WO1996035895A1 - Protective bellows - Google Patents
Protective bellows Download PDFInfo
- Publication number
- WO1996035895A1 WO1996035895A1 PCT/GB1996/000881 GB9600881W WO9635895A1 WO 1996035895 A1 WO1996035895 A1 WO 1996035895A1 GB 9600881 W GB9600881 W GB 9600881W WO 9635895 A1 WO9635895 A1 WO 9635895A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- bellows
- turns
- type
- fixing collar
- dimensional stability
- Prior art date
Links
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
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J3/00—Diaphragms; Bellows; Bellows pistons
- F16J3/04—Bellows
- F16J3/041—Non-metallic bellows
- F16J3/042—Fastening details
Definitions
- the invention relates to a protective bellows made of elastomeric material and comprising at least one fixing collar and a plurality of bellows turns extending from the fixing collar to an opposite longitudinal end of the bellows, the bellows turns
- bellows being integrally connected along its length but being of a plurality of different types arranged longitudinally of the bellows with respect to each other.
- Such a bellows is known from EP-A-0 487 840.
- all the bellows turns are made from a thermoplastic elastomer of one type and the fixing collar is made from an elastomer of a different type.
- the characteristics of the material of the bellows turn are substantially the same along the length of the body of the bellows and this may not be suitable
- the invention aims to deal with this problem.
- the known protective bellows is characterised in that at least one of the bellows turns is of a first one of the types of elastomeric material and at least another of the bellows turns is of a second one of the
- Figure 1 is a longitudinal section through one of the protective bellows, for protecting a universal joint in a vehicle transmission system
- Figure 2 is a longitudinal half-section through another form of the bellows, for protecting the steering mechanism of a vehicle.
- the bellows 4 comprises a plurality of bellows turns 5 having peaks 5A and troughs 5B and which extend between a large diameter fixing collar 6 and a small diameter fixing collar 8.
- the large diameter fixing collar 6 is clamped around the casing 10 of the transmission joint.
- the drive shaft 12 emerges from the casing 10 and the small diameter fixing collar 8 is mounted around it.
- Suitable clamping rings or other fixtures may be used to secure the fixing collars 6 and
- the bellows 4 is advantageously produced from elastomeric
- thermoplastic material such as by blow-moulding.
- the material from which the bellows is moulded has non-homogenous physical characteristics, although the material of the complete bellows is integral throughout. In this way, therefore, different parts of the bellows can be arranged to have particular physical characteristics according to the respective functions which they have to perform.
- the material of the bellows turns 5 is of a first type selected to have particular characteristics suited to their position close to the universal joint 10.
- the bellows turns 5 are made from a second type of thermoplastic elastomer, this material being suited to the characteristics required of the bellows turns over this portion of the bellows which are spaced from the universal joint 10 and are of reduced diameter and may need to be stiffer so as
- the fixing collars 6 and 8 can be produced from a third type of thermoplastic material which is selected to have characteristics suited to the functions of ease of assembly and good sealing. This material must be such that it can be relatively easily stretched, so that the collars 6,8 can be placed over the outside of the casing 10, or the outside of the shaft 12, as the case may be. However, it must also then resile so as to grip and seal around the casing 10 or the shaft
- the material must be selected so that this good gripping and sealing function is maintained throughout the life of the bellows.
- the material of the bellows turns must have good dimensional flexibility and must enable the bellows turns to flex easily through large angles of deflection when the axis of the shaft 12 becomes angularly offset as permitted by the universal joint. At the same time, though, the material of the bellows turns 5 must be such that it is not damaged by contact wear or by the heat generated by such flexing. By constructing the bellows from different types of material in this way, each of the materials is selected for optimum
- the bellows 14 in Figure 2 is for protecting the rack of a vehicle steering mechanism. It comprises bellows turns 16 having
- the fixing collar 18 attaches around the outside of the casing 28 of the steering mechanism. From the latter, the steering rod 30 extends to a casing 32.
- Casing 32 encloses a universal joint connected to a rod end 34, the joint permitting the rod end 34 to articulate angularly with respet to the axis of the rod 30.
- the rod end 34 extends through the small diameter fixing collar 24, the latter gripping around the rod end 34.
