JP4860650B2 - Synthetic resin molded product - Google Patents

Synthetic resin molded product Download PDF

Info

Publication number
JP4860650B2
JP4860650B2 JP2008052767A JP2008052767A JP4860650B2 JP 4860650 B2 JP4860650 B2 JP 4860650B2 JP 2008052767 A JP2008052767 A JP 2008052767A JP 2008052767 A JP2008052767 A JP 2008052767A JP 4860650 B2 JP4860650 B2 JP 4860650B2
Authority
JP
Japan
Prior art keywords
boss
synthetic resin
molded product
deformed portion
ribs
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP2008052767A
Other languages
Japanese (ja)
Other versions
JP2009210005A (en
Inventor
真史 塩崎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tigers Polymer Corp
Original Assignee
Tigers Polymer Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tigers Polymer Corp filed Critical Tigers Polymer Corp
Priority to JP2008052767A priority Critical patent/JP4860650B2/en
Publication of JP2009210005A publication Critical patent/JP2009210005A/en
Application granted granted Critical
Publication of JP4860650B2 publication Critical patent/JP4860650B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Moulds For Moulding Plastics Or The Like (AREA)
  • Gears, Cams (AREA)

Description

本発明はＯＡ機器などに使用される合成樹脂歯車やプーリーなどの合成樹脂成形品に関する。特に成形品の中心軸部にキー溝などの異形部分を有する合成樹脂成形品に関する。 The present invention relates to a synthetic resin molded article such as a synthetic resin gear or a pulley used for OA equipment. In particular, the present invention relates to a synthetic resin molded product having a deformed portion such as a keyway at the central shaft portion of the molded product.

近年、金属代替品として汎用されているエンジニアリングプラスチックにより射出成形されるプラスチック歯車、プーリー等の円盤状合成樹脂成形品は、外周面や内周面の真円度や振れに厳しい精度が要求されている。このような略円状の外周形状を有するプラスチック成形品を高精度で射出成形するためには、通常複数のゲートを成形品の同心円上の位置に略等間隔に配置するようにするなどの配慮を行い、溶融樹脂材料をキヤビテイ内に注入して成形が行われる。 In recent years, plastic gears, pulleys, and other disk-shaped synthetic resin molded products that are injection-molded by engineering plastics, which are widely used as metal substitutes, require strict accuracy in the roundness and runout of the outer and inner peripheral surfaces. Yes. In order to injection-mold a plastic molded product having such a substantially circular outer periphery with high accuracy, consideration is usually given to arranging a plurality of gates at substantially equal intervals on the concentric circles of the molded product. The molten resin material is injected into the cavity and molding is performed.

特許文献１には、内周に形成される中空のボス部が全周に亘って均一な円筒形でなく、円周方向の一部にキー溝などの異形部が形成される場合には、異形部に対応する位置のゲートを半径方向に移動させることにより、合成樹脂成形品の外周部形状の精度を向上できることが開示されている。 In Patent Document 1, the hollow boss portion formed on the inner periphery is not a uniform cylindrical shape over the entire circumference, and when a deformed portion such as a key groove is formed in a part of the circumferential direction, It is disclosed that the accuracy of the outer peripheral shape of the synthetic resin molded product can be improved by moving the gate at a position corresponding to the deformed portion in the radial direction.

また、特許文献２には、ボス部にキー受容部を設けた樹脂歯車において、多数のリブを半径方向に設けた実施形態が開示されるとともに、キー受容部の周辺形状の工夫により強度向上が図れることが記載されている。
特開２００１―３４１１６７号公報 特開２００４−３０８７３１号公報 Patent Document 2 discloses an embodiment in which a large number of ribs are provided in a radial direction in a resin gear provided with a key receiving portion in a boss portion, and the strength is improved by devising the peripheral shape of the key receiving portion. It is described that it can be achieved.
JP 2001-341167 A JP 2004-308731 A

しかしながら、特許文献１および特許文献２に記載の歯車においては、ボス部にキー溝やキー受容部などの異形部が存在し、周方向において均一な形状となっていないことに起因して、樹脂成形品外周面の精度が低下してしまう虞があった。 However, in the gears described in Patent Document 1 and Patent Document 2, the boss portion has a deformed portion such as a key groove or a key receiving portion, and is not uniform in the circumferential direction. There is a possibility that the accuracy of the outer peripheral surface of the molded product may be lowered.

