CN114713869A - Prism inner hole forming turning tool - Google Patents

Abstract

The invention provides a prism inner hole forming turning tool which comprises a tool bit, a tool apron and a tool bar, wherein the tool apron is provided with a tool groove, the tool bit is arranged in the tool groove, a main cutting edge and an auxiliary cutting edge are formed on the tool bit, a rotating shaft formed by rotation of a workpiece is superposed with a central shaft of the tool bar, the tool bar drives the tool bit to feed axially, and the main cutting edge is vertical to the axial feeding direction of the tool bit; a front cutter face, a main rear cutter face and an auxiliary rear cutter face are formed on the cutter head, the main cutting edge is formed at the intersection line of the front cutter face and the main rear cutter face, and the auxiliary cutting edge is formed at the intersection line of the front cutter face and the auxiliary rear cutter face; an included angle beta is formed between the main cutting edge and the auxiliary cutting edge, the included angle beta is more than or equal to 80 degrees and less than 90 degrees, and an inner hole is formed only by axially feeding the main cutting edge from the end face of the workpiece to the interior of the workpiece. The invention adopts an axial feed mode, thereby avoiding the generation of hyperbolic curve errors and further ensuring that the machining precision of the inner hole meets the tolerance requirement.

Description

Prism inner hole forming turning tool

Technical Field

The invention relates to the field of turning tool structures, in particular to a prism inner hole forming turning tool.

Background

The boring cutter is one of hole machining cutters, an inner hole boring cutter is generally adopted to machine an inner hole structure in the prior art, and during machining of an inner hole, due to the limitation of the rigidity of the boring cutter, an obvious cutter back-off phenomenon exists during machining of the inner hole, and the requirement of form and position tolerance is difficult to guarantee, so that parts of a machined finished product are prone to being subjected to an offset load effect after being connected in a threaded mode, and the performance of the product is reduced.

In order to solve the problem of inner hole machining by a boring cutter, a turning tool is used and inner hole machining is performed by adopting a radial feed mode, as shown in fig. 1, a main cutting edge and an auxiliary cutting edge are formed on a tool bit, wherein the main cutting edge is perpendicular to a radial feed direction, and the auxiliary cutting edge is parallel to the radial feed direction f, in the turning tool structure schematic diagram of the radial feed in the prior art.

In order to ensure the strength and sharpness of the tool bit, a rake angle needs to be ground, a rake face where the rake angle is located intersects with the main cutting edge, the angle of the rake angle directly affects the slope of the main cutting edge, based on the motion cause analysis of a machine tool, the rake angle simultaneously cuts an inner hole in the inner hole forming process of radial feed, a hyperbolic error is easily caused, the larger the rake angle is, the more remarkable the formed inner circle presents a bell mouth shape, the more remarkable the hyperbolic error is, and the processing precision of the inner hole is affected.

In view of the above, there is a need for an improved turning tool structure in the prior art to solve the above problems.

Disclosure of Invention

The invention aims to disclose a prism inner hole forming turning tool which is used for solving the problem that radial feed is easy to generate hyperbolic curve errors in the prior art, and adopts an axial feed mode so as to avoid the generation of the hyperbolic curve errors and further ensure that the inner hole machining precision meets the tolerance requirement.

In order to achieve the purpose, the invention provides a prism inner hole forming turning tool which comprises a tool bit, a tool apron and a tool bar, wherein the tool apron is provided with a tool groove, the tool bit is arranged in the tool groove, a main cutting edge and an auxiliary cutting edge are formed on the tool bit, a rotating shaft formed by rotation of a workpiece is superposed with a central shaft of the tool bar, the tool bar drives the tool bit to axially feed, and the main cutting edge is vertical to the axial feeding direction of the tool bit;

a front cutter face, a main rear cutter face and an auxiliary rear cutter face are formed on the cutter head, the main cutting edge is formed at the intersection line of the front cutter face and the main rear cutter face, and the auxiliary cutting edge is formed at the intersection line of the front cutter face and the auxiliary rear cutter face;

an included angle beta is formed between the main cutting edge and the auxiliary cutting edge, the included angle beta is more than or equal to 80 degrees and less than 90 degrees, and an inner hole is formed only by the axial feed of the main cutting edge from the end surface of the workpiece to the interior of the workpiece.

