JPH06320467A - Suction head device for work and the like - Google Patents

Abstract

PURPOSE:To provide a suction head device for a work which is constituted so that contact slide wear is prevented from occurring to a mutual engagement part between a positioning claw to chuck the sucked work and a contact part to operate the positioning claw and the work is accurately positioned and chucked. CONSTITUTION:A suction head device for a work comprises a cylinder body 12 vertically arranged; a suction rod 14 pivotally supported in an airtight manner in the cylinder body 12 and having a lower end in which a suction port 32 is formed; and a positioning claw 48 pivotally mounted in a position in the vicinity of the suction port and a grasping end part 50 and an operating end part 52, which perform operation to chuck a work. A contact part 58 to perform chuck operation of the positioning claw 48 is arranged on the cylinder body 12 side or the suction rod side. The movement range of an operating end part 52 during a time in which the contact part 58 is started to be brought into contact with the operating end part 52 and the work is chucked is set to approximate 45 deg. or less to a horizontal line. Wear is prevented from occurring to a joint between the contact part 58 and the operating end part 52 and accurate positioning and chucking are practicable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suction head device for a workpiece or the like which sucks and conveys a small workpiece such as an IC.

[0002]

2. Description of the Related Art Conventionally, as a structure for adsorbing and transporting a small part such as an IC manufactured in a semiconductor factory or the like to the next process while adsorbing and holding it for assembling electronic parts or the like, for example, an actual development A vacuum chuck device as disclosed in Japanese Patent No. 62-78289 is disclosed. In this device, as shown in FIG. 8, a suction hole is opened inside and a nozzle mounting hole is provided at the lower end in a main body fixed to the tip of an arm protruding upward of a conveyor or the like. The central shaft is provided so as to be able to move up and down in the vertical direction, and a suction nozzle that slides upward by the vacuum pressure supplied to the suction hole of the central shaft is provided in the nozzle mounting hole. In this device, four chuck claws are pivotally mounted so that the claw ends are arranged on the lower peripheral side of the main body. An abutting portion is formed on the upper end of the chuck claw toward the central axis side, and a taper cam is provided on the outer peripheral portion of the central axis on the side facing the abutting portion.

In this vacuum chuck device, when the central shaft descends from the state of FIG. 8, the taper cam also descends accordingly, and at the same time, the suction nozzle in the central shaft pushes open the claw portion at the lower end of the chuck claw. While descending, it contacts the parts. Next, when vacuum pressure is supplied to the suction hole of the central axis and the central axis is raised with the suction nozzle picking up the component, the suction nozzle also rises in the nozzle mounting hole to position the height position of the component, Further, as the central axis rises, the taper cam slides into contact with the contact part of the chuck claw, the upper contact part of the chuck claw is pressed in the direction intersecting the vertical line, and the lower claw part is closed and attracted. Centering is performed by sandwiching the four-sided peripheral side surfaces of the existing component, and in this state, the main body is moved together with the central axis to convey the component adsorbed by the adsorption nozzle to the next step.

[0004]

However, in the above-described vacuum chuck device, the abutment portion on the upper end side of the chuck claw whose central portion is pivotally attached to the main body makes sliding contact with the taper cam of the central shaft on the vertical line. However, since it is pressed outward to open and close the lower end claw, the abutment part on the upper end side of the chuck claw and the taper cam of the central shaft are likely to wear against each other, and this wear causes the parts sucked by the suction nozzle to be chucked. There is a drawback that the nails cannot be accurately positioned. In addition, since the chuck claw has a long leg length from the pivotally attached part to the claw part at the lower end, there is a problem that an error is likely to occur in the positioning operation of the component by the claw part.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to position a positioning claw pivotally mounted in the vicinity of the suction port of the suction rod on the cylinder body side when the suction rod is moved upward. Or, at the contact part provided on the suction rod side,
By engaging the positioning claws at the lower ends of the positioning claws by engaging them in point contact form, there is no sliding wear at the mutual engaging parts of the positioning claws and the abutment parts, and the parts adsorbed to the suction port can be kept accurate for a long time. Another object of the present invention is to provide a suction head device for a workpiece or the like, which is capable of positioning chucks.

