DE2904363A1 - FLEXIBLE ELASTIC SEALING SHOE - Google Patents

Description

DlPL-ING. HORST RSSE DIPL-ING. PETER KOSEL ^{PATENT LAWYERS}

3353 Bad Gandershelm, Q February 5, 1979

P.O. Box 129

Hohenhölen S.

Telephone: (05382) 2842

Telegram address: Siedpatent Badgandershelm

Our file no.

Garlock Ine 2620/24

Patent application dated February 05, 1979

Garlock Ine

1250 Midtown Tower, Rochester, New York V. St. A

Flexible elastic sealing shoe

The invention relates to a flexible elongated sealing shoe made of elastomeric material for sealing a cylinder and a retractable piston in the cylinder, which piston has a groove on its peripheral wall for receiving a narrow end of the sealing shoe and which cylinder has a bore for receiving a wider end of the sealing shoe, the piston and the cylinder being annular Having space between the bore wall and the piston wall for accommodating the folds of the shoe, and wherein the shoe has a metal shell at one end that can be inserted into the bore and an elastomeric sleeve glued to the metal shell.

Such a sealing shoe is used in particular in the annular space between a piston and a cylinder of a disc brake

909832/0752

290A363

arrangement used to keep the piston and cylinder chambers from contamination protect from dust and water.

Disc brake sealing shoes or dirt seals are known and are used in automotive engineering. However, the known type of elastic rubber sealing shoe that is commonly used is one such shoe which has a uniformly thin flexible wall injected into a folded or bellows-like, contracted form and then pulled into an elongated shape during operation for use in a stain resistant configuration, one end being received in a cylinder bore or cylinder recess and the other end being received in a piston groove. In the interest of lower space consumption and low weight the annular space between the piston and the bore must be kept as narrow as possible. For example, the piston outside diameter 45mm and the groove on the cylinder or the bore on the cylinder to accommodate the shoe is 58.3 mm. It must also be possible be that the shoe expand to a length of about 30 mm and can be compressed to a total height of about 11.5 mm must when the piston is retracted to change the brake pads. The resulting tightness of the annular space between the receiving wall of the bore and the piston leads to the great difficulty to inject a shoe of a bellows shape, its fold-like folds having sharp bends. It is required that the usual shoe can flex and roll into the annular space upon retraction of the piston. The sharp bends in the bellows walls in known shoes ensure that the shoe in an uneven, jerky manner during the pulling in and the Expansion works. One known shoe which is of the bellows type is described, for example, in US Pat. No. 3,998,466.

90 98 32/0752

The object of the invention is to provide a sealing shoe of the type mentioned at the beginning Kind of to create compared to the well-known sealing shoes in a steady and non-jerky manner during entry and extending the piston of a piston-cylinder assembly operates.

This object is achieved according to the invention in that the elongated, unfolded sleeve made of elastomeric material at least seven different injected wall sections of different Thickness with a sealing strip, an upper shoe wall, an upper bending wall, a stabilizing wall, an outwardly widening, frustoconical i gene rolling wall, a lower bending and rolling wall and a cylindrical sealing end, and that the sealing strip and the upper shoe wall are shaped to extend radially inwardly from the stabilizing wall and thus over the

upper bending wall are connected, and that the lower bending and rolling wall and the cylindrical sealing end formed radially with a larger diameter than the stabilizing wall and thus over the outwardly widening, frustoconical roll wall are connected.

This is an improved sealing shoe for use in the annular space between the cylinder and the piston Disc brake assembly created, wherein the sealing shoe is sprayed onto an annular metallic reinforcing shell and that as an integral, one-piece stretched, flexible elastomeric sealing shoe, which has a sleeve of a non-folded shape that has a Has a variety of different sections with a variety of different wall thicknesses. The sealing shoe has seven different sleeve sections that work together, in order to enable the sealing shoe when installed in a disc brake assembly to be bent into a folded shape which

-4-

909832/0752

into the annular space between the shoe and the piston wall Withdrawing the piston into the cylinder in the brake assembly, when the piston is withdrawn, fits the brake pads to replace. The elongated, unsheathed shape of the sleeve is for injection molding or compression molding when compared with the uniformly thin, pleated shape of the conventional sleeve from Bellows type compares which is difficult to inject. Furthermore the sealing shoe according to the invention "is at least as effective such as the known seals for sealing the piston from dirt and "water in a known manner. Furthermore, the new, fiction, contemporary Sealing shoe a smoothly retracting and expanding, flexible sleeve in which the various thicknesses of the various wall sections Improve the flexing and rolling of the shoe when in a folded shape or /. brought into its elongated form will.

Further advantageous refinements of the invention are set out in the subclaims refer to.