例えば、ボス部に形成されたキー受容部を構成する壁部が比較的厚肉であるような場合には、金型内に射出された樹脂がキー受容部において固化するのが遅れるために、キー受容部の収縮量が他の部位に比べ比較的大きくなって、その結果、樹脂成形品の外周面形状においても、キー受容部の外周に位置する部位が半径方向内側にくぼむような傾向の精度劣化を示すことがあった。 For example, when the wall portion constituting the key receiving portion formed in the boss portion is relatively thick, the resin injected into the mold is delayed from solidifying in the key receiving portion. The amount of shrinkage of the key receiving part is relatively large compared to other parts. As a result, even in the outer peripheral surface shape of the resin molded product, the part located on the outer periphery of the key receiving part tends to be recessed radially inward. In some cases, the accuracy deteriorated.

逆に、ボス部からウェブ部にかけて、比較的大きなキー溝が切り欠き状に形成されるような樹脂成形品においては、キー溝周辺の樹脂の固化が比較的早いために、キー溝周辺の収縮量が他の部位に比べて小さくなり、その結果、樹脂成形品の外周面形状において、キー溝の外周に位置する部位が半径方向外側にふくらむような傾向の精度劣化を示すことがあった。 Conversely, in resin molded products in which a relatively large key groove is formed in a notch shape from the boss part to the web part, the resin around the key groove hardens relatively quickly, so the shrinkage around the key groove As a result, the amount of the outer peripheral surface of the resin molded product may be less accurate than the other parts, resulting in a deterioration in accuracy that tends to cause the part located on the outer periphery of the keyway to bulge outward in the radial direction.

本発明は、上記に鑑み、ボス部の一部に異形部が形成された合成樹脂成形品を高い寸法精度で射出成形により製造することを課題とするものである In view of the above, it is an object of the present invention to produce a synthetic resin molded product in which a deformed portion is formed on a part of a boss portion by injection molding with high dimensional accuracy.

本発明の発明者は、鋭意検討の結果、ボス部に隣接して半径方向に延設されるリブ部材の肉厚や間隔を、ボスの異形部に隣接するリブとそうでないリブとで異ならせることによって、ボス部の異形部に起因する収縮性の不均一性を補償し、上記課題を解決できることを知見し、本発明を完成させた。 As a result of intensive investigations, the inventor of the present invention makes the thickness and spacing of the rib member extending radially adjacent to the boss portion different between the rib adjacent to the deformed portion of the boss and the other rib. As a result, it was found that the non-uniformity of shrinkage due to the deformed portion of the boss portion can be compensated and the above-mentioned problems can be solved, and the present invention has been completed.

本発明は、外周部に形成された円環状のリムと、内周部に前記リムと同心に設けられたボスと、リムとボスを接続するウェブと、半径方向に延設されたリブとが一体に成形された合成樹脂成形品であって、前記ボスには周方向にわたって半径方向断面形状が変化した異形部が形成されると共に、異形部に接続するリブが、その他のリブに対して異なる肉厚とされてなることを特徴とする合成樹脂成形品である。 The present invention comprises an annular rim formed on the outer peripheral portion, a boss provided concentrically with the rim on the inner peripheral portion, a web connecting the rim and the boss, and a rib extending in the radial direction. An integrally molded synthetic resin molded product, wherein the boss is formed with a deformed portion whose radial cross-sectional shape is changed in the circumferential direction, and ribs connected to the deformed portion are different from other ribs. It is a synthetic resin molded product characterized by being made thick.

上記合成樹脂成形品においては、さらに、合成樹脂成形品の半径方向の断面において、前記ボス異形部の断面積が異形部でないボスの断面積よりも大きい場合には、異形部に接続するリブがその他のリブよりも薄肉とすることが好ましく（請求項２）、または、前記ボス異形部の断面積が異形部でないボスの断面積よりも小さい場合には、異形部に接続するリブがその他のリブよりも厚肉とすることが好ましい（請求項３）。 In the synthetic resin molded product, in the radial cross section of the synthetic resin molded product, if the cross-sectional area of the boss deformed portion is larger than the cross-sectional area of the boss that is not the deformed portion, a rib connected to the deformed portion is provided. Preferably, the rib is thinner than the other ribs (Claim 2), or when the cross-sectional area of the boss deformed portion is smaller than the cross-sectional area of the boss that is not the deformed portion, the rib connected to the deformed portion is the other rib. It is preferable to make it thicker than the rib.

また、本発明は、外周部に形成された円環状のリムと、内周部に前記リムと同心に設けられたボスと、リムとボスを接続するウェブと、半径方向に延設されたリブとが一体に成形された合成樹脂成形品であって、前記ボスには周方向にわたって半径方向断面形状が変化した異形部が形成されると共に、異形部に接続するリブ同士の間隔が、その他のリブ同士の間隔に対して異なる間隔で設けられたことを特徴とする合成樹脂成形品である。（請求項４）。 The present invention also provides an annular rim formed on the outer peripheral portion, a boss provided concentrically with the rim on the inner peripheral portion, a web connecting the rim and the boss, and a rib extending in the radial direction. And the boss is formed with a deformed portion whose radial cross-sectional shape is changed over the circumferential direction, and the interval between the ribs connected to the deformed portion is other than It is a synthetic resin molded product provided at different intervals with respect to the interval between ribs. (Claim 4).