As a further improvement of the invention, the front tool face intersects with the tool end face of the tool bit, a front angle alpha is formed between the front tool face and the base surface Pr, and the front angle alpha is 5-10 degrees

As a further development of the invention, the angle β is 85 ° and the rake angle α is 7 °.

As a further improvement of the present invention, the main flank and the cutting plane Ps form a relief angle γ, and the relief angle γ is equal to the rake angle α.

As a further improvement of the invention, the knife groove comprises a first groove wall and a second groove wall, the first groove wall is parallel to the base surface Pr, the second groove wall is parallel to the base surface Po, and the side edges of the first groove wall and the second groove wall are intersected and vertical;

the utility model provides a tool bit, including first cell wall, second cell wall and buffer wall, the knife end face one side that the tool bit was kept away from to the second cell wall extends the buffer wall towards vice back knife face, the buffer wall is 1/4 circular arc walls, the buffer wall side is crossing with first cell wall, all laminate between tool bit and first cell wall, second cell wall and the buffer wall.

As a further improvement of the invention, a connecting rod is integrally formed on the tool apron, one end of the connecting rod, which is far away from the tool end surface of the tool bit, is embedded into a tool bar, a bolt penetrates through the tool bar along the axis direction, and the bolt is in threaded connection with the connecting rod;

the cutter bar is an axial hollow conical amplitude transformer, and a clamping plane is formed on the cutter bar.

As a further improvement of the invention, a transition surface is formed on the cutter head, the secondary flank surface is connected between the transition surface and the main flank surface, the side edge of the transition surface is intersected with the rake surface, an included angle delta is formed between the secondary flank surface and the transition surface, and the included angle delta is 130 degrees;

an included angle epsilon is formed between the transition surface and the orthogonal plane Po', and the included angle epsilon is 45 DEG

As a further improvement of the invention, the front cutter face is far away from the cutter end face of the cutter head to form a chip groove which is 1/4 circular arc grooves.

As a further improvement of the invention, an extension surface is formed between the main rear cutter surface and the cutter end surface of the cutter head, an included angle theta is formed between the extension line of the extension surface and the cutting plane Ps, the included angle theta is 45 degrees, and the side edge of the extension surface is intersected with the front cutter surface.

As a further improvement of the invention, the joint between the main cutting edge and the auxiliary cutting edge is a knife edge, and the knife edge is an 1/4 arc chamfer.

Compared with the prior art, the invention has the beneficial effects that:

the cutting tool has the advantages that the cutting feed direction of the tool bit is improved, the radial cutting in the prior art is changed into the axial cutting, the main cutting edge is perpendicular to the axial cutting feed direction, an included angle needs to exist between the sharpness degree of the tool bit and a base surface Pr of the tool bit, the included angle is the front angle alpha, the main cutting edge is formed at the intersection line of the front cutting edge and the main rear cutting edge and is perpendicular to the axial cutting feed direction, the angle between the main cutting edge and the auxiliary cutting edge is reduced, the auxiliary cutting edge does not participate in the hole forming action, the edge slope of the main cutting edge is not influenced by the front angle alpha, the problem that the radial cutting causes hyperbolic error can be effectively avoided in the hole forming process, and the hole forming precision can meet the tolerance requirement.

