JPH03170210A - Holding device for cutting umbrella surface - Google Patents

Abstract

PURPOSE:To cut a head part umbrella surface of an umbrella-shaped work effectively at a high umbrella thickness precision by tightly applying an aligning member and an umbrella back receiving member to an umbrella-shaped head part of the work for improving the rigidity of the head part in cutting. CONSTITUTION:When a shaft part 14 of a work 40 is grasped by a chuck metal 7, the work 40 is regulated for the position of an umbrella back 43 by the front end part of a chuck 2. Next, a pressure member 51 of an inserting means 50 is moved to retract, and an electromagnetic changing valve 33 of a fluid pressure supply means 30 is put on, so a supplied air pressure presses an aligning member 15 and an umbrella back receiving member 18 on the back surface side through a rotary coupling 32 and a draw bar 31 in the chuck 2. The aligning member 15 and the umbrella back receiving member 18 are integrated by this pressure to be tightly applied to the umbrella back 43 of the work 40 so as to improve the rigidity of a head part 42. A main shaft 1 is then driven, and the work 40 is rotated through the chuck 2, and a cutting means 55 is actuated, thereby the surface of an umbrella surface 44 of the work 40 is cut by a blade 58.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a holding device for cutting an umbrella surface used for cutting the head surface of an umbrella-shaped workpiece.

<Prior Art> Conventionally, an umbrella-shaped workpiece formed by forging or the like, for example, an automobile engine valve as shown by workpiece 40 in FIG. The head 42 is formed by heating, plastic deformation, etc. This workpiece 4
0's head 42 is made by cutting the 44 sides of the umbrella surface after removing distortion.
It was intended to maintain the accuracy of the umbrella thickness of the head 42. In addition, 43 in the figure is the umbrella back, and the thickness between the umbrella back 43 and the umbrella front 44 is called umbrella thickness.

Generally, cutting of the umbrella face 44 of such an umbrella-shaped workpiece 40 has been carried out by gripping the shaft portion 41 with a chuck provided on the main shaft of a lathe or the like.

FIG. 7 is a sectional view showing a state where the shaft portion 41 of the workpiece 40 is gripped by the chuck 2 for cutting the umbrella surface.

The chuck 2 shown in FIG. 7 is provided inside a substantially cylindrical body 3 and includes a taper sleeve 4 and a collet 6 that are movable in the axial direction. A tapered portion 4a at the tip of the tapered sleeve 4 engages with the outer periphery of the collet 6 to reduce the diameter of the collet 6, and the chuck fitting 7 grips the shaft portion 41. Incidentally, as a known technique related to such a chuck, for example, Japanese Utility Model Publication No. 1983
There are those described in Japanese Utility Model Publication No. 6003 and Japanese Utility Model Publication No. 62-8966.

Problems to be Solved by the Invention> However, as shown in FIG.
When gripped by the chuck 2, the head 42 is in a state floating above the tip of the chuck 2.

Therefore, when the umbrella surface 44 is cut, distortion occurs due to cutting resistance, and chatter is likely to occur on the machined surface. Therefore, it was necessary to reduce the cutting speed or reduce the nose radius of the cutting tool.

Further, the purpose of cutting the umbrella surface of the workpiece 40 such as an engine valve is to prevent interference with other parts during use.
and securing the perpendicularity of the umbrella face 44 to the shaft portion 41, as well as defining the umbrella thickness dimension. However, even if the workpiece 40 is strain-removed after forming, there remains a slight wobbling of the head 42 and a slight distortion of the shape of the umbrella back 43.
3 was difficult to maintain uniformly and use as a processing standard. Therefore, in the past, the cutting allowance of the canopy table 44 was determined based on the canopy table standard, which resulted in a problem of large variations in the canopy thickness dimension.

This invention was made in order to solve the above-mentioned problems, and provides an umbrella surface that can efficiently cut the head cap surface of an umbrella-shaped workpiece, and can also cut the head cap surface of an umbrella-shaped workpiece with high precision in the cap thickness. The object of the present invention is to provide a holding device for cutting.

