Device for ejecting a mould comprising a chain with sliding links and an adjustment wedge

Abstract

The ejection device comprises: - a pushing device (14) movable in translation along a first axis (A1); - an ejection member (28) movable in translation along a second axis (A2) different from the first axis (A1); - a conversion device (26) connecting the pushing device (14) and the ejection member (28), the conversion device comprising a transmission chain (40) comprising at least two transmission links (42) movable in translation in a sliding direction. The ejection device further comprises an adjustment wedge (50) mounted on the pushing device (14), the adjustment wedge (50) comprising an adjustment surface (64) forming an adjustment angle (σ), the transmission chain (40) being mounted on the adjustment surface (64).

Description

TECHNICAL FIELD

[0001] The present invention relates to an ejection device for a mold for manufacturing a molded article in a mold cavity, said ejection device being for enabling the molded article to be ejected from the mold cavity, said device comprising:

[0002] - a pushing device able to translate along a first axis between a retracted position and an ejection position;

[0003] - at least one ejection element able to translate along a second axis different from the first axis between a retracted position and an ejection position,

[0004] at least one conversion device connecting the pushing device and the ejection element, the conversion device being arranged to move the ejection element along the second axis between its retracted position and its ejection position when the pushing device moves along the first axis between its retracted position and its ejection position, the conversion device comprising a transmission chain comprising at least two transmission links able to translate in a sliding direction relative to each other and relative to the pushing device and the ejection element. Such an ejection device allows for example to demold a molded article of complex shape, for example a part that is not flat or that has areas extending in one or more planes different from the plane perpendicular to the ejection direction or that has elements or undercut areas extending in a direction different from the ejection direction. Indeed, by providing an ejection device comprising for example an ejection rod that ejects the part along a first axis and another rod that forms the ejection element and ejects the part along a second axis, a part of complex shape can be ejected. BACKGROUND

[0005] Document EP-3210735 describes such an ejection device in which it is provided that the links of the transmission chain slide along a sliding surface at an angle to the first movement axis of the transmission chain, perpendicular to the sliding direction. This angle is chosen to synchronize the movement of the ejection element with the movement of the pushing device, in particular to accelerate or slow down the movement of the ejection element relative to the movement of the pushing device. Such a synchronization allows to adjust the movement of the ejection element relative to one or more other ejection rods also moved by the pushing device to demold other parts of the molded article so that the ejection element and the ejection rods reach their ejection positions simultaneously, while the movement paths of the ejection element and the other ejection rods between the retracted position and the ejection position are different.

[0006] However, this document does not describe a simple way to adjust this angle so that it can be easily changed when it is necessary to change the moment of the movement of the ejection element relative to the pushing device. SUMMARY

[0007] An object of the present invention is to overcome this drawback by providing an ejection device which allows the angle of sliding of the links relative to each other to be simply varied.

[0008] To this end, the present invention relates to an ejection device of the aforementioned type, further comprising at least one adjustment wedge mounted on the pushing device, said adjustment wedge comprising an adjustment surface forming an adjustment angle with respect to a direction substantially perpendicular to the first axis, the transmission chain being mounted on said adjustment surface so that the sliding direction is substantially parallel to said adjustment surface.

[0009] Thus, the adjustment wedge allows the sliding angle of the transmission links relative to each other to be easily adjusted by choosing the adjustment angle of the adjustment surface on which the transmission chain is slidably mounted. If it is necessary to change the sliding angle, what is needed is to provide another wedge having an adjustment surface forming the desired angle and to mount this new wedge on the pushing device. Thus, the sliding angle can be easily changed without having to modify the pushing device itself.

[0010] According to other optional features of the ejection device taken separately or in any technically feasible combination:

[0011] - the adjustment angle is negative to delay the movement of the ejection element relative to the pushing device, positive to accelerate the movement of the ejection element relative to the pushing device, or zero to make the ejection element move at the same speed as the pushing device;

[0012] - the transmission chain comprises a connecting link mounted so as to be able to move in translation on the transmission links, the ejection element being mounted so as to be able to move in rotation on said connecting link about an axis of rotation substantially perpendicular to the first and second axes;

[0013] - the connecting link comprises two deflection surfaces of the ejection element, said two deflection surfaces each extending from a central portion of the connecting link to an edge of said connecting link, the connecting link being oriented relative to the ejection element, said deflection surfaces allowing this orientation to vary as a function of the adjustment angle when the ejection element moves along the second axis between its retracted position and its ejection position;

[0014] - the two deflection surfaces of the connecting link are substantially symmetrical relative to each other with respect to the central portion of the connecting link;

[0015] - the connecting link is connected to the ejection element by a connecting member articulated to the connecting link and to the ejection element so as to allow the rotation of the connecting link relative to the ejection element;

[0016] - The drive chain includes an adjusting link that is translatably mounted on a drive link, the adjusting link including a positioning surface extending from the adjusting surface of an adjusting wedge, such that the sliding direction between the adjusting link and the drive link is substantially parallel to the adjusting surface;

