Tap

Abstract

To provide a tap in which a coolant is supplied to all tap grooves and chips are discharged to the outside of a prepared hole in any screw forming operation of the prepared hole of a blind hole form and a through hole form.SOLUTION: Since a groove cross-sectional area of a first coolant feed groove 10a for feeding a coolant to a first tap groove 9a (which functions as a chip discharge groove at the time of blind hole formation) is a groove cross-sectional area smaller than the groove cross-sectional area of the coolant feed groove for feeding the coolant to a second tap groove 9b to a fourth tap groove 9d which are chip entry blocking grooves, the coolant fed to the second tap groove 9b to the fourth tap groove 9d flows into a first tap groove 9a together with the chips, moves, and is discharged to the outside from a prepared hole opening at the time of blind hole formation, and the coolant in the first coolant feed groove 10a reaches a tip of the first tap groove 9a to cool the tip at the time of through hole formation.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a tap characterized by a coolant (cutting oil) supply form.

Background Art

[0002] Conventionally, in a tap, as a form of supplying coolant to a tap groove of a threaded portion, a tap provided with a coolant supply groove (outer peripheral groove) in a groove form in which coolant flows on the outer periphery of the shank from the rear end side of the shank toward the tap groove is known. (For example, Patent Document 1)

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] <Drill Tap for Through Hole> In the technology of Patent Document 1 described above, when the pilot hole for forming a thread with a cutting tap is a through hole, a coolant supply groove (side through groove 16 in Patent Document 1) for supplying coolant to each of all the tap grooves is provided corresponding to each of the tap grooves on the outer periphery of the shank (the number of tap grooves and the number of coolant supply grooves are the same). (For example, the tap in FIG. 2 of Patent Document 1 (a form in which four coolant supply grooves are provided for each of the four tap grooves)).

[0005] And its feature is that the four coolant supply grooves have the same groove depth and the same groove width, and coolant is ejected at the same ejection amount and ejection speed from the center (from the center) of each tap groove. By supplying coolant to all the tap grooves (here, described by taking four tap grooves as an example), each of the cutting chips cut out into each of the four tap grooves by the cutting operations of the cutting edges (all the cutting edges) of the four threaded portions is The coolant injected into the tap groove can prevent the chips cut by the coolant from staying in the tap groove, thus preventing the chips from engaging with the thread for a certain period of time. It is forced to be pushed out and discharged below the counterbore. All the cutting edges of the engaged part are cooled by the coolant to reduce the cutting resistance and cutting friction.

[0006] <Counterbore Cutting Tap> Regarding the technology of Patent Document 1 described above, when the counterbore for forming a thread with a cutting tap is a blind hole, a configuration is adopted in which coolant is not supplied to some of the tap grooves, and no coolant supply groove is provided from the tap groove where coolant is not supplied to the rear end of the shank (for example, in the tap shown in FIG. 4 of Patent Document 1, two coolant supply grooves are provided for each of the two tap grooves out of the four tap grooves, and coolant is not supplied to the other two tap grooves).

[0007] During the cutting of the counterbore (blind hole), coolant is injected and supplied to two tap grooves. After the coolant and chips in the coolant supply tap groove (the tap groove where coolant is supplied) flow into the space between the counterbore and the tap tip, they flow into the coolant non - supply tap groove (the tap groove where coolant is not supplied). Then, together with the chips generated by the cutting edge on the coolant non - supply tap groove side, they rise through the coolant non - supply tap groove and are discharged outside the counterbore.

[0008] <Problems of Through - hole Cutting Tap> When the cutting tap for holes described above is used for cutting a blind hole, coolant is injected into all the tap grooves at the same flow rate, the same flow volume, the same groove width, and the same groove depth. As a result, the openings of the coolant and chip discharge grooves formed by the pilot hole being tapped and the tap grooves are covered by the coolant, making it difficult for the coolant and chips to be discharged from the tap grooves (remaining in the tap grooves). This causes problems such as chips biting into the threaded part, poor cooling due to a significantly deteriorated coolant flow, and an increase in frictional resistance.

[0009] <Problems of the cutting tap for blind holes> When the above-described cutting tap for blind holes is used for cutting a through hole (thread formation), coolant is jet-supplied to two coolant supply tap grooves, but the coolant simply flows out below the pilot hole and is discharged (released) together with the chips from the lower opening of the pilot hole and the coolant supply tap grooves. However, no coolant is supplied to the other two non-coolant supply tap grooves, resulting in a drawback that effective cooling of the cutting edge on the non-coolant supply tap groove side, reduction of frictional resistance, and prompt discharge of chips cannot be achieved.

[0010] Therefore, the cutting tap of the invention in Patent Document 1 has the following problems. (A) The cutting tap for through holes is difficult to use for thread formation of blind holes, and the cutting tap for blind holes is difficult to use for thread formation of through holes. (B) In a thread formation environment where thread formation of blind holes and through holes coexists, two types of taps, namely, the cutting tap for through holes and the cutting tap for blind holes, must be prepared, and thread formation must be performed using two cutting devices or by changing the tap while using one cutting device. (C) Since the cutting tap for through holes and the cutting tap for blind holes have the same form except for the coolant supply grooves, there is a possibility of misidentifying the type of tap used.

[0011] Also, the coolant is injected and supplied at the center of the tap groove. However, the state of the wind pressure (air flow) generated in the tap groove outside the pilot hole (in the tap groove that has not yet entered the pilot hole) by the cutting and rotating tap operation is in a state where the wind pressure per cutting edge surface hits the rake face, which is the rising surface on the cutting edge side, toward the cutting edge side. Therefore, the coolant in the tap groove that has not entered the pilot hole has the drawback that a considerable amount is pushed out of the tap groove together with the wind per cutting edge surface, and the amount of coolant supplied to the biting part side during the cutting operation is reduced. And when the pilot hole is a blind hole, it means that the amount of coolant for discharging chips is reduced, which has the drawback that there is a possibility that the chips cannot be discharged sufficiently.

[0012] In the invention of Patent Document 1, the bottom of the coolant supply groove (in Patent Document 1, the side through groove 16) is configured not to reach the bottom of the tap groove 15, but it is appropriate that the bottom is formed to have the same groove depth as the bottom of the tap groove 15 even if it is formed deepest. Therefore, the groove end portion of the coolant supply groove is located at a position far from the tap tip (biting part) (in FIG. 1, the rearmost end position of the threaded part). However, the coolant flowing through the coolant supply groove spreads and scatters in the tap groove with a wide groove width at the groove end portion, and is in a state of decreasing scattering speed where the speed significantly decreases. This state of decreasing scattering speed is such that, especially for some time after the start of cutting the pilot hole (start of thread formation), the tap groove is located in the open space that has not entered the pilot hole between the biting part during the cutting operation and the groove end portion of the coolant supply groove. Therefore, a large amount of the coolant that has become in a state of decreasing scattering speed at the groove end portion scatters into the open space, and the supply amount of the coolant to the biting part during cutting becomes small and the supply momentum becomes weak. Therefore, in the initial stage of cutting the pilot hole (starting thread formation), during the cutting process for some time, there is a high possibility of insufficient chip discharge force, where the coolant flow rate and the chip discharge force, which is the coolant momentum to push the chips below the tap groove (in the direction of thread formation progress of the tap) and extrude the tip of the tap, cannot be obtained. During this period of insufficient chip discharge force, chips may accumulate in the tap groove and jam, and there is a risk of tap groove clogging due to the formation of chip masses, which is a drawback of this kind of tap.

[0013] In view of the above-mentioned drawbacks of the prior art, the present invention provides a tap that supplies coolant to the tap groove through a coolant supply groove communicating with the tap groove. (1) In the thread forming operation of any of the pilot holes in the form of a blind hole or a through hole, coolant is supplied to all the tap grooves (including the grooves of the rolled tap), and when chips are generated, the chips are discharged out of the pilot hole. The purpose is to provide a tap (including a cutting tap and a rolled tap). (2) Also, the purpose is to provide a tap (including a cutting tap and a rolled tap) that can supply a larger amount of coolant to the side of the engaging part during the thread forming operation. (3) Also, the purpose is to provide a tap (including a cutting tap and a rolled tap) with high torsional strength. (4) Also, the purpose is to provide a tap (including a cutting tap and a rolled tap) that can ensure the supply amount or the impact force per unit of coolant to the engaging part from the start of thread formation in the pilot hole.

Means for Solving the Problem

[0014] To achieve the above object, the present invention has the following configuration. [Invention 1] A tap body having a plurality of thread parts including an engaging part and a complete thread part, and a shank part communicating with the thread part. A tap groove formed between adjacent thread parts. A coolant supply groove provided on the outer periphery of the shank part, which supplies coolant from the rear end side of the shank part to all the tap grooves. at least the same number as the number of said tapping grooves for supplying to each of And is provided with a coolant supply groove. In the case where the pilot hole for forming the female thread is a blind hole, A part of the tap groove functions as a chip intrusion prevention groove, The chip entry prevention groove releases chips into the pilot hole space, which is the space of the pilot hole that spreads forward of the threaded portion, depending on the amount and / or force of the coolant supplied, and prevents the chips from entering the pilot hole space. the chip entry prevention The groove functions as a groove that does not allow entry into the groove. The tap grooves other than the chip entry prevention grooves function as chip discharge grooves that move within the grooves so that the coolant containing the chips discharged from the chip entry prevention grooves into the pilot hole space is discharged to the outside from a pilot hole opening that is an opening of the pilot hole, a chip discharge groove connecting coolant supply groove, which is a coolant supply groove that supplies coolant to the chip discharge groove among the coolant supply grooves, has a coolant supply form that cannot prevent coolant containing chips from entering the chip discharge groove and being discharged to the outside through the pilot hole opening, In the case where the pilot hole is a through hole, The coolant supplied from the chip discharge groove connecting coolant supply groove flows through the chip discharge groove and reaches the tip side of the threaded portion to cool the tip side. part a tap having a through coolant supply hole extending from the rear end side of the shank portion to the front end side of the threaded portion for supplying coolant from the rear end side of the shank portion and discharging it from the front end side of the threaded portion. [Invention 2] A tap body having a plurality of threaded portions each having a chamfer portion and a complete thread portion, and a shank portion connected to the threaded portions; a tap groove formed between adjacent threaded portions; A coolant supply groove is provided on the outer periphery of the shank portion for supplying coolant from a rear end side of the shank portion to all or some of the tap grooves, The groove form of all or part of the coolant supply groove is a non-through groove form in which the groove extends to a position of at least approximately 1 / 3 of the tap groove within the range of the complete thread portion and has a groove end point (82), or a through groove form without the groove end point (82) penetrating the tap groove. The tap is characterized by this. [Invention 3] A tap body having a plurality of thread portions including a biting portion and a complete thread portion, and a shank portion communicating with the thread portions. A tap groove formed between adjacent thread portions. A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or part of the tap grooves. The form of all or part of the tap groove is a tap groove form having a shallow tap groove portion in which the form of the groove extends from the shank side toward the tap tip and is a shallow groove form, and a deep tap groove portion located on the tap tip side of the shallow tap groove portion and extending toward the tap tip and having a groove form deeper than the shallow tap groove portion. The length of the shallow tap groove portion is a length form extending to a position of at least approximately 1 / 3 of the tap groove within the range of the complete thread portion. The tap is characterized by this. [Invention 4] The shallow tap groove portion is in a form in which the coolant supply groove is formed in a through form. The tap according to Invention 3 is characterized by this. [Invention 5] A tap body having a plurality of thread portions including a biting portion and a complete thread portion, and a shank portion communicating with the thread portions. A tap groove formed between adjacent thread portions. A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or part of the tap grooves. In all or part of the axial direction of the tap groove, a raised portion is provided which is formed in a rising form from the groove bottom of the tap groove and communicates with the shank portion and is within the range of the complete thread portion toward the tap tip side. The tap is characterized by this. [Invention 6] The raised portion is in a form in which the coolant supply groove is formed, and the tap according to the invention 5 described above is characterized in this regard. [Invention 7] A tap body having a plurality of thread portions having a gripping portion and a full thread portion, and a shank portion communicating with the thread portion. A tap groove formed between adjacent thread portions. A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or some of the tap grooves. In all or part of the tap groove, a partition wall is provided in a form that does not contact the female thread formed in the pilot hole and is formed in a form that communicates with the shank portion and is within the range of the full thread portion toward the tap tip side. The tap is characterized in that the tap groove 9d is divided into two grooves by the partition wall, and a back surface side groove and a cutting surface side groove are formed. [Invention 8] The tap according to the invention 7 described above, wherein the coolant supply groove communicates with the back surface side groove or the cutting surface side groove. [Invention 9] A tap body having a plurality of thread portions having a gripping portion and a full thread portion, and a shank portion communicating with the thread portion. A tap groove formed between adjacent thread portions. A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or some of the tap grooves. When the pilot hole for forming the female thread is a stop hole. A part of the tap groove functions as a chip entry prevention groove. The chip entry prevention groove is in a form in which the coolant supply groove communicates therewith, and by the amount and momentum of the supplied coolant or either one thereof, chips are discharged into the pilot hole space, which is the space of the pilot hole that spreads toward the tip of the thread portion, and the chip entry prevention groove functions as a groove that does not allow the chips to enter the chip entry prevention groove. The tap grooves other than the chip entry prevention grooves function as chip discharge grooves that move within the grooves so that coolant containing chips discharged from the chip entry prevention grooves into the pilot hole space is discharged to the outside from a pilot hole opening that is an opening of the pilot hole, The tap is characterized in that the groove width of the chip entry prevention groove is narrower than the groove width of the chip discharge groove. [Invention 10] The tap according to invention 9, characterized in that in the chip entry prevention groove, the groove form of the coolant supply groove communicating with the chip entry prevention groove is a non-through groove form in which the groove extends to a position approximately 1 / 3 or more of the tap groove in the range of the complete thread portion and has a groove end point (82), or a through groove form in which the groove does not have the groove end point (82) and passes through the tap groove. [Invention 11] The groove form of the chip intrusion prevention groove has a shallow tap groove portion which is a shallow groove form extending from the shank side toward the tip of the tap, and a deep tap groove portion which is a groove form deeper than the shallow tap groove portion and is located on the tap tip side than the shallow tap groove portion, The tap according to claim 9, characterized in that the coolant supply groove connected to the chip entry prevention groove has a shallow groove penetrating form that penetrates the shallow tap groove portion and is configured to release coolant to the deep tap groove portion. Effect of the Invention

