JP4580894B2 - Manufacturing method of rising tap and rising tap - Google Patents

Description

  The present invention relates to a method for manufacturing a raised tap and a raised tap, and more particularly, to a method for grinding a flank surface of a complete thread and a chamfered thread of the raised tap.

  A shank portion, and a screw portion including a plurality of complete thread threads on the tip side of the shank section and a plurality of biting thread threads that are continuously provided and have a smaller diameter toward the tip. There is known a method of manufacturing a raised tap in which a screw thread and a chamfered screw thread are formed with constant leads. For example, it is described in Patent Document 1.

According to the method of manufacturing the raised tap, (a) a step of polishing the threaded portion in the blank by moving the grinding wheel parallel to the tap axis from the biting portion to the parallel screw portion, and (b) the biting portion in the biting portion. The front flank grinding and the rear flank grinding of the threaded thread are alternately performed by gradually changing the feed amount of the grinding wheel between the front and rear ends of the biting part; and (c) the peak of the biting part. The raised tap is manufactured through a step of polishing so as to be inclined by the same lead. According to this, after the parallel thread is once formed on the entire threaded portion, the biting portion can be ground, so there is no need for the grinding wheel to go in and out at the time of screw grinding of the biting portion. In the case of the build-up tap, it is said that the problem that the tip of the grinding wheel hits the thread side center and the chamfered thread cannot be processed is solved.
Japanese Patent No. 3457248

  By the way, problems still remain in the above-described conventional method for manufacturing a raised tap. That is, once the parallel thread is formed on the entire threaded portion including the biting part and the complete thread, the front flank grinding and the rear flank grinding of the biting thread are performed at the rear end of the leading end of the biting part. Since the grinding wheel is fed alternately by changing the feed amount of the grinding wheel in turn, the screw grinding process is still complicated, which has been a bottleneck in reducing the grinding efficiency and manufacturing cost.

  The present invention has been made in the background of the above circumstances, and an object of the present invention is to provide a method for manufacturing a raised tap in which a screw grinding process is simple and grinding efficiency and manufacturing cost can be reduced.

In order to achieve such an object, the invention according to claim 1 is a threaded portion including a shank portion, a plurality of complete threads, and a plurality of chamfered threads that are continuously provided and have a smaller diameter toward the tip. A short cylindrical annular grinding surface, and a taper shape having an inclination angle equal to the flank angle of the complete thread, adjacent to both sides of the annular grinding surface, and having a smaller diameter as the distance from the annular grinding surface increases the grinding wheels of a pair of inclined ground surface, the a perfect threads and Shokuzuke thread manufacturing method of a continuous thread forming formed tapped constant lead, said plurality of full threads and its At least one of the proximal flank surface and the distal flank surface of a continuous biting screw thread has a constant feed lead for its full thread and a constant feed for its different biting thread. By sending relatively in the axial direction with respect to the threaded portion of the grinding wheel with the over-de, when continuously grinding across the axial direction of the threaded portion, in order to grind the complete thread The grinding wheel is fed by a constant first feed lead, and the grinding wheel is fed by a constant second feed lead that is larger than the first feed lead to grind the proximal flank surface of the biting thread. The ground grindstone is fed by a fixed third feed lead smaller than the first feed lead in order to grind the tip side flank surface of the biting screw thread .

According to the method for manufacturing the raised tap of the invention according to claim 1, at least one of the plurality of complete threads and the proximal end flank surface and the distal end flank face of the chamfered thread continuous therewith, When the grinding wheel is fed relative to the threaded portion in the axial direction using a constant feed lead for the screw and a constant feed lead for the biting screw thread different from that , the flank surface of the complete thread is constant. A constant third feed which is ground by the first feed lead and has a flank surface of the bite thread continuous with the full thread is smaller than the second feed lead or the first feed lead larger than the first feed lead. from being ground at once in succession by the read, that at least one of both sides of the flanks of the full threads and Shokuzuke thread consecutive to it is ground at once , Screw grinding process is simplified, manufacturing cost is less expensive with grinding efficiency is improved.

Here, preferably, in the invention according to claim 2, annular grinding surface of (a) the grinding wheel is one with the same width as the width of the valley of the complete thread, ( b) using the grinding wheel , both the proximal-side flank surface and the distal-side flank surface of the plurality of complete threads, and the proximal-side flank surfaces of the plurality of biting threads continuous with the complete threads; A first grinding step of continuously grinding one of the distal-side flank surfaces over the entire axial direction of the threaded portion; and (c) a proximal-side flank surface and a distal end of the biting screw thread using the grinding wheel A second grinding step of continuously grinding the other of the side flank surfaces. According to this manufacturing method, since at least one of the flank surfaces on both sides of the complete thread and the chamfered thread is ground all at once, the screw grinding process is simplified, the grinding efficiency is improved, and the manufacturing cost is low. It becomes. Further, with respect to the complete thread, since both flank surfaces are ground only by feeding the grinding wheel in one direction, there is an advantage that grinding is performed only by feeding in one direction.

