Sensor positioning device for producing thermal maps of cooking tools

Abstract

Sensor positioning device for producing thermal maps of cooking tools One aspect of the invention relates to a positioning device (1) for sensors (2), in which: the mold (3) has an opening (8) and an internal molding surface (6) where measurement points (7) are located at a distance from each other; the positioning device (1) comprises a rigid three-dimensional assembly (9) formed by a main conduit (10) and a plurality of cable paths (11) extending inside the mold (3), each cable path (11) having: a first end (11a) communicating with the main conduit (10), and a second end (11b) emerging; at least one of the measuring points (7) is located less than a distance (D) from the second end (11b) of a cable tray (11), said distance (D) being such that 0.1 ≤ (D) ≤ 8 centimeters, preferably close to 2 centimeters.Figure to be published with the abstract: Figure 2.

Description

Title of the invention: Device for positioning sensors for producing thermal maps of cooking tools TECHNICAL FIELD OF THE INVENTION

[0001] The technical field of the invention is preferably that of thermal mapping of cooking tools.

[0002] The present invention relates to a device intended to facilitate the positioning of sensors, for example used to produce such thermal maps of cooking tools, and in particular for the thermal mapping of molds intended for the manufacture of plastic or composite parts. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] During the manufacture of plastic or composite parts, resin and a possible reinforcing material are introduced into the cavity of a mold where they are subjected to a rise in temperature aimed at solidifying the resin, for example by polymerization in the case of thermosetting resins. This is called curing these materials and the molds used are also referred to as tools for curing plastic or composite parts.

[0004] This cooking is usually carried out by placing the mold in a heating means, such as an autoclave, an oven or an oven.

[0005] Due to the complex shapes and thickness variations that the molds can have, it is necessary to calibrate the heating means so as to homogenize the internal temperature of the mold cavity.

[0006] In order to carry out this calibration, it is necessary to know the surface temperature at numerous positions located in the mold cavity. This calibration is carried out by positioning numerous temperature sensors, generally thermocouples, against the internal surface of the mold, then carrying out a vacuum heating test of the mold.

[0007] Thermocouples are usually temporarily immobilized at specific points against the internal surface of the mold using adhesive tape, with many pieces of adhesive tape being stuck along the thermocouple cable and against the internal surface of the mold. This operation of positioning the temperature sensors is carried out manually, so it is long and tedious. In addition, there is always a risk that the operator responsible for this task will make a mistake in the position of the measuring head of one or more of these sensors.

[0008] There is therefore a need for a solution allowing the temperature sensors to be installed more simply and more quickly, while avoiding any risk of positioning error against the internal surface of the mold.

[0009] This need is even more felt if the mold must be mapped several times or if the first mapping is to be optimized after one or more manufacturing of composite parts following the thermal mapping, for example when changing the heating means. Summary of the invention

[0010] The invention offers a solution to the problems mentioned above by providing a device for positioning sensors, for example for producing thermal maps of cooking tools, said device comprising a rigid assembly formed from a plurality of cable paths secured to a main conduit in a branched manner, that is to say that from the main conduit, the same cable path can be divided into several branches, which can be divided in turn.

[0011] One aspect of the invention relates to an assembly comprising a mold and a positioning device for sensors, in which: • the mold has an opening and an internal molding surface where measuring points are located at a distance from each other; • the positioning device comprises a rigid three-dimensional assembly formed of a main conduit and a plurality of cable paths extending inside the mold, each cable path having: • a first end communicating with the main conduit, and • a second emerging end; • at least one of the measuring points is located less than a distance D from the second end of a cable tray, said distance D being such that 0.1 < D < 8 centimeters.

[0012] By its branched configuration, the positioning device advantageously makes it possible to pre-position the measuring head of the sensors housed in said positioning device close to the measuring points where it is desired to position a measuring head. Its rigidity advantageously allows it not to be deformed by the weight of the sensors it houses and therefore to maintain this pre-positioning indexing for the measuring head of the sensors. The distance D is advantageously minimal for positioning the second end of a cable tray in the immediate vicinity of a measuring point, but it is nevertheless sufficient to allow the operator to have a length of cable outside the positioning device to be able to position the measuring head of a sensor bearing against the internal molding surface, at a measuring point.

