摘要:
A method for controlling the deformation of a surface of a sail of a sailing boat during a direction change maneuver, includes arranging at least one inflatable batten into a respective seat formed on a side surface of the sail, the at least one batten being inflated at a predetermined working pressure as to impart to said at least one inflatable batten a bending stiffness having, with no bending load, a predetermined value, carrying out a maneuver for changing the direction of the sailing boat, wherein in a first part of maneuver, the at least one batten is subjected to the action of an increasing bending load, and in a second part of the maneuver, the bending load ends its action on the at least one batten, during the maneuver the mechanical properties of the at least one batten being changed so that as the bending load increases in the first part of the maneuver, the value of the bending stiffness of the at least one batten decreases considerably, and as the action of the bending load ends in the second part of the maneuver, the bending stiffness of the at least one batten returns to the predetermined value.
摘要:
There is described a method for controlling the deformation of a surface of a sail (1) of a sailing boat (100) during a direction change manoeuvre, said method comprising the step of arranging at least one inflatable batten (10) into a respective seat (3) formed on a side surface (2a) of the sail (1), said at least one batten (10) being inflated at a predetermined working pressure, said working pressure being such as to impart to said at least one batten (10) a bending stiffness having, with no bending load, a predetermined value and the step of carrying out a manoeuvre for changing the direction of the sailing boat (100), wherein in a first part of said manoeuvre said at least one batten (10) is subjected to the action of an increasing bending load and in a second part of said manoeuvre, said bending load ends its action on said at least one batten (10), during said manoeuvre the mechanical properties of said at least one batten (10) being changed so that as said bending load increases in said first part of the manoeuvre, the value of the bending stiffness of said at least one batten (10) decreases considerably, and as the action of said bending load ends in said second part of the manoeuvre, the bending stiffness of said at least one batten (10) returns to said predetermined value. Such method is carried out by using a sail (1) provided with at least one batten (10) comprising a fluid impervious wrapping (31) adapted to be inflated by a fluid under pressure and a reinforcing structure (33) associated externally with said wrapping (31) and comprising a plurality of reinforcing thread-like elements (34a, 34b) arranged crossed with an angle comprised between about 65° and about 115°.
摘要:
A method for controlling the deformation of a surface of a sail of a sailing boat during a direction change manoeuvre, includes arranging at least one inflatable batten into a respective seat formed on a side surface of the sail, the at least one batten being inflated at a predetermined working pressure as to impart to said at least one inflatable batten a bending stiffness having, with no bending load, a predetermined value, carrying out a manoeuvre, for changing the direction of the sailing boat, wherein in a first part of manoeuvre the at least one batten is subjected to the action of an increasing bending load, and in a second part of the manoeuvre, the bending load ends its action on the at least one batten, during the manoeuvre the mechanical properties of the at least one batten being changed so that as the bending load increases in the first part of the manoeuvre, the value of the bending stiffness of the at least one batten decreases considerably, and as the action of the bending load ends in the second part of the manoeuvre, the bending stiffness of the at least one batten returns to the predetermined value.
摘要:
A wheel having a controlled pressure includes a rim associated with a tank adapted to be filled with a fluid to a first pressure; a tire mounted on the rim and having an inner volume inflated to an operating pressure at a reference temperature, the operating pressure being lower than the first pressure; and at least one valve assembly adapted to establish a communication between the tank, the inner volume of the tire and the external environment. The valve assembly includes a command valve, an exhaust valve and a compensation valve operatively associated with each other. The command valve controls communication between the tank and the inner volume of the tire. The exhaust valve is connected to the external environment, to the inner volume, to the command valve and to the compensation valve. The compensation valve is connected to the exhaust valve and the command valve. The command valve includes an inner chamber connected with the exhaust valve and the compensation valve in such a manner that the command valve is operated by the exhaust valve and the compensation valve through a pressure variation of the inner chamber in response to a variation of the inner pressure of the tire.
