Precision casting sand mould vibration demoulding machine

Abstract

The application provides a precision casting sand mold vibration demolding machine, and mainly relates to the field of precision casting vibration demolding. The precision casting sand mold vibration demolding machine is characterized by that a demolding mechanism is arranged on the opposite side of a positioning mechanism; the positioning mechanism comprises a horizontal moving slide rail and a horizontal moving seat perpendicular to the horizontal plane; a horizontal moving force mechanism is arranged on one side of the horizontal moving slide rail to drive the horizontal moving seat to reciprocally slide; a vibration frame is arranged on the front side of the horizontal moving seat; a buffer mechanism is arranged between the vibration frame and the horizontal moving seat; a positioning seat is rotatably arranged in the middle of the vibration frame; a plurality of positioning clamps are arranged on the positioning seat; an adjusting motor is arranged on the rear side of the horizontal moving seat; the demolding mechanism comprises an extension rail perpendicular to the horizontal moving seat and an extension cylinder; a mounting seat is slidably arranged on the extension rail; and at least one air hammer is arranged on the mounting seat. The application has the beneficial effect that the application can change the action point of vibration demolding, is more convenient for the crushing and falling of the sand mold, and improves the demolding effect of the precision casting.

Description

Technical Field

[0001] This invention mainly relates to the field of vibration demolding of precision castings, specifically a vibration demolding machine for sand molds of precision castings. Background Technology

[0002] Precision casting is a high-precision and high-efficiency casting process, widely used in the machinery manufacturing industry to manufacture high-strength, high-precision, irregularly shaped workpieces. Precision casting involves applying casting sand to a wax pattern to form a sand mold, which is then sintered to serve as the sand mold. Molten metal is then poured into the mold, and after cooling, the workpiece is formed. Once the casting is complete, the surface of the workpiece is subjected to high-frequency vibration by vibrating machinery, breaking the sand mold and detaching it from the surface of the workpiece.

[0003] Currently, conventional sand mold vibration demolding devices mostly use vibration to act on a fixed point or plane of the workpiece. For workpieces with complex shapes, this vibration demolding method is ineffective in certain areas, especially in areas with holes where broken sand shells accumulate, significantly interfering with subsequent crushing and affecting the removal of the sand mold. Therefore, when demolding such complex and large workpieces, operators often need to manually peel off the sand or manually adjust its position for secondary or tertiary vibration demolding. There is a device that uses a rotating unit to fix the sand mold, and the sand shell falls off by rotating the angle, facilitating subsequent sand shell removal. However, the vibration mechanism (air hammer) of this device rotates with the casting, and its vibration point does not change, which means that the sand mold removal effect still has flaws. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a precision casting sand mold vibration demolding machine, which can change the point of action of vibration demolding, making it easier for the sand mold to break and fall off, and improving the demolding effect of precision castings.

[0005] To achieve the above objectives, the present invention employs the following technical solution:

[0006] A precision casting sand mold vibration demolding machine includes a frame with a demolding space. A positioning mechanism is provided on one side of the demolding space, and a demolding mechanism is provided on the opposite side of the positioning mechanism. The positioning mechanism includes a transverse slide rail and a transverse seat perpendicular to the horizontal plane. The transverse seat is slidably connected to the transverse slide rail. A transverse force mechanism for driving the transverse seat to slide back and forth is provided on one side of the transverse slide rail. A vibration frame is provided in front of the transverse seat, and a buffer mechanism is provided between the vibration frame and the transverse seat. A positioning seat is rotatably provided in the middle of the vibration frame, and a plurality of positioning clamps are provided on the positioning seat. An adjustment motor is provided behind the transverse seat to drive the positioning seat to rotate. The demolding mechanism includes an extension rail arranged perpendicular to the transverse seat and an extension cylinder. A mounting seat is slidably provided on the extension rail, and at least one air hammer is provided on the mounting seat. When the mounting seat extends, the air hammer adapts to the sand casting fixed on the positioning seat.

[0007] Preferably, the buffer mechanism includes a hinge member disposed on one side of the transverse seat and the vibration frame, a plurality of damping washers are disposed between the transverse seat and the vibration frame, and a clamping cylinder is disposed on the side of the transverse seat where the hinge member is not installed. When the clamping cylinder extends, it abuts against the vibration frame, making the vibration frame parallel to the transverse seat.

