Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16G—BELTS, CABLES, OR ROPES, PREDOMINANTLY USED FOR DRIVING PURPOSES; CHAINS; FITTINGS PREDOMINANTLY USED THEREFOR
  • F16G5/00—V-belts, i.e. belts of tapered cross-section
  • F16G5/16—V-belts, i.e. belts of tapered cross-section consisting of several parts

Definitions

• the present invention relates to a friction transmission belt.
• tra ⁇ pezoidal transmission belts more efficient than conventional textile belts, intended to be fitted with pulley variators each consisting of two smooth conical discs. The approximation and spacing of these discs produces the change of transmission ratio.
• pulley variators each consisting of two smooth conical discs.
• the approximation and spacing of these discs produces the change of transmission ratio.
• armature made up of overlapping strips.
• This principle is taken up in several patents with improvements in details, in particular in the German patents 2505228 and American patent 3949621.
• the major drawback of this system lies in the great difficulty of producing the armature. composed of about 10 metal strips, without welding, concentrically nested one inside the other, with a very low tolerance. This results in an excessive return price which makes marketing difficult.
• This belt EE longitudinal longitudinal.
• the components of this belt are metallic or some other resistant material. These components are linked together by an injection of elastomer, adhered to each of the parts, which secures all the elements together.
• This belt is the subject of French patent 7907340.
• the belt according to the invention provides a simple solution for manufacturing and mounting to achieve the same goal, which is to transmit a large force, with continuous variation of the speed in a small footprint.
• the belt according to the invention consists of an endless ribbon, comprising reliefs, made of a material sufficiently resistant to withstand the forces transmitted by attached parts, and flexible enough to be wound according to the minimum diameter of the pulleys, for example a polyamide, a polyurethane, etc.
• This ribbon is provided longitudinally with a mature ar ⁇ sufficiently solid to take up the traction forces of the transmission, and flexible enough to wind up according to the minimum diameter of the pulleys; it consists, for example, of a winding of cabled or non-cabled metal or metalloid fibers, a braid of metal or metalloid fibers woven in the form of a tube to avoid a connection, or else woven in thin ribbon and wound with several towers superimposed in the form of a spiral ...
• the reliefs of the ribbon serve as stops: between two successive stops, plates of generally trapezoidal shape take their place. These plates take up in the grooves of the pulleys, they ensure the friction transmission between the ribbon and the grooves of the pulleys.
• These plates are made of a material hard enough to withstand the pressure and friction forces, for example treated steel, sintered metal, metalloid having qualities of sufficient hardness. The invention will be better understood using the
• FIG. 1 represents an elevation view of a portion of the endless belt, with segments 5 successively representing the armature alone, the armature coated with a semi-rigid material constituting the ribbon and the ribbon equipped with plates.
• FIG. 2 represents a cross-sectional view along II-II of FIG. 1.
• FIG. 3 represents a cross-sectional view along III-III of FIG. 1.
• FIG. 5 is an elevation view of the endless line representing an alternative embodiment of the plates
• FIG. 6 represents a view in transverse section practiced at the level of the ribbon showing a variant embodiment of the plates.
• the transmission belt according to the present in ⁇ vention consists of a frame 1 coated with a semi-rigid material 7, for example a polyamide. This set constitutes the ribbon.
• the polyamide alternately comprises flat rectangular sections 2, barely thicker than the reinforcement 1, and sections 3, three to five times thicker than the sections 2. Between two successive sections 3 is housed a friction pad 4 which can
• O PI for example be of treated steel.
• the armature 1 can be constituted by a winding, in the surface of the neutral fiber of the belt, of cabled or non-cabled fibers, of metal or of metal-lo ⁇ de. It can also consist of an endless braid woven in tubular form so as not to have a connection (a connection is always a cause of premature rupture). Finally, this frame can be constituted by a very thin ribbon, as wide as the frame, and wound several times on itself in the form of a spiral. In all these cases the armature will have a thickness of the order of a millimeter.
• the frame 1 constituted either by cables, or by a braid or the like, has openings representing approximately 30% of its surface. These openings are intended to allow the passage of the polyamide during injection, so that the frame 1 and the polyamide are intimately mixed. These openings are obtained in the case of a cable, by leaving a space during the winding side by side of the successive turns, and, in the case of a braid, by providing sufficient days between the meshes during the weaving, or by practicing them by spacing the fibers after weaving.
• Polyamide 7 or the like enters the frame 1 and coats it.
• the ribbon has a thickness greater by a few tenths of a millimeter than that of the reinforcement 1.
• the width of the ribbon is greater than that of the reinforcement 1 of the order of a few millimeters.
• the height of the sections 3 is approximately three to five times greater than that of the sections 2, their width may be identical to that of the sections 2 (fig. 2 and 3), for reasons of simplification of the making of the mold. polyamide or the like.
