JP2008100282A - Method of drilling through-hole in workpiece peripheral wall and drilling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of drilling a through-hole in a workpiece peripheral wall and a drilling device which can prevent burrs from occurring on the inner peripheral surface of a tubular unit, are high in productivity, and can significantly reduce processing cost. <P>SOLUTION: The drilling device comprises one 20 of dies for processing a workpiece 10, a feeder means 81 for sucking the workpiece 10 and feeding it to the die 20 while holding it so as to be able to slide in a punching direction, a punch 30 protruding shorter than the thickness of the peripheral wall from a rod-like cored bar 32 held in a cantilever form so as to be inserted into the inside of a tubular unit, and a pressurizing means 50 for relatively pressure-moving the punch 30 via the cored bar 32 in a direction of approaching the die 20 to thereby drive the punch 30 into the peripheral wall from the inside of the tubular unit, cause shearing and breaking, and drill a through-hole 70. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for drilling a through hole in a work peripheral wall in which a through hole is formed by press punching in a peripheral wall of the cylindrical part of a work having at least a part of the tubular part, a drilling device therefor, and a drilling device therefor The present invention relates to a work in which a through hole is opened by an installation method or a drilling device.

In order to open a through-hole in a workpiece, there are cutting with a drill, punching of a press, electric discharge machining, and the like. In the case where the workpiece has a cylindrical part such as a pipe in at least a part thereof, the above processing means can also be used to open a through hole in the peripheral wall of the cylindrical part.
However, in drilling with a drill or a press, burrs are generated at the hole edge, which takes time for deburring. In particular, when a through-hole is opened in the peripheral wall of the cylindrical portion, burrs are generated on the inner peripheral surface of the cylindrical portion when a drill is used or when punching is performed with a punch from the outside of the cylindrical portion. When the work is a small part, it is difficult to remove burrs generated inside the cylindrical portion in this way. Some workpieces do not allow burrs inside the cylindrical portion at all.
For this reason, conventionally, when the workpiece is a small part having a cylindrical part and the peripheral wall is relatively thick, electric discharge machining has been employed to open a through hole in the peripheral wall.
However, electric discharge machining takes a long machining time, the productivity is poor, and the machining cost cannot be reduced.

By the way, as shown in FIG. 33, for the plate material, a method of opening a through hole without causing burrs by punching the plate material (107b) has been proposed (see Patent Document 1).
In this process, a circumferential groove 174a corresponding to the diameter of the through hole 170a to be punched is formed on at least the back surface of the plate (work) (107b) by primary processing by pressing or cutting (FIG. 33 (a)), and FIG. As shown in (2), the punching punch (151a) is driven into the position corresponding to the center of the circumferential groove from the opposite side surface of the plate (107b) by secondary processing by pressing to open the through hole (170a). Note that reference numeral 178a denotes scrap (removed waste).
However, the method of opening a through-hole in this plate material is simply applied by pressing the punch 151a against the die 151b from directly above, and is not applicable when the through-hole is formed in the peripheral wall of the cylindrical part of the small part. .
Therefore, in order to prevent the occurrence of burrs on the inner side of the work, it is conceivable to punch with a press die (punch) from the inside of the cylindrical portion. However, in this case, a small mold that can be inserted into the inside of the cylindrical portion is required, and there has been no drilling method and apparatus having a sufficient life and high productivity of the mold.
Japanese Patent Laid-Open No. 5-42330 ([0005], [0006], [0009], [0019], etc.)

A problem to be solved regarding the method and apparatus for drilling a through hole in the work peripheral wall is that productivity is low in the conventional method and apparatus in order to open a through hole without a burr.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method and apparatus for drilling a through hole in a work peripheral wall that prevents burrs from occurring at least on the inner peripheral surface of the cylindrical portion, has high productivity, and can significantly reduce processing costs. Is to provide.

The present invention has the following configuration in order to achieve the above object.
According to one aspect of the method for drilling a through hole in a work peripheral wall according to the present invention, a method of drilling a through hole by press punching in the peripheral wall of the cylindrical part of a work having at least a part of the cylindrical part. The workpiece is attracted by the feeder means and held on the die while being slidably held in the punching direction, and is protruded shorter than the thickness of the peripheral wall on the rod-shaped cored bar held in a cantilever manner. The punch is inserted into the cylindrical part, and the punch is moved from the inside of the cylindrical part to the peripheral wall by relatively pressing and moving the punch through the core bar in a direction close to the die. A through hole is formed by driving, shearing and breaking, and when the through hole is drilled, the through hole is opened by sucking and removing from the discharge hole of the die waste. It is characterized by.

Further, according to one aspect of the method for drilling a through hole in the work peripheral wall according to the present invention, before the through hole is drilled, the outer side of the tubular portion corresponding to the planned drilling position of the through hole is formed. When the punch is punched into the peripheral wall to form a recess that is a peripheral edge that is slightly larger than the through-hole, and when the through-hole is drilled, the punch is moved from the inside of the tubular portion to the peripheral wall. It can be characterized in that it is driven to cause shearing and breaking to reach the periphery of the recess.
Further, according to one embodiment of the method for drilling a through hole in the work peripheral wall according to the present invention, when the punch and the die are relatively moved by pressure, the pressure is applied with a spring force interposed therebetween. It can be.

According to one aspect of the device for drilling a through hole in a work peripheral wall according to the present invention, the device for drilling a through hole by press punching in the peripheral wall of the tubular portion of the work having at least a part of the tubular portion. A die that is one of the molds for processing the workpiece, a feeder means that sucks the workpiece and supplies it to the die while slidably holding it in a punching direction, and a rod-shaped core held in a cantilever manner By projecting to the gold shorter than the thickness of the peripheral wall, the punch inserted into the inside of the cylindrical part, and by relatively pressing and moving the punch through the cored bar in the direction close to the die, A pressurizing means is provided for punching a punch into the peripheral wall from the inside of the cylindrical portion and causing a shear and breakage to form a through hole.
Further, according to one embodiment of the device for drilling a through hole in the work peripheral wall according to the present invention, the metal core is pressed in the inside of the cylindrical portion because the tip side where the punch is protruded is pressed. It is characterized in that it is formed narrower in the moving direction than the portion on the rear end side, and R is taken at the step portion between the front end side and the rear end side of the cored bar. .

  Moreover, according to one form of the through-hole drilling device in the workpiece peripheral wall according to the present invention, the through-hole is drilled by press punching in the peripheral wall of the cylindrical portion of the workpiece having at least a part of the cylindrical portion. A die that is one of the molds for processing the workpiece, feeder means that sucks the workpiece and holds it slidably in the punching direction, and feeds it to the die; A punch that is shorter than the thickness of the peripheral wall and is inserted into the cylindrical portion, and the punch is moved under pressure in a direction close to the die via the core. And a pressurizing means for punching the punch into the peripheral wall of the workpiece from the inside of the cylindrical portion and generating a through hole by causing shearing and breaking, and the end surface of the punch has an inner periphery of the cylindrical portion Chamfered along the shape of the surface It may be characterized in that.

Further, according to one embodiment of the device for drilling a through hole in the work peripheral wall according to the present invention, when the through hole is drilled, the punched hole is opened so as to open the through hole. It is possible to provide a suction means for sucking and removing from.
Moreover, according to one form of the through-hole drilling device in the workpiece peripheral wall according to the present invention, the suction means generates a negative pressure by the venturi effect by opening the compressed air to the flow path having a larger cross-sectional area. It can be characterized by being a negative pressure suction device.
Further, according to one embodiment of the drilling device for the through hole in the work peripheral wall according to the present invention, the elastic means is used to pressurize the punch and the die with a spring force when the punch and the die are relatively pressed and moved. It can be characterized by comprising.

  Further, according to the workpiece according to the present invention, the workpiece has a cylindrical portion at least in part, and the through-hole is opened in the peripheral wall of the cylindrical portion by the through-hole drilling device in the workpiece peripheral wall. Can be characterized.

According to one aspect of the method for drilling a through hole in a work peripheral wall according to the present invention, a through hole is formed by press punching in the peripheral wall of the tubular part of the work having at least a part of the tubular part. A method in which a concave portion to be a part of the through hole is formed on the outer peripheral portion of the peripheral wall by a means other than a press corresponding to a planned drilling position of the through hole. And a punch formed on a rod-shaped core bar held in a cantilever manner and having a slightly smaller peripheral edge than the recess is inserted into the cylindrical part, and the core bar The punch is driven and moved in the direction close to the die through the punch, so that the punch is driven into the peripheral wall from the inside of the cylindrical portion, and the shear and breakage reaching the peripheral edge of the recessed portion are caused to penetrate. A hole is formed.
Moreover, according to one form of the through-hole drilling method in the workpiece | work surrounding wall concerning this invention, means other than the press which forms the said recessed part in the outer peripheral part of the said surrounding wall are cutting, shaping | molding, or electrical discharge machining. Can be characterized.

  According to one aspect of the method for drilling a through hole in a work peripheral wall according to the present invention, a through hole is formed by press punching in the peripheral wall of the tubular part of the work having at least a part of the tubular part. In the method, the workpiece is positioned on the die, and a punch projecting shorter than the thickness of the peripheral wall is inserted into the rod-shaped core metal held in a cantilever state, and is inserted into the cylindrical portion. The process of punching the punch into the peripheral wall from the inside of the cylindrical portion and punching the through hole by dividing the punch in a direction close to the die through the cored bar is divided into two stages. In the first stage, the first punch is driven into the peripheral wall to cause shearing, so that a concave portion is formed on the inner wall surface and a convex portion is formed on the outer wall surface, In the second stage, the first Characterized by drilling the resulting let through hole finally broken by implanting second punch which is smaller in diameter into said recess while being longer projecting than inch.

Moreover, according to one form of the through-hole drilling method in the workpiece peripheral wall according to the present invention, the third step following the two-step step of drilling the through-hole is projected longer than the second punch. A third punch, which is provided and has a small diameter, is driven into the through hole from the inside of the tubular portion, and the through hole is opened by removing the punched debris.
Moreover, according to one form of the through-hole drilling method in the workpiece | work surrounding wall concerning this invention, the process of each said step can be performed using the same die | dye.

