Abstract: A light receiving section 27b receives a measurement beam, which is cast from a light projection section 27a and partially blocked by cream solder 19 scraped up by a squeegee 16, whereby a sensor 27 measures a one-dimensional size of a predetermined region of a cross sectional profile of the cream solder 19 as a cross sectional paste length and takes the cross sectional paste length as an index for an amount of residual cream solder 19. The amount of residual cream solder 19 can be numerically grasped at all times, so that versatility and accuracy in detecting the amount of residual cream solder 19 can be assured.

Abstract: A method of partially imaging a substrate, for example glass, with a print pattern comprising layers of ceramic ink in substantially exact registration. The method relies on a mask ink layer defining the print pattern and differential thermal expulsion of ceramic ink medium during a heat fusing process between the areas outside the print pattern and within the print pattern. This results in pigment and glass frit forming a durable image material adhered to the substrate within the print pattern and non-durable material outside the print pattern, enabling its removal outside the print pattern to leave the desired layers of ceramic ink within the print pattern in substantially exact registration.

Abstract: The present invention describes a single-layer printing method of a wrapper for smoking articles, so as to obtain a wrapper for smoking articles with low propensity to ignition using the flexographic technique, characterized in that (1) the printing is carried out by means of a central drum flexographic printing machine using a single printing unit, (2) said unit has an anilox with a capacity of between 10 and 40 cm3/m2 and a printing cylinder equipped with a printing form selected from a stencil plate plus an adhesive, and a sleeve, and (3) in that an ink is used that comprises at least one film-forming substance and a mineral filler. The present invention also relates to the wrapper that can be obtained by this method and to the smoking article that includes said wrapper.

Abstract: In a screen printing that shifts squeegees in a horizontal direction while abutting the squeegees against a mask, and slides the squeegees on the mask, and scrapes up the paste on the mask so that opening portions are filled with the paste to transfer the paste onto the substrate, a larger amount of paste Ps is supplied to regions in which the paste is scraped up by the end portions of the squeegee than a region in which the paste is scraped up by a center portion of the squeegee on the mask.

Abstract: The invention relates to a method for printing objects, comprising the step of application of a printing ink by means of screen printing, wherein the printing ink comprises a polyisocyanate A) and/or a polyisocyanate prepolymer B), an at least difunctional compound C) which is reactive towards isocyanate groups and furthermore a catalyst D) which cap be activated by increasing the temperature. It also relates to the use of a corresponding reaction, mixture as a printing ink in screen printing processes and to an electromechanical converter having a polymer layer produced, by a method according to the invention.

Abstract: A screen-printing panel comprising a locking strip sewn to screen-printing mesh is described. The mesh along an edge of the panel is folded around the locking strip and secured using a line of stitching. A gap between the end of the locking strip and the edge of the mesh contributes to corner softening. Another gap between the end of the stitching and the end of the locking strip also contributes to corner softening. Locking strips have various cross sections including rectangular, triangular, and complex curves. Two colors of thread may be used to aid in orienting the panel. An adhesive may be used to hold the mesh to the locking strip for convenience during handling and sewing.

Abstract: A screen printing apparatus including two screen printers, each including a substrate introduction portion by which a substrate is introduced from an upstream side of a component mounting line, a printing portion which performs a screen printing to the introduced substrate, a substrate discharge portion by which the substrate is discharged to a downstream side, and a substrate moving stage which receives the substrate to position the substrate with respect to the printing portion and to move the substrate to the substrate discharge portion. The two substrate introduction portions, the two printing portions, and the two substrate discharge portions are arranged symmetrically to each other with respect to a perpendicular symmetrical plane extending in a transportation direction of the substrate in the component mounting line, respectively. Each printing portion is provided at a position further from the perpendicular symmetrical plane than the substrate discharge portion.

Abstract: A screen printing line with higher utility is provided. In a screen printing line including a plurality of screen printing machines and a plurality of shuttle conveyors each provided between any adjacent two of the plurality of screen printing machines, each of the screen printing machines includes: a main body; a front conveyor having a substrate support device; a rear conveyor configured to allow passage of a circuit substrate; a printing device configured to carry out screen printing on the circuit substrate supported by the substrate support device. Also, each of the plurality of shuttle conveyors includes a movable conveyor movable between a position continuous to the front conveyor and a position continuous to the rear conveyor.

