Abstract:
Apparatus for controlling rolling motion of a cylindrical object includes a fixed plane formed with guides that are spaced apart along a direction of rolling motion of the cylindrical object and provide a path from an upper surface of the plane to the underside of the plane. An elongate pressure element has a medial segment located on the upper surface of the fixed plane and has first and second ends that are guided to the underside of the plane via the first and second guides respectively. A control device has first and second connections and is operable selectively for providing a pressure medium under pressure discharging the pressure medium to a lower pressure. One of the first and second connections of the control device is connected to the first end of the elongate pressure element and the other of the first and second connections is connected to the second end of the elongate pressure element, for selectively filling the pressure element with a pressure medium through at least one of the first and second ends and for draining the pressure medium from the pressure element through at least one of the first and second ends.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims priority under 35 USC 119 of Finnish Patent Application No. 20050337 filed Mar. 31, 2005.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of Technology  
         [0003]     This invention relates to controlling the rolling of a cylindrical object such as a reel of paper.  
         [0004]     2. Prior Art  
         [0005]     Lots of cylindrical objects are moved at paper mills, print shops and metal rolling mills, for example. Different types of conveyors and cranes have been developed for the movement of cylindrical objects. Rolling is a known method.  
         [0006]     When a cylindrical object is being rolled, its movement is controlled by different types of pushers and receivers. It is also known that a cylindrical object is rolled on a slightly inclined floor plane. However, it is difficult to roll large and heavy cylindrical objects, because rolling a heavy mass requires force. The pushers and receivers must be dimensioned to be strong, which makes them heavy and relatively large.  
         [0007]     Reels of paper in particular are sensitive to damage caused by rolling. It is difficult to control the speed of the reel during rolling, and the speed may become higher than intended. This will easily make the reel bounce against the stopper and can cause mechanical damage on the surface of the paper reel. It is thus clear that stopping a heavy cylindrical object will also require a lot of force and a strong receiver.  
         [0008]     Patent Publication FI 96759 describes a known stopper for a cylindrical object that can also be used as a retarder. The solution according to the publication comprises a fixed plane and a moving plane. One end of the moving plane is mounted to the base structure by hinges that allow the moving plane to move in relation to the axis formed by the hinge, creating an inclined plane. There is a compressible hose filled with a flowing pressure medium on top of the moving plane. There is another compressible hose between the moving plane and the fixed plane. The pressure medium can flow from the first hose into this second hose when a paper reel or other cylindrical object rolls on top of the stopper. The hose located on top of the moving plane will be compressed, and the pressure medium contained in the first hose tries to flow into the second hose. When the second hose becomes filled with the pressure medium, the second hose expands and the moving plane tilts up. The rolling object is thus stopped by the combined effect of the hose filled with pressure medium and the inclination of the moving plane that reduces the rolling speed of the reel. If the solution is used as a stopper, the reel will stop on top of the inclined plane. If the solution is used as a retarder, the reel is allowed to roll over the inclined plane without stopping. This solution is relatively heavy, and controlling the stopping of the reel on the inclined plane requires great accuracy. Furthermore, as the reel rolls over the inclined plane onto the horizontal plane, mechanical damage may arise on the surface of the reel.  
       SUMMARY OF THE INVENTION  
       [0009]     The objective of the invention is to eliminate problems of prior art solutions.  
         [0010]     An arrangement according to the invention comprises at least one pressure element, such as a compressible hose or mat, to be filled with a pressure medium. The pressure element has a first end and a second end.  
         [0011]     The arrangement also comprises a fixed plane or table with conduits or guides for conducting the first and second ends of the pressure element located on top of the fixed plane to the underside of the plane. The conduit for the first end is located at a different part of the planned line of rolling the cylindrical object compared to the conduit for the second end.  
         [0012]     Furthermore, the arrangement includes a control means for filling the pressure element with a pressure medium and draining it of the pressure medium, as well as a connection means for each end of the pressure element. The connection means can be used to connect the pressure element to the control means.  
         [0013]     The control means can be used to fill the pressure element in a controlled manner through either or both ends of the pressure element, as well as drain it in a controlled manner through either or both ends. Thus the state of motion of the cylindrical object on top of the plane and the pressure element can be changed from a rolling state to a stopped state and vice versa in a controlled manner in the direction of the desired line of rolling.  
