JPS5877730A - Annular metallic frame body for sealing and its manufacture and manufacturing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for manufacturing an annular metal reinforcing frame for sealing between a rotating shaft and its housing, as well as to these frames.

The present invention relates in particular, but not exclusively, to the reinforcing frame of a lipped seal formed by a ring whose axial half-section has an L-shape, i.e. a right angle.

In the prior art of these annular frames, these frames are generally formed by cutting flat discs from a metal sheet and stamping the discs.

This method produces wrinkles and other irregularities in the pressed material, and particularly produces very large scrap, the amount of wasted scrap being greater than the amount of metal forming the frame.

In order to eliminate these drawbacks, conventionally the metal strip is first cut into lengths and then each of these lengths is wound in a circle until its ends abut to form a cylindrical ring.
Finally, methods have already been proposed in which the ring is laterally deformed so as to form the desired frame shape.

This known method actually reduces waste of metal.

However-1 in order to deform the ring laterally according to this method, several successive die-cuts are required.
A step of tamping has to be carried out, the final step of which is to create a separate preform 1 by bending one of the axial edges of the ring slightly inside the ring, similar to an internal chamfer. It is done in advance. The edge is provided with a triangular cutout at the front to eliminate the risk of wrinkles.

This method is relatively time consuming and expensive, there is metal wastage due to the cutouts, and the frame formed therein has a certain degree of fragility due to the corresponding slits.

The aim of the invention is to improve frames manufactured on the one hand, whose circular edges are continuous outside the area corresponding to the previous abutment, but which The different parts of the frame are formed by smooth surfaces without wrinkles, and the formed parts may even be locally stronger than the original band. On the other hand, the object of the invention is to make the manufacture of the frame even faster and more economical,
Their lateral deformation is done in one pass.

For this purpose, the lateral deformation of each ring is basically carried out according to the invention by moving said ring in - times through a narrow annular space formed between two parallel guide surfaces s, s'. This is done by pushing it axially into the cavity, which has a shape complementary to the shape of the entrance beam of the cavity, and whose bottom has a shape complementary to the shape of the frame to be produced.

A device for carrying out this modification method is basically according to the invention and is characterized by the following: That is, it comprises an outer container body, a central core located inside it at the bottom of the container body, the core rod having an outer surface S′ which, together with an inner surface S of the container body, jointly receives the ring during its deformation. A bell-shaped punch having a thin-walled cylindrical skirt and a narrow annular cavity adapted to be guided is arranged such that the skirt slides cooperatively in the axial direction into the inlet of said volume. S, the cross-section of this skirt has the shape of a ring, the dimensions of which are equal to the dimensions of the edge of the ring to be pressed.

According to a preferred embodiment, the device is adapted to press the ring between the mandrel and the top of the bell-shaped punch such that the mandrel rests firmly against the bottom of the container body during the formation of the frame. further comprising an elastic compression device axially interposed therebetween, wherein after the formation of each frame, not only the punch but also the mandrel are pressed against the container body so that the frame can be removed from the container body. It can be taken out into a container.

Apart from these main devices, the invention comprises other devices which are preferably used simultaneously and which will be explained more clearly below.

Preferred embodiments thereof will now be described with reference to the accompanying drawings. Of course, the invention is not limited to this example.

In this embodiment, we provide a method for manufacturing an annular frame l attached to a lipped seal 2 to be mounted in a cylindrical bearing 3 and to provide a seal around a rotation axis 4 passing through this bearing. .

The annular seal 1 is press fit into the bearing 3 and extends radially with half of its axial cross section being L-shaped, ie at right angles.

In order to manufacture such a frame, metal strip member 5 (second
) is required, the nature and dimensions of which are chosen according to the end use of the frame.

The thickness of this strip member 5 is generally 0.3 to 1.5 m, preferably 0.6 to 0.8 m.

The width of the band member is generally 5 to 30 m, preferably 10 to 2011 m.

Regarding the material of this band member, steel is generally used, and stainless steel or brass is also used.

The strip 5 is cut into equal length sections along a line perpendicular to the length of the strip, preferably along the swallowtail fold line 6.

Each of these thus cut parts is rolled up until its ends abut to form a swirling cylindrical ring 7 (FIG. 3).

Although not absolutely necessary, this cylindrical shape is held in place by joining adjacent ends of the sections together, particularly by welding, gluing, or clipping, and then attaching these ends, as best shown in FIG. The cut is made along the fold line 6 by inserting a tenon 8 projecting from one end into a complementary mortise 9 cut out in the other end.

