CN1387989A

CN1387989A - Cyclic resin moulded goods

Info

Publication number: CN1387989A
Application number: CN 02120458
Authority: CN
Inventors: 广井清文; 若林康未
Original assignee: TAHES POLYMER CO Ltd
Current assignee: TAHES POLYMER CO Ltd
Priority date: 2001-05-24
Filing date: 2002-05-23
Publication date: 2003-01-01
Anticipated expiration: 2022-05-23
Also published as: JP3910022B2; JP2002347081A; CN1199777C

Abstract

To provide an annular resin molding improved in rigidity while keeping a good dimensional precision in which an insert member and a resin member are integrated by insert molding. A resin molding part is composed of a boss and a rim formed in the inner circumferential part of the web. The molding is injection-molded from a plurality of gates formed at equal intervals on a concentric circle on the surface of the web. The insert member in which a through hole is formed at a position facing the gates is embedded at least in the web. The resin molding part is formed integrally around the insert member.

Description

Cyclic resin moulded goods

Technical field

The present invention relates to insert the annular resin moulded work that is shaped and makes, especially adopt metal insert to improve the resin gears of rigidity, dimensional accuracy excellence.

Background technique

In recent years, engineering plastics are widely used as the metal substitute material, cyclic resin moulded goods such as the synthetic resin gear of its injection molded, pulley, the precision more and more strict to the roundness of its outer circumferential face, inner peripheral surface also require to improve the rigidity of the anti-mechanical force that is subjected in engagement transferring power such as pairing side gear or tooth bar the time.

Therefore, propose to insert the scheme that shaping is embedded in metal insert the cyclic resin moulded goods such as plastic gear of resin formation part, especially belly.And, in this moulded work, circumferentially continuous disc metal insert was configured in the metal forming mould in the past, melting resin is injected in the metal pattern to be solidified, the resin formation part that integrally formed metal insert and hub, belly, gear ring and tooth etc. are formed, because ester moulding shrinks along circumferential homogenization as far as possible, so can carry out injection molded from a plurality of injection holes injection resins that roughly equally spaced are provided with on the abdominal surface concentric circle.

; resin from the injection hole injection; on the metal insert surface to the belly of the single face of resin formation part; wheel hub; after the fillings such as gear ring; can spread to the back side of metal insert; the resin formation part of filling another side and being shaped; so there is resin flows inhomogeneous; become eccentric goods; and there is resin to inject and begins to finishing shaping needed time and resin flows apart from elongated; causing tooth portion is that main resin formation part filling is inhomogeneous and can not obtain the problem of good dimensional accuracy; and when the resin stream of resin formation part was narrow in the metal pattern, it is big that flow resistance becomes; formability worsens, and becomes moulded work precision forming serious hindrance.The purpose of this invention is to provide the moulded work keeping good dimensional accuracy, improve rigidity, make insertion parts and the incorporate cyclic resin moulded goods of resin component with the insertion forming method.

Detailed description of the invention

The cyclic resin moulded goods of the present invention that achieves the above object is the moulded work that possesses following scheme.

(1) the resin formation part wheel hub that perimembranous forms by belly, in belly and formed at the gear ring that the belly peripheral part forms, it is moulded work from a plurality of injection hole injection moldeds that on the concentric circle of abdominal surface, roughly uniformly-spaced are provided with, at least in aforementioned belly, be embedded in the insertion parts that through hole is offered at the position relative with aforementioned injection hole, around aforementioned insertion parts, form the aforementioned resin forming section.

(2) in the cyclic resin moulded goods of aforementioned (1), will form heavy section with the corresponding belly face of the radiation direction foreign side of the through hole of insertion parts.

(3) in the cyclic resin moulded goods of aforementioned (2), the insertion parts surface and the back side, the number that makes belly face heavy section with and/or shape inequality.

The cyclic resin moulded goods of aforementioned (1), because the resin that injects from injection hole is the resin passage of the through hole formation of the insertion parts by relative configuration with injection hole directly, and roughly on insertion parts table, the back side, flow and filling shaping resin forming section simultaneously, so can shorten the resin flows distance.As a result, except strengthening insertion parts and the resin formation part that forms around it integrated, resin does not have the time difference for the gear ring of forming section, the filling of wheel hub, and circumferentially approximate equality is carried out, and is shaped that it is even to shrink, and can keep the excellent size precision.The cyclic resin molded products of aforementioned (2), especially forming heavy section with the radiation direction foreign side of the openings of relative injection hole corresponding belly face, also promptly enlarged from the resin flow path of injection hole to the position of peripheral direction, resin is successfully flowed to the peripheral direction that has tooth portion, can carry out uniform resin fill more reliably.The cyclic resin molded products of aforementioned (3) changes in surface side and back side because of making aforementioned heavy section number, shape, so even two sides resin fill speed is different, also can adjust it, makes resin roughly flow to peripheral part simultaneously.

