EP1607218B1 - Protective device for holding a stencil printing master and frame for stretching a stencil - Google Patents

Abstract

The protective device is designed with each adjoining protective strip (3) forming the frame (1) supported against one another by their end regions (4,5) to allow relative movement between them. A guide element can be mounted between adjoining protective strips. The guide element is disc shaped and engages in a corresponding groove in the adjoining end regions of the adjacent protective strips.

Description

The invention relates to a protective device with a protective strips having frame for holding a printing template in a plane and with connecting means for attachment to a stencil clamping frame, the protective strips the printing template over the circumference, the edge of the stencil printing record, each adjacent protective strips forming the frame each supported a relative movement against each other. Moreover, the invention relates to a stencil clamping frame for mounting a printing template held in an aforementioned protective device.

Such a protective device is already by the GB 2 388 073 known, in which the adjacent protective strips are arranged relative to each other allowing a relative movement. These are connected to each other via a connecting element, wherein the relative movement takes place in weighting the longitudinal extent of the protective strips.

Also at the US 3,482,343 a relative movement of the protective strips of a clamping frame via a corner element is made possible, which is supported by means of a screw connection to the protective strips. The protective strips have for this purpose a sufficient distance from each other.

Furthermore, already discloses the US 5,271,171 a clamping frame with protective strips, which are supported by means of a compression spring under bias in a connecting the protective strips corner element, wherein the protective strips are spaced corresponding to each other. However, the tenter relates to another technical field, namely a tenter for a fabric.

A protective device is as part of a film template assembly of the US 64 94 134 B2 known. The film template assembly comprises a film template attached to a rigid frame in a planar arrangement. The rigid frame has an upright side wall and a support edge extending inwardly from the upright side wall. The foil template rests on the support edge, and the outer edge of the foil template is disposed adjacent to the inner surface of the side wall. The periphery of the foil template is attached to the rigid frame. Due to the rigid frame distortions in the foil stencil are difficult to avoid. The known foil template arrangement Can be mounted on a tenter to perform a printing operation.

Furthermore, it is off DE 197 49 449 C1 a template clamping frame for mounting stencils of metal or plastic films for stencil printing is known, which stencil clamping frame has an actuatable by means of a pressure medium clamping device for adjustable clamping strips. The clamping bars have gripping pins engaging in perforations of a template. The clamping device is arranged by arranged in a frame profile, can be acted upon evenly with a pressure medium, elastically deformable clamping tubes, against which the clamping bars on the front. Furthermore, the clamping bars are provided on the back with pivot cams, which are supported on a final profile of the frame profile, in such a way that the clamping bars are pivotable by means of the clamping hoses for clamping the template on the pivoting cam. With this template clamping frame a clamping force is evenly applied to the entire working surface of the template. Distortions of the template are thus avoided. In the known template clamping frame, the template formed by a metal or plastic film is to be inserted loosely by hand.

The invention has for its object to provide a protective device of the type mentioned above, on the one hand protects a printing template from damage and on the other hand allows error-free clamping of the printing stencil in a stencil clamping frame. In addition, the invention has for its object to provide a stencil clamping frame of the type mentioned above, which allows precise printing with the printing template held in the protective device.

The first object is achieved with a protective device of the type described above, in each adjacent protective strips forming the frame with one of their end portions relative to each other allowing each other are supported by a respective guide element is disposed between adjacent protective strips and the frame four a rectangle having protective strips.

