Diamond grinding wheel and cold press molding device thereof

Abstract

The invention relates to a diamond grinding wheel and a cold press forming device of the diamond grinding wheel. The problems that the cooling effect of the diamond grinding wheel cold press forming device is poor, and a grinding wheel abrasive layer is prone to ring disengaging are effectively solved. The grinding wheel base body is designed into the outer ring body of the thin-wall structure and the two cone-shaped bodies of the inner sleeve, in the practical process of the grinding wheel, the cone-shaped bodies and the outer ring body are combined into a whole, and the structural strength of the grinding wheel base body and the function of the grinding wheel are not affected. During compression molding, a wall-attached cooling liquid flow is formed on the inner wall of the outer ring body through small-amplitude separation of the conical body and the outer ring body, effective heat dissipation is carried out on the bonding surface of the grinding material and the base body, and the problems of sintering deformation, cracking and even ring disengaging are avoided.

Description

Technical Field

[0001] This invention relates to the field of diamond grinding wheels, specifically a diamond grinding wheel and a cold pressing forming apparatus for the grinding wheel. Background Technology

[0002] Diamond grinding wheels are abrasives made from diamond abrasives and bonded to a substrate by means of metal powder, resin powder, ceramics and electroplated metals. During the cold pressing process, as the pressure increases, the temperature at the junction of the abrasive layer and the substrate rises, which can easily lead to sintering deformation, cracking or even delamination.

[0003] The invention patent application number CN202310139837.3 discloses a cold pressing forming device for producing metal-bonded diamond grinding wheels. It has a heat exchange chamber set outside the forming cavity. During the cold pressing forming process, the grinding wheel is cooled by the coolant in the heat exchange chamber. However, in actual use, it was found that the heat exchange chamber is set outside the abrasive layer. Since the abrasive layer is relatively thick, the cooling chamber is far from the bonding part between the abrasive layer and the substrate. Therefore, the heat dissipation efficiency at the bonding part is poor, and the cooling effect does not meet expectations.

[0004] In addition, the outer wall of the grinding wheel substrate formed by the above-mentioned patent is cylindrical, which does not limit the abrasive layer. When the adhesion between the abrasive layer and the substrate decreases or fails, the abrasive layer is prone to sudden detachment during the grinding process, which may cause workpiece damage or worker safety accidents. Summary of the Invention

[0005] This invention provides a diamond grinding wheel and a cold pressing forming device for the grinding wheel, aiming to solve the problems of poor cooling effect and easy detachment of the abrasive layer of the grinding wheel in the cold pressing forming device for diamond grinding wheels.

[0006] The technical solution is as follows: A diamond grinding wheel is disclosed, comprising an abrasive layer and a substrate. The abrasive layer is fixed to the outer wall of the substrate. The substrate includes an outer ring and two conical bodies. The inner wall of the outer ring is composed of two upper and lower conical segments connected at their small ends. The two conical bodies are coaxially mounted within the two conical segments. When the two conical bodies move in opposite directions, a gap is formed between the outer wall of the conical body and the inner wall of the conical segment. Each conical body has a shaft hole at its axis, through which a rotating shaft is inserted. Two sets of nuts are screwed onto the rotating shaft, located on the upper and lower sides of the substrate, respectively. When the two nuts are tightened, the outer walls of both conical bodies are in close contact with the inner walls of their respective conical segments.

[0007] The conical body has radial channels on its sidewalls, and these channels are connected to the shaft hole.

[0008] Each of the cones has a shallow circular groove coaxially formed at its small end.

[0009] Both the large end of the conical section and the large end of the conical body are provided with a straight cylindrical section. During the axial movement of the conical body, the outer wall of the straight cylindrical section of the conical body and the inner wall of the straight cylindrical section of the conical section are always in a close and sealed state.

[0010] The outer ring body has multiple axial grooves evenly distributed around its circumference on each end face, and the cone body has multiple axial blocks evenly distributed around its large end face sidewall, with each axial block corresponding to and embedded in the axial groove.