         [0014]     The arrangement according to the invention provides for very good control of the rolling movement of a cylindrical object. Furthermore, the structure of the arrangement according to the invention is light compared to prior art solutions, as the state of motion of the cylindrical object can be controlled using force imposed on the object by a pressure element filled with a pressure medium, eliminating the need for other structures (such as pushers or stoppers).  
         [0015]     Furthermore, the solution according to the invention is applicable for use on a horizontal as well as an inclined plane. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]     In the following, the invention is described in more detail by reference to the enclosed drawings, where  
         [0017]      FIG. 1  illustrates an example of an arrangement according to the invention in which the plane is inclined,  
         [0018]      FIG. 2  illustrates an example of an arrangement according to the invention in which the plane is horizontal,  
         [0019]      FIG. 3  illustrates an example of an embodiment of control means according to the invention,  
         [0020]      FIG. 4  illustrates another example of an embodiment of control means according to the invention,  
         [0021]      FIG. 5  illustrates a third example of an embodiment of control means according to the invention,  
         [0022]      FIG. 6  illustrates a fourth example of an embodiment of control means according to the invention,  
         [0023]      FIG. 7  illustrates a fifth example of an embodiment of control means according to the invention,  
         [0024]      FIG. 8  illustrates a sixth example of an embodiment of control means according to the invention,  
         [0025]      FIG. 9  illustrates an example with three arrangements according to the invention in sequence to create one large arrangement according to the invention,  
         [0026]      FIG. 10  illustrates another example with three arrangements according to the invention in sequence to create one large arrangement according to the invention, and  
         [0027]      FIG. 11  illustrates a third example with three arrangements according to the invention in sequence to create one large arrangement according to the invention. 
     
    
     DETAILED DESCRIPTION  
       [0028]      FIG. 1  illustrates an example of an arrangement according to the invention. In the arrangement illustrated in the example, the fixed plane  2  is inclined. The intention is that a cylindrical object  1 , such as a reel of paper, is placed on the plane so that its direction of rolling is downwards along the inclined plane. The arrow in the figure illustrates the direction of rolling. There is a pressure element  3  on top of the plane, and it can be filled with a pressure medium. The pressure element may be a compressible hose or mat, for example. Several pressure elements may be placed on the plane side by side in the axial direction of the cylindrical object as will be discussed in detail below. Parallel pressure elements may be placed in a staggered arrangement. Pressure elements may also be placed sequentially on the plane.  
         [0029]     Conduits or guides  4  are arranged on the plane  2  for conducting or passing the ends of the pressure element  3  below the top surface of the plane. The conduits for the ends of an individual pressure element are located at different positions along the planned line of rolling of the cylindrical object. The arrow in the figure also illustrates the direction of the line of rolling downwards on the inclined plane. Thus, when rolling, the cylindrical object can only press a single conduit of a pressure element end at a time.  
         [0030]     The ends of the pressure element  3  that have been conducted below the top surface of the plane  2  are connected to a control means  6  using which the pressure element  3  can be filled with pressure medium and drained of pressure medium. The connection between the control means and the pressure element is carried out by using connectors  5  at both ends of the pressure element.  
         [0031]     The control means  6  can be used to fill the pressure element  3  in a controlled manner through either or both ends of the pressure element, as well as drain it in a controlled manner through either or both ends. Filling and draining the pressure element using the control means makes it possible to change the state of motion of a cylindrical object on top of the plane  2  and the pressure element  3  from a rolling state to a stopped state and vice versa in a controlled manner in the direction of the desired line of rolling.  
         [0032]     When the cylindrical object  1  rolls down the plane  2  in the example of  FIG. 1 , it compresses the pressure element  3 . If the control means  6  is set to limit or prevent discharge of the pressure medium from the pressure element  3 , the pressure of the pressure medium within the pressure element increases. This pressure is controlled by the control means  6  so that the rolling speed of the cylindrical object can be reduced or the object can be made to stop on top of the pressure element. The cylinder drawn with a dashed line illustrates the fact that the arrangement is suitable for different sizes of cylindrical objects  1 .  
         [0033]      FIG. 2  illustrates an example of an arrangement according to the invention in which the plane  22  is horizontal. Furthermore,  FIG. 2  also shows a supply connector  20  for connecting the control means  6  to an external source  21  of pressure medium. The supply connector is used to supply the pressure medium to the control means  6  from which it can be further conducted to the pressure element  3 .  
