CN102707018A

CN102707018A - Gas sensor

Info

Publication number: CN102707018A
Application number: CN2012101985270A
Authority: CN
Inventors: 肖�琳; 倪铭; 陈凯; 尹亮亮; 邵兴隆
Original assignee: Wuxi Longsheng Technology Co Ltd
Current assignee: Wuxi Longsheng Technology Co Ltd
Priority date: 2012-06-17
Filing date: 2012-06-17
Publication date: 2012-10-03

Abstract

The invention discloses a gas sensor. The gas sensor comprises a base and a chip arranged in the base, wherein the two ends of the chip extend out of the base; a first ceramic tube, a seal powder embryo and a second ceramic tube are respectively sleeved on the chip in the base; an inner protective cover and an outer protective cover are arranged on the outer ring of one section, which extends out of the base, close to the first ceramic tube of the chip; the other end of the chip is close to the second ceramic tube; a sleeve is arranged on the second ceramic tube and the outer ring of one section, which extends of the base, of the chip; a taper washer is arranged at the end of the second ceramic tube; a catching groove which is protruded toward an inner ring is arranged on the sleeve; and the bump of the catching groove is buckled closely and jointed with the tapered surface of the taper washer. The difficulty of the gas sensor in quantifying the seal powder embryo precisely is reduced; the yield of the tightness of the gas sensor is improved; and the damage to a sensing element caused by the gas sensor in sealing and pressing processes can be prevented.

Description

Gas sensor

Technical field

The present invention relates to a kind of gas sensor, relate in particular to the encapsulating structure of gas sensor.

Background technology

Gas sensor is very important sensor in the Hyundai Motor, is contained in usually in the exhaust system, detects the content and the concentration of exhaust.As shown in Figure 2, gas sensor is contained on the waste pipe through the screw thread on the pedestal 1, and exhaust directly contacts with an end of chip 5 with air hole on the interior guard shield 9 through outer shield 8, and exhaust can not be leaked to the other end of chip 5.Therefore make the process of gas sensor, need be with an end and extraneous sealing of sensing unit contact exhaust, common method for packing is as shown in Figure 1; In sensor base 1, load onto first ceramic pipe 2 and chip 5 earlier, fill out sealing powder embryo 3 again, it is compressed with second ceramic pipe 4; After shrinking, sealing powder embryo 3 pressurizeds, buckle a sleeve pipe 6 simultaneously, the draw-in groove 1a place of tightening up at pedestal 1 with chip 5 sealings; Second ceramic pipe 4 is fixing, and chip 5 just is sealed in the sealing powder embryo 3 like this.

But when using this structure, the sealing powder embryo is tightened to position limit on the pedestal draw-in groove to the seal degree of sensing unit by sleeve pipe, and quantitative sealing powder embryo is inserted in this requirement, if sealing powder lack, after tightening up, the sealing powder embryo is inner loose, leaks gas easily; Sealing powder is many, and metal shell cannot close up, and perhaps can press to such an extent that too tightly sensing unit is damaged.

Summary of the invention

Technical matters to be solved by this invention provides a kind of pressure control of tightening up and can sensing unit sealed tightly; Do not damage simultaneously the scope of sensing unit again; Even the sealing powder embryo amount of inserting has deviation; Produce ceramic skew of tightening up the position, also do not influence metal shell the fixing gas sensor of tightening up of pottery.

Above-mentioned requirements is accomplished through following scheme:

A kind of gas sensor; Comprise pedestal, be arranged on the chip in the pedestal, pedestal is stretched out at the two ends of chip, is respectively installed with first ceramic pipe, sealing powder embryo, second ceramic pipe on the chip in the pedestal; Chip is provided with interior guard shield and outer shield near one section outer ring that first ceramic pipe stretches out pedestal; The other end of chip is near second ceramic pipe, and one section outer ring that second ceramic pipe and chip stretch out pedestal is provided with sleeve pipe, and the end of second ceramic pipe is provided with taper washer; Sleeve pipe is provided with to the protruding catching groove of inner ring, and the conical surface fastening of the convexity of catching groove and taper washer is fitted.