Preferably, as in the invention according to claim 3 , the root diameter of the chamfered thread is the same as the root diameter of the complete thread. In this way, particularly in a small-diameter tap, there is an advantage that a raised tap having a high strength at the tip end portion and less damage can be obtained at a low cost.

Preferably, as in the invention according to claim 4 , the root diameter of the chamfered screw thread is set to be smaller as it is farther from the complete thread. In this way, there is an advantage that a raised tap with a good bite at the tip can be obtained at a low cost.

Preferably, as in the invention according to claim 5 , the lead of the complete thread is a fixed first lead L1, and the lead of the flank surface of the biting thread is a fixed second lead L2. The lead on the front flank surface of the biting screw thread is a fixed third lead L3, the full angle of the biting screw thread is α, and the biting portion of the screw portion where the biting screw thread is provided When the angle is θ, the second lead L2 is defined by the following equation (1), and the third lead L3 is defined by the following equation (2). According to such a manufacturing method, the shank portion includes a plurality of complete screw threads and a screw portion including a plurality of chamfered screw threads that are continuously provided and have a smaller diameter toward the tip. A high-accuracy raised tap in which ridges and chamfered threads are continuously formed with a constant lead can be obtained at low cost.

Preferably, as in the invention according to claim 6 , it is a raised tap formed by any one of the manufacturing methods of the raised tap according to the invention, wherein the lead of the complete thread is a fixed first. A lead L1, a lead on the flank surface of the root end of the bite screw thread is a constant second lead L2, a lead on the tip side flank of the bite screw thread is a constant third lead L3, and the lead screw thread When the full angle is α and the biting angle of the portion of the thread portion where the biting screw thread is provided is θ, the shape of the biting screw thread can be expressed by the following equations (1) and (2). It is to be satisfied. According to this configuration, the shank portion includes a plurality of complete screw threads and a thread portion that is provided continuously therewith and includes a plurality of biting screw threads that have a diameter that decreases toward the tip. A raised tap in which the attached thread is continuously formed with a constant lead can be obtained with high accuracy and at low cost.

  Preferably, in the method of manufacturing the raised tap, (a) in the first grinding step, the complete thread is ground using a fixed first feed lead, and then the biting is performed. The base end side flank surface of the thread is continuously ground using a constant second feed lead larger than the first feed lead, and (b) the second grinding step includes the biting thread Since the tip side flank surface is continuously ground from the tip using a third feed lead that is smaller than the first feed lead, the two flank of the complete screw thread with two types of constant feed leads Surface and flank surface of the chamfered screw thread can be ground at once, and the flank surface of the chamfered screw thread can be ground with a fixed third feed lead, further simplifying the screw grinding process and grinding As the processing efficiency is increased, Theft is inexpensive.

  Preferably, in the method of manufacturing the raised tap, (a) in the first grinding step, the front-side flank surface of the biting screw thread is ground using a constant second feed lead, followed by Grinding with respect to the complete thread using a fixed first feed lead smaller than the second feed lead; (b) the second grinding step includes a proximal flank of the biting thread; Since the surface is ground using a third feed lead that is larger than the first feed lead, the two flank surfaces of the complete thread and the front-side flank surface of the chamfered thread with two types of constant feed leads Can be ground at once, and the flank surface of the chamfered screw thread can be ground with a fixed third feed lead, which further simplifies the screw grinding process, increases the grinding efficiency, and reduces the manufacturing cost. Become.

  Preferably, in the method of manufacturing the raised tap, (a) the grinding wheel includes a thread grinding surface having a cross-sectional shape having the same inclination as the valley shape of the complete thread but having a small axial dimension. (B) a base end side flank surface of the complete screw thread and the chamfer screw thread continuous therewith, a fixed first feed lead with respect to the complete screw thread, and the bit screw thread For the base end side flank surface grinding step, using the second feed lead larger than the first feed lead, respectively, and the chamfered screw thread and the complete thread continuous thereto. Continuously using the leading flank surface with a constant third feed lead smaller than the first feed lead for the biting screw thread and the first feed lead for the full thread The front flank grinding process Including an outer diameter finish grinding step that finishes at least the outer diameter of the chamfered portion, so that the flank surfaces on both sides of the complete thread and the chamfered thread are ground at once for each flank surface. The grinding process is simplified, the grinding efficiency is increased, and the manufacturing cost is reduced.

