JPH02205409A - Movable blade main body holding structure for cutter - Google Patents

Abstract

PURPOSE:To prevent rotation of a movable blade main body, and looseness thereof so as to prevent the generation of cracks in the movable blade main body and a holder by fitting the movable blade main body into the holding hole of the holder at an ordinary temperature, fitting a coupling ring into the recessed groove of both members to be plastically deformed. CONSTITUTION:A movable blade main body 21 is fitted into the holding hole of a holder at an ordinary temperature and temporarily coupled. In the coupling part of both members, annular step parts 21h, 22h for forming an annular groove 24 into which a coupling ring 23 is inserted are formed. On the constituting faces of the respective step parts 21h, 22h, a plurarity of rows of V shaped circumferential recessed grooves 21d, 22d are formed. Further, axially recessed grooves 21e, 22e are formed at every prescribed pitch in directions orthogonal to the grooves 21d, 22d and protruding parts 21f, 22f are integrally formed at the axially inner edges of the respective step parts 21h, 22h. In this groove 24, a coupling ring 23 made of metal is inserted under pressure, plastically deformed by the protruding parts 21f, 22f and coupled and held, so that no crack is produced due to fitting at an ordinary temperature and the rotation or the looseness of the movable blade main body 21 can be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a high-speed shear cutting machine typified by a percussion cutting machine, and in particular, the movable blade main body can be pulled out and rotated reliably, and The present invention relates to an improvement in a holding structure for a movable blade body that can prevent the movable blade body and a holder holding the same from cracking due to impact force.

[Conventional technology]

The above-mentioned impact cutting machine has a fixed blade and a movable blade that can be moved up and down facing each other, inserts the material to be cut into the through holes of both blades, and in this state moves the movable blade at high speed using impact force. Shears the material to be cut.

This is a device that cuts by a combination of breaks.

An example of a conventional impact cutting machine is shown in FIGS. 5 to 7.

In the figure, 1 is an impact cutting machine, which mainly consists of a base 2 fixed on a pedestal 2a fixed on a foundation, a fixed blade 3 disposed on the base 2, and a fixed blade 3 disposed on the base 2. a positioning part 4 for positioning, a movable blade 5 arranged to be movable up and down, a cutting length setting part 6 for defining the cutting length of the material to be cut (hereinafter referred to as work) W, and a blow to the movable blade 5. It is comprised of a striking device 7 that applies force and defines the vertical stroke of the movable blade 5.

The fixed blade 3 has a cylindrical shape having a guide hole 3a at its axis, and is fixed on the base 2 via a holder 3b. Note that 3d is a compressed air passage for discharging the cut portion of the workpiece W. Further, the positioning portion 4 is formed by screwing a bolt member 4b into a nut member 4a fixed to the base 2, and when the bolt member 4b is rotated, its tip moves the fixed blade 3 forward.

The movable blade 5 is held on the base 2 by a holder 5a so as to be movable up and down, and has a structure in which the movable blade body 9 is inserted and fixed into a holding hole 8a formed in the center of the holder 8 by shrink fitting. ing.

This movable blade body 9 is disc-shaped, and has a through hole 9 at its axis.
a is formed, and a U-shaped escape groove 9b is formed on the back side.
is formed. Further, the holder 8 is a rectangular flat plate, and has a convex portion 8b formed on the upper edge and the holding hole 8a.
An escape groove 8C is formed at the edge of the groove 8C, which extends upward so as to be continuous with the escape groove 9b. These escape grooves 9b, 3c
This is to prevent the movable blade 5 from interfering with a stopper, which will be described later, when the movable blade 5 descends.

The cutting length setting section 6 inserts a piston rod 11 into a cylinder 10 fixed on the base 2, inserts a detection rod 12 into the loft 11 so as to be slidable in the axial direction,
The detection iron 12 has a structure in which a stopper head 13 is fixed to the front end thereof to abut the tip of the workpiece W to position the workpiece W. Further, a proximity switch 14 is disposed at the rear end of the piston rod 11 so as to face the rear end of the detection rod 12 . A nut member 15 is threaded onto the rear portion of the piston rod 11, and by rotating the nut member 15, the forward end position of the piston rod 11 can be adjusted.