[0011] The outer wall of the outer ring is parallel to the inner wall.

[0012] The outer ring has several raised strips evenly distributed around its outer circumference, parallel to the generatrix.

[0013] A cold pressing forming device for a grinding wheel includes an upper mold and a lower mold. The lower mold is a cylindrical shape with an open top. A first stepped groove is coaxially formed on the inner bottom surface of the lower mold. A second stepped groove is coaxially formed on the bottom surface of the first stepped groove. A first rubber pad is installed in the second stepped groove. A water inlet pipe is installed at the axis of the lower mold and passes through the bottom surface of the lower mold and the first rubber pad. The upper mold is a circular flat plate with the same outer diameter as the inner diameter of the lower mold. A third stepped groove is coaxially opened on the lower surface of the upper mold, and a fourth stepped groove is coaxially opened on the bottom surface of the third stepped groove. A second rubber pad is installed in the fourth stepped groove. A water outlet pipe is installed at the axis of the upper mold, which passes through the upper mold and the second rubber pad. A pressure valve is installed on the water outlet pipe. A hydraulic cylinder is installed at the top of the upper mold.

[0014] This invention designs the grinding wheel substrate as a thin-walled outer ring and two inner conical bodies. During the practical application of the grinding wheel, the conical bodies and the outer ring are combined into a whole, without affecting the structural strength of the grinding wheel substrate or the function of the grinding wheel. During pressing and molding, the small-amplitude separation between the conical bodies and the outer ring forms a wall-mounted cooling liquid flow on the inner wall of the outer ring, which effectively dissipates heat from the interface between the abrasive and the substrate, avoiding problems such as sintering deformation, cracking, or even ring detachment.

[0015] The outer ring of this invention has a V-shaped generatrix. This shape of the outer wall can increase the bonding area with the abrasive layer and can axially compress and limit the abrasive layer, thereby improving the bonding strength between the abrasive layer and the outer ring. In addition, the protruding strips on the outer wall of the outer ring can circumferentially limit the abrasive layer. Even if the bonding strength between the abrasive layer and the substrate decreases, the abrasive layer will not shift or detach from the ring, thus avoiding damage to the workpiece or safety accidents to workers. Attached Figure Description

[0016] Figure 1 This is the front sectional view of the grinding wheel.

[0017] Figure 2 This is a three-dimensional view of the outer ring.

[0018] Figure 3 This is a three-dimensional diagram of a cone.

[0019] Figure 4 For the three-dimensional shape of the grinding wheel Figure 1 .

[0020] Figure 5 For the three-dimensional shape of the grinding wheel Figure 2 .

[0021] Figure 6 This is an assembly diagram of the grinding wheel.

[0022] Figure 7 This is a front sectional view of the grinding wheel and cold pressing device.

[0023] Figure 8 for Figure 7 A magnified view of position A in the middle.

[0024] Figure 9 This is a three-dimensional view of the lower mold.

[0025] Figure 10 This is a 3D view of the upper mold.

[0026] Figure 11 Three-dimensional cold pressing device Figure 1 .

[0027] Figure 12 This is an assembly drawing of the grinding wheel and cold pressing device. Detailed Implementation

[0028] A diamond grinding wheel includes an abrasive layer 1 and a substrate 2. The abrasive layer 1 is fixed to the outer wall of the substrate 2. The substrate 2 includes an outer ring 3 and two conical bodies 4. The inner wall of the outer ring 3 is composed of two upper and lower conical segments connected at their small ends. The two conical bodies 4 are coaxially mounted within the two conical segments. When the two conical bodies 4 move in opposite directions, a gap is formed between the outer wall of the conical body 4 and the inner wall of the conical segment. During pressing and molding, coolant can enter this gap to cool the outer ring 3 and the abrasive layer 4. The material bonding area is continuously cooled; each conical body 4 has a shaft hole 5 at its axis, and a rotating shaft 6 is inserted into the shaft hole 5. Two sets of nuts 7 are screwed on the rotating shaft 6. The two sets of nuts 7 are located on the upper and lower sides of the base body 2 respectively. When the two nuts 7 are tightened, the outer wall of the two conical bodies 4 is close to the inner wall of the conical section, so that the base body 2 forms a whole. The rotating shaft 6 is connected to the conical body 4 by a flat key or spline, and the rotating shaft 6 drives the grinding wheel to perform grinding operations.