上記合成樹脂成形品においては、さらに、合成樹脂成形品の半径方向の断面において、前記ボス異形部の断面積が異形部でないボスの断面積よりも大きい場合には、ボスの異形部に接続するリブ同士の間隔が、その他のリブ同士の間隔に対して広い間隔で設けられることが好ましく（請求項５）、または、前記ボス異形部の断面積が異形部でないボスの断面積よりも小さい場合には、ボスの異形部に接続するリブ同士の間隔が、その他のリブ同士の間隔に対して狭い間隔で設けられることが好ましい（請求項６）。 In the synthetic resin molded product, when the cross-sectional area of the boss deformed portion is larger than the cross-sectional area of the boss that is not the deformed portion in the radial cross section of the synthetic resin molded product, the boss deformed portion is connected. It is preferable that the interval between the ribs is provided at a wider interval than the interval between the other ribs (Claim 5), or the cross-sectional area of the boss deformed portion is smaller than the cross-sectional area of the boss that is not the deformed portion. It is preferable that the interval between the ribs connected to the deformed portion of the boss is narrower than the interval between the other ribs.

本発明の合成樹脂成形品によれば、ボス部に異形部を有するような成形品であっても、高精度の外周形状を有する成形品が射出成形により製造できるという効果が得られる。
請求項１、請求項２または請求項３の様態においては、リブの肉厚を調整することにより、請求項４、請求項５または請求項６の様態においては、リブの間隔を調整することにより本発明の効果が得られる。
According to the synthetic resin molded product of the present invention, there is an effect that a molded product having a highly accurate outer peripheral shape can be manufactured by injection molding even if the molded product has a deformed portion in the boss portion.
In the aspect of Claim 1, Claim 2 or Claim 3, by adjusting the thickness of the rib, in the aspect of Claim 4, Claim 5 or Claim 6, by adjusting the interval of the rib. The effect of the present invention can be obtained.

以下、図面に基づいて、本発明の実施形態を合成樹脂製歯車を例として説明する。
図１は本発明の第１の実施形態の合成樹脂歯車１を示す正面図である。図２は図１のＸ−Ｘ断面図である。 Hereinafter, an embodiment of the present invention will be described based on a synthetic resin gear as an example based on the drawings.
FIG. 1 is a front view showing a synthetic resin gear 1 according to a first embodiment of the present invention. 2 is a cross-sectional view taken along the line XX of FIG.

合成樹脂歯車１は、円盤状の歯車であり、その外周部には複数の歯部２、２が設けられており、歯部２は円環状のリム３と一体化されている。合成樹脂歯車１の中央部には、その内周面に図示しない軸を嵌着して歯車の軸部をなすボス４が、リム３と同心円状に設けられている。リム３とボス４とは、円盤状のウェブ５によって連結されている。図２の断面にも示されるように、リム３とボス４とウェブ５とによって、厚肉の円盤を薄肉に肉抜きしたような形状が形成されている。さらに、ウェブ５上には、リム３とボス４とを互いに接続するようにリブ６，６が半径方向に延設されている。歯部２、リム３、ボス４、ウェブ５、リブ６は互いに一体に成形されている。 The synthetic resin gear 1 is a disc-shaped gear, and a plurality of tooth portions 2 and 2 are provided on the outer peripheral portion thereof. The tooth portion 2 is integrated with an annular rim 3. A boss 4, which is a shaft portion of the gear by fitting a shaft (not shown) on its inner peripheral surface, is provided concentrically with the rim 3 at the central portion of the synthetic resin gear 1. The rim 3 and the boss 4 are connected by a disc-shaped web 5. As shown in the cross section of FIG. 2, the rim 3, the boss 4, and the web 5 form a shape in which a thick disk is thinned. Furthermore, on the web 5, ribs 6 and 6 extend in the radial direction so as to connect the rim 3 and the boss 4 to each other. The tooth portion 2, the rim 3, the boss 4, the web 5, and the rib 6 are formed integrally with each other.

本発明の合成樹脂歯車は、ポリアセタール樹脂などのエンジニアリングプラスチックや、ポリアミド樹脂などの熱可塑性樹脂を用い、射出成形法により製造することができる。 The synthetic resin gear of the present invention can be manufactured by an injection molding method using an engineering plastic such as a polyacetal resin or a thermoplastic resin such as a polyamide resin.