  Moreover, according to one form of the through-hole drilling device in the workpiece peripheral wall according to the present invention, the through-hole is drilled by press punching in the peripheral wall of the cylindrical portion of the workpiece having at least a part of the cylindrical portion. An apparatus, a die that is one of the molds for processing the workpiece, and a rod-shaped cored bar that is held in a cantilever manner so as to protrude shorter than the thickness of the peripheral wall, and the cylindrical part interposed through the cored bar The inner wall surface is recessed by being driven into the peripheral wall from the inside of the cylindrical portion by being relatively pressurized and moved in the direction close to the die. And a first punch for half-cutting so that a convex portion is formed on the outer wall surface, and a rod-shaped metal core held in a cantilever manner, which is shorter than the thickness of the peripheral wall and more than the first punch. Is long and has a small diameter. Then, it is inserted into the inside of the cylindrical part and is relatively pressed and moved in a direction close to the die, so that it is driven into the concave part from the inside of the cylindrical part, and finally breaks. Thus, a second punch for forming a through hole is provided.

Further, according to one form of the through-hole drilling device in the work peripheral wall according to the present invention, the rod-shaped cored bar held in a cantilever manner protrudes longer than the second punch and has a small diameter. The second punch is provided from the inner side of the cylindrical part by being inserted into the cylindrical part via the core and moved relatively in a direction close to the die. A third punch that is driven into the through-hole and opens the through-hole by removing the punched debris can be provided.
Moreover, according to one form of the through-hole drilling device in the workpiece peripheral wall according to the present invention, since the first punch and the second punch are constituent elements, at least two punches are provided. The number of the dies is one.

Moreover, according to one form of the through-hole drilling device in the work peripheral wall according to the present invention, each punch holder for holding each core metal in a state of projecting the end portion side provided with each punch, Each of the punch holders is detachably held, and is provided with one slide block that is slidable back and forth in the press punching direction, and by pressing the slide block, the punch holder and the core bar are used to press the punch. And a single pressurizing device for moving in the press punching direction.
Further, according to one aspect of the device for drilling a through hole in the work peripheral wall according to the present invention, the frame for guiding the punch holders so as to be held in parallel and movable in the attaching / detaching direction with respect to the slide block. A punch holder feeding mechanism which is provided with a body part and sequentially feeds to a predetermined position for attaching to and detaching from the slide block, and a punch holder sent to the predetermined position is reciprocated with respect to the slide block to be attached and detached. And a punch holder attaching / detaching mechanism.

  According to the through-hole drilling method and drilling device in the workpiece peripheral wall according to the present invention, at least the inner peripheral surface of the cylindrical portion is prevented from generating burrs, the productivity is high, and the machining cost is greatly reduced. it can.

Hereinafter, an example of the best mode concerning the drilling method and drilling device of the through hole in the work peripheral wall according to the present invention will be described in detail with reference to the accompanying drawings (FIGS. 1 to 9). FIG. 1 is a sectional view showing a drilling apparatus according to the present invention. 2 to 4 are sectional views for explaining the drilling process. FIG. 5 is a front view (a) and a bottom view (b) showing the shape of the punch. FIG. 6 is a cross-sectional view showing one embodiment of the negative pressure suction device. 7-9 is explanatory drawing which shows an apparatus system provided with the structure shown in FIGS.
The drilling device of this embodiment is a device that drills a through hole in the peripheral wall of the cylindrical portion of the workpiece by press punching.
Reference numeral 10 denotes a workpiece, which is an example having a cylindrical portion 12 at least in part. The work 10 is a cap of a hydraulic valve lifter and is a metal part formed by forging. For example, a small part having an inner diameter of about 6.5 mm and a peripheral wall thickness of about 2 mm. In the drilling device of this embodiment, a circular through hole 70 having a diameter of about 2 mm is drilled in the workpiece 10.

Reference numeral 20 denotes a die, which is one die for machining the workpiece 10. The die 20 is provided as a mold for opening a through hole 70 in the work 10 at the center of the receiving portion on which the work 10 is placed and positioned on the upper surface of the block member (die block 22).
Reference numeral 24 denotes a discharge hole for the punched residue, which has a shape that expands downward in a tapered shape. As a result, the punched residue 80 is suitably discharged without being caught on the way.

Reference numeral 30 denotes a punch, which protrudes from a rod-shaped cored bar 32 held in a cantilever manner shorter than the thickness of the peripheral wall 15 of the workpiece 10. In this embodiment, the peripheral wall 15 is provided in a state of projecting right below to a height of about half the thickness of the peripheral wall 15. Thus, since the core 30 can be formed thicker because the punch 30 is shorter, the life of the mold can be extended. That is, the escape stroke of the punch 30 is short, and the core metal 32 inserted into the work 10 can be thickened accordingly. Therefore, the strength can be increased and the life can be extended. Further, the punch 30 itself is shortened and is not easily damaged. Thereby, productivity can be improved and processing costs can be significantly reduced.
The rear part of the punch 30 is inserted into a fixing hole 35 (FIG. 2) provided on the distal end side 32a (FIG. 2) of the cored bar 32 and is positioned by a step 35b in the hole. As a result, the punch 30 is fixed in a state protruding from the lower surface 36 (FIG. 5) of the core metal 32 by a predetermined length.
Further, the fixing hole 35 has a lower side portion to which the punch 30 is fixed, and an upper side portion 35a on the opposite side is a small-diameter through hole. The punch 30 can be pierced and removed using the hole of the upper portion 35a. Thereby, replacement | exchange of the punch 30 can be performed easily.
It is also possible to integrally form the cored bar and the punch.
Moreover, this punch 30 will be in the state inserted in the inside of the cylindrical part 12 as shown in FIGS. Note that the punch 30 is relatively inserted into the cylindrical portion 12 also by transporting the workpiece 10 with a feeder and fitting the tip of the core 32 on which the punch 30 is projected.

The metal core 32 has a rear end side 32b (FIG. 2) opposite to the front end side 32a (FIG. 2) from which the punch 30 protrudes, and a holding hole of a block (elevating block 40) that holds the metal core 32. It is inserted in 42 in the horizontal direction and is detachably fixed. A flat portion 32c for preventing rotation is provided on the side surface of the cored bar 32 (FIG. 5A). For this reason, it can exchange easily and suitably.
The fixed state of the metal core 32 is a cantilever in which the distal end side 32a protrudes in the horizontal direction, and the metal core 32 is formed in a rod shape as described above. For this reason, when a press punching process is performed, a large moment is applied to the cored bar 32 due to pressure during pressing. Therefore, the core metal 32 is moved upward in this embodiment by the pressing pressure in the range of elastic deformation.
The “bending” is released at once when the through hole 70 is formed. That is, when the punch 30 breaks the peripheral wall 15 and pierces the through hole 70, the stress acting on the core metal 32 is released. Then, the cored bar 32 tries to flexibly shock to the opposite side (downward in this embodiment) with the force of releasing the stress. As a result, the punch 30 pushes the punched residue 80 in an impact direction. This effect appears more suitably because the rod-shaped cored bar 32 is fixed to the holding hole 42.
According to this, even if the punch 30 is protruded shorter than the thickness of the workpiece 10, the punch 30 is pushed so as to fly off, and the through hole 70 can be suitably opened. it can. As described above, since the punch 30 is short, the life of the mold can be extended, and the processing cost can be reduced.

Further, the metal core 32 is arranged so that the front end side 32a (FIG. 2) from which the punch 30 is projected can be moved in the pressurizing direction (vertical direction in this embodiment) inside the cylindrical portion 12 for press punching. It is formed narrower in the movement direction than the end side 32b (FIG. 2). As shown in each drawing, the upper surface portion of the distal end side 32a is cut to form a cut portion 34 (FIG. 5A). The cut height of the cut portion 34 is a distance that allows the vertical movement of the cored bar 32. Note that the upper surface of the cut portion 34 is cut in a circular arc shape along the inner peripheral surface of the tubular portion 12. The cross section of the cored bar 32 is formed in this way because it can be inserted into a limited space of the cylindrical portion 12 and can move a predetermined stroke during pressing, and can increase the strength. This is to obtain a cross-sectional area.
And R is taken by the step part 33 of the front end side 32a and the rear end side 32b of the metal core 32. As shown in FIG. As shown in FIGS. 1 to 4, in this embodiment, the stepped portion 33 is on the upper side of the cored bar 32, and the pressure is distributed so that stress concentration does not occur due to the R shape.
Further, the rear end side 32b of the cored bar 32 is fixed in a slightly inserted state so that the corner 33a at the upper end of the stepped portion 33 fits in the holding hole 42 of the elevating block 40. According to this, the pressure applied to the core metal 32 can be suitably received by the lifting block 40.
With such a configuration, the core metal 32 can be suitably prevented from being fatigued and the life of the mold can be extended. This also improves productivity and reduces processing costs.
Further, the R shape of the stepped portion 33 and the fixing position of the cored bar 32 also have a structure that preferably receives the “bending” of the above-described cored bar 32, and also works suitably for discharging the punched residue 80. .
The cored bar 32 only needs to have a shape in which at least the tip side 32a is a rod and can enter the inside of the workpiece 10. Therefore, the shape of the rear end side 32b is not particularly limited. However, in the case of this embodiment, there are advantages such as easy manufacture and replacement.

Reference numeral 50 denotes a pressurizing means, which moves the punch 30 relative to the die 20 in a direction close to the die 20 via the core metal 32 (moves downward in the present embodiment), so that the punch 30 is moved to the cylindrical portion 12. A through-hole 70 is formed by driving into the peripheral wall 15 of the workpiece from the inside to cause shear 18 (FIG. 3) and fracture 19 (FIG. 3).
In this embodiment, the punch 30 is lowered through the cored bar 32 held by the elevating block 40. Further, the punch 30 is driven downward in a direction perpendicular to the peripheral wall 15. Needless to say, the punching direction for forming the through hole 70 is not limited to the vertical direction as in this embodiment. For example, the workpiece 10 may be set in a progressive die or the like with the workpiece 10 standing, and the punch 30 may be driven in the horizontal direction to form the through hole 70.
52 is a pressurizing device, for example, a cylinder device may be used.
An elastic means 54 is disposed between the lifting block 40 and the pressurizing device 52 so that the punch 30 and the die 20 can be pressurized and moved with a springy force interposed therebetween. Has been. For example, a coil spring may be used as the elastic means 54.
Reference numeral 56 denotes a return spring, which is housed in a storage chamber 45 whose upper side opens below the lifting block 40 and is arranged and mounted between a base board (not shown). For example, a coil spring may be used as the return spring 56. After the pressurizing step is finished by the return spring 56, the punch 30 can be raised and returned to the position before pressurization via the lifting block 40 and the cored bar 32.
In order to make the break 19 properly after the shearing 18, the clearance between the die 20 and the punch 30 needs to be appropriate. An appropriate value for this appropriate clearance is empirically known. For example, when opening a circular through-hole in an iron-based material, the inner diameter of the die and the outer diameter of the punch may be set so as to satisfy the following relationship.
Die inner diameter = punch outer diameter + {work material thickness x (5-10%)} x 2

In the pressurizing means of this embodiment, since the elastic means 54 is interposed, pressure is gradually applied when the punch 30 hits the inner peripheral surface of the cylindrical portion 12. Since it is possible to prevent the pressure from acting on the impact, it is possible to reduce damage to the die such as the punch 30 missing.
Further, when the through hole 70 is formed by punching, the elastic force accumulated in the elastic means 54 is released at once. That is, when the punch 30 breaks the peripheral wall 15 and pierces the through hole 70, the compressed elastic means 54 such as a coil spring tends to return rapidly. Then, the punch 30 tends to move downward rapidly through the lifting block 40 and the cored bar 32 by the elastic force. Due to this action, the punch 30 impactively pushes the punched residue 80 in the discharge direction. For this reason, similarly to the above-described “bending” operation of the core metal 32, the punched residue 80 can be suitably discharged even when the punch 30 is short.
This also extends the life of the mold and reduces the processing cost.

