Assembly type center hole grinding center
By using a center hole grinding tip with an assembled structure, the problem of low utilization rate of cemented carbide and diamond grinding wheels is solved, realizing efficient utilization of cemented carbide materials and cost reduction, and extending the service life of the grinding tip.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-21
- Publication Date
- 2026-03-13
AI Technical Summary
The existing technology has low utilization rates of embedded carbide tool holders and diamond grinding wheels, resulting in resource waste and increased production costs.
The center hole grinding tip adopts an assembled structure, including a carbide rod, a pressure cap, a tool body, and an adjusting screw. The carbide rod can be detached and adjusted through threaded connection and ER expansion sleeve, which extends its service life and improves material utilization.
It increases the utilization rate of cemented carbide rods by 5 times, reduces tool costs, extends the service life of grinding tips, and reduces the consumption of diamond grinding wheels and environmental pollution.
Smart Images
Figure CN223989377U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of grinding technology for shaft parts, and in particular, it is an assembled center hole grinding tip. Background Technology
[0002] In order to effectively address the deformation problems that may occur during the heat treatment process and further improve the roundness of the center hole and significantly reduce its surface roughness, the industry generally adopts the method of grinding the center hole with cemented carbide to ensure the final quality of shaft parts after heat treatment and before grinding.
[0003] Currently, the main type used is the integrated center hole grinding tip, with a structure as follows: Figure 1 As shown, the tool holder uses a Morse taper fit, while the cutting tip is made of cemented carbide and tightly bonded to the tool holder using welding technology. Only a small portion of the cemented carbide is actually used in the grinding process, which limits the full utilization of the material; the utilization rate of the cemented carbide embedded in the tool holder is only 50%. When this type of grinding tip tool reaches its service life limit, because the cemented carbide and tool holder are welded together as a single unit, the entire tool, including the cemented carbide embedded in the tool holder and the tool holder itself, which still has potential use value, is scrapped and discarded, resulting in a significant waste of resources.
[0004] Meanwhile, in traditional center-hole grinding tips, the carbide portion is welded to the tool shank using an octagonal or hexagonal pyramid with a 60° angle. After the carbide cutting edge becomes dull, it can be repeatedly used by sharpening with a diamond wheel. However, during sharpening, the diamond wheel inevitably grinds the iron shank while simultaneously grinding the carbide cutting edge. Due to the relatively poor thermal stability of diamond, when the grinding temperature exceeds 600-700℃, the carbon atoms in the diamond easily diffuse into the iron group metals of the tool shank, forming carbides and causing chemical wear of the diamond wheel. A single diamond wheel can typically only grind about 40 such center-hole grinding tips before needing to be replaced, further increasing production costs. Therefore, how to improve the utilization rate of carbide materials and extend the service life of diamond wheels while ensuring grinding quality has become a pressing technical challenge in the current machining of shaft parts. Summary of the Invention
[0005] The purpose of this invention is to provide an assembled center hole grinding tip to solve the problem of low utilization rate of embedded carbide and diamond grinding wheels in the prior art.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] An assembled center hole grinding tip includes a carbide rod, a pressure cap, a tool body, and an adjusting screw.
[0008] The pressure cap is fixedly connected to the cutter body. Both the pressure cap and the cutter body have through holes along the axial direction. One end of the cemented carbide rod passes through the pressure cap and is inserted into one end of the through hole in the cutter body. The adjusting screw is assembled at the other end of the through hole in the cutter body.
[0009] Furthermore, the other end of the cemented carbide rod is a pointed tip, which is a hexagonal pyramid or an octagonal pyramid structure, and the included angle of the pyramidal edges of the pointed tip is 60°.
[0010] Furthermore, the tip of the cemented carbide rod is 20-30 mm higher than the gland.
[0011] Furthermore, the pressure cap has an internal thread in its through hole, and one end of the blade has an external thread. The internal thread of the pressure cap and the external thread of the blade are engaged and fixedly connected.
[0012] Furthermore, an ER expansion sleeve is provided between the pressure cap and the blade body for clamping and fixing the cemented carbide rod.
[0013] Furthermore, the ER expansion sleeve has an inner hole through which the cemented carbide rod passes.
[0014] Furthermore, the cutter body is provided with a Morse taper, and the cutter body is mounted on the center hole grinding machine through the Morse taper.
[0015] Furthermore, the through hole inside the cutter body is provided with an internal thread, and the adjusting screw is provided with an external thread, with the internal thread of the cutter body engaging with the external thread of the adjusting screw.
