GB1589038A - Clamping rings - Google Patents

Description

(54) IMPROVEMENTS IN CLAMPING RINGS (71) We, ROBERT BOSCH GMBH, a German company of Postfach 50, 7 Stuttgart 1, Federal Republic of Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to a clamping ring which is for use in co-axially clamping together two flanged parts, the clamping ring being a split ring defining a gap between its two ends which are disposed in a peripheral direction adjacent to one another and this gap being bridged by a screw connection to form a bracing point and to produce a tension in the clamping ring.

U.S.A. Patent Specification No. 2,724,410 describes a clamping ring for this purpose having flanges which overlap the flanges of the parts to be clamped together.

A disadvantage of such clamping rings is that, seen over the entire periphery, they are not uniformly applied as the screw connection is tightened so that their clamping force is uneven at various points of the periphery. The result in the application to the clamping together of two flanged parts of a cylinder housing of a diaphragm type brake housing is untight points on the cylinder. Such untight points mainly occur in the region opposite the tensioning point.

The present invention provides a split clamping ring for co-axially clamping together two flanged housing parts in which a gap is formed between the ends of the ring at a tensioning point and is bridged by a screw connection serving to tension the ring about the housing flanges, and in which the clamping ring has radially inwardly mutually diverging flanges between which the housing flanges to be axially clamped together can be received and circumferentially distributed radial notches are formed in the clamping ring flanges, all of which notches are spaced from a point of the clamping ring diametrically opposite the tensioning point.

The notches in the side flanges of the clamping ring increase its flexibility and help to ensure a uniform fit of the clamping ring over the entire periphery.

The clamping forces at the various points of the periphery are split up into identical moments by making the depth of the notches with a large lever low and with a small lever great.

Theoretically, it is therefore possible to provide a notch at the point directly opposite the tensioning point; however, this point is the one most prone to buckling anyway and must therefore remain unweakened.

The invention is further described, by way of example, with reference to the accompanying drawings in which: Fig. 1 is a sectional view of a diaphragm type brake cylinder having a clamping ring according to the invention, and Fig. 2 is a view of the clamping ring itself.

Referring to Fig. 1, a brake cylinder 1 is fitted with a diaphragm 2 which serves as a movable wall. An outer annular region 3 of the diaphragm 2 is made thicker towards the outside and is inserted between two flanges 4 and 5 of two cup-shaped cylinder housing parts 6 and 7 of the brake cylinder.

A clamping ring 8 is placed over the flanges 4 and 5. It is used for co-axially clamping together the housing parts 6 and 7 so that the diaphragm 2 is clamped at its outer annular peripheral region 3 firmly and sealingly between the two flanges 4 and 5.

Between the diaphragm 2 and one housing part 7 is a pressure medium working chamber 9 which may be supplied with pressure medium through a pipe connection 10 and between the diaphragm 2 and the other housing part 6 is an outside-air chamber 11 in which a piston rod 12 and a restoring spring 13 are disposed.

The clamping ring 8, as shown in Fig. 2, is a split ring having two ends 14 and 15 which lie closely adjacent one another in a peripheral direction but leave free between them a gap which is bridged by a screw connection 16. The screw connection 16 forms a tension point 17 for a tensional effect upon the clamping ring ends 14 and 15.

As Fig. 1 shows, the clamping ring 8 comprises a band bent to channel shape to define side flanges 18 and 19 for laterally overlapping the flanges 4 and 5. The side flanges 18 and 19 are inclined away from one another in a radially inward direction so that tightening of the screw connection 16 clamps the flanges 4 and 5 more tightly against the peripheral region 3 of the diaphragm 2. The two flanges 18 and 19 are identically provided with radial notches 20, 21, 22, 23 and 24 which are distributed, originating at a distance from a point 25 of the clamping ring 8 opposite the tension point 17, on the periphery thereof.

The notches 20, 21, 22, 23 and 24 are V-shaped and their base is rounded. They extend into the flanges 18 and 19 so that they take up only a part of their width.

As Fig. 2 shows, the notches 20 near the point 25 which is in a region opposite the tension point 17 are relatively shallow and the depths of the notches 21, 22, 23 and 24 progressively increases towards the tension point 17. Thus, of the width of the side flanges 18 and 19, there remains approximately 3mm at the notches 20 and only approximately lmm at the notches 24. As a result, the tensional forces at the various points of the periphery are split up into identical moments since the depth of a notch 20 to 24 is low with a large lever A and great with a small lever a. Moreover, it has proved advantageous to increase the spacing of the recesses 20, 21, 22, 23 and 24 towards the tensioning point 17.

Thus, when the screw connection 16 is tightened, uniform tightening of the clamping ring over the entire periphery is ensured and the thicker annular region 3 of the diaphragm 2 is clamped tightly and firmly between the two flanges 4 and 5.