[0017] - Each link of the drive chain includes at least two sliding surfaces configured to slide on the sliding surfaces of adjacent links, the sliding surfaces extending substantially parallel to the adjusting surface of the adjusting wedge;

[0018] - Each link of the drive chain is connected to at least one other link of the drive chain via at least one connecting element, said at least one connecting element being configured to allow translational movement of the links relative to each other; and

[0019] - The drive links are identical to each other. Attached Figure Description

[0020] Other aspects and advantages of the invention will become clear after reading the following description, given by way of example and with reference to the accompanying drawings, in which:

[0021] Figure 1 This is a schematic perspective view of a first mold component including an ejection device according to an embodiment of the present invention, with the ejection device in a retracted position.

[0022] Figure 2 yes Figure 1 A schematic perspective view of a portion of the ejection device;

[0023] Figure 3 yes Figure 2 A schematic perspective view of the adjusting wedge and adjusting chain link of the ejection device;

[0024] Figure 4 yes Figure 2 A schematic perspective view of the connecting links and ejection elements of the ejection device;

[0025] Figures 5 to 7 yes Figure 1 A schematic cross-sectional view of the first mold component, wherein the ejector device moves from the retracted position through the intermediate position to the ejected position; and

[0026] Figures 8 to 12 This is a schematic cross-sectional view of the first mold component, in which the ejector device is in the retracted position, and different movement paths of the ejector device are shown. Detailed Implementation

[0027] Reference Figure 1The document describes a mold 1 for producing a molded article 2, which may have any shape suitable for molding. Such a production mold 1 is, for example, an injection mold, a compression mold, a foaming mold, etc. More generally, a mold is used to impart a desired shape to material disposed in a mold cavity having the desired shape of the article to be molded.

[0028] The molded article 2 is, for example, a motor vehicle part. More specifically, according to the embodiment shown in the figures, the molded article 2 includes a main surface 4 and an undercut portion 6 relative to the main surface, that is, a portion of at least one surface of a complementary molding element that cannot be demolded by simply removing the two mold parts and needs to be movable in a direction different from the direction in which the two mold parts are removed.

[0029] The production mold 1 includes a first component 8 and a second component (not shown for simplicity). The first component 8 and the second component are movable relative to each other between an open position and a closed position. In the open position, the first component and the second component are spaced apart from each other. In the closed position, the first component and the second component are moved toward each other to define a closed main mold cavity. The shape of the main mold cavity is complementary to the main surface 4 of the molded article to be produced. The movement from the closed position to the open position occurs along the opening direction D shown in the figure. The first component 8 includes a molding surface 10, which, together with the molding surface of the second component, defines the main mold cavity when the first component and the second component are in the closed position.

[0030] The main surface 4 of the molded article 2 is designed to be separable from the molding surface 10 by movement of the molded article in a single ejection direction, for example, parallel to the opening direction D. Therefore, the main surface 4 need not be flat and can have any shape that allows demolding by moving the molded article 2 in the ejection direction. Thus, according to the embodiment shown in the figures, the main surface 4 includes a first portion 5 substantially perpendicular to the opening direction D and a second portion 7 inclined relative to the first portion 5. It should be noted that the main mold cavity can also be configured to form elements extending from the main surface 4, such as ribs, provided that these elements can also be separable from the main mold cavity by moving the molded article 2 in the ejection direction.

[0031] According to the embodiment shown in the accompanying drawings, the main mold cavity is in fluid communication with an auxiliary mold cavity defined by the molding surface 10 of the first component 8 and the complementary molding surface 12 provided by the ejection device according to the invention, which will be described later. The shape of the complementary mold cavity is complementary to the undercut portion 6 of the molded article 2. The main mold cavity and the auxiliary mold cavity together form the mold cavity of the production mold 1. It can be understood that multiple auxiliary mold cavities may be provided depending on the shape of the article to be molded.

[0032] Mold 1 is, for example, an injection mold configured to inject plastic material into a mold cavity at a predetermined pressure. For this purpose, production mold 1 includes all means for performing and controlling this injection and the formation of the part, such as one or more injection nozzles for the plastic material, means for regulating the temperature of the mold cavity, means for actuating and moving a first part and a second part of production mold 1, etc. Since such means are known, they will not be described in more detail here.

[0033] The production mold 1 includes an ejection device configured to facilitate the removal of the molded article 2 from the production mold after its production. Once the molded article 2 has been produced, the first and second parts of the mold are moved to the open position. Then, as... Figure 1 and Figure 5 As shown, the molded article 2 abuts against the molded surface of the first component 8, and as Figure 7 As shown, the ejector device is configured to move the molded article 2 away from the molding surface 10 so that the molded article 2 can be clamped and removed from the production mold. It should be noted that the ejector device can be actuated during the opening of the mold 1, so that the ejection of the molded article 2 does not have to begin when the mold is already in the open position.