Moreover, as shown in FIG.5 and FIG.23 (description of the right half), the end surface used as the cutting blade of the punch 30 of this form is chamfered so that the shape of the internal peripheral surface of the cylindrical part 12 of the workpiece | work 10 may be followed. Has been.
In this embodiment, the left and right portions of the punch 30 are chamfered corresponding to the circumferential surface on the inner side of the cylindrical portion 12 to form two chamfered portions 30a. That is, as is apparent from the description of the right half of FIG. 23, chamfered portions 30 a that are inclined with respect to a flat end surface 30 f perpendicular to the driving direction of the punch 30 are formed on both sides of the punch 30. Thereby, the angle of each corner | angular part in the end surface of the punch 30 in which this chamfered part 30a was formed becomes an obtuse angle larger than 90 degrees. The flat end surface 30f and the inclined surface of the chamfered portion 30a are parallel to the axis of the cored bar 32.
By forming the chamfered portion 30a in this way, the end surface of the punch 30 can be dispersedly brought into contact with the inner peripheral surface of the cylindrical portion 12, and the punch 30 can be prevented from being damaged. Similar to the cutting of the scissors, the shear angle is generated by the presence of the chamfered portion 30 a of the punch 30, and this can disperse the pressure during pressing, and the through hole 70 can be suitably opened. And since the said corner | angular part is an obtuse angle, the blade chip | tip of the punch 30 does not arise easily.
Further, as apparent from the description on the right half of FIG. 23, the tip side 32a of the cored bar 32 provided with the punch 30 is thickened corresponding to the height H3 of the chamfered portion 30a formed and shaved. Even so, it can be inserted inside the workpiece 10. The rigidity and durability of the cored bar 32 can be increased as the cross-sectional area of the distal end side 32a of the cored bar 32 becomes wider. Note that the description on the left half of FIG. 23 is a cross-sectional view illustrating a case where the chamfered portion 30a is not formed for comparison.
This also extends the life of the mold and reduces the processing cost.
Further, according to the punch 30 having the chamfered portion 30 a on the end surface, it is possible to prevent the punched residue 80 from sticking and sticking to the end surface of the punch 30. Thereby, productivity can be improved.

Reference numeral 60 denotes a suction means, and when the through hole 70 is drilled, the punched waste 80 is sucked and removed from the punched waste discharge hole 24 of the die 20 so as to open the through hole 70.
According to this, since the suction residue is generated when the extraction residue 80 is generated and suction removal is performed at the moment when the extraction residue 80 is generated, the extraction residue 80 can be suitably opened without remaining in the through hole 70.
Due to the action of the “bend” of the cored bar 32 and the action of the elastic means 54, the suction means 60 which is separated and shockedly pushed out when the through hole 70 is drilled is further applied to the suction means 60. Takes over and pulls. As a result, the cut residue 80 is suitably separated without being caught in the through hole 70 and is discharged to the outside through the discharge hole 24.
As the suction means 60, as shown in FIG. 6, a negative pressure suction device that generates a negative pressure by the venturi effect by opening the compressed air from the compressed air source 62 to the flow path 64 having a larger cross-sectional area is suitable. Can be used. In a normal state, a negative pressure state is maintained, and suction can be suitably performed when the drawn residue 80 is generated. Note that the extracted residue 80 sucked into the flow path 64 through the discharge hole 24 is blown away by the air flow (discharge air flow) flowing through the flow path 64. Therefore, the removal waste 80 can be suitably discharged without adding a special configuration to the suction means 60.
According to the method using compressed air, a compressor device generally used in a normal factory may be used, and the configuration can be easily made. The suction means is not limited to this, and other decompression (vacuum) devices may be used.

In the above-described apparatus for drilling a through-hole in a work peripheral wall, the opening of the through-hole 70 in the peripheral wall 15 of the cylindrical part 12 of the work 10 having at least a part of the cylindrical part 12 is caused by shearing or breaking. It can be verified by examining the situation of
Moreover, the above drilling apparatus can be used suitably when forming the through-hole 70 about the workpiece | work consisting of a comparatively highly brittle material like a forge part.

Next, an apparatus system provided with the structure demonstrated above is demonstrated in detail based on FIGS. FIG. 7 is a cross-sectional view showing the state of the apparatus system before the workpiece 10 is set in the press die, and FIG. 8 is a moment at which the workpiece 10 is set in the press die and the through hole 70 is drilled. It is sectional drawing which shows an apparatus system. FIG. 9 is a front view of the press die as viewed from the side to which the workpiece 10 is supplied. In addition, about the structure same as the structure demonstrated above, the same code | symbol is attached | subjected and description is abbreviate | omitted.
A feeder means 81 is configured to suck the work 10 and supply it to the die 20 while being slidably held in the punching direction within the range of the sucked state.

A work supply passage 82 is a passage for sequentially feeding the work 10 to the press die. From the workpiece supply passage 82, the workpiece 10 is sent to a linear guide passage 82a for guiding the movement in the axial direction.
Reference numeral 83 denotes a workpiece discharge passage, which is an opening through which the workpiece 10 having the through hole 70 is discharged.

A cylinder device 85 is fixed to the base 90 as one form of reciprocating means. Thereby, the magnet 87 fixed to the front-end | tip of the expansion-contraction rod 86 can be reciprocated in the axial center direction within the linear guide channel 82a.
The end surface of the magnet 87 is formed on a flat holding surface 87a that holds the workpiece 10 by attracting and attracting it with a magnetic force. Thereby, the workpiece | work 10 can slide in the adsorbed state on the holding surface 87a. That is, the work 10 is held on the holding surface 87a so as to be able to shift (slide) with a relatively small force in a small range.
According to the cylinder device 85, the work 10 is held by the magnet 87, and can be suitably supplied to the die 20 and the punch 30 of the press die by extending.

In addition, although the magnet 87 of this example is comprised with the permanent magnet, as long as it has a required magnetic force, it is good also as an electromagnet.
In this embodiment, the magnet 87 is provided at the tip of the telescopic rod 86 of the cylinder device 85 corresponding to the iron-based workpiece 10, but the means for attracting and holding the workpiece 10 is not limited to this. For example, depending on the form and material of the workpiece 10, the workpiece 10 can be held by being attracted to the holding surface by vacuum suction.

The operation of the feeder means 81 having the above configuration will be described.
First, the workpiece 10 is sent to the linear guide passage 82a through the workpiece supply passage 82 (see arrow (1)).
Then, the workpiece 87 is pushed out to the position where it is set in the press die while being attracted and held by the magnet 87 moving in the direction approaching the press die as the telescopic rod 86 is extended (arrow (2)). reference). As a result, the workpiece 10 is positioned on the die 20 and is in a state of being fitted to the cored bar 32 from which the punch 32 is protruded. The punch 32 and the cored bar 32 are relatively inserted. At this time, the workpiece 10 is held by the magnet 87 and can be supported from below by the workpiece support member 88 and is supported on the inside by the cored bar 32 inserted into the cylindrical workpiece 10. It is in a state that can be done.

In this state, when the lifting block 40 is pressed by the pressing means 50 via the pressure plate 50 a, the lifting block 40 moves in the punching direction against the urging force of the return spring 56. In this embodiment, the elevating block 40 is lowered. At this time, the cored bar 32 and the work support member 88 that are integrally fixed to the lifting block 40 are similarly lowered.
In this embodiment, as shown in FIG. 8, the circumferential groove portion 13 (see FIG. 7) formed on the outer periphery of the workpiece 10 is fitted to the convexly formed die 20 in the descending process of the elevating block 40. The work 10 is also lowered slightly. When the punch 32 comes into contact with the inner peripheral surface of the workpiece 10 and is pressed by the cored bar 32, the workpiece 10 is shifted downward until it contacts the die 20. As a result, the workpiece 10 is positioned on the die 20. At this time, the holding state with respect to the workpiece 10 by the magnet 87 is maintained, and the workpiece 10 is in a state of being slightly lowered by sliding in the plane of the holding surface 87a (see FIG. 7). That is, the work 10 is in a state of being slightly slid in the punching direction while being attracted by the magnet 87 and supplied to the die 20.

  The work 10 is attracted to one end face 10a (see FIG. 7) by a magnet 87 and positioned in the axial direction, and the other end face 10b (see FIG. 7) of the work 10 reciprocates. Not touching. Thereby, the workpiece 10 can be suitably held and the through hole 70 can be formed.

  Then, when the elevating block 40 is further lowered, as shown in FIG. 8, the punch 30 drills a through hole 70 (see FIG. 1 and the like) in the peripheral wall of the workpiece 10. Since the drilling of the through hole 70 has been described in detail above and below (see FIGS. 1 to 6), the description thereof is omitted here.

Next, when the pressing by the pressurizing means 50 is released, the cored bar 32 and the support member 88 are raised together with the lifting block 40 by the return spring 56. Along with this, the work 10 is lifted by slightly sliding the holding surface 87a, and returns to the original position when supplied.
When the telescopic rod 86 contracts, the workpiece 10 attracted and held by the magnet 87 is linearly moved away from the press die (see arrow (3)). Thereby, the workpiece | work 10 can be easily discharged | emitted from a press die.
Thereafter, when the workpiece 10 is moved to the position of the workpiece discharge passage 83, the workpiece 10 is hit by a striking means (not shown) to be released from the attracting and holding state by the magnet 87. As a result, the work 10 is naturally dropped and discharged from the work discharge passage 83 (see arrow (4)).

  According to the feeder means 81 described above, the workpiece 10 can be automatically supplied to a press die having the die 20 and the punch 30 as constituent elements and automatically discharged. Thereby, supply / discharge of the workpiece | work 10 can be automated suitably, and productivity can be improved. In addition, basically, simply by providing a cylinder device or the like as a reciprocating mechanism, the structure is simple and the manufacturing cost of the device can be reduced.