The simple declaration of accompanying drawing

Fig. 1 is the outward appearance plan view that cyclic resin moulded goods of the present invention is applied to an embodiment of external tooth gear.

Fig. 2 be among Fig. 1 X-X to sectional view.

Fig. 3 is the sketch of metal insert

Fig. 4 is the back side plan view of Fig. 1.

The working of an invention mode

As the mode of execution of cyclic resin molded products of the present invention, can enumerate external tooth gear, disc molded products.Below, with reference to the description of drawings embodiment of the invention.

The explanation cyclic resin moulded goods of the present invention that sees figures.1.and.2 is applied to an embodiment of external tooth gear, and Fig. 1 is its surface side plan view shape figure, and Fig. 2 is that its X-X is to sectional structure chart.

The synthetic resin gear 11 of present embodiment, as resin formation part, by not shown rotating shaft one be embedded in cylindrical shape wheel hub 12 in its axis hole, from wheel hub 12 peripheries along its attenuate that radially extends ring belly 13 and formed from the ring gear ring 14 that the periphery of belly 13 radially enlarges, be formed with the tooth portion 15 of regulation tooth pitch in gear ring 14 peripheries.And as insertion parts, endless metal inserted sheet 21 shown in Figure 3 is the inside that is inserted into belly 13 when the injection moulding of aforementioned resin forming section.

Aforementioned synthetic resin gear 11 is, when injection molding forming, inject in the die cavity of not shown injection mould, be that the melting resin of the radial diffusion in center forms, but also make resin be filled to the back side die cavity rapidly by a plurality of through holes 22 that are oppositely arranged with each injection hole 31 along the circumferential direct of metal insert 21 with each injection hole 31 by 6 injection holes 31 that from belly 13 surperficial concentric circles, roughly uniformly-spaced are provided with.Thereby, except in metal insert 21 surfaces, both sides, the back side, do not produce outside the difference from the time difference thermal process the same, the resin cooling of the resin arrival gear ring 14 outer peripheral teeth portions 15 that each injection hole 31 flows into, metal insert 21 also is firm with the integrated of resin formation part 12～15.

In addition, in the foregoing description, form roughly fan-shaped heavy section 16,16 ' from the openings 22 of metal insert 21 to the belly 13 corresponding, at this heavy section 16,16 ' with radiation direction foreign side, because resin passage is extended, so resin can be successfully to the filling of peripheral part direction.In the present embodiment, according to its back side plan view shape shown in Fig. 4, back side heavy section 16 ' shape, area diminish, and can adjust according to the resin flows situation.In addition, surface side and back side heavy section 16,16 ' number are increased and decreased adjusts.Be not limited to previous embodiment.Also can form the same number corresponding and same shape in table, back of the body two sides side with through hole 22, with the heavy section of wall thickness.

Illustrated embodiment more than has been described, but has the invention is not restricted to aforementioned embodiments, as cyclic resin moulded goods, except gear, also peripheral cam, pulley, worm screw etc., and gear is not limited to the horizontal gear mode, also umbrella gear, helical gear etc.

Adopt the present invention, even metal insert is embedded in the cyclic resin moulded goods in the belly wall thickness, then except can integrally formed securely insertion parts and resin component, can also control the resin flows at metal insert table, the back side reliably, be shaped shrinking can approximate equality, keep peripheral part dimensional accuracy and roundness well, the rigidity height, and can access high-precision cyclic resin moulded goods.

Claims

1. cyclic resin moulded goods, the resin formation part wheel hub that perimembranous forms by belly, in belly and form at the gear ring that the belly peripheral part forms, it is the moulded work of a plurality of injection hole injection mouldings of on the abdominal surface concentric circle, roughly uniformly-spaced being provided with, it is characterized in that, at least in described belly, be embedded in the insertion parts that through hole is offered at the position relative with described injection hole, around described insertion parts, form described resin formation part.

2. cyclic resin moulded goods as claimed in claim 1 is characterized in that, the belly face corresponding with the radiation direction foreign side of the through hole of insertion parts forms heavy section.

3. cyclic resin moulded goods as claimed in claim 2 is characterized in that, in insertion parts surface side and back side, makes the heavy section number and/or the shape of belly face inequality.