Abstract:
The invention relates to a walking aid for a mechanically driven treadmill, comprising at least one tractive element that is guided over two respective deflection rollers and that is driven directly or indirectly by means of the treadmill. The tract of said element that directly faces the treadmill belt is displaced in the same direction as said belt and the tract of the element that faces away from the belt is displaced in the opposite direction to the latter. The aid also comprises at least one fixing element, which is located on the tractive element, for supports for part of the feet and/or legs.

Description:
BACKGROUND 
     1. Technical Field 
     The present invention relates to a walking aid for a mechanically driven treadmill. 
     2. Description of the Related Art 
     Treadmill training has been successfully used for some time in the treatment of paraplegic patients and/or patients suffering from neurological damage and illnesses. A suspension device provides partial body weight relief to enable the patient to train (e.g., to walk) even if the patient is unable to walk independently or can only walk with therapeutic assistance. Training can stimulate the metabolic processes and maintain the function of the muscles and joints. 
     Even if a partial body weight relief is achieved through the suspension device, most patients generally need their feet to be placed in position by the physiotherapist. Generally, up to three physiotherapists are needed, and the treatment is physically very demanding for them. The therapist may sit when positioning the patient. On the one hand, the sitting position for the therapist is unfavorable, and there is a high load on the spinal column, so that, with this activity, therapists often complain that they are suffering from problems in various areas of the spine. 
     In addition, one disadvantage of the patients&#39; legs being moved by the therapists is that the patients&#39; feet are often not properly positioned for training. This often leads to asymmetrical movement sequences. 
     Computer-aided methods of movement control have been developed and implemented in exercise robots in order to move the patients&#39; lower extremities. Because this type of system is very expensive, its use is only possible to a limited extent. 
     DE 101 39 276 describes a walking training system having a treadmill. The walking training system has two wheels that are independent of each other and driven by the treadmill. Each wheel is provided with devices to hold a lower leg in place. An individually adjustable walking movement is transmitted to the lower extremities of the user via a sliding mechanism inserted in a longitudinal hub. The fixing device is attached to the sliding mechanism. Because the sliding mechanism can be moved within the longitudinal hub, there is a considerable risk of injury when positioning the individual lower legs, if the sliding mechanism is not in the proper position. In addition, the two wheels must be arranged exactly in relation to each other in order to ensure even movement. The walking training system has a complicated construction and is therefore expensive to manufacture and to maintain. 
     BRIEF SUMMARY 
     Some embodiments of the present invention provide a simple walking aid which produces a movement similar to natural walking. In addition, the walking aid can reduce the burden on the therapists and allows the patients to train independently on their own. 
     In some embodiments, a walking aid for a mechanically driven treadmill comprises at least one tractive element that is guided over two deflection rollers in each case and that is driven directly or indirectly by means of the treadmill. A section of the tractive element directly facing the treadmill belt moves in the same direction as the treadmill belt and a section of the tractive element facing away from the treadmill belt moves in the opposite direction of the treadmill belt. The walking aid also comprises at least one fixing element arranged on the tractive element for holding devices for the foot and/or leg area. 
     The walking aid according to some embodiments has a very simple structure. On the one hand, specific positions of the two lower legs or feet may be desired. Because the movement is achieved through a tractive element, a very even movement can be ensured. Achieving an almost natural sequence of movements is possible without needing to make any additional settings. The walking aid according to some embodiments gives the patient a desired amount of independence, since the aid of a therapist is only required to step onto the treadmill and to fix the lower legs. The therapist&#39;s work is made easier such that the therapist can care for additional patients. Because the walking aid is moved via the treadmill, an additional drive system is not necessary. 
     Automatic treadmill therapy can be used as an effective standard therapy for many motor diseases, injuries, and orthopaedically/traumatologically ill patients. For example, the automatic treadmill therapy can be used to treat hemi-tetraplegics, para-tetraplegics, spastic paralysis, multiple sclerosis, and cranio-cerebral trauma. 
     In addition, automated treadmill therapy can also be used in geriatrics to maintain the mobility of elderly people. Advantageously, the therapy, in some embodiments, can be carried out independently without any therapeutic assistance so that the treated people can retain their independence for as long as possible. 
