Detector with integrated hold function

Abstract

Detector with Integrated Hold Function. The present invention relates to a presence or proximity detector (1) comprising, at least, a detection element (2), at least one circuit (3) for processing the signals delivered by the latter, also providing the power supply or excitation of said element (2), and a protective housing (4) enclosing said element (2) and said circuit (3) and having a wall (5) defining a sensitive face (6) in relation to the detection element (2), as well as means (7) for electrical connection of said circuit (3). This detector (1) is characterized in that it also comprises at least one magnet (8), of the permanent type or electromagnet, mounted in the protective housing (4), in the region of the sensitive face (6), the aforementioned element (2) and circuit (3) being selected and / or configured such that the presence or proximity detection function is not disrupted by this magnet (8).Figure to be published with the abbreviation: Fig. 1A.

Description

Title of the invention: Detector with integrated holding function

[0001] The present invention relates to the field of industrial devices for detecting and handling metal parts, and has as its object an improved presence or proximity detector, with integrated holding function, and an industrial workstation comprising at least one such detector.

[0002] Many varieties of detectors of the aforementioned type are already known, in particular inductive detectors and mechanical contact pressure detectors.

[0003] In particular, inductive detectors have been marketed by the applicant for many years and are, for example, described in documents FR 2 827 677, EP 1 580 889, EP 1 580 536, EP 1 965 177 and EP 2 546 614. A specific detector of this type, called "factor 1", is disclosed by document EP 3 430 443.

[0004] Existing pressure detectors may include transducer cells of different types such as ceramic cells, metallic cells or silicone membrane cells.

[0005] These presence or proximity detectors are often used in association or integrated into gripping devices for parts (especially small parts) which must be positioned and held precisely in relation to at least one other part, with which it must be joined, for example by welding, or cooperate, for example by engagement.

[0006] Currently, these parts are taken, moved, manipulated, held, engaged and / or blocked in a position by specific gripping organs and locking means, magnetic, mechanical (pneumatically, hydraulically or electrically operated grippers), suction or similar, which either integrate the aforementioned detectors or cooperate with them to verify the actual presence and / or the proper position of the expected part.

[0007] This results in complex, costly, and cumbersome workstation constructions, especially when the parts involved are relatively small and must be placed in a high-risk environment. This is the case for small ferromagnetic metal parts (typically weighing a few hundred grams) that must be brought in, placed, and held in position temporarily before being welded together with larger ferromagnetic metal parts.

[0008] The main purpose of the present invention is to overcome these drawbacks, particularly but not limited to the aforementioned context, by proposing a simple, economical and compact solution.

[0009] To this end, it has as its object a presence or proximity detector comprising, at least, a detection element, at least one circuit for processing the signals delivered by the latter, also ensuring the power supply or excitation of said element, and a protective housing accommodating said element and said circuit and having a wall defining a sensitive face in relation to the detection element, as well as electrical connection means for said circuit,

[0010] detector characterized in that it also comprises at least one magnet, of the permanent type or electromagnet, mounted in the protective housing, in the region of the sensitive face, the aforementioned organ and circuit being selected and / or configured in such a way that the presence or proximity detection function is not disturbed by this magnet.

[0011] The invention will be better understood from the following description, which relates to preferred embodiments, given by way of non-limiting examples, and explained with reference to the accompanying schematic drawings, in which:

[0012] [Fig.1A] is a cross-sectional view along a plane perpendicular to its sensitive face of a detector according to a first embodiment of the invention;

[0013] [Fig.1B] is an exploded perspective view of the detector shown [Fig.1A];

[0014] [Fig. IC] is a perspective view of the functional elements of the detector of the [Fig.1A], with the casing removed;

[0015] [Fig.2] is a view similar to that of [Fig.1A], the detector being installed and cooperating with a reference piece;

[0016] [Fig.3A] is a perspective and partially cross-sectional view of a detector according to a second embodiment of the invention;

[0017] [Fig.3B] is a cross-sectional view along a plane perpendicular to its sensitive face of the detector of the [Fig.3A];

[0018] [Fig.4A] is a perspective view of a detector according to a third embodiment of the invention;

[0019] [Fig.4B] is a cross-sectional view along a plane perpendicular to its sensitive face of the detector of the [Fig.4A];

[0020] [Fig.5A] is a perspective view of a detector according to a fourth embodiment of the invention;

[0021] [Fig.5B] is a cross-sectional view along a plane perpendicular to its sensitive face of the detector of [Fig.5A].

