NL2012853A

NL2012853A - Container for segmented vulcanizing moulds with a spring mechanism.

Info

Publication number: NL2012853A
Application number: NL2012853A
Authority: NL
Inventors: Jan Bambuch
Original assignee: Pneuform Hulin
Priority date: 2013-06-05
Filing date: 2014-05-21
Publication date: 2014-12-08
Also published as: FR3006624A3; HU4524U; FR3006624B3; CZ26014U1; FI10371U1; SK501302013U1; NL2012853C2; PL122600U1; KR20140006270U; ITBO20130138U1; DE202013104830U1; SK6981Y1; RU147797U1

Description

Container for segmented vulcanizing moulds with a spring mechanism

Technology field

The invention concerns the container for segmented vulcanization moulds with a spring mechanism for the manufacture of tyres, where the spring mechanism prevents the container upper plate from damage and deformation.

Current state of the art

Tyres are vulcanized in press machines equipped with vulcanization containers of segment construction (Fig.l). The segment vulcanization mould 50 is inserted into the vulcanization container, this mould consists of the upper semi-mould and the bottom semi-mould, which are attached in respective parts of the container. The container is attached in between the press upper ram not shown in the figures, and the bottom press ram. The upper semi-mould of the vulcanization mould is attached to the press upper ram, and the bottom semi-mould of the vulcanization mould is attached to the press bottom ram. The press upper ram is divided into two bases - the upper outer plate 60 (ring) and the upper inner plate 70 (ring), these two parts movie independently of each other. The spacing ring 11 is firmly attached to the outer plate 60, under the ring is attached the conical ring 12 in mechanical contact. A T-shaped guideway 13 with a detent is connected to the conical ring (12). The guideway 13 is slidingly connected to segments 51 of the vulcanization mould (50). To the upper plate 70 of the press ram is attached the container upper plate 41 to which are attached parts of the upper semi-mould of the vulcanization mould, i.e. the upper lateral ring 52, to which is attached the upper base ring 53. Carriers 21 are slidingly mounted on the upper plate 50. The bottom semi-mould of the vulcanization mould 50 is composed of the bottom lateral ring 54 with a bottom base ring 55, which are attached to the bottom plate 31 of the container 100.

Carriers 21 of the vulcanization container and in them fixed segments 51 of the vulcanization mould are mutually slidingly mounted by means of a T-shaped groove 24 and a T-shaped guide way 13 with a detent, thereby they are slidingly connected with the conical ring 12. This mounting allows for the transformation of vertical movement of the conical ring 12 into radial movement of the carriers 21 and in them fixed segments 51 of the vulcanization mould when the vulcanization container is being closed (opened). At the same time, the carriers 21 are slidingly mounted in the container upper plate 41 by means of the upper T-shaped guideway 23. This mounting allows for radial horizontal movement of carriers 21 towards the centre of the vulcanization container. The ability of mutual movement of the inner and outer plate of the press ram provides for opening of the vulcanization mould, closing of the mould and creating a constant afterpressure prevailing in the mould after it has been closed, i.e. pre-tension P. The pre-tensioning P is created by offsetting the spacing ring 11 in respect to the upper plate 41 of the container by 0.4 mm to 1 mm, as shown in Fig. 2. As the container carriers 21 and in them attached segments 51 of the mould are closed by sliding movement of the taper formed in the vulcanization container, the vulcanization container taper must be offset in respect to the upper semimould. This offset of the conical ring in respect to the upper plate should be measured on assembling the vulcanization container under a pressure load substituting the closing force of the press in such manner that upon closing the press, with the ram outer plate and the ram inner plate being in an end position, the closing (pressure) forces could be constantly transferred through the vulcanization container taper. These pressure forces cause continual closing of the vulcanization container, which is needed for a high-quality tyre vulcanization process. The forming forces of pressure media act against the pressure forces in the bladder of the vulcanization mould 50. Should these pressure forces be surpassed by the forming forces of the bladder, the vulcanization container and mould would partially open, which would entail the penetration of compound (tyre stock) in between the mould segments 51, the upper lateral ring 52 and bottom lateral ring 54, which can lead to the creation of visible flashes (fins) in a tyre. The set pretension in the vulcanization container makes sure that the vulcanization container is constantly closed.

The current construction of vulcanization containers with a different suspension of the container conical ring 12 and the container upper plate 41 (Fig. 2) cause deformation of the container upper plate 41 due to the action of forming pressure forces of the bladder in the vertical direction. This contributes to the jamming of functional surfaces of the upper T-shaped guideway 23 and carriers 21 of segments 51 sliding on the deformed upper plate 41. This bring about a gradual deformation of respective parts of the segmented vulcanization container, which are in turn transferred to the vulcanization mould segments 52, this also causes defects on moulded tyres. For the above-mentioned reasons, the segment vulcanization containers must undergo repairs after some time. In order to repair the segmented container and moulds, they must be put out of operation for several weeks.