     According to some embodiments, the walking aid can include two deflection rollers and one tractive element. This construction limits the components to a minimum. In addition, the movement of both lower legs is achieved via a single system by means of a single tractive element, thereby providing a very even movement. 
     In some embodiments, two fixing elements can be arranged at diametrically opposed positions on the tractive element. In this way, the position of the two lower legs in relation to each other is maintained so that an almost natural sequence of movements can be achieved directly without any additional settings. 
     In some embodiments, the fixing elements can have lower leg holding devices. Each of the lower leg holding devices is swivellable about an axle that is parallel to the deflection roller axle. This arrangement ensures that the movement produced by the walking aid generally corresponds to a natural movement. It also results in the vertical axle of the holding device constantly changing because of the bending of the knee and the path of travel of the tractive element. 
     According to another embodiment, the walking aid can have four deflection rollers and two tractive elements. Each tractive element engages two deflection rollers. The tractive elements are arranged parallel to each other. This provides a separate movement element for each foot or leg, the position of which can be changed independently of each other, in order to carry out other movement rhythms without any major alteration work. 
     The fixing elements extend into the space between the parallel tractive elements. The user stands between the two walking aids formed by the deflection rollers and tractive elements so that there is sufficient space to perform the desired movement. This may reduce the risk of injuries from contact with the walking aid. Both fixing elements can be arranged on the tractive element in accordance with the desired position of each leg. 
     The tractive element can be a chain and the deflection rollers can be formed as chain wheels. The chain wheels and chains provide a very simple way of producing the intended movement. The chain and chain wheel system may be easy to maintain and has been tried and tested for a long time. 
     In some embodiments, the tractive elements can be toothed belts. The toothed belt can rest directly on the treadmill in order to transfer the movement of the treadmill to the deflection rollers. Furthermore, the external surface of the toothed belt can be provided with an additional material (e.g., material affixed to the belt) which increases contact with the treadmill surface. The additional material can be, for example, a rubber strip which is applied to the toothed belt and vulcanized. The material can be interrupted so that no pulling forces arise on deflection. With this embodiment, the fixing element can be arranged on the top side of the toothed belt. Here, the deflection rollers can be coupled to a central frame. The deflection rollers can be arranged to the left and right of the patient during use. This reduces the width of the device, so that the patient&#39;s legs are not spread too far apart. 
     According to some embodiments, a drive wheel in contact with the treadmill can be assigned to at least one deflection roller. A drive wheel of this type can start the movement of the deflection rollers in a simple manner, so that the movement of the treadmill is easily transmitted to the tractive elements. 
     Advantageously, the drive wheels can be formed concentrically with respect to the deflection rollers. The diameters of the drive wheels can be substantially equal to the diameters of the deflection rollers. The drive wheels in contact with the deflection rollers have a common axle, so that the actual speed of movement of the walking aid can be determined by the diameters. 
     According to another embodiment, it can be provided that the movement of the treadmill is transferable from a drive wheel, in frictional contact with the treadmill, to a drive wheel arranged at a distance to that drive wheel and assigned to the deflection roller. Here, the treadmill movement is not transferred directly to the walking aid. Instead, the treadmill movement is transferred via a separate movement sequence that is independent of the deflection rollers. In this way, a very even movement sequence similar to a natural movement is achieved. In addition, such a walking aid is very easy to construct, install, maintain and repair, since the drive and the movement achieved via the deflection rollers are separated from each other. 
     According to a further embodiment, the drive wheel in frictional contact with the treadmill can be positioned at approximately right angles to the deflection roller. In this way, the distance between the two drive wheels is kept to a minimum so that long transmission paths are avoided. 
     Additionally, the drive wheel can be assigned to the rear deflection roller. In this way, the walking aid is stabilized on the treadmill and an even transmission of the movement is ensured. Similarly, the drive wheel can be assigned to the front deflection roller. In this way, the drive wheel can be moved away from the walking aid to, for example, exclude any contact with the patient. Furthermore, the adhesion between the treadmill and the drive wheel can be increased, because of leverage from the backwards walking aid produces a higher drive pressure between the drive wheel and the treadmill. 
     According to a further embodiment, the drive wheel in frictional contact with the treadmill can be arranged in front of the deflection roller. Because the drive wheel is arranged in front of the actual walking aid, the walking aid can be arranged very close to the treadmill. This may effect the lower tractive element tract facing the treadmill. 