[0008] Preferably, the motor shaft of the adjusting motor is connected to the positioning seat via a transmission flexible shaft.

[0009] Preferably, two air hammers are provided, and the two air hammers vibrate alternately to achieve demolding of the sand casting.

[0010] Preferably, the mounting base is provided with an adjustment rail, and an adjustment mechanism is provided on the rear side of the adjustment rail. The air hammer is slidably connected to the adjustment rail, and the adjustment mechanism is used to drive the air hammer to slide along the adjustment rail.

[0011] Preferably, a hinged flap is mounted on the frame, the bottom of the flap is hinged to the frame, the positioning mechanism is mounted on the flap, and a tilting cylinder is provided between the rear side of the flap and the frame. When the tilting cylinder retracts, the flap is in a horizontal state, and when the tilting cylinder extends, the flap is in a vertical state.

[0012] Preferably, a locking pin is provided on the side of the flip plate that contacts the frame, and a mating pin that cooperates with the locking pin is provided on the side of the frame that contacts the flip plate. A locking cylinder is provided on one side of the mating pin, and a locking device that slides with the mating pin is provided on the piston shaft of the locking cylinder. The locking device is restricted to the outside of the locking pin and the mating pin after being pushed by the locking cylinder.

[0013] Preferably, the frame on the rear side of the flap has a support frame. When the flap is retracted, the rear side of the flap abuts against the support frame, so that the flap is in a horizontal state.

[0014] Preferably, the frame is covered by a sealed box, and the front of the sealed box has an opening and closing door.

[0015] Preferably, the sealed housing has a negative pressure dust removal pipeline for collecting dust under negative pressure.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] This invention has a simple structure and high efficiency, and can stably realize the vibration demolding of precision casting sand molds, greatly improving the demolding effect and demolding efficiency of sand molds.

[0018] This invention employs a transverse and rotational structure, which can drive the precision casting to perform stable position switching, thereby changing the vibration position of the vibration mechanism. This allows for changes in the vibration intensity of different areas of the casting, enabling targeted vibration demolding of stubborn demolding locations and achieving a better demolding effect.

[0019] The air hammer of this invention does not adjust its position with the adjustment of the casting, thus it can make targeted changes to the vibration position, realize the point-to-point crushing and demolding of different areas on the surface of the precision casting, and improve the demolding effect of the precision casting.

[0020] The invention also adds a flipping structure, which improves the convenience of loading and unloading workpieces while enabling horizontal operation, reduces the difficulty of vertically fixing the demolding fasteners, and improves overall safety. Attached Figure Description

[0021] Appendix Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0022] Appendix Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0023] Appendix Figure 3 This is the present invention. Figure 2 Schematic diagram of the AA section structure;

[0024] Appendix Figure 4 This is a schematic diagram of the structure of Embodiment 3 of the present invention;

[0025] Appendix Figure 5 This is a schematic diagram of the structure of Embodiment 4 of the present invention;

[0026] Appendix Figure 6 This is a three-dimensional structural diagram of Embodiment 4 of the present invention;

[0027] Appendix Figure 7 This is a schematic diagram of the horizontal state structure of the flap in Embodiment 4 of the present invention;

[0028] Appendix Figure 8This is a schematic diagram of the structure of Embodiment 5 of the present invention;

[0029] Appendix Figure 9 This is the present invention. Figure 2 A partially enlarged structural diagram of section B in the middle;

[0030] Appendix Figure 10 This is the present invention. Figure 7 A magnified schematic diagram of part C in the middle.

