JPH1058212A - Chattering vibration preventive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the yield by preventing chattering vibration of a cylindrical member at the time of machining and heighten the roundness and surface roughness of the cylindrical member. SOLUTION: An outer peripheral surface of a cylindrical body 3 is machined while it 3 is rotated around its axis O, and a device to prevent chattering vibration of the body 3 during the machining is configured with a rotary member 1 rotating around the axis O and a plurality of abutting members 2 arranged with possibility of coming in and going out in the radial direction in positions at same intervals on a circumference centering on the axis O at the tip 12 of the rotary member 1, wherein each abutting member 2 receives a resilient force from a spring 21 directed inward radially and will go out radially against the resilient force owing to the centrifugal force when the member 1 is rotating so as to come in contact with the inside surface of the cylindrical body 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a chatter vibration preventing device.

[0002]

2. Description of the Related Art As is well known, a rotary head type magnetic recording / reproducing apparatus has a cylindrical upper cylinder (also referred to as a rotary head cylinder) rotatably and coaxially arranged near a cylindrical lower cylinder. Along the rotation trajectory of the magnetic head fixed to the upper cylinder, the magnetic tape is caused to run at an angle of a predetermined winding angle, and is inclined on the magnetic tape with respect to the edge of the magnetic tape. Information is sequentially recorded and reproduced as a recording trajectory.

[0003] The cylindrical body such as the upper cylinder is formed by, for example, die-casting a metal or pressing a metal plate material. Swells, distortions and irregularities occur on the outer peripheral surface of the body. Therefore, the outer peripheral surface of the cylindrical body is cut to correct the undulation, distortion, and unevenness to increase the roundness and the surface roughness. In the cutting process, a turning tool is applied to the outer peripheral surface of the cylindrical body while rotating the cylindrical body to cut the cylindrical body.

[0004]

At the time of this cutting process, chattering vibration is generated as the cylindrical body tries to escape from the cutting tool due to the cutting resistance of the material constituting the cylindrical body. In particular, chatter vibration is remarkable near the opening of the cylindrical body. When chatter vibration occurs, chatter marks appear on the outer peripheral surface of the cylindrical body.
The upper cylinder with the chatter marks on the outer peripheral surface shifts the center of gravity, causing blur when rotating, and because the outer peripheral surface is not smooth, it damages the tape when winding and running the magnetic tape around this outer peripheral surface. It cannot be used for the rotating head of a recording / reproducing device.

[0005] Further, even in the case of a cylindrical body other than the upper cylinder (for example, a roller or a drum), the one having a chatter mark on the outer peripheral surface at the time of cutting is discarded as a defective product, which causes an increase in cost. An object of the present invention is to prevent chattering vibration of a cylindrical body during cutting, increase the roundness and surface roughness of the cylindrical body, and make it difficult to generate defective products.

[0006]

According to a first aspect of the present invention, there is provided an anti-chattering vibration control apparatus for cutting an outer peripheral surface of a cylindrical body while rotating the cylindrical body around its axis. A device for preventing chatter vibration, comprising: a rotating member adapted to rotate about the axis; and a tip end portion of the rotating member in a radial direction at equally spaced positions on a circumference centered on the axis. And a plurality of contact members arranged so as to be able to enter and exit. The contact members receive an elastic force inward in the radial direction by a spring member. When the rotating member rotates, the contact members come out radially outward against the elastic force due to the centrifugal force, and the inner peripheral portion of the cylindrical body. It comes into contact with the surface.

According to a second aspect of the present invention, in the anti-chattering device according to the first aspect, the distal end surface of the contact member has a curved surface bulging outward so as to substantially follow the inner peripheral surface of the cylindrical body. It is characterized by having. The invention according to claim 3 is the chatter vibration preventing device according to claim 1 or 2,
The tip of the rotating member has a concave portion for accommodating the contact member on the outer peripheral portion, and the contact member is guided in and out in the radial direction by the outer surface along the inner surface of the concave portion. It is characterized by having become.

