JP2010184339A - Tap with fluid supply hole - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve fluid supply performance of a tap with a fluid supply hole in which the fluid is discharged to an outer peripheral side along a blocking member by integrally fixing the blocking member to the tip of a tap body and further improve tool life. <P>SOLUTION: In the tap with a fluid supply hole, a spherical body 30 is disposed in a large diameter hole part 28 provided at a tip opening part of an oil hole 20 so that the fluid (such as a lubricating agent) supplied through the oil hole 20 is smoothly flown to the outer peripheral side along an internal wall surface of the large diameter hole part 28 and smoothly flown inside a discharge passages 36 formed in the radial direction. This suppresses the occurrence of the generation of turbulent flow such as a swirl, reduces pressure loss, discharges the fluid nearly uniformly through a plurality of the discharge passages 36, and increases the discharge amount of the fluid so that outstanding fluid supply performance (such as lubrication performance) is obtained and consequently, excellent tool life can be obtained even when a tapping work is performed to a through-hole. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a tap with a fluid supply hole, and in particular, with a fluid supply hole of a type in which fluid is discharged to the outer peripheral side along the closure member by integrally fixing the closure member at the tip of the tap body. The present invention relates to a technique for improving the fluid supply performance of a tap.

  (a) A tap body provided with a male thread portion for processing a female screw at the outer peripheral portion of the tip and provided with a fluid supply hole so as to pass through the tool axis O and open at the tip surface And (b) a closing member that is integrally fixed so as to be in close contact with the tip surface of the tap body, and closes the tip opening of the fluid supply hole, and (c) the tip surface of the tap body, A plurality of fluids that are formed in a radial direction so as to communicate with the fluid supply hole at a boundary portion with the facing surface of the closing member that is brought into close contact with the distal end surface, and discharge the fluid supplied from the fluid supply hole to the outer peripheral side. And a tap with a fluid supply hole having a discharge passage. The tap described in Patent Document 1 is an example thereof, which is a cutting tap, and the guide member functions as a closing member. According to such a tap with a fluid supply hole, a discharge passage is provided in the radial direction at the tip of the tap so that the fluid is discharged to the outer peripheral side. A fluid such as a lubricant can be appropriately sprayed in the vicinity of the processed portion.

  3A and 3B relate to the rising tap, in which FIG. 3A is a longitudinal sectional view of the tool tip section cut in parallel to the tool axis O, and FIG. 3B is a tip view of the tool tip viewed from the right side of FIG. A male screw portion 102 is provided on the outer peripheral portion of the front end of the main body 100, and an oil hole 104 is provided as a fluid supply hole so as to pass through the tool axis O and open to the front end surface 106. The external thread portion 102 has a substantially hexagonal outer peripheral surface composed of sides curved outward and is provided with a male screw thread 108 corresponding to a female thread to be processed in a spiral shape, and corresponds to the apex of the hexagonal shape. The six projecting portions 110 to be cut into the surface layer portion of the prepared hole of the workpiece to be plastically deformed, thereby raising the female screw. A disc-shaped closing member 112 is integrally fixed at the tip of the tap body 100 to close the tip opening of the oil hole 104, and the closing member 112 and the tip surface 106 of the tap body 100. The four discharge passages 114 are provided in a radial shape at the boundary between the two and a cross shape in FIG. 3 to discharge the fluid supplied from the oil hole 104 to the outer peripheral side. A tapered center hole 116 for supporting the center is provided at the front end opening of the oil hole 104, and an oil circulation groove 118 is provided at the middle position of the six protruding portions 110 in the male screw portion 102, respectively. Is formed.