Drawings

FIG. 1 is a schematic view of a prior art radial feed tool tip configuration;

FIG. 2 is a schematic view of the integral assembly of the cutter head and the cutter bar;

FIG. 3 is a perspective view of the spatial relationship of the cutting head and the tool holder;

FIG. 4 is an exploded view of the assembled relationship of the tool bit and tool holder;

FIG. 5 is a right side view of the tool bit and tool holder in an assembled condition;

FIG. 6 is an enlarged view of portion A of FIG. 5;

FIG. 7 is an elevation view of the cutting head and tool holder in an assembled condition;

fig. 8 is a sectional view of a radial cutting structure of the cutter bar.

Detailed Description

The present invention is described in detail with reference to the embodiments shown in the drawings, but it should be understood that these embodiments are not intended to limit the present invention, and those skilled in the art should understand that functional, methodological, or structural equivalents or substitutions made by these embodiments are within the scope of the present invention. It will be understood that the terms "center," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like, as used herein, are intended to refer to an orientation or positional relationship illustrated in the drawings, which is for convenience and simplicity of description, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and is not to be construed as limiting the present disclosure.

Example (b):

the embodiment discloses a prism inner hole forming turning tool which is used for forming an inner hole of a workpiece.

Referring to fig. 2 to 4, the shock-absorbing female forming lathe tool includes: tool bit 1, blade holder 2 and cutter arbor 3, be formed with main cutting edge 111 and vice cutting edge 121 on the tool bit 1, set up sword groove 21 on the blade holder 2, tool bit 1 inlays in sword groove 21, cutter arbor 3 drives blade holder 2 and 1 axial of tool bit and feeds to work piece department and carries out the pore-forming processing, the axial direction of feeding is V shown in figure 2 and figure 3, main cutting edge 111 perpendicular to axial direction of feeding, the length of main cutting edge 111 is 1.4mm, the tolerance range is 0.01mm, the work piece rotates during the pore-forming, the pivot that the work piece rotated and forms coincides with cutter arbor 3's axis C, the work piece radius is shown for r in figure 2, work piece pore-forming diameter is shown for r in figure 2

As shown.

Referring to fig. 3, the base surface Pr is a plane defined by a selected point o of the main cutting edge 111 and parallel to the axial feed direction V, the cutting plane Ps is a plane defined by the main cutting edge extending in a direction perpendicular to the base surface, the orthogonal plane Po is a plane defined by the selected point o of the main cutting edge 111 and perpendicular to both the base surface Pr and the cutting plane Ps, and the orthogonal plane Po' is a plane parallel to Po, and is referred to only as a position reference.

As shown in fig. 3 to 7, the cutting insert 1 is formed with a rake surface 11, a major flank surface 13, and a minor flank surface 12, wherein an intersection of the rake surface 11 and the major flank surface 13 is a major cutting edge 111, an intersection of the rake surface 11 and the minor flank surface 12 is a minor cutting edge 121, a cutting edge 18 is formed at a junction of the major cutting edge 111 and the minor cutting edge 121, the cutting edge 18 is an 1/4 arc angle, and the radius of the cutting edge 18 is 0.2 mm. An included angle beta is formed between the main cutting edge 111 and the auxiliary cutting edge 121, and the included angle beta is more than or equal to 80 degrees and less than 90 degrees;

in order to achieve better effect, the included angle beta can be 81-89 degrees;

in order to achieve better effect, the included angle beta can be 82-88 degrees;

in order to achieve better effect, the included angle beta can be 83-87.5 degrees;

in order to achieve a better effect, the included angle beta can be 84.5-86 degrees, and in the embodiment, the included angle beta is 85 degrees;

the front tool face 11 is intersected with the tool end face 14 of the tool bit 1, a front angle alpha is formed between the front tool face 11 and the base surface Pr, and the front angle alpha is 5-10 degrees;

for better effect, the front angle α may be 6 °, 7 °, 8 °, 9 °, and the front angle α is 7 ° in this embodiment.

