Uniform hole straight-through type inner cooling forming reamer

Abstract

A uniform through-hole type internal cooling forming reamer includes: a forming reamer, several cooling inlet holes at the rear end of the forming reamer, several cooling outlet holes at the front end of the forming reamer, and several through holes parallel to and connected to the center line of the tool body, where the cooling inlet and outlet holes are located between the cooling inlet and outlet holes; wherein, the forming reamer body is cylindrical; and at its front is a forming reamer with several inwardly recessed straight chip removal grooves. In the machining cooling process, the cooling outlet pressure and inlet pressure of each cutting edge are equal, ensuring that the cooling flow rate of each cooling hole does not decrease and the cooling effect is better; moreover, the sprayed cutting fluid can cover the entire cutting edge, and the cooling hole positions are more reasonable and scientific; at the same time, the cooling effect is more thorough and uniform, and the overall tool life can be increased by more than 50%, with no change in cooling effect when the reamer is regrinded and used.

Description

Technical Field

[0001] This utility model belongs to the field of mechanical manufacturing, and in particular relates to a uniform hole straight-through internal cooling forming reamer. Background Technology

[0002] Currently, in the intermediate housing products of turbocharger housings, there is a type of irregularly shaped forming hole with a forming reamer. The intersection of the diameter and end face of the forming hole is generally formed by one or more tangentially connected arc segments. High requirements are placed on both the diameter and surface roughness. It is generally machined using a solid carbide forming reamer, and the forming reamer must be designed to be exactly the same shape as the forming hole in the intermediate housing of the turbocharger housing.

[0003] A reamer is a cutting tool used for finishing holes. It is mainly used to perform subsequent finishing on drilled holes to improve the dimensional accuracy, shape accuracy and surface finish of the holes.

[0004] Currently, such as Figure 1 As shown, the internal cooling method is as follows: the shank of the forming reamer has a central hole, and at the cutting head position, i.e., above each cutting edge, a small hole is drilled and connected to the central hole. This drilling is done using electrical discharge machining (EDM). In this way, internal cooling water enters through the central hole in the shank and flows through the small holes at the cutting head position to each cutting edge. Its shape resembles a "tree branch".

[0005] In the current market, traditional straight-flush chip flute internally cooled alloy forming reamers are all in a "branch" form, i.e., a center-hole cooling method. Because there is a main cooling hole at the center of the tool, it disperses into multiple sub-cooling holes at the cutting edge, thus dispersing the pressure and flow rate of the cutting fluid. Therefore, ultimately, the pressure and flow rate of the ejected cutting fluid decrease, significantly impacting machining quality and tool life. Furthermore, the location where the cutting fluid is ejected is relatively fixed (generally mostly at the tip of the cutting edge), failing to cover the entire cutting edge, greatly reducing the cooling effect; i.e., flow rate reduction affects cooling efficiency. Finally, when the reamer is resharpened and reused, its cutting edge position shifts backward. With each resharpening cycle, the cutting fluid eventually fails to reach the cutting edge; i.e., the cutting fluid cannot completely cover the cutting edge. Utility Model Content

[0006] The purpose of this invention is to provide a uniform-hole straight-through internal cooling forming reamer to solve the technical problem that the pressure and flow rate attenuation during the injection of cutting fluid in traditional center-hole internal cooling reamers affects the cooling effect; and that when the forming reamer is reground and reused, its cutting edge position will shift backward, and the cutting fluid cannot completely cover the cutting edge.

[0007] To achieve the above objectives, the specific technical solution of the uniform hole straight-through internal cooling forming reamer of this utility model is as follows:

[0008] A uniform through-hole type internal cooling forming reamer includes: a forming reamer, several cooling liquid inlets disposed at the rear end of the forming reamer, several cooling liquid outlets disposed at the front end of the forming reamer, and several through-holes between the cooling liquid inlets and outlets being parallel to and interconnected with the center line of the reamer body; wherein, the forming reamer body is cylindrical; and at its front is a forming reamer with several inwardly recessed straight chip removal grooves.

[0009] Furthermore, the forming reamer is a straight chip flute type; depending on the diameter of the irregular hole to be processed, the commonly used selection is 4-9 teeth as the best, and the position of the internal cooling hole should be 1mm-2mm directly above the cutting edge.

