Abstract: A multistage pump body comprises a first pumping chamber (20) and a second pumping chamber (21). A connecting duct (26a) puts an outlet (27) of the first pumping chamber (20) into communication with an inlet (28) of the second pumping chamber (21). A leak-tight conduit (40) is provided for the circulation of a cooling liquid. The connecting duct (26a) is a lateral duct of the multistage pump body. A heat-conducting wall (33) partially delimits the connecting duct (26a) and has an external surface (34) on the outside. At least a portion of the connecting duct (26a) passes between this external surface (34) of the heat-conducting wall (33) and the leak-tight conduit (40).

Abstract: The present invention concerns a dry vacuum pump comprising: a drive device (1) comprising a drive shaft (3) at one end of which is fixed at least one drive wheel (4) provided to set in motion at least one belt (5); at least two parallel rotors (7, 8) each having a shaft (9, 10) provided with a rotor element (11, 12), this shaft (9, 10) being able to be driven in rotation by the belt (5) and being equipped at one of its axial ends with a toothed wheel (13, 14), this pump having the special features that: the drive wheel (4) and the belt (5) are smooth; each shaft (9, 10) of the rotor (7, 8) comprises at least one smooth section (16, 17) arranged to co-operate with the belt (5), and the toothed wheels (13, 14) of the shafts (9, 10) of the rotor (7, 8) are dimensioned and arranged to mesh with one another.

Abstract: A dry pump for gases comprises a first rotor (1) comprising a first lobe portion (1A) and a first screw (1B), as well as a second rotor (2) comprising a second lobe portion (2A) and a second screw (2B). A casing delimits an internal volume in which are located together the first and second screws (1B, 2B) and the first and second lobe portions (1A, 2A). Each of the first and second screws (1B, 2B) comprises a threading invariable along its length. The first and second rotors (1, 2) turn in opposite directions and are located in successive configurations. In a first configuration of the rotors, the first and second lobe portions (1A, 2A), a portion of the first screw (1B), a portion of the second screw (2B) and the casing together delimit a chamber (30) which is closed. In a second configuration of the rotors, the chamber (30) has a smaller capacity than in the first configuration.

Abstract: A pumping method in a pumping system comprises: a main vacuum pump with a gas inlet port connected to a vacuum chamber and a gas outlet port leading into a conduit before coming out into the gas outlet of the pumping system, a non-return valve positioned in the conduit between the gas outlet port and the gas outlet, and an auxiliary vacuum pump connected in parallel to the non-return valve. The main vacuum pump is activated in order to pump the gases contained in the vacuum chamber through the gas outlet port, simultaneously the auxiliary vacuum pump is activated and continues to operate all the while that the main vacuum pump pumps the gases contained in the vacuum chamber and/or all the while that the main vacuum pump maintains a defined pressure in the vacuum chamber. Also included is a pumping system.

Abstract: A vacuum pump includes a casing having a first inlet orifice and a second outlet orifice to allow a flow of air, and in the interior of which a filtering element is mounted in a removable way. At least one orifice of the casing selected from among the first inlet orifice and the second outlet orifice is located on an exhaust lid. The exhaust lid is removable from the casing but integral with the filtering element. The connection between the casing and the exhaust lid is not tight. A cartridge for the vacuum pump includes an exhaust lid integrated in the closure nozzle of the filtering element. The connection between the casing and the exhaust lid is not tight.

Abstract: A pumping installation includes at least one first positive-displacement machine and one second positive-displacement machine, as well as a control module, in which installation a gas is evacuated from an enclosed volume by means of the first positive-displacement machine and/or the second positive-displacement machine. The pumping installation includes at least one control valve controlled by the control module and a pressure sensor for sensing the value of the pressure at the outlet of the first positive-displacement machine and/or a temperature sensor for sensing the value of the temperature at the outlet of the first positive-displacement machine in order to control the flow of gas between the enclosed volume and the outlet of the pumping installation.

Abstract: The present invention relates to a pumping system to generate a vacuum (SP), comprising a main vacuum pump which is a claw pump (3) having a gas suction inlet (2) connected to a vacuum chamber (1) and a gas discharge outlet (4) leading into a gas evacuation conduit (5) in the direction of a gas exhaust outlet (8) outside the pumping system. The pumping system comprises a non-return valve (6) positioned between the gas discharge outlet (4) and the gas exhaust outlet (8), and an auxiliary vacuum pump (7) connected in parallel to the non-return valve. In a pumping method by means of this pumping system (SP), the main vacuum pump (3) is started up in order to pump the gases contained in the vacuum chamber (1) and to discharge these gases through its gas discharge outlet (4), simultaneously to which the auxiliary vacuum pump (7) is started up.

Abstract: The present invention relates to a pumping method in a pumping system (SP, SPP) comprising: a main lubricated rotary vane vacuum pump (3) with a gas inlet port (2) connected to a vacuum chamber (1) and a gas outlet port (4) leading into a conduit (5) before coming out into the gas outlet (8) of the pumping system (SP, SPP), a non-return valve (6) positioned in the conduit (5) between the gas outlet port (4) and the gas outlet (8), and an auxiliary lubricated rotary vane vacuum pump (7) connected in parallel to the non-return valve (6).

Abstract: The present invention relates to a pumping method in a pumping system (SP) comprising: a primary dry screw-type vacuum pump (3) with a gas entry orifice (2) connected to a vacuum chamber (1) and a gas exit orifice (4) leading into a conduit (5) before coming out into the gas outlet (8) of the pumping system (SP), a non-return valve (6) positioned in the conduit (5) between the gas exit orifice (4) and the gas outlet (8), and an ejector (7) connected in parallel to the non-return valve (6).

