Clamping units for injection molding machines for processing plastics

Abstract

In a clamping unit (F) of an injection molding machine for processing plastics, at least one movable mold carrier (10) capable of moving in the longitudinal direction (L-L) of the clamping unit is arranged on a machine base (14) and forms a mold clamping space (C) between itself and another mold carrier (12), in which a component of at least one periodically openable and closable injection mold (M) can be received. At least one linear guide (16) arranged on the machine base along the longitudinal direction serves to guide the at least one movable mold carrier when it moves in the longitudinal direction. The mold carrier is supported on the machine base and / or at least one linear guide by a load-bearing part (18), and above the at least one linear guide, the load-bearing part has an articulation area (20) for the at least one movable mold carrier, the articulation area being connected to the movable mold carrier by force fit or material bonding, and the stiffness of the articulation area in the longitudinal direction is greater than the stiffness in a direction transverse to the longitudinal direction. During operation of the injection molding machine, forces acting on the guide of the movable mold carrier are minimized by the oval cross section of the load-bearing portion and / or the articulation region, the minor axis of the oval extending in a direction transverse to the longitudinal direction of the clamping unit.

Description

[0001] Citations of Related Applications

[0002] This application is related to and claims the benefit of priority from German patent application 102020117168.4, filed on June 30, 2020, the disclosure content of which is hereby expressly incorporated in its entirety by reference. Technical Field

[0003] The present invention relates to a clamping unit of an injection molding machine for processing plastics and other plasticizable materials, the clamping unit comprising: a machine base configured to stably arrange the clamping unit; at least one movable mold carrier capable of moving in the longitudinal direction of the clamping unit and forming a mold clamping space between itself and another mold carrier, the mold clamping space being configured to receive at least one component of an injection mold that can be periodically opened and closed; at least one linear guide arranged on the machine base in the longitudinal direction of the clamping unit and configured to guide the at least one movable mold carrier during its movement in the longitudinal direction; at least one load-bearing component supporting the at least one movable mold carrier on at least one of the machine base and the at least one linear guide, the load-bearing component comprising a connection area for the at least one movable mold carrier above the at least one linear guide, the connection area being connected to the movable mold carrier by forced bonding or by material-to-material bonding, wherein the stiffness of the connection area in the longitudinal direction is greater than the stiffness in a direction transverse to the longitudinal direction. Background Art

[0004] The clamping unit of an injection molding machine is conventionally used as a component of the injection molding machine for opening and closing the injection mold in the longitudinal direction of the machine. To this end, a mold carrier (also called a movable mold carrier) configured for travel can be cyclically moved along the longitudinal direction of the clamping unit between an open position and a closed position of the injection mold by a drive mechanism (such as a closing mechanism and a corresponding drive). To enable this movement, corresponding linear bearings or linear guides are required, by which the movable mold carrier can also be supported by weight on the machine base.

[0005] US 4,948,358 A forms the basis for the preamble of claim 1 and discloses a clamping unit for an injection molding machine, the clamping unit having a mold carrier which is movable in the longitudinal direction of the clamping unit and which creates a mold clamping space between itself and another mold carrier for the purpose of receiving an injection mold. The movable mold carrier is supported on a linear guide on a machine base via a load-bearing component. Above the linear guide, the load-bearing component has a coupling region for the movable mold carrier, which is connected to the movable mold carrier and has a greater stiffness in the longitudinal direction than in a direction transverse to the longitudinal direction (see also WO 1998 / 041380 A1, Figures 1 to 2 ;DE 112016000803 T5, Figures 1 to 3 ; JP 2016-010885A, Figures 2 to 3 ).

[0006] DE 102007023337 A1 discloses a circular shape of a load-bearing part connecting a guide to a mold carrier. However, the exact shape of the cross section and its orientation are not obvious.

[0007] From WO 2009 / 051095 A1 ( Figures 3 to 4 ) a comparable clamping unit is known in which the coupling region is at a height of 20% to 70%, preferably 40% to 60%, of the height of the movable mold carrier and thus approximately at the height of the neutral axis with respect to thermal expansion (see also DE 102014002474 A1, Figure 1 ).

[0008] For the flow of influence, in JP 2014-104732 A, Figures 1 to 4 A method for producing a recess of material in a movable mold carrier is provided.

[0009] For a movable mold carrier, US2018 / 0207848 A1 discloses a load-bearing component integrated with the mold carrier.

