JP2000514743A - Manufacturing method of lightweight steering wheel - Google Patents
Manufacturing method of lightweight steering wheelInfo
- Publication number
- JP2000514743A JP2000514743A JP10547735A JP54773598A JP2000514743A JP 2000514743 A JP2000514743 A JP 2000514743A JP 10547735 A JP10547735 A JP 10547735A JP 54773598 A JP54773598 A JP 54773598A JP 2000514743 A JP2000514743 A JP 2000514743A
- Authority
- JP
- Japan
- Prior art keywords
- steering wheel
- granules
- cover layer
- mold
- wheel body
- 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.)
- Pending
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 238000000034 method Methods 0.000 claims abstract description 23
- 239000008187 granular material Substances 0.000 claims abstract description 15
- 239000000463 material Substances 0.000 claims abstract description 11
- 239000004033 plastic Substances 0.000 claims abstract description 9
- 229920003023 plastic Polymers 0.000 claims abstract description 9
- 230000005484 gravity Effects 0.000 claims abstract description 7
- -1 polypropylene Polymers 0.000 claims abstract description 7
- 238000010438 heat treatment Methods 0.000 claims abstract description 5
- 239000004743 Polypropylene Substances 0.000 claims abstract description 4
- 229920001155 polypropylene Polymers 0.000 claims abstract description 4
- 239000004698 Polyethylene Substances 0.000 claims abstract description 3
- 239000002184 metal Substances 0.000 claims abstract description 3
- 239000002245 particle Substances 0.000 claims abstract description 3
- 229920000573 polyethylene Polymers 0.000 claims abstract description 3
- 239000004604 Blowing Agent Substances 0.000 claims abstract 2
- 239000004814 polyurethane Substances 0.000 claims description 4
- 239000004088 foaming agent Substances 0.000 claims description 3
- 238000000465 moulding Methods 0.000 claims description 3
- 238000002844 melting Methods 0.000 claims description 2
- 230000008018 melting Effects 0.000 claims description 2
- 229920003225 polyurethane elastomer Polymers 0.000 claims 1
- 239000000126 substance Substances 0.000 claims 1
- 229920002725 thermoplastic elastomer Polymers 0.000 claims 1
- 229920000426 Microplastic Polymers 0.000 abstract 1
- 239000011248 coating agent Substances 0.000 abstract 1
- 238000000576 coating method Methods 0.000 abstract 1
- 229920002635 polyurethane Polymers 0.000 description 3
- 239000006260 foam Substances 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 239000010985 leather Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 230000035807 sensation Effects 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
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
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/02—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles
- B29C44/04—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles consisting of at least two parts of chemically or physically different materials, e.g. having different densities
- B29C44/06—Making multilayered articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D1/00—Steering controls, i.e. means for initiating a change of direction of the vehicle
- B62D1/02—Steering controls, i.e. means for initiating a change of direction of the vehicle vehicle-mounted
- B62D1/04—Hand wheels
-
- 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
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/02—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles for articles of definite length, i.e. discrete articles
- B29C44/12—Incorporating or moulding on preformed parts, e.g. inserts or reinforcements
-
- 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
- B29C44/00—Shaping by internal pressure generated in the material, e.g. swelling or foaming ; Producing porous or cellular expanded plastics articles
- B29C44/34—Auxiliary operations
- B29C44/36—Feeding the material to be shaped
- B29C44/38—Feeding the material to be shaped into a closed space, i.e. to make articles of definite length
- B29C44/44—Feeding the material to be shaped into a closed space, i.e. to make articles of definite length in solid form
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Steering Controls (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
Abstract
(57)【要約】 低質量慣性モーメントを有するステアリングホイールを製造するために、金属製ステアリングホイール骨格の周りにプラスチック材料を被せる方法が開示される。この方法は、ステアリングホイール骨格、及び発泡剤と混合された所定量のサーモマー(thermomer)プラスチックの粒体、特にポリプロピレン又はポリエチレンの粒体をステアリングホイール用金型に導入し、その粒体を少なくとも100℃に加熱することを特徴とする。そのステアリングホイール用金型内でそれら粒体粒子は発泡、溶融及び結合せしめられて、ステアリングホイール骨格を包囲しているステアリングホイール体を形成する。このステアリングホイール体は内部において発泡せしめられて、外側に実質的に閉じた表面を与え、また0.4g/cm3未満の比重を有する。 SUMMARY A method is disclosed for coating a plastic material around a metal steering wheel skeleton to produce a steering wheel having a low mass moment of inertia. The method comprises introducing a steering wheel backbone and a predetermined amount of thermomer plastic granules, especially polypropylene or polyethylene granules mixed with a blowing agent, into a steering wheel mold and subjecting the granules to at least 100 granules. It is characterized by heating to ° C. In the steering wheel mold, the particulate particles are foamed, melted and bonded to form a steering wheel body surrounding the steering wheel framework. The steering wheel body is foamed internally to provide a substantially closed surface on the outside and has a specific gravity of less than 0.4 g / cm 3 .
