thermistor temperature sensor

Abstract

The utility model relates to a kind of thermistor temperature sensors, comprising: sensor connection unit (2), the sensor connection unit (2) includes connecting terminal (21) and shell (22), for connecting temperature sensor to other components, protective shell (3), thermistor (5), the thermistor (5) is arranged in protective shell (3), pin (51), the pin (51) connects thermistor (5) and connecting terminal (21) in sensor connection unit (2), connecting terminal in the sensor connection unit (2) is provided with fixed value resistance (23), and thermistor (5) forms parallel relationship, so that thermistor is not influenced by overvoltage or overcurrent due to temperature mutation.

Description

Technical Field

[0001] This utility model relates to a thermistor temperature sensor, and more particularly to a thermistor temperature sensor with a fixed resistor. Background Technology

[0002] A thermistor temperature sensor is a temperature sensor that measures temperature based on the principle that its resistance value decreases rapidly as the temperature rises.

[0003] CN 110954237 A discloses an engine coolant temperature sensor. This engine coolant temperature sensor includes a first terminal, a second terminal, a thermistor, an electromagnet, and a reset switch. One end of the thermistor is electrically connected to the first terminal. The electromagnet has a first terminal and a second terminal. The first terminal is electrically connected to the second terminal, and the second terminal is electrically connected to the other end of the thermistor and one end of the reset switch. The other end of the reset switch is electrically connected to the first terminal. The thermistor operates normally when the current does not exceed a current threshold. When the current exceeds the current threshold, the electromagnet attracts the reset switch, causing the reset switch to close, short-circuiting the thermistor. When the current decreases back to below the current threshold, the reset switch opens again, allowing the thermistor to be reconnected. This prevents solder melting due to excessive current, avoiding sensor failure and ensuring normal vehicle operation.

[0004] CN107576412A discloses a temperature sensor with two thermistors. The probe, assembled on an engine, houses more than one thermistor. Even when one thermistor is not working, the other thermistor continues to sense the engine temperature, thereby extending the product's reliability and lifespan. The packaging structure includes a connector housing with a terminal electrically connected to the vehicle's electronic control unit; a probe covering the lower outer side of the connector housing and having a mounting portion for insertion into the vehicle engine; and a sensing unit located inside the probe, including a first thermistor and a second thermistor, both electrically connected to wires extending from the terminal of the connector housing.

[0005] In existing thermistor temperature sensors, complex structures and additional thermistors are used to address the problem of overcurrent or overvoltage damage, resulting in higher component costs and larger size, which affects product dimensions and price. Therefore, ordinary thermistor temperature sensors cannot effectively solve the problem of thermistor damage under overcurrent or overvoltage conditions. Utility Model Content

[0006] Therefore, the technical problem to be solved by this utility model is: a thermistor temperature sensor with high reliability that is not affected by overcurrent or overvoltage.

[0007] This utility model proposes a thermistor temperature sensor, comprising:

[0008] A sensor connection unit, comprising connection terminals and a housing, is used to connect a temperature sensor to other components.

[0009] Protective case

[0010] The thermistor is housed within a protective casing.

[0011] This pin connects the thermistor and the connection terminal within the sensor connection unit.

[0012] A fixed resistor is provided on the connection terminal in the sensor connection unit, and the fixed resistor is connected in parallel with the thermistor.

[0013] When a sudden temperature change causes overcurrent or overvoltage, setting a fixed resistor in parallel with the thermistor temperature sensor allows the fixed resistor to act as a current shunt and voltage divider. In overcurrent conditions, the fixed resistor shunts the current, reducing the current load on the thermistor; in overvoltage conditions, the fixed resistor divides the voltage, reducing the thermistor's voltage withstand capability. Furthermore, the stable resistance value of the fixed resistor can compensate for the nonlinear characteristics of the thermistor, making it more reliable during normal operation and providing additional protection in abnormal conditions.

[0014] According to a preferred embodiment, the fixed resistor is soldered to the terminals of the sensor connection unit.

[0015] According to a preferred embodiment, the connection terminal is electrically connected to other components at one end and connected to the pins of the thermistor at the other end.

[0016] According to a preferred embodiment, the sensor connection unit and the protective shell are fixed together by a press-fitting method.

[0017] According to a preferred embodiment, a seal is provided between the sensor connection unit and the protective housing.

[0018] According to a preferred embodiment, a thermally conductive medium is disposed between the protective shell and the thermistor.

[0019] According to a preferred embodiment, the thermally conductive medium is a thermally conductive adhesive.

[0020] According to a preferred embodiment, the thermistor is a negative temperature coefficient thermistor. Attached Figure Description

[0021] Figure 1 This is a cross-sectional view of a thermistor temperature sensor in the prior art.

[0022] Figure 2 This is an exploded view of the thermistor temperature sensor according to this utility model.

[0023] Figure 3 This is a cross-sectional view of the thermistor temperature sensor according to the present invention.

[0024] Figure 4 This is a cross-sectional view of the connection terminal with a fixed resistor according to the present invention.

[0025] Figure 5 This is a cross-sectional view of the fixed resistor of this utility model welded to the connecting terminal.