909832/0752

Based on the drawing, in which the embodiment of the invention is shown is, the invention and further advantageous embodiments and improvements and advantages are to be explained and described in more detail will.

It shows:

Fig. 1 is a partial sectional view of a known one

·. Uichtschuhs for a disc brake,

Fig. 2 is a partial sectional view of an invention

appropriate sealing shoe for a disc brake,

Fig. 3 is a partial cross section of a piston of a disk

benbremse with one end of the sealing shoe according to the invention in the extended position and held in a groove on the piston, and

Fig. 4 is a partial sectional view of a piston, a

Cylinder and the sealing shoe according to the invention, which shows the sealing shoe in a compressed, rolled-up position, with the piston is in the retracted position in the cylinder.

In Fig. 1 it can be seen that the known sealing shoe 2 is a thin-walled, bellows-like, rolled-up elastomeric sleeve 4, which is rolled up on a metallic reinforcement shell 6 is injected or injected. During use, the flexible bellows expand, and so does the elastomer of the bellows remains under tension during the reciprocation of the piston, that is, during the operation of the piston.

2 to 4 show a sealing shoe 8 according to the invention a one-piece, integral, molded, elongated, flexible elastic

-6-

909832/0752

stomeric sleeve 10 and an annular, metallic reinforcing shell 18 to which the elastomeric sleeve 10 is glued. The sealing shoe 8 is formed as a single unit that has an outer has cylindrical surface 9 which is designed so that it is in a bore 21 in a cylinder 20, a piston 19 adjacent, frictionally can be used (see Fig. 4).

The elastomeric sleeve 10 has characteristic portions, \ each cooperating with each other, the space between demKolbben 19 and to seal the cylinder 20 to prevent dirt and "water may enter the sliding portion of the piston. The seven sections of the sleeve act specifically together so that they allow the expanded sleeve to bend and roll and to converge into a rolled-up form which fits into an annular space between the piston 9 and the bore 21.

The seven sections of the elastomeric sleeve are best seen in FIG. The elastomer from which the sleeve is made can be made from any type of elastomer, which type is flexible at least at the maximum values of temperature where the disc brake assembly is normally used. The elastomer should also be mixed with brake fluids, Road salts, water and other expected contaminants must be tolerated. In general, any elastomer that is used for this can be used is used to make conventional, well known bellows-like seals such as rubber and synthetic elastomers are to the shoe according to the invention by means of known manufacturing and molding processes, such. B. Sprout casting or die casting, to manufacture.

The elastomeric sleeve 10 has, as a first section, a sealing strip section 11 at the end sealing the piston

-7-

909832/075 2

the sleeve. The strip portion 11 is formed so that it is elastic into an annular groove 23 in the peripheral wall of the piston 19 in the vicinity of an axially extending outer end wall 14 of the piston 19 can be used. The strip section 11 has an inner one Diameter sufficiently smaller than the outer diameter of the piston that the bar can be elastically stretched around it to be inserted into the groove 23 and to form a seal therewith, d. H. to achieve a sealing effect. The elastomeric sleeve

10 has as a second section an upper shoe wall 12, which has a substantially uniform wall thickness and one to the Adjoining bar, integral with this and radially outwards from this at an inclined angle to the plane of the strip section

11 has a running end. The wall section 12 or the shoe wall 12 has a radially outermost one, connected in one piece to an upper end of a third section of the sleeve 10 End, which end is an upper bending wall section 13. The upper Bending wall portion 13 has a lower, integrally connected to an upper end of a fourth portion of the sleeve end, which is a stabilizing wall section.

The stabilizing wall section 14 has a substantially uniformly thick wall, the thickness of which is greater than the wall thickness of the upper shoe wall section 12 _f and a length which is greater than the length of the upper shoe wall section 12. The upper flexible wall section 13 has a wall thickness that is thinner than that of either the upper shoe wall section 12 or the stabilizing wall section 14.

The stabilizing wall section 14 has an inner wall diameter, which is larger than the outer diameter of the piston but smaller than that of the end section 17 for the cylinder

-8th-

909832/075 2

seal (see below). The wall of the wall section 14 runs axially and parallel to the cylindrical wall of the metallic reinforcing shell 18 to which the sleeve 10 is glued.

The upper shoe wall section 12 is at an acute angle to the Wall of the wall section 14 arranged. The upper bending wall section

13 is curved and forms a connecting wall between the adjacent ones Ends of wall sections 12 and 14.