The striking device 7 includes an air hammer 16 for striking the convex portion 8b of the holder 8, and a cushion 17 consisting of an air cylinder and a hydraulic damper. is supported at a height that matches the guide hole 3a, and the downward stroke of the holder 8 due to the impact force is regulated to a predetermined value while buffering the impact force.

During the cutting operation using the conventional impact cutting machine 1, when the workpiece W is advanced by a feed mechanism (not shown), its tip comes into contact with the stopper head 13, the head 13 moves back slightly together with the detection rod 12, and the proximity switch 14 outputs a workpiece detection signal to the striking device 7. Then air hammer 1
6 hits the holder 8, the movable blade 5 descends and cuts the work W, and the cut work is transferred to the compressed air passage 3.
The high pressure air from d is discharged to the back side of the movable blade 5. Further, at this time, since the stopper head 13 is located within the escape grooves 9b and 8c of the movable blade 5, it will not interfere with the movable blade 5 even if it descends.

[Problem that the invention seeks to solve]

In the above conventional impact cutting machine 1, the holder 8. There is a problem in that cracks C occur in the movable blade main body 9, especially in the escape groove 8c at the edge of the holding hole 8d, and the life of the movable blade 5 is shortened.To prevent the above-mentioned crank and extend the life of the movable blade. is requested.

The present inventors conducted experimental research to discover the cause of cranking in the holder of the above-mentioned conventional device, and found that the major cause lies in the structure in which the movable blade body is fitted and held in the holder by shrink fitting. . That is, in the case of shrink fitting, since the fastening force cannot be confirmed, the interference must be set relatively large, and as a result, there is a problem that residual stress may become large depending on the case. In particular, as mentioned above, relief grooves 9b and 8c are formed in the movable blade body 9 and the holder 8 to avoid interference with the stopper head 13, so if the tightening allowance is made larger than necessary, cranking will occur. considered to be a thing.

Therefore, it is believed that by setting the tightening margin relatively small, the occurrence of the crank can be suppressed and the life can be extended. However, if the tightening margin is small, there is a concern that the movable blade body may rotate or come out of the holder due to repeated application of impact force.

In order to solve the above-mentioned problems such as rotation, both the above-mentioned members 8.9
It is conceivable to combine them by, for example, the so-called metal flow method described in Japanese Patent Application Laid-Open No. 55-94740.

In this method, as shown in FIG. 8 t8), a circumferential groove Sta is formed in the annular first metal member 51, and an axial groove 51b is formed at the bottom of the groove 51a. This first metal member 51 has a smaller deformation resistance than this,
The second metal member 52 having the coupling hole 52a is fitted and positioned at a predetermined position. In this state, the periphery of the coupling hole 52a of the second metal member 52 is pressurized with upper and lower molds 53 and 54 having annular projections 53a and 54a. As a result, as shown in FIG. As a result, both members 51 and 52 are connected.

By the way, the conventional metal flow method described above is a method in which a part of one metal member is plastically deformed and flows into the groove of the other metal member, so the deformation resistance of at least one metal member is relatively small (hardness low). However, since both the movable blade body and the holder of the cutting machine to which the present invention is directed are generally made of materials with considerably high hardness, it is difficult to employ the above-mentioned conventional metal flow method.

In addition, in the metal flow method described above, the ratio w/
The smaller d is, the larger the bonding force is, and conversely, the larger the ratio is, the smaller the bonding force is. In order to reduce the above ratio, it is necessary to make the pressure-type convex portions 53a and 54a elongated.

However, if it is made too thin, there is a risk that a crank will form near the base of the convex portion, and therefore there is a natural limit, and currently the limit is about W/d-1. Furthermore, if the width W is too narrow, the surface pressure of the convex portions 53a and 54a will become extremely high, and a cemented carbide or the like will be required for the mold, which will cause an increase in cost. Furthermore, in this case, there is also the problem that the pressure trace becomes deep.

