Patent Publication Number: US-2021186230-A1

Title: Fastening device for fastening a mattress

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a National Stage of PCT Application No. PCT/EP2018/065831 filed on Jun. 14, 2018, which claims priority to German Patent Application No. DE 10 2018 109 253.9 filed on Apr. 18, 2018, the contents each of which are incorporated herein by reference thereto. 
    
    
     TECHNICAL FIELD 
     The invention refers to a fastening device for fastening a mattress on a mattress support, particularly a mattress support of a nursery bed. The invention refers also to a nursery bed having a mattress support as well as a mattress that is attached or can be attached on the mattress support by means of the fastening device. 
     BACKGROUND 
     In some beds and particularly nursery beds in therapy units such as hospitals, care centers or rehabilitation clinics, frequently beds are provided in which the mattress support comprises multiple support sections that can be angled relative to each other. In doing so, the upper body of a patient can be raised for example. Also patients can be brought in a sitting position in order to facilitate standing up. Many patients are unable to raise themselves and to stand up without this support. 
     If the mattress support is brought into a seat position, the mattress shall not be distanced from the mattress support, but must further on abut on the mattress support and shall abut on the mattress support as tight as possible. If the mattress is released from the mattress support, the mattress tries to assume its non-elastically deformed stretched position. An unintentional release of the fastening device can be dangerous for the patient. The patient and also the support and caring personnel must be able to rely on the mattress remaining rigidly anchored at the mattress support, if individual support sections of the mattress support are angled for raising the patient. 
     In order to ensure such a rigid connection, mattresses are frequently fastened by means of belts and bands on the mattress support. These belts or bands surround the mattress as well as the mattress support completely. In other known fastening devices toggle locks are used that are connected with the mattress. The toggle locks can extend through the interstices of a slatted frame that serves as mattress support and can be rotated below the slatted frame such that the toggle extends below two adjacent slats of the slatted frame and thereby fastens the mattress on the slatted frame. 
     In these known fastening devices the fastening and release of the mattress is time consuming. Particularly in nursery and therapy units the mattresses are frequently removed from the mattress support, cleaned and re-attached to the mattress support. This requires a lot of time that is then not available for the personnel for proper care of the patient. 
     DE 10 2005 118 235 A1 describes a fastening device that considers the drawbacks mentioned above and that provides an improved fastening of the mattress on the mattress support. However, the practical test has shown that also this known fastening device can be further improved. 
     Therefore it can be considered as an object of the present invention to provide a fastening device that on one hand ensures a simple release and attachment of the mattress to the mattress support and on the other hand reliably holds the mattress in each position on the mattress support and ensures a long lifetime. 
     BRIEF DESCRIPTION 
     Disclosed is a fastening device for attaching a mattress to a mattress support, wherein the mattress comprises a bottom side, a top side opposite the bottom side, two longitudinal sides extending in a longitudinal direction of the mattress and two transverse sides extending in a transverse direction of the mattress, at least two first plate-shaped holding parts that are arranged with a transverse distance to each other in the transverse direction of the mattress and having at least one second plate-shaped holding part that is larger in the transverse direction of the mattress than half a width of the mattress, wherein the plate-shaped holding parts are arranged at the mattress, multiple first fastening elements and multiple second fastening elements that project from the bottom side of the mattress and comprise a fastening head with a distance to the bottom side of the mattress, wherein at least one first fastening element is attached to each of the at least two first plate-shaped holding parts and wherein multiple second fastening elements are attached to the at least one second plate-shaped holding part, and multiple first holding recesses and multiple second holding recesses at the mattress support, each comprising an insertion opening and a holding slot adjoining thereto, wherein an outer dimension of the insertion opening is larger than an outer dimension of the fastening head such that the fastening head can be inserted in the assigned insertion opening and wherein a slot width of the holding slot is smaller than the outer dimension of the fastening head. 
     The fastening device is configured to attach a mattress to a mattress support. The mattress has a bottom side, a top side opposite the bottom side, two longitudinal sides extending in a mattress longitudinal direction and two transverse sides extending in a mattress transverse direction. The mattress longitudinal direction and the mattress transverse direction are orientated orthogonal to each other. The longitudinal sides and the transverse sides connect the bottom side with the top side of the mattress respectively. 
     The fastening device comprises at least two first plate-shaped holding parts and at least one second plate-shaped holding part. The two first plate-shaped holding parts are arranged with transverse distance to each other in mattress transverse direction. They are particularly identically configured and can be configured as a square or rectangle for example. The at least one second plate-shaped holding part has a larger width in mattress transverse direction than the first plate-shaped holding part and comprises a width that is larger than the half mattress width in mattress transverse direction. Preferably the width of the at least one second plate-shaped holding part has an amount of 70% to 90% of the mattress width in mattress transverse direction. 
     All of the plate-shaped holding parts are attached to the mattress and are arranged between two directly adjacent layers of the mattress in a preferred embodiment. The layers of the mattress can be glued to each other such that the plate-shaped holding parts are firmly anchored in the mattress. 
     Preferably the plate-shaped holding parts consist of plastic and can be manufactured by extrusion. In a preferred embodiment the plate-shaped holding parts consist of polyethylene. 