  Hereinafter, one application example of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an apparatus for carrying out an example of the manufacturing method of the present invention, and shows a conceptual view in plan view of a thread grinding apparatus 12 of a build-up tap 10. The screw grinding device 12 is fixed on the base 14 and the X direction guide device for guiding the cylindrical tap material (blank) 16 in the X direction which is the left and right direction when viewed from the operator. 18 and X direction table 24 guided by X direction guide device 18 in the X direction and controlled by X direction servo motor 20 via feed screw 22 and fixed on base 14, and viewed from the operator. A Y-direction guide device 28 for guiding the grinding wheel 26 in the Y direction, which is the left-right direction, is guided in the Y direction by the Y-direction guide device 28, and is position-controlled by the Y-direction servo motor 30 via the feed screw 32. Y direction table 34 is provided.

  A base end side (shank side) center 37 that is fitted to a base end portion that is one end portion of the tap material 16 so as not to be relatively rotatable and supports the base end portion, and the base end side center 37 rotate about the axis C. A work rotation drive device 40 that is equipped with an electric motor 38 to drive and rotationally drives the tap material 16 with its axis parallel to the X direction, and the tip portion that is the other end of the tap material 16 can be relatively rotated. The center 42 is provided on the X-direction table 24 so as to support the tip portion of the tap material 16 so as to be rotatable around the axis C. In addition, the grinding wheel 26 is provided with a grinding wheel spindle 44 for holding the disc-shaped grinding wheel 26 in a state where its rotational axis is parallel to the X direction, and an electric motor 46 for rotationally driving the grinding wheel spindle 44. A grindstone rotation drive device 48 is provided on the Y-direction table 34.

  An X-direction position sensor 50 for detecting the movement position of the X-direction table 24 is provided in the X-direction guide device 18, and a Y-direction position sensor 52 for detecting the movement position of the Y-direction table 34 is provided in the Y-direction guide device. The detection signals from the X direction position sensor 50 and the Y direction position sensor 52 are supplied to the electronic control unit 54.

  The electronic control unit 54 includes a so-called microcomputer including a CPU, a ROM, a RAM, and an input / output interface. The electronic control unit 54 processes an input signal according to a program stored in the ROM and the RAM in advance, and generates an X direction servo motor 20 and a Y direction servo. By controlling the motor 30, the electric motor 38, and the electric motor 46, the thread grinding surface 26 a that is the outer peripheral grinding surface of the grinding wheel 26 is rotated around the outer periphery of the tap raw material 16 while the tap raw material 16 is rotated around its axis C. By cutting the surface and moving the two relative to each other in the X direction, the tap material 16 is automatically ground in advance and the raised tap 10 is manufactured.

FIG. 2 is a diagram for explaining the configuration of the above-described build-up tap 10. In FIG. 2, a rising tap 10 is held by a machine tool, a shank portion 10a having a square shaft end having a quadrangular cross section surrounded by four surfaces, and a screw positioned on the tip side of the shank portion 10a. Part 10b. Threaded portion 10b has an outer diameter which is a fully threaded portion 58 and having a constant outer diameter D _KH comprises a plurality of full threads 56, a smaller diameter toward the and tip provided continuously to the full thread 56 And a _chamfered portion 62 composed of a plurality of chamfered threads 60 having _DFH . The plurality of full threads 56 and the chamfered threads 60 are formed with a constant lead along one or more helical windings. In FIG. 2, θ is a portion of the screw portion 10 b where the biting thread 60 is formed, that is, the biting angle (the biting gradient angle) of the biting portion 62.

FIG. 3 is a conceptual diagram showing a cross-section of the main part of the raised tap 10, and shows a part of the complete thread 56 and a biting thread 60 that follows the complete thread 56 on the tip side of the screw part 10 b. The complete thread 56 and the counter screw thread 60 are formed so as to be the same first lead L1 between the peaks, and the plurality of complete threads 56 have the same height (same diameter) H _K (= D _KH −D _KL ), but the height H _F (= D _FH −D _FL ) of the biting screw thread 60 gradually decreases linearly (proportionalally) from the height of the complete thread thread 56 toward the tip. In addition, the valley diameter D _FL between the chamfered threads 60 is the same as the valley diameter D _KL between the complete threads 56. In FIG. 3, α indicates the thread angle of the complete thread 56 and the chamfer thread 60, that is, the full angle of the thread.