Means for Solving the Problems This invention has been made to achieve the above object, and includes a chuck that is fixed to the main shaft of a machine tool and rotates, and is provided at the front end of the chuck to hold an umbrella-shaped workpiece. A holding device for cutting an umbrella surface, which includes a mounting plate that shares an axis with the chuck and has a through hole in the center, and is provided at the front end of the body of the chuck, and a mounting plate that shares an axis with the chuck and extends toward the front side of the body of the chuck. an alignment member having an enlarged diameter conical hole passing through the mounting plate, the alignment member being movable in the radial direction on the front side of the mounting plate; and the alignment member being provided on the front side of the alignment member and engaging with the conical hole. It has a conical part, and has a through hole passing through the center of the conical part, and a front opening of the through hole is attached to the back of the umbrella-shaped head of the workpiece. The umbrella back support member is provided with an abuttable umbrella back contacting part, and the umbrella back support member can be supported while maintaining airtightness through an O-ring made of an elastic material and fixed to the mounting plate. A flange member provided therein, a hollow drawbar penetrating the inside of the main shaft and having a front end opening in the body of the chuck, and a rotary joint capable of supplying fluid pressure into the drawbar, the centering member and This is a holding device for cutting an umbrella front surface, which includes a fluid pressure feeding means that is capable of pressing the rear surface side of an umbrella back support member using fluid pressure.

Effect> The present invention is configured as described above, and the umbrella back support member prevents distortion of the umbrella back shape by bringing the umbrella back of the umbrella shaped head of the workpiece into close contact with the umbrella back contact portion. move in the radial direction according to Further, the centering member moves in the radial direction via the umbrella back support member according to the surface deflection of the umbrella-shaped head to position the umbrella back. The flange member absorbs movement of the umbrella back support member in the radial direction via the O-ring, and supports the umbrella back support member while maintaining airtightness.

The fluid pressure feeding means supplies fluid pressure to the rear side of the aligning member and the umbrella back support member, presses them to the back of the umbrella of the workpiece held by the chuck, and brings them into close contact with the back of the workpiece. The umbrella-shaped head is made highly rigid.

<Embodiment> An embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

Fig. 1 is a cross-sectional view of the overall configuration of a holding device for cutting an umbrella face of the present invention, and Fig. 2 is an enlarged sectional view of its main parts.This holding device for cutting an umbrella face is fixed to the main shaft 1 of a machine tool such as a lathe. The mounting plate 11 and the conical hole 16 provided on the front end of the body 3 of the chuck 2 are equipped at the front end of the chuck 2.
, and the front side of the mounting plate 11 (the right-hand side in Fig. 2)
An umbrella back support member 1 having an alignment member 15 that is movable in the radial direction, a conical portion 19, and an umbrella back contact portion 21.
8, a flange member 25 that is fixed to the mounting plate 11 and supports the umbrella back support member 18 via an O-ring 29, a hollow drawbar 31, and a rotary joint 32, and a fluid pressure feeding means that supplies fluid pressure. 30.

The chuck 2 in this embodiment is similar to the conventional example, and more specifically, it includes a cylindrical body 3 fixed to the main shaft 1 and rotating, and a chuck 2 that is movable in the axial direction in contact with the inner diameter of the body 3. The tapered sleeve 4 has a tapered part 4a on the inner peripheral side of the front end, and the tapered part 6a that engages with the tapered part 4a of the tapered sleeve 4 on the outer periphery of the front end, and the front end is divided into three by slotted grooves to form a tapered sleeve. 4
A collet 6 is disposed with its axis aligned with the inner diameter of the collet 6, and a plurality of chuck fittings 7 are provided on the inner circumferential side of the divided front end of the collet 6 and are capable of gripping the shaft portion 41 of the workpiece 40. It is equipped with

A connecting member 8 is attached to the rear end of the taper sleeve 4, and the connecting member 8 is connected to a hollow drawbar 31 that is disposed to penetrate inside the main shaft 1. The front end opening of the drawbar 31 is connected to the through hole 8a of the connecting member 8.
The axial movement of the draw bar 31 pushes and pulls the Taber sleeve 4, and the chuck fitting 7 of the collet 6 grips or grips the shaft portion 41 of the workpiece 40. It is configured to perform that release.

The mounting plate 11 is made of a substantially annular member having a through hole 12 in the center thereof, and is fixed to the front end of the body 3 with a plurality of bolts 13 .

The alignment member 15 is formed into a cylindrical body having a brim-like flange portion 15a on the front side, and the inner peripheral surface is formed as a conical hole 16 whose diameter increases toward the front side. The alignment member 15 is loosely fitted into the through hole 12 of the mounting plate 11, and the flange portion 15a is disposed along the front side of the mounting plate 11 so as to be movable in the radial direction.