[0015] [Effects of Invention 1] In the case where the pilot hole forming the female thread is a blind hole, the chip entry prevention groove realizes a form in which chips do not enter the chip entry prevention groove by the coolant supplied thereto, and the chip discharge groove is a coolant supply groove that supplies coolant to the chip discharge groove, and the chip discharge groove connecting coolant supply groove has a coolant supply form in which the coolant containing chips cannot be prevented from entering the chip discharge groove and being discharged to the outside from the pilot hole opening, and therefore realizes a form in which the coolant containing chips released from the chip entry prevention groove into the pilot hole space moves within the groove so as to be discharged to the outside from the pilot hole opening, which is the opening of the pilot hole, In the case where the pilot hole is a through hole, the coolant supplied from the chip discharge groove communication coolant supply groove flows through the chip discharge groove, reaches the tip side of the threaded portion, and cools the tip side. Therefore, whether the thread is formed in a blind hole or a through hole, this has the advantageous effect of realizing a tap that allows coolant to reach and cool all of the tap grooves and all of the cutting edges of the chamfer at their tips. Since only one type of tap can be used, which is a tap for both pilot holes, there is no need to manage taps for blind holes and taps for through holes separately, and mistakes such as using a through hole tap for a blind hole can be prevented, thereby simplifying the management of taps. [Effects of Invention 2] In tap grooves in which the coolant supply groove extends to a position approximately 1 / 3 or more of the tap groove in the range of the complete thread portion and has a groove end point (82), or in which the coolant supply groove is a through groove that does not have a groove end point (82) that penetrates the tap groove, the coolant reaches a position approximately 1 / 3 or more of the tap groove in the range of the complete thread portion (a position closer to the chamfer) and splashes at the groove end point (82), thereby realizing a configuration in which more coolant reaches the tip side of the tap groove (the chamfer). Alternatively, in a through groove configuration in which the coolant supply groove extends to and penetrates the tip of the tap groove, a configuration in which more coolant reaches the tip side of the tap groove (the chamfer) is realized. [Effects of Invention 3] Providing a shallow morphological part in the tap groove means that the wall thickness increases accordingly, enhancing the torsional strength of the tap and realizing a tap with high durability that is not easily damaged. [Effect of Invention 4] It has the same effect as the above Invention 3. Since the coolant supply groove is formed in a penetrating form in the shallow morphological part, and the groove depth of the coolant supply groove part formed in the shallow morphological part can be made into a deep groove form, the coolant supplied by the coolant supply groove can be released more vigorously and in a larger amount by the deep tap groove part. Therefore, it has the effect of realizing a form in which more coolant reaches the tip side (thread engagement part) of the tap groove more vigorously. [Effect of Invention 5] It has a tap groove provided with a raised part formed in a form that rises from the groove bottom and connects to the shank part in a rising form and is within the range of the complete thread part toward the tap tip side. Therefore, it has the effect that the torsional strength is enhanced by the wall thickness of the raised part. [Effect of Invention 6] It has the same effect as the above Invention 5. Since the coolant supply groove is formed in the raised part, it has the effect of being able to deliver more coolant vigorously to the tap center side. [Effect of Invention 7] In a tap having a coolant supply groove, a partition wall is provided which connects to the shank part and is formed within the range of the complete thread part toward the tap tip side. By this partition wall, a back surface side groove and a cutting surface side groove are formed. Therefore, the coolant supply groove can be connected to the back surface side groove or the cutting surface side groove. Since the back surface side groove or the cutting surface side groove has a narrow groove form, it is possible to reduce the scattering of the coolant released from the coolant supply groove and increase the amount of coolant reaching the tap tip. Also, it has the effect of realizing an enhancement of the torsional strength by the partition wall. [Effect of Invention 8] It has the same effect as the above Invention 7. [Effect of Invention 9] It has the same effects as the above-mentioned Invention 1, and since the groove width of the chip entry prevention groove is narrower than that of the chip discharge groove, the curling of the chip can be reduced, and the breakage of the chip can be accelerated, thus promoting the formation of short chips. Also, the amount of coolant flowing through the chip entry prevention groove is suppressed in terms of the amount of scattering and the momentum weakening, so that more coolant can reach the tip of the tap. It has the function and effect of achieving this. [Effects of Invention 10] It has the same effects as the above-mentioned Invention 9, and in the chip entry prevention groove, the coolant supply groove is in a non-through groove form where the groove extends to a position of at least 1 / 3 or more of the tap groove in the range of the complete thread part and has a groove end point (82), or in the tap groove in a through groove form without a groove end point (82) penetrating the tap groove, the coolant reaches a position of at least 1 / 3 or more of the tap groove in the range of the complete thread part (a position closer to the biting part) and scatters at the groove end point (82), so that a form is realized in which more coolant reaches the tip side (biting part) of the tap groove. Or, in the through groove form where the coolant supply groove reaches and penetrates to the tip of the tap groove, a form is realized in which more coolant reaches the tip side (biting part) of the tap groove. It has the function and effect of achieving this. [Effects of Invention 11] It has the same effects as the above-mentioned Invention 9, and the fact that a shallow form part is provided in the tap groove means that the wall thickness increases accordingly, so the torsional strength of the tap is enhanced, realizing a durable tap that is difficult to break. Since the coolant supply groove is formed in a through form in the shallow form part, and also, since the groove depth of the coolant supply groove part formed in the shallow form part can be made into a deep groove form, the coolant supplied by the coolant supply groove is realized to be released more powerfully in the deep tap groove part. Therefore, a form is realized in which more coolant reaches the tip side (biting part) of the tap groove powerfully. It has the function and effect of achieving this.

Brief Description of the Drawings

[0016]

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[0017] Hereinafter, examples of the best mode for carrying out the present invention will be described. However, it is not intended that the present invention be limited to these examples. In addition, in the description of the following examples, the same components as those in the above-mentioned examples will be designated by the same reference numerals, and duplicated descriptions will be omitted. EXAMPLES

[0018] In the first embodiment of the present invention shown in FIG. 1, a cutting tap 1 has the following configuration. [Definition] (1) The term "chip entry prevention groove" refers to a tap groove that, when the pilot hole forming the female thread is a blind hole, functions as a groove that releases (pushes) chips into the pilot hole space, which is the space of the pilot hole that extends beyond the threaded portion, depending on the amount and / or force of coolant supplied, thereby preventing the chips from entering the chip entry prevention groove. (2) "Chip discharge groove (a form that functions as a groove that does not allow chips to enter)" refers to a tap groove that functions as a chip discharge groove that moves within the groove so that, when the pilot hole forming the female thread is a blind hole, the coolant containing the chips released from the chip entry prevention groove into the pilot hole space is discharged to the outside from the pilot hole opening, which is the opening of the pilot hole. (3) The "chip discharge groove communication coolant supply groove" is a coolant supply groove that communicates with the chip discharge groove and supplies coolant to the chip discharge groove. When the counterbore is a through hole, the coolant supplied from the chip discharge groove communication coolant supply groove flows through the chip discharge groove to reach the tip side of the thread portion and cools the tip side, realizing a form of cooling. When the counterbore is a blind hole, it is a groove of a coolant supply form (for example, a coolant supply form of the amount and momentum of the coolant or either one of the coolant supply forms) that cannot prevent the entry movement of the coolant entraining the chips discharged from the chip entry prevention groove into the chip discharge groove and the discharge from the counterbore opening to the outside. This is the same in the following embodiments.

[0019] A tap body 7 having a plurality of thread portions 4 (a first thread portion 4a, a second thread portion 4b, a third thread portion 4c, a fourth thread portion 4d) composed of a biting portion 2 for cutting and forming an internal thread and a complete thread portion 3, a shank portion 5, and a square portion 6 provided at the tip (rear end) of the shank portion 5. The number of thread portions 4 for cutting and forming an internal thread in the counterbore A may be two, three, five, or more. Tap grooves formed between adjacent thread portions 4 (here, a first tap groove 9a (chip discharge groove) is formed between the first thread portion 4a and the second thread portion 4b, a second tap groove 9b (chip entry prevention groove) is formed between the second thread portion 4b and the third thread portion 4c, a third tap groove 9c (chip entry prevention groove) is formed between the third thread portion 4c and the fourth thread portion 4d, and a fourth tap groove 9d (chip entry prevention groove) is formed between the fourth thread portion 4d and the first thread portion 4a). Coolant supply grooves (there are those supplied in liquid form, those supplied in mist form, etc.) provided on the outer periphery of the shank portion 5 for supplying coolant to each of all the tap grooves from the rear end side of the shank portion 5. The number of coolant supply grooves is at least the same as the number of tap grooves. Here, a first coolant supply groove 10a (chip discharge groove communication coolant supply groove) for supplying coolant to the first tap groove 9a (chip discharge groove) is provided, a second coolant supply groove 10b for supplying coolant to the second tap groove 9b (chip entry prevention groove) is provided, a third coolant supply groove 10c for supplying coolant to the third tap groove 9c (chip entry prevention groove) is provided, and a fourth coolant supply groove 10d for supplying coolant to the fourth tap groove 9d (chip entry prevention groove) is provided. At least one of the coolant supply grooves (here, one of the first coolant supply grooves 10a, but it may also be a plurality) is a chip discharge groove communication coolant supply groove (here, the first coolant supply groove 10a with different groove depths) having a different groove width, a different groove depth, or different groove widths and different groove depths from the other coolant supply grooves (here, the second coolant supply groove 10b, the third coolant supply groove 10c, and the fourth coolant supply groove 10d). The groove cross-sectional area of the first coolant supply groove 10a (chip discharge groove communication coolant supply groove) is smaller than the groove cross-sectional areas of the other coolant supply grooves (except for the case where a through coolant supply hole provided in the form of a through hole is provided from the rear end side of the shank portion 5 to the tip side of the threaded portion 4 for supplying coolant from the rear end side of the shank 5 and discharging it from the tip side of the threaded portion 4).

[0020] A coolant reservoir 11 in the form of a hole is formed at the rear end of the shank portion 5, and coolant introduction grooves for introducing coolant from the coolant reservoir 11 into each of the coolant supply grooves are provided (here, a first coolant introduction groove 12a for supplying the first coolant supply groove 10a is provided, a second coolant introduction groove 12b for supplying the second coolant supply groove 10b is provided, a third coolant introduction groove 12c for supplying the third coolant supply groove 10c is provided, and a fourth coolant introduction groove 12d for supplying the fourth coolant supply groove 10d is provided.). The groove cross-sectional area of the coolant introduction groove 12a of the first coolant supply groove 10a (the chip discharge groove connection coolant supply groove) is a smaller cross-sectional area than the groove cross-sectional areas of the coolant introduction grooves of the other coolant supply grooves.

[0021] The first coolant supply groove 10a, which is the chip discharge groove connection coolant supply groove, is also a small coolant supply groove with a smaller injection supply amount of coolant than the other coolant supply grooves. The groove widths of all the coolant supply grooves are the same, and the groove depths of the other coolant supply grooves (the second coolant supply groove 10b to the fourth coolant supply groove 10d) are the same and are deeper than the groove depth of the first coolant supply groove 10a. All the coolant supply grooves and all the coolant introduction grooves are located on the approximate center line B of each tap groove.

[0022] The "position provided on the approximate center line B of each tap groove" includes any form in which the coolant supply groove reaches the tap groove, the form in which the coolant supply groove does not reach the tap groove, and the form in which coolant is injected and supplied to the tap groove. The same applies to the following inventions.

[0023] A form in which a through coolant supply hole (center through hole) provided in a through hole form from the rear end side of the shank portion 5 to the tip side of the threaded portion 4 for supplying coolant from the rear end side of the shank 5 and discharging it from the tip side of the threaded portion 4 is not provided means excluding from this embodiment a form in which a through coolant supply hole (center through hole) provided in a through hole form from the rear end side of the shank portion 5 to the tip side of the threaded portion 4 is provided. The same applies to the taps in the following embodiments. Also, the cutting edge portion of the biting portion at the portion where the tap groove is a chip entry preventing groove is preferably in a point tap blade form or a point tap groove form in which the chips are discharged in the same direction as the traveling direction. The same applies to the cutting taps in the following embodiments.

[0024] The following effects are achieved. (1) In the cutting thread formation of the pilot hole A as a through hole, coolant is supplied to all the tap grooves (tap grooves 9a to 9d), and the coolant supply amount from the chip discharge groove communication coolant supply groove (the first coolant supply groove 10a) is less than the supply amounts from the other coolant supply grooves (the second coolant supply groove 10b to the fourth coolant supply groove 10d). (This is because the groove cross-sectional area of the chip discharge groove communication coolant supply groove is smaller than the groove cross-sectional areas of the other coolant supply grooves.) Even in the tap groove that receives the jet supply from such a chip discharge groove communication coolant supply groove, the cutting edge is cooled by the supplied coolant, the frictional resistance is reduced, and the cut chips are pushed downward by the coolant and quickly discharged from the lower opening of the pilot hole A. (2) In the cutting thread formation of the pilot hole A as a blind hole, the supply amount of the coolant from the chip discharge groove communication coolant supply groove (the first coolant supply groove 10a) to the tap groove 9a (chip discharge groove) is smaller than the supply amounts of the coolant from the other coolant supply grooves (the second coolant supply groove 10b to the fourth coolant supply groove 10d) to the tap grooves 9b to 9d (chip entry preventing grooves) respectively. On the other hand, the amount of coolant supplied to the other coolant supply grooves is larger than the amount of coolant supplied from the chip discharge groove communication coolant supply groove to the tap groove (chip discharge groove). Therefore, in the thread formation of the blind hole, the coolant (including chips) in other coolant supply grooves (the second coolant supply groove 10b to the fourth coolant supply groove 10d) pushes up and discharges the coolant (including chips) in the chip discharge groove connecting coolant supply groove (the first coolant supply groove 10a), or changes the flow direction to the side with less influence of the coolant in the first coolant supply groove 10a (chip discharge groove connecting coolant supply groove), and then directly rises through the tapping groove 9a (chip discharge groove) to discharge the coolant and chips from the upper opening of the bottom hole A (accurately, the tapping hole formed by the bottom hole 10a (represented by a two-dot chain line) and the tapping groove 9a). This has the effect of achieving the discharge of coolant and chips. That is, a cutting tap that can be used without problems in the use of a blind hole is realized. (3) From (1) and (2) above, a cutting tap (hereinafter also referred to as a "tap compatible with both bottom holes") that realizes a cooling effect, a friction reduction effect, and a chip discharge effect in both the use of a through hole and the use of a blind hole is realized. For example, when a combination of forming the same-diameter thread in a blind hole and forming the same-diameter thread in a through hole occurs, it can be handled with one type of the same-diameter cutting tap. For example, since the cutting tap can be only one type of the tap compatible with both bottom holes, there is no need to manage it separately from the tap for blind holes and the tap for through holes. Also, mistakes such as using the tap for through holes in blind holes can be avoided, and the management of the taps can be simplified.