ボス４の内周穴に挿通嵌着される軸（図示せず）には、キーが設けられ、ボス４には、キーを収蔵するためのキー受容部４２が構成されるように側壁４３が設けられている。キー受容部４２や側壁４３が設けられることにより、合成樹脂歯車１の歯車軸と半径方向を含む平面における断面（以下、半径方向断面）に関して、ボス４周辺の断面形状は、周方向に一定とはならず、キー受容部４２や側壁４３に対応して断面形状が変化する。本実施形態においては、特に半径方向断面が側壁４３を含む場合に、ボス周辺の断面積が大きくなる傾向を示す。言い換えると、ボス４には、キー受容部４２に対応し、半径方向断面形状が歯車の周方向にわたって変化する部分、すなわち異形部が設けられており、本実施形態では、異形部においてボス部の断面積即ちボス部周辺の樹脂の量が増加している。 A shaft (not shown) that is inserted and fitted into the inner peripheral hole of the boss 4 is provided with a key, and the boss 4 has a side wall 43 so that a key receiving portion 42 for storing the key is formed. Is provided. By providing the key receiving portion 42 and the side wall 43, the cross-sectional shape around the boss 4 is constant in the circumferential direction with respect to the cross section in the plane including the gear axis and the radial direction of the synthetic resin gear 1 (hereinafter referred to as the radial cross section). In other words, the cross-sectional shape changes corresponding to the key receiving portion 42 and the side wall 43. In the present embodiment, particularly when the radial cross section includes the side wall 43, the cross-sectional area around the boss tends to increase. In other words, the boss 4 is provided with a portion corresponding to the key receiving portion 42 and having a radial cross-sectional shape that changes in the circumferential direction of the gear, that is, a deformed portion. The cross-sectional area, that is, the amount of resin around the boss is increased.

ボス４とリム３を半径方向に接続するリブ６，６は、ボス４に対して異形部（キー受容部や側壁）に接続するかそうでないかで、その肉厚と間隔を異ならせて設けられている。即ち、異形部に接続するリブ６ａ、６ａ（図示ａ区間に設けられるリブ）は、他のリブ６ｂ、６ｂ（図示ｂ区間に設けられるリブ）よりも、薄肉に（即ち、ｔａ＜ｔｂとなるように）設けられると共に、異形部に接続するリブ６ａ、６ａ同士の間隔Ｗａが、他のリブ６ｂ、６ｂ同士の間隔Ｗｂよりも広く（Ｗａ＞Ｗｂとなるように）設けられている。ここで、リブ６の肉厚および間隔とは、図１に示したように、周方向の厚さ・間隔を言う。 The ribs 6 and 6 that connect the boss 4 and the rim 3 in the radial direction are provided with different thicknesses and intervals depending on whether or not the boss 4 is connected to a deformed portion (key receiving portion or side wall). It has been. That is, the ribs 6a and 6a (ribs provided in the section a in the drawing) connected to the deformed portion are thinner (that is, ta <tb) than the other ribs 6b and 6b (ribs provided in the section b in the drawing). And the interval Wa between the ribs 6a, 6a connected to the deformed portion is wider than the interval Wb between the other ribs 6b, 6b (Wa> Wb). Here, the thickness and interval of the ribs 6 mean the thickness and interval in the circumferential direction, as shown in FIG.

以下、本発明の合成樹脂成形品の作用と効果を説明する。
射出成形法により、金型のキャビティ内に溶融樹脂が射出され、保圧、冷却されて本発明の合成樹脂歯車が製造されるが、本実施形態においては、ボス４の周辺において、キー受容部４２に対応する異形部の樹脂量が多くなっているために、ボス周辺において異形部の冷却が遅れることになり、その結果、異形部の収縮量がボス周辺の他の部分に対し大きくなる傾向を生ずる。一方で、異形部に接続するリブ６ａ、６ａが、他のリブ６ｂ、６ｂよりも、薄肉に設けられているので、リブ６ａ，６ａが設けられる領域は、リブ６ｂ、６ｂが設けられる領域よりも樹脂の冷却が促進され、樹脂の収縮量が小さくなる。その結果、異形部に起因する樹脂収縮量の不均一さを、リブが設けられた部分の樹脂収縮量によって補償し、合成樹脂歯車全体としては、周方向に均一な収縮量となるようにして、歯車外周部分の精度を向上させることができる。 Hereinafter, the operation and effect of the synthetic resin molded product of the present invention will be described.
By the injection molding method, the molten resin is injected into the cavity of the mold, and the pressure is held and cooled to produce the synthetic resin gear of the present invention. In this embodiment, the key receiving portion is provided around the boss 4. Since the amount of resin in the deformed portion corresponding to 42 is increased, the cooling of the deformed portion is delayed around the boss, and as a result, the shrinkage amount of the deformed portion tends to be larger than the other portions around the boss. Is produced. On the other hand, since the ribs 6a and 6a connected to the deformed portion are provided thinner than the other ribs 6b and 6b, the area where the ribs 6a and 6a are provided is more than the area where the ribs 6b and 6b are provided. However, the cooling of the resin is promoted, and the shrinkage amount of the resin is reduced. As a result, the non-uniformity of the resin shrinkage due to the deformed portion is compensated by the resin shrinkage of the portion where the rib is provided, so that the entire synthetic resin gear has a uniform shrinkage in the circumferential direction. The accuracy of the outer peripheral portion of the gear can be improved.