     Preferably each plate-shaped holding part is formed by one respective integral holding plate that is configured without seams or joints. The holding plate has preferably a thickness of less than 5 mm and in one embodiment a thickness of 3 mm. The first holding plates have a surface area in their extension plane of at least 100 cm 2  or at least 200 cm 2 . In an embodiment the first holding plates have a surface area of 225 cm 2  and are, for example, configured as square-shaped holding plates with an edge length of 15 cm. The at least one second holding plate or the only second holding plate has at least a surface area of 800 cm 2  or 1000 cm 2 . In one embodiment the second holding plate has a surface area of 1200 cm 2  and is, for example, configured as a rectangular-shaped holding plate with a width in mattress transverse direction of 80 cm and a length in mattress longitudinal direction of 15 cm. 
     The fastening device further comprises multiple first fastening elements and multiple second fastening elements. All fastening elements project from the bottom side of the mattress and extend through at least one part or layer of the mattress. They are connected by an inner end with one assigned plate-shaped holding part respectively and have a fastening head at the opposite outer end respectively that is arranged with distance to the bottom side of the mattress. Exactly one first fastening element or at least one first fastening element is attached at each first plate-shaped holding part respectively. Multiple second fastening elements are attached at the at least one second plate-shaped holding part respectively. Preferably one single second plate-shaped holding part is provided on which all of the second fastening elements are attached. 
     The mattress support is provided with multiple first and multiple second holding recesses. Each holding recess has an insertion opening and a holding slot adjoining the insertion opening. The insertion opening has an outer dimension that is larger than the outer dimension of the assigned fastening head of a respective fastening element. The fastening head can thus be inserted into the insertion opening. A width of the holding slot that is measured transverse to its extension direction is smaller than the outer dimension of the fastening head. After the insertion the fastening head can be moved out of the insertion opening such that the respective fastening element extends below the holding slot of the holding recess by means of the fastening head and thus locks the mattress to the mattress support. 
     The fastening elements form two groups according to the invention. The first fastening elements are arranged at separate plate-shaped holding parts. In the area in which the first fastening elements or the first plate-shaped holding parts are arranged in the mattress, the mattress can be deformed, particularly in mattress transverse direction. In the area in which the second fastening elements or the at least one second plate-shaped holding part is present, the mattress can be deformed in mattress transverse direction only in a limited manner due to the relatively large surface or width of the at least one second plate-shaped holding part, however, comprises in this area a very stable attachment of the mattress to the mattress support. The mattress is only able to move slightly away from the mattress support in the area of the at least one second plate-shaped holding part, which is particularly advantageous, if the mattress support takes a seat position. Preferably the at least one second plate-shaped holding part is arranged with the second fastening elements in a support section of the mattress support forming a lower leg section. Specifically here it is important to retain the mattress to the mattress support so that the patient can place the feet on the floor for the purpose of standing up without being impeded by the mattress. Thereby the lower leg section of the mattress support shall be particularly inclined relative to the vertical away from the feet below the central section of the mattress support serving to seat and the mattress shall, however, be reliably held thereon. In doing so, it is allowed for the patient to place the feet sufficiently far backward on the floor in order to bring the center of gravity above the feet and to be able to stand up. 
     It is preferred that the holding slots of the first holding recesses extend in a support transverse direction and/or that the holding slots of the second holding recesses extend in a support longitudinal direction. The support transverse direction and the support longitudinal direction are orientated orthogonal to each other. If the attachment between the mattress and the support is established, the support transverse direction corresponds to the mattress transverse direction and the support longitudinal direction corresponds to the mattress longitudinal direction. 
     Particularly the first plate-shaped holding parts are arranged with transverse distance to each other in mattress transverse direction, wherein this transverse distance is preferably as large as the slot length of a holding slot of one of the first holding recesses and is in one embodiment larger than the half mattress width in mattress transverse direction. Due to this sufficiently large transverse distance, an elastic deformability of the mattress in mattress transverse direction is ensured in the area of the at least two first plate-shaped holding parts. 
     In a preferred embodiment exactly one first fastening element is attached on each first plate-shaped holding part and further preferably exactly one second plate-shaped holding part is present to which all of the second fastening elements are attached. 
     The width of the at least one second plate-shaped holding part can be at least 70% or at least 80% or at least 90% of the mattress width. The wider the at least one second plate-shaped holding part is, the better the mattress is fixed in this area. The at least one second plate-shaped holding part has particularly a width that is smaller than the mattress width. 
     It is preferred that two of the fastening elements have an element distance in the non-deformed initial position of the mattress in mattress longitudinal direction and/or mattress transverse direction that is different from an opening distance that the insertion openings of the assigned holding recesses comprise. Due to this configuration, the fastening elements extend below the holding recesses in the area of the respective holding slots, because the mattress tries to takes its non-deformed initial position. By elastically deforming of the mattress, the fastening heads can be arranged in the area of the insertion openings and the mattress can be attached to the mattress support or can be released from the mattress support. 
