FR3052384A1 - INJECTION MOLD FOR THE MANUFACTURE OF A SEAL RING - Google Patents

Abstract

The present invention relates to a multi-part injection mold (100) for the manufacture of a sealing ring (1) in a mold cavity (2), with a first and a second outer portion (4; ) to form a sealing base body (8) and with a sleeve-shaped ejector (10) adapted to eject the sealing ring (1), the ejector (10) having a front surface (42) for forming a lateral surface (44) of the sealing base body (8), and with an inner portion disposed inside the ejector (10) for forming an inner contour of the sealing ring sealing (1) in the form of two sealing lips (14; 16) preferably arranged at an angle relative to each other, the inner part being made at least in two parts.

Description

Injection mold for the manufacture of a sealing ring

The present invention relates to a multi-part injection mold for the manufacture of a sealing ring in a mold cavity.

It is known to manufacture, in the state of the art, sealing rings using an injection mold, the injection mold being generally made from at least two injection-molded parts, a injection molded portion of the injection and / or nozzle side and an injection molded portion on the ejector side. The two injection-molded parts have hollow space sections that complement each other when assembling the injection mold with a single mold cavity in the form of the mold seal. During injection molding, a material, for example a plastic material, is liquefied and is injected under pressure into the hollow cavity of the mold. The injection molded sealing ring then cools and can be removed in a solid state after opening of the injection mold. In this case, the sealing ring generally remains on the ejector side from which it is then ejected using an ejector.

In order to form an injection mold for molding a sealing ring, milling or erosion is generally used by means of which hollow space sections are integrated into the injection molded parts to form the elements. desired sealing, for example sealing lips.

It is disadvantageous, however, in such injection molds manufactured, that complex structures and watermarks provided in the hollow space sections can not be formed by milling or erosion in the injection molded parts, such sections being for example desired to form sealing lips to the specific molding.

Alternatively, it is known to manufacture individual sealing elements of complex construction and vulcanize them immediately after a sealing ring.

It is disadvantageous in this case that such manufacture of the sealing ring requires very high work and cost. The object of the present invention is therefore to provide a multi-part injection mold for forming a sealing ring with complex sealing elements. The invention relates to a multi-part injection mold for the manufacture of a sealing ring in a mold cavity. In this case, the multi-part injection mold has a first and a second outer portion to form a seal base body and a sheath-shaped ejector adapted to eject the seal ring. The ejector has a front surface for forming a side surface of the seal base body. The multi-part injection mold has an inner portion disposed within the ejector to form an inner contour of the seal ring in the form of two sealing lips positioned relative to the other, preferably angled.

According to the invention, the inner part is made at least in two parts.

To form a sealing ring comprising complex and water-based sealing elements, in particular in the form of two sealing lips preferably placed at an angle relative to one another, it is proposed to form at least two parts the inner part of the injection mold into several parts. This makes it possible to simply form a cavity mold cavity section allowing the formation of fine structures, for example acute angles, in the sealing lips, these structures not being able to be manufactured from the process known in the state of the invention. technical, for example milling or erosion. In this case, the manufacture of the inner portion cut in half to form the presented mold cavity section is essentially simpler and cheaper compared to the formation of a mold cavity section. equivalent made in an inner part manufactured in one piece.

According to an advantageous exemplary embodiment, the first inner partial element is made in the form of a disc. In this case, it is provided that the first inner partial member contacts the first outer portion at least where the hollow mold cavity forms a sealing edge of the first sealing lip. The first inner sub-element forms the second inner sub-element at least at the point where the hollow mold space forms a sealing edge of the second sealing lip. The separate formation and the presented arrangement of the first inner sub-element makes it possible to form the sealing lips with a particularly acute angle, so that the sealing lips can be made with sharp sealing edges allowing a particularly good support. sealing lip against a component, for example against a shaft. The formation of such sealing edges is not possible with the methods known in the state of the art. An additional advantage of the first separately formed inner disk-shaped sub-element is that only the first inner sub-element has to be ground, for example to form a desired angle in the sealing lip. In this case, it is also advantageous that the first inner partial element can be rectified in a particularly simple manner, for example by rotation. It is possible to form the first inner partial element into several parts.

In another preferred embodiment, the first outer portion and the first inner partial member form a first mold cavity section forming the first sealing lip. According to another preferred embodiment, the two inner partial elements further form a second mold cavity section forming the second sealing lip. In this case, it is preferred when, as shown in another embodiment, the first and second mold cavity sections have a V-shape or a Y-shape in cross-section. inside the sealing ring allowing a particularly good support of the sealing lips against a component, for example a tree.

