A cold-pressing forming device for diamond grinding wheel production

Abstract

The utility model relates to a cold pressure forming device for diamond grinding wheel production, including the lower mould seat of cold pressure forming device, the top of lower mould seat is provided with the inner mould core component, is provided with the outer mould core component and the ejection assembly for grinding wheel demoulding on the inner mould core component. This cold pressure forming device for diamond grinding wheel production, through the gear and rack drive and trapezoidal block slope cooperation, converts horizontal thrust into the vertical jacking force of ejection ring, ejection ring and blank bottom overall contact, replaces push rod single point ejection, avoids the crack and peeling caused by edge stress concentration, and can open two half circle outer mould core when demoulding, avoids the edge damage caused by the friction of half circle outer mould core to embryo vertical direction, and through the synchronous movement of two half circle outer mould core, realizes the opening of two half circle outer mould core in the demoulding process simultaneously, and ensures that ejection ring stress is balanced, avoids the crack caused by the uneven stress of embryo outer edge when ejecting.

Description

Technical Field

[0001] This utility model relates to the field of diamond grinding wheel production technology, specifically a cold pressing forming device for diamond grinding wheel production. Background Technology

[0002] Diamond grinding wheels are superhard abrasives made by using diamond abrasive as the cutting element and fixing it to a matrix with a binder. They are widely used for grinding and polishing hard and brittle materials such as cemented carbide, ceramics, glass, and stone. The production process integrates materials science, machining, and precision control technology. The core process can be divided into six major stages: raw material preparation, mixing, molding, sintering or curing, shaping and finishing, and quality inspection. The production process varies significantly depending on the type of binder. For example, resin binders are cold-pressed, ceramic binders are pressed, and metal binders are hot-pressed.

[0003] In the current technology, the cold pressing process in the diamond grinding wheel production step requires the material to be evenly distributed in the mold, and then the loose material is compacted into a dense blank by the pressure of the hydraulic press. Then the upper mold rises to detach from the surface of the blank, and the lower mold ejection mechanism is activated until the bottom of the blank is higher than the upper edge of the mold cavity. Finally, the blank is gently picked up with soft rubber gloves or tweezers. In actual production, the ejector mechanism uses a push rod to lift the blank, causing it to gradually move upwards. As the upward-moving blank is in close contact with the inner wall of the lower mold, the edges of the blank are subjected to frictional forces with the inner wall of the lower mold. This causes stress concentration at the weak points of the edges, resulting in the gradual scraping and peeling of the material at the edges of the blank, forming serrated notches or peeling layers. The concentration of frictional stress will generate microcracks at the edges of the blank, which is especially obvious in ceramic bonded blanks, causing cracks or breakage at the edges of the blank. Therefore, a cold pressing forming device for diamond grinding wheel production is proposed to solve the above problems. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a cold pressing forming device for diamond grinding wheel production, which has the advantage of protecting the edges of the blank. It solves the problem of using the push rod of the ejection mechanism to lift the blank, causing the blank to gradually move upward. As the upward-moving blank is in close contact with the inner wall of the lower mold, the edge of the blank is subjected to frictional force with the inner wall of the lower mold, resulting in stress concentration at the weak edge. This causes the material at the edge of the blank to be gradually scraped and peeled off, forming serrated notches or peeling layers. The concentration of frictional stress will produce micro-cracks at the edge of the blank, which is more obvious in ceramic bonded blanks, causing cracks or breakage at the edge of the blank.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a cold pressing forming device for diamond grinding wheel production, comprising a lower mold base installed on the cold pressing forming device, an inner mold core assembly provided on the top of the lower mold base, an outer mold core assembly and an ejection assembly for grinding wheel demolding provided on the inner mold core assembly; The inner mold core assembly includes a support platform fixedly installed on the top of the lower mold base, and a cylindrical inner mold core is provided on the support platform; The outer mold core assembly includes two guide plates mounted on a support platform and symmetrically distributed. A semi-circular outer mold core is fixedly mounted on each of the two guide plates, and the two semi-circular outer mold cores and the cylindrical inner mold core form a forming mold core. The ejection assembly includes two connecting blocks that are fixedly connected to two support platforms respectively. Each of the two connecting blocks has a rack fixedly connected to one side of its opposite side. Each of the two connecting blocks has a trapezoidal protrusion. An ejection ring is provided inside the support platform. Two trapezoidal blocks are fixedly installed at the bottom of the ejection ring, and the trapezoidal blocks are in contact with the inclined surfaces of the trapezoidal protrusions. Gears that mesh with the two racks are rotatably installed at the bottom of the support platform. An electric push rod with a telescopic end fixedly connected to one of the connecting blocks is fixedly installed at the bottom of the support platform.