     It is also advantageous that two first fastening elements comprise a first element distance in mattress transverse direction. Thereby the insertion openings of the first holding recesses can have a first opening distance in a support transverse direction of the mattress support that is smaller than the first element distance. 
     It is further advantageous that the second fastening elements have a second element distance to the first fastening elements in mattress longitudinal direction. Thereby the insertion openings of the second holding recesses can have a second opening distance in a support longitudinal direction to the insertion openings of the first holding recesses that is smaller than the second element distance. 
     The mattress support is preferably arranged at a base part. The mattress support has preferably a main part and a foot part. The foot part is particularly arranged separately from the main part at the base part or a bed frame. The main part of the mattress support can be pivotable about a pivot axis S by means of a pivot device and/or can be movable parallel to the pivot axis or linearly shiftable. The pivot axis is substantially orientated in vertical direction or orthogonal to the ground on which the base part or the bed frame is installed. 
     It is preferred, if the mattress support and particularly the main part of the mattress support comprises at least three support sections, wherein two directly adjacent support sections are connected with each other by means of a hinge arrangement in pivotable manner. In an embodiment the mattress support comprises at least one back section, a central section that is connected with the back section in a hinged manner, as well as a lower leg section. The lower leg section can be connected with the central section in a hinged manner. Alternatively it is also possible that an additional thigh section, as a further support section, is present between the central section and the lower leg section that is connected with the central section and the lower leg section in a hinged manner. 
     It is preferred that the first holding recesses and the second holding recesses are assigned to different support sections. Preferably all of the first holding recesses can be arranged at one single support section and all of the second holding recesses can be arranged at one other support section. Preferably the second holding recesses are arranged at the lower leg section and the first holding recesses are arranged at the central section and/or the thigh section. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred embodiments of the invention are derived from the dependent claims, the description and the drawings. In the following preferred embodiments of the invention are explained in detail with reference to the attached drawings. The drawings show: 
         FIG. 1  a schematic illustration of a mattress support in a top view, wherein the mattress support is in a lying position, 
         FIG. 2  a schematic top view of a bottom side of a mattress with a supplement mattress in its undeformed initial condition, 
         FIG. 3  a perspective view of the mattress of  FIG. 2 , 
         FIG. 4  a top view on the bottom side of the mattress of  FIG. 3 , 
         FIG. 5  a schematic principle illustration of a bed, wherein the mattress support with the mattress attached thereon is in a seat position, 
         FIG. 6  a schematic sectional partial illustration of a mattress with an attached fastening element, 
         FIG. 7  the mattress and the fastening element according to the illustration of  FIG. 6 , wherein the fastening element is arranged in a holding slot of a holding recess and 
         FIG. 8  an embodiment of a constructive configuration of a fastening element. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 5  shows in a highly schematical manner a bed in the form of a nursery bed  10  with a bed frame  11 . A base part  12  is part of the bed frame  11  or is surrounded or supported by the bed frame  11 . The base part  12  has a stand  13  by means of which the base part  12  can be placed on a ground in the embodiment. According to the embodiment, the bed frame has side elements  13  arranged at the sides that surround the base part  12 . 
     The bed frame  11  and according to the example the base part  12  support a mattress support  16 . The mattress support  16  has a main part  17  and a foot part  18 . According to the example the foot part  18  is arranged on the bed frame  11  and immovable relative to the bed frame. The main part  17  is separated from the foot part  18  and movable relative to the foot part  18 . In the embodiment the main part  17  of the mattress support  16  is supported on the base part  12 . For moving the main part  17  the base part  12  comprises a pivot device  19  and lift device  20 . By means of the pivot device  19  the mattress main part  17  can be pivoted about a pivot axis S. In the embodiment the pivot axis S extends substantially in vertical direction V or orthogonal to a ground, on which the bed frame  11  or the base part  12  is placed. By means of the lift device  20 , the main part  17  of the mattress support  16  can be lifted and lowered parallel to the pivot axis S and according to the example in vertical direction V. 
     In the embodiment the mattress support  16  comprises multiple support sections  24  that are connected with each other in a hinged manner and can be angled relative to each other. In the embodiment the main part  17  of the mattress support  16  is divided in multiple and according to the example in at least three or four support sections  24 . Two directly adjacent support sections  24  are connected with each other by a hinge arrangement  25  in a hinged manner in each case. The hinge axes G of the hinge arrangements  25  extend parallel to each other in a support transverse direction QT of the mattress support  16  or the main part  17  of the mattress support  16  ( FIG. 1 ). The hinge axes G are orientated orthogonal to the pivot axis S. 
     The hinge arrangements  25  as well as the lift device  20  and the pivot device  19  can be operated by a motor and, for example, by an electric motor. The operation by an electric motor can be controlled by a non-illustrated operating device. As an alternative thereto it would also be possible to operate one or more of these devices mechanically with a handle, e.g. the lift device  20  could be controlled or operated by means of a foot pedal and/or the hinge arrangements  25  could be controlled or operated by means of a hand lever in each case. 
