Roll holder for receiving and holding film rolls and prestretching device for prestretching film, having a corresponding roll holder

Abstract

The invention relates to a roll holder (100) for receiving and holding film rolls (200) consisting of rolled-up film webs (220), wherein the roll holder (100) comprises the following: a roll receiving body (110), which can be inserted into a film roll (200); and a gripping mechanism (120), which extends through the roll receiving body (110) in an axial direction, wherein the gripping mechanism (120) comprises a holding device (130 for holding the film roll (200) in the axial direction, the holding device (130) being transferrable between a release position and a holding position, and wherein the gripping mechanism (120) comprises a release device (140) for transferring the holding device (130) into the release position, the release position (140) having an actuation element (141) that is displaceable in the axial direction and can be brought into contact with the holding device (130) in order to transfer the holding device (130) from the holding position into the release position. The invention also relates to a prestretching device for prestretching film, having a roll holder.

Description

[0001] Roll holder for picking up and holding film rolls and pre-stretching device for pre-stretching film with a corresponding roll holder

[0002] Technical area

[0003] The invention relates to a roll holder for receiving and holding film rolls from rolled-up film webs, in particular stretch film webs. Furthermore, the invention relates to a pre-stretching device for pre-stretching film, in particular stretch film, with a corresponding roll holder.

[0004] State of the art

[0005] When grouping and assembling items, such as beverage containers, or entire bundles of items, film is often used as packaging material. Film is also often used to bind entire pallet loads together and on the pallet.

[0006] Today's wrapping machines essentially consist of a platform that supports the items or packages on a pallet and a structure that supports the film feeder. The platform can be rotating or fixed. The structure can basically consist of a simple vertical column on which a unit equipped with the aforementioned feeder slides in both directions (with a rotating platform), or it can have horizontal elements, such as arms, that rotate around the pallet to be wrapped (usually with a fixed platform). The film feeder typically consists of a rotatably mounted film reel and several rollers that serve to guide and feed the film.

[0007] In addition, today's wrapping machines often use driven pre-stretching devices when using cold stretch film or stretch film.

[0008] These pre-stretching devices allow for an increase in the stabilizing effect of the film with a proportional reduction in the film's weight. The pre-stretching devices typically comprise at least one pair of independently driven rollers to allow independent rotational speeds. Furthermore, these pre-stretching devices also comprise roll holders for receiving and holding film rolls.

[0009] Generally, film rolls must be replaced with new ones at regular intervals when the rolled film web runs dry. To do this, the old film roll must be removed from the roll holder and the new one placed on the roll holder. A changing mechanism is therefore required.

[0010] All currently known change mechanisms are quite complex in design and difficult to operate. This is especially true for automatic change mechanisms.

[0011] Overall, it would therefore be desirable to provide a roll holder that allows for easy, especially manual, changing of the film roll. Description of the invention

[0012] The invention is therefore based on the object of providing a roll holder that eliminates the above-mentioned problems and disadvantages of the prior art. Furthermore, it is the object of the present invention to provide a pre-stretching device for pre-stretching film that also eliminates the above-mentioned problems and disadvantages of the prior art. These objects are achieved by the subject matter of the independent claims. Further possible embodiments of the invention are specified in particular in the dependent claims.

[0013] The solution according to the invention consists in particular in specifying a roll holder for receiving and holding film rolls from rolled-out film webs, in particular stretch film webs. The roll holder is therefore designed to receive and hold film rolls. The roll holder has a roll receiving body. The roll receiving body can basically have a preferably at least substantially cylindrical outer shape. The roll receiving body is designed to receive a film roll. For this purpose, the roll receiving body can be inserted into the film roll, in particular a film roll body thereof. The film roll body is here a preferably cylindrical bearing element onto which the film roll is rolled up. The film roll body or the film roll is designed as a hollow cylinder. Due to the recess in the hollow cylinder, the roll receiving body can be inserted or plugged into the film roll.

