A dewaxing device for investment casting of annular workpieces

Abstract

The present invention relates to the field of mechanical processing technology, and specifically to a dewaxing device for investment casting of annular workpieces, comprising a frame, a lifting mechanism and a water tank; the annular workpiece is mounted outside the workpiece fixture, the workpiece fixture is mounted on the lifting mechanism through a support frame, the lifting mechanism is mounted on the upper rear side of the frame, the water tank is mounted at the lower part of the frame to receive the annular workpiece, and the lifting mechanism drives the annular workpiece to move vertically up and down, realizing the switching between the material taking and unloading station away from the water tank and the processing station immersed in the water tank. The position of the material taking and unloading station of the present invention is separated from the high-temperature water tank to avoid high temperature injuries, the trapezoidal screw has a self-locking ability to prevent the workpiece from falling during the lifting process, the guide groove and the cam follower facilitate the installation and rotation of the workpiece, the circulating water is combined with the adjustable plastic cooling pipe to blow air toward the filter tank, so that the wax liquid floating on the water surface moves toward the filter tank and is filtered and recovered through the filter screen.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing, in particular to a dewaxing device used for investment casting of annular workpieces. Background Art

[0002] Investment casting is a common metal forming process in the machining industry. Also known as "lost wax casting," investment casting typically involves forming a pattern from a fusible material. Several layers of refractory material are then coated on the pattern to form a mold shell. The pattern is then melted and ejected from the shell, resulting in a mold without a parting surface. After high-temperature firing, the mold can be filled with sand and poured. Because the pattern is often made of wax, investment casting is often referred to as "lost wax casting." As a metal forming process, investment casting can produce extremely complex parts. Compared to die casting, sand casting, and lost foam casting, investment casting allows for the highest degree of part complexity. During the machining of high-precision annular workpieces, the workpiece spokes are usually hollow structures. The wax liquid after investment casting is sealed in the workpiece, and drainage holes are reserved on the workpiece. Since the drainage holes are usually located close to the middle of the workpiece, if it is placed flat in a hot water tank, the wax liquid below the drainage holes will remain in the inner cavity of the workpiece and cannot be completely discharged. At the same time, the discharged wax liquid will float on the water surface. When the workpiece is taken out, the wax liquid will adhere to the surface of the workpiece, causing secondary contamination to the workpiece. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a dewaxing device for investment casting of annular workpieces.

[0004] The specific technical solutions are as follows:

[0005] A dewaxing device for investment casting of an annular workpiece comprises a frame, a lifting mechanism, and a water tank; the annular workpiece is mounted on a workpiece fixture having a centrally extending shaft, the workpiece fixture being mounted on the lifting mechanism via a support frame, the lifting mechanism being mounted above the rear side of the frame; the water tank is mounted at the lower portion of the frame to receive the annular workpiece, and comprises a processing tank and a filtering tank arranged horizontally and side by side, the processing tank and the filtering tank being separated by a partition plate, the partition plate having an overflow notch in the middle;

[0006] The bottom surfaces of the processing tank and the filter tank are both V-shaped structures; the bottom of the filter tank is connected to the water inlet of the centrifugal pump via a pipe, and the water outlet of the centrifugal pump is connected in sequence to the switch valve, the filter, and the overflow pipe, which is connected to the top of the processing tank on the side opposite to the partition plate; a removable filter screen is installed on the top of the filter tank; heaters are installed at the corners on both sides of the overflow pipe of the processing tank, and temperature sensors are installed at the other two corners;

[0007] The lifting mechanism drives the annular workpiece to move vertically up and down, thereby realizing the switching between the material taking and placing station leaving the water tank and the processing station immersed in the water tank.

[0008] The frame is a frame formed by welding square steel pipes, and four footings are arranged at the bottom of the frame; and heat-insulating materials are filled between the frame and the equipment cover.

[0009] The installation height of the filter screen is such that the upper edge of the filter screen is lower than the overflow notch of the partition plate.

[0010] The filter screen is a detachable structure with a porous structure at the bottom and handles provided on both sides of the top, which can be hung on the top of the filter tank through hooks.

[0011] An adjustable plastic cooling pipe is arranged above the overflow water pipe of the processing tank, and the adjustable plastic cooling pipe is connected with an air source to blow air toward the filter tank.