[0034] The ejection device includes a pushing device 14, which is capable of pushing within the first component 8. Figure 1 and Figure 5 The retraction position shown is the same as Figure 7 The ejection positions shown are translated along the first axis A1. The first axis A1 extends in the ejection direction and is, for example, substantially parallel to the opening direction D, such that in the ejection position, the molded article 2 moves away from the molding surface 10 into the space between the first mold component 8 and the second mold component.

[0035] The pushing device 14 includes at least one ejector plate 16, which is translatably disposed in the space 18 of the first component 8 along the first axis A1. In the retracted position, the ejector plate 16 is disposed in the upstream portion 20 of the space 18 (i.e., the portion of the space 18 furthest from the molding surface 10), and in the ejected position, the ejector plate 16 is disposed in the downstream portion 22 of the space 18 (i.e., the portion of the space 18 closest to the molding surface 10).

[0036] The actuating device 14 also includes an actuating element 24 movably connected to the ejector plate 16, which is connected to the conversion device 26, which is connected to the ejector element 28.

[0037] Ejector element 28 is translatable along a second axis A2, which is different from the first axis A1. According to the embodiment shown in the figures, ejector element 28 is a movable block with a complementary molding surface 12. Thus, in the retracted position, the block is positioned in the first component 8 such that the complementary molding surface 12 extends relative to and together with the molding surface 10 of the first component 8, defining a complementary cavity. The movable block includes an actuating end 30. Ejector element 28 also includes an actuating rod 31, which is connected to the actuating end 30 of the movable block via its downstream end and extends along the second axis A2. The upstream end of the actuating rod 31 is connected to a conversion device 26, which will be described later. It should be noted that the actuating rod 31 can be integrally formed with the movable block. However, providing a movable block and actuating rod 31 formed by two separate parts improves the adaptability of ejector element 28 to different molds, which will be described later.

[0038] The second axis A2 forms an angle α with the first axis A1. The value of angle α is selected according to the shape of the molded article. More specifically, in the case where the molded article includes an undercut region 6, angle α depends on the distance required to move the movable block out of the undercut region 6 during the ejection of the molded article 2, which will be described later.

[0039] Therefore, when the pushing device 14 is in the retracted position and the ejected position via the conversion device 26, the ejecting element 28 can move between the retracted position and the ejected position. The conversion device 26 is configured to convert the movement of the pushing device 14 along the first axis A1 into the movement of the ejecting element 28 along the second axis A2, which will now be described.

[0040] The conversion device 26 includes a guide element 33 extending from space 18 to molding surface 10 in the first mold component 8. This extension follows a path along a first axis A1 in space 18 and along a second axis A2 in a portion of the first mold component 8 extending between space 18 and molding surface 10. The guide element 33 includes a first segment 32, formed, for example, by two contours 34, extending along the first axis A1 into space 18 and defining, for example, a first guide groove or slider between the two contours 34. The guide element 33 also includes a second segment 36, formed, for example, by a tube, extending along the second axis A2 in the first component 8 between space 18 and molding surface 10, and defining, for example, a second guide groove or slider within an internal volume of the tube. The guide element 33 is fixed relative to the first mold component 8.

[0041] It should be noted that the ejector plate 16 is translatable relative to the guide element 33. For this purpose, the ejector plate 16 includes recesses 38 configured to receive two contours 34 of the first segment 32. These recesses 38 are slidable around and along the first segment 32, thereby allowing the ejector plate 16 to move between its retracted position and its ejected position, which will be described later.

[0042] The conversion device 26 also includes a drive chain 40 connected on one side to the pusher 14 and on the other side to the ejector element 28. The drive chain 40 includes at least two interconnected drive links 42 that are translatable relative to each other. The translation of the drive links 42 occurs along sliding surfaces 44, which are substantially parallel to each other. The drive links 42 are also translatable relative to the pusher 14 and the ejector element 28. For this purpose, each drive link 42 includes at least two sliding surfaces 44, one forming a translational surface with an adjacent drive link 42, and the other forming a translational surface with an adjacent drive link 42, or with an adjusting link 46, or with a connecting link 48, as will be described later. The length of the sliding surfaces 44 is such that the drive links 42 do not disengage from each other when the ejector moves between its retracted and ejected positions. Additionally, these sliding surfaces 44 have sufficient length to transmit thrust from the ejector plate 16 to the ejector element 28.

[0043] Each sliding surface 44 forms an angle β with the direction perpendicular to the first axis A1, such as Figures 8 to 12 As shown. By adjusting the angle β relative to the first axis A1, the advance or delay of the movement of the ejector element 28 relative to the movement of the pusher 14 can be adjusted, which will be described later.

[0044] The number of drive links 42 in the drive chain 40 depends on the path followed by the drive links 42 in the guide element 33, and is configured such that the drive chain 40 connects the pusher 14 to the ejector element 28. More specifically, the drive chain 40 connects an adjusting wedge 50, integrated with the ejector plate 16, to the upstream end of the actuator rod 31. The adjusting wedge 50 will be described later.