[0010] US 2008 / 0175938 A1 discloses a clamping unit having a movable mold carrier which is supported over a relatively long distance on linear guides.

[0011] DE 102016119583 B3 discloses a device of this type, in which a movable mold carrier is supported on a linear guide via a bearing shoe, wherein an encapsulation is provided in the bearing shoe, by which lubricant released during movement of the mold carrier can be at least partially retained. Summary of the Invention

[0012] Taking the prior art as a starting point, the object of the present invention is to minimize the forces acting on the guide of a movable mold carrier during operation of an injection molding machine.

[0013] The features mentioned individually in the detailed description are combinable in a technically meaningful manner and can be supplemented by explanatory factual material from the description and details from the drawings, wherein further variant embodiments of the invention are indicated.

[0014] The clamping unit is arranged on the machine base for stably setting the clamping unit. At least one mold carrier is provided, which is movable in the longitudinal direction of the clamping unit and forms a mold clamping space with another mold carrier. A portion of at least one injection mold that can be opened and closed periodically can be received in the mold clamping space. A linear guide is also arranged on the machine base for guiding at least one movable mold carrier during movement in the longitudinal direction. A load-bearing component is provided for supporting the movable mold carrier on the linear guide or the machine base. The load-bearing component takes a form such that it is connected to the at least one movable mold carrier by forced bonding or by material-to-material bonding, so that a coupling area is formed above the at least one linear guide. This coupling area takes a form such that its stiffness in the longitudinal direction is greater than its stiffness in a direction transverse to the longitudinal direction. In the transition area from the mold carrier to the load-bearing part, this essentially forms a geometric connection which is configured and suitable for "rigidly" or "stably" absorbing forces arising in the vertical direction of the machine (e.g. gravity) and forces arising in the longitudinal direction of the machine (e.g. dynamic loads due to movements of the mold carrier and the injection mold) during operation of the injection molding machine, but is flexible in the transverse direction with respect to deformations arising, for example, due to thermal expansion of the injection mold during injection of plasticized material and subsequent cooling until the injection-molded part is released from the injection mold, or due to deformations under closing forces.

[0015] According to the invention, the load-bearing component and / or the coupling region are elliptical in shape, as this shape optimally ensures the introduction of forces while simultaneously ensuring the formation of a rigid and less rigid axis. In this arrangement, the major axis is oriented in the longitudinal direction of the machine, while the minor axis of the ellipse supports the deflection of the coupling region transversely to the longitudinal direction (preferably horizontally). This biomimetic design results in that forces generated in the longitudinal direction of the machine are appropriately and specifically transferred via the rigid coupling, while forces in the transverse direction remain "soft" within the system without excessively loading the longitudinal guides.

[0016] This specifically affects which forces (i.e. forces in the longitudinal direction and gravity) can be dissipated by the load-bearing component, while forces arising transversely to the longitudinal direction and therefore typically horizontal are transmitted in this direction, or at least to a significantly lesser extent, due to the "soft" formation of the connection area, with the result that these forces are not loaded onto the linear guide, or at least are loaded to a lesser extent.

[0017] At the same time, flexible elements are created, i.e., coupling areas that are soft transversely to the longitudinal direction (preferably in the horizontal direction) in order to absorb lateral extensions and dissipate them in a structurally optimized manner. By appropriately influencing the stiffness in a manner that depends on the desired direction of force introduction, the conflicts between gravity, dynamic forces, and thermal expansion forces can be optimally resolved.

[0018] Preferably, the stiffness of the coupling region in the vertical direction is greater than in the direction transverse to the longitudinal direction, with the result that advantageously, the weight forces are typically transferred entirely via the load-bearing components to the linear guide and into the machine base via the shortest route, which simultaneously reduces possible tilting moments.

[0019] In a preferred embodiment, the direction transverse to the longitudinal direction is preferably a horizontal direction lying approximately in a plane corresponding approximately to the longitudinal direction of the injection axis of the injection molding machine. This advantageously provides the basic prerequisites for a central introduction of force and also for force transmission or, in fact, reduced force transmission, since the arrangement thus lies with its central axis approximately in the region of the neutral axis of the mold.

