RU2205106C1 - Device and method for manufacture of ball bearing cage from fibrous materials - Google Patents

Abstract

FIELD: general engineering, particularly, manufacture of ball bearing cages applicable in vacuum, in media with low or high temperatures including chemically active media, or in media not allowing use of any lubricant, and, specifically, in manufacture of nonmetallic cages of ball bearings of gas-turbine high speed rotors. SUBSTANCE: device has attachment for blank winding, die, punch and shells. Attachment include cylindrical mandrel with pins and auxiliary cheeks with flanges in form of rectangular teeth secured to mandrel axle. Teeth are installed opposite to pins. Diameter and number of pins correspond to diameter and number of cage holes formed by them. Width of teeth corresponds to diameter of pins. Shells are made in form of sector of ring with conical external surface and split in axial direction across centers of holes drilled in ring in radial direction. Number and size of holes correspond to number and size of pins. Rind internal surface is cylindrical with diameter equaling cage outer diameter. Number of shells corresponds to number of pins. Method includes winding of fiber in definite directions, location of blank with installed shells in it into die and pressing. EFFECT: light-weight with prolonged service life ball bearing cages made of fibrous materials. 2 cl, 7 dwg

Description

 The invention relates to the field of general engineering, namely to the manufacture of ball bearing cages that can be used in vacuum, in environments with low or elevated temperatures, including chemically active, or environments that do not allow the use of any lubricant or lubricating oils, and in particular, to the manufacture of non-metallic ball bearing cages for high-speed rotors of gas turbine engines.

 The ball bearing cage serves to fix the working fluid in an annular direction. Currently used separators, as a rule, are metal, stamped with holes centered on the rolling elements. In bearings operating under conditions, for example, at higher speeds, separators are used from antifriction materials: bronze, brass, textolite, aluminum alloys. The use of traditional materials for the manufacture of the separator does not allow the creation of high-speed ceramic bearings, their use without lubrication in chemically active environments, at elevated temperatures - due to low strength, and at low temperatures - due to brittleness.

 The use of composite materials in the nodes of the supports of rotating parts, especially rotors of promising gas turbine engines, is relevant. Composite materials have unique characteristics that allow you to create workable designs where the use of metal materials for the manufacture of ball bearing cages is not possible.

 It is known "Device for the manufacture of annular products from fibrous materials", copyright certificate 1593964 dated 12/12/1988, with the help of which products from reinforced plastics obtained by winding are formed by pressing. The device comprises a mandrel with a preform wound thereon, a die and a punch having cone-shaped spacers installed between the preform and the die. The disadvantage of this technical solution is that in the manufacture of the separator requires additional mechanical processing associated with drilling holes for the working fluid of the bearing, which violates the integrity of the fibers and does not provide sufficient strength of the formed product.

 Known "Roller bearing", US 5271679, which can be used in vacuum, in an environment having high or low temperatures, or another medium that does not allow the use of any grease or lubricant, while the bearing cage is made by pressing using heat-resistant, composite, randomly reinforced material with self-lubricating properties. The disadvantage of the proposed technical solution is the fragility and low strength of the separator at high speed loads.

 The technical result is the creation of lightweight, with increased durability of non-metallic ball bearing cages made of fibrous materials.

 The technical result is achieved by the fact that alternating winding of layers of fibrous materials is created on the forming tooling in certain directions of the reinforcing layers, using heat-resistant binders and with the addition of antifriction materials. The resulting workpiece with conical inserts inserted into it, which, when pressed, self-center and self-install, is placed in the mold. Pressing is carried out by a matrix, upper and lower punches, the forming surfaces of which coincide with the dimensions of the manufactured separator. The pressing process is carried out in a given mode. The result is a finished product completely "in size", without further mechanical processing, with high characteristics of rigidity and strength.

 Figure 1 and figure 2 shows a diagram of the forming technological equipment for winding the separator.

 Figure 3 shows a diagram of a mold for forming a separator.

 Figure 4 shows a method of laying fiber onto a snap.

 Figure 5 shows a top view of a conical ring.

 Figure 6 shows a sectional view of a conical ring.

 Figure 7 shows a view of a liner made of a conical ring.

