Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C33/00—Moulds or cores; Details thereof or accessories therefor
  • B29C33/0055—Moulds or cores; Details thereof or accessories therefor with incorporated overflow cavities
• • A—HUMAN NECESSITIES
  • A63—SPORTS; GAMES; AMUSEMENTS
  • A63C—SKATES; SKIS; ROLLER SKATES; DESIGN OR LAYOUT OF COURTS, RINKS OR THE LIKE
  • A63C17/00—Roller skates; Skate-boards
  • A63C17/22—Wheels for roller skates
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C37/00—Component parts, details, accessories or auxiliary operations, not covered by group B29C33/00 or B29C35/00
  • B29C37/0078—Measures or configurations for obtaining anchoring effects in the contact areas between layers
  • B29C37/0082—Mechanical anchoring
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
  • B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
  • B29C41/04—Rotational or centrifugal casting, i.e. coating the inside of a mould by rotating the mould
  • B29C41/06—Rotational or centrifugal casting, i.e. coating the inside of a mould by rotating the mould about two or more axes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
  • B29C41/02—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles
  • B29C41/20—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of definite length, i.e. discrete articles incorporating preformed parts or layers, e.g. moulding inserts or for coating articles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/32—Wheels, pinions, pulleys, castors or rollers, Rims

Definitions

• This invention relates to a method to make skate rollers, to a mould to make skate rollers and to skate rollers manufactured according to such method and/or in such mould.
• Skate rollers made by injecting two-component plastic material into two half-moulds, in which a plastic radiate hub has been previously plugged, are known yet.
• rollers with a ring-shape tube plugged during the injection stage, putting in evidence an inner tube are known as well. However it is difficult to plug the tube in the correct position, which is the disadvantage of this kind of rollers.
• Fig. 1 shows a schematic longitudinal section of a mould to make skate rollers according to the invention.
• Fig. 2 shows double-rotation equipment of centrifu ⁇ gation
• Fig. 3 shows the longitudinal partial section of a roller produced according to the invention.
• the procedure in conformity with the invention implies the use of a mould generally indicated with 2 and made with a basic half- -mould 4, a ring-shape half-mould 6 and a locking plug 8 for the central opening of the ring-shape half-mould 6.
• the bottom of the basic half-mould 4 has a cylindric match 10 for the trueing up and the positioning of the hub 12 of the roller.
• this hub which is partially made of plastic material, there are appen ⁇ dixes 14, which form as a whole a ring-shape hollow 16, which has essentially a semicircular section. Furthermore these appendixes have loop-holes 17.
• the mould 2 To accomplish the roller according to the procedure the mould 2 must be taken from a furnace at about 100-120 'C and opened; the hub 12 must be put on the match 10, which is on the bottom of the basic half-mould 4.
• a ring-shape half-mould 6 must be put on the above-mentioned half-mould 4 and the polymeric material must be injected at a temperature of about 50°C into the ring-shape hollow 18, delimitated by the two half-moulds 4 and 6 and by the ring-shape hollow 16 of the hub.
• the quantity of injected material is not cor ⁇ responding to the volume of the ring-shape hollow 18, but it is a smaller one for the reasons further explained.
• This equipment 20 comprises a basic frame 22 that supports two horizontal co-axial shafts 24, one of which is activated by an electric engine 26. These shafts are linked in rotation to a further frame 28, which has two shafts 32 on its vertical rims 30. One of the two shafts is activated by an electric engine 34, which has a larger number of revolutions than that of the electric engine 26. These shafts 32 are linked in rotation to the mould 2.
• the contem ⁇ porary rotation of the mould 2 is caused both along the axis corresponding to the axis of the shafts 24 and along the axis corresponding to the axis of the shafts 32 with consequent centrifugation of the polymeric material put inside the hollow 18.
• the mould is put again into the furnace at 100-120°C till the complete poly ⁇ merization of the material.
• a fluorescent material can be used, in order to give a pleasant appearence to the roller during the use of the roller-skate.
• a different form of accomplishment could be that of pouring into the mould a quantity of polymeric material essentially corresponding to the volume of the ring-shape hollow 18. This procedure does not permit to make the inner tube or hollow 36, but it however presents the advantage of making possible the production of rollers without external bubbles.
• the aim of this innovation is that of accomplishing a procedure that makes possible the manufacturing of filled up skate rollers that are however without interior or external bubbles or hollows, in order to guarantee the best quality of the roller itself.
• Another aim of this procedure is that of permitting the greatest elasticity of the roller, even if it is filled up, injecting particular elasticizing elements as well as putting possible fins on the hub that must be covered.
• a further aim of this innovation is that of permitting the accomplishment of rollers with a particularly resistant exter ⁇ nal layer, with a possible tread and also with more elastic and more adherent to the prefabricated hub interior layers, which can be in different colours, in order to give to the roller also a new and original appearence.
• Another aim is that of making bindings inside the hub to assure the greatest road-holding quality of the covering.
• One more aim of the procedure is that of using the lateral surfaces of the roller to put any tread and also to put in low relief - or to carve - the trade mark or other fancy things.
