Abstract: In order to avoid over-lubrication of the cylinders (2) in a piston compressor (1) and to reduce the amount of lubricant to a level required for operation, according to the invention, a lubricating system having a lubricating system control unit (14) is provided, in which system at least one lubricant sensor (15) is provided for detecting a lubricating film measurement variable (S) representative of a lubricating film thickness of a lubricating film (11) on the cylinder surface of the cylinder (2), the lubricating system control unit (14) being designed to operate the lubricating system at least once in a predetermined calibration operating mode during operation of the piston compressor (1) and to determine a lubricating film state value (SZ) on the basis of the lubricating film measurement variable (S) detected during execution of the calibrating operating mode and the lubricating system control unit (14) being designed, after the end of the calibration operating mode during operation of the piston compresso

Abstract: High temperatures of the sealing medium occur in a hydraulic sealing medium barrier for sealing a piston rod of a piston compressor, and there is the risk of soil and abrasion being deposited there and interfering with the function of the seal. To prevent this, a sealing configuration (1) which is provided for circulating sealing medium through an outlet line (11) for sealing medium which is connected to the recess (10), and a circulating device (13) is provided, with which the sealing medium is circulated through the recess (10) while maintaining the pressure (poil) of the sealing medium through the inlet and the outlet line (7, 11).

Abstract: A fluid mixer in the form of a Venturi tube includes a divergent section (A2) with a steady contour curve having at least two inflection points (W1, W2) to reduce flow separations.

Abstract: High temperatures of the sealing medium occur in a hydraulic sealing medium barrier for sealing a piston rod of a piston compressor, and there is the risk of soil and abrasion being deposited there and interfering with the function of the seal. To prevent this, a sealing configuration (1) which is provided for circulating sealing medium through an outlet line (11) for sealing medium which is connected to the recess (10), and a circulating device (13) is provided, with which the sealing medium is circulated through the recess (10) while maintaining the pressure (poil) of the sealing medium through the inlet and the outlet line (7, 11).

Abstract: In a reciprocating piston compressor with delivery rate control, the electromagnetic actuating device (3) of the valve lifter (2) has a separate positioning drive (10) for adjusting the working stroke range of the magnetic actuator (5) used, whereby this can be chosen to be small and highly dynamic and only low power losses occur.

Abstract: Due to increasingly strict requirements and regulations, it is becoming more and more important for piston compressors to reduce the amount of leakage of operating medium through the seal of the piston rod. Conventional seals comprising packing rings and/or packing ring combinations always have a certain amount of leakage, both during operation and when at standstill, which is why they are not usable for certain applications, or the complexity involved in such a seal increases considerably. A further problem involving the seals of piston rods relates to transverse movements by piston rods during which the sealing action of the seal must be maintained. Proposed is, therefore, a sealing arrangement according to the principle of a sealing medium barrier providing that the sealing elements 8, 9 are arranged in radial direction at a distance relative to the radial end of the recess 10 that receives the sealing elements 8, 9.

Abstract: To reduce leakage of pressure medium in a seal arrangement (1) comprising two sealing elements (8) that are pressed by a sealing medium against the piston rod (3) and against a wall (11) of a recess (10), it is provided that the radially interiorly disposed circumferential surface (24) constitutes at least one of the sealing elements (8) from a sealing surface (12) and a tributary area (23), a second end face (21) that faces away from the axial end (11) of the recess (10) connecting to the sealing surface (12), and a rigid cover ring (9) being provided that is positioned at least in part radially against the radially exterior circumferential surface (25) of the sealing element (8) and at least in part axially against the second end face (21) of the sealing element (8).

Abstract: A fluid mixer in the form of a Venturi tube includes a divergent section (A2) with a steady contour curve having at least two inflection points (W1, W2) to reduce flow separations.

Abstract: In a reciprocating piston compressor with delivery rate control, the electromagnetic actuating device (3) of the valve lifter (2) has a separate positioning drive (10) for adjusting the working stroke range of the magnetic actuator (5) used, whereby this can be chosen to be small and highly dynamic and only low power losses occur.

Abstract: A gas-proof sealing packing of a compressor includes a scraper recess on the crankcase-side end containing a gas-proof scraper ring, a sealing ring recess on the cylinder-side end containing a sealing ring arrangement (18), a barrier recess located axially between the scraper recess (15) and the sealing ring recess (17), and a drain line in the sealing packing that is connected with the space between the barrier recess and the scraper recess.

Abstract: A segmented piston ring assembly includes piston ring segments 2 having stepped ends 5, 6, at least one piston ring segment 2 including a radial step on a radially inner peripheral surface 9 over a part of the width of the piston ring segment 2, and a single-cut sealing ring 3, which bears radially against the inside of the peripheral surface 9 of the piston ring segments 2, the sealing ring 3 including an axial recess 10, 12 which cooperates with the radial step 4 of the piston ring segment 2 to prevent relative rotation therebetween.