[0006]

In order to achieve the above object, the present invention provides a cylinder body 12 provided in the vertical direction.
And a suction rod 14 that is axially supported in the cylinder body 12 in an airtight manner so that it can operate in the longitudinal direction of the cylinder body 12, and that has a suction port 32 for sucking the workpiece M or the like at the lower end thereof.
A gripping end portion 50 that is pivotally attached to a position near the suction port 32 and that operates so as to converge the workpiece M adsorbed by the suction port 32 from the peripheral side to the center side thereof, and operates at the other end portion. A substantially L-shaped positioning pawl 48 having an end portion 52, and an operating end of the positioning pawl 48 on the cylinder body 12 side or the suction rod 14 side as the suction rod 14 moves upward. Gripping end 50 while engaging with 52
An abutting portion 58 for converging the workpiece M to the central side, and the abutting portion 58 and the operating end 52 of the positioning claw 48 start to come into contact with each other, and the gripping end 50 converges the workpiece M or the like to the central side converged position. The working range of the working end is set within an angle range of about 45 degrees with respect to the horizontal line L, and the suction head device 10 for a workpiece or the like is configured.

[0007]

In the suction head device for a workpiece or the like according to the present invention, the workpiece is brought into contact with the suction port at the lower end of the suction rod pivotally supported by the cylinder body to supply vacuum pressure to the suction rod,
After the workpiece is adsorbed to the adsorption port, the adsorption rod rises to a predetermined height in the cylinder body. At this time, the abutting portion provided on the cylinder body side or the suction rod side engages in a point contact manner with the operating end of the positioning pawl pivotally mounted near the suction port, and the lower end side of the gripping end of the positioning pawl is connected. The workpiece is chucked while being contracted, and in this state, the workpiece is moved to the next step to release the workpiece. Since the moving range of the operating end of the positioning pawl that engages with the abutting portion is set within an angle range of approximately 45 degrees with respect to the horizontal line, the operating end of the positioning pawl makes sliding contact with the abutting portion. Without doing so, it simply becomes a point contact state and there is no sliding contact wear, the workpiece can be accurately positioned and chucked for a long time, and it can be conveyed to a predetermined position in the next process.

[0008]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. 1, 2, and 3 show a suction head device 10 for a workpiece or the like according to an embodiment of the present invention. As is clear from the drawing, the suction head device 10 for a workpiece or the like is made of metal, hard synthetic resin, or the like, and is a cylinder body 12 arranged in the up-down direction, and is operated in the longitudinal direction of the cylinder body 12. The cylinder body 12 is provided with a suction rod 14 axially supported in an airtight manner.

The cylinder body 12 has a hole 16 which is formed in the upper and lower surfaces so as to communicate with each other, and a position near the upper end in the hole 16 and
An upper guide 20 and a lower guide 22 having vertical holes 18 for vertically supporting the suction rod 14 in an airtight manner are provided at the lower end portion. The hole 16 may be formed in a cylindrical shape or a rectangular tube shape. The upper guide 20 is fixed by a collar 24 fitted on the inner surface of the upper portion of the hole 16. Further, at the upper end of the hole 16 on the end side of the cylinder body 12, an upper lid 28 having a depressurizing port 26 communicating with the hole 16 is fixed to the upper surface of the cylinder body 12 and is hermetically sealed. A decompression chamber 30 is provided. The lower guide 22 is fixed to the lower surface of the cylinder body 12.

As shown in FIG. 1, the suction rod 14 is
The upper guide 20 and the lower guide 22 are formed of a rod body which is axially fitted and axially supported by the vertical holes 18. The suction port 32 is opened on the lower end surface of the suction rod 14 protruding from the lower guide 22, and the suction pad 33 is fixed.
A decompression chamber joining port 34 is opened at the upper end surface of the adsorption rod 14 fitted into the airtight decompression chamber 30 from the position 2. Furthermore,
The decompression chamber joint port 34 and the suction port 32 are communicated with each other by an intake hole 36 provided at the rod axis of the suction rod 14. As a result, the airtight decompression chamber 30 is communicated with the decompression chamber joining port 34 at the upper end of the adsorption rod 14 and the adsorption port 32 at the lower end via the suction hole 36, and the inside of the airtight decompression chamber 30 is depressurized to a state close to vacuum. Then, this vacuum pressure is applied to the suction port 32.
It is possible to adsorb the processed material.