Abstract: A vacuum pump includes a cylinder. The cylinder includes an inner casing forming two transversely intersected, parallel cylindrical chambers, the axes of which rest in one plane, and one of the faces of which represents a wall on which a suction hole inlet is located. The cylinder also includes an outer casing disposed around the inner casing to form a confined space, provided with the inlet and an outlet, which allows a liquid to be circulated. Two pump rotors are situated in the parallel cylindrical chambers and are driven in rotation by an electric motor. A drive housing contains the motor and components for driving and synchronizing the pump rotors supporting the rotors by cantilever and serving as support and centering with respect to the cylinder. The drive housing includes two extended supports that are integrally constructed as one piece.

Abstract: This application relates to a vacuum pump for applications in vacuum packaging machines, comprising: a cylinder, made up of the casing of two transversely intersected, parallel cylindrical chambers, the axes of which rest in one plane, and one of the faces of which represents a wall on which the suction hole is located, and the outer casing containing the casing of two parallel cylindrical chambers to form a confined space, provided with an inlet and an outlet, which allows a liquid to be circulated, carrying out the thermal exchange, and a drive housing containing the motor and the components for driving and synchronizing the pump rotors supporting said rotors by cantilever and serving as support and centring with respect to the cylinder.

Abstract: Device for extracting droplets of a liquid agent suspended in a gaseous fluid displaced in a machine for displacement of such a gaseous fluid, the extraction device comprising a first part and a second part. The first part comprising a first element, which is of elongated shape, with a longitudinal axis termed the first axis, and is intended to ensure a filtration function inside the apparatus; and a second element, which is intended to enable at least one of the following functions, which are a function of grasping at least by hand the first part and a function of fixing this first part to the second part. The second part comprising a wall that defines a chamber which is intended to be traversed by the gaseous fluid to be filtered and receives said first element in a position termed the operational position; and comprises an opening that delimits a passageway sufficient for the insertion of the first element into the chamber.

Abstract: The invention relates to a pump housing (2) comprising a dual-wall casing (3) which enables a first fluid (4) to flow at least partially around a compression chamber (5) for compressing a second fluid (6), said compression being performed with at least two elongated rotors (7, 8). The dual-wall casing (3) comprises: (i) a first wall (10) which defines the volume of the compression chamber (5), and (ii) a second wall (11) which extends around the first wall (10) at a distance (12) from same such as to enable the first fluid (4) to flow therethrough. The pump housing (2) consists of two subassemblies (13, 14), namely a first subassembly (13) and a second subassembly (14), which are assembled along a sealing surface (15) that is essentially orthogonal to the longitudinal axes (70, 80) of the rotors (7, 8).

Abstract: Device for extracting droplets of a liquid agent suspended in a gaseous fluid displaced in a machine for displacement of such a gaseous fluid, the extraction device comprising a first part and a second part. The first part comprising a first element, which is of elongated shape, with a longitudinal axis termed the first axis, and is intended to ensure a filtration function inside the apparatus; and a second element, which is intended to enable at least one of the following functions, which are a function of grasping at least by hand the first part and a function of fixing this first part to the second part. The second part comprising a wall that defines a chamber which is intended to be traversed by the gaseous fluid to be filtered and receives said first element in a position termed the operational position; and comprises an opening that delimits a passageway sufficient for the insertion of the first element into the chamber.

Abstract: Rotary displacement machine having a housing and at least two twinned rotors of asymmetrical profile, the twinned rotors each made of a core on which projects a helicoidal thread which extends above the core like a tooth. The helicoidal thread having a first predetermined dimension in a direction radial to the longitudinal axis of the twinned rotors and above the surface of a rotor. The machine having a first flank with a position and length of arc predetermined such that the shape of the first flank and the shape of the second flank each connect to one of the opposite ends of a connecting segment which constitutes a helicoidal surface. The connecting segment having a second predetermined dimension in a direction radial to the longitudinal axis of the twinned rotors such that the ratio of the second dimension over the first dimension ranges between 0.005 and 0.1.

Abstract: Rotary displacement machine comprising un housing and at least two twinned rotors referred to as being of asymmetrical profile, these twinned rotors each being made up of a core on which projects a helicoidal thread which extends above said core in the manner of a tooth which tooth has a first predetermined dimension in a direction radial to the longitudinal axis of that of the twinned rotors under consideration and above the surface of this rotor, this machine being characterized in that instead of comprising a first flank and a second flank of which the conventional shapes and connect at a first point in such a way as to form a sharp edge along the helicoidal thread: on the one hand, said first flank has a shape, referred to as modified shape, of which the position and the length of arc are predetermined such that said modified shape of this first flank and the conventional shape of the second flank each connect to one of the opposite ends and of a short segment, referred to as connecting segment, whic

Abstract: The twin screw rotors for axis-parallel installation in displacement machines for compressible media have asymmetrical transverse profiles and numbers of wraps that are ≧2. Depending upon the wrapping angle (&agr;), the pitch (L) varies, which pitch increases in a first subdivision (T1) from the suction-side screw end, reaches a maximal value (Lmax) after one wrap, decreases in a second subdivision (T2) until a minimal value (Lmin), and is constant in a third subdivision (T3). The pitch course in the first subdivision (T1) is preferably mirror-symmetrical to that in the second subdivision (T2), within the subdivisions T1 to T2, it is point-symmetrical to the mean values in almost all cases. Compact screw rotors, completely free of imbalance, can thereby be achieved with compression rates of 1.0 . . . 10.0, also without profile variation.