Description
【発明の詳細な説明】 軽量ステアリングホイールの製造法 説明 本発明は、金属製ステアリングホイール骨格構造体を成形技術によりプラスチ ックで包むことによって、慣性モーメントの小さいステアリングホイールを製造 する方法に関する。 上記のような方法はずっと以前から知られていた。即ち、初めは、1.18〜 1.39g/cm3の比重を有するCAB及びPVCのようなサーモメリック性の材料(th ermomeric material)が用いられた。商業的な自走車では、0.89〜0.93 g/cm3の比重を有する射出成形ポリプロピレンのケーシングが今でも使用されて いる。乗用車の分野では、これらの材料は大部分ポリウレタンで取って代わられ た。このポリウレタンからは、発泡剤の混合により、微孔質構造を有するコア域 が、気孔を著しくは含まない、触感に優れた、緻密なカバー層で包囲されている 、いわゆる一体型フォーム構造体を製造することが可能である。これによって、 ほぼ0.8g/cm3と言う比重を有するステアリングホイールのケーシングが得ら れる。 最新の乗用車では、操行システムのパラメーターが高能動性運転安全性(high active driving safety)に関して相互に非常に細かく調整されているので、ド ライバーは僅かな変化でもそれらを外乱であると感じるようになっている。多く の場合、特に前輪駆動の場合、その操行システムはステアリングホイールの質量 慣性モーメント(mass inertia moment)を低下させることによって更なる改善 を図ることができる。装備されているステアリングホイール構造体、即ち、特に ステアリングホイールの骨格構造体の材料消費量は、運転性と事故に関して、安 全性に制限を加えることなく、これ以上少なくすることはできないので、ケーシ ングの慣性質量を更に低下させることは相当に重要なことである。 かくして、ステアリングホイールの骨格構造体を成形技術で包む既知の方法を 、ステアリングホイールの質量慣性モーメントを、外の場合は許容されている欠 点 なしに、更に低下させることができるように、更に発展させると言う目的が現に 存在するのである。言い換えると、運転性と安全性に関して、今日の乗用車に常 用されているステアリングホイールと技術的に少なくとも同じレベルにあり、機 能上、触感上及び美的面での何らかの考慮要件にこの標準に比較して欠点がなく 、それにも関わらず質量慣性モーメントが明白に低いステアリングホイールを製 造すべきなのである。 この問題は次の本発明により解決される。即ち、本発明においては、ステアリ ングホイールの骨格構造体、並びに発泡剤と混合されたサーモメリック性プラス チック、特にポリプロピレン又はポリエチレンより成る粒体を所定の量でステア リングホイール用金型に導入し、その粒体を少なくとも100℃に加熱し、そし てそのステアリングホイール用金型中でのそれら粒体粒子の発泡、溶融及び結合 により、比重が0.4g/cm3未満のステアリングホイール体をステアリングホイ ールの骨格構造体を包囲して形成し、内部発泡させて、外側に実質的に閉じた表 面を与える。 ケーシング材料の比重をポリウレタンの一体型フォームに関して従来最も有利 な値と比較して半分以下に下げることにより、ステアリングホイールの骨格構造 体の材料消費量を同じに保ちながら、そのステアリングホイールの質量慣性モー メントを相当に低下させることができる。それは、本発明に従って加工される材 料はその最大割合がステアリングホイール・リングの中に配されるからである。 ステアリングホイールの重量を下げることも、車両構造体の重量を低下させる と言う一般的な経済目的に沿うものである。更に、使用される材料は高い加工コ ストを掛けずにリサイクルすることができ、従ってその使用は生態環境上の観点 からも歓迎されるべきものとである。 本願の実施態様項2〜8には、全て本発明の基本的着想に基づく有利な各種の 別法が記載される。これらの別法によれば、発泡させることができるサーモメリ ック性プラスチックからステアリングホイールのカバーが製造される。これら態 様を実施すると、多くの場合容易かつ十分に耐摩耗性でしかも触感上満足な緻密 な表面が得られ、それは、勿論、その全体又は一部を、自体公知の方法で、革、 木質薄板又はそれらと同等の材料のカバー層でカバーすることができる。大量生 産には、また、本願の実施態様項9〜13に記載されるとおり、第二の操作工程 で適切なプラスチックのカバー層を施すことができる。 以上によって、一方では、特に低い質量慣性モーメントを有するステアリング ホイールの製造を可能とし、他方では、いかなる機能上の制約も加えることなく 、通常の表面をあらゆる点で改善することを可能とする方法が示される。DETAILED DESCRIPTION OF THE INVENTION lightweight steering wheel manufacturing method described invention, by wrapping a plastic by a molding technique metal steering wheel skeleton structure, a method for producing a small steering wheel moment of inertia. Such a method has been known for a long time. That is, initially, a thermomeric material such as CAB and PVC having a specific gravity of 1.18 to 1.39 g / cm 3 was used. In commercial motor vehicles, injection molded polypropylene casings with specific gravities between 0.89 and 0.93 g / cm 3 are still used. In the field of passenger cars, these materials have largely been replaced by polyurethane. From this polyurethane, by mixing a foaming agent, a so-called integral foam structure in which a core region having a microporous structure is surrounded by a dense cover layer that does not significantly contain pores and has an excellent tactile sensation. It is possible to manufacture. This results in a steering wheel casing