Next, an attachment / detachment mechanism for maintaining and managing the press die of this embodiment will be described.
Reference numeral 39 denotes a press die unit, which includes a lifting block 40 to which the core metal 32 is fixed, a die block 22, a rear wall block 47, a stripper 65, a return spring 56, and the like provided on a base plate 46. ing.
A groove 91 is provided on the base 90 of the apparatus, and the base plate 46 of the press die unit 39 is fitted therein. 91a is an inner surface of the groove, and 91b is an inner bottom surface of the groove.
Reference numeral 95 denotes a pressing member, and reference numeral 95a denotes a slope. Furthermore, 96 is a fixing means, and is provided so as to fix the pressing member 95 in a pressed state.

According to the above configuration, as shown in FIGS. 7 and 8, the base plate 46 is placed on the inner bottom surface 91b of the groove, and one end surface of the base plate 46 is brought into contact with the inner side surface 91a of the groove, thereby The press die unit 39 can be suitably fixed on the base 90 only by being fixed by the pressing member 95 that contacts the other end of the plate 46.
This is because the pressing force by the pressing member 95 becomes a force for bringing the base plate 46 into close contact with both the inner side surface 91a of the inner bottom surface 91b groove and the inner bottom surface 91b of the groove by the inclined surface 95a.
According to this, the press die unit 39 can be fixed by one fixing means 96. Further, the press die unit 39 can be easily detached from the base 90 by loosening the fixing means 96 and sliding it in the direction of arrow E. That is, since it can be attached and detached with one touch, maintenance management is facilitated and production efficiency can be improved.

Next, the stripper mechanism of this embodiment will be described with reference to FIG.
Reference numeral 65 denotes a stripper, which is formed in a gate shape so that it can contact the workpiece 10.
Reference numeral 66 denotes a rotation shaft, and the stripper 65 is provided so as to be rotatable about the rotation shaft 66.
68 is an elastic member for setting, and is arranged between the stripper 65 and the pressure plate 50a in order to set the rotating end side of the stripper 65 in contact with the die block 22 with a required pressing force (see arrow). It is installed. The elastic member 68 may be a urethane spring that has almost no spring vibration.

Reference numeral 69 denotes a reversing spring, which is a spring as an elastic member for reversing the stripper 65 when the pressing plate 50a is lifted and the pressing force by the pressing means 50 is released.
The turning end side of the stripper 65 is lifted by the reversing spring 69, so that the workpiece 10 can be taken in and out of the press die.
According to this stripper mechanism, compared with the case where the stripper is slid up and down, positioning is performed by one rotary shaft 66, so that accuracy is easily obtained, the number of parts is small, and a smaller space can be accommodated. There are advantages.

As described above, the apparatus system related to the drilling of the through hole in the work peripheral wall has been described with reference to FIGS. 7 to 9. However, the present invention is not limited to this embodiment, and other accompanying apparatuses can be provided.
For example, an inspection system for confirming that the through hole 70 has been drilled can be provided. In this case, the presence of the through hole 70 can be confirmed by detecting the leakage of air or detecting the transmission of light using the property of the opening of the through hole 70.

Next, a process of drilling the through hole 70 in the peripheral wall 15 of the cylindrical portion 12 of the workpiece 10 using the drilling apparatus having the above configuration will be described with reference to FIGS.
First, as shown in FIG. 2, the workpiece 10 is positioned on the die 20, and a punch 30 projecting shorter than the thickness of the peripheral wall 15 on the rod-shaped cored bar 32 held in a cantilever manner by the elevating block 40 is formed into a cylinder. It is set as the state inserted in the inside of the shape part 12. FIG.
Although the positioning means provided on the die 20 side is not particularly described here, the system described with reference to FIGS. 7 to 9 and other ordinary techniques may be selectively used as appropriate.

Next, the punch 30 is driven into the peripheral wall 15 of the workpiece 10 from the inside of the cylindrical portion 12 by relatively pressing and moving the punch 30 in the direction close to the die 20 through the cored bar 32. As a result, as shown in FIG. 3, a fracture 19 is generated between the shear 18 and the inner and outer peripheral portions of the peripheral wall 15. At this point, the punch 30 has been driven halfway, leaving a further driving distance.
As shown in FIG. 3, this moment is a momentary state in which the punched residue 80 is separated from the peripheral wall of the workpiece 10 due to the break 19, and the through hole 70 is provided, but the punched residue 80 is still in the through hole 70. It exists in the state. In this state, the through hole 70 itself is formed and is in a drilled state.
Then, since the punched residue 80 is broken and separated as described above, the applied pressure from the punch 30 is released all at once. As a result, in addition to the continuous movement that moves in the direction in which the punch 30 is driven, the movement of releasing the “bending” of the core metal 32 and the movement of the elastic means 54 are added. Therefore, the punch 30 is rapidly lowered in a short time. As a result, the punch 30 impactively pushes the punched residue 80 into the discharge hole 24 of the die 20.

Next, when the through hole 70 is drilled as described above, the punched residue 80 is removed by suction from the punched residue discharge hole 24 of the die 20 by the suction means 60, and the through hole 70 is opened.
As described above, at this time, the drawn residue 80 is suitably pushed downward, so that the suction action works suitably. Thereby, the extraction residue 80 can be reliably discharged. For this reason, it is not necessary to remove the punched residue 80 in a separate process, and productivity can be improved.
According to this embodiment, since the punch 30 is driven from the inside and the through hole 70 is opened, no burr is generated on the inner peripheral surface of the cylindrical portion 12.
Further, it is not necessary for the punch 30 to pierce the peripheral wall 15 of the workpiece 10 as in normal press punching. In this embodiment, the punch 30 having a length about half the thickness of the peripheral wall 15 can be opened by drilling the through hole 70 and removing the punched residue 80.
For this reason, it is possible to extend the life of the mold, improve the productivity, and greatly reduce the processing cost.

Next, with reference to FIGS. 2 to 4 based on FIG. 10, a method for forming the through hole 70 in the peripheral wall 15 of the workpiece 10 in a two-step pressing process will be described.
First, as shown in FIG. 10 (a), before the through hole 70 is drilled, the punch 10 is crushed on the peripheral wall 15 of the workpiece 10 from the outside of the cylindrical portion 12 corresponding to the planned drilling position of the through hole 70. (Not shown) is formed to form a recess 17 that is a peripheral edge that is slightly larger than the through hole 70.
As in the state shown in FIG. 2, the workpiece 10 is positioned on the die 20, and the punch 30 is protruded shorter than the thickness of the peripheral wall 15 on the rod-shaped cored bar 32 held in a cantilever manner by the elevating block 40. Is inserted into the inside of the cylindrical portion 12.
Next, as in the state shown in FIG. 3, the punch 30 is moved from the inside of the cylindrical portion 12 to the workpiece 10 by relatively pressing and moving the punch 30 in the direction close to the die 20 through the cored bar 32. It is driven into the peripheral wall 15. By this step, as shown in FIG. 10B, a shear 19 and a break 19 reaching the peripheral edge 17a of the recess 17 are generated.

The punching residue 80 at the moment when the punch 30 is maximally driven is a movement in which the above-described “bending” of the cored bar 32 is released as in the case of the embodiment described with reference to FIGS. The movement by the elastic means 54 is added, and it is shockedly pushed out to the discharge hole 24 of the die 20. As a result, the punched residue 80 is completely separated from the through hole 70.
Next, similarly to the state shown in FIG. 4, the punched residue 80 is removed by suction from the punched-out hole 24 of the die 20 by the suction means 60, and the through hole 70 is opened as shown in FIG. Is done.
Similar to the above-described embodiment, at this time, the punched residue 80 is suitably pushed downward, so that the suction action works favorably. Thereby, the extracted residue 80 can be reliably discharged.
According to this drilling method, the through hole 70 can be suitably drilled even with a relatively thick peripheral wall 15. Moreover, since the dent part 17 was formed first, not only the inner peripheral surface but also the outer peripheral surface does not generate burrs. Therefore, no post-process such as barrel polishing is required.
Further, even in the form of this method, it is not necessary for the punch 30 to pierce the peripheral wall 15 of the workpiece 10 as in the case of normal press punching. The punch 30 having a length about half the wall thickness of the peripheral wall 15 can be opened by drilling the through hole 70 and removing the punched residue 80. Further, a separate process for removing the punched residue 80 is not required.
For this reason, the life of the mold can be extended, the productivity can be improved, and the processing cost can be greatly reduced.

Moreover, the recessed part 17 is not limited to being formed by the press process as demonstrated above. For example, you may form the recessed part 17 by means other than press, such as cutting by a drill and electrical discharge machining. Furthermore, instead of the dent portion 17 formed by post-processing, the dent portion 17 provided in advance by mold forming (molding processing) such as a cast product may be used.
By providing the recess 17 in this manner, the thickness of the peripheral wall 15 in which the through hole 70 is to be provided becomes substantially thin, and can be drilled with a small pressing force.
At this time, the inner corner of the recess 17 functions as a portion where stress concentration occurs, and the break 19 is likely to occur. Thereby, the through-hole 70 can be easily drilled with a smaller pressing force.
Moreover, when the recessed part 17 is formed in the outer side of the cylindrical part 12 in processes other than a press, there is no problem which an internal peripheral surface deform | transforms. On the other hand, when the hollow part 17 is formed by pressing the cylindrical part 12 from the outside, the inner peripheral surface may be deformed by the pressed meat.

In addition, when the punch is driven from the inside of the cylindrical portion 12 and the through hole 70 is drilled, the diameter and depth of the recessed portion 17 are determined so as to secure a thickness at which the shear 18 and the fracture 19 are generated. Good.
In this manner, by providing the recess 17 on the outer peripheral portion of the cylindrical portion 12 by some method and punching with the punch 30 from the inside, it is possible to prevent burrs from occurring on both the inside and the outside of the cylindrical portion 12. Moreover, since the punching can be performed with a small pressing force, the life of the punch 30 can be significantly increased.
By the way, the shape of the recessed portion 17 is not limited to the shape having the circular inner bottom shown in FIG. 10A, and for example, the outer periphery may be a ring-shaped groove corresponding to the diameter of the through hole 70. Good. That is, it is only necessary that the thickness of the portion where the through hole 70 is provided is substantially reduced and the recess 17 has a notch-like function that easily causes stress concentration.