In order to transform this cylindrical ring 7'l into the desired annular frame 1 (FIGS. 1 and 4), this ring is pushed axially into a type of mold which is formed by rising on suitable guide surfaces. be done.

In fact, the applicant noticed the following: that is, so as to guide the ring along its two faces in such a way that it does not collapse or float during its deformation.
If these surfaces are designed, such desired deformations can be obtained very easily, even when cold, by such indentation carried out in one pass.

To form these guide surfaces, a device consisting of the following is used: That is, the inner space of the container body 10o is formed by a surface S whose lower part is formed by a flat horizontal bottom and whose side part is formed by a cylindrical turning surface about a vertical axis, and such a bottom surface and cylindrical surface are rounded. a cylindrical pivoting mandrel 11° which is preferably mounted on the bottom of the container body 10 via a disc 12 forming an integral part of the mandrel; The outer surface S' of the mandrel extends inside and parallel to the inner surface S of the container body when the mandrel is located on the bottom of the container body, and is deformed. Should be the thickness of ring 7! located away from said inner surface S by a slightly larger narrow distance.

A bell-shaped punch 13° covering the core rod 11; the actuating annular portion of this punch has surfaces S and S opposite to the upper cylindrical portion;
' forms a fitting cylindrical skirt part 13, the lower part of which ends in an annular surface of the same size as the edge of the ring 7 to be pushed.

In other words, this cylindrical skirt portion 131 has a radial thickness equal to .

The hem portion is very thin, the value e is generally less than l, and the length in the axial direction is generally more than 10 mm.

In order to avoid deformation of the hem part when pushing the ring 7 in the axial direction, it is e.g. 160-200 k
Although made of a mechanically very strong material such as steel with a tensile strength of g/m%, its joint guidance between the two surfaces S and 87 already eliminates a great risk of its deformation during the pushing operation. Pay attention to what you are doing.

An elastic device 1 is installed between the top 13□ of the bell punch and the 8 rod 11.
4 is interposed so that during the pushing of the ring 7, a sufficient force is applied to the bottom of the container body 19 on this bar 8, so that the pushing causes them to separate (despite the force, these 8 bars Mutual contact between the two parts is maintained.

These elastic devices 14 are formed, for example, by helical springs as shown schematically in FIGS. 5 and 6, or by any other desired method, such as by pneumatic or hydraulic elements. .

Furthermore, a device is advantageously provided for connecting the eight rods 11 and the punch 13 together while limiting their axial mutual spacing, which device is not shown;
Thus, after the frame 1 has been manufactured, the eight rods 11 can be easily removed from the container at the same time as the punch 13 in order to remove the frame from the container.

The method for forming such a frame is as follows.

That is, when the assembly of the 8 rod 11 and the punch 13 is taken out from the container body 10, the cavity is open at its top, the ring 7 is located therein, and its outer surface is the inner surface of the cavity. It is in common contact with S.

The 8 rod 11 and the punch 13 then fit into the container body thus provided, this fit being such that the 8 rod is in contact perpendicularly to the bottom of the container body and the punch is in contact with the upper edge of the ring 7. (see FIG. 5) can be facilitated by suitable guiding devices, such as chamfered surfaces.

Then, press the punch 13 in the direction of arrow F in FIG.
The skirt portion 13□ forming its working part is pushed into the annular space between the container body and the eight rods.

Such a pushing action compresses the spring 14, which causes the 8 bar 11 to firmly abut against the bottom of the container body 10, and in particular the ring 7 is pressed downwards, the metal forming the base of this ring then being compressed. flows only in amounts useful for that purpose. That is, the vertical annular space between the top circumference of the 8 bar and the bottom circumference of the container body, and this metal is thus forced into the axis of the assembly until that space is filled, as shown in FIG. direction into this space.

The forming operation then ends.

Then, the assembly of the 8 rods 11 and the punch 13 is assembled into the container body 1.
It is removed vertically from 0. For that, punch 1
3, this operation causes the punch 13 and the 8 bar 11 to move away from each other due to the relaxation of the spring 14, and the 8 bar itself is then removed from the container body.

The frame 1, which is shaped and located at the bottom of this container body, is then removed from the container body.

