utility model, the connection wire 400 includes a connection wire head 410 provided at an end portion, and the connection wire head 410 is soldered to the second metal contact 140, thereby facilitating connection of the connection wire 400 to the second metal contact 140.

In production, the semi-finished product formed by welding the PCB board 100 and the sensing element 200 is centered in the bullet-shaped casing to encapsulate the insulating material to form the insulating sleeve 300, so in some embodiments, the insulating sleeve 300 is bullet-shaped, and plays a role in comprehensively protecting the PCB board 100 and the sensing element 200.

Specifically, the insulating sleeve 300 is made of an epoxy resin material, so that the material has good stability, is not easy to oxidize and corrode, and has a good insulating effect.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims

1. An NTC temperature sensor comprising:

the PCB (100) is provided with first metal contacts (110) on the upper surface and the lower surface;

the sensing element (200) is provided with two leads (210) which extend outwards, the two leads (210) respectively extend along the upper surface and the lower surface of the PCB (100) in a fitting way, and the two leads (210) are respectively welded with the first metal contacts (110) on the upper surface and the lower surface;

wherein the welding parts of the sensing element (200), the two leads (210) and the two first metal contacts (110) are plastic-wrapped by an insulating sleeve (300).

2. The NTC temperature sensor according to claim 1, characterized in that the sensing element (200) comprises a thermo-sensitive chip (220) and a wrapping layer (230) wrapping the thermo-sensitive chip (220), and that two leads (210) are provided at one end and the thermo-sensitive chip (220) and extend out of the wrapping layer (230).

3. The NTC temperature sensor of claim 2 characterized in that the PCB board (100) comprises a main board (120) and an extension board (130), the extension board (130) is connected to the main board (120), the first metal contact (110) is disposed on the main board (120), and a portion of the lead (210) is attached to the extension board (130) and extends along the direction of the extension board (130).

4. The NTC temperature sensor according to claim 3, characterized in that a positioning hole (121) is provided at a diagonal of the main plate (120).

5. The NTC temperature sensor according to claim 1, characterized in that it further comprises two connection wires (400), said connection wires (400) being connected to the PCB board (100).

6. The NTC temperature sensor of claim 5, characterized in that the upper and lower surfaces of the PCB (100) are provided with second metal contacts (140), and the two connection wires (400) are welded to the second metal contacts (140) of the upper and lower surfaces, respectively.

7. The NTC temperature sensor according to claim 6, characterized in that the connection wire (400) comprises a connection lug (410) provided at the end, the connection lug (410) being soldered with the second metal contact (140).

8. The NTC temperature sensor according to claim 6, characterized in that the insulating sleeve (300) encloses the connection of the connection wire (400) with the second metal contact (140) and the part of the connection wire (400) adjacent to the second metal contact (140).

9. The NTC temperature sensor according to claim 1, characterized in that the insulating sleeve (300) is bullet-shaped.

10. The NTC temperature sensor according to claim 1, characterized in that the insulating sleeve (300) is made of an epoxy material.