[0045] Therefore, the drive chain 40 may include: more than two drive links 42, wherein the two end drive links are respectively connected to the adjusting link 46 and the connecting link 48; and a plurality of drive links connected to at least one intermediate drive link of the two end drive links or continuously connected to each other to form a drive chain 40 from the adjusting link 46 to the connecting link 48.

[0046] All drive links 42 are identical, that is, whether they are end drive links or intermediate drive links, they have the same shape and structure.

[0047] Various shapes of drive links 44 are conceivable. One of these shapes will be described below, and for other examples of possible shapes, those skilled in the art may refer to EP-3210735. Whatever shape is chosen, it must be adjusted so that drive links 42 can engage with each other and with guide element 33 throughout the entire path of movement of drive links 42, thereby guiding drive links 42 within guide element 33 throughout the entire path of movement.

[0048] For this purpose, each drive link includes at least one guide surface 52, which is configured to engage with a first guide groove and a second guide groove of a first segment 32 and a second segment 36 of a guide element 33 throughout the entire travel path of the drive link 42 with the guide surface 52. "Engagement" means that the guide surface 52 slides, slides, and / or rolls in contact with a guide groove throughout the entire travel path of the drive link 42 with the guide surface 52. Thus, when the drive link 42 is in the first segment 32 of the guide element 33, the guide surface 52 contacts at least one surface of the first guide groove, and when the drive link 42 is in the second segment 36, the guide surface 52 contacts at least one surface of the second guide groove. According to the embodiment shown in the figures, the guide surface 52 is formed by a roller 54, the diameter of which is substantially equal to the width of the guide groove. For example, the roller 54 is mounted on a shaft extending from and fixed relative to the drive link 42. For example, the shaft has a substantially circular cross-section. The cylindrical outer peripheral surface 54 forms a guide surface by sliding contact with the wall of a guide groove at at least two points on the surface. In one embodiment, each drive link includes two rollers 54 configured to mate with one of the profiles 34 or tubes forming the first segment 32 and the second segment 36, respectively. In one embodiment, the rollers 54 may also rotate relative to the drive link, such that the guide surface 52 may also roll on the wall of the guide groove. This ensures efficient guidance of the drive link in the guide element 33, thus avoiding the risk of ejection device blockage or jamming due to the drive link 42 becoming stuck in the guide element 33. It should be noted that the guide surface 52 may be defined directly by the shape of the drive link 42 without the need for additional rollers, as this shape can be configured to define sliding contact with the guide element 33.

[0049] As previously described, to ensure translational movement of the links relative to each other and relative to the adjusting link 46 and the connecting link 48, each drive link 42 includes two sliding surfaces 44, each formed by a wall of the drive link 42. The walls forming the sliding surfaces 44 can be arranged in different ways, as long as they are complementary and allow translational movement relative to each other. According to the embodiment shown in the figures, each drive link 42 has an S-shaped cross-section in a plane perpendicular to the first axis A1 and the second axis A2. Therefore, each drive link 42 includes two outer branches and one inner branch, which are connected to each other to define two slots, each slot extending between the inner branch and one of the outer branches and opening in two opposite directions. The opposing walls of the outer and inner branches each define a sliding surface 44. Thus, each drive link has six sliding surfaces 44 defined by the opposing walls of each slot and the outer surfaces of the outer branches of the drive link 42. This implementation ensures a robust connection between the drive links 42 because each drive link 42 is held in two slots of the adjacent link, including the end drive links, which will be described later. Each sliding surface 44 extends in the sliding direction, and all sliding surfaces 44 are parallel to each other.

[0050] according to Figure 2In the illustrated embodiment, the drive links 42 are also connected in pairs by connecting elements 56. Each connecting element 56 is hinged to two drive links 42 to allow translational movement of the two drive links 42 connected to each other, while preventing the drive links 42 from disengaging from each other, particularly when the drive chain 40 is not installed in the production mold. In other words, the connecting element 56 is adapted to allow the sliding surfaces 44 of the two drive links 42 to slide over each other while keeping the drive links 42 from separating when the drive chain is manipulated outside the mold (e.g., when it is assembled and installed into the mold). Such a connecting element 56 is formed, for example, by a link comprising two opposing ends 58, each hinged to a drive link 42 connected by the connecting element 56. More specifically, each end 58 includes, for example, an opening, which is, for example, elliptical in shape, to rotatably receive a circular shaft carrying a roller 54 of the drive link 42. A gap is allowed between the shaft and the connecting element to allow movement of the links relative to each other. According to one embodiment, the outer surface of end 58 also forms a guide surface 52 for the drive link 42 in the guide member 33, as described above. In one embodiment, the connecting member 56 is formed of a flexible member connected at each end to a drive link 40 connected by the connecting member 56. It will be understood that by providing protruding pins on both sides of the links of the drive chain 40, the drive link 42 can be connected to an adjacent drive link 42 via the connecting element 56 and to another adjacent link via another connecting element 56. Such a connecting element 56 is described in FR-3065388, and those skilled in the art will be able to refer to it to see other examples of possible embodiments.

