Novel pressing mechanism

Abstract

The novel pressing mechanism comprises a base, a movable mold plate, a fixed mold plate, a mold moving device, a mold locking device and a pull rod, and the movable mold plate is driven by the mold moving device to move along the pull rod installed on the fixed mold plate; the mold locking device comprises a mold locking power source, a mold locking wedge and a wedge block; when the movable mold plate and the fixed mold plate are closed, the mold locking power source drives the mold locking wedge to move in the direction perpendicular to the moving direction of the movable mold plate, and the mold locking wedge is gradually wedged with the wedge block, so that the movable mold plate is gradually pressed to be locked on the back side of the movable mold plate. The mold locking device perpendicular to the moving direction of the movable mold plate is arranged and pushes a wedge between the movable mold plate and the mold locking frame, thrust generated by the mold locking wedge presses the movable mold plate to the fixed mold plate, it is guaranteed that when a product is formed in the mold, the movable mold plate does not retreat, and the reverse thrust of the movable mold plate is borne by fixing structures such as the mold locking frame and a pull rod; the pull rod can bear the mold locking force and also has the effects of guiding and bearing the weight of the movable mold plate, so that the structural design is simplified, and the cost is saved.

Description

Technical Field

[0001] The invention belongs to the technical field of injection molding machines, die-casting machines and molding machines, and in particular, relates to a novel pressing mechanism. Background Art

[0002] The traditional mold clamping system contains a rear plate, a movable platen and a fixed platen, and is usually called a three-platen die-casting machine. The mold opening and closing actions are completed by the bending and extension of the elbow, and the mold is locked in the straight state. The mold opening and closing actions are completed by the mold clamping cylinder, and the locking is completed by the elbow. Therefore, it is hydraulic mold opening and closing and mechanical locking.

[0003] At present, there are improved technologies for special mold locking for mold clamping mechanisms on the market, most of which are mainly based on screw locking. For example, Chinese patent CN207290826U discloses an electro-hydraulic hybrid mold locking device, which is equipped with a hydraulic drive device, and the gaps of the two locking parts form a locking hole. The guide rod is accommodated in the locking hole, so that the locking part can firmly lock the guide rod to achieve the purpose of mold locking. However, its locking structure is to tighten the guide rod by thread. Due to the reaction force of the guide rod, its stability is poor, and it is very easy for the dynamic platen to give way.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a new pressing mechanism. To solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0006] A novel pressing mechanism comprises a base, a movable platen, a fixed platen, a mold shifting device, a mold locking device, and a pull rod. The fixed platen is fixedly mounted on the base, and the movable platen is driven by the mold shifting device to move along the pull rod mounted on the fixed platen.

[0007] The mold locking device includes a mold locking power source, a mold locking wedge, and a wedge block; when the movable mold plate and the fixed mold plate are molded together, the mold locking power source drives the mold locking wedge to move in a direction perpendicular to the movement direction of the movable mold plate, and gradually wedges the mold locking wedge with the wedge block to gradually press the movable mold plate on the back side of the movable mold plate until it is locked.

[0008] Furthermore, the wedge angle between the locking wedge and the wedge block is 0° to 30°.

[0009] Furthermore, the clamping devices are composed of several groups, which are evenly distributed along the circumference of the back side end of the movable mold plate.

[0010] Furthermore, the clamping wedge is installed on the movable platen through a clamping power source, and the wedge block is installed on the pull rod.

[0011] Furthermore, the clamping wedge is installed on the pull rod through the clamping power source, and the wedge block is installed on the movable platen.

[0012] Furthermore, there are four tie rods distributed along the circumference of the moving template, and the four tie rods are connected and fixed on the base by tie rod support columns and tie rod connecting frames.

[0013] Furthermore, a clamping frame is provided on the fixed sleeve on the pull rod, and a clamping wedge or a wedge block is installed on the clamping frame.

[0014] Furthermore, the clamping power source is a clamping cylinder or a clamping motor.

[0015] Furthermore, the locking power source is a locking motor, which is driven and connected to the locking screw. A connecting card is screwed on the locking screw. Both ends of the locking connecting rod are respectively hinged to the locking wedge and the connecting card. The locking motor drives the locking screw to move the connecting card along the axial direction of the screw.

[0016] Furthermore, the mold locking power source is a mold locking motor, and the mold locking motor drives the mold locking wedge to move via a lead screw.