The umbrella back support member 18 has a conical hole 16 of the centering member 15 on one side.
A conical part 19 is provided which engages the conical part 1.
A through hole 22 is drilled through the center of the through hole 2.
An umbrella back abutment part 21 formed in the shape of a conical hole is provided at the front opening of the umbrella 2. In the embodiment, the conical portion 19 has an outer wall whose vertical cross-sectional shape is an outwardly bulging arcuate curve, and is shaped so as to abut and engage with the surface of the conical hole 16. Further, the through hole 22 has a diameter that allows the shaft portion 41 of the workpiece 40 to be loosely fitted therein.
The umbrella back contact portion 21 is formed to make surface contact or line contact with a portion near the outer periphery of the umbrella back 43. Furthermore, the flange member 25 is formed on the outer periphery of the umbrella back support member 18 so that an O-ring 29 can be fitted therein, and a flange portion 18a for preventing the umbrella back support member 18 from coming off is formed. It is formed in an annular shape and is fixed to the mounting plate 11 with a plurality of bolts 28. A ring receiving portion 26 is formed on the inner peripheral side of the flange member 25 to receive an O-ring fitted to the umbrella back receiving member 18 and to prevent the O-ring from slipping outward.

The O-ring 29 is heat resistant. It is made of an oil-resistant elastic material, and is interposed between the umbrella back support member 18 and the flange part 25 to maintain airtightness between the two, and to protect the umbrella back support member 18 from its It is formed to absorb and support radial movement.

In the umbrella back support member 18 supported by the flange member 25, the umbrella back abutment member 21 is located on the front side of the umbrella front cutting holding device, and the axis of the through hole 22 substantially coincides with the axis of the chuck 2. It is arranged so that At this time, the conical hole 16 of the alignment member 15 and the conical portion 1 of the umbrella back support member 18
9, the alignment member 15 is in a substantially free state in which it can move a certain amount along the mounting plate 11.

The fluid pressure supply means 30 is composed of a hollow drawbar 31 and a rotary joint 32 that communicate with the inside of the chuck 2, and an electromagnetic switching valve 33 that is connected to an air pressure source as fluid pressure and controls the supply of air pressure into the chuck 2. has been done.

Then, when air pressure is supplied to the rotary joint 32 under the control of the electromagnetic switching valve 33, the air pressure is supplied to the inside of the chuck 2 via the draw bar 31.

Further, the air pressure is formed to reach the rear side of the alignment member 15 and the umbrella back support member 18 through the slotted groove at the tip of the collet 6, and press them toward the front side in the axial direction of the jack 2. There is.

Furthermore, a hollow cylinder 35 that can push and pull the draw bar 31 in the glaze direction is equipped on the outer peripheral side of the draw bar 31.
The hollow cylinder 35 is configured to be controlled by an electromagnetic switching valve 36 connected to an air pressure source.

The workpiece 40 is preferably inserted into the holding device for cutting the umbrella surface by an insertion means 50 that includes a suppression member 51 having a suppression piece 51a axially biased by a spring 51b. (See Figure 3). This suppression member 51 moves forward and backward by a cylinder 52 controlled by an electromagnetic switching valve 53.
When the shaft portion 41 of the workpiece 40 is inserted into the chuck 2 in the released state, the head portion 42 is pressed by the spring force of the spring 51b, and the umbrella back 43 is brought into contact with the umbrella back contact portion of the umbrella back support member 18. Furthermore, a cutting stage 55 equipped with a cutting tool 58 is provided on the front side of the holding device for cutting the canopy surface. This cutting means 55 includes a cylinder 56 controlled by an electromagnetic switching valve 59.
The cutting tool 58 is configured to be able to cut the umbrella surface 44 of the workpiece 40 by moving forward or backward (see FIG. 5).

The electromagnetic switching valves 33, 36, 53, 59, etc. are connected to a control device (not shown) and are configured to perform predetermined control operations.

Next, the operation of the holding device for cutting the umbrella face constructed as described above will be explained.