[0014] Furthermore, the roll holder has a gripping mechanism that extends in an axial direction through the roll receiving body. The gripping mechanism preferably extends completely, i.e., from one end to the other end, through the roll receiving body.

[0015] The gripping mechanism is particularly designed to fix a film roll on the roll holder and to release it. The gripping mechanism has a holding device for holding the film roll in the axial direction. The holding device is designed to be transferable between a release position and a holding position. In the release position, the gripping mechanism or the holding device releases the film roll. The film roll can then be removed from the roll holder. In the holding position, the gripping mechanism or the holding device holds the film roll on the roll holder. The film roll cannot then be removed from the roll holder or cannot be removed without damaging it.

[0016] Furthermore, the gripping mechanism has a release device for moving the holding device into the release position. The release device thus serves to release or remove a film roll from the roll holder.

[0017] The release device further comprises an actuating element, in particular a manual one. The actuating element is designed to be displaceable in the axial direction, in particular relative to the holding device. Furthermore, the actuating element can be brought into contact with the holding device in order to move the holding device from the holding position to the release position. The actuating element thus serves to actuate the release device in order to move the holding device from the holding position to the release position, i.e., to release a film roll from the roll holder.

[0018] The inventive solution creates a simple and reliable manual mechanism for changing film rolls. The holding device, which holds the film roll in the axial direction, allows the film roll to be securely attached to the roll holder. At the same time, the holding device can be easily released using the release device.

[0019] The gripping mechanism preferably has a plurality of corresponding holding devices. Independently of this and furthermore preferably, the actuating element is preloaded. For this purpose, the gripping mechanism has a preloading element designed to preload the actuating element in the axial direction. In particular, the preloading element serves to preload the actuating element downward.

[0020] The relative terms "bottom" and "top" refer to the roll receiving body. "Bottom" refers to the lower section of the roll receiving body, which is first inserted into the film roll. The term "top" refers to the opposite, upper section of the roll receiving body, toward which the film roll is pushed. With respect to the actuation direction of the actuating element, the actuation direction is from bottom to top.

[0021] Stretch film is a particularly highly stretchable plastic film that can be wrapped around items. The elastic recovery force of the stretch film then holds the items together particularly tightly. In contrast, shrink film, for example, is wrapped loosely around an object and shrinks under the influence of heat.

[0022] According to an advantageous development of the invention, the holding device has a holding section which forms an axial stop for the film roll in the holding position of the holding device.

[0023] The holding section is thus designed to hold the film by means of an axial contact, in particular to the roll receiving body. This prevents the film roll from moving axially in the direction of the holding section and remains on the roll receiving body.

[0024] In an advantageous development of the invention, the holding section is arranged in a radially inner position when the holding device is arranged in the release position. Furthermore, the holding section is arranged in a radially outer position when the holding device is arranged in the holding position. The term "radial" refers to the axis of rotation of the film roll. The axis of rotation of the film roll preferably coincides with the axis of rotation of the receiving body. Of course, this refers to a state in which the film is arranged on the receiving body. The axial direction extends parallel to the axis of rotation of the film roll and preferably of the receiving body.

[0025] When the holding section is arranged in its radially inner position, the holding device is formed completely radially inside the film roll. This allows the film roll to be removed. When the holding section is arranged in its radially outer position, the holding section is formed radially outside the film roll or radially outside an inner radius of the film roll. This allows the film roll to rest on the holding section.

[0026] According to an advantageous development of the invention, the actuating element is arranged radially within the holding device. In other words, the actuating element is arranged radially inward from the holding device. If a plurality of holding devices is arranged, the holding devices circumferentially surround the actuating element. Irrespective of this, the actuating element is preferably arranged at least substantially coaxially with a rotational axis of the film roll or roll holder.