[0016] Furthermore, one end of the adjusting screw is pressed against the end of the carbide rod inserted into the through hole inside the cutter body.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] This invention provides an assembled center-hole grinding tip. By fixing the pressure cap to the tool body, the stability of the structure and the rigidity required during grinding are ensured. Through holes are opened axially in both the pressure cap and the tool body. One end of a carbide rod is inserted through the pressure cap into one end of the through hole in the tool body. The hollow tool body holds the carbide rod, and an adjusting screw is assembled at the other end of the through hole in the tool body, making the carbide rod movable and replaceable. When the carbide rod is worn or damaged, it can be easily removed and replaced with a new one, thus extending the service life of the entire grinding tip. Furthermore, by rotating the adjusting screw, the extension and retraction length of the carbide rod can be precisely adjusted, thereby better withstanding the axial force during grinding. This invention changes the structure from a welded structure to an assembled structure. Carbide rods of appropriate diameter can be selected and installed according to the size of the center hole of the workpiece. Besides repeated use and sharpening, only the carbide rod material is consumed; the rest can be reused, without being scrapped or discarded, making it more economical and convenient. Compared to traditional integral grinding tips, the utilization rate of carbide rods is increased by 5 times, and the sharpening efficiency is doubled. The tool cost per center hole grinding is reduced from 0.045 yuan to 0.005 yuan. The tool body can be reused, saving 400 scrapped tool bodies annually and reducing waste caused by discarding center hole grinding tool bodies. Secondly, during sharpening, the diamond wheel only grinds the carbide rod, eliminating contact between the diamond wheel and the iron shank and completely avoiding chemical wear of the diamond wheel. The reduced grinding contact area saves on diamond wheel consumption. Compared to traditional center hole grinding tips, diamond wheel consumption is reduced by 70%, saving sharpening costs and further reducing tool costs. Attached Figure Description
[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a physical image of the traditional center hole grinding tip of this utility model.
[0021] Figure 2 This is a schematic diagram of the assembled center hole grinding tip structure of this utility model.
[0022] Figure 3 This is a physical image of the assembled center hole grinding tip of this utility model.
[0023] Among them: 1-carbide rod, 2-pressure cap, 3-ER expansion sleeve, 4-cutting body, 5-adjusting screw. Detailed Implementation
[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0027] In the description of the embodiments of this utility model, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use, they are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the utility model. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0028] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0029] In the description of the embodiments of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0030] The present invention will now be described in further detail with reference to the accompanying drawings:
[0031] See Figure 2 and Figure 3 This utility model provides an assembled center hole grinding tip, including a carbide rod 1, a pressure cap 2, an ER expansion sleeve 3, a tool body 4, and an adjusting screw 5.
[0032] Both the pressure cap 2 and the cutter body 4 have through holes along the axial direction. The pressure cap 2 has an internal thread in its through hole, and one end of the cutter body 4 has an external thread. The internal thread of the pressure cap 2 mates with the external thread of the cutter body 4, achieving a tight and stable threaded connection. This facilitates adjusting the position of the carbide rod or replacing it with a different specification of carbide rod 1 as needed. One end of the carbide rod 1 passes through the pressure cap 2 and is inserted into one end of the through hole in the cutter body 4. The other end of the carbide rod 1 is a pointed tip, which protrudes 20-30mm higher than the pressure cap 2. The tip is ground into a hexagonal or octagonal pyramid structure using a diamond grinding wheel, with a 60° included angle between the pyramidal edges, providing optimal cutting performance and durability during grinding. The cutter body 4 has a Morse taper for mating with the taper hole of a center hole grinder. The cutter body 4 is mounted on the center hole grinder via the Morse taper, ensuring compatibility with the grinder and ease of installation and disassembly. When the center hole grinding machine is started and rotates, the conical edge at the tip of the carbide rod 1 contacts the center hole to be ground, thus grinding the center hole.
[0033] An ER expansion sleeve 3 is provided between the pressure cap 2 and the tool body 4. The ER expansion sleeve 3 has an inner hole through which the carbide rod 1 passes. When the inner hole is subjected to external force, it will elastically contract, thereby tightly clamping the carbide rod 1 inserted therein. The outer surface of the ER expansion sleeve 3 is designed with a structure that mates with the pressure cap 2 and the tool body 4. The internal thread of the pressure cap 2 is screwed tightly with the external thread of the tool body 4, applying pressure to the ER expansion sleeve 3, causing the inner hole of the ER expansion sleeve 3 to elastically contract, thereby clamping and fixing the carbide rod 1, preventing it from shaking or falling off during the grinding process, thus ensuring the accuracy and safety of the grinding.