According to a fourth aspect of the present invention, there is provided the anti-chattering device according to the third aspect, wherein the contact member has a stepped through hole in the center along the radial direction, and the contact member is accommodated in the through hole. The tip of the head rod is attached and fixed to the bottom surface of the rotary member concave portion, and a compression spring is interposed between the head of the rod and the step of the through hole as a spring member.

According to a fifth aspect of the present invention, in the chatter vibration preventing device according to any one of the first to fourth aspects, the rotating member is a chuck device, and the tip of the rotating member is a claw tip of the chuck device. It is characterized by being.

[0010]

When cutting the outer peripheral surface of the cylindrical body while rotating the cylindrical body about its axis, the tip of the rotating member inserted inside the cylindrical body is rotated about the axis. To do. A plurality of abutting members are arranged at the tip of the rotating member so as to be able to enter and exit in the radial direction at equal circumferential positions around the axis. The contact members receive an elastic force inward in the radial direction by a spring member. When the rotating member rotates, the contact members come out radially outward against the elastic force due to the centrifugal force, and the inner peripheral portion of the cylindrical body. It comes into contact with the surface. Therefore, when the rotating member is not rotating, the contact member is in a radially inward direction due to the elastic force, and in this state, the tip of the rotating member can be inserted into the cylindrical body. In addition, when the cylindrical body is rotated around its axis with the tip of the rotating member inserted inside the cylindrical body, the contact member projects radially outward against the elastic force due to centrifugal force. To abut against the inner peripheral surface of the cylindrical body. When the outer peripheral surface of the tubular body is cut with a cutting tool in this contact state, the contact member prevents the tubular body from escaping from the cutting tool and prevents chatter vibration of the tubular body. Therefore, the roundness of the outer peripheral surface of the cylindrical body can be increased by cutting, and the surface roughness (surface roughness) can be improved.
Perfect circular shape with high surface roughness (smooth with little unevenness),
Preferably, a cylindrical body having a perfect circular shape and an outer peripheral surface having a mirror surface can be obtained.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The rotating member of the chatter vibration preventing device of the present invention is adapted to rotate about an axis by, for example, rotation of a rotating shaft of a motor. Then, the contact member is rotated. The tip of the rotating member is inserted into the inside of the cylindrical body to be cut from both openings or one opening. The tip of the rotating member only needs to have an outer diameter smaller than the inner diameter of the cylindrical body to be cut, and the tip of the rotating shaft of the motor, a columnar shape fixed to the rotating shaft,
It may be a tip of a member such as a disk or a tube. The tip of the rotating member can also have a plurality of protrusions extending radially about its axis, in which case abutment members can be attached to these protrusions. Note that the chatter vibration preventing device can be arranged, for example, so that the axis is parallel to the vertical direction or the horizontal direction. It is preferable that the axis is parallel to the vertical direction because the magnitude of the centrifugal force applied to the contact member is uniform.

The chatter vibration preventing device may also serve as a chuck device for holding and rotating the cylindrical body to be cut, or may be separate from the chuck device. When the chatter vibration preventing device also serves as the chuck device, since the rotating member of the chatter vibration preventing device rotates the contact member and the pawl of the chuck device at the same speed in the same direction about the same axis, The axis that is the center of rotation of the contact member coincides with the axis that is the center of rotation of the tubular body, and the control for synchronizing the rotation of the contact member and the tubular body becomes unnecessary. Preferably, a contact member is attached to the pawl of the chuck device.

[0013] When the chatter vibration preventing device is separate from the chuck device, the rotation of the chatter vibration preventing device coincides with the axis centered on the rotation of the chuck device, and is synchronized with the rotation of the chuck device. So that it is controlled. A plurality of contact members are attached to the tip of the rotating member so as to be able to enter and exit in the radial direction. The abutting members are arranged so as to be located at equal intervals on a circumference around the axis at the distal end. The number of the abutting members may be a plurality, but is preferably 2 to 16, particularly 8 in order to make chatter vibration less likely to occur. Each of the plurality of contact members receives an elastic force inward in the radial direction by a spring member. This spring member expands and contracts in the radial direction,
For example, coil springs, leaf springs, rubber materials, air springs,
Such as hydraulic cylinders. When the tip of the rotating member is the claw of the chuck device, the contact member and the spring member are attached to the side of the claw opposite to the cylindrical body holding side.