When the inner hole of a workpiece is formed, the cutter bar 33 and the workpiece are respectively arranged on a machine tool, when the hole is formed, the workpiece rotates, the cutter bar 33 drives the cutter head 11 to feed along the axial V direction, the cutter head enters the workpiece from the end face of the workpiece, and the main cutting edge 111111 forms the inner hole in the workpiece. The rake angle alpha directly affects the sharpness of the tool bit 11, the position of the main flank 13 can be determined according to the direction v perpendicular to the axial feeding direction of the main cutting edge 111, the main cutting edge 111 is a horizontal line segment on the base surface Pr, and the main cutting edge 111 is a point on the orthogonal plane Po, so that the rake angle alpha formed between the rake surface 11 and the base surface does not affect the edge slope of the main cutting edge 111, and a hyperbolic error caused by the effect of the edge slope in the radial feeding direction f is effectively avoided.

Because the positions of the rake face 11 and the main flank face 13 are determined, the position of the secondary flank face 12 can be determined, the projection of the secondary cutting edge 121 formed at the intersection line of the rake face 11 and the secondary flank face 12 on the base surface Pr is an inclined line segment, the angle of the rake angle α can be obtained to affect the edge slope of the secondary cutting edge 121, when the included angle between the main flank face 13 and the secondary flank face 12 is equal to 90 °, the secondary radial cutting can be caused to the inner hole by the secondary cutting edge 121 in the axial feed process, and the slope of the edge of the secondary cutting edge 121 can cause the generation of a hyperbolic error, so the included angle β in the embodiment is 85 °, the secondary cutting edge 121 does not contact with the workpiece in the inner hole forming process, the hole forming operation is performed only by the main cutting edge 111, and the occurrence of the secondary radial cutting is effectively avoided, so as to improve the inner hole forming accuracy.

The front angle value of lathe tool is in 5 ~ 15 among the machining, and tool bit 11 is A320 type lathe tool in this embodiment, has the blade and welds easily, the convenient and high advantage of durability of sharpening, and 7 front angle alpha has good sharpness and intensity through the actual production test concurrently, does benefit to the hole and takes shape and have longer life cycle.

Referring to fig. 7, a relief angle γ is formed between the main flank 13 and the cutting plane Ps, the relief angle γ is equal to the rake angle α, and the relief angle is an important structure of the turning tool, and functions to reduce a contact surface between the tool and a workpiece when the tool is cutting, reduce a cutting force of the tool cutting, reduce heat generation when the tool is cutting, prolong a service life of the tool, and protect surface roughness of a cut surface.

Referring to fig. 4 to 7, a transition surface 15 is formed on the cutter head 1, the secondary flank 12 is connected between the transition surface 15 and the primary flank 13, the side edge of the transition surface 15 is intersected with the rake surface 11, an included angle δ is formed between the secondary flank 12 and the transition surface 15, and the included angle δ is 130 degrees; the transition surface 15 forms an angle epsilon with the orthogonal plane Po', the angle epsilon being 45 deg.. The position of the front tool face 11, which is far away from the tool end face 14 of the tool bit 1, forms a chip groove 16, wherein the chip groove 16 is an 1/4 circular arc groove, and the radius of the chip groove 16 is 2 mm. The inclination angle of the transition surface 15 is determined by the values of the included angle delta and the included angle epsilon, the transition surface 15 and the chip removal groove 16 respectively form a chip removal space, and the scrap iron can be disconnected and does not wind at the transition surface 15 and the chip removal groove 16; the outflow direction of the scrap iron can be controlled to keep the precision of the formed surface; cutting resistance can be reduced, and the service life of the cutter head 1 is prolonged.

