CN111564271A - Thermistor - Google Patents

Abstract

The invention relates to a thermistor which comprises a shell, wherein a chip is arranged in the shell, and the chip is contacted with the top of the inner side of the shell through clamping pieces which are arranged in the shell and positioned at two sides of the chip; the clamping piece is provided with a clamping part for clamping the chip, the clamping part extends out of the clamping piece from bottom to top, the connecting part of the clamping part and the clamping piece is the bottom of the clamping part, and the upper part of the clamping part is abutted against the two sides of the chip and fixes the chip on the top of the inner side of the shell through the friction force with the side surface of the chip. The invention has smaller installation size, provides clamping force from bottom to top for the chip, and can prevent the chip from shaking in the shell, thereby improving the shock resistance of the product, and meanwhile, the bottom of the shell is provided with the supporting point, so that the shell can be effectively prevented from interfering with other components on the circuit board, and the use stability of the product is improved.

Description

Thermistor

technical field

The invention relates to an electronic component, in particular to an inrush current suppression or motor starter box-type thermistor for vehicle-mounted MCU.

Background technique

With the development of science and technology, the demand for miniaturization and stability of product volume is increasing. Taking automotive products as an example, the current PSB products (inrush current suppression or motor starter box-type thermistors) used in automotive MCUs, the The size of the shell is 18*13.5*26.5mm, so it cannot meet the installation requirements well for some spaces with limited installation conditions; and, due to its structure itself, the PTC chip is suspended in the shell, so it is easy to cause earthquake resistance The effect is not good; at the same time, if the welding is not in place, it will cause the shell and other components on the installation board to interfere with each other, thereby affecting the overall performance of the product.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a thermistor, which has the characteristics of small size, good shock resistance, good stability and the like.

The technical solution adopted by the present invention to solve the technical problem is as follows: a thermistor, used for a vehicle-mounted MCU, comprising a casing, wherein a chip is arranged in the casing, and the chip is arranged in the casing and located between two sides of the chip. The clamping member on the side is in contact with the top of the inner side of the casing; the clamping member has a clamping portion for clamping the chip, and the clamping portion extends from the clamping member in a bottom-up state to clamp the chip. The connection part between the part and the clamping part is the bottom of the clamping part, and the upper part of the clamping part abuts on both sides of the chip and fixes the chip on the top inside the casing by friction with the side of the chip. In this way, in addition to the clamping force, the chip can be provided with a force against sliding of the chip, so that the chip can be better protected from shaking, and the vibration requirements specified by the vehicle can be better met.

Further, the clamping piece also has an extension portion extending out of the casing, and the extension portion is provided with a clip which can be inserted into the welding position of the PCB circuit board and fixed with the lower surface of the PCB circuit board; the There is a gap between the top of the clip and the bottom of the housing, and the height of the gap is equal to the thickness of the PCB circuit board.

Still further, the bottom of the casing of the present invention is provided with protrusions, the height of the protrusions is 0.1 to 1 mm, and the protrusions are evenly distributed on the bottom of the casing, which can prevent interference when the product is not stuck. to other components on the circuit board, further improving the stability of the solder installation.

Furthermore, the casing of the present invention includes an integrally formed upper casing and a bottom cover arranged at the bottom of the upper casing. space size requirements.

Furthermore, the clamping piece of the present invention is a metal piece, and the clamping portion and the clamping feet are metal elastic pieces punched out by the clamping piece itself, so that the deformation performance of the metal elastic piece itself can be improved. to assemble.

The beneficial effects of the present invention are that it solves the defects existing in the background technology, has a smaller installation size, and provides a bottom-up clamping force for the chip, which can prevent the chip from shaking in the casing, thereby improving the shock resistance of the product At the same time, setting a support point at the bottom of the casing can effectively prevent the casing from interfering with other components on the circuit board, providing the stability of the product in use.

Description of drawings

Figures 1-4 are schematic structural diagrams of the present invention;

Fig. 5 is the installation schematic diagram of the present invention and circuit board;

6 is a schematic structural diagram of another embodiment of the present invention;

In the figure: 1. Housing; 2. Chip; 3. Clamping part; 4. Protrusion; 5. Circuit board; 11. Upper housing; 12. Bottom cover; 31. Clamping part; 32. Extension part; 33. Card foot.

Detailed ways

The present invention will now be described in further detail with reference to the accompanying drawings and preferred embodiments. These drawings are all simplified schematic diagrams, and only illustrate the basic structure of the present invention in a schematic manner, so they only show the structures related to the present invention.

As shown in Figures 1-4, a thermistor used in a vehicle-mounted MCU includes a casing 1. The casing 1 includes an integrally formed upper casing 11 and a bottom cover 12 disposed at the bottom of the upper casing 11. The said The size of the shell is less than or equal to 17 × 17 × 22.1mm, so that it can meet the requirements of smaller space size.

