KR102091818B1 - Method for manufacturing a shaft - Google Patents

Abstract

The present invention relates to a method for processing a shaft using a shaft processing device to process the shape of a shaft by cutting a shaft material while rotating the shaft material around a main axis of a rotation device. The method for processing a shaft includes: a step of pushing a rear end of the shaft material inserted into a collet and enabling a head unit of the shaft material to come into contact with a contact surface of a stopper installed in a housing; a step of gripping the shaft material using the collet and fixing the shaft material; a step of boring a first center hole in a depth shallower than the depth of a center hole with a predetermined size on a rear cross-section of the shaft material using a drilling tool; a step of supporting a live center protruding from the front of a tailstock by inserting the live center into the first center hole and rough-machining the shaft material by a cutting tool by rotating the shaft material using the rotation device; a step of boring a second center hole in the depth same as the depth of the center hole with the predetermined size on the rear cross-section of the shaft material using the drilling tool; and a step of supporting the live center protruding from the front of the tailstock by inserting the live center into the second center hole and performing accurate cutting and whole length processing on the shaft material using the cutting tool.

Description

Shaft processing method {Method for manufacturing a shaft}

The present invention relates to a shaft processing method, and more particularly, to a processing method of a shaft for transmitting power, such as an output shaft of a transmission.

The machining precision of a power transmission shaft such as an output shaft of a transmission is an important factor influencing the operating performance of a mechanical device to which the shaft is applied.

In general, in the case of the output shaft, the outer diameter shake is within 0.05 mm based on both centers, and the overall length difference has a processing requirement that satisfies 0.1 mm or less.

In the case of machining, if the shaking of both centers exceeds 0.05 mm, an eccentricity is generated in the process of touching the hole in the center of the shaft in the axial direction, thereby causing defects.

In order to suppress the defects due to the eccentric machining, when the shaft material is clamped to a chuck made of solidity, concentricity between the chuck and the shaft material must be maintained.

Conventionally, as disclosed in Patent Document 1, clamping is performed using a so-called “power chuck” standard chuck. However, in the case of a power chuck, it is used after a work called self-boring, which requires a skilled worker to do self-boring. In addition, the power chuck must be processed in the same way as the product dimensions, and periodic management should be performed, which is cumbersome to use.

In addition, Patent Document 1 discloses a method of simultaneously processing a cross-section while processing a center hole, in order to solve the reduction in efficiency of machining both ends of a shaft material and forming a center hole and then processing only the outer diameter without cross-section processing. .

However, this method is very limited in application and has a problem of considering the support method of the center. In addition, in this method, there is another problem in that the defect rate increases because it is not precise to process the output shaft applied to the transmission.

Korean Patent Publication No. 10-2017-0119393

The present invention is to solve the above-mentioned problems of the prior art, to provide a shaft processing method capable of maintaining a constant shaking of both centers of the shaft during processing at 0.05 mm or less, and maintaining the entire length constant without changing the length during processing. The purpose.

In order to achieve the above object, according to an aspect of the present invention, as a shaft processing method using a shaft processing device for processing a shape of a shaft by rotating a shaft material around a main axis of a rotating device and cutting. , The shaft processing device is fixed to the rotating device and includes a housing that rotates around the main shaft, and a collet that grips the shaft material, and the shaft processing method pushes a rear end of the shaft material inserted into the collet. Contacting the head portion of the shaft material with the contact surface of the stopper disposed inside the housing, gripping and fixing the shaft material using the collet, and using a drilling tool of a predetermined dimension on the rear end surface of the shaft material. Drilling a first center hole to a depth smaller than the depth of the center hole, and Inserting and supporting a live center protruding in front of a tailstock in a center hole, rotating the shaft material with the rotating device, and roughing the shaft material with a cutting tool; and after the shaft material using a drilling tool Drilling a secondary center hole to the same depth as the center hole of a predetermined dimension in the cross section, and inserting and supporting a live center protruding in front of the tailstock to the secondary center hole, rotating the shaft material with a rotating device, A method of machining a shaft is provided that includes finishing and lengthening the shaft material with a cutting tool.