Abstract: A screen printing apparatus includes a printing execution unit that performs screen printing on a substrate. At least one substrate support table that is provided movably along a specific direction orthogonal to the conveying direction. A table drive mechanism that moves the substrate support table at least between substrate entry and exit positions along a specific direction. The substrate entry and exit positions are set asymmetrically with respect to the specific direction. A printing execution unit drive mechanism is provided to drive the printing execution unit along the specific direction. A control unit is provided to control the printing execution unit drive mechanism so that the printing execution unit is driven to set the printing position on a substrate conveying path needed for the substrate support table to move from the substrate entry to the substrate exit.

Abstract: A holding mechanism 40 is made up of a shaft support 44 that is provided while joined to a joint and that has a vertically-oriented pivot 44a, a shaft member 45 that horizontally extends from the shaft support 44 and that is turnable around the pivot 44a, and a fitting section 36 that is formed in a squeegee unit 16 and to which the shaft member 45 is removably fitted. Thereby, the entirety of the squeegee unit 16 becomes removably attachable by only moving the squeegee unit 16 in a horizontal direction.

Abstract: A method of making a bas relief from a two-dimensional image includes converting a two-dimensional image to a gray-scale image that comprises a plurality of shades of gray. Each shade of gray corresponds to a respective elevation of a three dimensional representation of the two-dimensional image. The gray-scale image is then converted to a half-tone bitmap image that is etched onto a print screen stencil. Meltable powder is forced through the open mesh areas of the print screen stencil to form a three-dimensional pattern of powder on a substrate positioned beneath the print screen stencil in spaced-apart relationship therewith. The three-dimensional pattern of the powder corresponds to the three-dimensional representation of the two-dimensional image. The three-dimensional pattern of powder is then heated to fuse the powder together to form a bas relief.

Abstract: Ultraviolet light-curable deposits are printed onto a substrate in a predetermined pattern to make tactile marks (e.g. Braille-like resin dots) for use by people with impaired vision to, for example, recognize the denominations of banknotes. The deposit demonstrates high adhesion due to: (1) presence of 20-80% (wt.) of a low viscosity acrylate component to provide a substrate-penetrating property; and, (2) 2-30% (wt.) of an adhesion-promoting acid acrylate. The deposit material further includes 1-30% (wt.) of urethane acrylate, 1-30% by weight of reactive diluent, photoinitiator and 1-10% (wt.) of rheological adsorbing additive. Optimally, the adhesion promoter is added after the other components have been mixed with the rheological additive. The printing step may be followed by heating before the curing step to increase penetration of the ink into the substrate. The deposit may comprise a taggant for use as a security feature.

Abstract: A screen printing apparatus includes: a main squeegee that includes a pair of end portions in a width direction and prints, by sliding in a direction orthogonal to the width direction on an upper surface of a screen that is supplied with a paste-like material and on which a hole is formed, the paste-like material on an upper surface of a printing object provided on a lower surface side of the screen via the hole; and a pair of auxiliary squeegees each including a first end portion provided more on an outer side than the end portion in the width direction and a second end portion provided more on an inner side than the end portion in the width direction, the pair of auxiliary squeegees being tilted a predetermined angle with respect to the main squeegee on a rear side of the main squeegee in the sliding direction.

Abstract: Screen printing system with positional alignment for aligning a substrate with a screen mask. The substrate and the screen mask have two registration holes for facilitating the positional alignment. The positional alignment method includes calculating alignment values for correcting the position of the substrate based on the determined offsets between the registration holes of the substrate and the screen mask. The position of the substrate is corrected based on the calculated alignment values so that registration holes of the substrate are vertically aligned with the registration holes of the screen mask.

Abstract: A system or machine is disclosed which takes pre-stretched emulsion coated screens, digitally prints thereon and exposes them before further processing and use in a screen printing machine.

Abstract: The screen printing apparatus includes two screen printers 11A and 11B each including a substrate introduction portion 12 by which a substrate 4 is introduced from the upstream side of the component mounting line 3, a printing portion 13 which performs a screen printing to the introduced substrate 4, a substrate discharge portion 14 by which the substrate 4 subjected to the screen printing is discharged to the downstream side, and a substrate moving stage 15 which receives the introduced substrate 4 so as to position the substrate 4 with respect to the printing portion 13 and to move the substrate 4 subjected to the screen printing to the substrate discharge portion 14. The two substrate introduction portions 12, the two printing portions 13, and the two substrate discharge portions 14 are arranged symmetrically to each other with respect to a perpendicular symmetrical plane S extending in a transportation direction of the substrate 4 in the component mounting line 3, respectively.

