JPS6360065B2 - - Google Patents
Info
- Publication number
- JPS6360065B2 JPS6360065B2 JP22756783A JP22756783A JPS6360065B2 JP S6360065 B2 JPS6360065 B2 JP S6360065B2 JP 22756783 A JP22756783 A JP 22756783A JP 22756783 A JP22756783 A JP 22756783A JP S6360065 B2 JPS6360065 B2 JP S6360065B2
- Authority
- JP
- Japan
- Prior art keywords
- rubber
- weight
- toothed
- parts
- heat resistance
- 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
Links
- 229920001971 elastomer Polymers 0.000 claims description 37
- 239000000203 mixture Substances 0.000 claims description 19
- 229920002681 hypalon Polymers 0.000 claims description 10
- CPGFMWPQXUXQRX-UHFFFAOYSA-N 3-amino-3-(4-fluorophenyl)propanoic acid Chemical compound OC(=O)CC(N)C1=CC=C(F)C=C1 CPGFMWPQXUXQRX-UHFFFAOYSA-N 0.000 claims description 4
- 229910001860 alkaline earth metal hydroxide Inorganic materials 0.000 claims description 4
- OFHMODDLBXETIK-UHFFFAOYSA-N methyl 2,3-dichloropropanoate Chemical compound COC(=O)C(Cl)CCl OFHMODDLBXETIK-UHFFFAOYSA-N 0.000 claims description 4
- 238000004073 vulcanization Methods 0.000 description 4
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 3
- 239000000920 calcium hydroxide Substances 0.000 description 3
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 3
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 description 3
- 239000000347 magnesium hydroxide Substances 0.000 description 3
- 229910001862 magnesium hydroxide Inorganic materials 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000004744 fabric Substances 0.000 description 2
- 238000009472 formulation Methods 0.000 description 2
- 229920001084 poly(chloroprene) Polymers 0.000 description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 239000006057 Non-nutritive feed additive Substances 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 230000003712 anti-aging effect Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 229910000000 metal hydroxide Inorganic materials 0.000 description 1
- 150000004692 metal hydroxides Chemical class 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- RGSFGYAAUTVSQA-UHFFFAOYSA-N pentamethylene Natural products C1CCCC1 RGSFGYAAUTVSQA-UHFFFAOYSA-N 0.000 description 1
- 125000004817 pentamethylene group Chemical group [H]C([H])([*:2])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[*:1] 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920005862 polyol Polymers 0.000 description 1
- 150000003077 polyols Chemical class 0.000 description 1
- 239000012744 reinforcing agent Substances 0.000 description 1
- -1 softeners Substances 0.000 description 1
- 230000001988 toxicity Effects 0.000 description 1
- 231100000419 toxicity Toxicity 0.000 description 1
- BOXSVZNGTQTENJ-UHFFFAOYSA-L zinc dibutyldithiocarbamate Chemical compound [Zn+2].CCCCN(C([S-])=S)CCCC.CCCCN(C([S-])=S)CCCC BOXSVZNGTQTENJ-UHFFFAOYSA-L 0.000 description 1
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
- F16G1/00—Driving-belts
- F16G1/28—Driving-belts with a contact surface of special shape, e.g. toothed
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Description
本発明は、歯付ベルトに関し、特に歯付ベルト
の背面部、歯形などに耐熱性にすぐれたクロロス
ルホン化ポリエチレンゴム組成物を使用すること
により、従来の歯付ベルトに比し、背ゴムのクラ
ツクの発生を防ぎ、ベルトライフを向上せしめた
歯付ベルトに関する。
従来の歯付ベルトの故障現象は、図に示すベル
ト背面ゴム層１にクラツクが発生して（以下、背
面クラツクという）寿命に至るか、または、歯元
５において、心線２下部と歯形ゴム３との接着界
面で亀裂が発生し（以下、歯元クラツクという）、
歯かけを生じ、寿命に至る場合が大部分を占めて
いる。
このうち、歯元クラツクは、主に心線２と歯形
ゴム３との接着性及び歯形ゴムの強度並びにゴム
付帆布からなる下布５の強度、伸びに起因して発
生し、背面クラツクは主に背ゴムの耐熱性、耐屈
曲性に起因して発生する。
このような歯付ベルトの故障現象のうち歯元ク
ラツクに対しては心線と歯形ゴムの接着性の改
良、下布の改良、及び歯形ゴムの強度を上げるこ
とが、また背面クラツクに対しては、主に背ゴム
の耐熱性の向上によりベルトライフを向上させる
検討が従来より行なわれている。
特に、近年、高温雰囲気下でのベルトライフ向
上の要求が強く、歯付ベルトの耐熱性向上が望ま
れ、一般的には該ベルトの耐熱向上の方策として
耐熱性の改良されたクロロプレンゴム組成物、ク
ロロスルホン化ポリエチレンゴム組成物等を、背
ゴム及び歯形ゴムに適用することが、種々検討さ
れている。また、一般的に、クロロプレンゴム組
成物より耐熱性が良好であるクロロスルホン化ポ
リエチレンゴム組成物のにおいては、クロロスル
ホン化ポリエチレン／金属酸化物／有機促進剤ゴ
ム組成物、クロロスルホン化ポリエチレン／酸化
マグネシウム／ポリオール／有機促進剤ゴム組成
物等が適用されているが、未だ充分な耐熱歯付ベ
ルトを得るには至つていない。
また、歯付ベルト走行時は、雰囲気温度プラス
走行による発熱が加味された高温雰囲気となり使
用されるゴム組成物の耐熱性はベルトライフ向上