[0020] In a preferred embodiment, the movable mold carrier is supported by a bracket and mounted on a linear guide, on which bracket the load-bearing parts and therefore the coupling area are mounted. On the one hand, this advantageously serves to support the movable mold carrier on the linear guide in the longitudinal direction over a relatively long area. At the same time, the forces are introduced into the machine base in a manner that is distributed over a relatively large surface. Depending on the construction, the bracket can additionally contribute to making the entire system essentially more rigid. Typically, since a plurality of linear guides (i.e. usually two linear guides) are arranged on both sides of the machine base, a suitably sized bracket creates a three-dimensional framework for introducing the forces into the machine base.

[0021] Preferably, the bracket is formed in multiple sections and / or has multiple load-bearing components, which advantageously allows the sections of the bracket to be adjusted or made more rigid relative to each other as needed, for example to increase stiffness in the longitudinal direction and / or reduce deflection transverse to the longitudinal direction. Similarly, height adjustment components may also be provided between the sections of the bracket.

[0022] For the purpose of better load transmission, it is likewise advantageous if the movable mold carrier is supported on the linear guide, advantageously with a plurality of supporting elements which are spaced apart from one another in the longitudinal direction of the clamping unit.

[0023] In principle, the coupling region can be formed in various ways. Preferably, it is formed by a material coupling, i.e., the load-bearing component and the movable mold carrier are connected to each other via a material-to-material bond, or are made of a single material, for example, by being manufactured in one piece or, in the exemplary embodiment, cast in one piece. However, because the material coupling allows for different levels of stiffness in the coupling region in the longitudinal direction of the clamping unit and in a direction transverse to the longitudinal direction of the clamping unit, it is advantageously possible, due to appropriate dimensioning, to ensure deflection in the transverse direction while also allowing for the desired introduction of dynamic loads and weight forces.

[0024] Preferably, at least one load-measuring element is provided on the load-bearing component and / or the coupling region, preferably in the form of a force or elongation measuring element and preferably arranged in the longitudinal and transverse directions. Advantageously, the forces in this region can thus be very well sensed, making it possible to detect any overload on the deformation element (such as the load-bearing component and / or the guide element).

[0025] More preferably, this load measuring element is arranged in the region of the material coupling and the load-bearing part connected thereto, which, due to the integral formation, can advantageously sense the forces there unambiguously and optimally at the compensating solid-state coupling, in particular by means of strain gauges.

[0026] In an alternative preferred embodiment, recesses in the material are provided in the movable mold carrier to reduce the stiffness of the coupling region transversely to the longitudinal direction (i.e., in the transverse direction). To this end, the movable mold carrier is supported on linear guides with spaced-apart support elements. These linear guides are arranged on both sides of the machine base, so that the recesses in the material are provided in the movable mold carrier between these linear guides. The recesses in the material advantageously reduce stiffness in a targeted manner at points where no forces are present or where the least possible forces are transmitted.

[0027] In principle, the coupling region can also be formed differently, in that either a positive joint is produced or a mechanical connection between the load-bearing component and the movable mold carrier is formed such that, advantageously from a structural point of view, different levels of rigidity are ensured.

[0028] Preferably, the connection area is located at a height of 20% to 70%, preferably 40% to 60%, of the height of the movable mold carrier. If the connection is formed approximately in the center of the movable mold carrier, then, in the event of thermal loads due to cyclic heating and cooling of the injection mold, this approximately corresponds to the neutral axis, where the smallest deformation occurs in the vertical direction when heat is introduced centrally. Therefore, this area is advantageously best suited for the connection between the mold carrier and the load-bearing component. The connection in this area also approximately corresponds to the height of the center of gravity of the injection mold, which can also help to reduce the risk of tilting during movement of the movable mold carrier.

[0029] In a preferred exemplary embodiment, in addition, a further mold carrier, which can typically be a mold carrier stationary relative to the machine base, can also likewise include a connection area of ​​this type, so as to advantageously also introduce gravity forces reliably into the machine base, but at the same time flexibly maintain forces resulting from movements or temperature expansions within the system.

[0030] It has been found to be advantageous if a height adjustment element is additionally provided for adjusting the height of the movable mold carrier relative to the linear guide. This height adjustment element can be activated in various positions and serves primarily to set the movable mold carrier to its optimal height, ensuring reliable guidance on the linear guide while simultaneously compensating for manufacturing tolerances of the associated components. In particular, this arrangement ensures that there is no contact with the tie rods or posts that connect the support of the closing mechanism to the stationary mold carrier and through which the closing force is transmitted. As a result, the tie rods or posts now serve solely as tension anchors.

[0031] This type of height adjustment element can act at different points on the clamping unit. It has been found that the preferred points are the coupling area itself, but also the arrangement between the load-bearing element and the carrier and / or between the carrier and the linear guide.

