DE102013002258A1 - Mold for manufacturing of flexible joint disks for transmitting torque between shaft ends, has supply channel arrangement that includes end portions extending perpendicular to wall of mold cavity and having openings aligned to wall - Google Patents

Abstract

The mold (10) comprises two closely cooperating mold sections (10A,10B) that define a mold cavity and embedded in an elastomeric matrix reinforcement insert (12). A positioning element is provided in the reinforcing insert. A supply channel arrangement (14,38,42,44,46,48) through which the moldable elastomeric material is supplied the mold cavity at different positions, is provided at a supply head. The end portions of the supply channel arrangement extend perpendicular to an outer peripheral wall (58) of the mold cavity and has openings (54) aligned to the wall in the mold cavity.

Description

The invention relates to a mold for the production of flexible discs comprising a reinforcing insert embedded in an elastomer composition with at least two closely cooperating mold parts which together define a mold space, with positioning means for positionally accurate insertion of the reinforcing insert and with a feed channel arrangement, via which moldable elastomeric material the mold space can be fed in different places.

Articulated discs made with such a shape serve to transmit torques between two shaft ends, such that torque peaks are cushioned and the two shaft ends are vibrationally and acoustically decoupled.

By the present invention, a form according to the preamble of claim 1 is to be developed so that the function and service life of the joint discs produced with it is improved.

This object is inventively achieved in that end portions of feed channels extend substantially perpendicular to a wall of the mold space and are aligned with openings of this wall substantially.

With the mold according to the invention it is possible to avoid voids in the elastomer composition. In addition, it is achieved that the injected elastomer material bonds well with the reinforcing insert, that is, consistently has good, load-bearing surface contact with the surfaces of the reinforcing insert.

Advantageous developments of the invention are specified in subclaims.

A development of the invention is characterized in that the feed channel arrangement is formed in a feed head and the feed head is thermally insulated from the mold space by an insulating layer.

With such a mold, it is possible to slightly heat the supplied uncrosslinked elastomeric material, so that its flow properties are improved. On the other hand, such a strong warming is avoided, that even on the way to the form space, the networking begins significantly. Due to the thermal insulating layer between the mold cavity and the feed channel arrangement, it is possible to set corresponding temperature differences with low energy input.

A development of the invention is characterized in that the insulating layer is a ceramic layer or a plastic layer.

This development is in terms of mechanical robustness and precision machinability of the insulating advantageous.

A development of the invention is characterized in that at least a part of the channels of the feed channel arrangement is provided with control means.

In such a mold, one can adjust the flows of elastomeric material which flow through the various feed channels. In this way it becomes possible to quickly fill the mold, on the other hand not to fill too quickly, which could lead to voids and poor adhesion of the elastomeric material to surfaces of the reinforcing insert.

A development of the invention is characterized in that at least part of the control means is designed as a throttle, which is preferably at least partially formed by a channel or channel portion of the feed channel arrangement.

This type of formation of the throttle means has the advantage that it can not be adjusted unintentionally and causes no significant additional costs.

A development of the invention is characterized in that at least part of the control means is formed by controllable constrictions.

In such a mold, one can adjust the flow rate in the various feed channels according to the requirements without having to perform mechanical work on the mold. In this way it is possible to inject in the same form different elastomeric materials, for example, to realize joint discs of different compliance in the circumferential direction. Also, one can easily compensate for changes in the composition of delivered elastomeric materials. Finally, one can also vary the delivery rate of elastomeric material from the various feed channels in the course of a filling process of the mold.

A development of the invention is characterized in that at least some of the controllable constrictions comprise a hose valve or a cooling section.

The control of Elastomermaterialflusses, which is obtained with this development, takes place without moving parts. This is interference with the Throttle means or the valve means largely eliminated A development of the invention is characterized in that the feed channel arrangement and / or provided in its control means are designed so that at least a portion of different windows of the mold space are acted upon at the same throughput with elastomeric material.

With such a mold, the same quantity of elastomer material is supplied per unit of time in different regions of the mold space.

