JPS5939624Y2 - temperature measuring device - Google Patents

Description

[Detailed Description of the Invention] This invention mainly relates to a temperature measuring device for measuring the temperature inside an engine, and is particularly characterized in that a lead wire for taking out a measurement signal is directly attached to the engine body.

Conventionally, a thermocouple is used to measure the surface temperature of an engine, especially inside the combustion chamber, but the thermocouple has a lead wire connected to it to extract the measurement signal, and it is not possible to easily extend it from within the engine body. I was in trouble.

This idea was devised in view of the above circumstances, and by attaching the lead wire to the engine body in an electrically insulated state in advance, the measurement signal detected by the thermocouple can be easily extracted from inside the engine. It is an object of the present invention to provide a temperature measuring device according to the present invention.

This invention will be described in detail below with reference to an illustrated embodiment.

FIG. 1 is a schematic diagram of the engine viewed from above, with 1 being the engine body, 2 being a plurality of cylinders formed within the engine body 1, and the upper openings of these cylinders 2 being closed by the cylinder head 3. In addition, the cylinder head 3 is provided with an injection nozzle 4 for each cylinder 2, and an intake hole 5, an exhaust hole 6, etc. are formed around the injection nozzle 4.

The bell 7 is a temperature detection element such as a thermocouple embedded in the circumference of the cylinder 2 or the cylinder head 3 to measure the temperature of the engine body 1, especially the inner surface of the cylinder 2. It is connected via a line 8 to a measuring device (not shown) provided outside the engine body 1.

Further, the lead wire 8 is embedded in a part of the engine body 1 in the following manner.

That is, a groove 9 as shown in FIG. 2 is formed in the outer circumference 1 of the engine body 1 by the temperature detection element 7, and by plasma spraying aluminum oxide or the like on the inner surface of the groove 9. An insulating layer 10 is formed.

After the lead wires 8 to be buried above the insulating layer 10 are laid, an insulating layer 10 of aluminum oxide or the like is further thermally sprayed so that the lead wires 8 are surrounded by the insulating layer 10 and the grooves 9 are also buried. Ru.

If a large number of lead wires 8 are to be taken out at the same time, the insulating layer 10 may be provided over a large number of layers as shown in FIG.

In addition, when one side of the single conductor wire 8 is taken out using the engine body 1, if the engine body 1 has variations in composition such as cast iron, the measurement accuracy will be reduced.

In such a case, as shown in Fig. 4, a thin layer of pure iron or the like is thermally sprayed onto the surface of the engine body 1 to form a common lead wire 8a, and the lead wire 8 is laid on top of this using the same method as above. Bye.

As described in detail above, in this invention, an insulating layer 10 is formed in advance on the engine body 1 by plasma spraying, and this insulating layer 1
Since the lead wire 8 was buried inside the engine body 1
By connecting this lead wire 8 to the temperature detection element 7 provided inside, the signal detected by the temperature detection element 7 can be easily taken out to the outside of the engine body 1, and the insulation state of the lead wire 8 is reduced by heat. It doesn't get worse.

Further, since the insulating layer 10 is formed by plasma spraying, it can be easily applied to a large engine body 1 or an engine body with a complicated shape, and excellent durability against heat and vibration can be obtained.

Moreover, by making the insulating layer 10 multi-layered, a large number of lead wires 8 can be drawn out at the same time, and if the engine body 1 is made of cast iron, etc., if a common lead wire 8a such as pure iron is formed in advance and the button is pressed, the lead wires can be drawn out. The number of 8s can be halved.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention; Fig. 1 is a plan view of the engine body, Fig. 2 is an enlarged sectional view taken along the line ■-■ in Fig. 1, and Figs. 3 and 4 are other embodiments. FIG. 1 is the engine body, 7 is the temperature detection element, 8 is the lead wire,
10 is an insulating layer.

Claims (1)

[Scope of utility model registration request] A temperature detection element 7 is provided at the temperature measurement point of the engine body 1, and a groove 9 is formed along the first line 8 to guide the temperature signal detected by the temperature detection element 7 to the outside of the engine body 1. A temperature measuring device in which the lead wire 8 is embedded in an insulating layer 10 formed in a groove 9 by plasma spraying.