DE202010017205U1 - Device for the optical measurement of a pen or rod-shaped body - Google Patents

Abstract

Device for optically measuring a pen or rod-shaped body (1), comprising the following components:
- A about an axis of rotation (D) rotatably arranged chuck unit (2) with at least two motor driven chuck jaws for coaxial with the axis of rotation (D) centered recording and releasably fixed locking the pen or rod-shaped body (1), wherein one with the chuck unit (2 ) is provided in separable operative connection actuator (6) which actuates the chuck unit (2) for purposes of locking or releasing the pen or rod-shaped body (1),
A camera unit (21) having an objective (22) whose optical axis (A) orthogonally intersects the axis of rotation (D),
An illumination beam path emanating from a light source (23) which illuminates the pen or rod-shaped body (1) locked in the chuck unit (2) along the optical axis (A) in the direction of view of the objective (22),
- A light line projector (26, 27) for projecting a line of light on the in the chuck unit (26, 27) locked pen or rod-shaped ...

Description

Technical area

The invention relates to a device for optical measurement of a pen or rod-shaped body, preferably in the form of a reinforcing steel, also called reinforcing bar or reinforcing bar, Moniereisen or called Rippentorstahl. Furthermore, there is a standardization of reinforcing bars. Such rod-shaped body used for reinforcement, ie reinforcement of reinforced concrete structures and are used depending on the dependence of the individual concrete components for the formation of two- or three-dimensional lattice structures, which are completely embedded in concrete by means of suitable formwork. To ensure construction safety standards today only rebars with characteristic flow or yield strengths of at least 500 N / mm ² are used. The structural engineering requirements required for this purpose are, for example, in DIN 1045-1: 2008-08 respectively. DIN 488: 2009-08 regulated.

In addition to the flow or yield strengths required above, it is also necessary to consider the adhesive strength of the reinforcing bar in the concrete, d. H. To create as intimate a connection between the surface of the reinforcing bar and the concrete. For this purpose, the surfaces of the rebars are provided with transverse ribs which are perpendicular or oblique to the rod axis and thus effect an improved anchoring between the rebars and the concrete.

Thus, rebars are known which provide two diametrically opposed longitudinal strips, which rise like a bar over the remaining rod contour of the rebars. Between two longitudinal strips are provided obliquely to the rod longitudinal axis helically extending ribs. Fearing that the rods could twist under tension in the direction of the helix, the screw rotation is mutually oriented on both sides separated by the longitudinal sides rod sides. A trained in this regard and optimized in particular with regard to an improved yield strength rebar is from the DE 977 401 B1 to see that has helical ribbed trains whose ends leak flat before adjacent to the respective longitudinal strips.

Another example of a reinforcing bar with high adhesive strength is the DE 690 07 677 B2 to see that provides a plurality of individual rib-like segments formed with different angular arrangement on the concrete bar steel surface.

The above two examples for the formation of high-strength concrete or reinforcing steels are merely intended to express that today there are a large number of differently designed rebars of various shapes, which differ from each other due to their design, diameter and rib shape.

To assess and ensure the mechanical strength of the present in different embodiments of rebars testers are known with which Belastbarkeits- or breaking limits are quantitatively accurately determined. If, on the other hand, the binding quality or the quality of the bond strength of concrete rods in concrete is to be assessed, the surface contour of the reinforcing bars must be measured in terms of diameter and rib shape and their conformity verified with a corresponding standard specification. This task is usually carried out by certified measuring laboratories of the standard organizations and institutes, which ultimately decide on the usability of the respective rebars for certain construction companies.

State of the art

Within the framework of the above-mentioned standard organizations and institutes, the concrete bar steels to be assessed for bond quality or adhesion are determined manually with the aid of suitable length and angle measuring devices with respect to distinctive geometric features of the respective test items such as diameter, rib height, rib length, rib angle, rib width, rib spacing and rib flanks measured. The measured values determined in this case are entered manually in tables and compared with corresponding nominal values and tolerance values listed in tabular form. As a result, it is determined whether the rebar to be tested with the test specifications is "compliant" or "non-compliant". It is obvious that the manual test practice is time-consuming and cost-intensive, on the other hand, it has a test accuracy that depends systemically on the factor "human".