In another preferred embodiment, the second inner sub-element is cylindrical in shape with a flat outer casing surface resting on an inner casing surface of the ejector. In addition, according to an exemplary embodiment, it is preferred when the second outer portion comprises at least one inner casing-shaped inner surface made flat. In this case, it is intended to base an outer casing surface of the ejector on the inner casing surface of the second outer portion. This makes it possible to manufacture and mount in a particularly simple manner the outer casing surface of the second inner partial member, the inner casing surface of the second outer portion and the casing-like ejector casing surfaces, by example by rotation.

According to another preferred embodiment, the outer casing surface of the second inner partial member has a first larger outer casing surface area in the radial plane and a smaller second outer casing surface area in the radial plane. In this case, the ejector rests on the larger outer casing surface surface in the radial plane of the second inner sub-element. In addition, it is preferred, according to another embodiment, that the inner envelope surface of the second outer portion has a first larger inner envelope surface area in the radial plane and a second inner envelope partial surface area larger small in the radial plane, the ejector resting on the inner casing partial surface smaller in the radial plane of the second outer part. Preferably, a transition between the first and the second outer shell partial surface of the second inner partial member and a transition between the first and second inner shell partial surfaces of the second outer portion is realized as a step and the front surface of the sheath-shaped ejector terminates flush with the step. The separation peaks formed during injection molding on the lateral surface to be formed of the sealing base body and created at the level of the separation plane of the ejector and the second inner sub-element and / or the ejector and the second outer part can thus be moved, so that the sealed base body abuts, in case of mounting, directly against a component, for example a sealing ring support.

In order to form a lateral surface of the sealing base body more evenly abutting against the component, it is provided according to another preferred embodiment that the front surface of the ejector has an annular groove with a bottom surface. plane designed to form the lateral surface of the base sealing body. This makes it possible to form, on the front surface of the ejector, a hollow mold cavity section for forming a protrusion, particularly in the form of a step, on the lateral surface of the sealing base body. This makes it possible to form, at the edges of the projection formed, accommodating spaces in which the separating ridges can be accommodated during the mounting of the sealing ring.

In this case, the annular groove forms, according to another preferred embodiment, two surfaces extending from the bottom surface towards the front surface of the ejector, at least one of the surfaces being placed at an angle outwards. This makes it possible to produce, in the lateral surface to be formed of the sealing base body, a housing space that can easily be removed from the injection mold.

In the known ejectors, on the other hand, the ejector has a flat front surface forming a planar lateral surface of the sealing base body. The separation peaks forming at the contact surfaces between the ejector and the outer and / or inner part are not housed in the housing spaces. This causes problems when mounting the sealing ring in a component housing the seal ring, for example a seal ring holder, since the side surface of the seal base body does not abut because of the separating ridges, directly against the seal ring holder but may form a slot between the side surface of the seal base body and the seal ring holder. Since this problem occurs for all ejectors regardless of the configuration of the inner portion, another aspect of the present invention is to design a multi-part injection mold for the manufacture of a seal ring in a mold cavity, with a first and a second outer portion to form a seal base body and with a sleeve-shaped ejector adapted to eject the seal ring, the ejector having a front surface for forming a lateral surface of the sealing base body and with an inner part disposed inside the ejector for forming an inner contour of the sealing ring in the form of two sealing lips placed in angle relative to each other.

To solve the problem of separation peaks, it is anticipated that the front surface of the ejector has an annular groove with a flat bottom surface designed to form the side surface of the seal base body. This makes it possible to form a lateral surface in the sealed base body with a protrusion, particularly in the form of a step, so that housing spaces are formed at the edge of the projection and that separating ridges can be accommodated during assembly in said spaces.

Of course, this configuration of the multipart injection mold can also be combined with each of the other features mentioned above in combination or individually. Other advantages and advantageous embodiments are provided in the description, the drawings and the claims. In this case, the combinations of features provided in particular in the description and the drawings are only mentioned by way of example, so that the characteristics can also be combined differently or taken individually.