[0027] In an advantageous development of the invention, the actuating element has a contact region. The contact region can preferably be brought into contact with a contact region of the holding device in order to move the holding device from the holding position into the release position. The contact region of the actuating element is thus designed to contact, i.e., to touch, the contact region of the holding device. Through the contact, a force or movement can be transmitted from the actuating element to the holding device. The holding device can thus be moved from the holding position into the release position. Preferably, a linear movement of the actuating element is generally converted into a pivoting movement of the holding device.

[0028] Furthermore, in general, the contact area can be formed integrally with the actuating element. In particular, the actuating element is molded together with the contact area. Alternatively, the contact area can also be formed as an additional element. In this case, the actuating element and the contact area are formed in at least two pieces, with the pieces being connected to one another. The above statements regarding the contact area of ​​the actuating element can also be applied to the contact area of ​​the holding device.

[0029] According to an advantageous development, the actuating element has a further contact area. The further contact area can preferably be brought into contact with a further contact area of ​​the holding device in order to move the holding device from the release position to the holding position.

[0030] The above statements also apply to the further contact area of ​​the actuating element and the further contact area of ​​the holding device. The further contact area of ​​the actuating element is designed to come into contact with the contact area of ​​the holding device. Thus, a movement of the actuating element can also be transmitted to the holding device.

[0031] In general, the contact regions are preferably contact surfaces. Particularly preferably, the contact regions of the actuating element are at least substantially conical, especially when multiple holding devices are arranged. The cone is preferably aligned coaxially with the rotational axis of the film roll or roll holder. Particularly preferably, the contact region of the actuating element is configured as a first conical shape, and the further contact region of the actuating element is configured as a second conical shape. The two conical shapes are coaxial to one another but oriented inversely. Thus, the two conical shapes have opposite slopes.

[0032] Alternatively, it would be conceivable for the contact area of ​​the actuating element and / or the further contact area of ​​the actuating element to be designed as a slope.

[0033] In general, the contact area of ​​the holding device and / or the further contact area of ​​the holding device are preferably rounded.

[0034] According to an advantageous development of the invention, the holding device is designed to be pivotable about a pivot axis. The holding device is thus designed to be pivotable between the release position and the holding position.

[0035] Preferably, the pivot axis of the holding device is arranged orthogonally, in particular also skewed, to the rotational axis of the film roll or roll holder. Regardless of its position, the pivot axis divides the holding device into an upper region and a lower region. The contact region of the holding device is arranged in one of the upper and lower regions, and the further contact region of the holding device is arranged in the other region. Preferably, the contact region of the holding device is arranged in the upper region of the holding device.

[0036] In general, the holding section of the holding device is moved radially outwards or radially inwards when the upper area or the lower area is pushed radially outwards.

[0037] If a plurality of holding devices is arranged, each of the holding devices preferably has its own pivot axis. The pivot axes are arranged at least substantially along a circular path.

[0038] Since the holding device is pivotally mounted, a linear movement of the actuating element can be converted into a radial movement or at least a substantially radial movement of the holding device.

[0039] According to an advantageous development of the invention, the gripping mechanism has a locking device for locking the position of the holding device in the release position. The locking device is thus designed to lock or fix the holding device in the release position.

[0040] This means that when changing the film roll, the actuating element no longer needs to be held; instead, it is held in place by the locking mechanism. This allows for a quick and easy film roll change.

[0041] In an advantageous further development of the embodiment, the locking device comprises a transmission shaft and a locking body. The transmission shaft preferably extends through the roller receiving body. Furthermore, the transmission shaft preferably connects the actuating element, in particular rigidly, to the locking body.

[0042] The actuating element can be locked in a position by locking or securing the locking body. On the one hand, the actuating element moves the locking body. On the other hand, the locking body holds the actuating element in a position.

[0043] In general, as already described, the actuating element moves upward in the axial direction when actuated. Accordingly, the locking body moves upward along with the actuating element. If the locking body is finally held in an upper position, it also holds the actuating element in an upper position.