A development of the invention is characterized in that the feed channel arrangement and / or approximately provided control means are designed and / or controlled so that the mold space is filled substantially from bottom to top with elastomeric material.

This development is advantageous in terms of keeping available in the mold cavity air (or other gases) free access to a vent.

A development of the invention is characterized in that a quantity meter is arranged in the feed duct arrangement and the control for the control means takes place as a function of the output signal of the flow meter.

How high the elastomeric material currently stands in the mold cavity, can be determined in a simple manner by determining with a flow meter the total amount of material already supplied to the mold space at a given time. This amount is unambiguously associated with the height of the elastomeric material level in the mold cavity. The corresponding characteristic can easily be determined experimentally.

A further development of the invention for the production of flexible discs, in which the reinforcing insert comprises loop packs, is characterized in that windows of the mold space communicate with a partial space of the mold space, which are occupied only to a small extent by the reinforcing insert.

If the reinforcing insert in the forming space comprises loops packages, that is to say reels of threads capable of being subjected to tension, which are held together by a preferably elastomeric material, a deformation of the loop packages can take place by flowing in the highly viscous elastomer material. With the development just described such deformation is avoided, since the injected elastomer material meets the loop packages of the reinforcing insert at most little.

A development of the invention, in which the mold space is substantially symmetrical to a center plane, is characterized in that the parting plane between the two mold parts substantially coincides with the plane of symmetry of the mold space.

This development is in view of a void-free filling of the mold space of advantage.

A development of the invention, in which the mold space is substantially symmetrical to a center plane, is characterized in that the parting plane between the two mold parts substantially coincides with the plane of symmetry of the mold space.

In this development it is achieved that the supply of elastomeric material is coordinated with the local geometry of the reinforcing insert.

A development of the invention is characterized in that it has at least one controllable heater, which is preferably controlled in dependence on the output signal of a flow meter of the feed channel arrangement.

With this development it is achieved that the vulcanization process begins appreciably only when the mold is completely filled with elastomeric material. Even before this moment you can pre-heat the mold space and thus reduce the total cycle time.

A further development of the invention is characterized in that the feed duct arrangement has a tempering device, which is preferably controlled in dependence on the output signal of a flow meter of the feed duct arrangement.

With this development it is achieved that you can control the entire supply of material depending on the level of the mold space. Thus, in critical areas of the filling process in which the elastomer material has to work into interspaces of the reinforcing insert, it is possible to supply somewhat slower elastomeric material and to supply elastomeric material at higher speeds in those regions of the mold space in which the flow conditions are simple.

The invention will be explained in more detail by means of exemplary embodiments with reference to the drawing. In this show:

1 : an axial view of a mold for the production of flexible discs, an external insulation largely omitted in part of a lid and parts of a mold feed head different transverse planes have broken away;

2 an axial section through the shape of 1 along the horizontal horizontal line there, additionally showing a supply device for not yet vulcanized elastomeric material and a device for evacuating the mold;

3 : a modified feed head for the shape of 1 and 2 also in axial half section;

4 : a similar view as 3 , in which again a modified variant of a feed head is shown;

5 : a schematic representation of a further modified feed head, wherein each feed channel is individually controlled in throughput;

6 a schematic representation of a controllable throttle for elastomeric material;

7 a partly broken away perspective view of a finished flexible disc with injection points, which lie in the peripheral surfaces of the flexible disc;

8th : a similar view as 7 wherein injection points of the flexible disc lie in the two end surfaces thereof; and

9 a variant of the embodiment of 2 ,

In 1 is with 10 overall designates an injection mold, which serves a reinforcing insert 12 for a flexible disc with an elastomeric material to overmold.

The injection mold is via a pipe 14 with the output of a pump 16 connected, which from a reservoir 18 not yet vulcanized elastomeric material 20 sucks and this provides under high pressure.

The output of the pump 16 is via a pressure relief valve 22 again with the reservoir 18 connected, as usual.

In the line 14 is a volume meter 24 arranged, which emits a signal, which is the total amount of emitted elastomeric material 20 equivalent. As usual, the volumeter can 24 be set to zero at intervals.

