CN111276850A - Novel SMA type radio frequency coaxial connector - Google Patents

Abstract

The invention relates to a novel SMA type radio frequency coaxial connector, which comprises a first shell, a connecting threaded sleeve rotatably sleeved on the first shell, an inner conductor arranged in the first shell, an insulating assembly used for fixing the inner conductor in the first shell, a bushing arranged in the first shell and positioned behind the inner conductor, and a second shell connected with the rear end of the first shell and used for pressing the bushing in the first shell, wherein the bushing comprises a bushing section and a bushing second section formed by extending the rear end of the bushing section backwards along the axial direction of the connector, the inner diameter of the bushing section is smaller than that of the bushing second section, and the bushing section and the bushing second section are respectively provided with a welding through hole. When this connector carries out cable welding and assembles, the internal shield layer of cable, outer shielding layer respectively with one section of bush and bush two-stage process welded fastening, the stability on the internal shield layer of greatly increased cable can obtain better electrical property index, the high frequency performance of connector is better, can also guarantee the reliability of connecting.

Description

New SMA Type RF Coaxial Connector

technical field

The invention belongs to the technical field of radio frequency coaxial connectors, in particular to a novel SMA type radio frequency coaxial connector.

Background technique

Conventional RF coaxial connectors are divided into: microstrip RF coaxial connectors and mating coaxial cable RF connectors according to their uses. The structure of the mating cable type RF connector can be divided into: welding structure, crimping structure, and mounting structure.

For example, a SMA radio frequency coaxial connector disclosed in Chinese patent CN206742606U includes a casing, a first insulator and a second insulator are installed in the casing, a pin is installed in the first insulator, a slot is formed at the tail of the pin, and the first insulator is connected to the second insulator. The air medium is between the two insulators, the inner casing and the rear end of the second insulator are bushings, the inner conductor of the cable is welded and fixed by the insulator and the pin, the shielding layer of the cable and the bushing are welded and fixed, and the outer sheath of the cable is connected to the casing through screws. Threaded connection.

In order to obtain excellent shielding effect, the current RF coaxial cable usually adopts the structure of double shielding layers, and there is a non-metallic layer between the two shielding layers for excellent mechanical stability. In the current RF coaxial connectors, the bushing is usually fixed by welding with the outer shielding layer of the cable. However, in the process of RF signal transmission, the inner shielding layer is often the main role, and the inner shielding layer is not stable enough, resulting in poor high-frequency performance. , which makes the connector of the current welding structure unable to obtain better electrical performance indicators and connection reliability.

SUMMARY OF THE INVENTION

In order to solve the deficiencies in the prior art, the present invention provides an improved SMA type radio frequency coaxial connector.

In order to solve the above technical problems, the present invention adopts the following technical solutions:

An SMA type radio frequency coaxial connector, comprising a first shell, a connecting screw sleeve rotatably sleeved on the first shell, an inner conductor disposed in the first shell, and an inner conductor disposed in the first shell An insulating assembly for fixing the inner conductor in the first casing, a bushing disposed in the first casing and behind the inner conductor, and connected to the rear end of the first casing and using In order to press the bushing into the second housing in the first housing, the bushing comprises a bushing section extending along the axial direction of the connector and a rear end of the bushing section The inner diameter of the first section of the bushing is smaller than the inner diameter of the second section of the bushing, and the first section of the bushing is sequentially distributed along its circumferential direction. A welding through hole, and a plurality of second welding through holes are sequentially distributed along the circumferential direction of the second section of the bushing.

In a further embodiment, the second outer shell is sleeved on the bushing, and the outer surface of the front end of a section of the bushing protrudes outward along its radial direction to form an extension portion, and the extension portion is clamped between the front end of the second shell and the first shell.

In a further embodiment, a first blocking portion for restricting the bushing between the front end portion of the second housing and the first housing is formed on the inner side wall of the rear end of the first housing.

In further embodiments, the rear end portion of the bushing is located within the second housing.

In a further embodiment, the bushing further includes a third bushing segment formed by the rear end portion of the second bushing segment extending backward along the axial direction of the connector.

In a further embodiment, an inner thread is provided on the inner side wall of the rear end of the first casing, and an outer thread that can be screwed with the inner thread of the first casing is provided on the outer side surface of the front end of the second casing.