First, in the standby state of the device, the hollow cylinder 35 is controlled by the electromagnetic switching valve 36 to pull the drawbar 31 to the left in FIG. 1, thereby releasing the collet 6 and expanding the diameter of the chuck fitting 7. . In addition, the electromagnetic switching valve 33 cuts off air pressure supply, and the alignment member 15 and the umbrella back support member 1
8 is in a substantially free state in which it can move along the mounting plate 11.

In this state, the shaft portion 41 of the workpiece 40 is inserted into the through hole 22 of the umbrella back support member 18, and further inserted into the inner peripheral side of the chuck fitting 7 of the chuck 2.

Next, the insertion means 50 is operated, and the pressing piece 5 of the pressing member 51 is
1a presses the umbrella surface 44 of the workpiece 40 via spring force (see FIG. 3). As a result, a portion of the workpiece 40 near the outer periphery of the umbrella back 43 comes into contact with the umbrella back contact portion 21 of the umbrella back support member 18 .

At this time, if there is a distortion in the shape of the umbrella back 43, the umbrella back support member 18 moves in the radial direction according to the distortion, and the umbrella back 43 is moved in the radial direction.
3 and the umbrella back contact part 21 are in surface or line contact, and the umbrella front 44 surface is in contact with the umbrella back support member 18.3. It protrudes slightly forward from the front side of the flange member 25.

In addition, as the umbrella back 44 is pressed, the conical portion 19 of the umbrella back support member 18 abuts and engages with the conical hole 16 of the alignment member 15, and presses the alignment member 15, causing the mounting plate 11 to Insert it between. At this time, the surface runout of the head 42 is perceived as a movement of the alignment member 15 in the radial direction.

Next, the hollow cylinder 35 is controlled to push the drawbar 31 to the right, the chuck 2 is tightened, and the chuck fitting 7 is used to push the shaft portion 4 of the workpiece 4o.
Perform 1 grip. Thereby, the position of the umbrella back 43 of the workpiece 40 is defined at the front end of the chuck 2.

Next, the pressing member 51 of the landing means 50 is moved backward, and the electromagnetic switching valve 33 of the fluid pressure feeding means 3o is turned on to supply air pressure. This air pressure is applied to the rotary joint 32. Inside the chuck 2 via the trow bar 31, the rear sides of the alignment member 15 and the umbrella back support member 18 are pressed. By this pressing, the alignment member 15 and the umbrella back support member 18 are brought into close contact with the umbrella back 43 of the workpiece 40 as one body, and the rigidity of the head 42 is improved. Further, the O-ring 29 prevents the air pressure from leaking (see FIG. 4).

Subsequently, the main shaft 1 is driven to rotate the workpiece 40 via the chuck 2. Then, the cutting stage 55 is operated to cut the umbrella surface 44 of the workpiece 40 using the cutting tool 58 (see FIG. 5).

In this cutting process, a cutting allowance is set based on the surface contact or line contact line between the umbrella back contact part 21 and the umbrella back 43 as a processing reference.

That is, even if there is a deflection of the head 42 or a distortion of the umbrella back 43,
Umbrella back support member 18. By moving the alignment member 15 in the radial direction, the umbrella back contact portion 21 and the umbrella back 43 are brought into proper contact with each other, and the umbrella back 4
By performing the positioning described in step 3, the contact area can be used as a processing reference. Therefore, it is only necessary to consider the amount of wear of the cutting tool 58 for the cutting allowance, and the accuracy of the cap thickness can be improved.

Table 1 Table 1 shows an example of the cutting conditions for the workpiece 40 cut by this umbrella cutting holding device in comparison with a conventional example. Note that the workpiece 40 subjected to cutting has a shaft portion 41
The diameter of the head 42 is 8 mm, the diameter of the head 42 is 45}, and the total length is 1
It is 08mm.

As shown in Table 1, by using the holding device for cutting the canopy surface according to the present invention, cutting is performed using a dog-shaped cutting tool 58 with a radius of nose and at a high spindle speed, thereby reducing the degree of surface roughness. In addition to being able to suppress the thickness of the umbrella, it was also possible to suppress variations in the thickness of the umbrella to a low level.

When the cutting of the umbrella face 43 is finished, the cutting tool 58 is moved back and the rotation of the main shaft 1 is stopped. Further, the supply of air pressure by the fluid pressure supply means 30 is cut off, the drawbar 31 is retracted by the hollow cylinder 35, the collet 6 is released, and the diameter of the chuck fitting 7 is expanded. Then, the workpiece 40 is taken out from the chuck 2, and all steps of one cycle are completed.