[0022] Figures 1 to 5 illustrate different design variants of a presence or proximity detector (1) comprising, at least, a detection element (2), at least one circuit (3) for processing the signals delivered by the latter, also providing the power supply or excitation of said element (2), and a protective housing (4) housing said element (2) and said circuit (3) and having a wall (5) defining a face sensitive element (6) in relation to the sensing element (2), as well as electrical connection means (7) for said circuit (3). This latter circuit may or may not also provide excitation for the sensing element (2), depending on the case and the nature of said element. This circuit (3) may be mounted on a single support (Figures 1, 2 and 4) or distributed over at least two supports (Figures 3 and 5), or include an auxiliary part (3'). The wall (5) may, for example, form part of a cap and extend into a lateral skirt, said cap closing the front end of the main body of the housing (4) in the form of a tube.

[0023] According to the invention, this detector (1) also includes at least one magnet (8), of the permanent type or electromagnet, mounted in the protective housing (4), in the region of the sensitive face (6), the aforementioned member (2) and circuit (3) being selected and / or configured in such a way that the presence or proximity detection function is not disturbed by this magnet (8).

[0024] Thanks to these provisions, the invention provides a detector with an additional function of holding and maintaining in position one or more metallic parts, having a mass compatible with the attractive force generated by the magnet (8). It is thus possible, depending on the contexts and applications of use of the detector (1), to do without specific holding devices or grippers.

[0025] Furthermore, by integrating this additional functionality entirely within the detector housing (1), the dimensions, mounting, and connection of said detector (1) remain unchanged compared to the existing design. To this end, the shape of the minimum magnet (8) present is adapted to the available internal volume within the housing (4), particularly in the region immediately behind the sensing face (6). Although several magnets could be integrated to achieve the functionality (combining several similar or dissimilar magnets for reasons of standardization or to obtain sufficient magnetic force, optimal use of the available space within the housing, etc.), the use of a single magnet (8) is preferred.

[0026] Where appropriate, it may also be considered to modify the configuration or arrangement of the sensing element (2) and / or the circuit (3) to accommodate the magnet (8). The accompanying figures illustrate different forms of detectors (with cylindrical housings with or without external threads, with cylindrical housings of constant or variable diameter, with cubic or parallelepiped housings with a through fixing screw (9)) according to the invention, housing a magnet (8) for the purpose of holding part(s).

[0027] The latter, whether in one piece or composed of several parts forming a block, may consist of a permanent magnet (8) making the additional functionality completely autonomous (neodymium or AlniCo magnet, or even ferrite). However, the magnet (8) may also be an electromagnet powered and possibly controlled by via the connection means (7) of the detector (1), and thus allowing, if necessary, to activate and deactivate at will the additional functionality provided, or even to control the intensity of its action.

[0028] The attractive force of the magnet is of course sufficient to keep the part(s) concerned in the detection field of the organ (2), in particular against the face (5) or another support surface, when the detector (1) is mounted in recess for example.

[0029] The electrical connection means (7) can either be integrated into a rear part (7') of the housing (4), or be offset from the latter (presence of a connecting cord - figures 4).

[0030] According to a first embodiment of the invention, illustrated in several constructive forms, the detector consists of an inductive detector (1) with a detection element (2) of the LC circuit type and a suitable excitation and signal processing circuit (3), preferably a "factor 1" type inductive detector. The permanent magnetic field generated by the magnet or magnets (8) does not disturb the alternating field used for detection. In a detector of this type, for example, known from the applicant's aforementioned document EP 3430443, the magnet can be arranged around or behind the PCB coil L.

[0031] According to a second variant of the invention, not shown, the detector consists of a mechanical contact pressure detector (1) with a detection element in the form of a transducer cell and a suitable signal processing circuit.

[0032] Finally, according to a third variant of the invention, not shown, the detector (1) comprises a hybrid detection element combining the functions of inductive detection, by means of a detection element (2) of the LC circuit type, and mechanical pressure detection, by means of a detection element in the form of a transducer cell, as well as suitable excitation and signal processing circuits.

[0033] In all these variants, the shape of the magnet or magnets (8) present will be advantageously adapted to the space available in the housing (4), the nature, positioning and dimensions determining the force of attraction produced.

[0034] Preferably, said at least one magnet (8) is arranged in the protective housing (4), preferably in the immediate vicinity of the sensitive detection face (6), so as to generate a magnetic attraction force (MAF) along a direction (D) substantially perpendicular to the plane of said sensitive face (6). The strength of the magnetic field of the magnet (8) is dimensioned to ensure that the part(s) to be held (typically a few hundred grams) is held at a distance less than the range or detection distance of the detector (1).

[0035] As shown in Figures IA, 2, 3B and 4B, at least part of the sensing member (2) is disposed on the inner side of the wall (5) defining the sensitive face (6) and the detector (1) includes a magnet (8) mounted around or immediately behind said part of the sensing member (2), said magnet (8) having a shape adapted to the latter and to the shape of the housing (4) in the region of said sensitive face (6).

[0036] In the context of the design and development of the detector (1), it may advantageously be provided that the magnet (8) is configured and has a magnetic field strength sufficient to ensure that at least one ferromagnetic reference piece (PR) is held in position in a region of a determined plane (PD) perpendicular to the direction (D) of said magnetic attraction force (FAM) generated by said magnet (8) and located outside the housing (4), beyond the sensitive face (6).