[0044] Regardless, the locking body is preferably connected directly to the transmission shaft. Furthermore, the actuating element is preferably connected directly to the transmission shaft. Furthermore, the locking body and the actuating element are arranged at two opposite ends of the transmission shaft.

[0045] According to an advantageous development of this embodiment, the locking device has a counter-body. The counter-body is designed to be movable, in particular radially, between a locking position and a release position. In the locking position, the counter-body is in contact with the locking body, in particular engaged. In the release position, the counter-body is out of contact with the locking body, in particular out of engagement. In other words, the counter-body is designed to lock or fix the locking body in its position, in particular in the upper position.

[0046] For example, the counter body forms an axial stop for the locking body, so that the locking body can no longer be moved in an axial direction, in particular downwards. Generally speaking, and for example, the locking body is at least substantially plate-shaped, with the counter body preferably being arranged below the plate-shaped locking body in the locking position.

[0047] The counter body is particularly movable radially inwards.

[0048] The locking device preferably comprises a plurality of counter-bodies. Furthermore, the counter-bodies are preferably arranged in a circumferentially distributed manner. Thus, the locking body can be held radially from multiple sides. In an advantageous further development of this embodiment, the locking device comprises a pre-tensioning element that pre-tensions the counter-body into the locking position.

[0049] This preload can ensure that the locking device is triggered as soon as the locking body is in a certain, for example upper, axial position.

[0050] In an advantageous development of the invention, the roller holder has a release device, particularly displaceable in the axial direction, for moving the locking device from the locking position to the release position. The release device is thus designed to unlock the locking device, i.e., to move it from the locking position to the release position.

[0051] As the locking device moves from the locking position to the release position, it releases the locking body, allowing the actuating element to move downward again. This moves the holding device from the release position back to the holding position.

[0052] The release device is preferably arranged coaxially to the actuating device.

[0053] Preferably, the release device is designed to move the at least one counter body into the release position, ie in particular radially outwards.

[0054] According to an advantageous development of this embodiment, the release device has a contact area. The contact area can be brought into contact with a contact area of ​​the locking device in order to move the locking device from the locked position to the release position. The contact area of ​​the release device is designed to contact or touch the contact area of ​​the locking device. Thus, a force or a movement can be transmitted from the release device to the locking device. In particular, an axial movement of the release device is transmitted into a radial movement of the locking device.

[0055] The contact area can be formed integrally with the release device. In particular, the release device can be molded integrally with the contact area. Alternatively, the contact area and the release device can be formed in multiple pieces, with these pieces then being connected to one another. The same statements also apply to the contact area of ​​the locking device.

[0056] Irrespective of this, the contact area of ​​the locking device and / or the contact area of ​​the release device are preferably a contact surface.

[0057] Particularly preferred is an inclined contact surface.

[0058] Furthermore, independently of this, the release device moves the locking device against the force of the pre-tensioning element.

[0059] According to an advantageous development, the release device is designed to be actuated by means of a film roll. In other words, the film roll can be used to trigger the release device.

[0060] For this purpose, the release device has a corresponding surface that can be contacted by a film roll. In particular, the surface can be contacted when the film roll is properly attached to the roll-receiving body. Thus, attaching a new film roll can simultaneously cause the holding device to be moved from the release position to the holding position, thus holding the new film roll to the roll holder. For this purpose, the release device is preferably designed to be displaceable in the same axial direction in which a film roll is placed onto the roll holder or the roll-receiving body.

[0061] The surface can also be a shoulder. The shoulder can be contacted by the film roll to move the release device axially, particularly upwards.

[0062] Furthermore, the problem is solved by means of a pre-stretching device for pre-stretching films with a previously described roll holder. Since the roll holder is the one already described, all individual aspects and advantages can be transferred here.

