CN104607722A - High precision forming reamer - Google Patents

Abstract

The invention provides a high precision forming reamer. The high precision forming reamer comprises a cutter body and a cutter head formed at one end of the cutter body. A first cutting edge is formed at the end of the cutter head, the first cutting edge is of an RC type, and a plurality of reaming parts are further formed on the cutter head. The cutter head is further provided with four chip removal grooves, the axial cross section of the cutter head is in a crossed shape, and the four chip removal grooves extend to the other end of the cutter head from one end of the cutter head. A second cutting edge of the cutter head is formed on the edge of each chip removal groove, and the second cutting edges are formed on the side face of the cutter head. The positive cone of the core thickness of the cutter head is 0.8:10 or 1.2:10. Forming faces of the cutter head are formed on the wall face, making contact with the hole walls of machined step holes, of the cutter head. The high precision forming reamer meets the requirements that materials used for machining hydraulic valve body holes are machined difficultly, the number of steps is large and the service life is long. Reamers of various structures are combined with the corresponding forming faces, the corresponding step holes can be machined and formed at a time, and the machining efficiency and the machining precision are high.

Description

High Precision Forming Reamer

technical field

The invention relates to the technical field of precision cutting tools, in particular to a high-precision forming reamer.

Background technique

The hydraulic valve block is the core component of construction machinery. When processing the assembly hole of the valve block, the size and structure of the hole are complicated, with many related dimensions and high precision. The surface of the hole and the forming surface is required to be above Ra0.8. Existing reamers are usually difficult to meet the requirements when machining assembly holes.

As shown in FIG. 1 , it is a schematic plan view of an existing reamer. When using the existing reamer to process the above-mentioned workpiece, the processing is difficult to meet the requirements. This is because, during processing, for multi-step holes and surfaces, it needs to be divided into multiple reamers for processing. For example, the installation hole of the valve block is composed of a three-step hole and a forming surface. The existing process is processed by three general-purpose reamers and one forming tool. In this way, the processing efficiency is low and the processing cost is high. Moreover, after the three stepped holes are processed separately, the relevant precision cannot meet the requirements. The normal requirement is that the coaxiality is 0.01MM, but the actual processing is 0.02-0.04MM. In addition, the related dimensions of the forming surface that lead to subsequent processing cannot be accurately controlled.

Therefore, in order to solve the above problems, it is necessary to propose further solutions.

Contents of the invention

The object of the present invention is to provide a high-precision forming reamer to overcome the deficiencies in the prior art.

In order to achieve the above object, the present invention provides a high-precision forming reamer, which includes: a cutter body and a cutter head formed at one end of the cutter body;

The end of the cutter head is formed with a first cutting edge, the first cutting edge is RC type, and a number of reaming parts are formed on the cutter head, among the adjacent reaming parts, the the diameter of the reamed portion of the first cutting edge is greater than the diameter of the reamed portion proximate said first cutting edge;

Four chip removal grooves are also provided on the cutter head, the axial cross-sectional shape of the cutter head is cross-shaped, and the four chip removal grooves extend from one end of the cutter head to the other end, any of the chip removal grooves The edge of the groove forms the second cutting edge of the cutter head, and the second cutting edge is formed on the side of the cutter head; the core thickness of the cutter head is 0.8:10 or 1.2:10;

The wall surface of the cutter head in contact with the hole wall of the stepped hole formed by processing forms the forming surface of the cutter head.

As an improvement of the high-precision forming reamer of the present invention, when the ratio of the length and diameter of the cutter head is less than or equal to 2.5:1, the core thickness of the cutter head is 0.8:10; the length of the cutter head and When the diameter ratio is greater than or equal to 2.5:1, the core thickness of the cutter head is 1.2:10.

As an improvement of the high-precision forming reamer of the present invention, the transition connection between the first cutting edge and the second cutting edge is made through a fillet and chamfer structure.

As an improvement of the high-precision forming reamer of the present invention, the cutting angle of the cutter head is 55-65°; the relief angle is 7-9°.