[0012] The lifting mechanism includes a servo motor, a trapezoidal screw, a guide shaft, an adapter plate and a linear bearing; the trapezoidal screw is vertically arranged in the middle position of the lifting mechanism, and the trapezoidal screw is fixed to the frame by respectively arranging a screw support 1 and a screw support 2 at the upper and lower positions of the frame, a servo motor is arranged at the bottom of the trapezoidal screw, the servo motor is fixed to the frame through a motor adapter plate, and the output shaft of the servo motor is connected to the trapezoidal screw through a coupling; a guide shaft is vertically arranged on each side of the trapezoidal screw, and two guide shaft support seats are used to vertically fix the guide shaft to the frame; a screw adapter block is arranged on the nut of the trapezoidal screw, and the adapter plate is respectively connected to the linear bearing and the screw adapter plate, and an upper limit block and a lower limit block are respectively arranged at the upper and lower positions of one side of the adapter plate.

[0013] Photoelectric switch brackets are respectively arranged near the upper and lower limit positions of the trapezoidal lead screw of the frame, and the upper and lower photoelectric switch brackets are respectively provided with a photoelectric switch 2 and a photoelectric switch 1.

[0014] The support frame is a parallel and symmetrical double-layer structure, connected to the front side of the adapter plate. The front end of the support frame is horizontal and has a guide groove for placing the extended shaft of the workpiece fixture 4.

[0015] The upper portion of the guide groove is a V-shaped notch, and the lower portion is processed with a circular groove. Two cam followers are arranged on the outer side of the support frame near the circular groove.

[0016] The frame, processing tank, filter tank and filter screen are made of SUS304 or higher grade stainless steel.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects:

[0018] The device of the present invention has a simple structure. The position of the material taking and unloading station is separated from the high-temperature water tank to avoid high temperature injury. The trapezoidal screw has a self-locking ability to prevent the workpiece from falling during the lifting process. The V-shaped guide groove structure and the cam follower facilitate the installation and rotation of the workpiece and have a high fault tolerance rate. A centrifugal pump and other components are used to circulate water and an adjustable plastic cooling pipe is used to blow air toward the filter tank, so that the wax liquid floating on the water surface gradually moves toward the filter tank, and the wax liquid is filtered and recovered through a detachable filter screen arranged on the top of the filter tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the three-dimensional structure of the dewaxing equipment of the present invention;

[0020] Figure 2 This is a rear view of the dewaxing equipment of the present invention;

[0021] Figure 3 This is a left side view of the dewaxing equipment of the present invention;

[0022] Figure 4 A top view of the dewaxing equipment of the present invention;

[0023] Figure 5 This is a schematic diagram of the material loading and unloading stations of the dewaxing equipment of the present invention;

[0024] Figure 6 This is a schematic diagram of the processing station of the dewaxing equipment of the present invention.

[0025] Figure: 1. Frame; 2. Annular workpiece; 3. Support frame; 4. Workpiece fixture; 5. Cam follower; 6. Guide shaft support; 7. Screw support (1); 8. Trapezoidal screw; 9. Guide shaft; 10. Screw adapter block; 11. Adapter plate; 12. Nut; 13. Motor adapter plate; 14. Servo motor; 15. Filter; 16. Foot; 17. Centrifugal pump; 18. Switch valve; 19. Coupling; 20. Screw support (2); 21. , photoelectric switch 1; 22. Lower limit baffle; 23. Linear bearing; 24. Upper limit baffle; 25. Photoelectric switch 2; 26. Photoelectric switch bracket; 27. Overflow water pipe; 28. Adjustable plastic cooling pipe; 29. ​​Heater; 30. Temperature sensor; 31. Filter screen; 32. Water tank; 33. Processing tank; 34. Filter tank; 35. Partition plate; 36. Overflow notch; 37. Pipeline; 38. Guide groove; 39. Extending shaft. DETAILED DESCRIPTION

[0026] The present invention will be described in detail below with reference to the accompanying drawings, but the protection scope of the present invention is not limited by the accompanying drawings.

[0027] Figure 1 This is a schematic diagram of the three-dimensional structure of the dewaxing equipment of the present invention. Figure 2 This is the rear view of the dewaxing equipment of the present invention. Figure 3 This is the left side view of the dewaxing equipment of the present invention. Figure 4 This is a top view of the dewaxing equipment of the present invention, as shown in the figure.

[0028] The present invention is a dewaxing device for investment casting of an annular workpiece, comprising a frame 1, a lifting mechanism and a water tank 32; the frame 1 is a frame formed by welding square steel pipes, and four footings 16 are provided at the bottom of the frame 1 for supporting the device; thermal insulation material is filled between the frame 1 and the device cover to reduce temperature loss and reduce resource waste.