Embodiment

[0025] In the second embodiment of the present invention shown in FIG. 2, the main difference from the first embodiment is that a cutting tap 20 is formed with the first coolant supply groove as the first coolant supply groove 21a and the first coolant introduction groove as the first coolant introduction groove 22a. The first coolant supply groove 21a has a groove opening position closer to the second thread portion 4b side (the position on the rake face 14b side) in the right side view, a groove depth substantially the same as that of other coolant supply grooves (the second coolant supply groove 10b to the fourth coolant supply groove 10d), and a groove width narrower than that of the other coolant supply grooves. Further, taking the portion of the tapping groove within the range of the threaded portion 4 as the threaded portion range groove portion (the tapping groove portion within the range of the complete threaded portion 3 as the complete threaded portion range groove portion), the first coolant supply groove 21a extends in a groove depth form that engraves (forms) a groove at the groove bottom of the tapping groove located in the threaded portion range groove portion through the first tapping groove 9a (chip discharge groove) with which it communicates. The groove end point 82 is positioned such that the coolant flowing through the coolant supply groove is scattered and the coolant hits the biting portion 2 well when the progress of the coolant is hindered or the progress direction is changed. The length of the first coolant supply groove 21a (= the length up to the groove end point 82) is preferably 1 / 3 or more of the length of the threaded portion range groove portion (the portion of the tapping groove within the range of the threaded portion 4), more preferably half or more of the length, still more preferably 2 / 3 or more of the length, and most preferably the length at which the scattered coolant reaches the groove end point 82 and hits the biting portion 2 well. In the right side view, the first coolant introduction groove 22a has a groove opening positioned closer to the second threaded portion 4b side (a position close to the rake face 14b), and its groove width is substantially the same as that of the first coolant introduction groove 22a. The groove widths of the second to fourth coolant introduction grooves 12b to 12d that communicate with the other coolant supply grooves (the second to fourth coolant supply grooves 10b to 10d) are substantially the same as the groove widths of the other coolant supply grooves. The first coolant supply groove 21a is a chip discharge groove communication coolant supply groove, a small amount coolant supply groove, and a differently arranged coolant supply groove (an arrangement form in which the arrangement position in the tapping groove is different from that of the other coolant supply grooves).

[0026] In the case of use in a blind hole, the first tapping groove 9a that receives coolant supply from the first coolant supply groove 21a functions as a chip discharge groove. In that case, since the coolant flowing in the first tap groove 9a (chip discharge groove) is supplied from the side of the rake face 14b, the amount and momentum of the coolant near the back surface 15a become weak. As a result, the coolant and chips in the other coolant supply grooves (the second coolant supply groove 10b to the fourth coolant supply groove 10d) easily flow and move toward the back surface 15a side of the first tap groove 9a (chip discharge groove), and are discharged.

Embodiment

[0027] In the third embodiment of the present invention shown in FIG. 3, the main difference from the second embodiment is that a cutting tap 25 is formed in a form without providing the square portion 6. The tap body 26 is formed by the thread portion 4 and the shank 5. The groove depth can be made deeper than that of the coolant supply groove passing through the center of the side of the square portion, which means that the groove depth can be made shallower, and that means that the strength of the shank can be made stronger. The holder for gripping the shank 5 is preferably a shrink-fit holder in which no gap is generated in the side wall of the gripping portion.

Embodiment

[0028] In the fourth embodiment of the present invention shown in FIG. 4, the main difference from the first embodiment is that a cutting tap 30 is formed in which the first coolant introduction groove communicating with the first coolant supply groove 10a is a first coolant introduction groove 29 having a groove width narrower than the groove width of the first coolant supply groove 10a (the groove depth is the same). Compared with the other coolant supply grooves, the flow velocity of the coolant in the first coolant supply groove 10a can be slowed down and the flow rate can also be reduced.

Embodiment

[0029] In Example 5 of the present invention shown in FIG. 5, the main difference from Example 3 is that a first coolant supply groove for supplying coolant to the first tap groove 9a (chip discharge groove) is a first coolant supply groove 33a (chip discharge groove connection coolant supply groove, small amount coolant supply groove) having a groove width wider than the groove width of the first coolant introduction groove 22a (the groove depth is the same), and a cutting tap 34 is formed. Compared with other coolant supply grooves, the flow rate of the coolant in the first coolant supply groove 33a can be reduced. The first coolant supply groove 33a is a chip discharge groove connection coolant supply groove, a small amount coolant supply groove, and also a differently arranged coolant supply groove (a layout form in which the arrangement position in the tap groove is different from that of other coolant supply grooves).

Example

[0030] In Example 6 of the present invention shown in FIG. 6, the main difference from Example 5 is that a first coolant supply groove for supplying coolant to the first tap groove 9a (chip discharge groove) is a first coolant supply groove 36a (chip discharge groove connection coolant supply groove, small amount coolant supply groove, differently arranged coolant supply groove) having a groove width narrower than the groove width of the first coolant introduction groove 22a, and a cutting tap 37 is formed.

Example

[0031] In Example 7 of the present invention shown in FIG. 7, the main difference from Example 6 is that a first coolant supply groove and a first coolant introduction groove for supplying coolant to the first tap groove 9a (chip discharge groove) are provided at positions closer to the first thread portion 4a side (the back surface 15a side) in the right side view, and a cutting tap 42 is formed with a first coolant supply groove 40a (chip discharge groove connection coolant supply groove, small amount coolant supply groove, differently arranged coolant supply groove) and a first coolant introduction groove 41a. That is, the arrangement position of the first coolant supply groove 40a is a position closer to the back surface 15a side of the first thread portion 4a that cuts first. It is a position away from the rake face 14b of the second thread portion 4b, which is the groove side wall surface that receives the wind pressure accompanying the cutting rotation. Since the first thread portion 40a serves as a wind shield, it reduces the scattering of the coolant due to the wind pressure and delivers a large amount to the tip of the tap.

[0032] It has the following effects. (1) During the rotary cutting operation of the cutting tap 1, in the tap groove portion outside the pilot hole, the air pressure (wind pressure) generated by the rotation directly hits the rake face 14b of the second thread portion 4b following the first thread portion 4a and easily flows out of the tap groove. Therefore, the coolant closer to the rake face 14b is pushed out of the tap groove and flows out by the wind pressure. On the other hand, since the back surface 15a of the leading first thread portion 4a is a place where the wind pressure does not directly act (is not applied), the coolant injected and supplied from the first coolant supply groove 40a (abnormally arranged coolant supply groove) provided at a position closer to the back surface 15a side of the leading first thread portion 4a is not directly hit by the wind pressure generated by the rotation of the tap. Thus, it has the effect of supplying more coolant into the pilot hole and reaching the tip of the tap. (2) Due to (1) above, since more coolant can be supplied to the pilot hole, the first coolant supply groove 40a (abnormally arranged coolant supply groove) can be formed in a shallower groove shape than other coolant supply grooves. This enables a reduction in the coolant supply amount or a slower injection supply flow rate of the coolant, and thus has this effect. (3) Due to (2) above, the abnormally arranged coolant supply groove can be made shallower. The formation of a shallow groove can strengthen and toughen the strength of the shank (the thicker the part of the shank without the groove (solid core part) as the groove is shallower), and thus has this effect.

Example

[0033] In Example 8 of the present invention shown in FIG. 8, the main difference from Example 7 is that a cutting tap 44 is formed in such a position that the arrangement positions of the second to fourth coolant supply grooves, which are other coolant supply grooves, are in a position form closer to the back side of the land in the right side view.

[0034] Specifically, The second coolant supply groove 45b (other coolant supply groove) is in a position form closer to the back surface 15b side of the second thread portion 4b in the right side view. The groove depth is formed at the groove bottom of the second tap groove 9b (chip entry prevention groove) so that the groove penetrates to the tap tip. Also, the second coolant introduction groove 46b is in a form shifted toward the second thread portion 4b side. The third coolant supply groove 45c (other coolant supply groove) is in a position form closer to the back surface 15c side of the third thread portion 4c in the right side view. The groove depth is formed at the groove bottom of the third tap groove 9c (chip entry prevention groove) so that the groove penetrates to the tap tip. Also, the third coolant introduction groove 46c is in a form shifted toward the second thread portion 4c side. The fourth coolant supply groove 45d (other coolant supply groove) is in a position form closer to the back surface 15d side of the fourth thread portion 4d in the right side view. The groove depth is formed at the groove bottom of the second tap groove so that the groove penetrates to the tap tip. Also, the fourth coolant introduction groove 46d is in a form shifted toward the fourth thread portion 4d side in the right side view.

[0035] Each coolant supplied from the second coolant supply groove 45b to the fourth coolant supply groove 45, which are other coolant supply grooves, is in a form closer to the center line 3 than the back side of the preceding thread portion. Therefore, each coolant is not exposed to a direct wind pressure by the preceding thread portion, so the amount of coolant scattered from the tap groove decreases, and thus the amount of coolant reaching the tip of the tap increases. When the amount of coolant reaching the tap tip is large, it is possible to shallower the groove depth of all or part of the other coolant supply grooves (for example, the groove portion in the full thread portion range), which increases the strength of the shank 5.

[0036] The formation positions of the second coolant supply groove 45b, the third coolant supply groove 45c, and the fourth coolant supply groove 45d may be in a form where they are located on the substantially central position line B, or may be in a form where they are formed closer to the rake face.

Embodiment

[0037] In Embodiment 9 of the present invention shown in FIG. 9, the cutting tap 50 has the following configuration. A tap body 7 having a threading portion 4 composed of a biting portion 2 for cutting a female thread in the pilot hole A and a complete thread portion 3, a shank portion 5, and a square portion 6 provided at the tip of the shank portion 5 (there is also a form without the square portion 6), A first thread portion 4a, a second thread portion 4b, a third thread portion 4c, a fourth thread portion 4d (the number of thread portions may be two, three, five, or more), Tap grooves formed between adjacent thread portions 4 (here, a first tap groove 9a (chip discharge groove) is formed between the first thread portion 4a and the second thread portion 4b, a second tap groove 9b (chip entry prevention groove) is formed between the second thread portion 4b and the third thread portion 4c, a third tap groove 9c (chip entry prevention groove) is formed between the third thread portion 4c and the fourth thread portion 4d, and a fourth tap groove 9d (chip entry prevention groove) is formed between the fourth thread portion 4d and the first thread portion 4a).), Coolant supply grooves at least the same number as the number of tap grooves for supplying coolant (which may be supplied in a liquid form, a mist form, etc.) provided on the outer periphery of the shank portion 5 from the rear end side of the shank portion 5 to each of all the tap grooves (here, a first coolant supply groove 51a for supplying coolant to the first tap groove 9a (chip discharge groove) is provided, a second coolant supply groove 51b for supplying coolant to the second tap groove 9b (chip entry prevention groove) is provided, a third coolant supply groove 51c for supplying coolant to the third tap groove 9c (chip entry prevention groove) is provided, and a fourth coolant supply groove 21d for supplying coolant to the fourth tap groove 9d (chip entry prevention groove) is provided.).), At the rear end of the shank portion 5, a coolant reservoir 11 in the form of a hole is formed, and coolant introduction grooves for introducing coolant from the coolant reservoir 11 into each of the coolant supply grooves are provided (here, a first coolant introduction groove 52a for supplying the first coolant supply groove 51a is provided, a second coolant introduction groove 52b for supplying the second coolant supply groove 51b is provided, a third coolant introduction groove 52c for supplying the third coolant supply groove 51c is provided, and a fourth coolant introduction groove 52d for supplying the fourth coolant supply groove 51d is provided.). In the right side view, the first coolant supply groove 51a and the first coolant introduction groove 52a are positioned closer to the back surface 15a side of the first threaded portion 4a of the first tap groove 9a (chip discharge groove). In the right side view, the second coolant supply groove 51b and the second coolant introduction groove 52b are positioned closer to the back surface 15b side of the second threaded portion 4b of the second tap groove 9b (chip entry prevention groove). In the right side view, the third coolant supply groove 51c and the third coolant introduction groove 52c are positioned closer to the back surface 15c side of the third threaded portion 4c of the third tap groove 9c (chip entry prevention groove). In the right side view, the fourth coolant supply groove 51d and the fourth coolant introduction groove 52d are positioned closer to the back surface 15d side of the fourth threaded portion 4d of the fourth tap groove 9d (chip entry prevention groove). The cutting tap 50 is configured not to have a through coolant supply hole provided in a through hole form from the rear end side of the shank portion 5 to the tip side of the threaded portion 4 for supplying coolant from the rear end side of the shank 5 and discharging it from the tip side of the threaded portion 4, that is, it is a tap in a form that excludes the through coolant supply hole from the configuration. The form in which a through coolant supply hole (center through hole) provided in a through hole form from the rear end side of the shank portion 5 to the tip side of the threaded portion 4 for supplying coolant from the rear end side of the shank 5 and discharging it from the tip side of the threaded portion 4 is not provided means excluding from this embodiment the form in which a through coolant supply hole (center through hole) provided in a through hole form from the rear end side of the shank portion 5 to the tip side of the threaded portion 4 is provided. The same applies to other embodiments.