As an improvement of the high-precision forming reamer of the present invention, the material of the high-precision forming reamer is cemented carbide, and its model is ISO05-10 or ISO30-40.

As an improvement to the high-precision forming reamer of the present invention, the forming surfaces corresponding to the four second cutting edges are planes.

Compared with the prior art, the beneficial effect of the present invention is that the high-precision forming reamer of the present invention satisfies the requirements of difficult machining, many steps and long service life for machining hydraulic valve body holes. It combines a variety of structural reamers with the corresponding forming surface, and can process the corresponding stepped hole at the forming position at one time, with high processing efficiency and processing accuracy.

Description of drawings

Fig. 1 is the schematic plan view of existing reamer;

Fig. 2 is a schematic plan view of a specific embodiment of the high-precision forming reamer of the present invention;

Fig. 3 is a side view of the high-precision forming reamer in Fig. 2 .

Detailed ways

The present invention is described in further detail now in conjunction with accompanying drawing. These drawings are all simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, so they only show the configurations related to the present invention.

Changes and modifications shown in Figures 2 and 3. The technical scope of the present invention is not limited to the content in the specification, but must be determined according to the scope of the claims.

As shown in FIGS. 2 and 3 , the high-precision forming reamer 100 of the present invention includes: a cutter body 10 and a cutter head 20 formed at one end of the cutter body. Wherein, during the design process of the cutter head, the main deflection angle is reduced to improve the guideability of the cutter, and the friction between the flank and the workpiece is reduced by increasing the relief angle to improve the roughness of the machined surface. Specifically, the main deflection angle is 55-65°; the relief angle is 7-9°.

A first cutting edge 21 is formed at the end of the cutter head 20, and the first cutting edge 21 is RC-shaped. Such setting makes the cutting edge longer, the transition is smooth, and the cutting is lighter and faster.

Several reaming portions 22 are also formed on the cutter head 20 . The first cutting edge 21 cuts holes in the processed material, and the plurality of reaming portions 22 widen the size of the opened holes to form a trapezoidal hole structure. Among the adjacent reaming portions 22 , the diameter of the reaming portion 22 away from the first cutting edge 21 is larger than the diameter of the reaming portion 22 close to the first cutting edge 21 . Thus, several reaming portions 22 form a stepped structure. Further, the wall surface of the cutter head 20 in contact with the hole wall of the processed stepped hole forms the forming surface of the cutter head. Therefore, it combines a variety of structural reamers with corresponding forming surfaces, and can process the corresponding stepped holes at the forming position at one time, with high processing efficiency and processing accuracy.

The cutter head 20 is also provided with four flutes 23 , so that the axial cross-section of the cutter head 20 is cross-shaped. The four flutes 23 extend from one end of the cutter head 20 to the other end, and the edges of the flutes 23 form the second cutting edge 24 of the cutter head. The second cutting edge 24 is formed on the side of the cutter head 20 . The transition between the first cutting edge 21 and the second cutting edge 24 is connected by rounded corners and chamfering structures, so that the cutting is lighter and quicker, and at the same time, the strength of the cutting edge and the quality of the processed surface are guaranteed. In addition, the forming surfaces corresponding to the four second cutting edges 24 are flat, so that the cutting edge is finer, the strength of the cutting edge is further improved, and the processed surface is smoother.

The core thickness of the cutter head 20 is 0.8:10 or 1.2:10. When the ratio of the length to the diameter of the cutter head 20 is less than or equal to 2.5:1, the core thickness of the cutter head 20 is 0.8:10; when the ratio of the length to the diameter of the cutter head 20 is greater than or equal to 2.5:1 , the core thickness of the cutter head is 1.2:10. With such arrangement, each reaming portion of the high-precision forming reamer of the present invention has sufficient core thickness and strength, and a space for chip containment and chip removal.