- the large diameter fixing collar 18 may be provided with a shaped inwardly directed shoulder for engaging a groove in the outside of the casing 24 so as to secure it to the casing. Other fixing means may be used instead.
- the small diameter fixing collar 24 may be secured around the rod end 34 by means of a fixing clamp (not shown) or it may simply grip the rod end resiliently.
- the rod 30 moves axially and the rod end 34 moves angularly with respect to the rod 30, this angular movement being permitted by the universal joint in the casing 32.
- the bellows turns 16 accommodate the axial movement of the rod 30.
- the bellows turns 22 flex correspondingly.
- the skirt portion 20 ensures that the bellows turns 16 are unaffected by this angular movement .
- the bellows is advantageously produced from elastomeric thermoplastic material such as by blow-moulding extrusion.
- the bellows is integrally moulded from materials having different physical characteristics which are respectively suited to the different functions to be carried out by different parts of the bellows.
- the bellows turns 16 are constructed from material of a first type which has to be capable of axial movement and to have sufficient strength and dimensional stability to maintain this capability throughout the life of the bellows and to maintain clearance around the rod 30. It also has to be capable of withstanding heat generated by the axial movement.
- the material of the bellows turns 22 is of a second type selected
- the material of the fixing collar 18 may be material of a third type which is selected so as to be flexible and resilient. This enables it to be stretched relatively easily so as to enable it to be fixed around the outside of the casing 28, but it must also be capable of resiling so as to seal and grip against the outside of the casing and to maintain this characteristic throughout the life of the bellows.
- the material for the fixing collar 24 may also be of the third type or of a different type.
- the rod end 34 may have an enlarged shoulder 38. Therefore, the material of the collar 24 has to be capable of being stretched over this shoulder 38 during assembly.
- skirt portion 20 is constructed from material of a further type which is arranged to be relatively rigid so as to locate itself securely on the casing 32.
- each of the bellows 4 and 14 can be integrally moulded but can nevertheless be constructed from different materials each selected to be the most effective and economic for the particular functions to be performed by the different parts of the bellows.
- the different types of elastomeric material produced by the blow-moulding or other process must be such that they are chemically compatible with each other so that the bellows is produced as an integral whole. Over each region where two different types of the material meet, the different
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Diaphragms And Bellows (AREA)
- Sealing Devices (AREA)
Abstract
A protective bellows (4), such as for protecting the transmission of a motor vehicle, comprises bellows turns (5) extending between large and small diameter fixing collars (6, 8). The large diameter fixing collar (6) is secured around the casing (10) of a universal jointy. The small diameter fixing collar (8) is secured around the outside surface of the drive shaft (12) of the transmission. The bellows is preferably moulded from elastomeric thermoplastic material. Although the bellows is integrally moulded, the materials of different sections (A, B) of the bellows turns (5) are selected so as to be different and to have the required characteristics for the respective parts. The material for the fixing collars (6, 8) may be material of a further type which is easily stretched so as to enable the fixing collars to be easily mounted in position, but also to be resilient so as to provide good gripping and sealing and to maintain this throughout the life of the bellows.
Description
PROTECTIVE BELLOWS
The invention relates to a protective bellows made of elastomeric material and comprising at least one fixing collar and a plurality of bellows turns extending from the fixing collar to an opposite longitudinal end of the bellows, the bellows turns
comprising peaks and troughs, the elastomeric material of the
bellows being integrally connected along its length but being of a plurality of different types arranged longitudinally of the bellows with respect to each other.
Such a bellows is known from EP-A-0 487 840. In this bellows, all the bellows turns are made from a thermoplastic elastomer of one type and the fixing collar is made from an elastomer of a different type. With such a bellows, the characteristics of the material of the bellows turn are substantially the same along the length of the body of the bellows and this may not be suitable
for certain applications. The invention aims to deal with this problem.
According to the invention, therefore, the known protective bellows is characterised in that at least one of the bellows
turns is of a first one of the types of elastomeric material and at least another of the bellows turns is of a second one of the
types of elastomeric material.
In this way, different longitudinally arranged portions of the bellows turns can be given different characteristics to suit their particular purposes.