The elastomeric sleeve 10 has a fifth section after externally widening, frustoconical rolling wall section 15, the upper end of which is integral with the lower end of the wall section

14 and its lower end in one piece with a sixth section of the Sleeve 10, which is a lower flex and roll wall section 16. The wall section 16 has an inner diameter which is larger than the inner diameter of the stabilization wall section 14, and has an essentially uniform wall thickness, the thickness of which is less than the wall thickness of the wall section 14. The frustoconical roll wall section is approximately the same length or shorter than the stabilizing wall section 14 and the roll wall section 16 is shorter than the frustoconical rolling wall section 15 or the frustoconical rolling wall 15. The lower one End of the roll wall section 16 is integral with the upper end of the Seventh section of the elastomeric sleeve connected or injected with her, which is an end portion sealing the cylinder.

The inner diameter of the wall section 16 and of the cylinder sealing end portion 17 are sufficiently larger than the diameter of the piston 19 to provide an annular space to form that is sufficient to receive the stabilizing wall section 14 and the wall section 15 in a bent, rolled-up position, when the sealing shoe 18 is attached to a disc brake assembly and the piston 19 is retracted into the cylinder 20, such as it is the case when the disc brake pads have to be inserted or replaced. 909832/0752.,.

Fig. 4 shows the manner in which the elastomeric sleeve 10 in the area of the wall section 13 and the adjacent ends of the wall sections 14 and 15, the wall sections 15 and 16 and the wall section 16 or the end section for the cylinder seal 17 rolls and bends when the piston 19 is retracted into the cylinder 20 is. When the piston 20 reaches a fully extended position, the ledge portion 11 of the seal assumes the position shown in FIG Fig. 3 is shown, ■ where the bar is located in the groove 23 and the Wall section 12 extends radially outward, the wall section 13 from a position in which it assumes an acute angle (FIG. 4), is bent into such a position in which it assumes an obtuse angle (FIGS. 2 and 4 or FIG. 3). While the Piston, the seal works roughly as follows:

The upper shoe wall 12 exerts a downward and outward direction Force on the upper flexible wall section 13. This force is absorbed by the stabilizing wall section 14, whereby the sealing strip portion 10 is caused to roll within the sleeve, this allowing the upper shoe wall portion to expand 12 itself rotated into a position, as shown in FIG. 4. In a similar way the outwardly widening, frustoconical exercises Roll wall section 5 is directed downwards and outwards

C \ Ü £

Force on the lower bending and rolling wall section / Γ which then follows deformed on the outside, whereby it enables the Wp.ndabschnitt 15, itself to fold into a position as shown in FIG. 4 and roll into this position. Finally, the retraction of the piston ensures that the stabilizing wall portion 14 a downward ge directed force through the inverted wall portion 15 on the lower bending and rolling wall portion 16 exercises. Conversely, this step ensures that the wall section 16 roll itself into the rolled position according to FIG and can fold. The reversal steps or reversal movements of the

-10-

909832/0752

Wall sections 12 and 15 are independent of one another and can simultaneously or occur in any order.

If the disc brake pads are damaged, the sealing shoe moves from the shape or configuration according to FIG. 4 into that of FIG. 3. After the damaged brake pads have been replaced, the sealing shoe brought into the configuration according to FIG. 4 to repeat the cycle.

It goes without saying that the invention is not limited to the embodiments shown in the drawing, but there there are various variations and modifications that are still within the scope of protection.

Patent Attorneys Dfpl .-! Ng. Horst Rose Dipl.-Ing. Peter Kosel

909832/0752

Claims (13)