[0031] The following are the labels in the attached diagram: 1. Positioning mechanism; 2. Demolding mechanism; 3. Buffer mechanism; 4. Flip plate; 5. Frame; 6. Sealing box; 11. Horizontal slide rail; 12. Horizontal slide seat; 13. Horizontal movement force mechanism; 14. Positioning fixture; 15. Adjusting motor; 16. Vibration frame; 17. Positioning seat; 21. Extension rail; 22. Extension cylinder; 23. Mounting seat; 24. Air hammer; 25. Adjusting rail; 26. Adjusting mechanism; 31. Hinge; 32. Vibration damping washer; 33. Tightening cylinder; 41. Tilting cylinder; 42. Locking pin; 51. Connecting pin; 52. Locking cylinder; 53. Locking device; 54. Support frame. Detailed Implementation

[0032] The present invention will be further described in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined in this application. Example 1:

[0033] The present invention provides a precision casting sand mold vibration demolding machine, including a frame 5, which serves as the installation position for each actuating component. The frame 5 is made of profile welded together. The left and right sides of the frame 5 serve as the installation positions for the positioning mechanism 1 and the demolding mechanism 2, and the middle part of the two serves as the demolding space.

[0034] Positioning mechanism 1 serves as the fixed position for the casting. Positioning mechanism 1 includes a transverse slide rail 11 and a transverse sliding seat 12 perpendicular to the horizontal plane, with the transverse sliding seat 12 slidably connected to the transverse slide rail 11. A transverse movement force mechanism 13 is installed on one side of the transverse slide rail 11 as the power source. The transverse movement force mechanism 13 uses a synchronous belt drive mechanism, which drives the transverse sliding seat 12 to reciprocate along the transverse slide rail 11 via the synchronous belt. This transverse structure allows the transverse sliding seat 12 to be moved to the outside for easier fixing of the casting, and also allows the vibration action position to change through the displacement of the transverse sliding seat 12, further facilitating vibration demolding.

[0035] A vibration frame 16 is provided on the front side of the transverse sliding seat 12, and a buffer mechanism 3 is provided between the vibration frame 16 and the transverse sliding seat 12. The buffer mechanism 3 between the transverse sliding seat 12 and the vibration frame 16 can reduce the damage of vibration impact to the transverse sliding rail 11 and the transverse moving force mechanism 13. At the same time, its buffering effect can improve the overall vibration amplitude and improve the crushing effect of the sand mold. In this embodiment, the buffer mechanism 3 adopts an array of buffer pads. A positioning seat 17 is rotatably provided in the middle of the vibration frame 16. The bottom surface of the positioning seat 17 is in contact with the vibration frame 16. When the positioning seat 17 is subjected to vibration impact, the vibration frame 16 assists the positioning seat 17 in bearing the impact. Several positioning clamps 14 are provided on the positioning seat 17. The positioning clamps 14 are used to fix the casting. Specifically, the positioning clamps 14 adopt a pressure plate fastened with studs to press and fix the surface of the casting to prevent the casting from falling off. Several T-slots are also provided on the positioning seat 17. The bottom of the stud of the pressure plate cooperates with the T-slot through the T-slide block to realize the position adjustment of the positioning fixture 14, so as to facilitate the fastening of different castings.

[0036] An adjustment motor 15 is installed on the rear side of the transverse sliding seat 12. The adjustment motor 15 is used to drive the positioning seat 17 to rotate. The motor shaft of the adjustment motor 15 is connected to the rotating shaft of the positioning seat 17 through a coupling that drives the clearance, thereby ensuring clearance adjustment during vibration and reducing the hard damage of vibration to the adjustment motor 15.

[0037] The demolding mechanism 2 includes an extension track 21 arranged perpendicular to the transverse sliding seat 12 and an extension cylinder 22. In this embodiment, the extension track 21 is distributed on both sides or the upper and lower bottom surfaces of the frame 5. An mounting seat 23 is slidably mounted on the extension track 21. The extension cylinder 22 is mounted on the frame 5, and the front end of the piston rod of the extension cylinder 22 is fixedly connected to the rear side of the mounting seat 23. Thus, the extension action of the extension cylinder 22 brings the mounting seat 23 closer to the casting. In this embodiment, the extension cylinder 22 is a hydraulic cylinder. The extension distance of the hydraulic cylinder can be controlled by a hydraulic control system, and the extension distance of the extension cylinder 22 can be manually or automatically adjusted according to different castings and their different positions.

[0038] At least one air hammer 24 is installed on the mounting base 23. When the mounting base 23 extends, the air hammer 24 comes into contact with the sand casting fixed on the positioning base 17. The vibration of the air hammer 24 causes the sand shell of the casting to fall off. The extension distance of the extension cylinder 22 is different for different castings and different areas of the casting. The vibration area of ​​the casting is switched by the lateral movement of the transverse seat 12 and the rotation of the positioning base 17. Then, the air hammer 24 vibrates and demolds the casting at different positions, so that the sand shell can fall off stably.

