• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Device (1) for stretching animal skin (2), with a supporting surface (3) for supporting the animal skin (2), a first pair (4), and a second pair (5) on essentially opposite edge regions of the animal skin (2 ) attachable traction means (6), the traction means (6) being connected to a tensioning device (8) for applying a tensile stress to the traction means (6), and each pair (4, 5) of traction means (6) when applied with the Tensile stress forms a tensile stress line (9) in the animal skin (2), the tensile stress line (9) of the first pair (4) enclosing an obtuse and / or acute angle with the tensile stress line (9) of the second pair (5).
    公开号:AT522705A1
    申请号:T50557/2019
    申请日:2019-06-24
    公开日:2021-01-15
    发明作者:
    申请人:Wollsdorf Int Gmbh；
    IPC主号:
    专利说明:

    Device for stretching animal skin
    The invention relates to a device for stretching animal skin according to the preamble of claim 1.
    In leather production, a finished leather hide is created from an animal hide in a sequence of mechanical and chemical processes. Since leather is used in a large number of different applications, the quality of the animal hide must be determined before or after various process steps during leather production in order to determine which application the finished leather hide or parts of the leather hide are suitable for. The value of a dermis is also largely determined by the quality of the finished dermis.
    The inspection of the leather hides is carried out according to the state of the art using visual inspection methods, the inspection being carried out either manually by a person or in an automated manner using a camera system. In the quality control of animal skin, several different testing devices are used to test different quality criteria. The abrasion resistance is tested with a so-called Taber, Veslic or Martindale tester. The kink resistance is tested with a so-called flexometer. The flammability is checked in a flame test. Animal skin refined into leather is exposed to light and UV radiation to test its lightfastness. Another device is used to measure the color of the surface of the animal skin. In addition, the animal skin that has been processed into leather is tested for strength (e.g. tensile strength, tear strength, elasticity). Finally, there is a manual and visual final inspection, which essentially determines the quality in terms of skin damage
    of the leather is assessed as a quality criterion.
    In the case of cowhide, for example, a large number of different types of skin damage are known which can be traced back to injuries, lichen, mites, cracks, fork knocks and other causes. Each type of this skin damage has a typical training, with fork joints, for example, having a small round circumference and
    Skin damage from fattening folds have elongated and parallel outlines.
    Devices for stretching animal skin are used in leather production as part of quality control in order to more easily identify damage to animal hides. Here, the animal skin is stretched, so that the above-mentioned damage or quality features can be determined more easily with test devices known in the prior art. This increases the accuracy of quality control in the
    Leather manufacturing.
    So-called clamping tables with manual operation are known from the prior art. In these, the skin is attached to a tensioning frame that clamps an area of the skin, and then by a movable lifting core which, through its movement, stretches the fixed area from the back of the animal skin. Depending on the lifting height, a percentage rate of a desired elongation can be displayed. The
    Inspection and marking of the leather features with a colored pencil is purely manual.
    From AT 509 382 A1 a device for stretching animal skin is known which, by means of traction means to which a linear tensile stress is applied, stretches the animal skin for a subsequent quality control. In this device, known from the prior art, the most homogeneous stretching of the animal skin is achieved by the traction means stretching the animal skin along two normal tension lines, with the aim of detecting the greatest possible number of quality defects in the animal skin. Due to the varied nature of the damage occurring in animal skins, however, some damage is still not detected in the course of the subsequent quality control. Furthermore, with the device disclosed in AT 509 382 A1, the animal skin cannot be stretched in all directions in many edge areas, which makes it impossible to examine the entire animal skin in one work step. In addition, this previously known tensioning system does not allow any assessment of the elongation values to be expected that this skin will later process
    will have in individual cuts
    It is the object of the present invention to provide a device for stretching animal skin
    to form, which avoids the disadvantages of the prior art.
    According to the invention, the present object is achieved with a device for stretching
    Animal skin with the features of claim 1 solved.