[0013] In addition to the characteristics which have just been mentioned in the preceding paragraph, the assembly according to one aspect of the invention may have one or more complementary characteristics among the following, considered individually or according to all technically possible combinations: • the distance D is such that 0.5 < D < 5 centimeters, preferably such that 1 < D < 3 centimeters and more preferably such that 1.5 < D < 2.5 centimeters. • from the main conduit, at least one cable path divides into several cable paths, which advantageously makes it possible to increase the branching of the positioning device and to provide a second emerging end near a large number of measuring points. • at least one cable tray is assembled or in one piece with the main conduit. • at least part of the main conduit is housed in the opening of the mold, preferably in a sealed manner, which makes it possible, for example, to keep the positioning device in place thanks to the opening of the mold and / or to provide a seal between the main conduit and the opening of the mold. • at least one cable path is in bearing contact against the internal molding surface, which advantageously allows the positioning device to be directly wedged in the mold and thus ensures better pre-positioning indexing for the measuring head of the sensors. • the positioning device comprises at least one stiffener extending between two cable trays or between a cable tray and the main conduit, and connecting them mechanically, which advantageously makes it possible to improve the overall rigidity of the positioning device, for better pre-positioning indexing for the measuring head of the sensors. • the positioning device comprises at least one support piece having a first end assembled or in one piece with a cable tray and a second end in support contact against the internal molding surface, which advantageously makes it possible to wedge the positioning device in the mold. • each cable tray has sides connecting its first end to its second end, and at least one cable tray has one or more openings in at least one of its sides, which advantageously makes it possible to reduce the mass of the positioning device and to provide additional outlet orifices for the sensors within the cable trays, in addition to their second open end. • at least one of the measuring points is located less than a distance D from one of the openings provided in a sidewall, said distance D being such that 0.1 < D < 8 centimeters, which advantageously allows pre-positioning for the measuring head of a sensor while having a sufficient cable length for its installation. at least one opening of a cable tray is equipped with one or more covers, which advantageously make it possible to hold the sensors in the cable tray and to stiffen it at the level of said opening. at least one opening of a cable tray is in the form of a longitudinal insertion slot, which advantageously makes it possible to slide one or more sensors through this slot, for example by temporarily spreading the lips elastically. at least one cover has one or more openings, which advantageously makes it possible to reduce the mass of said cover and to provide additional outlets for the sensors within the cable trays, in addition to their second open end. The mold is a mold for the manufacture of plastic or composite parts. The measuring points are locations where you want to measure a temperature, for example with a thermocouple. The positioning device is mostly made of metal, preferably steel or aluminum. when used, the mold is heated to a maximum heating temperature T, and the positioning device is mainly made of a polymer material whose glass transition temperature is at least 10°C higher than said maximum heating temperature T, which advantageously allows it not to be damaged when the mold is heated, at least part of the positioning device is a product resulting from additive manufacturing, which advantageously allows the manufacture of a positioning device which can have a complex three-dimensional architecture. The positioning device is mainly made of polyetherimide (PEI), polyethylene terephthalate glycol (PETG), polyetherketoneketone (PEKK), acrylonitrile styrene acrylate (ASA) or a mixture of these, which advantageously allows it to be manufactured by additive manufacturing and to retain its rigidity if the mold is heated. each cable tray has a maximum width L such that 3 mm < L < 20 mm, preferably such that 5 mm < L < 15 mm, and more preferably such that 8 mm < L < 12 mm, which advantageously allows for sufficient width to guide sensors, but without weighing down usefully the positioning device. • at least one cable tray has visible markings on one of its sides.

[0014] The invention and its various applications will be better understood upon reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0015] The figures are presented for information purposes only and in no way limit the invention.

[0016] [Fig.l] is a schematic cross-sectional view of a mold equipped with a positioning device according to the invention into which sensors are introduced.

[0017] [Fig.2] is a schematic view in longitudinal section of a mold equipped with a positioning device according to the invention into which sensors are introduced.

[0018] [Fig.3] is an enlarged view of the circled portion in [Fig.2].

[0019] [Fig.4]-[Fig.l2] illustrate different variants of cable trays given for the purpose of of examples. DETAILED DESCRIPTION

[0020] Unless otherwise specified, the same element appearing in different figures has a single reference.

[0021] As shown in [Fig.l] and [Fig.2], the positioning device 1 of the invention is provided for housing sensors 2 in a mold 3.

[0022] The mold 3 is for example a mold 3 for the manufacture of plastic or composite parts. It may comprise several parts 3a, 3b.

[0023] The sensors 2 each comprise a measuring head 4 and a cable 5 connected to the measuring head 4 and the free end of which is intended to be connected to an electrical or electronic device 13. These sensors 2 may for example be thermocouples, the cable 5 then usually being referred to as an angel wire due to its very small diameter.