Beneficial effect: do not have fixing draw-in groove position on the pedestal of gas sensor of the present invention; But at pipe of pedestal mouth welding; On ceramic pipe, fill up a taper washer earlier; After certain pressure compresses the sealing powder embryo, be provided with on the sleeve pipe to the protruding catching groove of inner ring, the conical surface fastening of the convexity of catching groove and taper washer is fitted.Reduced gas sensor to the accurate quantitative difficulty of sealing powder embryo, improved the qualification rate of gas sensor sealing, can prevent that gas sensor from press-fiting damage first to sensing in the process in sealing.

Description of drawings

Fig. 1 is traditional gas sensor chip encapsulating structure;

Fig. 2 is the structural representation of gas sensor of the present invention;

Fig. 3 is the part synoptic diagram before the gas sensor sealing of the present invention;

Fig. 4 is a gas sensor encapsulating method synoptic diagram of the present invention;

Fig. 5 is the part-structure synoptic diagram after the gas sensor sealing of the present invention.

Among the figure: 1-pedestal, 2-the first ceramic pipe, 3-sealing powder embryo, 4-the second ceramic pipe, 5-chip, 6-sleeve pipe, 6a-catching groove, 7-taper washer, 8-outer shield, 9-interior guard shield, 10-wire harness assembly, a-positioning tool, b-buckle the plumber to adorn.

Embodiment

Further specify technical scheme of the present invention below in conjunction with accompanying drawing.

A kind of gas sensor; Comprise pedestal 1, be arranged on the chip 5 in the pedestal 1, pedestal 1 is stretched out at the two ends of chip 5, is respectively installed with first ceramic pipe 2, sealing powder embryo 3, second ceramic pipe 4 in the pedestal 1 on the chip 5; Chip 5 is provided with interior guard shield 9 and outer shield 8 near one section outer ring that first ceramic pipe 2 stretches out pedestal 1; The end that one section outer ring that the other end of chip 5 stretches out pedestal 1 near second ceramic pipe, 4, the second ceramic pipes 4 and chip 5 is provided with sleeve pipe 6, the second ceramic pipes 4 is provided with taper washer 7; Sleeve pipe 6 is provided with to the protruding catching groove 6a of inner ring, and the conical surface fastening of the convexity of catching groove 6a and taper washer 7 is fitted.

As shown in Figure 3; Weld the sleeve pipe 6 of a metal material earlier in gas sensor pedestal 1 port; Chip 5 is put into pedestal 1 corresponding center, and first ceramic pipe 2, sealing powder embryo 3, second ceramic pipe 4, taper washer 7 are enclosed within chip 5 upper edge sleeve pipes 6 successively and put into pedestal 1 inner chamber.Method for packing is as shown in Figure 4, withstands taper washer 7 with positioning tool a, acts on the pedestal 1 with certain pressure, and the pressure settings is just in time can the sealing of sensing unit tightly and not to be damaged the body of sensing unit.With after the sealing tightly of sensing unit,, adorn b with the button plumber and tighten up metal sleeve 6 after sealing powder embryo 3 is squeezed and shrinks in the position that positioning tool a pushes down taper washer 7.It is as shown in Figure 5 to tighten up back making-up unit, and taper washer 7 is by closing in place of sleeve pipe 6 restriction, and sleeve pipe 6 forms to be gone up to the protruding catching groove 6a of inner ring, the snap-in force that second ceramic pipe 4 is kept sealing powder embryo 3.Even the amount of sealing powder embryo 3 has deviation like this, also just changed the closing in position of catching groove 6a on the sleeve pipe 6, but can be through sealing and the protection of encapsulation pressure control to sensing unit 5.

Claims

1. gas sensor; Comprise pedestal (1), be arranged on the chip (5) in the pedestal (1); Pedestal (1) is stretched out at the two ends of chip (5); Be respectively installed with first ceramic pipe (2), sealing powder embryo (3), second ceramic pipe (4) on the interior chip of pedestal (1) (5), chip (5) is provided with interior guard shield (9) and outer shield (8) near one section outer ring that first ceramic pipe (2) stretches out pedestal (1), and the other end of chip (5) is near second ceramic pipe (4); One section outer ring that second ceramic pipe (4) and chip (5) stretch out pedestal (1) is provided with sleeve pipe (6); It is characterized in that: the end of said second ceramic pipe (4) is provided with taper washer (7), and sleeve pipe (6) is provided with to the protruding catching groove (12) of inner ring, and the conical surface fastening of the convexity of catching groove (12) and taper washer (7) is fitted.