[0017] After adopting the above technical scheme, the present invention has the following beneficial effects compared with the prior art.

[0018] The present invention provides a locking device which is perpendicular to the movement direction of the movable platen. The locking device pushes the inclined wedge between the movable platen and the locking frame. The thrust generated by the locking wedge presses the movable platen toward the fixed platen, ensuring that the movable platen will not retreat when the product is formed in the mold. The reverse thrust of the movable platen is borne by the locking frame, the pull rod and other fixed structures. In addition to bearing the locking force, the pull rod also plays a role in guiding and bearing the weight of the movable platen, thereby simplifying the structural design and saving equipment costs.

[0019] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are part of this application and are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the drawings described below are only some embodiments. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1 It is a structural schematic diagram of embodiment 1 of the present invention;

[0022] Figure 2 is a cross-sectional view of the unlocked state of embodiment 1 of the present invention;

[0023] Figure 3 This is a cross-sectional view of the clamping state of Embodiment 1 of the present invention;

[0024] Figure 4 Schematic diagram of another arrangement scheme of the clamping device of embodiment 1 of the present invention;

[0025] Figure 5 It is a structural schematic diagram of embodiment 2 of the present invention;

[0026] Figure 6 This is a cross-sectional view of the clamping state of Embodiment 2 of the present invention;

[0027] Figure 7 Schematic diagram of force analysis of the clamping wedge in Embodiment 2 of the present invention;

[0028] Figure 8 Schematic diagram of the screw-driven clamping wedge in Embodiment 3 of the present invention;

[0029] Fig. 9 Schematic diagram of the mold locking state of the mold locking connecting rod in Embodiment 3 of the present invention;

[0030] Fig.10 Schematic diagram of the unlocking state of the mold locking connecting rod in Embodiment 3 of the present invention;

[0031] Fig.11 Schematic diagram of force analysis of the clamping connecting rod in Embodiment 3 of the present invention;

[0032] Fig.12 is a schematic structural diagram of Embodiment 4 of the present invention;

[0033] Fig.13 This is a schematic diagram of the mold locking state in Example 4 of the present invention;

[0034] Fig.14 This is a schematic diagram of the unlocking state in Example 4 of the present invention.

[0035] In the figure:

[0036] 1-base; 2-moving template; 3-fixed template;

[0037] 401- clamping cylinder; 402- clamping wedge; 403- wedge block; 404- clamping motor; 405- clamping screw; 406- clamping connecting rod;

[0038] 5- clamping frame; 601- tie rod; 602- tie rod support column; 603- tie rod connecting frame;

[0039] 7-mold transfer cylinder; 8-injection unit; 9-mold; 10-ejection device;

[0040] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0042] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0043] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] like Figures 1 to 14 As shown, a novel pressing mechanism described in the present invention comprises a base 1, a movable die plate 2, a fixed die plate 3, a die shifting device, a die locking device, and a tie rod 601. The fixed die plate 3 is fixedly mounted on the base 1, and the movable die plate 2 is driven by the die shifting device to move along the tie rod 601 mounted on the fixed die plate 3, that is, the tie rod 601 is a guide rail or guide rod of the movable die plate 2, and the movable die plate 2 and the fixed die plate 3 are molded together. The die locking device locks the movable and fixed die plates to ensure the closed state of the mold during forming.

[0045] The locking device includes a locking power source, a locking wedge 402, and a wedge block 403. When the movable plate 2 and the fixed plate 3 are molded, the locking power source drives the locking wedge 402 to move in a direction perpendicular to the moving direction of the movable plate 2, and gradually wedges the locking wedge 402 with the wedge block 403, so as to gradually press the movable plate 2 to lock on the back side of the movable plate 2. The movable plate 2 moves along the guide rod 601, and its moving direction is the moving direction of the movable plate 2. If it is represented by the X-axis, the moving direction of the locking wedge 402 can be represented by the Y-axis, and then the X-axis and the Y-axis are perpendicular. The locking wedge 402 and the wedge block 403 are two components with wedge surfaces. The wedge surfaces of the two fit each other and will gradually wedge. Here, one of the locking wedge 402 and the wedge block 403 must be installed on the movable plate 2, and the other is fixed in position, which can be fixedly installed on a pull rod, a base or other fixed structure. After the two are wedged tightly, a stop structure will be formed on the back side of the movable platen 2 to prevent the movable platen 2 from retreating, thereby ensuring that the mold is in a stable mold clamping state. The back side here is relatively speaking, the positive side is the side where the movable platen and the fixed platen are clamped, and the opposite side is the back side. Figure 2 It is shown that in this figure, the back side is the left side of the moving plate 2.