         [0034]     The pressure medium may be compressed air or other compressed gas suitable for the purpose. The pressure medium may also be a suitable liquid such as water. In the embodiment of  FIG. 1 , the circulation of the pressure medium is closed; thus, when the pressure element is drained, the pressure medium flowing out of the pressure element is recirculated within the control means for feeding it back to the pressure element. No external source of pressure medium is required. In the embodiment of  FIG. 2 , the circulation of the pressure medium is open; when the pressure element is drained, the pressure medium flowing out of the pressure element is not recirculated but is conducted out of the control means. For example, compressed air may be released to ambient atmosphere. Water serving as a pressure medium may be conducted to the sewer.  
         [0035]     The situation in  FIG. 2  illustrates the versatile possibilities of the arrangement according to the invention to move a cylindrical object along its line of rolling. The bidirectional arrow illustrates this. In the situation in  FIG. 2 , the cylindrical object has rolled from the right to the left on top of the pressure element  3  and compressed the pressure element. The pressure in the left-hand section of the pressure element has increased, and the cylindrical object can be stopped by controlling the pressure. The stopped cylindrical object can be moved back to the right by using the control means  6  to increase the pressure of the pressure medium in the left-hand section of the pressure element  3 . Alternatively, the movement of the stopped object can also be continued to the left by increasing the pressure of the pressure medium in the right-hand section of the pressure element  3 .  
         [0036]     In the situation in  FIG. 2 , the cylindrical object can be moved back and forth on the horizontal plane  22  but this is also possible on an inclined plane. In other words, the arrangement according to the invention also allows a cylindrical object to be moved upwards along an inclined plane.  
         [0037]     The plane  2 ,  22  in an arrangement according to the invention is horizontal or is inclined in relation to the horizontal. The plane may be a sheet or mat placed on a base. The sheet may be a plywood board, for example. It is reasonable to use a mat if the cylindrical object is particularly sensitive to damage caused by rolling. The plane may also be a combination of a plywood board and a mat. The base for the plane may be a concrete slab or a separate support structure.  
         [0038]     The plane has conduits  4  for the ends of the pressure elements. A conduit  4  may be an opening in the plane or a recess at an edge area of the plane. The edge of the plane may also be shaped to be more suitable for the end of the pressure element. In particular, the plane may be shaped at the opening or guide so that edges over which the pressure element passes are rounded, to avoid damage to the pressure element when the cylindrical object rolls over the pressure element by virtue of the pressure element being forced against a sharp edge. If a separate support structure is used as the base for the plane, space will remain or can easily be arranged below the plane  2 ,  22  for the placement of the pressure element ends, the connectors  5  and the control means  6 . However, the control means may also be placed close to the plane, such as to the side of the area formed by the plane.  
         [0039]     The surface of the base, such as concrete, can also serve as the plane  2 ,  22 . In this case, the conduit  4  is a recess or opening in the base.  
         [0040]     The control means  6  according to the invention may be implemented in several ways depending on the application. For example, if an application only requires a retarder for a cylindrical object, the control means does not need to be able to move the cylindrical object back and forth. Different types of control means may also be created for the same application. FIGS.  3  to  8  illustrate various embodiments of the control means  6 .  
         [0041]      FIG. 3  illustrates an example of an embodiment of the control means  6  according to the invention. In the embodiment, the control means  31  has a supply connection  20  to an external source of pressure medium and comprises a pressure relief valve  32  connected to the supply connection  20  to limit the pressure of the pressure medium, a pressure gauge  37  to indicate the pressure limited by the pressure relief valve, and a first choke valve  33  connected to the pressure relief valve on the side of pressure to be limited. Furthermore, the control means comprises a second choke valve  36  to limit the flow of the pressure medium from the pressure element to outside the control means  6 , and a pressure control valve module  34  that is connected to the connectors  5  at the ends of the pressure element  3  and is connected to the first choke valve  33  and the second choke valve  36 .  
         [0042]     The pressure relief valve  32  can preferably be set to the desired value, while the pressure gauge  37  provides a readout of the pressure limited by the valve  32  and is thus used for setting the pressure. The pressure may be set to 3 bar, for example. The choke valves  33 ,  36  are used to affect the flow rates of the pressure medium.  