The protective device according to the invention thus has a number of independent protection strips, which are arranged flexibly to each other. In this way, can be reliably avoided by holding the stencil sheet in the protection tension in the stencil. The printing stencil is in particular a metal or a plastic film or a thin, mechanically unstable sheet. Such printing stencils are preferably used in so-called SMD printing machines, with SMD surfacemounted device or surface mounted device means. Especially for such an application, it is of great advantage that the protective device according to the invention enables printing with high precision and very low tolerances. Compared to the known from the prior art rigid frame distortions of the stencil, which would lead to an insufficient printing result, can be safely avoided in the protective device according to the invention. In addition, the mechanical load of the printing stencil with the invention is significantly reduced, so that the life of the template is not significantly increased. For example, tears in the printing stencil can be virtually ruled out without external force, since the stencil is held in the protective device almost without tension. A cohesion of the frame of the protective device according to the invention is not due to an example, rigid structure of the frame, but due to the pressure exerted by the held in the frame stencil on the guard rails train. In principle, potential distortions in the printing stencil are automatically compensated for by the relative mobility of the protective strips. Decisive here is a relative mobility of the protective strips in the frame plane and thus parallel to a plane of the printing stencil; that is, the frame plane and the plane of the stencil collapse or do not intersect in space. With the invention, the printing stencil can also advantageously remain in the protection device over its entire service life; a re-tensioning and / or smoothing of the template, as required in the known rigid frame, can be advantageously eliminated. In particular, due to the covering of the edge of the printing template by the protective strips is an operator who the printing stencil example, in a printing system or expands reliably from injury, especially against cuts by a sharp edge of the stencil protected. As a result, the operator is also reduced the risk of inflammation, which can be caused by wound contamination with toxic, possibly the printing stencil adhering materials. The risk of injury to the operator by the printing template is eliminated with the invention. Covering the edge of the stencil generally means that this edge is not completely exposed; For example, the protective strips may have an edge projecting into the plane of the printing stencil or beyond. The edge of the printing stencil may be spaced from such an edge of the protective strips in a plane direction of the printing stencil. In principle, it is also conceivable, for example, that the edge of the protective strips surrounds the edge of the printing template in a U-shape. By means of the connecting means, the protective device can be connected to the printing template in a simple manner for prepressing the printing stencil with a stencil clamping frame. Preferably, the four protective strips can form a square frame.

The protective device is particularly simple in construction and easy to manufacture, if, according to an advantageous embodiment of the invention, the guide element is disc-shaped and engages in a corresponding groove in the adjacent end regions of the adjacent protective strips. The guide element may be, for example, an inserted into the grooves sheet metal plate.

With a simple construction, the guide element can enable the protective strips, in particular a linear relative movement, preferably in a plane parallel to the frame plane, if, according to an advantageous development of the invention, the guide element has a biconvex shape and if the corresponding grooves have a concave groove base.

A particularly simple and cost-effective guide element can be used for the protection device, according to another advantageous embodiment of the invention, the guide element is designed as a bolt and each engages in a corresponding recess in the adjacent end portions of the adjacent protection strips and that the bolt in at least one of the recesses is arranged with respect to the pin axis axial play and radial play. The axial and radial play ensures the relative mobility of the protective strips against each other, due to which relative to the invention, the pressure stencil is almost force-free in the protective device can be arranged; The protective device is held together not by the guide elements, but by the printing template. The recess is preferably aligned in a first of the adjacent protective strips in the axial direction of the protective strip and in the second of the adjacent protective strips in a direction perpendicular to the axial direction of the protective strip. The recesses are preferably blind holes.

In particular, the handling of the guide element during assembly of the protective device can be simplified if, according to another advantageous embodiment of the invention, the guide element is formed as an angle and engages in a corresponding recess in the adjacent end regions of the adjacent protective strips and that at least one angle leg of the angle in the corresponding recess with respect to the axis of the angle leg axial play and radial play is arranged. The axial and radial play ensures the relative mobility of the protective strips against each other, due to which relative to the invention, the pressure stencil is almost force-free in the protective device can be arranged; the guard is held together not by the guide elements, but by the Stencil. Preferably, the recess in both of the adjacent protective strips is aligned in each case in the axial direction of the protective strip. The recesses are preferably blind holes.

According to another advantageous embodiment of the invention, the protective strips each have at least one holding bolt extending perpendicular to the frame plane for engaging in each case a corresponding recess in the printing template. As a result, a targeted and particularly simple arrangement of the printing template is ensured on the protective strips.

A fixation of the printing stencil can be easily achieved in that, according to an advantageous embodiment of the invention, the retaining bolts have a plastically deformable material, for example plastic or aluminum. For example, the material can be deformed after passing through a recess of the printing template by a retaining bolt such that a damage-free removal of the printing template of the protective strips no longer possible and the stencil is permanently held securely in the frame. Since the invention allows the printing stencil to remain in the protective device over its entire service life, which depends on the printing results to be achieved with it, an intermediate separation of printing stencil and protective strips is generally not necessary.