[0046] The clamping device is arranged on the back side of the movable template 2 and can form a resistance to the movable template 2. Therefore, the number of clamping devices is preferably arranged in a symmetrical manner, that is, 2N devices are used, and then evenly distributed along the circumference of the back end of the movable template 2, such as on the upper and lower sides, or the left and right sides, or on all sides. Multiple devices can also be set on one side. The purpose is to prevent the movable template 2 from retreating. The number of clamping devices can be selected according to the force applied to the movable template 2, the volume size, etc.

[0047] Different methods can be selected for the installation positions of the clamping wedge 402 and the wedge block 403, such as the clamping wedge 402 is installed on the movable platen 2, connected with it in a sliding manner, and can be moved by the clamping power source, and the wedge block 403 is installed on the tie rod 601. Alternatively, the clamping wedge 402 is installed on the tie rod 601, and the wedge block 403 is installed on the movable platen 2. Alternatively, a clamping frame 5 is fixedly sleeved on the tie rod 601, and one of the clamping wedge 402 or the wedge block 403 is installed on the clamping frame 5, and the other is installed on the movable platen 2. The number of tie rods 601 can also be arranged according to the approximate shape of the movable platen, such as the movable platen 2 is in a cubic shape, and there are four tie rods 601, which are evenly distributed along the circumference of the movable platen 2, and the four tie rods 601 are connected and fixed on the base 1 by tie rod support columns 603 and tie rod connecting frames 602.

[0048] The above-mentioned mold locking power source is a driving source, and the mold locking oil cylinder 401 or the mold locking motor 404 can be selected. As long as it can drive the mold locking wedge 402 to move, the demand can be met. Of course, according to different travel modes, the piston can directly move the mold locking wedge 402, the screw can move the mold locking wedge 402, or the connecting rod can move the mold locking wedge 402. The structural form is varied and can be selected according to the demand.

[0049] When the locking wedge 402 and the wedge block 403 are wedged tightly, the movable plate 2 is stopped to prevent the movable plate 2 from retreating. The inclined angle of the locking wedge 402 and the wedge block 403 has an impact on the force. Figure 7 As shown, the clamping force calculation formula is:

[0050]

[0051] Among them: F t is the thrust of the clamping cylinder, F a is the locking force generated by a single clamping wedge, n is the number of clamping devices, is the friction angle between the inclined wedge and the fixed template, is the friction angle between the inclined surfaces of the wedge, θ is the wedge angle of the clamping wedge, and the smaller θ is, the greater the force-enhancing effect of the clamping cylinder is.

[0052] It can be seen from the above formula that the size of the clamping force can be freely set by changing the pressure of the clamping cylinder, the number of locking rods, and the wedge angle of the wedge block to adapt to different molding processes. The thrust of the clamping is provided by the driving source, which can be provided by the cylinder or by the motor through the screw rod. The thrust is changed by changing the motor torque, and then the clamping force is adjusted. In practical applications, the number of clamping devices generally remains unchanged, and the clamping force is adjusted by adjusting the wedge angle. Generally, the adjustment range of the wedge angle is 0° to 30°. The smaller the angle, the greater the accuracy of the clamping force fine-tuning during the locking process. For molds of different thicknesses, the mold closing position needs to be adjusted. There are two methods: one is to adjust the thickness of the clamping wedge 402 or the wedge block 403, and the other is to change the locking position.

[0053] Example 1

[0054] like Figure 1-4 As shown, a novel pressing mechanism described in this embodiment includes a base 1, a movable platen 2, a fixed platen 3, a clamping frame 5, a mold shifting device, a clamping device, a tie rod 601, an injection unit 8, and an ejection device 10. The base 1 is used as a base, and the fixed platen 3 is fixedly mounted on the base 1. There are four tie rods 601, which are connected into a frame through tie rod support columns 602 and tie rod connecting frames 603 to maintain the stability of the tie rods 601.

[0055] The movable platen 2 moves along the tie rod 601, which plays a guiding and supporting role. The clamping frame 5 is fixed to the tie rod 601 and is vertical, perpendicular to the horizontal state of the tie rod 601. When the movable platen 2 moves along the tie rod 601, the clamping frame 5 will not affect it. In this example, the mold shifting device is the mold shifting cylinder 7, which drives the movable platen 2 to move through a screw (not shown in the figure). The injection unit 8 is installed on one side of the fixed platen 3, and the ejection device 10 is installed on one side of the movable platen 2. The injection unit 8 and the ejection device 10 are conventional structures and will not be repeated here.