[0051] As previously described, the drive chain 40 includes two end drive links 42, one of which is connected to the adjusting link 46 and the other to the connecting link 48. More specifically, the end drive link 42 closest to the ejector plate 16 is connected to the adjusting link 46, and the end drive link 42 closest to the actuating rod 31 is connected to the connecting link 48.

[0052] Adjusting link 46 ensures the engagement of the drive chain 40 via adjusting wedge 50 with the drive device 14. For example... Figure 3As shown, the adjusting link 46 has the shape of half of the drive link 40. Therefore, the adjusting link 46 has a semi-S-shape on one side formed by an outer branch 58 and an inner branch 60, which define a slot 62 between them. The slot 62 allows the adjusting link 46 to engage with the end drive link 42 and to translate relative to the end drive link 42 in the same manner as the two drive links 42 engage with each other. Thus, the outer branch 58 is inserted into the slot of the end drive link 42, and the slot 62 receives the outer branch of the end drive link 42. Therefore, the outer branch 58 and the inner branch 60 define three sliding surfaces 44a, 44b, 44c that slide in contact with the three sliding surfaces 44 of the end drive link 42. As described above, the adjusting link 46 can also be connected to the end drive link 42 via a connecting element 56. On the side of the inner branch 60 opposite to the slot 62, the adjusting link 46 includes a positioning surface 45 parallel to the sliding surfaces 44a, 44b, 44c of the adjusting link 46. The positioning surface 45 is configured to be applied to the adjusting surface 64 of the adjusting wedge 50, which will now be described.

[0053] The adjusting wedge 50 is reversibly mounted on the pushing device 14, meaning that the adjusting wedge 50 can be removed from the pushing device 14 to be replaced by another adjusting wedge. For this purpose, the adjusting wedge 50 is, for example, by... Figure 2 The screw 66 shown is screwed onto the actuating element 24. When the adjusting wedge 50 is mounted on the actuating element 24, the adjusting surface 64 is set to form an adjusting angle σ relative to a direction substantially perpendicular to the first axis A1, as shown. Figure 2 and Figure 3As shown. Therefore, by applying the positioning surface 45 of the adjusting link 46 to the adjusting surface 64, the positioning surface 45 of the adjusting link 46 needs to form an angle equal to the adjusting angle σ with respect to a direction substantially perpendicular to the first axis A1. When the sliding surfaces 44a, 44b, 44c of the adjusting link 45 and the sliding surface 44 of the drive link 42 are parallel to the positioning surface 45 of the adjusting link 46, these sliding surfaces 44 therefore form an angle equal to the adjusting angle σ with respect to a direction substantially perpendicular to the first axis A1. In other words, angle β is equal to the adjusting angle σ, and the sliding direction is parallel to the adjusting surface 64. Therefore, by selecting the value of the adjusting angle σ, the angle β formed by the sliding surface 44 of the drive chain 40 relative to the direction substantially perpendicular to the first axis A1 is adjusted, and the angle β can be modified by changing the adjusting angle σ using another adjusting wedge instead of the adjusting wedge 50. Therefore, by changing a single component of the ejector device, the behavior of the ejector device when moving between the retracted position and the ejected position can be changed to adapt it to the molded article 2 to be produced, which will be described later. It is particularly easy to change the adjusting wedge 50 to another adjusting wedge with a different adjusting angle, because it is enough to unscrew the adjusting wedge 50 from the actuating element 24 and screw on another adjusting wedge with the desired adjusting angle.

[0054] The positioning surface 45 is applied to the adjusting surface 64 such that the adjusting link 46 is connected to the adjusting wedge 50 via the connecting element 56. The connecting element 56 prevents relative movement between the adjusting link 46 and the adjusting wedge 50. Figure 2 As shown. For this purpose, the axis of the adjusting wedge 50 receiving the end 58 of the connecting member 56 is, for example, elliptical in shape, substantially complementary to the elliptical opening of the connecting member 56, in order to prevent relative movement between the adjusting link 46 and the adjusting wedge 50. For this purpose, the adjusting wedge 50 and the adjusting link 46 include at least one roller 54, as described above with reference to the drive link 42. The roller 54 also forms a guide surface 52, also as described above with reference to the drive link 42.

