JPH11291195A - Test piece punching method, device thereof, and punching cutter therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a test piece punching method, a device thereof, and a punching cutter therefor which can obtain an elongated-shaped flat test piece easily, promptly, and efficiently without changing material even if it is a thick sheet. SOLUTION: When a dumbbell test piece serving as an elongated-shaped flat test piece is punched by punching a press sheet P, a left slit L1 is cut in the press sheet P in a first lateral slitting process, and a right slit L2 is cut in a second lateral slitting process. Short side slits L3a, L3b are then cut in a first and second short side slitting processes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test for punching out a long flat test piece such as a tensile test piece or an impact test piece from a sheet material such as rubber, plastic, vinyl, polyethylene or paper. The present invention relates to a one-side punching method and apparatus, and a punching cutter used in this apparatus.

[0002]

2. Description of the Related Art Various tests, such as a tensile test and an impact test, are performed on each of the above materials based on JIS (Japanese Industrial Standards). ing. For example, when performing a tensile test on a plastic material, a test piece formed in a predetermined flat dumbbell shape is used, and when performing an impact test, a test piece formed in a predetermined prismatic shape is used. Recently, JIS and ISO (International Organization for Standardiza
JIS has been changed in order to match with). For example, in a tensile test of a thermoplastic material, the thickness of a dumbbell-shaped test piece was set to 2 mm in the old JIS, but was changed to a new JIS (JIS-713).
9-1996 standard), the thickness of the dumbbell-shaped test piece is changed to 4 mm.

A conventional test piece based on the old JIS has been formed by punching a sheet material having a predetermined thickness using a punch cutter having a thin blade. The blade in such a punching cutter is formed by forging, or as disclosed by the present applicant in Japanese Patent Publication No. 7-61639, a plurality of (for example, four front, rear, left, and right) blades are used. By combining them, a planar shape is formed so as to be integrally connected so as to have the same shape as the test piece. Then, each test piece was formed by a single punching operation by pressing the thus formed punching cutter against a sheet material using a press device.

[0004]

However, there is a problem that a test piece based on the new JIS cannot be formed by the same method as that for forming a test piece based on the old JIS as described above. That is, in the old JIS, since the thickness of the test piece was 2 mm, a high-density polyethylene material (HDPE) or a low-density polyethylene material (HDPE) was used with a cutter configured as described above using a blade having a thickness of about 0.3 mm. (LDPE) etc. could be easily and accurately punched. However, when trying to punch HDPE or LDPE with a thickness of 4 mm with the above-mentioned cutter, the material inside the blade is simultaneously compressed from the surroundings (front, rear, left and right) due to the spread of the cut edge of the material at the time of punching, and a large compression is applied to the test piece. Force acts. In particular, when the test piece is long, the two sides extending in the longitudinal direction are close to each other, so that the compressive force therebetween is particularly large.

When such a compressive force acts, a change in the material called "whitening" occurs, and the characteristics of the test material change. In addition, the stress acting on the blade is increased and the blade is easily spilled, so that a conventional blade having a thickness of about 0.3 mm cannot be completely punched. Therefore, if a thick blade that can be punched without spilling the blade is used, the spread of the cut edge is further increased, so that the material changes and the punching force (pressing force) is also required to be large. Also, when punching is performed with such a thick blade, the punched surface is inclined by 5 ° or more (when punching 4 mm, the position is shifted by about 0.5 mm), and the perpendicularity of the punched surface decreases.

For this reason, when the thickness is increased, it is conceivable to form a test piece by cutting instead of punching out the sheet material as described above. However, in the cutting process, there is a problem that it takes time to form a test piece, and there is also a problem that a material changes due to frictional heat at the time of cutting.

The present invention has been made in view of such a problem, and a long and flat plate-like test piece can be easily and efficiently obtained in a short time without causing a change in the material even for a thick sheet material. An object of the present invention is to provide a method and an apparatus for punching a test piece that can be obtained, and a punch cutter used in the apparatus.

In order to achieve such an object, a test piece punching method according to the present invention for punching a long flat test piece from a sheet material includes a first side cutting step (for example, in the embodiment). Step of making left cut L1 in press sheet P by first cut device 410 described above)
And a second side cutting step (for example, a step of making a right cut L2 in the press sheet P by the second cutting device 420 described in the embodiment), a first short side cutting step, and a second short side cutting step (for example, A step of forming the end face cuts L3a, L3b in the press sheet P by the third cutting device 430 described in the embodiment).

The first side cutting step is to make a cut to form one of the two sides extending in the longitudinal direction of the plate-shaped test piece, and the second side cutting is performed. The process involves making a cut to form the other of the two longitudinally extending sides. Further, the first short side notch step is to make a cut for forming one of the two short sides of the plate-shaped test piece, and the second short side cut step is two cuts. A cut is made to form the other of the short sides.

