DE102004010473B3 - Test device for workpiece covered in flock material uses air ionizer and rapping mechanism which dislodges flock from workpiece so that it falls into weighing receptacle - Google Patents

Abstract

The test device has a base frame (1) holding a support frame (2) with vibration dampers (3). A table (5) with a high-frequency vibrator (4) is supported on top of the frame. A pneumatic actuator (10) moves a swinging arm (8) with a weight (9) which raps against a projection on the frame. A workpiece (7) covered in flock material (12) is fastened to the vibrating table. An air ionizer (13) produces a stream of ionized air (14) which dislodges the flock from the workpiece so that it falls into a weighing receptacle (11).

Description

The The invention relates to a test method and a device for determining the triggerable flock amount of flocked Components.

From the GB 2 371 566 A is a carding machine for textile fibers is known in which are arranged below the drum between customers and lickers cover, between which at least one opening is present, which in turn is associated with a suction chamber. To reduce the short fiber content short fibers are sucked through the at least one opening. Also the GB 2 368 072 A discloses a device on a carding machine for textile fibers, wherein in the cover of the drum opposite cover an opening for the supply of air towards the clothing of the drum and at least one opening for the escape of air with short fibers, Trash u. Like. Of the clothing of the drum away. In a simple way, an increased detachment and discharge of short fibers, trash u. Like. To allow from the fiber and the entry of dust u. Like. To exclude safely in the fiber, the opening for the supply of air is connected to a compressed air source. Furthermore, from the GB 2 217 736 A a device in the spinning preparation for detecting by a line, a channel o. The like. Promoted amount of fiber material known, which in turn has a sensing device with a plurality of light emitters and light receivers.

Furthermore it is known the surface any workpieces provided with a so-called flock, which in turn made of synthetic fibers, such as Nylon or polyamide fibers, or natural fibers such as cotton fibers, can exist.

such workpieces can For example, be interior components of motor vehicles, in turn have a solid basic structure.

in the Essentially, it will be first the surface to be flocked of the workpiece wetted with a suitable adhesive. After a no longer timely measure can then the flock on the surface to be flocked mechanically by sprinkling, Blowing, shaking be applied. Recently, however, this is done with the help of a electric field, placing the flock on a pole, for example in the form of a high voltage electrode, and is charged accordingly the field to the opposite pole, here to be flocked and with glue provided workpiece, flies and penetrates the adhesive, ensuring a good anchorage of the flock perpendicular to the workpiece surface in the adhesive to be recorded.

Flock surplus can be vacuumed already at the end of flocking. No later than in connection to however, the drying of the adhesive is the workpiece of flock excess, d. h. to cleanse from insufficiently adherent flock.

These Cleaning becomes predominant by blowing off with compressed air, by brushing (WO 96/27450 A1) and / or by shaking of the workpiece carried out. It is also known that said insufficiently adherent flock to pat off (WO 96/27450 A1).

To the current one However, prior art is a complete discharge of flock surplus not achievable, d. h., From flocked and finished cleaned workpieces is also non-adherent flock triggerable.

Of Furthermore, it is known that the degree of the so-called residual flock fraction on flocked workpieces the quality subordinated assembly and completion operations, making it desirable is to determine the same.

In that regard it is from the US 5,403,884 A. and the US Pat. No. 4,535,121 known to determine the residual flock fraction after a so-called abrasion test.

task The invention is now a test method for determining the releasable To specify flock amount of flocked components, which is suitable is to trigger flock from finally cleaned flocked workpieces whose To determine quantity and to evaluate the cleaning condition in order to Result the cleaning condition of flocked workpieces in a specified quality characteristic to convict. Also It is an object of the invention to provide a suitable device for carrying out the test method to accomplish.

• – Versetzen eines Prüflings in gleichmäßige hochfrequente Schwingungen derart, dass eine voreingestellte Schwingungsfrequenz des Prüflings, die in einem Bereich von etwa 50 Hz bis etwa 100 Hz gewählt wird, über den Prüfzeitraum beibehalten wird,
• – Überlagerung der gleichmäßigen hochfrequenten Schwingungen des Prüflings mit Schwingungen resultierend aus einem auf denselben einwirkenden sporadischen Impuls,
• – Bestimmung der Menge des sich auslösenden Flocks,
• – Erstellen oder Vorgeben eines Schwellwertes für sich auslösenden Flock, und
• – Vergleich der Menge des sich auslösenden Flocks mit dem erstellten oder vorgegebenen Schwellwert sowie Bewertung des Vergleichsergebnisses.