The injection mold 10 includes an upper mold part 10A and a lower molding 10B , which are formed in the embodiment considered substantially mirror images of each other. The moldings 10A . 10B are via a tongue and groove connection 30 . 32 connected with each other.

Unless otherwise described below, structures of the molded parts 10A and 10B with simple reference numerals (without attached letters A and B) described. It is understood that the symmetrical structure on the other molding is then also to be understood by these reference numerals.

The administration 14 is in the upper part of 1 only play schematically. In reality it concerns a line, which in addition with a trace heating 34 is provided. This allows the line 14 and to maintain their contents at a temperature above room temperature, yet still so low that the elastomeric material 20 not yet networked. Typically, for common elastomeric materials, this feed temperature can be in the range of 60 ° C while the crosslinking temperature for these materials is about 160 ° C.

The temperature control is carried out by using the output signal of one to the line 14 coupled temperature sensor 36 ,

The administration 14 Aligns with a central distribution channel 38 which slopes vertically down to near the bottom of a feed head 40 extends.

From the lower end of the distribution channel 38 go six circumferentially equally distributed horizontal star channels 42 from, from the radially outer end of each a riser channel 44 runs back in a vertical direction upwards.

How out 1 can be seen branches of the riser 44 at four different axial locations end channels 46-ij , (i = 1 to 4, different height, and j = 1 to 3 = different circumferential position), which up to the peripheral surface of the feed head 40 to run. The inclination of the end channels 46 (The indices ij are omitted, where necessary, omitted) is chosen so that their Ausmündungspunkte on the peripheral surface of the feed head 40 have an angular distance of about 15 °. Only one of the end channels (46-i2) runs so exactly radial direction.

The peripheral surface of the feed head 40 carries an insulating layer 52 , which is made for example of a thermally poorly conductive ceramic material or a thermally poorly conductive plastic material. In the insulating layer 52 there are short channel sections 48-i1 to 48-i3 , which are aligned continuations of the end channels 46-ij represent.

The outer surface of the insulating layer 52 is polished and fits in a tight sliding fit on the likewise cylindrical inner surface 56 from radially inner peripheral walls 58A . 58B which to the moldings 10A and 10B belong and injection channels 54-ij include the aligned continuations of the end channels 46-ij and the channel sections 48-ij represent.

The two molded parts 10A and 10B together limit a shape space 60 which has the shape of a rectangular-sectioned torus. On the outside radially outer peripheral wall 62A . 62B the molded parts 10A and 10B is an insulating layer 64 (only in 1 shown) applied. Similar also only in 1 shown insulating layers 66 are on the axial outer surfaces of the moldings 10A and 10B intended.

Inside the mold space 60 is the reinforcement mission 12 arranged, the six vertical coupling sleeves 68-1 to 68-6 having. Their axial ends are in depressions 70 positioned in the bottoms of the molded parts 10A . 10B are provided.

The coupling sleeves 68 are of loop packages 72 and 74 entwined whose arrangement will now be described in more detail below.

The coupling sleeves 68-1 and 68-2 are at their axial center of a loop package 72 embraced, which seen in the axial view roughly the shape of a rectangle whose narrow sides are formed by semicircles. Similar arrangements are known from belt drives. It should be noted that the coupling sleeves 68 are stationary and the loop packages 72 . 74 are very stiff.

The loop packages 74 each comprise two subpackets 74A and 74B , which on the end portions of the coupling sleeves 68-1 and 68-2 to sit.

The loop packages 72 and 74 comprise individual threads which are highly loadable in tension and embedded in a stiff somewhat elastic matrix, so that they can be handled in one piece.

Between the loop packages 72 and 74A . 74B are bearing discs 76 provided, which are made of elastomeric material.