In a further embodiment, the insulating assembly includes an insulator sleeved on the inner conductor and located between the first shell and the inner conductor, and an insulator disposed behind the inner conductor and located on the inner conductor and the lining an insulating sheet between the sleeves, the bushing also presses the insulating sheet between the first shell and the front end of the bushing.

In a further embodiment, a second blocking portion for restricting the insulating sheet between the first housing and the front end portion of the bush is formed on the inner side wall of the rear end of the first housing.

Preferably, a step is formed concavely on the outer side of the front end of the insulator along the axial direction of the insulator, and the inner wall of the front end of the first casing is formed inwardly convex along the radial direction of the first casing to be able to cooperate with the step. The first boss is connected to the first boss, and the step cooperates with the first boss to prevent the insulator from sliding toward the front end of the connector and detaching from the first housing.

More preferably, the inner conductor includes a section of inner conductor located at the front end of the connector and extending along the axial direction of the connector, and the rear end of the section of inner conductor extends along the axial direction of the connector. The second inner conductor segment formed by extending backward and the third inner conductor segment formed by the rear end of the second inner conductor segment extending backward along the axial direction of the connector, and the outer diameter of the inner conductor segment is smaller than the outer diameter of the inner conductor segment. The outer diameter of the second section of the inner conductor, the outer diameter of the second section of the inner conductor is smaller than the outer diameter of the third section of the inner conductor, and the insulator is sleeved on the second section of the inner conductor and is in contact with the third section of the inner conductor catch.

Due to the application of the above-mentioned technical solutions, the present invention has the following advantages compared with the prior art:

The connector of the present invention arranges the bushing into a first bushing section and a second bushing section with different inner diameters, and sets welding through holes in the first bushing section and the second bushing section respectively. When the cable is welded and assembled, the inner shielding layer of the cable is The outer shielding layer is welded and fixed with the first section of the bushing and the second section of the bushing respectively, which greatly increases the stability of the inner shielding layer of the cable, can obtain better electrical performance indicators, and the high-frequency performance of the connector is better. reliability.

Description of drawings

1 is a schematic half-section structure diagram of an SMA type radio frequency coaxial connector according to a specific embodiment of the present invention;

2 is a cross-sectional structural schematic diagram of an insulator of an SMA type radio frequency coaxial connector according to a specific embodiment of the present invention;

3 is a schematic half-sectional structural diagram of an SMA type radio frequency coaxial connector after assembling a cable according to a specific embodiment of the present invention;

In the figure: 1, inner conductor; 1a, one section of inner conductor; 1b, two sections of inner conductor; 1c, three sections of inner conductor; 2, first shell; 2a, first boss; 2b, first blocking part; 2c, 2nd blocking part; 3, insulating sheet; 4, insulator; 4a, step; 4b, second boss; 4c, raised part; 5, bushing; 5a, one segment of bushing; 5b, two segment of bushing; 5c , three sections of bushing; 5d, first welding through hole; 5e, second welding through hole; 6, connecting screw sleeve; 7, second shell; 8, snap ring; 9, sealing ring; 10, cable; 10a, Cable core wire; 10b, inner shielding layer; 10c, outer shielding layer.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings:

The SMA type radio frequency coaxial connector shown in Figures 1 to 3 includes a first housing 2, a connecting screw sleeve 6 rotatably sleeved on the first housing 2, an inner conductor 1 arranged in the first housing 2, and a In the first casing 2, an insulating component for fixing the inner conductor 1 in the first casing 2, a bushing 5 arranged in the first casing 2 and behind the inner conductor 1, and sleeved on the bushing 5 and connected with The rear end of the first shell 2 is connected to the second shell 7 , and the second shell 7 is also used for pressing and fixing the bushing 5 in the first shell 2 .

