DE102022130216A1 - distance sensor - Google Patents

Abstract

Distance sensor, comprising a probe, a reference surface and a sensor device, wherein the probe is operatively coupled to the reference surface and the sensor device detects a distance between the reference surface and the sensor device, and wherein the probe and the reference surface are movable in relation to the sensor device.

Description

TERRITORY OF APPLICATION

The present application relates to sensors. In particular, the present application relates to a distance sensor.

BACKGROUND

In the field of additive manufacturing, an additive manufacturing machine is also referred to as a 3D printer. In 3D printing, parts or workpieces are built/created/generated by sequentially applying layers of build material(s). Each layer consists of at least a single bead or strand of construction material.) The construction material can be any thermoplastic material, e.g. e.g. plastic. Furthermore, the additive manufacturing process can be the FDM, FFF or FLM process or another process for applying polymer melts. The build material fed to the 3D printer can be, but is not limited to, filament or granulated thermoplastic material.

The 3D printer typically includes at least one print head that moves in three directions along a print path or a toolpath. There are also 3D printers with a print head that moves in two directions (usually the X and Y directions or axis) and a print bed (the surface or structure on which the work piece(s) is created). /will) moving in the third direction (usually the Z direction or axis).

When starting to create a part, the 3D printer generally needs to be calibrated to ensure high quality of the printed part. However, calibration operations can also be performed during printing to compare the actual shape (e.g. height or Z-direction dimension) to the shape/height that the part is programmed to have. In order to carry out the calibration, it is often advantageous to recognize a distance or to create a height profile. However, the currently available sensors are only suitable to a limited extent for these tasks or are difficult to integrate into a system.

SUMMARY

The aim of the present application is to overcome the aforementioned disadvantages. This is achieved by the subject matter of the appended independent claims. Selected embodiments are set out in the dependent claims. Each of these claims alone or in any combination with the other dependent claims may constitute an embodiment of the present application. Although the present disclosure is discussed in the field of additive manufacturing, the distance sensor can be applied in various fields and is certainly not limited to use in additive manufacturing.

According to one aspect of the present application, a distance sensor includes a probe, a reference surface and a sensor device. The probe is operatively connected to the reference surface. The sensor device scans a distance between the reference surface and the sensor device. The probe and the reference surface can be moved relative to the sensor device (e.g. linear movement). This means that the probe and thus the reference surface can change a distance between the reference surface and the sensor device. The sensor device can be, for example, a capacitive sensor device, a radar sensor device, a light-emitting sensor device or an inductive sensor device. When the probe is brought into contact with a surface and is moved along that surface with a fixed height of the sensing device in relation to the first point of contact of the probe and the surface, then a change in the height of the surface is translated into a change in the distance between the reference surface and the sensor device implemented. In other words, if e.g. the distance sensor is mounted on a known gantry system of a 3D printer and the probe is brought into contact with a surface of a print bed, the height above the print bed (e.g. z-position) of the gantry is fixed and the probe e.g. moved along a path or path on the print bed. Every projection (e.g. printed structure) or every indentation (e.g. deformation of the printing bed) leads to a change in the distance between the reference surface and the sensor device and thus to a change in the signal emitted by the sensor device. A height profile can be created by moving the distance sensor along a path. This can have the advantage that you get a sensor that can detect a distance or a difference in height, for example. Although the distance sensor is explained in relation to a 3D printer, the present disclosure is not limited thereto. A distance sensor according to the present application can be used in connection with numerous different devices.

According to one aspect of the present application, the probe head of a distance sensor has at least one rounded surface. This can the Have the advantage that the probe can move more easily on, for example, a path or track and over, for example, differences in elevation. This can further reduce the stresses placed on the distance sensor by movement along a track.

According to one aspect of the present application, the probe of a distance sensor is at least partially a sphere. This can have the advantage that the probe can move more easily on e.g. a path and over e.g. height and/or structural differences (e.g. steps).

According to one aspect of the present application, the probe of a distance sensor is a sphere. This can have the advantage that the probe can move even more easily on e.g. a path and over e.g. differences in height when it is e.g. B. rolls over a surface.

According to one aspect of the present application, the probe of a distance sensor and the reference surface are in one piece. This can have the advantage that the distance sensor is easier to manufacture and can work more reliably.