     By means of the hinge arrangements  25 , the support sections  24  can be brought in a lying position I of the mattress support  16  illustrated in  FIG. 1 , in which the support sections  24  are orientated substantially parallel to a common plane, wherein this plane is formed by the support transverse direction QT and a support longitudinal direction LT that is orientated orthogonal thereto. One or more support sections  24  can be moved out of this lying position I by tilting about a hinge axis G, e.g. in a seat position II ( FIG. 5 ). 
     In the embodiment illustrated in  FIG. 5  the main part  17  comprises four support sections  24 : a back section  26 , a central section  27 , a thigh section  28  and a lower leg section  29 . The back section  26  is connected with the central section  27  by means of a hinge arrangement  25  in a hinged manner. The thigh section  28  is connected with the central section  27  in a hinged manner by means of a hinge arrangement  25  and is connected with the lower leg section  29  in a hinged manner by means of a further hinge arrangement  25 . The thigh section  28  can also be omitted as an option, wherein the lower leg section  29  is connected with the central section  27  directly by means of a hinge arrangement  25  in this case. 
     In the seat position II of the mattress support  16  or the main part  17  of the mattress support  16  shown in  FIG. 5  the back section  26  is raised similar to the back of a chair. The adjoining central section  27  extends substantially orthogonal to the pivot axis S or to the vertical direction V similar to a seating surface of a chair. In the exemplary seat position the thigh section  28  extends the central section  27  substantially horizontally or orthogonal to the pivot axis S. In the seat position II the lower leg section  29  extends downward in vertical direction V and according to the example concurrently backward. In doing so, the free end of the lower leg section  29  opposite the thigh section  28  is arranged below a support section  24  (e.g. thigh section  28  or central section  27 ) forming the seating surface. The plane in which the lower leg section  29  extends encloses an angle α with the vertical direction V that is larger than zero and has, according to the example, an amount of at least 10° or at least 15° or at least 20°. Due to this orientation of the lower leg section  29 , it is possible for a patient  30  to place his/her feet  31  on the ground in a manner such that the heel is located below the thigh  32 . A lower leg  33  of the patient  30  thereby extends inclined with regard to the vertical direction V. In this position standing up is facilitated for the patient  30 , because he can shift his upper body more simply forward above the feet  31 . 
     In a modified embodiment the back section  26  of the main part  17  can be divided by means of a further hinge arrangement  25  such that in addition a further support section  24  is present that can form a head section. 
     In order for the main part  17  of the mattress support  16  to be brought in the seat position II shown in  FIG. 5 , the bed frame  11  can comprise at one longitudinal side of the bed frame  11  a side element  14  that can be at least partly lowered or moved. For example, at least one side element  14  can be separated into two parts, wherein the other part can be moved in vertical direction V relative to the lower part of the side element  14 . In doing so, the central section  27  and/or the thigh section  28  can extend beyond the respective side element  14  of the bed frame  11  in the seat position II of the mattress support  16  in order to allow the patient  30  to stand up adjacent to the bed frame  11 . 
     The mattress support  16  is configured to support a mattress  40 . The mattress  40  comprises a bottom side  41  facing the mattress support, a top side  42  opposite the bottom side  41 , two longitudinal sides  43  extending in a mattress longitudinal direction LM and two transverse sides  44  extending in a mattress transverse direction QM. According to the example, the mattress  40  is supported by the main part  17 . A supplement mattress  45  is configured separately from the mattress  40  and is placed on the foot part  18  of the mattress support  16 . The supplement mattress  45  thus serves as support for the feet of the patient, if the mattress support  16  is in the lying position I. 
     The mattress  40  and according to the example the supplement mattress  45  have a mattress width BM in mattress transverse direction QM. The length of the mattress  40  in mattress longitudinal direction LM is remarkably longer than that of the supplement mattress  45 . 
     For releasably attaching the mattress  40  on the mattress support  16  or the main part  17  of the mattress support  16 , a fastening device  50  is provided. The fastening device  50  comprises first fastening elements  51  and second fastening elements  52  on the mattress side, as well as first holding recesses  53  and second holding recesses  54  on the support side. The fastening elements  51 ,  52  project from the bottom side  41  of the mattress  40 . The first fastening elements  51  are attached at an assigned first plate-shaped holding part  55  and the second fastening elements  52  are attached at one assigned second plate-shaped holding part  56  respectively. In the embodiment the plate-shaped holding parts  55 ,  56  are configured as holding plate  57  in each case that is integrally made without seam or joint from a continuous material. For example, the holding plate  57  is configured as plastic plate and consists preferably of polyethylene. The holding plate  57  has a plate thickness P in a height direction H orthogonal to the mattress longitudinal direction LM and orthogonal to the mattress transverse direction QM of some millimeters and preferably less than 5 mm. In the embodiment the plate thickness P has an amount of some millimeters and preferably less than 5 mm. In the embodiment the plate thickness P has an amount of 3 mm ( FIG. 6 ). 
     By means of the plate-shaped holding parts  55 ,  56 , the fastening elements  51 ,  52  are attached to the mattress  40 . According to the example, this is realized in that the plate-shaped holding parts  55 ,  56  are arranged in the inside of the mattress  40 . It is apparent from  FIGS. 6 and 7  that the mattress  40  is made from multiple layers  40   a . Between two layers  40   a  that directly abut against each other, the respective plate-shaped holding part  55 ,  56  can be arranged. The two layers  40   a  can be glued subsequently and the holding parts  55 ,  56  can be fixed in between. Preferably all of the holding parts  55 ,  56  are arranged in a common plane, according to the example adjacent to the lower most layer  40   a  of the mattress  40  that comprises the bottom side  41 . 