[0010] Furthermore, the forming reamer is made of cemented carbide bar stock and is directly pressed into shape.

[0011] Furthermore, there are several cooling inlet holes; the size of the cooling inlet hole is 1.5mm in diameter, that is: diameter: 1.5mm; it is located on the edge of the end face of the tool holder clamping end, and each cutting edge corresponds to one cooling inlet hole.

[0012] Furthermore, the cooling outlet hole is provided in several places, and the size of the cooling outlet hole is the same as that of the inlet hole, that is, the diameter is 1.5mm. It is located in front of the cutting edge and opposite to the cooling inlet hole. The cutting fluid is sprayed out from this hole to cover the cutting edge and play a protective role such as cooling and lubrication.

[0013] Furthermore, the size of the through hole is the same as that of the cooling inlet and outlet holes, both being 1.5mm; that is, the diameter is 1.5mm; the through hole is made to a length of 330mm during bar stock pressing; when making the cutting tool, the material will be cut into sections between 80mm and 160mm depending on the actual working conditions; a tubular object is also connected to the through hole; the diameter of this tubular object is also 1.5mm.

[0014] Furthermore, the through hole is connected to the cooling outlet hole, the through hole is parallel to the center line of the reamer, and the channel diameter of the through hole is the same as the size of the cooling inlet hole and the cooling outlet hole; all cooling inlets are on the same cooling inlet hole diameter; the cutting fluid enters the cutting body of the forming reamer from the cooling inlet hole.

[0015] Furthermore, the cooling inlet and outlet holes are located at a distance A from the cutting edge tip face. Through simulation and experimentation, it was found that when the outer diameter of the cooling outlet hole is 1mm-2mm away from the cutting edge tip face, the cooling effect is optimal, the cutting fluid coverage is most comprehensive, and the protection of the tool cutting edge is best.

[0016] Furthermore, regarding the cooling inlet and outlet holes, the diameter of the cooling inlet hole should be less than or equal to the diameter of the cutting edge at the front of the tool to achieve better cooling. Generally, the optimal value is 0 ≤ cutting edge diameter - cooling inlet hole diameter ≤ 3mm. The cooling outlet hole is located directly above the cutting edge, and its position has a significant impact on the cooling effect. There is a certain positional relationship between the diameter of the cooling outlet hole and the diameter of the cutting edge at the front of the tool. When the cutting fluid is sprayed from this position, it can cover the entire cutting edge, resulting in excellent cooling and increasing the tool life by more than 50%.

[0017] The present invention, a uniform-hole straight-through internal cooling forming reamer, has the following advantages:

[0018] The cemented carbide bar used in this invention has cooling holes directly pressed out during the bar pressing process. The number of cooling holes varies depending on the diameter, generally ranging from 4 to 9 (for example, 4 cooling holes for D8.3 bar and 9 cooling holes for D20.3 bar). This has two additional advantages compared to the bar used in traditional solid cemented carbide forming reamers:

[0019] 1. Traditional alloy bars do not have pre-drilled cooling holes, while the cemented carbide bars used in this invention have cooling holes directly pressed into shape, which can save raw materials at the location of the cooling holes.

[0020] 2. Lower cost and higher efficiency: Traditional forming reamers require EDM to align the cooling hole at the tip, which is time-consuming and inefficient. However, the cemented carbide bar used in this invention does not require EDM drilling during the tool manufacturing process (the through hole during bar manufacturing is the final internal cooling hole), resulting in shorter tool manufacturing time, higher efficiency, and greater environmental friendliness.

[0021] In the machining and cooling process, the cooling pressure at the outlet and inlet of each cutting edge is equal, which not only ensures that the flow rate of each cooling hole does not decrease and the cooling effect is better, but also, from a fluid dynamics perspective, the sprayed cutting fluid can cover the entire cutting edge, and the position of the cooling holes is more reasonable and scientific. At the same time, the cooling effect is more thorough and uniform, and the overall tool life can be increased by more than 50%. The cooling effect remains unchanged when the reamer is reflashed and used. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the existing structure;

[0023] Figure 2 This is a three-dimensional structural diagram of the present invention;

[0024] Figure 3 This is a left-view stereoscopic structural diagram of the present invention;