In the hole 16 defined by the upper guide 20 and the lower guide 22, the attraction rod 14 is provided with a biasing spring 3 for biasing the attraction rod 14 downward.
8 is fitted. The upper and lower ends of the biasing spring 38 are attached to the lower surface of the upper guide 20 and the protrusion 40 provided above the lower guide 22 on the circumferential side surface of the suction rod 14.

As a result, the suction rod 14 is always urged downward, and the suction port 32 can be placed so as to be always close to the workpiece transferred below the suction rod 14. In addition,
The attraction rod 14 is not limited to be biased by the biasing spring 38, but may be biased by using an electromagnet or the like.

Further, a groove 42 communicating with the vertical hole 18 is opened in the lower guide 22, and a detent protrusion 44 protruding from the suction rod 14 is fitted into the groove 42 so that the suction rod 1 can be held.
Rotation around axis 4 is blocked. Airtight decompression chamber 3
When the vacuum pressure in 0 acts on the suction port 32 of the suction rod 14 and sucks the workpiece, the vacuum pressure in the airtight decompression chamber 30 rises, and this vacuum pressure causes the vacuum chamber joining port 34 at the upper end of the suction rod 14 to rise. And the suction rod 14 rises against the elasticity of the biasing spring 38, and the decompression chamber joint port 34 closes.
It is joined to the lower surface of the decompression port 26. At this time the suction rod 1
The work piece adsorbed to the suction port 32 of No. 4 also rises.

As shown in FIGS. 1 and 3, four grooves 46 are formed in a cross shape on the lower surface of the lower guide 22 near the suction port 32 of the suction rod 14, and inside each groove 46. The four positioning claws 48 are arranged so as to face each other. The positioning claw 48 has a gripping end portion 50 that operates so as to converge the workpiece adsorbed on the adsorption port 32 of the adsorption rod 14 from the converging side to the center side thereof, and directs the adsorption rod 14 at the other end portion. It is formed in a substantially L shape with a projecting operating end portion 52. These positioning claws 4
Numeral 8 indicates that the gripping end portion 5 is attached to the pivotal portion 54 provided in the groove 46.
0 and the operating end 52 are pivotally supported at the connected corners, and a biasing spring 56 is provided in the groove 46 and in the operating end 52 so that the gripping end 50 is opened to the suction port 32. It is supported by a bias. By pressing the operating end portion 52 upward, the gripping end portion 50 operates so as to converge the workpiece sucked in the suction port 32 from the convergence side to the center side thereof. The inside angle of the gripping end 50 and the operating end 52 formed in the substantially L shape is not limited to 90 degrees, and the angle range of the inside angle can be freely selected from about 60 degrees to 120 degrees. To form. Further, a block-shaped structure may be used as long as it has a structure in which both ends of the gripping end portion and the operating end portion are arranged in such a positional relationship even if they are not strictly L-shaped.

As shown in FIGS. 1 and 2, the suction rod 1
4 is provided at a position closer to the suction port 32, the abutting portion 58 that causes the gripping end portion 50 to converge toward the center while abutting on the operating end portion 52 of each positioning claw 44 as the suction rod 14 moves upward. ing. The abutting portion 58 has a circular shape, a square shape, or the like that can abut simultaneously with the operating ends 52 of the four positioning claws 48 pivotally mounted to face each other in the four grooves 46 on the lower surface of the lower guide 22. Composed of plate pieces.

A feature of the present invention is that it includes a positioning claw having the operating end and the gripping end, and an abutting part engaging with the positioning claw, and the operating part of the abutting part and the positioning claw. That is, the range of movement of the working end until the gripping end converges the workpiece or the like at the center-side convergence position after the parts start contacting each other is set within an angle range of approximately 45 degrees with respect to the horizontal line. That is, the suction port 32 at the lower end of the suction rod 14
After adsorbing the workpiece M on the
The upper surface of the plate piece of the abutting portion 58 starts to abut on the lower surface of the end of the operating end 52 of the positioning claw 44, and the lower end of the gripping end 50 of each positioning claw 48 positions the workpiece M or the like on the center side convergence position. The range of movement of the operating end portion 52 until it converges on is set to an angle range within about 45 degrees with respect to the horizontal line L connecting the pivotally attaching portions 54 of the facing positioning claws. That is, when the suction rod 14 rises, the plate piece also rises at the same time, but at this time, the upper surface side of the plate piece merely pushes up the operating end 52 of the positioning claw 48 and contacts it in a point contact manner. ,
At the same time, the lower end of the claw is chucked.