 A device for manufacturing a ball bearing cage of fibrous materials in figure 1 and figure 2 contains snap-in for separator winding, consisting of a cylindrical mandrel 1 with pins 2 mounted on it, the number and diameter of which correspond to the number and diameter of the holes of the manufactured separator formed by them 9. On the axis 3 of the cylindrical mandrel 1 set the right technological cheek 4 and the left technological cheek 5, which are fixed with a nut 7 and washer 8. The technological cheeks 4 and 5 have rectangular flanges teeth 6, the width of which corresponds to the diameter of the pins 2. The rectangular teeth 6 are oriented so that they are installed opposite the pins 2. The grooves of the technological cheeks 4 and 5 and the pins 2 are guiding elements for the transverse winding of the separator with carbon fiber. Rectangular teeth 6 of technological cheeks 4 and 5 are width limiters when winding the annular layers on the snap. The device for manufacturing a ball bearing cage of fibrous materials in FIG. 3 contains a mold for forming a cage 9, consisting of an upper punch 11, a lower punch 12 and a matrix 13. After winding the carbon fiber on the snap between the pins 2 of the cylindrical mandrel 1, insert 10. 7 shows a liner 10 having the shape of a ring sector, the view of which is shown in FIG. 5 from above, and FIG. 6 is a sectional view, with a conical outer surface, axially cut through the centers of the holes drilled in ring in the radial direction, while the number and size of the drilled holes correspond to the number and size of the pins 2 snap-in for winding the separator 9. The inner surface of the ring is cylindrical, with a diameter equal to the outer diameter of the manufactured separator 9, and the number of inserts 10 corresponds to the number of pins 2 installed on a cylindrical mandrel 1.

 Figure 4 shows a method of laying carbon fiber on a snap, which consists in the alternation of layers having certain directions of reinforcement.

The method of winding carbon fiber snap is as follows:
- the fibers forming the separator holes are wound directly around each pin 2 to its height, figa;
- the fibers forming the side walls of the separator are wound in the annular direction of the snap between the rectangular teeth 6 and the pins 2, figb;
- the fibers forming the jumpers between the separator holes are wound between the pins 2 and the rectangular teeth 6 of the technological cheeks 4 and 5 in the axial direction, figv;
- the fibers connecting the separator walls and jumpers between the separator holes are wound in an annular direction, enveloping each pin 2 and remaining inside the space bounded by technological cheeks 4 and 5, Fig. 4d;
- the fibers connecting the walls and jumpers of the separator are wound in an annular direction, bending around the pins 2 and going outside the rectangular teeth 6 of the technological cheeks 4 and 5, first from left to right, then in the opposite direction, filling the space between the pins 2 and rectangular teeth 6 Fig. 4d.

 After the carbon fiber is completely filled with equipment, the transverse fibers and fibers extending beyond the rectangular teeth 6 of the technological cheeks 4 and 5 are cut off from the outside of the rectangular teeth 6, after which the technological cheeks 4 and 5 are laid out and removed, and the inserts 10 are laid between the pins 2, In this case, the liners 10 with their inner surface touch the upper wound layers of the separator, and the outer - conical, slide along the response cone of the matrix 13. The assembled snap-in is placed in the matrix 13 and squeezed on both sides by the upper 11 and lower 12 punches. The assembled mold is placed under the press and the product is pressed according to the specified technological and temperature parameters.

 The thickness of the separator after winding is provided by the specified height of the technological cheeks. The winding and tension control of carbon fiber is carried out automatically. The pressing winding allowance is 1 mm.

 The proposed device and method for the manufacture of a ball bearing cage made of fibrous materials can ensure the durability, strength and stiffness of cages made of composite materials using heat-resistant binders and with antifriction additives, which increases the durability of high-speed bearing units during long-term operation in various environments and use them without lubrication .

Claims (2)

 1. A device for the manufacture of a ball bearing cage of fibrous materials, containing snap-in for winding the workpiece, a matrix, a punch and inserts, characterized in that the snap-in consists of a cylindrical mandrel with pins installed on it, the diameter and number of which correspond to the diameter and number of separator holes formed by them , and from technological cheeks fixed on the mandrel axis with flanges in the form of rectangular teeth mounted opposite the pins, the tooth width corresponding to the diameter of the pins, and the liners are made in the form of a sector of the ring with a conical outer surface, cut in the axial direction at the centers of the holes drilled in the ring in the radial direction, and the number and size of the drilled holes correspond to the number and size of the snap pins, while the inner surface of the ring is cylindrical with a diameter, equal to the outer diameter of the manufactured separator, and the number of inserts corresponds to the number of pins on the snap.  2. A method of manufacturing a ball-bearing cage made of fibrous materials, which consists in winding the fiber for tooling and molding the obtained workpiece by pressing, characterized in that the tool is wound in the following directions of reinforcement: first, the fibers are wound around each pin to its height, then they are wound in a ring the direction of the snap between the rectangular teeth and pins, after which the winding is carried out between the rectangular teeth and pins in the axial direction, then the fibers are wound in a ring in the direction of rotation around each pin of the snap, remaining inside the space bounded by the technological cheeks, and then the fibers are wound in an annular direction, bending around the pins and going outside the rectangular teeth of the technological cheeks, first from left to right, then in the opposite direction, filling the space between the pins and rectangular teeth, and after winding the workpiece, transverse fibers and fibers extending beyond the rectangular teeth are cut from the outside of the teeth, the technological cheeks are laid out and removed, s laying the inserts between the pins, snap-assembled are placed in a die and punch are pressed.

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