[0038] It has the following effects. The cutting tap 50 is an optimal tap for use in a through hole or for exclusive use in a through hole. The state of the wind pressure (air flow) generated in the tap groove outside the pilot hole A (in the tap groove that has not yet entered the pilot hole) by the tap operation of cutting rotation is in a state where the wind pressure per cutting edge surface hits the rake surface, which is the rising surface on the cutting edge side, toward the cutting edge side. Therefore, a considerable amount of the coolant in the tap groove that has not entered the pilot hole is pushed out of the tap groove together with the wind per cutting edge surface. In particular, the coolant on the rake surface side is pushed out of the tap groove by the wind pressure caused by the cutting rotation of the tap, so that the amount of coolant reaching the tip of the tap is reduced. Since all the coolant supply grooves of the cutting tap 50 are provided (arranged) at positions closer to the back surface side of the threaded portion that precedes in the cutting operation, the threaded portion prevents or reduces the influence of the wind pressure caused by the cutting rotation of the tap. Thus, it has the effect of reducing the scattering of the coolant outside the tap groove due to the wind pressure and increasing the amount of coolant reaching the tip of the tap.

[0039] The first coolant supply groove 51a, the second coolant supply groove 51b, the third coolant supply groove 51c, and the fourth coolant supply groove 51d extend in a groove depth form that forms (cuts) a groove at the groove bottom of the tap groove located in the threaded portion 4 through the communicating tap groove, and the groove end point 82 is a position where the coolant flowing through the coolant supply groove is prevented from scattering or its direction is changed so that the coolant hits well on the biting portion 2 by the progress of the coolant being hindered or the progress direction being changed. The position of the groove end point 82 (= the length of the coolant supply groove) is at a position of 1 / 3 or more of the threaded portion range groove part (the tap groove part within the range of the threaded portion 4), preferably at a position of 1 / 2 or more, more preferably at a position of 2 / 3 or more, and most preferably at a position where the coolant scattered upon reaching the groove end point 82 hits well (reaches well) the biting part 2. It is preferably set as the length of the coolant supply groove that realizes this position.

[0040] The formation positions of the first coolant supply groove 51a, the second coolant supply groove 51b, the third coolant supply groove 51c, and the fourth coolant supply groove 51d may be in a form where they are located on the substantially central position line B, or may be in a form formed closer to the rake face.

Example

[0041] In Example 10 of the present invention shown in FIG. 10, the main difference from Example 9 is that a coolant supply groove for supplying coolant to the first tap groove 9a (chip discharge groove) is not provided (therefore, no coolant introduction groove is provided in the square portion 6), and a cutting tap 55 is formed. The cutting tap 55 is an optimal tap for use in a blind hole or for exclusive use in a blind hole. In the cutting thread formation of a blind hole, the coolant and chips in the second tap groove 9b (chip entry prevention groove) to the fourth tap groove 9d (chip entry prevention groove) are discharged from the tip of the tap into the pilot hole, flow into the first tap groove 9a (chip discharge groove), rise (move), and are discharged out from the pilot hole opening.

Example

[0042] In Example 11 of the present invention shown in FIG. 11, the cutting tap 65 has the following configuration. A tap body 7 having a biting part 2 for cutting and forming an internal thread, a threaded part 4 composed of a full thread part 3, a shank part 5, and a square part 6 provided at the tip of the shank part 5 (there is also a form without the square part 6), a first threaded part 4a, a second threaded part 4b, a third threaded part 4c, and a fourth threaded part 4d, A tap groove formed between adjacent thread portions 4 (here, a fifth tap groove 9e (chip entry prevention groove) is formed between the first thread portion 4a and the second thread portion 4b, a second tap groove 9b (chip entry prevention groove) is formed between the second thread portion 4b and the third thread portion 4c, a third tap groove 9c (chip entry prevention groove) is formed between the third thread portion 4c and the fourth thread portion 4d, and a fourth tap groove 9d (chip entry prevention groove) is formed between the fourth thread portion 4d and the first thread portion 4a). Coolant supply grooves (here, a first coolant supply groove 63a communicating with the fifth tap groove 9e (chip entry prevention groove) and supplying coolant to the fifth tap groove 9e (chip entry prevention groove), a second coolant supply groove 63b communicating with the second tap groove 9b (chip entry prevention groove) and supplying coolant to the second tap groove 9b (chip entry prevention groove), a third coolant supply groove 63c communicating with the third tap groove 9c (chip entry prevention groove) and supplying coolant to the third tap groove 9c (chip entry prevention groove), and a fourth coolant supply groove 63d communicating with the fourth tap groove 9d (chip entry prevention groove) and supplying coolant to the fourth tap groove 9d (chip entry prevention groove)), provided on the outer periphery of the shank portion 5 and having at least the same number as the number of tap grooves for supplying coolant (which may be supplied in liquid form, mist form, etc.) from the rear end side of the shank portion 5 to each of all the tap grooves. A coolant reservoir 11 in the form of a hole is formed at the rear end of the shank portion 5, and coolant introduction grooves for introducing coolant from the coolant reservoir 11 to each of the coolant supply grooves are provided (here, a first coolant introduction groove 64a for supplying the first coolant supply groove 63a, a second coolant introduction groove 64b for supplying the second coolant supply groove 63b, a third coolant introduction groove 64c for supplying the third coolant supply groove 63c, and a fourth coolant introduction groove 64d for supplying the fourth coolant supply groove 63d). In the right side view, the first coolant supply groove 63a and the first coolant introduction groove 64a are positioned closer to the rake face 14b side of the second thread portion 4b of the fifth tap groove 9e (chip entry prevention groove), In the right side view, the second coolant supply groove 63b and the second coolant introduction groove 64b are positioned closer to the rake face 14c side of the third thread portion 4c of the second tap groove 9b (chip entry prevention groove), In the right side view, the third coolant supply groove 63c and the third coolant introduction groove 64c are positioned closer to the rake face 14c side of the third thread portion 4c of the third tap groove 9c (chip entry prevention groove), In the right side view, the fourth coolant supply groove 63d and the fourth coolant introduction groove 64d are positioned closer to the rake face 14a side of the first thread portion 4a in the fourth tap groove 9 (chip entry prevention groove) (however, excluding the form in which a through coolant supply hole (center through hole) is provided in a through hole form from the rear end side of the shank portion 5 to the tip side of the thread portion 4 for supplying coolant from the rear end side of the shank 5 and discharging it from the tip side of the thread portion 4).

[0043] The form of all the coolant supply grooves including the first coolant supply groove 63a extends in a groove depth form in which a groove is engraved on the groove bottom located in the thread portion 4 through the communicating tap groove, and the groove end point 82 is a position where the coolant flowing through the coolant supply groove is not hindered or its flow direction is changed, so that the coolant scatters (scatters into the hole formed by the tap groove and the counterbore) and more coolant hits the biting portion 2 (reaches the position). The position of the groove end point 82 (= the length of the coolant supply groove) is a position corresponding to 1 / 3 or more of the thread portion range groove part (the part of the tap groove within the range of the thread portion 4) (= the length of the coolant supply groove), preferably a position corresponding to half or more, more preferably a position corresponding to 2 / 3 or more, and most preferably the length of the coolant supply groove that realizes a position where the coolant that has scattered after reaching the groove end point 82 hits the biting portion 2 well (reaches well).

[0044] The cutting tap 65 is an optimal tap for use in through holes or for dedicated use in through holes. Also, a tap groove without a coolant supply groove may be provided (for example, a form in which the fifth tap groove 9e (chip entry prevention groove) is a tapping tap dedicated to a blind hole that functions as a dedicated groove for discharging coolant and chips, with the first tap groove 9a (chip discharge groove) without the first coolant supply groove 63a).

Example

[0045] In Example 12 of the present invention shown in FIG. 12, the main difference from Example 8 is that the back surface of the first thread portion 4a is the back surface 68a, the back surface of the second thread portion 4b is the back surface 68b, the back surface of the third thread portion 4c is the back surface 68c, the back surface of the fourth thread portion 4d is the back surface 68d, and the shank is the shank 69, and a cutting tap 70 is formed.

[0046] In the right side view, the back surface 68a has an inclination angle substantially the same as the side wall angle of the first coolant supply groove 45a, and is in a substantially continuous state with the side wall of the first coolant supply groove 45a with no or a slight step. In the right side view, the back surface 68b has an inclination angle substantially the same as the side wall angle of the second coolant supply groove 45b, and is in a substantially continuous state with the side wall of the second coolant supply groove 45b with no or a slight step. In the right side view, the back surface 68c has an inclination angle substantially the same as the side wall angle of the third coolant supply groove 45c, and is in a substantially continuous state with the side wall of the third coolant supply groove 45c with no or a slight step. In the right side view, the back surface 68d has an inclination angle substantially the same as the side wall angle of the fourth coolant supply groove 45d, and is in a substantially continuous state with the side wall of the fourth coolant supply groove 45d with no or a slight step.

[0047] The shank 69 has a thickness slightly smaller than the hole diameter of the pilot hole A and can be inserted into the pilot hole A (either entirely or partially). The shank may also be configured to have a larger diameter than the diameter of the pilot hole A.

Example

[0048] In Example 13 of the present invention shown in FIG. 13, the main difference from Example 12 is that the back surface of the threaded portion is the back surfaces 73a to 73d, and the first coolant supply groove 40a, the second coolant supply groove 45b, the third coolant supply groove 45c, and the fourth coolant supply groove 45d are connected in a form where the contact surface has substantially no step with substantially the same inclination angle as the inclination angle (including perpendicular) of the back surfaces 73a to 73d, and a cutting tap 74 is formed. The back surfaces 73a to 73d form a substantially vertical wall surface with the cutting groove positioned at the upper part in the right side view. Also, the portions of the second coolant supply groove 45b, the third coolant supply groove 45c, and the fourth coolant supply groove 45d closer to the back surface are in a stepped form and lead to the tap tip. Also, the first coolant supply groove 40a is in the form of a through groove where the groove extends to the tap tip. The groove depths of the second coolant supply groove 45b, the third coolant supply groove 45c, and the fourth coolant supply groove 45d are made deep (for example, the groove bottom position is substantially the same as the groove bottom of the tap groove), and the groove is in the form of a through groove extending to the tap tip, or the groove end point 82 where the groove does not penetrate is loosened. By adopting such a groove form, it is possible to make a large amount of coolant hit the tap tip (the cutting part) forcefully.

[0049] <Cutting tool> The technical idea of the present invention can also be applied to tools having a plurality of grooves such as a roll tap (raised tap), a drill, and a reamer. In particular, it is suitable for a cutting tool that cuttingly expands a pre-formed pilot hole.

Example

[0050] In Example 14 of the present invention shown in FIG. 14, the main difference from Example 9 is that a first coolant supply groove 79a is provided in the first tap groove 9a (chip discharge groove), a second coolant supply groove 79b is provided in the second tap groove 9b (chip entry prevention groove), a third coolant supply groove 79c is provided in the third tap groove 9c (chip entry prevention groove), and a fourth coolant supply groove 79d is provided in the fourth tap groove 9c to form a cutting tap 80. (A) The second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d are formed near the back walls of the back surfaces 15b, 15c, and 15d, and a part or all of them cut into the curved walls of the back surfaces 15b, 15c, and 15d, the groove widths are substantially the same, and the groove bottom positions have a groove depth that is substantially the same as the tap groove and groove bottom positions, and the groove directions are formed in substantially the same direction as the center position line B, Since the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d are formed in such a way that a part or all of them cut into the curved walls of the back surfaces 15b, 15c, and 15d, a coolant supply groove is formed at the tip of the tap where the back wall continues and penetrates forward. Since the coolant supply amount is large and the flow rate is fast, the chips cannot rise in the tap groove and are discharged toward the tip of the tap (such three tap grooves do not function as chip discharge grooves for discharging chips from the opening of the counterbore). Therefore, the coolant supplied to the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d reaches the tip of the tap through the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d, so that the amount of coolant discharged to the tip side increases and the coolant has momentum. (B) The first coolant supply groove 79a is a shallow groove form with a groove depth shallower than that of the second coolant supply groove 79b and a narrow groove form with a narrow groove width, and the formation position is a position close to the rake face 14b. Since the coolant supply amount is smaller than the coolant supply amounts of the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d and the flow path position is shallow, in the thread formation of the stop hole, the combined coolant of the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d, which overrides the coolant flow rate and momentum, does not take the coolant in the first coolant supply groove 79a and entrains all the chips, causing the chips to rise in the first tap groove 9a (chip discharge groove) and be discharged from the counterbore. The first tap groove 9a (chip discharge groove) functions as a discharge groove, and the cooling of the cutting edge 13b etc. of the first tap groove 9a is performed by the combined coolant of the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d. Therefore, the coolant in the first coolant supply groove 79a does not reach the cutting edge and does not function as coolant. And since the first coolant supply groove 79a is provided at a position close to the rake face 14b, there is almost no coolant injection or only a weak influence on the back surface 15a side, which is the opposite side. Thus, the combined coolant of the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d smoothly rises on the back surface 15a side and is discharged. (c) When the counterbore is a through hole, the coolant in the first coolant supply groove 79a reaches the tip of the tap and cools the cutting edge 13b etc., and the coolants in the second coolant supply groove 79b, the third coolant supply groove 79c, and the fourth coolant supply groove 79d also cool their respective cutting edges etc.

[0051] This is the case in the progress of the cutting operation for some time from the start of the thread formation in the counterbore as follows. In the conventional form (for example, the invention of Patent Document 1) in which a coolant supply groove is provided on the axis, for some time from the start of cutting the pilot hole, most of the coolant scatters into the space, resulting in a small supply amount of coolant to the biting portion and a weak momentum. Thus, the biting portion cannot be sufficiently cooled for some time from the start of cutting the pilot hole, and the momentum to extrude the chips to the front of the tap cannot be obtained sufficiently, so the risk of chips remaining in the tap groove increases, and the risks such as chip jamming and clogging of chip masses increase. On the other hand, the cutting tap 80 realizes a form in which coolant with an appropriate amount and momentum reaches the biting portion 2 and hits it surely from the start of thread formation in the pilot hole in the long groove-shaped second coolant supply groove 79b, third coolant supply groove 79c, and fourth coolant supply groove 79d. Therefore, the biting portion can be sufficiently cooled from the start of cutting the pilot hole, and the generated chips can be surely extruded into the pilot hole space in front of the tap.