FIG. 24 is a cross-sectional view showing an example in which a recessed portion 17 is provided in advance on the outer peripheral portion of the cylindrical portion 12 by a method other than pressing in order to make the through hole 70 in the workpiece 10 having the thick peripheral wall 15. FIG. 24A shows a state in which the punch 30 has been driven into the peripheral wall 15, and FIG. 24B shows a state in which the through hole 70 is opened.
In this example, as shown in FIG. 24 (b), a spot facing portion 17 b is provided, and about 2/3 of the remaining thickness of the peripheral wall 15 is cut by a drill and formed in the recess portion 17. Further, about 1/3 of the remaining thickness of the peripheral wall 15 is formed by driving the punch 30.
According to this, even in the workpiece 10 having the thick peripheral wall 15, the through hole 70 can be suitably opened as described above. In particular, the present invention can be suitably applied to fields where precision machining has been conventionally performed by electric discharge machining or the like. 24, the thickness of the peripheral wall 15 is about 2.5 mm, the diameter of the through hole 70 is about 1 mm, the cutting depth by the drill is about 1 mm, and the thickness perforated by the punch 30 is 0.00. It is 5 mm, and a through hole 70 is opened in a small metal part.
In addition, as shown to Fig.24 (a), the convex die | dye 20 fits into the concave spot facing part 17b, and the workpiece | work 10 is positioned in this example. In addition, the die 20 is provided with a slightly smaller inner diameter at a portion slightly below the upper end in the drawing, and a punching piece 80 is fitted and held in that portion. Thereby, dregs rise can be prevented.

Next, an apparatus for punching and opening a through hole by punching a punch into a drilled portion of a work peripheral wall in a plurality of stages will be described in detail with reference to FIGS.
This device is also a device for drilling a through hole 70x (see FIG. 28) by press punching in the peripheral wall 15x of the cylindrical portion 12x of the workpiece 10x having at least a portion of the cylindrical portion 12x. It has basically the same components as the device. Therefore, the same components as those described above are denoted by the same reference numerals and description thereof is omitted.
The workpiece 10x in the illustrated embodiment is a small forged part in which the inner diameter of the cylindrical portion 12x is about 5 mm and the thickness of the peripheral wall 15x of the drilled portion is about 1.6 mm.

Reference numeral 30x denotes a first punch, and as shown in FIG. 25, a rod-shaped first cored bar 32x held in a cantilever manner is protruded shorter than the thickness of the peripheral wall 15x.
For example, the first punch 30x in the illustrated embodiment is fixed to the distal end portion of the first metal core 32x so as to protrude about 0.8 mm from the peripheral side surface. The rear end side is press-fitted and fixed in the hole 35x provided in the first metal core 32x so that the front end side of the cylindrical first punch 30x protrudes in a direction perpendicular to the axis of the first metal core 32x. Has been. The diameter of the first punch 30x is about 1.3 mm.

As shown in FIGS. 25 and 26 (a), the first punch 30x is inserted into the cylindrical portion 12x via the first cored bar 32x and relatively close to the die 20x. It is moved under pressure. Thereby, half-cutting is performed so that the concave portion 15y is formed on the inner wall surface and the convex portion 15z is formed on the outer wall surface by being driven into the peripheral wall 15x from the inside of the cylindrical portion 12x and causing shearing. Do. FIG. 26A shows a cross section cut in parallel to the axis and a cross section cut in a direction perpendicular to the axis.
At this stage, it is in a half-cut state (see FIG. 26B), and most of the inner peripheral side surface of the concave portion 15y and the outer peripheral side surface of the convex portion 15z are shear surfaces. Thus, since the punching operation is stopped at the stage of shearing, the load applied to the first punch 30x can be limited. Accordingly, the first punch 30x is smaller in diameter than the thickness of the workpiece 10x, but is not easily damaged. Its life can be extended and productivity can be improved. In addition, FIG.26 (b) is a principal part expanded sectional view of Fig.26 (a).

Reference numeral 30y denotes a second punch, and as shown in FIG. 27, a rod-shaped second cored bar 32y held in a cantilever manner is protruded shorter than the thickness of the peripheral wall 15x and longer than the first punch 30x. And a small diameter.
For example, the second punch 30y in the illustrated embodiment is fixed to the distal end portion of the second cored bar 32y so as to protrude about 1.1 mm from the peripheral side surface thereof. The rear end side is press-fitted and fixed in the hole 35y provided in the second metal core 32y so that the front end side of the cylindrical second punch 30y protrudes in a direction perpendicular to the axis of the second metal core 32y. Has been. Further, the diameter of the second punch 30y is set to about 1.15 mm.
By the way, the small diameter means not only that the diameter of the circular cross section is small, but also that the cross section is slightly smaller. Therefore, the shape of the through hole 70x is not limited to a circle, and includes, for example, an oval shape or a long hole shape.

As shown in FIGS. 27 and 28 (a), the second punch 30y is inserted into the cylindrical portion 12x via the second cored bar 32y, and is relatively moved in the direction close to the die 20x. It is moved under pressure. Thereby, the through hole 70x is formed by being driven into the concave portion 15y from the inside of the cylindrical portion 12x and finally causing breakage.
The work using the second punch 30y and the first punch 30x uses the same die 20x. For this reason, as shown in FIG. 28B, the second punch 30y can be driven accurately into the center of the recess 15y.
When the second punch 30y is driven into the inner bottom surface of the recess 15y, a new shear occurs in the portion where the second punch 30y is driven, and a large fracture occurs following the shear (see FIG. 28B). Thereby, the through hole 70x is substantially drilled.
Since the second punch 30y is provided with a smaller diameter than the first punch 30x, the press pressure is reduced by the smaller area of the tip surface of the punch. Further, as shown in FIG. 28 (b), the second punch 30y is driven in a state in which the outer peripheral side surface thereof is not pressed against the inner peripheral side surface of the recess 15y, so that the sliding resistance is small. Therefore, the load applied to the second punch 30y is small, and even if it is formed thinner and longer than the first punch 30x, it is not easily damaged. Its life can be extended and productivity can be improved.

Reference numeral 30z denotes a third punch. As shown in FIG. 29, a rod-shaped third cored bar 32z held in a cantilever manner is projected longer than the second punch 30y and has a small diameter. .
For example, the third punch 30z in the illustrated embodiment is fixed to the tip end portion of the third cored bar 32z so as to protrude from the peripheral side surface by about 1.25 mm. The rear end side is press-fitted and fixed in the hole 35z provided in the third metal core 32z so that the front end side of the cylindrical third punch 30z protrudes in a direction perpendicular to the axis of the third metal core 32z. Has been. The third punch 30z has a diameter of about 1 mm.

As shown in FIGS. 29 and 30A, the third punch 30z is inserted into the cylindrical portion 12x via the third cored bar 32z and relatively close to the die 20x. It is moved under pressure. As a result, the through hole 70x is opened from the inside of the cylindrical portion 12x by being driven into the through hole 70x provided by the second punch 30y, and by removing the punched residue 80x.
At this time, the second punch 30y is ruptured, and the third punch 30z is driven into the place where the through hole 70x is completely or almost completely drilled. Therefore, the load applied to the third punch 30z is smaller than other punches. For this reason, the third punch 30z may be formed narrower and longer than the other punches, and the third punch 30z can be reliably discharged by flipping the punched residue 80x (see FIG. 30B).

Reference numeral 20x denotes a die, which is one die for the punches 30x, 30y, and 30z in a set of dies for press-working the workpiece 10x.
In the present invention, since the first punch 30x and the second punch 30y are constituent elements, at least two punches are provided, whereas there is one die 20x. Furthermore, in this embodiment, the third punch 30z is provided, but there is one die 20x. The workpiece 10x set on the one die 20x is held on the die 20x until a series of drilling processes are completed.

Thus, the following effects can be obtained by performing the drilling process divided into a plurality of stages in a state where the workpiece 10x is fixed to one die 20x.
As shown in FIG. 26, when the half-cut is performed by the first punch 30x, the convex portion 15z is fitted into the hole 24 of the die 20x. Thereby, positioning with extremely high accuracy is performed for the concave portion 15y on the opposite side of the convex portion 15z.
Further, as shown in FIG. 28, even when the through hole 70x is formed by the second punch 30y, the punched residue 80x is fitted in the hole 24 of the die 20x. Thereby, the positioning of the through hole 70x corresponding to the punched residue 80x is also performed with extremely high accuracy.
Accordingly, the second punch 30y and the third punch 30z can be driven with extremely high accuracy in each of the work steps shown in FIGS.

Next, a mechanism for setting the punches 30x, 30y, and 30z for making the through holes 70x will be described with reference to FIGS. 31 and 32. FIG.
As described above, 32x, 32y, and 32z are rod-shaped cores, and punches 30x, 30y, and 30z are provided corresponding to the respective rods.
Reference numerals 31x, 31y, and 31z denote punch holders. As shown in FIG. 31, corresponding cores 32x, 32y, and 32z protrude from the end portions where the punches 30x, 30y, and 30z are provided. Hold in the state. The punch holders 31x, 31y, 31z are provided with holding holes 42a having the same structure as the holding holes 42 of the lifting block 40 described above, and hold the core bars 32x, 32y, 32z in a detachable manner.

40a is a slide block, and each punch holder 31x, 31y, 31z is detachably held. One is provided for each punch holder 31x, 31y, 31z, and is guided by a guide block 47a so as to be slidable back and forth in the press punching direction.
The slide block 40a has the same configuration as the above-described lifting block 40, and holds the core bars 32x, 32y, and 32z in a detachable manner through punch holders 31x, 31y, and 31z.

Reference numeral 52 denotes a pressurizing device, which pressurizes the slide block 40a to move the punches 30x, 30y, 30z in the press punching direction via the punch holders 31x, 31y, 31z and the core bars 32x, 32y, 32z.
The pressure device 52 is indispensable as a driving device for the slide block 40a, but it is needless to say that the configuration of the pressure means 50 including the pressure device 52 may be adopted as appropriate.

Reference numeral 72 denotes a punch holder feeding mechanism. As shown in FIG. 31, a frame body portion 73 is provided that guides the punch holders 31x, 31y, and 31z so that they can be held in parallel, and can be moved in the attaching / detaching direction with respect to the slide block 40a. Moreover, the drive device 74 which sends each punch holder 31x, 31y, 31z sequentially to the predetermined position for attaching or detaching with respect to the slide block 40a is provided.
The driving device 74 sends the frame body portion 73 in a direction orthogonal to the mounting direction of the punch holders 31x, 31y, 31z to the slide block 40a. The punch holder feeding mechanism 72 including the driving device 74 is disposed on the back side of the guide block 47a. The punch holders 31x, 31y, and 31z are arranged so as to be able to be inserted into the holding holes 40b of the slide block 40a through the through-hole 47b provided in the guide block 47a.