According to one embodiment, in the shaft processing apparatus, the collet is formed of a plurality of segments separated from each other arranged in a radial shape around the main axis, and an elastic member connecting two adjacent segments, the outer surface of the collet being the A collet inclined surface inclined in the main axis direction, and the collet receiving hole of the housing in which the collet is accommodated includes a housing inclined surface corresponding to the collet inclined surface, and when the collet moves in the direction of the small diameter portion of the collet inclined surface The shaft material, which is uniformly tightened toward the main shaft by the housing inclined surface and is inserted into the center of the collet, is fixed, and the shaft material is gripped and fixed using the collet to fix the collet toward the small diameter portion of the collet inclined surface. It is made by moving the material to fix the shaft.

According to one embodiment, after the step of drilling the center hole may include the step of removing foreign substances inside the center hole by performing air blowing inside the sento hole punched with an air blow device.

1 shows a shaft material that has been processed before machining and a shaft that has been processed, according to an example.
2 is a cross-sectional view of a shaft processing apparatus according to an embodiment of the present invention.
Figure 3 shows a configuration that is fastened to each other inside the housing.
4 is a front view of the stopper support of the shaft processing apparatus of FIG. 2.
5 is a rear view and a side view of the collet fixing hand of the shaft processing apparatus of FIG. 2.
6 is a side cross-sectional view and a rear view of an adjustment stopper of the shaft processing apparatus of FIG. 2.
7 is a side sectional view and a rear view of the collet of the shaft processing apparatus of FIG. 2.
FIG. 8 shows a live center of the shaft processing apparatus of FIG. 2.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Although the present invention has been described with reference to the embodiments shown in the drawings, it is described as one embodiment, whereby the technical spirit of the present invention and its core configuration and operation are not limited.

1 shows a shaft material that has been processed before machining and a shaft that has been processed, according to an example. Shaft material refers to the workpiece to produce the final product, the shaft.

Fig. 1 (a) shows a shaft material 10 'in a raw material composed of a large-diameter head portion 11 and a small-diameter body portion 12 extending from the rear end of the head portion 11. Here, the raw material state is a state formed in a rod shape through a drawing or drawing or forging molding process, and means a state in which a surface cutting or drilling process is not applied.

1 (b) shows the shaft material 10 in which primary turning is completed. The primary turning process forms a cup-shaped inner hole 13 through a drilling process in the head portion 11, secures an outer diameter 15 and a cross section, maintains a squareness, and drills inside the inner hole 13 It is a process of processing the center portion 14, which is the standard of polishing through.

Hereinafter, the term "shaft material" referred to in this specification mainly refers to a shaft material 10 in which primary turning is completed. However, if necessary, the "shaft material" may refer to the shaft material 10 'and / or the shaft material 10.

FIG. 1 (c) shows a shaft 20 having a surface and a cross-section cut by a shaft processing apparatus 1 according to the present embodiment, and FIG. 1 (d) shows additional drilling on the shaft 20 Through the process, a hole 40 penetrating the inside of the shaft is formed to show the final completed shaft 20 '.

The final completed shaft 20 'in this embodiment is used, for example, as the output shaft of the transmission. The shaft 20 'has a function of distributing oil while transmitting power, and a front end spline is formed on the outer side of the head portion 11, and a plurality of holes are formed on the outer diameter portion. An assembly unit for assembling is formed, and a lower spline for power transmission is formed under the assembly. A hole 40 penetrating the inside of the shaft 20 'is provided in the axial direction, and oil is distributed through the hole 40 when the shaft 20' rotates.

In this specification, the term "shaft" may refer to the shaft 20 and / or the shaft 20 ', but mainly refers to the shaft 20 before machining through holes.

That is, the shaft processing apparatus and method according to the present embodiment mainly aims to form the shaft 20 through cutting processing from the shaft material 10 in which primary turning is completed.

