Abstract: An injection-molding method for manufacturing a sleeve (1) comprising a cylindroconical body comprising at least one deformable bellows portion (2) arranged in line with a base (3), by means of tooling comprising a mold (8) formed of at least two portions (81, 82) defining a mold cavity and a core that can be inserted into the mold cavity, and comprising a first cylindroconical portion (11) provided externally with a helical thread that is complementary to a helical thread of the mold (8) and a second portion (15) that is complementary to a recessed portion of the mold (8), said method comprises a step of filling the mold spaces left free between the core and the inside of the mold cavity (9), a step of opening the mold (8) during which, or at the end of which, the second portion (15) of the core is moved axially in a direction parallel to the winding axis (XX?) of the threads of the helical thread going away from the first portion (11) of the core, and a step of driving relative turning movement of the sleev

Abstract: An injection-molding method for manufacturing a sleeve (1) comprising a cylindroconical body comprising at least one deformable bellows portion (2) arranged in line with a base (3), by means of tooling comprising a mold (8) formed of at least two portions (81, 82) defining a mold cavity and a core that can be inserted into the mold cavity, and comprising a first cylindroconical portion (11) provided externally with a helical thread that is complementary to a helical thread of the mold (8) and a second portion (15) that is complementary to a recessed portion of the mold (8), said method comprises a step of filling the mold spaces left free between the core and the inside of the mold cavity (9), a step of opening the mold (8) during which, or at the end of which, the second portion (15) of the core is moved axially in a direction parallel to the winding axis (XX?) of the threads of the helical thread going away from the first portion (11) of the core, and a step of driving relative turning movement of the sleev

Abstract: A method for making a casing (1) with protective bellows (2, 2A) for transmission device, such as a transmission joint, includes at least two shafts mobile axially and/or at an angle relative to each other, the casing (1) with bellows (2, 2A), whereon at least part of the bellows (2?) are radial, having at each open end a section (3A, 3B) for being fixed to the transmission device. The method includes moulding the casing (1) with bellows (2, 2A), using a hollow mould and at least one core, having each at least a matching helical thread delimiting the moulding space and stripping the casing (1) formed by relatively unscrewing the casing (1) and the core to obtain a single-piece casing (1). The invention is applicable to a casing with bellows by arrangement of extensible or flexible coupling elements.

Abstract: The invention relates to a device for producing, by molding, a casing (3) having at least one helical bellows, comprising a mold (2) constituted of indentations and of at least one core (1) each having a helical threading complementary to one another whereby delimiting a molding space. Said device comprises means that make it possible to carry out an unscrewing relative to the casing (3) and to said core (1) in order to proceed with removing the casing from the mold. The invention is characterized in that it comprises means (51, 6) for holding each of the ends of the core (1) during molding, this core (1) having a helix angle of less than approximately 15°.

Abstract: A method for making a casing (1) with protective bellows (2, 2A) for transmission device, such as a transmission joint, includes at least two shafts mobile axially and/or at an angle relative to each other, the casing (1) with bellows (2, 2A), whereon at least part of the bellows (2?) are radial, having at each open end a section (3A, 3B) for being fixed to the transmission device. The method includes moulding the casing (1) with bellows (2, 2A), using a hollow mould and at least one core, having each at least a matching helical thread delimiting the moulding space and stripping the casing (1) formed by relatively unscrewing the casing (1) and the core to obtain a single-piece casing (1). The invention is applicable to a casing with bellows by arrangement of extensible or flexible coupling elements.

Abstract: Apparatus for blow-molding an article curved in three dimensions comprises two horizontally movable mold parts which, when in contact with each other, define a mold cavity curved in three dimensions to match the required article. An extrusion head extrudes a parison of synthetic resin material into the cavity so that it descends towards the lower end thereof. During this process, a first air flow is fed through apertures in a cover and passes through the mold cavity around the outside of the parison to ease the passage of the parison towards the lower end. In addition, a second air flow is fed through a nozzle in the extrusion head into the interior of the parison so as to help it descend and also to prevent its distortion as it moves into the mold cavity. Thereafter, closure members, which are slidable on, but movable independently of, the main mold parts, close off the upper and lower ends of the mold cavity and pinch the parison between them, their movements being controlled by respective actuators.

Abstract: A clamping ring, for clamping an end collar of a protective bellows to one end of a universal joint in a vehicle transmission, is made of resilient material having two overlapping end portions. One end portion has a tongue extending through a slot defined in the other end portion. In its relaxed state, the material of the ring holds the tongue in an initial position in the slot. When the ring is placed over the end collar of the bellows, the ring expands slightly to permit this, the tongue moving towards a "high" stop at one end of the slot. The ring then resiles slightly so as to hold itself on the bellows. When the bellows, with the ring in position, is placed over the end of the universal joint, the ring once more expands slightly to permit this. The ring is then tightened by moving the end portion until a hook engages a shoulder on the other end portion, the tongue moving towards a "low" stop at the other end of the slot.

Abstract: A protective bellows protects a universal joint driven by a shaft, such as forming part of the front wheel drive mechanism of a motor vehicle. The bellows has a collar with an interior annular rib which, on completion of the fitting process, locates in an annular groove in the shaft. During the fitting process, a tube is forced between the interior peripheral surface of the collar and the outer surface of the shaft, via a channel in the rib and a channel in the material of the inner end of the collar which grips the surface of the shaft. Grease is pumped into the interior of the bellows through this tube. Further channels extend through the rib and the adjacent material of the collar, and allow excess air Pressure to be vented to atmosphere during and after the grease-filling operation.

Abstract: An antivibration elastic support, particularly for the power plants of autovehicles. It essentially consists of an elastomer hollow unit (1), made to adhere to two rigid reinforcements (2)-(3) during vulcanization, the lower reinforcement (3) exhibiting an opening that can be stopped by an additional rigid reinforcement (4), the fluid-tight chamber (5), consisting of the walls of the hollow elastomer unit (1) and the reinforcements (2)-(4), being at least partially filled with a material that is easily deformable by outside application of energy, with absorption of the latter.