[0025] Figure 4 This is a schematic diagram of the upper and lower equal angles of this utility model;

[0026] Figure 5 These are the upper and lower isogonal structural diagrams of this utility model;

[0027] Explanation of markings in the diagram:

[0028] 0. Forming reamer; 1. Cooling inlet hole; 2. Cooling outlet hole; 3. Through hole; A. Distance between cooling hole and cutting edge front face; B. Diameter of cooling inlet hole; C. Diameter of cutting edge at the tool front. Detailed Implementation

[0029] To better understand the purpose, structure, and function of this utility model, the following description, in conjunction with the accompanying drawings, provides a more detailed account of a uniform-hole straight-through internal cooling forming reamer.

[0030] like Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, this utility model includes: a straight chip groove forming reamer 0.

[0031] Several cooling inlet holes 1 (six in this embodiment) are located at the rear end of the forming reamer 0, on the end face of the tool holder clamping end, through which cutting fluid enters the tool body; several cooling outlet holes 2 are located at the front end of the forming reamer 0, and six through holes 3 (six in this embodiment) are located between the cooling inlet holes 1 and the cooling outlet holes 2; these are located directly in front of the cutting edge, through which cutting fluid is sprayed out, covering the cutting edge and providing cooling, lubrication, and other protective functions.

[0032] like Figure 2 As shown, the forming reamer 0 (in this embodiment, it is cylindrical) has several inwardly recessed straight chip grooves in front of it (in this embodiment, it is a 6-tooth reamer).

[0033] The forming reamer 0 is a straight chip flute type; depending on the diameter of the irregular hole to be machined, it is generally designed with 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 teeth. The commonly used choice is 4-9 teeth, which is the best. The position of the internal cooling hole should be 1mm-2mm directly above the cutting edge.

[0034] The aforementioned forming reamer 0 is made of cemented carbide bar stock and is directly pressed into shape. Several cooling inlet holes 1 (in this embodiment, there are 6, each 1.5mm in diameter) are located on the edge of the end face of the tool holder. Each cutting edge corresponds to one cooling inlet hole 1. A through hole 3 connects to a cooling outlet hole 2. The through hole 3 is parallel to the reamer's centerline, and its diameter is the same as that of the cooling inlet hole 1 and the cooling outlet hole 2. A tubular structure with a diameter of 1.5mm is also connected to the through hole 3. All cooling inlet holes 1 are located on the same cooling inlet hole diameter B. Cutting fluid enters the body of the forming reamer 0 from the cooling inlet holes 1.

[0035] There are several cooling outlet holes 2 (the size of the cooling outlet holes 2 is the same as that of the inlet 1, both are 1.5mm). They are located in front of the cutting edge and opposite to the cooling inlet hole 1. The cutting fluid is sprayed out from this hole, covering the cutting edge and playing a protective role such as cooling and lubrication.

[0036] The through hole 3 is the same size as the cooling inlet hole 1 and the cooling outlet hole 2, both being 1.5mm (i.e., the diameter is 1.5mm). The hole is directly die-cast during the bar stock pressing process; therefore, the length of the hole is the same as the length of the bar stock. During bar stock pressing, the length is made to be 330mm. When making the cutting tool, the material will be cut into sections between 80mm and 160mm depending on the actual working conditions. A tubular object is also connected to the through hole 3; the diameter of this tubular object is also 1.5mm.

[0037] like Figure 3 As shown, the diameter of the hole from the inlet to the outlet remains constant. In this case, a D18 shank reamer is used, which has 6 holes, each with a diameter of 1.5 mm.

[0038] The aforementioned cooling outlet 2 is located directly above the cutting edge, and its position has a significant impact on the cooling effect. The diameter of the cutting edge where the cooling outlet 2 is located is less than or equal to the diameter C of the cutting edge at the tool tip. Cooling fluid sprayed from this position can cover the entire cutting edge, resulting in excellent cooling and increasing tool life by more than 50%.

[0039] To improve the cooling effect, the cooling inlet hole 1 and cooling outlet hole 2 are located at a distance A from the cutting edge tip face. Through simulation and experimentation, it was found that when the outer diameter of the cooling inlet hole 1 and cooling outlet hole 2 is 1mm-2mm away from the cutting edge tip face, the cooling effect is the best, the cutting fluid coverage is the most comprehensive, and the protection of the tool cutting edge is also the best.

