DE102018105183A1 - Chamber candle with Hall sensor device - Google Patents

Abstract

The invention relates to a chamber candle 1 for an internal combustion engine, comprising an at least partially electrically conductive base body 4 for fixing the chamber candle 1 to a combustion chamber of the internal combustion engine, wherein the base body 4 has a ground electrode 41, an insulator 3 with a Festsetzabschnitt 31, over the the insulator 3 is at least indirectly fixed to the main body 4, a center electrode 8, wherein the center electrode 8 is guided through the insulator 3 and together with the ground electrode 41 forms a placeable air radio link in the combustion chamber, wherein the insulator 3 is a measuring section 32 for a Hall sensor device. 5 via which a current flow through the center electrode 8 can be measured.

Description

The invention relates to a chamber candle for an internal combustion engine, comprising an at least partially electrically conductive base body for fixing the chamber candle to a combustion chamber of the internal combustion engine, wherein the base body has a ground electrode, an insulator having a Festsetzabschnitt over which the insulator is at least indirectly fixed to the body , A center electrode, wherein the center electrode is guided through the insulator and forms together with the ground electrode a placeable in the combustion air radio link.

It is already a chamber candle from the DE 101 44 976 A1 known. This has a base body, a clamping sleeve and an insulator with a center electrode. The center electrode forms an air radio link with a ground electrode in the combustion chamber of an internal combustion engine.

The invention has the object of providing a chamber candle in such a way that the wear of the chamber candle can be monitored.

The object is achieved according to the invention in that the insulator has a measuring section for a Hall sensor device, via which a current flow through the center electrode can be measured.

The Hall sensor device measures the ignition current via an electromagnetic field of the ground electrode. With the aid of evaluation electronics, the ignition energy can be calculated at a known ignition voltage. The Hall sensor device comprises in particular a Hall sensor and can consist exclusively of a Hall sensor.

The wear of the spark plug can be determined by the ignition energy, because the ignition energy provides information about the ignition process. The ignition energy measurement can thus determine when the spark plug must be replaced. In contrast to the prior art, the spark plug can therefore be replaced only when needed and not after a fixed time window. Thus, the spark plug can be replaced when it is actually worn

It may also be advantageous for this purpose if a measuring sleeve is provided which at least partially delimits and at least indirectly fixes a measuring space on the base body, wherein the Hall sensor device or the Hall sensor device and an evaluation unit for the Hall sensor device is placed in the measuring chamber. The measuring sleeve protects the Hall sensor device from damage and thus increases the life of the Hall sensor device. In this case, the measuring sleeve can in particular be fixed to the base body in a material-locking manner and, in particular, by welding. The determination can also be made positive or non-positive. In any case, the measuring sleeve can be released again, for which purpose, if necessary, a tool is needed.

Furthermore, it may be advantageous if the fixing section and the measuring section of the insulator are formed from different materials, wherein the measuring section is made of a hardened, electrical insulating material which can be introduced into the measuring sleeve in a liquid manner. The insulation material may be particularly elastic. The fixing portion may further be formed in particular of a ceramic. By separating the insulator into two sections, it is possible to subsequently retrofit the measuring section to already existing spark plugs. In this case, the structure by the initially viscous insulating mass is suitable for each spark plug model and also easy to perform. If the measuring sleeve is loosened again, the measuring section of the isolator can also be removed. This is particularly easy if the insulator is made of an elastic material.

It can also be advantageous if the material of the measuring section is a silicone compound. Silicone compound is on the one hand low and further advantageous in particular in terms of their insulating properties.

In addition, it may be advantageous if the Hall sensor device or the Hall sensor device and an evaluation unit for the Hall sensor device is provided within the measuring section of the insulator. By fixing in the initially liquid insulator mass installation is very simple. Furthermore, the Hall sensor device and the optional evaluation can be easily solved by this measure, since they are deducted with the removal of the measuring sleeve and the insulator with.

In this case, it may be advantageously provided that the center electrode has a first section which is guided through the fixing section, and the center electrode has a second section which is guided through the measuring section, wherein the first section is detachably connected to the second section electrically via a contact point is contacted. Thus, the center electrode can be subsequently extended. This simplifies the retrofitting of the Hall sensor device. The contact point may be provided in the region of the transition between the fixing section and the measuring section.

Of particular importance may be for the present invention, when the Hall sensor device comprises a ferrite core through which the Center electrode is guided, wherein the ferrite core defines a cavity, wherein a Hall sensor is placed in the cavity. The ferrite core may be wound by a wire, in particular a copper wire. As a result of the measures, the magnetic field is concentrated in the air gap and can therefore be measured better via the Hall sensor. The Hall sensor can also be connected via an amplifier circuit to the transmitter.

• 1 eine Schnittansicht der Kammerkerze.

Further advantages and details of the invention are explained in the patent claims and in the description and shown in the figure. It shows:

• 1 a sectional view of the chamber candle.