[0032] In another preferred exemplary embodiment, the bracket itself can also be composed of multiple parts, in which case the height adjustment element is arranged between these parts of the bracket.

[0033] To facilitate simple operation of the height adjustment component, in a preferred exemplary embodiment, the height adjustment component may have a preset height setting range using a manually actuable setting lever. Operation can then be comparable to headlamp range adjustment on a vehicle. By adjusting the setting lever, the height can be quickly and reliably adjusted upward or downward with manual intervention. This also allows for active control of changing and / or varying load conditions, even during operation.

[0034] Further advantages become apparent from the following description of preferred exemplary embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The invention is explained in more detail below with reference to a number of exemplary embodiments shown in the accompanying drawings, in which:

[0036] Figure 1 Shows a 3D view of the clamping unit,

[0037] Figure 1a and Figure 1b Shown in the area of ​​the movable mold carrier Figure 1 The enlarged details,

[0038] Figure 2 A clamping unit according to a further exemplary embodiment is shown in a three-dimensional illustration,

[0039] Figure 2a 、 Figure 2b as well as Figure 2c Show the basis Figure 2 an enlarged view of an exemplary embodiment of a movable mold carrier,

[0040] Figure 2d and Figure 2e Show the basis Figure 2 An enlarged view of the height adjustment component with a setting range,

[0041] Figure 3 A clamping unit according to a further exemplary embodiment is shown in a three-dimensional illustration,

[0042] Figure 3a 、 Figure 3b as well as Figure 3c Show the basis Figure 3 an enlarged view of an exemplary embodiment of a movable mold carrier,

[0043] Figure 3d Showing an enlarged view of the height adjustment feature on the bracket at the bottom,

[0044] Figure 4 A clamping unit according to another exemplary embodiment is shown in a three-dimensional illustration,

[0045] Figure 4a and Figure 4b Show the basis Figure 4 An enlarged view of the movable die carrier,

[0046] Figure 4c Show the basis Figure 4 An enlarged view of the movable die carrier,

[0047] Figure 5 Show the basis Figures 1 to 4 Side view of the clamping unit,

[0048] Figure 5a Shown along Figure 5 The line FF passes through the cross section of the die carrier,

[0049] Figure 6 A three-dimensional view of a clamping unit according to another exemplary embodiment is shown, and

[0050] Figure 7 Show the basis Figure 6 A view of the movable mold carrier supported on a machine base. DETAILED DESCRIPTION

[0051] The present invention will now be described in more detail by way of examples with reference to the accompanying drawings. However, the exemplary embodiments are merely examples and are not intended to limit the present invention to a specific arrangement. Before describing the present invention in detail, it should be noted that the present invention is not limited to the corresponding structural parts and corresponding method steps of the device, as these structural parts and methods may vary. The terms used herein are intended only to describe specific embodiments and are not intended to be used restrictively. In addition, when a singular or indefinite article is used in the specification or claims, it also indicates a plurality of these elements unless the overall context clearly indicates otherwise.

[0052] The figures show, in several embodiments, a clamping unit F of an injection molding machine for processing plastics and other plasticizable materials, such as powders or ceramics. In the figures, only the clamping unit of the injection molding machine is shown, and it is arranged on a machine base 14 and conventionally cooperates with an injection molding unit (not shown in the figures). In the injection molding unit, the plastic or plasticizable material is prepared, homogenized, and plasticized so that it can then be injected into the mold cavity of an injection mold M, which is received in a mold clamping space C of the clamping unit F. This type of construction for injection molding machines is well known, so no further details are required.

[0053] according to Figure 1 The clamping unit F is stably mounted on the machine base. Typically, the clamping unit F comprises at least one movable mold carrier 10, configured to move in the longitudinal direction LL of the clamping unit, and another mold carrier 12, preferably a stationary mold carrier fixedly connected to the machine base. Depending on the size of the machine, as in the present case, the movable mold carrier 10 can also take the form of a frame carrier, with a bearing structure behind the actual mold clamping plate.

[0054] In principle, the injection molding machine can also be a two-platen or three-platen machine, in which case, as in Figure 1In the example, an additional support 32 is provided at the left-hand end of the clamping unit for a closing mechanism S that can be actuated by a closing drive. The motorized drive of the closing mechanism is concealed beneath a cover of the support 32. However, in this exemplary embodiment, it can be seen that the closing mechanism is a toggle mechanism. However, in principle, other closing mechanisms, such as hydraulic, pneumatic, electromechanical, or indeed electric closing mechanisms and associated drives, can also be used.