Utility Model Registration No. 3025679

  However, in such a conventional tap with fluid supply holes, the fluid supply performance (such as lubrication performance) as expected cannot always be obtained, and the effect of improving the tool life cannot be sufficiently obtained. More specifically, referring to the conventional example of FIG. 3, the fluid that has circulated in the oil hole 104 bounces back almost straight against the closing member 112 and converges in the presence of the tapered center hole 116 to converge. 104, the pressure is likely to cause a turbulent flow such as a spiral, the pressure when discharged from the discharge passage 114 decreases, the discharge amount decreases, and the fluid discharged from the plurality of discharge passages 114 It is considered that the discharge amount of the liquid becomes uneven and the fluid supply performance is impaired. In general, if there is a part with a large flow cross-sectional area in the middle of the flow path of the fluid, a turbulent flow such as spiraling occurs due to a change in flow velocity and the like, and pressure loss occurs. For this reason, it is conceivable that this causes a pressure loss and impairs the fluid supply performance.

  The present invention has been made against the background of the above circumstances. The object of the present invention is to provide a closing member integrally fixed to the tip of the tap main body so that fluid flows to the outer peripheral side along the closing member. An object of the present invention is to improve the fluid supply performance of a tap with a fluid supply hole of a discharged type and further improve the tool life.

  In order to achieve this object, the first invention provides (a) a male thread portion for machining a female thread at the outer periphery of the tip, and a fluid supply hole extending vertically through the tool axis O. A tap main body that is provided and opened at the front end surface; and (b) a blocking member that is integrally fixed so as to be in close contact with the front end surface of the tap main body and closes the front end opening of the fluid supply hole. And (c) a boundary portion between the tip surface of the tap body and the facing surface of the closing member that is brought into close contact with the tip surface, is formed in a radial direction so as to communicate with the fluid supply hole, and the fluid supply In a tap with a fluid supply hole having a plurality of discharge passages for discharging the fluid supplied from the hole to the outer peripheral side, (d) at the tip opening where the fluid supply hole opens at the tip surface of the tap body, A large-diameter hole that increases the diameter of the opening end is provided. And (e) a guide member that guides the fluid supplied through the fluid supply hole so as to flow along the inner wall surface of the large diameter hole portion to the outer peripheral side. It is characterized by being.

  According to a second invention, in the tap with a fluid supply hole according to the first invention, the guide member is a sphere configured separately from the tap body and the closing member, and is surrounded by the large-diameter hole portion and the closing member. It is characterized by being housed in a confined space.

  According to a third aspect of the present invention, in the tap with a fluid supply hole according to the second aspect of the present invention, the opposing surface of the closing member is substantially concentric with the tool axis O when the sphere is pressed by the pressure of the fluid. A positioning recess for positioning the sphere is provided.

  According to a fourth aspect of the present invention, in the tap with a fluid supply hole according to the first aspect of the invention, the guide member is integrally formed concentrically with the tool axis O so as to protrude toward the inside of the large-diameter hole portion on the opposing surface of the closing member. It is characterized by being a guide protrusion having a smaller diameter toward the distal end side.

  In such a tap with a fluid supply hole, the fluid supplied through the fluid supply hole passes along the inner wall surface of the large-diameter hole portion in the large-diameter hole portion provided at the tip opening of the fluid supply hole. Since the guide member that guides the fluid to flow to the outer peripheral side is accommodated, the fluid supplied from the fluid supply hole smoothly flows to the outer peripheral side along the inner wall surface of the large-diameter hole, It becomes possible to smoothly flow into the formed discharge passage. As a result, the occurrence of turbulent flow such as spirals is suppressed and the pressure loss is reduced, fluid is discharged from the plurality of discharge passages substantially uniformly, and the discharge flow rate is increased, resulting in excellent fluid supply. Performance can be obtained, and an excellent tool life can be obtained even when tapping a through hole.

  In the second invention, since the guide member is a sphere and is accommodated in a space surrounded by the large-diameter hole portion and the closing member, a significant design change is not necessarily required, and the guide member can be easily implemented.

  In the third invention, a positioning recess is provided on the opposing surface of the closing member, and the sphere is positioned substantially concentrically with the tool axis O, so that the fluid supplied from the fluid supply hole is substantially uniformly surrounded by the sphere. The fluid is discharged more uniformly from the plurality of discharge passages, and the fluid supply performance is further improved.