[0052] The second coolant supply groove 79b, third coolant supply groove 79c, and fourth coolant supply groove 79d may be provided closer to the rake face 14c, rake face 14d, and rake face 14a. Also, the second coolant supply groove 79b, third coolant supply groove 79c, and fourth coolant supply groove 79d may be provided on the curved inclined surfaces (rake faces) of the rake face 14c, rake face 14d, and rake face 14a, and a coolant supply groove with a deeper groove depth can be realized.

Example

[0053] In Example 15 of the present invention shown in FIG. 15, the main difference from Example 14 is that the second coolant supply groove, third coolant supply groove, and fourth coolant supply groove are formed as non-through grooves (here, the groove end 82 is set at a position slightly closer to the shank portion 5 than reaching the biting portion 2) that do not penetrate the tap tip and extend to a position close to the tap tip, namely, the second coolant supply groove 81b, third coolant supply groove 81c, and fourth coolant supply groove 81d of the cutting tap 83. The coolant that has flowed through the second coolant supply groove 81b, the third coolant supply groove 81c, and the fourth coolant supply groove 81d hits or changes its direction along the groove end wall, which is the wall of the groove end point 82, and scatters into the hole formed by the counterbore and the tap groove, achieving the effect of efficiently cooling the cutting edge of the engaging portion 1 and the counterbore wall during cutting. The groove end wall of the groove end point 82 has a gentle curved surface form, an inclined surface form, a steep inclined surface form, a vertical wall, etc. The optimal position of the groove end point 82 changes depending on the form of the groove end wall, but it is preferable that most of the scattered coolant hits (reaches well) the engaging portion 2.

[0054] In Fig. 15, a comparison is made between the second coolant supply groove 10b provided on the central position line B (on the axis center line) (the groove bottom is at the same position as the groove bottom of the second tap groove 9b (chip entry prevention groove)), the second coolant supply groove 81b, the third coolant supply groove 81c, and the fourth coolant supply groove 81d. The coolant in the second coolant supply groove 10b scatters in front of the threaded portion 4, but in the second coolant supply groove 81b, the third coolant supply groove 81c, and the fourth coolant supply groove 81d, the coolant scatters within the hole formed by the tap groove and the counterbore at a position close to the engaging portion 2 of the threaded portion 4, and the scattering occurs at a position where the scattered coolant hits (reaches well) the engaging portion 2 from the start to the end of cutting.

[0055] This means that at the start of threading the counterbore and for some cutting operations thereafter, in the second coolant supply groove 10b, most of the coolant scatters into the space, resulting in less supply and weaker force to the engaging portion 2. In contrast, the cutting tap 83 realizes a form (a form that reaches well) in which an appropriate amount of coolant surely hits the engaging portion 2 with strong force in the second coolant supply groove 81b, the third coolant supply groove 81c, and the fourth coolant supply groove 81d having a long groove form (a form in which the groove end point 82 is located near the engaging portion). As a result, in the case of the threading tap 83, the coolant supply grooves 81b, 81c, and 81d in the form of long grooves are configured such that an appropriate amount and momentum of coolant hits the engaging portion 2 well from the start to the completion of the tapping of the pilot hole, so that the engaging portion can be well cooled from the start of the cutting of the pilot hole, and the chips generated from the start of the cutting can be surely pushed out into the pilot hole space ahead of the tap.

[0056] The second coolant supply groove 81b, the third coolant supply groove 81c, and the fourth coolant supply groove 81d may be provided closer to the rake faces 14c, 14d, and 14a. Also, the second coolant supply groove 81b, the third coolant supply groove 81c, and the fourth coolant supply groove 81d may be provided on the inclined surfaces (rake faces) of the rake faces 14c, 14d, and 14a, and coolant supply grooves with a deeper groove depth can be realized.

Example

[0057] In Example 16 of the present invention shown in FIGS. 16 and 17, the main difference from Example 7 is that In the case of using a blind hole, the third tap groove 9c (chip entry prevention groove) is formed as a seventh tap groove 9g (chip discharge groove) in a form in which chips and coolant are discharged outward from the opening of the pilot hole A, a first coolant supply groove 84a in the form of a shallow groove that supplies a small amount and a thin spray form of coolant to the first tap groove 9a (chip discharge groove) communicating with the first tap groove 9a (chip discharge groove) is provided closer to the back surface 15a of the shank 5, a sixth coolant supply groove 84g in the form of a shallow groove that supplies a small amount and a thin spray form of coolant to the seventh tap groove 9g (chip discharge groove) communicating with the seventh tap groove 9g (chip discharge groove) is provided closer to the back surface 15c of the shank 5, The second tap groove 9b (chip entry prevention groove) and the fourth tap groove 9d (chip entry prevention groove) are configured to function as chip extrusion grooves (chip discharge grooves) through which a larger amount of coolant is supplied than the coolant supply amounts of the first coolant supply groove 84a and the sixth coolant supply groove 84g, and the chips are pushed out (discharged) into the counterbore space ahead of the tap (a chip entry prevention groove that does not function as a chip discharge groove). The second tap groove 9b (chip entry prevention groove) includes a second shallow tap groove portion 9b1 that is a shallow groove extending from the shank 5 side toward the tap tip, and a second deep tap groove portion 9b2 that is located on the tap tip side of the second shallow tap groove portion 9b1 and extends toward the tap tip, and has a groove form deeper than the second shallow tap groove portion 9b1 (the groove bottom is closer to the axis than the groove bottom of the second shallow tap groove portion 9b1). The fourth tap groove 9d (chip entry prevention groove) includes a fourth shallow tap groove portion 9d1 that is a shallow groove extending from the shank 5 side toward the tap tip, and a fourth deep tap groove portion 9d2 that is located on the tap tip side of the fourth shallow tap groove portion 9d1 and extends toward the tap tip, and has a groove form deeper than the fourth shallow tap groove portion 9d1 (the groove bottom is closer to the axis than the groove bottom of the fourth shallow tap groove portion 9d1). A second coolant supply groove 84b is provided that passes through the second shallow tap groove portion 9b1 from the shank 5 and leads to the second deep tap groove portion 9b2. A fourth coolant supply groove 84d is provided that passes through the fourth shallow tap groove portion 9d1 from the shank 5 and leads to the fourth deep tap groove portion 9d2. The second coolant supply groove 84b includes a first groove portion 84b1 passing through the shank portion 5 and a second groove portion 84d2 passing through the second shallow tap groove portion 9b1 (the groove bottoms of the first groove portion 84b1 and the second groove portion 84d2 are in a straight connection form with substantially no step). The fourth coolant supply groove 84d includes a first groove portion 84d1 passing through the shank portion 5 and a fourth groove portion 84d2 passing through the fourth shallow tap groove portion 9d1 (the groove bottoms of the first groove portion 84d1 and the second groove portion 84d2 are in a straight connection form with substantially no step). The coolant passing through the second coolant supply groove 84b is partially discharged and scattered at the end position of the first groove portion 84b1, and the coolant flowing along the groove bottom flows through the second groove portion 84b2 and is discharged into the second deep tapping groove portion 9b2 and scattered to hit the biting portion 2, realizing a form in which efficient cooling and the like are performed. The coolant passing through the fourth coolant supply groove 84d is partially discharged and scattered at the end position of the first groove portion 84d1, and the coolant flowing along the groove bottom flows through the second groove portion 84d2 and is discharged into the fourth deep tapping groove portion 9d2 and scattered to hit the biting portion 2, realizing a form in which efficient cooling and the like are performed. The cutting tap 87 is formed in this form.

[0058] The heights of the second shallow tapping groove portion 9b1 and the fourth shallow tapping groove portion 9d1 only need to be such that the formed female thread does not come into contact, and it is preferably as high as possible. The tips of the second shallow tapping groove portion 9b1 and the fourth shallow tapping groove portion 9d1 should not reach the position of the biting portion 2, and it is preferably set to a length that fits within the range of the complete thread portion 3 (complete thread portion range groove portion). The second shallow tapping groove portion 9b1 and the fourth shallow tapping groove portion 9d1 do not affect the curling of the chips. It is the second deep tapping groove portion 9b2 and the fourth deep tapping groove portion 9d2 that affect the curling of the chips. The coolants in the second coolant supply groove 84b and the fourth coolant supply groove 84d flow into the first tapping groove 9a (chip discharge groove) and the seventh tapping groove 9g (chip discharge groove) depending on their momentum and coolant volume, and do not take into account the coolants in the first coolant supply groove 84a and the sixth coolant supply groove 84g (a coolant supply form in which the coolant volume is small, the momentum is weak, and the coolant is supplied outward in the direction of the tapping groove). While winding in the chips, it rises through the tapping groove to realize discharge from the bottom hole opening to the outside. When it is a tap dedicated to forming a blind hole thread, it is also possible not to provide the first coolant supply groove 84a and the sixth coolant supply groove 84g.

[0059] Since the second shallow tap groove portion 9b1 and the fourth shallow tap groove portion 9d1 thicken the threaded portion 4, a tap with increased torsional strength and reduced breakage is realized. In addition, the groove depths and groove widths of the second coolant supply groove 84b and the fourth coolant supply groove 84d have various forms, and by reducing the groove depth, the torsional strength of the tap is enhanced.

Example

[0060] In Example 17 of the present invention shown in FIG. 18, the main difference from Example 16 is that the groove width of the second tap groove 9b (chip entry prevention groove) is narrowed, the groove width of the fourth tap groove 9d (chip entry prevention groove) is narrowed, the groove width of the first tap groove 9a (chip discharge groove) is widened, the groove width of the seventh tap groove 9g (chip discharge groove) is widened, the arrangement position of the first coolant supply groove 84a is on the central position line B, the arrangement position of the sixth coolant supply groove 84g is on the central position line B, By narrowing the groove width, the curl of the chips formed by the cutting operation of the second tap groove 9b (chip entry prevention groove) and the fourth tap groove 9d (chip entry prevention groove) is reduced, and the chip breakage is accelerated to shorten the chip length. Also, the first tap groove 9a (chip discharge groove) and the seventh tap groove 9g (chip discharge groove) with widened groove widths enable the chips to be discharged quickly, forming a cutting tap 89.

Example

[0061] In Example 18 of the present invention shown in FIG. 19, the main difference from Example 17 is that the form of the second coolant supply groove 84b is such that the groove is also formed at the bottom of the second tap groove 9b (chip entry prevention groove) and has a non-penetrating groove form. The groove end point 82, which is the end point of the groove, is formed at a position that does not reach the sticking portion. The groove end point 82 has a vertical wall form or an inclined wall form and functions to direct the injection direction or scattering direction of the coolant more towards the sticking portion by the sticking portion. The form of the fourth coolant supply groove 84d is such that the groove is also formed at the bottom of the fourth tap groove 9d (chip entry prevention groove) and has a non-penetrating groove form, and the groove end point 82, which is the end point of the groove, is formed at a position that does not reach the sticking part. The groove end point 82 has a vertical wall form or an inclined wall form and functions to direct the injection direction or scattering direction of the coolant more towards the sticking part by the sticking part. The arrangement position of the first coolant supply groove 84a is closer to the scraping surface 14b. The cutting tap 90 is formed such that the arrangement position of the third coolant supply groove 84c is further from the scraping surface 14d.

Example

[0062] In Example 19 of the present invention shown in FIG. 20, the cutting tap 92 In the second tap groove 9b (chip entry prevention groove), a raised portion 94b is formed in a rising form from the groove bottom of the second tap groove 9b (chip entry prevention groove), on the side closer to the scraping surface 14c, communicating with the shank portion 5 and within the range of the complete thread portion 3 (complete thread portion range groove part) towards the tap tip side (axial direction). In the fourth tap groove 9d (chip entry prevention groove), a raised portion 94d is formed in a rising form from the groove bottom of the fourth tap groove 9d (chip entry prevention groove), on the side closer to the scraping surface 14a, communicating with the shank portion 5 and within the range of the complete thread portion 3 (complete thread portion range groove part) towards the tap tip side. A second coolant supply groove 95b with a groove bottom position substantially the same as the groove bottom of the second tap groove 9b (chip entry prevention groove) is provided in a form that passes through the shank 5 and through the raised portion 94b. A fourth coolant supply groove 95d with a groove bottom position substantially the same as the groove bottom position of the fourth tap groove 9d (chip entry prevention groove) is provided in a form that passes through the shank 5 and through the raised portion 94d. On the shank 5, a first coolant supply groove 84a with a groove depth shallower than that of the second coolant supply groove 95b is provided closer to the back surface 15a, and the coolant is injected and supplied into the first tap groove 9a (chip discharge groove). On the shank 5, a sixth coolant supply groove 84g with a groove depth shallower than that of the second coolant supply groove 95b is provided near the back surface 15c in a form of injecting and supplying coolant into the seventh tap groove 9g. The raised portions 94b and 94d do not affect the curling of the chips. What affects the curling of the chips is approximately the range of the engaging portion 2 at the tip of the second tap groove 9b (chip entry prevention groove) and the fourth tap groove 9d (chip entry prevention groove).

[0063] The height of the raised portions 94b and 94d only needs to be such that the formed internal threads do not come into contact, and it is preferably as high as possible. The tips of the raised portions 94b and 94d shall not reach the position of the engaging portion 2 and shall have a length that fits within the range of the complete thread portion 3 (complete thread portion range groove site). The lengths of the raised portions 94b and 94d, the groove end points 82 (= groove lengths) of the second coolant supply groove 95b and the fourth coolant supply groove 95d shall be such that the coolant reaching and scattered from the groove end point 82 can hit the engaging portion 2 well (reach well). The position of the groove end point 82 shall be at a position of 1 / 3 or more, preferably at least half, more preferably 2 / 3 or more of the thread portion range groove site (the tap groove site within the range of the thread portion 4).