[0039] When using the above-mentioned device for sand mold demolding of precision castings, the transverse moving force mechanism 13 first moves the transverse moving seat 12 to the outside of the transverse moving slide rail 11, and the undemolded precision casting is hoisted and fixed onto the positioning seat 17 by a hoisting device. Then, the transverse moving seat 12 returns to its original position, the mounting seat 23 extends, and the air hammer 24 vibrates against the precision casting to demold the sand mold. After a period of time, the mounting seat 23 retracts a certain distance to provide space for adjusting the position of the casting. The positioning seat 17 rotates a certain angle, and the transverse moving seat 12 moves laterally a certain distance, adjusting the next vibration contact point to the position corresponding to the air hammer 24. Then, the mounting seat 23 advances a corresponding distance, causing the air hammer 24 to contact the new vibration point, continuing the vibration demolding process. By adjusting the angle and position, the vibration amplitude and intensity can be adjusted, allowing for targeted strong vibration of stubborn sand shell attachment points, promoting the breakage and detachment of the sand shell. Adjusting the angle also helps the broken sand shell inside the casting hole to fall off, which is helpful for the subsequent removal of the sand shell and cleaning of the casting. Example 2:

[0040] Compared with Embodiment 1, the specific construction of the buffer mechanism 3 differs in this embodiment. In this embodiment, the buffer mechanism 3 includes a hinge 31 disposed on one side of the transverse seat 12 and the vibration frame 16. The hinge 31 is preferably installed on the top of the transverse seat 12 and the vibration frame 16. The top of the hinge has a limiting member. When the vibration frame 16 is in a vertical state, the bottom surface of the vibration frame 16 abuts against the limiting member, so that when the vibration frame 16 is flipped outward, it can only be flipped to 90 degrees. Several damping washers 32 are installed between the transverse seat 12 and the vibration frame 16. A clamping cylinder 33 is installed on the side of the transverse seat 12 where the hinge 31 is not installed. When the clamping cylinder 33 extends, it abuts against the vibration frame 16, making the vibration frame 16 parallel to the transverse seat 12. At this time, the vibration frame 16 abuts against the limiting member, realizing the vertical positioning of the positioning seat 17.

[0041] After the clamping cylinder 33 clamps the vibrating frame 16, vibration demolding is performed. The air hammer 24 performs rigid high-frequency vibration with high vibration intensity, which can break the sand shell on the surface of the casting. Then the clamping cylinder 33 retracts, so that the vibrating frame 16 is in a relatively relaxed vibration state, its vibration amplitude increases significantly and vibration intensity decreases, "shaking off" the sand shell on it, thus cleaning the sand shell.

[0042] Specifically, with this type of buffer mechanism 3, it is difficult to guarantee the connection distance between the adjusting motor 15 and the positioning seat 17, which can easily cause hard damage to the adjusting motor 15. Therefore, in this embodiment, the motor shaft of the adjusting motor 15 is connected to the positioning seat 17 through a flexible transmission shaft. The transmission shaft provides sufficient buffer space between the adjusting motor 15 and the positioning seat 17, and the flexible connection method can also greatly solve the problem of vibration transmission to the adjusting motor 15, thereby improving the service life of the adjusting motor 15. Example 3:

[0043] For Embodiment 1 or Embodiment 2, multiple air hammers 24 can be provided in this embodiment. Preferably, in this embodiment, two air hammers 24 are symmetrically arranged vertically or horizontally on the mounting base 23. The two air hammers 24 vibrate alternately to demold the sand casting. The alternating vibration mode can increase the vibration frequency and vibration intensity, and better demold the sand mold.

[0044] Furthermore, the mounting base 23 has an adjustment rail 25, and an adjustment mechanism 26 is provided on the rear side of the adjustment rail 25. The adjustment mechanism 26 is driven by a hydraulic cylinder or a synchronous belt and is used to adjust the sliding position of the air hammer 24 on the adjustment rail 25 to adapt it to castings of different specifications. In addition, when the casting structure is complex and the height of the casting surface is not suitable for the simultaneous operation of two air hammers, one of the air hammers 24 can be moved to the outermost edge by the adjustment mechanism 26 to complete the vibration demolding using only one air hammer 24.