     The fastening elements  51 ,  52  extend through the lower most layer  40   a . The fastening elements  51 ,  52  have a fastening head  60  respectively that is arranged with distance to the bottom side  41  of the mattress  40 . The fastening head  60  is located at the outer end  61  or forms the outer end  61  of the fastening element  51 ,  52 . The fastening element  51 ,  52  is attached to the assigned holding plate  57  by an inner end  62  opposite the outer end  61 . Adjoining the inner end  62  the fastening element  51 ,  52  has a shank  63  that extends through the mattress  40  and according to the example the lower most layer  40   a  of the mattress  40 . 
     An abutment part  64  of the fastening element  51 ,  52  is supported on the bottom side  41 . The fastening element  51 ,  52  has a neck part  65  between the abutment part  64  and the fastening head  60 . The neck part  65  has a neck diameter DH orthogonal to the height direction. The fastening head  60  has a head diameter DK orthogonal to the height direction. The head diameter DK is larger than the neck diameter DH. The diameter of the abutment part  64  can correspond to the head diameter DK. 
     In the illustrated embodiment the fastening head  60 , the neck part  65 , as well as the abutment part  64  have a circular contour respectively with view in height direction H. Different thereto the contour could also have arbitrary other shapes. Instead of the diameter, the mentioned parts then have a respective dimension in mattress transverse direction QM and in mattress longitudinal direction LM. At least the cross-sectional area of the neck part is also in this case smaller than that of the fastening head  60 . 
       FIG. 8  illustrates an embodiment for a fastening element  51 ,  52 . The fastening element  51 ,  52  comprises a screw  66  with a screw head  67  that forms the inner end  62 . The screw  66  is inserted through a hole in the assigned holding plate  57  and attached to the holding plate  57  by means of the screw head  67  and a locking nut  68 . Thereby the holding plate  57  is engaged in a clamping manner between the screw head  67  and the locking nut  68 . 
     Adjoining the locking nut  68  a first sleeve  69  is mounted on the screw  66  in the area of the shank  63 . The locking nut  68  and the first sleeve  69  form the shank  63 . The abutment part  64  abuts against the first sleeve  69 , wherein the abutment part  64  is formed by a washer  70  according to the example. The neck part  65  is formed by a second sleeve  71  that is mounted on the screw  66 . The second sleeve  71  extends between the abutment part  64  and the fastening head  60 . According to the example, the fastening head  60  is also formed by a washer  70  that can be identical with the washer  70  of the abutment part  64 . 
     In the area of the outer end  61  a further locking nut  68  is screwed onto the screw  66  that locks the sleeves  69 ,  71  and the washer  70 . As an option, a cap  62  can be mounted on the end of the screw  66  opposite the screw head  67 , wherein the cap can have a half-spherical shape according to the example. 
     In the embodiment all of the fastening elements  51 ,  52  are configured identically and can have, e.g. a configuration shown in  FIG. 8  and explained above. 
     As is illustrated in  FIGS. 2-4  exactly one first fastening element  51  is attached to each first plate-shaped holding part  55 . According to the example, two first plate-shaped holding parts  55  are provided. It is further apparent that only one single second plate-shaped holding part  56  is provided to which all of the second fastening elements  52  (according to the example, three second fastening elements  52 ) are attached. 
     As shown in  FIG. 4 , two first plate-shaped holding parts  55  are provided that have a transverse distance QA in mattress transverse direction QM. According to the example, the transverse distance QA is at least as large as the half mattress width BM in mattress transverse direction QM. The transverse distance QA is larger than a first width B 1  of the first plate-shaped holding parts  55  in mattress transverse direction QM. The first plate-shaped holding parts  55  have a first length L 1  in mattress longitudinal direction LM. According to the example, the first length L 1  is equal to the first width B 1 . The area of the first plate-shaped holding parts  55  parallel to the plain spanned by the mattress longitudinal direction LM and the mattress transverse direction QM comprises a surface area of at least 100 cm 2  or at least 200 cm 2 . According to the example, the surface area has an amount of about 225 cm 2 . 
     Each first plate-shaped holding part  55  has a longitudinal edge  55   a  that is orientated parallel to the adjacent longitudinal side  43  of the mattress  40  respectively. Due to this straight longitudinal edge  55   a , first plate-shaped holding parts can be arranged close to the respective longitudinal side  43  of the mattress  40  and in addition, cover a sufficiently large surface area. In addition, the transverse distance QA can be selected sufficiently large. 
     The plate-shaped holding part  56  has a second width B 2  that is larger than the half mattress width BM and has an amount of particularly 70% or 80% or 90% of the mattress width BM. The second plate-shaped holding part  56  has a second length L 2  in mattress longitudinal direction LM that is equal to the first length L 1  according to the example. The second plate-shaped holding part  56  has a longitudinal edge  56 a adjacent to each longitudinal side  43  of the mattress  40  that extends parallel to the adjacent longitudinal side  43 . Adjacent to a transverse side  44  of the mattress  40  the second plate-shaped holding part  56  has a transverse edge  56   b  that extends parallel to the transverse side  44 . Parallel to the plane that is spanned by the mattress longitudinal direction LM and the mattress transverse direction QM, the second plate-shaped holding part  56  has a surface area of at least 800 cm 2  or at least 1,000 cm 2  or at least 1,200 cm 2 . According to the example, the second width B 2  has an amount of 80 cm when the mattress width BM has an amount of 100 cm. 
     As is apparent from  FIG. 4 , each longitudinal edge  56   a  of the second plate-shaped holding part  56  has a lateral distance X from the respective directly adjacent longitudinal side  43  of the mattress  40 . The lateral distance X has an amount of preferably at most 15 cm and in the embodiment at most 10 cm. The transverse edge  56   b  of the second plate-shaped holding part  56  can have a lateral distance to the adjacent transverse side  44  of the mattress  40  analog thereto, the amount of which can be selected equal to the lateral distance X or smaller. 
     The longitudinal edges  55   a  of the first plate-shaped holding parts  55  have a distance to the directly adjacent longitudinal side  43  of the mattress  40  respectively that corresponds at most to the lateral distance X and is smaller according to the embodiment. 
