Abstract: A starting valve (100) for a fluid operating machine (200) for a vacuum system (1000). The starting valve (100) comprises:—a valve body (10) with an opening (17) to let a gas in; and an actuating piston (13) splined on a stem (16) free to slide in a guide (18A). The actuating piston (13), with a portion of the valve body (10), defines a chamber (30). The actuating piston (13) is subject to the action of a deformable diaphragm (15). A calibrated throttling hole (16B) is provided in series with a through hole (16A) in line with the stem (16) to establish a fluid communication between the chamber (30) and a fluid-dynamic line (500) of the vacuum system (1000). A shutter (20) is furthermore provided also splined on the stem (16). The shutter (20) closes a gas passage opening (10B) as a function of the pressure difference between the chamber (30) and the fluid-dynamic line (500).

Abstract: A starting valve (100) for a fluid operating machine (200) for a vacuum system (1000). The starting valve (100) comprises: a valve body (10) with an opening (17) to let a gas in; and an actuating piston (13) splined on a stem (16) free to slide in a guide (18A). The actuating piston (13), with a portion of the valve body (10), defines a chamber (30). The actuating piston (13) is subject to the action of a deformable diaphragm (15). A calibrated throttling hole (16B) is provided in series with a through hole (16A) in line with the stem (16) to establish a fluid communication between the chamber (30) and a fluid-dynamic line (500) of the vacuum system (1000). A shutter (20) is furthermore provided also splined on the stem (16). The shutter (20) closes a gas passage opening (10B) as a function of the pressure difference between the chamber (30) and the fluid-dynamic line (500).

Abstract: Screw compressor (1) comprising: a male (2) and a female rotor (3) rotating respectively around a first axis (01) and second axis (02) of rotation, said rotors (2;3) showing, in cross section, meshing lobes (4) and valleys (6) and having profiles generated by enveloping a rack profile (p) including a first curve (z1) of the rack profile (p) extending between a first point (H) and a second point (Q) in a Cartesian reference frame (X, Y) and having a convexity in the positive direction of the axis of abscissa (X), said first point (H) lying on the axis of abscissa (X) at a distance from an origin (0) of the Cartesian reference frame (X, Y) equal to an addendum (hi) of the male rotor (2).

Abstract: An embodiment of a dry screw compressor has a male rotor at a peripheral speed lower than approximately 80 m/s. The compressor includes: a casing body having an inlet for a gaseous fluid to be taken in and at least an outlet for the compressed fluid; at least a male rotor and at least a female rotor meshed together, said rotors being arranged inside said casing body whereby the ratio between the length and the external diameter of the male rotor is higher than or equal to approximately two, and the winding angle of the male rotor is smaller than or equal to approximately 300°.

Abstract: Screw compressor (1) comprising: a male (2) and a female rotor (3) rotating respectively around a first axis (01) and second axis (02) of rotation, said rotors (2;3) showing, in cross section, meshing lobes (4) and valleys (6) and having profiles generated by enveloping a rack profile (p) including a first curve (z1) of the rack profile (p) extending between a first point (H) and a second point (Q) in a Cartesian reference frame (X, Y) and having a convexity in the positive direction of the axis of abscissa (X), said first point (H) lying on the axis of abscissa (X) at a distance from an origin (0) of the Cartesian reference frame (X, Y) equal to an addendum (hi) of the male rotor (2).

Abstract: A gas rotary screw compressor (1), in particular, for cooling gas suitable for low-power systems, the compressor having a casing (1a) having an intake conduit (6) and a delivery conduit (7); and the casing (1a) having, internally, a three-dimensional region shaped to follow the outer profile of the helical teeth (11b) of a male rotor (11) and the helical teeth (12b) of a female rotor (12), so as to define a first intake chamber (45) to minimize the load losses of the gas stream and so fill the casing (1a) with a maximum quantity of gas.

Abstract: A method of chamfering and deburring the teeth of a gear having first teeth, each of the first teeth having a first and a second side and respective end faces; the method providing for meshing the gear with at least one tool having a ring gear meshing with the first teeth at edges formed between the first and second sides and the end faces; exerting compression between the first teeth of the gear and the ring gear; effecting a first permanent deformation of the edges to form first chamfer faces; and effecting at least a second permanent deformation between the first and second sides and the respective end faces; the first and the second permanent deformation being effected by means of enbloc tools having a first number of teeth and a second number of teeth.

Abstract: A gas rotary screw compressor (1), in particular, for cooling gas suitable for low-power systems, the compressor having a casing (1a) having an intake conduit (6) and a delivery conduit (7); and the casing (1a) having, internally, a three-dimensional region shaped to follow the outer profile of the helical teeth (11b) of a male rotor (11) and the helical teeth (12b) of a female rotor (12), so as to define a first intake chamber (45) to minimize the load losses of the gas stream and so fill the casing (1a) with a maximum quantity of gas.