When selecting materials for the high-precision forming reamer of the present invention, the material of the high-precision forming reamer is cemented carbide, and its model is ISO05-10 or ISO30-40. Specifically, the hardness, strength, and grain size of the material should be considered, among which, the hardness must be >HRV1850, and the tensile strength must be 3400N/mm ² . The bar grain size should not be greater than 0.3-0.5μm. In addition, since the Co content directly affects the wear resistance of the reamer, the Co content in the cemented carbide must be less than 6%.

When manufactured, it can be fabricated on a five-axis CNC tool grinder. Specifically, the front and rear cutter faces should be finely polished with a 1000-mesh ultra-fine grinding wheel. The diameter of the grinding wheel can be finely selected according to the diameter of the tool; the core thickness can be adjusted according to the ratio of the diameter of the step, and the specific values are as above; the tip of the tool is treated as The transition of arc and chamfer makes the cutting more light and fast, while ensuring the strength of the tool tip and the quality of the processed surface; the relief angle of the forming surface adopts four-plane relief angle, and the linear motion of the machine tool is used in manufacturing to ensure the fineness of the cutting edge of the forming surface.

Next, the performance of the high-precision forming reamer of the present invention is tested, specifically, the selected model is 45#, and the hardness is HB160-180 steel. By measuring the cutting speed, spindle speed, feed speed, processing quantity, cutting efficiency, processing accuracy, surface quality, and dimensional accuracy during processing, the performance of the high-precision forming reamer of the present invention and the existing reamer is compared. The test results are shown in Table 1 below:

Table 1

It can be seen from Table 1 that the processing efficiency and cutting precision of the high-precision forming reamer of the present invention are significantly higher than those of the existing processing method using multiple reamers.

To sum up, the high-precision forming reamer of the present invention meets the requirements of difficult machining, many steps and long service life for machining hydraulic valve body holes. It combines a variety of structural reamers with the corresponding forming surface, and can process the corresponding stepped hole at the forming position at one time, with high processing efficiency and processing accuracy.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

In addition, it should be understood that although this specification is described according to implementation modes, not each implementation mode only contains an independent technical solution, and this description in the specification is only for clarity, and those skilled in the art should take the specification as a whole , the technical solutions in the various embodiments can also be properly combined to form other implementations that can be understood by those skilled in the art.

Claims (6)

1. A high-precision forming reamer, characterized in that, the high-precision forming reamer comprises: a cutter body, a cutter head formed at one end of the cutter body; The end of the cutter head is formed with a first cutting edge, the first cutting edge is RC type, and a number of reaming parts are formed on the cutter head, among the adjacent reaming parts, the the diameter of the reamed portion of the first cutting edge is greater than the diameter of the reamed portion proximate said first cutting edge; Four chip removal grooves are also provided on the cutter head, the axial cross-sectional shape of the cutter head is cross-shaped, and the four chip removal grooves extend from one end of the cutter head to the other end, any of the chip removal grooves The edge of the groove forms the second cutting edge of the cutter head, and the second cutting edge is formed on the side of the cutter head; the core thickness of the cutter head is 0.8:10 or 1.2:10; The wall surface of the cutter head in contact with the hole wall of the stepped hole formed by processing forms the forming surface of the cutter head. 2. The high-precision forming reamer according to claim 1, characterized in that, when the ratio of the length to diameter of the cutter head is less than or equal to 2.5:1, the core thickness of the cutter head is 0.8:10; When the ratio of the length to the diameter of the cutter head is greater than or equal to 2.5:1, the core thickness of the cutter head is 1.2:10. 3. The high-precision forming reamer according to claim 1, characterized in that, the transition connection between the first cutting edge and the second cutting edge is made through a fillet and chamfer structure. 4. The high-precision forming reamer according to claim 1, characterized in that, the entering angle of the cutter head is 55-65°; the relief angle is 7-9°. 5. The high-precision forming reamer according to claim 1, characterized in that, the material of the high-precision forming reamer is cemented carbide, and its model is ISO05-10 or ISO30-40. 6. The high-precision forming reamer according to claim 1, wherein the forming surfaces corresponding to the four second cutting edges are planes.