[0055] When manufacturing an injection molded part, at the beginning of the injection cycle, the movable mold carrier 10 is transferred from the open position of the injection mold M to the closed position of the injection mold M by the closing mechanism S. Once the injection mold is closed in this way, the material plasticized by the injection molding unit (not shown in the figure) is injected into the mold cavity of the injection mold M. At this stage, the injection mold is typically heated to support the fluidity of the material when the plasticized material is injected. After injection, the plasticized material is cooled under back pressure until it has solidified enough to be discharged or released from the mold cavity as an injection molded part when the injection mold M is opened.

[0056] The opening and closing movements are performed with the aid of the closing mechanism S, and during this, the movable mold carrier 10 is guided along at least one linear guide 16, which is arranged on the machine base 14 in the longitudinal direction LL of the clamping unit F. In the exemplary embodiment, two linear guides 16 are provided, one on each side of the machine base 14, for the purpose of guiding the at least one movable mold carrier 10. In principle, however, more than two or indeed only one linear guide 16 can be provided.

[0057] During the injection molding cycle, parts of the injection mold M are cyclically opened and closed in order to cyclically produce the injection-molded parts. In the case of a two-platen machine between the movable mold carrier 10 and the further mold carrier 12, the forces and closing forces generated when opening and closing the injection mold M are transmitted between the further mold carrier 12 and the support 32 via tie rods 24. However, the use of tie rods 24 or columns as force transmission elements is not essential; in a known manner, force transmission elements can also be provided without tie rods, which allow free access to the mold clamping space C. The clamping unit F according to the present invention can also be constructed without tie rods.

[0058] In order to absorb the forces generated during the manufacturing process and transmit them to the machine base 14, a load-bearing component 18 is provided, which supports the at least one movable mold carrier 10 on the machine base 14 and / or the at least one linear guide 16. In the exemplary embodiment, the load-bearing component 18 transmits the forces via a bracket 26 and transmits them to at least one support element 34 (in the exemplary embodiment, a plurality of support elements 34), the components of which slide on the linear guides 16 and thus transmit the forces via the linear guides and into the machine base 14.

[0059] These forces are different forces generated during the injection molding process. On the one hand, there is the weight of the movable mold carrier 10 plus the weight of the injection mold M. In the case of relatively large machines, this can easily be a weight of 10 kN to 100 kN. In addition, dynamic forces are generated during the injection molding step due to the movement of the movable mold carrier 10 in the longitudinal direction LL from the open position to the closed position of the injection mold M (and vice versa). These dynamic forces must be reliably introduced into the machine base, if only to offset the possibility of the mold carrier tilting along with the mold.

[0060] However, since the injection mold M must be heated to a certain temperature before injection and then cooled again to cool the injection material, additional forces are generated. Due to the thermal expansion of the material, forces that can have a negative impact can arise, primarily in a direction transverse to the longitudinal direction LL of the clamping unit F. In the transverse direction, these forces particularly affect the linear guides, which are therefore subjected to additional loads and thus wear.

[0061] In order to introduce these forces into the machine base as far as possible without overloading the linear guides, which would be detrimental to the precision of the clamping unit and therefore the quality of the produced injection-molded part, and would also have a negative impact on the service life of the component, these forces are considered separately. The force of gravity should be transmitted to the machine base as directly as possible, and this also applies to dynamic forces. By contrast, forces resulting from thermal expansion can cause movements in the transverse direction (i.e., transversely to the longitudinal direction LL of the injection molding machine) via flexible elements in the clamping unit. Since some forces are directed away while others remain in the system, the initially generated conflict is resolved because, above at least one linear guide 16, the load-bearing component 18 has a connection region 20 for at least one movable mold carrier 10. The connection region 20 is connected to the movable mold carrier 10 by means of a positive connection or by a material-to-material bond and has a greater stiffness in the longitudinal direction LL than in a direction transverse to the longitudinal direction LL.