     Advantageously, both drive wheels can be friction wheels. Another wheel can be positioned between the two drive wheels. The additional wheel can contact the drive wheels. The transmission of the treadmill motion via friction wheels is a very simple method of transmission; here, the additional wheel can be used to ensure that the deflection rollers are moving in the same direction as the lower drive wheel. 
     According to a further embodiment, the drive wheels in contact with the treadmill can be connected to each other via a tractive element. Various types of known transmission means, which are frequently and successfully used in practice, allow for fast, simple maintenance. 
     According to another embodiment, a guide for the holding device that is independent of the tractive element can be provided. A guide of this type ensures that the movement carried out by the holding devices is very even and exact. 
     According to a further embodiment, the fixing element can be a catch that is arranged on the tractive element such that the fixing element is fixed and cannot be rotated. Because of the catch, the holding device can be transported at a greater speed. The impetus phase, as it is called, of the leg to be transported forward may reach a higher speed. 
     Advantageously, the catch can be arranged on the side of the tractive element facing away from the deflection rollers. The catch can extend a predetermined distance from the tractive element and be formed in the longitudinal direction with a receiver slot, in which a leg brace support is arranged so that it can be moved along the receiver slot. A catch of this type has proved successful in practice. The receiver slot acts as a guide. Accordingly, the guide ensures that desired predetermined movements are achieved. 
     According to another embodiment, the walking aid can be arranged in a housing which is formed with a guide element arranged at a predetermined distance around the deflection rollers, through which the leg brace support, from the catch, can extend out of the housing. This provides a guide element in a very simple manner without additional means being necessary, since the guide element is formed inside the housing. 
     Advantageously, the guide element can be formed as a slot-shaped opening. 
     According to a further embodiment, at least the section of the slot-shaped opening facing the treadmill is substantially parallel to the treadmill, and the slot-shaped opening can extend around each of the deflection rollers at a predetermined distance. The distance and the parallel distance can be elected to produce the most even movement possible, which comes close to natural movement. Different movement patterns can be achieved through the choice of the slot shape and the position of the slot. 
     Advantageously, the slot-shaped opening around the deflection rollers is formed as a section of a circle. Here, it can be provided that the sections of the circle have different diameters. It has been proved advantageous if, in operation, the larger diameter is at the rear deflection roller. These embodiments contribute, once again, to the evenness of the movement pattern and to the achievement of different movement patterns. 
     According to a further embodiment, the housing can consist of two parallel plates. This provides sufficient protection for the user in order to reduce the likelihood of injuries from the moving parts of the walking aid. 
     Advantageously, the deflection rollers and the drive wheels can be arranged between and fixed to the two plates. This in turn simplifies the structure, since no complicated additional holding device needs to be provided. 
     According to another embodiment, a running wheel can be arranged on the housing at a predetermined distance to the front deflection roller in contact with the treadmill. This stabilizes the walking aid further, so that two support points are provided. 
     Advantageously, the support of the leg brace can be fixed so that it swivels at the leg brace receiver. This feature ensures that the lower leg is kept in the desired movement position. 
     Advantageously, a protective element can be arranged on each side of the tractive element facing away from the fixing element. This protects at least one side of the walking aid so that there is no adverse effect on the movement sequence. 
     According to a further embodiment, it can be provided that the drive wheels mesh with the deflection roller arranged on the outside of the protective element. Consequently, the individual transmissions of movements are clearly separated from each other, which again may help simplify maintenance and repair. 
     Advantageously, the walking aid can be fixable to the frame of the treadmill. This ensures a stable arrangement of the walking aid on the treadmill. For example, the walking aid can be coupled to the handrail support. 
     According to a further embodiment, it can be provided that the two deflection rollers are connected to each other via a longitudinal beam and can be fixed via the longitudinal beam to the treadmill. This represents a very simple method of fixing the walking aid. Using the longitudinal beam, the two deflection rollers are fixed relative to each other, thus providing additional safety. 
     Advantageously, a sliding sleeve can be provided in the area of the longitudinal beam so that the walking aid can be moved relative to the handle. In this way, the walking aid can be conveniently set to the height of the patient to ensure that the handle is held securely by the patient during operation of the walking aid. 