• Their width can also be greater than that of sections 2 (fig. 4) and extend along 3a and 3b of
• Sections 3 protrude above and below sections 2 by a substantially equal height.
• the top shape 3c has its sides perpendicular to the frame, while the bottom shape 3d has its sides which move towards the bottom to allow the strap to follow the minimum rolling radius necessary for its operation, without the lower parts 3d of the sections 3 coming to tighten excessively on the plates 4.
• the thickness of the sections 3 measured in the direction of travel of the line is substantially identical to the space between two successive sections 3.
• the frame 1 arrives flush, or even protrudes slightly under the polyamide at the level of sections 2, for known needs for positioning the frame at the time of molding.
• This arrangement can be favorable in the case of the armature 1 constituted by cables or by a metal braid, there is then direct contact with the armature with the level 4a of the plates 4 and good transmission of the pressure effort there.
• the reinforcement 1 is made up of metalloid fibers
• this contact may be the cause of rapid wear of the fibers. It is then advisable either to reduce as much as possible when making the mold, the positioning line, or to turn the belt after molding and before mounting the pads 4. In this turning operation the top becomes the below and vice versa. This reversal is only possible without introducing significant constraints due to the thinness of the ribbon. It goes without saying that the shape details of the mold will be slightly different depending on whether the belt is to be turned over or not. The advantage of flipping is
• the surface condition of the level 4a of the plates 4 must be good to avoid rapid wear of the tape and of the frame at this location.
• the plates 4 which are all similar to each other (FIG. 3) are planar, and have a uniform thickness equal to the space comprised between two successive sections 3. Viewed according to Figure 3 they have a general trapezoidal shape.
• the non-parallel faces 4b and 4c of the trapezoid form between them an angle of approximately 20 °. These faces are intended to rest in the grooves of the pulleys. It is through these faces 4b and 4c that the friction drive takes place.
• the plates 4 are provided with a notch 4d parallel to the bases and situated substantially halfway up the trapezoid. The height of this notch 4d is equal to the thickness of section 2 of the ribbon.
• the plate 4 is intended to be introduced on a section 2 (between two sections 3), by one side of the ribbon, the length of the notch 4d is such that the plate 4 can reach, once introduced on the ribbon, a position in which it protrudes symmetrically on each side of this ribbon.
• the plates 4 are mounted alternately on one side and then on the other side of the ribbon.
• a set of wafers composed of two wafers 5 as shown in FIG. 5 can be substituted.
• the general shape of the wafers 5 is identical to that of the wafers 4, apart from the differences which will be described below:
• the plates 5, all similar to each other, have a thickness equal to half that of the plates 4, they are slightly folded parallel to the bars.
• O PI its trapezoid, at the neutral fiber of the cour ⁇ roie. They are mounted two by two on each section 2, a plate 5 being introduced by one of the sides of the ribbon and the other plate 5 by the other side. Thus placed face to face, the fold of each of them tends to spread the two small bases 5a from one another, on a stretched portion of the belt, while the two small bases 5a touch for the minimum radius of winding of the belt.
• a first advantage of this variant is that the plate 5 carries permanently over the entire surface on the side of the section 3, which results in a better distribution of the pressure forces of the plate 5 on the side of the section 3.
• a second advantage is the doubling of the contact lines on the pulleys.
• a belt equipped with plates 5 has twice the number of plates, and contact lines, that a cour ⁇ line identical otherwise, but equipped with plates 4. Whether it is plates 4 or 5, these are prevented from leaving the belt by the presence of a 4th swelling near the entrance to the notch 4d which has the effect of slightly reducing the width of the notch at this location. It is therefore necessary to force to insert the plates on sections 2.
• a second variant of the plate 4 consists in providing a symmetrical opening 6d in the upper part of the plate (FIG. 6), in place of the notch 4d described for the plate 4.
• the plate 6 thus formed is inserted on the belt from below
• the variant consisting of slightly folded half-thickness plates can also be applied to plates 6 with the same advantages as those previously described.
• the belt, object of the invention designed to work dry or in an oil bath can be used wherever a variable ratio transmission is necessary, in industry as in the automobile. It is intended to equip variators with pulleys with trapezoidal grooves.
• This belt finds a particularly interesting application in the equipment of variators which, due to the reduction in their size, can be advantageously mounted on motor vehicles.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Pulleys (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=9263490

Family Applications (1)

Country Status (5)

Cited By (2)

Families Citing this family (2)

Citations (9)

• 1981
  • 1981-10-28 FR FR8120246A patent/FR2515296B1/fr not_active Expired
• 1982
  • 1982-10-25 WO PCT/FR1982/000172 patent/WO1983001665A1/en unknown
  • 1982-10-25 ZA ZA827773A patent/ZA827773B/xx unknown
  • 1982-10-27 IT IT23949/82A patent/IT1155409B/it active
  • 1982-10-27 ES ES516897A patent/ES516897A0/es active Granted

Patent Citations (9)

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