At this time, the contacting portions 62 of the positioning claws 48, 48 facing the working ends 52, 52 facing the plate pieces,
At the start of contact, 62 is set within an angle range of about 45 degrees below the horizontal line L connecting the pivot points of the positioning claws 48, 48 of the facing positioning claws 48, 48 shown in FIG. Therefore, the gripping end portion 50 below the pivotal attachment portion 54 of the positioning claw 48 can be formed to be short, and accurate work positioning can be performed. In addition, the contact portion 62 of the operating end portion 52
Is merely pushed up in a state of being mounted and supported on the upper surface of the plate piece of the contact portion 58, so that the chucking of the chuck claw due to the contact sliding wear thereof does not occur, and
The suction head device can be effectively used for a long period of time.

When the suction rod 32 descends and the plate piece 60 separates from the contact portion 62 of the operating end portion 52 of the positioning claw 48, the lower end of each positioning claw 48 opens to open the workpiece M. Become. A packing 64 made of an elastic material such as rubber is attached to the pressure reducing chamber joining port 34 at the upper end of the suction rod 14. As a result, the suction rod 14
The decompression chamber joining port 34 at the upper end of the above absorbs the impact when joining to the lower surface of the decompression port 26 of the lid 28, and the decompression chamber joining port 34
The airtightness between the suction port 32 and the decompression port 26 can be increased, and the suction port 32
The workpieces adsorbed on the can be stably adsorbed and held. When the vacuum pressure acting on the airtight decompression chamber 30 is released and returned to normal pressure, the suction rod 14 is quickly lowered and returned to its original position by the return elasticity of the biasing spring 38, and each positioning claw 48 is moved to the lower end. Rotates outward to release the chuck of the workpiece M.

Next, FIGS. 4, 5 and 6 show another embodiment of the suction head device 10 for a workpiece or the like. As is clear from the figure, the cylinder body 12 and the cylinder body 12
With respect to the construction of the suction rod 14, the upper lid 28, the airtight decompression chamber 30, the biasing spring 38, etc. which are axially supported in the hole 16 of FIG. However, its detailed description is omitted. In this embodiment, as shown in FIG. 4 and FIG. 5, a spacer 66 is fixed to the lower end of the suction rod 14 protruding from the lower guide 22 of the cylinder body 12 at a position close to the suction port 32. Four positioning claws 48 are arranged.

As shown in FIG. 6, the spacer 66 is formed by a disk body having a large wall thickness such as a circle or a quadrangle. In this spacer 66, four grooves 68 are formed so as to communicate with each other in the upper and lower surfaces in an intersecting manner centering on the suction rod 14, and four positioning claws 48 are pivotally mounted in each groove 68. 4 and 5
As shown in FIG. 5, each of the positioning claws 48 has a gripping end 50 that operates so as to converge the workpiece sucked in the suction port 32 from the peripheral side to the center side, and the upper end side of the gripping end 50. A substantially rectangular actuating end portion 5 protruding toward the suction rod 14 side.
2 is formed in a substantially L shape.

In each of the positioning claws 48, the end side of the operating end portion 52 is pivotally supported by a pivotally attached portion 54 provided at a position near the suction rod 14 in the groove 68 of the spacer 66, and the pivotally attached portion is provided. On the lower side of 54, a biasing spring 56 is interposed between the inner surface of the groove 68 and the end surface of the operating end portion 52, and the gripping end portion 50 is formed.
Is biased and supported by the suction port 32 in an open leg shape. Further, the upper end surface of the operating end portion 52 of each positioning claw 48 is
The peripheral edge of the spacer 66 is inclined and projected upward. By pressing the operating end portion 52 protruding from the spacer 66 downward, the gripping end portion 50 operates so as to converge the workpiece M adsorbed to the adsorption port 32 from the converging side to the central side thereof. The inside angle of the gripping end 50 and the operating end 52 formed in the substantially L shape is not limited to 90 degrees, and the angle range of the inside angle can be freely selected from about 60 degrees to 120 degrees. To form.