Reference numeral 75 denotes a punch holder attaching / detaching mechanism. As shown in FIGS. 31 and 32, the punch holders 31x, 31y, 31z sent to a predetermined position are reciprocated with respect to the slide block 40a to be attached / detached.
Reference numerals 77x, 77y, and 77z denote sliders each having a claw-like engaging portion 77a at the tip. This engaging part 77a is provided so that it may fit in the to-be-engaged part 31a provided in the rear end of each punch holder 31x, 31y, 31z. The engagement relationship allows each punch holder 31x, 31y, 31z to move in the vertical direction. Reference numeral 78 denotes a driving device, which is a driving source for sliding the sliders 77x, 77y, and 77z.
According to this, each of the punch holders 31x, 31y, and 31z can be sequentially attached to and detached from and replaced with the slide block 40a by sliding the sliders 77x, 77y, and 77z sequentially in cooperation with the feed mechanism 72 of the punch holder. .
According to the above mechanism, replacement of the punches 30x, 30y, and 30z in each process can be automated, and productivity can be improved.

Next, based on FIGS. 25 to 32, a method for punching and opening a through hole by punching a punch into a drilled portion of a work peripheral wall in a plurality of stages will be described.
In this method of drilling a through hole in the work peripheral wall, the work 10x is positioned on the die 20x, and the punch is protruded shorter than the thickness of the work peripheral wall 15x on the bar-shaped metal cores 32x and 32y held in a cantilever manner. 30x and 30y are inserted into the inside of the cylindrical portion 12x (see FIGS. 25, 27, and 29), and the punches 30x and 30y are relatively pressed in the direction close to the die 20x through the core bars 32x and 32y. By moving the punch 30x, 30y, the process of driving the punch hole 30x into the peripheral wall 15x from the inside of the cylindrical portion 12x is divided into two stages.

First, in the first stage, the first punch 30x is driven into the peripheral wall 15x to cause shearing, so that the concave portion 15y is formed on the inner wall surface and the convex portion 15z is formed on the outer wall surface. Cut is performed (see FIG. 26).
Next, in the second stage, the second punch 30y that protrudes longer than the first punch 30x and is formed with a small diameter is driven into the recess 15y to finally cause breakage to form the through hole 70x. (See FIG. 28).
Then, as a third step subsequent to the two-step process of drilling the through hole 70x, the third punch 30z that protrudes longer than the second punch 30y and has a small diameter is attached to the cylindrical portion 12x. The through-hole 70x is opened by driving into the through-hole 70x from the inside to eliminate the punched residue 80x (see FIG. 30).
The above steps are performed using the same die.

According to this press punching method and apparatus, the through hole 70x having a diameter smaller than the thickness of the workpiece 10x can be suitably drilled and opened. And as demonstrated above, the lifetime of a punch can be extended and productivity can be improved.
Moreover, this invention is not limited to the workpiece | work 10x provided with a surrounding wall, It can apply also to the workpiece | work of another form. That is, there is an essence in punching / opening a through-hole by driving a punch into a workpiece from the same direction in a plurality of stages. At this time, the diameter of the punch is gradually reduced, and the protrusion length of the punch is gradually increased. In particular, this is an excellent technique for making small through holes in a thick material. For this reason, it is needless to say that the present invention can also be applied to the case of press punching in which a through hole is formed in a plate material or the like. In that case, the core metal held in a cantilever manner does not need to be a component.

Next, an example of a method for drilling a through hole and a drilling device in a work peripheral wall that can use the embodiment described above will be described in detail.
In this embodiment, the workpiece 107 to be processed is a body 107a of a hydraulic valve lifter shown in FIG. 22, and a through hole 170 is formed in the peripheral wall 172 of the cylindrical portion 171 of the body. The front part of the cylinder part 171 is closed.
A stepped portion 173 inclined around the outer surface of the cylindrical portion 171 in the axial direction is formed at the planned opening of the through hole.
The outer diameter of the cylindrical portion 171 is about 16 mm, the inner diameter is about 10 mm, the length is about 40 to 50 mm, and the diameter of the through hole 170 is slightly smaller than the wall thickness of the cylindrical portion 171.

FIG. 11 shows the order of processing steps. In the crushing step shown in FIG. A, the crushing punch 131 is driven from the outside of the cylindrical portion peripheral wall 172 toward the axial center of the cylindrical portion 171 (more precisely, “workpiece 107 C) and dents 174 are formed lower than the lower part of the step part 173. The diameter D of the recess 174 is slightly larger than the diameter of the through hole 170.
The front end portion (upper end portion) of the crushing punch 131 is formed in a short cylindrical shaft portion 131a, and the front end surface is a flat surface orthogonal to the cylindrical axis.
The inner peripheral surface of the dent 174 is a shear surface 175 that has been sheared by the tip shaft 131 a of the crushing punch 131.
When the distal end shaft portion 131 a of the crushing punch 131 bites into the peripheral wall 172, a presser punch 151 that prevents the wall of the peripheral wall 172 from bulging from the inside is applied to the inner surface of the peripheral wall 172.
In the drilling step shown in FIG. b, a bottomed hole 176 is opened by driving a drilling punch 152 from the inside of the cylindrical portion peripheral wall 172 toward the radially outer side of the cylindrical portion at a position corresponding to the recess 174. When the punching punch 152 is driven into the peripheral wall 172, the work 107 is received by the die block 103.
The diameter of the punch punch 152 is slightly smaller than the diameter of the recess 174.
The inner peripheral surface of the bottomed hole 176 is also a sheared surface that is sheared by the perforating punch 152.
The pushed bottom 177 of the meat 178a enters the recess 174 and slightly protrudes from the opening edge of the recess 174 on the lower side of the inclined step 173.
In the perforation process shown in FIG. c, by punching the perforation punch 153 into the bottomed hole 176 from the inside of the cylindrical portion peripheral wall 172 toward the outside in the radial direction of the cylindrical portion, the bottom portion of the bottomed hole 176 is punched out to the outside. 170 is established.
When the punching punch 153 is driven into the bottomed hole 176, the work 107 is received by the die block 103.

FIG. 12 shows a state in which the punching units 111, 112, and 113 are arranged in the first station S1 that performs the crushing process, the second station S2 that performs the drilling process, and the third station S3 that performs the drilling process, respectively. .
Each punching unit 111, 112, 113 includes a die block 103 and a cored bar 105. Punches 151, 152, and 153 are provided on each core bar 105 so as to protrude downward.
The work cylinder part 171 is fitted to the cored bar 105 located above the die block 103, the cored bar 105 is lowered, the work 107 is received by the die block 103, and the punches 152 and 153 are inserted from the inside of the cylindrical part 171 of the work 107. It is driven into the peripheral wall 172. However, in the first station S <b> 1 where the crushing process is performed, the presser punch 151 is only pressed against the inner surface of the work cylinder portion 171, but is not driven into the peripheral wall 172, and is recessed by the crushing punch 131 on the outer peripheral surface corresponding to the presser punch 151. A portion 174 is formed.
As shown in FIGS. 13, 14, and 15, each of the punching units 111, 112, and 113 has a die block 103 and a cored bar 105 mounted on a common base 101 via a mounting base 102.
The mounting base 102 has a right wall plate 122 and a left wall plate 123 projecting from the rear portion of the bottom plate 121, and the rear wall plate 124 is closed between the rear ends of the left and right wall plates 122 and 123.

The die block 103 is placed on the front portion of the bottom plate 121 of the mounting base 102 and is bolted to the wall plates 122 and 123 across the right wall plate 122 and the left wall plate 123.
In the center of the upper surface of the die block 103, a shallow groove portion 130 corresponding to the outer periphery of the work 107 is formed in the front-rear direction so that the work 107 can be stably received (FIGS. 20 and 21).
Further, when the workpiece 107 is received by the groove portion 130 in the die block 103, a vertical hole 132 having a reduced diameter at the upper end is formed at a position corresponding to the position where the workpiece 107 is to be opened.

As shown in FIG. 12A, a shaft-shaped crushing punch 131 is inserted into the vertical hole 132 of the die block 103 of the first station S1, and the crushing punch 131 has a square upper end periphery, and a concave portion 174 of the work 107. The upper end protrudes upward from the groove 130 corresponding to the depth of the recess 174.
As described above, the front end portion (upper end portion) of the crushing punch 131 is formed in a short cylindrical shaft portion 131a, and the front end surface is a flat surface orthogonal to the cylindrical shaft core.
The crushing punch 131 is supported by a receiving base 133 provided on the bottom plate 121 of the mounting base 102 and is prevented from moving downward.

As shown in FIGS. 13 and 15, the elevating block 104 is arranged to be movable up and down in a space surrounded by the three wall plates 122, 123, and 124 of the mounting base 102 and the die block 103.
A cored bar mounting hole 141 is formed in the upper part of the elevating block 104 in the front-rear direction, and the shaft-shaped cored bar 105 is inserted into the cored bar mounting hole 141 leaving the front part. The protruding portion of the cored bar 105 from the lifting block 104 is positioned directly above the groove 130 of the die block 103.
The elevating block 104 is provided with a spring accommodating hole 142 from the bottom side and is urged upward by a spring 144 accommodated in the spring accommodating hole 142. The raising / lowering block 104 in the raised position can be lowered by the gap between the bottom surface of the block and the bottom plate 121 of the mounting base 102. The rising end height of the lifting block 104 is regulated by a rising end regulating means (not shown).
The spring 144 is supported by a spring pressure adjustment base 145 screwed to the bottom plate 121 of the mounting base 102, and the spring pressure can be adjusted by tightening or loosening the adjustment base 145.
The elevating block 104 has a crank bolt 143 that reaches the cored bar mounting hole 141 on the side of the block, and the cored bar 105 can be fixed by tightening the crank bolt 143.
The punches 151, 152, and 153 projecting from the metal cores 105 are configured so that the cylindrical portion 171 of the workpiece 107 is fitted to the metal core 105 and the opening-side end surface of the cylindrical portion 171 is in contact with the lifting block 104. It corresponds to the planned opening position of through holes.

  The base 101 is fixed to a base (not shown) of the press device, and the lifting blocks 104 are all lowered from the standby position against the spring 144 by the lowering of the ram (not shown) of the press device. Will rise to the standby position all at once by the spring force.

A stripper 106 is provided in the die block 103 of the second station S2 and the third station S3.
The stripper 106 has a contact plate 162 projecting from a block body 161 fixed to the upper surface of one end of the die block 103 with a bolt toward the upper portion of the core metal 105.