Protective bellows embodying the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings in which:
Figure 1 is a longitudinal section through one of the protective bellows, for protecting a universal joint in a vehicle transmission system; and
Figure 2 is a longitudinal half-section through another form of the bellows, for protecting the steering mechanism of a vehicle.
As shown in Figure 1, the bellows 4 comprises a plurality of bellows turns 5 having peaks 5A and troughs 5B and which extend between a large diameter fixing collar 6 and a small diameter fixing collar 8. In use, the large diameter fixing collar 6 is
clamped around the casing 10 of the transmission joint. The drive shaft 12 emerges from the casing 10 and the small diameter fixing collar 8 is mounted around it. Suitable clamping rings or other fixtures may be used to secure the fixing collars 6 and
8 in position.
The bellows 4 is advantageously produced from elastomeric
thermoplastic material such as by blow-moulding. In accordance
with a feature of the bellows being described, however, the material from which the bellows is moulded has non-homogenous physical characteristics, although the material of the complete bellows is integral throughout. In this way, therefore, different parts of the bellows can be arranged to have particular physical characteristics according to the respective functions which they have to perform.
Therefore, over a region A, the material of the bellows turns 5 is of a first type selected to have particular characteristics suited to their position close to the universal joint 10. Over the region B, though, the bellows turns 5 are made from a second type of thermoplastic elastomer, this material being suited to the characteristics required of the bellows turns over this portion of the bellows which are spaced from the universal joint
10 and are of reduced diameter and may need to be stiffer so as
not to come into contact with the shaft 12.
In addition, in the bellows 4 the fixing collars 6 and 8 can be produced from a third type of thermoplastic material which is selected to have characteristics suited to the functions of ease of assembly and good sealing. This material must be such that it can be relatively easily stretched, so that the collars 6,8 can be placed over the outside of the casing 10, or the outside of the shaft 12, as the case may be. However, it must also then resile so as to grip and seal around the casing 10 or the shaft
12. Furthermore, the material must be selected so that this good gripping and sealing function is maintained throughout the life of the bellows.
The material of the bellows turns must have good dimensional flexibility and must enable the bellows turns to flex easily through large angles of deflection when the axis of the shaft 12 becomes angularly offset as permitted by the universal joint. At the same time, though, the material of the bellows turns 5 must be such that it is not damaged by contact wear or by the heat generated by such flexing.
By constructing the bellows from different types of material in this way, each of the materials is selected for optimum
performance for the particular functions which the respective parts of the bellows have to carry out.
The bellows 14 in Figure 2 is for protecting the rack of a vehicle steering mechanism. It comprises bellows turns 16 having
peaks 16A and troughs 16B. The bellows turns 16 extend between
a relatively large diameter fixing collar 18 to a generally cylindrical skirt portion 20. From the latter, further bellows turns 22.
As shown in Figure 2, the fixing collar 18 attaches around the outside of the casing 28 of the steering mechanism. From the latter, the steering rod 30 extends to a casing 32. Casing 32 encloses a universal joint connected to a rod end 34, the joint permitting the rod end 34 to articulate angularly with respet to the axis of the rod 30. The rod end 34 extends through the small diameter fixing collar 24, the latter gripping around the rod end 34.
The large diameter fixing collar 18 may be provided with a shaped inwardly directed shoulder for engaging a groove in the outside
of the casing 24 so as to secure it to the casing. Other fixing means may be used instead. At the opposite end of the bellows, the small diameter fixing collar 24 may be secured around the rod end 34 by means of a fixing clamp (not shown) or it may simply grip the rod end resiliently.
During operation of the steering mechanism, the rod 30 moves axially and the rod end 34 moves angularly with respect to the rod 30, this angular movement being permitted by the universal joint in the casing 32. The bellows turns 16 accommodate the axial movement of the rod 30. During the angular movement of the rod end 34, the bellows turns 22 flex correspondingly. The skirt portion 20 ensures that the bellows turns 16 are unaffected by this angular movement .
Again, the bellows is advantageously produced from elastomeric thermoplastic material such as by blow-moulding extrusion. In accordance with a feature of the bellows being described, the bellows is integrally moulded from materials having different physical characteristics which are respectively suited to the different functions to be carried out by different parts of the bellows.