     According to a further embodiment, the walking aid can be fixable to a handrail frame of the treadmill. This ensures further stabilization of the walking aid on the treadmill. 
     It is possible to arrange the walking aid in a fixed position and only to push it on the treadmill for use. The housing can extend to a cross beam arranged between the handrail frame and is movable around the cross beam. In this way, the walking aid can be folded and stored away if it does not need to be used. The treadmill can then be used for other therapeutic purposes. 
     Advantageously, the housing can be formed with a through hole to receive the cross beam. In this case, the housing does not need to be formed with additional fixings, so that the number of necessary parts is once again reduced. 
     Advantageously, it can be provided that the walking aid is connected via the protective element to the fixed side areas of the treadmill. This specifies the position of the walking aid on the treadmill. 
     Advantageously, the axle projecting through the protective elements to fix the front end of the walking aid can be the axle for the drive wheels in frictional contact with the treadmill. Once again, this simplifies the structure of the walking aid. 
     Advantageously, the axle can extend through the drive wheels of both tractive elements. The drive wheels are connected to each other through a swivellable axle, which means that the synchronism of the tractive element with the leg brace receiver on the left and right, diametrically, is achieved. 
     According to a further embodiment, the tractive element(s) can be arranged in a housing and the fixing elements can extend through slot-shaped openings formed in the outer plates of the housing. The fixing elements are held via guide elements in the slot-shaped opening. In this way, an additional stabilization of the fixing elements inside the slot-shaped opening is achieved. This has proved advantageous if pressure is exercised on the fixing elements, for example. At the same time, the play of the fixing elements within the slot-shaped opening is minimized. 
     Advantageously, each guide element can extend through the slot-shaped opening and comprise flat elements that are substantially parallel to the inside and outside walls of the external plates. Guide elements are very easy to manufacture and offer sufficient stability during use. 
     Each fixing element can be assigned two guide elements, which extend, in each case, through one of the parallel plates. In this case, one guide element is formed on the fixing element, whereas the second one extends, on the side facing away from the fixing element, into the opposite slot. In this way, the fixing element is securely held and, at the same time, any unilateral pressure exerted on the tractive element is minimized. 
     Advantageously, two tractive elements can be formed in the housing. An inner guide with a slot-shaped opening can be arranged between the tractive elements. The guide arranged on the side of the tractive element facing away from the fixing element can reach into the slot-shaped opening of the inner guide. Here too, stabilization is provided on both sides of the tractive element. Stabilization on the side of the tractive element facing away from the fixing element is, however, provided in the inside of the housing and is thus not visible. This means that any risk of injury by the second guide element can be reduced or eliminated. 
     Advantageously, two inner guides can be parallel with each other. 
     In addition, it can be provided that the leg brace is formed with an automatically locking closure. This embodiment helps the user to remain independent of any therapist, since the leg brace can be clicked automatically into place and can be unlocked without any manual intervention. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         FIG. 1  is a side view of a walking aid placed on a treadmill, according to one illustrated embodiment. 
         FIG. 2  is a front view of the walking aid shown in  FIG. 1 . 
         FIG. 3  is a partial sectional view of a walking aid, according to one illustrated embodiment 
         FIG. 4  illustrates the walking aid in  FIG. 3 , wherein the walking aid is arranged on a treadmill for the start of operation. 
         FIG. 5  illustrates the walking aid in  FIGS. 3 and 4  in a folded back state. 
         FIG. 6  is an isometric view of a walking aid, according to one illustrated embodiment. 
         FIG. 7  is a front view of the walking aid in  FIG. 6 . 
         FIG. 8  is a cross-sectional view of the walking aid, according to another embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The walking aid  1  shown in  FIG. 1  comprises two drive wheels  2  arranged next to each other at a predetermined distance. Here, the drive wheels  2  can be coated with rubber in order to ensure the quietest possible movement on the treadmill. 
     Each drive wheel  2  is assigned a chain wheel  3 . The drive wheels  2  and respective chain wheels  3  are connected in such a way that the movement of the drive wheel  2  is transmitted to the chain wheel  3 . As shown in  FIG. 2 , the drive wheel  2  and the chain wheel  3  are almost the same size and connected to each other via a common axle. 
     The two chain wheels  3  are connected to each other via a chain  4  and act as deflection rollers. The chain  4  runs between the chain wheels  3  and can be substantially parallel to the walking surface of the treadmill  10 . 