Hereinafter, a shaft processing apparatus 1 for performing a shaft processing method according to this embodiment will be described with reference to the drawings.

2 is a cross-sectional view of a shaft processing apparatus 1 according to an embodiment of the present invention.

The shaft processing apparatus 1 according to the present embodiment is a device for processing a shape of a shaft by rotating a shaft material around a main axis of a rotating apparatus and performing cutting, for example, a CNC lathe. .

Referring to FIG. 2, the shaft processing apparatus 1 is provided with a rotating device 4, which provides a rotational force for rotating the shaft material 10 around a main axis O, to the rotating device 4 It includes a chuck device (2) for rotating and clamping the shaft material (10), and a tailstock (3) reciprocable in the front-rear direction to fix the rear end of the shaft material (10).

Furthermore, the shaft processing apparatus 1 includes a cutting tool 400 for cutting the outer diameter and the cross section of the shaft material 10 and a drilling tool 500 for drilling the center hole in the rear end surface of the shaft material 10. do. The cutting tool 400 and the drilling tool 500 may perform a necessary operation by exchanging positions with each other according to a cutting process and a drilling process.

The chuck device 2 includes a housing 100 fixed to the rotating device 4 and rotating, and a collet 200 coupled to the housing 100 to fix the shaft material 10.

The housing 100 includes a first housing 101 fixed to the rotating device 4 and a second housing 102 coupled to the first housing 101.

The inner space formed by the first housing 101 and the second housing 102 includes a draw nut 120, a stopper support 140, a collet fixing hand 130, a fixing stopper 150 and an adjusting stopper 160. Is accepted.

Hereinafter, the configuration will be described in detail with reference to FIGS. 3 to 6.

3 shows a draw nut 120, a stopper support 140, a collet fixing hand 130 and a fixing stopper 150 that are fastened to each other.

The draw nut 120 is screwed around the rear end of the draw tube 101 inserted into the first housing 101. The stopper support 140 is abutted on the rear end surface of the draw nut 120.

4 is a front view of the stopper support 140.

3 and 4, the stopper support 140 includes a cylindrical body portion 142 and a flange portion 141 that protrudes radially from one side of the body portion 142. Although not illustrated in FIG. 4, three screw fastening holes 143 are formed through the flange portion 141 at 2, 6, and 10, respectively, as shown in FIG. 4.

In the center of the stopper support 140, a hand receiving hole 146 having an approximately “Y” shape is formed through the front and rear sides, and a cylindrical stopper receiving groove 147 is formed inside the body 140.

Three collet fixing hands 130 for fixing the collet 200 are inserted into three arm ends of the hand receiving hole 146.

5 shows a rear view and a side view of the collet fixing hand 130.

As shown in (a) of Figure 5, when viewed from the rear, it is formed to be curved in the shape of an arc of the collet fixing hand 130. As shown in (b) of Figure 5, the collet fixing hand 130 of the first surface 132, the second surface 133, the fourth surface 135 and the third surface 134 in order of height It is formed in a stepped shape having four arc surfaces, and the fourth surface 135 is formed higher in height than the third surface 134, so that the hook fastening part 131 is formed at the end of the collet fixing hand 130. To form.

When the second surface 133 of the collet fixing hand 130 is inserted into the hand receiving groove 147, it is formed at the same height as the inner diameter 148 of the hand receiving groove 147. Accordingly, the second surface 133 of the collet fixing hand 130 and the inner diameter 148 of the hand receiving groove 147 surround the entire outer diameter of the fixing stopper 150 inserted into the hand receiving groove 147.

3, the collet fixing hand 130 inserted into the hand receiving hole 146 comes into contact with the draw nut 120, and the draw nut 120 and the collet fixing hand (through the screw 106) 130) are combined with each other.

A fixed stopper 150 having a thickness approximately equal to the depth of the stopper receiving groove 147 is inserted into the stopper receiving groove 147.