The present invention has been made in response to the above-mentioned needs, and is a cutting machine that can prevent the occurrence of cranking, greatly extend the life of the movable blade, and that can reliably prevent the movable blade body from pulling out and rotating. The purpose of this invention is to provide a movable blade main body holding structure.

[Means for solving problems]

Therefore, the present invention provides a fixed blade, a movable blade having a movable blade body held by a holder, a positioning member inserted into the movable blade body so as to face the material to be cut, and defining the cutting length.
A cutting machine that moves the movable blade in a direction perpendicular to the material to be cut and is provided with an actuator that defines the movement of the movable blade to a predetermined stroke, and a structure for holding the movable blade main body with a holder. Then, the movable blade body is fitted and inserted into the holding hole formed in the holder at room temperature, an annular groove is formed at the boundary between the movable blade body and the holder, and the annular groove of the movable blade body and the holder is formed. A coupling groove extending in the circumferential direction and the axial direction is formed on the constituent surface, and a protrusion is formed near the edge of the groove, and the deformation resistance is lower than that of the movable blade main body and the holder within the annular groove. The present invention is characterized in that a joining metal member is inserted and pressurized, and as a result of the pressurization, the protrusion plastically deforms a part of the metal member, thereby causing a plastically deformed portion to flow into and fit into the groove.

In the present invention, the movable blade main body and the holder are fitted and inserted by so-called interference fitting or intermediate fitting.

Gap fit can be used.

Further, as a mechanism for moving the movable blade in the actuating device of the present invention, for example, a striking mechanism such as an air hammer, a crank AM, or the like can be employed.

[Effect]

To assemble the movable blade main body and the holder of the present invention, first, the movable blade main body is fitted and inserted into the holder at room temperature for temporary bonding, and a metal member for coupling is inserted into the annular groove of this temporary bonded body. Press with a pressure mold. Then, a portion of the coupling metal member is plastically deformed by the protrusion integrally formed on the edge of the coupling groove, and the plastically deformed portion flows into the coupling groove and fits into the portion.

The joining method of the present invention is characterized in that the joining metal member is plastically deformed by a protrusion (corresponding to a pressurized punch) that is integrally formed on the parts to be joined, such as the movable blade body and the holder. In order to distinguish it from the conventional metal flow method, this method is hereinafter referred to as the work punch type metal flow method.

In this way, in the present invention, the movable blade body and the holder are fitted together at room temperature, so residual stress does not become excessive as in the case of shrink fitting in the conventional example described above, and therefore it is possible to prevent the occurrence of cranking. .

On the other hand, if the fastening force between the movable blade body and the holder is simply reduced, there is a concern that the movable blade body may rotate or be removed from the holder.However, in the present invention, the movable blade body and the holder are Since the plastically deformed portions of the coupling metal members are flow-fitted into the respective coupling grooves and are mutually coupled, rotation and removal of the movable blade body can be reliably prevented.

In the present invention, a method is adopted in which a metal member is used for coupling, which has lower deformation resistance than the movable blade main body and the holder, and is separate from the two members, so that the two members, both of which have high hardness, can be coupled by the metal flow method.

Further, in the present invention, the coupling metal member is plastically deformed by a protrusion integrally formed on the movable blade main body and the holder.
Since we have adopted the work punch method, there is no rack problem that occurs when the convex part of the conventional pressure type is elongated. It is possible to do so without creating deep pressure marks.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 4 are diagrams for explaining a movable blade main body holding structure of an impact cutting machine according to an embodiment of the present invention.
The structure of this embodiment is basically the same structure as the conventional device described above except for the movable blade, so the movable blade will be explained below.

In the figure, 20 is a movable blade, which is the movable blade main body 2.
1 and a holder 22 for holding it.