[0055] More specifically in Figure 4The connecting link 48 shown connects the drive chain 40 to the ejector element 28, and more specifically to the actuating rod 31. In particular, it is configured to allow the actuating rod 31 to adapt to a selected adjustment angle σ. Similar to the adjusting link 46, the connecting link 48 has a semi-S-shape on one side formed by an outer branch 68 and an inner branch 70, which define a slot 72 between them. The slot 72 allows the connecting link 48 to engage with the end drive link 42 and to translate relative to the end drive link 42 in the same manner as the two drive links 42 engage with each other. Thus, the outer branch 68 is inserted into the slot of the end drive link 42, and the slot 72 receives the outer branch of the end drive link 42. Therefore, the outer branch 68 and the inner branch 70 define three sliding surfaces 44e, 44f, 44g that slide in contact with the three sliding surfaces 44 of the end drive link 42. As described above, the connecting link 48 can also be connected to the end drive link 42 via the connecting element 56. On the side of the inner branch 70 opposite to the slot 72, the connecting link 48 includes two deflecting surfaces 74 of the ejector element 28. These two deflecting surfaces 74 extend on both sides of the central portion 76 of the connecting link 48 and converge from the central portion 76 toward the edge of the inner branch 70. Converging toward the edge of the inner branch 70 means that each deflecting surface 74 is inclined between the central portion 76 and the corresponding edge of the inner branch 70, such that the connecting link 48 has a substantially triangular shape on the side of the inner branch 70 opposite to the slot 72. Therefore, each deflecting surface 74 forms an angle θ with the sliding surface 44e formed by the inner branch 70, the deflecting surfaces 74 forming two sides of the triangle, and the third side of the triangle being formed by the sliding surface 44e. The angle formed by one deflecting surface 74 is equal to the angle formed by the other deflecting surface 74, such that the two deflecting surfaces 74 are substantially symmetrical to each other with respect to the central portion 76. The angle θ is also substantially equal in absolute value to the maximum value envisioned for the selected adjustment angle σ. Therefore, the envisioned maximum value corresponds to the adjustment wedge 50 with the maximum adjustment angle, which can be used with this production die or other production dies, since the same ejection device can be used with different dies. Thus, the connecting link 48 can be used with all the adjustment wedges 50 envisioned for the die. In one embodiment, the angle θ is substantially equal to 35°. The inclined deflection surface 74 releases space below the ejector element 28, allowing it to be oriented at the selected adjustment angle σ by rotation relative to the connecting link 48.

[0056] In one embodiment, the central portion 76 itself forms a deflection surface substantially parallel to the sliding surfaces 44e, 44f, and 44g, such that the connecting link 48 has a trapezoidal cross-section, rather than a triangular cross-section, on the side of the inner branch 70 opposite the slot 72. However, in another embodiment, the central portion 76 forms a curved surface with a radius concentric with the axis of the carrying roller 54. Such a curved shape facilitates the rotation of the ejector element 28 relative to the connecting link 48, which will now be described.

[0057] The connecting link 48 is rotatable relative to the actuating rod 31 (e.g., relative to the connector 78 integrated with the actuating rod 31 and fixed to the actuating rod 31 by screws 80), such as Figure 4 As shown. According to one embodiment, the actuating rod 31 and possibly the connecting member 78 do not directly contact the deflecting surfaces 74 and 76 of the connecting link 48 in order to limit friction between the ejector rod 31 and the connecting link 48. The connecting link 48 can be oriented relative to the ejector rod 31, and the deflecting surface 74 allows such orientation to depend on the value of the adjustment angle σ, which will be described later. Therefore, regardless of the value of the adjustment angle σ, the connecting link 48 ensures the transition between the drive chain 40 and the actuating rod 31, thereby ensuring the movement of the actuating rod 31 along the second axis A2 regardless of the value.

[0058] The connection between the connecting link 48 and the connecting member 78 is provided, for example, by the connecting element 56 as described above. For this purpose, the connecting member 78 and the connecting link 48 include at least one pin extending from the connecting link 48 and the connecting member 78, on which a roller 54 can be mounted, as described above with reference to the drive link 42. The roller 54 also forms a guide surface 52, also as described above with reference to the drive link 42.

[0059] The ejection device may also include one or more ejection rods 82 extending in a direction parallel to the first axis A1, such as Figure 1 and Figures 5 to 7 As shown. One end of the ejector rod 82 is integrated with the ejector plate 16, and its other end is flush with the molding surface 10 in the retracted position of the ejector device, forming part of the molding surface 10, as shown. Figure 1 and Figure 5 As shown. One or more ejector rods 82 are configured to allow the molded article 2 to be ejected in the direction the mold is open, which will now be described.

[0060] The operation of the above-described ejection device will now be described.

[0061] During the molding of the article, the mold is in a closed position and the ejector is in a retracted position. In this retracted position, the ejector plate 16 is located in the upstream portion 20 of the space 18, the ejector rod 82 is flush with the molding surface 10, and in this retracted position, according to the embodiment shown in the figure, the ejector element 28 defines an auxiliary mold cavity with the first component 8 through its auxiliary molding surface 12.

[0062] Once the article has been produced, the mold is opened by moving the first mold component and the second mold component away from each other in the opening direction D. During or after the opening, the ejector device is actuated from its retracted position to its ejected position.

[0063] Therefore, the ejector plate 16 is moved into the space 18 towards the downstream portion 22 of the space 18, as... Figure 6 As shown. During this movement, the ejector plate 16 moves along the first axis A1 by sliding around a first section 32 of the guide element 33, which enters a recess 38 of the ejector plate 16 provided for this purpose.