[0024] The positioning device 1 of the invention may be provided for different types of sensors and / or for identical sensors for the same type of measurement. The measurements may, for example, be temperature, pressure, or any other measurement, in particular physical.

[0025] The positioning device 1 of the invention has the purpose of guiding the cable 5 of the sensors 2 to certain fixed and defined positions inside the mold 3, located on the internal molding surface 6 at a distance from each other and where it is desired to carry out a measurement using said sensors 2. These positions are designated as measurement points 7.

[0026] By measuring point 7, we therefore mean a location situated on the internal surface 6 of the mold 3 where we wish to measure a physical parameter using a sensor 2.

[0027] According to a preferred embodiment of the invention, the physical parameter is a temperature value, and the sensor 2 is a thermocouple. The invention can however be easily adapted to other types of physical parameters and sensors 2. The positioning device 1 of the invention can thus be used to produce thermal maps of cooking tools, but also any other type of mapping of a mold 3 produced by placing sensors 2 inside it.

[0028] The positioning device 1 of the invention has orifices 8 allowing the measuring head 4 and a part of the cable 5 of each sensor 2 to protrude outside the positioning device 1 into the mold 3, so as to allow an operator to be able to position the measuring head 4 of a sensor 2 on each measuring point 7, against the internal surface 6 of the mold 3.

[0029] The positioning device 1 comprises a rigid three-dimensional assembly 9, designed to at least partially house the cable 5 of each sensor 2, and formed of a main conduit 10 and a plurality of cable paths 11.

[0030] By rigid is meant that the positioning device 1 of the invention has sufficient rigidity to keep its shape when it guides sensors 2 and houses the cables 5 of said sensors 2, even when the mold 3 is subjected to heating, for example for the baking of a part made of plastic or composite material.

[0031] Optionally, this rigidity can also allow the cable trays 11 to be elastically deformed temporarily to introduce the cables 5 of the sensors 2, for example when the cable trays 11 have an introduction slot 18 for said cables 5 as will be described later.

[0032] Each cable tray 11 has a first end 11a communicating with the main conduit 10 and at least one second end 11b opening out which can constitute one of the aforementioned orifices 8. Each cable tray 11 has sides 14 connecting its first end 11a to its second end 11b. A cable tray 11 can have several opening out ends.

[0033] According to a preferred embodiment of the invention, from the main conduit 10, at least one cable tray 11 divides into several secondary cable trays 11, these secondary cable trays 11 being able in turn to divide into several tertiary cable trays 11, etc. When a cable tray 11 divides into several cable trays 11, the latter preferably have a width less than that of the cable tray 11 from which they originate. Thus, the positioning device 1 is branched, somewhat like a root system, to provide a second end 11b near a large number of measuring points 7.

[0034] A cable tray 11 can be assembled with the main conduit 10, by any known assembly system. Being removable, the cable tray 11 can be dismantled, for example in order to reduce the size of the positioning device 1 for its storage before use.

[0035] A cable tray 11 can also be made in one piece with the main conduit 10, which avoids any loss of time and any risk of positioning error linked to assembly.

[0036] In use, the positioning device 1 is housed inside the mold 3 so that most of the measuring points 7, preferably all of them, are located close to an orifice 8 of the positioning device 1, at a distance D for example between 0.1 and 8 centimeters.

[0037] According to a preferred embodiment of the invention, the distance D is such that 0.5 < D < 5 centimeters, preferably such that 1 < D < 3 centimeters and more preferably such that 1.5 < D < 2.5 centimeters. Indeed, the preferred distance for D is approximately 2 centimeters.

[0038] It will be noted that this distance D is measured from the center of an orifice 8 to the center of the measuring point 7 associated with it.

[0039] For this installation, the mold 3 is opened, then the positioning device 1 is housed inside it before closing the mold 3. At least a part of the main conduit 10 is then housed in an opening 12 of the mold 3, preferably in a sealed manner. This opening 12 may for example be a pre-existing opening 12 in the mold 3, for example provided for an injection of polymer inside it, or be an opening 12 only provided for the passage of the main conduit 10. It is indeed necessary to be able to connect the free end of the sensors 2 to an electrical or electronic device 13 located outside the mold 3 in order to receive and process the measurements obtained by them.

[0040] In order for the positioning device 1 to carry out pre-positioning indexing for the measuring head 4 of the sensors 2, it is preferable for it to be wedged inside the mold 3, bearing against the internal surface 6 thereof.