According to another advantageous development of the invention, the retaining bolts have a radial groove structure at their end which can be passed through the pressure stencil. Such a groove structure, which may also be formed thread-shaped, for example, allows a screwing or latching attaching the pressure stencil against the protective strips holding down spring washers on the retaining bolts.

Assign according to another advantageous embodiment of the invention, the retaining bolts on their the stencil passable through an axial recess, it can in a simple manner, for example, for screwing a hold-down for the printing template in the retaining bolts or for applying a tool for targeted plastic deformation of the retaining bolts be used.

A particularly precise arrangement of the printing stencil in the protective device can be achieved if, according to another advantageous development of the invention, the protective strips each extend at least one perpendicular to the frame plane Positioning pin for engaging each have a corresponding positioning recess in the printing template. The required for manufacturing and assembly reasons - low - game of positioning in the Positionierausnehmung is preferably less than the game, which allow guide elements between adjacent protective strips of the protective device. In addition to an exact positioning of the printing stencil the positioning pin can advantageously also serve a coding, so that with his help, the printing template, for example, only in a correct page assignment in the protective device can be arranged and / or that with his help, for example, only printing stencils of a designated type in the protection device can be arranged.

According to another advantageous embodiment of the invention, at least one of the protective strips in cross-section U-shaped, and the edge of the printing template is receivable between the legs of the U; Preferably, all protective strips are U-shaped, so that in particular particularly thinner printing stencils, for example, with a thickness of less than 0.1 mm, can be safely absorbed. In this way, the printing stencil can be kept very safe and particularly well protected from damage in the protection device. The U-shaped configuration in the protective strip can preferably be formed by a groove in the protective strip or by an attachment wall on the protective strip, which neck wall corresponds to a wall of the protective strip opposite the attachment wall.

The above second object is achieved with a template clamping frame of the type described above, in which a seat for receiving the protective device and a connecting device for fixing the protective device is provided.

With the inventive, the protective device receiving seat is advantageously ensured that an unambiguous, accurate fit of the printing template holding protective device and stencil clamping frame is done. This ensures high printing precision. Furthermore, the connecting device ensures that the protective device can remain securely and permanently assigned to the template clamping frame while maintaining exact geometries in a predetermined position, without a deterioration of the printing result occurring. In order to be able to ensure with the template clamping frame an absolutely exact, distortion-free and error-free clamping of the printing template required for high printing precision, it is important that the protective device with the printing template is arranged completely in the seat before being clamped with the aid of the template clamping frame. The clamping of the printing stencil itself For example, it can advantageously be done in the same way as in the case of the template clamping frame known from the prior art described at the outset.

According to an advantageous embodiment of the invention can be achieved in a particularly simple manner a very precise and accurate allocation of stencil clamping frame and protective device in that the seat has a stop perpendicular to the frame plane of the protective device and a stop parallel to the frame plane of the protective device.

Due to the high importance of the positioning of the protective device on the template clamping frame for a clean, accurate printing result, another embodiment of the invention is particularly advantageous, according to which the seat has an optical marking for displaying a complete recording of the protective device. This allows an operator to check immediately and without doubt the arrangement of the protective device for correctness.

According to another advantageous development of the invention, the connecting device has a recess for the latching engagement of a connecting pin of the protective device. With the latching realized by means of the connecting pin and the recess, a cost-effective, easy-to-disconnect connection of the protective device and the template clamping frame is made possible.

A low production cost with low material costs and high durability has the latching, according to an embodiment of the invention, the recess has an engageable in a circumferential groove of the connecting pin O-ring.

According to another advantageous embodiment of the invention, a particularly easy-to-use connecting device can be achieved in that the connecting device has a sliding element releasing the protective device in a first sliding position and in a second sliding position with the template clamping frame form-fitting connecting sliding element.

Figur 1

eine als Rahmen ausgebildete Schutzvorrichtung für eine Druckschablone in einer Draufsicht.