A chip 2 is disposed in the casing 1 , and the chip 2 is in contact with the top of the inner side of the casing 1 through the clamping members 3 disposed in the casing 1 and located on both sides of the chip 2 . According to other embodiments, the chip 2 can also be in contact with the top and the bottom cover of the casing 1 at the same time.

As shown in FIG. 2 , the clamping part 3 has a clamping part 31 for clamping the chip and an extension part 32 extending out of the casing 1 , the clamping part 3 is a metal part, and the extension part 32 is provided with a part that can be inserted into the PCB circuit board 5 . The clips 33 at the welding position and fixed to the lower surface of the PCB circuit board 5; the clips 33 in FIG. 2 are bent inwards, but if the size of the casing is reduced, the inwardly bent clips may form a three-dimensional obstacle , which may prevent the bottom cover from covering the casing. Therefore, according to other embodiments, the clamping legs 33 can also be bent outwards, as shown in FIG. 6 ; The metal dome is punched out by itself. Therefore, the clamping part 31 extends from the bottom to the top of the clamping part 3. The bottom of the clamping part 31 is connected with the clamping part 3 as a connecting part, and the upper part of the clamping part 31 is against the clamping part 3. The chip 2 is fixed on the top of the inner side of the casing 1 on both sides of the chip 2 and through frictional force with the surface of the chip. In this way, in addition to the clamping force, the chip can be provided with a force against sliding of the chip, so that the chip can be better protected from shaking, and the vibration requirements specified by the vehicle can be better met.

There is a gap between the top of the clip 33 and the bottom of the housing 1 , and the height of the gap is equal to the thickness of the PCB circuit board 5 . As shown in Figure 5, through such a welding installation method, there is no gap between the product and the circuit board after installation, which can improve the stability of fixing the product and the PCB circuit board. Moreover, the bottom of the casing 1 is provided with a protrusion 4, which can be integrally formed with the bottom cover of the casing, the height of the protrusion 4 is 0.1 to 1 mm, and the protrusion 4 is evenly distributed on the bottom of the casing, The protrusions play the role of support points; as shown in Figures 1 and 4, the protrusions 4 are distributed at the bottom of the casing in a rectangular shape, which can prevent the product from interfering with other components on the circuit board when it is not stuck, and further improves the soldering process. Stability during installation.

The reason why the present invention can realize miniaturization is:

(a) The existing housing needs a fixing member to fix the clamping member. The fixing member will form a bump inside the housing. It is necessary to design the accommodating space for the bump inside the housing, so that the volume of the housing cannot be Zoom out. The present invention does not require additional fixing parts to fix the clamping parts, and can reduce the volume of the casing.

(b) The material of the casing is changed from bakelite (phenolic resin) to LCP (liquid crystal polymer) with higher dielectric strength. Therefore, even if the thickness of the casing is reduced, the same voltage-resistant insulation effect can be achieved. In addition, LCP has good bendability, which is convenient for combined design and can meet the purpose of miniaturization.

What is described in the above specification is only the specific embodiment of the present invention, and various examples do not limit the essential content of the present invention. Those of ordinary skill in the art can modify or modify the specific embodiment described above after reading the specification. variations without departing from the spirit and scope of the invention.

Claims (6)

1. A thermistor, comprising a housing, characterized in that: the chip is arranged in the shell and is contacted with the top of the inner side of the shell through clamping pieces which are arranged in the shell and positioned at two sides of the chip; the clamping piece is provided with a clamping part for clamping the chip, the clamping part extends out of the clamping piece from bottom to top, the connecting part of the clamping part and the clamping piece is the bottom of the clamping part, and the upper part of the clamping part is abutted against the two sides of the chip and fixes the chip on the top of the inner side of the shell through the friction force with the side surface of the chip.

2. A thermistor according to claim 1, characterized in that: the clamping piece is also provided with an extension part extending out of the shell, and the extension part is provided with a clamping pin which can be inserted into the welding position of the PCB and is fixed with the lower surface of the PCB; a gap is formed between the top of the clamping pin and the bottom of the shell, and the height of the gap is equal to the thickness of the PCB circuit board.

3. A thermistor according to claim 1, characterized in that: the bottom of the shell is provided with bulges which are uniformly distributed at the bottom of the shell.

4. A thermistor according to claim 3, characterized in that: the height of the projection is 0.1 to 1 mm.

5. A thermistor according to claim 1, characterized in that: the shell comprises an integrally formed upper shell and a bottom cover arranged at the bottom of the upper shell, and the size of the shell is less than or equal to 17 multiplied by 22.1 mm.

6. A thermistor according to claim 2, characterized in that: the clamping piece is a metal piece, and the clamping part and the clamping pin are metal elastic pieces punched by the clamping piece.

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