    The device according to the invention for stretching animal skin comprises a supporting surface for supporting the animal skin, as well as a first pair and a second pair of traction means that can be attached essentially to opposite edge regions of the animal skin. The traction means are connected to a tensioning device for applying tensile stress to the traction means, each pair of traction means forming a tensile stress line in the animal skin when the tensile stress is applied. According to the invention, the tension line of the first pair forms an obtuse and / or acute angle with the tension line of the second pair. The formation of an obtuse and / or acute angle between the tension lines results in an inhomogeneous stretching of the animal skin. Surprisingly, the inhomogeneous stretching of the animal skin results in the
    technical effect that depends on the stretching directions or the geometry
    the tension lines a greater number of quality defects and damage in the animal skin can be recognized in the course of quality control than with a homogeneous stretching known in the prior art, or stretching along only a single tension line. This improves the visibility of damage
    in the animal hide, which increases the quality of leather production overall.
    According to the preferred embodiment of the device according to the invention, the device comprises at least one further pair of traction means that can be attached essentially to opposite edge regions of the animal skin, the tensile stress line of each pair of traction means enclosing an obtuse and / or acute angle with the tensile stress line of an adjacent pair of traction means. This has the advantage that further possibilities for varying the stretching of the animal skin are provided, whereby the number of defects in the animal skin which can be made visible with the device according to the invention is increased. Even with a subsequent, purely visual inspection of the animal skin, this results in a significantly higher degree of recognition
    than with inspection tables customary in the state of the art.
    The tension lines of the pairs of tension means preferably intersect essentially in a central region of the animal skin. This has the advantage that the largest possible area of the animal skin can be stretched with the device according to the invention. The entire animal skin can thus be inspected for leather features in one overall setting without further repositioning of sub-areas. In combination with a visual control carried out by a person or through the use of a suitable camera system, there is the clear advantage over systems available on the market that the entire animal skin is in a stretched position without further material transport
    becomes processable.
    According to the preferred embodiment, the device according to the invention comprises a first stop and a second stop. The tensioning device is movably mounted between the first stop and the second stop, the tension means being applied essentially free of tension when the tensioning device rests against the first stop, and the tension when the tensioning device rests against the second stop. The stops define an area within which the animal skin can be stretched. This prevents the animal skin from being overstretched or even mechanically damaged in its structure. The distance between the first stop and the second stop is preferably variable. Since the skins of different animal species have different elasticity limits, this offers the possibility of the size of the stretch that is applied to the animal skin with the device according to the invention,
    adapt to the type of skin. In addition, this also reduces the elasticity of the
    Animal skin can be classified as a value, what with other methods of the prior art
    is impossible.
    According to the invention, the tensioning device is connected to a cable, the cable being designed to move the tensioning device between the first stop and the second stop. This has the advantage that a means that is easily available on the market and for different load ranges can be used for the device according to the invention. The device according to the invention preferably includes two
    cables connected to the tensioning device.
    According to the preferred embodiment of the device according to the invention, the tensioning device comprises at least one receiving means for receiving tension weights. This has the advantage that the device according to the invention can also be operated without the use of an external energy source or voltage supply. The receiving means is preferably an essentially circular plate
    educated. This is preferably arranged parallel to the support surface.
    According to an advantageous embodiment variant, the traction means comprise self-locking tension clamps for fastening the traction means to the animal skin. This has the advantage that a simple and quick fastening method is provided which provides a clamping force proportional to the tensile stress and thus enables the animal hide to be securely fastened to the tensile means. The tension clamps are designed so that
    that they exclude damage to the skin to be stretched
    In an advantageous embodiment variant, the device according to the invention comprises deflection means for deflecting the traction means. These are preferably arranged in an edge region of the support surface. This results in a compact design of the
    Achieved device according to the invention.