Figur 2

ein vergrößertes Detail der Schutzvorrichtung nach Figur 1,

Figur 3

einen Schnitt des Details nach Figur 2 entlang Linie III - III in Figur 1,

Figur 4

einen Teilschnitt des Rahmens nach Figur 1 mit einer von einem ersten Haltebolzen gehaltenen Druckschablone,

Figur 5

einen Teilschnitt des Rahmens nach Figur 1 mit einer von einem zweiten Haltebolzen gehaltenen Druckschablone,

Figur 6

einen Eckbereich einer Druckschablone in einer Draufsicht,

Figur 7

einen Teilschnitt eines Schablonenspannrahmens mit einer Schutzvorrichtung, einer Druckschablone und einer Verbindungseinrichtung,

Figur 8

eine Seitenansicht einer Aufnahmeleiste einer Schnellsperre,

Figur 9

die Aufnahmeleiste nach Figur 8 in einer Draufsicht,

Figur 10

einen Eckbereich einer Schutzvorrichtung mit Haltehaken in einer Draufsicht,

Figur 11

die Schutzvorrichtung nach Figur 10 in einer Seitenansicht,

Figur 12

einen Teilschnitt eines Schablonenspannrahmens mit einer Schutzvorrichtung und einer alternativen Verbindungseinrichtung,

Figur 13

einen Teilschnitt des Rahmens nach Figur 1 mit einer von einem dritten Haltebolzen gehaltenen Druckschablone,

Figur 14

eine Schutzvorrichtung mit einer Vorpositivniereinrichtung für eine Druckschablone in einer Ansicht von unten,

Figur 15

einen Teilschnitt der Schutzvorrichtung nach Figur 14,

Figur 16

einen Eckbereich einer Schutzvorrichtung mit einem bolzenförmigen Führungselement,

Figur 17

einen Eckbereich einer anderen Schutzvorrichtung mit einem winkelförmigen Führungselement.

Figur 18

einen Ausschnitt einer Schutzleiste in einer Draufsicht,

Figur 19

einen Schnitt der Schutzleiste nach Figur 18,

Figur 20

einen Ausschnitt einer weiteren Schutzleiste in einer Draufsicht und

Figur 21

einen Schnitt der Schutzleiste nach Figur 20.

The invention allows numerous embodiments. To further clarify its basic principle, various of them are shown schematically in the drawing and described below. The drawing shows in

FIG. 1

a trained as a frame protection device for a printing stencil in a plan view.

FIG. 2

an enlarged detail of the protective device according to FIG. 1 .

FIG. 3

a cut of the details after FIG. 2 along line III - III in FIG. 1 .

FIG. 4

a partial section of the frame after FIG. 1 with a printing template held by a first retaining bolt,

FIG. 5

a partial section of the frame after FIG. 1 with a printing template held by a second retaining bolt,

FIG. 6

a corner region of a printing stencil in a plan view,

FIG. 7

a partial section of a stencil clamping frame with a protective device, a printing template and a connecting device,

FIG. 8

a side view of a recording bar of a quick lock,

FIG. 9

the receiving strip of Figure 8 in a plan view,

FIG. 10

a corner region of a protective device with holding hook in a plan view,

FIG. 11

the protection device after FIG. 10 in a side view,

FIG. 12

a partial section of a stencil clamping frame with a protective device and an alternative connecting device,

FIG. 13

a partial section of the frame after FIG. 1 with a printing template held by a third retaining bolt,

FIG. 14

a protective device with a Vorpositivniereinrichtung for a stencil in a view from below,

FIG. 15

a partial section of the protective device according to FIG. 14 .

FIG. 16

a corner region of a protective device with a bolt-shaped guide element,

FIG. 17

a corner region of another protective device with an angular guide element.

FIG. 18

a section of a protective strip in a plan view,

FIG. 19

a section of the protective strip after FIG. 18 .

FIG. 20

a section of another protective strip in a plan view and

FIG. 21

a section of the protective strip after FIG. 20 ,

Corresponding elements of the embodiments are provided in all figures with the same reference numerals.

FIG. 1 shows in a plan view formed as a square frame 1 protective device 2 for holding a printing template not shown in a plane. The frame 1 has four protective strips 3, wherein each adjacent protective strips 3 are supported with their respective end portion 4, 5 to each other. In this case, a relative movement between the adjacent protective strips 3 is possible, in this embodiment a relative movement in the frame plane of the frame 1 and along the opposite corners 6, 7 of the frame 1 connecting and a contact area 8 of the protective strips 3 intersecting line 9 is possible. Overall, the frame 1 has four such contact areas 8. The protective strips 3 are preferably formed by aluminum profiles or plastic profiles.