Abstract: Prior to a mark imaging process executed for the purpose of detecting a position of recognition marks for positioning the substrate and the mask, an optical axis calibration processing process of detecting a horizontal relative position between imaging optical axes, and a surface correction data creation processing process of detecting a local positional deviation of the imaging optical axes, which is caused by the travel of the imaging unit, are executed. Before starting production, a production pre-start precision evaluation process for evaluating a substrate positioning precision is executed by using a verification substrate and a verification mask, and after starting the production, a production post-start precision evaluation process for evaluating a substrate positioning precision after starting the production is executed by using a commercial production substrate and a commercial production mask.

Abstract: A method is provided for applying a superabsorbent polymer to a fibrous sheet material. The fibrous sheet material may be a nonwoven material or a tissue paper. The method includes applying a crosslinkable polymeric dispersion or solution onto the fibrous sheet material by printing technique and in a separate step applying a crosslinking agent onto the fibrous sheet material by printing technique, wherein said crosslinking agent accomplishes crosslinking of the crosslinkable polymer to form a superabsorbent material. A tissue or nonwoven product-includes at least two plies that are bonded together, wherein a crosslinked superabsorbent material is applied in a printed pattern between the plies, said tissue or nonwoven product having a DIN54540 Water Absorption between 15 and 100 g/g.

Abstract: Prior to a mark imaging process executed for the purpose of detecting a position of recognition marks for positioning the substrate and the mask, an optical axis calibration processing process of detecting a horizontal relative position between imaging optical axes, and a surface correction data creation processing process of detecting a local positional deviation of the imaging optical axes, which is caused by the travel of the imaging unit, are executed. Before starting production, a production pre-start precision evaluation process for evaluating a substrate positioning precision is executed by using a verification substrate and a verification mask, and after starting the production, a production post-start precision evaluation process for evaluating a substrate positioning precision after starting the production is executed by using a commercial production substrate and a commercial production mask.

Abstract: Provided in various embodiments are high viscosity, shear-thinning silicone compositions that can be pattern coated directly onto a substrate. The silicone compositions may be prepared by mixing at least one organopolysiloxane, at least one SiH-containing organopolysiloxane, at least one emulsifying agent, a hydrosilyation catalyst and water. The silicone compositions may be applied on a substrate for use in medical devices or wound dressings.

Abstract: The device includes a drop dispenser orifice formed in a dispenser end, and a mechanism for visually locating the orifice, by forming a demarcation zone having a color that contrasts strongly with other portions of the dispenser end.

Abstract: A screen printing mesh including a plurality of octagonal first openings and a plurality of polygonal second openings, each of the second openings being disposed between the first openings, wherein an inner angle between a first line segment of each of the second openings and an adjacent second line segment is 90 degrees or greater.

Abstract: Method for printing on a wafer (1) by screen-printing, characterized in that it comprises the following steps: producing at least two first test-patterns (5a-5d) on the surface (4) of the wafer (1); printing at least four second test-patterns (6a-6d), distinct from the at least two first test-patterns (5a-5d), during printing on the surface (4) of the wafer (1) by screen-printing; measuring the actual distance obtained on the surface (4) of the wafer (1) between the first test-patterns (5a-5d) and the second test-patterns (6a-6d); comparing this actual distance with a theoretical distance in order to deduce therefrom the offset of the screen-printing screen (25) of the printing.

Abstract: A screen printing apparatus in which two printing units are provided in a production line which transports boards from a single board exit position set on a downstream side in a conveyance direction. One printing unit being disposed is available for set-up tasks while the other printing unit is working. Since set-up tasks can be conducted in one printing unit while the other printing unit is working, then it is possible to improve through-put dramatically even in cases where small-volume diverse-component production is carried out in a single lane.

Abstract: Stencil for a screen-printing system, comprising slits (22, 23) in a central printing zone (13), forming a pattern to be printed, characterized in that it comprises one or more apertures (32) in a peripheral deforming zone (14), which apertures are intended to cause this peripheral deforming zone (14) to deform under the effect of a stress applied to the stencil while reducing deformation of the central printing one (13).