のために、非常に重要である。
そこで、このような問題点を解決すべく、本発
明者等は、かねてより鋭意研究を重ねた結果、ク
ロロスルホン化ポリエチレンに水酸化マグネシウ
ム、水酸化カルシウムのうち一種または二種、加
硫促進剤としてジペンタメチルチウラムテトラサ
ルフアイド、ジペンタメチレンチウラムヘキササ
ルフアイドのうち一種または二種を添加混合し
た、ゴム組成物を歯付ベルトの背ゴム及び歯形ゴ
ムに使用することにより、背ゴム、歯形ゴムの耐
熱性を向上せしめ、歯付ベルトの高温雰囲気での
寿命を、従来に比し、著しく向上せしめることを
見出した。
しかるに、本発明の耐熱性歯付ベルトに使用す
るゴム組成物の詳細は、クロロスルホン化ポリエ
チレン100重量部に対し、一般式Ｍ（OH）2で表わ
されるマルカリ土類金属の水酸化物１〜20重量部
加硫促進剤、ジペンタメチレンチウラムテトラサ
ルフアイドまたはジペンタメチレンチウラムヘキ
ササルフアイド１〜５重量部であるが就中、アル
カリ土類金属の水酸化物は４〜10重量部、ジペン
タメチレンチウラムテトラサルフアイドまたはジ
ペンタメチレンチウラムヘキササルフアイドは２
〜３重量部が好ましい範囲である。
ここでアルカリ土類金属の水酸化物が１重量部
未満では耐熱性を向上させる効果に乏しく、20重
量部をこえると、加硫物の破断時伸びの低下の原
因となる。
又、ジペンタメチレンチウラムテトラサルフア
イドまたはジペンタメチレンチウラムヘキササル
フアイドが１重量部未満では、加硫が十分でな
く、５重量部をこえると、スコーチタイムが短か
くなり、また破断時伸びの低下の如く好ましくな
い現象をおこす。
ここで使用されるクロロスルホン化ポリエチレ
ンとしては、特に限定れれるものではないが、耐
熱性、耐油性、耐寒性などのパランスから、塩素
含有量が20〜35％が好適であり、二種以上の塩素
含有量のものを適宜ブランドすることも可能であ
る。
用いる受酸剤は、特に制限されないが、好まし
くは酸化マグネシウムエポキシ樹脂等が用いられ
る。また、リサージを用いる場合においても、ア
ルカリ土類金属の水酸化物の添加により、耐熱性
を向上させることが知見されたが、毒性上の問題
がある。
また使用される老化防止剤も特に制限されない
が、ニツケルジブチルジチオカルバメートが最適
であり、ゴムへの配合量はクロロスルホン化ポリ
エチレン100重量部に対し、１〜５重量部が好ま
しい範囲である。
その他、補強剤、充填剤、軟化剤、加工助剤、
粘着剤等は特に制限されるものではなく、目的に
応じ適宜配合される。
次に前記各成分を混合する方法としては、特に
制限はなく例えばバンバリーミキサー、ニーダ
ー、二本ロールなどを用い適宜、公知の手段、方
法によつて混練することができる。
なお、本発明の歯付ベルトを成型するにあた
り、その方法は従来適用されている種々の公知の
手段を使用することができ、何ら制限されるもの
ではない。
本発明を以下の実施例により更に説明するが、
本発明は勿論、実施例に限定されにものではな
く、本発明を逸脱しない範囲において適宜改変可
能である。
（実施例）
歯付ベルトの背ゴム、および底ゴム用ゴム組成
物の配合を下記第１表に示した。
表中、Ｈ−１は、水酸化マグネシウムをＨ−２
は水酸化カルシウムを使用した本発明歯付ベルト
用ゴム、組成物である。
The present invention relates to a toothed belt, and in particular, by using a chlorosulfonated polyethylene rubber composition with excellent heat resistance for the back surface, tooth profile, etc. of the toothed belt, the back rubber becomes stronger than conventional toothed belts. This invention relates to a toothed belt that prevents the occurrence of cracks and improves belt life. The failure phenomenon of conventional toothed belts is that a crack occurs in the back rubber layer 1 of the belt (hereinafter referred to as a back crack) as shown in the figure, leading to the end of its life, or the lower part of the core wire 2 and the toothed rubber at the tooth root 5. A crack occurred at the adhesive interface with 3 (hereinafter referred to as a root crack),
In most cases, the teeth become stuck, leading to the end of their service life. Of these, tooth root cracks occur mainly due to the adhesion between the core wire 2 and the toothed rubber 3, the strength of the toothed rubber, and the strength and elongation of the lower cloth 5 made of rubberized canvas. This occurs due to the heat resistance and bending resistance of the back rubber. Among these failure phenomena of toothed belts, cracks at the tooth base can be treated by improving the adhesion between the core wire and the toothed rubber, improving the lower fabric, and increasing the strength of the toothed rubber. In the past, studies have been conducted to improve the belt life mainly by improving the heat resistance of the back rubber. In particular, in recent years, there has been a strong demand for improved belt life in high-temperature atmospheres, and it is desired to improve the heat resistance of toothed belts.In general, chloroprene rubber compositions with improved heat resistance are used as a measure to improve the heat resistance of such belts. Various studies have been made to apply chlorosulfonated polyethylene rubber compositions and the like to back rubber and tooth rubber. In general, chlorosulfonated polyethylene rubber compositions that have better heat resistance than chloroprene rubber compositions include chlorosulfonated polyethylene/metal oxide/organic accelerator rubber compositions, chlorosulfonated polyethylene/oxidized Magnesium/polyol/organic accelerator rubber compositions and the like have been applied, but a sufficiently heat-resistant toothed belt has not yet been obtained. Further, when the toothed belt runs, the atmosphere is at a high temperature including the ambient temperature plus