[0029] The conical body 4 has radial channels 8 on its sidewalls, which are connected to the shaft hole 5. During pressing, coolant flows in from the shaft hole 5 of the lower conical body 4 and, under the pressure of the coolant, pushes the two conical bodies 4 to move in opposite directions, thus forming a gap. Part of the coolant flows into the gap between the lower conical body 4 and the conical segment through the channel 8 on the lower conical body 4, and part of the coolant enters the gap between the upper conical body 4 and the conical segment and flows through the channel 8 on the upper conical body 4 to the shaft hole 5 on the upper conical body 4. Finally, it flows out from the upper end of the shaft hole 5, forming a continuous flow of coolant, which continuously cools the outer ring body 3 and the abrasive joint.

[0030] Each of the cones 4 has a shallow circular groove 9 coaxially formed at its small end. Before the small end faces of the two cones 4 are separated, the bottom surface of the shallow groove 9 serves as the surface on which the coolant pressure acts, ensuring that the two cones 4 can be pushed apart.

[0031] Both the large end of the conical section and the large end of the conical body 4 are provided with a straight cylindrical section. During the axial movement of the conical body 4, the outer wall of the straight cylindrical section of the conical body 4 and the inner wall of the straight cylindrical section of the conical section are always in a close and sealed state, so that the coolant cannot overflow from the outer end of the gap.

[0032] The outer ring body 3 has multiple axial grooves 10 evenly distributed around its circumference on each end face, and the cone body 4 has multiple axial blocks 11 evenly distributed around its circumference on the side wall of its large end face. The axial blocks 11 are embedded one-to-one into the axial grooves 10 to limit the cone body 4 and the outer ring body 3 in the circumferential direction, so that the cone body 4 and the outer ring body 3 cannot rotate relative to each other.

[0033] The outer wall of the outer ring body 3 is parallel to the inner wall, that is, the generatrix of the outer ring body 3 is V-shaped. This shape of the outer wall can increase the bonding area with the abrasive layer 1, and can axially compress and limit the abrasive layer 1, thereby improving the bonding strength between the abrasive layer 1 and the outer ring body 3.

[0034] The outer ring body 3 has several raised strips 12 evenly distributed around its outer circumference, which are parallel to the generatrix. The raised strips 12 can limit the abrasive layer 1 in the circumferential direction.

[0035] A cold pressing forming device for a grinding wheel includes an upper mold 13 and a lower mold 14. The lower mold 14 is a cylindrical shape with an open upper end. A first stepped groove 15 is coaxially formed on the inner bottom surface of the lower mold 14. A second stepped groove 16 is coaxially formed on the bottom surface of the first stepped groove 15. A first rubber pad 17 is installed in the second stepped groove 16. A water inlet pipe 18 is installed at the axis of the lower mold 14, and the water inlet pipe 18 passes through the bottom surface of the lower mold 14 and the first rubber pad 17. The upper mold 13 is a circular flat plate. The outer diameter of the upper mold 13 is the same as the inner diameter of the lower mold 14. A third stepped groove 19 is coaxially opened on the lower surface of the upper mold 13. A fourth stepped groove 20 is coaxially opened on the bottom surface of the third stepped groove 19. A second rubber pad 21 is installed in the fourth stepped groove 20. A water outlet pipe 22 is installed at the axis of the upper mold 13. The water outlet pipe 22 passes through the upper mold 13 and the second rubber pad 21. A pressure valve 23 is installed on the water outlet pipe 22. A hydraulic cylinder 24 is provided at the top of the upper mold 13 for lifting and pressing the upper mold 13.