  In the fourth aspect of the invention, since the guide member is constituted by the guide protrusion provided integrally with the closing member, a significant design change is not necessarily required, and the guide member can be simply implemented and supplied from the fluid supply hole. The fluid can be discharged to the outer peripheral side substantially uniformly by the guide protrusions fixed in position and discharged more uniformly from the plurality of discharge passages, and the fluid supply performance is further improved. Further, as compared with the case where a guide member such as a sphere is incorporated separately, the assembling work when the closing member is integrally fixed to the tap body is facilitated.

It is a figure which shows an example at the time of this invention being applied to the heightening tap with an oil hole, (a) is a front view seen from the direction orthogonal to the tool axis O, (b) is a tool center axis O. (C) is a tip view from the right side of (b), (d) is a tip view of the tap body before assembling the closing member and the sphere, and (e) is a closing view. It is the end elevation which looked at the member from the counter surface side. FIGS. 5A and 5B are diagrams for explaining another embodiment of the present invention, and FIGS. 5A and 5B are longitudinal sectional views corresponding to FIG. It is a figure which shows an example of the conventional raising tap with an oil hole, (a) is a longitudinal cross-sectional view corresponding to (b) of FIG. 1, (b) is a front end view corresponding to (c) of FIG.

  The tap with fluid supply hole of the present invention is a raised tap (rolling tap) in which the external thread portion has a polygonal shape (triangular or more), and the surface layer portion of the pilot hole is plastically deformed by the protruding portion to form a female thread. Although preferably applied, the present invention can also be applied to a cutting tap in which a female blade is provided with a cutting edge to cut a female screw. In the case of the raised tap, particularly sufficient lubricating oil is required, so that the lubrication performance is improved and the tool life is greatly improved by applying the present invention.

  It is desirable that three or more discharge passages formed at the boundary portion between the tap body and the closing member are provided radially at equal angular intervals around the tool axis O, but a pair of discharge passages are arranged on a straight line perpendicular to the tool axis O. These discharge passages may be provided, or they may be provided at unequal angular intervals. In addition to the straight groove, various modes are possible, such as a circular arc shape smoothly curved toward the tool rotation direction side or the reverse rotation direction side toward the outer peripheral side.

  The discharge passage has a cross section provided on at least one of the tip surface of the tap main body and the opposing surface of the closing member, and is formed by a linear groove such as a semicircular arc shape or a rectangle, a curved groove, or the like. Only one of the tip surface of the tap body and the facing surface of the closing member is provided with a groove, and the other may be a flat surface, or both the tip surface of the tap body and the facing surface of the closing member face each other. A groove may be provided in each part, and a discharge passage having a circular cross section may be formed by combining both of the grooves.

  The flow cross-sectional area of the discharge passages is preferably set so that the total flow cross-sectional area of the plurality of discharge passages is substantially the same as or smaller than the flow cross-sectional area of the fluid supply holes. Is set. The flow cross-sectional area between the large-diameter hole and the guide member may be substantially the same as or smaller than the flow cross-sectional area of the fluid supply hole, and may be substantially the same as or larger than the total flow cross-sectional area of the plurality of discharge passages. desirable.

  The closing member is integrally bonded to the tip surface of the tap body with an adhesive or the like at a portion other than the discharge passage, or is integrally fixed to the tap body by welding such as laser welding. It can also be detachably fixed by a mechanical fixing means such as a screw.

  The tap with a fluid supply hole of the present invention is preferably used particularly when a female screw is processed for a through hole, but can also be used when a female screw is processed for a blind hole. However, in the case of a blind hole, the blocking member and the guide member are not necessarily required, and can be used in the state of the tap body alone, and the blocking member and the guide member are arranged only when there is a possibility of being used for the through hole. You may make it install.