The attachment of the contact member to the tip of the rotating member is performed, for example, by attaching the contact member to a headed rod and fixing the rod radially outward to the tip of the rotating member. be able to. Also, a plurality of spring members may be attached so as to extend radially from positions on the circumference of the outer peripheral surface of the tip end of the rotating shaft at equal intervals, and abutment members may be attached and fixed to the tip portions of the spring members.
Alternatively, it can be performed by attaching and fixing a spring material inward in the radial direction from outside the contact member. The headed rod is used to prevent the contact member from coming out of the rod when the contact member moves outward in the radial direction. The spring member is disposed between the head of the headed rod and the inner bottom surface of the contact member so as to apply a radially inward elastic force to the contact member. The contact member is accommodated in a concave portion provided so as to open outward on the outer peripheral surface of the distal end portion of the rotating member, and the outer surface of the contact member is guided by the inner surface of the concave portion to enter and exit in the radial direction. Can be. The distal end surface of the abutting member may be a curved surface that bulges outward substantially along the inner peripheral surface of the tubular body. The curved surface is formed, for example, to be a part of a cylindrical surface or a spherical surface having a diameter equal to or smaller than the inner diameter of the cylindrical body. When the contact member is accommodated in the concave portion at the distal end of the rotating member, the distal end surface of the contact member can have a curved surface that matches the outer peripheral surface of the distal end of the rotating member. The headed rod is attached to the bottom surface of the concave portion in a column shape.

The elastic force of the spring member and the centrifugal force at the time of rotation of the rotating member are such that the contact member moves radially outward due to the centrifugal force at a low rotation speed until the rotation speed at the time of cutting is increased. It is preferable to set the relationship such that the body contacts the cylindrical body with a strength that does not deform the body. For example, 3,800r
2,000 rpm when cutting at rpm
The elastic force of the spring member is set so that the contact member moves outwardly and comes into contact with the cylindrical body at the number of rotations. Thereby, the centrifugal force due to the rotation of the rotating member exceeds the elastic force of the spring member, and when the contact member moves radially outward, the centrifugal force gently contacts the inner peripheral surface of the tubular body without strongly colliding with the inner peripheral surface. become.

When cutting the outer peripheral surface of the cylindrical body,
The claws of the chuck device are applied to the cylindrical body, and the cylindrical body is held by the claws. As this chuck device, any device may be used. However, considering that the force applied to each nail is made as small as possible and firmly held, the number of the nails is 2 to 16, particularly 8 One chuck device is preferred. Further, it is preferable to use a diaphragm type chuck device as the chuck device. This is because the diaphragm-type chuck device can firmly hold the cylindrical body with a small force.

At the time of cutting, the tip of the rotating member is inserted into the cylindrical body so that the axis of the rotating member coincides with the axis of the cylindrical body. The cylindrical body is, for example, a cylindrical body, a bottomed cylindrical body having a bottom wall closing one opening, or a double side wall structure having a cylindrical concave portion concentric with the cylindrical side wall inside the cylindrical side wall. And a bottomed cylindrical body. At the time of cutting, the cylindrical body is held and rotated by grasping the outer peripheral surface of the cylindrical body with a pawl of a chuck device. Further, when the rotating member of the chatter vibration preventing device is a chuck device, the bottomed cylindrical body is held by gripping the outer peripheral surface of the cylindrical concave portion of the bottomed cylindrical body having the double side wall structure. The outer peripheral surface can be cut. Examples of the bottomed cylindrical body include an upper cylinder (rotating head cylinder) of a rotating head type magnetic recording / reproducing apparatus such as a video tape recorder and a digital audio tape recorder. The bottomed cylindrical body can be produced by pressing from a metal plate formed in a disk shape, or can be produced by die casting of a metal.