         [0043]     The pressure control valve module  34  controls the filling of the pressure element  3  with the pressure medium and draining of the pressure medium from the pressure element  3 . The module comprises two 3/2 pressure control valves  35 , each of which has a port connected to the first choke valve  33  and also has a port connected to the second choke valve  36 . Furthermore, the third ports of the two valves are connected respectively to the connectors  5  of the pressure element  3 . The pressure control valves may be controlled so that when one of the valves  35  is set to allow the flow of the pressure medium to one end of the pressure element, the other valve will allow the flow of the pressure medium from the other end of the pressure element through the second choke valve  36  to outside the control means. The valves may be controlled using a mechanical lever, electric control or other control mechanism suitable for the purpose.  
         [0044]     The control means  31  of  FIG. 3  allows the rolling of a cylindrical object to be retarded or stopped, and also allows the cylindrical object to be set in motion in a desired direction. In other words, a stationary cylinder located on top of the pressure element  3  can be set to move in the desired direction.  
         [0045]      FIG. 4  illustrates another example of an embodiment  41  of the control means according to the invention; this is actually a variation of the embodiment in  FIG. 3 . In the embodiment in  FIG. 4 , the control means  41  also comprises a non-return valve  48  connected to the supply connection  20  to prevent return flow of the pressure medium from the control means  41  to the external source of pressure medium, a pressure medium tank  49  connected to the non-return valve  48  at the supply connection  20 , as well as a pressure relief valve  32 . A pressure gauge  37  is installed in connection with the pressure relief valve. The non-return valve  48  prevents any over-pressurized pressure medium from flowing from the control means back to the external source of pressure medium  21 . The tank  49  functions as a reserve for the pressure medium.  
         [0046]     The embodiment in  FIG. 4  also comprises non-return valves  42  connected to the connectors  5  respectively. These non-return valves  42  are connected to the pressure control valve module  34  so that they allow the pressure medium to flow to the pressure element  3  and normally prevent reverse flow of the pressure medium from the pressure element. However, the valves  42  may each be controlled so that they allow reverse flow of the pressure medium from the pressure element  3 . In this example, the non-return valves are controlled by the pressure of the pressure medium. The pressure required for control is supplied to an individual non-return valve at one end of the pressure element from the supply to the opposite end of the pressure element. Thus the supply  43  that supplies pressure medium to the non-return valve at the first end of the pressure element also supplies control pressure to the non-return valve at the second end of the pressure element. Correspondingly, the supply  44  that supplies pressure medium to the second end of the pressure element also supplies control pressure to the non-return valve at the first end of the pressure element. As illustrated in  FIG. 4 , the supplies  43 ,  44  are in practice connections from the directional valves of the control module  34  to the connectors  5 . The non-return valves  42 ,  48  in the embodiment are preferably spring-loaded.  
         [0047]     In the embodiment in  FIG. 4 , one-way restrictor valves  45 ,  46  are used in place of the choke valves in  FIG. 3 . However, it is possible to use simple choke valves instead of the one-way restrictor valves in  FIG. 4 . A one-way restrictor valve provides free flow of pressure medium in one direction and restricted flow in the opposite direction. It is preferable to fit the one-way restrictor valve  46  on the exhaust route with a muffler  47  if the pressure medium is a gas such as air.  
         [0048]     The operation of the embodiment in  FIG. 4  is similar to the embodiment in  FIG. 3 . When the pressure element is being filled from either end, the non-return valve at the other end of the pressure element is instructed to open so that it allows the pressure medium to flow out of the pressure element.  
         [0049]     The directional valves used in the pressure control valve module  34  of the examples may be of a type other than 3/2. For example, a directional valve of type 5/2 may be used. Use of 5/2 valves also provides additional features. For example, 5/2 valves allow the pressure element to be filled and drained simultaneously from both ends of the pressure element. These two examples illustrate that the control means can be implemented in many different ways. The implementation can include a pressure medium tank, for example, if it is considered necessary for practical reasons.  
         [0050]      FIG. 5  illustrates a third example of an embodiment of control means according to the invention. This embodiment  51  is intended to function as a retarder and stopper of the rolling movement of a cylindrical object.  
         [0051]     The control means  51  in  FIG. 5  has a supply connection  20  to an external source of pressure medium and comprises a pressure relief valve  32  connected to the supply connection  20  to limit the pressure of the pressure medium, a pressure gauge  37  to indicate the pressure limited by the pressure relief valve, and a one-way restrictor valve  52  connected to the pressure relief valve  32  on the side of limited pressure so that it allows free flow of the pressure medium towards the pressure element  3 . The one-way restrictor valve  52  may also be functionally connected to the connectors  5  at both ends of the pressure element  3 . The connector  5  at the first end of the pressure element may be connected directly to the one-way restrictor valve. The connector  5  at the second end of the pressure element may be connected through a choke valve  53 . The choke valve  53  retards the flow of the pressure medium at the second end of the pressure element.  