According to one aspect of the present application, the probe of a distance sensor is a unitary element and the reference surface is comprised of a reference element. This can have the advantage that the probe can be optimized at the same time, e.g. to move more easily over a surface and the scanning or detection of the reference surface by the sensor device can be improved.

According to one aspect of the present application, the probe head of a distance sensor is movable with respect to the reference surface. This can be a linear movement. This can have the advantage that, at the same time, the probe can be optimized in order, for example, to move more easily over a surface and the scanning or detection of the reference surface by the sensor device can be improved.

According to one aspect of the present application, the distance sensor further includes a locking mechanism operable to lock the reference surface in at least one position. This can have the advantage that cleaning of the distance sensor is made easier, for example.

According to an aspect of the present application, the distance sensor further includes an actuator connected to the probe or reference element. This can have the advantage that cleaning and/or maintenance of the distance sensor is easier, for example.

According to one aspect of the present application, the distance sensor also includes a housing which at least partially movably accommodates or encloses the probe and the reference surface. This can have the advantage that the probe is guided or supported by the housing and the moving parts are protected by the housing.

According to one aspect of the present application, the housing of a distance sensor also includes at least one opening in the area of the probe. This can have the advantage that dirt can be blown out of the housing by applying compressed air to the opening.

According to one aspect of the present application, the reference element of a distance sensor includes an at least partially tapering contact surface, which is intended to contact the probe. This means that the probe is received or guided to a certain extent by the reference element. For example, the contact surface can have a conical shape and the probe can be a sphere. The probe then centers itself on the contact surface and is also guided or supported by the contact surface. This can have the advantage that the probe has fewer points of contact with the reference element and therefore less friction and consequently less stress is exerted on the distance sensor.

According to one aspect of the present application, the distance sensor further includes a spring operatively coupled to the probe and operable to bias the probe away from the sensor device. This can increase the accuracy of the distance sensor when the probe is pressed against a surface, for example.

According to one aspect of the present application, the feeler element or the reference element of a distance sensor at least partially encloses the sensor device. This can have the advantage that the sensor device is better protected against external influences.

According to one aspect of the present application, the reference surface of a distance sensor comprises a reference plate which is designed in such a way that it can be detected by the sensor device. This can be the case, for example, if the probe or the reference element consist of a material that cannot be detected by the sensor device. This could be the case, for example, if the probe or the reference element was printing Parts are made of plastic and the sensor device is an inductive sensor, for example. The reference plate added to the probe or reference element makes it detectable for the sensor device. This can have the advantage that the probe or the reference element can be made from a less expensive material.

According to an aspect of the present application, the housing includes teeth (protrusions) that are in contact with the probe. This can have the advantages of reducing friction between the probe and the housing and allowing accumulated debris to fall out of the housing.

Each of the above aspects is to be considered a separate invention. The aspects can be freely combined with each other and each feature that is not described as being dependent on another feature can also be freely combined with another. The features of the disclosed method can be integrated into an apparatus and vice versa.

character list

• 1 zeigt schematisch einen Querschnitt durch eine Ausführungsform der Anmeldung.
• 2 zeigt schematisch einen Querschnitt durch eine weitere Ausführungsform der Anmeldung.
• 3 zeigt schematisch eine perspektivische Ansicht von unten der in den 1 und 2 dargestellten Ausführungsformen.
• 4 zeigt schematisch einen Querschnitt durch eine weitere Ausführungsform der Anmeldung.
• 5 zeigt schematisch eine perspektivische Ansicht von unten der in 4 dargestellten Ausführungsform, ähnlich wie in 3.
• 6 zeigt schematisch einen Querschnitt durch eine weitere Ausführungsform der Anmeldung.

Further advantages and features of the present disclosure can be seen from the attached figures. The illustrations are for information only and are not restrictive. The figures schematically describe embodiments of the present application. Therefore, the accompanying figures should not be taken as limiting, for example, the dimensions of the present disclosure.

• 1 shows schematically a cross section through an embodiment of the application.
• 2 shows schematically a cross section through a further embodiment of the application.
• 3 shows schematically a perspective view from below of the in FIGS 1 and 2 illustrated embodiments.
• 4 shows schematically a cross section through a further embodiment of the application.
• 5 shows schematically a perspective view from below of FIG 4 illustrated embodiment, similar to in 3 .
• 6 shows schematically a cross section through a further embodiment of the application.