[0064] Since the raised portions 94b and 94d thicken the thread portion 4, a tap that is difficult to break with increased torsional strength of the tap is realized.

[0065] It is also possible to adopt a form in which the raised portion 94b and the second coolant supply groove 95b are provided near the back surface 15b, and the raised portion 94d and the fourth coolant supply groove 95d are provided near the back surface 15d.

Example

[0066] In Example 20 of the present invention shown in FIG. 21, the cutting tap 97 is In the second tap groove 9b (chip entry prevention groove), a raised portion 98b is formed in a form that rises from the groove bottom of the second tap groove 9b (chip entry prevention groove) in the form of a raised partition wall, communicates with the shank portion 5, and is within the range of the complete thread portion 3 (complete thread portion range groove portion) toward the tap tip side. In the fourth tap groove 9d (chip entry prevention groove), a raised portion 98d is formed in a form that rises from the groove bottom of the fourth tap groove 9d (chip entry prevention groove) in the form of a raised partition wall, communicates with the shank portion 5, and is within the range of the complete thread portion 3 (complete thread portion range groove portion) toward the tap tip side. A second coolant supply groove 99b having a groove bottom position substantially the same as the groove bottom position of the second tap groove 9b (chip entry prevention groove) is provided in such a manner as to pass through the shank 5 and pass through the raised portion 98b. A fourth coolant supply groove 99d having a groove bottom position substantially the same as the groove bottom position of the fourth tap groove 9d (chip entry prevention groove) is provided in such a manner as to pass through the shank 5 and pass through the raised portion 98d. On the shank 5, a first coolant supply groove 84a having a groove depth shallower than that of the second coolant supply groove 99b is provided near the back surface 15a, and coolant is injected and supplied into the first tap groove 9a (chip discharge groove). On the shank 5, a sixth coolant supply groove 84g having a groove depth shallower than that of the second coolant supply groove 99b is provided near the back surface 15c, and coolant is injected and supplied into the seventh tap groove 9g.

[0067] The raised portions 98b and 98d do not affect the curling of the chips. What affects the curling of the chips is approximately the range of the cutting-in portion 2 ahead of the second tap groove 9b (chip entry prevention groove) and the fourth tap groove 9d (chip entry prevention groove). Since the raised portions 98b and 98d thicken the thread portion 4, a tap with increased torsional strength and less likely to break is realized.

[0068] The height of the raised portions 98b and 98d only needs to be such that the formed female threads do not contact, and it is preferably as high as possible. The tips of the raised portions 98b and 98d should not reach the position of the engaging portion 2 and should be within the range of the complete thread portion 3 (the groove portion of the complete thread portion range), preferably with a length that fits within this range. The length of the raised portion 98b, the length of the raised portion 98d, the groove end point 82 (= groove length) of the second coolant supply groove 99b, and the groove end point 82 (= groove length) of the fourth coolant supply groove 99d should be such that the coolant that reaches the groove end point 82 and scatters is well hit by the engaging portion 2 (a position where it can reach well). The position of the groove end point 82 should be at least 1 / 3 of the thread portion range groove portion (the portion of the tap groove within the range of the thread portion 4), preferably at least half, and more preferably at least 2 / 3. The groove depths and groove widths of the second coolant supply groove 99b and the fourth coolant supply groove 99d can have various forms. If the groove depth is shallower, the torsional strength will be enhanced accordingly. In a form where no coolant supply grooves are provided in the raised portions 98b and 98d, and grooves (hereinafter also referred to as "left groove" and "right groove") are formed on the left and right sides with the raised portions 98b and 98d as partition walls, it is also possible to provide a coolant supply groove in a form where coolant is supplied to the left groove and the right groove or either one of them.

Example

[0069] In Example 21 of the present invention shown in Fig. 22, the main difference from Example 20 is that The groove of the second coolant supply groove 99b is formed (engraved) up to the groove bottom of the second tap groove 9b (chip entry prevention groove), and its groove end point 82 is set at a position passing beyond the raised portion 98b. The groove end point 82 has a vertical wall or inclined wall form. Thus, the coolant hitting the groove end point 82 is in a scattered state where its direction changes and can hit the engaging portion well. The groove of the fourth coolant supply groove 99d is formed (engraved) up to the groove bottom of the fourth tap groove 9d (chip entry prevention groove), and the groove end point 82 is set at a position passing beyond the raised portion 98d. The groove end point 82 is in the form of a vertical wall or an inclined wall. Therefore, the coolant hitting the groove end point 82 is in a scattered state where the direction changes and hits the biting portion well, which is the point where the cutting tap 100 is formed.

Example

[0070] In Example 22 of the present invention shown in FIG. 23, the cutting tap 102 has the following configuration. At a height that does not contact the female thread formed in the pilot hole A, at a length up to the front of the biting portion 2 (a length that does not interfere with the cutting operation of the biting portion and chip formation), or in a form that fits within the range of the complete thread portion (within the complete thread portion groove area) toward the tap tip side in connection with the shank portion, a partition wall 103b is formed at approximately the center of the second tap groove 9b (chip entry prevention groove). The partition wall 103b divides the second tap groove 9b (chip entry prevention groove) into two grooves, and a back surface side groove 104b and a cutting surface side groove 105b are formed. At a height that does not contact the female thread formed in the pilot hole A, at a length up to the front of the biting portion 2 (a length that does not interfere with the cutting operation of the biting portion and chip formation), or in a form that fits within the range of the complete thread portion (complete thread portion groove area) toward the tap tip side in connection with the shank portion, a partition wall 103d is formed at approximately the center of the fourth tap groove 9d (chip entry prevention groove). The partition wall 103d divides the fourth tap groove 9d (chip entry prevention groove) into two grooves, thereby forming a back surface side groove 104d and a cutting surface side groove 105d. A second coolant supply groove 99b having a groove bottom at approximately the same position as the groove bottom of the second tap groove 9b (chip entry prevention groove) is provided in a form that communicates with the cutting surface side groove 105b through the shank 5. The coolant flowing through the second coolant supply groove 99b is jetted into the cutting surface side groove 105b having a narrow groove form and flows through the cutting surface side groove 105b to reach the biting portion 2. A fourth coolant supply groove 99d having a groove bottom at substantially the same position as the groove bottom of the fourth tap groove 9d (chip entry prevention groove) is provided in a form communicating with the cutting surface side groove 105d through the shank 5, and the coolant flowing through the fourth coolant supply groove 99d is jetted into the cutting surface side groove 105d having a narrow groove form, and is configured to flow through the cutting surface side groove 105d and reach the biting portion 2.

[0071] The partition walls 103b and 103d do not affect the curling of the chips. What affects the curling of the chips is substantially the range of the biting portion 2 at the tip of the second tap groove 9b (chip entry prevention groove) and the fourth tap groove 9d (chip entry prevention groove). The tips of the partition walls 103b and 103d are preferably formed in a form that does not reach the position of the biting portion 2 and have a length that is within the range of the complete thread portion 3 (complete thread portion groove portion). Since the coolant is guided to the cutting surface side grooves 105b and 105d having a groove width that is approximately half or less of the groove width of the tap groove, the amount of coolant reaching the biting portion 2 increases. The coolant supply groove may also be provided in the back surface side grooves 104b and 104d.

Example

[0072] In the 23rd embodiment of the present invention shown in Fig. 24, the main difference from the 16th embodiment is that The forms of the second shallow tap groove portion 9b1 and the fourth shallow tap groove portion 9d1 are formed in an inclined surface form that slopes downward substantially straight from the shank side toward the tap tip side. The groove forms of the second coolant supply groove 84b and the fourth coolant supply groove 84d are formed with grooves at the groove bottoms of the second tap groove 9b (chip entry prevention groove) and the fourth tap groove 9d (chip entry prevention groove), and the groove end points are formed as groove end points 82 composed of walls (vertical walls or inclined walls) that change or scatter the direction of the coolant, forming the cutting tap 106. Each groove end point 82 is in a position form that passes through the inclined surface end points 107 of the second shallow tap groove portion 9b1 and the fourth shallow tap groove portion 9d1. The second shallow tapping groove portion 9b1 and the fourth shallow tapping groove portion 9d1 do not affect the curling of the chip. It is the second deep tapping groove portion 9b2 and the fourth deep tapping groove portion 9b2 that affect the curling of the chip.

[0073] Since the second shallow tapping groove portion 9b1 and the fourth shallow tapping groove portion 9d1 thicken the threaded portion 4, a tapping screw with increased torsional strength and difficulty in breaking is realized.

Example

[0074] In the second embodiment 24 of the present invention shown in FIG. 25, the main difference from the first embodiment is that the second coolant supply groove 10b, the third coolant supply groove 10c, and the fourth coolant supply groove 10d are extended to approximately two-thirds of the threaded portion range groove portion, and grooves are formed (grooved) in the tapping grooves, with the groove end points being the groove end points 82. The coolant reaching the groove end points 82 hits the wall of the groove end points 8 or is redirected and scattered to hit the biting portion 2 well, and a cutting tap 109 is formed.

[0075] The groove bottoms of the second tapping groove 9b (chip entry prevention groove), the third tapping groove 9c (chip entry prevention groove), and the second tapping groove 9d are in a substantially planar form, and the groove bottoms of the second coolant supply groove 10b, the third coolant supply groove 10c, and the fourth coolant supply groove 10d are in a substantially planar form. This form increases the groove depth and the groove cross-sectional area to increase the flow rate of the coolant volume. The amount of coolant supplied from the first coolant supply groove 10a to the first tap groove 9a (chip discharge groove) is less than the amount of coolant sprayed from the second coolant supply groove 10b to the fourth coolant supply groove 10d to the tap groove, and is sprayed to a position away from the tap groove. When forming a blind hole, the combined coolant containing the chips from the second coolant supply groove 10b to the fourth coolant supply groove 10d does not push aside the coolant from the first coolant supply groove 10a, or changes its flow direction to a side where the coolant from the chip discharge groove connecting coolant supply groove is less affected, and rises up the first tap groove 9a (chip discharge groove) and is discharged outside from the opening of the pilot hole. Therefore, in blind hole machining, the first tap groove 9a (chip discharge groove) functions as a groove dedicated to discharge. In addition, when machining a through hole, the coolant supplied from the first coolant supply groove 10a to the first tap groove 9a (chip discharge groove) flows through the first tap groove 9a (chip discharge groove) and reaches the chamfer portion 2 to cool the tap tip.

[0076] It is also possible to make the groove shape of the first tap groove 9a (chip discharge groove) the same as that of the second tap groove 9b (chip entry prevention groove) and the groove shape of the first coolant supply groove 10a the same as that of the second coolant supply groove 10b, thereby making it a tap dedicated to blind holes. EXAMPLES

[0077] The 25th embodiment of the present invention shown in FIG. 26 is different from the 16th embodiment in that: The tap grooves are provided in six locations, namely, the first tap groove 9a (chip discharge groove) to the sixth tap groove 9f (chip entry prevention groove), The groove widths of the second tap groove 9b (chip entry prevention groove) to the sixth tap groove 9f (chip entry prevention groove) are narrower than the groove width of the first tap groove 9a (chip discharge groove), The land is provided at six locations, namely, the first screw portion 4a to the sixth screw portion 4f, The land widths of the first thread portion 4a to the sixth thread portion 4f in this embodiment 25 are narrower than the land widths of the first thread portion 4a to the fourth thread portion 4d in the embodiment 16, In the second tap groove 9b (chip entry prevention groove) to the sixth tap groove 9f (chip entry prevention groove) in the present Example 25, second shallow tap groove portions 9b1 to 9f1 are provided. The groove depths of the second shallow tap groove portions 9b1 to 9f1 in the present Example 25 are in a groove depth form shallower than the groove depths of the second shallow tap groove portion 9b1 and the fourth shallow tap groove portion 9d1 in the above Example 16. This is the point where the cutting tap 111 is formed.

[0078] For example, in the cutting tap 87 of Example 16, the number of thread portions is four. In the form where the number of cutting edges of the engaging portion of one thread portion is three, the total number of cutting edges is 3 cutting edges × 4 thread portions = 12 cutting edges. On the other hand, for the cutting tap 111 with six thread portions when the number of cutting edges of the engaging portion is three, the total number of cutting edges is 3 cutting edges × 6 thread portions = 18 cutting edges. That is, since the cutting amount (cutting thickness) of one cutting edge of the cutting tap 111 is less than that of one cutting edge of the cutting tap 87, the durability of the cutting edges of the cutting tap 111 is improved and the chips become thinner, so that the formation of a high-precision internal thread is realized. Also, the chips are curled and cut small in the second deep tap groove portions 9b2 to 9f2 with a narrow groove width where the chips are thin, and are discharged into the under-hole space ahead of the tap, flow into the first tap groove 9a (chip discharge groove), and are discharged outside. In the thread formation of the counterbore, the second tap groove 9b (chip entry prevention groove) to the sixth tap groove 9f (chip entry prevention groove) are tap grooves that function as chip entry prevention grooves that do not discharge chips.

[0079] The height of the second shallow tap groove portions 9b1 to 9f1 only needs to be a height at which the formed internal thread does not come into contact, and it is preferably as high as possible. The coolant for the second shallow tap groove part 9b1 to the sixth shallow tap groove part 9f1 (chip entry prevention groove) flows into the first tap groove 9a (chip discharge groove) depending on its momentum and coolant volume, without considering the coolant in the first coolant supply groove 84a (a coolant supply form with a small coolant volume and weak momentum supplied in the outer direction of the tap groove), and realizes discharge from the bottom hole opening while rising in the tap groove while entraining chips. When forming a blind hole screw tap, it is also possible to adopt a form in which the first coolant supply groove 84a and the third coolant supply groove 84c are not provided. Also, the number of threads is preferably 5 or more, preferably 6 or more.

Embodiment

[0080] In Example 26 of the present invention shown in FIG. 27, the main difference from Example 25 is that the groove depths of the second deep tap groove part 9b2 to the sixth deep tap groove part 9f2 (chip entry prevention groove) are made shallow, and a cutting tap 113 with enhanced torsional strength is formed.