The movable blade main body 21 is, for example, a disc-shaped one made of 5KH9 (hardness HRC60), and has a through hole 21a formed in its axis into which the workpiece W is inserted, and the fixed blade side end thereof is a cutting blade 21g. It becomes. Further, a relief groove 21c is formed in a 0-shape on the back side (the side opposite to the cutting edge) of the movable blade main body 21. Note that each corner of the movable blade main body 21 except for the cutting edge 21g is rounded with a radius of about 1 to 3n. This is to avoid stress concentration.

The holder 22 is, for example, 5KD61 (hardness HRC4).
A circular holding hole 22a is formed at the axis thereof, and an escape groove 22c is formed on the back side of the holding groove 22c, which extends upwardly from the above-mentioned escape groove 21c. Further, a convex portion 22b is formed on the upper edge of the holder 22 and is struck by a striking device. The movable blade main body 21 is
It is fitted and held in the holding hole 22a of the holder 22 by press-fitting (interference fitting) at room temperature. In addition, the movable blade body 21
and the holder 22 may be fitted with an intermediate fit or a gap area, and each corner of this holder 22 has one
A chamfering process with a radius of 1 to 3 fi is applied. This is to avoid stress concentration.

The movable blade main body 21 and the holder 22 are connected to each other at the rear side of the boundary by a work punch type metal flow method via a coupling ring 23 made of, for example, 345C. This coupling portion will be explained in detail below.

Movable blade body 21. Annular step portions 21h and 22h are formed in the coupling portion of the holder 22 to form an annular groove 24 into which the coupling ring 23 is inserted. , this annular groove 2
4 may be shifted toward the movable blade main body 21 side, or may be located in the center of both, and each of the above-mentioned stepped portions 21h,
A V-shaped circumferential groove 21d is provided on the annular groove forming surface 22h.

22d are formed in three rows each. Further, in the groove portion, an axial groove 21e is formed by low left machining.

226 are formed at predetermined pitches in a direction orthogonal to the circumferential grooves ld and 22d, and each of the stepped portions 21h
, 22h are integrally formed with protrusions 21f and 22f on the inner edges in the axial direction. The plastically deformed portions 23a of the coupling ring 23 fit into each of the grooves, thereby coupling the movable blade main body 21 and the holder 22.

Note that the shape of the grooves 21d and 22d is not limited to the V-shape, and the number of grooves is not limited to three rows.

When assembling the movable blade 20, first the movable blade main body 21. A holder 22 is prepared, and the movable blade main body 21 is press-fitted into the holding hole 22a at room temperature for temporary connection.

Next, the temporary combined body is placed on the lower mold 30 with the annular groove 24 side facing up, and the connecting ring 23 is fitted and inserted into the annular groove 24, and the lower end surface of this is placed. 2
3b at the beginning of the preamble 21f.

221. Then, the coupling ring 23 is further pressed by the protrusion 31a of the upper die 31 and lowered. Then, the outer peripheral edge and inner peripheral edge portions of the lower end surface 23b are plastically deformed because their downward movement is prevented by the projections 21f and 22f, and the plastically deformed portion 23a forms the circumferential groove 21d,
22d, and into the axial grooves 21e and 22e, thereby coupling the movable blade main body 21 and the holder 22.

Next, the effects of this embodiment will be explained.

In this embodiment, the movable blade body 21 is fitted and held in the holder 22 by press-fitting at room temperature, so that the force to compress the movable blade body 21 inward and the holder 22 The force required to push and spread the movable blade body 21 outward is small. Unreasonable residual stress does not occur in the holder 22, especially near the bottom of the clearance groove, and as a result, the movable blade body 21. The life of the movable blade 20 can be extended by preventing the holder 22 from being cranked.

Further, in this embodiment, the movable blade main body 21 and the holder 22 are connected via the coupling ring 23, so that the movable blade main body 21 can be prevented from coming off in the axial direction or rotating around the axis. That is, in this embodiment, the engagement between the plastically deformed portion 23a of the coupling ring 23 and the circumferential grooves 21d and 22d prevents the axially coming off, and the plastically deformed portion 23a and the axially grooves 21@, 22 (By engaging with I, rotation of the movable blade main body 21 can be reliably prevented.