[0036] When the above-mentioned grinding wheel is pressed using the cold pressing forming device, the conical body 4 is installed inside the outer ring body 3, without the rotating shaft 6 and nut 7 installed. Then, it is placed into the lower mold 14 and is coaxial with the lower mold 14. The lower end face of the outer ring body 3 abuts against the bottom surface of the first stepped groove 15 and the outer wall of the outer ring body 3 is in contact with the inner wall of the first stepped groove 15. The lower conical body 4 is pressed on the first rubber pad 17. The water inlet pipe 18 is inserted into the lower end of the shaft hole 5 on the lower conical body 4. Then, abrasive is added and flattened in the annular cavity between the outer ring body 3 and the inner wall of the lower mold 14. Then, the hydraulic cylinder 24 pushes the upper mold 13 down. The upper end face of the outer ring body 3 abuts against the bottom surface of the third stepped groove 19 and the outer wall of the outer ring body 3 is in contact with the inner wall of the third stepped groove 19. The outer ring body 3 is completely limited and fixed. The upper conical body 4 is pressed on the second rubber pad 21. The water outlet pipe 22 is inserted into the upper end of the shaft hole 5 on the upper conical body 4.

[0037] Coolant is pumped into the inlet pipe 18 and enters between the end faces of the two cones 4. The hydraulic pressure of the coolant first acts on the end face of the shallow tank 9, pushing the two cones 4 to move in opposite directions. The end faces of the two cones 4 separate, and the hydraulic pressure can then act on the end faces of the cones 4. The hydraulic pressure pushes the lower cone 4 downward and the upper cone 4 upward, causing the first rubber pad 17 and the second rubber pad 21 to be axially compressed and deformed respectively. When the hydraulic pressure rises to the threshold of the pressure valve 23, the pressure valve 23 opens, and the outlet pipe 22 begins to drain water. At this time, the two cones 4 are kept in a state of separation under the force balance of the hydraulic pressure and the elasticity of the rubber pads.

[0038] After the two cones separate, a gap appears between the outer wall of cone 4 and the inner wall of outer ring 3. Some coolant flows into the gap between the lower cone 4 and the cone section through channel 8 on the lower cone 4, while some coolant enters the gap between the upper cone 4 and the cone section and flows through channel 8 on the upper cone 4 to the shaft hole 5 on the upper cone 4, finally flowing out from the upper end of the shaft hole 5, forming a continuous coolant flow. Figure 7 As shown by the middle arrow, the outer ring 3 and the abrasive bonding area are continuously cooled.

[0039] The hydraulic cylinder 24 pressurizes the abrasive in the mold to form a mold. During the pressing process, the hydraulic pressure in the outer ring sleeve will maintain the supporting force on the outer ring body 3. The gap between the cone body 4 and the outer ring body 3 is small, and the amount of coolant that can be compressed in the gap is small. The cone body 4 also has a limiting effect on the deformation of the outer ring body 3. Therefore, the outer ring body 3 will not undergo excessive deformation under the forming pressure due to its thin-walled structure.

[0040] This invention designs the grinding wheel base 2 as a thin-walled outer ring 3 and two inner conical bodies 4. During the practical use of the grinding wheel, the conical bodies 4 and the outer ring 3 are combined into a whole, without affecting the structural strength of the grinding wheel base 2 or the function of the grinding wheel. During the pressing and molding process, the conical bodies 4 and the outer ring 3 are slightly separated to form a wall-mounted cooling liquid flow on the inner wall of the outer ring 3, which effectively dissipates heat from the interface between the abrasive and the base 2, avoiding problems such as sintering deformation, cracking, or even ring detachment.