Abstract: It is an objective to provide a screen print system and a method for cleaning a mask of the screen print system that enable sufficient cleaning of the mask used for subjecting a cavity substrate to screen printing. A mask contact area R of a paper member 42 is brought into contact with a lower surface of one of convex portions 13t of a first mask 13a, thereby removing paste Pst adhering to the lower surface. Subsequently, the paper member 42 is winded up before the paper member 42 contacts the next convex portion 13t to be subjected to removal of the paste Pst, thereby updating the mask contact area R.

Abstract: The invention describes an apparatus for producing a multicoloured design on a surface of a beverage or a food item. The apparatus comprises a stencil mount (110) comprising a first locating member (118), and a stencil (120) defining a horizontal plane and comprising a second locating member (118). The stencil is adapted to rest upon the stencil mount in such a way that the first locating member engages with the second locating member, thereby inhibiting or preventing rotation of the stencil within the horizontal plane and relative to the stencil mount. It is further described a method of producing a design on a surface of a beverage or a food item.

Abstract: A screen printing apparatus and method for printing deposits of a print medium on workpieces, the apparatus comprising: a frame support unit for supporting a printing screen unit which comprises a screen sheet which includes at least first and second patterns of print apertures; a workpiece support unit; a print head unit; and at least one screen cleaning unit; wherein the at least one screen cleaning unit and the print head unit are operated in parallel, whereby, when the printing screen unit is in the first printing position, the at least one screen cleaning unit cleans the underside of the screen sheet at a location corresponding to one of the first and second sets of print apertures and the print head unit prints print medium onto workpieces through the other of the first and second sets of print apertures.

Abstract: Device and process for producing indicia comprising magnetically oriented magnetic or magnetizable particles in ink or coating composition on a sheet of substrate material. Device includes a flat-bed screen-printing unit having a flat printing screen and a printing platen for receiving a sheet. Printing platen has an upper surface facing the printing screen and a first direction along its upper surface along which said sheet is unloadable, and a magnetic orienting unit having multiple magnet assemblies. Magnetic orienting unit is disposed below upper surface of the printing platen, the multiple magnet assemblies are disposed along first direction, and all of the magnet assemblies are concomitantly movable from a first position away from the upper surface of the printing platen to a second position close to the upper surface of the printing platen. The magnetic orienting unit having one or more magnet assemblies is usable as a stand-alone flat-bed magnetization device.

Abstract: The method for screen printing improves accuracy during a plurality of screen printing steps. After a first layer and an alignment mark are printed on a workpiece, the alignment mark is imaged by a camera so that the alignment mark is stored as image data in an image processing device adapted to deliver reference data for subsequent printing, and the image data is used to renew the reference data in the image processing device.

Abstract: The Automated Cutting System for Customized Field Stencils (“ACSCFS”) is a device designed to implement an automated field stencil creation process. The ACSCFS is comprised of a computer system and an automated cutting table, wherein said automated cutting table is further comprised of a cutting surface, an automated means for placing sheet material onto said cutting surface, and an automated cutting implement. The computer analyzes a color logo image and translates it into a line drawing. The drawing is then scaled, and guideline aperture locations are placed along each line. The computer then transmits instructions to the automated cutting table, directing the creation of a field stencil with a dotted guideline hole pattern. Such field stencils allow for the reproduction of multi-color logos using a single stencil.

Abstract: The inside of a housing of a printer device is cooled by the air from a ventilation port and, consequently, the temperature of solder SP on a mask surface supported by a mask holding frame inside the housing can be kept low. Moreover, provided is a mask cover for blocking the air flow from the ventilation port toward the mask, and the drying of the solder SP caused by the wind from the ventilation port is thereby inhibited as a result of the wind from the ventilation port not coming into contact with the solder SP on the mask surface. In this way, the solder SP is cooled while inhibiting the drying of the solder SP and, consequently, it is possible to appropriately inhibit the change in viscosity of the solder SP, and favorable printing can be realized.