[0064] The movement of the ejector plate 16 causes the ejector rod 82 to move in a direction parallel to the first axis A1, thereby causing the molded article 2 to move away from the molding surface 10 in that direction, such as... Figure 6 As shown.

[0065] In addition, the movement of the ejector plate causes the adjusting wedge 50 to move along the first axis A1, which in turn causes the drive chain 40 to move within the guide element 33, and the drive chain 40 causes the ejector element 28 to move.

[0066] like Figure 1 As shown, in the retracted position, the drive link 42 is initially located in the first segment 32 of the guide element 33. Movement of the ejector plate 16 causes the link 42 to move along the first axis A1 and gradually engage the second segment 36, changing direction to move along the second axis A2, as... Figure 6 As shown. This change of direction can be achieved by the sliding surfaces 44 of the transmission chain links 40 sliding relative to each other.

[0067] The movement of the link along the second axis A2 causes the actuator rod 31 and the movable block to move along that axis. Due to the angle α between the first axis A1 and the second axis A2, the movement of the actuator rod 31 causes the movable block to slide out of the undercut region 6, as... Figure 6As shown, this allows the area to be demolded. It should be noted that by adjusting the value of the adjustment angle σ and thus the angle β formed by the sliding surface 44, the movement of the movable block out of the undercut region 6 relative to the pusher 14 can be delayed or accelerated. That is, for the pusher 14 moving along the first axis A1 at a given speed, in the case of accelerated movement, the movable block will move at a higher speed than the given speed, or in the case of delayed movement, it will move at a lower speed than the given speed. By accelerating or delaying the movement of the movable block relative to the pusher 14, the movement of the movable block can be synchronized with the movement of one or more ejector rods 82, so that even if the ejector strokes are different, the movable block and the ejector rods 82 reach the ejection position simultaneously.

[0068] exist Figure 8 In this configuration, angle α is approximately equal to 30° and adjustment angle σ is zero, meaning the adjustment surface 64 of the adjusting wedge 50 extends substantially perpendicular to the first axis A1. In this case, the movable block moves at the same speed as the pushing device 14.

[0069] exist Figure 9 In this configuration, angle α is approximately 35°, and adjustment angle σ is approximately -35°. Under these conditions, the movable block moves at a slower speed than the moving speed of the pushing device 14.

[0070] exist Figure 10 In this configuration, angle α is approximately 20°, and adjustment angle σ is approximately -40°. Under these conditions, the movable block moves at a slower speed than the moving speed of the pushing device 14.

[0071] exist Figure 11 In this configuration, angle α is approximately 15°, and adjustment angle σ is approximately 20°. In this case, the movable block moves at a speed faster than the moving speed of the pushing device 14.

[0072] exist Figure 12 In this configuration, angle α is approximately 15°, and adjustment angle σ is approximately 30°. In this case, the movable block moves at a speed faster than the moving speed of the pushing device 14.

[0073] Therefore, it can be understood that by selecting a negative adjustment angle σ, the movement of the movable block is delayed, while by selecting a positive adjustment angle σ, the movement of the movable block is accelerated. As mentioned above, the adjustment angle can be easily changed by replacing the adjustment wedge 50 with another adjustment wedge and possibly by changing the connecting link 48. However, as mentioned above, the same connecting link 48 can be used with different wedges 50 that can be used in the mold.

[0074] For example, when the ejector plate 16 reaches the ejection position where it contacts the upper wall of the space 18 of the first component 8 (e.g., as... Figure 7When (as shown), the molded article 2 is completely separated from the molding surface 10 and the movable block is completely removed from the undercut area 6. Therefore, the molded article 2 can be removed from the mold without obstruction and without interfering with any part of the mold and ejection device.

[0075] Therefore, the aforementioned ejection device allows for the ejection of large and / or complex-shaped molded articles without weakening the first component of the mold 8. Additionally, a conversion device can be used to adapt the ejection device to the shape of the molded article 2. The drive chain 40 can be easily modified by adding or removing drive links 42, all of which are identical and interchangeable. Furthermore, the angle α between the first axis A1 and the second axis A2 can be changed by simply altering the interface 84 inserted between the first segment 32 and the second segment 36. This interface 84 allows the second segment 36 to be tilted more or less relative to the first segment 32. Therefore, common elements of the ejection device, such as the drive link 42, the actuating rod 31, the first segment 32 and the second segment 36, the actuating element 24, the ejector plate 16, and (one or more) ejector rods 82, can be used in different molds. When the shape of the auxiliary molding surface 12 needs to be changed, only the movable block needs to be changed, and / or when the angle α needs to be changed, only the interface member 84 needs to be changed, and / or when the angle β needs to be changed, only the adjusting wedge member 50 needs to be changed. It should be noted that previously, the angle β was set by modifying the actuator rod 31 so that its interface with the drive chain indicated the desired sliding direction. Therefore, to change the angle β, the actuator rod 31 needs to be changed. According to the invention, the angle β is set by the adjusting wedge member 50, so a single actuator rod 31 can be used regardless of the desired angle. Therefore, the actuator rod 31 can be easily machined to a constant length for different molds.