Referring to fig. 4, an extension surface 17 is formed between the main flank surface 13 and the rake face 14 of the tool bit 1, an angle θ is formed between an extension line of the extension surface 17 and the cutting plane Ps, the angle θ is 45 °, and a side edge of the extension surface 17 intersects with the rake face 11. In the process of cutting in the axial cutting feed direction V, the intersection line of the tool end surface 14 and the rake surface 11 of the tool bit 1 firstly performs axial cutting on a workpiece to form an auxiliary inner hole with the radius equal to the length of the intersection line of the tool end surface 14 and the rake surface 11, the intersection line of the extension surface 17 and the rake surface 11 performs radial cutting on the workpiece in the process of forming the inner hole by axial cutting feed, the main cutting edge 111 forms a main inner hole in the workpiece by axial V feeding, the radius difference between the main inner hole and the auxiliary inner hole is the sum of the length of the main cutting edge 111 and the projection length of the extension surface 17 on a base surface Po, the main inner hole and the auxiliary inner hole form a step hole, the radial cutting at the joint of the extension surface 17 and the rake surface 11 forms a chamfer between the main inner hole and the auxiliary inner hole, the step hole has the function of preventing the head of the bolt 31 from protruding out of the surface of the workpiece, the extension surface 17 is arranged on the surface of the hole and forms a chamfer of the step hole at the same time of forming the step hole, reduce friction and impact between screw and the bolt 31 during the assembly, and accomplished the shaping of step hole and chamfer in step, effectively simplify the cutting process to the setting of extension plane 17 has effectively strengthened the intensity of main cutting edge 111 in the structure of tool bit 1, has prolonged the life of tool bit 1.

Referring to fig. 4, the pocket 21 includes a first pocket wall 211 and a second pocket wall 212, the first pocket wall 211 is parallel to the base Pr, the second pocket wall 212 is parallel to the base Po, and the first pocket wall 211 and the second pocket wall 212 intersect at their sides and are perpendicular; the side, away from the tool end face 14 of the tool bit 1, of the second groove wall 212 extends out of the buffer wall 213 towards the minor flank 12, the buffer wall 213 is an 1/4 arc wall, the radius of the buffer wall 213 is 10mm, the side edge of the buffer wall 213 intersects with the first groove wall 211, and the tool bit 1 is attached to the first groove wall 211, the second groove wall 212 and the buffer wall 213. The tool bit 1 is installed in the tool groove 21 in a welding mode, the main cutting edge 111 is stressed in the axial cutting feed hole forming process, impact force exists between the tool bit 1 and the buffer wall 213, the buffer wall 213 is set to be an 1/4 arc wall, the impact force can be buffered, serious abrasion between the tool bit 1 and the tool groove 21 is avoided, and the tool bit 1 and the tool apron 2 are both protected.

Referring to fig. 2 and 8, a connecting rod 22 is integrally formed on the tool apron 2, one end of the connecting rod 22, which is far away from the tool end surface 14 of the tool bit 1, is embedded into the tool bar 3, a bolt 31 penetrates through the tool bar 3 along the axial direction, and the bolt 31 is in threaded connection with the connecting rod 22; the cutter bar 3 is a conical amplitude transformer and is hollow inside. The roughness of the surface of the workpiece is related to the feed amount of the cutter and the vibration generated during cutting of the cutter, and during the cutting process of the cutter, the cutting force is dynamically changed due to the cutting depth change, so that the cutter head 1 generates self-excited vibration, and the vibration direction is vertical to the axial feed direction V, so that the roughness of the surface of the part is influenced. In order to avoid the self-excited vibration from being close to the natural frequency of the tool rest, the structural design of the hollow tool bar and the conical amplitude variation is adopted, so that the axial cutting frequency-reducing anti-seismic effect is achieved, and the requirement on the surface roughness of a workpiece is met. The tool shank 3 is formed with a clamping plane 32 for stable mounting of the tool shank 3 on a machine tool.

The above-listed detailed description is merely a detailed description of possible embodiments of the present invention, and it is not intended to limit the scope of the invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention are intended to be included within the scope of the present invention.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present specification describes embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and it is to be understood that all embodiments may be combined as appropriate by one of ordinary skill in the art to form other embodiments as will be apparent to those of skill in the art from the description herein.