• a method to accomplish skate rollers which is characterized in that in the stage of injec ⁇ tion of a plastic material, preferably a polymeric material, the mould is put in rotation on the axic cf the previously pressed hub, so that the injected material itself is centrifu ⁇ gated, the injectors being lowered and pushed towards the moulding hollow, placing itself uniformly in progressive layers till the complete filling up of the hollow itself.
• Fig. 4 of sheet 2 shows the axial section of the mould that makes possible the accomplishment of this procedure
• Fig. 5 of sheet 2 shows the plan and partially, the axial section of the previously pressed hub, on which the injection is applied, according to this procedure
• Fig. 6 of sheet 2 shows the same hub of fig. 2 seen from below,
• Fig. 7 of sheet 3 shows an axial section of the mould of fig. 4, into which the material has been injected, in order to accomplish the roller according to the innovation,
• Fig. 8 of sheet 3 shows the partially sectioned plan of a roller made with this procedure and Fig. 9 of sheet 3 shows the front of the roller of fig. 8 partially in axial section:
• the improved procedure according to this innovation implies the use of a mould 2 made from a basic half-mould 4, a ring- -shape half-mould 6 and a cone 7 for the locking of the hub 120.
• the cone has its fulcrum on the match 10 of the base 4.
• Pipes 9A-9B assure the injection of the two-component plastic material.
• this hub 120 has no ring-shape appendixes, but it is equipped with lightening holes 121 as well as possible fins 122, which are linked to a drum - or external surface 124 - and which preferentially have one or more variations in width 123, in order to offer the greatest adhesion surface of the plastic material to inject.
• the drum 124 itself is equipped with external incisions 125, which assure the largest supporting surface between the hub 120 itself and the material to inject.
• this improvement is thought to permit the accomplishment of a roller R, which is without the inner tube and which presents a body completely filled up by the injection, so that it is completely linked to the hub 120.
• the upper ring-shape mould 6 which is combined with the form of the moulding hollow 180 by a particular groove 181, which conveys the injected plastic material, and by a seat 182 on the half-mould 6 for the collection of the possible excess of plastic material.
• the surface of the moulding hollow 180 can be equipped with a carved 183 or in relief 184 and 185 stamp for the reproduction of the trade mark or writings - in relief R or in depth R - or also of the tread B on the resulting roller.
• this method implies the use of an equipment of centrifugation of the mould 2, based on only one movement instead of the two previously claimed, namely that on the axis of the hub 120. Consequently the frame of the equipment of centrifugation will be simpler than that already described, which remains however valid for the usable part.
• This rotation can be transmitted directly to the mould 2 with an adequate transmission of movement, or it can be applied to the cone 7, which, put under pression against the hub 120, gives the wanted speed of rotation to it and to the whole mould 2.
• the volume of the material to inject won't be lower than the volume of the housing hollow, since the accomplishment of the inner tube is not necessary anymore, but it must approxima ⁇ tely have the same - or a bit higher- value of the volume of the hollow 180.
• An injector 9A and/or 9B stokes the two-component plastic material, which has the same features already claimed in the patent to improve, and releases it into the groove 181 of the mould 2, while the mould 2 itself is put in rotation on the axis of the hub 120.
• the injectors 9A-9B are advantage ⁇ ously lowered below the groove 181.
• the centrifugal power transmitted to the mould 2 by its rotation dispatches the injected plastic material to the furthermost part of the hollow 180, placing itself in layers till the complete filling up of the hollow 180 itself.
• the centrifuged application of the plastic material guarantees the constant elimination of the air bubbles, which are gradually removed by the groove 181, assuring the good quality of the roller R in conformity to the main aim of this method.
• the roller R is finished with the perfect adhesion of the injected part on the drum 124, with its toothings 125 and its possible fins 122 of the hub 120, assuming a wrapping form of the external drum 124, which is particularly emphesized by the fig. 8.
• this method assures the possibility of getting an external surface of the roller R with a high resistence to the usage, while its central part can present greater features of elasticity and its central part - in contact with the fins 120 and the drum 124 - can present particular adhesiveness quali ⁇ ties, combining in a single roller R the best anti-usage, elasticity and adhesion to the hub 120 qualities.
• the continuous covering permits also to apply plastic material of different colours, in order to get rollers R with multiformity of colours, which is surely innovating.
• Fig. 11 of sheet 4 show, a further con ⁇ structional embodiment of the invention, as it has been mentioned.
• the attachment of the injected material to the hub 120 beyond that by fins 122 is secured by supplementary spaces 126 formed adjoining to the lightening holes 121.
• the hub 120 always has a hole passing through 129 and housing seats 128 for the conventional rolling means.
• the said spaces 126 are regularly filled with the plastic material according to the method of centrifugation already described for forming the connection of the brace-type and the incorporation of the lining R to the hub 120.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Casting Or Compression Moulding Of Plastics Or The Like (AREA)

Applications Claiming Priority (5)

Publications (1)

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Country Status (2)

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• 1996
  • 1996-11-18 EP EP96939068A patent/EP0861147A1/de not_active Withdrawn
  • 1996-11-18 WO PCT/EP1996/005041 patent/WO1997018937A1/en not_active Application Discontinuation

Non-Patent Citations (1)

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