     If the treadmill  10  is set in motion, the drive wheels  2  start to move at the same time. The movement of the drive wheels  2  is transmitted to the chain wheels  3 . The chain wheels  3  drive the chain  4 . The section of the chain  4  facing the treadmill is moved in the same direction as the walking surface of the treadmill and a section of the chain  4  facing away from the walking surface of the treadmill in the opposite direction of the walking surface of the treadmill. In the illustrated embodiment, the section of the chain  4  facing away from the treadmill  10  may deflect downwardly (e.g., sag). 
     As shown in  FIG. 2 , a holding device for a lower leg in each case is arranged at two opposing positions of the chain (not shown in  FIG. 2 ). The positions can be diametrically opposite to each other. The holding device can be at the bottom for the leg to be moved backwards, and another holding device can be at the top for the leg to be moved forward. 
     Each lower leg holding device comprises a leg brace device  6  with a leg cuff  7 , which is connected to the chain  4 . Here, the point of fixation of the leg brace device  6  is formed at the chain  4  as swivel point  8 , so that the leg brace device can be swivelled around the movable swivel point  8 . In this way, an almost natural movement sequence is achieved when the chain  4  is moved. In this respect, the swivel point  8  can also be formed at a predetermined distance from the chain in order to, for example, prevent any possible risk of injury by the chain. 
     In operation, the legs of the patient are fixed via respective leg cuffs  7  to the leg brace devices  6 . When the treadmill  10  is set in motion, the patient&#39;s lower legs fixed in the leg brace devices  6  are moved via the movements transmitted from the drive wheels  2  to the chain wheels  3  and thus to the chain  4 . Here, the leg on the walking surface, i.e., the leg moved by the lower section of the chain, is moved backwards. That section of the chain is moved around the rear chain wheel  3  and then travels towards the front chain wheel  3  (i.e., in the opposite direction to the direction of the track of the treadmill  10 ). The other leg moved by the section of the chain facing away from the treadmill  10  is moved via the front chain wheel  3  downwards towards the walking surface of the treadmill and then moved backwards. This achieves an even walking movement, the speed of which can be regulated via the speed of the treadmill walking surface. 
     To fix the walking aid  1  on the treadmill  10 , the two drive wheels  2  of the walking aid are connected to each other via a longitudinal beam  9  which projects beyond the front drive wheel  3  and has a fixing device  11  at its front end. Using this fixing device  11 , the walking aid  1  can be fixed to the handrail support  12  of the treadmill  10 . In this way, the walking aid  1  can be fixed at the distance from the handle that suits the patient. 
     In addition, in the section of the longitudinal beam  9  between the handrail support  12  and the front drive wheel  3 , a sliding sleeve  13  is configured to allow the position of the walking aid  1  to be changed in relation to the handrail support  12  and thus to the handle, so that the walking aid can be set to suit the height of the patient. The sliding sleeve  13  also has the function of arranging the walking aid  1  on the treadmill after the patient is in a vertical position on the treadmill. A patient can be conveniently taken to the treadmill in a wheelchair and brought into a vertical position using a load relief system, especially if the walking aid arranged on the treadmill would be a disturbance in the patient&#39;s preparatory phase. 
     Another embodiment of the walking aid is shown in  FIG. 3 . Similar elements of the walking aid are designated with the same reference symbols in  FIGS. 1 and 2 . 
     The walking aid  1  shown in  FIG. 3  comprises two adjacent deflection rollers  3  arranged at a predetermined distance to each other. In this respect, the two deflection rollers  3  are chain wheels and are connected to each other via a chain  4 . The two deflection rollers  3  are arranged inside a housing. The housing includes two plates  14 ,  15 . Although not shown, in operation the plates  14 ,  15  are connected to each other via a connecting element, at least in the areas facing away from the treadmill  10 , thus closing the housing. 
     A drive wheel  16  is assigned to one of the two deflection rollers  3  and is arranged roughly vertically underneath the deflection rollers  3 , near to the areas of plates  14 ,  15  facing the treadmill. The drive wheel  16  is formed in such a way that the running surface of the drive wheel projects beyond the housing. The running surface can be coated with rubber in order to ensure the quietest possible movement on the treadmill. 