Referring to FIG. 1 , the bushing 5 includes a bushing section 5a extending along the axial direction of the connector, and a second bushing section 5b formed by the rear end of the bushing section 5a extending backward in the axial direction of the connector and the third bushing section 5c formed by the rear end of the second bushing section 5b extending backward along the axial direction of the connector, the inner diameter of the first bushing section 5a is smaller than the inner diameter of the second bushing section 5b, and the inner diameter of the second bushing section 5b The inner diameter of the third section 5c of the bushing is smaller than the inner diameter of the third section 5c of the bushing, and the first section 5a of the bushing is sequentially distributed with a plurality of first welding through holes 5d along its circumferential direction, and the second section 5b of the bushing is sequentially distributed with a plurality of second welding through holes 5e along its circumference. Specifically, the numbers of the first welding through holes 5d and the second welding through holes 5e may be independently 2, 3, 4, or more than 4, depending on the cables to be welded. When assembling with an external cable, the inner shielding layer of the cable and the first section 5a of the bushing are welded and fixed through the first welding through hole 5d, and the outer shielding layer of the cable and the second welding through hole 5e passing through the second section 5b of the bushing are welded and fixed. The third section 5c is sleeved on the outer sheath of the cable.

An extension portion is formed on the outer surface of the front end of the bushing section 5a along its radial direction, and the extension portion is clamped between the front end portion of the second housing 7 and the first housing 2, and the first welding through hole 5d is located in the rear of the extension. The rear end of the third bush segment 5c is located in the second housing 7 .

In this example, the insulating assembly includes an insulator 4 sleeved on the inner conductor 1 and located between the first shell 2 and the inner conductor 1 and an insulating sheet disposed behind the inner conductor 1 and between the inner conductor 1 and the bushing 5 3. The bushing 5 also presses and fixes the insulating sheet 3 between the first housing 1 and the front end of the bushing 5 .

Specifically, on the inner wall of the rear end of the first housing 2, a first blocking portion 2b for restricting the bushing 5 between the front end portion of the second housing 7 and the first housing 2 and a The first blocking portion 2b is located behind the second blocking portion 2c for the second blocking portion 2c that restricts the insulating sheet 3 between the front end portion of the bushing 5 and the first housing 2 .

Referring to FIG. 2 , the outer side of the front end of the insulator 4 in this example is concavely formed along the axial direction of the insulator 4 to form a step 4a, and the inner wall of the front end of the first housing 2 is formed to be convex along the radial direction of the first housing 2 to form a step 4a. The step 4a is in contact with the first boss 2a in contact with the first boss 2a to prevent the insulator 4 from sliding toward the front end of the connector and being separated from the first housing 2 .

The height H of the step 4a in the axial direction of the insulator 4 is 0.2±0.05 mm.

A step is also formed on the outer side of the front end of the insulating sheet 3 along the axial direction of the insulating sheet 3 , and the step of the insulating sheet 3 is matched and abutted with the second blocking portion 2c.

In this example, the inner conductor 1 includes an inner conductor section 1a located at the front end of the connector and extending in the axial direction of the connector, and an inner conductor formed by the rear end of the inner conductor section 1a extending backward in the axial direction of the connector. The second section 1b and the third section 1c of the inner conductor formed by the rear end of the second section 1b of the inner conductor extending backward along the axial direction of the connector, the outer diameter of the first section 1a of the inner conductor is smaller than the outer diameter of the second section 1b of the inner conductor, and the inner conductor The outer diameter of the second section 1b is smaller than the outer diameter of the third section 1c of the inner conductor, and the insulator 4 is sleeved on the second section 1b of the inner conductor and abuts the front end of the third section 1c of the inner conductor.

A second boss 4b is formed on the inner side of the rear end surface of the insulator 4 along the axial direction of the insulator 4 to protrude outwardly. between the first shell 2 and the inner conductor 1 . The rear end of the third inner conductor section 1c is provided with a jack for inserting an external cable along its axial direction. The front end of the inner conductor section 1a is tapered, and the inner conductor section 1a is used as a pin.

Protrusions 4 c for pressing the insulator 4 against the inner conductor 1 and the first housing 2 are formed on the side surface of the rear end of the insulator 4 to protrude outward along the radial direction of the insulator 4 .

Specifically, the front end surface of the insulating sheet 3 is in contact with the rear end surface of the inner conductor 1, and the insulator 4 is sleeved on the second inner conductor section 1b of the inner conductor 1, so that the third section 1c of the inner conductor and the first shell 2 are placed between A cavity is formed, and the cavity is filled with air, so that an air transition is adopted between the insulator 4 and the insulating sheet 3 .

