JPS5928337Y2 - Exhaust temperature detection plug - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an exhaust temperature detection plug used in an automobile exhaust gas purification device.

An exhaust temperature detection plug using this type of thermocouple as a temperature detection element consists of a leek-hole insulating tube with a hot junction exposed at the tip and a thermocouple sealed, and a metal insulating tube with the insulated tube sealed on the inner diameter surface. an outer cylinder, and a tubular thermocouple that is loosely inserted into the insulating outer cylinder and is seated on a crotch seat provided on the inner wall of the exhaust gas purification device, the tip of which is locked to a large-diameter collar provided at the tip of the insulating outer cylinder. Since a small amount of hot liquid is exposed inside the exhaust gas purification device, it responds sensitively to temperature changes in the exhaust gas.However, in order to prevent the thermoelectric lamp from drooping during use, an insulating tube extending close to the hot junction of the thermocouple is installed. Since the head part had a long exposed part that protruded into the exhaust gas purification system, the brittle ceramic insulating tube could break at this exposed part even if it received a slight impact during assembly or handling, preventing damage. I was used to it.

The present invention has been made to solve the above-mentioned drawbacks, and the embodiments shown in the drawings will be described below.

In the figure, 1 is a high-temperature thermocouple made of alumel, chromel, etc. and has a hot junction 1a, and 2 is an insulating tube made of high alumina porcelain, etc., which has l pairs of through holes 2a into which the thermocouple 1 is inserted.

3 is a heat-resistant adhesive such as alumina cement that seals the thermocouple 1 inserted into the through hole 2a, and 4 is a metal outer cylinder that is bonded to the insulating tube 2 with a heat-resistant adhesive 5 such as alumina cement. A large-diameter collar 4a that sits on a crotch seat (not shown) on the inner wall of the provided opening, and a cover that extends in front of the collar 4a and protects the thermocouple 1 that protrudes into the exhaust gas purification device through the opening. Equipped with referee 4b.

Reference numeral 6 denotes a tubular tightening bolt that loosely fits into the metal outer cylinder 4 in the radial direction and locks in the axial direction with a large-diameter collar 4a provided on the metal outer cylinder. It has a screw 6a that is screwed into the opening and fastens the metal fitting outer cylinder 4 onto the crotch seat on the inner wall of the opening of the purifier.

Next, 7 is a wire that connects the thermocouple 1 to an external thermometer, and after connecting a general compensating conductor or a covered wire of the same quality as the thermocouple 1 by welding or brazing, the other end of the metal outer cylinder 4 is connected. It is protected by a joint 8 fixed by welding or brazing.

Reference numeral 9 denotes an insulating material made of talc, alumina powder, etc. filled in the joint 8.

Although the large-diameter flange 4a provided on the metal outer cylinder is formed by plastic working, it may also be turned, and although not shown, separately manufactured metal rings can be joined by welding, brazing, etc.

As described above, the present invention has an insulating tube that is exposed inside the exhaust gas purification device and protrudes near the hot junction of the thermocouple, and the diameter of the metal outer cylinder that is fastened to the seat at the crotch seat of the opening of the exhaust gas purification device is increased. Because it is covered with a cover extending from the brim of the pipe, even if it is subjected to external impact during assembly and handling, the cover absorbs it and has a great practical effect in protecting the brittle insulating pipe.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view of the exhaust temperature detection frame according to the present invention, Figure 2
The figure is a sectional view taken along line E in FIG. 1. 1...Thermocouple, 2...Insulated tube, 3 and 5...Heat-resistant adhesive, 4...Metal outer cylinder, 4a...・Large diameter tsuba, 4b...Summary, 6...Tightening bolt.

Claims (1)

[Scope of utility model registration request] Consisting of an insulating tube with a hot junction exposed at the tip and a thermocouple sealed therein, a metal outer tube with the insulated tube sealed on its inner diameter surface, and a tubular tightening bolt loosely inserted through the metal outer tube, A large-diameter flange is provided on the end face of the metal outer cylinder to sit on a crotch seat provided on the inner wall of the opening of the exhaust gas purification device and to lock the tubular tightening bolt. An exhaust temperature detection plug characterized by having an extended cover that protects an insulating pipe protruding into an exhaust gas purification device.