The present invention will be described in more detail later with the aid of exemplary embodiments shown in the drawings. In this case, the exemplary embodiments and combinations illustrated in the exemplary embodiments are only provided by way of example and do not affect the scope of the present invention. This is only defined by the appended claims, wherein: Figure 1 illustrates a schematic 3D lengthwise sectional view through a multi-part injection mold according to the present invention; and Fig. 2 illustrates a sectional view in the direction of the detailed schematic length through the multi-part injection mold.

Identical elements or the same function will be characterized later with the same reference.

Figure 1 illustrates a schematic sectional view in 3D diagrammatic length through a multi-part injection mold 100 for the manufacture of a sealing ring 1. In this case, the mold of injection 100 comprises during assembly a mold cavity 2 made in the form of the sealing ring 1. Figure 2 shows, for a better overview, a sectional view in the direction of the schematic length of the multi-part injection mold 100 with the sealing ring 1.

As shown in Figures 1 and 2, the injection mold 100 comprises a first outer portion 4 and a second outer portion 6 to form a sealing base body 8 of the sealing ring 1. In addition, the injection mold 100 comprises a sheath-shaped ejector 10 designed to eject the manufactured sealing ring 1. The injection mold 100 further comprises an inner portion disposed inside the ejector 10 to form an inner contour in the form of two sealing lips 14, 16 of the sealing ring 1 placed at an angle one with respect to the other.

In this case, the inner part comprises, as illustrated in Figures 1 and 2, a first inner part 18 disc-shaped and a second inner part 20 in the form of a cylinder. The two-part formation of the inner part of the injection mold 100 makes it possible to produce, in a particularly simple manner, the two sealing lips 14, 16 to be formed at an angle relative to one another.

As illustrated in particular in FIG. 2, the inner sub-element 18 contacts the outer part 4 at the place where the hollow cavity 2 forms a sealing edge 22 of the first sealing lip 14 and the second element Inner portion 20 at the location where the hollow mold space 2 forms a sealing edge 24 of the second sealing lip 16. The separate formation of the first inner sub-member 18 and its arrangement presented between the first outer portion 4 and the second inner partial element 20 makes it possible to produce the two sealing lips 14, 16 with a particularly acute angle α, α 2 which can not be achieved by means of the method known in the state of the art.

As further shown in FIG. 2, the outer portion 4 and the first inner partial member 18 form a first mold cavity section 26 forming the sealing lip 14. The two inner partial members 18, 20 in addition to a second hollow mold cavity section 28 forming the second sealing lip 16. In this case, the first outer part 4 and the second inner partial part 20 respectively form in the illustrated embodiment a spout 30, 32, so that the two mold cavity sections 26, 28 have a Y shape in the lengthwise sectional view of FIG. 2.

As illustrated in FIG. 1, the second inner sub-member 20 has an outer casing surface 34 formed flat on an inner casing surface 36 of the ejector 10. It can further be seen that the outer portion 6 comprises an inner casing surface 38 in the form of a sleeve made flat and abutting on an outer casing surface 40 of the ejector 10.

Alternatively, the ejector 10 may, as illustrated in FIG. 2, have a front surface 42 serving to form a side surface 44 of the sealing base body 8. In this case, the surface outer casing 34 of the second inner partial member 20 includes, for the formation of the lateral surface 44, a first outer casing partial surface 35 with a small diameter di and a second outer casing partial surface 37 with a large diameter Di . The ejector 10 abuts in this case on the outer shell partial surface 37 with the large diameter Di. In addition, the inner casing surface 38 of the second outer portion 6 has a first inner casing partial surface 39 with a large diameter D1 and a second inner casing partial surface 41 with a small diameter of the ejector. 10 resting on the partial surface of inner casing 41 with the small diameter of the. In this case, a transition is made between the first and second outer casing partial surfaces 35, 37 of the inner sub-member 20 and a transition is made between the first and second inner casing sub-surfaces 39, 41 of the outer part 6, in the form of a step 46 made. The front surface 42 of the ejector 10 ends in this case flush with the step 46.

The front surface 42 of the ejector 10 further comprises, as shown in FIG. 2, an annular groove 48 with a flat bottom surface 50 designed to form the side surface 44 of the sealing base body 8 This makes it possible to produce on the front surface 42 of the ejector 10 a hollow mold cavity section for the formation of a protrusion, particularly a step-shaped protrusion, in the lateral surface 44 of the sealing base body 8 The groove 48 may, as also shown in FIG. 2, have two lateral surfaces 52, 54 extending at an angle from the bottom surface 50 outwards towards the front surface 42 of the ejector 10. This makes it possible in the lateral surface 44 to form a sealing housing 8 with a housing space for accommodating the separation peaks. Such a configuration of the ejector 10 can also be achieved in the case of a flat support of the ejector 10 on the second inner partial element 20 and the second outer part 6, as illustrated in FIG.