Also elastomeric spacers 78 are located between the axially outer end surfaces of the loop packages 72 . 74A and 74B and a radial flange 80 , a collar sleeve 82 , which on the outside of the coupling sleeve 68 festgepunktet is, as with 82 indicated. Welding the collar sleeves 82 takes place under axial bias of the entire stack located between their flanges spacers 78 , Sling packages 74A . 74B , Bearing washers 76 and sling package 72 ,

Through the elastomeric bearing discs 76 and spacers 78 it is guaranteed that the loop packages 72 . 74A and 74B do not rub against each other and do not exert a notch effect on each other during torsional loads. The bearing washers 76 and 78 also ensure easy twistability of the reinforcing insert 12 about axes perpendicular to the symmetry axis of the reinforcement insert 12 are directed.

How out 1 can be seen, the coupling sleeves 68-2 and 68-3 through a pair of sling packages 74A and 74B connected. The coupling sleeves 68-3 and 68-4 again through a loop package 72 etc.

The reinforcing insert 12 Thus, on closer inspection, it has a threefold symmetry with respect to its symmetry axis, denoted S, neglecting the differences between the loop packages 72 and 74 and considering these as essentially mechanically equivalent, so does the reinforcing insert 12 six-fold symmetry.

How out 2 can be seen, is the bottom of the molding 10B an annular resistance heater 88 assigned. The temperature in the mold space 60 can through a sensor 90 be measured in the bottom of the lower molding 10B is admitted. It is understood that you also have several sensors over the walls of the moldings 10A and 10B can distribute to the temperature distribution in the mold space 60 better to grasp.

The feed head 40 is in contrast with a thermostat 92 in practice, which can be a weaker heater and heats when the ambient temperature is below the desired feed temperature for the unvulcanized elastomeric material (feed temperature). Ruling in the working space high temperatures, is the thermostats 92 but also capable of the feed head 40 to cool.

In the upper wall of the upper molding 10A are circumferentially equally distributed six vents 94 provided by a hard porous insert 96 are closed. The vents 94 are all with the suction side of a vacuum pump 98 connected.

The encapsulation of a reinforcing insert 12 is carried out as follows:
First, the reinforcement mission 12 in the lower molding 10B inserted so that the lower ends of its coupling sleeves 68 in the wells 70 to sit. Then the upper mold part 10A placed, where then the upper ends of the coupling sleeves 68 into the wells 70 of the upper molding 10A enter.

Now the connection to the vacuum pump 98 made, the feed head 40 gets into the central opening of the mold 10 inserted and the vacuum pump 98 gets set in motion. Already before has the thermostats 92 ensured that the elastomeric material, which is in the line 14 and in the distribution channel 38 , the food channels 44 and the end channels 48 has the desired feed temperature, which is desirable for rheological reasons, but still does not lead to any significant networking.

After connecting feed head 40 and injection mold 10 then becomes the pump 16 set in motion. From this point on, elastomeric material will be removed from the end channels 48 discharged and flows over the injection openings 54 into the interior of the mold space 60 , This movement takes place on the one hand by pushing (pressure in the line 14 ), on the other hand by train (vacuum pump 98 ). The elastomeric material then forms inside the mold cavity 60 a volume which is evenly distributed by the action of gravity and increasingly increases in the course of the filling process. A measure of how far the form space 60 already filled, forms the output of the volumeter 24 ,

Is the injection mold 10 completely filled, so the pressure in the elastomer material 20 increased again to also poorly accessible areas (around the reinforcement insert 12 around and in) completely filled with elastomeric material.

After a given Nachdrückzeit then the resistance heating 88 operated with greater power, up inside the anteroom 60 the desired vulcanization temperature of, for example, about 160 ° C is obtained. The crosslinking temperature is then maintained for a predetermined period of time, which ensures complete crosslinking of the elastomeric material in all areas of the mold cavity 60 is done.

After complete crosslinking of the elastomeric material can then be a complete joint disc of the injection mold 10 to be taken as they are in 7 is shown. In the upper half of the with 100 designated joint disc can be seen in the front third of the structure of the reinforcing insert 12 , On the inside surfaces you can see injection points 102 ,

For a better distribution of the elastomeric material in the mold space 60 to receive, was according to 7 also from the outer peripheral surface of the mold space 60 ago elastomeric material injected, as at external injection points 104 the flexible disc recognizable.