[0041] Thus, a cable tray 11 can be in bearing contact against the internal surface 6, preferably over a majority of its length, the cable tray 11 then being able to have a side 14 substantially matching the shape of the internal surface 6 against which it is in bearing.

[0042] For this purpose, the positioning device 1 may also comprise support pieces 15, each having a first end 15a assembled or in one piece with another element of the positioning device 1, for example a cable tray 11 or a stiffener 16 (see below), and a second end 15b provided to also be in support contact against the internal surface 6.

[0043] In order to prevent the positioning device 1 from deforming, it may comprise stiffeners 16, each of which extends between two elements of the positioning device 1 to mechanically connect them, for example the cable trays 11, the main conduit 10 and the support pieces 15 if present. These stiffeners 16 can be assembled or in one piece with these elements.

[0044] Cable trays 11 may have one or more openings 17 in at least one of their sides 14 (see [Fig.5], [Fig.7], [Fig.8], [Fig.9], [Fig. 12]).

[0045] Some of these openings 17 may constitute one of the orifices 8 described previously and intended to be located at a distance D for example between 0.1 and 8 centimeters from a measurement point 7.

[0046] It will be noted that this distance D is measured from the center of an opening 17 to the center of the measuring point 7 associated with it.

[0047] These openings 17 can also serve to reduce the mass of the cable trays 11, and / or to allow the introduction of the cables 5 into the cable trays 11.

[0048] The cable trays 11 can take several forms.

[0049] Generally speaking, a cable tray 11 within the meaning of the invention is a device allowing the passage of one or more cables 5, it is therefore a hollow device in which one or more cables 5 can be put in place and removed manually, in particular for the purpose of guiding the routing of said cables 5 along a path delimited by internal walls of said cable tray 11.

[0050] Thus, the cable trays 11 can for example be in the form of profiles, electrical ducts (see [Fig.4]), rigid sheaths, supports equipped with flexible tabs (see [Fig.12]), grid structures, honeycomb structures, mesh structures (see [Fig.9]), openwork structures (see [Fig.8]), etc. They can have a circular, oval, square, rectangular, triangular, polygonal or other shaped section.

[0051] In order to allow the introduction of a cable through one of their sides, in addition to the openings 17 which may constitute orifices 8 within the meaning of the invention, the cable trays 11 may for example also have a longitudinal slot 18 (see [Fig.10] and [Fig.11]), an open face equipped with one or more covers 20, removable (see [Fig.4], [Fig.5], [Fig.7] and [Fig.8]) or pivotally mounted (see [Fig.6]), or any other cable retaining element which may for example be found in commercially available cable trays 11.

[0052] The main conduit 10 may have the same characteristics as the cable trays 11. It is preferably in the form of a hollow piece of revolution open at its two ends.

[0053] The positioning device 1 can be made mainly of metal, preferably steel or aluminum.

[0054] It can also be made mainly of polymer, preferably of a material thermoplastic whose glass transition temperature is at least 10°C higher than said maximum heating temperature T to which the mold 3 is heated when it is used for molding or for carrying out heating tests.

[0055] It can be manufactured entirely or partially by additive manufacturing. In this case, it is preferably manufactured mainly from polyetherimide (PEI), polyethylene terephthalate glycol (PETG), polyetherketoneketone (PEKK), acrylonitrile styrene acrylate (ASA) or a mixture of these.

[0056] Generally speaking, the material constituting the positioning device 1 can be chosen according to the heating temperature range of the mold 3 in which it will be used.

[0057] Similarly, the overall dimensions of the positioning device 1 depend on the dimensions of the mold 3 in which it must be positioned and the location of the different measuring points 7. It is therefore not possible to give here a preferred length for the cable trays 11.

[0058] In the case where certain measuring points 7 are difficult to access, the positioning device 1 can be adapted accordingly, or else several positioning devices 1 can be used. In the latter case, the shape of their respective main conduit 10 can for example be adapted so that they can be housed in the same opening 12 of the mold 3.

[0059] The width of the cable trays 11 is preferably chosen so that the cable trays 11 are sufficiently rigid to guide the cables 5 and have an internal volume sufficient to accommodate said cables 5.

[0060] According to a preferred embodiment of the invention, each cable tray 11 has a maximum width L such that 3 mm < L < 20 mm, preferably such that 5 mm < L < 15 mm, and more preferably such that 8 mm < L < 12 mm.