     In modification to the illustrated embodiment the plate-shaped holding parts  55 ,  56  or the holding plates  57  can also have another contour than a square or rectangular contour. The square or rectangular contours have the advantage that the longitudinal edges  55   a ,  56   a  or the transverse edges  56   b  of the plate-shaped holding parts  55  or  56  can be arranged very closely to the respective longitudinal side  43  or transverse side  44  of the mattress  40 . 
     It is also apparent from  FIG. 4  that the second fastening elements  52  are not centrally arranged in mattress longitudinal direction, but are arranged offset to the central axis A of the second plate-shaped holding part  56  and according to the example, are offset from the central axis A away from the closer transverse side  44  of the mattress  40  about a longitudinal offset DL. 
     The two outer second fastening elements  52  in mattress transverse direction QM are farther away from the adjacent longitudinal side  43  about a transverse offset DQ than the respective outer first fastening elements  51  in mattress transverse direction QM. 
     Preferably exactly three plate-shaped holding parts  55 ,  56  or holding plates  57 , two first fastening elements  51  and at least two second fastening elements  52  and according to the example, exactly three second fastening elements  52  are provided. It is also preferred, if the plate-shaped holding parts  55 ,  56  and the fastening elements  51 ,  52  are arranged symmetrically relative to a longitudinal central plane ME extending through the mattress  40 . 
     Based on the illustration in  FIG. 2 , it is apparent that the two first fastening elements  51  have a first element distance E 1  in mattress transverse direction QM that is measured from center to center respectively. The second fastening elements  52  have a second element distance E 2  from the first fastening elements  51  in mattress longitudinal direction LM that is also measured from center to center of the fastening elements  51 ,  52 . 
     In the mattress support  16  and according to the example the main part  17 , multiple holding recesses are provided, wherein for each of the first fastening elements  51  a first holding recess  77  and for each second fastening element  52  a second holding recess  78  is provided. Each holding recess  77 ,  78  has an insertion opening  79  and a holding slot  80  adjoining the insertion opening. The insertion opening  79  have an insertion diameter DE that is slightly larger than the head diameter DK of the fastening elements  51 ,  52 . In doing so, the fastening head  60  can be inserted through the insertion opening  79 . A slot width BS of the holding slot  80  is smaller than the insertion diameter DE and smaller than the head diameter DK. The slot width BS is larger than the neck diameter DH of the fastening elements  51 ,  52 . In doing so, the fastening element  51 ,  52  can be inserted with its respective neck part  65  in the holding slot  80  and can be shifted along the holding slot  80 . Thereby the fastening head extends below a respective support plate  81  of the mattress support  16  in which the respective holding recess  77 ,  78  is arranged. The holding recesses  77 ,  78  extend completely through the respective support plate  81 . 
     The holding slots  80  of the two first holding recesses  77  extend in support transverse direction QT. The two first holding recesses  77  are arranged such that the insertion openings  79  are arranged inward at the respective holding recess  77  and thus are arranged at adjacent ends and that the holding slots extend away outwardly from the respective insertion opening and away from the respective other holding recess  77  so-to-speak. 
     The second holding recesses  78  respectively have a holding slot  80  that extends in support longitudinal direction LT of the mattress support  16 . The holding slots  80  extend originating from the respective insertion opening  79  away and according to the example, away from the first holding recesses  77 . 
     The support plate  81  with the first holding recesses  77  is located in the central section  27  of the mattress support  16  according to the example and the support plate  81  with the second holding recesses  78  is located in the lower leg section  29  of the mattress support  16  according to the example. In modification to the illustrated embodiment, a support plate  81  with first holding recesses  77  could be arranged additionally or alternatively also in the thigh section  28 . It is preferred, if the support plate  81  with the first holding recesses  77  is arranged as close as possible or directly adjoining the hinge arrangement  25  that connects the central section  27  with the back section  26  in a hinged manner. In each case the first holding recesses  77  and the second holding recesses  78  are not provided in the same support sections  24 . 
     As apparent from  FIGS. 1 and 2 , the insertion opening  79  of the first holding recesses  77  have a first opening distance O 1  in support transverse direction QT that is measured from center to center of the insertion openings  79  respectively. The first opening distance O 1  is smaller than the first element distance E 1  of the assigned first fastening elements  51 . 
     The insertion opening  79  of the second holding recesses  78  have a second opening distance O 2  from the insertion opening  79  of the first holding recesses  77  in support longitudinal direction LT. The second opening distance O 2  is smaller than the second element distance E 2  between the first fastening elements  51  and the second fastening elements  52  in support longitudinal direction LT. 
     The holding slots  80  of the first holding recesses  77  have a slot length LS starting from the insertion opening  79  up to their opposite end. The transverse distance QA between the two first plate-shaped holding parts  55  is at least as large as the slot length LS. Preferably the slot length LS of all of the holding slots  80  of all of the holding recesses  77 ,  78  is equal. The slot length LS is larger than the diameter DE of the insertion openings  79 . 
       FIG. 2  also shows another optional configuration for fastening the second fastening elements  52  at the mattress  40 . With distance to the second plate-shaped holding part  56  or the holding plate  57 , a strip  82  can be placed on the bottom side  41  of the mattress  40 . The strip  82  can be manufactured, e.g. from plastic and can have through-holes for all of the second fastening elements  52 . The strip  82  can be used as common abutment part  64  of the second fastening elements  52  or can be placed in addition between the bottom side  41  of the mattress and the respective abutment parts  64 . 