[0029] The annular workpiece 2 is mounted on a workpiece fixture 4 with a protruding shaft 39 at the center. The workpiece fixture 4 is mounted on a lifting mechanism through a support frame 3. The lifting mechanism is mounted on the upper rear side of the frame 1. The water tank 32 is mounted at the lower part of the frame 1 to receive the annular workpiece 2. It includes a processing tank 33 and a filter tank 34 arranged horizontally in parallel. The processing tank 33 and the filter tank 34 are separated by a partition plate 35. An overflow notch 36 is provided in the middle of the partition plate 35. The bottom surfaces of the processing tank 33 and the filter tank 34 are both V-shaped structures. The bottom of the filter tank 34 is connected to the water inlet of the centrifugal pump 17 through a pipe 37. The water outlet of the centrifugal pump 17 is connected to the switch valve 18, the filter 15 and the overflow pipe 27 in sequence. The overflow water pipe 27 is connected to the top of the processing tank 33 and the opposite side of the partition plate 35; a detachable filter screen 31 is installed on the top of the filter tank 34. The filter screen 31 is a detachable structure with a porous structure at the bottom. Handles are provided on both sides of the top and are hung on the top of the filter tank 34 through hooks. The installation height of the filter screen 31 makes the upper edge of the filter screen 31 lower than the overflow notch 36 of the partition plate 35; heaters 29 are provided at the corners on both sides of the overflow water pipe 27 of the processing tank 33, and temperature sensors 30 are provided at the other two corners; an adjustable plastic cooling pipe 28 is provided above the overflow water pipe 27 of the processing tank 33. The adjustable plastic cooling pipe 28 is connected to the air source to blow air toward the filter tank 34.

[0030] The lifting mechanism drives the annular workpiece 2 to move vertically up and down, realizing the switching between the material taking and placing station leaving the water tank 32 and the processing station immersed in the water tank 32. The lifting mechanism includes a servo motor 14, a trapezoidal screw 8, a guide shaft 9, an adapter plate 11 and a linear bearing 23; the trapezoidal screw 8 is vertically arranged in the middle position of the lifting mechanism, and the trapezoidal screw 8 is fixed to the frame 1 by respectively arranging a screw support 1 7 and a screw support 2 20 at the upper and lower positions of the frame 1, and a servo motor 14 is arranged at the bottom of the trapezoidal screw 8, and the servo motor 14 is fixed to the frame 1 through the motor adapter plate 13, and the output shaft of the servo motor 14 is connected to the trapezoidal screw 8 through the coupling 19; a guide shaft 9 is vertically arranged on each side of the trapezoidal screw 8, and two guide shaft support seats 6 are used to vertically fix the guide shaft 9 to the frame 1; a screw adapter block 10 is arranged on the nut 12 of the trapezoidal screw 8, and the adapter plate 11 is respectively connected to the linear bearing 23 and the screw adapter plate 10, and an upper limit baffle 24 and a lower limit baffle 22 are respectively arranged at the upper and lower positions on one side of the adapter plate 11. Photoelectric switch brackets 26 are respectively provided near the upper and lower limit positions of the trapezoidal lead screw 8 of the frame 1 , and the upper and lower photoelectric switch brackets 26 are respectively provided with a photoelectric switch 2 25 and a photoelectric switch 1 21 .

[0031] The support frame 3 is a parallel, symmetrical, double-layer structure connected to the front side of the adapter plate 11. The front end of the support frame 3 is horizontal and has a guide slot 38 for accommodating the extended shaft 39 of the workpiece fixture 4. The guide slot 38 has a V-shaped notch above and a circular groove below. Two cam followers 5 are located on the outside of the support frame 3 near the circular groove.

[0032] The above frame 1, processing tank 33, filter tank 34 and filter screen 31 are made of SUS304 or higher grade stainless steel.

[0033] When working, at the material loading and unloading station (such as Figure 5 As shown in the figure, the annular workpiece 2 is mounted on the workpiece fixture 4. The annular workpiece 2 and the workpiece fixture 4 are hoisted together by a crane. The extended shafts 39 at both ends of the workpiece fixture 4 are placed in the guide grooves 38 at the front end of the support frame 3. First, the annular workpiece 2 is driven by the lifting mechanism to be immersed in the processing tank 33 filled with sufficient water. This is the processing station (as shown in the figure). Figure 6The heater 29 is started. When the water temperature reaches the set temperature, a high-temperature resistant round rod is used to slowly push the annular workpiece 2 to rotate around the axis of the workpiece fixture 4, depending on the structural differences of the annular workpiece 2. This causes the wax liquid in the inner cavity of the annular workpiece 2 to flow out. Since the density of the wax liquid is lower than that of water, the outflowing wax liquid will float on the upper surface of the water in the processing tank 33. The overflow water pipe 27 connected to the centrifugal pump 17 is used to circulate water, and the adjustable plastic cooling pipe 28 is used to blow air toward the filter tank 34, so that the wax liquid floating on the water surface gradually moves toward the filter tank 34, thereby achieving the dewaxing treatment of the annular workpiece 2. At the same time, the wax liquid can be filtered and recovered through the detachable filter screen 31 set at the top of the filter tank 34.

