Abstract:
There is described a propeller (1 ) of the type comprising an external cylindrical casing (2) coupled directly or indirectly to an engine shaft in a manner rotatable about the axis (X) of the propeller, and at least one blade (3) provided with at least one fluid dynamic surface (4) constrained to a related blade shaft (5), which is in turn constrained to said external cylindrical casing (2) to be driven in rotation about the axis of the propeller. The blade shaft (5) has its axis (Y) which extends in a direction incident to the axis (X) of the propeller and the at least one fluid dynamic surface is driven by the related blade shaft in rotation about the axis of the propeller. The propeller is characterized in that the at least one fluid dynamic surface (4) is constrained in roto-translation to the related blade shaft (5), in a manner rotatable about, and translatable along, the axis (Y) of the blade shaft (5), in such a manner that the at least one fluid dynamic surface is translatable along the blade shaft, between an initial position and a final position, and the fluid dynamic surface rotates simultaneously from a first fluid dynamic pitch corresponding to said initial position to a second fluid dynamic pitch corresponding to said final position, and vice versa.
Abstract:
There is described a variable pitch boat propeller, comprising at least one internal cylindrical body and at least one blade pivoted to an external cylindrical body of the propeller constituted by one or more juxtaposed parts, and coaxial to the internal cylindrical body which is in turn fitted coaxially to a motor shaft and constrained thereto by means of a nut. The propeller also comprises retaining means, which cooperate with the internal cylindrical body of the propeller, to keep in assembled position, with interlocking, at least the internal cylindrical body, the external cylindrical body and the blades. The propeller is characterized in that it comprises means to constrain by coupling the nut, which allows the propeller to be constrained to the motor shaft, to the external cylindrical body of the propeller, or with at least a part thereof.
Abstract:
There is described, a variable pitch propeller comprising at least one blade pivoted rotatably to a cylindrical propeller casing (3), a propeller hub (4) coupled to a propulsor and positioned coaxially inside the propeller casing, a kinematic mechanism for adjusting the rotary motion of said at least one blade about its axis of pivoting to the propeller casing as a function of the relative motion of the propeller hub assembly with respect to the cylindrical casing thereof, and elastic means (8) for opposing relative rotation of the hub (4) with respect to the cylindrical propeller casing (3), and vice versa, comprising at least a first(9) and at least a second end(10)for operation thereof. The first end of the elastic means is constrained to the cylindrical propeller casing or to the hub, while the second end of the elastic means is constrained to at least one guide integral with the propeller hub or with the cylindrical casing, and the guide has at least a first and at least a second position for temporary operation of the elastic means which are mutually spaced apart.
Abstract:
There is described a variable pitch propeller comprising one or more blades pivoted to the cylindrical propeller casing (3), a propeller hub assembly (10, 11) coupled to a propulsor and positioned coaxially inside the propeller casing, a kinematic mechanism for adjusting the rotary motion of the blades about their axis of pivoting to the propeller casing as a function of the relative motion of the propeller hub assembly with respect to the cylindrical propeller casing, and means (12, 15, 30, 31) for coupling in rotation the propeller hub assembly to the propeller casing, comprising at least one elastic element (8) interposed between the hub assembly and the propeller casing. The coupling means have at least one inoperative position i.e. a position in which motion is not transmitted from the hub assembly to the propeller casing, in which, between the hub assembly and the propeller casing, at least a first angular space (alpha) is present for counter-clockwise rotation of the hub assembly with respect to the propeller casing, or vice versa, and at least a second angular space (beta) is present for clockwise rotation of the hub assembly with respect to the propeller casing, or vice versa.
Abstract:
A propeller and related method for the adjustment of the fluid-dynamic pitch of the propeller blades are described. The propeller is provided with at least one rotatable blade pivoted to a propeller cylindrical casing (3), a hub (2) adapted to be coupled to an engine and mounted within the propeller casing. The hub (2) is rotatable with respect to the propeller cylindrical casing (3), or vice versa, for at least one non-zero angular interval (a) for the adjustment of the fluid-dynamic blade pitch. Moreover, the hub comprises at least one contact surface (20, 21 ) movable between at least one direct or indirect disengagement position, and at least one direct or indirect engagement position with at least one respective abutment (10) which defines at least one limit stop of the angular interval (a). The limit stop abutment (10) comprises at least one region of at least one movable element (11 ) arranged in at least one seat (30) of the propeller cylindrical casing (3) for modifying the limit stop abutment position of the at least one angular interval (a). The propeller is characterized by comprising means (51, 52) to adjust the position of the at least one movable element (1 1 ), in one or more discrete intervals for the modification of the position of said at least one limit stop abutment (10) of the at least one angular interval (α).