The disc-shaped member is a plastically deformable metal plate (eg, aluminum, aluminum alloy, steel plate, etc.)
The thickness of the disk-shaped member is, for example, not less than 2.5 mm so as not to be broken at the time of press working or to be deformed by the force of a nail gripped at the time of cutting. In the case where the rotating member of the chatter vibration preventing device is a chuck device, when the pawl is inserted into the cylindrical body having the double side wall structure and grasps the outer peripheral surface of the cylindrical concave portion of the cylindrical body, the pawl is formed. A projection can be provided on the distal end surface of the claw in order to abut the bottom wall of the cylindrical body. When this projection is in contact with the bottom wall of the tubular body, the tubular body is more stably held. The projection is not particularly limited, but may be, for example, an annular projection or an arc-shaped projection centered on the axis.

[0019]

Embodiments of the present invention will be described below with reference to the drawings, but the embodiments of the present invention are not limited to the following embodiments. (Embodiment 1) FIG. 1 is an enlarged sectional view of a main part of a chatter vibration preventing device according to Embodiment 1. FIG. 2 is an enlarged front view of the chatter vibration preventing device. The part on the right side of the member indicated by 11 in FIG. 1 shows a YY cross section in FIG.

This chatter vibration preventing device includes a diaphragm type chuck device 1 as a rotating member. The diaphragm-type chuck device 1 has eight claws 12 attached to an outer surface of a diaphragm 11. This attachment is performed by fastening the pawl 12 with a bolt 13 to a pedestal 110 provided on the outer surface of the diaphragm 11. As shown in FIG. 2, the eight pawls 12 are arranged at equal intervals on the circumference centered on the axis O. This axis O extends in the horizontal direction. By making the internal pressure in the inner space on the back surface side of the diaphragm 11 the same as the external pressure on the outside of the diaphragm 11 (the state shown in FIG. 1), the tips of the eight claws 12 narrow toward the axis O. Thus, the tubular body can be held when this contraction occurs. Figure 1,
Reference numeral 2 indicates this collapsed state.

As shown in FIG. 1, the pawl 12 is a member having a substantially F-shaped cross section and side surfaces.
3 is installed so as to face outward. The lower lateral portion 121 of the pawl 12 has a hole 122 that receives the head of the bolt 13 and through which the shaft of the bolt 13 passes. Nail 12
The upper lateral side 123 has a recess 12 for accommodating the contact member 2.
4 are formed so as to open outward.

The contact member 2 has a stepped through hole 201 at the center as shown in an exploded perspective view in FIG. The through hole 201 has a step portion 202 for receiving the coil spring 21 mounted on the headed rod 22 and a fine hole portion 203 through which the tip of the rod 22 penetrates. The shaft portion of the bolt 23 that has penetrated the headed rod 22 also penetrates the through hole 201 of the contact member 2, and is provided on the bottom surface of the concave portion 124 on the upper side of the pawl 12 as seen in FIGS. The screw hole 125 is adapted to be screwed. Thereby, the contact member 2 is attached to the pawl 12, and the coil spring 21 is a compression-type spring, and the flange portion 221 of the headed rod 22.
And a step portion 202 of the through hole 201, and applies an elastic force to the contact member 2 toward the bottom surface of the concave portion 124 of the pawl 12. The distal end surface 204 of the contact member 2 is curved so as to form a cylindrical surface with the distal end surface of the upper lateral side portion 123 of the pawl. 4 and 5 show a WW section of FIG.

As shown in FIG. 1, the abutment member 2 has a pawl 12
And the diaphragm 11 is pushed out to the right (in the direction opposite to the arrow) in FIG. 1 by increasing the pressure (internal pressure) in the internal space of the diaphragm 11 to be higher than the external pressure (external pressure). In the state of being caught, the claw 12 of the chuck device 1
Is inserted into the bottomed cylindrical body 3 and the diaphragm 11 is inserted.
The inner pressure is released and the diaphragm 1 is returned to the left (in the direction of the arrow) (return to the state shown in FIG. 1), so that the tips of the eight claws 12 are reduced toward the axis O and the bottomed cylinder The outer peripheral surface of the cylindrical side wall 38b of the cylindrical concave portion 38 of the body 3 is firmly gripped by a weak force. In this gripped state, the chuck device 1 is rotated about the axis O to cut the outer peripheral surface of the cylindrical side wall 37 of the bottomed cylindrical body 3 with the cutting tool 90.