同様に、異形部に接続するリブ６ａ、６ａ同士の間隔（Ｗａ）が、他のリブ６ｂ、６ｂ同士の間隔（Ｗｂ）よりも広く設けられていることによっても、リブ６ａ，６ａが設けられる領域が、リブ６ｂ、６ｂが設けられる領域よりも樹脂の冷却が促進され、樹脂の収縮量が小さくなる傾向が生じ、同じく、異形部に起因する樹脂収縮量の不均一さを、リブが設けられた部分の樹脂収縮量によって補償し、合成樹脂歯車全体としては、周方向に均一な収縮量となるようにして、歯車外周部分の精度を向上させることができる。すなわち、リブ６,６による調整は、リブの肉厚のみを調整してもよいし、リブ同士の間隔のみを調整するものであっても良い。 Similarly, the ribs 6a and 6a are also provided when the interval (Wa) between the ribs 6a and 6a connected to the deformed portion is wider than the interval (Wb) between the other ribs 6b and 6b. The region has a tendency that the cooling of the resin is promoted more than the region where the ribs 6b and 6b are provided, and the shrinkage amount of the resin tends to be small. Similarly, the ribs provide unevenness of the resin shrinkage amount due to the deformed portion. The accuracy of the outer peripheral portion of the gear can be improved by compensating the amount of shrinkage of the resin in the portion so that the entire synthetic resin gear has a uniform amount of contraction in the circumferential direction. That is, the adjustment by the ribs 6 and 6 may be to adjust only the thickness of the ribs or to adjust only the interval between the ribs.

以下に他の実施の形態を示す。
図３は本発明の第２の実施形態の合成樹脂歯車１’を示す正面図である。図４は図３のＸ−Ｘ断面図である。本実施の形態の説明においては、主に第１実施形態と相違する部分を中心に説明し、同様である部分の説明は省略する。 Other embodiments are shown below.
FIG. 3 is a front view showing a synthetic resin gear 1 ′ according to the second embodiment of the present invention. 4 is a sectional view taken along line XX in FIG. In the description of the present embodiment, the description will mainly focus on parts that are different from the first embodiment, and description of the parts that are the same will be omitted.

本実施の形態においては、合成樹脂歯車中央部に、ボス４’とともにキー溝７が設けられている。キー溝７はボス４’の一部およびウェブ５の一部を切り欠いたように設けられている。本実施形態においては、キー溝７に対応する部分が、異形部を構成し、異形部においては他の部分に比べてボス部周辺の半径方向断面の断面積が減少し、ボス部周辺の樹脂の量が減少している。 In the present embodiment, a key groove 7 is provided in the central portion of the synthetic resin gear together with the boss 4 '. The keyway 7 is provided so as to cut out a part of the boss 4 ′ and a part of the web 5. In this embodiment, the portion corresponding to the key groove 7 constitutes a deformed portion, and the cross-sectional area of the radial cross section around the boss portion is smaller in the deformed portion than in other portions, and the resin around the boss portion The amount of is decreasing.

ボス４’またはキー溝７周辺とリム３を半径方向に接続するリブ６’，６’は、内周側において異形部（キー溝周辺部分）に接続するかそうでないかで、その肉厚と間隔を異ならせて設けられている。即ち、異形部に接続するリブ６ａ’、６ａ’（図示ａ区間に設けられるリブ）は、他のリブ６ｂ’、６ｂ’（図示ｂ区間に設けられるリブ）よりも、厚肉に（即ちｔａ’＞ｔｂ’に）設けられると共に、異形部に接続するリブ６ａ’、６ａ’同士の間隔が、他のリブ６ｂ’、６ｂ’同士の間隔よりも狭く（即ちＷａ’＜Ｗｂ’に）設けられている。 The ribs 6 'and 6' that connect the boss 4 'or the periphery of the key groove 7 and the rim 3 in the radial direction may or may not be connected to the deformed portion (key groove peripheral portion) on the inner peripheral side. It is provided with different intervals. That is, the ribs 6a 'and 6a' (ribs provided in the section a shown in the figure) connected to the deformed portion are thicker than the other ribs 6b 'and 6b' (ribs provided in the section b shown in the figure) (that is, ta). The distance between the ribs 6a 'and 6a' connected to the deformed portion is narrower than the distance between the other ribs 6b 'and 6b' (that is, Wa '<Wb'). It has been.