         [0052]     The pressure element is filled primarily through the first end of the pressure element as the choke valve  53  retards flow to the second end of the pressure element. The pressure element is also drained primarily through the first end of the pressure element because the choke valve  53  also restricts the flow of pressure medium flowing from the second end of the pressure element. The exhaust flow goes through the one-way restrictor valve  52  to the pressure relief valve  32  from which it is released to outside the control means  51 .  
         [0053]     In this embodiment  51 , the intention is that the cylindrical object will roll to the top of the pressure element from the direction of the second end of the pressure element, i.e., the end at which flow is restricted by the one-way restrictor valve  52  and the choke valve  53 . The resistance of the choke valve  53  is lower than that of the one-way restrictor valve  52 . The pressure relief valve  32  restricts the pressure to the range of 1 to 2.5 bar, for example.  
         [0054]     Components considered necessary can be added to the embodiment in  FIG. 5 , such as a one-way restrictor valve and a pressure medium tank between the supply connection  20  and the pressure relief valve  32 . A non-return valve may be connected in series with the choke valve  53  between the second end of the pressure element and the one-way restrictor valve  52 . The embodiment  51  is applicable for use on a horizontal or inclined plane.  
         [0055]      FIG. 6  illustrates a fourth example of an embodiment  61  of the control means according to the invention. The control means  61  is used with three pressure elements (not shown), although the connectors  5  for only one pressure element are shown. Similar to  FIG. 5 , this embodiment functions as a retarder and stopper of a cylindrical object. The control means  61  has a supply connection  20  to an external source of pressure medium and comprises a non-return valve  48  connected to the supply connection  20 , as well as non-return valves  67 ,  54  specific to the connectors  5 . The non-return valves are connected to the connectors  5  to allow the pressure medium to flow out of the pressure element  3  when the pressure of the pressure medium within the pressure element is sufficiently high.  
         [0056]     At least one of the non-return valves  67 ,  54  specific to the connectors  5  of each pressure element is controllable so that it allows the pressure medium to flow into the pressure element. In practice, this means that the non-return valves associated with the first end of the respective pressure elements are controllable.  FIG. 6  illustrates three controllable non-return valves for the first ends of the three pressure elements respectively. Three non-return valves are provided for the second ends of the pressure elements although only one of these non-return valves is shown in  FIG. 6 .  
         [0057]     The embodiment in  FIG. 6  also comprises a directional valve  62  to control the flow of the pressure medium into and out of the pressure element(s). The first port of the directional valve is connected to the non-return valve  48  at the supply connection, while the second port is functionally connected to the non-return valves  67 ,  54  specific to the connectors  5 . The third port of the directional valve is connected to a space outside the control means, preferably through a muffler  63  when the pressure medium is air.  
         [0058]     The second port of the directional valve  62  is connected through route  64  to the pressure relief valve  32 , which is further connected to the one-way restrictor valve  52 . The one-way restrictor valve allows free flow of the pressure medium towards the pressure element(s). The pressure relief valve limits the pressure of the pressure medium in section  66  of the control means that is connected to the non-return valve  67  at the first end of the pressure element  3 . The pressure relief valve is also associated with a pressure gauge  37  for indicating the pressure limited by the pressure relief valve.  
         [0059]     The embodiment  61  also comprises a pressure switch  68  connected to the connection  66  between the one-way restrictor valve  52  and the non-return valve  67  for the purpose of detecting the pressure of the pressure medium and providing a control signal to the directional valve  62 . The pressure switch  68  in  FIG. 6  provides an electrical control signal to the winding of the directional valve  62 . The directional valve may also be controlled hydraulically or pneumatically, for example, depending on the pressure medium used. For the sake of safety, another pressure gauge  69  may be connected to the connection  66 .  