    The support surface is preferably designed essentially circular or as a polygon. In addition, the device according to the invention in the preferred embodiment comprises a support bracket, with the support surface, the traction means and the clamping device
    are connected to the support bracket.
    Advantageous embodiments of the device according to the invention as well as alternative ones
    Design variants are explained in more detail below with reference to the figures.
    Figure 1 shows the inventive device for stretching animal skin with a
    Animal skin attached to a support surface of the device in an oblique view from above.
    Figure la shows a self-locking tension clamp of the device according to the invention. Figure 2 shows the device according to the invention in an oblique view from below.
    Figure 3 shows a first stop and a second stop of the device according to the invention.
    FIG. 4 shows a section of a clamping device of the device according to the invention. Figure 5 shows the tensioning device according to the invention with tension weights. Figure 6 shows a course of traction means of the device according to the invention.
    Figure 7 shows a support bracket of the device according to the invention.
    FIG. 8 shows the device according to the invention according to an alternative embodiment variant with hydraulic cylinders.
    FIG. 9 shows the device according to the invention with a support surface with depressions.
    FIG. 1 shows a device 1 according to the invention for stretching animal skin 2. The device 1 comprises a support surface 3, which serves to support the animal skin 2. The device 1 comprises a first pair 4 and a second pair 5 of traction means 6 that can be attached essentially to opposite edge regions of the animal skin 2. The device 1 shown in FIG. 1 in a preferred embodiment comprises eight pairs of traction means 6, the traction means 6 being attached to the animal skin 2 are shown. According to an alternative embodiment of the device 1 according to the invention, ten to thirty pairs of traction means 6 can also be used on the device 1 according to the invention, for example. The pairs of traction means 6 are preferably arranged around the contour and essentially put the entire animal skin 2 in a star shape on tensile stress. The traction means 6 preferably comprise self-locking tension clamps 7 for fastening the traction means 6 to the animal skin 2. A self-locking tension clamp 7 is shown in detail in FIG. 1a. The traction means 6 are connected to a tensioning device 8, which is shown in FIG. 2, FIG. 4 and FIG. The tensioning device 8 provides tension and applies the tension to the tension means 6. Each pair 4 and 5 of tension means 6 to which the tensile stress is applied forms a tensile stress line 9 in the animal skin 2, which are shown in FIG. 1 as dashed lines. According to the invention, the tension line 9 of the first pair 4 of tension means 6 forms an obtuse and / or acute angle α with the tension line 9 of the second pair 5 of tension means 6. Due to the obtuse and / or acute angle α which the tensile stress lines 9 of the first pair 4 and the second pair 5 enclose, an inhomogeneous stretching is achieved in a part or essentially the entire area of the animal skin 2. This has the advantage that the stretching of the animal hide 2 can be selectively adapted to the type of quality defects of interest in the animal hide 2. This facilitates the detection of certain quality defects, and the
    Quality control in leather production improved.
    According to the preferred embodiment of the device 1 according to the invention shown in FIG. 1, the device 1 comprises at least one further pair of pulling means 6 that can be fastened essentially to opposite edge regions of the animal skin 2. In FIG. 1, the device is shown with eight pairs of pulling means 6. The tension line 9 of each pair of traction means 6 forms an obtuse and / or acute angle α with the tension line 9 of an adjacent pair of traction means 6. The obtuse and / or acute angle α can vary between the tension lines 9 of successive pairs of tension means 6. This has the advantage that essentially the entire surface of the animal skin 2 can be stretched with the device 1 according to the invention. Furthermore, the tensile stress lines 9, as shown in FIG. 1, preferably essentially intersect in a central region 10 of the animal skin 2. This has the advantage that the animal skin 2 does not form any folds or tears during stretching and is thus damaged. According to a preferred embodiment of the device 1 according to the invention, the device 1 comprises sixteen pairs of traction means 6. As a result, the tensile stress on the animal hide 2 is evenly distributed and the force per traction means 6 is reduced. This has the advantage that the risk of individual tearing off
    Pulling means 6 is reduced, and the safety for the operating personnel is increased.