Presentation of the invention

The invention has for its object to exempt the above-described review of the bond strength or binding quality of rebars of the influence factor "human" and to objectify the quality of the test result. In addition, it is desirable to perform the review quickly and cost-effectively, preferably fully automatically and still obtain a reliable test result on the adhesion of a reinforcing steel.

The solution of the problem underlying the invention is specified in claim 1. The solution ideas advantageously further features are the subject of the dependent claims and in particular from the description with reference to the embodiment shown in the figures.

For objectified detection of the bond strength or bond quality of rebars, the geometry detection of a rebar to be tested is carried out with the aid of a computer-aided, automated measuring device using optical detection systems. For this purpose, about 20 cm long sample body is separated from a test to be checked rebar steel, which is used for optical contour detection in the solution designed device. For further description of the device according to the invention, reference will generally be made to a pin-shaped or bar-shaped body, instead of the term "reinforcing bar sample", especially as the solution device according to the invention to be described hereinafter is capable of forming the surface contour of generally pin-shaped or bar-shaped bodies to capture, such as body in the form of the already explained above rebars but also in the form of screws, threaded sections, or similar long parts.

The device according to the solution has a rotatable about a rotation axis arranged chuck unit with at least two motor driven chuck jaws, in which the optically to be measured pen or rod-shaped body centric with a rod end is used stinrseitig and can be locked releasably fixed for investigation purposes. In addition, a camera unit is provided with a lens which has an optical axis which is oriented orthogonally to the axis of rotation about which the chuck unit and, ultimately, the rod-shaped body centrically locked in the chuck unit rotates. An additionally provided light source emits a so-called illumination beam, which illuminates the pen or rod-shaped body locked and rotating in the chuck unit along the optical axis of the objective and in the direction of the objective so that the camera unit can move the rotating pen or rod-shaped body in its direction full silhouette captured in the light of the light source. In the beam direction of the illumination beam behind the rotating body, a reflector surface is mounted, on which the illumination beam is reflected, so that the rotating body presents itself from the viewing direction of the camera unit in a reflected light and backlighting. In this way, exactly the silhouette of the body in the camera unit is distinguished.

In addition, a light line projector for projecting a light line on the pen or rod-shaped body locked in the chuck unit is formed and arranged so that the light line coincides with the rotation axis and the light-line beam path outgoing from the light line projector coincides with the optical axis of the lens Angle α ≠ 0 °, preferably 20 ° ≤ α ≤ 40 °, particularly preferably α = 30 °. With the help of the light line projector, the surface of the pen or rod-shaped body can be detected using the so-called light-section method, in which the light line imaged on the surface of the pen or rod-shaped body of the camera unit, which has a spatially resolving image sensor, preferably in the form of a CCD chips, recorded and evaluated accordingly.

The combination of the two above-described optical observation, on the one hand, the spatially resolved detection of the side view of the pen or rod-shaped body and the other surface contour detection by light-section method, it is possible after rotation of the pen or rod-shaped body of at least 360 ° about the body longitudinal axis All relevant geometric features such as diameter, rib height, rib length, rib angle, rib width, rib distance and rib flank that are required and relevant for assessing the adhesive strength can be determined and evaluated with sufficient accuracy.

Likewise, however, the geometry and contour detection of comparable pen or rod-shaped bodies is possible. The solution according to the device is designed in a preferred embodiment as a portable unit and completely integrated in a housing, so that no specially trained personnel is required to carry out an optical measurement of a pen or rod-shaped body. Rather, it requires only a centered introduction of the body to be examined in the chuck unit for measuring a pen or rod-shaped body. The actual measuring process takes place completely automatically after appropriate locking. Only for the removal of the pen or rod-shaped body to be measured requires an end locking and appropriate removal of the body from the corresponding measuring device.

The optical image information obtained by the measuring device, which the camera unit receives from the corresponding body during a measurement of the pen or rod-shaped body, is evaluated in the context of a corresponding computer-based evaluation unit and transmitted via a suitable interface for a further output provided, for example, to an external monitor unit.