[0063] In general, the pre-stretching device is preferably part of a wrapping machine or a machine for wrapping articles, especially on pallets. The pre-stretching device is designed to stretch the film before it is wrapped around the articles. The elastic recovery force of the film then holds the articles together more tightly. In general, the roll holder and the pre-stretching device are designed for wrapping articles or packages, preferably together with pallets.

[0064] Preferably, the pre-stretching device can have at least two rollers, in particular driven independently of one another.

[0065] Short description of the drawings

[0066] The various and exemplary features described above can be combined with one another according to the invention, provided this is technically reasonable and suitable. Further features, advantages, and embodiments of the invention will become apparent from the following description of exemplary embodiments and from the figures. The figures used to explain the exemplary embodiments show:

[0067] Fig. 1 is a sectional view of a roll holder according to the invention in a holding position;

[0068] Fig. 2 is a sectional view of the roll holder shown in Fig. 1 in a release position; and

[0069] Fig. 3 is a sectional view of the roll holder shown in Fig. 1 and Fig. 2 after transfer back to the holding position

[0070] Ways to implement the invention

[0071] Fig. 1 shows a roll holder 100 according to the invention with an empty film roll 200 in a position in which the film roll 200 is held on the roll holder 100.

[0072] Fig. 2 shows the roll holder 100 shown in Fig. 1 in a release position in which the film roll 200 has been removed from the roll holder 100.

[0073] Fig. 3 shows the roll holder 100 shown in Figs. 1 and 2 with a new roll 200 being transferred back into the holding position.

[0074] The operation and structure of the roll holder 100 are explained below with reference to Figs. 1-3. The same elements in Figs. 1-3 are provided with the same reference numerals.

[0075] The roll holder shown in Fig. 1-3 serves to accommodate and hold film rolls 200. The film roll 200 contains the rolled-up film web 220, which is wound, in particular, onto a film roll body 210 (visible in Fig. 3). When the film web 220 has been completely unrolled from the film roll 200, the film roll 200 must be replaced. This means that the film roll body 210 remaining on the roll holder 100 must be removed, and a new film roll 200 must be placed onto the roll holder 100.

[0076] To accommodate the film roll 200, the roll holder 100 has a roll receiving body 110. For this purpose, the roll receiving body 110 can be inserted into a film roll 200, in particular a film roll body 210.

[0077] The roller receiving body 110 has an at least substantially cylindrical outer shape.

[0078] Furthermore, the roll holder 100 has a gripping mechanism 120. The gripping mechanism 120 extends in an axial direction through the roll receiving body 110.

[0079] At a lower region, the gripping mechanism 120 has a holding device 130 for holding the film roll 200 in the axial direction. For this purpose, the holding device 130 has a holding section 131, which, as can be seen particularly in Fig. 1 and Fig. 2, forms an axial stop for the film roll 200. This fixes the axial position of the film roll 200 such that the film roll 200 cannot slip off the roll receiving body 110.

[0080] In order to be able to remove the film roll 200 from the roll receiving body 110, the holding device 130 is designed to be transferable between a release position and a holding position. When the holding device 130 is arranged in the release position, as shown in Fig. 2, the holding section 131 is arranged in a radially inner position. However, when the holding device 130 is arranged in the holding position, as shown in Fig. 1, the holding section 131 is arranged in a radially outer position.

[0081] In Fig. 1, the holding device 130 is shown in its holding position, and in Fig. 2, the holding device 130 is shown in its release position. The gripping mechanism 120 has a release device 140 for transferring the holding device 130 from the holding position to the release position.

[0082] As can be clearly seen in particular in Fig. 1, the release device 140 has an actuating element 141. The actuating element 141 is, in particular, a manual actuating element that can be operated by hand. The actuating element 141 is designed to be displaceable in the axial direction. In particular, the actuating element 141 can be displaced axially upward from the position shown in Fig. 1 into the position shown in Fig. 2. For this purpose, the actuating element 141 must be moved against the spring force of a preloading element 142. The preloading element 142 generally urges the actuating element 141 into the lower position shown in Fig. 1.