As shown in FIG. 4, the grinding wheel 26 includes a short cylindrical annular grinding surface 26 a having the same width as the valley of the complete thread 56, and the same inclination angle as the flank angle α / 2 of the complete thread 56. An outer peripheral grinding surface having a chevron-shaped cross section, which is adjacent to the belt-like grinding surface 26a and has a pair of tapered inclined grinding surfaces 26b that are located on both sides of the belt-like grinding surface 26a and have a diameter that decreases with distance from the annular grinding surface 26a. I have. The pair of inclined grinding surfaces 26b are for grinding the flank surfaces, and the annular grinding surface 26a is used to grind the valleys of the complete thread 56 and the chamfered thread 60 to obtain their trough diameters D _KL and together prepare the D _FL, it is intended for adjusting their outer diameter D _KH and D _FH by grinding the summit of complete threads 56 and Shokuzuke thread 60. In the present embodiment, the tip of the outer peripheral grinding surface of the above-mentioned chevron cross section has the same cross-sectional shape as the valley shape of the complete thread 56, that is, the width dimension of the annular grinding surface 26a and the width dimension of the valley of the complete thread 56 are the same. because it has a base end side of the complete thread 56 (shank) flank surface 56 _K and a distal flank face 56 _S is ground simultaneously.

FIG. 5 is a flowchart for explaining the operation of the electronic control unit 54. In step S1 corresponding to the first grinding step or the base end side flank surface grinding step (hereinafter, step is omitted), at least in the finish polishing, the annular grinding surface 26a of the grinding wheel 26 reaches the valley of the biting thread 60. As shown in FIG. 6, the grinding wheel 26 is fed from the tip end portion of the tap blank 16 being driven to rotate about the axis C to the base end portion (shank side end portion). headed to the X direction, a constant of the second lead L2 the engageable portion 62, by being sent a full thread portion 58 in its second lead L2 is smaller than a predetermined first lead L1, the Shokuzuke threads 60 the base end side and the (shank) flank 60 _K the base end side flank 56 of the full threads 56 _K, is at once ground by the grinding stroke in the same feed direction. Further, in this embodiment, the width dimension of the annular grinding surface 26a of the grinding wheel 26 and the width dimension of the valley of the complete thread 56 have the same dimension. simultaneously with grinding of the flanks 56 _K, the tip side flank 56 _S is also ground.

6 shows the shape of the complete thread 56 virtually in order to show the size of the chamfered thread 60 in comparison with the complete thread 56. The diameter D _M of the tap material 16 is shown in FIG. The step of feeding in the Y direction until the annular grinding surface 26a of the grinding wheel 26 reaches the valley of the complete thread 56 may be performed all at once, but usually the grinding load is reduced to reduce the grinding load. In order to reduce this, the biting in the Y direction until reaching the valley of the complete thread 56 is divided into several times, and each time the biting is performed, the grinding wheel 26 is sent in the X direction several times in the same manner as described above. Executed.

Next, in step S2 corresponding to the second grinding process or the tip side flank grinding process, at least in the finish polishing, the annular grinding surface 26a of the grinding stone 26 is fed in the Y direction until it reaches the trough of the biting thread 60. In this state, as shown in FIG. 7, the grinding wheel 26 moves in the X direction from the distal end portion to the proximal end portion of the tap blank 16, and the fixed third lead L <b> 3 smaller than the first lead L <b> 1 at the biting portion 62. In the complete thread portion 58, the leading flank surface 60S of the biting screw thread 60 is ground at once by being fed by the constant first lead L1. Since the complete thread 56 has already been ground in step S <b> 1, it may be sent in the Y direction until the annular grinding surface 26 a of the grinding wheel 26 reaches the valley of the biting thread 60. Thus, complete with the base end side flank 56 _K and a distal flank face 56 _S base end side flank of the Shokuzuke threads 60 60 _K and a distal flank face 60 _S of the thread 56 are ground.

In the grinding in this step S2, when the grinding wheel 26 is sent in the X direction from the tip end portion to the base end portion of the tap blank 16, it may be sent through the biting portion 62 and the complete thread portion 58, or the bite. One or two threads of the complete thread portion 58 may be sent from the attaching portion 62, or only the biting portion 62 may be sent. In FIG. 7, as in FIG. 6, the shape of the complete thread 56 is virtually shown by a one-dot chain line in order to show the size of the biting thread 60 in comparison with the complete thread 56. diameter _{D M} of the tap material 16 is shown. Even in the grinding in this step S2, normally, in order to reduce the grinding removal amount and reduce the grinding load, the biting in the Y direction until reaching the trough of the biting thread 60 is divided into several times. Each time, the grinding wheel 26 is sent in the X direction several times in the same manner as described above.