The inner wall of the rear end of the first casing 2 is provided with an inner thread, the inner thread is located behind the first blocking portion 2b, and the outer surface of the front end of the second casing 7 is provided with an outer thread that can be threadedly connected with the inner thread of the first casing 2.

In this example, the outer surface of the front end of the first housing 2 is provided with a first groove along its circumferential direction, and the inner side wall of the connecting screw sleeve 6 is provided with a second groove corresponding to the first groove. A snap ring 8 is arranged in the groove, and the first housing 2 and the connecting screw sleeve 6 are movably connected by the snap ring 8. Through the snap ring 8, the connecting screw bush 6 can be clamped at the front end of the first housing 2, and can be It is ensured that the connecting screw sleeve 6 can rotate relative to the first housing 2 .

Between the front end of the first housing 2 and the connecting screw sleeve 6 is an insertion groove, and a sealing ring 9 sleeved on the outside of the first housing 2 is arranged in the insertion groove.

In this example, the connecting screw sleeve 6 , the first shell 2 and the second shell 7 are all made of stainless steel, which improves the environmental resistance reliability of the connector. The connection screw sleeve 6 is provided with a lead sealing hole, which is fixed by a lead wire to improve the connection reliability.

Referring to FIG. 3 , the assembly process of the SMA type RF coaxial connector and the external cable 10 in this example is as follows: the cable 10 passes through the second housing 7 , and then a section 5a of the bushing is connected to the cable 10 through the first welding through hole 5d The inner shielding layer 10b is welded, the second section 5b of the bushing is welded to the outer shielding layer 10c of the cable 10 through the second welding through hole 5e, the insulating sheet 3 is sleeved on the cable core wire 10a, and then the cable core wire 10a is inserted The inner conductor 1 and the cable core wire 10a are welded into the jack at the rear end of the inner conductor 1, and then put into the first shell 2 with the insulator 4 installed together, and the inner conductor 1 is inserted into the insulator 4, and then the first shell 2 is installed. The second shell 7 is screwed with the first shell 2, and then the bushing 5 and the insulating sheet 3 are pressed between the first shell 2 and the second shell 7, so as to fix the insulator 4 and the inner conductor 1 in the first shell 2 . Then, the snap ring 8 is installed in the first groove, the sealing ring 9 is installed at the corresponding position of the front end of the first housing 2, and finally the connecting screw sleeve 6 is put on the front end of the first housing 2, so that the outer periphery of the snap ring 8 is locked. into the second groove, and the assembly is completed.

Through the above settings, the SMA type RF coaxial connector has the following advantages:

1) In this connector, when the cable is assembled by welding, the inner shield of the cable is shielded by setting the bushing into a first section of the bushing and a second section of the bushing with different inner diameters, and opening welding through holes in the first section of the bushing and the second section of the bushing respectively. The outer shielding layer and the outer shielding layer are respectively welded and fixed with the first section of the bushing and the second section of the bushing, which greatly increases the stability of the inner shielding layer of the cable, can obtain better electrical performance indicators, and the high-frequency performance of the connector is better. connection reliability.

2) The second shell of the connector is sleeved on the bushing, the rear end of the bushing is located in the second shell, and the welding part of the bushing is contained in the second shell, so that the later cable assembly can be bent and connected when in use. When the tail of the device is installed, the welding part will not be directly affected by external force, which enhances the reliability of its use.

3) The connector is provided with steps on the front end of the insulator to match the design of the first boss on the front end of the first shell. After the connector is assembled, the insulator can be fixed between the inner conductor and the first shell. It is reliable and convenient, and can fully guarantee the interface size of the connector. It also makes the insulator of the connector not fall when the temperature test is completed after the assembly is completed or when the ambient temperature changes. It can completely ensure reliable signal transmission and the assembly operation of the connector. Simple, improve the yield and work efficiency.

4) A second boss is used between the insulator and the inner conductor of the connector to abut the front end face of the third section of the inner conductor, and the rear end of the inner conductor is provided with an insulating sheet to press the inner conductor between the insulator and the insulating sheet. The inner conductor will neither shrink nor be displaced due to the movement of the inner conductor of the cable, thereby ensuring reliable transmission of signals when the assembled cable assembly is in use.

5) The step-dislocation compensation design is adopted between the inner conductor of the connector and the first shell, and the air transition is adopted in the rear section, which ensures the superior high-frequency electrical performance of the entire connector and makes the high-frequency electrical performance indicators ideal.