Abstract: A method of screen printing on low temperature co-fired ceramic (LTCC) is disclosed that comprises the steps of (i) aligning tape position on the printer table of a screen printer machine for precisely positioning the tape relative to the screen mesh of the screen having a plurality of pattern openings; (ii) adjusting screen printing parameter for setting a printing condition, wherein the squeegee speed is adjusted to 50-100 mm/s; squeegee pressure is 0.05-0.wopa15 MPa; and a gap between the screen and the tape is 0.8-1.0 mm; and (iii) optimizing the screen mesh parameter with stainless steel screen mesh, wherein the screen mesh of the screen is optimized at mesh tension of 22-28 N/cm; mesh angle of 22.5°; thickness of an emulsion of 0.044 mm; mesh wire diameter of 0.028 mm; and screen mesh count of 325 apertures per inch.

Abstract: In screen printing on such printing targets as an upper surface of a substrate and a bottom surface of a recess portion which is opened to the upper surface, there are provided a screen printing apparatus and a screen printing method by which printing work can be executed with good efficiency while ensuring a good printing quality.

Abstract: A system and method of generating a combined media print receives image data representing an original image at a computer system having at least a non-transitory storage medium and a hardware processor communicatively connected thereto. A quantization algorithm is executed by the hardware processor of the computer system to produce quantized image data from the received image data. Using the quantized image data, the system creates a printing screen having printed thereon a rendering of the quantized image data. The printing screen is aligned on top of a physical substrate having the original image printed or rendered thereon. One or more inks are then applied to the printing screen and, are overlaid onto portions of the original image printed or rendered onto the physical substrate.

Abstract: Screen-printing system comprising a metal stencil (12), and a cloth (15) fixed to the entire periphery of said metal stencil (12) to form a trampoline assembly, characterized in that the cloth (15) fixed to the metal stencil (12) has at least one free end, in order to decrease or prevent deformation under the effect of a doctor blade (20).

Abstract: Disclosed is a method of manufacturing a circuit board, which includes a stand-by process setting a screen printing plate so as to be opposed with a base, where the screen printing plate has a line pattern formed therethrough, and the line pattern is configured by a plurality of dot-like through-holes discretely pierced and arrayed in a single line; a coating process coating an ink which contains a water-dispersed electroconductive paste onto the surface of the screen printing plate; and an ejection process ejecting ink dots through the dot-like through-holes onto the surface of the base, by pressing the screen printing plate into the base under sliding contact of a squeegee with the surface of the screen printing plate, and allowing the ink dots ejected out from the adjacent through-holes to fuse on the surface of the base, to thereby form a linear ink puddle.

Abstract: A screen printing device and screen printing method in which, in screen printing which is to be applied to a cavity circuit board configured by bonding board members together, printing misalignment hardly occurs. A mask member has a cavity-portion corresponding mask region MRC where a mask pattern MPC corresponding to cavity-portion electrode patterns is formed on the bottom faces of fitting portions to be fitted into cavity portions CV; and a flat-portion corresponding mask region MRF where a mask pattern MPF corresponding to flat-portion electrode patterns is formed as separate regions. Positioning between the cavity-portion corresponding mask region MRC and the cavity-portion electrode patterns is performed, and screen printing is applied. Positioning between the flat-portion corresponding mask region MRF and the flat-portion electrode patterns is performed, and screen printing is applied.

Abstract: Stencil for a screen-printing system, comprising slits (22, 23) in a central printing zone (13), forming a pattern to be printed, characterized in that it comprises one or more apertures (32) in a peripheral deforming zone (14), which apertures are intended to cause this peripheral deforming zone (14) to deform under the effect of a stress applied to the stencil while reducing deformation of the central printing one (13).

Abstract: In a rotary stencil printing press including a rotary screen cylinder which supports a screen printing form and is supported rotatably, and a squeegee which is located within the rotary screen cylinder and, when printing is done, contacts an inner peripheral surface of the screen printing form to transfer ink stored within the rotary screen cylinder to a web via holes of the screen printing form and, when printing is stopped, leaves the inner peripheral surface of the screen printing form, throw-on and throw-off of the squeegee with respect to the inner peripheral surface of the screen printing form, and adjustment of the position of the throw-on are performed by motors.

Abstract: The present invention provides a screen printing apparatus and screen printing method which, in screen printing that is to be performed on the upper surface of a circuit board, and the bottom surfaces of recess openings in the upper surface, can efficiently perform a printing work while ensuring an excellent printing quality. In a screen printing apparatus which prints a paste for bonding an electronic component on an upper surface and a bottom-surface of a recess, a printing apparatus 2(1) and a printing apparatus 2(2) which sequentially 10 print the paste in two steps on the circuit board are placed in series. The printing apparatus 2(1) on the upstream side includes a bottom-surface printing mask which is provided in correspondence with the bottom surface of the recess, and a closed squeegee mechanism 36A which butts against and slides over an upper surface of the bottom-surface printing mask to 15 pressurize and supply the paste.