[0081] The taps in the above-described embodiments are cutting taps with cutting edges, but they can also be applied to raising taps that form internal threads by plastic processing without cutting edges. As a concept, in the form of the cutting tap in the embodiment, the form of the raising tap is realized by making the form of each thread crest of the thread part into a thread crest without a cutting edge (rolled thread crest, raised thread crest, rolled thread crest).

[0082] [Supplementary Invention] [Supplementary Invention 1] Partially Chip Discharge Groove Connecting Coolant Supply Groove A tap body having a thread part for forming an internal thread and a shank part, a tap groove formed between adjacent thread parts, and at least the same number of coolant supply grooves as the number of the tap grooves provided on the outer periphery of the shank part for supplying coolant from the rear end side of the shank part to each of all the tap grooves. At least one of the coolant supply grooves is a chip discharge groove communication coolant supply groove having a groove width different from that of the other coolant supply grooves, a groove depth different from that of the other coolant supply grooves, or both a different groove width and a different groove depth. The groove cross-sectional area of the chip discharge groove communication coolant supply groove is smaller than the groove cross-sectional area of the other coolant supply grooves (however, excluding the form in which a through coolant supply hole provided in a through hole form from the rear end side of the shank portion to the tip side of the thread portion is provided for supplying coolant from the rear end side of the shank and discharging it from the tip side of the thread portion), and it is a tap. [Supplementary Invention 2] Partial Chip Discharge Groove Communication Coolant Supply Groove A tap body having a thread portion for forming an internal thread and a shank portion, A tap groove formed between adjacent thread portions, Coolant supply grooves provided on the outer periphery of the shank portion, the number of which is at least the same as the number of the tap grooves, for supplying coolant from the rear end side of the shank portion to each of all the tap grooves. At least one of the coolant supply grooves is a chip discharge groove communication coolant supply groove having a groove depth shallower than the groove depth of the other coolant supply grooves (however, excluding the form in which a through coolant supply hole provided in a through hole form from the rear end side of the shank portion to the tip side of the thread portion is provided for supplying coolant from the rear end side of the shank and discharging it from the tip side of the thread portion), and it is a tap. [Supplementary Invention 3] Partial Small Amount Coolant Supply Groove A tap body having a thread portion for forming an internal thread and a shank portion, A tap groove formed between adjacent thread portions, Coolant supply grooves provided on the outer periphery of the shank portion, the number of which is at least the same as the number of the tap grooves, for supplying coolant from the rear end side of the shank portion to each of all the tap grooves. At least one of the coolant supply grooves is a small coolant supply groove in which the injection supply amount of the coolant is smaller than the injection supply amount of the coolant in the other coolant supply grooves (however, excluding the form in which a through coolant supply hole provided in a through hole form from the rear end side of the shank portion to the tip side of the thread portion is provided for supplying the coolant from the rear end side of the shank and discharging it from the tip side of the thread portion), and it is a tap. [Supplementary Invention 4] Some small coolant supply grooves At the rear end of the shank portion, a coolant introduction groove for introducing coolant into each of the coolant supply grooves is provided. The tap according to Supplementary Invention 3, wherein the groove cross-sectional area of the introduction groove of the small coolant supply groove is smaller than the groove cross-sectional area of the introduction groove of the other coolant supply grooves. [Supplementary Invention 5] Some coolant supply grooves with different arrangements closer to the thread portion A tap body having a thread portion for forming an internal thread and a shank portion. A tap groove formed between adjacent thread portions. A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to each of all the tap grooves, and having at least the same number as the number of the tap grooves. At least one of the coolant supply grooves is a coolant supply groove with a different arrangement whose arrangement position is closer to the thread portion side than the central position line (B) of the tap groove, and the arrangement positions of the other coolant supply grooves are provided on the substantially central position line (B) of the tap groove (however, excluding the form in which a through coolant supply hole provided in a through hole form from the rear end side of the shank to the tip side of the thread portion is provided for supplying the coolant from the rear end side of the shank and discharging it from the tip side of the thread portion), and it is a tap. The "central position line (B) of the tapping groove" means that any form, whether the coolant supply groove reaches the tapping groove, does not reach the tapping groove, or the coolant is jet-supplied to the tapping groove, is included in the technical scope. The same applies to the following supplementary inventions. Also, the "central position line (B) of the tapping groove" is the axis extending from the tip side of the tap to the rear end side of the shank. In the case where the tapping groove is curved, it is a line extending the axis of the shank to the rear end side from the central position of the rear end portion of the tapping groove. This also applies to the following supplementary inventions. [Supplementary Invention 6] Coolant supply groove with different arrangement near partial thread portion The wall surface of each tapping groove is formed by the back surface of the thread portion preceding during thread formation and the rake face of the subsequent thread portion following the preceding thread portion and located on the side opposite to the back surface. The arrangement position of the differently arranged coolant supply groove is a position closer to the back surface side of the preceding thread portion, which is the tap described in Supplementary Invention 5 above. The "preceding thread portion" refers to the thread portion that precedes thread formation (for example, cutting first), and the "subsequent thread portion" refers to the thread portion that follows the preceding thread portion. One tapping groove forms a tapping groove with the back surface of the subsequent thread portion and the rake face of the preceding thread portion as opposing groove wall surfaces. [Supplementary Invention 7] Coolant supply groove with different arrangement near partial thread portion The differently arranged coolant supply groove has a groove cross-sectional area smaller than that of the other coolant supply grooves, a groove depth shallower than that of the other coolant supply grooves, or a coolant jet supply amount smaller than that of the other coolant supply grooves, which is the tap described in any one of Supplementary Inventions 5 and 6 above. [Supplementary Invention 8] Coolant supply groove with different arrangement near (partial / total) thread portion A tap body having a thread portion for forming an internal thread and a shank portion, A tapping groove formed between adjacent thread portions, A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or some of the respective tap grooves. A tap, wherein all or part of the arrangement position of the coolant supply groove is closer to the thread portion side than the center position line (B) of the tap groove (however, except for a form in which a through coolant supply hole provided in a through hole form from the rear end side of the shank portion to the tip side of the thread portion is provided for supplying coolant from the rear end side of the shank and discharging it from the tip side of the thread portion). [Supplementary Invention 9] Coolant supply groove with different arrangements closer to the thread portion (partial or total) A tap body having a thread portion for forming an internal thread and a shank portion. Tap grooves formed between adjacent thread portions. A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or some of the respective tap grooves. The wall surface of each tap groove is formed by the back surface of the preceding thread portion during threading and the rake face of the following thread portion following the preceding thread portion located on the opposite side of the back surface. A tap, wherein all or part of the arrangement position of the coolant supply groove is closer to the back surface side of the preceding thread portion (however, except for a form in which a through coolant supply hole provided in a through hole form from the rear end side of the shank portion to the tip side of the thread portion is provided for supplying coolant from the rear end side of the shank and discharging it from the tip side of the thread portion). [Supplementary Invention 10] A tap body having a thread portion for forming an internal thread and a shank portion. Tap grooves formed between adjacent thread portions. A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or some of the respective tap grooves. A tap, wherein all or part of the arrangement position of the coolant supply groove is closer to the thread portion side than the center position line (B) of the tap groove. [Supplementary Invention 11] A tap body having a thread portion and a shank portion that form an internal thread, A tap groove formed between adjacent thread portions, A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or some of the respective tap grooves, and comprising: The tap groove communicated with the coolant supply groove has a deep tap groove portion located on the tip side of the tap and a shallow tap groove portion having a shallower form than the deep tap groove portion located on the full thread portion side, The shallow tap groove portion is a form in which the coolant supply groove is formed, and is a tap (for example, the tap of Example (16)). [Supplementary Invention 12] A tap body having a thread portion and a shank portion that form an internal thread, A tap groove formed between adjacent thread portions, A coolant supply groove provided on the outer periphery of the shank portion for supplying coolant from the rear end side of the shank portion to all or some of the respective tap grooves, and comprising: At least one of the tap grooves is a narrow-width tap groove having a narrow groove width, The tap grooves other than the narrow-width tap groove have a wide groove width and are wide-width tap grooves, The coolant supply groove communicates with the narrow-width tap groove and is a narrow-width tap groove coolant supply groove in a form for supplying the coolant to the narrow-width tap groove, and is a tap (for example, the tap of Example (17)). [Supplementary Invention 13] A wide-width groove coolant supply groove that is a coolant supply groove communicating with the wide-width tap groove is provided, The form of the wide-width groove coolant supply groove has a groove depth shallower than the groove depth of the narrow-width tap groove coolant supply groove and a groove width narrower than the groove width of the narrow-width tap groove coolant supply groove, The tap according to Supplementary Invention 12 (for example, the tap of Example (18)), having a cross-sectional area smaller than that of the narrow tap groove coolant supply groove, a supply amount of the coolant smaller than the groove width of the narrow tap groove coolant supply groove, or a flow rate slower than the flow rate of the coolant in the narrow tap groove coolant supply groove. [Effect of Supplementary Invention] [Effect of Supplementary Invention 1] Chip discharge groove communication coolant supply groove "At least one of the coolant supply grooves is a chip discharge groove communication coolant supply groove having a groove width different from that of other coolant supply grooves, a groove depth different from that of other coolant supply grooves, or a groove width and a groove depth different from those of other coolant supply grooves, Since the groove cross-sectional area of the chip discharge groove communication coolant supply groove is smaller than the groove cross-sectional area of the other coolant supply grooves, the following operating effects are achieved. (1) In the thread formation of a through hole, coolant is supplied to all the tap grooves. Although the coolant supply amount from the chip discharge groove communication coolant supply groove is smaller than the supply amount from the other coolant supply grooves (because the groove cross-sectional area of the chip discharge groove communication coolant supply groove is smaller than the groove cross-sectional area of the other coolant supply grooves), even in the tap groove receiving the jet supply from such a chip discharge groove communication coolant supply groove, the cutting edge is cooled by the supplied coolant, the frictional resistance is reduced, and the cut chips are pushed downward by the coolant and quickly discharged from the lower opening of the pilot hole. (2) In the thread formation of a blind hole, the supply amount of the coolant from the chip discharge groove communication coolant supply groove to the tap groove (chip discharge groove) is smaller than the supply amount of the coolant from the other coolant supply grooves to the tap groove (chip entry prevention groove). On the other hand, the amount of coolant supplied to the other tap groove (chip entry prevention groove) is larger than the amount of coolant supplied to the tap groove (chip discharge groove). Therefore, in the stop hole, the coolant (including chips) in other coolant supply grooves does not push up the coolant (including chips) in the chip discharge groove communication coolant supply groove or flows to the side with less influence of the coolant, and directly rises through the tap groove (chip discharge groove) to realize the discharge of the coolant and chips from the upper opening of the lower hole (the upper opening of the tap groove hole formed by the tap groove (chip discharge groove) and the lower hole). That is, a tap that can be used without problems even in the use of the stop hole is realized. (3) From (1) and (2) above, a tap that realizes a cooling effect, a friction reduction effect, and a chip discharge effect (hereinafter also referred to as "tap corresponding to both lower holes") is realized both in the use of the through hole and in the use of the stop hole. For example, when the formation of the same-diameter thread in the stop hole and the formation of the same-diameter thread in the through hole are mixed, it can be handled with one type of the same-diameter tap. For example, since the tap can be only one type of the tap corresponding to both lower holes, there is no need to manage the taps for the stop hole and the through hole separately, and mistakes such as using the tap for the through hole in the stop hole can be avoided, simplifying the management of the taps. [Effect of the appended invention 2] Chip discharge groove communication coolant supply groove Since it has a configuration of "at least one of the coolant supply grooves is a chip discharge groove communication coolant supply groove having a groove depth shallower than the groove depth of the other coolant supply grooves", the following effects are achieved. It means that the injection position of the coolant from the chip discharge groove communication coolant supply groove is a position away from the bottom surface of the tap groove to the outside, the injection range is in a thin form, and the injection supply amount of the coolant is smaller than the coolant amount of the other coolant supply grooves. The supply thickness of the coolant is thin and close to the edge of the bottom hole opening (where the female thread is formed during threading). That is, since it is located at a position away from the bottom surface of the tap groove, the coolant supplied by injection is injected to the side close to the wall surface (female thread surface) of the bottom hole of the hole (hereinafter also referred to as "tap groove hole") formed by the tap groove and the bottom hole. Therefore, the coolant is concentrated and injected at a location close to the wall surface of the bottom hole of the tap groove hole, and the coolant injection distribution (hereinafter also referred to as "outer large inner small coolant injection distribution") in which the injection amount decreases as it goes to the bottom surface side of the tap groove is obtained. Due to the outer large inner small coolant injection distribution, it becomes a discharge flow path for the coolant and chips of other coolant supply grooves to flow into, rise, and be discharged outside the bottom hole on the bottom surface side of the tap groove where the suppression of the coolant from the chip discharge groove communication coolant supply groove is weak, and smooth discharge of the coolant and chips is realized, which has the function and effect. That is, in the use of a blind hole, a form is realized in which it is impossible or difficult to suppress the inflow of the coolant and chips of other coolant supply grooves into the tap groove supplied by the chip discharge groove communication coolant supply groove and the discharge to the outside. Therefore, smoother discharge of the chips and coolant is realized. [Effect of Supplementary Invention 3] Small coolant supply groove Since it has a configuration of "at least one of the coolant supply grooves is a small coolant supply groove in which the injection supply amount of the coolant is less than the injection supply amount of the coolant in other coolant supply grooves", it has the same effect as the above-mentioned Supplementary Invention 1. [Effect of Supplementary Invention 4] Small coolant supply groove In the above-mentioned Supplementary Invention 3, "at the rear end of the shank portion, a coolant introduction groove for introducing coolant into each of the coolant supply grooves is provided, Since the groove cross-sectional area of the introduction groove of the small coolant supply groove is smaller than the groove cross-sectional area of the introduction groove of the other coolant supply grooves", it has the following function and effect. For example, in a form where the groove cross-sectional area of the introduction groove of the small amount coolant supply groove is the same as the groove cross-sectional area of the introduction groove of other coolant supply grooves, the amount of coolant in the small amount coolant supply groove is less than that in other coolant supply grooves, so that the injection momentum can be made weak, and this has an operational effect. Therefore, in the use of the stop hole, the force for suppressing the discharge of chips and coolant can be reduced, and thus it is realized that the discharge of chips and coolant from the tap groove receiving the supply of coolant from the small amount coolant supply groove is performed more smoothly. [Effect of Supplementary Invention 5] Different arrangement coolant supply groove "At least one of the coolant supply grooves is a different arrangement coolant supply groove (a position deviated from the central position line (B) of the tap groove toward the threaded portion side) whose arrangement position is closer to the threaded portion side than the central position line (B) of the tap groove, and the arrangement positions of the other coolant supply grooves are provided on the substantially central position line (B) of the tap groove," and thus has the following operational effects. (1) Since the coolant supply groove is provided at a position deviated from the central position line (B) of the tap groove, the position where the coolant flows in is biased. Therefore, with respect to the coolant flow pressure on the side where the coolant supply groove is located, which is one side of the central position line (B), the flow pressure on the side where the coolant supply groove is not located, which is the other side of the central position line (B), becomes smaller. Thus, the other side of the tap groove is in a state where the amount of coolant is less and the flow pressure is smaller (a state that should also be referred to as a flow path) than the one side. In the screw formation of the stop hole, the coolant and chips of the other coolant supply grooves flow in and rise from the other side, which is the flow path where the flow pressure of the coolant in the tap groove where the different arrangement coolant supply groove flows is small and the flow rate is small, and are discharged from the lower hole opening, or flow into the tap groove where the different arrangement coolant supply groove flows, rise, and are discharged outside the lower hole from the other side while resisting the coolant in the different arrangement coolant supply groove, and this has an operational effect. (2) In a tap in which a square portion (a portion gripped on the chuck side so that the tap does not slip and rotate) is provided at the rear end of the shank, and the angular position and the thread portion position of the square portion are the same on the axis (a general form), the central position line (B) of the other coolant supply groove is located at the center of the side that is not the corner of the square portion. Since this side center is a thin portion located inside the outer periphery of the shank, the introduction groove provided at the end of the square portion for introducing coolant from the square portion to the other coolant supply groove becomes shallow, and the groove cross-sectional area of the introduction groove becomes small. Therefore, the amount of coolant introduced is small. However, in the fifth supplementary invention of the present application, since the different-arrangement coolant supply groove is provided at a position closer to the thread portion side than the central position line (B) of the tap groove, the introduction groove provided in the square portion is located closer to the corner side than the side center. Therefore, it has the effect that the introduction groove can be made deeper than the introduction groove on the central position line (B). This means that if it is possible to obtain the supply of the same amount of coolant as the other coolant supply grooves, the introduction groove can be made shallower, which means that the strength of the shank is increased. In a form in which the amount of coolant in the different-arrangement coolant supply groove is less than the coolant supply amount of the other coolant supply grooves, it further has the effect that the different-arrangement coolant supply groove can be made shallower. [Effect of Supplementary Invention 6] Different-arrangement coolant supply groove In the above-mentioned fifth supplementary invention, since the configuration is "the arrangement position of the different-arrangement coolant supply groove is a position closer to the back surface side of the preceding thread portion", it has the same effects as the above-mentioned fifth supplementary invention and the following effects. (1) During the rotation thread forming operation of the tap, in the tap groove portion outside the pilot hole, the air pressure (wind pressure) generated by the rotation directly hits the rake face of the subsequent thread portion and easily flows out of the tap groove. Therefore, the closer the coolant is to the rake face, the more it is pushed out of the tap groove by the wind pressure and flows out. On the other hand, since the back surface of the leading thread portion is a place where the wind pressure does not directly act (is not applied), the coolant injected and supplied from the differently arranged coolant supply groove provided at a position closer to the back surface side of the leading thread portion to the tap groove is not directly hit by the wind pressure generated by the rotation of the tap. Therefore, more coolant is supplied into the pilot hole and reaches the tip of the tap, achieving the following operational effect. (2) According to (1) above, since more coolant can be supplied to the pilot hole, the differently arranged coolant supply groove can be formed in a shallower groove shape than other coolant supply grooves, achieving the following operational effects: the supply amount of coolant can be reduced, or the injection supply flow rate of the coolant can be decreased. (3) According to (2) above, the differently arranged coolant supply groove can be made shallower. The formation of a shallow groove can strengthen and toughen the strength of the shank (the thicker the part of the shank without the groove (solid core part) as the groove is shallower), achieving the following operational effect. [Effect of Supplementary Invention 7] Differently arranged coolant supply groove In any of the above Supplementary Inventions 5 and 6, since the differently arranged coolant supply groove has a groove cross-sectional area smaller than that of the other coolant supply grooves, a groove depth shallower than that of the other coolant supply grooves, or an injection supply amount of coolant smaller than that of the other coolant supply grooves, it achieves the same operational effects as those of any of Supplementary Inventions 5 and 6. [Effect of Supplementary Invention 8] Differently arranged coolant supply groove Since the configuration is such that "the arrangement position of all or part of the coolant supply groove is closer to the thread portion side than the center position line (B) of the tap groove", it achieves the following operational effects as described below. (1) The form in which one arrangement position of the coolant supply groove is closer to the thread portion side than the center position line (B) of the tap groove corresponds to the differently arranged coolant supply groove of Supplementary Invention 5 above, and thus achieves the same operational effects as those of Supplementary Invention 5. In addition, for example, in the form where the two coolant supply grooves are non-uniformly arranged coolant supply grooves, if the coolant supply amount is the same as that of the coolant supply groove on the central position line (B), the groove depth can be made shallower, so that the strength of the shank can be made stronger (the shallower the groove, the thicker the part of the shank without the groove (solid core part)). (2) In the form where all the arrangement positions of the coolant supply grooves are closer to the thread part side than the central position line (B) of the tap groove, since all the coolant supply grooves can be made into shallow grooves, the strength of the shank can be made even stronger (the shallower the groove, the thicker the part of the shank without the groove (solid core part)), and this has the effect described above. [Effect of Supplementary Invention 9] Non-uniformly arranged coolant supply grooves Since it has the configuration of "the arrangement position of all or part of the coolant supply grooves is closer to the back side of the preceding thread part", it has the following effects. (1) In the form where one arrangement position of the coolant supply groove is closer to the back side of the thread part, it has the same effect as the effect of Supplementary Invention 6 described above. Also, in the form where the two arrangement positions of the coolant supply grooves are closer to the back side of the thread part, the strength of the shank can be made stronger (the shallower the groove, the thicker the part of the shank without the groove (solid core part)), and this has the effect described above. (2) In the form where all the arrangement positions of the coolant supply grooves are closer to the back side of the thread part, it has the effect of increasing the amount of coolant reaching the tap tip (biting part). If the amount of coolant reaching the tap tip is not increased (not increased from the same amount as the coolant supply amount of the coolant supply groove provided on the central position line (B) of the tap groove), the coolant supply amount can be reduced, and this can be realized by making the coolant supply groove shallower. Therefore, the formation of a shallow coolant supply groove can make the strength of the shank even stronger (the shallower the groove, the thicker the part of the shank without the groove (solid core part)), and this has the effect described above.