[0026] List of reference numerals

[0027] 1. Thermistor Temperature Sensor

[0028] 2 Sensor Connection Unit

[0029] 21 connection terminals

[0030] 22 shell

[0031] 23 Fixed resistors

[0032] 3 protective cases

[0033] 4 seals

[0034] 5 Thermistors

[0035] 51-pin

[0036] 7 Thermal conductive medium

[0037] 10. Thermistors with leaded pins in the prior art

[0038] 20 Leads of thermistors in the prior art

[0039] 30 Connection terminals in the prior art Detailed Implementation

[0040] The thermistor temperature sensor 1 according to the present invention will now be described with reference to the accompanying drawings and specific embodiments. However, exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the present invention comprehensive and complete, and to fully convey the concept of exemplary embodiments to those skilled in the art.

[0041] Figure 1 A thermistor temperature sensor according to the prior art is shown. It utilizes a typical negative temperature coefficient thermistor 10 as the temperature sensing element, which has two thin leads 20. Thermistor 11 is connected to a connection terminal 30 via these two leads 20, thereby achieving electrical connection of the thermistor. Thermistor temperature sensors used in various scenarios such as automobiles operate in harsh environments, where sudden temperature changes are common, leading to overcurrent or overvoltage effects that can damage the thermistor.

[0042] Figure 2 and 3 A thermistor temperature sensor 1 according to the present invention is shown. The thermistor temperature sensor 1 includes a sensor connection unit 2 and a protective housing 3. The sensor connection unit 2 includes a connection terminal 21 and a housing 22. One end of the connection terminal 21 is electrically connected to a thermistor 5 via a pin 51. At the same time, a fixed resistor 23 is provided on the connection terminal 21, forming a parallel relationship with the thermistor 5.

[0043] Here, a fixed resistor 23, which is connected in parallel with the thermistor 5, is mounted on the connection terminal 21 by welding.

[0044] The thermistor temperature sensor 1 also includes a protective housing 3, which is designed to form an internal cavity for accommodating the thermistor 5. The thermistor 5 is fixed within this cavity using a thermally conductive medium 7, particularly thermally conductive adhesive. This thermally conductive medium 7 facilitates a thermally conductive connection between the thermistor 5 and the protective housing 3.

[0045] Here, the thermistor 5 is provided with pins 51, which are connected to the connection terminal 21 via the pins 51, and the connection can be made by soldering. The thermistor 5 is, for example, made of two or three metal oxides and calcined in clay to form a dense structure.

[0046] When the thermistor temperature sensor 1 is assembled as a whole, the protective shell 3 is sleeved on the end of the sensor connection unit 2 near the thermistor 5 and fixed to the end of the sensor connection unit 2 by compression fitting. In order to achieve a seal between the sensor connection unit 2 and the protective shell 3, a sealing element 4 is provided between the sensor connection unit 2 and the protective shell 3.

[0047] at last, Figure 4 and 5 A perspective view of the connection terminal 21 with a fixed resistor 23 is shown. Figure 5 In the middle, two pins extend from both sides of the fixed resistor 23 and are connected to the two terminals of the connection terminal 21 respectively, thus forming a parallel relationship with the thermistor 5.

[0048] This thermistor temperature sensor can be widely used in various fields, such as small household appliances or motor vehicles.

[0049] Those skilled in the art will readily conceive of other embodiments of this utility model upon considering the disclosure of the above embodiments. This application is intended to cover any variations, uses, or adaptations of this utility model that follow the general principles of this utility model and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this utility model are indicated by the appended claims.

Claims

1. A thermistor temperature sensor, comprising: The sensor connection unit (2) includes a connection terminal (21) and a housing (22) for connecting a temperature sensor to other components. Protective shell (3), Thermistor (5) is disposed inside the protective housing (3). Pin (51), which connects the thermistor (5) and the connection terminal (21) in the sensor connection unit (2), Its features are, A fixed resistor (23) is provided on the connection terminal (21) in the sensor connection unit (2), which forms a parallel relationship with the thermistor (5).

2. The thermistor temperature sensor according to claim 1, characterized in that, The fixed resistor (23) is soldered to the connection terminal (21) of the sensor connection unit (2).

3. The thermistor temperature sensor according to claim 1, characterized in that, The connection terminal (21) is electrically connected to other components at one end and connected to the pin (51) of the thermistor (5) at the other end.

4. The thermistor temperature sensor according to claim 1, characterized in that, The sensor connection unit (2) and the protective shell (3) are fixed to each other by compression.

5. The thermistor temperature sensor according to claim 1, characterized in that, A sealing element (4) is provided between the sensor connection unit (2) and the protective shell (3).

6. The thermistor temperature sensor according to claim 1, characterized in that, A thermally conductive medium (7) is provided between the protective shell (3) and the thermistor (5).

7. The thermistor temperature sensor according to claim 6, characterized in that, The thermally conductive medium (7) is a thermally conductive adhesive.

8. The thermistor temperature sensor according to claim 1, characterized in that, The thermistor (5) is a negative temperature coefficient thermistor.

Images