[0056] There are two sets of mold locking devices in this example, which are arranged on the upper and lower end surfaces of the movable platen 2 respectively. The mold locking devices include a mold locking cylinder 401 (not shown in the figure), a mold locking wedge 402, and a wedge block 403. The mold locking cylinder 401 is installed on the movable platen 2. When the mold locking wedge 402 is not matched with the wedge block 403, it is located in the notch opened in the movable platen 2 (the notch serves as its hiding place). Figure 2-3 The extending and retracting states of the mold locking wedge 402 can be seen in FIG. When mold locking is required, the mold locking cylinder 401 drives the mold locking wedge 402 to extend to cooperate with the wedge block 403 to wedge tightly, thereby stopping the movable mold plate 2 and achieving the purpose of mold locking.

[0057] In addition, the clamping device can also be arranged on the left and right side end surfaces of the movable plate 2, as shown in the attached Figure 4 As shown, four groups of structures are adopted, two on the left and two on the right, and the only difference is the position of the clamping device. Of course, a solution of distributing the clamping devices around can also be adopted.

[0058] Advantages of using this embodiment:

[0059] 1. The tie rod is fixed and does not move with the moving platen, thus reducing the weight of moving parts and increasing the speed of mold opening and closing;

[0060] 2. The tie rod plays the role of both guiding and bearing. Compared with machining the guide rail on a larger base, the machining difficulty of the tie rod guide surface is greatly reduced;

[0061] 3. By changing the thickness of the wedge installed on the moving platen, or adjusting the installation position of the clamping frame on the tie rod, it can be easily adjusted to different mold thicknesses.

[0062] Example 2

[0063] like Figure 5-6 As shown, the new type of pressing mechanism described in this embodiment is different from the above-mentioned embodiment 1 in that: in this embodiment, the clamping cylinder 401 is installed on the clamping frame 5, and the wedge block 403 is installed on the movable platen 2, see the attached Figure 5-6As shown, the movable platen 2 is provided with a slot for installing the wedge block 603, and the clamping frame 5 is provided with mounting holes for installing the clamping cylinder 601 and the clamping wedge 602. The clamping cylinder 601 moves telescopically with the clamping wedge 602 in the mounting hole.

[0064] Example 3

[0065] like Figure 8-11 As shown, the new type of pressing mechanism described in this embodiment is different from the above-mentioned embodiment 1 in that there is no clamping frame 5 structure, and the pull rod 601 is provided with a protrusion for installing the wedge block 403, that is, the wedge block 403 is installed on the pull rod 601, and the clamping wedge 402 is installed on the moving plate 2. The clamping power source in this embodiment is the clamping motor 404, as shown in the attached Figure 8 As shown in the figure, wedge blocks 403 are provided on each of the four tie rods, and only the structure of the two upper tie rods is shown in the figure. A locking motor 404 is arranged between the two upper tie rods 601, and the locking motor 404 drives a screw on each side, and the other end of the screw is a locking wedge 402. The threads of the left and right locking wedges 402 are in opposite directions. The locking wedge 402 is slidably connected to the movable mold plate 2 and cannot rotate. With such an arrangement, after the locking motor 404 is started, the synchronous telescopic movement of the left and right locking wedges 402 can be achieved at the same time.

[0066] The wedge block 403 is directly arranged on the tie rod 601, which can reduce the structure of the clamping frame 5. Of course, several tie rod connecting frames 603 can be added between the four tie rods 601 to enhance its stability. In addition, the drive of the clamping wedge 402 can be further optimized, as shown in the attached figure. Figure 9-11 Hint:

[0067] The mold locking motor 404 is connected to the mold locking screw 405. A connecting clip is screwed on the mold locking screw 405. The two ends of the mold locking connecting rod 406 are respectively hinged to the mold locking wedge 402 and the connecting clip. When the motor is working, the mold locking screw 405 rotates. Due to the position limit of the connecting clip by the left and right mold locking connecting rods 406, the connecting clip can only move along the axial direction of the screw. In this way, the connecting rod drives the mold locking wedge 402. The use of the connecting rod can amplify the propulsion force. Fig.11 As shown, the thrust F is magnified t The calculation formula is:

[0068]

[0069] Among them: F m is the thrust generated by the motor, and α is the angle between the connecting rod and the moving direction of the wedge.

