US4224276A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for manufacturing closed hollow bodies in elastomeric material
Assignee: Industrie Pirelli SpA
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Filing: 1978-07-13
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Granted: 1980-09-23
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Expires: 1998-07-13
Abstract
Abstract A process and a device are disclosed for forming a tennis ball which comprises the formation of two semispherical bowls in crude elastomeric material each having on its border a structural shape that is deformed by compression when the two semispherical bowls are pressed one against the other while a depressurization is effected in the joining zone of the two semispherical bowls on the outside of them.
Inventors
- 👤 Achille Gallizia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:34
CPC Classifications
B; B29; B29D; B29D22/00; B29D22/04; B29C; B29C45/00; B29C45/0053; B29C45/006; B29C65/00; B29C66/00; B29C66/01; B29C66/05; B29C66/10; B29C66/11; B29C66/114; B29C66/1142; B29C66/50; B29C66/51; B29C66/54; B29C66/70; B29C66/71; B29C2045/0072; B29K; B29K2021/00; B29L; B29L2031/00; B29L2031/54
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
205 words
A process for manufacturing a closed hollow body having an elastomeric wall comprising the steps of: shaping raw elastomeric material into complementary parts of a closed hollow body having an open side with an elastomeric wall therearound, said complementary parts having a tapered edge tapering towards the outside, butt-end joining said tapered edges of the complementary parts by partially pressing together said tapered edges starting with the part of said edges which is innermost with respect to the hollow cavity of the closed hollow body until parts of the surfaces of the tapered edges disposed between their internal and external borders are also in contact while maintaining a constant pressure between said contacting tapered edges, reducing the pressure in the space surrounding the butt-end joint between said complementary parts whereby material is moved from the inside towards the outside of the butt-end joint and gas bubble formation in said butt-end joint is prevented, increasing the pressure which forces the tapered edges of the complementary parts together while maintaining a reduced pressure around the butt-end joint until the external border of said tapered edges of said complementary parts of the hollow body are brought into contact, and vulcanizing the elastomeric material of the closed hollow body.
Claim 2
Dependent Claim
205 words
A process for manufacturing a closed hollow body having an elastomeric wall comprising the steps of: shaping raw elastomeric material into complementary parts of a closed hollow body having an open side with an elastomeric wall therearound, said complementary parts having a tapered edge tapering towards the outside, butt-end joining said tapered edges of the complementary parts by partially pressing together said tapered edges starting with the part of said edges which is innermost with respect to the hollow cavity of the closed hollow body until parts of the surfaces of the tapered edges disposed between their internal and external borders are also in contact while maintaining a constant pressure between said contacting tapered edges, reducing the pressure in the space surrounding the butt-end joint between said complementary parts whereby material is moved from the inside towards the outside of the butt-end joint and gas bubble formation in said butt-end joint is prevented, increasing the pressure which forces the tapered edges of the complementary parts together while maintaining a reduced pressure around the butt-end joint until the external border of said tapered edges of said complementary parts of the hollow body are brought into contact, and vulcanizing the elastomeric material of the closed hollow body.
Claim 3
Dependent Claim
32 words
The process of claim 1 comprising the step of pressurizing the hollow body while the complementary parts constituting it come into contact with each other during the compression of the tapered edges.
Claim 4
Dependent Claim
39 words
A process according to claim 2 comprising before the step of shaping the raw elastomeric material into the complementary parts of said hollow body, the step of degasifying the raw elastomeric material to be formed into said complementary parts.
Claim 5
Dependent Claim
203 words
A process for making a closed hollow spherical elastomeric article which comprises: (a) shaping raw elastomeric material into complementary parts of a closed hollow spherical article having open sides with elastomeric walls therearound, said complementary parts having tapered edges which taper towards the outside, (b) butt-end joining said tapered edges of the complementary parts by pressing together said tapered edges starting with the parts of said edges which are innermost with respect to the hollow cavity of the closed spherical article and maintaining a constant pressure between said contacting tapered edges until the surfaces between the internal and external borders of the edges are also in contact with each other, (c) reducing the pressure in the space surrounding the butt-end joint between said complementary parts whereby material is moved from the inside towards the outside of the butt-end joint and gas bubble formation in said butt-end joint is prevented, (d) increasing the pressure which forces the tapered edges of the complementary parts together while maintaining a reduced pressure around the butt-end joint until the external borders of said tapered edges of said complementary parts of the hollow article are brought into contact, and, (e) vulcanizing the elastomeric material of the closed hollow article.
Claim 6
Dependent Claim
203 words
A process for making a closed hollow spherical elastomeric article which comprises: (a) shaping raw elastomeric material into complementary parts of a closed hollow spherical article having open sides with elastomeric walls therearound, said complementary parts having tapered edges which taper towards the outside, (b) butt-end joining said tapered edges of the complementary parts by pressing together said tapered edges starting with the parts of said edges which are innermost with respect to the hollow cavity of the closed spherical article and maintaining a constant pressure between said contacting tapered edges until the surfaces between the internal and external borders of the edges are also in contact with each other, (c) reducing the pressure in the space surrounding the butt-end joint between said complementary parts whereby material is moved from the inside towards the outside of the butt-end joint and gas bubble formation in said butt-end joint is prevented, (d) increasing the pressure which forces the tapered edges of the complementary parts together while maintaining a reduced pressure around the butt-end joint until the external borders of said tapered edges of said complementary parts of the hollow article are brought into contact, and, (e) vulcanizing the elastomeric material of the closed hollow article.
Claim 7
Dependent Claim
16 words
The process of claim 4 wherein the said closed hollow spherical article is a tennis ball.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-23 | 1984-03-24 | 1984-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-23 | 1988-03-24 | 1988-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-23 | 1992-03-24 | 1992-09-23 | $7700.00 | Window Closed / Lapsed |