本実施形態においては、ボス４’の周辺において、キー溝７に対応する異形部の樹脂量が少なくなっているために、異形部の冷却が早まることになり、その結果、異形部の収縮量がボス周辺の他の部分に対し小さくなる傾向を生ずる。一方で、異形部に接続するリブ６ａ’、６ａ’が、他のリブ６ｂ’、６ｂ’よりも、厚肉に設けられているので、リブ６ａ’，６ａ’が設けられる領域は、リブ６ｂ’、６ｂ’が設けられる領域よりも樹脂の冷却が遅くなり、樹脂の収縮量が大きくなる。その結果、異形部（キー溝）に起因する樹脂収縮量の不均一さを、リブが設けられた部分の樹脂収縮量によって補償し、合成樹脂歯車全体としては、周方向に均一な収縮量となるようにして、歯車外周部分の精度を向上させることができる。 In the present embodiment, since the amount of resin in the deformed portion corresponding to the key groove 7 is reduced around the boss 4 ′, cooling of the deformed portion is accelerated, and as a result, the contraction amount of the deformed portion. Tends to be smaller than other parts around the boss. On the other hand, since the ribs 6a ′ and 6a ′ connected to the deformed portion are provided thicker than the other ribs 6b ′ and 6b ′, the region where the ribs 6a ′ and 6a ′ are provided is the rib 6b. The cooling of the resin is slower than the region where “, 6b” is provided, and the amount of shrinkage of the resin increases. As a result, non-uniformity in the amount of resin shrinkage caused by the deformed portion (key groove) is compensated by the amount of resin shrinkage in the portion where the ribs are provided, and the entire synthetic resin gear has a uniform shrinkage amount in the circumferential direction. In this way, the accuracy of the outer peripheral portion of the gear can be improved.

同様に、異形部に接続するリブ６ａ’、６ａ’同士の間隔が、他のリブ６ｂ’、６ｂ’同士の間隔よりも狭く（Ｗａ’＜Ｗｂ’）設けられていることによっても、同じく、異形部に起因する樹脂収縮量の不均一さを、リブが設けられた部分の樹脂収縮量によって補償し、合成樹脂歯車全体としては、周方向に均一な収縮量となるようにして、歯車外周部分の精度を向上させることができる。 Similarly, the interval between the ribs 6a ′ and 6a ′ connected to the deformed portion is provided narrower than the interval between the other ribs 6b ′ and 6b ′ (Wa ′ <Wb ′). The non-uniformity of the resin shrinkage caused by the deformed part is compensated by the resin shrinkage of the part where the ribs are provided, and the synthetic resin gear as a whole has a uniform shrinkage in the circumferential direction. The accuracy of the part can be improved.

以上、本発明の実施の形態について説明したが、本発明は以下のような改変を加えて実施することもできる。 Although the embodiments of the present invention have been described above, the present invention can be implemented with the following modifications.

上記実施例においては合成樹脂成形品として歯部２、２を有する合成樹脂歯車を例に説明したが、必ずしも歯車である必要はなく、歯部を有しないプーリーであっても良いことは明らかである。 In the above-described embodiment, the synthetic resin gear having the tooth portions 2 and 2 has been described as an example of the synthetic resin molded product. However, it is not necessarily a gear, and a pulley having no tooth portion may be used. is there.

また、合成樹脂成形品が円盤状である例を示したが、本発明は外周円の直径に比べて軸方向の厚さが比較的小さい円盤状成形品に限定されるものではなく、外周円の直径に比べ軸方向の厚さが比較的大きいような形状（いわゆる円柱状のもの）である合成樹脂成形品も本発明は包含する。 In addition, although an example in which the synthetic resin molded product has a disk shape has been shown, the present invention is not limited to a disk-shaped molded product having a relatively small axial thickness compared to the diameter of the outer circumferential circle. The present invention also includes a synthetic resin molded product having a shape (so-called cylindrical shape) in which the axial thickness is relatively larger than the diameter of the resin.

