Abstract:
A safety arrangement for a device such as a baby carriage, wheelchair or the like, having an actuator apparatus including first and second relatively displaceable parts movable between a first and second position. When the first part is arranged, in the first position it actuates a brake, and in the second position causing the brake to be in a non-braking state. The actuator is arranged, in the absence of external influence, to adopt the first position. A locking member is releasably attachable to the actuator for locking the first part in the second position, and unlocking of the first part in the second position upon application of a force. The first part is rotatable relative to the second part about a axis for displacement between the first and the second position, and includes a retaining mechanism arranged to connect the locking member to the actuator.

Description:
TECHNICAL FIELD 
       [0001]    The invention relates to a safety arrangement for a device such as a baby carriage, a wheelchair or the like. The safety arrangement comprises an actuating means having a first and a second part and a releasably attached locking means. The first and the second part are displaceable relative to one another and can adopt a first and a second position, in which first position the actuating means actuates a brake arrangement in such a way that it is in a braking state. The locking means can lock the actuating means in the second position of the first part, in which the actuating means is in a non-braking state. 
       BACKGROUND OF THE INVENTION 
       [0002]    Baby carriages, wheelchairs and similar carriages are often equipped with a brake, by means of which the carriage can be braked when in its stationary position. In most cases, however, baby carriages and wheelchairs are not equipped with any brake capable of braking the carriage in the event of the person pushing the carriage losing control over it. For example, the carriage may roll away uncontrollably if the person pushing the carriage falls, or if a person stops the carriage on an uneven surface and fails to notice that the carriage is rolling away. This can give rise to danger for the child or the person sitting in the carriage or the wheelchair. 
         [0003]    One solution is to provide the carriage with a so-called dead man&#39;s handle, that is to say a handle which must be kept depressed to ensure that the brake does not adopt its locked position. In the long run, however, it may be demanding to have to keep a handle constantly depressed in order for the carriage to be free to move. 
         [0004]    One solution which reduces the disadvantages associated with a dead man&#39;s handle is described in GB 1 377 168. This document describes a brake for a baby carriage having a brake handle mounted on the handle of the baby carriage. A clamp can be secured around the brake handle so that it is kept depressed in the position in which the brakes are not applied. A strap is attached at one end to the clamp, and its other end is passed around the wrist of the person pushing the carriage. If the person pushing the carriage were to fall, the person will pull on the strap, thereby causing the clamp to be released from the brake handle and causing the brakes to be applied. 
         [0005]    Another similar solution is described in SE 522 740. Described in this document is a safety arrangement, in which a collar device bears against a spacer. When the collar device is kept held up by the distance piece, the safety arrangement is in a non-braking state. Arranged in the distance piece is a strap, which at its other end is attached to the person pushing the baby carriage. If this person were to fall, for example, or if the carriage were to roll uncontrollably down an incline, the person will pull on the strap, thereby causing the spacer to be released from the safety arrangement and the collar device to drop down and apply the brake. 
         [0006]    In the solutions described above, a safety arrangement for braking the baby carriage is activated when a user actuates a locking device in the form of a clamp and a spacer, respectively, with sufficiently great force. 
       SUMMARY OF THE INVENTION 
       [0007]    In the light of the above, one object of the present invention is to provide an improved safety arrangement for a device such as a baby carriage, a wheelchair or the like. 
         [0008]    More precisely, a safety arrangement comprising an actuating means comprising a first part and a second part, the first part being displaceable relative to the second part between a first position and a second position, is provided for a device such as a baby carriage or a wheelchair. The actuating means is arranged, in the first position of the first part, to actuate a brake arrangement so that it is in a braking state, the actuating means, in the second position of the first part, being arranged to actuate the brake arrangement so that it is in a non-braking state. The first part is arranged, in absence of external influence, to adopt the first position. The safety arrangement further comprises a locking means being releasably attachable to the actuating means for locking the first part in the second position, the locking means being arranged to cease said locking of the first part in the second position by application of a predetermined force. The first part is rotatable relative to the second part about a geometrical axis for displacement between the first and the second position. The actuating means includes a retaining means which is arranged, upon releasable attachment of the locking means to the actuating means, to connect the locking means to the actuating means, the retaining means being arranged, by application of said predetermined force, to maintain the connection of the locking means to the actuating means until the first part has adopted the first position and then to release the locking means from the actuating means. 
         [0009]    The application of a predetermined force denotes the actuation of the locking means with a force exceeding a predetermined threshold value and in a predetermined direction. 
         [0010]    One advantage of the present invention is that the locking means ceases its locking of the first part in the second position by application of a predetermined force. A person, referred to below as the person pushing, pushes the device, such as a baby carriage or wheelchair, also referred to below as the carriage, can be caused to actuate the locking means with a force if the person pushing falls, stumbles, loses control of the carriage on a slope or stairway, etc., by connecting the person pushing the carriage to the locking means with a strap or the like. As a result of this, the first part returns to the first position, in which the actuating means actuates the brake arrangement so that it adopts its braking position. A person pushing who loses control of a carriage equipped with the safety arrangement according to the invention actuates the locking means with a predetermined force, for example by falling or stumbling or by the carriage running away on a downhill slope or down a flight of stairs. When the locking means is actuated by a predetermined force, locking of the first part in the second position ceases and the first part instead adopts its first position. In this first position, the actuating means actuates the brake arrangement so that it adopts its braking position. The carriage will thereby be braked. This prevents the carriage from running away in a situation, in which the person pushing no longer has control of the carriage. If, for example, the person pushing tumbles down a steep downhill slope, the carriage will not continue to run away but will be braked by the safety arrangement. In a situation, in which the person pushing leaves the carriage in the belief that the carriage will remain stationary, but it begins to roll because of the inclined nature of the surface, the safety arrangement will brake the carriage and prevent its movement. 
         [0011]    Another advantage of the safety arrangement is that it offers extra security. In the event that the safety arrangement has been subjected to an influence such as an accident, wear or a manufacturing fault, which means that the first part is unable to reach its first position, the person pushing will not be released from the carriage. The retaining means maintains the connection between the locking means and the actuating means until the first part has adopted its first position. Once the first part has adopted its first position, in which the brake arrangement is in its braking state, the locking means is released from the retaining device. In this way, the person pushing is not released from the safety arrangement until the brake arrangement brakes the carriage. In the event that the first part does not adopt its first position, the person pushing will still be connected to the carriage and will thus have the opportunity to stop the carriage. This prevents a situation in which the safety arrangement fails to activate the brakes at the same time as the person pushing completely loses control of the carriage. 
         [0012]    A further advantage is that the safety arrangement exhibits a simple construction comprising few parts, this being advantageous from the point of view of manufacturing and costs. The safety arrangement is also easy to retrofit to a carriage which lacks any such safety arrangement. 
         [0013]    The second part may comprise a section which is situated radially externally relative to the first part. The locking means is thus capable of being passed through said section and into contact with the first part to permit its releasable attachment to the actuating means. The second part thus guides the locking means into engagement with the actuating means. 
         [0014]    The locking means may be arranged to engage with the first part for locking the first part in the second position. 
         [0015]    The retaining means may comprise a projection arranged to engage with the locking means. The projection may engage with a recess in the locking means. 
         [0016]    The retaining means may be resilient. This allows the locking means to be moved out of its engagement with the actuating means, for example by the person pushing the carriage pulling on the locking means, so that locking of the first part can cease. Maintenance of the connection of the retaining means to the locking means is permitted at the same time. 
         [0017]    The retaining means may be arranged for guiding the locking means for locking the first part in the second position. It is sufficient for the person pushing to introduce the locking means into the actuating means so that the retaining means engages with the locking means. The retaining means then guides the locking means into engagement with the first part. 
         [0018]    The first part may comprise a step arranged to engage with the locking means for locking the first part in the second position. The interaction of the locking means with the step locks the first part in the second position by preventing rotation of the first part. 
         [0019]    The locking means may comprise a pin arranged to engage with a recess in the actuating means for locking the first part in the second position. The person pushing can be connected to the pin by means of a strap so that, when the user pulls on the pin, locking of the first part in the second position ceases. 
         [0020]    The retaining means may be formed by a groove which is defined by the first and the second part. The engagement of the locking means with the actuating means will be maintained for as long as the locking means is inserted into the groove. 
         [0021]    The pin may be arranged, by application of said predetermined force, to cease its engagement with the recess in the actuating means. 
         [0022]    The safety arrangement may also comprise a strap arranged to be connected to the locking means and the person pushing the device. The person pushing may have the strap secured around his/her wrist or to his/her belt, for example. In the event of the person pushing losing control of the baby carriage, the person pushing will actuate the strap, as a result of which the locking means will be pulled automatically out of its engagement with the first part. 
         [0023]    The locking means may be insertable into the actuating means in a radial direction. 
         [0024]    Said predetermined force, the level of which may exceed a predetermined threshold value, may be oriented in a radial direction away from the actuating means. 
         [0025]    One or other of the first and the second parts may comprise a handle part which is rotatable about said geometrical axis in order to bring the actuating means to the second position of the first part. The handle part facilitates rotation of the first part to its second position. 
         [0026]    The safety arrangement may also comprise a wire connected to the actuating means and the brake arrangement. 
         [0027]    The actuating means may be actuated by a spring force in order to cause the first part, in the absence of external influence, to adopt the first position. 
         [0028]    The first part may be displaceable relative to the second part between said first position, said second position and a third position, the actuating means in the third position of the first part being arranged to actuate said brake arrangement or an additional brake arrangement so that the brake arrangement is in a braking state. The safety arrangement in the third position thus functions as a conventional handbrake for braking the baby carriage, for example on downhill slopes. The safety arrangement thus provides a further function. In the third position, the safety arrangement functions as a handbrake for use when pushing the baby carriage along. 
         [0029]    The first, second and third positions may be arranged as to follow one after the other in a continuous rotational movement. 
         [0030]    A baby carriage comprising a safety arrangement is provided according to another aspect of the invention. The advantages described above are also applicable to this aspect of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    Embodiments of the present invention are described below by way of illustration with reference to the accompanying drawings. 
           [0032]      FIG. 1  depicts a baby carriage chassis comprising a safety arrangement. 
           [0033]      FIG. 2  depicts schematically a safety arrangement according to a first embodiment of the present invention, in which a first part is in a first position. 
           [0034]      FIG. 3  depicts schematically the safety arrangement in  FIG. 2 , in which the first part is in a position between the first and the second position. 
           [0035]      FIG. 4  depicts schematically the safety arrangement in  FIG. 2 , in which the first part is in a second position. 
           [0036]      FIG. 5  depicts schematically the safety arrangement in  FIG. 2 , in which the first part is in a position between the second and the first position. 
           [0037]      FIG. 6  depicts schematically the safety arrangement in  FIG. 2 , in which the first part is again in the first position. 
           [0038]      FIG. 7  depicts schematically the safety arrangement in  FIG. 2 , which has once again reached the starting position. 
           [0039]      FIG. 8  depicts a safety arrangement according to a second embodiment of the present invention. 
           [0040]      FIGS. 9 and 10  depict the locking means in more detail. 
           [0041]      FIG. 11  depicts schematically the safety arrangement in  FIG. 8 , in which the first part is in a first position. 
           [0042]      FIG. 12  depicts schematically the safety arrangement in  FIG. 8 , in which the locking means has been introduced into a groove in the actuating means. 
           [0043]      FIG. 13  depicts schematically the safety arrangement in  FIG. 8 , in which the first part is in a second position. 
           [0044]      FIG. 14  depicts schematically the safety arrangement in  FIG. 8 , in which the first part is again in the first position. 
           [0045]      FIG. 15  depicts schematically a safety device according to a third embodiment of the present invention. 
           [0046]      FIG. 16  depicts schematically the safety arrangement in  FIG. 15 , in which the first part is in a third position. 
           [0047]      FIG. 17  depicts schematically a device without a locking means. 
       
    
    
     DETAILED DESCRIPTION 
       [0048]    Embodiments of a safety arrangement  1  according to the present invention are described below in conjunction with their use on a baby carriage  2 . 
         [0049]    Depicted schematically in  FIG. 1  is a chassis for a baby carriage  2  having a safety arrangement  1  according to a first embodiment. The depicted baby carriage  2  has four wheels  5 , although it can also have three or any other number of wheels. The safety arrangement  1  comprises an actuating means  10  and a locking means  3 . The actuating means  10  is mounted on a handle part  4  of the baby carriage  2 . The actuating means  10  is appropriately positioned so that it is easy for the person pushing to reach. The expression person pushing is used below to denote a person who pushes along the baby carriage, the wheelchair or a similar device provided with the safety arrangement  1 . A strap  6  is connected to the locking means  3 . The person pushing can be connected to the strap  6 . The strap  6  can be terminated with a loop, for example, that the person pushing places around his/her wrist. Alternatively, a hook can be arranged at the free end of the strap  6 . The hook can be attached to the person pushing, for example to his/her belt. 
         [0050]    The baby carriage  2  is provided with a brake arrangement  8 . Arranged between the actuating means  10  and the brake arrangement  8  is a wire  7 . In the illustrated embodiment, the brake arrangement  8  comprises two brake elements  8 , one brake element  8  on one rear wheel  5  and one brake element  8  on the other rear wheel  5 . A person skilled in the art will appreciate that the invention can be realized with a single brake element, and that the brake element can be arranged alternatively on another wheel, for example on a front wheel. Each brake element in the depicted example consists of a pin  9  which is pushed into the wheel  5  between its spokes in order to prevent rotation of the wheel  5  by braking. A person skilled in the art will appreciate that the braking effect can be achieved in a variety of different ways, for example by means of a disc brake, a drum brake or brake blocks which act upon the wheel or the wheel axle, or with a magnetic brake. 
         [0051]    As an alternative, instead of the wire  7 , the brake arrangement  8  can be controlled by the electric transmission of a signal. 
         [0052]    The actuating means  10  can adopt two positions, one position in which the actuating means  10  actuates the brake arrangement  8  so that it is in a braking state, and a second position in which the actuating means  10  actuates the brake arrangement  8  so that it is in a non-braking state. In the absence of external influence, the actuating means  10  will attempt to adopt the first position, that is to say the position, in which the brake arrangement  8  brakes the baby carriage  2 . 
         [0053]    A first embodiment of the safety arrangement  1  is now described in more detail with reference to  FIGS. 1 and 2 . The actuating means  10  of the safety arrangement  1  comprises a first part  11  in the form of a handle and a second part  12  in the form of a seat for a base of the handle. The first part  11  is displaceable relative to the second part  12  between a first and a second position. More precisely, the first part  11  is rotatable relative to the second part  12  about a geometrical axis for displacement between the first and the second position. The actuating means  10 , in the first position of the first part, actuates the brake arrangement  8  via said wire  7  (not depicted in  FIG. 2 ) so that it is in a braking state. In the second position of the first part, the actuating means  10  actuates the brake arrangement  8  so that it is in a non-braking state. The wire  7  can be spring-loaded. The first part  11  attempts to adopt the first position in the absence of external influence. For example, the actuating means  10  can be spring-loaded so that the first part attempts to adopt the first position. 
         [0054]    In the depicted embodiment, the second part  12  exhibits a section which is situated radially externally relative to the first part. The second part  12  thus at least partially encloses the first part  11 . 
         [0055]    The first part  11  is also provided with a handle part  13 . The handle part  13  extends radially outwards from the first part  11  through an opening in the section of the second part  12 . The handle  13  is so arranged as to facilitate rotation of the first part  11  from the first position to the second position. A person skilled in the art will appreciate that the handle part can be configured in many different ways. For example, the handle part can be in the form of a knob. 
         [0056]    The first part  11  also comprises a step  14 , the function of which will be described below. In the depicted embodiment, the first part  11  comprises a retaining means  15 . In the depicted embodiment, the retaining means  15  is in the form of a projection  16 . The projection  16  extends in the circumferential direction, but it may have a different radius than the first part  11 . The projection  16  is resilient, for example as a result of the removal of material from the projection. The retaining means  15  may be made of plastic or metal. 
         [0057]    The second part  12  is provided with a recess  17 , through which the locking means  3  can be inserted into the actuating means  10 . The second part  12  can also be provided with fixing means  19  for attachment of the actuating means  10  to the baby carriage  2 . 
         [0058]    The locking means  3  is provided with a recess  18 . The recess  18  is intended to receive the retaining means  15  when the locking means  3  is inserted into the actuating means  10 . Attached to one end of the locking means  3  is a strap  6 , which strap  6  is intended to be attached to the person pushing. The other end of the locking means  3  is intended to engage with the step  14  on the first part  11  when the locking means  3  is inserted into the actuating means  10 . 
         [0059]    The first part  11  and the second part  12  may be made of plastic. The handle part  13  and the locking means  3  may also be made of plastic. 
         [0060]    In  FIGS. 1 and 2 , the actuating means  10  is in its first position, in which the actuating means  10  actuates the brake arrangement  8  so that it is in the braking state. The baby carriage  2  is braked in this way. 
         [0061]    In  FIG. 3 , to which reference is now made, displacement of the first part  11  begins by rotation from the first position to the second position. The rotating movement takes place in a clockwise direction in the depicted embodiment. The person pushing now wishes to move the baby carriage forwards and must release the brake arrangement  8  in order to do this. The person pushing takes hold of the handle part  13  and rotates the first part  11  of the actuating means  10  towards the second position. The person pushing must then overcome the force which causes the first part  11  to attempt to adopt the first position. 
         [0062]    The locking means  3  is insertable into the locking means  10 , for example in a radial direction. Before or in conjunction with the commencement of the displacement through rotation, the locking means  3  is inserted into the actuating means  10  through the recess  17  in the second part  12 . The actuating means  10  can also be provided with guide elements, for example in the form of steps, for guiding the locking means  3  into the actuating means  10  in the right direction. When the rotating movement commences, the first part  11  comes into a position in which the retaining means  15  engages with the recess  18  in the locking means  3 . In the case where the retaining means  15  is a projection  16  arranged on the first part  11 , the projection is moved into the recess  18  of the locking means  3 . In one embodiment, the projection  16  is configured in such a way that the rotating movement causes the projection  16  to guide the locking means  3  further in towards the centre of the first part  11  for engagement with the first part  11 . 
         [0063]    Further rotation of the first part  11  towards the second position will cause the resilient retaining means  15  to press an end surface of the locking means  3  towards a guide surface on the first part  11 . Said step  14  is formed on said guide surface and, once the first part  11  has reached the second position, the end surface of the locking means  3  will have passed said step  14 , as depicted in  FIG. 4 . In this second position, the engagement of the locking means  3  with the step  14  counteracts the attempt by the first part  11  to adopt the first position. The locking means  3  thus locks the first part  11  in the second position, in which the brake arrangement  8  adopts its non-braking position. The baby carriage  2  is thus able to roll freely without the person pushing being required to take hold of the handle part  13  in order to release the brake arrangement  8 . 
         [0064]      FIG. 5  depicts a situation, in which the person pushing actuates the locking means  3  with a predetermined force, for example as the result of losing control of the baby carriage  2  for some reason and thereby actuating the strap  6  which connects the person pushing to the locking means  3 . Examples of such situations can be that the person pushing stumbles and falls, that the person pushing is unable to withstand the force of inertia on a steep downhill slope or down a flight of stairs, or when the person pushing leaves the baby carriage in the belief that the baby carriage will remain stationary, but it begins to roll in spite of this. 
         [0065]    In this position, the person pushing actuates the locking means  3  with a force exceeding a predetermined threshold value in a direction away from the actuating means  10 . A person pushing who falls, for example, will pull the locking means  3  out of its locking position. The locking means  3  thus ceases its engagement with the step  14 . As a result, the locking means  3  ceases its locking of the first part  11  in the second position. The first part  11  will thus attempt to adopt its first position because it is no longer being acted upon by any external force. For example, the actuating means  10  can be spring-loaded so that the first part attempts to adopt the first position in the absence of external influence. 
         [0066]    As depicted in  FIG. 6 , the locking means  3  no longer engages with the step  14 . However, the retaining means  15  continues to engage with the recess  18  in the locking means  3 . The resilient characteristics of the retaining means  15  permit the locking means  3  to cease its engagement with the first part  11 , while the connection of the retaining means  15  to the locking means  3  is maintained. The retaining means  15  maintains its connection with the locking means  3  during displacement of the first part  11  from the second position to the first position. The retaining means  15  does not release the locking means  3  from the actuating means  10  until the first part  11  has adopted the first position. 
         [0067]    In the depicted embodiment, the projection  16  maintains its engagement with the locking means  3  during the rotating movement until the first part  11  adopts the first position. Once the actuating means  10  has adopted its first position, the locking means  3  is released from the projection  16 . As a result, the locking means  3  is also released from the actuating means  10 . In this first position, as depicted in  FIG. 6 , the actuating means  10  actuates the brake arrangement  8  so that it adopts its braking state. Once the first part  11  has reached its first position, the baby carriage  2  is thus braked. 
         [0068]    In the position depicted in  FIG. 7 , the baby carriage  2  is braked and the person pushing is released from the baby carriage. 
         [0069]    The retaining means  15  acts as extra security in the sense that the locking means  3  is not released from the actuating means  10  until the first part  11  has reached its first position, in which the brake arrangement  8  is in its braking state. In the event that the first part  11  does not reach its first position, the locking means  3  is not released from the actuating means  10 . Thus, the person pushing is also not released from the baby carriage  2 , and the baby carriage  2  cannot run away out of control. 
         [0070]    When the person pushing then wishes to release the brake arrangement  8  again, the person pushing once again turns the actuating means  10  to its second position and inserts the locking means  3  in accordance with what was previously described above with reference to  FIGS. 2-4 . 
         [0071]    A second embodiment of the present invention is described with reference to  FIGS. 8-14 . Similarly to what has been described previously with reference to  FIG. 1 , a safety arrangement  1  is arranged on a chassis for a baby carriage  2  or the like. For example, the safety arrangement  1  can be arranged on a handle part of the baby carriage  2 . In the manner described above, the safety arrangement  1  is connected to a brake arrangement in accordance with what has been described in conjunction with the first embodiment. 
         [0072]    As previously, the safety arrangement  1  comprises an actuating means  10 ′ and a locking means  30 . The actuating means  10 ′ can be attached, for example, to a handle part on the baby carriage by means of fixing means  19 . A brake arrangement  8 , which is arranged on the baby carriage  2 , comprises brake elements which act upon one or more wheels of the baby carriage. Arranged between the brake arrangement  8  and the actuating means  10 ′ is a wire  7 . Alternatively, the connection between the actuating means  10 ′ and the brake arrangement  8  can take place in some other way, for example by means of electrical transmission. 
         [0073]    The locking means  30 , which is illustrated in more detail in  FIGS. 9 and 10 , comprises in this embodiment a main body  31  and a pin  32  arranged at one end  33  of the locking means. The main body  31  has a circular cross section. The pin  32  projects from the main body  31 . The pin  32  is displaceable between a projecting position, as depicted in  FIG. 9 , and a retracted position, as depicted in  FIG. 10 , in which the pin  32  is arranged inside the main body  31 . The pin  32  is preferably resilient or spring-loaded and attempts to adopt its projecting position. The pin  32  is connected to a strap  6  which extends through the main body  31  and out through the other end of the locking means  30 . The strap  6  is intended to connect the person pushing to the locking means  30 . When the user pulls on the strap  6 , the person pushing pulls on the pin  32  at the same time, so that the pin  32  reaches its retracted position. The main body  31  is further provided with a circumferential recess  34  arranged at a distance from the pin  32 . 
         [0074]    The actuating means  10 ′ comprises a first part  21  and a second part  22 . The first part  21  is displaceable relative to the second part  22  between a first and a second position. More precisely, the first part  21  is rotatable relative to the second part  22  about a geometrical axis for displacement between the first and the second position. The actuating means  10 ′, in the first position of the first part  21 , actuates the brake arrangement  8  so that it is in a braking state. In the second position of the first part  21 , the actuating means  10 ′ actuates the brake arrangement  8  so that it is in a non-braking state. The first part  21  attempts to adopt the first position in the absence of external influence. For example, the actuating means  10 ′ can be spring-loaded so that the first part  21  attempts to adopt the first position. 
         [0075]    The first part  21  is further provided with a handle part  13 . The handle part  13  is so arranged as to facilitate rotation of the first part  21  from the first position to the second position. 
         [0076]    The first and the second part  21 ,  22  together define a groove  40 . The groove  40  has a T-shaped cross section. The groove  40  extends all the way round a first part P 1  of the circumference of the actuating means  10 ′ (see  FIG. 13 ). This groove is not present in a second part P 2  of the circumference of the actuating means  10 ′, said second part being separate from the first part. For example, the circumferential groove  40  can extend around one quarter of the circumference of the actuating means  10 ′, and the groove is not present on one quarter of the circumference of the actuating means  10 ′. The groove  40  is intended to receive one end  33  of the locking means  30 . The circumferential recess  34  in the locking means  30  is intended to be arranged in the outer part of the groove  40 , and the outer end  33  of the locking means  30  is intended to be arranged in the inner part of the groove  40 . The geometry of the groove  40  is complementary to the geometry of the locking means  30 , so that the locking means  30  is prevented from being pulled out of the groove  40  when the locking means  30  is fully inserted into the groove  40 . The groove  40  thus functions as a retaining device. 
         [0077]    Inside the part of the groove  40  which is defined by the first part  21 , a recess (not shown) is arranged in the first part  21  in an angular position corresponding to the second position. The shape of the recess is complementary to the shape of the pin  32 . For example, the recess may be in the form of a circular hole if the pin  32  has a circular cross section. The recess is intended to receive the pin  32  of the locking means  30  for locking the first part  21  in the first position. 
         [0078]    The first part  21  and the second part  22  can be made of plastic. The handle part  13  and the locking means  30  can also be made of plastic. 
         [0079]    The safety arrangement in accordance with this second embodiment will now be described with reference to  FIGS. 11-14 . In  FIG. 11 , to which reference is now made, the first part  21  of the actuating means  10 ′ is in its first position, in which the actuating means  10 ′ actuates the brake arrangement  8  so that it is in its braking state. 
         [0080]    In order to permit displacement of the baby carriage  2 , the person pushing moves the locking means  30  towards the actuating means  10 ′ and brings the locking means  30  into the groove  40  of the actuating means  10 ′. The pin  32 , which is arranged at one end  33  of the locking means  30 , will then be pressed into the main body  31  of the locking means  30 . The person pushing takes hold of the handle part  13  and rotates the first part  21  of the actuating means  10 ′ towards the second position. The person pushing must then overcome the force which causes the first part  21  to attempt to adopt the first position. 
         [0081]    Rotation of the first part  21 , in a clockwise direction in the depicted embodiment, relative to the second part  22  will cause the locking means  30  to be arranged in the groove  40  which is formed by the first and the second part  21 ,  22 . The engagement of the locking means  30  with the groove  40  is illustrated in  FIG. 12 . When the first part  21  has been rotated until the position of the locking means  30  corresponds to the position of the recess on the first part  21 , the spring-loaded pin  32  will engage with the recess. The engagement of the pin  32  with the recess prevents further rotation of the first part  21  and locks the first part  21  in the second position, in which the brake arrangement  8  is in its non-braking state. The person pushing can now move the baby carriage  2  without being required to take hold of the handle part  13  in order to release the brake arrangement  8 . This position is depicted in  FIG. 13 . 
         [0082]    In a situation, in which the person pushing loses control of the baby carriage  2  for some reason, for example by falling, the person pushing will actuate the locking means  30  with a predetermined force in a direction away from the actuating means  10 ′. A person pushing who falls, for example, will actuate the strap  6 , as a consequence of which the pin  32  of the locking means  30  will be pulled out of its engagement with the recess of the first part  21 . As a result, the pin  32  ceases its locking of the first part  21  in the second position. The first part  21  will thus attempt to adopt its first position. This is because the first part  21  is no longer being acted upon by any external force. 
         [0083]    However, the locking means  30  is still arranged in the groove  40  which is defined by the first and the second part  21 ,  22 , as depicted in  FIG. 13 . The groove  40  thus functions as a retaining means and maintains its engagement with the locking means  30  until the first part  21  reaches the first position, in which the brake arrangement  8  adopts its braking state. Only when the first part  21  has been rotated to its first position does the locking means  30  move freely from the groove and is thus released from the actuating means  10 ′. The ability of the locking means  30  to move freely from the groove  40  denotes that the locking means  30  reaches that part of the actuating means  10 ′ which is not provided with any groove. This position is depicted in  FIG. 14 . The person pushing is now released from the baby carriage  2 , and the brake arrangement  8  is in its braking state. 
         [0084]    The retaining means in the form of the groove  40  acts as extra security because the locking means  30  is not released from the groove  40  until the first part  21  has reached the first position, in which the brake arrangement  8  is in its braking state. In the event that the first part  21  does not reach its first position, the locking means  30  maintains its engagement with the groove  40 , and the locking means  3  is not released from the actuating means  10 ′. Thus, the person pushing is also not released from the baby carriage  2 , and the baby carriage  2  cannot run away out of control. 
         [0085]    When the person pushing then wishes to release the brake arrangement  8  again, the person pushing turns the actuating means  10 ′ once again to its second position and introduces the locking means  30  into the groove in accordance with what has previously been described above with reference to  FIGS. 11-13 . 
         [0086]    A further embodiment of the safety arrangement  1  will now be described with reference to  FIGS. 15 and 16 . Similarly to what has been described previously with reference to  FIG. 1 , a safety arrangement  1  is arranged on a chassis for a baby carriage  2  or the like. For example, the safety arrangement  1  can be arranged on a handle part of the baby carriage  2 . In the manner described above, the safety arrangement  1  is connected to a brake arrangement  8  in accordance with what has been described in conjunction with the first embodiment. 
         [0087]    In the third embodiment, the actuating means  10  is displaceable between the first position, in which the brake arrangement  8  is in a braking state, the second position, in which the brake arrangement  8  adopts its non-braking state, and a third position, in which said brake arrangement  8  or a further brake arrangement  8  adopts a braking state. The safety arrangement is of the type which has been described previously with reference to  FIGS. 1-7 , in consideration of which the description of the construction and function of the safety arrangement  1  is not repeated here. 
         [0088]      FIG. 15  depicts the second position of the first part  11 , in which the brake arrangement  8  adopts its non-braking state, corresponding to  FIG. 4 . The baby carriage  2  is able to move freely in this position. It may be desirable, however, to be able to brake the baby carriage a little in order to reduce the baby carriage speed. On downhill slopes, for example, it may be desirable to brake the baby carriage so that the speed of the baby carriage is reduced without the baby carriage being brought completely to a halt. 
         [0089]    In the third embodiment, the first part  11  is displaceable relative to the second part  12  also between the second position and a third position. More precisely, the first part  11  is rotatable relative to the second part  12  about a geometrical axis for displacement between the second and the third position. The user can rotate the first part  11  by rotation of the handle part  13 . In the third position, said brake arrangement, or a further brake arrangement associated with the third position, adopts a braking state. 
         [0090]    The first, second and third positions of the first part  11  are arranged one after the other in a continuous rotational movement. The first part  11  reaches the second position by means of a rotational movement from the first position and reaches the third position by means of a further rotational movement from the second position. The rotational movement takes place in a clockwise direction in the depicted embodiment. 
         [0091]    In the third position, the brake arrangement  8  adopts its braking state, in which brake elements are in engagement with at least one wheel. The third position can be constituted by an angular interval. Rotation of the first part  11  within this angular interval, which constitutes the third position, will cause the brake arrangement  8  to adopt its braking state. The brake arrangement  8  can provide a progressively increasing braking force on rotation of the first part  11  into the third position.  FIG. 16  depicts the third position of the first part  11 , in which the brake arrangement  8  adopts a braking state. 
         [0092]    The safety arrangement  1  in its third position accordingly functions as a conventional handbrake for braking the baby carriage, for example on downhill slopes. The safety arrangement  1  thus provides a plurality of functions, such as the safety functions described above, together with a handbrake for use while pushing the baby carriage. 