The basis of the technical design

Disadvantages of known containers are removed to a considerable extent by the container for segmented vulcanization moulds equipped with a spring mechanism pursuant to the invention. The container contains a spacing ring to which a conical ring is assigned, a guideway is assigned to the conical ring, the guideway is slidingly connected to the carriers and vulcanization mould segments. The spacing ring is assigned to the upper outer plate of the press upper ram. The substance of the technical design consists in that the spacing ring and conical ring are movably connected by a spring mechanism.

In accordance to the advantageous technical design the spring mechanism consists of a pin firmly mounted in the conical ring under the first recess formed in this conical ring. This pin runs through the opening made in the spacing ring to the second recess made in this spacing ring. In the first recess on the pin there are mounted springs which rest by one side against the vertical side of the first recess and by the other side they rest against the first washer, with the first washer resting against the bottom side of the spacing ring. In the second recess on the pin there is fixed the second washer which is in contact with the horizontal side of this second recess, two fixing nuts are mounted on the pin above the second washer, on the conical ring is formed a notch into which fits the seating formed on the spacing ring.

The advantage of the invention is that the springs mounted between the spacing ring and conical ring provide for a set pre-tension which ensures constant closing of the vulcanization mould and serves to overcome the pressure load caused by the bladder pressure. Positioning of the springs removes and eliminates any mechanical contact between parts of the segmented vulcanization container and, simultaneously thanks to the spring lift, enables eliminating clearances in all parts of the container and mould when they are to be closed. By compressing the spring mechanism the automatic inaccuracies and clearances of respective parts of the vulcanization container are compensated. This arrangement significantly lowers any possible mechanical damage to respective parts of the vulcanization container. The use of spring mechanisms lowers demands and cost of maintenance, prolongs the life cycle of the vulcanization container, eliminates any deformation of the container upper plate and jamming of functional surfaces of segment carriers.

Overview of the figures in the drawings

The invention is explained in detail by means of figures which show:

Fig. 1 - represents the vulcanization container of segmented construction of the prior art

Fig. 2 - represents the setting of the structural pre-tension by offsetting the conical ring in respect to the container upper plate of the prior art Fig.3 - represents the arrangement of the vulcanization container with the spring mechanism pursuant to the technical design

Fig. 4 - represents the setting of spring mechanism pretension when the container is not closed Fig. 5 - represents the setting of spring mechanism pretension when the container is closed Fig. 6 - represents the top view of the container with the arrangement of spring mechanisms along the container circumference

Fig. 7 - represents the action of forces inside the vulcanization container when tyres are manufactured

Description of the exemplary embodiment

The container 100 of segmented construction (hereinafter Container) for tyre moulding according to Fig. 3 is mounted between the press upper ram and press bottom ram not shown in the figures. The press upper ram is divided into two bases - the upper outer plate _6_0 (circular) and the upper inner plate 7_0 (circular) , with these two plates moving on each other independently. The segmented vulcanization mould 5_0 (hereinafter mould) with tyre tread pattern is fixed into the container 100. This mould 5_0 consist of the upper semi-mould and bottom semi-mould, with the upper semi-mould connected with the press upper ram, the bottom semi-mould is in turn connected with the press bottom ram.

The spacing ring 1_1 is firmly fixed to the upper plate _6_0, which is movably connected through a spring mechanism _1_0 with the conical ring 1_2. The T-shaped guideway 1_3 with a detent is connected to the conical ring 1_2. The guideway 1_3 is slidingly connected with the carriers 2_1 of the container 100, which are firmly connected with segments 5_1 of the mould 50.

The container upper plate 4_1 is attached to the upper inner plate 7_0 of the press ram, to this plate 4JL are attached parts of the upper semi-mould of the vulcanization mould 50, namely the upper lateral ring _52, to which is connected the upper base ring _53. The upper inner plate 7_0 is also connected to container carriers 5_1. The bottom semi-mould of the vulcanization mould 50 is composed of the bottom lateral ring _54 and the bottom base ring _55, these rings are in turn attached to the bottom plate 3_1 of the container 100. The bottom plate 3_1 is attached to the press bottom ram not shown in the figures.

Container carriers 2_1 and in them attached segments 51 of the vulcanization mould 5_0 are at the same time slidingly mounted in the container upper plate 41_ by means of the upper T-shaped guideway 2_3. This mounting allows for a radial movement of container carriers 2_1 towards the centre of the container 100. When the container 100 closes (opens), the car- riers 2_1 move as well as in them fixed segments 5_1 of the mould 5_0 along the taper of the conical ring 1_2. This process is enabled by dividing the press upper ram into an independent upper plate _6_0 and inner plate 7_0, as was described above.

The ability of mutual movement of the upper plate 6_0 and inner plate 7_0 of the press upper ram allows for the vulcanization mould opening, vulcanization mould 5_0 closing and keeps a constant afterpressure on the mould 5_0 when it is closed, i.e. the pre-tension "P". As the vulcanization container 100 is closed at the moment when the segments 5_1 of the vulcanization mould 5_0 get in full contact with the upper lateral ring 52_ and the bottom lateral ring _54 of the vulcanization mould 5_0, a pre-tension must be created here, which is made by the spring mechanism 10.