As shown in FIG. 16, a cut portion 150 that lowers the cored bar 105 in the height direction is formed at the upper end on the tip side of each cored bar 105 corresponding to the portion W that fits into the cylindrical part 171 of the workpiece 107. . As shown in FIGS. 17 and 18, the cut portion 150 is cut in an arc shape along the inner peripheral surface of the work cylinder portion 171.
A press punch 151 is formed on the core metal 105 of the first station S1, a punch punch 152 is formed on the core metal 105 of the second station S2, and a punch punch 153 is formed on the lower die block 103 on the core metal 105 of the third station S3. It protrudes downward at a position directly above 132.
The peripheral edge of the punching side of each punch is angular.
As shown below, although the lengths of the presser punch 151, the punch punch 152, and the punch punch 153 are different, as shown in FIGS. 16 and 17, from the cut portion 150 of each cored bar 105 to the tips of the punches 151, 152, and 153 The distance H1 is substantially uniform within a range in which the workpiece 107 can be inserted into and removed from the cylinder portion 171. When the protrusion length of the punch increases, the depth H2 of the cut portion 150 of the cored bar 105 increases.

As described above, the press punch 151 of the first station S1 is formed on the inner surface of the peripheral wall 172 when the tip shaft 131a of the crushing punch 131 is driven from the outside of the cylindrical peripheral wall 172 of the workpiece 107 to form the recess 174. This is to prevent the meat from bulging locally.
If the peripheral surface of the cored bar 105 is in contact with the inner surface of the peripheral wall 172, the presser punch 151 can be omitted.
In the case of the embodiment, as shown in FIG. 22, there is a slight step 180 on the inner surface of the cylindrical portion 171 of the workpiece 107, and the circumferential surface of the cored bar 105 cannot be applied to the through hole opening planned position. A presser punch 151 having a length is protruded from the circumferential surface of the cored bar 105.
It is desirable that the tip diameter of the press punch 151 be able to press the range of the inner surface of the peripheral wall 172 beyond the range corresponding to the recess 174. The tip diameter of the press punch 151 is larger than the diameter D of the recess 174. is there.

  The diameter of the punch 52 in the second station S <b> 2 is slightly smaller than the diameter of the recess 174, and the length can be driven to about ½ of the wall thickness of the cylindrical peripheral wall 172.

  The diameter of the punching punch 153 of the third station S3 is slightly smaller than the diameter of the punching punch 152 of the second station S2, that is, slightly smaller than the diameter of the bottomed hole 176 of the workpiece 107, and the length is bottomed. The length of the hole 176 is punchable. It is not necessary for the tip of the punching punch 153 to reach the bottom of the recessed portion 174 of the workpiece 107. When the punching punch 153 is driven to a depth approaching the bottom of the recessed portion 174, the through hole 170 is opened.

Although it is essential that the diameter D of the recess 174 is larger than the diameter of the punching punch 153, how much larger the diameter D depends on the diameter of the punching punch 153, the material, the thickness of the workpiece 107, and the depth of the bottomed hole 176. Although it varies depending on the conditions such as the above, it has been empirically understood that the following formula can be used.
Recessed portion diameter D = Drilling punch diameter + {2 × (plate thickness × 5-12%)}
If the diameter of the recess 174 deviates from the above formula and is too large or too small, the effect of not generating burrs cannot be obtained.

Accordingly, the lifting block 104 is lowered while the cylindrical portion 171 of the work 107 is fitted to the core bar 105 of the first station S1 until the opening edge of the cylindrical portion hits the lifting block 104. At the same time as the presser punch 151 on the mandrel 105 presses the cylindrical portion peripheral wall 172 (FIG. 19A), the tip shaft portion 131a of the crushing punch 131 is driven into the through hole opening planned position to form a recess 174. (FIG. 11 (a)).
What is important here is that the inner peripheral surface 175 of the recessed portion 174 becomes a shear surface 175 because the peripheral edge of the tip shaft portion 131 a of the crushing punch 131 is angular. Further, since the tip end surface of the shaft portion 131a is a flat surface orthogonal to the axis, the bottom surface of the recessed portion 174 is formed flat.

The work 107 having the recess 174 formed in the first station S1 is removed from the cored bar 105, and the cylindrical part 171 of the work 107 is opened to the cored bar 105 of the second station S2 with the recessed part 174 facing downward. The raising / lowering block 104 is lowered | hung with the edge fitted to the raising / lowering block 104 in the state fitted.
A perforated punch 152 on the mandrel 105 is driven into the position corresponding to the recessed portion 174 from the inside of the cylindrical peripheral wall 172 (FIG. 19B), and a bottomed hole 176 is opened (FIG. 11B). )).
The bottom portion 177 of the pushed meat 178a enters the recess 174 and slightly protrudes from the opening edge of the recess 174 on the bottom side of the step portion 173. The protruding portion 177 escapes into the hole 132 of the die block 103.
The inner peripheral surface of the bottomed hole 176 is a shear surface.
When the elevating block 104 moves up to the standby position, the workpiece 107 hits the contact plate 162 of the stripper 106, and the punching punch 152 comes out of the bottomed hole 176, so that the workpiece 107 can be detached from the cored bar 105.

The work 107 having the bottomed hole 176 formed in the second station S2 is removed from the cored bar 105, and the cylindrical part 171 of the work 107 is fitted into the cored bar 105 of the third station S3 until the cylindrical part opening edge hits the lifting block 104. In this state, the elevating block 104 is lowered with the opening of the bottomed hole 176 facing upward (FIG. 19 (c)).
A perforation punch 153 on the mandrel 105 punches the bottom of the bottomed hole 176 to open a through hole 170 (FIG. 11C).
As shown in FIG. 12C, the punched residue 178 is discharged to the outside from the hole 132 of the die block 103 through the hole 128 of the mounting base 102 and the hole 110 of the base 101.
When the elevating block 104 moves up to the standby position, the work 107 hits the contact plate 162 of the stripper 106 and the punching punch 153 comes out of the work 107.

When the bottom of the bottomed hole 176 is punched, on the punch punching side, the fracture surface of the meat due to punching is continuous with the inner peripheral surface 175 due to the shearing of the recess 174, so that the meat of the peripheral surface 175 faces outward. It will not be pulled out. That is, no burr is generated at the hole edge.
For this reason, the processing process for deburring like the conventional press punching and opening of the through-hole by a drill can be eliminated.
Further, the punching of the press requires a shorter processing time than the opening of the through hole by electric discharge machining, and the productivity can be improved.
Further, since the concave portion 174 having a diameter slightly larger than the diameter of the through hole 170 to be punched is formed in advance on the opposite side of the punching punch 153 from the driving side, the length of the punching punch 153 corresponds to the depth of the concave portion 174. Therefore, the punching punch 153 can be prevented from being broken and the life can be extended.

  Since the bottom surface of the recessed portion 174 on the outer peripheral surface of the cylindrical portion 171 is flat, there is no stepped portion at the position where the through hole is to be opened. For this reason, it is possible to prevent the punch from being shortened due to an unbalanced load acting on the punch driven into the peripheral wall 172 from the inside of the cylindrical portion 171.

  The movement of the work 107 between the stations S1, S2, and S3 and the insertion of the work cylinder 171 into each core bar 105 can be performed manually, but if it is automatically performed by a transfer device (not shown), the work efficiency is improved. Of course, this can be further improved.

A specific example will be described below.
The cylindrical portion 171 has an outer diameter of 16 mm, an inner diameter of 10 mm, and a length of 40 mm.
In FIG. 11A, the thickness t1 on the high side is 3 mm, the thickness t2 on the bottom side is 2.5 mm, and the crushing punch 131 is driven by the step 173 on the outer peripheral surface of the cylindrical peripheral wall 172. The diameter D of the recessed portion 174 is 2.2 mm, and the depth L1 of the recessed portion 174 is 0.5 mm on the thin side.
In FIG. 12B, the diameter of the hole punch 152 is 1.75 mm, and the depth L2 of the bottomed hole 176 formed by the hole punch 152 is 0.9 mm.
In FIG.12 (c), the diameter of the punching punch 153 is 1.70 mm.
A through-hole 170 in which no burr was generated could be opened.

In the embodiment, the die blocks 103 of the stations S1, S2, and S3 have the same shape in order to have compatibility. That is, although the shape of the hole 132 penetrating in the vertical direction of the die block 103 is common, the die block 103 of the second station S2 is not the through hole 132 but is driven by the punching punch 152, so that the cylindrical peripheral wall 172 It is only necessary to form a dent for escaping the meat slightly protruding from the opening edge of the dent portion 174.
The shape of the hole 132 of the die block 103 of the third station S3 is not limited as long as it has a function of discharging the punched residue 178.

In addition, after opening the dent part 174 in the outer peripheral surface of the workpiece | work cylinder part 171, this invention includes punching and opening a through-hole at once to the corresponding position with the dent part 174 from the inner side of the cylinder part 171. Of course.
In this case, the productivity is improved by reducing one machining step, but the punching thickness becomes large and the load load increases, which is disadvantageous for the durability of the punch.

By the way, in order to prevent the cutting edge of the punch 30 from impactingly contacting the workpiece 10, a material having a hardness lower than that of the workpiece 10 may be interposed between the workpiece 10 and the punch 30.
For example, when the workpiece 10 has a cylindrical portion 12 made of cast iron that is hard and brittle, it is preferable to provide an inner wall layer of a metal material or resin material that is softer than the workpiece 10 and has a high spreadability.
The inner peripheral wall layer may be provided as thin as possible within a range in which the impact applied to the punch 30 can be mitigated, and may be removed after drilling.
Moreover, when providing the said inner peripheral wall layer with a resin material, you may form by apply | coating to the internal peripheral surface of the cylindrical part 12 of the workpiece | work 10. FIG.

Although the case where the circular through hole is drilled has been described in the above embodiment, the present invention is not limited to this, and can be applied to the case of drilling an elliptical or oval through hole.
In addition, the material of each component such as punch, die, and cored bar is appropriately selected from known materials according to the specification conditions in order to obtain a suitable mold with high drilling accuracy and long life. That's fine. Furthermore, with respect to punches and dies, a known surface hardening technique may be used as necessary to improve the durability.
As described above, the present invention has been variously described with reference to preferred embodiments. However, the present invention is not limited to these embodiments, and many modifications can be made without departing from the spirit of the invention. Of course you get.