[0076] The ejection device described above can be modified in various ways while remaining consistent with the present invention. For example, the ejection element 28 may not include an auxiliary molding surface and may only be used to separate the molded article 2 from the molding surface 10, particularly when the main surface 4 of the molded article 2 has a region extending in a direction different from that substantially perpendicular to the opening direction. The drive link 42 may also be formed as a simple block with sliding and guiding surfaces forming its outer surface. In such an embodiment, the links 42 are not directly connected to each other and simply slide in contact with each other.

[0077] Additionally, it is understood that the mold may include multiple ejector elements 28 and corresponding conversion devices 26 to enable the molding and ejection of multiple undercut regions 6 and / or multiple complex-shaped regions of the main surface 4. In this case, a single ejector plate carrying multiple adjusting wedges 50 may be provided to operate all ejector elements 28 simultaneously.

Claims

1. Ejection device for a mold for manufacturing a molded article (2) in a mold cavity, said ejection device being intended to enable the molded article (2) to be ejected from the mold cavity, said device comprising: - a pushing device (14) able to move in translation along a first axis (Al) between a retracted position and an ejection position; - at least one ejection element (28) able to move in translation along a second axis (A2) different from the first axis (Al) between a retracted position and an ejection position, - at least one conversion device (26) connecting the pushing device (14) and the ejection element (28), said conversion device (26) being arranged to make the ejection element (28) move along the second axis (A2) between its retracted position and its ejection position when the pushing device (14) moves along the first axis (Al) between its retracted position and its ejection position, said conversion device (26) comprising a transmission chain (40) comprising at least two transmission links (42) able to move in translation in a sliding direction relative to one another and relative to the pushing device (14) and the ejection element (28), the ejection device being characterized in that it further comprises a plurality of adjustment wedges (50) comprising an adjustment surface (64) forming an adjustment angle (σ) relative to a direction substantially perpendicular to the first axis (Al), wherein at least one adjustment wedge is mounted on the pushing device (14), the transmission chain (40) being mounted on the adjustment surface (64) so that the sliding direction is substantially parallel to the adjustment surface (64), the sliding angle of the transmission links being able to be adjusted by replacing the at least one adjustment wedge by another adjustment wedge having another adjustment angle.

2. The ejection device of claim 1, wherein The adjustment angle (σ) is negative to delay the movement of the ejection element (28) relative to the pushing device (14), positive to accelerate the movement of the ejection element (28) relative to the pushing device (14), or zero to make the ejection element (28) move at the same speed as the pushing device (14).

3. The ejection device according to claim 1 or 2, characterized in that The transmission chain (40) comprises a connecting link (48) mounted able to move in translation on a transmission link (42) on the one hand, the ejection element (28) being mounted able to move in rotation on the connecting link (48) about an axis of rotation substantially perpendicular to the first axis (Al) and to the second axis (A2).

4. The ejection device of claim 3, wherein The connecting link (48) comprises two deflection surfaces (74) of the ejection element (28), each extending from a central portion (76) of the connecting link (48) to an edge of the connecting link (48), the connecting link (48) being oriented relative to the ejection element (28), the deflection surfaces (74) allowing the orientation to vary as a function of the adjustment angle (σ) when the ejection element (28) moves between its retracted position and its ejection position along the second axis (A2).

5. The ejection device of claim 4, wherein The two deflection surfaces (74) of the connecting link (48) are substantially symmetrical relative to the central portion (76) of the connecting link (48).

6. The ejection device of claim 3, wherein The connecting link (48) is connected to the ejection element (28) by a connecting member (56) articulated to the connecting link (48) and to the ejection element (28) so as to allow rotation of the connecting link (48) relative to the ejection element (28).

7. The ejection device according to claim 1 or 2, characterized in that The transmission chain (40) comprises an adjustment link (46) translationally mounted on a transmission link (42), the adjustment link (46) comprising a positioning surface (45) extending on the adjustment surface (64) of the adjustment wedge (50) so that the sliding direction between the adjustment link (46) and the transmission link (42) is substantially parallel to the adjustment surface (64).

8. The ejection device according to claim 1 or 2, characterized in that Each link of the transmission chain (40) comprises at least two sliding surfaces (44) arranged to slide on the sliding surfaces (44) of an adjacent link, the sliding surfaces (44) extending substantially parallel to the adjustment surface (64) of the adjustment wedge (50).

9. The ejection device according to claim 1 or 2, characterized in that Each link of the transmission chain (40) is joined to at least one other link of the transmission chain (40) by at least one connecting member (56) arranged to allow translational displacement of the links relative to each other.

10. The ejection device according to claim 1 or 2, characterized in that The transmission links (42) are identical to each other.

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