It should be noted that in the various embodiments described herein, the same parts/elements are denoted by the same reference numbers, however, the disclosure in the detailed description can be applied to all parts/elements with the corresponding reference numbers. The directional terms/position information chosen in this description, such as up, up, down, to the side, sideways, also refer to the directly described figure and can be applied accordingly to the new position after a change of position or another position shown in another figure.

In all figures, the same or similar parts/elements as in the other figures are denoted by the same reference numbers. A detailed explanation of such part/element is therefore given only once for the sake of brevity.

DETAILED DESCRIPTION OF EMBODIMENTS

In 1 a schematic sectional view of a distance sensor 10 is shown first. The distance sensor 10 comprises a probe 20 in the form of a sphere, a reference element 31 with a reference surface 30, a housing 70 and a sensor device 40. The sensor device 40 is intended to generate or emit a signal which is associated with a distance between the reference surface 30 and the sensor device 40 are correlated. In other words: if the distance between the reference surface 30 and the sensor device 40 changes, the signal generated or output by the sensor device 40 also changes.

The reference element 31 surrounds (i.e. encloses) the sensor device 40 at least partially. Since the reference element 31 has to move in relation to the sensor device 40, there is a gap between the sensor device 40 and the reference element 31. A sleeve element 34 seals this gap so that, for example, no dirt can penetrate and falsify a signal from the sensor device 40. A contact surface 32 of the reference member 31 has a conical shape and the probe 20 is formed to fit thereon. As a result, the probe head 20 can rotate slightly relative to the reference element 31 and is held centrally to a central axis.

A locking mechanism 50 is attached to the housing 70 and serves to lock the reference element 31 in a desired position. Likewise, an actuator 60 is attached to the reference element 31 and protrudes from the housing 70 . By means of this actuation 60, the reference element 31 can be moved up and down manually. The housing 70 has openings 71 in the area of the probe 20 . By acting on the openings 71 with compressed air Dirt that has accumulated when the probe head 20 rolls off can be blown out (here downwards in 1 ).

2 shows a further embodiment of the present application in a schematic cross-sectional view, which corresponds to the embodiment of FIG 1 resembles. Therefore, only the differences are explained in detail. Here, a probe element 33 comprises the reference surface 30 and the probe head 20. An actuator 60 and a locking mechanism 50 are coupled to the probe element 33, mutandis to the reference element 31 in FIG 1 . The probe 20 of the probe element 33 is a hemisphere and openings 71 are also arranged in a housing 70 in the area of the probe 20 . The button element 33 also encloses the sensor device 40 at least partially, in accordance with the disclosure of FIG 1 . A sleeve element 34 covers a gap between the feeler element 33 and the sensor device 40 . A reference plate 35 includes the reference surface 30. The reference plate 35 consists of a material that can be scanned or detected by the sensor device 40 if the probe 20 consists of a material that can be detected by the sensor device 40 only with difficulty. The reference plate 35 is optional in all embodiments.

3 is a schematic and perspective view from below of the distance sensor 10. 3 applies to the embodiments of 1 and 2 equally. The probe 20 visibly protrudes from the housing 70 . The opening 71 in the housing 70, which is located in the area of the probe 20, is shown. The actuation 60, which is either connected to the reference element 31 ( 1 ) or the key element 33 ( 2 ) is connected also protrudes from the housing 70.

4 12 shows a further embodiment of the present application in a schematic cross-sectional view, similar to the embodiment of FIG 2 . Here, too, a probe element 33 includes a probe 20 and a reference surface 30. In addition, the probe element 33 at least partially surrounds a sensor device 40. In the embodiment of FIG 4 however, there is no sleeve member 34 as this is optional in all embodiments. In this embodiment, an actuation 60 is a blind hole in the button element 33. In addition, it is optional in all embodiments to design the actuation 60 as a recessed or protruding structure. In the present embodiment, there are no openings 71 in the case 70 . A spring 80 is arranged between the sensor device 80 and the reference surface 30 of the feeler element 33 . The spring 80 acts on the probe element 33 and thus the reference surface 30 away from the sensor device 40. As a result, the distance between the reference surface 30 and the sensor device 40 is always kept at a maximum. The spring 80 is optional in all embodiments and can be attached at will. The spring 80 is preferably made of a material that does not impair the sensor capability of the sensor device 40 . Alternatively or additionally, the spring 80 can be arranged in a spring space 81 in which the spring 80 cannot impair the sensor device 40 .