[0062] Figure 5A side view of a clamping unit F such as can be seen in essentially every exemplary embodiment is schematically shown. Figure 5a Shown along Figure 5 The line FF in FIG passes through a section of the movable mold carrier 10 . Here, a cross section of the load-bearing component 18 and the coupling region can be seen. The load-bearing component 18 and / or the coupling region 20 have an elliptical cross-section, wherein the minor axis of the ellipse extends in a direction transverse to the longitudinal direction LL of the clamping unit F, preferably in the horizontal direction. As a result, the load-bearing component 18 and the coupling region 20 are more flexible in this direction than in the direction of the major axis of the ellipse. This actually means that the coupling region 20 and the load-bearing component 18 are less rigid in the transverse direction than in the longitudinal direction LL. This biomimetic form has the following effect: deformations occurring in the transverse direction are elastically absorbed, while at the same time there is sufficient rigidity in the other spatial directions (i.e. in the longitudinal direction LL and vertically).

[0063] Typically, the clamping unit F is as follows Figure 1 In the illustrated orientation, the clamping unit extends horizontally in its longitudinal direction LL. Consequently, gravity forces act vertically, and to counteract these forces or the deflections caused by them, the injection molding machine must have a correspondingly rigid design. Rigidity and stability with respect to dynamic loads are also required, as these must be quickly and reliably incorporated into the machine base. In contrast, in the transverse direction, i.e., transverse to the longitudinal direction LL, the clamping unit, according to the invention, is flexible with respect to the forces resulting from deformation under closing force and, primarily, with respect to thermal expansion and the forces resulting from this expansion.

[0064] For this reason, the coupling region is configured to be more rigid both in the longitudinal direction and in the vertical direction than in a direction transverse to the longitudinal direction LL.

[0065] exist Figure 1 In the first exemplary embodiment, the load-bearing component 18 and the associated coupling area are fixedly cast on the movable mold carrier 10, i.e. there is a material-to-material bond. The coupling is made by a material coupling 22, but the coupling is of a structural form such that its stiffness in the longitudinal direction LL is greater than its stiffness in a direction transverse to the longitudinal direction LL. Specifically, Figure 1a and Figure 1b The material coupling 22 can be seen in FIG. 1 , wherein the movable mold carrier 10 is shown on its own and on the machine base 14 , respectively.

[0066] In this exemplary embodiment and also in the following exemplary embodiments, in each case a height adjustment component 30 is provided which is in a one-piece construction and therefore has a material-to-material bond in the connection between the load-bearing component 18 and the material coupling 22, which height adjustment component can be arranged only at the bottom between the load-bearing component 18 and the support element 34.

[0067] In order to compensate for the manufacturing tolerances of the relevant components, this type of height adjustment component is required. As is generally known in the prior art, a screw / threaded pin solution is used as the height adjustment component.

[0068] Figure 2 A clamping unit according to another exemplary embodiment is shown, wherein a carriage 26 is provided on the clamping unit, on which the movable mold carrier 10 is mounted. The movable mold carrier is supported on a linear guide 16 via the carriage. Figure 2a The load-bearing member 18 is an integral part of the lower bracket 26, which may have a Figure 2a However, even in accordance with Figure 2c In the case of an embodiment of the present invention, these parts can also be connected to each other to form a bracket. The single-piece construction provides greater rigidity, while in a multi-piece construction, the influence of heat on the linear guide 16 is smaller.

[0069] exist Figure 2 In the exemplary embodiment of the height adjustment part 30 is indicated at the top as a bolt / threaded pin solution. Figure 2d and Figure 2e It is clearly visible in the enlarged diagram of Figure 2e In contrast, the setting range can be provided by adjusting the screw. Figure 2d , the height adjustment component 30' can have setting limits, because in that case, a height setting range is provided that can be preset using a manually actuatable setting lever 42, however, the setting lever is movable only within a limited range. This type of configuration makes it easier for the user to quickly and easily perform height adjustments by moving the setting lever 42 to the left or right. This is comparable to the range adjustment of headlights in vehicles, where the height of the light beam is also set by a rotational movement.

[0070] By using a plurality of load-bearing elements 18, in particular in the embodiment using brackets 26, it is possible to direct the forces away from the machine base 14 in a manner distributed over a relatively long surface along the linear guide 16. For this purpose, the supporting elements 34 are spaced apart from one another in the longitudinal direction LL of the clamping unit F.

[0071] By way of example, Figure 2aAlso shown is the arrangement of at least one load-measuring element 36 (two load-measuring elements 36 in this exemplary embodiment). These load-measuring elements 36 are mounted on the load-bearing component 18, but they could also be mounted on the coupling region 20, either additionally or as an alternative. The load-measuring elements 36 preferably take the form of force or elongation measuring elements and are preferably arranged in the longitudinal and transverse directions. Consequently, the forces in this region can be very well sensed, making it possible to detect any overloads on the deformation elements (such as the load-bearing component 18 and / or the linear guide 16).