[0045] This embodiment provides a dual-pump joint operation method, which can further improve the demolding efficiency and demolding effect of each piece. Furthermore, the displacement adjustment of the two pumps 24 can better adapt to the complex structure of precision castings, enabling them to act on more suitable vibration points and perform targeted vibration demolding operations on stubborn positions of sand mold demolding, thereby improving the demolding effect. Example 4:

[0046] For any of the embodiments in Examples 1 / 2 / 3, this embodiment adds a flipping structure to the frame 5. Specifically, a flip plate 4 is hinged to one side of the frame 5, and the bottom of the flip plate 4 is hinged to the frame 5. Correspondingly, a support frame 54 is provided on the frame 5 behind the flip plate 4. The support frame 54 supports and positions the flip plate 4 after it is flipped, so that the flip plate 4 can be stably supported and kept in a horizontal state. The positioning mechanism 1 is installed on the flip plate 4, and a flipping cylinder 41 is installed between the rear side of the flip plate 4 and the frame 5. The flipping cylinder 41 is a multi-stage telescopic hydraulic cylinder. The flipping cylinder 41 provides power support for the flipping action of the flip plate 4. When the flipping cylinder 41 retracts, the flip plate 4 is in a horizontal state. At this time, the rear side of the flip plate 4 abuts against the support frame 54 and is stably supported by the support frame 54. In this state, it is convenient for loading and unloading precision castings and helps to improve the safety and efficiency of casting positioning and installation. When the tilting cylinder 41 extends, the tilting plate 4 is in a vertical state, at which point the workpiece is erected, which facilitates the direct action of the air hammer 24 and improves the resistance effect of the hydraulic cylinder, effectively supporting the vibration demolding operation.

[0047] Furthermore, to ensure the stability of the flap 4 during vibration demolding, a locking structure is added in this embodiment to lock the flap 4 to the frame 5, fixing them relatively and preventing the flap 4 from resonating under the vibration of the air hammer, which would affect the sand mold crushing effect. A locking pin 42 is provided on the side of the flap 4 that contacts the frame 5, and a mating pin 51 that mates with the locking pin 42 is provided on the side of the frame 5 that contacts the flap 4. Both locking pins 42 are half-shafts, and the mating pin 51 that mates with the locking pin 42 is also a half-shaft. The two can be mated to form a complete pin. A locking cylinder 52 is installed on one side of the docking pin 51. A locking device 53 that slides with the docking pin 51 is installed on the piston shaft of the locking cylinder 52. After being pushed by the locking cylinder 52, the locking device 53 is restricted to the outside of the locking pin 42 and the docking pin 51, thereby realizing the self-locking of the flip plate 4 and the frame 5. This transmits the vibration of the flip plate 4 from the air hammer 24 to the frame 5, reducing the kinetic energy loss of the air hammer 24.

[0048] This embodiment adopts a flipping structure, which changes the steps of picking up and placing castings from a vertical position to a horizontal position, making the positioning, clamping and unloading of large castings simpler and greatly improving safety. Example 5:

[0049] Regarding any of the embodiments 1 / 2 / 3 / 4, this embodiment provides a certain degree of prevention and control for the sand and dust generated during demolding. Specifically, the frame 5 is covered by a sealed box 6. The front of the sealed box 6 has an opening and closing door. When loading and unloading precision castings, the opening and closing door is opened for processing. When demolding precision castings, the opening and closing door is closed for vibration demolding. The front of the opening and closing door has a transparent window to facilitate observation of the working status inside during vibration demolding. The sealed box 6 has a negative pressure dust collection pipeline, which is connected to the workshop's negative pressure dust collection system or a bag filter to collect dust under negative pressure, preventing dust from flying and causing harm to the health of operators.