The bottomed cylindrical body 3 is formed by pressing an aluminum alloy disk-shaped member to raise the outer peripheral edge of the disk-shaped member, thereby forming a cylindrical side wall 37 and the cylindrical side wall 3.
And a bottom wall 39 closing one opening of the bottom wall 7.
Is formed so as to extend concentrically with the cylindrical side wall 37 at the center portion thereof and to project a cylindrical concave portion 38 inward by press working or the like.

As shown in FIGS. 1, 2 and 4, when the tubular body 3 is gripped by the pawl 12 and is not rotating, the contact member 2 (shown by a broken line in FIG. 2) is housed in the concave portion 124 of the pawl 12. There is a gap between the cylindrical side wall 37 of the cylindrical body 3 and the contact member 2. When the chuck device 1 is rotated about the axis O, the cylindrical body 3 also rotates about the axis O as shown in FIGS. Due to the centrifugal force of rotation of the chuck device 1, the eight contact members 2 (indicated by dashed lines in FIG. 2) move outward against the elastic force of the coil spring 21 and project from the concave portion 124 to form a cylindrical shape. Side wall 3 of body 3
7 comes into contact with the inner peripheral surface. When the contact member 2 moves, the outer surface of the contact member 2 is guided to the inner surface of the concave portion 124 of the pawl 12. When the outer peripheral surface of the side wall 37 of the cylindrical body 3 is cut with the cutting tool 90 in a state where the contact member 2 is in contact with the inner peripheral surface of the cylindrical body 3, the side wall 37 of the cylindrical body 3 is turned inward by the cutting tool 90. Even if it is pressed, since the contact member 2 is pressing from the back side, the side wall 37 cannot escape from the cutting tool 90, and almost or no chatter vibration is generated.

By this cutting, the side wall 37 of the cylindrical body 3 is formed.
Can be a mirror surface with no chatter marks or holes and a perfect circular shape centered on the axis O and having a surface roughness of about 0.3S. This cut cylindrical body 3 is preferably used as a rotary head cylinder. As shown in FIGS. 1 and 2, an arc-shaped projection 126 centering on the axis O is formed on the distal end surface of the pawl 12, and the pawl 12 is
The arc-shaped projection 126 is also in contact with the bottom wall 39 of the cylindrical body 3 when inserted into the inside of the cylindrical body and grasping the outer peripheral surface of the cylindrical concave portion 38. Thereby, the cylindrical body 3 is held more stably.

(Embodiment 2) FIG. 6 shows an embodiment in which the contact member of the chatter vibration preventing device of the present invention is formed separately from the pawl of the chuck device. In this embodiment, the rotating member of the chatter vibration preventing device may be a chuck device or may be a separate device from the chuck device. FIG. 7 is a sectional view taken along line VV of this embodiment, and FIG. 6 is a sectional view taken along line ZZ of FIG. In this chatter vibration preventing device, the rotating shaft 150
A concave portion 124 is formed in the outer peripheral portion of the disk 100 attached to the bolts 151 as in the first embodiment. The contact member 2 is accommodated and mounted in the concave portion 124 as in the first embodiment. Receiving inward elastic force. 125 designates the contact member 2 as the disk 1
It is a screw hole for screwing a bolt (not shown) for attaching to 00. The distal end surface of the contact member 2 is curved so as to form a cylindrical surface with the outer peripheral surface of the disk 100.