A through a frame A in FIG. 1 characterized, a contact area 8 of the protective strips 3 comprehensive detail is in FIG. 2 shown enlarged. It can be seen that between the adjacent protective strips 3 a - here biconvexes - disc-shaped guide member 10 is arranged. The guide element 10 is a in each case a dashed line groove 11 in the end regions 4, 5 of the adjacent protective strips 3 inserted sheet metal plate. The grooves 11 are arranged in a plane parallel to the frame plane of the frame 1 and have a corresponding with the biconvex shape of the guide member 10 concave groove bottom 12th

A section along line III - III in FIG. 1 of the above details FIG. 3 , It can be seen that the protective strips 3 a projecting edge 13 on its outer side 14th exhibit. Inwardly directed, that is oriented towards the center of the frame, the protective strips 3 are provided with a support surface 15 for the printing stencil. The support surface 15 is continuous on the entire frame 1 ( FIG. 1 ) provided on the inside for supporting the printing stencil. FIG. 3 shows the inserted guide element 10 also in section.

A section along line IV - IV in FIG. 1 but including a stencil 16 shows FIG. 4 , The printing template 16 abuts the inner bearing surface 15 of the protective strip 3 and is supported by this. The edge 13 of the protective strip 3 covers the outer edge 17 of the printing template 16 and thus protects the one hand, the printing template 16 (for example, before tears) and on the other hand, a printing template 16 handling operator (for example, from injuries such as skin incisions, they on a sharp-edged edge 17 of the stencil 16 could pull).

The printing template 16 is held by an inserted into the protective strip 3, perpendicular to the frame plane of the protective strip 3 having frame extending retaining pin 18 which engages through a recess 19 of the printing stencil 16. The retaining pin 18 has at its the printing template 16 by cross-end 20 has a central axial recess 21 which corresponds to a deformation tool 22. The retaining bolt 18 has a plastically deformable material, such as a plastic, or aluminum, so that a blow with the forming tool 22 on the printing stencil 16 by cross-end 20 of the support pin 18 to the permanent compression, which has a widening of its outer periphery result leads. As a result, the printing template 18 is securely held on the bearing surface 15 of the protective strip 3. The situation shown applies to all protective strips 3 of the frame. 1

An alternative solution with another retaining pin 23 shows FIG. 5 in a FIG. 4 corresponding view. The retaining pin 23 extends perpendicular to the frame plane of the protective strip 3 having frame and passes through the printing template 16 in a corresponding recess 19. At its the printing stencil 16 by cross, provided with a chamfer 24 end 25 of the holding rollers 23 has a radial groove structure 26, in particular a External thread, on. On the groove structure 26, a conical spring washer 27 is attached or screwed and holds the stencil 16 reliably on the support surface 15 of the protective strip 3. To protect the printing stencil 16, a washer 28 is disposed between the spring washer 27 and pressure template 16.

In FIG. 6 a corner region of a printing template 16 is shown with recesses 29 which are formed star-shaped. Such recesses 29, attached to retaining bolts 23 after FIG. 5 , spare in the embodiment according to FIG. 5 By contrast, with the star-shaped recesses 29 and corresponding retaining bolts, the pressure stencil is automatically held on the frame of a protective device.

A portion of a stencil clamping frame 30 for mounting a stencil sheet 16 held in a protector 2 is In FIG. 7 shown in a partial section. The template clamping frame 30 has a seat 31 for receiving the protective device 2 and a connecting device 32 for attaching the protective device 2 to the template clamping frame 30. The seat 31 is formed by a step 33 surrounding the template clamping frame 30. The step 33 corresponds to a projecting shoulder 34 of the protective device 2, which is formed by projecting edges 13 of protective strips 3 and provided on the protective strips 3, arranged at an angle of 90 ° relative to the edges 13 bearing surfaces 15 for the printing template 16. The paragraph 34 runs around a the school strips 3 having flat frame 1 of the protective device 2.

The seat 31 has both a first stop 35 perpendicular to the frame plane of the frame 1 of the protective device 2 and a second stop 36 parallel to the frame plane of the frame 1 of the protective device 2, so that the protective device 2 is spatially exactly positioned relative to the template clamping frame 30. For easy control of the positioning of the protective device 2, the seat 31 has an optical marking 37, which is applied to the step 33 in this embodiment as a color layer in a signal color, for example, bright red.