[0072] However, more preferably, as Figure 1 As shown, load measuring elements 36 are arranged in the region of the material coupling 20 and the load-bearing component 18 connected thereto. Due to the integral formation, forces can be optimally sensed at these compensating solid-state connections, in particular by means of strain gauges.

[0073] Figure 3 The exemplary embodiment of FIG shows another embodiment of the clamping unit F, in which the load-bearing component 18 is a separate part that is fixed to the bracket 26. Here, as in Figure 2 In a second exemplary embodiment, the bracket 26 may include a Figure 3a Multiple components or according to Figure 3c and in this case the height adjustment member 30 is arranged according to Figure 3d The height adjustment element is located between the bracket 26 and the linear guide 16 , meaning that, in contrast to other exemplary embodiments, the height adjustment element is located at the bottom. Furthermore, the load-bearing element 18 is screwed to the movable mold carrier 10 at the top, without any adjustment options. Here, too, the coupling region 20 is designed to be more rigid in the longitudinal direction LL than in a direction transverse thereto.

[0074] Figure 4 Another exemplary embodiment is shown, in which the load-bearing member 18 is an independent structural part, according to Figure 4a and Figure 4b , the independent structural part is screwed to both the bracket 26 and the movable mold carrier 10. Figure 4 Above the coupling region 20, a height adjustment element 30 is provided on the load-bearing element 18, but this can equally well be arranged at the bottom or between the bracket 26 and the linear guide 16. The more sections provided for the load-bearing element 18 and the bracket 26, the less thermal influence on the linear guide 16, and the fewer sections provided, the more rigid the bracket is and thus the more it transmits forces.

[0075] Additionally or alternatively, Figure 6 and Figure 7Within the scope of the fifth exemplary embodiment, the stiffness in the longitudinal direction LL can be increased because at least one recess 28 in the material is arranged transversely to the longitudinal direction LL according to Figure 7 The movable mold carrier 10 is preferably provided in the horizontal direction for the purpose of reducing the stiffness of the coupling region 20. It can be clearly seen that this makes the load-bearing component 18 and / or the coupling region 20 "softer" in the lower region, with the result that lateral deformations generated in the movable mold carrier 10 are transferred to a significantly smaller extent in the region of the linear guide 16.

[0076] However, in Figure 1 In a first exemplary embodiment, a connection is provided between the load-bearing component 18 and the movable mold carrier 10 by means of a material-to-material bond. Figures 2 to 4 In another exemplary embodiment, the connection is a positive joint, in that the parts are mechanically connected to each other.

[0077] These exemplary embodiments have in common that the connection region 20 is at a height of 20% to 70%, preferably 40% to 60%, of the height of the movable mold carrier 10 and is therefore approximately at the height of the neutral axis with respect to thermal expansion. As a result, the movable mold carrier 10 is connected approximately in the center, which, from a structural point of view, is a good location for introducing forces. The central connection point is the neutral axis with respect to thermal expansion and, in the case of heating with the injection mold M positioned in the center, serves for thermal expansion both at the bottom and at the top. As a result, in this plane, essentially only lateral expansions occur, which can be absorbed by the flexible load-bearing part 18 together with the connection region 20. At the same time, the approximately central connection also has the advantage of being connected approximately at the height of the center of gravity of the movable mold carrier 10 and the injection mold M, as a result of which tilting moments are also offset thereby.

[0078] In principle, another mold carrier 12 (eg according to Figure 6 ) can also take a form similar to the movable mold carrier 10, i.e., from a structural point of view, can also provide corresponding flexibility in the transverse direction. This is particularly true if it does not take the form of a stationary mold carrier. However, even in this case, this type of connection provided by the connection areas 20 with different levels of rigidity, depending on their orientation, can be advantageous in order to reliably and in a targeted manner divert the forces generated during the injection molding step.

[0079] As an alternative to the height adjustment elements shown, it is also possible to use wedges, the inclined surfaces of which slide above and below each other, in order in this way to adjust the height of the movable mould carrier relative to the linear guide.

[0080] According to the invention, a clamping unit is created in each case with which a linear guide can be provided for the purpose for which it is configured, namely to guide the movable mold carrier 10, wherein it is able to guide gravity and dynamic loads away from the machine base 14. Furthermore, it is largely unaffected by the forces occurring during operation.