Overall, a sealing ring with complex and water-tight sealing elements can be made with the multi-part injection mold shown. The injection mold comprises in this case a first and a second outer part, an ejector and an inner part, the inner part being made in two parts. Alternatively or in addition, the ejector has on a front surface an annular groove with a flat bottom surface, so that a hollow mold cavity section can be made for the formation of a projection on a surface. lateral surface of the sealing base body to be formed.

Claims (10)

A multi-part injection mold (100) for producing a sealing ring (1) in a mold cavity (2), with first and second outer portions (4; 6) for forming a sealing base body (8) and with a sleeve-shaped ejector (10) adapted to eject the sealing ring (1), the ejector (10) having a front surface (42) for the formation of a lateral surface (44) of the sealing base body (8) and with an inner part disposed inside the ejector (10) for the formation of an inner contour of the sealing ring (1). ) in the form of two sealing lips (14; 16) preferably arranged at an angle relative to each other, characterized in that the inner part is made at least in two parts. A multi-part injection mold (100) according to claim 1, characterized in that the first inner partial member (18) is disk-shaped and the first outer portion (4) is contacted at least one where the hollow mold space (2) forms a sealing edge (22) of the first sealing lip (14) and the first inner partial member (18) contacts the second inner partial member (20) at least one where the hollow mold space (2) forms a sealing edge (24) of the second sealing lip (16). A multi-part injection mold (100) according to any one of the preceding claims, characterized in that the first outer portion (4) and the first inner partial member (18) form a first hollow space section of mold (26) forming the first sealing lip (14) and / or the two inner partial members (18; 20) form a second mold cavity section (28) forming the second sealing lip (16) . A multi-part injection mold (100) according to claim 3, characterized in that the first and second mold cavity sections (26; 28) have a V-shape or a shape of Y. A multi-part injection mold (100) according to any one of the preceding claims, characterized in that the second inner sub-element (20) is cylindrical in shape with a planar outer casing surface (34) resting on an inner casing surface (36) of the ejector (10) and / or that the second outer part (6) has at least one inner casing-like inner casing surface (38), a outer casing surface (40) of the ejector (10) resting on the inner casing surface (38) of the second outer portion (6). A multi-part injection mold (100) according to any one of the preceding claims, characterized in that the outer casing surface (34) of the second inner partial member (20) has a first casing partial surface outer circumference (37) greater in the radial plane and a second smaller outer circumferential surface area (35) in the radial plane, the ejector (10) resting on the larger outer casing surface (37) in the radial plane of the second inner sub-element (20). 7. Multi-part injection mold (100) according to the preceding claim, characterized in that the inner casing surface (38) of the second outer portion (6) comprises a first inner casing partial surface (39) larger in the radial plane and a second radial inner casing sub-surface (41) smaller in size, the ejector (10) resting on the inner casing partial surface (41) smaller in the radial plane of the second outer part (6). A multi-part injection mold (100) according to claim 6 and 7, characterized in that a transition between the first and second outer shell partial surfaces (35; 37) of the second inner partial member (20; ) and a transition between the first and second inner envelope partial surfaces (39, 41) of the second outer portion (6) are embodied as a step (46) and the front surface (42) of the sheath-shaped ejector (10) terminates flush with the step (46). Multi-part injection mold (100) according to one of the preceding claims, characterized in that the front surface (42) of the ejector (10) has an annular groove (48) with a surface flat bottom base (50) for forming the side surface (44) of the sealing base body (8). Multi-part injection mold (100) for producing a sealing ring (1) in a hollow mold space (2), with first and second outer portions (4; 6) for forming a sealing base body (8) and with a sleeve-shaped ejector (10) adapted to eject the sealing ring (1), the ejector (10) having a front surface (42) for the formation of a lateral surface (44) of the sealing base body (8) and with an inner part disposed inside the ejector (10) for the formation of an inner contour of the sealing ring (1). ) in the form of two sealing lips (14; 16) arranged at an angle relative to one another, characterized in that the front surface (42) of the ejector (10) has a groove annular form (48) with a planar bottom surface (50) adapted to form the side surface (44) of the seal base body (8).