Brief description of the invention

The invention will now be described by way of example without limitation of the general inventive idea by means of embodiments with reference to the drawings. Show it:

1 perspective view of all components of a solution designed device,

2 perspective view into a housing enclosing the components according to the solution,

3a , b perspective two-sided view of the actuator unit for actuating the stand-on unit,

4 Top view of a housing with integrated components of the device according to the invention as well as

5 perspective view into a housing for illustrating components for evaluation and storage of the optical signals detected by the camera unit.

Ways to carry out the invention, industrial usability

1 shows a perspective view of all the relevant components of a device according to the solution for performing the optical measurement of a pen or rod-shaped body 1 in the case of in 1 illustrated embodiment represents a ribbed rebar, which typically has a length of 20 cm and one end face into a chuck unit 2 empties. The chuck unit 2 is with two opposing, comb-like interlocking jaws 3 equipped by the pen or rod-shaped body 1 centric between the two jaws 3 can be locked. The entire chuck unit 2 is also a centering disc 4 on an electric motor driven turntable 5 bolted so that the chuck unit 2 is mounted rotatably about a rotation axis D. The axis of rotation D should coincide with the symmetry axis of the chuck unit 2 locked pen or rod-shaped body 1 coincide. For this purpose, it is the inner contour of the jaws 3 for gripping and centric locking of the pen or rod-shaped body 1 suitable form, so that a longitudinally to the rotation axis D tumble-free rotation of the pen or rod-shaped body 1 is guaranteed. In an advantageous embodiment, it may well be useful to provide three or more interlocking chuck jaws, through which the pen or rod-shaped body 1 radially centric enclosed and can be locked.

For actuating the chuck unit 2 ie for activating the radially directed movements of the chuck jaws 2 both for the process of locking and for the process of re-releasing is immediately adjacent to the on the turntable 5 rotatably mounted chuck unit 2 an actuator unit 6 provided, if necessary, in engagement with the chuck unit 2 occurs. To explain the operation of the in 1 merely summarily referred to actor 6 will be referred to the comments below on the 2a and b.

Furthermore, the solution according to the invention device for optical detection of the outer contour of the pen or rod-shaped body 1 a camera unit 21 , preferably in the form of a CCD camera in front, via a mounting bracket 32 and a lens holding plate 30 firmly on a mounting plate 34 is arranged. With the camera unit 21 is a telecentric lens via a C-mount female thread 22 connected by the lens holding plates 31 and 30 is fixed, both via slot fasteners on the mounting plate 34 are attached. A telecentric lens 22 Assignable optical axis A is so relative to the chuck unit 2 arranged so that the optical axis A perpendicularly intersects the axis of rotation D.

In addition, on the object plate 31 a light source 23 , preferably a red light source 23 is provided, which generates a not further illustrated illumination beam path through the lens 22 along the optical axis A in the direction of the lens 22 the pen or rod-shaped body 1 illuminated. In addition, in the illumination beam path behind the pen or rod-shaped body 1 a reflector surface 24 , Preferably, a reflector film provided for generating a backlight situation, under which the camera unit 21 the pen or rod-shaped body 1 can be spatially resolved. In this transmitted light illumination situation, the camera unit can 21 the silhouette of the pen or rod-shaped body 1 exactly to measure. In addition to extraneous light, which is a sharp and high-contrast image of the pen or rod-shaped body 1 can interfere with, is in the beam path of the camera 21 or the lens 22 or between camera 21 and lens 22 an optical filter 25 introduced for external light blocking.

Finally, next to the lens holding plate 31 a holder 33 firmly on the mounting plate 34 mounted on which a light line projector in the form of a laser 26 as well as one with the laser 26 connected line optics 27 is appropriate. The through the line optics 27 fan-shaped expanded laser beam 28 generated on the surface of the pen or rod-shaped body 1 a strip of light 29 , the same about the lens 22 from the camera unit 21 is detected. The laser 26 and the line optics connected thereto are designed and arranged such that the generated light strip 29 coincides with the axis of rotation D. In addition, the fan-shaped expanded laser beam closes 28 with the optical axis A of the lens 22 an angle α, which is in the range between 20 ° and 40 °, but preferably 30 ° and thus fulfills ideal light-section conditions, which make it possible the surface contour of the rotating pen or rod-shaped body 1 in the way of the light section method with the help of the camera unit 21 capture. Since the laser wavelength is in the red spectral range and selectively the color filter 25 is able to transmit, the recordings are made with respect to the silhouette and the light section recording time in a row.