Industrial Applicability

[0083] The present invention is mainly used in industries that manufacture and use cutting tools such as cutting taps, roll taps, and reamers.

Explanation of symbols

[0084] A: Pilot hole, B: Central position line, 1: Cutting tap, 2: Thread engagement part, 3: Full thread part, 4: Thread part, 4a: First thread part, 4b: Second thread part, 4c: Third thread part, 4d: Fourth thread part, 4e: Fifth thread part, 4f: Sixth thread part, 5: Shank part, 6: Square part, 7: Tap body, 9a: First tap groove (chip discharge groove), 9b: Second tap groove (chip entry prevention groove), 9c: Third tap groove (chip entry prevention groove), 9d: Fourth tap groove (chip entry prevention groove), 9e: Fifth tap groove (chip entry prevention groove), 9f: Sixth tap groove (chip entry prevention groove), 9g: Seventh tap groove (chip discharge groove), 10a: First coolant supply groove (chip discharge groove connection coolant supply groove, small amount of coolant supply groove), 10b: Second coolant supply groove, 10c: Third coolant supply groove, 10d: Fourth coolant supply groove, 11: Coolant reservoir, 12a: First coolant introduction groove, 12b: Second coolant introduction groove, 12c: Third coolant introduction groove, 12d: Fourth coolant introduction groove, 13a~13d: Cutting edges, 14a~14d: Rake faces, 15a~15d: Back side, 20: Cutting tap, 21a: First coolant supply groove (chip discharge groove connecting coolant supply groove, small amount of coolant supply groove, differently arranged coolant supply groove), 22a: First coolant introduction groove, 25: Cutting tap, 26: Tap body, 29: First coolant introduction groove 29, 30: Cutting tap, 33a: First coolant supply groove (chip discharge groove connecting coolant supply groove, small amount of coolant supply groove, differently arranged coolant supply groove), 34: Cutting tap, 36a: First coolant supply groove (chip discharge groove connecting coolant supply groove, small amount of coolant supply groove, differently arranged coolant supply groove), 37: Cutting tap, 40a: First coolant supply groove (chip discharge groove connecting coolant supply groove, small amount of coolant supply groove, differently arranged coolant supply groove), 44: Cutting tap, 45b: Second coolant supply groove, 45c: Third coolant supply groove, 45d: Fourth coolant supply groove, 46b: Second coolant introduction groove, 46c: Third coolant introduction groove, 46d: Fourth coolant introduction groove, 50: Cutting tap, 51a: First coolant supply groove, 51b: Second coolant supply groove, 51c: Third coolant supply groove, 51d: Fourth coolant supply groove, 52a: First coolant introduction groove, 52b: Second coolant introduction groove, 52c: Third coolant introduction groove, 52d: Fourth coolant introduction groove, 55: Cutting tap, 63a: First coolant supply groove, 63b: Second coolant supply groove 63c: Third coolant supply groove 63d: Fourth coolant supply groove 64a: First coolant introduction groove 64b: Second coolant introduction groove 64c: Third coolant introduction groove 64d: Fourth coolant introduction groove 65: Cutting tap 68a~68d: Rear surface 69: Shank 70: Cutting tap 73a~73d: Rear surface 74: Cutting tap 79a: First coolant supply groove 79b: Second coolant supply groove 79c: Third coolant supply groove 79d: Fourth coolant supply groove 80: Cutting tap 81a: First coolant supply groove 81b: Second coolant supply groove 81c: Third coolant supply groove 81d: Fourth coolant supply groove 82: Groove end point 83: Cutting tap 84a: First coolant supply groove 84b: Second coolant supply groove 84b1: First groove part 84d2: Second groove part 84c: Third coolant supply groove 84d: Fourth coolant supply groove 84g: Sixth coolant supply groove 84d1: First groove part 84d2: Fourth groove part 9b1: Second shallow tap groove part 9b2: Second deep tap groove part 9c1: Second shallow tap groove part 9c2: Second deep tap groove part 9d1: Fourth shallow tapping groove part, 9d2: Fourth deep tapping groove part, 9e1: Fifth shallow tapping groove part, 9e2: Fifth deep tapping groove part, 9f1: Sixth shallow tapping groove part, 9f2: Sixth deep tapping groove part, 87: Cutting tap, 89: Cutting tap, 90: Cutting tap, 92: Cutting tap, 94b: Raised part, 94d: Raised part, 95b: Second coolant supply groove, 95d: Fourth coolant supply groove, 98b: Raised part, 98d: Raised part, 99b: Second coolant supply groove, 99d: Fourth coolant supply groove, 100: Cutting tap, 102: Cutting tap, 103b: Partition wall, 103d: Partition wall, 104b: Back side groove, 104d: Back side groove, 105b: Cutting surface side groove, 105d: Cutting surface side groove, 106: Cutting tap, 107: Inclined surface end point, 109: Cutting tap, 111: Cutting tap, 113: Cutting tap.

Claims

1. A tap body having a plurality of threaded portions each having a chamfer portion and a complete thread portion, and a shank portion connected to the threaded portions; a tap groove formed between adjacent threaded portions; A coolant supply groove is provided on the outer periphery of the shank portion, and the number of the coolant supply grooves is at least the same as the number of the tap grooves for supplying coolant from the rear end side of the shank portion to each of all of the tap grooves. In the case where the pilot hole for forming the female thread is a blind hole, A part of the tap groove functions as a chip intrusion prevention groove, the chip intrusion prevention groove is configured to function as a groove that releases chips into a pilot hole space, which is a space of the pilot hole expanding forward of the threaded portion, depending on the amount and / or force of the coolant supplied, and does not allow the chips to intrude into the chip intrusion prevention groove; The tap grooves other than the chip entry prevention grooves function as chip discharge grooves that move within the grooves so that the coolant containing the chips discharged from the chip entry prevention grooves into the pilot hole space is discharged to the outside from a pilot hole opening that is an opening of the pilot hole, a chip discharge groove connecting coolant supply groove, which is a coolant supply groove that supplies coolant to the chip discharge groove among the coolant supply grooves, has a coolant supply form that cannot prevent coolant containing chips from entering the chip discharge groove and being discharged to the outside through the pilot hole opening, In the case where the pilot hole is a through hole, The coolant supplied from the chip discharge groove communicating coolant supply groove flows through the chip discharge groove, reaches the tip side of the threaded portion, and cools the tip side (excluding an embodiment in which a through coolant supply hole is provided in the form of a through hole extending from the rear end side of the shank portion to the tip side of the threaded portion, for supplying coolant from the rear end side of the shank portion and discharging it from the tip side of the threaded portion).

2. The tap as described in claim 1, characterized in that the chip discharge groove connecting coolant supply groove has a shallower groove depth and narrower groove width than the coolant supply groove connecting to the chip entry prevention groove, or has a shallower groove depth or narrower groove width.

3. The arrangement position of the coolant supply groove in the tapping groove of the chip discharge groove communication coolant supply groove is a different arrangement form from the arrangement position of the coolant supply groove in the tapping groove that communicates with the chip entry prevention groove, and is a different-arrangement coolant supply groove. The tap according to any one of claims 1 and 2, characterized in that.

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