Claims

1. A dewaxing device for investment casting of annular workpieces, characterized by: The invention comprises a frame (1), a lifting mechanism and a water tank (32); the annular workpiece (2) is mounted on a workpiece fixture (4) with a protruding shaft (39) at the center; the workpiece fixture (4) is mounted on the lifting mechanism via a support frame (3); the lifting mechanism is mounted above the rear side of the frame (1); the water tank (32) is mounted at the lower part of the frame (1) to receive the annular workpiece (2); the water tank (32) comprises a processing tank (33) and a filtering tank (34) arranged horizontally and in parallel; the processing tank (33) and the filtering tank (34) are separated by a partition plate (35); an overflow notch (36) is provided in the middle of the partition plate (35); The bottom surfaces of the processing tank (33) and the filter tank (34) are both V-shaped structures; the bottom of the filter tank (34) is connected to the water inlet of the centrifugal pump (17) through a pipe (37); the water outlet of the centrifugal pump (17) is connected to the switch valve (18), the filter (15) and the overflow pipe (27) in sequence; the overflow pipe (27) communicates with the top of the processing tank (33) on the opposite side of the partition plate (35); a detachable filter screen (31) is installed on the top of the filter tank (34); heaters (29) are set at the corners on both sides of the overflow pipe (27) of the processing tank (33), and temperature sensors (30) are set at the other two corners; The lifting mechanism drives the annular workpiece (2) to move vertically up and down, realizing the switching between the material taking-out station leaving the water tank (32) and the processing station immersed in the water tank (32); The installation height of the filter screen (31) is such that the upper edge of the filter screen (31) is lower than the overflow notch (36) of the partition plate (35); The filter screen (31) is a detachable structure, with a porous structure at the bottom and handles on both sides of the top, which can be hung on the top of the filter tank (34) through a hook; An adjustable plastic cooling pipe (28) is provided above the overflow water pipe (27) of the processing tank (33), and the adjustable plastic cooling pipe (28) is connected to an air source to blow air toward the filter tank (34); The lifting mechanism comprises a servo motor (14), a trapezoidal screw (8), a guide shaft (9), an adapter plate (11) and a linear bearing (23); the trapezoidal screw (8) is vertically arranged in the middle position of the lifting mechanism, and the trapezoidal screw (8) is fixed to the frame (1) by respectively arranging a screw support 1 (7) and a screw support 2 (20) at the upper and lower positions of the frame (1), and a servo motor (14) is arranged at the bottom of the trapezoidal screw (8), and the servo motor (14) is fixed to the frame (1) through the motor adapter plate (13) (11), and the coupling (1 9) connecting the output shaft of the servo motor (14) to the trapezoidal lead screw (8); a guide shaft (9) is vertically arranged on each side of the trapezoidal lead screw (8), and two guide shaft (9) support seats (6) are used to vertically fix the guide shaft (9) on the frame (1); a lead screw adapter block (10) is arranged on the nut (12) of the trapezoidal lead screw (8), and the adapter plate (11) is respectively connected to the linear bearing (23) and the lead screw adapter plate (11), and an upper limit stopper (24) and a lower limit stopper (22) are respectively arranged at the upper and lower positions of one side of the adapter plate (11).

2. The dewaxing equipment for investment casting of annular workpieces according to claim 1, characterized in that: The frame (1) is a frame formed by welding square steel pipes, and four footings (16) are provided at the bottom of the frame (1); and thermal insulation material is filled between the frame (1) and the equipment outer cover.

3. The dewaxing equipment for investment casting of annular workpieces according to claim 1, characterized in that: Photoelectric switch brackets (26) are respectively arranged near the upper and lower limit positions of the trapezoidal lead screw (8) of the frame (1), and the upper and lower photoelectric switch brackets (26) are respectively provided with a photoelectric switch 2 (25) and a photoelectric switch 1 (21).

4. The dewaxing equipment for investment casting of annular workpieces according to claim 1, characterized in that: The support frame (3) is a parallel symmetrical double-layer structure connected to the front side of the adapter plate (11). The front end of the support frame (3) is horizontal and has a guide groove (38) for placing the extended shaft (39) of the workpiece fixture (4).

5. The dewaxing equipment for investment casting of annular workpiece according to claim 4, characterized in that: The upper portion of the guide groove (38) is a V-shaped notch, and the lower portion is processed with a circular groove. Two cam followers (5) are arranged on the outer side of the support frame (3) near the circular groove.

6. The dewaxing equipment for investment casting of annular workpiece according to claim 1, characterized in that: The frame (1), processing tank (33), filter tank (34) and filter screen (31) are made of SUS304 stainless steel.

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