    FIG. 2 shows the device 1 according to the invention in a view from below, the clamping device 8 being visible. The device 1 comprises a first stop 11, which is visible in FIG. 3, and a second stop 12, between which the clamping device 8 is movably mounted. The first stop 11 and the second stop 12 are shown in detail in FIG. As can be seen from FIG. 3, in the preferred embodiment of the device 1 according to the invention, a distance A between the first stop 11 and the second stop 12 is variable. When the tensioning device 1 is in contact with the first stop 11, the traction means 6 are essentially tension-free, and when the tensioning device 8 is in contact with the second stop 12, the tensile stress is applied. The variability of the distance A has the advantage that the tensile stress can be adapted to animal skins 2 of different animal species. In FIG. 4, the tensioning device 8 is shown in sections, the tensioning device 8 in FIG. 4 resting against the second stop 12, and the tension means 6 being subjected to the tensile stress. The maximum tensile stress that is applied to the animal skin 2 with the device 1 according to the invention is limited by the first stop 11 and the second stop 12
    becomes.
    FIG. 5 shows the tensioning device 8 of the device 1 according to the invention, which is connected to a cable pull 13. According to the preferred embodiment of the device 1 according to the invention, the device 1 comprises two, as shown in FIG
    cables 13 connected to the tensioning device 8. The cable or cables 13
    shift the tensioning device 8 between the first stop 11 and the second stop 12. The tensioning device 8 preferably comprises a receiving means for receiving tensioning weights 14. This has the advantage that the tensile stress is provided by the weight of the tensioning weights 14, the cables 13 raise the tension weights 14 in the direction of the first stop 11 or the tensioning device 8 is lowered by the tension weights 14 in the direction of the second stop 12. According to an alternative embodiment variant, the cable or cables 13 can also be used instead of the tensioning weights 14 in order to provide a force for moving the tensioning device 8 between the first stop 11 and the second stop 12. By converting the forces applied, a clear prediction of the expected elongation properties of the animal skin 2 can also be made. This facilitates the selection of animal skins 2 for the later cutting, if cut parts have to be created from different animal skins 2, which as a commissioned set consisting of several individual parts must have the same elongation values. Furthermore, as shown in FIG. 8, instead of or in addition to the tension weights 14, hydraulic cylinders 18 connected to the traction means 6 can also be used, which enable both the force applied and the distance to be determined, and thus a calculation of the Allow animal skin 2 applied tensile stress. The use of hydraulic cylinders 18 instead of or in addition to the tension weights 2 also makes it possible to dispense with the first stop 11 and the second stop 12, and the longitudinal expansion or contraction of the hydraulic cylinders 18 directly on the respective hydraulic cylinder 18 or by means of a separate control or measuring device determine. Alternatively, the first stop 11 and the second stop 12 can also be provided on the device 1 with hydraulic cylinders 18. The pressure within the hydraulic cylinder 18 can also be used as an indicator of the elasticity of the animal skin 2. In addition, the hydraulic cylinders 18 can include blocking valves which fix a length of the hydraulic cylinders. Alternatively, all traction means 6 can also be connected to at least one hydraulic cylinder 18. Furthermore, as shown in FIG. 8, each traction means 6 can be connected to its own hydraulic cylinder 18 for applying tensile stress to the traction means 6. In addition to these, a central, additional main hydraulic cylinder (not shown in FIG. 8) can be provided, which is connected to the hydraulic cylinders 18, and after a preferably even tensioning of the traction means 6 by means of the hydraulic cylinders 18 assigned to the individual traction means 6, a central force on
    all traction means 6 applies simultaneously. The receiving means is preferably, as shown in Figure 5, as substantial
    executed circular plate. The circular plate is a preferred one
    Design variant arranged essentially parallel to the support surface 3. In addition, the
    Support surface 3 is preferably essentially circular. This ensures that the tension means 6 are tensioned evenly. According to alternative design variants, the support surface 3, as shown in FIG. 9, can also be square
    or essentially square with round or chamfered corners.