Here, the base end side flank 60 _K and a distal flank face 60 _S is termed pursued flank surface and stabbing flank surfaces, a second lead L2 at the time of grinding the base end side flank 60 _K is and chasing side lead, the third lead L3 when grinding the distal flank face 60 _S is referred to as advanced side lead. The first lead L1 full thread 56 and the second lead (chase side lead) L2 of the base end side flank face 60 _K of Shokuzuke threads 60, we have a relationship which satisfies (1), the full screw a third lead (lead side lead) L3 of the tip flank surface 60 _S of the first lead L1 and Shokuzuke threads 60 of the mountain 56 are in a relationship satisfying the expression (2). That is, the second lead L2 is determined based on the first lead L1, the bite angle θ, and the full angle α of the thread from the formula (1), and the third lead L3 is determined from the formula (2). , The biting angle θ, and the full angle α of the thread. For example, when the tap is θ = 8 ° 15 ′ for M10 × 1, if the first lead L1 is 0.500 mm, the second lead L2 is 0.542 mm and the third lead L3 is 0. .458 mm.
L2 = L1 + L1 × tan θ × tan (α / 2) (1)
L3 = L1−L1 × tan θ × tan (α / 2) (2)

During grinding the proximal flank 60 _K, the feed amount in the X direction of the grinding wheel 26 at the engageable portion 62 is (L1 + Δ) × (number of ridges + a of Shokuzuke thread 60), the base end side flank surface At the time of grinding at 56 _K , the feed amount in the X direction of the grinding wheel 26 at the complete thread portion 58 is set to (L1 × the number of threads of the complete thread 56). Thus, the total feed amount K12 in the X direction of the grinding wheel 26 when the grinding at once proximal flank face 60 _K and 56 _K is represented by the following formula (3). Further, at the time of grinding the tip side flank 60 _S, feed amount in the X direction of the grinding wheel 26 at the engageable portion 62 is (L1-Δ) × (number of ridges + a of Shokuzuke thread 60), the distal end side during the grinding flank surfaces 56 _S, feed amount in the X direction of the grinding wheel 26 in the fully threaded portion 58 is set to (number of peaks in L1 × complete threads 56). Thus, the total feed amount S12 in X-direction of the grinding wheel 26 when the grinding at once the leading flank surface 60 _S and 56 _S, the following equation (4). In the following equation, “a” is an idle feed amount for giving a margin, and is normally set to 0.5 to 1 which means 0.5 to 1 mountain number.

K12 = (L1 + Δ) × (number of threaded threads 60 + a)
+ (L1 x number of full thread threads 56) (3)
S12 = (L1-Δ) × (number of threads of chamfered thread 60 + a)
+ (L1 x number of complete threads 56) (4)
However, Δ = L1 × tan θ × tan (α / 2)

In step S3 corresponding to the third grinding process or the outer diameter finish grinding process, the grinding wheel 26 is fed relative to the tap material 16 in the Y direction and the X direction as necessary, so that The outer diameter D _FH of the portion 62 and / or the outer diameter D _KH of the complete thread portion 58 is finished using the grinding wheel 26 so as to fall within a predetermined tolerance.

  As described above, according to the method of manufacturing the raised tap of the present embodiment, at least one of the plurality of complete screw threads 56 and the proximal end flank surface and the distal end side flank face of the chamfered screw thread 60 continuous thereto is Using the first feed lead L1 for the complete thread 56 and the second feed lead L2 or the third feed lead L3 for the biting screw thread 60 different from the first feed lead L1, the grinding wheel 26 is axially relative to the screw portion 10b. Therefore, at least one of the flank surfaces on both sides of the complete screw thread 56 and the chamfered screw thread 60 is ground at a time. The grinding process is simplified, the grinding efficiency is increased, and the manufacturing cost is reduced.

Further, according to the method of manufacturing the raised tap of this embodiment, the grinding wheel 26 is fed by the constant first feed lead L1 in order to grind the complete thread 56, and the proximal side flank surface of the biting thread 60 is obtained. As the grinding wheel 26 to grind the 60 _K is fed by the first feed lead L1 and the second feed lead L2 greater than, the grinding in order to grind the tip side flank 60 _S of the engageable threads 60 Since the grindstone 26 is fed by a third feed lead L3 that is smaller than the first feed lead L1, one or the other of the flank surfaces on both sides of the complete thread 56 and the counter screw thread 60 is a constant first feed lead. Since the grinding wheel 26 is sent by L1 and the second lead L2 larger than that or the third lead L3 smaller than that, the grinding is performed at once, so that the thread grinding process is simplified and the grinding process is performed. Manufacturing cost is less expensive with the rate is enhanced.