having a specific gravity of approximately 0.8 g / cm 3 . In modern passenger cars, the parameters of the operating system are very finely tuned with respect to each other with regard to high active driving safety, so that even small changes make the driver feel them as disturbances. I have. In many cases, especially in the case of front-wheel drive, the steering system can provide further improvement by reducing the mass inertia moment of the steering wheel. Since the material consumption of the equipped steering wheel structure, in particular the skeleton structure of the steering wheel, cannot be reduced further without impairing safety, in terms of drivability and accidents, the casing It is of considerable importance to further reduce the inertial mass. Thus, the known method of encapsulating the steering wheel skeletal structure with molding techniques is further developed so that the mass moment of inertia of the steering wheel can be further reduced without the disadvantages otherwise allowed. The purpose exists in reality. In other words, driving and safety are at least at the same technical level as the steering wheel commonly used in today's passenger cars, and some functional, tactile and aesthetic considerations are compared to this standard. Steering wheels should be manufactured that are free of drawbacks and yet have a significantly lower mass moment of inertia. This problem is solved by the following invention. That is, in the present invention, a predetermined amount of granules made of a skeletal structure of a steering wheel and a thermomeric plastic mixed with a foaming agent, particularly polypropylene or polyethylene, are introduced into a steering wheel mold, and the granules are introduced. Heating the body to at least 100 ° C., and expanding, melting and bonding the granular particles in the steering wheel mold to reduce the specific gravity of the steering wheel body to less than 0.4 g / cm 3 to the structure of the steering wheel. Formed around the body and foamed internally to provide a substantially closed surface on the outside. By lowering the specific gravity of the casing material by less than half compared to the most advantageous value for the integrated foam of polyurethane, the mass moment of inertia of the steering wheel while maintaining the same material consumption of the framework structure of the steering wheel Can be significantly reduced. This is because the material processed according to the invention has the largest proportion of it disposed in the steering wheel ring. Reducing the weight of the steering wheel is also in line with the general economic objective of reducing the weight of the vehicle structure. In addition, the materials used can be recycled without high processing costs, so their use is also welcome from an ecological point of view. Embodiments 2 to 8 of the present application describe various advantageous alternatives, all based on the basic idea of the invention. According to these alternatives, the steering wheel cover is made from a foamable