[0040] To achieve better cooling, the diameter of the cooling inlet hole B should be less than or equal to the diameter of the cutting edge C at the front of the tool. Through simulation and experimentation, empirical values ​​for CB have been found to be: -0.3 mm, -0.2 mm, -0.1 mm, 0 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, and 6 mm. Generally, the optimal empirical value is 0 ≤ CB ≤ 3 mm.

[0041] In use, the cooling inlet hole 1 of the forming reamer 0 of this utility model is located on the end face of the tool holder clamping end. Each cutting edge corresponds to one cooling inlet hole 1. There is a through hole 3 connected to the cooling outlet hole 2 through a tubular object (in this embodiment, a direct connection is used). The diameter of the through hole 3 is the same as the size of the cooling inlet hole 1 and the cooling outlet hole 2. All cooling inlets 1 are located on the same cooling inlet hole diameter B. This allows the forming reamer 0 to process the forming hole positions in the intermediate shell product of the turbine housing turbocharger.

[0042] The above-mentioned forming reamer is existing technology. Any technology not described is existing technology and will not be elaborated further.

[0043] It is understood that this utility model has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this utility model. Furthermore, under the teachings of this utility model, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of this utility model.

Claims

1. A uniform-hole straight-through internal cooling forming reamer, characterized in that, include: The forming reamer has several cooling inlets at its rear end and several cooling outlets at its front end. The cooling inlets and outlets between the forming reamer are several through holes parallel to the center line of the reamer body and interconnected. The forming reamer body is cylindrical, and in front of it are several inwardly recessed straight chip removal grooves.

2. The uniform-hole straight-through internal cooling forming reamer according to claim 1, characterized in that, The forming reamer is a straight chip flute type, and the internal cooling hole is located 1mm-2mm directly above the cutting edge.

3. The uniform-hole straight-through internal cooling forming reamer according to claim 1 or 2, characterized in that, The forming reamer is made of cemented carbide bar stock and is directly pressed into shape.

4. The uniform-hole straight-through internal cooling forming reamer according to claim 1, characterized in that, The cooling inlet hole is provided in several parts; the size of the cooling inlet hole is 1.5mm in diameter; it is located on the edge of the end face of the tool holder clamping end, and each cutting edge corresponds to one cooling inlet hole.

5. The uniform-hole straight-through internal cooling forming reamer according to claim 1, characterized in that, The cooling outlet hole is provided in several places. The size of the cooling outlet hole is the same as that of the inlet hole, that is, the diameter is 1.5mm. It is located in front of the cutting edge and opposite to the cooling inlet hole. The cutting fluid is sprayed out from this hole and covers the cutting edge.

6. The uniform-hole straight-through internal cooling forming reamer according to claim 1, characterized in that, The size of the through hole is the same as that of the cooling inlet and outlet holes, both being 1.5mm. When pressing the bar stock, the through hole is made to a length of 330mm. When making the cutting tool, the material will be cut into sections between 80mm and 160mm depending on the actual working conditions. A tubular object is also connected to the through hole, and the diameter of the tubular object is also 1.5mm.

7. The uniform-hole straight-through internal cooling forming reamer according to claim 1, 4, 5 or 6, characterized in that, The through hole is connected to the coolant outlet hole and is parallel to the center line of the reamer. The diameter of the through hole is the same as the size of the coolant inlet hole and the coolant outlet hole. All coolant inlets are on the same coolant inlet diameter. The cutting fluid enters the body of the forming reamer from the coolant inlet hole.

8. The uniform-hole straight-through internal cooling forming reamer according to claim 1, 4 or 5, characterized in that, The cooling inlet and outlet holes are located at a distance A from the cutting edge tip face. When the distance A between the outer diameter of the cooling outlet hole and the cutting edge tip face is 1mm-2mm, the cutting edge of the tool is protected.

9. The uniform-hole straight-through internal cooling forming reamer according to claim 1, 4, or 5, characterized in that, The cooling inlet and cooling outlet are related as follows: the diameter of the cooling inlet is less than or equal to the diameter of the cutting edge at the front of the tool; the cooling outlet is located directly above the cutting edge.

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