Automatic adjusting device for boring taper hole in machining center

Abstract

The machining center boring taper hole automatic adjusting device comprises a rack cutter handle arranged in a shell, the end, arranged in the shell, of the rack cutter handle is connected with a gear in a meshed mode, and the gear is connected with a rack cutter bar in a meshed mode in the vertical direction; the other end of the rack cutter handle is connected with a W shaft of a machine tool, the rack cutter bar moves up and down through front-back movement of the W shaft, the end face of the shell is connected with a machine tool spindle, and the spindle drives the shell to achieve rotation and front-back movement of the rack cutter bar on the shell. A machine tool W shaft moves back and forth to drive a rack cutter bar to achieve variable-diameter movement, a machine tool spindle moves back and forth to drive a boring cutter device to move back and forth, the machine tool spindle rotates to drive the boring cutter device to rotate, and therefore variable-diameter linear boring machining of the rack cutter bar is achieved. By changing the motion linear proportion of the rack cutter handle and the rack cutter bar, boring of deep holes with different tapers within a certain range can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical processing, and in particular relates to an automatic adjustment device for boring and taper holes in a machining center. Background Art

[0002] With the continuous development of hypersonic technology, the speed range and maneuverability requirements of spacecraft are constantly increasing, and they need to work stably in extreme environments. As one of the important power structure components of spacecraft, the separation rocket nozzle has extremely complex structural geometry and extremely high dimensional accuracy requirements. The existing processing technology can only achieve single-level cylindrical high-precision hole precision boring processing, which is extremely challenging for multi-level conical deep hole precision processing.

[0003] Existing technical solution: For multi-level, stepped tapered deep hole structures, high precision requirements are required, and boring milling cutters cannot be used for boring processing. At present, a four-axis horizontal machining center combined with an extended tool is generally used for line cutting. The extended tool is an extended end mill with a diameter of Φ20mm and a length of 380mm. The conical surface is processed in layers with a feed rate of 0.15mm until the entire conical deep hole is processed. The existing technology has the following disadvantages: (1) The end mill is used for line cutting, with a small feed rate and low processing efficiency; (2) The extended tool has poor rigidity, and it is easy to produce vibration marks or even overcutting on the side wall of the conical surface, resulting in the surface quality of the part being difficult to meet the design requirements; (3) The extended tool has poor rigidity, and there is a serious phenomenon of tool letting go during the cutting process. The taper of the conical deep hole does not meet the requirements and the processing accuracy is low; (4) Ordinary boring cutters on the market can only realize cylindrical hole boring processing, and cannot realize conical deep hole boring processing.

[0004] The Chinese invention patent with the publication number CN101362221B discloses a device and method for boring a taper hole for a CNC machine tool, which includes a taper shank, an inner gear ring, a planetary gear, a main gear and a tool bar. The device calculates the radial movement of the tool bar according to the rotation of the spindle, and then calculates the pitch value according to the taper to realize automatic boring of the taper hole. The internal structure is complex and the volume is large, which makes it difficult to realize small taper hole processing. In addition, since the machine tool cannot instantly reach the set value and the spindle speed is 0, it is difficult to ensure the accuracy during processing. The Chinese invention patent with the publication number CN116921720A discloses a taper boring tool with adjustable taper and a step hole processing method. The invention uses a transmission extension rod to support the bottom surface of the taper hole to adjust the boring tool overhang length, thereby realizing taper hole processing. This device is only suitable for blind hole taper hole processing, and cannot realize taper through hole processing. Moreover, the taper cannot be adjusted arbitrarily, and the application range is small. Summary of the invention

[0005] In order to solve the above problems, the present invention aims to provide an automatic adjustment device for boring and taper holes in a machining center.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme: an automatic adjustment device for boring and taper holes in a machining center, comprising a rack tool holder arranged in a housing, one end of the rack tool holder arranged in the housing is gear-connected with a gear, and a rack tool rod is gear-connected in the vertical direction of the gear;

[0007] The other end of the rack tool handle is connected to the W axis of the machine tool, and the rack tool bar is moved up and down by the forward and backward movement of the W axis. The end face of the shell is connected to the main shaft of the machine tool, and the main shaft drives the shell to realize the rotation and forward and backward movement of the rack tool bar on the shell.

[0008] Furthermore, the shell is formed by integrating a flange and a cylinder, the inner end of the flange is provided with a stepped hole formed by a square hole and a cylindrical hole, the inner side of the cylinder is provided with a circular hole and a depression, the top of the cylinder is provided with a square guide groove, and the other end of the cylinder is an open structure.

[0009] Furthermore, one end of the rack handle is a BT-type handle structure, and the other end is a rack structure, and a protrusion structure is also provided on the rack handle;

[0010] The raised structure of the rack tool handle is clamped in the square hole of the shell to achieve guiding and limiting.