In this embodiment, as shown in FIGS. 4 and 5, as the suction rod 14 is moved upward, the operating ends 50 of the positioning claws 48 projecting from the upper surface of the spacer 66 are brought into contact with each other. The portion 62 abuts on the lower surface of the lower guide 22 at the lower end of the cylinder body 12, and the operating end 50 abuts in a point contact manner on the lower guide 22 contrary to the ascending suction rod 14, and is pressed downward and gripped. The end portion 52 converges the work piece M. Therefore, the lower guide 22 functions as the contact portion 58.

Also in this embodiment, like the above-mentioned embodiment,
The range of movement of the operating end from the point where the abutting part and the operating end of the positioning claw start to abut until the gripping end converges the workpiece etc. to the center side converging position is within an angle range of approximately 45 degrees with respect to the horizontal line. Is set to. That is, each positioning claw 48
The movement range of the operating end 52 until the abutting portion 62 of the operating end 52 comes into contact with the lower surface of the lower guide 22 of the cylinder body 12 and the lower end of the gripping end 50 converges the workpiece M toward the center side. Is set within an angle range of about 45 degrees with respect to the upper side of the horizontal line L connecting the pivotal attachment portions 54 of the positioning claws 48, 48 facing each other. As a result, the gripping end portion 50 of the positioning claw 48 below the pivotal attachment portion 54 can be formed in a short length, the workpiece can be accurately positioned, and the contact portion 62 is joined to the lower surface of the lower guide 22 in a point contact manner. Therefore, the suction head device can be accurately operated for a long period of time without causing a chucking failure of the chuck claws due to the contact sliding wear.

In the suction head device 10 for a workpiece or the like according to the embodiment of the present invention, the cylinder body 12 may be independently fixed to the tip of an arm of a robot or the like, but as shown in FIG.
It may be installed in parallel above the conveyor C to which the workpiece M is transferred. In the case of parallel installation, for example, a guide 72 having a cross section is fixed to the front surface of the holder 70 arranged in the left-right direction, and the guides 72 are formed on the rear surface of each cylinder body 12 as shown in FIGS. The provided dovetail groove 74 is fitted into the guide 72 via the packing 76, and a bolt 78 is screwed into a bolt hole opened from the upper surface of the cylinder body 12 to the dovetail groove 74 to attach each cylinder body 12 to the holder 70. Fix in parallel.

Further, the holes at both ends of the holder 70 are fitted into the shafts 82, 82 protruding from the front surfaces of the sliders 80, 80 guided by the guides 79, 79 toward the conveyor C, and the clamps 84, 84 are attached. The holder 70 is attached to and detached from the sliders 80, 80 by being attached to the shafts 82, 82. Then, the lower end suction port 32 of the suction rod 14 of each cylinder body 12 is set with a slight gap from the upper surface of the workpiece M conveyed by the conveyor C. Further, the pressure reducing port 26 of each cylinder body 12
The air hose 86 connected to the above may be connected to a vacuum pump (not shown) or the like via a control valve.

As described above, in the suction head device 10 for a workpiece or the like according to the embodiment of the present invention, the cylinder body 1
By connecting an air hose 86 to the decompression port 26 of the upper lid 28 of the upper surface of 2 to supply vacuum pressure to the airtight decompression chamber 30, the workpiece M conveyed by the conveyor C or the like at the adsorption port 32 at the lower end of the adsorption rod 14. Adsorb. After that, when the suction rod 14 rises to lift the workpiece M, the abutting portion 58 fixed to the lower end portion of the suction rod 14 causes the lower guide 22 to move.
The positioning claws 4 are abutted against the operating ends 52 of the four positioning claws 48 pivotally mounted on the lower surface of the
The side surfaces and the front and rear surfaces of the workpiece M are accurately positioned on the inner surface of the lower end of the gripping end portion 50 of FIG. Further, the positioning claws 48 are pivotally mounted near the suction port 32 at the lower end of the suction rod 14 via the spacer 66, and the operating end 52 of the positioning claw 48 is projected on the upper surface of the spacer 66, whereby the suction is performed. When the rod 14 is lifted to lift the workpiece M, each positioning claw 48
Of the workpiece M on the lower end of the holding end 50 of each positioning claw 48 while the operating end 52 contacts the lower surface of the lower guide 22 of the cylinder body 12 and is pushed downward. Also, the front and rear surfaces can be accurately positioned.