[0034] The adjusting screw 5 is fitted to the other end of the through hole inside the cutter body 4. The through hole inside the cutter body 4 has an internal thread, and the adjusting screw 5 has an external thread. The internal thread of the cutter body 4 mates with the external thread of the adjusting screw 5. One end of the adjusting screw 5 is pressed against the end of the carbide rod 1 inserted into the through hole inside the cutter body 4. The threaded connection not only achieves a stable connection between the adjusting screw 5 and the cutter body 4, but also allows for convenient, quick, and precise adjustment of the extension length of the carbide rod 1 by tightening and loosening the thread. The extension length of the carbide rod 1 can be gradually increased or decreased as needed to optimize its stress state during the grinding process, thereby better withstanding the axial force during grinding, adapting to different grinding requirements, and greatly enhancing the adaptability and flexibility of the grinding tip.
[0035] By selecting an ER expansion sleeve 3 with a diameter corresponding to that of the carbide rod 1, inserting the carbide rod 1 into the ER expansion sleeve 3, and placing it into the through hole of the tool body 4, screwing on the pressure cap 2 to adjust the tip of the carbide rod 1 to be 20~30mm higher than the pressure cap 2, tightening the pressure cap 2, and screwing the adjusting screw 5 into the other end of the through hole inside the tool body 4 until the carbide rod 1 is on top. The assembly-type center hole grinding tip is now installed.
[0036] The newly installed assembly-type center hole grinding tip is first sharpened using a diamond grinding wheel to create a pyramidal cutting edge, ensuring a sharp and accurate tip. After sharpening, it is ready to use on a center hole grinding machine. During use, after grinding a certain number of center holes, the pyramidal edge of the carbide rod 1 gradually wears and dulls. The assembly-type center hole grinding tip is then removed and further sharpened to restore its grinding performance. After repeated use and sharpening, the carbide rod 1 becomes shorter. When the diamond grinding wheel is about to wear down the pressure cap 2, to prevent the diamond grinding wheel from wearing down the pressure cap 2, the pressure cap 2 is loosened by rotating it. The adjusting screw 5 is then rotated to push the carbide rod 1 to a suitable length. The pressure cap 2 is then tightened, and the rod is reused repeatedly to extend its service life. This continues until the carbide rod 1 is used to a length shorter than the minimum clamping length, at which point it is replaced with a new carbide rod 1. Alternatively, a carbide rod 1 of the appropriate diameter can be selected based on the size of the center hole of the workpiece, further reducing tool costs.
[0037] This utility model's assembled center hole grinding tip, besides being repeatedly used and sharpened, only consumes the carbide rod 1 as the cutting tip material; the rest can be reused without being scrapped or discarded, avoiding the high costs associated with frequently replacing the entire grinding tip. Simultaneously, during sharpening, the diamond wheel only grinds down to the carbide rod 1, completely eliminating chemical wear on the diamond, saving on diamond wheel usage and reducing environmental pollution.
[0038] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A modular center hole grinding center, characterized by, Including hard alloy rod (1), gland (2), cutter body (4) and adjusting screw rod (5); The gland (2) is fixedly connected with the cutter body (4), the through hole is formed in the gland (2) and the cutter body (4) along the axial direction, one end of the hard alloy rod (1) is inserted into one end of the through hole in the cutter body (4) through the gland (2), and the adjusting screw rod (5) is assembled in the other end of the through hole in the cutter body (4).
2. The assembled center hole lapping tip of claim 1, wherein, The other end of the hard alloy rod (1) is a pointed end, the pointed end is a hexagonal pyramid or an octagonal pyramid structure, and the included angle of the conical edge of the pointed end is 60°.
3. The assembled center hole lapping tip of claim 1, wherein, The pointed end of the hard alloy rod (1) is higher than the gland (2) by 20-30 mm.
4. The assembled center hole lapping tip of claim 1, wherein, The through hole of the gland (2) is provided with an internal thread, one end of the cutter body (4) is provided with an external thread, and the internal thread of the gland (2) is fixedly connected with the external thread of the cutter body (4) in a matched mode.
5. The assembled center hole lapping tip of claim 1, wherein, An ER expansion sleeve (3) is arranged between the gland (2) and the cutter body (4) and used for clamping and fixing the hard alloy rod (1).
6. The assembled center hole lapping tip of claim 5, wherein, An inner hole is formed in the ER expansion sleeve (3), and the hard alloy rod (1) passes through the inner hole.
7. The assembled center hole lapping tip of claim 1, wherein, The cutter body (4) is provided with a Morse taper, and the cutter body (4) is installed on a center hole grinding machine through the Morse taper.
8. The assembled center hole lapping tip of claim 1, wherein, The through hole in the cutter body (4) is provided with an internal thread, the adjusting screw rod (5) is provided with an external thread, and the internal thread of the cutter body (4) is matched with the external thread of the adjusting screw rod (5).
9. The assembled center hole lapping tip of claim 1, wherein, One end of the adjusting screw rod (5) is tightly pressed against the hard alloy rod (1) and inserted into one end of the through hole in the cutter body (4).