[0083] As can be seen in Fig. 1, the actuating element 141 comes into contact with the holding device 130 when moved upward. This allows the holding device 130 to be moved from the holding position to the release position.

[0084] For this purpose, the actuating element 141 has an at least substantially conical contact area 143. The contact area 143 comes into contact with a contact area 132 of the holding device 130 and thus transmits a movement of the actuating element 141 to the holding device 130.

[0085] The holding device 130 is pivotable about a pivot axis S. An upper region 134 is formed above the pivot axis S and a lower region 135 is formed below the pivot axis S. If the upper region 134 is moved radially outward by contact with the actuating element 141, the lower region 135 moves radially inward accordingly. As a result, the holding section 131, which is arranged at the lower region 135, moves radially inward upon actuation of the actuating element 141. This is particularly clearly evident when comparing Fig. 1 and Fig. 2.

[0086] Furthermore, the gripping mechanism 120 has a locking device 150 for locking the position of the holding device 130 in the release position shown in Fig. 2. The locking device 150 has a transmission shaft 151 that extends through the roller receiving body 110. The actuating element 141 is located at a lower end of the transmission shaft 151. A locking body 152 is located at an upper end of the transmission shaft 151. The transmission shaft 151 rigidly connects the actuating element 141 to the locking body 152. Thus, by locking the locking body 152, the actuating element 141 can also be locked, i.e., held in its position.

[0087] To secure the locking body 152, the locking device 150 has a counter-body 153. As shown in Fig. 2, the counter-body 153 is designed, in a locking position, to come into contact with the locking body 152 such that the locking body 152 is axially fixed. For this purpose, the locking device 150 has a preloading element 154 that preloads the counter-body 153 into the locking position.

[0088] If the locking body 152 moves far enough upwards from Fig. 1 to Fig. 2, the counter body 153 is moved radially inwards due to the preload of the preload elements 154 and can thus form an axial stop for the locking body 152.

[0089] In the position shown in Fig. 2, the film roll 200 could thus be easily removed from the roll holder 100, and the holding device 130 remains in its release position for attaching a new film roll 200. In order to re-fix this new film roll 200 to the roll holder 100, the roll holder 100 has a release device 160. The release device 160 is designed to move the locking device 150 from the locking position shown in Fig. 2 into the release position shown, for example, in Fig. 3.

[0090] For this purpose, the release device 160 is movable axially, in particular upwards. The release device 160 has a shoulder 163. When a new film roll is inserted, it comes into contact with the shoulder 163, as shown in Fig. 3. This allows the shoulder 163 and thus the release device 160 to be moved upwards. At an end opposite the shoulder 163, the release device 160 has a contact area 161. The contact area 161 can be brought into contact with a contact area 155 of the locking device. This can be seen in particular in Fig. 3, in which the contact area 161 of the release device 160 is in contact with the contact area 155 of the locking device 150. As a result of this contact, the locking device 150 can be moved from its locked position shown in Fig. 2 to its release position shown in Fig. 3. In the release position, the counter body 153 is out of contact with the locking body 152.Due to the pre-tensioning element 142, the locking body 152 together with the actuating element 141 is then moved downwards.

[0091] As can be seen in Fig. 3, during this movement of the actuating element 141, a further contact area 144 of the actuating element 141 comes into contact with a further contact area 133 of the holding device 130. The further contact area 133 is located in the lower area 135 of the holding device 130, so that the holding section 131 moves back outward, i.e., into its holding position.