[0010] Then, after forming one side extending in one longitudinal direction by the first side cutting step, a side extending in the other longitudinal direction is formed by the second side cutting step. . According to such a test piece punching method, a long flat test piece can be punched from the sheet material by cutting the sheet material in each step, but the test piece extends in two longitudinal directions. Two cuts for forming the side are not made at the same time, and one of the cuts is made first. That is, when the cut is made, the cut is expanded. However, when two cuts are made at the same time at a small interval, a large compressive force (stress) is generated at the portion between the cuts, and the cut that penetrates the sheet material is made. May not be possible, or the blade for making the cut may be spilled. However, if the cuts for forming the sides extending in the longitudinal direction are formed one by one in order as described above, since a large stress does not occur between the cuts, it is simple and,
The incision can be made with a small force.

Note that the first short side cutting step and the second short side cutting step for making a cut for forming the short side are performed after the first side side cutting step and the second side side cutting step. Alternatively, it may be performed after the first side edge cutting step or before the first side edge cutting step. Further, since the cut for forming the short side is formed at a position separated by the length of the side, even if two cuts are formed at the same time, the large stress as described above does not occur.
Therefore, the first short side cutting step and the second short side cutting step may be performed simultaneously to make cuts for forming short sides at the same time.

In the test piece punching method according to the present invention, the first side cutting step is repeated to form a plurality of sides extending in one longitudinal direction in parallel, and then the second side cutting step is repeated. By doing so, a plurality of sides extending in the longitudinal direction are formed in parallel with the sides extending in one longitudinal direction. Then, it is preferable that the first short side cutting step and the second short side cutting step are performed at the same time so that cuts forming two short sides of a plurality of flat plate test pieces are formed at the same time. By using such a method, a plurality of test pieces can be punched out of one sheet material, but since a plurality of cuts are not simultaneously made in close positions, the test pieces can be efficiently cut. Punching can be performed.

[0013] A test piece punching apparatus for punching a long flat test piece from a sheet material according to the present invention for achieving the above object is a base (for example, the main body 1 according to the embodiment). ) And sheet material holding means for holding the sheet material (for example, the moving table 3 described in the embodiment).
And a first side cutting unit (for example, the first cutting device 410 according to the embodiment), and a second side cutting unit (for example, the second cutting device 420 according to the embodiment).
And short side notching means (for example, the third
The cutting device 430) and a moving unit (for example, the table moving device 2 described in the embodiment).

The first side notch means is a notch for forming any one of two longitudinally extending sides of the flat test piece in the sheet material held by the sheet material holding means. The second side cut means cuts the sheet material held by the sheet material holding means to form the other side. The short side notch means cuts the sheet material held by the sheet material holding means to form two short sides of the flat test piece and punches the test piece from the sheet material. .

According to the test piece punching apparatus constructed as described above, the sheet material is cut in accordance with the above-described test piece punching method, so that when the cut test piece is cut, a large stress is applied to the sheet material. It is possible to obtain a test piece which does not change the material and does not cause a dimensional change.

In the test piece punching apparatus thus configured, a plurality of cutter members (not shown) are used as punching cutters for cutting a sheet material to form two long sides and two short sides. For example, it is preferable to use a punching cutter including the first, second, and third punching cutters C1, C2, and C3 described in the embodiment. These cutter members are formed in such a manner that the outer surface has the same shape as each of the two long sides extending in the longitudinal direction and the two short sides. A holding plate having a side surface of a shape almost in contact with the outer surface of the template,
A flexible thin blade having the same length as the developed length of the outer surface of the base template. Then, sandwich the thin blade and press the side of the holding plate against the corresponding outer surface of the base template to attach the thin blade and the holding plate to the outer surface of the base template. The cutting edge of the blade is configured to protrude below the base template and the holding plate.

With such a configuration, even if the blade for making the cut is formed thin, the cut is formed in a shape corresponding to the shape of each side and short side extending in the longitudinal direction of the required test piece. The blade for inserting can be easily formed. In addition, since the blade for making the cut can be made thinner, the stress acting on the sheet material at the time of making the cut can be made smaller, so that a test piece with less change in material and less deformation can be obtained. .

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, referring to FIG. 2 and FIG. 3, a plastic test piece punching apparatus S which is an example of a test piece punching apparatus according to the present invention configured to be capable of punching a test piece by the test piece punching method according to the present invention. explain. The plastic test piece punching apparatus S includes a main body 1, a table moving device 2 mounted on the main body 1, and a moving table movably mounted on the table moving device 2 and capable of holding a sheet material. 3 and a punching device 4 which is located above the table moving device 2 and is attached to the main body 1. The sheet material is a polyethylene sheet material as shown in FIG. 1 (hereinafter referred to as "press sheet"). 1.) P is punched out to form a test piece having a desired shape (dumbbell shape in FIG. 1).