A screw fastening groove 151 is formed around the outer circumference of the fixed stopper 150, and a screw fastening hole 152 is formed in the center. When viewed in FIG. 4, the body portion 142 of the stopper support 140 is formed with a screw fastening hole 144 toward the center O at 12, 4 and 8 o'clock respectively. A coupling screw 104 is fastened to each of the screw fastening holes 144, and an end portion of the coupling screw 104 is engaged with the screw fastening groove 151 of the fixed stopper 150 to stop the supporter 140 and the fixed stopper 150 ) Are combined.

Referring to FIG. 2 again, an adjustment stopper 160 is positioned on a rear end surface of the fixed stopper 150.

6 is a side sectional view and a rear view of the adjustment stopper 160.

As shown in Figure 6, the adjustment stopper 160 is provided with a cylindrical body portion 161, the center of the body portion 161 is formed in the screw fastening hole 163. As shown in Figure 2, by fixing the stopper 150 and the adjustment stopper 160 in a state in which the coupling screw 109 is fastened to the screw fastening hole 163 and the screw fastening hole 144 at the same time, the fixed stopper ( 150) and the adjustment stopper 160 are combined.

The rear end surface of the adjustment stopper 160 is a contact surface of the stopper to which the head portion 11 of the shaft material 10 abuts. As shown in FIG. 6, an uneven portion 162 recessed from the rear end surface is formed on the rear end surface of the adjustment stopper 160.

According to the present embodiment, the adjustment stopper 160 is installed so that the uneven portion 162 is always positioned in the lower direction when the rotating device 4 is stopped and the chuck device 2 is in the stopped rotation state.

Referring to FIG. 2 again, a collet receiving hole 107 through which the collet 200 can be inserted is formed in the second housing 102, and the collet receiving hole 107 is moved forward (left in FIG. 2). It has a tapered housing inclined surface 109 with a decreasing diameter.

The collet 200 corresponding to the shape of the collet receiving hole 107 is inserted into the collet receiving hole 107.

7 is a side cross-sectional view and a rear view of the collet 200 according to the present embodiment.

As shown in FIG. 7, the collet 200 according to the present exemplary embodiment is disposed between three sections 201 separated from each other and two adjacent sections 201 arranged in a radial shape around the main axis O It is formed of an elastic member 202 that connects.

As best shown in Figure 7 (a), the front of the collet 200 is inserted into the interior of the housing 100 through the collet receiving hole 107, the hook fastening portion 131 of the collet fixing hand 130 ) Is formed with a hook fastener 220 that can be fastened to. A collet inclined surface 210 inclined in the direction of the main axis O is formed so as to increase the diameter of the cross section around the main axis O toward the bottom of the hook fastener 220.

In the center of the collet 200 is formed in the shaft insertion hole 230 is formed to a size corresponding to the cut outer diameter of the shaft material 10.

The inclination of the collet inclined surface 210 corresponds to that of the housing inclined surface 108 of the collet receiving groove 107.

According to the present embodiment, in order to secure the precision between the collet inclined surface 210 of the collet 200 and the housing inclined surface 108 of the housing 100, the firstly heated housing inclined surface 108 is first polished, and then heat treated After grinding the inclined surface to the collet material, the adhesion between the two inclined surfaces is increased, and then the collet material is completely separated in three cuts to form three sections 201. When the separated pieces are put into a mold and the material of the elastic member 202 (natural rubber in this embodiment) is melted and poured between the sections 201, the sections 201 and the elastic member 202 are welded to each other, so that the elasticity is elastic. The collet 200 is completed.

Referring again to FIG. 2, first, the first housing 101 is securely fixed to the rotating device 4 through the coupling screw 103. The draw nut 120 is coupled to the rear end of the draw tube 110 inserted into the housing 100, and the three collet fixing hands 130 are fixed to the draw nut 120 with a coupling screw 106. . Next, the stopper support 140 is placed in close contact with the first housing 101 by allowing the collet fixing hand 130 to pass through, and after covering the second housing 102, the first with a coupling screw 105 The housing 101, the stopper support 140 and the second housing 102 are fixed at once.