[0092] Then, the new film roll 200 can be lowered downwards until it axially abuts the holding section 131. Reference numeral

[0093] 100 roll holders

[0094] 110 roll holder body

[0095] 120 gripping mechanism

[0096] 130 Holding device

[0097] 131 stopping section

[0098] 132 Contact area (of the holding section)

[0099] 133 additional contact area (of the holding section)

[0100] 134 upper area

[0101] 135 lower area

[0102] 140 Release device

[0103] 141 Actuating element

[0104] 143 Contact area (of the actuating element)

[0105] 144 additional contact area (of the actuating element)

[0106] 150 locking device

[0107] 151 Transfer shaft

[0108] 152 locking bodies

[0109] 153 Counterbodies

[0110] 154 Prestressing element

[0111] 155 Contact area (of the counter body)

[0112] 160 release device

[0113] 161 Contact area (of the release device)

[0114] 163 Shoulder

[0115] 200 film rolls

[0116] 210 film roll bodies

[0117] 220 film strips

[0118] S swivel axis

Claims

Patent claims 1. Roll holder (100) for receiving and holding film rolls (200) from rolled-up film webs (220), the roll holder (100) comprising: a roll receiving body (110) which can be inserted into a film roll (200);and a gripping mechanism (120) extending in an axial direction through the roll receiving body (110), wherein the gripping mechanism (120) has a holding device (130) for holding the film roll (200) in the axial direction, wherein the holding device (130) is designed to be transferable between a release position and a holding position, wherein the gripping mechanism (120) has a release device (140) for transferring the holding device (130) into the release position, and wherein the release device (140) has an actuating element (141) which is designed to be displaceable in the axial direction and can be brought into contact with the holding device (130) in order to transfer the holding device (130) from the holding position to the release position.; 2. Roll holder (100) according to claim 1, wherein the holding device (130) has a holding section (131) which forms an axial stop for the film roll (200) in the holding position of the holding device (130).

3. Roll holder (100) according to claim 2, wherein the holding portion (131) is arranged in a radially inner position when the holding device (130) is arranged in the release position, and wherein the holding section (131 ) is arranged in a radially outer position when the holding device (130) is arranged in the holding position.

4. Roller holder (100) according to one of the preceding claims, wherein the actuating element (141) is arranged radially inside the holding device (130).

5. Roll holder (100) according to one of the preceding claims, wherein the actuating element (141) has a contact region (143) which can be brought into contact with a contact region (132) of the holding device (130) in order to move the holding device (130) from the holding position into the release position.

6. Roll holder (100) according to one of the preceding claims, wherein the actuating element (141) has a further contact area (144) which can be brought into contact with a further contact area (133) of the holding device (130) in order to move the holding device (130) from the release position into the holding position.

7. Roll holder (100) according to one of the preceding claims, wherein the holding device (130) is designed to be pivotable about a pivot axis (S).

8. Roll holder (100) according to one of the preceding claims, wherein the gripping mechanism (120) has a locking device (150) for locking the position of the holding device (130) in the release position.

9. Roll holder (100) according to claim 8, wherein the locking device (150) comprises a transmission shaft (151) and a locking body (152), wherein the transmission shaft (151) extends through the roll receiving body (110) and connects the actuating element (141) to the locking body (152).

10. Roll holder (100) according to claim 9, wherein the locking device (150) has a counter body (153) which is designed to be movable between a locking position and a release position, wherein the counter body (153) is in contact with the locking body (152) in the locking position, and wherein the counter body (153) is out of contact with the locking body (152) in the release position.

11. Roll holder (100) according to claim 10, wherein the locking device (150) has a biasing element (154) which biases the counter body (153) into the locking position.

12. Roll holder (100) according to one of claims 8 to 11, wherein the roll holder (100) has a release device (160) for moving the locking device (150) from the locking position to the release position.

13. Roll holder (100) according to claim 12, wherein the release device (160) has a contact area (161) which can be brought into contact with a contact area (155) of the locking device (150) in order to move the locking device (150) from the locking position to the release position.

14. A roll holder according to claim 12 or 13, wherein the release device (160) is operable by means of a film roll (200).

15. A pre-stretching device for pre-stretching film with a roll holder (100) according to one of the preceding claims.

Images