5 12 shows the distance sensor 10 of the embodiment of FIG 4 from below and is similar to 3 . However, here the probe 20 is fitted into the housing 70 and protrudes from the housing 70 with the aid of teeth 72 (protrusions) which protrude from the housing 70 in the direction of the probe 20 and receive/guide the probe 20 in the housing 70 . The probe 20 contacts the housing 70 only at the teeth 72 and the gaps between the teeth 72 allow any debris or debris that may have accumulated in the housing 70 to fall out. When the probe 20 is a ball, the teeth 72 reduce friction between the rotating ball and the housing 70 because the contact area is reduced.

6 12 shows a further embodiment of the present application in a schematic cross-sectional view, similar to the embodiment of FIG 1 . The probe head 20 also has the shape of a sphere. However, there is no reference element 31 (or feeler element 33) here, since the sensor device 40 detects the distance from the upper side of the sphere, which is therefore the reference surface 30.

The exemplary embodiments show possible variants of the implementation of the subject of the application, but it should be noted that the subject of the application is not limited to the illustrated exemplary embodiments / variants, but numerous combinations of the exemplary embodiments / variants described here are possible and these combinations in the field within the ability of those skilled in the art motivated by this description.

The scope of protection results from the appended claims. However, the description and drawings should be considered in interpreting the claims. Individual features or feature combinations of the features described and/or shown can represent independent inventive solutions. The subject matter of the independent solutions can be found in the description.

It should also be noted that for a better understanding parts/elements are not true to scale and/or enlarged and/or ver are shown smaller. Not all parts for the function of the distance sensor are shown in the illustrations.

Reference List

10

distance sensor

20

probe

30

reference surface

31

reference element

32

contact surface

33

tactile element

34

sleeve element

35

reference plate

40

sensor device

50

locking mechanism

60

activity

70

Housing

71

opening

72

Tooth

80

Feather

81

spring room

Claims (17)

Distance sensor (10), comprising a probe (20), a reference surface (30), and a sensor device (40), wherein the probe is operatively coupled to the reference surface and the sensor device detects a distance between the reference surface and the sensor device, and wherein the probe and the reference surface are movable in relation to the sensor device. Distance sensor (10) after claim 1 , wherein the probe (20) has at least one rounded surface. Distance sensor (10) after claim 2 , wherein the probe (20) is at least partially a sphere. Distance sensor (10) after claims 2 or 3 , wherein the probe (20) is a sphere. Distance sensor (10) according to one of the preceding claims, wherein the probe (20) and the reference surface (30) are in one piece and are encompassed by a probe element (33). Distance sensor (10) according to one of Claims 1 until 4 , wherein the probe (20) is a one-piece element and the reference surface (30) is comprised by a reference element (31). Distance sensor (10) according to any one of the preceding claims, wherein the probe (20) is movable in relation to the reference surface (30). Distance sensor (10) according to one of the preceding claims, further comprising a locking mechanism (50) intended and suitable for locking the reference surface (30) in at least one position. Distance sensor (10) according to one of the preceding claims, further comprising an actuator (60) which is connected to the probe (20) or the reference element (31). Distance sensor (10) according to one of the preceding claims, further comprising a housing (70) which at least partially encloses the probe (20) and the reference surface (30), the probe and the reference surface being movable with respect to the housing. Distance sensor (10) after claim 10 , wherein the housing (70) comprises at least one opening (71) in the region of the probe (20). Distance sensor (10) according to one of the preceding claims, wherein the reference element (31) comprises an at least partially tapered contact surface (32) which is intended and suitable for being in contact with the probe (20). Distance sensor (10) according to one of the preceding claims, further comprising a spring (80) which is operatively coupled to the probe (20) and is intended and suitable for biasing the probe away from the sensor device (40). Distance sensor (10) according to one of the preceding claims, wherein the feeler element (33) or the reference element (31) at least partially encloses the sensor device (40). Distance sensor (10) according to one of the preceding claims, wherein the reference surface (30) comprises a reference plate (35) which is intended and suitable for being detected by the sensor device (40). Distance sensor (10) according to one of Claims 10 until 15 wherein the housing (70) includes teeth (72) which are in contact with the probe (20). 3D printer comprising a distance sensor (10) according to any one of the preceding claims.

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