     The fastening of the mattress  40  to the main part  17  of the mattress support  16  can be carried out as described in the following for example: 
     For attaching the first fastening elements  51  to the first holding recesses  77 , first the fastening head  60  of a first fastening element  51  is inserted through the assigned insertion opening  79  and the neck part is inserted in the holding slot  80  and shifted away from the insertion opening  79 . The mattress  40  is compressed in mattress transverse direction QM until also a fastening head  60  of the respective other first fastening element  51  can be inserted through the assigned insertion opening  79 . If the elastic deformation of the mattress  40  is then released, the mattress  40  urges the two first fastening elements  51  away from each other, such that the neck parts  65  extend through the respective holding slot  80  and the fastening head  60  extend beyond the support plate  81  on the side of the support plate  81  opposite the bottom side  41  of the mattress  40 . 
     Subsequently, the end of the mattress  40  assigned to the lower leg section  29  and comprising the second fastening elements  52  can be moved in mattress longitudinal direction LM by elastic deformation or bending of the mattress  40  such that the fastening heads  60  of the second fastening elements  52  can be inserted in the insertion opening  79  of the second holding recesses  78 . If the mattress  40  is then released, the force created due to the elastic deformation of the mattress  40 , urges the neck parts  65  in the associated holding slots  80  and the fastening heads  60  can extend beyond the support plate  81  having the second holding recesses  78  in the area of the holding slots  80 . The mattress  40  is then releasably attached to the mattress support  16 . 
     For releasing the mattress  40  from the mattress support  16 , it can be proceeded in reverse order. By shifting of the fastening elements  51 ,  52  along the holding slots  80 , the fastening heads can be arranged in the area of the respective insertion opening  79  and removed through the insertion opening  79  from the mattress support  16 . 
     The order in which the first and second fastening elements  51 ,  52  can be arranged on the mattress support  16  or in the respective assigned holding recess  77  or  78  or else can be removed therefrom, can be modified. For example, it is possible to first arrange the second fastening elements  52  in the second holding recesses  78  and subsequently arrange the first fastening elements  51  in the first holding recesses  77 . 
     As apparent from  FIG. 5 , the mattress  40  is fixed on the main part  17  of the mattress support  16  by means of the fastening elements  51 ,  52 . Because of the raising of the back section  26  and the fixing of the mattress  40  in the range of the central section  27 , an additional fixation in the back section  26  can be omitted, because the mattress  40  presses against the back section  26  due to the elastic deformation. A fixing of the mattress  40  by means of the two first fastening elements  51  with the first element distance E 1  is sufficient in this area. Because of the bend in the mattress  40  in the transition region between the central section  27  and the back section  26 , the mattress  40  tends not to camber at this location. 
     The fixing of the mattress  40  in the area of the lower leg section  29  is of particular importance in order not to impede the lower legs  33  and the feet  31  of the patient  30 . Particularly because the lower leg section  29  is pivoted below the thigh section  28  or the central section  27  (angle α relative to the vertical V), high elastic deformation forces act on the mattress  40  in the area of the lower leg section  29 , the mattress  40  tends to release itself in this area from the lower leg section. Because the second fastening elements  52  are commonly attached at the second plate-shaped holding part  56  and the latter preferably extends nearly over the whole mattress width BM, these forces are supported via a sufficiently large area in the mattress  40  and avoid ripping of the second fastening elements  52  of the mattress  40 . In addition, camber of the mattress  40  in the area of the edges between the longitudinal sides  43  and the transverse sides  44  can be avoided, because the mattress  40  is stiffened in this area by the second plate-shaped holding part  56 . 
     The stiffening of the mattress  40  by the second plate-shaped holding part  56  is uncritical for the lying comfort. The lower legs  33  of the patient  30  lye on the mattress  40  in this section and thus only a low weight force acts on the top side  42  of the mattress  40 . On the contrary, the center of gravity of the patient  30  is located in the area of the first fastening elements  51 . There a sufficiently large transverse distance QA is selected between the first plate-shaped holding parts  55  in order to not or only marginally affect the lying comfort and in order to not effect a stiffening of the mattress  40  adversely influencing the lying comfort. However, a ripping of or breaking away of the first fastening elements  51  is avoided due to a sufficiently large area of the first plate-shaped holding parts  55 . The durability of the fastening device  50  or the mattress  40  is guaranteed. 
     The invention refers to a fastening device  50  for attaching a mattress  40  to a mattress support  16  or a bed, particularly a nursery bed  10  with such a fastening device  50 . The mattress support  16  comprises multiple support sections  24  that are connected with each other in a hinged manner. In the central section  27  of the mattress support  16  a support plate  81  with first holding recesses  77  is arranged. In a lower leg section  29  of the mattress support  16  a support plate  81  with second holding recesses  78  is arranged. First fastening elements  51  attached to the mattress are assigned to the first holding recesses and second fastening elements  52  attached to the mattress  40  are assigned to the second holding recesses  78 . The first fastening elements  51  are attached to at least two first plate-shaped holding parts  55  that are arranged under formation of a transverse distance QA on opposite sides of the mattress  40  in a mattress transverse direction QM. The second fastening elements  52  are preferably arranged at one single common second plate-shaped holding part  56  that extends along more than half of the mattress width BM in mattress transverse direction QM and preferably nearly along the whole mattress width EM. 
     LIST OF REFERENCE SIGNS 
       10  bed
 