Next, the fixing stopper 150 is inserted into the stopper support 140, and the coupling screw 104 is inserted through the screw fastening hole of the second housing 102 formed at a position corresponding to the screw fastening hole 144. Thus, the second housing 102, the stopper support 140 and the fixed stopper 150 are fixed at a time. Next, the adjustment stopper 160 is inserted into the housing to engage the fixed stopper 150.

The collet 200 is inserted into the collet receiving hole 107, and the hook fastening part 220 of the collet 200 is inserted into the hook fastening part 131 of the collet fixing hand 130 by using a dedicated tool, and the collet 200 ) And the collet fixing hand 130 are combined with each other.

According to such a structure, as shown in FIG. 2, the draw tube 110, the draw nut 120, the collet fixing hand 130 and the collet 200 are connected to each other. At this time, the center of the draw tube 110, the draw nut 120, the collet fixing hand 130, and the collet 200 is concentric with the main axis O which is the rotation center of the rotating device 4.

After inserting the head portion 11 of the shaft material 10 into the shaft insertion hole 230 of the collet 200, the draw tube 110 is moved to the small diameter portion of the collet inclined portion 210 of the collet 200 ( In this embodiment, when moving in the left direction of FIG. 2), the collet fixing hand 130 connected to the draw nut 110 pulls the collet 200 in the direction of the small diameter portion of the collet inclined portion 210.

Accordingly, while the elastic member 202 is uniformly compressed by a kind of wedge action of the housing inclined portion 108 and the collet inclined portion 210, the three sections 201 are tightened and the shaft inserted into the center of the collet 200 The material 10 is tightened.

At this time, due to the action of the housing inclined portion 108 and the collet inclined portion 210, a uniform force acts on the collet 200 in a direction perpendicular to the collet inclined portion 210, and the elastic member 202 is uniform While being compressed, the three sections 201 are evenly tightened toward the main shaft O. Thus, the shaft material 10 supported by the collet 200 is clamped while its axis remains concentric with the main axis O. Conversely, when the collet 200 is pushed in the direction of the large-diameter portion, the clamping is released as the distance between the sections 201 becomes farther due to the elasticity of the elastic member, and the shaft can be removed.

According to the present embodiment, when the collet 200 is operated when compared with the collet of the integral type in which the middle part is cut according to the related art, the precision and concentricity of the shaft 20 are performed because the axis and the main axis O of the shaft material 10 are automatically careful. Can keep.

In this embodiment, the push-pull operation of the collet 200 is performed through the draw tube 110 so as to use a configuration such as a conventional CNC lathe, but is not limited thereto. A separate push device capable of moving the collet 200 back and forth may be provided.

Hereinafter, a shaft processing method using the shaft processing apparatus 1 having the above-described configuration will be described.

It is possible to perform primary turning on the shaft material 10 'in the raw material state using the shaft processing apparatus 1 described above. At this time, the fixed stopper 150 and the adjustment stopper 160 are removed. After inserting the head portion 11 of the shaft material 10 'toward the rear end and the torso 12 to be positioned inside the draw tube 110 through the interior of the housing 100, the shaft material 10' is inserted. It is fixed through the collet 200. The method of fixing the shaft material 10 'through movement of the collet 200 in the main axis direction is the same as above. At this time, the other part of the collet with the same size as above may be fixed to the rest of the head portion 11 whose outer diameter 15 is not cut, and the shaft insertion hole 230 corresponding to the body portion 12 is formed. May be coupled to the device to fix the torso 12. In any case, the head portion 11 is directed toward the rear end of the device (the tailstock 3 direction), and the shaft of the shaft material 10 'is concentric with the main shaft O.

Thereafter, the primary turning is performed using the cutting tool 400 and the drilling tool 500 or another cutting / drilling tool (not shown) to form the shaft material 10.