the heat generated by running, and the heat resistance of the rubber composition used is very important in order to improve the life of the belt. Therefore, in order to solve these problems, the present inventors have conducted intensive research for some time and found that one or two of magnesium hydroxide, calcium hydroxide, and a vulcanization accelerator are added to chlorosulfonated polyethylene. By using a rubber composition in which one or two of dipentamethylenethiuram tetrasulfide and dipentamethylenethiuram hexasulfide are added and mixed as the back rubber and tooth profile rubber of a toothed belt, the back rubber and tooth profile can be improved. It has been found that the heat resistance of rubber is improved, and the life of toothed belts in high-temperature atmospheres is significantly improved compared to conventional belts. However, the details of the rubber composition used in the heat-resistant toothed belt of the present invention are as follows: 1 to 100 parts by weight of chlorosulfonated polyethylene, 1 to 100 parts by weight of marcal earth metal hydroxide represented by the general formula M(OH) 2 20 parts by weight of vulcanization accelerator, 1 to 5 parts by weight of dipentamethylenethiuram tetrasulfide or dipentamethylenethiuram hexasulfide, especially 4 to 10 parts by weight of alkaline earth metal hydroxide, Pentamethylene lentithuram tetrasulfide or dipentamethylene lentithuram hexasulfide is 2
The preferred range is 3 parts by weight. Here, if the alkaline earth metal hydroxide is less than 1 part by weight, the effect of improving heat resistance is poor, and if it exceeds 20 parts by weight, it causes a decrease in elongation at break of the vulcanizate. In addition, if dipentamethylenethiuram tetrasulfide or dipentamethylenethiuram hexasulfide is less than 1 part by weight, vulcanization will not be sufficient, and if it exceeds 5 parts by weight, the scorch time will be shortened and the elongation at break will be reduced. This causes undesirable phenomena such as deterioration. The chlorosulfonated polyethylene used here is not particularly limited, but from the viewpoint of heat resistance, oil resistance, cold resistance, etc., it is preferable to have a chlorine content of 20 to 35%, and two or more types. It is also possible to appropriately brand products with a chlorine content of . The acid acceptor used is not particularly limited, but preferably magnesium oxide epoxy resin or the like is used. Furthermore, even when using Resurge, it has been found that heat resistance can be improved by adding an alkaline earth metal hydroxide, but there is a problem with toxicity. The anti-aging agent used is also not particularly limited, but nickel dibutyl dithiocarbamate is most suitable, and the amount incorporated into the rubber is preferably from 1 to 5 parts by weight per 100 parts by weight of chlorosulfonated polyethylene. In addition, reinforcing agents, fillers, softeners, processing aids,
Adhesives and the like are not particularly limited, and may be blended as appropriate depending on the purpose. Next, the method for mixing the above-mentioned components is not particularly limited, and can be appropriately kneaded by any known means or method using, for example, a Banbury mixer, a kneader, a two-roll mill, or the like. Note that, in molding the toothed belt of the present invention, various conventionally known means can be used, and the method is not limited in any way. The invention will be further illustrated by the following examples,
The present invention is, of course, not limited to the examples, and can be modified as appropriate without departing from the scope of the present invention. (Example) The formulations of rubber compositions for back rubber and bottom rubber of toothed belts are shown in Table 1 below. In the table, H-1 is magnesium hydroxide, H-2
is a rubber composition for toothed belts of the present invention using calcium hydroxide.