また、実施例においては、異形部が円周方向に１つある例を示したが、異形部が複数存在する成形品であっても、それぞれの異形部に対応してリブの肉厚や間隔を調整することにより、本発明を実施することができる。 Further, in the embodiment, an example in which there is one deformed portion in the circumferential direction is shown. However, even in a molded product having a plurality of deformed portions, the rib thickness and interval corresponding to each deformed portion are shown. The present invention can be carried out by adjusting.

また、第１実施形態に示したように、異形部が成形品の片側のみに存在する場合には、異形部が存在する側のみについて、リブの肉厚や間隔を調整することがより好ましい。このようにすることで、成形品片側のみに存在する異形部の影響によって円盤状成形品が片側に反り返ってしまう傾向を補償して、振れの少ない高精度な歯車を得ることができる。 Further, as shown in the first embodiment, when the deformed portion exists only on one side of the molded product, it is more preferable to adjust the thickness and interval of the ribs only on the side where the deformed portion exists. By doing so, it is possible to compensate for the tendency of the disk-shaped molded product to warp to the one side due to the influence of the deformed portion existing only on the molded product one side, and to obtain a highly accurate gear with little deflection.

本発明によれば、ボス部の一部に異形部が形成された円盤状合成樹脂成形品であっても、高い寸法精度で射出成形により製造することができる。 According to the present invention, even a disc-shaped synthetic resin molded product in which a deformed portion is formed on a part of the boss portion can be manufactured by injection molding with high dimensional accuracy.

本発明の合成樹脂歯車の第１の実施の形態を示す正面図。The front view which shows 1st Embodiment of the synthetic resin gear of this invention. 図１のＸ−Ｘ断面図。XX sectional drawing of FIG. 本発明の合成樹脂歯車の第２の実施の形態を示す正面図。The front view which shows 2nd Embodiment of the synthetic resin gear of this invention. 図３のＸ−Ｘ断面図。XX sectional drawing of FIG.

符号の説明Explanation of symbols

１ 合成樹脂歯車
２ 歯部
３ リム
４ ボス
４２ キー受容部
４３ 側壁
５ ウェブ
６ リブ
７ キー溝 1 Synthetic resin gear 2 Tooth part 3 Rim 4 Boss 42 Key receiving part 43 Side wall 5 Web 6 Rib 7 Keyway

Claims (6)

外周部に形成された円環状のリムと、内周部に前記リムと同心に設けられたボスと、リムとボスを接続するウェブと、半径方向に延設されたリブとが一体に成形された合成樹脂成形品であって、
前記ボスには周方向にわたって半径方向断面形状が変化した異形部が形成されると共に、
異形部に接続するリブが、その他のリブに対して異なる肉厚とされてなることを特徴とする合成樹脂成形品。 An annular rim formed on the outer peripheral portion, a boss provided concentrically with the rim on the inner peripheral portion, a web connecting the rim and the boss, and a rib extending in the radial direction are integrally formed. A synthetic resin molded product,
The boss is formed with a deformed portion whose radial cross-sectional shape is changed over the circumferential direction,
A synthetic resin molded product characterized in that ribs connected to the deformed portion have different thicknesses relative to other ribs. 合成樹脂成形品の半径方向の断面において、前記ボス異形部の断面積が異形部でないボスの断面積よりも大きく、異形部に接続するリブがその他のリブよりも薄肉であることを特徴とする請求項１に記載の合成樹脂成形品。 The radial cross section of the synthetic resin molded product is characterized in that a cross-sectional area of the boss deformed portion is larger than a cross-sectional area of a boss that is not a deformed portion, and a rib connected to the deformed portion is thinner than other ribs. The synthetic resin molded product according to claim 1. 合成樹脂成形品の半径方向の断面において、前記ボス異形部の断面積が異形部でないボスの断面積よりも小さく、異形部に接続するリブがその他のリブよりも厚肉であることを特徴とする請求項１に記載の合成樹脂成形品。 In the radial cross section of the synthetic resin molded product, the cross-sectional area of the boss deformed portion is smaller than the cross-sectional area of the boss that is not the deformed portion, and the rib connected to the deformed portion is thicker than the other ribs. The synthetic resin molded product according to claim 1. 外周部に形成された円環状のリムと、内周部に前記リムと同心に設けられたボスと、リムとボスを接続するウェブと、半径方向に延設されたリブとが一体に成形された合成樹脂成形品であって、
前記ボスには周方向にわたって半径方向断面形状が変化した異形部が形成されると共に、
異形部に接続するリブ同士の間隔が、その他のリブ同士の間隔に対して異なる間隔で設けられたことを特徴とする合成樹脂成形品。 An annular rim formed on the outer peripheral portion, a boss provided concentrically with the rim on the inner peripheral portion, a web connecting the rim and the boss, and a rib extending in the radial direction are integrally formed. A synthetic resin molded product,
The boss is formed with a deformed portion whose radial cross-sectional shape is changed over the circumferential direction,
A synthetic resin molded product, characterized in that the interval between ribs connected to the deformed portion is different from the interval between other ribs. 合成樹脂成形品の半径方向の断面において、前記ボス異形部の断面積が異形部でないボスの断面積よりも大きく、ボスの異形部に接続するリブ同士の間隔が、その他のリブ同士の間隔に対して広い間隔で設けられたことを特徴とする請求項４に記載の合成樹脂成形品。 In the radial cross section of the synthetic resin molded product, the cross-sectional area of the boss deformed portion is larger than the cross-sectional area of the boss that is not the deformed portion, and the interval between the ribs connected to the deformed portion of the boss is the interval between the other ribs. The synthetic resin molded product according to claim 4, wherein the synthetic resin molded product is provided at a wide interval. 合成樹脂成形品の半径方向の断面において、前記ボス異形部の断面積が異形部でないボスの断面積よりも小さく、ボスの異形部に接続するリブ同士の間隔が、その他のリブ同士の間隔に対して狭い間隔で設けられたことを特徴とする請求項４に記載の合成樹脂成形品。 In the radial cross section of the synthetic resin molded product, the cross-sectional area of the boss deformed portion is smaller than the cross-sectional area of the boss that is not the deformed portion, and the interval between the ribs connected to the deformed portion of the boss is the interval between the other ribs. The synthetic resin molded product according to claim 4, wherein the synthetic resin molded product is provided at a narrow interval.
JP2008052767A 2008-03-04 2008-03-04 Synthetic resin molded product Expired - Fee Related JP4860650B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2008052767A JP4860650B2 (en) 2008-03-04 2008-03-04 Synthetic resin molded product