The connecting device 32 has a quick-lock with a on the stencil clamping frame 30 by means of a screw 38, for example, a hexagon socket screw, mounted receiving bar 39 which is provided with a recess 40 in which an O-ring 41 is arranged. In the recess 40 engages a arranged on the protective device 2 connecting pin 42 with a circumferential groove 43 a. The circumferential groove 43 receives the O-ring 41, thus providing attachment of the protector 2 to the template clamping frame 30. The female connector 39 is fixed in a groove 47 of the template clamping frame 30. For manual unlocking of protective device 2 and stencil clamping frame 30 is gripped in the groove 47 and the protective device 2 is raised.

For clarity, in Figures 8, 9 the recording bar 39 of the quick lock after FIG. 7 with the associated connecting pin 42 and cooperating with the connecting pin 42, the latch inducing O-ring 41 shown separately in a side and a top view. A recess 44 serves to receive the screw 38 (FIG. FIG. 7 ) for attachment to the template clamping frame.

In FIG. 10 (Top view) and FIG. 11 (Side view), a corner region of a protective strips 3 having protective device 2 is shown, which has openings 45 in the protective strips. The openings that do not collide with the printing template, are provided for receiving retaining hooks 59, 60, where the protective device 2 can be hung when not in use held in her stencil printing at a storage place. Also for washing and drying of the stencil can advantageously be done by means of the holding hooks 59, 60.

FIG. 12 2 shows a section of a stencil clamping frame 30 with a protective strip 3 of a protective device 2 and a connecting device 32 for connecting stencil clamping frame 30 and protective device 2. The connecting device 32 has a sliding element 46 which is guided in a groove 47 of the template clamping frame 30. The sliding element 46 is fixedly connected to a screw 48 having a radially projecting head 48, the head 48 being guidable on a groove shoulder 50 of a groove 52 in the protective strip 3. At a first end of the groove 52 in the protective strip 3, the groove shoulder 50 has a widening 51 through which the head 48 of the screw 49 can be passed, whereas the groove shoulder 50 engages under the head 48 of the screw 49 at the second end of the groove 52 , In the in FIG. 12 shown position, the sliding element 46 is in a second, the protective device 2 positively connected to the template clamping frame 3D Schlebefellung. In a first sliding position, not shown, the protective device can be removed from the template clamping frame 30 in that the widening 51 of the groove shoulder 50 of the groove 52 in the protective strip 3 releases the head 48 of the screw 49 located on the sliding element 46. The sliding member 46 is further provided with two recesses 53, into which a bolt 54, which is arranged on the template clamping frame 30 spring-loaded slidably engageable. The bolt 54 secures the sliding element 46 in the first and in the second sliding position.

Such, in FIG. 12 Jointing device 32 shown in general may also serve to protect protective strips 3 without a printing template on a stencil clamping frame, as is apparent, for example DE 197 49 449 C1 It is known to apply to edge regions of a printing template arranged on the stencil clamping frame and / or for tensioning the printing stencil Cover provided gripping pins of the template clamping frame. As a result, the protective strips 3 are very versatile.

Another way of holding a printing template 16 on a protective strip 3 shows FIG. 13 in a FIGS. 4, 5 corresponding view. A holding bolt 55 extends perpendicular to the frame plane of the protective strip 3 having frame and passes through the pressure template 16 in a corresponding recess 19. At its the stencil printing plate 16 by cross-end 56, the retaining pin 55 has a circumferential groove 57 which carries an O-ring 58. The O-ring 58 holds the printing template 16 on the protective strip. 3

A protective device 2 with a pre-positioning device 61 for a printing template 16 shows FIG. 14 in a view from below. The protective device 2 is formed as a square frame 1 and has four protective strips 3. The protective strips 3 each have a positioning pin 62 extending perpendicularly to the frame plane for engaging in each case a positioning recess 63 corresponding to the respective positioning pin 62 in the printing template 16. Openings 45 in corner regions of the protective strips 3 and approximately centrally in the longitudinal direction of the protective strips 3 arranged openings 89 serve a suspension of the protective device 2 with pressure template 16th

A partial section along line XV - XV of the protection device in FIG. 14 shows FIG. 15 , It can be seen that the positioning diameter 62, which has a diameter D1, by way of example 3.95 mm, has the positioning diameter 63, which has a diameter D2, by way of example 4.00 mm, in the pressure template 16. The positioning pin is inserted in the protective strip 3.