Furthermore, since a method of using the coupling ring 23, which is a separate component with lower deformation resistance than the movable blade body and the holder, the movable blade body 21 and the holder 22, both of which have high hardness, can be coupled.

Moreover, in this case, the movable blade main body 21. Since we have adopted a work punch method in which the coupling ring 23 is plastically deformed using the protrusions 21f and 22f integrally formed on the holder 22, there are almost no restrictions on w/d as in the case of pressurizing with the protrusions of a pressure mold. , thus the bonding strength can be significantly increased. Furthermore, since the entire surface of the coupling ring 23 is pressurized by the upper mold 31, there is no need for deep pressure traces.

〔Effect of the invention〕

As described above, according to the movable blade main body holding structure of a cutting machine according to the present invention, the movable blade main body is fitted and inserted into the holding hole of the holder at room temperature, and the movable blade main body and the holder are joined together. Since the joint is made by fitting the plastically deformed part of the joining metal member into the concave groove, cracking of the movable blade body and holder can be prevented, extending the life of the movable blade, and the rotation of the movable blade body can be prevented.

This has the effect of reliably preventing removal.

[Brief explanation of the drawing]

1 to 4 are diagrams for explaining a movable blade main body holding structure of an impact cutting machine according to an embodiment of the present invention,
Figure 1 is a cross-sectional side view, Figure 2 is a back view, Figure 3 is a cross-sectional side view showing the assembly process of the movable blade, Figures 4 (a) and 4 (
bl is an enlarged sectional view of the joint, FIGS. 5 to 7 are views showing conventional examples, FIG. 5 is a sectional front view of the percussion cutting machine, FIG. 6 is a sectional side view of the movable blade, and FIG. Figure 7 is its rear view.
Figure 8 (a) 5 Figure 8 (bl is a sectional view showing the conventional metal flow method. In the figure, 1 is a percussion type cutting machine, 3 is a fixed blade, 3a is a guide hole, 7 is a percussion device ( (actuating device), 13 is a stopper head (positioning member), 20 is a movable blade, 21.28 is a movable blade body, 21a, 28a are through holes, 21d, 22d are circumferential grooves, 21e, 22e are axial grooves. , 21f, 22f are protrusions, 21h
, 22h is a stepped portion (annular groove forming surface), 22 is a holder, 22
a is a holding hole, 23 is a coupling ring (metal member for coupling), 2
3a is a plastically deformed portion, 24 is an annular groove, and W is a workpiece (material to be cut). Patent Applicant Yamaha Motor Co., Ltd. Agent Patent Attorney Tsutomu Shimofu Figure 2 Figure 3

Claims (1)

[Claims] (1) A holder holds a fixed blade having a guide hole into which the material to be cut is inserted, and a movable blade body having a through hole into which the tip end extending from the guide hole of the material to be cut is inserted; a movable blade disposed to be movable in a direction perpendicular to the material to be cut; a positioning member inserted into the movable blade body so as to face the tip of the material to be cut; and a positioning member for defining a cutting length; and the movable blade. A cutting machine equipped with an actuating device that moves the movable blade in a direction perpendicular to the material to be cut and defines the movement of the movable blade to a predetermined stroke, the structure for holding the movable blade main body with a holder, The movable blade body is fitted and inserted into the holding hole formed in the holder at room temperature, an annular groove is formed at the boundary between the movable blade body and the holder, and an annular groove forming surface of the movable blade body and the holder is formed. , a coupling groove extending in the circumferential direction and the axial direction is formed, a protrusion is formed near the edge of the groove, and a coupling metal having lower deformation resistance than the movable blade main body and the holder is placed in the annular groove. A cutting machine characterized in that a member is inserted and pressurized, and the protrusion plastically deforms a part of the coupling metal member by the pressurization, and a plastically deformed portion is flow-fitted into the groove. movable blade body holding structure.