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2008052767A JP4860650B2 (en) 2008-03-04 2008-03-04 Synthetic resin molded product

Publications (2)

Publication Number Publication Date
JP2009210005A JP2009210005A (en) 2009-09-17
JP4860650B2 true JP4860650B2 (en) 2012-01-25

Family

ID=41183358

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2008052767A Expired - Fee Related JP4860650B2 (en) 2008-03-04 2008-03-04 Synthetic resin molded product

Country Status (1)

Country Link
JP (1) JP4860650B2 (en)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH039873U (en) * 1989-06-17 1991-01-30
JP2000110919A (en) * 1998-10-02 2000-04-18 Enplas Corp Molded gear of synthetic resin
JP3763449B2 (en) * 2000-06-02 2006-04-05 タイガースポリマー株式会社 Plastic molded product
JP4492842B2 (en) * 2003-04-04 2010-06-30 株式会社エンプラス Resin gear and resin rotational power transmission member

Also Published As

Publication number Publication date
JP2009210005A (en) 2009-09-17

Similar Documents

Publication Publication Date Title
KR101697849B1 (en) Multicomponent gear
JP2008279619A (en) Injection molding gear
US20080118357A1 (en) Turbofan and manufacturing method thereof
JP2008213393A (en) Resin-enveloped component
JP2004338140A (en) Injection molded resin gear, its manufacturing method, injection molded resin rotary body and its manufacturing method
JP2006070914A (en) Plastic gear
US7069805B2 (en) Driving force transmission device
KR101577998B1 (en) Manufacturing method of a resin gear
JP4860650B2 (en) Synthetic resin molded product
JP2019171858A (en) Toric resin molding and composite member
JP5264447B2 (en) Cyclic resin molded product
JP3910022B2 (en) Cyclic resin molded product
JP2008290402A (en) Manufacturing method for synthetic resin pulley, and mold for injection molding
JP5517345B2 (en) Manufacturing method of resin molded products
JP2022121031A (en) Insert molded product and manufacturing method thereof
JP5443089B2 (en) Plastic molded product
JP2017087555A (en) Synthetic resin molded body and manufacturing method therefor
EP2175169B1 (en) Pulley and rolling bearing with resin pulley
WO2019189054A1 (en) Annular resin molded body and composite member
JP5483145B2 (en) Rolling bearing with pulley and resin pulley
JP2011137517A (en) Resin pulley
JP4104318B2 (en) Synthetic resin gear
JP5284145B2 (en) Resin molded product with annular outer periphery
JP2006220176A (en) Synthetic resin gear
JP2000346176A (en) Plastic molded product

Legal Events

Date Code Title Description
RD04 Notification of resignation of power of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7424

Effective date: 20100706

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20100712

TRDD Decision of grant or rejection written
A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20111027

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20111101

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20111102

R150 Certificate of patent or registration of utility model

Ref document number: 4860650

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20171111

Year of fee payment: 6

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees