JPH08117883A - Trimming method and device therefor - Google Patents

Abstract

PURPOSE: To surely cut and remove burr on the external circumferential face of a work and to prevent the front face of the work from causing a flaw at the time of ironing in the following process. CONSTITUTION: In a trimming method where a shaft like work W is set on a trimming die 26 and the burr R formed on the circumference of the work W is cut and removed while moving the work in the axial direction by pressing the work with a punch 16, each die piece 26p of the trimming die 26 divided into plural numbers in the circumferential direction is moved to the outside of the radial direction only by the equal dimension. Then, in a state where a prescribed clearance is generated between the work W and the trimming die 26, a process to set the work W on the trimming die 26, and after this process, a process to make the clearance between the trimming die 26 and the work W into almost zero by moving each die piece 26p of the trimming die 26 to the inside of radial direction and continuing each die piece 26p mutually are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention sets a shaft-shaped work inside a trimming die, presses the work with a punch, and moves the work in the axial direction while cutting out burrs formed around the work. Trimming method and apparatus therefor.

[0002]

2. Description of the Related Art A conventional trimming method and apparatus therefor will be described with reference to FIGS. The conventional trimming device 2 is a device that removes a brim-shaped burr R formed around a cylindrical work W and then irons the work W. And a punch 6 for pushing W. As shown in FIG. 8, the die 4 is provided with a cylindrical die case 4c. Inside the die case 4c, a trimming die 4t, a first ironing die 4x, and a second ironing die are sequentially arranged from the top. 4y and the third ironing die 4z are coaxially positioned and fixed by press fitting.

The trimming die 4t has a tubular shape, and its inner diameter is set to be slightly larger than the outer diameter of the work W. Therefore, the work W is the trimming die 4
When stored in t, the space between both W and 4t is as shown in FIG.
As shown in, a predetermined clearance α is secured. Further, a cutting edge 4s for cutting off the burr R of the work W is formed in a ring shape on the upper surface of the trimming die 4t. The first ironing die 4x, the second ironing die 4y, and the third ironing die 4z are also cylindrical in shape, and the outer peripheral surface of the work W is located at the axial center position of each die 4x, 4y, 4z. Lands (not shown) for squeezing are formed.

Work W using the trimming device 2
In order to perform the trimming process and the ironing process, first, the work W is stored inside the trimming die 4t.
As described above, since the inner diameter of the trimming die 4t is set to be slightly larger than the outer diameter of the work W, the work W is smoothly accommodated inside the trimming die 4t, and its tip (lower end) is the first ironing. It is held at a position where it comes into contact with the land of the die 4x. In this state, the work W and the trimming die 4t are positioned substantially coaxially with each other, and a predetermined clearance α is secured between the two W and 4t. Next, when the punch 6 descends and the work W is pushed into the die 4, as shown in FIG.
The tip portion of the workpiece W is ironed, and the brim-shaped burr R of the workpiece W contacts the cutting edge 4s of the trimming die 4t.
Further, when the punch 6 descends from this state and the work W is pushed into the mold 4, the ironing process is continuously performed at the tip of the work W, and as shown in FIG. R is cut off by the cutting blade 4s.
Then, the work W is continuously pushed into the die 4 by the punch 6, whereby the entire outer peripheral surface of the work W is ironed. When the ironing process is completed, the work W is discharged from the lower side of the die 4 to the outside.

[0005]

However, in the above-described trimming device 2, the work W is placed in the trimming die 4.
A predetermined clearance α is provided between both W and 4t in a state of being housed inside t. Then, with the clearance α provided, the work W is pushed down by the punch 6 and the burr R is cut off. Therefore, the portion where the burr R is cut off is shown in FIG.
As shown in, the step T due to the clearance α remains in a ring shape. Therefore, when performing the ironing process, there is a problem that the portion of the step T is embedded inside and a flaw is generated on the surface of the work W. In order to solve the above-mentioned problem, a method of making the inner diameter of the trimming die 4t substantially equal to the outer diameter of the work W and making the clearance α between both W and 4t zero can be considered. However, if the clearance α is set to zero, it becomes difficult to insert the work W into the trimming die 4t, and there is a problem that the surface of the work W is flawed by the cutting edge 4s of the trimming die 4t at the time of insertion. The technical problem of the present invention is to secure a predetermined clearance between the two when setting the work on the trimming die and to make the clearance between the two zero when cutting the burr from the work. Make sure to remove the burr from the work,
It is intended to improve the trimming performance.

[0006]

[Means, actions, and effects for solving the problems]

[Means according to Claim 1 for Solving the Problems] The above problems are solved by a trimming method having the following features. That is, the trimming method according to claim 1 sets a shaft-shaped work on a trimming die, presses the work with a punch and moves the work in the axial direction,
In the trimming method for cutting burrs formed around the work, the die pieces of each of the trimming dies that are divided into a plurality in the circumferential direction are moved radially outward by an equal dimension, and the work and the trimming die are separated. A step of setting the work on the trimming die in a state where a predetermined clearance is generated, and after the step,
Moving each die piece of the trimming die inward in the radial direction so that the die pieces are continuous with each other so that the clearance between the trimming die and the work is substantially zero. [Operation of the invention described in claim 1] According to the present invention,
When setting the work on the trimming die, each die piece is moved outward in the radial direction by the same dimension so that the clearance between them becomes a predetermined value. For this reason, the work can be set smoothly on the trimming die, and the outer peripheral surface of the work is not scratched. Further, when cutting burrs from the work, the respective die pieces are moved inward in the radial direction by the same size to positions which are continuous with each other, and the clearance between the work and the trimming die becomes almost zero. For this reason, it becomes possible to reliably cut off the burr from the base portion, and it is not necessary to leave a ring-shaped protrusion on the part where the burr is cut off as in the conventional case. [Effect of the invention described in claim 1] According to the present invention,
Since the burr on the outer peripheral surface of the work can be surely cut off, no flaw is generated on the surface of the work even when performing ironing in a subsequent step.

[Means according to Claim 2 for Solving the Problem] In this trimming device, a shaft-shaped work is set on a trimming die, and the work is pushed by a punch to move the work in the axial direction. In a trimming device for cutting burrs formed around the periphery of a trimming die, a trimming die divided into a plurality in the circumferential direction and a die piece moving mechanism for moving each die piece constituting the trimming die by an equal size in the radial direction. And have. [Operation of the invention described in claim 2] According to the present invention,
The trimming die is divided into a plurality of pieces in the circumferential direction, and each die piece forming the trimming die is moved by the die piece moving mechanism by an equal size in the radial direction. Therefore, by adjusting the position of each die piece by the die piece moving mechanism, the clearance between them is set to a predetermined value when setting the work on the trimming die, and when the burr is cut from the work, It becomes possible to make zero. Therefore, the invention of claim 1 can be implemented by the present invention. [Effect of the invention described in claim 2] According to the present invention,
The same effect as that of the invention of claim 1 can be obtained.

[Means for Solving the Problems] According to a third aspect of the present invention, in the trimming apparatus according to the second aspect, the die piece moving mechanism includes a tapered surface formed on each die piece. A ring-shaped taper surface formed on the inner wall of the tubular member and supporting each die piece in a state of being in surface contact with the tapered surface of the die piece, and the tapered surface of the die piece is a ring of the tubular member. A displacement member that relatively displaces each die piece in the axial direction of the tubular member by a predetermined distance while being in surface contact with the tapered surface. [Operation of the invention described in claim 3] According to the present invention,
Each die piece is supported by the tubular member with its tapered surface in surface contact with the ring-shaped tapered surface formed on the inner wall of the tubular member. Therefore, by displacing each die piece relative to the tubular member by a certain distance in the axial direction by the displacement member, each die piece is moved in the radial direction by a certain dimension by the action of the tapered surface. Therefore, when the work is set on the trimming die or when the burr is cut from the work, the clearance between the work and the trimming die can be adjusted by operating the displacement member. In this way, due to the structure in which the axial movement of each die piece is changed to the radial movement by the action of the tapered surface, the structure is simplified, and multiple die pieces can be moved in the radial direction by the same size at the same time. Will be able to. [Effect of the invention described in claim 3] According to the present invention,
Since the structure in which the movement of each die piece in the axial direction is changed to the movement in the radial direction by the action of the tapered surface, the structure is simple and highly reliable, and the equipment cost is not expensive.

[Means according to claim 4 for solving the problem] This trimming device is the trimming device according to claim 3, wherein the displacement member is slidable inside the tubular member. An ironing die for ironing a work that has been stored and passed through the trimming die, a connecting member that connects the ironing die and each die piece, and the ironing die is constant in the axial direction during the ironing process. It has a stopper that stops the movement of the ironing die when it is displaced by a distance. [Operation of the invention described in claim 4] According to the present invention,
The ironing die and each die piece are connected by a connecting member. Therefore, when the ironing die is integrated with the work due to the frictional force during the ironing and is pushed axially by the work, each die piece is also moved in the axial direction of the tubular member. That is, each die piece is moved in the axial direction of the tubular member by the ironing force. Therefore, a special drive source for moving the die piece in the axial direction, for example, a hydraulic cylinder or the like is unnecessary. Further, by positioning the stopper at an appropriate position, the axial displacement of the ironing die can be maintained at a constant value, and the radial displacement of each die piece can also be maintained at a constant value. . [Effect of the invention described in claim 4] According to the present invention,
A special driving source for moving the die pieces in order to move each die piece in the radial direction by the ironing force,
For example, a hydraulic cylinder or the like is not needed, and the equipment cost is reduced.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A trimming method and apparatus therefor according to an embodiment of the present invention will be described below with reference to FIGS.
Here, FIG. 1 is a vertical cross-sectional view of the trimming device according to the present embodiment, FIG. 2 is a detailed view of a II portion of FIG. 1, and FIG.
It is a III arrow view. 4 to 7 are a longitudinal sectional view, a plan view and the like showing a state in which trimming processing and ironing processing are being performed by the trimming device according to the present embodiment. The trimming device 10 according to the present embodiment is a device for cutting a collar-shaped burr R formed around a cylindrical work W and then ironing the work W, as shown in FIG. Further, it is composed of a die 20 and a punch 16 for pushing the work W into the die 20.

Further, the mold 20 is composed of a substantially cylindrical die case 22, a trimming die 26 and an ironing die 24 which are vertically accommodated in the die case 22, and the base 40 of the die 40 is provided. It is positioned at a predetermined position above. The trimming die 26 is a substantially inverted frustoconical mold for trimming, and has an opening 26h for allowing a cylindrical work W to pass therethrough.
Further, around the opening 26h, a cutting edge 26s for cutting out the burr R is provided in a ring shape. Further, as shown in FIG. 3, the trimming die 26 is divided into four in the circumferential direction, and the divided plane fan-shaped die pieces 26p are connected to each other via a spring 26x. ing. Here, the spring 26x is urged in a direction to separate the die pieces 26p from each other.

The trimming die 26 has a conical surface 26t (hereinafter referred to as a tapered surface 26t) formed on a lower side surface thereof, and a tapered surface 22t (hereinafter referred to as a tapered surface 26t) formed in a ring shape on an upper inner wall surface of the die case 22. It is housed in the upper part of the die case 22 in a state of being in surface contact with a ring-shaped tapered surface 22t). With this structure, by displacing each die piece 26p downward by a certain distance by a method described later, the action of both the tapered surfaces 26t and 22t causes the die pieces 26p to move in the spring 26.
Move radially inward until they touch each other against the spring force of x. As a result, the inner diameter of the opening 26h formed in the center of the trimming die 26 is reduced and becomes substantially equal to the outer diameter of the work W. On the contrary, by displacing each die piece 26p upward, the die pieces 26p are separated from each other by the spring force of the spring 26x, and the respective die surfaces 26t are acted by the two tapered surfaces 22t and 26t.
Moves radially outward. As a result, the inner diameter of the opening 26h formed at the center of the trimming die 26 increases, and becomes larger than the outer diameter of the work W by a predetermined dimension.

Bolt holes 26k are formed in each die piece 26p of the trimming die 26, and a bolt 28 for connecting the die piece 26p to the ironing die 24 is passed through the bolt holes 26k. It has become so. Here, since the diameter of the bolt hole 26k is set to be sufficiently larger than the outer diameter of the bolt 28,
The radial movement of the die piece 26p is not hindered by the bolt 28.

The die case 22 is formed with a small diameter hole 22s continuously below the ring-shaped tapered surface 22t, and a large diameter hole 22b is formed below the small diameter hole 22s via a step 22d. There is. And the die case 22
The ironing die 24 is housed in the positions of the small-diameter holes 22s and the large-diameter holes 22b so as to be slidable in the axial direction. That is, the die case 22 corresponds to the tubular member of the present invention. The ironing die 24 is a substantially cylindrical die for ironing the work W, and includes a case portion 25, a first ironing die 32, a second ironing die 34, and a second ironing die 34, which are positioned inside the case portion 25. It is composed of a third ironing die 36.

Further, the case portion 25 has a small-diameter connecting portion 25s formed on the upper portion thereof.
A large-diameter die storage portion 25b underneath s via a step 25d
Are formed. The connecting portion 25s of the case portion 25 is accommodated in the small diameter hole 22s of the die case 22, and the die accommodating portion 25b is accommodated in the large diameter hole 22b of the die case 22, and the step 25d is accommodated in the die case. 22
The case portion 25 can be raised in the die case 22 until it comes into contact with the step 22d. A groove 25z is formed in a ring shape on the lower end surface of the case portion 25, and the ring-shaped urethane spring 2 is formed in the groove 25z.
9 is stored. Thus, when the mold 20 is positioned on the base 40, the urethane spring 29 is sandwiched between the case portion 25 and the base 40 and compressed, and the case portion 25 has a spring force of the urethane spring 29. Is always pushed up to the upper limit position. When an external force greater than the spring force of the urethane spring 29 is applied downward to the case portion 25, the case portion 25 descends to a position where the lower end surface of the case portion 25 contacts the base 40. That is, the ironing die 24 can move up and down in the die case 22 from the step 22d to the base 40. Therefore,
The base 40 corresponds to the stopper of the present invention.

Further, the connecting portion 25s of the case portion 25
At the center, a work hole 25x for passing the work W is formed, and female screw holes 25w are formed at four positions around the work hole 25x. And the female screw hole 2
A bolt 28 for connecting the die piece 26p of the trimming die 26 to the connecting portion 25s is screwed into the 5w. As a result, the die piece 26p
It becomes possible to move up and down in the die case 22 in conjunction with the ironing die 24. Here, the distance that the ironing die 24 descends from the upper limit position to the position (lower limit position) in contact with the base 40 is such that each die piece 26p of the trimming die 26 can move to a position in which the die pieces 26p contact each other inward in the radial direction. Set to distance. Further, a die accommodating hole 25y is formed in the die accommodating portion 25b of the case portion 25 coaxially with the work hole 25x of the connecting portion 25s, and the first ironing die 32 is formed in the die accommodating hole 25y.
The second ironing die 34 and the third ironing die 36 are coaxially press-fitted and fixed in order from the top. The first ironing die 32, the second ironing die 34, and the third ironing die 36 have a tubular shape, and each die 32, 34, 36 has a cylindrical shape.
Lands 32r, 34r, 36r for squeezing the outer peripheral surface of the work W are formed at the central position in the axial direction of. Here, the center line of each of the dies 32, 34, 36 is made to coincide with the center line of the work discharge port 42 of the base 40 when the mold 20 is positioned at a predetermined position on the base 40. Has become.

Next, the trimming device 10 according to the present embodiment.
A method of trimming and ironing the work W will be described using. Here, before the work W is set in the mold 20, the ironing die 24 is moved up to the upper limit position by the spring force of the urethane spring 29, that is, the step 25d contacts the step 22d of the die case 22. . Therefore, the trimming die 26 located on the ironing die 24 is also pushed up to the upper limit position, and the die pieces 26p are separated from each other by the spring force of the spring 26x as shown in FIG. The hole 26h is held in a state of being larger than the outer diameter of the work W by a predetermined dimension. Then, in this state, as shown in FIG. 1, the work W is set in the mold 20. At this time,
As described above, since the opening 26h of the trimming die 26 is larger than the outer diameter of the work W, the work W is smoothly passed through the opening 26h of the trimming die 26, and its tip (lower end) is the first ironing. The die 32 is held at a position in contact with the land 32r. As a result, the work W and the trimming die 26 are positioned substantially coaxially with each other, and as shown in FIG. 2, a predetermined clearance β is secured between the two W and 26.

Next, the punch 16 descends to move the work W.
When is pushed into the mold 20, the ironing die 24 is integrated with the work W by the frictional force during the ironing process, and moves downward together with the work W against the spring force of the urethane spring 29.
Then, as shown in FIG. 4, with the lower end surface of the ironing die 24 in contact with the base 40, the ironing die 24
Is stopped and the work W is continuously lowered and is pushed into the ironing die 24 to perform ironing. In this way, the ironing die 24 is lowered by a certain distance from the upper limit position to the lower limit position, so that each die piece 26p connected to the ironing die 24 by the bolt 28 is lowered by a certain distance, and the tapered surface 26t, Two
Due to the action of 2t, each die piece 26p causes the spring 26
Move radially inward to a position where they touch each other against the spring force of x. As a result, the inner diameter of the opening 26h formed in the trimming die 26 decreases and becomes almost equal to the outer diameter of the work W, and as shown in FIGS. 5 and 6, between the work W and the trimming die 26, The clearance is almost zero.

From this state, when the punch 16 is further lowered and the work W is pushed into the die 20, the work W is continuously ironed, and the work W is also continued.
The collar-shaped burr R comes into contact with the cutting edge 26s of the trimming die 26, and as shown in FIG. 7, the burr R is reliably cut off from the base portion. For this reason, the protrusion does not remain in a ring shape at the portion where the burr is cut. Then, the work W is continuously moved to the mold 2 by the punch 16.
By pushing into 0, the entire outer peripheral surface of the work W is ironed. As described above, since the burr R of the work W is reliably cut off from the base portion, the rest of the burr R is not embedded in the work W during the ironing process, and a flaw is not generated on the surface of the work W. Absent. In this way, when the ironing process is completed, the work W is discharged from the lower side of the die 20 to the work discharge port 42 of the base 40.
Then, when the discharge of the work W is completed, the punch 16 moves up. As a result, as described above, the ironing die 24
The trimming die 26 is pushed up to the upper limit position by the spring force of the urethane spring 29, the die pieces 26p of the trimming die 26 are separated from each other by the spring force of the spring 26x, and the opening 26h is larger than the outer diameter of the work W. The inner diameter is kept to be increased by a predetermined size.

As described above, according to this embodiment, the work W
Is set on the trimming die 26, each die piece 26p is moved radially outward by an equal dimension so that the clearance between them becomes a predetermined value β. For this reason,
The work W can be set smoothly on the trimming die 26, and the outer peripheral surface of the work W is not scratched. On the other hand, when cutting the burr R from the work W, the die pieces 26p are moved inward in the radial direction by the same size, and the clearance between the work W and the trimming die 26 becomes almost zero. Therefore, the burr R can be surely cut off from the base portion, and a ring-shaped protrusion is not left at the part where the burr R is cut off unlike in the conventional case. Therefore, even when performing ironing or the like, no flaw is generated on the surface of the work.

Further, the vertical movement of the ironing die 24 is caused by the action of the taper surfaces 26t and 22t.
Since the structure is changed to the radial movement of 6p, the structure is simple and the plurality of die pieces 26p can be easily moved in the radial direction by the same size at the same time. Furthermore, since a special drive source for moving the die piece 26p, such as a hydraulic cylinder, is not required,
Equipment cost is reduced. In addition, in this embodiment, the die piece 2 is used by utilizing the vertical movement of the ironing die 24.
The method of moving the 6p is adopted, but the method is not limited to this.
It is also possible to move 6p up and down. Alternatively, a method of directly moving the plurality of die pieces 26p in the radial direction by rails or the like without using the tapered surfaces 26t and 22t is also possible.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a trimming device according to an embodiment of the present invention.

FIG. 2 is a detailed view of section II in FIG.

3 is a view taken along the line III-III in FIG.

FIG. 4 is a vertical cross-sectional view showing a state in which trimming processing and ironing processing are being performed by the trimming device according to the embodiment of the present invention.

FIG. 5 is a detailed view of a V portion of FIG.

6 is a VI-VI arrow view of FIG. 4.

FIG. 7 is a detailed cross-sectional view showing a state in which trimming processing is being performed by the trimming device according to the embodiment of the present invention.

FIG. 8 is a vertical cross-sectional view of a conventional trimming device.

FIG. 9 is a vertical cross-sectional view showing a state in which a trimming process and an ironing process are performed by a conventional trimming device.

FIG. 10 is a vertical cross-sectional view showing a state in which trimming processing and ironing processing are performed by a conventional trimming device.

[Explanation of symbols]

 W work R burr 16 punch 22 die case (cylindrical member) 22t ring-shaped taper surface (die piece moving mechanism) 22d step (stopper) 24 ironing die (die piece moving mechanism) 26 trimming die 26p die piece 26t taper surface (die) One-way moving mechanism) 28 bolts (connecting member) 40 base (stopper)

Claims (4)

[Claims] 1. A trimming method in which a shaft-shaped work is set on a trimming die, and while the work is pressed by a punch to move in the axial direction, a burr formed around the work is removed, in a circumferential direction. The work pieces are set on the trimming dies in a state where a predetermined clearance is generated between the work and the trimming die by moving the die pieces of the plurality of trimming dies radially outward by the same size. And the step of moving each die piece of the trimming die inward in the radial direction so that the die pieces are continuous with each other and the clearance between the trimming die and the work is substantially zero. And a trimming method comprising: 2. A trimming device for setting a shaft-shaped work on a trimming die, pressing the work with a punch and moving the work in the axial direction, and removing burrs formed around the work, in a circumferential direction. A trimming device comprising: a trimming die divided into a plurality of pieces; and a die piece moving mechanism for moving each die piece forming the trimming die by an equal size in a radial direction. 3. The trimming device according to claim 2, wherein the die piece moving mechanism includes a taper surface formed on each die piece and an inner wall of a tubular member, and a taper of the die piece. A ring-shaped taper surface supporting each die piece in a surface contact with the surface, and a state in which the taper surface of the die piece is in surface contact with the ring-shaped taper surface of the tubular member, A trimming device comprising: a displacement member that relatively displaces a certain distance in the axial direction of the tubular member. 4. The trimming device according to claim 3, wherein the displacement member is accommodated in the tubular member in a slidable state, and irons a workpiece that has passed through the trimming die. An ironing die, a connecting member that connects the ironing die and each die piece, and a stopper that stops the movement of the ironing die when the ironing die is displaced by a certain distance in the axial direction during the ironing process. A trimming device characterized by being.