[0061] According to another preferred embodiment of the invention, at least one cable tray 11 has a visible marking on one of its sides 14 (not shown). This marking can be indicated directly on the cable tray 11 by adding a reference and / or directly manufactured in the structure of the cable tray 11 cable. The marking can be digital or by any other means facilitating the identification and more precise positioning of the cable trays including sensors. Such a marking can be produced in relief, in hollow, in color or in any other way allowing it to be distinguished on said cable tray 11. This marking can for example make it possible to identify the position of a sensor 2, a cable 5 or a measuring point 7, or to identify such a sensor 2, cable 5 or measuring point 7.

[0062] The method of using the positioning device 1 is very simple and very quick to implement.

[0063] Firstly, the mold 3 must be opened and the positioning device introduced into it. operation 1, ensuring that each orifice 8 of the positioning device 1 intended to be positioned near a measuring point 7 is correctly positioned where it must be. This positioning can be considerably facilitated if the positioning device 1 generally adopts an external shape corresponding to the internal shape of the mold, with numerous support zones for wedging the positioning device 1 against the internal surface 6 of the mold 3. The main conduit 10 is preferably positioned at an opening 12 of the mold 3.

[0064] In a second step, the sensors 2 are housed in the cable trays 11 and the main conduit 10. For this installation, the sensors 2 can be slid into the cable trays 11 and the main conduit 10, for example through the main conduit 10 or the second end 11b of the cable trays 11. However, in particular because of the very great flexibility that the cables 5 of these sensors 2 can have, it is preferred and generally easier to introduce them directly into the cable trays 11, for example through an open face or an insertion slot provided longitudinally in the cable trays 11. In the case where covers 20 are provided for the cable trays 11, they must then be put in place.

[0065] In a third step, the measuring head 4 of each sensor 2 can be immobilized at a measuring point 7, for example by fixing a piece of adhesive tape 21 on the cable 5 in the immediate vicinity of said measuring head 4 (see [Fig. 3].

[0066] Finally, in a final step, it is sufficient to close the mold 3 and connect each sensor 2 to an electrical or electronic device 13. The mold 3 is then ready to be mapped.

[0067] Although described through a certain number of examples, variants and embodiments, the positioning device 1 according to the invention comprises various variants, modifications and improvements which will be obvious to those skilled in the art, it being understood that these variants, modifications and improvements are part of the scope of the invention.

Claims

Claims

1. Assembly comprising a mold (3), characterized in that it further comprises a positioning device (1) for sensors (2), in which: - the mold (3) has an opening (12) and an internal molding surface (6) where measuring points (7) are located at a distance from each other; - the positioning device (1) comprises a rigid three-dimensional assembly (9) formed by a main conduit (10) and a plurality of cable trays (11) extending inside the mold (3), each cable tray (11) having: • a first end (11a) communicating with the main conduit (10), and • a second end (11b) emerging; - at least one of the measuring points (7) is located at a distance (D) from the second end (11b) of a cable tray (11), said distance (D) being such that 0.1 < (D) < 8 centimeters.

2. Assembly according to claim 1, characterized in that the distance (D) is such that 0.5 < (D) < 5 centimeters, preferably such that 1 < (D) < 3 centimeters and more preferably such that 1.5 < (D) < 2.5 centimeters.

3. Assembly according to claim 1 or 2, characterized in that, from the main conduit (10), at least one cable tray (11) divides into several cable trays (11).

4. Assembly according to any one of the preceding claims, characterized in that at least one cable tray (11) is assembled or in one piece with the main conduit (10).

5. Assembly according to any one of the preceding claims, characterized in that at least part of the main conduit (10) is housed in the opening (12) of the mold (3), preferably in a sealed manner.

6. Assembly according to any one of the preceding claims, characterized in that at least one cable tray (11) is in bearing contact against the internal molding surface (6).

7. Assembly according to any one of the preceding claims, characterized in that the positioning device (1) comprises at least one stiffener (16) extending between two cable trays (11) or between a cable tray (11) and the main conduit (10), and connecting them mechanically.

8. Assembly according to any one of the preceding claims, characterized in that the positioning device (1) comprises at least one support piece (15) having a first end (15a) assembled or in one piece with a cable tray (11) and a second end (15b) in support contact against the internal molding surface (6).

9. Assembly according to any one of the preceding claims, characterized in that each cable tray (11) has sides (14) connecting its first end (11a) to its second end (11b), and in that at least one cable tray (11) has one or more openings (17) in at least one of its sides (14).

10. Assembly according to any one of the preceding claims, characterized in that each cable tray (11) has a maximum width (L) such that 3 mm < (L) < 20 mm, preferably such that 5 mm < (L) < 15 mm, and more preferably such that 8 mm < (L) < 12 mm.

Images