Abstract: Disclosed is a conductive composition which can be used to form an aqueous conductive ink with increased conductivity. The aqueous conductive composition contains conductive particles, preferably silver, an anionic wetting agent and a styrene-acrylic copolymer. The composition is highly conductive and requires reduced drying energy. In addition, it may be applied to low cost substrates by high speed printing processes.

Abstract: A printing operation is repeatedly performed with respect to one substrate 2, the printing operation including the step of loading the substrate 2 (the step ST1), then contacting an upper surface of the substrate 2 with a mask 13 (the step ST4), reciprocating a squeegeeing operation to slide squeegees 33b on the mask 13 in contact with the substrate 2 to transfer a paste Pt on the mask 13 to the substrate 2 (the step ST7 and the step ST8), separating the substrate 2 from the mask 13 for a snap off (the step ST9), and while unloading the substrate 2 (the step ST11), performing mask cleaning to remove the paste Pt that is adhered to a lower surface of the mask 13 (the step ST12).

Abstract: There is provided a screen printing apparatus and a screen printing method which can implement printing work with good efficiency while securing a good printing quality in screen printing intended for an upper surface of a substrate and a bottom surface of a recess portion which is opened in the upper surface.

Abstract: A method of producing a reflection transfer for transferring a motif onto a substrate includes providing an adhesive-repellent base medium, applying a transfer adhesive to the base medium, creating a colored print image by offset printing or digital printing, and applying at least one reflection layer which contains a multiplicity of reflection particles.

Abstract: The present invention relates to a self-aligning stencil device for producing a multi-color composite image on a target surface. The self-aligning stencil device includes a central panel and a plurality of stencil panels foldably connected to the central panel. The central panel includes a solid region and a cut-out region. The solid region of the central panel includes a front surface and a back surface, and is defined by an outer border of the central panel and an inner border of the central panel. The cut-out region is vacant space that is defined by the inner border of the central panel. Each stencil panel has its own distinct stencil pattern and is foldably connected to a different corresponding portion of the outer border of the central panel, thereby forming a connection fold between each stencil panel and its corresponding portion of the outer border of the central panel.

Abstract: A screen printing apparatus includes a screen moving mechanism and a controller. The screen moving mechanism is configured to move a screen including a patterned hole, the patterned hole being used for printing a paste-like material on a printing substrate. The controller is configured to control the screen moving mechanism to move the screen to a position corresponding to a size of the printing substrate in accordance with a change in size of the printing substrate.

Abstract: An object of the invention to provide a screen printing machine allows, during maintenance work for one printing device, the other printing device to continue its screen printing work, and a method for controlling an inside temperature of a screen printing machine. A space surrounded by a base (12) and a cover member (11) is divided into two portions by a partition member (14), and two printing devices (13) are accommodated in two working compartments (15), respectively, which are defined by the base (12), the cover member (11) and the partition member (14), whereby temperature-controlled air is blown into each of the working compartments (15) via an air pipe (71) which branches into two air vents (72) opened to the respective working compartments (15).

Abstract: The printing machine comprises at least one transfer system (5) for conveying a substrate (1) onto an impression cylinder (6) and at least one screen (7, 8) of cylindrical or flat shape, with a doctor blade, said screen collaborating with the impression cylinder (6) and intended to print the substrate with an ink containing pigments that can be orientated by a magnetic field and an unloading system (9) for carrying the substrate (1) away. The impression cylinder comprises at least one magnetic element on its impression surface, said magnetic element being positioned at a point corresponding to said impression performed by said screen (7, 8) on said substrate.

Abstract: Label (1) intended to be placed around a container (13) for a product, and this label (1) is strip-shaped and provided with a weakening that forms the dividing line (9) between two parts (2, 3), i.e. a first (2) part and a second part (3) that are in line with one another, whereby the second part (3) is provided with at least one window (10), characterised in that the second part (3) is narrower than the first part (2) and the first part (2) is provided with a thickening (6) that is outside the geometric extension (8) of the second part (3) in the direction of the first part (2).