In addition, according to the method for manufacturing the raised tap of the present embodiment, (a) the grinding wheel 26 has an annular grinding surface 26a whose tip is the same width as that of the valley of the complete thread 56, and its complete thread. And a pair of inclined grinding surfaces 26b located on both sides adjacent to the annular grinding surface 26a and having the same inclination angle as 56 flank angles α / 2, and (b) a plurality of complete screws Both the proximal end flank surface 56 _K and the distal end side flank surface 56 _S of the thread 56, and a plurality of biting screw threads 60 that are continuous with the complete thread 56, the proximal end flank surface 60 _K, and the distal end side flank surface 60 _S one and a first grinding step of continuously grinding across the axial direction of the threaded portion 10a, the other at least the base end side flank 60 of the engageable threads 60 _K and a distal flank face 60 _S, continuous The second grinding process for grinding At least one of the complete thread 56 and the flank surfaces on both sides of the chamfered screw thread 60 is included. Therefore, the screw grinding process is simplified, the grinding efficiency is increased, and the manufacturing cost is reduced. Further, with respect to the complete thread 56, since both flank surfaces are ground only by feeding the grinding wheel 26 in one direction, there is an advantage that grinding is performed only by feeding in one direction.

Further, according to the thread forming manufacturing method of the tap of the present embodiment, since the the root diameter D _FL between Shokuzuke thread 60 is the same as the root diameter D _KL between full threads 56, the thread forming tap 10 Particularly in the case of a small diameter, there is an advantage that the strength of the tip portion is high and damage is reduced.

Further, according to the method for manufacturing the raised tap according to the present embodiment, (a) the first grinding step S1 is performed by grinding the complete thread 56 using the constant first feed lead L1, and subsequently eating it. are those continuously ground by the second feed lead L2 of larger constant than the base end side flank 60 _K Part first feed lead L1 biasing thread 60, (b) a second grinding step S2, , since it is intended to continuously grind the tip using a third feed lead L3 tip side flank 60 _S of constant smaller than the first feed lead L1 of Shokuzuke threads 60, two types of constant can both flanks and Shokuzuke grinding at once base end side flank 60 _K of the threads 60 of full threads 56 in the feed lead, a third feed leading tip side flank 60 _S of Shokuzuke threads 60 of the constant Since it can be ground with L3, it is a screw grinder. Is simplified, manufacturing cost is less expensive with grinding efficiency is improved.

  Next, another application example of the present invention will be described. In the following description, parts common to the embodiments are denoted by the same reference numerals and description thereof is omitted.

In the embodiment shown in FIG. 8, a step of grinding the base end side flank 60 _K of the engageable threads 60 of the engageable portion 62, in a step of grinding the tip side flank 60 _S of Shokuzuke threads 60 The grinding wheel 26 is the same as the above-described embodiment except that the grinding wheel 26 is fed in the Y direction so as to approach or separate from the axis C side of the tap blank 16 at a constant feed pitch t4. That is, the grinding wheel 26 is in the process of grinding the base end side flank 60 _K of Shokuzuke threads 60 are sent to the axis C side of the more taps material 16 toward the tip of the tap material 16 as shown in FIG. 8 in the process of grinding the tip side flank 60 _S of Shokuzuke thread 60 is separated from the axis C side of the tap material 16 increases toward the proximal end of the tap material 16. In FIG. 8, θ ′ is the slope angle of the valley in the biting part 62. Also in this embodiment, the same effect as the above-described embodiment can be obtained, and a raised tap with good biting can be obtained.

In the present embodiment, the flank surface is ground using the second feed lead L2 and the third feed lead L3 that satisfy the expressions (1) and (2), as in the first embodiment, and the proximal end side flank is thus ground. grinding time the total feed amount K12 in the X direction of the grinding wheel 26 at the time of grinding the surface 60 _K and 56 _K at a stroke of grinding the above equations (3), and a distal flank face 60 _S and 56 _S at a stroke The total feed amount S12 in the X direction of the grindstone 26 is expressed by the above-described formula (4). However, Δ in the present embodiment is represented by the following equation.

    Δ = tan (α / 2) × L1 × (tan θ−tan θ ′) / 2

  The peripheral grinding surface of the grinding wheel 66 of FIGS. 9 and 10 includes a pair of inclined grinding surfaces 66 b having the same inclination angle as the flank angle α / 2 of the flank surface of the complete thread 56, and the width of the valley of the complete thread 56. It is comprised from the annular grinding surface 66a of the width dimension smaller than a dimension. FIGS. 9 and 10 are views corresponding to FIGS. 6 and 7 for explaining grinding of the flank surface using the grinding wheel 66. FIG.

