Abstract: A process is suggested for checking the catalyst performance in internal-combustion engines, in which by means of detected operating parameters of the internal-combustion engine similar operating conditions are determined. It is suggested to compute from a defined number of measured exhaust gas values during a similar operating condition a statistically backed average exhaust gas value and compare it with a permissible exhaust gas value stored for this operating condition, so that a defective catalyst is recognized in the event of a deviation of the actually determined exhaust gas value from the permissible exhaust gas value.

Abstract: A cylinder head for a direct-injection spark-ignition internal combustion engine includes, for each cylinder, an inlet valve, an exhaust valve, a first receptacle, a second receptacle, and a third receptacle. The first, second, and third receptacles are respectively configured to receive an ignition device or an injection device. The first receptacle extends substantially parallel to the inlet valve. The second receptacle extends substantially parallel to the exhaust valve. A common camshaft is offset from a cylinder center plane and actuates the inlet valve and the exhaust valve via identically constructed valve actuating elements. The cylinder head is lightweight, compact and easy to assemble and is in particular suited for high performance engines.

Abstract: The piston (1) has a ball receptacle (14) for the rod head (4) of the piston rod (2) of a swash plate compressor. For absorbing particularly high pressures the rod head (4) has a relatively large diameter, so that the ball receptacle (14) extends close to the circumference of the piston (1). The piston wall (15) laterally surrounding the rod head (4) has a circumferential indentation (21) which, in the inwards direction, forms an uninterrupted undercut enclosing the spherical rod head (4).

Abstract: The piston (1) has a ball receptacle (14) for the rod head (4) of the piston rod (2) of a swash plate compressor. For absorbing particularly high pressures the rod head (4) has a relatively large diameter, so that the ball receptacle (14) extends close to the circumference of the piston (1). The piston wall (15) laterally surrounding the rod head (4) has a circumferential indentation (21) which, in the inwards direction, forms an uninterrupted undercut enclosing the spherical rod head (4).

Abstract: The reciprocating engine more particularly intended for high pressure applications or motor vehicle CO.sub.2 air conditioning systems, has a wobble plate transmission, whose wobble plate (3) can assume different inclined positions for power control purposes. For this purpose is provided a wobble joint constructed as a knuckle joint, allowing the tilting movement of the wobble plate (3) supported on the engine shaft (4) through a slot guide (11, 11') of a driving pin (9). A good controllability of the reciprocating engine results from friction-reducing engine components provided on the driving pin (9) and comprising bearings (32, 33), which allow a rotation of the driving pin (9) about its longitudinal axis, as well as a sliding bush or a roller bearing (47) on one of the pin ends (40, 43) engaging in slot guides (11, 11'). In addition, in the vicinity of the more strongly loaded pin end is provided an axial force-absorbing sliding disk (42).

Abstract: The hub and spoked of a steering wheel consist of a synthetic thermoplastic resin and just as the rim are covered with a layer of a deformable plastic. To provide a steering wheel which is light in weight and has a high temperature stability, the hub and spokes consist of a polyamide which has been modified with elastomers and fibers.