The main body 1 includes a gantry 11 formed in a rectangular box shape.
And a top plate 12 mounted on the gantry 11. The table moving device 2 and the punching device 4 are mounted on the top plate 12. The gantry 11 is
It has an electric control unit 13 for setting and integrating the number of punched press sheets P and the like, as will be described in detail later, and an air pressure control unit 14 for controlling the driving air pressure and the like of a punching air cylinder, also described in detail later. It is configured.

Next, the table moving device 2 and the moving table 3 will be described with reference to FIGS. The table moving device 2 includes two sliders 21 and 21 extending in the longitudinal direction (left-right direction) of the main body 1 and arranged in parallel.
, A ball screw 22 disposed between the sliders 21 and 21, and a table moving motor 23 for rotating the ball screw 22. Slider 2
1 includes a fixed member 21a and a moving member 21b, and the moving member 21b is configured to be movable with respect to the fixed member 21a.

The moving table 3 includes a table body 31 and
An upper and lower clamp device 32, a stopper 33 and a lateral clamp device 34 disposed on the upper surface of the table main body 31,
And a nut 35 disposed on the lower surface of the table body 31. The moving member 21b is attached to the back surface of the table main body 31, and the ball screw 22 is attached to the nut 35.
Is screwed. Therefore, the table moving motor 23
By rotating the ball screw 22 by performing the rotational drive control described above, the work moving table 3 can be moved with respect to the fixed member 21a. In the following description, the moving direction of the work moving table 3 is referred to as a left-right direction (lateral direction), and the left-right direction in FIGS.

The upper and lower clamp devices 32 and 32 are attached to the front and rear of the table main body 31, respectively. The upper and lower clamp members 32a are provided to be vertically movable with respect to the table main body 31, and the upper and lower clamp cylinders 32 are provided.
b, the upper and lower clamp members 32a are moved by controlling the expansion and contraction operation of the upper and lower clamp cylinders 32b.
It can be moved up and down between the release position and the clamp position. The horizontal clamp device 34 is attached to a rear portion of the table main body 31 and includes a horizontal clamp member 34a movably provided in the horizontal direction with respect to the table main body 31 and a horizontal clamp cylinder 34b. By controlling the expansion / contraction operation of the clamping cylinder 34b, the horizontal clamping member 34a
Can be moved in the front-rear direction between the release position and the clamp position.

The table moving device 2 thus configured
And the moving table 3, each of the clamping devices 32,
After the press sheet P is placed on the table body 31 in a state in which the clamp device 32 has been moved to the release position,
34 is moved to the clamp position. Thus, the press sheet P is pressed against the table body 31 and also against the stopper 33. Thus, the press sheet P is held on the moving table 3 with the front, rear, left, and right positions fixed.

Incidentally, such a clamping operation is performed by the main body 1.
The operation is performed by operating the clamp switch 131a provided in the control unit. The adjustment of the clamping force of the vertical clamping cylinder 32b is performed by adjusting the supply air pressure by the vertical clamping regulator 141a, and the adjustment of the clamping force of the horizontal clamping cylinder 34b is performed by adjusting the supply air pressure by the horizontal clamping regulator 141b. Note that these adjusted air pressures are measured by the pressure gauges 142a and 142b.
Can be grasped.

Such holding of the press sheet P on the moving table 3 is performed at a start position where the work moving table 3 is moved rightward as shown by a solid line in FIG. If the operation control of the table moving motor 23 is performed in a state where the press sheet P is held at the start position, the moving table 3 can be moved to the left as shown by a chain line in FIG. P can be moved below the punching device 4.

Next, the punching device 4 for punching a test piece will be described. The punching device 4 includes a column 41 attached to the main body 1 and a cylinder mounting plate 42 supported by the column 41. The cylinder mounting plate 42 has a first cutting device 410 and a second cutting device. A device 420 and a third cutting device 430 are provided. Each cutting device 410, 420, 430
Lifting rods 411, 421, 431 arranged to be able to move up and down with respect to the cylinder mounting plate 42;
Cutter mounting plate 412 attached to the lower end of 1 etc.
422, 432 and cutter mounting members 413, 423, 433 mounted on the cutter mounting plate 412 and the like.
And punching air cylinders 414, 424, and 434 attached to the upper surface of the cylinder attachment plate 42. The telescopic rod such as the punching air cylinder 414 is attached to the cutter mounting plate 412 and the like, and the cutter mounting plate 412 and the like move up and down with respect to the cylinder mounting plate 42 by performing the expanding and contracting operation of the punching air cylinder 412 and the like. It is supposed to do.