Abstract: A multipart packing ring for sealing a piston rod of a compressor includes ring segments and sealing segments which are alternatingly arranged to form a ring. The ring segments include a curved main part and an axial shoulder and the sealing segments include a curved main part and an axial projection. The circumferential ends of the main part of the ring segments and the circumferential ends of the axial projection of the sealing elements face one another and define first wear gaps there-between.

Abstract: Due to increasingly strict requirements and regulations, it is becoming more and more important for piston compressors to reduce the amount of leakage of operating medium through the seal of the piston rod. Conventional seals comprising packing rings and/or packing ring combinations always have a certain amount of leakage, both during operation and when at standstill, which is why they are not usable for certain applications, or the complexity involved in such a seal increases considerably. A further problem involving the seals of piston rods relates to transverse movements by piston rods during which the sealing action of the seal must be maintained. Proposed is, therefore, a sealing arrangement according to the principle of a sealing medium barrier providing that the sealing elements 8, 9 are arranged in radial direction at a distance relative to the radial end of the recess 10 that receives the sealing elements 8, 9.

Abstract: Conventional wiper arrangements with cut rings suffer from unavoidable leakage and, in particular in an embodiment as metallic wiper ring with a sharp wiping edge, scratch on the surface of the piston rod which can be damaged in this manner. In order to eliminate these problems, a wiper arrangement is proposed in which the radially inner circumferential surfaces 6, 7 of the wiper ring 2 and the cover ring 3 form a common radially inner wiping surface 10 and on the cover ring 3 or the on the wiper ring 2, an intake surface 8 is provided which is adjacent to the wiping surface 10 and which is inclined radially outwardly at an angle ?, preferably between 2° and 15°, with respect to the wiping surface 10.

Abstract: Conventional wiper arrangements with cut rings suffer from unavoidable leakage and, in particular in an embodiment as metallic wiper ring with a sharp wiping edge, scratch on the surface of the piston rod which can be damaged in this manner. In order to eliminate these problems, a wiper arrangement with a wiper ring 2 which is split in the circumferential direction and an L-shaped cover ring 3 which is split in the circumferential direction is proposed, wherein the splitting points 16, 15 of the cover ring 3 and the wiper ring 2 are arranged offset to each other in the circumferential direction, and the wiper ring 2 is arranged abutting axially as well as radially in the recess 4 of the L-shaped cover ring 3, and the radially inner circumferential surfaces 6, 7 of the wiper ring 2 and the cover ring 3 form a common radially inner wiping surface 10.

Abstract: A segmented packing ring 20 includes a number of first sealing segments 21, a number of second sealing segments 22, and a number of support segments 23, the support segments 23 and the second sealing segments 22 being arranged in an alternating successively abutting manner in the circumferential direction, and the first sealing segments 21 being arranged in a manner axially abutting the second sealing segments 22 and the support segments 23, and including a nose 24 extending axially on the second sealing segments 22, which is arranged in the circumferential direction between two adjacent first sealing segments 21.

Abstract: Conventional combinations of radially and tangentially cut packing rings require, in particular as wear progresses, a degree of resilient deformation of the resilient packing ring, in order to be able to achieve a satisfactory sealing effect. However, the level of wear achievable is limited thereby. On the other hand, sealing rings which offer a high level of wear and a long service life due to the cut arrangement wear in an uncontrolled manner, which is associated with a risk of damage to or destruction of the sealing rings, resulting in the need for regular maintenance and replacement of the sealing rings.

Abstract: Gastight piston ring arrangements require an active seal in the axial and radial directions in order to be able to obtain a high sealing effect. At the same time, the piston ring arrangement, while maintaining the sealing effect both on the sealing surface and between the parts of the piston ring arrangement, must be capable of readjustment in the event of continued wear. For a segmented piston ring comprising piston ring segments 2 having stepped ends 5, 6, this is achieved according to the invention by the fact that on at least one piston ring segment 2, on the radially inner peripheral surface 9 over a part of the width of the piston ring segment 2, a radial step 4 is provided, and a single-cut sealing ring 3 is provided, which bears radially against the inside of the peripheral surface 9 of the piston ring segments 2, and on the sealing ring 3 an axial recess 10, 12 is provided, which cooperates with the radial step 4 of the piston ring segment 2.

Abstract: In pressure packings for sealing a piston rod of a compressor, a combination of a radially cut and a tangentially cut packing ring is generally used. These two interacting packing rings must in this case be prevented from rotating relative to one another in order to ensure that the wear gaps are covered by the other ring in each case. The rotation prevention means is generally a pin which is placed in both rings. However, owing to the resulting differing wear to the radially cut and the tangentially cut packing ring, the rotation prevention pins are subjected to shear stress which can cause the pins to break. In order to avoid that, pressure packings are proposed which have individual packing rings and have to be specially cut for this purpose. The present invention describes a packing ring of this type that is distinguished by especially low wear to the ring segments and a long service life associated therewith.