It is sectional drawing which shows one form of the drilling apparatus concerning this invention. It is sectional drawing explaining the insertion process of the punch by the drilling apparatus of FIG. It is sectional drawing explaining the drilling process by the drilling apparatus of FIG. FIG. 7 is a cross-sectional view for explaining a punching waste discharging process by the punching device of FIG. It is the front view (a) and bottom view (b) which show one form of a punch. It is sectional drawing which shows one form of a negative pressure suction device. It is sectional drawing which shows the drilling apparatus system containing the structure which supplies a workpiece | work. It is sectional drawing which shows the state at the time of a through-hole being pierced by the form example of FIG. It is the front view of the press metal mold | die of the drilling apparatus seen from the workpiece | work supply side. It is sectional drawing explaining a drilling process. It is process explanatory drawing. It is explanatory drawing of the unit according to station. It is a perspective view of a unit. It is a left view of the unit which fractured partially. It is a top view of a unit. It is a side view of a metal core and a punch. It is a front view of a metal core and a punch. It is explanatory drawing which shows the state which a workpiece | work hits a stripper. It is explanatory drawing according to station of the state in which a punch is driven into the thickness of a work cylinder part. It is a top view of a die block. It is sectional drawing of the periphery on the hole of a die block. It is sectional drawing of a workpiece | work. It is sectional drawing which illustrates the example of a form of a punch typically. It is sectional drawing of the workpiece | work with which the through-hole was drilled using the dent part. It is sectional drawing of the state which set the 1st punch in another example. It is sectional drawing of the state which driven the 1st punch into the surrounding wall of the workpiece | work. It is sectional drawing of the state which set the 2nd punch. It is sectional drawing of the state which struck the 2nd punch in the recessed part of the surrounding wall. It is sectional drawing of the state which set the 3rd punch. It is sectional drawing of the state which struck the 2nd punch in the through-hole of the surrounding wall. It is a top view which shows the exchange mechanism of a punch holder. It is a side view which shows the exchange mechanism of a punch holder. It is explanatory drawing explaining the conventional drilling apparatus.

Explanation of symbols

10, 10x work 12, 12x cylindrical part 15, 15x peripheral wall 15y concave part 15z convex part 17 concave part 17a peripheral edge 18 shearing 19 breakage 20, 20x die 24 discharge hole 30 punch 30a chamfered part 30x first punch 30y second punch 30z 3rd punch 31x 1st punch holder 31y 2nd punch holder 31z 3rd punch holder 32 Core metal 32x 1st metal core 32y 2nd metal core 32z 3rd metal core 40 Lifting block 40a Slide block 42 Holding hole 50 Pressurizing means 52 Pressurizing device 54 Elastic means 60 Suction means 62 Compressed air source 70, 70x Through hole 72 Punch holder feeding mechanism 75 Punch holder attaching / detaching mechanism 80, 80z Dregs 81 Feeder means

Claims (20)

It is a method of drilling a through-hole by press punching in the peripheral wall of the cylindrical part of a workpiece having at least a part of the cylindrical part,
The workpiece is adsorbed by a feeder means and positioned on the die while being slidably held in the punching direction, and a punch projecting shorter than the thickness of the peripheral wall is provided on a rod-shaped core metal held in a cantilever manner. It is in a state where it is inserted inside the cylindrical part,
By punching the punch into the peripheral wall from the inside of the cylindrical part by punching the punch in the direction close to the die through the cored bar, shearing and breaking are made, and a through hole is formed And
A method for drilling a through-hole in a work peripheral wall, wherein when the through-hole is drilled, the through-hole is opened by sucking and removing the punched-out scrap from the discharge hole of the die punched-out scrap. Prior to drilling the through hole, a crushing punch is punched into the peripheral wall from the outside of the cylindrical portion corresponding to the planned drilling position of the through hole, and the recess has a peripheral edge that is one size larger than the through hole. Form the
2. The workpiece according to claim 1, wherein when the through-hole is formed, the punch is driven into the peripheral wall from the inside of the cylindrical portion to cause shearing and breaking to reach a peripheral edge of the recessed portion. A method of drilling a through hole in a peripheral wall.   3. The method for drilling a through hole in a work peripheral wall according to claim 1, wherein when the punch and the die are relatively moved under pressure, pressure is applied with a spring force interposed therebetween. An apparatus for drilling a through-hole by press punching in a peripheral wall of the cylindrical part of a workpiece having at least a part of the cylindrical part,
A die which is one mold for processing the workpiece;
Feeder means for sucking the workpiece and supplying it to the die while holding it slidable in the punching direction;
A punch that is protruded shorter than the thickness of the peripheral wall on a bar-shaped metal core held in a cantilever manner, and is inserted into the cylindrical portion;
By punching the punch into the peripheral wall from the inside of the cylindrical part by punching the punch in the direction close to the die through the cored bar, shearing and breaking are made, and a through hole is formed A punching device for a through hole in a work peripheral wall.   The cored bar is formed to be narrower in the moving direction than the rear end side part so that the tip side where the punch protrudes can move in the pressurizing direction inside the cylindrical part for press punching, 5. A through-hole drilling device in a work peripheral wall according to claim 4, wherein R is taken at the step portion between the front end side and the rear end side of the cored bar. An apparatus for drilling a through-hole by press punching in a peripheral wall of the cylindrical part of a workpiece having at least a part of the cylindrical part,
A die which is one mold for processing the workpiece;
Feeder means for sucking the workpiece and supplying it to the die while holding it slidable in the punching direction;
A punch that is protruded shorter than the thickness of the peripheral wall on a bar-shaped metal core held in a cantilever manner, and is inserted into the cylindrical portion;
By moving the punch relatively close to the die through the core bar, the punch is driven from the inside of the cylindrical part into the peripheral wall of the workpiece, causing shearing and breaking, and making a through hole. Pressure means to be installed,
A punching device for a through hole in a work peripheral wall, wherein the end face of the punch is chamfered so as to follow the shape of the inner peripheral face of the cylindrical portion.   7. A suction means for sucking and removing a punched residue from a discharge hole of a punched die of a die so as to open the through hole when the through hole is formed. Drilling device for through-holes in the workpiece peripheral wall.   The through hole in the work peripheral wall according to claim 7, wherein the suction means is a negative pressure suction device that generates a negative pressure by a venturi effect by opening compressed air to a channel having a larger cross-sectional area. Drilling device.   The said pressurizing means is provided with an elastic means to pressurize by interposing a spring force when the punch and the die are relatively pressed and moved. Or the drilling device of the through-hole in the workpiece | work surrounding wall of 8.   A workpiece having at least a part of a cylindrical portion, wherein the through hole is opened in the peripheral wall of the cylindrical portion by the through-hole drilling device in the peripheral wall of the workpiece according to claim 4, 5, 6, 7, 8, or 9. Work characterized by that. It is a method of drilling a through-hole by press punching in the peripheral wall of the cylindrical part of a workpiece having at least a part of the cylindrical part,
While the concave portion to be a part of the through hole is positioned on the die, the workpiece formed by means other than the press on the outer peripheral portion of the peripheral wall corresponding to the planned drilling position of the through hole,
Projected on a bar-shaped cored bar held in a cantilever manner, with a punch formed on the periphery being slightly smaller than the recessed portion inserted into the cylindrical portion,
The punch is driven into the peripheral wall from the inside of the cylindrical part by shearing and breaking to reach the peripheral edge of the recessed part by relatively pressing and moving the punch through the cored bar in a direction close to the die. A method for drilling a through hole in a work peripheral wall, wherein the through hole is drilled.   12. The method for drilling a through hole in a work peripheral wall according to claim 11, wherein the means other than the press for forming the recessed portion on the outer peripheral portion of the peripheral wall is a cutting process, a molding process or an electric discharge process. It is a method of drilling a through-hole by press punching in the peripheral wall of the cylindrical part of a workpiece having at least a part of the cylindrical part,
The workpiece is positioned on the die, and a punch that protrudes shorter than the thickness of the peripheral wall is inserted into the rod-shaped metal core held in a cantilever manner, and is inserted into the cylindrical portion. The process of punching the punch into the peripheral wall from the inside of the cylindrical part and punching the through hole is divided into two stages by relatively pressing and moving the punch close to the die.
In the first stage, the first punch is driven into the peripheral wall to cause shearing, so that a concave portion is formed on the inner wall surface and a convex portion is formed on the outer wall surface,
In the second stage, the second punch, which is longer than the first punch and has a small diameter, is driven into the recess to finally cause breakage, thereby forming a through hole. A method for drilling a through hole in a workpiece peripheral wall.   As a third step following the two-step process of drilling the through hole, a third punch that is longer than the second punch and has a small diameter is formed from the inside of the tubular portion. 14. The method for drilling a through hole in a work peripheral wall according to claim 13, wherein the through hole is opened by driving into the through hole and removing the punched debris.   15. The method for drilling a through hole in a work peripheral wall according to claim 13 or 14, wherein the process in each step is performed using the same die. An apparatus for drilling a through-hole by press punching in a peripheral wall of the cylindrical part of a workpiece having at least a part of the cylindrical part,
A die which is one mold for processing the workpiece;
A rod-shaped metal core that is held in a cantilever manner is protruded to be shorter than the thickness of the peripheral wall, and is inserted into the cylindrical portion through the metal core and is relatively pressurized in a direction close to the die. A half-cut is performed so that a concave portion is formed on the inner wall surface and a convex portion is formed on the outer wall surface by being driven into the peripheral wall from the inside of the cylindrical portion by being moved and causing shearing. A first punch to perform,
A rod-shaped metal core that is held in a cantilever manner is projected to be shorter than the thickness of the peripheral wall and longer than the first punch and to have a small diameter, and to the inside of the tubular portion via the metal core. A through hole is formed by being inserted and moved in a direction close to the die so as to be driven into the concave portion from the inside of the cylindrical portion and finally causing breakage. A device for drilling a through hole in a work peripheral wall, comprising: a second punch.   A rod-shaped cored bar held in a cantilever manner is projected longer than the second punch and has a small diameter, and is inserted into the cylindrical part through the cored bar and close to the die. The third is opened from the inside of the cylindrical portion into the through hole provided by the second punch by being relatively pressurized and moved in the direction, and the through hole is opened by eliminating the punched debris. The punching device for a through hole in the work peripheral wall according to claim 16, wherein the punching hole is provided.   18. The work peripheral wall according to claim 16 or 17, wherein the die has one die while at least two punches are provided in order to use the first punch and the second punch as components. The through-hole drilling device in FIG. Each punch holder for holding the core metal in a state of protruding the end side provided with each punch,
Each of the punch holders is detachably held, and one slide block provided so as to be slidable back and forth in the press punching direction;
The work peripheral wall according to claim 18, further comprising: a pressure device that pressurizes the slide block to move the punch in a press punching direction via the punch holder and the cored bar. A through-hole drilling device. A punch that is sequentially provided to a predetermined position for attaching / detaching to / from the slide block, provided with a frame body portion that guides the punch holders so that the punch holders can be held in parallel and movable in an attaching / detaching direction with respect to the slide block. A feeding mechanism of the holder,
20. A through hole drilled in a work peripheral wall according to claim 19, further comprising a punch holder attaching / detaching mechanism for removably moving the punch holder sent to the predetermined position with respect to the slide block. apparatus.

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