Claims (10)

1. The utility model provides a prism inner hole forming turning tool, includes tool bit, blade holder and cutter arbor, sets up the sword groove on the blade holder, and the tool bit is installed in the sword groove, is formed with main cutting edge and vice cutting edge on the tool bit, and the work piece rotates the pivot that forms and the center pin coincidence of cutter arbor, its characterized in that:

the cutter bar drives the cutter head to feed axially, and the main cutting edge is perpendicular to the axial feeding direction of the cutter head;

a front cutter face, a main rear cutter face and an auxiliary rear cutter face are formed on the cutter head, the main cutting edge is formed at the intersection line of the front cutter face and the main rear cutter face, and the auxiliary cutting edge is formed at the intersection line of the front cutter face and the auxiliary rear cutter face;

an included angle beta is formed between the main cutting edge and the auxiliary cutting edge, the included angle beta is more than or equal to 80 degrees and less than 90 degrees, and an inner hole is formed only by the axial feed of the main cutting edge from the end surface of the workpiece to the interior of the workpiece.

2. The prism inner hole forming turning tool as claimed in claim 1, characterized in that: the front cutter face is intersected with the cutter end face of the cutter head, a front angle alpha is formed between the front cutter face and the base face Pr, and the front angle alpha is 5-10 degrees.

3. The prism inner hole forming turning tool as claimed in claim 2, characterized in that: the included angle beta is 85 degrees, and the rake angle alpha is 7 degrees.

4. The prism inner hole forming turning tool according to claim 3, characterized in that: and a back angle gamma is formed between the main back tool face and the cutting plane Ps, and the back angle gamma is equal to the front angle alpha.

5. The prism inner hole forming turning tool as claimed in claim 1, characterized in that: the cutter groove comprises a first groove wall and a second groove wall, the first groove wall is parallel to the base surface Pr, the second groove wall is parallel to the base surface Po, and the side edges of the first groove wall and the second groove wall are intersected and vertical;

the utility model provides a tool bit, including first cell wall, second cell wall and buffer wall, the knife end face one side that the tool bit was kept away from to the second cell wall extends the buffer wall towards vice back knife face, the buffer wall is 1/4 circular arc walls, the buffer wall side is crossing with first cell wall, all laminate between tool bit and first cell wall, second cell wall and the buffer wall.

6. The prism inner hole forming turning tool according to claim 5, wherein: a connecting rod is integrally formed on the tool apron, one end, far away from the tool end face of the tool bit, of the connecting rod is embedded into a tool bar, a bolt penetrates through the tool bar along the axis, and the bolt is in threaded connection with the connecting rod;

the cutter bar is an axial hollow conical amplitude transformer, and a clamping plane is formed on the cutter bar.

7. The prism inner hole forming turning tool according to claim 3 or 4, characterized in that: a transition surface is formed on the cutter head, the auxiliary rear cutter surface is connected between the transition surface and the main rear cutter surface, the side edge of the transition surface is intersected with the front cutter surface, an included angle delta is formed between the auxiliary rear cutter surface and the transition surface, and the included angle delta is 130 degrees;

an included angle epsilon is formed between the transition surface and the orthogonal plane Po', and the included angle epsilon is 45 degrees.

8. A prism inner hole forming turning tool according to claim 7, characterized in that: the front tool face is far away from the tool end face of the tool bit to form a chip removal groove, and the chip removal groove is an 1/4 arc groove.

9. The prism inner hole forming turning tool as claimed in claim 8, characterized in that: an extension surface is formed between the main rear cutter surface and the cutter end surface of the cutter head, an included angle theta is formed between the extension line of the extension surface and the cutting plane Ps, the included angle theta is 45 degrees, and the side edge of the extension surface is intersected with the front cutter surface.

10. The prism inner hole forming turning tool as claimed in claim 1, characterized in that: the joint between the main cutting edge and the auxiliary cutting edge is a cutter point which is an 1/4 arc chamfer.

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