According to the invention the object is achieved according to claim 1 by a test method for determining the triggerable Flockmenge of flocked workpieces by the following to be performed in a defined time unit steps:

• - putting a test object into uniform high-frequency oscillations such that a preset vibration frequency of the test object chosen in a range from about 50 Hz to about 100 Hz is maintained over the test period,
• Superposition of the uniform high-frequency oscillations of the test object with oscillations resulting from a sporadic pulse acting on them,
• Determination of the amount of flock causing it,
• - Create or set a threshold for triggering flock, and
• - Comparison of the amount of the triggering flock with the created or predetermined threshold and evaluation of the comparison result.

The under claims 2 to 9 describe preferred developments or refinements the invention.

After that is provided that the uniform high-frequency Vibrations by an electromagnetically operated vibrator be generated.

As the invention still provides, the vibration generator for compensation fluctuations in the energy network used and to guarantee of reproducible excitation codes by means of a frequency control device with a network independent Output voltage and a variable frequency supplied.

The Frequency control device Insofar the current oscillation amplitude and the phase are continuously measured the generated vibrations and regulates depending on the load through the examinee, as a result of the mass and the mass distribution of the same, the Vibration amplitude such that said preset oscillation frequency of the test piece is maintained.

Of the sporadically on the examinee acting pulse is preferably generated by a knocking unit, wherein the knocking unit pneumatic, hydraulic or electromagnetic can be operated.

Of Furthermore, it is proposed that the test specimen in the course of vibration excitation flows around by ionized air becomes.

According to one further advantageous measure It is suggested that the determination of the amount of triggering flock by weighing it is made.

Finally will suggested that the comparison of the amount of triggering flock with the created or given threshold and the rating the comparison result is carried out by means of a computer unit.

• – einen Schwingungserzeuger zur Erzeugung gleichmäßiger hochfrequenter Schwingungen, der seinerseits mit einem Werkstückadapter zur Aufnahme eines Prüflings wirkverbunden ist, wobei eine voreingestellte Schwingungsfrequenz des Prüflings in einem Bereich von etwa 50 Hz bis etwa 100 Hz gewählt und über den Prüfzeitraum beizubehalten ist,
• – eine Klopfeinheit, zur Erzeugung eines sporadischen und auf den Prüfling einwirkenden Impulses, und
• – eine Wägeeinheit zur Bestimmung der Menge des sich auslösenden Flocks.

The device for determining the triggerable flock amount of flocked workpieces, according to claim 10, at least:

• A vibrator for generating uniform high-frequency oscillations, which in turn is operatively connected to a workpiece adapter for receiving a specimen, wherein a preset oscillation frequency of the specimen is selected in a range of about 50 Hz to about 100 Hz and maintained over the test period,
• - A knocking unit, for generating a sporadic and acting on the specimen pulse, and
• - A weighing unit for determining the amount of flock triggering.

According to one preferred embodiment the vibrator operated electromagnetically.

To the Included in the scope of the invention Furthermore, that the vibration generator, a frequency control device for supply with a mains-independent output voltage and a variable frequency.

Further is provided that the knocking unit for generating a sporadic and on the examinee acting impulse pneumatic, hydraulic or electromagnetic can be operated.

Finally, according to the invention also a Means for feeding from ionized air to the DUT while the vibration excitation of the same and to compare the amount of the triggering Flocks with the created or given threshold value as well as the Evaluation of the comparison result provided a computer unit be.

The Invention will be described below with reference to the drawing illustrated embodiment a suitable device for carrying out the test method according to the invention explained in more detail.

The single figure first shows a parked on the floor base frame 1 on which a framework 2 by means of a plurality of vibration dampers 3 rests. vibration 3 are known per se in various embodiments. In the simplest form these consist of an elastomer material.

Furthermore, on the frame 2 a vibrator 4 arranged, in turn, also via a plurality of vibration dampers 3 has and by means of the same on the frame 2 supported.

The vibrator 4 essentially comprises at least one electromagnet not shown in detail, but known per se, which is suitable for generating high-frequency oscillations.