According to 1 has a chamber candle 1 a basic body 4 on. At the base body 4 are directly a clamping sleeve 2 and a measuring sleeve 7 set. The clamping sleeve 2 has a floor 21 on that together with a sidewall 22 an interior 24 limited. The clamping sleeve 2 is with an end area 25 the side wall 22 on the body 4 screwed.

In the interior 24 is an insulator 3 with a central axis M provided with a first shoulder 33 on the ground 21 the clamping sleeve 2 abuts and with a second shoulder 34 on a contact surface 42 of the basic body 4 is applied. The insulator 3 is set form-fitting in this sense, wherein the insulator 3 is set under preload.

Through the insulator 3 is a center electrode 8th led in a pre-combustion chamber 92 which leads from a cap 9 , the main body 4 and the insulator 3 is limited. The cap 9 has cap openings 91 on, over which a mixture to be ignited from a combustion chamber into the pre-combustion chamber 92 arrives. At the base body 4 is still a ground electrode 41 provided with the center electrode 8th in the pre-combustion room 92 forms an air radio link.

The insulator 3 also has a fixing section 31 and a measuring section 32 on. The fixing section 31 is made of a ceramic and has an opening 23 of the soil 21 from the clamping sleeve 2 guided. The measuring section 32 is made of a hardened silicone compound.

The measuring sleeve 7 partly forms a measuring room 71 out. The measuring room 71 is further through an upper portion of the Festsetzabschnitts 31 , the ground 21 and a lid 10 formed so that the measuring section 32 in the measuring room 71 is arranged. In the cured silicone composition is a Hall sensor device 5 for measuring a current through the center electrode 8th set. The Hall sensor device 5 has a ferrite core 51 on. The ferrite core 51 forms a cavity 52 in which a Hall sensor 53 is placed. Via an electrical connection, this is connected to an evaluation unit 6 connected. Not shown is a cable guide through the lid 10 for further reading of the measured data.

The center electrode 8th has a first section 81 and a second section 82 on. The first paragraph 81 and the second section 82 are detachable to each other at a contact point 83 contacted using an axial bias. The first paragraph 81 is through the setting section 31 of the insulator 3 led, the second section 82 is guided through the measuring section. The contact point 83 is just at the interface between the measuring section 32 and the setting section 31 ,

LIST OF REFERENCE NUMBERS

1

chamber candle

2

collet

21

ground

22

Side wall

23

opening

24

Interior of the clamping sleeve

25

end

3

insulator

31

Retaining portion

32

measuring section

33

first shoulder

34

second shoulder

4

body

41

ground electrode

42

contact surface

5

Hall sensor device

51

ferrite

52

cavity

53

Hall sensor

6

evaluation

7

measuring sleeve

71

measuring room

8th

center electrode

81

first section

82

second part

83

contact point

9

cap

91

cap openings

92

precombustion

10

cover

M

Center axis of the insulator

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10144976 A1 [0002]

Claims (7)

Chamber candle (1) for an internal combustion engine, comprising - an at least partially electrically conductive base body (4) for fixing the chamber candle (1) to a combustion chamber of the internal combustion engine, wherein the base body (4) has a ground electrode (41), - an insulator (3 ) having a fixing section (31), via which the insulator (3) is fixed at least indirectly to the base body (4), - a center electrode (8), wherein the center electrode (8) is guided through the insulator (3) and together with the ground electrode (41) forms an air radio link which can be placed in the combustion chamber, characterized in that the insulator (3) has a measuring section (32) for a Hall sensor device (5), via which a current flow through the center electrode (8) can be measured. Chamber candle (1) after Claim 1 , characterized in that a measuring sleeve (7) is provided, which is at least indirectly fixed to the base body (4) and at least partially delimits a measuring space (71), wherein the Hall sensor device (5) is placed in the measuring space (71). Chamber candle (1) after Claim 2 , characterized in that the Festsetzabschnitt (31) and the measuring section (32) of the insulator (3) are formed of different materials, wherein the measuring section (32) made of a liquid in the measuring sleeve (7) can be introduced, cured, electrical insulation material , Chamber candle (1) after Claim 3 , characterized in that the material of the measuring section (32) is a silicone compound. Chamber candle (1) after Claim 3 or 4 , characterized in that the Hall sensor device (5) within the measuring section (32) of the insulator (3) is provided. A chamber candle (1) according to any one of the preceding claims, characterized in that the center electrode (8) has a first portion (81) guided through the fixing portion (31) and the center electrode (8) has a second portion (82) passed through the sensing section (32), wherein the first section (81) is releasably contacted to the second section (82) electrically via a pad (83). Chamber candle (1) according to one of the preceding claims, characterized in that the Hall sensor device (5) has a ferrite core (51) through which the center electrode (8) is guided, wherein the ferrite core (51) defines a cavity (52), wherein a Hall sensor (53) is arranged in the cavity (52).

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