[0006] Furthermore, the top of the support platform is provided with a guide groove, which is slidably connected to two guide plates respectively. The middle of the guide groove is provided with an annular groove that is adapted to the ejector ring, and the bottom of the annular groove is provided with a connecting groove that penetrates the support platform. The connecting groove is slidably connected to the trapezoidal block.

[0007] Furthermore, the guide groove has four limiting grooves that penetrate the support platform, and two limiting blocks are fixedly installed at the bottom of each of the two guide plates, and the limiting blocks are slidably connected to the limiting grooves.

[0008] Furthermore, two bolts are fixedly installed on the guide plate, with one end of the bolt penetrating through the guide plate and the limiting block and extending into the interior of the connecting block. The bolts are threadedly connected to the connecting block.

[0009] Furthermore, the two connecting blocks, rack, trapezoidal protrusion, and trapezoidal block are all symmetrically distributed around the central axis of the gear, and the ejector ring is located at the center of the two semi-circular outer mold cores, with the central axis of the ejector ring coinciding with the central axis of the cylindrical inner mold core.

[0010] Compared with the prior art, the technical solution of this application has the following beneficial effects: 1. This cold pressing forming device for diamond grinding wheel production uses a gear and rack transmission of the ejector assembly to cooperate with the inclined surface of the trapezoidal block. This converts the horizontal thrust of the electric push rod into the vertical lifting force of the ejector ring, and simultaneously drives the outer mold core to slide outward. The ejector ring makes full contact with the bottom of the blank, replacing the single-point ejection of the push rod. This avoids cracks and peeling caused by edge stress concentration. Moreover, during demolding, the two semi-circular outer mold cores can be opened to avoid edge damage caused by the friction of the semi-circular outer mold cores against the blank in the vertical direction. 2. This cold pressing forming device for diamond grinding wheel production uses a connecting block to drive the rack to slide horizontally, which in turn drives the gear to rotate, causing the rack on the other side to move synchronously in the opposite direction. This achieves synchronized movement on both sides, thereby precisely controlling the synchronous movement of the two semi-circular outer mold cores. This allows the two semi-circular outer mold cores to open simultaneously during demolding, and ensures that the ejector ring is subjected to balanced force, avoiding uneven force on the outer edge of the blank during ejection, which could lead to cracks. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the inner mold core assembly and the ejection assembly of this utility model. Figure 3 This is a schematic diagram of the structure of the present utility model. Figure 2 Diagram after flipping over; Figure 4 This is a schematic diagram of the outer mold core assembly and ejection assembly of this utility model. Figure 5 This is a schematic diagram of the ejector component of the structure of this utility model.

[0012] In the diagram: 1. Lower mold base; 2. Inner mold core assembly; 21. Support platform; 22. Guide groove; 23. Cylindrical inner mold core; 24. Limiting groove; 3. Outer mold core assembly; 31. Guide plate; 32. Semi-circular outer mold core; 33. Limiting block; 4. Ejector assembly; 41. Connecting block; 42. Rack; 43. Trapezoidal protrusion; 44. Ejector ring; 45. Trapezoidal block; 46. Gear; 47. Electric push rod. Detailed Implementation

[0013] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0014] Example 1: Please refer to Figure 1-5This embodiment provides a cold pressing forming device for diamond grinding wheel production, including a lower mold base 1 installed on the cold pressing forming device, an inner mold core assembly 2 provided on the top of the lower mold base 1, an outer mold core assembly 3 and an ejection assembly 4 for grinding wheel demolding provided on the inner mold core assembly 2.