    As shown in Figure 1 and Figure 2, the device 1 comprises deflection means 15 for deflecting the traction means 6. Figure 6 shows the course of the traction means 6 and the clamping device 8 of the device according to the invention in the preferred embodiment. The deflection means 15 guide the traction means 6 along the course shown in FIG. 6 from the support surface 3 to the tensioning device 8. The deflection means 15 are preferably arranged on an edge region of the support surface 3. The traction means 6 are deflected several times by means of the deflection means 15 in order to reduce the tension from the
    Transfer the tensioning device 8 to the animal skin 2.
    The device 1 preferably comprises a support bracket 16 shown in detail in FIG. 2 and in FIG. 7. According to the preferred embodiment of the device 1 according to the invention, the support surface 2, the traction means 6 and the tensioning device 8 are connected to the support bracket 16. Furthermore, the first stop 11, the second stop 12, the deflection means 15 and the cables 13 with the
    Support block 16 be connected.
    According to an alternative embodiment variant of the device 1 according to the invention shown in FIG. 9, the support surface 3 comprises recesses 17, the traction means 6 being at least partially received in the recesses 17. As a result, the traction means 6 essentially form a plane with the support surface 3, which has the advantage that the animal skin 2 is not lifted off the support surface 3 when a tensile stress is applied. As a result, an improved detection of areas with inhomogeneous tension or tensile strength in the animal skin 2 is achieved. In addition, the deflection means 15 and / or the tension clamps 7 are preferably at least partially received in the recesses. The depressions 17 are advantageously designed as guide grooves, as a result of which a reproducible and essentially the same clamping or an essentially the same clamping angle and an essentially identical configuration of the tensile stress lines 9 for each animal skin 2
    is achieved to each other.
    权利要求:
    Claims (17)
    [1]
    1. Device (1) for stretching animal skin (2), with a support surface (3) for supporting the animal skin (2), a first pair (4), and a second pair (5) at substantially opposite edge regions of the animal skin (2) attachable traction means (6), the traction means (6) being connected to a tensioning device (8) for applying tensile stress to the traction means (6), and each pair (4, 5) of traction means (6) when applied with the tensile stress forms a tensile stress line (9) in the animal skin (2),
    characterized in that
    the tension line (9) of the first pair (4) with the tension line (9) of the second
    Pair (5) includes an obtuse and / or acute angle.
    [2]
    2. Device (1) according to claim 1, characterized in that the device (1) comprises at least one further pair of tension means (6) which can be fastened essentially to opposite edge regions of the animal skin (2), the tension line (9) of each pair at Traction means (6) with the tension line (9) of an adjacent pair
    Traction means (6) includes an obtuse and / or acute angle.
    [3]
    3. Device (1) according to one of claims 1 or 2, characterized in that the tensile stress lines (9) of the pairs (4, 5) intersect at the traction means (6) essentially in a central region (10) of the animal skin (2) .
    [4]
    4. Device (1) according to one of claims 1 to 3, characterized in that the device (1) comprises a first stop (11) and a second stop (12), and the clamping device (8) between the first stop (11) ) and the second stop (12) is movably mounted, the traction means (6), when the clamping device (8) rests against the first stop (11), essentially free of tension, and when the clamping device
    (8) rests against the second stop (12), with which tensile stress is applied.
    [5]
    5. Device (1) according to claim 4, characterized in that a distance
    between the first stop (11) and the second stop (12) is variable.
    [6]
    6. Device (1) according to one of claims 4 or 5, characterized in that the clamping device (8) is connected to a cable (13), the cable (13) being designed for the clamping device (8) between the first stop (11) and the second
    Relocate stop (12).