Spring mechanism 1_0 (Fig. 3,4,5) consists of a pin 10.1, which is firmly mounted in the conical ring 1_2 under the first recess 10.2 formed in this conical ring 1_2. This pin 10.1 is led from the conical ring 1_2 through an opening 10.4 into the second recess 10.3, which is made in the spacing ring 11. In the spacing ring 11_ is formed the opening 10.4. Springs 10.5 are mounted in the first recess 10.2 on the pin 10.1, these springs rest by one side against the vertical side 10.21 of the first recess 10.2 and by the other side they rest against the first washer 10.6, which rests by the other side against the bottom side 11.2 of the spacing ring 1_1. The second washer 10.7 is attached in the second recess 10.3 on the pin 10.1, this washer is in contact with the horizontal side 10.31 of this second recess 10.3. Over the second washer 10.7 there are mounted two fixing nuts 10.8 on the pin 10.1. A notch 12.1 is cut in the conical ring 1_2 and into this notch fits to the seating 11.1 formed in the spacing ring 1_1. Figure 6 represents the top view of the arrangement of spring mechanisms 1_0 along the circumference of the container 100. The number of spring mechanisms is given by the size of the vulcanization container 100.

The flexible joint by means of the spring mechanism 10 between the spacing ring 1_1 and conical ring 1_2 allows for their mutual sliding movement and simultaneously guarantees a firm attachment of the spacing ring 1_1 to the container coni cal ring 1_2. Springs 10.5 inserted between the spacing ring 11_ and conical ring 1_2 provide for setting up of pre-tension "P" in between functional parts of the container and the vulcanization mould. This arrangement guarantees a constant closing of the vulcanization mould and serves to overcome the pressure load caused by the pressure induced by the mould bladder. Springs 10.5 remove and eliminate any contact between parts of the segmented vulcanization container and, simultaneously thanks to the spring lift, enable to compensate any clearances between container parts and the mould on closing.

Fig. 4 represents the container before closing. The spring mechanism JL_0 is not compressed by the application of pressure through the outer plate _6_0 of the press upper ram, the container is in the closing phase. Considering the arrangement of springs 10.5, these springs are not compressed and a clearance between the spacing ring 11_ and the conical ring 1_2 is compensated for and marked by letter B. This clearance is designated as the container uplift.

Fig. 5 represents a container in the closed state. Compressed springs 10.5 create a pre-tension and afterpressure which is transferred through the conical ring taper 1_2 onto the carriers 2_1 and segments 5_1 of the mould 5_0. The value of applied compressive force of the spring mechanism JL_0 is given by the number of springs 10.5, by their shape and a preset value B. When the vulcanization container (Fig. 1) is being closed, the springs are compressed, the value B - container uplift is minimum. The magnitude of the compressive force induced by springs 10.5, i.e. pre-tension, may be accommodated by setting the uplift using the nuts 10.8, thereby decreasing and/or increasing the value B, i.e. the container uplift. When the container is being closed by the spring mechanism JL_0, the compressive force of the press gradually increases and acts on the segment carriers 2_1 of the vulcanization mould.

Arrangement of forces during tyre manufacture is represented in a diagram in Fig. 7, where:

Fuz - is the closing force of the vulcanizing press acting through the taper of the vulcanization container Fub - is the closing force of the vulcanizing press acting through the upper semi-mould

Fuc - is the force of the press bottom plate acting on the bottom semi-mould

Pmem - is the pressure of the pressure media in the mould bladder

Fmb - is the force of the vulcanizing press bladder acting onto the sides of the vulcanization container Fmo - is the force of the bladder acting in radial direction Fmk - is the component of force Fmo acting in vertical direction against closing of the vulcanizing press.

Claims

A container (100) for segmental vulcanization forms with a spring mechanism, the container including a spacer ring (11) to which a conical ring (12) is assigned; a guide element (13) is assigned to the conical ring (12) and is movably connected to the carriers (21) and the segments (51) of the vulcanization form, the spacer ring (11) being assigned to the outermost top plate of a ram block of the press, characterized in that the spacer ring (11) and the conical ring (12) are movably connected by a spring mechanism (10).

Container according to claim 1, characterized in that the spring mechanism (10) comprises a tap (10.1) which is fixed in the conical ring (12) under a first recess (10.2) made in this conical ring (12); this tap (10.1) is guided through an opening (10.4) made in the spacer ring (11) to a second recess made in this spacer ring (11); on the pin (10.1) in the first recess (10.2) are placed springs (10.5) which lean with one side against the vertical side (10.21) of the first recess (10.2), and with the second side against a first supporting plate ( 10.6), wherein the first side plate (10.6) leans with the other side against the lower side (11.2) of the spacer ring (11); on the stud (10.1) in the second recess (10.3) a second washer (10.7) is arranged, which is in contact with a horizontal side (10.31) of this second recess (10.3); above the second washer (10.7) on the stud (10.1) are two fixing nuts (10.8); and a notch (12.1) is made on the conical ring (12), into which the seat (11.Im made on the spacer ring, (11)) falls.