A corner region with two adjacent protective strips 3, 3 ', which are each supported with one of their end portions 4, 5 a relative movement against each other allowing a protection device FIG. 16 , Between the adjacent protective strips 3, 3 ', a guide element 64 designed as a bolt 65 is arranged, wherein it can be seen that exactly two such guide elements 64 are provided in this embodiment between the adjacent protective strips 3. The bolts 65 engage on the one hand In a trained as a blind hole, in the axial direction of a first protective strip 3 of the adjacent protective strips 3, 3 'aligned recess 66 and on the other hand in a trained as a blind hole, in a direction perpendicular to the axial direction of a second protective strip 3' of the adjacent Protective strips 3, 3 'aligned recess 67. It can be clearly seen in each case based on the pin axis 70 axial play 68, 69 of the bolt 65 in the Recesses 66, 67. In addition, based on the bolt axis 70 radial play 71 of the bolt 65 in the recesses 66, 67, which radial clearance 71 is smaller than the respective axial play 68, 69. Axial play 68, 69 and radial clearance 71 allow a relative mobility of the Protective strips 3, 3 'to.

FIG. 17 shows a similar corner region of a protective device, but with a different guide member 72. This guide member 72 is formed as an angle 73 and engages with an angle leg 74, 75 in corresponding recesses 76, 77 of adjacent, mutually supported protective strips 3, 3 'a. Each of the angle legs 74, 75 is to provide a relative mobility of the protective strips 3, 3 'in the respective corresponding recesses 76, 77 - with respect to the respective axis 82, 83 of the angle legs 74, 75 - with axial play 78, 79 and with radial play 80, 81 arranged.

In FIG. 18 a section of a protective strip 3 is shown in a plan view of which protective strip. 3 FIG. 19 shows an enlarged section along line XIX - XIX. The protective strip 3 is U-shaped in cross-section, wherein the U-shaped configuration is formed by a groove 84 which lies in the plane in which the pressure stencil is to be arranged in the protective strip 3. Between the legs 85, 86 of the U thus formed a printing template is receivable.

A section of a similar protective strip 3 is in FIG. 20 shown in a plan view of which protective strip. 3 FIG. 21 shows an enlarged section along line XXI - XXI. The protective strip 3 is formed according to this embodiment in cross section U-shaped. In this case, the U-shaped configuration is formed by a shoulder wall 87 on the protective strip 3, wherein the neck wall 87 with one of the shoulder wall 87 opposite wall 88 of the protective strip corresponds and thus legs 85, 86 of the U forms, between which a printing template is receivable.

LIST OF REFERENCE NUMBERS

1

- Frame

2

- protection device

3, 3 '

- Protection strip

4

- End area

5

- End area

6

- corner

7

- corner

8th

- Contact area

9

- line

10

- Guide element

11

- groove

12

- groove bottom

13

- Edge

14

- outside

15

- Support surface

16

- Printing template

17

- Edge

18

- retaining bolt

19

- recess

20

- The End

21

- recess

22

- Deformation tool

23

- retaining bolt

24

- bevel

25

- The End

26

- groove structure

27

- Spring washer

28

- Washer

29

- recess

30

- template clamping frame

31

- Seat

32

- Connecting device

33

- Step

34

- Paragraph

35

- Attack

36

- Attack

37

- Marking

38

- screw

39

- Recording bar

40

- recess

41

- O-ring

42

- Connecting pin

43

- circumferential groove

44

- recess

45

- breakthrough

46

- Sliding element

47

- groove

48

- Head

49

- screw

50

- Nutabsatz

51

- widening

52

- groove

53

- recess

54

- Bolt

55

- retaining bolt

56

- The End

57

- circumferential groove

58

- O-ring

59

- Holding hook

60

- Holding hook

61

- Prepositioning device

62

- Positioning pin

63

- Positioning recess

64

- Guide element

65

- Bolt

66

- recess

67

- recess

68

- axial play

69

- axial play

70

- Bolt axis

71

- radial play

72

- Guide element

73

- Angle

74

- angle leg

75

- angle leg

76

- recess

77

- recess

78

- axial play

79

- axial play

80

- radial play

81

- radial play

82

- axis

83

- axis

84

- groove

85

- thighs

86

- thighs

87

- Boundary wall

88

- wall

89

- Breakthroughs

A

- Frame

D1

- diameter

D2

- diameter

Claims (17)