As shown in FIG. 6, a cylindrical body 30 having both openings is provided.
The cylindrical body 30 is held by grasping the outer peripheral surface at one end of the cylindrical body with the claws 830, and the disk 100 of the chatter vibration preventing device is inserted and positioned inside the other end of the cylindrical body 30. At this time, the contact member 2 is housed in the concave portion 124 of the disk 100. Then, in this state, the pawl 8
A chuck device having 30 (not shown. This chuck device is, for example, a diaphragm type chuck device).
The disk 100 is rotated around the axis O in the same direction and at the same speed, and the outer peripheral surface of the cylindrical body 30 is cut by the cutting tool 90. This axis O extends in the horizontal direction. When the disc 100 rotates, the outer side surface of the contact member 12 is guided by the inner side surface of the concave portion 124 and moves outward, and protrudes as shown by a dashed line in FIGS. The distal end surface contacts the inner peripheral surface of the cylindrical body 30. For this reason, at the time of cutting, even if the cylindrical body 30 is pressed inward by the cutting tool 90, the cylindrical member 30 cannot escape from the cutting tool 90 and generates little or no chatter vibration because the contact member 2 is pressed from the back side. No longer.

As a result of this cutting, the outer peripheral surface of the cylindrical body 30 is a mirror surface with no chatter marks or holes and a perfect circular shape having a high surface roughness centered on the axis O (preferably a perfect circular shape with no irregularities). ). The cut cylindrical body 30 is preferably used as a disk spacer, a drum, a roller, or a pinch roller.

[0030]

As described above, according to the present invention, chatter of the cylindrical body during cutting is prevented, the roundness and surface roughness of the cylindrical body are increased, and defective products are less likely to occur. Will be done.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view showing a main part of a chatter vibration preventing device according to a first embodiment of the present invention.

FIG. 2 is an enlarged front view of the chatter vibration preventing device.

FIG. 3 is an enlarged perspective view, partly in section, showing an attached state of a contact member.

FIG. 4 is a partially enlarged cross-sectional view showing a state in which a tip end of a rotating member of the chatter vibration preventing device is inserted into a cylindrical body.

FIG. 5 is a partially enlarged cross-sectional view showing a state in which a tip end of a rotating member of the chatter vibration preventing device is inserted into a cylindrical body and rotated.

FIG. 6 is an enlarged sectional view showing a main part of a chatter vibration preventing device according to a second embodiment of the present invention.

FIG. 7 is an enlarged sectional view of the chatter vibration preventing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chuck apparatus 2 Contact member 3 Cylindrical body with a bottom 12 Claw 21 Coil spring 22 Headed rod 30 Cylindrical body 124 Depression 221 Flange part O-axis

Claims (5)

[Claims] 1. An apparatus for preventing chatter vibration of a tubular body when cutting an outer peripheral surface of the tubular body while rotating the tubular body about the axis thereof, the apparatus comprising: A rotating member that is adapted to rotate, and a plurality of abutting members that are arranged so as to be able to enter and exit in the radial direction at equally spaced positions on the circumference around the axis at the tip of the rotating member. The contact member is configured to receive an elastic force in a radially inward direction by a spring member. When the rotating member rotates, the contact member comes out radially outward against the elastic force by centrifugal force. Characterized in that it comes into contact with the inner peripheral surface of the cylindrical body,
Anti-vibration device. 2. The chatter vibration preventing device according to claim 1, wherein a distal end surface of the contact member has a curved surface bulging outward so as to substantially follow an inner peripheral surface of the cylindrical body. 3. An end portion of the rotating member has a concave portion for accommodating the contact member in an outer peripheral portion, and the contact member includes:
The chatter vibration preventing device according to claim 1 or 2, wherein the outer surface is guided along the inner surface of the concave portion so as to guide the entry and exit in the radial direction. 4. The contact member has a stepped through-hole at the center along the radial direction, and a tip of a headed rod housed in the through-hole is fixedly attached to a bottom surface of the rotating member recess, The chatter vibration preventing device according to claim 3, wherein a compression-type spring is interposed between the head of the rod and a step portion of the through-hole as the spring member. 5. The chatter vibration preventing device according to claim 1, wherein the rotating member is a chuck device, and a tip of the rotating member is a tip of a nail of the chuck device.