6) The front end of the insulating sheet of the connector adopts a step design, which further ensures the superior high-frequency performance of the entire connector, making the high-frequency electrical performance indicators ideal.

In short, when the connector is assembling the cable, the connector and the cable with double shielding layer are reliably welded together, which greatly increases the stability of the inner shielding layer of the cable, and can obtain better electrical performance indicators. The high-frequency performance of the connector is better. Well, it can also ensure the reliability of the connection, improve the yield of the connector assembly, and improve the work efficiency.

The above-mentioned embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose thereof is to enable those who are familiar with the art to understand the content of the present invention and implement them accordingly, and cannot limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included within the protection scope of the present invention.

Claims (10)

1. The utility model provides a SMA type radio frequency coaxial connector, includes first shell, rotates the cover and establishes connect swivel nut on the first shell, set up inner conductor in the first shell, set up be used for in the first shell with the inner conductor is fixed insulating module in the first shell, set up in the first shell and be located the bush at inner conductor rear and with the rear end of first shell is connected and is used for with the bush is pressed and is established second shell in the first shell, its characterized in that: the bush includes the edge the axial direction of connector extends the bush that sets up one section and by one section back tip of bush is followed the axial of connector extends the bush two-section that forms backward, one section internal diameter of bush is less than the internal diameter of bush two-section, a plurality of first welding through-holes that distribute gradually along its circumferencial direction for one section of bush, a plurality of second welding through-holes that distribute gradually along its circumferencial direction for the bush two-section.

2. The SMA-type radio frequency coaxial connector of claim 1, wherein: the second shell is sleeved on the bushing, the outer side face of the front end of one section of the bushing protrudes outwards along the radial direction of the bushing to form an extending part, and the extending part is clamped between the front end of the second shell and the first shell.

3. The SMA-type radio frequency coaxial connector of claim 2, wherein: a first blocking part for limiting the bushing between the front end part of the second shell and the first shell is formed on the inner side wall of the rear end of the first shell.

4. The SMA-type radio frequency coaxial connector of claim 2, wherein: the rear end of the bushing is located within the second housing.

5. The SMA-type radio frequency coaxial connector of claim 2, wherein: the bushing also includes a third bushing segment formed by extending a rear end of the second bushing segment rearward in an axial direction of the connector.

6. The SMA-type radio frequency coaxial connector of claim 1, wherein: the rear end inner side wall of the first shell is provided with an internal thread, and the front end outer side face of the second shell is provided with an external thread which can be in threaded connection with the internal thread of the first shell.

7. An SMA type radio frequency coaxial connector according to any one of claims 1-6, wherein: insulating assembly establishes including the cover establish on the inner conductor and be located insulator and setting between first shell and the inner conductor are in the inner conductor rear just is located insulating piece between inner conductor and the bush, the bush still will insulating piece pressure is established first shell with between the front end of bush.

8. The SMA-type radio frequency coaxial connector of claim 7, wherein: a second stopper portion for restricting the insulating sheet between the first housing and the front end portion of the bushing is formed on a rear end inner side wall of the first housing.

9. The SMA-type radio frequency coaxial connector of claim 7, wherein: the outer side of the front end of the insulator is inwards concave along the axial direction of the insulator to form a step, a first boss which can be matched and abutted with the step is inwards convex along the radial direction of the first shell on the inner wall of the front end of the first shell, and the step is matched and abutted with the first boss to prevent the insulator from sliding towards the front end of the connector and separating from the first shell.

10. The SMA-type radio frequency coaxial connector of claim 9, wherein: the inner conductor comprises an inner conductor section, an inner conductor second section and an inner conductor third section, wherein the inner conductor section is located at the front end of the connector and extends along the axial direction of the connector, the inner conductor second section is formed by extending the rear end part of the inner conductor section backwards along the axial direction of the connector, the inner conductor third section is formed by extending the rear end part of the inner conductor second section backwards along the axial direction of the connector, the outer diameter of the inner conductor first section is smaller than that of the inner conductor second section, the outer diameter of the inner conductor second section is smaller than that of the inner conductor third section, and the insulator is sleeved on the inner conductor second section and is abutted to the inner conductor third section.

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