The shaft material 100 is separated from the device 1, and a fixed stopper 150 and an adjustment stopper 160 are coupled to the interior of the housing 100.

The fixed stopper 150 determines the full-length reference surface of the shaft material 10. The adjustment stopper 160 serves to adjust the length from the full-length reference surface to the rear end surface 16 of the shaft material 10 (ie, the length of the set shaft 20).

With this stopper, the center can be supported and the cross-section can be machined in a state where the working reference plane remains unchanged, so that full-length machining can be accurately performed without additional processing.

The length may be adjusted by separating the adjustment stopper 160 from the stationary stopper 150, and a plurality of adjustment stoppers 160 of various lengths may be prepared to adjust the stopper 160 according to the length of the required shaft 20. You may replace.

After combining the stopper 150 and the adjustment stopper 160 inside the housing 100, the head 11 of the shaft material 10 is inserted into the collet 200, and the tailstock 3 is moved forward. By advancing, the rear end portion 16 of the shaft material 10 is pushed so that the head portion 11 of the shaft material 10 comes into contact with the contact surface which is the rear end surface of the adjustment stopper 160.

Here, for example, a large number of foreign substances may be attached to the contact surface, for example, after finishing the processing of one shaft material 10. As described above, since the uneven portion 162 of the adjustment stopper 160 is always located in the lower direction of the device 1 when stopped, it is possible to provide a space in which a foreign substance buried in a contact surface and then dropped can be accommodated. .

Therefore, when inserted into the device to process another shaft material 10, it can be prevented from being caused by foreign matter on the contact surface of the adjusting stopper 160 in the head portion 11 of the shaft material 10.

Next, by pulling the collet 200 in the direction of the small diameter portion of the collet inclined surface 210 using the draw tube 110 in a state where the shaft material 10 is pushed up to the stopper, the shaft material 10 and the main shaft O Fix concentrically. At this time, the tailstock 3 is retracted back to secure a working space of the drilling tool 500.

Next, the primary center hole is drilled in the rear end face 16 of the shaft material 10 to a depth smaller than the center hole (secondary center hole) 30 of the desired size using the drilling tool 500. According to this embodiment, the primary center hole is drilled to have a depth of 2/3 of the total depth of the predetermined center hole 30.

This is because, for example, the length of the shaft material 10 formed by forging molding is not constant, so that the depth of the center hole is not constant when the center hole is processed at a desired size at one time. If the depth of the center hole is not constant, chip evacuation during processing is not smooth, and the desired concentricity cannot be obtained due to chip interference. As in this embodiment, the primary center hole corresponding to 2/3 of the desired depth is first processed, the cross-section is processed while the center is supported, and then the center hole of the desired depth is processed again to obtain the outer diameter and the overall length of the shaft. If fitted, the shaft 20 with a small error can be stably produced.

Next, the drilling tool 500 is removed and the tailstock 3 is advanced to insert the live center 300 protruding in front of the tailstock 3 into the primary center hole to support the shaft material 10.

According to the present embodiment, the live center 300 has a form for minimizing interference with the cutting tool 400 during cross-section processing.

8 shows a live center 300 according to an embodiment of the present invention.

The drill 501 of the drilling tool 500 according to the present embodiment has a diameter that is approximately constant in diameter on the rear end face 16 of the shaft material 10, and the diameter increases from the front end 31 to the rear end. A center hole 30 having a tapered portion 32 tapered to be formed is formed.

The live center 300 according to the present embodiment has a body portion having a constant diameter from the tip portion 312 and the tip portion 312 having a slope corresponding to the taper portion 32 of the center hole 30 to the rear end ( It has a center pin 310 having a 311).

As shown in FIG. 8, the diameter of the center pin 310 is formed with a dimension smaller than the largest diameter of the center hole 30. According to the present embodiment, the diameter of the body portion 311 of the center pin 310 is approximately 1/2 of the diameter of the center hole 30.