[0070] After the wedge surface force is amplified, the total clamping thrust is:

[0071]

[0072] With this structural setting, under the same clamping force requirement, a smaller power motor can be used to further reduce the equipment cost. Conversely, the size span of the clamping force can be increased without changing the equipment.

[0073] Example 4

[0074] like Figure 12-14 As shown, the novel pressing mechanism described in this embodiment is different from the above-mentioned embodiment 3 in that a clamping motor 404 is arranged between the two tie rods 601, that is, one clamping motor 404 is arranged above and below, and the clamping wedge 402 is in the shape of a long strip and spans over the two tie rods 601. Fig.12 As shown in the figure, the length of the mold locking wedge 402 exceeds the width of the two tie rods 601. When the mold locking wedge 402 is in the unlocked state, it is located above or below the tie rod 601, that is, the mold locking wedge 402 is located outside the tie rod 601. When the mold locking wedge 402 is locked, the mold locking motor 404 moves the mold locking wedge 402 (either a screw or a lead screw), so that the mold locking wedge 402 gradually approaches the tie rod 601, and the mold locking wedge 402 and the wedge block 403 on the tie rod 601 are gradually wedged to achieve mold locking.

[0075] This embodiment can reduce the number of locking wedges. Compared with one locking wedge corresponding to each pull rod, the same locking wedge in this example is wedged by the wedges of two pull rods, which improves the overall stability of the wedging and further improves the reliability of the locking.

[0076] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A novel pressing mechanism, comprising a base (1), a movable die plate (2), a fixed die plate (3), a die shifting device, a die locking device, and a tie rod (601), wherein the fixed die plate (3) is fixedly mounted on the base (1), and the movable die plate (2) is driven by the die shifting device to move along the tie rod (601) mounted on the fixed die plate (3), characterized in that: The mold locking device comprises a mold locking power source, a mold locking wedge (402), and a wedge block (403). When the movable mold plate (2) and the fixed mold plate (3) are molded together, the mold locking power source drives the mold locking wedge (402) to move in a direction perpendicular to the moving direction of the movable mold plate (2), and gradually wedges the mold locking wedge (402) with the wedge block (403) to gradually press the movable mold plate (2) on the back side of the movable mold plate (2) until it is locked.

2. According to the claim 1 The novel pressing mechanism is characterized in that: The wedge angle between the locking wedge (402) and the wedge block (403) is 0° to 30°.

3. A new type of pressing mechanism according to claim 1, characterized in that: The mold locking devices are composed of a plurality of groups, which are evenly distributed along the circumference of the back side end of the movable mold plate (2).

4. A new type of pressing mechanism according to claim 1, characterized in that: The clamping wedge (402) is installed on the movable platen (2) through a clamping power source, and the wedge block (403) is installed on the pull rod (601).

5. A new type of pressing mechanism according to claim 1, characterized in that: The clamping wedge (402) is installed on the pull rod (601) through the clamping power source, and the wedge block (403) is installed on the movable platen (2).

6. A new type of pressing mechanism according to claim 1, characterized in that: There are four tie rods (601) distributed along the circumference of the movable template (2). The four tie rods (601) are connected and fixed on the fixed template (3) by tie rod support columns (603) and tie rod connecting frames (602).

7. A new type of pressing mechanism according to claim 1, characterized in that: A mold locking frame (5) is fixedly sleeved on the pull rod (601), and a mold locking wedge (402) or a wedge block (403) is installed on the mold locking frame (5).

8. A novel pressing mechanism according to claim 1, characterized in that: The mold locking power source is a mold locking cylinder (401) or a mold locking motor (404).

9. A new type of pressing mechanism according to claim 1, characterized in that: The mold locking power source is a mold locking motor (404), which is connected to the mold locking screw (405) by driving. A connecting card is screwed on the mold locking screw (405), and two ends of the mold locking connecting rod (406) are respectively hinged to the mold locking wedge (402) and the connecting card. The mold locking motor (404) drives the mold locking screw (405) to move the connecting card along the axial direction of the screw.

10. A new type of pressing mechanism according to claim 1, characterized in that: The mold locking power source is a mold locking motor (404), and the mold locking motor (404) drives the mold locking wedge (402) to move via a lead screw.

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