The magnet armature of the at least one electromagnet is present with a so-called support frame 5 operatively connected, on which a workpiece adapter 6 for receiving a test object 7 fixed, but can be attached releasably.

By the electromagnet thus electromagnetic vibrations are converted into mechanical vibrations and vibration excitation of the workpiece adapter 6 and accordingly also the test object 7 used.

To compensate for fluctuations in the energy network used and to ensure reproducible exciter key figures is the vibrator 4 or its electromagnet not shown in detail frequency control device for the supply of the vibrator 4 or electromagnet associated with a network-independent output voltage and a variable frequency.

Furthermore, a so-called knocking unit 8th provided, in turn, by at least one on the support frame 5 respectively on the examinee 7 acting mass body 9 is formed, wherein in the present case the mass body 9 suspended in the manner of a pendulum.

The knocking unit 8th can be operated pneumatically, hydraulically or electromagnetically, wherein in the preferred embodiment a so-called "pneumatic muscle" 10 is provided, which in turn is suitable, the mass body 9 against the support frame 5 to move.

Such "pneumatic muscle" 10 are known to consist of a contraction tube which expands upon application of an internal pressure in the circumferential direction, which in turn is a tensile force and a contraction movement in the longitudinal direction of the "muscle" is recorded.

Of the Advantage from the use of said "pneumatic muscle" exists in particular in that they have a low weight and high media resistance have a high dynamics, hardly subject to mechanical wear and by the simplest measures adaptable to defined conditions are.

As the single figure can be seen further, is below the specimen 7 a weighing unit 11 to record and determine the amount of the examinee 7 detaching flock 12 during a vibration excitation of the same.

Finally, a means 13 for supplying ionized air 14 to DUT, for example, a nozzle assembly with not shown, but known per se ionization units in the form of so-called ionizing rods provided to the detachment of non-adherent flock 12 beneficial to support.

following becomes the test procedure closer in itself considered.

If a certain number of flocked and finally cleaned workpieces are ready for assembly or dispatch, it is envisaged that a test object 7 to determine the triggerable Flockmenge the test method according to the invention is subjected.

In that regard, the examinee 7 first in a suitable workpiece adapter 6 insert or attach to this and below the workpiece adapter 6 on the frame 5 of the vibrator 4 set.

Now the candidate is 7 by means of the electromagnet of the vibrator 4 in uniform high-frequency oscillations offset by the magnet armature of the electromagnet, on the support frame 5 attacking, this with workpiece adapter 6 and examinee 7 stimulates.

As a result of extensive experiments, a vibration frequency of the uniform high-frequency vibrations of the specimen 7 from about 50 Hz to about 100 Hz.

As already demonstrated above, the vibrator is 4 assigned to compensate for variations in the energy network used and to ensure reproducible excitation indicators expediently not shown in detail frequency control device.

This frequency control unit supplies the vibrator 4 respectively its electromagnet with a mains-independent output voltage and a variable frequency, wherein it continuously measures the current oscillation amplitude and the phase of the generated vibrations and in dependence on the load of the test specimen 7 the oscillation amplitude controls such that a preset oscillation frequency of the specimen 7 over the test period, which should last at least 25 sec.

This measure results in particular from the fact that each candidate 7 due to its specific mass and mass distribution has or causes a specific vibration behavior.

This means for the practice that due to the above measure comfortable also DUTs 7 different mass and mass distribution while ensuring the same boundary conditions (vibration indices) can be excited to vibrate, with the frequency control device according to an automatic calibration automatically to the vibrator 4 and the selected oscillating test piece 7 adapts.

In the context of the extensive experiments it was further found that with regard to the discharge of insufficiently adherent particles of the flock 12 an additional vibration excitation by a knocking unit 8th brings particularly good results when such a pulse sporadically on the test specimen 7 is applied, in the present case, the mass body 9 with a certain predetermined force on the support frame 5 meets and generates vibrations that overlap with the high-frequency vibrations.

By sporadic is meant that the temporal sequence of the pulses to release flock 12 is not constant.

Furthermore, it was found that by flowing around the test specimen 7 with ionized air 14 the static charge of the insufficiently adherent flock 12 is eliminated and the same also better from the surface of the specimen 7 solves.

The now in the course of the vibration excitation of the test 7 Solvent flock is in turn by means of the weighing unit 11 detected and preferably on a control panel 15 displayed for the operation of the device according to the invention.