[0011] Furthermore, a blade is installed at one end of the rack cutter bar, and the side surface of the cutter bar is a side rack structure. The rack cutter bar passes through the guide groove above the shell and is connected and matched with the internal gear.

[0012] Furthermore, the gear is a pair of gears connected by an inclined meshing connection, each gear is fixed by a gear shaft, and a sleeve is also provided on the gear for axial limiting. The gear obliquely arranged at the lower end meshes with the rack structure of the rack tool handle, and the gear obliquely arranged at the upper end meshes with the side rack structure of the rack tool rod.

[0013] Furthermore, the gear shaft is a stepped shaft with a keyway provided thereon for radially limiting the gear, and the sleeve is a cylindrical tubular structure for axially limiting the gear. One end of the gear shaft is also connected to a blocking cover, which is provided with a screw mounting hole for being connected and fixed to the outer shell, and its raised end is used to support the gear shaft.

[0014] Furthermore, a plurality of screw mounting through holes are provided on the end surface of the flange for being connected and fixed to the machine tool spindle, and the BT-type shank structure end of the rack shank is connected to the W-axis of the horizontal five-axis boring and milling machining center.

[0015] Furthermore, an end cover is provided at the opening structure of the cylinder on the outer shell.

[0016] Furthermore, the feed speed of the spindle moving forward and backward is F1, the feed speed of the W axis moving forward and backward is F2, and the ratio of F1 to F2 is equal to the taper of the tapered deep hole α.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. Through linear conversion, the present invention can complete the precision machining of multi-level and stepped conical deep holes in one time. The front and back movement of the W-axis of the machine tool drives the rack cutter bar to achieve variable diameter movement, the front and back movement of the main shaft of the machine tool drives the boring tool device to move back and forth, and the rotation of the main shaft of the machine tool drives the boring tool device to rotate, so as to realize the variable diameter linear boring machining of the rack cutter bar. At the same time, by changing the linear ratio of the movement of the rack tool handle and the rack cutter bar, the boring machining of deep holes with different tapers within a certain range can be realized. It has strong versatility.

[0019] 2. The present invention has a compact structure and good rigidity. When carrying out the boring machining of conical deep holes, it has the advantages of high machining accuracy, good surface quality, stable and reliable quality, and high machining efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 Schematic diagram of the boring conical hole automatic adjustment device in the machining center of the present invention;

[0022] Figure 2 Front view of the rack tool handle of the present invention;

[0023] Figure 3 Side view of the rack tool handle of the present invention;

[0024] Figure 4 Front view of the housing of the present invention;

[0025] Figure 5 Side view of the housing of the present invention;

[0026] Figure 6 Front view of the rack cutter bar of the present invention;

[0027] Figure 7 Schematic diagram of the end cover of the present invention;

[0028] Figure 8 Schematic diagram of the gear shaft of the present invention;

[0029] Figure 9 Front view of the sleeve of the present invention;

[0030] Figure 10 Side view of the sleeve of the present invention;

[0031] Figure 11 This is the front view of the plug cover in the present invention;

[0032] Figure 12 This is the side view of the plug cover in the present invention;

[0033] Figure 13 This is a schematic diagram of the conical deep hole structure on the side of the outer shape of a certain product;

[0034] In the figure, 1 is the rack tool shank; 11 is the BT-type tool shank structure; 12 is the rack structure; 13 is the convex structure; 2 is the housing; 21 is the flange; 22 is the cylinder; 23 is the guide rail groove; 3 is the key; 4 is the blade; 5 is the rack tool bar; 51 is the side rack structure; 6 is the gear shaft; 7 is the plug cover; 8 is the sleeve; 9 is the cylindrical gear; 10 is the end cover. Specific embodiments

[0035] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. However, it should not be understood that the scope of the subject matter of the present invention is limited to the following embodiments. Without departing from the above technical idea of the present invention, all modifications, substitutions, and changes made according to ordinary technical knowledge and conventional means in the art are included in the scope of the present invention.

[0036] As Figure 13 shown, it is the conical deep hole structure on the side of the outer shape of a certain product. The distance from the part surface to the bottom of the conical deep hole is 331 mm, the taper angle of the conical surface is 7.4°, and there are 3 stepped surfaces in the whole conical deep hole, forming 4 conical surfaces. The structure is complex and the precision requirements are high. At present, a lengthened end mill is used for layer-by-layer trochoidal machining. Due to the poor rigidity of the tool, vibration marks or even over-cutting are likely to occur on the side wall of the conical surface, making it difficult to meet the design requirements for the surface quality and machining dimensions of the part, and the machining efficiency is low, unable to meet the progress requirements. In addition, there is a serious tool deflection phenomenon during the cutting process, resulting in the taper of the conical deep hole not meeting the requirements and the machining accuracy being low.

