JPS6039531A - Adhesion strength measuring device of plastic sheet - Google Patents

Abstract

PURPOSE:To measure adhesion strength of a plastic sheet by holding a test piece by a clip member from an edge line part to both side faces of a measuring base whose section is roughly triangular, and giving a constant load and an intermittent tensile force to one and the other, respectively. CONSTITUTION:A test piece A is placed on a measuring base 10 whose section is roughly triangular, so that its side seam part is positioned at an edge line part 11, and both the ends are fixed by pressure and held by clip members 20, 30. The piece of a prescribed weight is set in advance to a load giving means 50. When a flywheel 42 rotates by 180 deg. by starting a motor 41, the test piece A slides in the right side direction of the measuring base 10, and when it further rotates by 180 deg., the tensile force is released, and the test piece A slides in the left side direction by a weight 52a, etc. When this operation is repeated, the side seam part is peeled off and cut, therefore, the number of times of reciprocation of the test piece A of this time is counted by a proximity switch 60. In this regard, the surface temperature of the measuring base 10 is kept constant by a heater 12.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. Technical Field 1 The present invention relates to an apparatus for measuring the adhesive strength of plastic sheets whose ends are overlapped and melt-bonded.

[Prior art 1] In general, thermoplastic resin sheets such as polyethylene and polypropylene, and laminated sheets made by laminating these sheets, are melt-bonded by heater heating, high-frequency heating, ultrasonic heating, etc., and are used as packaging containers for toothpaste tubes and the like. There is.

In this case, the plastic sheet needs to be melt-bonded to a degree sufficient to withstand repeated loads, and it is also necessary to test the adhesive strength to control and confirm the finished state of the bonded portion.

By the way, the # of the plastic sheet and the wearing style are the first.
As shown in the figure, the bent ends (1a) and (1a) are butted and welded together, and the ends (1a) are welded as shown in fjS2.
There is one in which la) and la) are overlapped and welded (hereinafter referred to as side seam). And, in the conventionally well-known tensile tester, C) (1).

(1) simply applies a tensile force in the direction of the arrow, so in the case of the one in Figure 1, the tensile force acts as a peeling force on the adhesive part, but in the case of the seam, it is an effective peeling force. It does not work, and it is practically impossible to measure the adhesive strength.

For this reason, conventionally, the adhesive strength of side seams has been evaluated by applying a load in accordance with the actual usage conditions to a product that is manufactured as a container and filled with contents.

However, such an adhesive strength test is time-consuming and labor-intensive, the evaluation is subjective and intuitive, and the number of tests is small, making it unreliable.

[Object of the Invention 1] Therefore, an object of the present invention is to provide a measuring device that can easily and accurately measure the adhesive strength of plastic sheets melt-bonded at the side seams.

[Structure and Effects of the Invention 1 In order to achieve the above objects, the adhesive strength measuring device according to the present invention includes a measuring table having a substantially triangular cross section, and a test piece placed from the ridgeline portion of the measuring table to both sides thereof. a clip member that presses and holds one end of the test piece; an intermittent driving means that applies an intermittent tensile force to one end of the test piece via the clip member; another clip member that presses and holds the other end of the test piece; It is characterized by comprising a load applying means that always applies a constant load to the other end of the test piece via the clip member.

The pIS3 diagram shows the principle of this invention.
The side seam part of the test piece <A) made of a plastic sheet was placed on the cross-sectional path - the ridgeline part (11) of the triangular measuring table (10), both ends were crimped and held with clip members, and one end was connected to the intermittent drive means. constant intermittent tensile force (F
By adding a) to the other end, way) (52),
The test piece (A), to which a constant load is applied by a coil spring (55) v, is reciprocated on the measuring table (10). In this case, the side seam part of the test piece (A) is placed on the measuring table (10).
It moves back and forth while climbing over the ridgeline portion (11), and is in a state of being peeled off, so that it is relatively easier to peel off than simply applying a tensile force to both ends as in the conventional testing machine.

Therefore, by counting the number of reciprocating movements until the side seam portion of the test piece is cut, the adhesive strength can be measured based on this count. This measurement is
It is a relative value that varies depending on conditions such as the reciprocating stroke, the amount of load applied to the other end of the test piece, the angle of the measuring stand, the radius of its ridgeline, and the temperature of the measuring stand itself. However, by making measurements while keeping these various conditions constant, it is possible to obtain objective measurement values that can be fully utilized as comparative values.

[Example 1] In FIG. 4, the adhesive strength measuring device according to the present invention schematically includes a measuring table (1o) and a clip member (20).

(30), intermittent drive means (4o) and load applying means (5
0) and a counting proximity switch (6o).

The measurement stand (10) is a support (71) installed on the base (7o).
), it has a triangular cross section (isosceles), the angle of both sides is 60', and the ridgeline part (
) is set to 0.5 mm.

The reason why it is not used as a knife is because it requires a certain amount of slippage. Further, a Teflon tape is attached to the surface of this measuring table (1o). This is also to improve the sliding of the test piece (A). Furthermore, a heater (12) and a temperature measuring element (13) are installed inside the measuring table (10), and the temperature of the measuring table (1o) is monitored by the temperature measuring element (13), and the temperature of the measuring table (1o) is monitored. By controlling on/off, the surface temperature of the measuring table (1o) is kept constant. The purpose of heating the measuring table (10) in this way is to keep the temperature of the measuring table (10) constant, which is the measurement condition.
This is to heat the test piece (A) and promote peeling of the side seam portion.