         [0060]     The operation of the embodiment  61  in  FIG. 6  mainly corresponds to the operation of the embodiment  51  in  FIG. 5 . The rolling direction of the cylindrical object is from the second end of the pressure element towards the first end. The pressure element can be filled through the controlled non-return valve  67  at the first end. The directional valve  62  in  FIG. 6  is in the non-driven position, allowing the pressure medium to flow to the side of the second port of the directional valve and further to the first end of the pressure element through the pressure relief valve  32 . The second port of the directional valve  62  also is connected to a control connection  65  for the controlled non-return valve  67  at the first end of the pressure element and to the non-return valve  54  at the second end of the pressure element. When the cylindrical object compresses the pressure element, the pressure of the pressure medium increases in the first end of the pressure element and the non-return valve  67  allows the pressure medium to flow towards the pressure relief valve. The pressure increases within the connection  66  between the non-return valve  67  and the pressure relief valve  32 , activating the pressure switch  68 , which provides a signal for controlling the directional valve  62 . The controlled directional valve  62  changes position, and the directional valve  62  conducts the pressure medium from the second port to the third port and thence outside the control means. Thus the over-pressurized pressure medium in the first end of the pressure element flows out of the control means through the pressure relief valve  32 . Any over-pressure in the second end of the pressure element and the control pressure of the controlled non-return valves  67  are released through the directional valve  62 .  
         [0061]     It should be noted that the directional valve  62  in the embodiment in  FIG. 6  is a 3/2 valve but could alternatively be a 5/2 valve.  
         [0062]      FIG. 7  illustrates a fifth example of an embodiment  71  of the control means according to the invention, similar to the embodiment in  FIG. 6 . The control properties of the arrangement can be affected by using two directional valves in this embodiment instead of one.  
         [0063]     Similar to the embodiment in  FIG. 6 , the control means  71  has a supply connection  20  to an external source of pressure medium and comprises a non-return valve  48  connected to the supply connection  20 , non-return valves  67 ,  54  specific to the connectors  5 , a pressure relief valve  32 , a pressure gauge  37  to indicate the pressure limited by the pressure relief valve, a one-way restrictor valve  52  connected to the pressure relief valve  32  on the side of pressure to be limited, a directional valve  72 , a pressure switch  68  and an optional second pressure gauge  69 .  
         [0064]     The embodiment  71  also comprises an optional pressure medium tank  49  connected to the non-return valve  48  of the supply connection, a second directional valve  74 , and a second one-way restrictor valve  46  which may also be replaced by an ordinary choke valve.  
         [0065]     The pressure medium tank  49  (or, alternatively, the non-return valve  48  of the supply connection) is connected to both the pressure relief valve  32  and the directional valve  72 . In this case, the first directional valve is a 5/2 valve. Its first port is connected to the pressure tank  49 , while the second port is connected to the non-return valve  54  at the second end of the pressure element and the control of the non-return valve  67  at the first end of the pressure element. Thus the first-end control connection  65  exists for the control of the non-return valve  67 . The third and fifth ports are connected outside the control means. When using gas, the third and fifth ports are preferably provided with mufflers  63 . The fourth port of the first directional valve  72  has a control connection  73  to the control part of the second directional valve  74 .  
         [0066]     The first port of the second directional valve  74  is connected to the first one-way restrictor valve  52  which allows free flow towards the first end of the pressure element. The second port of the second directional valve has a connection  75  to the controlled non-return valve  67  at the first end of the pressure element, and the third port is connected to the second one-way restrictor valve  46 , which is connected outside the control means. If the pressure medium is a gas, such as air, it is preferable to use a muffler  47  in connection with the second one-way restrictor valve  46 .  
         [0067]     When the cylindrical object increases the pressure of the pressure medium at the first end of the pressure element, the pressure also increases within the connection  75  between the non-return valve  67  at the first end and the second directional valve  74 , making the pressure switch  68  provide a control signal to the first directional valve  72 . The first directional valve  72  changes position so that the pressure medium is allowed to flow through the fourth port to the control part of the second directional valve  74 , changing the position of the second directional valve. In this case the connection  75  between the non-return valve  67  at the first end of the pressure element and the second directional valve  74  is connected to the third port of the second directional valve. The pressure medium is allowed to flow out of the control means through the third port and the second one-way restrictor valve  46 . At the same time, the second port of the first directional valve is connected to outside the control means through the third port, allowing the pressure medium to flow out of the control connection  65 .  
         [0068]      FIG. 8  illustrates a sixth example of an embodiment  81  of the control means according to the invention. This embodiment is particularly well suited for inclined surfaces on which the intention is to retard and stop a cylindrical object, and potentially move it back up on the inclined plane.  