[0037] In view of the above problems, the present invention designs a boring taper hole automatic adjustment device for a machining center to perform boring machining on a high-precision conical deep hole. This boring taper hole automatic adjustment device for a machining center has an automatic adjustment function, can meet the machining of different taper deep hole structures, and has high machining precision and good stability.

[0038] An automatic adjustment boring tool device for conical deep hole machining provided by the present invention is mainly used for a horizontal five-axis boring and milling machining center with a W-axis function, as Figure 1 shown. It is composed of a rack tool shank 1, a gear 9, a rack tool bar 5, a gear shaft 6, a key 3, a sleeve 8, a plug cover 7, a housing 2, and an end cover 10, etc.

[0039] Refer to Figures 2 - 12One end of the housing 2 is a flange structure, and 6 screw mounting through holes are distributed on the flange 21 for connecting and fixing with the machine tool spindle. There is a square hole in the middle of the flange 21, which is used to guide the rack tool handle 1 when it moves back and forth. The other end is a rectangular cross-section cylinder 22, and a circular hole and a depression are provided on its side. Four screw mounting holes are provided at the depression for fixing and installing the gear shaft 6, the sleeve 8 and the plug cover 7. A square guide groove 23 is provided above it, which is used to guide the rack tool rod 5 when it moves up and down. The left end is an open structure, and the end face is provided with 4 screw mounting holes for installing the end cover 10.

[0040] The gear shaft 6 is a stepped shaft with a keyway provided on it. The key is used for radial limiting of the gear 9. The sleeve 8 is a cylindrical tubular structure used for axial limiting of the gear. The plug cover 7 is provided with 4 screw mounting holes connected and fixed to the outer shell. The raised end is used to support the gear shaft 6. The gear 9 can rotate freely with the gear shaft 6. The gear 9 is used to change the direction of movement. One end of the rack tool bar 5 is used to install the blade to realize cutting processing. The side of the tool bar is a side rack structure 51. The rack tool bar 5 passes through the guide groove above the outer shell and is connected and matched with the internal gear. One end of the rack tool handle 5 is a BT-type tool handle structure 11, which is used to connect with the W axis of the horizontal five-axis boring and milling machining center to realize forward and backward movement. The other end is a rack structure 12, which is connected and matched with the gear 9. The middle part is a raised structure 13. There are 4 screw mounting holes on the end cover for connecting to the outer shell.

[0041] Installation steps: Install two pairs of gears 9 of the same specification on the gear shaft 6 passing through the side hole of the outer shell 2, limit them with the key 3 and sleeve 8, and then tighten them with the plug cover 7, so that the two pairs of gears remain matched and connected. Pass the rack tool bar 5 from the top of the outer shell through the guide groove 23 of the outer shell 2 to connect and match with the gear near the end cover 10 and enable it to move up and down. Pass the rack tool handle 1 through the central square hole of the flange 21 to connect and match with the gear near the main shaft of the machine tool and enable it to move forward and backward. The rack tool handle 1 and the rack tool bar 5 are respectively on both sides of the gear without interfering with each other. At this time, the forward and backward movement of the gear tool handle 1 is transformed into the up and down movement of the rack tool bar 5, which plays the role of reducing the diameter. Install the flange of the outer shell 2 on the main shaft of the machine tool, then start the tool change command to connect the rack tool handle 1 to the machine tool, and finally install the end cover 10 to complete the installation.

[0042] Working principle: After the machine tool spindle is connected to the boring tool device, start the machine tool to make the machine tool spindle drive the boring tool device to rotate and move forward and backward, so that the cutting blade on the rack cutter bar 5 rotates accordingly to realize the boring machining of cylindrical holes. In a horizontal five-axis boring and milling machining center with W-axis function, the up and down movement of the rack cutter bar 5 is realized by the forward and backward movement of the W-axis to achieve the variable diameter function. By changing the protruding overhang length of the W-axis, boring machining of cylindrical holes with different diameters within a certain range can be satisfied. When the motion relationship between the W-axis and the spindle is a linear ratio, the boring machining of tapered holes can be realized. When the motion relationship between the W-axis and the spindle is an arbitrary ratio, boring machining of deep holes with different shapes can be realized.