Thus, the bellows turns 16 are constructed from material of a first type which has to be capable of axial movement and to have sufficient strength and dimensional stability to maintain this capability throughout the life of the bellows and to maintain clearance around the rod 30. It also has to be capable of withstanding heat generated by the axial movement.
The material of the bellows turns 22 is of a second type selected
so as to be suitable for the angular movement which this part of the bellows is to undergo. Again, it needs to have good dimensional stability and to be able to withstand the heat generated by the angular movement.
Furthermore, the material of the fixing collar 18 may be material of a third type which is selected so as to be flexible and resilient. This enables it to be stretched relatively easily so as to enable it to be fixed around the outside of the casing 28, but it must also be capable of resiling so as to seal and grip against the outside of the casing and to maintain this characteristic throughout the life of the bellows. The material for the fixing collar 24 may also be of the third type or of a different type. The rod end 34 may have an enlarged shoulder 38. Therefore, the material of the collar 24 has to be capable of
being stretched over this shoulder 38 during assembly.
Finally, the skirt portion 20 is constructed from material of a further type which is arranged to be relatively rigid so as to locate itself securely on the casing 32.
In this way, each of the bellows 4 and 14 can be integrally moulded but can nevertheless be constructed from different materials each selected to be the most effective and economic for the particular functions to be performed by the different parts of the bellows.
In the embodiments described, the different types of elastomeric material produced by the blow-moulding or other process must be such that they are chemically compatible with each other so that the bellows is produced as an integral whole. Over each region where two different types of the material meet, the different
types of material will merge together at the join.
Claims
1. A protective bellows made of elastomeric material and comprising at least one fixing collar (6,8,-18,24) and a plurality of bellows turns (5,-16,22) extending from the fixing collar
(6, 8,-18,24) to an opposite longitudinal end of the bellows, the
bellows turns (5,-16, 22) comprising peaks (5A;16A) and troughs
(5B;16B) , the elastomeric material of the bellows being integrally connected along its length but being of a plurality of different types arranged longitudinally of the bellows with respect to each other, characterised in that at least one of the bellows turns (A;16) is of a first one of the' types of elastomeric material and at least another of the bellows turns
(B;22) is of a second one of the types of elastomeric material.
2. A bellows according to claim 1, characterised in that the fixing collar (6, 8,-18,24) is made of a third one of the types of elastomeric material.
3. A bellows according to claim 2, characterised by a fixing
collar (6, 8,-18, 24) at the opposite end of the bellows, the material of this fixing collar being of a fourth one of the said types .
4. A bellows according to claim 2 or 3, characterised in that the said material of the or each fixing collar (6, 8,-18,24) is material which is easily stretched and is resilient and capable of maintaining its resilience over substantially the life of the
bellows.
5. A bellows according to any preceding claim, characterised in that the material of the first type is material having good dimensional stability and heat resistance and capable of withstanding axial movement of the bellows.
6. A bellows according to any preceding claim, characterised in that the material of the second type is material having good dimensional stability and heat resistance and capable of withstanding angular movement of the bellows.
7. A bellows according to any one of claims 1 to 4, characterised in that a first plurality of the bellows turns (A, 16) are of the said first type of material and a second plurality of the bellows turns (B,22) are of the said second type of material.
8. A bellows according to claim 7, characterised in that the first and second pluralities of bellows turns (16,22) are integrally connected by a generally cylindrical skirt portion (20) of the bellows.
9. A bellows according to claim 8, characterised in that the material of the first type is material having good dimensional
stability and heat resistance and capable of withstanding axial
movement of the bellows.
10. A bellows according to claim 9, characterised in that the material of the second type is material having good dimensional stability and heat resistance and capable of withstanding angular
movement of the bellows.
11. A bellows according to any one of claims 8 to 10, characterised in that the skirt portion (20) is made of a further type of the elastomeric material.