[0081] Reference Number List

[0082] 10 Removable mold carrier

[0083] 12 Another mold carrier

[0084] 14 base

[0085] 16 Linear guides

[0086] 18 load-bearing components

[0087] 20 Connection Area

[0088] 22 Material connection parts

[0089] 24 tie rod

[0090] 26 brackets

[0091] 28 Recesses in the material

[0092] 30, 30' height adjustment parts

[0093] 32 Support

[0094] 34 Support elements

[0095] 36 Load measuring element ( Figure 2a )

[0096] 42 Setting lever

[0097] C Mold clamping space

[0098] F Clamping unit

[0099] LL longitudinal direction

[0100] M Injection Mold

[0101] S closing mechanism

Claims

1. A clamping unit (F) of an injection molding machine for processing plastics and other plasticizable materials, comprising: - a machine base (14) configured to stably arrange the clamping unit (F), - at least one movable mold carrier (10) movable in the longitudinal direction (LL) of the clamping unit (F) and forming a mold holding space (C) between itself and another mold carrier (12), the mold holding space being configured to receive components of at least one cyclically openable and closable injection mold (M), - at least one linear guide (16) arranged on the machine base (14) in the longitudinal direction (LL) of the clamping unit and configured to guide the at least one movable mold carrier (10) during a movement of the at least one movable mold carrier in the longitudinal direction (LL), - at least one load-bearing component (18) supporting the at least one movable mold carrier (10) on at least one of the machine base (14) and the at least one linear guide (16), the load-bearing component (18) comprising, above the at least one linear guide (16), a coupling region (20) for the at least one movable mold carrier (10), the coupling region being connected to the movable mold carrier by means of a positive connection or by a material-to-material bond, wherein the stiffness of the coupling region in the longitudinal direction (LL) is greater than the stiffness in a direction transverse to the longitudinal direction (LL), Characterized in that at least one of the load-bearing part (18) and the coupling region (20) has an elliptical cross-sectional shape, wherein the minor axis of the ellipse extends in a direction transverse to the longitudinal direction (LL) of the clamping unit (F).

2. The clamping unit according to claim 1, characterized in that The coupling region (20) has a greater stiffness in a vertical direction than in a direction transverse to the longitudinal direction (LL).

3. The clamping unit according to claim 1, characterized in that A direction transverse to the longitudinal direction (LL) is the horizontal direction.

4. The mold clamping unit according to claim 3, wherein: The horizontal direction lies in the plane of the longitudinal direction (LL).

5. The mold clamping unit according to claim 1, wherein: The movable mold carrier (10) is supported by a bracket (26) and mounted on the linear guide (16), the bracket being configured as the load-bearing component, or the load-bearing component (18) being mounted on the bracket.

6. The mold clamping unit according to claim 5, wherein: The bracket (26) has multiple parts.

7. The mold clamping unit according to claim 5, wherein: The bracket has a plurality of load-bearing components (18).

8. The mold clamping unit according to claim 1, wherein: The movable mold carrier (10) is supported on the linear guide (16) on a plurality of support elements (34) which are spaced apart from one another in the longitudinal direction (LL) of the clamping unit (F).

9. The mold clamping unit according to claim 1, wherein: The coupling region (20) is formed by a material coupling (22).

10. The mold clamping unit according to claim 1, wherein: At least one load measuring element (36) is arranged on at least one of the load-bearing component (18) and the coupling region (20).

11. The mold clamping unit according to claim 9, wherein: At least one load measuring element (36) is arranged on the material connection (22).

12. The mold clamping unit according to claim 1, wherein: At least one recess (28) is arranged in the movable mold carrier (10) transversely to the longitudinal direction (LL) and is designed to reduce the rigidity of the coupling region (20).

13. The mold clamping unit according to claim 1, wherein: The other mold carrier (12) is a mold carrier that is stationary relative to the machine base (14).

14. The mold clamping unit according to claim 1, wherein: The further mold carrier (12) comprises a coupling region (20) which is configured like the coupling region (20) of the movable mold carrier (10).

15. The clamping unit according to claim 1, wherein: A height adjustment component (30) is provided to adjust the height between components of the movable mold carrier (10) relative to the linear guide (16).

16. The clamping unit according to claim 15, wherein: The height adjustment member (30') has a preset height setting range using a manually actuatable setting lever (42).

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