thermomeric plastic. The practice of these embodiments often results in a dense surface that is easily and sufficiently abrasion-resistant and yet has a satisfactory tactile feel, which, of course, can be applied in whole or in part in a manner known per se to leather, wood laminates. Alternatively, it can be covered with a cover layer of a material equivalent thereto. For mass production, a suitable plastic cover layer can also be applied in a second operating step, as described in embodiments 9 to 13 of the present application. The above makes it possible on the one hand to manufacture steering wheels with particularly low mass moments of inertia, and on the other hand to make it possible to improve ordinary surfaces in all respects without any functional restrictions. Is shown.
Claims (1)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19719321A DE19719321C2 (en) | 1997-05-08 | 1997-05-08 | Manufacture of a light steering wheel |
| DE19719321.8 | 1997-05-08 | ||
| PCT/EP1998/002669 WO1998050215A1 (en) | 1997-05-08 | 1998-05-06 | Method for producing a lightweight steering wheel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000514743A true JP2000514743A (en) | 2000-11-07 |
Family
ID=7828909
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10547735A Pending JP2000514743A (en) | 1997-05-08 | 1998-05-06 | Manufacturing method of lightweight steering wheel |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0912314A1 (en) |
| JP (1) | JP2000514743A (en) |
| KR (1) | KR20000022405A (en) |
| BR (1) | BR9804887A (en) |
| DE (1) | DE19719321C2 (en) |
| WO (1) | WO1998050215A1 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6386579B1 (en) * | 1999-07-22 | 2002-05-14 | Breed Automotive Technology, Inc. | Steering wheel |
| DE10238517A1 (en) * | 2002-08-21 | 2003-10-09 | Ticona Gmbh | Flat or round plastic component for hydraulic control equipment in automatic transmissions is produced to high specified tolerance levels |
| US20040076816A1 (en) * | 2002-10-22 | 2004-04-22 | Trw Vehicle Safety Systems Inc. | Wrapped steering wheel free of adhesive interface |
| DE20217918U1 (en) | 2002-11-19 | 2003-02-20 | Brose Fahrzeugteile GmbH & Co. Kommanditgesellschaft, Coburg, 96450 Coburg | Adjustment device of a motor vehicle |
| CN115139442B (en) * | 2022-05-27 | 2024-06-25 | 均胜汽车安全系统(安徽)有限公司 | Steering wheel foam manufacturing method and steering wheel |
Family Cites Families (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1669663A1 (en) * | 1966-09-09 | 1972-03-02 | Basf Ag | Process for the production of molded articles from foam-shaped ethylene copolymers |
| DE1704514A1 (en) * | 1967-12-12 | 1971-05-27 | Basf Ag | Process for the production of foam-shaped shapes from olefin polymers |
| GB1329094A (en) * | 1969-12-22 | 1973-09-05 | Profile Expanded Plastics Ltd | Moulding articles of expandable thermoplastics material with a reinforcement |
| FR2406516A1 (en) * | 1977-10-19 | 1979-05-18 | Isobox Barbier Sa | DEVICE AND METHOD FOR MANUFACTURING THIN-WALL OBJECTS IN EXPANDED PLASTIC MATERIAL |