[0043] Define the feed speed of the spindle moving forward and backward as F1, and the feed speed of the W-axis moving forward and backward as F2. Since the gear only plays a role in changing the direction of motion, the feed speed of the rack cutter bar moving up and down is also F2. The taper of the tapered deep hole is α. From this, the following relational expression can be obtained:

[0044]

[0045] According to the present invention, by changing the linear ratio of the motion of the rack tool holder and the rack cutter bar, boring machining of deep holes with different tapers within a certain range can be realized. The boring tool device realizes the boring machining of tapered deep holes. The boring tool device includes mechanisms such as a motion direction conversion mechanism, a rack cutter bar structure, and a rack tool holder structure. On a machine tool with W-axis function, the variable diameter motion of the rack cutter bar is driven by the forward and backward movement of the W-axis of the machine tool. The forward and backward movement of the machine tool spindle drives the boring tool device to move forward and backward, and the rotation of the machine tool spindle drives the boring tool device to rotate, so as to realize the variable diameter linear boring machining of the rack cutter bar. By changing the linear ratio of the motion of the rack tool holder and the rack cutter bar, boring machining of deep holes with different tapers within a certain range can be realized. The boring tool device has a compact structure and good rigidity. When performing boring machining of tapered deep holes, it has the advantages of high machining accuracy, good surface quality, stable and reliable quality, and high machining efficiency.

[0046] The above has introduced in detail an automatic adjustment device for boring tapered holes in a machining center provided by the present invention. Specific examples are used in this article to elaborate on the structure and working principle of the present invention. The description of the above embodiments is only used to help understand the method and core idea of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An automatic adjusting device for boring taper holes on a machining center, characterized in that: It comprises a rack tool handle (1) arranged in a housing (2), one end of the rack tool handle (1) arranged in the housing is gear-connected with a gear (9), and the gear (9) is gear-connected with a rack tool rod (5) in the vertical direction; The other end of the rack tool handle (1) is connected to the W axis of the machine tool, and the rack tool rod (5) is moved up and down by the forward and backward movement of the W axis. The end surface of the housing (2) is connected to the main shaft of the machine tool, and the main shaft drives the housing (2) to realize the rotation and forward and backward movement of the rack tool rod (5) on the housing (2).

2. The automatic adjusting device for boring taper holes of the machining center according to claim 1, characterized in that: The housing (2) is formed by integrating a flange (21) and a cylinder (22). The inner end of the flange (21) is provided with a stepped hole formed by a square hole and a cylindrical hole. The inner side of the cylinder (22) is provided with a circular hole and a depression. A square guide groove (23) is provided on the top of the cylinder. The other end of the cylinder (22) is an open structure.

3. The automatic adjusting device for boring taper holes of a machining center according to claim 1, characterized in that: One end of the rack tool handle (1) is a BT-type tool handle structure (11), and the other end is a rack structure (12). A protrusion structure (13) is also provided on the rack tool handle (1); The protruding structure (13) of the rack tool handle (1) is snap-fitted into the square hole of the housing (2) to achieve guiding and limiting.

4. The automatic adjusting device for boring taper holes of a machining center according to claim 1, characterized in that: A blade (4) is installed at one end of the rack knife bar (5), and the side surface of the knife bar is a side rack structure (51). The rack knife bar (5) passes through the guide groove (23) above the shell (2) and is connected and matched with the internal gear (9).

5. The automatic adjusting device for boring taper holes of a machining center according to claim 1, characterized in that: The gear (9) is a pair of gears connected by inclined meshing, each gear is fixed by a gear shaft (6), and a sleeve (8) is also provided on the gear for axial limiting, the gear obliquely arranged at the lower end meshes with the rack structure (12) of the rack tool handle (1), and the gear obliquely arranged at the upper end meshes with the side rack structure (51) of the rack tool rod (5).

6. The automatic adjustment device for boring taper holes of a machining center according to claim 5, characterized in that: The gear shaft (6) is a stepped shaft, on which a keyway is provided, which is used for radial limiting of the gear (9); the sleeve (8) is a cylindrical tubular structure, which is used for axial limiting of the gear (9); one end of the gear shaft (6) is also connected to a plug cover (7), and the plug cover (7) is provided with a screw mounting hole for being connected and fixed to the housing (2), and the protruding end thereof is used for supporting the gear shaft (6).

7. The automatic adjusting device for boring taper holes of the machining center according to claim 2, wherein: The opening structure of the cylinder on the outer shell (2) is matched with an end cover (10).

8. The automatic adjusting device for boring taper holes of a machining center according to claim 2 or 3, characterized in that: The end surface of the flange (21) is provided with a plurality of screw mounting through holes for being connected and fixed to the main shaft of a machine tool, and the BT-type tool holder structure (11) end of the rack tool holder (1) is connected to the W axis of the machine tool.

9. The automatic adjusting device for boring taper holes of a machining center according to claim 8, characterized in that: The feed speed of the spindle moving forward and backward is F1, and the feed speed of the W axis moving forward and backward is F2. The ratio of F1 to F2 is equal to the taper α of the tapered deep hole.

Images