Then, a first punching cutter C1 is mounted on the first cutter mounting member 413, a second punching cutter C2 is mounted on the second cutter mounting member 423, and a third punching cutter C2 is mounted on the third cutter mounting member 433. The cutter C3 is attached. For this reason, by performing the expansion / contraction operation control of each punching air cylinder 414 and the like, the lifting / lowering operation of each punching cutter C1, C2, C3 from the position shown by the solid line to the position shown by the chain line in FIG. 4 can be performed. It has become.

Each of the punching cutters C1, C2, C3
The press sheet P is provided so that a cut can be made in the lowered position. In the plastic test piece punching apparatus S, one test piece is not formed by one lifting and lowering operation (one shot) of one punch cutter, but two or three pieces each having a different shape are used. Punching cutter C1, C2, C3
Are operated one by one to punch out one test piece.

That is, for example, as shown in FIG. 1, five dumbbell-shaped test pieces DP, DP are formed from one press sheet P.
Is punched, first, the press sheet P set at the start position is moved below the first punching cutter C1, and the first pressed sheet P is moved to the left by a predetermined pitch P1.
FIG. 6 (A) is obtained by making five shots of the punching cutter C1.
As shown in Fig. 5, only the left cut L1 in the dumbbell-shaped test piece DP is made at five places.

Thereafter, the press sheet P is moved below the second punching cutter C2, and similarly, the second punching cutter C2 is moved forward by a predetermined pitch P2.
The shot is made, and five cuts L2 on the right side of the dumbbell-shaped test piece DP are made as shown in FIG. Thereafter, the press sheet P is further cut into a third punch C3.
, And two notches L3a and L3b of the end face of the dumbbell-shaped test piece DP are simultaneously inserted in the upper and lower portions as shown in FIG. Thereby, five dumbbell-shaped test pieces DP, DP... Can be punched from one press sheet P.

Here, the configuration of the punching cutter will be described with reference to FIGS. 7 to 9 taking the first punching cutter C1 as an example. The first punching cutter C1 has a mounting portion C1.
1, a base template C13 and a holding plate C14 attached to the lower end of the attachment portion C11,
3 and a first blade C10 sandwiched by C14. The outer side surface 13a of the base template C13 and the side surface 14a of the holding plate C14 are formed so as to match the shape (L1) of the side extending in the longitudinal direction on the left side of the dumbbell-shaped test piece DP shown in FIG. In addition, the first blade 10 is a thin blade having flexibility and can be deformed in the longitudinal direction.

Therefore, the side surface C13 of both plates C13 and C14
a, C14a, the first blade 10 is held between the two plates C1 by a plurality of bolts C19a and nuts C19b.
3, if C14 is tightened, the first blade 10 can be
Since the first blade 10 can be deformed along the shape of C14a, the first blade 10 can be held in a state where the first blade 10 matches the shape (L1) of the side extending in the longitudinal direction on the left side of the dumbbell-shaped test piece DP.

Further, in the first punching cutter C1, four through-holes C12a vertically penetrating the mounting portion C11 and the respective plates C13 and C14 are formed, and the lower end of the through-hole C12a has a knockout plate. C15, C1
The stud C17 joined to 6 is loosely inserted from below.
A nut C17a is screwed onto the upper end of the stud C17, whereby the knockout plates C15 and C16 are vertically movably mounted to the mounting portion C11 and the respective plates C13 and C14.

Each of the plates C13 and C14 is further provided with two spring insertion holes C12b, and a knockout spring C18 is inserted into the spring insertion holes C12b before the knockout plates C15 and C16 are attached. Is done. For this reason, the knockout plate 11 is pushed downward by the knockout spring 13 as shown in FIG.
The nut C17a at the upper end of 7 is held in a state in which the nut C17a is in contact with the upper surface C11a of the portion protruding left and right in the mounting portion C11.

The first punching cutter C1 configured as described above is mounted on the first cutter mounting member 413. The first punching cutter C1 may be used for changing the shape of a test piece to be formed as described later in detail. When exchanging the blade 10 or the like, it is necessary to remove the first punching cutter C1. Therefore, the first punching cutter C1 is configured to be detachable from the first cutter mounting member 413. The first cutter mounting portion 413 has a first punching cutter receiving groove 4.
The first punching cutter C1 is attached to the first cutter mounting member 413 by inserting the insertion portion C11b formed on the upper portion of the first punching cutter C1 into the first punching cutter receiving groove 413a. be able to.

A positioning groove C1 is provided on the side surface of the insertion portion C11b.
1c is formed, and by fixing the fixing screw 413c in the state of being inserted as described above, positioning in the front-rear direction (left-right direction in FIG. 7) can be performed. In the state of being inserted and held in this manner, the fixing plates 413b, 4
13b, the first cutter mounting member 413
, The first punching cutter C1 can be firmly fixed. In the first punching cutter C1, handles H, H for facilitating such attachment and detachment are attached.