Note that this invention is not limited to the above description and illustrated examples, and its embodiments can be changed without departing from the technical idea of this invention. for example,
It goes without saying that the shape of the umbrella back contacting part -17- of the umbrella back support member can be freely set in accordance with the shape of the umbrella back of the workpiece.

<Effects of the Invention> As explained above, the umbrella face cutting holding device of the present invention has the following advantages:
A holding device for umbrella surface cutting that is installed at the front end of a chuck that is fixed to the main shaft of a machine tool and rotates to hold an umbrella-shaped workpiece, which shares the chuck axis and has a through hole in the center. It has a mounting plate provided at the front end of the chuck body, a conical hole in the center that extends toward the front side, and is movable in the radial direction on the front side of the mounting plate. a member, a conical part provided on the front side of the alignment member and engaged with the conical hole, and a through hole passing through the center of the conical part, and on the front side of the through hole. An umbrella back support member is provided with an umbrella back contacting part that can come into contact with the umbrella back of the umbrella-shaped head of the workpiece at the opening, and an umbrella is fixed to the mounting plate through an O-ring made of an elastic material. A flange member installed to be able to support the backing member while maintaining airtightness, a hollow drawbar that penetrates the inside of the main shaft and has a front end opening in the body of the chuck, and the drawbar. Since the configuration includes a rotary joint capable of supplying fluid pressure to the inside, and a fluid pressure feeding means provided to be able to press the rear side of the alignment member and the umbrella back support member with fluid pressure, the alignment member and The umbrella back support member is brought into close contact with the umbrella-shaped head of the workpiece by fluid pressure, increasing the rigidity of the head and making it possible to perform cutting.

Therefore, it is possible to suppress the occurrence of distortion due to cutting resistance and prevent the occurrence of chatter on the machined surface.As a result, cutting can be performed at a high spindle rotation speed, and it is possible to cut with a relatively large nose radius. , can be cut efficiently.

In addition, the umbrella back support member and alignment member move in the radial direction according to minute distortions in the shape of the umbrella back of the workpiece and surface runout of the head, respectively, so that the umbrella back can be positioned accurately. can.

Therefore, when machining the cap surface of the workpiece, the cutting allowance can be determined using the cap back side as a processing reference, reducing the factors that cause variations in the cap thickness dimension, and making it possible to perform cutting while maintaining high cap thickness accuracy. Make the most of your efforts.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the overall configuration of a holding device for cutting an umbrella surface according to an embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of the main part, and FIG. 3 is an explanatory view showing a state in which a workpiece is inserted. Figure 4 is an overall explanatory diagram with the workpiece inserted, Figure 5 is an explanatory diagram showing the cutting state, Figure 6 is a side view of an example of the workpiece, and Figure 7 is the conventional example. FIG. 3 is an explanatory diagram showing a grip state of a workpiece. 2... Chuck, 11... Mounting plate, 15... Centering member, 16... Conical hole, 18... Umbrella back support member, 19... Conical part, 21... Umbrella Back contact portion, 5... Flange member, 9... O-ring, O... Flow-reduction pressure feeding means, 0... Workpiece. Patent applicant Aisan Kogyo Co., Ltd. 2 1 S↑

Claims (1)

[Scope of Claims] A holding device for cutting an umbrella surface, which is provided at the front end of a rotating chuck that is fixed to the main shaft of a machine tool and holds an umbrella-shaped workpiece, the holding device sharing an axis with the chuck and having a central a mounting plate provided at the front end of the body of the chuck and having a through hole in the front end thereof; an alignment member provided movably in a radial direction; and a conical portion provided on the front side of the alignment member and engaged with the conical hole, and having a central portion of the conical portion. an umbrella back receiving member having a through hole passing through the hole and having an umbrella back contacting part that can come into contact with the umbrella back of the umbrella-shaped head of the workpiece at the front side opening of the through hole; a flange member that is fixedly attached and capable of supporting the umbrella back support member while maintaining airtightness through an O-ring made of an elastic material; A fluid pressure feeding means comprising a hollow drawbar opened inward and a rotary joint capable of supplying fluid pressure into the drawbar, and provided to be able to press the rear side of the centering member and the umbrella back support member with fluid pressure. A holding device for cutting an umbrella surface, comprising: and.