After that, the workpiece M sucked and chucked at the lower end of the suction rod together with each cylinder 12 is moved to the next step, and the supply of the vacuum pressure to the suction rod 14 is stopped at a predetermined position. Thereby, the cylinder body 12
The suction rod 14 descends inside to open the positioning claws 44 to release the suctioned workpiece M. Therefore,
In the suction and positioning operation of the workpiece, the operating end 52 of each positioning claw 48 comes into point contact with the contact portion 58 provided on the cylinder body side or the suction rod side, so that the contact portion 62 comes into contact therewith. Each positioning claw 4 pivotally attached to the lower surface of the cylinder body does not cause wear due to sliding contact.
The leg length of 8 can also be formed short, and accurate positioning operation without error can be performed. Further, the workpiece can be positioned easily and promptly in conjunction with the operation of sucking and lifting the workpiece M by the suction rod 14 using the vacuum pressure.

[0028]

As described above, according to the suction head device for a workpiece or the like according to claim 1, the cylinder body provided in the vertical direction and the cylinder body provided so as to operate in the longitudinal direction of the cylinder body are the same. A suction rod that is supported in an airtight manner in the cylinder body and has a suction port for sucking a workpiece, etc. at the lower end, and a workpiece that is pivotally mounted in the vicinity of the suction port and that is sucked in the suction port. It has a gripping end portion that operates so as to converge from the edge side to the center side thereof, and has a substantially L-shaped positioning claw having an operating end portion at the other end portion, and on the cylinder body side or the suction rod side. A contact portion is provided which converges the gripping end portion to the center side while engaging with the operating end portion of the positioning pawl as the suction rod moves upward, and the contact portion and the operating end portion of the positioning pawl are provided. When they start contacting, the gripping end converges the workpiece etc. on the center side. By setting the moving range of the operating end until it converges on the horizontal position within an angle range of about 45 degrees with respect to the horizontal line, the engaging part between the operating end of the positioning claw and the abutting part is pointed. This makes it possible to convey and move the workpieces that have been adsorbed over a long period of time while accurately positioning the workpieces without causing sliding contact and making contact.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a suction head device for a workpiece or the like according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view of a state in which a workpiece is adsorbed and lifted.

FIG. 3 is a view taken along the line AA of FIG.

FIG. 4 is a vertical sectional view of a suction head device for a workpiece or the like according to another embodiment of the present invention.

5 is a vertical cross-sectional view of a state in which a workpiece is sucked up and lifted by the suction head device of FIG.

6 is a partially enlarged arrow view taken along the line BB of FIG.

FIG. 7 is a perspective view of a suction head device in which cylinder bodies are installed in parallel.

FIG. 8 is an explanatory sectional view showing a conventional vacuum chuck device.

[Explanation of symbols]

 10 Suction head device for workpieces 12 Cylinder body 14 Suction rod 32 Suction port 48 Positioning claw 50 Gripping end 52 Operating end 54 Pivoting part 58 Abutting part M Workpiece L horizontal line

Claims (1)

[Claims] 1. A vertically arranged cylinder body, and an airtight shaft supported in the cylinder body so as to operate in the longitudinal direction of the cylinder body, and a suction port for sucking a workpiece or the like at a lower end portion. A suction rod provided, and a gripping end that is pivotally attached to a position in the vicinity of the suction port and that operates so as to converge the workpiece sucked in the suction port from the peripheral side to the center side thereof, and the other end. A substantially L-shaped positioning claw having an operating end portion on the cylinder body side or the suction rod side while engaging with the operating end portion of the positioning claw as the suction rod moves upward. An abutting portion for converging the gripping end portion to the center side is provided, until the abutting portion and the operating end portion of the positioning claw start to come into contact with each other until the gripping end portion converges the workpiece etc. to the central side converging position. The movement range of the working end is approximately 45 degrees with respect to the horizontal line. Suction head device of the workpiece such that characterized by comprising set an angular range of the inner.