Next, the second punching cutter C2 will be described with reference to FIG. As described above, the second punching cutter C2 is for making the right cut L2 in the dumbbell-shaped test piece DP. However, since the dumbbell-shaped test piece DP is symmetrical in the longitudinal direction, the second punching cutter C2 is formed. Is formed in a shape symmetrical with the first punching cutter C1 (so-called difference). That is, the second punching cutter C2 also includes the mounting portion C21,
Base template C attached to the lower end of this attachment portion C21
23 and a holding plate C24, and both plates C23 and C2.
4 and a knockout plate C25, C26.

The shape viewed from the same direction as the direction shown in FIG. 7B is such that the direction in which the second blade 20 is curved as shown in FIG. 10 is the direction in which the first blade 10 is curved. It is formed to be opposite to the direction. The mechanism for moving the knockout plates C25 and C26 in the vertical direction in the second punching cutter C2 is the same as the mechanism for moving the knockout plates C15 and C16 in the vertical direction in the first punching cutter C1. Is omitted.

Next, with reference to FIG. 11, a description will be given of the third punching cutter C3 for making cuts for forming the upper and lower short sides (end faces) L3a and L3b in FIG. The third punching cutter C3 includes an attachment portion C31 and a base template C3 attached to a lower end of the attachment portion C31.
3, a first holding plate C34 and a second holding plate C35,
It has two third blades C30a and C30b sandwiched between these plates C33, C34 and C35. The configuration of the mounting portion C31 is the same as the configuration of each of the mounting portions C11 and C21 described above, and thus detailed description thereof will be omitted.

The two third blades C30a and C30b are formed in the shape of a straight thin blade and are located on the left and right end surfaces of the base template C33 mounted at the center of the mounting portion C31, and the first holding plate C34 and the second pressing blade C30. The holding plate C35 is disposed in parallel along the left and right outer surfaces of the base template C33 by screwing. Third in the base template C33
Inside the blades C30a and C30b, a knockout plate C36 which is supported by a stud C37 in the same manner as described above so as to be movable in the vertical direction and is constantly urged downward by a knockout spring C38 is attached.

Each of the punching cutters C1, C2, and C3 thus configured is connected to each of the cutter mounting members 413 and 42.
3,433 attached to each cutting device 410,4
20 and 430, each punching air cylinder 41
The press sheet P is punched by the operation of 4,424,434. Here, the operation control of each cutting device 410 and the like (each punching cylinder 414 and the like) is performed by a controller (sequencer) 131 b provided in the main body 1. The time is set by the shot number setting device 131
It can be set individually by c and the punching time setting device 131d. The punching force of each punching air cylinder 414 and the like is adjusted by adjusting the supply air pressure by the punching regulators 141c, 141d, and 141e, and these adjusted air pressures can be grasped by the pressure gauges 142c, 142d, and 142e. it can.

In the punching device 4 configured as described above, the cutting edges of the blades C10 and the like cut into the press sheet P by extending the punching air cylinders 414 and the like. At this time, knockout plate C
15 and the like can be moved up and down and are pushed upward from the cutting edge. However, when the punching cutter C1 or the like is lifted, the knockout spring C18 or the like pushes the knockout plate C15 or the like downward and cuts in with it. The test piece is discharged. In addition, each blade C10
And so on, each holding plate C13,
Although the amount of protrusion from C14 is large, since an underlay plate (not shown) made of resin is provided below the press sheet P, each blade C10 and the like are directly connected to the table body 31.
It is possible to reliably make a cut in the press sheet P without abutting the sheet.

With this configuration, when punching out the dumbbell-shaped test piece DP, the left and right sides extending in the longitudinal direction are cut with time, and then the upper and lower short sides (end faces) are cut. Therefore, a compressive force at the time of cutting simultaneously does not act from the outer periphery of the test piece. That is,
When the dumbbell-shaped test piece DP is punched from the press sheet P, a plurality of cuts are made using a thin plate-shaped blade. However, when the interval between the cuts is narrow such as the left cut L1 and the right cut L2, the cut is made. Are inserted one by one, so that no large stress is generated between the cuts. Also, when the interval between both cuts is wide as in the end face cuts L3a and L3b, the force when making one cut does not affect when making the other cut, so as described above. A cut can be made at the same time. Therefore, even if the sheet material is thick, the dumbbell-shaped test piece DP can be easily and efficiently punched out in a short time without any change in the material.