 11  bed frame
 
 12  base part
 
 13  stand
 
 14  side element of bed frame
 
 16  mattress support
 
 17  main part
 
 18  foot part
 
 19  pivot device
 
 20  lift device
 
 24  support section
 
 25  hinge arrangement
 
 26  back section
 
 27  central section
 
 28  thigh section
 
 29  lower leg section
 
 30  patient
 
 31  foot of patient
 
 32  thigh of patient
 
 33  lower leg of patient
 
 40  mattress
 
 40   a  layer of mattress
 
 41  bottom side of mattress
 
 42  top side of mattress
 
 43  longitudinal side of mattress
 
 44  transverse side of mattress
 
 45  supplement mattress
 
 50  fastening device
 
 51  first fastening element
 
 52  second fastening element
 
 53  first holding recess
 
 54  second holding recess
 
 55  first plate-shaped holding part
 
 55   a  longitudinal edge of first plate-shaped holding part
 
 56  second plate-like holding part
 
 56   a  longitudinal edge of second plate-like holding part
 
 56   b  transverse edge of second plate-like holding part
 
 57  holding plate
 
 60  fastening head
 
 61  outer end of fastening element
 
 62  inner end of fastening element
 
 63  shank
 
 64  abutment part
 
 65  neck part
 
 66  screw
 
 67  screw head
 
 68  locking nut
 
 69  first sleeve
 
 70  washer
 
 71  second sleeve
 
 72  cap
 
 77  first holding recess
 
 78  second holding recess
 
 79  insertion opening
 
 80  holding slot
 
 81  support plate
 
 82  strip
 
I lying position
 
II seat position
 
α angle
 
A central axis
 
BM mattress width
 
B 1  first width
 
B 2  second width
 
BS slot width
 
DE insertion diameter
 
DH neck diameter
 
DK head diameter
 
DL longitudinal offset
 
DQ transverse offset
 
E 1  first element distance
 
E 2  second element distance
 
G hinge axis
 
H height direction
 
LM mattress longitudinal direction
 
LS slot length
 
LT support longitudinal direction
 
ME longitudinal central plane
 
O 1  first
 
O 2  second
 
P plate thickness
 
QA transverse distance
 
QM mattress transverse direction
 
QT support transverse direction
 
S pivot axis
 
V vertical direction
 
X lateral distance