DIPL.-ING. HORST P.bSE DIiF L-ING. PETER KOSEL PATENT LAWYERS 3353 Bad Gandersheim, 0 3. ΡθΟ. "1979 P.O. Box 129 Hohenhöfen 5 Telephone: (05382) 2842 Telegram address: Siedpatent Badgandersheim Our file no. Garlock Ine patent application dated "3rd ΓδΟ. 1979 2620/24 Claims (1.! Flexible elongated sealing shoe made of elastomeric Material for sealing a cylinder and a piston that can be retracted into the cylinder, which piston has a groove on its peripheral wall for receiving a narrow end of the sealing shoe and which cylinder has a bore for receiving a wider end of the Has sealing shoe, the piston and the cylinder having an annular space between the bore wall and the piston wall for accommodating the folds of the shoe, and wherein the shoe has a metal shell on one insertable into the bore End and an elastomeric, glued to the metal shell sleeve, characterized in that the elongated, not folded sleeve made of elastomeric material at least seven different molded wall sections (11 to 17) of different Thickness with a sealing strip (11), an upper shoe wall (12), a upper bending wall (13), a stabilizing wall (14), one to the outside 909832/0752 widening, frustoconical rolling wall (15), a lower one Has bending and rolling wall (16) and a cylindrical sealing end (17), and that the sealing strip and the upper shoe wall are shaped so that they are radially inward from the stabilizing wall (14) extend and are connected to it via the upper bending wall (13), and that the lower bending and rolling wall (16) and the cylindrical sealing end formed radially with a larger diameter than the stabilizing wall (14) and thus over the outwardly widening, Truncated cone-shaped roll wall (15) are connected. 2. Sealing shoe according to claim 1, characterized in that the upper shoe wall (12) is injected so that it is at an acute angle is inclined towards the stabilizing wall (14). 3. Sealing shoe according to claim 2, characterized in that the cylinder - sealing end portion (17) is formed as a single element which has an outer cylindrical portion which is formed so that it directly into the bore (21) of the cylinder (20) can be used in the piston (19) and has an offset running radially inward, and that the cylindrical wall section has an inner diameter which is substantially greater than the outer diameter of the piston (19), and that the stabilizing Wall section (14) with its wall essentially in the axial direction parallel to the cylindrical wall section of the metal shell (18) with the stabilizing wall being essentially the same Having thickness. 4. Sealing shoe according to claim 3, characterized in that the upper shoe wall section (12) has a substantially uniform thickness which is less than that of the stabilizing wall section (14), and that the upper bending wall section (13) is curved and -3- 90 * 9832/0752 a curved connecting wall between the upper shoe wall portion (12) and the stabilizing wall section (14). 5. Sealing shoe according to claim 4, characterized in that the lower bending and rolling wall section (16) has an inner diameter which is greater than the inner diameter of the stabilizing wall section (14), and the lower bending and rolling wall section (16) has a substantially uniformly thick wall that is less than the wall thickness of the stabilizing Wall section that the frustoconical wall section (15) of the stabilizing wall section (14) towards the lower bending and rolling wall section (16 ^ extends that the frustoconical rolling wall section has a length less than that of the stabilizing Wall section (14) that the lower bending and rolling wall section (16) has a length which is less than that of the frustoconical Roll wall section (15) and that the lower bending and roll wall section (16) integrally at the upper end of the wall of the Cylinder - sealing end section (17) of the flexible elastomeric Sleeve is molded on. 6. Sealing shoe according to claim 5, characterized in that the inner diameter of the lower bending and rolling wall section (16) and the end portion (17) of the sleeve sealing the cylinder is sufficient are larger than the diameter of the piston (19) to form an annular space near the piston (19) so that this the stabilizing wall section (14) and the frustoconical wall section (15) Can accommodate the elastomeric sleeve in a bent, folded position when the piston is fully in the cylinder (20) is withdrawn. 7. Sealing shoe according to one of the preceding claims, characterized in that that the sealing shoe for sealing a piston-cylinder 909832/0752 " ⁴ " order of a disc brake assembly can be used. 8. DichtschJinach one of the preceding claims, characterized in that that the sealing strip section (f) at the end of the sleeve sealing the piston (19) has an inner diameter which is smaller is than the outer diameter of the piston and is designed so that it is resiliently in an annular groove (23) in the piston wall fits near the axially extending outer end (24) of the piston. 9. Dichtscbdhnach claim 8, characterized in that the upper shoe wall section (12) with a substantially uniform wall thickness opens into the sealing strip section and from the sealing strip section (11) extends radially outwards at an angle to the plane in which the sealing strip section is located, the radially outermost end of the shoe wall portion (12) integral with the upper end of the flexible wall section (13) is connected. 10. Sealing shoe according to claim 9, characterized in that the upper Bie wall section (13) with its lower end in one piece with the stabilizing wall portion (14) is connected, has a wall thickness which is thinner than the wall of the upper shoe wall portion and of the stabilizing wall section, that the stabilizing wall section (14) is uniformly thick, the wall thickness is greater than the wall thickness of the upper shoe wall section, and that the stabilizing wall section (14) has a length which is greater than the length of the upper shoe wall section (12), and an inner diameter which is larger than the outer diameter of the piston (20). 11. Sealing shoe according to claim 10, characterized in that the stabilizing wall section (14) runs parallel to the cylindrical walls of the metallic shell (18). -5- 909832/0752 12. Sealing shoe according to claim 11, characterized in that the upper shoe wall portion (12) based on the at an acute angle Wall of the stabilizing wall section (14) and that the upper Bie wall section (13) a curved connecting wall between the adjacent ends of the shoe wall section (12) and the stabilizing Wall section (14) forms. 13. Sealing shoe according to Claiml2, characterized in that the lower bending and Ro 11 wall section (16) has an inner diameter, which is larger than the inner diameter of the stabilizing wall section (14), the bending and rolling wall section (16) has a substantially uniform wall thickness of such a thickness that is smaller than the wall thickness of the stabilizing wall section (14). Patent attorneys Dipl.-Ing. Horst Rose Dipl.-Ing. Peter Kose! 909832/0752