Next, a prismatic test piece S as shown in FIG.
The case where P is punched from the press sheet P will be described. In the case of such a prismatic test piece SP, since the cuts L4 and L4 for forming the longitudinal sides of the test piece are straight lines, the punching cutter for making cuts on the left and right sides is, As shown in FIG.
0 is a linearly formed side-side punching cutter C4
May be used. Then, the side punching cutter C4 is attached to the first cutting device 410, and the press sheet P held on the work moving table 3 using the stopper 33 and the lateral clamping devices 34a and 34b at a predetermined pitch as described above. By performing the punching operation a plurality of times (six times in FIG. 12) while feeding, first, the cuts L4 and L for forming the side extending in the longitudinal direction are formed.
Insert 4.

Next, as shown in FIG.
The short side punching cutter C5 provided with the two straight blades C50a, C50b, C50c is inserted into the second cutting device 4.
20, and cuts L5a, L5b, L5c for forming the short side (end face) of the prismatic test piece SP using the second cutting device 420. The short side cut by the short side punching cutter C5 is performed in one shot.

Even in the case of such a configuration, when the prismatic test piece SP is punched in the same manner as described above, a compressive force does not act simultaneously from the outer periphery of the test piece.
Even for thick sheet materials, there is no change in material,
Easily and efficiently form test specimens in a short time

Further, in the plastic test piece punching apparatus S, by replacing the punching cutter, a dumbbell-shaped tensile test piece DP2 as shown in FIG.
Also, the formation of a plate-like Olsen stiffness test piece SP2 as shown in FIG. 16 can be easily performed. In addition,
When the dumbbell-shaped tensile test piece DP2 is punched, the first cut device 410 cuts the left cut L1 similarly to the case where the dumbbell-shaped test piece DP is punched.
', And the right cut L2' is made by the second cutting device 420, and then the cuts L3a and L3b forming short sides are made by the third cut device 430. When the Olsen stiffness test piece SP2 is punched, the cuts L4 ′ and L4 that form the left and right sides extending in the longitudinal direction by the first cutting device 410, as in the case of punching the prismatic test piece SP. ', The cuts L5a' and L5b 'for forming the short side are made by the second cutting device 420.

[0048]

Preferred embodiments of the present invention will be described below with reference to the drawings. First, from a press sheet (HDPE or LDPE) P having a thickness of 4 mm, a width W of 200 mm and a length L of 200 mm, a length La of 17 mm is obtained.
The case of punching out five 0 mm dumbbell-shaped test pieces DP will be described. When performing such punching, first, the respective cutters C1, C2, and C3 are set in the respective cutting devices 410, 420, and 430. Next, on the table body 31 of the work moving table 3,
Underlay plate made of polypropylene 2 mm thick (not shown)
After the press sheet P is placed thereon, the clamp switch 131a is operated to cause the work moving table 3 to hold the press sheet P. Note that such holding of the press sheet P is performed in a state where the work moving table 3 is located at the start position.

When the press sheet P is held, the start switch 131e is operated to operate the work moving table 3.
Is moved to a first cutting position below the punching device 4 and a cut is made by the first cutting device 410. The first moving position refers to a moving position of the work moving table 3 to the left where the left cut L1 is formed at a position W1 away from the left end Pa of the press sheet P,
In this embodiment, it is 20 mm. Then, when the cutting at the first moving position is completed, the punching by the first cutting device 410 is repeatedly performed while moving the work moving table 3 at a predetermined pitch P1, thereby forming five left cuts L1 (FIG. 6 ( A). In this embodiment, P1 is 30 mm, and W1 and P1 are predetermined by the controller 131b.

After the formation of the left cut L1 is completed in this way, the work moving table 3 is moved to the second punching position, and the second cut device 420 makes a cut. The second moving position refers to a moving position of the work moving table 3 to the left where the right cut L2 is formed at a position separated by W2 from the left end Pa of the press sheet P. In the present embodiment, it is 40 mm. is there. Then, when the punching at the second movement position is completed, the workpiece movement table 3 is moved at a predetermined pitch P1 while the second movement is performed.
The cutting device 420 makes repeated cuts to make five right lines L2 (the state shown in FIG. 6B). When the right cut L2 has been cut in this way, the distance W3 from the rightmost cut L2 at the rightmost end to the right end Pb of the press sheet P is 40 mm.

When the left cut L1 and the right cut L2 are made in this manner, since the cut is slightly widened in the left-right direction as described above, the press sheet P slightly expands in the left-right direction. Is
Since the press sheet P is always pressed against the left stopper 33 by the urging force of the horizontal clamping cylinder 34b, the width dimension W of the press sheet P does not change, and the cuts L1, L2 can be inserted.