| JPS5943492B2 (en) * | 1981-08-05 | 1984-10-22 | 日本スチレンペ−パ−株式会社 | Manufacturing method of polypropylene resin foam molding |
| JPS59179321A (en) * | 1983-03-30 | 1984-10-11 | Nissan Motor Co Ltd | Product made of foamed plastic |
| DE3330826A1 (en) * | 1983-08-26 | 1985-03-14 | Basf Ag, 6700 Ludwigshafen | METHOD FOR PRODUCING FOAM MOLDED BODIES FROM POLYOLEFINES |
| FR2592610B3 (en) * | 1986-01-03 | 1988-04-08 | Usine Applic Polystyrene Expan | PROCESS AND DEVICE FOR THE MANUFACTURE OF A PRE-EXPANDED SYNTHETIC THERMOPLASTIC SYNTHETIC MATERIAL PART. |
| US4698191A (en) * | 1986-01-31 | 1987-10-06 | Mitsubishi Yuka Badische Co., Ltd. | Methods of producing molded products from foamed polypropylene particles |
| DE3842846A1 (en) * | 1988-12-20 | 1990-06-21 | Frigolit Gmbh | Process for the production of polyolefin sandwich mouldings |
| WO1990008642A1 (en) * | 1989-02-01 | 1990-08-09 | Adfoam Pty. Limited | Method and apparatus for manufacturing articles from expandible thermo-plastic materials |
| EP0477476B1 (en) * | 1990-09-26 | 1996-02-21 | Alkor Gmbh Kunststoffe | Method and apparatus for producing moulded articles |
| DE4030478C2 (en) * | 1990-09-26 | 1999-12-16 | Alkor Gmbh | Mfg. mouldings and objects for prodn. of vehicle inner linings, etc. - by forming 2nd form corresp. to form or profile of 1st produced form, closing moulding with lid and applying plastic particles, etc. |
| DE4036563A1 (en) * | 1990-11-16 | 1992-05-21 | Huels Chemische Werke Ag | METHOD FOR PRODUCING FOAM BODIES |
| DE4040908A1 (en) * | 1990-12-20 | 1992-06-25 | Basf Ag | FOAM MOLDED BODY WITH DIFFERENT SEALING AREAS AND METHOD AND MOLDING TOOL FOR THEIR PRODUCTION |
| DE4308764A1 (en) * | 1993-03-19 | 1994-09-22 | Basf Ag | Particle-foam mouldings based on olefin polymers with a compacted, smooth outer skin and process for their production |
| JP2982564B2 (en) * | 1993-06-19 | 1999-11-22 | 豊田合成株式会社 | Method of forming integral skin foam |
| DE9312247U1 (en) * | 1993-08-17 | 1993-10-28 | E. Dittrich KG "Schlüssel"-Erzeugnisse, 28307 Bremen | Molding for operating parts or the interior trim of motor vehicles |
| DE9313635U1 (en) * | 1993-08-17 | 1993-11-11 | E. Dittrich KG "Schlüssel"-Erzeugnisse, 28307 Bremen | Molding for operating parts or the interior trim of motor vehicles |
-
1997
- 1997-05-08 DE DE19719321A patent/DE19719321C2/en not_active Expired - Fee Related
-
1998
- 1998-05-06 BR BR9804887-2A patent/BR9804887A/en not_active IP Right Cessation
- 1998-05-06 WO PCT/EP1998/002669 patent/WO1998050215A1/en not_active Ceased
- 1998-05-06 JP JP10547735A patent/JP2000514743A/en active Pending
- 1998-05-06 KR KR1019980710837A patent/KR20000022405A/en not_active Withdrawn
- 1998-05-06 EP EP98929284A patent/EP0912314A1/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| BR9804887A (en) | 1999-08-31 |
| DE19719321A1 (en) | 1998-11-12 |
| KR20000022405A (en) | 2000-04-25 |
| EP0912314A1 (en) | 1999-05-06 |
| DE19719321C2 (en) | 2000-12-14 |
| WO1998050215A1 (en) | 1998-11-12 |
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