[0041] The outer ring 3 of the present invention has a V-shaped generatrix. This shape of the outer wall can increase the bonding area with the abrasive layer 1 and can axially compress and limit the abrasive layer 1, thereby improving the bonding strength between the abrasive layer 1 and the outer ring 3. In addition, the protruding strip 12 on the outer wall of the outer ring 3 can circumferentially limit the abrasive layer 1. Even if the bonding strength between the abrasive layer 1 and the substrate 2 decreases, the abrasive layer 1 will not shift or detach from the ring, thus avoiding damage to the workpiece or safety accidents to workers.

Claims

1. A diamond grinding wheel, comprising an abrasive layer (1) and a substrate (2), wherein the abrasive layer (1) is fixed to the outer wall of the substrate (2), characterized in that, The base (2) includes an outer ring (3) and two cones (4). The inner wall of the outer ring (3) is composed of two upper and lower cone segments. The small ends of the two cone segments are connected. The two cones (4) are coaxially installed in the two cone segments respectively. When the two cones (4) move in opposite directions, a gap will be formed between the outer wall of the cone (4) and the inner wall of the cone segment. Each cone (4) has a shaft hole (5) at its axis. A rotating shaft (6) is inserted in the shaft hole (5). Two sets of nuts (7) are screwed on the rotating shaft (6). The two sets of nuts (7) are located on the upper and lower sides of the base (2) respectively. When the two nuts (7) are tightened, the outer walls of the two cones (4) are close to the inner wall of the cone segment.

2. The diamond grinding wheel according to claim 1, characterized in that, The conical body (4) has a radial channel (8) on its side wall, and the channel (8) is connected to the shaft hole (5).

3. A diamond grinding wheel according to claim 1, characterized in that, Each of the cones (4) has a shallow circular groove (9) coaxially formed at its small end.

4. A diamond grinding wheel according to claim 1, characterized in that, Both the large end of the conical section and the large end of the conical body (4) are provided with a straight cylindrical section. During the axial movement of the conical body (4), the outer wall of the straight cylindrical section of the conical body (4) and the inner wall of the straight cylindrical section of the conical section are always in a close and sealed state.

5. A diamond grinding wheel according to claim 1 or 4, characterized in that, The outer ring body (3) has multiple axial grooves (10) evenly distributed on each end face, and the cone body (4) has multiple axial blocks (11) evenly distributed on the side wall of the large end face, with each axial block (11) being embedded in the axial groove (10) in a corresponding manner.

6. A diamond grinding wheel according to claim 1, characterized in that, The outer wall of the outer ring body (3) is parallel to the inner wall.

7. A diamond grinding wheel according to claim 1 or 6, characterized in that, The outer ring body (3) has several raised strips (12) that are parallel to the generatrix evenly distributed on its outer wall.

8. A cold pressing forming apparatus for grinding wheels, characterized in that, The grinding wheel is a diamond grinding wheel as described in any one of claims 1 to 7, comprising an upper die (13) and a lower die (14). The lower die (14) is a cylindrical shape with an open upper end. A first stepped groove (15) is coaxially opened on the inner bottom surface of the lower die (14). A second stepped groove (16) is coaxially opened on the bottom surface of the first stepped groove (15). A first rubber pad (17) is installed in the second stepped groove (16). A water inlet pipe (18) is installed at the axis of the lower die (14). The water inlet pipe (18) penetrates the bottom surface of the lower die (14) and the first rubber pad (17). The upper mold (13) is a circular flat plate. The outer diameter of the upper mold (13) is the same as the inner diameter of the lower mold (14). The lower surface of the upper mold (13) has a third stepped groove (19) coaxially. The bottom surface of the third stepped groove (19) has a fourth stepped groove (20) coaxially. The fourth stepped groove (20) contains a second rubber pad (21). A water outlet pipe (22) is installed at the axis of the upper mold (13). The water outlet pipe (22) passes through the upper mold (13) and the second rubber pad (21). A pressure valve (23) is installed on the water outlet pipe (22). A hydraulic cylinder (24) is provided on the top of the upper mold (13).

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