12. A bellows according to claim 11, characterised in that the material of the said further type is relatively rigid with good dimensional stability.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9509355.5 | 1995-05-09 | ||
GBGB9509355.5A GB9509355D0 (en) | 1995-05-09 | 1995-05-09 | Protective bellows |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996035895A1 true WO1996035895A1 (en) | 1996-11-14 |
Family
ID=10774177
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB1996/000881 WO1996035895A1 (en) | 1995-05-09 | 1996-04-10 | Protective bellows |
Country Status (2)
Country | Link |
---|---|
GB (1) | GB9509355D0 (en) |
WO (1) | WO1996035895A1 (en) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2388097A (en) * | 1943-11-13 | 1945-10-30 | Russell J Turner | Rubber protector |
DE2954186C2 (en) * | 1979-08-25 | 1984-12-13 | Fa. Carl Freudenberg, 6940 Weinheim | Arrangement for modifying the strength of a plastic part by irradiation |
FR2596693A1 (en) * | 1986-04-04 | 1987-10-09 | Ouest Cie | Process and device for injection blow-moulding of hollow bodies having two thermoplastic components and hollow bodies thus obtained |
JPH02120574A (en) * | 1988-10-31 | 1990-05-08 | Toyoda Gosei Co Ltd | Manufacture of resin-made dust boot |
EP0487840A1 (en) * | 1990-11-24 | 1992-06-03 | Firma Carl Freudenberg | Bellows of thermoplastic elastomer |
-
1995
- 1995-05-09 GB GBGB9509355.5A patent/GB9509355D0/en active Pending
-
1996
- 1996-04-10 WO PCT/GB1996/000881 patent/WO1996035895A1/en active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2388097A (en) * | 1943-11-13 | 1945-10-30 | Russell J Turner | Rubber protector |
DE2954186C2 (en) * | 1979-08-25 | 1984-12-13 | Fa. Carl Freudenberg, 6940 Weinheim | Arrangement for modifying the strength of a plastic part by irradiation |
FR2596693A1 (en) * | 1986-04-04 | 1987-10-09 | Ouest Cie | Process and device for injection blow-moulding of hollow bodies having two thermoplastic components and hollow bodies thus obtained |
JPH02120574A (en) * | 1988-10-31 | 1990-05-08 | Toyoda Gosei Co Ltd | Manufacture of resin-made dust boot |
EP0487840A1 (en) * | 1990-11-24 | 1992-06-03 | Firma Carl Freudenberg | Bellows of thermoplastic elastomer |
Non-Patent Citations (1)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 14, no. 351 (M - 1003) 30 July 1990 (1990-07-30) * |
Also Published As
Publication number | Publication date |
---|---|
GB9509355D0 (en) | 1995-06-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CA2009915A1 (en) | Boot assembly for constant velocity joint | |
EP1027552B1 (en) | Variable stiffness bellows | |
US5145191A (en) | Heat-resistant protective cover for a drive axle joint seal | |
EP0611149A1 (en) | Slipper bushing | |
EP0403163B1 (en) | Protective gaiters for joints | |
GB2136514A (en) | Arrangement for securing bellows on a cylindrical body | |
EP0525410B1 (en) | Mechanical face seals | |
US4602808A (en) | Protective routing sleeve for hose assembly | |
EP0658469A1 (en) | Ball joint assembly | |
CA1276793C (en) | Retention of boot on cv joint assembly | |
EP1002469B1 (en) | Glove of rubber or the like | |
US5879238A (en) | Protective bellows | |
US5213002A (en) | Bearing system for a gear shift lever | |
GB2262142A (en) | Protective bellows | |
US20030062722A1 (en) | Hose line with a connection sleeve | |
EP0359253A2 (en) | Constant volume protective boot | |
EP0226845B1 (en) | Single component seal | |
WO1996035895A1 (en) | Protective bellows | |
CA1302101C (en) | Flexible boot for universal joints | |
GB2300678A (en) | Protective bellows | |
JP4472335B2 (en) | Bellows boots for constant velocity joints | |
EP0669476A1 (en) | Protective bellows | |
EP0606199B1 (en) | External convoluted high speed constant velocity joint boot | |
US6354953B1 (en) | Bearing ring for supporting a protective device | |
WO1994020764A1 (en) | A mechanical control cable system having an umbrella seal |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): BR CN CZ JP KR MX US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
122 | Ep: pct application non-entry in european phase |