1. Protective device with a frame for holding a printing screen in a plane, which frame has protective strips, and with connecting means for fastening to a screen-clamping frame, wherein the protective strips accommodate the printing screen over its periphery, covering the edge of the printing screen, wherein in each case adjacent protective strips are supported while forming the frame so as to allow a relative movement with respect to each other, characterised in that in each case adjacent protective strips (3) are supported against each other with in each case one of their end regions (4, 5) so as to allow in each case the relative movement with respect to each other, in that a guide element (10, 64, 72) is arranged in each case between adjacent protective strips (3) and the frame (1) has four protective strips (3) which form a rectangle.
2. Protective device according to Claim 1, characterised in that the guide element (10) is disc-shaped and engages in each case in a corresponding groove (11) in the abutting end regions (4, 5) of the adjacent protective strips (3).
3. Protective device according to Claim 2, characterised in that the guide element (10) has a biconvex form and that the corresponding grooves (11) have a concave groove bottom (12).
4. Protective device according to Claim 1, characterised in that the guide element (64) is in the form of a bolt (65) and engages in each case in a corresponding recess (66, 67) in the abutting end regions (4, 5) of the adjacent protective strips (3, 3'), and that the bolt (65) is arranged in at least one of the recesses (66, 67) with (70) axial play (68, 69) and radial play (71) with respect to the bolt axis.
5. Protective device according to Claim 1, characterised in that the guide element (72) is in the form of a bracket (73) and engages in each case in a corresponding recess (76, 77) in the abutting end regions (4, 5) of the adjacent protective strips (3, 3'), and that at least one limb (74, 75) of the bracket (73) is arranged in the corresponding recess (76, 77) with axial play and radial play with respect to the axis (82, 83) of the bracket limb (74, 75).
6. Protective device according to at least one of the preceding claims, characterised in that the protective strips (3) have in each case at least one holding bolt (18, 23, 55) for engaging through in each case one corresponding recess (19) in the printing screen (16), which holding bolt extends perpendicularly to the frame plane.
7. Protective device according to Claim 6, characterised in that the holding bolts (18) have a plastically deformable material.
8. Protective device according to at least one of Claims 6 and 7, characterised in that the holding bolts (23) have a radial score structure (26) at their ends (25) which engage through the printing screen (16).
9. Protective device according to at least one of Claims 6 to 8, characterised in that the holding bolts (18) have an axial recess (21) at their ends (20) which engage through the printing screen (16).
10. Protective device according to at least one of the preceding claims, characterised in that the protective strips (3) have in each case at least one positioning pin (62) for engaging through in each case one corresponding positioning recess (63) in the printing screen (16), which positioning pin extends perpendicularly to the frame plane.
11. Protective device according to at least one of the preceding claims, characterised in that at least one of the protective strips (3) has a U-shaped cross section, and that the edge of the printing screen can be accommodated between the limbs (85, 86) of the U.
12. Screen-clamping frame with a printing screen which is held in a protective device according to at least one of the preceding claims, characterised in that a seat (31) is provided for accommodating the protective device (2) and a connecting arrangement (32) for fastening the protective device (2).
13. Screen-clamping frame according to Claim 12, characterised in that the seat (31) has a stop (35) perpendicular to the frame plane of the protective device (2) and a stop (36) parallel to the frame plane of the protective device (2).
14. Screen-clamping frame according to at least one of Claims 12 and 13, characterised in that the seat (31) has a visible marking (37) to indicate complete accommodation of the protective device (2).
15. Screen-clamping frame according to at least one of Claims 12 to 14, characterised in that the connecting arrangement (32) has a recess (40) for locking engagement of a connecting pin (42) of the protective device (2).
16. Screen-clamping frame according to Claim 15, characterised in that the recess (40) has an O-ring (41) which can engage in a peripheral groove (43) in the connecting pin (42).
17. Screen-clamping frame according to at least one of Claims 12 to 16, characterised in that the connecting arrangement (32) has a sliding element (46), which releases the protective device (2) in a first sliding position and connects the protective device to the screen-clamping frame (30) in a form-fitting manner in a second sliding position.

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