Claims

1. A precision casting sand mold vibration demolding machine, comprising a frame (5) having a demolding space, characterized in that: A positioning mechanism (1) is provided on one side of the demolding space, and a demolding mechanism (2) is provided on the opposite side of the positioning mechanism (1). The positioning mechanism (1) includes a transverse slide rail (11) and a transverse seat (12) perpendicular to the horizontal plane. The transverse seat (12) is slidably connected to the transverse slide rail (11). A transverse force mechanism (13) for driving the transverse seat (12) to slide back and forth is provided on one side of the transverse slide rail (11). A vibration frame (16) is provided on the front side of the transverse seat (12). (16) A buffer mechanism (3) is provided between the transverse shift seat (12). A positioning seat (17) is rotatably provided in the middle of the vibration frame (16). Several positioning clamps (14) are provided on the positioning seat (17). An adjustment motor (15) is provided on the rear side of the transverse shift seat (12). The adjustment motor (15) is used to drive the positioning seat (17) to rotate. The demolding mechanism (2) includes an extension track (21) arranged perpendicular to the transverse shift seat (12) and an extension cylinder (22). The extension track (21) 1) An upper sliding mounting base (23) is provided, on which at least one air hammer (24) is provided. When the mounting base (23) is extended, the air hammer (24) adapts to the sand casting fixed on the positioning base (17). The buffer mechanism (3) includes a hinge (31) provided on one side of the transverse seat (12) and the vibration frame (16). Several damping washers (32) are provided between the transverse seat (12) and the vibration frame (16). The transverse seat (12) is not equipped with a hinge. (31) A clamping cylinder (33) is provided on one side. When the clamping cylinder (33) extends, it abuts against the vibration frame (16) so that the vibration frame (16) is parallel to the transverse seat (12). The motor shaft of the adjusting motor (15) is connected to the positioning seat (17) through a transmission flexible shaft. When the clamping cylinder (33) clamps the vibration frame (16), the air hammer (24) performs rigid high-frequency vibration. When the clamping cylinder (33) contracts, the vibration frame (16) is in a relatively loose vibration state.

2. The precision casting sand mold vibration demolding machine according to claim 1, characterized in that: Two air hammers (24) are provided, and the two air hammers (24) vibrate alternately to achieve demolding of sand castings.

3. The precision casting sand mold vibration demolding machine according to claim 2, characterized in that: An adjustment track (25) is provided on the mounting base (23), and an adjustment mechanism (26) is provided on the rear side of the adjustment track (25). The air hammer (24) is slidably connected to the adjustment track (25), and the adjustment mechanism (26) is used to drive the air hammer (24) to slide along the adjustment track (25).

4. A precision casting sand mold vibration demolding machine according to claim 1, characterized in that: The frame (5) is hinged to a flap (4), the bottom of the flap (4) is hinged to the frame (5), the positioning mechanism (1) is installed on the flap (4), and a flipping cylinder (41) is provided between the rear side of the flap (4) and the frame (5). When the flipping cylinder (41) retracts, the flap (4) is in a horizontal state, and when the flipping cylinder (41) extends, the flap (4) is in a vertical state.

5. A precision casting sand mold vibration demolding machine according to claim 4, characterized in that: A locking pin (42) is provided on the side of the flap (4) that contacts the frame (5). A mating pin (51) that cooperates with the locking pin (42) is provided on the side of the frame (5) that contacts the flap (4). A locking cylinder (52) is provided on one side of the mating pin (51). A locking device (53) that slides with the mating pin (51) is provided on the piston shaft of the locking cylinder (52). The locking device (53) is restricted to the outside of the locking pin (42) and the mating pin (51) after being pushed by the locking cylinder (52).

6. A precision casting sand mold vibration demolding machine according to claim 4, characterized in that: The frame (5) on the rear side of the flip plate (4) has a support frame (54). When the flip plate (4) is retracted, the rear side of the flip plate (4) abuts against the support frame (54) so ​​that the flip plate (4) is in a horizontal state.

7. A precision casting sand mold vibration demolding machine according to any one of claims 1-6, characterized in that: The frame (5) is covered by a sealed box (6) on the outside, and the sealed box (6) has an opening and closing door on the front side.

8. A precision casting sand mold vibration demolding machine according to claim 7, characterized in that: The sealed box (6) has a negative pressure dust removal pipeline for collecting dust under negative pressure.

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