【表】
前記配合にもとづきバンバリーミキサーで混練
し、その配合物を、通常の加硫条件153℃×30分
で加硫した。加硫物の物性は第２表の如くであつ
た。[Table] Based on the above formulation, the mixture was kneaded using a Banbury mixer, and the mixture was vulcanized under normal vulcanization conditions at 153°C for 30 minutes. The physical properties of the vulcanizate were as shown in Table 2.
【表】
第２表より明らかな如く、本発明歯付ベルト用
ゴム組成物は、熱老化後のモジユラス、伸度の変
化率が比較例に比べ小さく耐熱性が良好であるこ
とを示している。
次に前記第１表に示す各配合ゴムを使用した歯
付ベルトＡ型（長さ31.5インチ、巾0.75インチ、
ポリアミド心線を使用）を作成し、走行試験を行
なつた。その結果を第３表に示した。[Table] As is clear from Table 2, the rubber composition for toothed belts of the present invention has a smaller change rate in modulus and elongation after heat aging than the comparative examples, indicating that it has good heat resistance. . Next, type A toothed belt (length 31.5 inches, width 0.75 inches,
(using polyamide core wire) and conducted running tests. The results are shown in Table 3.
【表】
走行試験は、駆動プーリ（歯数18、7200rpm）、
従動プーリ（歯数36、3600rpm）、アイドラープ
ーリ（62φ）負荷５馬力で行なつた。
上記第３表から明らかなように、水酸化マグネ
シウムまたは水酸化カルシウムを添加したゴム組
成物を使つた本発明歯付ベルトは従来の歯付ベル
トに比し熱間走行試験における背面クラツク発生
までの時間が長く本発明の歯付ベルトが顕著な効
果を奏することが窺知される。[Table] In the running test, the drive pulley (18 teeth, 7200 rpm),
The test was carried out using a driven pulley (36 teeth, 3600 rpm) and an idler pulley (62φ) with a load of 5 horsepower. As is clear from Table 3 above, the toothed belt of the present invention, which uses a rubber composition containing magnesium hydroxide or calcium hydroxide, has a higher resistance to cracking on the back surface in the hot running test than the conventional toothed belt. It can be seen that the toothed belt of the present invention exhibits remarkable effects over a long period of time.
図は本発明実施例に係る歯付ベルトの部分側面
図である。
１……背ゴム（背面ゴム層）、２……心線、３
……歯形ゴム、４……歯元、５……ゴム付帆布。
The figure is a partial side view of a toothed belt according to an embodiment of the present invention. 1... Back rubber (back rubber layer), 2... Core wire, 3
...Tooth-shaped rubber, 4...Tooth base, 5...Rubber canvas.
Claims (1)
対し、一般式Ｍ（OH）2で表わされるアルカリ土
類金属の水酸化物を１〜20重量部、ジペンタメチ
レンチウラムテトラサルフアイドまたはジペンタ
メチレンチウラムヘキササルフアイド１〜５重量
部からなるゴム組成物を背ゴム、歯形ゴムに用い
て構成したことを特徴とする耐熱性歯付ベルト。1. For 100 parts by weight of chlorosulfonated polyethylene, add 1 to 20 parts by weight of an alkaline earth metal hydroxide represented by the general formula M(OH) 2 , dipentamethylenethiuram tetrasulfide or dipentamethylenethiuram hexasulfide. A heat-resistant toothed belt characterized in that a rubber composition containing 1 to 5 parts by weight of id is used for the back rubber and the toothed rubber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22756783A JPS60121341A (en) | 1983-11-30 | 1983-11-30 | Heat-resisting toothed belt |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22756783A JPS60121341A (en) | 1983-11-30 | 1983-11-30 | Heat-resisting toothed belt |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60121341A JPS60121341A (en) | 1985-06-28 |
| JPS6360065B2 true JPS6360065B2 (en) | 1988-11-22 |
Family
ID=16862935
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22756783A Granted JPS60121341A (en) | 1983-11-30 | 1983-11-30 | Heat-resisting toothed belt |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60121341A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63157548U (en) * | 1987-03-31 | 1988-10-17 | ||
| JP2015124318A (en) * | 2013-12-26 | 2015-07-06 | 東ソー株式会社 | Chlorosulfonated polyolefin composition |
-
1983
- 1983-11-30 JP JP22756783A patent/JPS60121341A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60121341A (en) | 1985-06-28 |
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