In the 1 illustrated components are as small as possible and easily formed so that they find space within a portable housing G space. Such a housing G with partial insight is in 2 represented, which contains all the components explained above. The already explained components are also in 2 provided with the corresponding reference numerals, so that can be dispensed with a repeated description of these components. The preferably made of metal housing G has an opening 35 over which the pen or rod-shaped body to be examined 1 from above into the area of the chuck unit 2 can be introduced. For actuating the chuck unit 2 are laterally on the housing G two actuation buttons 7 . 8th provided, of which the operating knob 7 the locking process triggers and the operating knob 8th the process of loosening the chuck again 2 for the subsequent removal of the pen or rod-shaped body 1 initiated. Furthermore, there are various interfaces 38 . 39 . 40 on the lower right edge of the housing for connecting external equipment. The connection 37 represents the network connection.

To explain the operation of the actuator 6 , the locking as well as the release of the chuck unit 2 serve, be on the 3a and b, each showing a perspective view from two different directions of view of the actuator unit. Such is a geared motor 10 provided, which is able to put a horizontally oriented rotary shaft W in rotation. Along the rotation shaft W is guided in a groove Achsverlängerungs bush 12 provided at the output end of a key element 13 is provided in the form of a square wrench. The axle extension bush 12 is rotatable in a ball bearing 14 taken in a ball bearing retainer 15 is mounted radially. The ball bearing retaining ring 15 is over a lever 18 with a solenoid 16 connected in a lifting magnet holder 17 is attached. Will the solenoid 16 activated so that the lifting magnet piston 16 ' is retracted, so is due to the lever 18 the square key 13 along a defined by the axis of the shaft W linear axis transferred to an extended position. If, however, the solenoid is 16 deactivated, then the square key 13 in its rear starting position via the lever 18 recycled. So much for the general functioning of the actuator 6 ,

In conjunction with the in 4 shown top view of the entire device opens up the activation of the chuck unit 2 in the following way: By pressing the as a tension button 7 designated actuator unit (see also 2 ) becomes the solenoid 16 energized, whereupon the solenoid 16 Attracts and over the lever 18 the square key 13 in one on the chuck unit 2 provided "keyhole" S pushes in.

At the same time the geared motor 10 made to rotate, causing the chuck jaws 3 for centric locking of the pen or rod-shaped body 1 to move towards each other. Is the clamping or locking process completed, ie embrace the chuck jaws 3 the pen or rod-shaped body 1 subjected to force, so the motor current of the geared motor increases 10 and illuminates a light bulb (not shown) connected in series with the motor winding, which is preferably visibly attached to the housing. The illumination of the lamp increases its electrical cold resistance and thus limits the power of the braked gear motor at the same time 10 , By visual signaling, a person experiences the completion of the locking process, so that they the tension button 7 lets go.

By releasing the tension button 7 becomes the current of the solenoid 16 interrupted, causing the solenoid 10 is relaxed and the Hubmagnetkolben 16 ' withdrawal begins. As a result, the square key becomes 13 from the keyhole S within the chuck device 2 pulled out. To assist this process, it is envisaged that the geared motor 10 initiated a small reverse rotation of the shaft W, so that the square key 13 easier from the keyhole S of the chuck unit 2 pull out. For this purpose are two slots 20 (please refer 3b ) in the axle extension bushing 12 incorporated the a limited freewheel of the coupling of the square wrench 13 enable. It also ensures that the short-term turning back of the gear motor 10 to no unintentional release of the pen or rod-shaped body 1 in the chuck unit 2 leads.

Finally, be on the 5 referenced, which is a perspective oblique view into the housing G without the on the mounting plate 34 applied optical components shows. So it can be seen that below the mounting plate 34 inside the case G a hard disk 42 , a power supply 43 as well as the computer board 44 are housed, are made by both the control of all components as well as the signal evaluation and storage.

fan units 41 ensure that the operating temperature of the corresponding electronic components is not exceeded. In a particularly preferred manner, at least the housing side walls, which comprise the workpiece part, ie the area of the chuck unit together with the actuator, are made of a green transparent material which, on the one hand, provides a controlling insight into the housing interior and, on the other hand, filters out disturbing stray light components.