Abstract:
There is described a1 variable pitch propeller comprising at least one blade pivoted rotatably to a cylindrical propeller casing (3), a drive shaft, coupled to a propulsor and positioned coaxially inside the propeller casing, a kinematic mechanism coupled to the drive shaft, or to the propeller casing, and to said blade, for adjusting the rotary motion of the blade or blades about its axis of pivoting to the propeller casing, and means for coupling in rotation the drive shaft to the propeller casing. The propeller is configured to provide at least one non-null angular range of relative rotation of the blade or blades about its axis of pivoting, with respect to the propeller casing, or vice versa. The means for coupling in rotation the drive shaft to the cylindrical propeller casing comprise at least one elastic element (8) interposed between the drive shaft and the cylindrical casing preferably acting at least when the propulsor drives in rotation the drive shaft according to at least one direction of rotation. The propeller also comprises at least one intermediate element (11) interposed between the drive shaft and the cylindrical propeller casing, provided with a first (20) and a second (21) contact surface with the drive shaft that are mutually spaced apart by an angular space for rotation of the drive shaft with respect to the intermediate element.
Abstract:
Variable - pitch propeller (1) of the type comprising at least one blade (6a, 6b, 6c) rotatably pivoted (20a, 20b, 20c) to a cylindrical casing of the propeller (3a, 3b, 4), a shaft coupled to an engine and coaxial to that propeller casing, a kinematic system (7, 8a, 8b, 8c, 10a, 10b, 10c, 11), coupled to the shaft, or to the propeller casing, and to above mentioned at least one blade, for regulating the rotary motion of said at least one blade around its own pivot axis to the propeller casing, as well as means (2, 14, 15) for transmitting the rotary motion of the shaft to the propeller casing, the propeller being shaped to provide at least one not null angular range for the free relative rotation of the above mentioned at least one blade (6a, 6b, 6c) around its pivot axis, relatively to the propeller casing (3a, 3b, 4). The propeller also comprises at least one elastic element (18, 18') countering the relative rotation of said at least one blade relatively to the propeller casing (3a, 3b, 4), or vice versa.
Abstract:
There are described an assembly comprising a plurality of screws (10) and a propeller and a related method for adjusting the fluid dynamic pitch of the blades of the propeller. The propeller is provided with at least one blade pivoted rotatably to a cylindrical propeller casing (3), a hub (2) coupled to an engine and mounted coaxially inside the propeller casing, a kinematic mechanism coupled to the hub and/or to the propeller casing, and to said at least one blade for adjusting the fluid dynamic pitch of the propeller by means of rotation of at least one blade about its pivot axis to the propeller casing. The hub (2) is rotatable with respect to the cylindrical propeller casing (3), or vice versa, for at least one non-zero angular interval (a) of operation of the kinematic mechanism for adjusting the fluid dynamic pitch, and the hub is also integral with at least one contact surface (20, 21) movable between at least one position of disengagement from and at least one position of engagement with, direct or indirect, at least one relative abutment (10, 40, 41) integral with the cylindrical propeller casing (3) which defines at least one limit stop of the angular interval (a). The assembly is characterized in that the plurality of screws (10) comprises at least two different screws and in that the propeller comprises at least one seat (30) for complete installation of at least one screw selected from the plurality of screws, and in that the at least one limit stop abutment comprises at least one region of at least one screw selected from the plurality of screws and installed in said seat provided in the propeller.
Abstract:
A device (1) for preventing and/or stopping rotation of a shaft (10) coupled to at least one motor, of the type comprising at least one first fixed element (2) with respect to this shaft (10), and at least one moving element (5), and means (3, 20, 21, 22, 30) to constrain said at least one moving element (5) to the shaft (10) in such a manner as to rotate integrally with this shaft (10) and at the same time be able to move between a position of friction contact with said least one fixed element (2), to allow stopping of the shaft (10), and a position of disengagement from this fixed element (2), to allow release of the shaft (10). The device advantageously provides that the means (3, 20, 21, 22, 30) to constrain said at least one moving element (5) to the shaft (10) comprise at least one link for movement of said at least one moving element (5) along a direction having at least a radial component with respect to the shaft (10).
Abstract:
There is described a propeller (1) of the type comprising an external cylindrical casing (2) coupled directly or indirectly to an engine shaft in a manner rotatable about the axis (X) of the propeller, and at least one blade (3) provided with at least one fluid dynamic surface (4) constrained to a related blade shaft (5), which is in turn constrained to said external cylindrical casing (2) to be driven in rotation about the axis of the propeller. The blade shaft (5) has its axis (Y) which extends in a direction incident to the axis (X) of the propeller and the at least one fluid dynamic surface is driven by the related blade shaft in rotation about the axis of the propeller. The propeller is characterized by comprising at least one guide constraint (11, 12) between the at least one fluid dynamic surface (4) and the respective blade shaft (5), said at least one guide constraint comprising at least one first section (11a) and at least one second section (11b). The at least one first section (11a) is shaped to allow the translation or the roto-translation of the fluid dynamic surface (4) relative to the blade shaft (5), and vice versa, and the at least one second section (11b) is shaped to allow the roto-translation of the fluid dynamic surface (4) relative to the blade shaft (5), and vice versa.