         [0069]     The embodiment in  FIG. 8  has a supply connection  20  to an external source of pressure medium and comprises a non-return valve  48  connected to the supply connection  20 , as well as non-return valves  67 ,  54  that are specific to the connectors  5  and are connected to each connector  5  to allow the pressure medium to flow out of the pressure element  3  when the pressure of the pressure medium within the pressure element is sufficiently high. At least one of the non-return valves at the ends of the pressure element is controllable so that it allows the pressure medium to flow into the pressure element  3 .  
         [0070]     The embodiment also comprises a pressure relief valve  32  connected to a pressure medium tank  49 , a pressure gauge  37  to indicate the pressure limited by the pressure relief valve, and a one-way restrictor valve  52  connected to the pressure relief valve  32  on the side of limited pressure so that it allows free flow of the pressure medium towards the pressure element.  
         [0071]     The embodiment also comprises a first quick exhaust valve  89  with its non-return valve input connected to the one-way restrictor valve  52  and the intermediate input connected to the controllable non-return valve  67  at the first end of the pressure element. The connection  88  between the non-return valve  67  and the quick exhaust valve  89  is fitted with a pressure switch  68  to detect the pressure of the pressure medium and provide a control signal. An additional pressure gauge  69  can also be connected to this connection  88 .  
         [0072]     The embodiment in  FIG. 8  also comprises a first directional valve  72  with its first port connected to the connection between the pressure medium tank  49  and the pressure relief valve  32 , the second port connected to the non-return valve  54  specific to the connection means at the second end of the pressure element, and the third and fifth ports connected to a volume outside the control means. The fourth port of the first directional valve  72  is connected to the first port of the second directional valve  82 . The second and third ports of the second directional valve are closed. The fifth port is connected to a space outside the control means. The auxiliary control of the second directional valve is connected  83  to the pressure in the pressure medium tank  49 .  
         [0073]     The embodiment also includes a second pressure relief valve  811  with the limited-pressure side connected  810  to the output of the first quick exhaust valve  89  and the other side connected to the fourth port of the second directional valve  82 . The second pressure relief valve  811  is also associated with a second pressure gauge  812  for indicating the pressure limited by the second pressure relief valve.  
         [0074]     The embodiment also includes a second quick exhaust valve  86  with its output connected to the connection  813  between the second pressure relief valve  811  and the second directional valve  82 . The non-return valve input of the second quick exhaust valve  86  is connected  85  to the connection between the first directional valve  72  and the non-return valve  54  at the second end of the pressure element. The intermediate input of the second quick exhaust valve  86  is connected  87  to the control of the controlled non-return valve  67 .  
         [0075]     When the cylindrical object causes an increase of pressure in the first end of the pressure element, this is detected by the pressure switch  68 . Because the limiting pressure of the first pressure relief valve  32  (for example, 1 to 2.5 bar) is set to be lower than the limiting pressure of the second pressure relief valve  811  (for example, 3 bar), the pressure medium is allowed to flow out of the control means through the first pressure relief valve.  
         [0076]     The pressure switch  68  simultaneously issues a control signal to the first directional valve  72  that cuts the supply of pressure medium to the non-return valves  54 ,  67  at the ends of the pressure element and simultaneously allows the control connection  87 ,  85  of the first-end non-return valve  67  to be drained through the third port of the first directional valve  72  to outside the control means. This allows the rolling movement of the cylindrical object to be retarded and stopped.  
         [0077]     If the stopped cylindrical object needs to be moved back up on the inclined plane, a control signal is issued to the second directional valve  82  to change its position. The pressure medium flows through the still driven first directional valve  72  and the fourth port of the second directional valve to the second quick exhaust valve  86  and the second pressure relief valve  811 . The pressure medium flowing to the second quick exhaust valve flows through the control connection  87  to the controlled non-return valve  67  at the first end of the pressure element, opening it for the purpose of filling the pressure element. The actual pressure medium filling the pressure element flows through the second directional valve  811 , the first quick exhaust valve  89  and the controlled non-return valve  67  to the first end of the pressure element, making the filling pressure element to move the cylindrical object up on the inclined plane.  
         [0078]     The auxiliary control  83  is required to control the second directional valve  82  when the first directional valve  72  is not driven. However, for such a situation, the second directional valve can also be fitted with a control in which auxiliary control is not required.  
