Cylinder head gasket

#The invention concerns a cylinder head gasket of an internal combustion engine with a gasket sheet that contains at least one combustion chamber passage opening, wherein on the gasket sheet there is a sensor device for the registration of a measurement value that depends on the operating condition of the internal combustion engine.

#Such a cylinder head gasket of an internal combustion engine is known from EP 0 482 164 B1. The gasket sheet features a sensor device with several sensor elements, which are each fixed to the combustion chamber passage openings near the combustion chamber borders or combustion chamber sealing elements, e.g. glued into recesses that are press-molded into the bottom side of the gasket sheet. The sensor elements can be connected to a control unit and a monitoring unit by means of connecting lines and contact elements. The sensor elements measure movements of the sealing gap between the engine block and the cylinder head perpendicular to the plane of the gasket sheet that are caused by pressure changes in the corresponding combustion chamber area. Replacing a defective sensor element requires removal of the cylinder head gasket.

#From DE 691 06 081 T2 a cylinder head gasket of an internal combustion engine has become known that features a gasket sheet with at least one combustion chamber passage opening, wherein a pressure sensor is attached to the gasket sheet for the purpose of registering the combustion pressure inside the combustion chamber of the internal combustion engine. The pressure sensor is located in the cylinder head gasket near the combustion chamber and is pressurized by the combustion pressure via a pressure channel. A connecting line passes through the cylinder head gasket to a connecting element located on the external edge of the gasket.

#Below, the invention is more closely described based on embodiment examples and in reference to drawings. Shown are:

#FIG. 1 a partial top view of a cylinder head gasket according to the invention with a sensor module;

#FIG. 2 a partial top view of a gasket sheet of a cylinder head gasket with a connecting section for a sensor module;

#A cylinder head gasket 1, shown partially in FIG. 1 (see FIG. 1), features a gasket sheet 2 that is also called a carrier sheet. On the top side and/or the bottom side of the gasket sheet 2, additional gasket sheets can be located in a known fashion, such as, e.g., the upper gasket sheet 3 shown in the drawing, in order to build a multi-layer cylinder head gasket 1. In this type of design both the gasket sheet 2 and the other gasket sheets can feature ribbing and stoppers for the sealing of passage openings 4 for corresponding combustion chambers of the internal combustion engine.

#The gasket sheet 2 features a connecting section 5 (see FIG. 2) to which a sensor module 6 can be attached by plugging the sensor into the section (see the enlarged views of the FIGS. 3 through 6). The shown connecting section 5 is configured in the shape of a tongue at one free edge of the gasket sheet 2. The sensor module 6 features a socket 7 with a slit-shaped receptacle opening 8, which has a shape adapted to fit the tongue-shaped connecting section 5. The connecting section also features retaining fingers 9 that grip around the inserted connecting section 5 with elastic snap clamps 10 that have a corresponding retaining protrusion 12 that engage in two recesses 11 of the connecting section 5 when the sensor module 6 is positioned in its snap-locked and operating position on the gasket sheet 2. The gasket sheet 2 features, between the two recesses 11 on the connecting section 5, a measurement value registration position 13 in the form of bump that is formed toward the top side of the gasket sheet 2 and that is manufactured as a circular surface by means of stamping the gasket sheet 2. The sensor module 6 contains as a sensor element a thermal element 14 that is positioned in the retaining opening 8 in such a manner that a contact zone 15 of the thermal element 14 abuts directly against the measurement value registration position 13 when the sensor module 6 is positioned in its operating position on the gasket sheet 2 as shown in FIGS. 3 through 6. A connecting line 16 that is integrated into the sensor module 6 connects the contact zone 15 to two contact pins 17 of a connector element 18 of the sensor module 6 that is used to connect a line that is connected to a computer unit or to a motor control and monitoring unit.

#The embodiment example of a cylinder head gasket that is shown in FIGS. 7 through 12 differs from the previously described cylinder head gasket in the configuration of the sensor module 6′. The connecting section 5 of this gasket sheet 2 features an elongated slit-shaped recess 20 that extends from the connecting section 5 to near the combustion chamber passage opening 4 and that defines a forward measurement value registration position 13′. The sensor module 6′, which essentially has an identical structure as the sensor module 6 shown in FIGS. 1 through 6, contains a sensor element 14′ with an extended mounting bracket that extends in a lance-shaped manner forward from the retaining opening 8 at the socket 7 and is inserted into the recess 20 when the sensor module 6′ is attached, so that a measurement tip 21 of the sensor element 14′, e.g. a thermal element, is positioned at the forward measurement value registration position 13′. In this manner the sensor module 6′ can be connected to a distant measurement value registration position 13′.