In the present embodiment, in step S1 corresponding to the first grinding step or the base end side flank surface grinding step, the annular grinding surface 66a of the grinding wheel 66 reaches the trough of the chamfered thread 60 as in the above-described embodiment. As shown in FIG. 9, the grindstone 66 is fed in the X direction from the distal end portion of the tap blank 16 to the proximal end portion, and in the biting portion 62 from the first lead L1. in the second lead L2 constant large, a complete thread portion 58 at a constant first lead L1, by being sent across the threaded portion 16a, complete with the base end side flank 60 _K of Shokuzuke threads 60 a base end side flank 56 _K of the thread 56 is at once grinding 1 feed stroke in the same direction.

Next, in S2 corresponding to the second grinding step or the tip side flank surface grinding step, the annular grinding surface 66a of the grinding wheel 66 is fed in the Y direction until reaching the trough of the biting screw thread 60, and FIG. As shown in FIG. 5, the grinding wheel 66 is a fixed third lead L3 smaller than the first lead L1 in the biting portion 62 in the X direction from the distal end portion to the proximal end portion of the tap blank 16, and the complete thread portion. by being sent across the threaded portion 10a at a constant first lead L1 at 58, the leading end flank face 56 _S of the tip flank surfaces 60 _S and full threads 56 of Shokuzuke thread 60 is ground at once . Then, in S3 corresponding to the third grinding step or the outer diameter finish grinding step, the outer diameter D _{FH of the} biting portion 62 and / or the outer diameter D _KH of the complete thread portion 58 causes the grinding wheel 66 to be changed as necessary. And is finished to a predetermined tolerance.

In this embodiment, the complete threads 56 and this base end side flank 56 _K and 60 _K of Shokuzuke thread 60 consecutive, a first feed lead L1 constant for its complete threads 56 For the chamfered screw thread 60, the base end side flank surface grinding step S1 for continuously grinding using the second feed lead L2 larger than the first feed lead L1, respectively, the chamfered thread 60 and this the full distal flank face 60 _S and 56 _S of the thread 56, the second feeding lead L2 constant greater than the first feed lead L1 for that engageable threads 60, full thread consecutive to 56 includes a front-end flank surface grinding step S2 in which the first feed lead L1 is continuously ground, so that the flank surfaces on both sides of the complete thread 56 and the chamfered thread 60 are included. Fragment Since each side flank is ground at once, the thread grinding process is simplified, the grinding efficiency is increased, and the manufacturing cost is reduced.

  As mentioned above, although one Example of this invention was described based on drawing, this invention is applied also in another aspect.

  For example, in the above-described screw grinding apparatus 12, the grinding wheels 26 and 66 are sent in the Y direction and the tap material 16 is sent in the X direction. Conversely, the grinding wheels 26 and 66 are sent in the X direction. The tap material 16 may be configured to be sent in the Y direction.

In the grinding step shown in FIG. 5 described above, grinding is performed in the order of S1, S2, and S3. However, the grinding steps need not necessarily be performed sequentially, and the order of the grinding processes can be changed as necessary. It is. For example, according to the method for manufacturing a raised tap when grinding is performed in the order of S2, S1, and S3, first, (a) in S2 corresponding to the first grinding step in this embodiment, the tip of the biting thread 60 that the side flanks 60 _S was cut by using a constant second feed lead L2, followed by grinding with a first feed lead L1 smaller constant than its second feed lead L2 for the complete threads 56 in and, (b) then, in S1 corresponding to a second grinding step of the present embodiment, the third feed lead proximal flank face 60 _K of Shokuzuke threads 60 is greater than Kitai 1 feed leads L1 L3 Therefore, the two flank surfaces of the complete thread 56 and the front-side flank surface of the chamfered screw thread 60 can be ground at once with two types of constant feed leads. Keep the proximal flank surface constant Since the grinding can be performed by the third feed lead L3, the screw grinding process is further simplified, the grinding efficiency is increased, and the manufacturing cost is reduced.

  In the grinding process of the above-described embodiment, the feeding direction of the grinding wheels 26 and 66 in step S1 and the feeding direction of the grinding wheels 26 and 66 in step S2 are set to the same direction in order to further improve the accuracy. Depending on the structure, the direction may be reversed.

  The rising tap 10 may have any number of lobes. Usually, about 3 to 8 lobes are provided.