According to this shape, as shown in FIG. 8, the cutting edge 401 of the cutting tool 400 supports the rear end of the shaft material 10 through the center pin 310 while the rear end face of the shaft material 10 It is possible to secure a space to perform cross-section processing by contacting.

After inserting the live center 300 into the primary center hole to support the shaft material 10, the shaft material 10 is rotated using a rotating device 4, and the cutting edge 401 of the cutting tool 400 is rotated. Roughing is performed on the shaft material 10 using.

Subsequently, the tailstock 3 is retracted, and a secondary center hole is drilled in the rear end face 16 of the shaft material 10 to the same depth as the predetermined center hole 30 using the drilling tool 500.

Referring to FIG. 2, the shaft processing apparatus 1 according to the present embodiment includes an air blow apparatus 600 next to the live center 300.

According to this embodiment, after the center hole is drilled, the tailstock 3 is lowered to support the live center 300 to the center hole, and then air blowing is performed inside the center hole using the air blow device 600. To remove foreign substances inside the center hole. Accordingly, it is possible to maintain the cleanliness of the center hole, which is the processing standard, and to improve the precision of the shaft.

After performing air blowing, the live center 300 of the tailstock 3 is inserted into and supported by the secondary center hole 30, the shaft material 10 is rotated by the rotating device 4, and the cutting tool 400 is rotated. ) To finish and lengthen the shaft material 10.

The shaft processing apparatus 1 according to the present embodiment can easily satisfy the standard within the outer diameter shake 0.05 mm based on both centers through the collet 200 that is automatically careful.

In addition, after supporting the center hole by using the live center 300, it is possible to perform both finishing and full-length machining at the same time, thereby inducing a reduction in time for work. Therefore, productivity and work efficiency can be greatly improved.

In addition, the center can be supported and the cross-section can be machined in a state where the working reference plane is not changed by the stopper, so that full-length machining can be performed uniformly and accurately without additional processing.

Claims (3)

As a shaft processing method using a shaft processing device for processing the shape of the shaft by rotating the shaft material around the main axis of the rotating device and performing cutting,
The shaft processing apparatus includes a housing fixed to the rotating apparatus and rotating about the main shaft, and a collet gripping the shaft material,
The shaft processing method,
Pushing the rear end of the shaft material inserted in the collet into contact with a head portion of the shaft material on a contact surface of a stopper disposed inside the housing;
Gripping and fixing the shaft material using the collet;
Drilling a primary center hole to a depth smaller than the depth of the center hole having a predetermined dimension on a rear end surface of the shaft material using a drilling tool;
Inserting and supporting a live center protruding in front of the tailstock to the primary center hole, rotating the shaft material with the rotating device, and roughing the shaft material with a cutting tool;
Drilling a secondary center hole at a depth equal to a center hole having a predetermined dimension on a rear end surface of the shaft material using a drilling tool; And
And inserting and supporting a live center protruding in front of the tailstock to the secondary center hole, rotating the shaft material with a rotating device, and finishing and lengthening the shaft material with a cutting tool. Shaft processing method. According to claim 1,
In the shaft processing apparatus, the collet is formed of a plurality of segments separated from each other arranged in a radial shape around the main axis, and an elastic member connecting two adjacent segments, the outer surface of the collet being inclined in the direction of the main axis A collet receiving hole of the housing including the inclined surface and receiving the collet includes a housing inclined surface corresponding to the collet inclined surface, and when the collet moves in the direction of the small diameter portion of the collet inclined surface, The shaft material, which is evenly tightened toward the main shaft and inserted in the center of the collet, is fixed,
The step of gripping and fixing the shaft material using the collet is performed by moving the collet in the direction of the small diameter portion of the inclined surface of the collet to fix the shaft material. According to claim 1,
Shaft processing method comprising the step of puncturing the secondary center hole to remove foreign substances inside the secondary center hole by performing air blowing inside the secondary center hole that is perforated with an air blow device. .

Images