The surface of the frame thus obtained has, at the end of its forming operation, a shape that is strictly complementary to the portions of the guide surfaces S and S' that sandwiched the frame.

In particular, said part complies with these conditions and in particular the first
If a good seal is provided between the frame and a housing with a complementary smooth surface by simply pushing this frame into the housing, as in the illustrated embodiment, all said surfaces are completely smooth in terms of texture and without wrinkles or other irregular irregularities.

For such a push-fit, the frame 1 is therefore radially compressed and the two abutting ends of the length of the strip forming the frame are tightly stacked together. This firm overlapping action guarantees itself an excellent seal at discrete levels of the ring. “In general, however, the frame is completely embedded within the rubber or elastomer mass, so there is no need to seal the two abutting ends. This is because in most cases there is no need to stop.

Furthermore, the frame 1 is produced without wastage except for the several ends of the starting strip 5.

That is, in particular, there is no waste from the notches that are cut out to prevent wrinkles.In fact, the economical efficiency of this lack of waste is extremely large.

Also, frames made in this way are stronger than those made by conventional methods because there are no notches on their circular edges.

Furthermore, the above-mentioned axial pushing action makes the cylindrical portion of each frame corresponding to the leg 1 of the axial semi-relaxed section denser,
By making the wall slightly thicker, the mechanical strength of the frame increases.

A moxibustion frame formed according to the invention can be distinguished by the fact that the result of the two ends of the band forming it being abutted against each other is visible.

Whatever the embodiment, the end result is a method and apparatus for manufacturing annular frames for lipped seals and the like, the features, performance and advantages of which will be fully apparent from the foregoing.

As is already clear from the foregoing, the invention is not limited to the embodiments specifically described here, but encompasses all variants, in particular the following. That is, cases where the axial pressing of the ring is not performed cold but at a temperature higher than the ambient temperature, or when the manufactured frame is cut in half in the axial direction.

If the surface has a shape other than an L-shape, such as a 7-, 5-, or 2-shape, or the initial length of the strip is obtained by cutting a narrow strip in the transverse direction ( and by cutting the wide strip in the transverse direction.

In that case, the former cut corresponds to the smaller side of the obtained part, whereas the latter cut corresponds to the larger side of the obtained part.

[Brief explanation of the drawing]

FIG. 1 shows an axial half-I section of a lipped seal with a metal annular frame according to the invention, and FIG. 2 a plan view of a metal strip making up the frame according to the invention. 3 is an axial sectional view of a cylindrical ring representing the intermediate part of such a manufacturing stage, FIG. 4 is an axial sectional view of a frame made by this method, and 5. 6 is a schematic axial cross-sectional view of a forming machine constructed in accordance with the invention for forming a frame as shown in FIG. 4 from a ring as shown in FIG. 3, in two successive operating stages; FIG. . [Explanation of symbols]

Claims (1)

[Claims] 1. characterized by having a smooth surface and a connecting line by the juxtaposition of the two ends of the length of the rolled-up strip forming a frame with two continuous edges; An annular metal frame for sealing. 2 Thickness of the initial metal strip (5) 110.3 to 1.5
An annular metal frame for a seal according to claim 1, characterized in that it has an m-wing, preferably a diameter of 0.6 to 0.8. 3. by cutting a metal strip (5) into lengths and winding each of these lengths in a circle until its two ends abut to form a cylindrical ring (7), Half of the axial cross-section is then folded by inserting it in one pass axially into a thin-thickness cavity formed between two parallel guide surfaces (s, s'). A seal which is deformed laterally, wherein the entrance to the cavity has a shape that complements the shape of the ring, and the bottom part has a shape that complements the shape of the frame to be formed. A method for manufacturing an annular metal frame. 4. The outer container body (10) is arranged inside it on the bottom of the container body, and its outer surface (S') is connected to the inner surface (S') of the container body (
A central rod (S) forms a narrow annular cavity that collectively receives and guides the ring during its deformation.
11) and. An apparatus for manufacturing an annular metal frame for a seal, the cross section of which has a ring-island shape. 5 By pushing in the ring (7), the frame (1)
An elastic member axially interposed between the core rod (11) and the top of the bell-shaped punch (13) so as to firmly abut the core rod against the bottom of the container body (10) during the formation of the container body (10). compression means (14), after forming each frame, so that the frame can be removed from the container body.
5. The manufacturing apparatus according to claim 4, wherein not only the punch but also the core rod can be easily taken out from the container body.