[0015] Example 2: Please refer to Figure 1-5 Based on Embodiment 1, the inner mold core assembly 2 includes a support platform 21 fixedly installed on the top of the lower mold base 1, and a columnar inner mold core 23 is provided on the support platform 21. The outer mold core assembly 3 includes two guide plates 31 that are symmetrically distributed and mounted on the support platform 21. A semi-circular outer mold core 32 is fixedly mounted on each of the two guide plates 31, and the two semi-circular outer mold cores 32 and the cylindrical inner mold core 23 form a molding mold core. The ejector assembly 4 includes two connecting blocks 41 that are fixedly connected to two support platforms 21 respectively. Each of the two connecting blocks 41 has a rack 42 fixedly connected to one side of its opposite side. Each of the two connecting blocks 41 has a trapezoidal protrusion 43. An ejector ring 44 is provided inside the support platform 21. Two trapezoidal blocks 45 are fixedly installed at the bottom of the ejector ring 44, and the trapezoidal blocks 45 are in contact with the inclined surfaces of the trapezoidal protrusions 43. Gears 46 that mesh with the two racks 42 are rotatably installed at the bottom of the support platform 21. An electric push rod 47 with its telescopic end fixedly connected to one of the connecting blocks 41 is fixedly installed at the bottom of the support platform 21.

[0016] The top of the support platform 21 is provided with a guide groove 22, which is slidably connected to two guide plates 31. The middle of the guide groove 22 is provided with an annular groove that matches the ejector ring 44, and the bottom of the annular groove is provided with a connecting groove that passes through the support platform 21. The connecting groove is slidably connected to the trapezoidal block 45. The guide groove 22 constrains the movement trajectory of the guide plate 31, ensuring that the semi-circular outer mold core 32 is separated in a straight line, avoiding lateral displacement that aggravates the friction of the blank. The annular groove matches the ejector ring 44, limiting its radial sway and ensuring the vertical accuracy of the lifting process.

[0017] In addition, four limiting grooves 24 penetrating the support platform 21 are provided inside the guide groove 22. Two limiting blocks 33 are fixedly installed at the bottom of the two guide plates 31, and the limiting blocks 33 are slidably connected to the limiting grooves 24. The cooperation between the limiting grooves 24 and the limiting blocks 33 restricts the movement range of the guide plates 31, preventing excessive separation of the semi-circular outer mold core 32 and causing the blank support to fail. The four-point limiting enhances the torsional rigidity of the guide plates 31 and avoids movement deviation caused by uneven force. The clearance fit between the limiting blocks 33 and the limiting grooves 24 can compensate for mold manufacturing errors.

[0018] It should be noted that two bolts are fixedly installed on the guide plate 31, and one end of the bolt passes through the guide plate 31 and the limiting block 33 and extends into the interior of the connecting block 41. The bolt is threadedly connected to the connecting block 41, and the bolt rigidly connects the guide plate 31 and the connecting block 41 to ensure that it does not loosen during high-frequency ejection and maintains the synchronization of movement. The bolt preload can optimize the contact stiffness between the guide plate 31 and the support platform 21 and reduce wear caused by vibration.

[0019] With the above technical solution, the ejector ring 44 makes full contact with the bottom of the blank, replacing the single-point ejection of the push rod, avoiding cracks and peeling caused by edge stress concentration. The semi-circular outer mold core 32 slides outward to release the constraint on the edge of the blank, significantly reducing the friction during demolding. It is especially suitable for brittle ceramic bonded blanks. The high-precision synchronization of the gear 46 and rack 42 transmission can improve the consistency of blank size and reduce eccentric defects caused by asynchronous ejection.

[0020] Example 3: Please refer to Figure 1-5 Based on Embodiment 2, the two connecting blocks 41, rack 42, trapezoidal protrusion 43 and trapezoidal block 45 are all symmetrically distributed around the central axis of gear 46, and the ejector ring 44 is located at the center of the two semi-circular outer mold cores 32, with the central axis of the ejector ring 44 coinciding with the central axis of the cylindrical inner mold core 23.

[0021] Using the above technical solution, the key components of the ejection assembly 4 are symmetrically distributed along the central axis of the gear 46. The ejection ring 44 is coaxial with the cylindrical inner mold core 23. The symmetrically distributed rack 42 and trapezoidal block 45 ensure that the ejection ring 44 is subjected to balanced force, avoiding bending cracks in the blank due to eccentric loading. The coaxial design of the ejection ring 44 and the cylindrical inner mold core 23 keeps the blank centrally symmetrical during the lifting process, preventing the local friction at the edges from intensifying.