  The large-diameter hole portion may have a tapered shape like a center hole, and the center hole can be used as it is as a large-diameter hole portion. In addition to the tapered shape, a large-diameter hole having a semicircular arc shape in cross section parallel to the tool axis O or a U-shaped hole having an open side can be employed.

  The positioning recess provided on the opposing surface of the closing member to position the guide member sphere concentrically with the tool axis O is a partial spherical shape, a tapered hole, or a circle having a smaller diameter than the sphere. Any hole or the like that can be positioned substantially concentrically with the tool axis O by being engaged with the sphere is acceptable.

  The guide protrusion provided integrally with the closing member as the guide member may be configured separately from the closing member and integrally fixed to the closing member by an adhesive, welding, or the like. It may be provided integrally with the member. The shape of the guide projection is appropriately determined in consideration of the shape of the large-diameter hole portion.For example, when the large-diameter hole portion is a tapered shape, a conical shape protruding toward the inside of the tapered large-diameter hole portion and It is appropriate to do. When the cross-sectional shape parallel to the tool axis O of the large-diameter hole is a semicircular arc shape or a U-shape with an open side, the guide protrusion also has a semicircular arc-shaped cross section or a cross-sectional shape corresponding to the U-shape ( It is desirable that the tip is hemispherical and the base end is conical with a small taper angle.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a view showing a raised tap 10 with an oil hole (hereinafter simply referred to as a raised tap 10) according to an embodiment of the present invention, and (a) is a front view as viewed from a direction perpendicular to the tool axis O. (b) is a longitudinal sectional view of the tool tip section cut parallel to the tool axis O, (c) is a tip view of the tool tip viewed from the right direction of (b), and (d) is a tap before assembling the closing member and the sphere. FIG. 5E is a front end view of the main body, and FIG. The raised tap 10 has a disc-shaped closing member 14 integrally fixed to the tip of a tap body 12, and the tap body 12 includes a shank 16 attached to a main shaft via a chuck (not shown), and a female screw. And a male threaded portion 18 for rolling up (rolling) is integrally provided concentrically with the tool axis O, and an oil hole 20 is provided as a fluid supply hole so as to pass through the tool axis O vertically. And opened at the distal end surface 22. The raised tap 10 corresponds to a tap with a fluid supply hole.

  The male thread portion 18 has a regular polygonal shape consisting of sides curved outward, a substantially hexagonal cross section in this embodiment, and a thread of a male thread corresponding to a female thread to be formed on the outer peripheral surface thereof. 19 is provided in a spiral shape, and six projecting portions 24 corresponding to the hexagonal apexes bite into the surface layer portion of the prepared hole of the workpiece to be plastically deformed, thereby raising the female screw. The male screw portion 18 includes a complete mountain portion 18a in which the diameter of the protruding portion 24 is substantially constant, and a biting portion 18b in which the diameter is gradually reduced toward the distal end side. Further, oil circulation grooves 26 are formed in parallel with the tool axis O at intermediate positions in the circumferential direction of the six protruding portions 24.

  The diameter of the oil hole 20 changes in the middle of the shank 16, and the rear side of the shank 16 has a large diameter (φ3 in the embodiment) and a small diameter (φ2 in the embodiment) from the middle. At the tip opening where the oil hole 20 opens at the tip face 22 of the tap body 12, a semispherical shape, that is, a cross-sectional shape parallel to the tool axis O forms a semicircular arc shape, and the diameter dimension on the opening side increases. A substantially U-shaped large-diameter hole portion 28 whose opening side is opened is provided, and a predetermined gap is formed between the large-diameter hole portion 28 and the inner wall surface of the large-diameter hole portion 28. As described above, a spherical body (in the embodiment, a steel ball) 30 smaller than the large-diameter hole portion 28 is accommodated. The large-diameter hole portion 28 is provided in a portion where the center hole was originally formed, and after the male screw portion 18 and the like are processed by supporting the center hole so as to be rotatable around the tool axis O, It is formed by cutting or the like. The spherical body 30 corresponds to a guide member that guides the fluid supplied through the oil hole 20 to the outer peripheral side so as to flow along the inner wall surface of the large-diameter hole portion 28, and the large-diameter hole portion 28, the spherical body 30, Is determined to be substantially the same as or smaller than the flow cross-sectional area of the tool tip side portion of the oil hole 20.