When the right cut L2 is completed, the work moving table 3 is moved to the third punching position and
A cut is made by the cutting device 430, and a dumbbell-shaped test piece DP is punched out. Note that the third movement position is substantially equal to the center of the width dimension W4 in the third punching cutter C3 and the center of the third left and right cuts L1 and L2 (a position separated by W5 from the left end Pa of the distance press sheet P). It is a matching position. In this embodiment,
W4 is 150 mm. Also, two third blades C30
Since a and C30b are disposed apart from each other by the length La of the test piece DP to be formed, the dumbbell-shaped test piece DP is formed at the time when the cutting by the third cutting device 430 is completed.
Can be cut entirely. In this embodiment, since a dumbbell-shaped test piece DP having a length of 170 mm is formed, La is also set to 170 mm.

In this embodiment, each blade C10,
The thickness t of C20 and C30 is formed to 0.3 mm, and the height is formed to 20 mm. The air cylinders 414, 424, and 434 for punching have a ram diameter of one.
80 mm and 150 mm stroke are used,
It is operated by compressed air with an air pressure of 6.5 kg / cm ² . The punching time is adjusted in the range of 0.12 to 3 seconds according to the material and thickness of the press sheet P.

In this way, each cutting device 410,
After the cutting by 420 and 430 is completed, the operation of the table moving motor 23 is controlled by the controller 131b, and the work moving table 3 is returned to the start position. Therefore, in this state, if the clamp switch 131a is operated again to release the clamp, the press sheet P from which the five dumbbell-shaped test pieces DP are punched out is pressed.
Can be taken out.

According to the plastic test piece punching apparatus S configured as described above, one press sheet P to 5
The time required to take out the dumbbell-shaped test pieces DP (time from the start position to the return to the start position) was 50 to 60 seconds. The cutting accuracy (parallelism) of the left and right cuts L1 and L2 is 10 ± 0.0.
Since the standard deviation between the upper surface and the lower surface of the cut surface was 0.015 to 0.020 mm, the squareness was also good. No whitening occurred, and the cut surface roughness was extremely good. Further, since the stress acting on each blade C10 at the time of cutting is about 1/3 of that at the time of punching the entire circumference at the same time, the blade does not spill and does not need to be replaced.
６００600 test pieces could be punched.

In the above-described embodiment, the case where the test piece is punched out by using the 200 mm square press sheet P has been described.
In, it is also possible to punch a test piece using a 250 mm square press sheet P. Note that 250
When the press sheet P having a square of mm is used, each of the clamping devices 32 and 34 is replaced with a clamp formed in accordance with the press sheet P having a square of 250 mm.

Further, a plastic test piece punching device S
In order to ensure the safety of the punching device and the breakage of the punching device during operation, it is preferable to provide a cover 51 on the upper part of the main body 1 so as to cover the punching device 4.
Further, in order to prevent dust from entering the slider 21 and the ball screw 22 in the table moving device 2, it is preferable to provide a bellows-like cover 52 on the table moving device 2.

[0058]

As described above, according to the test piece punching method of the present invention, the two sides extending in the longitudinal direction of the long plate-like test piece are cut by separate processes. Because it is formed, even in the form of a specimen that must be cut in close proximity,
Since no large stress is generated between the cuts, the test piece can be easily and reliably punched with a small force even with a thick sheet material.

In the test piece punching method according to the present invention, the first side cutting step is repeated to form a plurality of sides extending in one longitudinal direction in parallel, and then the second side cutting step is repeated. By doing so, a plurality of sides extending in the longitudinal direction are formed in parallel with the sides extending in one longitudinal direction. Then, it is preferable that the first short side cutting step and the second short side cutting step are performed at the same time so that cuts forming two short sides of a plurality of flat plate test pieces are formed at the same time. By using such a method, it is possible to efficiently punch a plurality of test pieces from one sheet material.

Further, a test piece punching apparatus for punching out a long flat test piece from a sheet material according to the present invention comprises:
Cut into the sheet material held by the sheet material holding means by the first side notch means to form any one of the two sides extending in the longitudinal direction of the flat test piece, A notch for forming the other side is formed in the sheet material held by the sheet material holding means by the two side notch means, and a flat sheet test is performed on the sheet material held by the sheet material holding means by the short side notch means. A test piece is punched out of a sheet material by making a cut to form two short sides of the piece. Accordingly, the sheet material is cut out based on the above-described test piece punching method, and the test piece is punched out. Therefore, a test piece that does not cause a change in material or a dimensional change can be easily obtained.

In the test piece punching apparatus configured as described above, a plurality of cutter members are used as a punching cutter for cutting a sheet material to form two long sides and two short sides. It is preferable to use a punching cutter. Each cutter member is configured so that the thin blade is sandwiched between the base template and the holding plate such that the blade edge of the thin blade protrudes below the base template and the holding plate. With such a configuration, the blade for making the cut can be formed thin, so that the stress acting on the sheet material at the time of making the cut can be reduced, and there is less change in the material and deformation. A test strip can be obtained. Further, since the replacement of the thin blade is easy, a test piece can be obtained at low cost.