     In operation, the drive wheel  16  directly rests on the treadmill  10  and is set in motion through the movement of the treadmill. Furthermore, the drive wheel  16  has on one side a toothed wheel and is connected via this toothed wheel and a chain  17  arranged on this to a second drive wheel, which is not shown. This second drive wheel can be parallel to the drive wheel  16  and coupled to an axle with the deflection roller  3  and has approximately the same diameter as the deflection roller  3 . The movement transmitted from the drive wheel  16  via the chain  17  to the second drive wheel is directly to the deflection roller  3 . In this way, the chain  4  extending between the deflection rollers  3  is also set in motion. The second drive wheel can also be formed as a component with the deflection roller  3 . At two positions on the chain  4  opposite each other, a catch  18  is fixed in each case which is coupled directly to individual chain links via bolts so that it cannot be moved or swivelled. The connection can be made using rivets, for example. Here, the catch  18  is formed as a longitudinal element, which has a receiver slot  19  formed in a longitudinal direction. The catch  18  extends in the direction of the chain  4  facing away from the deflection rollers  3  and can preferably have an angle element near the chain, for stabilization, in order to be arranged stably at two points of the chain. 
     A leg brace receiver  20  is inserted into the receiver slot  19  of the catch  18  and can be moved along the receiver slot. 
     Each of the housing plates  14 ,  15  can be formed with a guide in the form of a slot-shaped opening  21 . In this respect, this slot-shaped opening  21  at a predetermined distance around the chain  4 . The precise positioning of the slot-shaped opening  21  can vary. In some embodiments, the area of the slot-shaped opening  21  facing the treadmill can be arranged substantially parallel to the treadmill. In the area of the deflection rollers  3 , the slot-shaped opening  21  is formed mostly as a segment of a circle, whereby the individual circle segments opposite each other can have different diameters. If the circle segments have different diameters, the circle segment near the rear deflection roller  3  can be larger than the other circle segment. In this case, the substantially straight section facing away from the treadmill  10  extends downwards at an angle. 
     The shape and configuration of the slot-shaped opening  21  can be selected based on the required movement pattern. The leg brace receiver  20  extends through the receiver slot  19  of the catch  18  into the opening  21  and is preferably formed larger on the inside of the housing plate  14 ,  15  or is held by a fixing element on the inside of the housing plate  14 ,  15  to prevent the leg brace receiver  20  from slipping out of the slot-shaped opening  21 . 
     If the treadmill is set in motion, the drive wheel  16  starts to move. The movement of the drive wheel  16  is transmitted via the chain  17  to the second drive wheel and thus to the deflection rollers  3  and the chain  4 . The moving chain  4  carries the catch  18  and defines a fixed movement around the chain  4 . The leg brace receiver  20  arranged inside the receiver slot  19  of the catch  18  is simultaneously moved by the catch  18  and thereby describes the movement determined by the slot-shaped opening  21 . Because the leg brace receiver  20  is inside the receiver slot  19 , the leg brace receiver can be moved in the longitudinal direction based on the position of the housing opening  21 . 
     In operation, the leg brace is fixed in such a way at one end of the leg brace receiver  20  (e.g., at the end of the leg brace receiver  20  facing away from the housing) such that the leg brace can be swivelled around the leg brace receiver  20  in order to ensure that the lower leg of the user is always in a position corresponding to the desired movement. 
       FIGS. 4 and 5  show the walking aid illustrated in  FIG. 3  mounted on the treadmill. With the embodiment shown, an additional wheel  22  is between the two plates  14 ,  15  of the housing. The wheel  22  only has a stabilizing function for the walking aid and is not connected to the deflection rollers  3  or the chain  4 . Because the drive wheel  16  is located at the rear end of the walking aid, the additional wheel  22  is arranged near the front deflection roller, for example, between the front deflection roller  3  and the rear drive wheel  13  and also rests on the treadmill  10 . 
     For positioning the walking aid  1  on the treadmill  10 , the plates  14 ,  15  of the housing project at their front end beyond the front deflection roller and are connected at their front end to a holding device fixed to the handrail frame  23  of the treadmill  10 , and in particular to the cross beam  24 . The cross beam  24  extends through openings provided in the plates  14 ,  15 . 
     As shown in  FIG. 5 , the walking aid can fold upwardly so that the treadmill  10  can also be used for other applications. 