[0037] In relation to embodiments of the invention illustrated in figures 1, 2, 4 and 5, it may be provided that the protective housing (4) has a cylindrical tubular shape, preferably with an external thread and where appropriate with definition of a detection head (4') of larger diameter housing the detection member (2) and the magnet (8), said magnet (8) having a discoidal or annular shape and the longitudinal axis of the housing (4) being coincident with the direction (D) of said magnetic attraction force (MAF) generated by the magnet (8).

[0038] In relation to the realization of figures 3, the protective housing (4) may have a parallelepiped shape, for example substantially cubic, with a sensitive face (6) of square or rectangular shape, a fixing screw (9) advantageously passing through said housing (4) to ensure its securing and orientation.

[0039] The invention also relates, in connection with an advantageous application of the detector (1), to an industrial workstation (not shown), in particular a welding station, automated or semi-automated, comprising at least one robotic device for picking up, moving and holding, at least temporarily, for example in an indexed position, a ferromagnetic part.

[0040] This workstation is characterized in that the robotic device is provided with at least one detector (1) as described above as a combined gripper and presence detection device for the ferromagnetic part.

[0041] Of course, the invention is not limited to the embodiments described and shown in the accompanying drawings. Modifications remain possible, particularly with regard to the composition of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims

Claims

1. Presence or proximity detector (1) comprising at least one detection member (2), at least one circuit (3) for processing the signals delivered by the latter, also ensuring the power supply or excitation of said member (2), and a protective housing (4) housing said member (2) and said circuit (3) and having a wall (5) defining a sensitive face (6) in relation to the detection member (2), as well as means (7) of electrical connection for said circuit (3), detector (1) characterized in that it also comprises at least one magnet (8), of the permanent or electromagnet type, mounted in the protective housing (4), in the region of the sensitive face (6), the aforementioned member (2) and circuit (3) being selected and / or configured in such a way that the presence or proximity detection function is not disturbed by this magnet (8).

2. Detector according to claim 1, characterized in that it consists of an inductive detector (1) with a detection member (2) of the LC circuit type and a circuit (3) adapted for excitation and processing of the signals, preferably an inductive detector of the “factor 1” type.

3. Detector according to claim 1, characterized in that it consists of a mechanical contact pressure detector (1) with a detection member (2) in the form of a transducer cell and a suitable signal processing circuit (3).

4. Detector according to claims 2 and 3, characterized in that it comprises a hybrid detection member combining the functions of inductive detection, by means of a detection member (2) of the LC circuit type, and mechanical detection by pressure, by means of a detection member (2) in the form of a transducer cell, as well as suitable circuits for excitation and signal processing.

5. Detector according to any one of claims 1 to 4, characterized in that said at least one magnet (8) is arranged in the protective housing (4), preferably in the immediate vicinity of the sensitive detection face (6), so as to generate a magnetic attraction force (FAM) in a direction (D) substantially perpendicular to the plane of said sensitive face (6).

6. Detector according to any one of claims 1 to 5, characterized in that at least a part of the detection member (2) is arranged on the internal side of the wall (5) defining the sensitive face (6) and in that that said detector (1) comprises a magnet (8) mounted around or immediately behind said part of the detection member (2), said magnet (8) having a shape adapted to the latter and to the shape of the housing (4) in the region of said sensitive face (6).

7. Detector according to any one of claims 1 to 6, characterized in that the magnet (8) is configured and has a magnetic field strength sufficient to ensure the holding in position of at least one reference ferromagnetic part (PR) in a region of a determined plane (PD) perpendicular to the direction (D) of said magnetic attraction force (FAM) generated by said magnet (8) and located outside the housing (4), beyond the sensitive face (6).

8. Detector according to any one of claims 1 to 7, characterized in that the protective housing (4) has a cylindrical tubular shape, preferably with an external thread and where appropriate with definition of a detection head (4') of larger diameter housing the detection member (2) and the magnet (8), said magnet (8) having a discoidal or annular shape and the longitudinal axis of the housing (4) being coincident with the direction (D) of said magnetic attraction force (FAM) generated by the magnet (8).

9. Detector according to any one of claims 1 to 7, characterized in that the protective housing (4) has a parallelepiped shape, for example substantially cubic, with a sensitive face (6) of square or rectangular shape, a fixing screw (9) advantageously passing through said housing (4) to ensure its attachment and its orientation.

10. Industrial workstation, in particular welding station, automated or semi-automated, comprising at least one robotic device for picking up, moving and holding, at least temporarily, for example in an indexed position, a ferromagnetic part, workstation characterized in that the robotic device is provided with a detector (1) according to any one of claims 1 to 9 as a combined member for gripping and detecting the presence of the ferromagnetic part.

Images