[Brief description of the drawings]

FIG. 1 is a plan view showing a dumbbell-shaped test piece formed by a plastic test piece punching apparatus which is an example of a test piece punching apparatus according to the present invention.

FIG. 2 is a front view showing the plastic test piece punching apparatus.

FIG. 3 is a side view of the plastic test piece punching apparatus, and is a view as viewed in the direction of the arrow III in FIG.

FIG. 4 is a partially enlarged view showing a punching device portion of the plastic test piece punching device.

FIG. 5 is a side view of the punching device and is a view as seen from the arrow V in FIG. 4;

FIG. 6 is a plan view showing cuts of the dumbbell-shaped test piece over time, wherein (A) shows a state where a left cut is made, and (B) shows a state where a right cut is also made.
Shown in

7A is a side view of a first punching cutter in the punching device, and FIG. 7B is a view taken in the direction of arrow B in FIG.

FIG. 8 is a sectional view taken along the line VIII-VIII of FIG. 7A of the first punching cutter.

FIG. 9 shows the IX-I in FIG. 8 of the first punching cutter.
It is X sectional drawing.

FIG. 10 is a bottom view of a second punching cutter in the punching device.

11A is a side view of a third punching cutter in the punching device, and FIG. 11B is a view taken in the direction of arrow B in FIG.

FIG. 12 is a plan view showing a prismatic test piece formed by the plastic test piece punching apparatus.

FIG. 13 is a bottom view showing a side-side punching cutter for forming the prismatic test piece.

14A is a side view of a short-side punching cutter for forming the prismatic test piece, and FIG. 14B is a view taken in the direction of arrow B in FIG.

FIG. 15 is a plan view showing test pieces of different shapes punched by the plastic test piece punching apparatus.

FIG. 16 is a plan view showing test pieces of different shapes punched by the plastic test piece punching apparatus.

[Explanation of symbols]

 Reference Signs List 1 main body 2 table moving device 3 work moving table 4 punching device C1 to C5 punching cutter C10, C20, C30 blade S plastic test piece punching device P press sheet L1 to L5 cut

Claims (4)

[Claims] 1. A test piece punching method for punching a long plate-like test piece from a sheet material, wherein the plate-like test piece has one of two longitudinally extending sides. A first side edge cutting step of making a cut to form a side, a second side side cutting step of making a cut to form the other side of the two sides extending in the longitudinal direction, the plate-shaped test piece A first short side cutting step of forming a cut forming one of the two short sides, and a second short side forming a cut forming the other short side of the two short sides. After forming a side extending in one of the longitudinal directions by the first side cutting step, forming the side extending in the other longitudinal direction by the second side cutting step. Specimen punching method which is characterized in that formed. 2. The method according to claim 1, wherein the first side cutting step is repeatedly performed to form a plurality of side sides extending in the one longitudinal direction in parallel, and then the second side cutting step is repeatedly performed in the one longitudinal direction. A plurality of side sides extending in the other longitudinal direction are formed in parallel with the extending side sides, and the first short side cutting step and the second short side cutting step are simultaneously performed to perform the flat plate test for a plurality of sides. The method for punching a test piece according to claim 1, wherein cuts forming the short sides of the two sides of the piece are made at the same time. 3. A test piece punching apparatus for punching a long flat test piece from a sheet material, comprising: a base; sheet material holding means for holding the sheet material; A first side notch means for making a cut in the sheet material held by the sheet material holding means to form one of the two sides extending in the longitudinal direction of the flat test piece; A second side cut means attached to the base and making a cut forming the other side of the two sides in the sheet material held by the sheet material holding means; A short side for cutting the test piece from the sheet material by making a cut in the sheet material held by the sheet material holding means so as to form two short sides of the flat test piece. At a position where it is attached to the base and is capable of forming the other side by the second long side notch after the formation of the one side by the first long side notch. The sheet material holding means is moved, and the sheet material holding means is placed at a position where the two short sides can be formed by the short side forming means after the other long side is formed by the second long side forming means. And a moving means for moving the test piece. 4. A punch cutter comprising a plurality of cutter members that cut into the sheet material to form the two longitudinal sides and the two short sides, wherein each of the cutter members includes: A base template having a predetermined thickness formed so that the shape of the outer side surface is the same as each of the two sides extending in the longitudinal direction and the two short sides; and an outer surface of the base template. A holding plate having a side surface of a shape that is almost in close contact with a flexible thin blade having the same length as the developed length of the outer surface of the base template. And pressing the side surface of the holding plate against the corresponding outer surface of the base template so that the thin blade and the holding plate are attached to the outer surface of the base template. Front edge Punching cutter, characterized by being configured so as to protrude from the lower base type plate and the pressing plate.