To make this possible, the outer peripheral wall needs 58 also be provided with passages, which are aligned with channels of another insulating layer and with end channels of another feed head. The arrangement would be substantially radially mirror-image to Elastomermaterialzufuhr to the inner peripheral wall 58 the molded parts 10A and 10B to think.

In 8th is a modified flexible disc 110 , which additionally inject gates 106 has on its axial end surfaces.

In order to produce such a flexible disc, you must also the bottoms of the moldings 10A and 10B and form their neighborhood with openings and channels over which unvulcanized elastomeric material is supplied.

These modifications can be made by transferring the measures described above with reference to the 1 and 2 have been designed.

For some applications, it is advantageous if the supply of unvulcanized elastomeric material to the mold space 60 strictly from the bottom up.

This can be done with a modified feed head 40 realize how he is in 3 is shown.

The channel end sections 40 now hang with circumferentially extending feed channels 44'-1 to 44'-4 together, all channel end sections 46 feed simultaneously with the same axial position. Each of the food channels 44 ' is via a radial star channel 42'i (i = 1 to 4) with the distribution channel 38 connected, in which an only schematically drawn control 108i (i = 1 to 4) is arranged. This can be a controllable valve.

In the embodiment considered here one has end channels 46 in four different axial positions, corresponding to four feed channels 44'-1 to 44'-4 and four star channels 42'-1 to 42'-4 , which can then be arranged at an angular distance of 90 °.

With the in 3 shown feed head 40 you can now selectively successively the end channels 48-1 to 48-4 provide with elastomeric material and the mold cavity fills accordingly 60 strictly from the bottom up. The elastomeric material is thus good for the various parts of the reinforcing insert 12 flow around.

Should this be desired for special reasons, also to impinge different levels Kanalendabschnitte simultaneously with elastomeric material, this is by appropriate control of the controls 108-i also possible.

4 shows a further modification in which the control of the elastomer output at the end channels 46 for each set circumferentially distributed dispensing channels can make different. This is for one set of axially aligned end channels 46-ij (i = 1 to 5, j = number of channels in the circumferential direction, eg 6 or n x 6) a control valve bank 108'-j provided that the connection between an end channel 46-ij and a star channel individually assigned to it 42-ij controls.

In this way, you can make the supply of elastomeric material in the mold space both in the axial direction and in the circumferential direction differently. This is advantageous for those products that are more symmetrical than rotational symmetry.

5 schematically shows the circuit diagram of a feed head 40 in which each of the end channels 46 can be applied separately with elastomeric material.

The arrangement of the end channels 46 is shown in a flat process. A single control valve bank 108 '' is to control the material flows to the individual end channels 46-ij intended. The control of the control valve bank 108 '' takes place electrically from a computer, not shown.

6 shows an embodiment of an electrically controllable elastomeric material control element 110 , This comprises a line section comprising at least one line winding 112 into a gutter 114 can be lowered when pressing on its top, as in 116 shown schematically. The reference number 116 thus stands for any controllable drive (in particular electromechanical or fluidic) that can generate the corresponding movement.

In the gutter 114 is a liquid cryogen 118 , z. B. a very low-viscosity oil, which is held by a refrigerator at a temperature of for example about -20 ° C.

Is the line section 112 partly in the liquid cryogen 118 dipped, as in 6 shown by dashed lines, so there is a "freezing" of the elastomeric material in this line section. The line section is thus closed.

Will the on the line section 112 exerted applied force, so the line section springs 112 back in through solid lines in 6 shown position back and heats up again.

Over the different pipe sections 112 the control valve bank 108 '' there is a bar 120 which individual small heaters 122 carries, each with an associated line section 112 work together. These may be HF coils that heat the material of the line section, preferably copper, by eddy currents. But it may also be an infrared radiator whose rays from the possibly correspondingly treated surface of the line sections 112 is absorbed.

In this way one obtains control of the elastomeric material flow to each of the end channels 46 which has no moving mechanical elements in the part cooperating with the elastomeric material.