         [0079]     FIGS.  3  to  8  illustrate embodiments in which the pressure medium is a gas or liquid suitable for the purpose. The embodiments also illustrate that the control means  6  can be implemented in many different ways.  
         [0080]      FIG. 9  illustrates an example with several arrangements according to the invention in sequence to create a larger area  91  for moving a cylindrical object. This example has three sequential arrangements  92 ,  93 ,  94 , one of them  94  being different from the two others  92 ,  93 . Each of the arrangements has hoses  95 ,  96 ,  97 ,  98  arranged in parallel, and these can be filled with and drained of a pressure medium. The ends of the hoses are conducted through conduits  99  below the top surface of the planes where they are connected to the control means.  
         [0081]     The dual dotted lines  912 ,  911 ,  910 ,  913  illustrate cylindrical objects on top of the plane. As can be seen, the same arrangement can be suitable for different cylindrical objects.  
         [0082]     In the two similar arrangements  92 ,  93 , the hoses are of equal length but the middle hoses  96  are narrower than the other hoses  99  in the arrangement. In the arrangement  94 , the middle hoses  97  are also shorter than the other hoses  98 . It can thus be seen that the hoses functioning as the pressure elements can be of different gauges and lengths depending of the arrangement.  
         [0083]      FIG. 10  illustrates another example with three arrangements  102 ,  103 ,  104  according to the invention in sequence. In each arrangement, the pressure elements or the hoses  105 ,  106 ,  107 ,  108  are arranged in parallel, but some of them  105  are located staggered relative to the others. The ends of the hoses are conducted through conduits  109  to the underside of the planes. The sequential arrangements form a larger arrangement  101  and are arranged so that said staggered hoses  105  are staggered between the sequential arrangements, contributing to the connection between the sequential arrangements.  
         [0084]      FIG. 11  illustrates a third example with three arrangements  112 ,  113 ,  114  according to the invention in sequence to create one large arrangement  111  according to the invention. In one of the arrangements  112 , the pressure element is a compressible mat  115 , the ends of which are conducted below the top surface of the plane through the conduits  116 . The second arrangement has compressible mats  117  and hoses  119  in parallel. The plane has conduits  118 ,  1110  suitable for each pressure element. In the third arrangement  114 , the pressure elements are parallel hoses  1111 ,  1112  with conduits  1110 . The middle hoses  1112  are thinner than the other hoses.  
         [0085]     It can be concluded from the examples in FIGS.  9  to  11  that the desired number of arrangements according to the invention can be arranged in sequence. The number three is only an example.  
         [0086]     At least one pressure element  3  in an arrangement according to the invention may also include intermediate connections  121  as illustrated in  FIG. 12 . In this case the plane includes conduits  122  for intermediate connections  121 . Furthermore, the arrangement includes connectors  123  for each intermediate connection  121 , connected to the supply to the first end of the pressure element through at least one choke valve  124 . The supply of the control means  6  to the second end of the pressure element may be arranged in any of the manners described above.  
         [0087]     Connection of the intermediate connections  121  of the pressure element  3  to the supply of the control means  6  through which the pressure medium can flow into the pressure element and out of the pressure element through its first end creates an arrangement that can be used for moving sequential cylindrical objects located on the top of the pressure element. The choke valve  124  provides the desired flow of the pressure medium to the intermediate connections. It is also possible that several or all of the intervals  125  between the intermediate connections have separate choke valves.  
         [0088]     The arrangements according to the invention are suitable for cylindrical objects of different sizes (and weights). The pressure element  3  can be a compressible hose or compressible mat, and these may be arranged in parallel, staggered or sequentially. The control means  6  may be placed below or near the plane. The control means may be used to control several pressure elements if fitted with connections for each pressure element. The connections for pressure elements may comprise a spring-loaded non-return valve. Even though the examples in the figures mostly illustrate open circulations of pressure medium, control means may also be provided for closed circulations of pressure medium.  
         [0089]     The markings of the connections of the directional valves may be different than the markings illustrated in the examples in the figures. The markings of the connections are only included to facilitate description of the operation of the directional valve in relation to the other components and thus do not limit the use of a similar directional valve or another type of directional valve for the same purpose. The directional valves may also be of a different type than described in the examples. It is evident from the above that an arrangement according to the invention may be implemented in several different ways.  
         [0090]     It is also evident that the invention is not limited to the examples mentioned in this text but may be implemented in many other different embodiments within the scope of the inventive idea.