  A disc-shaped closing member 14 is integrally fixed to the tip of the tap body 12 by laser welding, an adhesive, or the like, confining the sphere 30 in the large-diameter hole 28 and opening the tip of the oil hole 20. The part is blocked. The closing member 14 has the opposing surface 32 on the tap body 12 side in close contact with the distal end surface 22, and the spherical surface 30 is pressed against the opposing surface 32 by the pressure of the fluid supplied in the oil hole 20. A positioning recess 34 for positioning the sphere 30 so as to be substantially concentric with the tool axis O is provided. The positioning recess 34 has a partial spherical shape or a dish shape having substantially the same curvature as the spherical body 30. Further, four discharge passages 36 are provided so as to form a radial shape, in the embodiment, a cross shape, across the front end surface 22 of the tap body 12 and the opposing surface 32 of the closing member 14, and the large diameter from the oil hole 20. The fluid supplied through the gap between the hole 28 and the sphere 30 is discharged toward the outer peripheral side. The discharge passage 36 has a cross-shaped groove 36a formed in a cross shape on the front end surface 22 of the tap body 12, and a cross-shaped groove formed in a cross shape on the opposing surface 32 of the closing member 14. By combining with 36b, the passage has a substantially circular cross section. The flow cross-sectional areas of the four discharge passages 36 are equal to each other, and the total flow cross-sectional area is determined to be substantially the same as or smaller than the flow cross-sectional area between the large-diameter hole 28 and the sphere 30. .

  In such a raised tap 10, since the spherical body 30 is disposed in the large-diameter hole 28 provided at the tip opening of the oil hole 20, the fluid (lubricant) supplied through the oil hole 20 Etc.) smoothly flows toward the outer peripheral side along the inner wall surface of the large-diameter hole portion 28 and smoothly flows into the discharge passage 36 formed in the radial direction. As a result, the occurrence of turbulent flow such as spirals is suppressed and the pressure loss is reduced, so that fluid is discharged from the plurality of discharge passages 36 substantially uniformly, and the discharge flow rate is increased, resulting in excellent fluid flow. Supply performance (such as lubrication performance) can be obtained, and an excellent tool life can be obtained even when tapping a through hole.

  Further, in this embodiment, the spherical body 30 is used as the guide member, and is accommodated in the space surrounded by the large-diameter hole portion 28 and the closing member 14, so that it is not necessary to make a significant design change and is simply implemented. be able to.

  Further, in this embodiment, the positioning recess 34 is provided in the facing surface 32 of the closing member 14 and the sphere 30 is positioned substantially concentrically with the tool axis O, so that the fluid supplied from the oil hole 20 is the sphere. 30, the fluid is caused to flow substantially uniformly toward the outer periphery, and the fluid is discharged more uniformly from the plurality of discharge passages 36, thereby further improving the fluid supply performance.

By the way, two types of raised taps of the present invention product (rising tap 10 in FIG. 1) and a conventional product (rising tap in FIG. 3) having a nominal diameter of 14 mm and a pitch of 2 mm are prepared. As a result of investigating the number of machining holes until the tool life is reached after performing tapping, the product of the present invention is capable of machining 4000 holes despite severe conditions where the peripheral speed is faster than the conventional product. A tool life superior to that of the conventional product having 3500 holes was obtained. The tool life was determined by gauge out (GP out) due to wear of the protrusion 24. Except for the peripheral speed, the present invention product and the conventional product have the same processing conditions.
"Processing conditions"
Workpiece: Carbon steel for machine structure (JIS-S45C)
Processing depth: 28mm (through hole)
Peripheral speed: 35 m / min (present product), 30 m / min (conventional product)
Feeding speed: 2mm / rev
Lubricating oil: Chlorine-free water-soluble (2 MPa)