It has been described above how to adjust the supply of elastomeric material to different areas of the mold space using control means differently. It is understood that when using a feed head with a single mold under always the same conditions even by solid structures can achieve a similar result, in particular by the geometry de channels through which the elastomer is promoted, in particular by providing bottlenecks whose Cross section and length can be specified, possibly also their temperature.

In 9 is z. B. a variant shown in which the mold space 60 is filled more or less symmetrically from above and below. These are star channels 42 ' halfway up the feed head 40 intended. The lower star channel 42 is not intended then. So then the climbing channels 44 fed at its center, and the elastomer material then flows evenly up and down, and then through the Endkanal pairs 46-2j and 46-3j such as 46-1j and 46-4j to emerge in substantially the same amount.

The embodiments described above can also be combined with each other. They can be provided for the entire injection mold or only for parts thereof.

Claims (15)

Mold for the production of flexible discs ( 100 ) comprising a reinforcing insert embedded in an elastomer composition ( 12 ), with at least two closely cooperating moldings ( 10A . 10B ), which together form a shape space ( 60 ), with positioning means ( 70 ) to the Precise insertion of the reinforcing insert ( 12 ) and with a feed channel arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ), via which moldable elastomeric material the mold space ( 60 ) can be supplied at different locations, characterized in that end sections of feed channels ( 46 ) substantially perpendicular to a wall ( 58 ) of the mold space ( 60 ) and with openings ( 54 ) of this wall ( 58 ) are substantially aligned. Mold according to claim 1, characterized in that the feed channel arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ) in a feed head ( 50 ) is formed and the feed head ( 50 ) from the mold space ( 60 ) through an insulating layer ( 52 ) is thermally isolated. Mold according to claim 2, characterized in that the insulating layer ( 52 ) is a ceramic layer or a plastic layer. Mold according to one of claims 1 to 3, characterized in that at least a part of the channels of the feed channel arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ) with tax means ( 108 ) is provided. Mold according to claim 4, characterized in that at least part of the control means ( 108 ) is formed as a throttle, which preferably at least partially through a channel or channel portion of the feed channel arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ) is formed. Mold according to claim 4 or 5, characterized in that at least part of the control means ( 108 ) is formed by controllable constrictions. Mold according to claim 6, characterized in that at least some of the controllable constrictions a hose valve or a cooling line ( 112 ). Mold according to one of claims 1 to 7, characterized in that the feed duct arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ) and / or control means ( 108 ) are formed so that at least a part of different food openings ( 54 ) of the mold space ( 60 ) are acted upon with elastomer material at the same throughput. Mold according to one of claims 1 to 7, characterized in that the feed duct arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ) and / or approximately provided control means ( 108 ) are formed and / or controlled so that the molding space ( 60 ) is filled substantially from bottom to top with elastomeric material. Mold according to claim 9, characterized in that in the feed channel arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ) a quantity meter ( 24 ) and the control for the control means ( 108 ) depending on the output signal of the flow meter ( 24 ) he follows. A mold according to any one of claims 1 to 10, wherein the reinforcing insert ( 12 ) Loop packages ( 72 . 74 ), characterized in that feed openings ( 54 ) of the mold space ( 60 ) with a subspace of the shape space ( 60 ), only a small part of the reinforcements ( 12 ) are taken. Mold according to one of claims 1 to 11, wherein the mold space ( 60 ) is substantially symmetrical to a median plane (M), characterized in that the parting plane between the two mold parts ( 10A . 10B ) with the plane of symmetry of the shape space ( 60 ) substantially coincides. Mold according to one of claims 1 to 12, wherein the molding space ( 60 ) has a multiple symmetry axis (S), characterized in that the feed channel arrangement has the same axis of symmetry (S). Mold according to one of claims 1 to 13, characterized in that it comprises at least one controllable heater ( 88 ), which preferably in dependence on the output signal of a flow meter ( 24 ) of the feed channel arrangement ( 14 . 38 . 42 . 44 . 46 . 48 . 54 ) is controlled. Mold according to one of claims 1 to 14, characterized in that the feed channel arrangement comprises a tempering device ( 34 . 92 ), which preferably in dependence on the output signal of a flow meter ( 24 ) of the feed duct arrangement is controlled.

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