    [7]
    7. Device (1) according to one of claims 1 to 6, characterized in that the clamping device (8) has at least one receiving means for receiving tension weights (14)
    includes.
    [8]
    8. Device (1) according to claim 7, characterized in that the
    Receiving means is designed as a substantially circular plate.
    [9]
    9. Device (1) according to claim 8, characterized in that the plate is arranged essentially parallel to the support surface (3).
    [10]
    10. Device (1) according to one of claims 1 to 9, characterized in that the traction means (6) self-locking tension clamps (7) for fastening the traction means (6) to the
    Include animal skin (2).
    [11]
    11. Device (1) according to one of claims 1 to 10, characterized in that the device (1) comprises deflection means (15) for deflecting the traction means (6).
    [12]
    12. The device (1) according to claim 11, characterized in that the deflection means (15) are arranged on an edge region of the support surface (3).
    [13]
    13. The device (1) according to claim 6, characterized in that the
    Clamping device (8) is connected to two cables (13).
    [14]
    14. Device (1) according to one of claims 1 to 13, characterized in that the device (1) comprises a support block (16), wherein the support surface (3), the traction means (6) and the clamping device (8) with the Support block (16) are connected.
    [15]
    15. Device (1) according to one of claims 1 to 14, characterized in that the bearing surface (3) is substantially circular.
    [16]
    16. Device (1) according to one of claims 1 to 15, characterized in that the bearing surface (3) comprises depressions (17), the tension means (6), the tension clamps (7) and / or the deflection means (15) at least partially in the depressions (17)
    are included.
    [17]
    17. Device (1) according to one of claims 1 to 16, characterized in that
    the traction means (6) are connected to at least one hydraulic cylinder (18).
    11718
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    同族专利:
    公开号 | 公开日
    AT522705B1|2021-06-15|
    EP3757232A1|2020-12-30|
    MA51480A|2021-04-28|
    CN112126721A|2020-12-25|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    NL8005043A|1980-09-05|1982-04-01|Rueti Te Strake Bv|Hide stretching unit has radially movable clamp heads - and driven discs gripping hide edge to guide it between clamp jaws before closing|
    EP0119944A1|1983-03-18|1984-09-26|ETABLISSEMENTS Joseph SOUSSAN S.A.|Automatic tensioning frame for stretching and keeping under tension hides one by one during the drying operation|
    RU2003692C1|1990-09-21|1993-11-30|Евгений Александрович Колкунов|Device for clamping semifinished product on stretching machines|
    FI57617C|1979-01-18|1980-09-10|Viljanmaa Antti|SPRING SPEAKING|
    AUPM761094A0|1994-08-23|1994-09-15|Tanning Technologies Pty Ltd|Treatment of hides|
    AT509382B1|2010-01-18|2011-12-15|Wollsdorf Leder Schmidt & Co Gmbh|TEST EQUIPMENT FOR DETERMINING THE QUALITY OF LEATHER|
    EP3171903A2|2014-07-23|2017-05-31|Boston Scientific Scimed, Inc.|Devices and methods for fixation of animal tissue|CN113005237A|2021-02-24|2021-06-22|张晓莲|Clausena lansium stretching device for bass drum production|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    ATA50557/2019A|AT522705B1|2019-06-24|2019-06-24|DEVICE FOR STRETCHING ANIMAL SKIN|ATA50557/2019A| AT522705B1|2019-06-24|2019-06-24|DEVICE FOR STRETCHING ANIMAL SKIN|
    MA051480A| MA51480A|2019-06-24|2020-05-25|ANIMAL SKIN STRETCHING DEVICE|
    EP20176259.8A| EP3757232A1|2019-06-24|2020-05-25|Device for stretching animal skin|
    CN202010581697.1A| CN112126721A|2019-06-24|2020-06-23|Equipment for tensioning animal skin|
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