摘要:
A wheel having a controlled pressure includes a rim associated with a tank adapted to be filled with a fluid to a first pressure; a tyre mounted on the rim and having an inner volume inflated to an operating pressure at a reference temperature, the operating pressure being lower than the first pressure; and at least one valve assembly adapted to establish a communication between the tank, the inner volume of the tyre and the external environment. The valve assembly includes a command valve, an exhaust valve and a compensation valve operatively associated with each other. The command valve controls communication between the tank and the inner volume of the tyre. The exhaust valve is connected to the external environment, to the inner volume, to the command valve and to the compensation valve. The compensation valve is connected to the exhaust valve and the command valve. The command valve includes an inner chamber connected with the exhaust valve and the compensation valve in such a manner that the command valve is operated by the exhaust valve and the compensation valve through a pressure variation of the inner chamber in response to a variation of the inner pressure of the tyre.
摘要:
A wheel having a controlled and compensated pressure includes a rim associated with a tank adapted to be filled with a fluid to a first pressure; a tyre mounted on the rim and having an inner volume inflated to an operating pressure, the operating pressure being lower than the first pressure; at least one valve adapted to regulate a communication between the tank and the inner volume of the tyre, the valve having at least one elastic element operatively associated with a closure member designed to open and close a port of the valve to bring the tank into communication with the tyre when the pressure of the tyre is lower than the operating pressure, the elastic element having an elastic constant showing a variation of 10% to 40% within a temperature range of about −50° C. to about 50° C.
摘要:
A method for controlling a phase of molding an annular fixing structure of a green tire includes: introducing the green tire into a curing mold including an inflatable bladder; delimiting at least one portion of the annular fixing structure by using a first and a second surface opposed to each other; bringing the first surface and the second surface so as to bring a portion of the first surface and a portion of the second surface into contact with a corresponding radially inner and axially inner surface portion and a corresponding radially inner and axially outer surface portion, respectively, the annular fixing structure generating a first squeezing pressure; inflating the inflatable bladder of the curing mould so as to bring the first and the second surfaces closer together, thus generating a second squeezing pressure in such a way as to shape the radially inner and axially inner surface portions and the radially inner and axially outer surface portions of the annular fixing structure.
摘要:
In a process of manufacturing pneumatic tires, a carcass sleeve is made which includes at least one carcass ply provided with axially opposite flaps turned up around annular anchoring structures, so as to form respective loops. An outer sleeve is positioned around the carcass sleeve and the latter is radially expanded in order to cause application of same against a radially internal surface of the outer sleeve. After each of the end flaps has been turned up and before radial expansion, only a portion belonging to each of the loops and extending substantially parallel to the respective annular anchoring structure is submitted to a step of carrying out heating under pressure, to make each loop integral with the annular anchoring structure and prevent the turned-up ply/plies from even partly slipping off, during the subsequent radial-expansion step of the carcass sleeve and vulcanization step of the tire.
摘要:
Equipment for molding and curing a green tire includes a curing mold including a first bead molding ring including a first surface for contacting a radially inner and axially inner surface portion of an annular fixing structure of the green tyre and a first sidewall plate including a second surface for contacting a radially inner and axially outer surface portion of the annular fixing structure. The first bead molding ring is radially extendable from a contracted operating position to an expanded operating position so as to delimit a portion of the annular fixing structure between the first sidewall plate and the first bead molding ring, and the first bead molding ring is translatable towards the first sidewall plate for generating a first squeezing pressure on the annular fixing structure. The equipment further includes an inflatable bladder associated for operation with the curing mold.
摘要:
A process for moulding and curing tyres, includes introducing a green tyre into a curing mould, the mould including a first sidewall plate and a second sidewall plate, a ring of circumferential sectors circumscribing a mould cavity, an expandable bladder delimited by a membrane, and at least one bead moulding ring which is movable between a first contracted operating position and a second extended operating position; and moulding and curing the green tyre in the curing mould; and between introducing the green tyre and moulding and curing it, the process includes extending the at least one bead moulding ring from the first contracted operating position to the second extended operating position; forming a circumferential bearing surface which bears against a first axially inner surface portion of a first annular fixing structure of the green tyre; pressing a second axially inner surface portion of the first annular fixing structure by expanding the membrane at a pre-moulding pressure which is lower than a moulding pressure, so as to bring the first annular fixing structure into contact with the first sidewall plate thus shaping an axially outer surface portion of the first annular fixing structure by means of the first sidewall plate and shaping the first axially inner surface portion of the first annular fixing structure by means of the circumferential surface of the at least one bead moulding ring.