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

It is a top view which shows notionally the structure of the screw grinding apparatus for performing the grinding method of one application example of this invention. It is a side view explaining the structure of the build-up tap ground by the screw grinding apparatus of FIG. It is principal part sectional drawing which expands and demonstrates the principal part of the raising tap of FIG. It is sectional drawing which expands and shows the thread-grinding surface and outer-diameter grinding surface which were provided in the outer peripheral surface of the grinding wheel with which the screw grinding apparatus of FIG. 1 was equipped. 2 is a flowchart sequentially showing a main part of an automatic grinding operation of the screw grinding apparatus of FIG. FIG. 6 is a diagram for explaining a grinding operation for grinding the proximal-side flank surface in the first grinding step of FIG. 5. FIG. 6 is a diagram for explaining a grinding operation for grinding the front end side flank surface in the second grinding step of FIG. 5. It is a figure equivalent to FIG. 6 explaining the grinding operation | movement in the other application example of this invention. In still another application example of the present invention, a proximal flank surface is formed using a grinding wheel having a thread grinding surface having a cross-sectional shape having the same inclination as the valley shape of a complete mountain but having a small axial dimension. It is a figure explaining the grinding operation for grinding, Comprising: It is a figure equivalent to FIG. FIG. 10 is a diagram for explaining a grinding operation for grinding the front-end flank surface in the second grinding step of the embodiment of FIG. 9, corresponding to FIG. 7.

Explanation of symbols

10: Raising tap 10a: Shank portion 10b: Screw portion 12: Screw grinding device 16: Tap material 26: Grinding wheel 26a: Thread grinding surface 56: Complete thread 56 _S : Complete thread flank _56K : full thread on the proximal end side flank 60: Shokuzuke thread 60 _S: Shokuzuke threads of the distal flank face 60 _K: Shokuzuke threads on the proximal end side flank 66: grinding wheel S1: the base end side flank Surface grinding process S2: Front flank surface grinding process

Claims (6)

A shank portion, and a threaded portion including a plurality of engageable threads whose diameter toward the and tip provided continuously plurality of full threads and therewith an annular grinding face of the short cylindrical, said complete thread A complete grinding screw comprising a grinding wheel having a pair of tapered inclined grinding surfaces having the same inclination angle as the flank angle of the mountain and adjacent to both sides of the annular grinding surface and having a smaller diameter as the distance from the annular grinding surface decreases. A method of manufacturing a raised tap in which a mountain and a chamfered screw thread are continuously formed with a constant lead,
At least one of the proximal flank surface and the distal flank surface of the plurality of complete threads and the continuous chamfered thread is fixed to a constant feed lead for the complete thread and to a different chamfered thread. When grinding continuously over the entire axial direction of the threaded portion by feeding the grinding wheel relative to the threaded portion in the axial direction using the feed lead of
In order to grind the complete thread, the grinding wheel is fed by a constant first feed lead, and in order to grind the proximal-side flank surface of the biting thread, the grinding wheel is more than the first feed lead. The grinding wheel is fed by a constant third feed lead which is smaller than the first feed lead in order to grind the front flank surface of the biting screw thread. A method for manufacturing a raised tap. An annular grinding surface of the grinding wheel has the same width dimension as the width dimension of the complete thread valley,
Using the grinding wheel, both the proximal-side flank surface and the distal-side flank surface of the plurality of complete threads, and the proximal-side flank surface and the distal end side of the plurality of biting threads continuous to the complete thread A first grinding step of continuously grinding one of the flank surfaces over the entire axial direction of the thread portion;
A second grinding step of continuously grinding the other of the proximal flank surface and the distal flank surface of the biting screw thread using the grinding wheel;
The method for producing a thread forming tap according to claim 1, characterized in that it comprises. The process according to claim 1 or 2 in one of the thread forming tap, wherein the root diameter of the diet with threads is the same as the core diameter of the full threads. The process according to claim 1 or 2 in one of the thread forming tap, wherein the root diameter of the diet with threads is made of a small diameter further away from the fully threaded. The lead of the complete thread thread is a constant first lead L1, the lead of the proximal flank face of the biting screw thread is a second lead L2, and the lead of the leading flank face of the biting thread thread is a constant. When the full lead angle of the third lead L3 and the biting screw thread is α, and the biting angle of the portion of the screw portion where the biting screw thread is provided is θ, the second lead L2 is expressed by the following formula ( as defined in 1), the third lead L3 is a manufacturing method of a thread forming tap according to claim 1, characterized in that it is defined by the following equation (2).
L2 = L1 + L1 × tan θ × tan (α / 2) (1)
L3 = L1−L1 × tan θ × tan (α / 2) (2) A raised tap formed by the method of manufacturing a raised tap according to any one of claims 1 to 5 ,
The lead of the complete thread thread is a constant first lead L1, the lead of the proximal flank face of the biting screw thread is a second lead L2, and the lead of the leading flank face of the biting thread thread is a constant. When the full lead angle of the third lead L3 and the biting screw thread is α, and the biting angle of the portion of the screw portion where the biting screw thread is provided is θ, the shape of the biting screw thread is as follows. A rising tap characterized by satisfying the expressions (1) and (2).
L2 = L1 + L1 × tan θ × tan (α / 2) (1)
L3 = L1−L1 × tan θ × tan (α / 2) (2)

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