Looking at the clamping ring 8 another way, the notches 20, 21, 22, 23, 24 increase the flexibility of the ring, the most flexible portions of the ring being those where the notches are deepest. Thus the bending moment due to the clamping force (i.e.

clamping force times the distance from the tensioning point 17) is greatest over those portions of the clamping ring which have the shallowest notches and which are therefore the stiffest. If all of the notches were of the same depth, the clamping ring 8 would tend to bend more sharply in the region of the point 25 remote from the tensioning point 17. This non-uniform bending would produce non-uniform clamping forces around the peripheral portion 3 of the diaphragm 2.

WHAT WE CLAIM IS: 1. A split clamping ring for co-axially clamping together two flanged housing parts in which a gap is formed between the ends of the ring at a tensioning point and is bridged by a screw connection serving to tension the ring about the housing flanges, and in which the clamping ring has radially inwardly mutually diverging flanges between which the housing flanges to be axially clamped together can be received and circumferentially distributed radial notches are formed in the clamping ring flanges, all of which notches are spaced from a point of the clamping diametrically opposite the tensioning point.

2. A clamping ring as claimed in claim 1, in which the notches are V-shaped.

3. A clamping ring as claimed in claim 2, in which the notches are rounded at their base and only take up part of the width of the flanges of the ring.

4. A clamping ring as claimed in any of claims 1 to 3, in which the notches in the region opposite the tensioning point are relatively shallow and their depth increases towards the tensioning point 5. A clamping ring as claimed in any of claims 1 to 4, in which the circumferential spacing of the notches increases towards the tensioning point.

6. A split clamping ring constructed substantially as herein described with reference to and as illustrated in the accompanying drawings.

7. A diaphragm brake cylinder whose cylinder housing comprises two cup-shaped flanged parts clamped together by a clamping ring as clamped in any preceding claim with the peripheral portion of a diaphragm sandwiched between the housing flanges.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. effect upon the clamping ring ends 14 and 15. As Fig. 1 shows, the clamping ring 8 comprises a band bent to channel shape to define side flanges 18 and 19 for laterally overlapping the flanges 4 and 5. The side flanges 18 and 19 are inclined away from one another in a radially inward direction so that tightening of the screw connection 16 clamps the flanges 4 and 5 more tightly against the peripheral region 3 of the diaphragm 2. The two flanges 18 and 19 are identically provided with radial notches 20, 21, 22, 23 and 24 which are distributed, originating at a distance from a point 25 of the clamping ring 8 opposite the tension point 17, on the periphery thereof. The notches 20, 21, 22, 23 and 24 are V-shaped and their base is rounded. They extend into the flanges 18 and 19 so that they take up only a part of their width. As Fig. 2 shows, the notches 20 near the point 25 which is in a region opposite the tension point 17 are relatively shallow and the depths of the notches 21, 22, 23 and 24 progressively increases towards the tension point 17. Thus, of the width of the side flanges 18 and 19, there remains approximately 3mm at the notches 20 and only approximately lmm at the notches 24. As a result, the tensional forces at the various points of the periphery are split up into identical moments since the depth of a notch 20 to 24 is low with a large lever A and great with a small lever a. Moreover, it has proved advantageous to increase the spacing of the recesses 20, 21, 22, 23 and 24 towards the tensioning point 17. Thus, when the screw connection 16 is tightened, uniform tightening of the clamping ring over the entire periphery is ensured and the thicker annular region 3 of the diaphragm 2 is clamped tightly and firmly between the two flanges 4 and 5. Looking at the clamping ring 8 another way, the notches 20, 21, 22, 23, 24 increase the flexibility of the ring, the most flexible portions of the ring being those where the notches are deepest. Thus the bending moment due to the clamping force (i.e. clamping force times the distance from the tensioning point 17) is greatest over those portions of the clamping ring which have the shallowest notches and which are therefore the stiffest. If all of the notches were of the same depth, the clamping ring 8 would tend to bend more sharply in the region of the point 25 remote from the tensioning point 17. This non-uniform bending would produce non-uniform clamping forces around the peripheral portion 3 of the diaphragm 2. WHAT WE CLAIM IS:

1. A split clamping ring for co-axially clamping together two flanged housing parts in which a gap is formed between the ends of the ring at a tensioning point and is bridged by a screw connection serving to tension the ring about the housing flanges, and in which the clamping ring has radially inwardly mutually diverging flanges between which the housing flanges to be axially clamped together can be received and circumferentially distributed radial notches are formed in the clamping ring flanges, all of which notches are spaced from a point of the clamping diametrically opposite the tensioning point.

2. A clamping ring as claimed in claim 1, in which the notches are V-shaped.

3. A clamping ring as claimed in claim 2, in which the notches are rounded at their base and only take up part of the width of the flanges of the ring.

4. A clamping ring as claimed in any of claims 1 to 3, in which the notches in the region opposite the tensioning point are relatively shallow and their depth increases towards the tensioning point

5. A clamping ring as claimed in any of claims 1 to 4, in which the circumferential spacing of the notches increases towards the tensioning point.

6. A split clamping ring constructed substantially as herein described with reference to and as illustrated in the accompanying drawings.

7. A diaphragm brake cylinder whose cylinder housing comprises two cup-shaped flanged parts clamped together by a clamping ring as clamped in any preceding claim with the peripheral portion of a diaphragm sandwiched between the housing flanges.