  Next, another embodiment of the present invention will be described. In the following embodiments, parts that are substantially the same as those in the above embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  2 (a) and 2 (b) are cross-sectional views corresponding to FIG. 1 (b). FIG. 2 (a) shows a case where the tapered center hole 40 is used as it is as a large-diameter hole. A spherical body 42 having a smaller diameter is used as a guide member, and a positioning recess 44 having a small diameter corresponding to the spherical body 42 is formed in the closing member 14. In this embodiment, the same effect as that of the above embodiment can be obtained.

  FIG. 3B shows a case where the tapered center hole 40 is used as a large-diameter hole portion as it is, and a conical guide protrusion 50 having a similar shape to the center hole 40 is formed in the center hole 40. It protrudes integrally with the opposing surface 32 of the closing member 14 concentrically with the tool axis O so as to protrude inward. The guide protrusion 50 can be provided integrally with the closing member 14, but it may be formed separately and integrally fixed by welding or an adhesive. Also in this embodiment, the same operational effects as those of the above embodiment can be obtained. Further, since the guide member is constituted by the guide protrusion 50 provided integrally with the closing member 14, it is not always necessary to make a significant design change, and can be easily implemented and supplied from the oil hole 20. The fluid can be made to flow substantially uniformly to the outer peripheral side by the guide protrusions 50 fixed in position, and can be discharged more uniformly from the plurality of discharge passages 36, and the fluid supply performance is further improved. Further, as compared with the case where a guide member such as a sphere is incorporated separately, the assembling work when the closing member 14 is integrally fixed to the tap body 12 is facilitated.

  As mentioned above, although the Example of this invention was described in detail based on drawing, these are one Embodiment to the last, This invention is implemented in the aspect which added the various change and improvement based on the knowledge of those skilled in the art. be able to.

  10: Raised tap with oil hole (tap with fluid supply hole) 12: Tap body 14: Closure member 18: Male thread part 20: Oil hole (fluid supply hole) 22: Tip surface 28: Large diameter hole part 30, 42: Sphere (guide member) 32: Opposing surface 34, 44: positioning recess 36: discharge passage 40: center hole (large diameter hole) 50: guide protrusion (guide member) O: tool axis

Claims (4)

A tap main body provided with a male thread portion for processing a female screw in the outer peripheral portion of the tip, and provided with a fluid supply hole so as to pass through the tool axis O and open to the tip surface;
A closing member that is integrally fixed so as to be in close contact with the tip surface of the tap body and closes the tip opening of the fluid supply hole;
At the boundary portion between the tip surface of the tap body and the opposing surface of the closing member that is brought into close contact with the tip surface, a radial direction is formed so as to communicate with the fluid supply hole, and the fluid is supplied from the fluid supply hole. A plurality of discharge passages for discharging fluid to the outer peripheral side;
In a tap with a fluid supply hole having
At the tip opening where the fluid supply hole opens on the tip surface of the tap body, a large-diameter hole that increases in diameter toward the opening end is provided.
The large-diameter hole portion contains a guide member for guiding the fluid supplied through the fluid supply hole to flow toward the outer peripheral side along the inner wall surface of the large-diameter hole portion. Tap with fluid supply hole. The guide member is a sphere configured separately from the tap body and the closing member, and is accommodated in a space surrounded by the large-diameter hole portion and the closing member. The tap with a fluid supply hole according to 1. The opposing surface of the closing member is provided with a positioning recess for positioning the sphere so as to be substantially concentric with the tool axis O when the sphere is pressed by the pressure of the fluid. The tap with a fluid supply hole according to claim 2. The guide member is a guide protrusion having a smaller diameter toward the tip side, which is integrally provided concentrically with the tool axis O so as to protrude inward of the large-diameter hole portion on the opposing surface of the closing member. The tap with a fluid supply hole according to claim 1.

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