LIST OF REFERENCE NUMBERS

1

pen-shaped or rod-shaped body, reinforcing steel

2

Chuck unit

3

Chuck jaws

4

centering

5

motor driven turntable

6

actuator

7

tension button

8th

Operation button to release

9

On / off switch

10

gearmotor

11

Mounting foot

12

extension jack

13

Square key

14

ball-bearing

15

Ball race ring

16

solenoid

17

Hubmagnethalter

18

lever

19

Retraction spring

20

Freewheel slots

21

camera unit

22

telecentric lens

23

Light source, telecentric infrared light source

24

reflector sheet

25

infrared filter

26

laser

27

line optics

28

laser fan

29

laser line

30

Lens retaining plate

31

Lens retaining plate

32

Camera mounting bracket

33

laser holder

34

mounting plate

35

Opening for examinees

37

LAN port

38

Graphics Card Connector

39

Power connector

40

USB ports

41

Fan

42

hard disk

43

power adapter

44

computer board

45

Keyhole for external actuation of the locking mechanism in the chuck unit

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 977401 B1 [0003]
• DE 69007677 B2 [0004]

Cited non-patent literature

• DIN 1045-1: 2008-08 [0001]
• DIN 488: 2009-08 [0001]

Claims (7)

Device for the optical measurement of a pen or rod-shaped body ( 1 ), comprising the following components: - a chuck unit rotatably arranged about an axis of rotation (D) ( 2 ) with at least two motor-driven chuck jaws for coaxial with the axis of rotation (D) centered recording and releasably fixed locking of the pen or rod-shaped body ( 1 ), one with the chuck unit ( 2 ) can be brought into separable operative connection ( 6 ) is provided, the the chuck unit ( 2 ) for purposes of locking or releasing the pen or rod-shaped body ( 1 ), - a camera unit ( 21 ) with a lens ( 22 ) whose optical axis (A) orthogonally intersects the axis of rotation (D), - one of a light source ( 23 ) outgoing illumination beam path that in the chuck unit ( 2 ) locked pen or rod-shaped body ( 1 ) along the optical axis (A) in the direction of the lens ( 22 ), - a light line projector ( 26 . 27 ) for projecting a line of light onto that in the chuck unit ( 26 . 27 ) locked pen or rod-shaped body ( 1 ) is formed and arranged such that the light line coincides with the axis of rotation (D) and that the light line projector ( 26 . 27 ) assignable light-line beam path ( 28 ) with the optical axis (A) of the lens ( 22 ) includes an angle α not equal to 0 °, - an evaluation and storage unit ( 42 . 44 ) for the acquisition, evaluation and storage of the camera unit ( 21 ) detected optical signals. - All components are housed within a housing (G), which is designed as a portable unit. Apparatus according to claim 1, characterized in that in the illumination beam path in the chuck unit ( 2 ) locked pen or rod-shaped body ( 1 ) downstream of the illumination beam path reflecting surface ( 24 ) is arranged. Device according to claim 1, characterized in that the actuator ( 6 ) a key element which can be deflected along a linear axis (L) ( 13 ), which is motor-driven in rotation about the linear axis (L) displaceable and in a direction to the linear axis (L) deflected position in engagement with the chuck unit ( 2 ) and in an undeflected position of the chuck unit ( 2 ) is disconnected. Device according to one of claims 1 to 3, characterized in that the line projector a laser ( 26 ) with a downstream line optical system ( 27 ) for producing a fan-shaped expanded laser beam ( 28 ) having. Device according to one of claims 1 to 4, characterized in that α corresponds to an angle between 20 ° and 40 °, preferably α is equal to 30 °. Device according to one of claims 1 to 5, characterized in that the camera unit ( 21 ) is a CCD camera and the lens ( 22 ) is a telecentric lens. Device according to one of claims 1 to 6, characterized in that the pin-shaped or rod-shaped body ( 1 ) is a reinforcing steel, a reinforcing iron, a Rippentorstahl, a thread, a threaded portion or a screw.

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