[0022] The working principle of the above embodiments is as follows: This cold pressing forming device for diamond grinding wheel production, when in use, after the upper mold rises and separates from the blank, the electric push rod 47 is started, pushing the connecting block 41 to move away from the gear 46. The connecting block 41 drives the rack 42 to slide horizontally, driving the gear 46 to rotate, so that the rack 42 on the other side moves synchronously in the opposite direction, realizing the synchronous movement of both sides. The trapezoidal protrusion 43 of the rack 42 pushes the trapezoidal block 45, and the ejector ring 44 rises vertically along the annular groove, lifting the blank from the cylindrical inner mold core 23. The guide plate 31 moves horizontally with the connecting block 41, and the semi-circular outer mold core 32 slides outward along the guide groove 22, releasing the squeezing constraint on the edge of the blank. Under the action of the ejector ring 44, the blank completely leaves the cavity. After the blank is lifted to the upper edge of the mold cavity, it can be removed directly by manual or mechanical means, which can effectively avoid edge friction damage during ejection.

[0023] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0024] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A cold pressing forming apparatus for diamond grinding wheel production, comprising a lower die holder (1) mounted on the cold pressing forming apparatus, characterized in that: The lower mold base (1) is provided with an inner mold core assembly (2) on its top, and an outer mold core assembly (3) and an ejection assembly (4) for grinding wheel demolding are provided on the inner mold core assembly (2). The inner mold core assembly (2) includes a support platform (21) fixedly installed on the top of the lower mold base (1), and a cylindrical inner mold core (23) is provided on the support platform (21). The outer mold core assembly (3) includes two guide plates (31) installed on the support platform (21) and symmetrically distributed. A semi-circular outer mold core (32) is fixedly installed on each of the two guide plates (31), and the two semi-circular outer mold cores (32) and the cylindrical inner mold core (23) form a molding mold core. The ejection assembly (4) includes two connecting blocks (41) that are fixedly connected to two support platforms (21) respectively. A rack (42) is fixedly connected to one side of each of the two connecting blocks (41). A trapezoidal protrusion (43) is provided on each of the two connecting blocks (41). An ejection ring (44) is provided inside the support platform (21). Two trapezoidal blocks (45) are fixedly installed at the bottom of the ejection ring (44), and the trapezoidal blocks (45) are in contact with the inclined surface of the trapezoidal protrusion (43). A gear (46) that meshes with the two racks (42) is rotatably installed at the bottom of the support platform (21). An electric push rod (47) with its telescopic end fixedly connected to one of the connecting blocks (41) is fixedly installed at the bottom of the support platform (21).

2. The cold pressing forming apparatus for diamond grinding wheel production according to claim 1, characterized in that: The top of the support platform (21) is provided with a guide groove (22), and the guide groove (22) is slidably connected to two guide plates (31). The middle part of the guide groove (22) is provided with an annular groove that is adapted to the ejection ring (44), and the bottom of the annular groove is provided with a connecting groove that penetrates the support platform (21). The connecting groove is slidably connected to the trapezoidal block (45).

3. The cold pressing forming apparatus for diamond grinding wheel production according to claim 2, characterized in that: The guide groove (22) has four limiting grooves (24) that pass through the support platform (21). Two limiting blocks (33) are fixedly installed at the bottom of the two guide plates (31), and the limiting blocks (33) are slidably connected to the limiting grooves (24).

4. The cold pressing forming apparatus for diamond grinding wheel production according to claim 1, characterized in that: Two bolts are fixedly installed on the guide plate (31), and one end of the bolt passes through the guide plate (31) and the limiting block (33) and extends into the interior of the connecting block (41). The bolt is threadedly connected to the connecting block (41).

5. A cold pressing forming apparatus for diamond grinding wheel production according to claim 1, characterized in that: The two connecting blocks (41), rack (42), trapezoidal protrusion (43) and trapezoidal block (45) are all symmetrically distributed around the central axis of the gear (46), and the ejector ring (44) is located at the center of the two semi-circular outer mold cores (32), with the central axis of the ejector ring (44) coinciding with the central axis of the cylindrical inner mold core (23).

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