       FIGS. 6 and 7  show yet another embodiment of a walking aid according to one illustrated embodiment. 
     The walking aid  1  includes four deflection rollers  3 . Two chains  4  connect respective pairs of deflection rollers  3 . Each pair of connected deflection rollers  3  is arranged in parallel opposite each other, and each chain  4  is provided with a catch  18  for a leg brace support. The two catches  18  are arranged on sides of the chains  4  facing each other. Here too, the catches  18 , as shown in  FIG. 7 , are arranged at positions diametrically opposed to each other. 
     In contrast to the embodiments shown in  FIGS. 1 and 3 , each foot of the patient is fixed to a catch  18  that can be moved through a separate movement sequence. Each catch  18  can be set separately. In this way, various types of movement sequences can be simulated by the walking aid. The arrangement of the axles of the drive wheels, however, can ensure synchronism of the tractive element. 
     The deflection rollers  3  are fixed to the inside of plate-shaped protective elements  25 ,  26  so that a sufficient stabilization of the deflection rollers is achieved. At the same time, the walking aid is fixed via the protective elements  25 ,  26  both at the front and at the rear to a handrail support  12  on the treadmill  10 . 
     The walking aid is moved by two drive wheels  16  spaced apart from the front deflection roller  3 ; these drive wheels  16  rest directly on the treadmill  10  and are formed with a rubber coating. In this respect, the drive wheels  16  are also arranged on the inside of the protective elements  25 ,  26 . The moving surface  5  of the treadmill  10  causes rotation of the drive wheel  16 . The movement of each drive wheel  16  is transmitted via a chain wheel  27  to a chain wheel  28  coupled to the front deflection rollers  3 . The chain wheel  28  corresponds to the drive wheel assigned to the deflection roller  3 . The transmission between each chain wheel  27  assigned to the drive wheel  16  and the chain wheel  28  assigned to the deflection roller  3  is carried out via a chain  29 . 
     Here, both the chain wheels  27 ,  28  assigned to the drive wheels  16  and to the deflection rollers  3  are arranged on the outside of the protective elements. The drive wheels  16  and the chain wheels  27  have a common axle. This axle extends outwardly from both sides of the protective elements  25 ,  26  and, at the same time, forms the holding device of the walking aid on a treadmill frame. 
     With the illustrated walking aid, the patient is positioned between the two deflection rollers  3 . The leg brace supports are fixed to the catches  18  pointed towards the patient. 
     Another embodiment of the walking aid is shown in  FIG. 8 . The walking aid comprises two tractive elements  4 , arranged parallel to each other. The tractive elements  4  are disposed inside a housing. Leg brace catches extend from respective tractive elements  4  to the outside through a slot-shaped opening  21  formed inside the relevant outer plate  14 ,  15 . With this embodiment, the walking aid can be positioned between the patient&#39;s legs. 
       FIG. 8  shows a sectional view of the walking aid. The leg brace catch  18  can be further stabilized by a guide element  30  inside the slot-shaped opening  21 . Each guide element  30  extends through the slot-shaped opening  21  and is formed on the outside and inside of each plate  14 ,  15  as a flat element, which extends parallel to the plate  14 ,  15  and is formed larger than the slot-shaped opening. The guide elements  30  can help guide the movement of the leg brace catch  18 , so that any pressure exerted on the leg brace catch can be better absorbed. A guiding member in the housing is between the two tractive elements  4 . The guiding member comprises a plate and a slot-shaped opening  31 . Through this inner slot-shaped opening  31  extends an inner guide element  32 , which extends as an extension of each leg brace catch  18  beyond the tractive element  4  inwards into the housing. This produces additional stabilization of the leg brace catches. 
     A similar stabilization is also possible with the embodiment shown in  FIGS. 3 to 5 . Here, corresponding guide elements  31 ,  32  can extend through the slot-shaped openings  21  of both plates  14 ,  15 . With this embodiment, both the leg brace catch  18  and guide  31  and guide  32  of the opposite leg brace catch consequently run in each slot. 
     With all the walking aids described above, it is possible to design the holding devices of the leg braces in such a way that the patient wears a specially formed shoe with a snap closure mechanism that can be suspended in the leg brace support. This allows the patient to start the treadmill therapy independently without the aid of a therapist.