The determined amount of flock is now with a created or predetermined threshold for itself triggering flock 12 compared and evaluated the result of the comparison, which can be accomplished both by the machine operator or a third party, but preferably by means of a computer unit, not shown.

The above exemplary embodiment focuses on a test object 7 from. However, the invention also covers the case when, according to a specific sampling plan, a plurality of test pieces 7 in the form of an inspection lot successively treated according to the invention by vibrational excitation and the total amount of flock detected and finally the triggerable Flockmenge per specimen 7 is calculated.

1

base frame

2

frame

3

vibration

4

vibrator

5

holding frame

6

Workpiece Adapter

7

examinee

8th

knock unit

9

mass body

10

pneumatic muscle

11

weighing unit

12

Flock

13

Means for supplying ionized air 14

14

ionized air

15

Control panel

Claims (15)

Test method for determining the triggerable flock quantity of flocked workpieces, comprising the following steps to be performed in a defined time unit: - displacing a test object ( 7 ) in uniform high-frequency oscillations such that a preset oscillation frequency of the specimen ( 7 ), which is chosen in a range from about 50 Hz to about 100 Hz, is maintained over the test period, - superposition of the uniform high-frequency vibrations of the test object ( 7 ) with vibrations resulting from a sporadic momentum acting on it, - determination of the amount of flocking ( 12 ), - creating or setting a threshold for triggering flock ( 12 ), and - comparison of the amount of flocking ( 12 ) with the created or predetermined threshold and evaluation of the comparison result. A method according to claim 1, characterized in that the uniform high-frequency oscillations by an electromagnetically driven vibration generator ( 4 ) be generated. Method according to one of claims 1 and 2, characterized in that the vibration generator ( 4 ) is supplied to compensate for variations in the energy network used and to ensure reproducible excitation codes by means of a frequency control device with a network-independent output voltage and a variable frequency. A method according to claim 3, characterized in that the frequency control device continuously measures the current oscillation amplitude and the phase of the generated vibrations and in dependence on the load by the test specimen ( 7 ), resulting from the mass and the mass distribution of the same, which regulates oscillation amplitude such that said preset oscillation frequency of the specimen ( 7 ) is maintained. A method according to claim 1, characterized in that the sporadically on the test specimen ( 7 ) impulse by a knocking unit ( 8th ) is produced. Method according to claim 5, characterized in that the knocking unit ( 8th ) is operated pneumatically, hydraulically or electromagnetically. Method according to one of claims 1 to 6, characterized in that the test specimen ( 7 ) in the course of the vibration excitation of ionized air ( 14 ) is flowed around. A method according to claim 1, characterized in that the determination of the amount of flock triggering ( 12 ) is made by weighing it. A method according to claim 1, characterized in that the comparison of the amount of flock triggering ( 12 ) is performed with the created or predetermined threshold and the evaluation of the comparison result by means of a computer unit. Device for determining the triggerable flock amount of flocked workpieces, comprising at least: - a vibration generator ( 4 ) for generating uniform high-frequency vibrations, which in turn with a workpiece adapter ( 6 ) for receiving a test object ( 7 ), wherein a preset oscillation frequency of the specimen ( 7 ) is selected in a range of about 50 Hz to about 100 Hz and is to be maintained over the test period, - a knocking unit ( 8th ), to produce a sporadic and to the test specimen ( 7 ) acting pulse, and - a weighing unit ( 11 ) for determining the amount of flocking ( 12 ). Apparatus according to claim 10, characterized in that the vibration generator ( 4 ) is electromagnetically operated. Device according to one of claims 10 and 11, characterized in that the vibration generator ( 4 ) is associated with a frequency control device for supplying the same with a network-independent output voltage and a variable frequency. Apparatus according to claim 10, characterized in that the knocking unit ( 8th ) for generating a sporadic and on the test specimen ( 7 ) acting pulse is pneumatically, hydraulically or electromagnetically operated. Device according to one of claims 10 to 13, characterized in that a means ( 13 ) for supplying ionized air ( 14 ) to the test item ( 7 ) during the vibration excitation of the same is provided. Device according to one of claims 10 to 14, characterized in that for comparison of the amount of the triggering flock ( 12 ) is provided with a created or predetermined threshold value and for evaluating the comparison result, a computer unit.