The clip members (20) and (30) are generally known as charging clips, and are capable of crimping and gripping the end of the test piece (A) with the gripping claws (21) and (31).

By the way, rollers (22) and (32) are rotatably mounted on both sides of the clip members (20) and (3U).
By rolling the rollers (22) and (32) on the guide plates (15a) and (15b) attached to the top of the support column (71), I) the clip members (20) and (30) are moved in the vertical direction; Guide.

The intermittent drive means (40) consists of a seven-wheel drive wheel (42) fixed to the output shaft of a motor (41,) attached to the top of a mounting plate (U2) installed on the base (70). A wire (23) extending downwardly from the member (20)
) is fixed to an eccentric pin (43) fixed to the periphery of the flywheel (42). Therefore, the motor (4
1), the flywheel (42) rotates, and the clip member (20) reciprocates with a stroke equal to the eccentricity of the bottle (43) x 2.

The load applying means (50) includes various weights (52a), (521+), (52c), etc. that can be attached to and detached from the shaft 7) (51), and extends downward from the clip member (30). The lower end of the wire (33) is the wire 7) (51)
is connected to the top of the In addition, the lower part of the shaft 7) (51) is inserted into the thrust bearing (54) of the arm (53) attached to the takeaway 4 plate (73), and the weight (52a)
)... is guided in the vertical direction to prevent left and right wobbling.

In addition, each wire (23), (33) is located at the tip of the bracket (16), (16) attached to the middle part of the support column (71), but is inserted into the idle ring (17), (17). .

On the other hand, the counting proximity switch (60) is a rechargeable type consisting of a light emitting element and a light receiving element, and the sensor part (61) is installed on the mounting plate (73) so as to face the weight (52c), and its output is inputted to a counting means, a count display means, and a recording means (not shown).
)... The number of vertical movements is counted, displayed, and recorded.

In the above configuration, the test piece (A) is placed on the measuring table (10) so that the side seam portion is located at the ridge line portion (11), and both ends are attached to the clip member (20).

Crimp and grip at (30). (52a) . . . are set in advance with arbitrary weights.

Here, when the motor (41) is started, the flywheel (42) rotates 180'' from the position shown in the figure in the direction of the arrow (,), and the wire (23) and the chestnut knob member (20) move (way) (52a). ... is pulled in the direction of the arrow (F), and the test piece (A) slides toward the right side of the measuring table (10).The flywheel (42) further moves in the direction of the arrow (a). When rotated 180° to
2a) It slides toward the left side of the measuring table (10) under the load of... That is, the side seam part of the test piece (A) is moved to the measuring table (10) according to one rotation of the flywheel (42).
By climbing over the ridge line portion (11) and reciprocating once, and repeating this movement, the side seam portion will peel off and eventually be cut.

In addition, the number of reciprocations of the test piece (A) is (way) (52a).
The proximity switch (60) counts the number of up and down movements, and this count value is used to indicate the adhesive strength.

During this measurement, it goes without saying that the heater (12) is turned off and on to maintain the surface temperature of the measuring table (10) at a predetermined temperature.

Here, the measurement data obtained by the measuring device shown in FIG. 4 is shown in the table below.

In the above 1III constant data, the test piece number [11゜121 is a comparison when the weight of the weight (52a)... is changed, and as the weight increases, the load applied to the test piece increases and the measured value decreases. do. In addition, the test piece number [11,
[3] and [4] are comparisons when the temperature of the measuring table (10) is changed; as the temperature increases, peeling is promoted and the measured value decreases. Furthermore, the test piece number [1j.

I5] and [6] are comparisons when different types of plastic sheets are used. Grade A has weaker melt adhesive strength than Grades B and C, and Grade C has a lower melting temperature. Differences are observed in the measured values depending on the

In actual measurement, it is possible to set various conditions, but in general, if the measured value decreases, it is difficult to clearly confirm the differences between the test pieces, and if the measured value becomes too high, the measurement will take a long time. In short, it's not practical.

Note that the adhesive strength measuring device according to the present invention is not limited to the above-mentioned embodiments, and can be variously modified within the scope of the gist.

For example, the load applying means (S t)) is
2a)... Instead of using a coil spring (55) as shown in Fig. 3, it is less than 1°. This can be done by making the redundant position variable and adjusting the initial tension force.

It is also conceivable to use an electromagnetic slide as the intermittent drive means (40).

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing the form of adhesion of plastic sheets, FIG. 3 is a detailed explanatory view of the present invention, and FIG. 4 is a partial cross-sectional view showing one embodiment of the present invention. (1)...Plastic sheet, (A)...Test piece, (10)...Redundancy measuring stand, (11)...Ridge line portion, (
12)... Heater, (13)... Temperature measuring element, (20)
, (30)...Crimp part shrine, (40)...Intermittent drive means, (50)...Load a;! giving means, (60)
···Proximity switch. Patent applicant Sunstar Group Development Forest Company Agent
Patent attorney Aohaku Ao and 2 others

Claims (2)

[Claims] (1) A measuring table with a roughly triangular cross section, a clip member that crimply holds one end of the test piece placed from the ridgeline to both sides of the measuring stand, and an intermittent clip on one end of the test piece via this clip member. an intermittent driving means for applying a tensile force, another clip member for crimping and holding the other end of the test piece, and a constant load being constantly applied to the other end of the test piece through this clip member. 1. An apparatus for measuring adhesive strength of a plastic sheet, characterized in that it is equipped with a means for applying a load. (2) The apparatus for measuring adhesive strength of a plastic sheet as set forth in claim 1, wherein the measuring table has a built-in heater and a temperature measuring element.