         [0093]    It will be appreciated that an arrangement which comprises an actuating means  10  without a locking means also constitutes an invention, as depicted in  FIG. 17 . The actuating means  10  is of the type described with reference to  FIGS. 15 and 16 . The actuating means  10  comprises a first part  11  and a second part  21 , the first part  11  being displaceable relative to the second part  21  between a first position, a second position and a third position. The actuating means  10  is arranged, in the first position of the first part  11 , to actuate a brake arrangement  8  in such a way that it is in a braking state, the actuating means, in the second position of the first part  11 , being arranged to actuate the brake arrangement  8  so that it is in a non-braking state. The actuating means is arranged, in the third position of the first part  11 , to actuate said brake arrangement  8  or a further brake arrangement in such a way that it is in a braking state. The first part  11  is arranged, in absence of external influence, to adopt the first position. The first part  11  is rotatable relative to the second part about a geometrical axis for displacement between the first, second and third positions. 
         [0094]    The first, second and third positions of the first part  11  are arranged one after the other in a continuous rotational movement. The first part  11  reaches the second position by means of a rotational movement from the first position and reaches the third position by means of a further rotational movement from the second position. The rotational movement takes place in a clockwise direction in the depicted embodiment. 
         [0095]    In the third position, the brake arrangement adopts its braking state, in which brake element is in engagement with at least one wheel. The third position can be constituted by an angular interval. Rotation of the first part  11  within this angular interval, which constitutes the third position, will cause the brake arrangement to adopt its braking state. The brake arrangement can provide a progressively increasing braking force on rotation of the first part  11  into the third position. 
         [0096]    The user rotates the first part by means of the handle part  13  which is arranged on the first part. The first part  11  of the actuating means is rotated to its second position, in which the brake arrangement adopts a non-braking state. After a certain rotational movement, the first part  11  reaches its second position, in which the brake arrangement adopts a non-braking state. Because the first part  11  is arranged, in the absence of external influence, to adopt the first position, the user must apply a certain force in order to maintain the first part  11  in the second position and thus to be able to move the carriage. The first part  11  is displaceable between the second and the third position. If the user continues to rotate the first part  11  to the third position of the first part, the brake arrangement will adopt its braking state. 
         [0097]    The arrangement is thus able to adopt the first position, in which the brake arrangement is in a braking state, the second position, in which the brake arrangement adopts its non-braking state, and the third position, in which said brake arrangement or a further brake arrangement adopts a braking state. 
         [0098]    The arrangement can be provided with a catch for locking the first part in the second position. The catch can be in the form of a key or a button for locking the first part in the second position. The key can be so arranged as to cease said locking of the first part in the second position by application of a predetermined level of force. 
         [0099]    A brake arrangement can achieve the braking action in both the first position and the third position of the safety arrangement as described with reference to  FIGS. 15 and 16  and of the arrangement as described with reference to  FIG. 17 . A common brake arrangement can comprise a disc brake which is capable of achieving the braking action in the first position and the continuous braking in the third position. 
         [0100]    Alternatively, a first brake arrangement can achieve the braking action in the first position, and a second brake arrangement can achieve the braking action in the third position of the safety arrangement as described with reference to  FIGS. 15 and 16  and of the arrangement as described with reference to  FIG. 17 . The first brake arrangement can comprise, for example, a first brake element on a first wheel of the baby carriage. The first brake element can be a pin which is pushed into the wheel. The second brake arrangement can comprise, for example, a second brake element on a second wheel. The second brake arrangement can comprise, for example, an arrangement with brake blocks such as a rim brake or the like. 
         [0101]    In  FIGS. 15 ,  16  and  17 , a wire  7  connects the brake arrangement to the actuating means. In the event that the safety arrangement comprises a first and second brake arrangement, the actuating means  10  can be connected to the first and second brake arrangement by means of one common wire  7 , two separate wires or one branched wire. The wire  7  can be spring-loaded. 
         [0102]    The locking means  3  in the embodiment in  FIGS. 15 and 16  is provided with a collar  35 . The collar  35  is arranged transversely relative the longitudinal extension of the locking means. When the locking means  3  is releasably attached to the actuating means  10  for locking the first part  11  in the second position, the collar  35  is arranged to bear against an outer area of the second part  12 . A person skilled in the art will appreciate that such a locking means can also be used in the safety arrangement described with reference to  FIGS. 1-7 . 
         [0103]    It will be appreciated that the embodiment of the safety arrangement  1  which is described with reference to  FIGS. 8-14  can also be provided with the third position described above for the provision of a brake intended for use while pushing the baby carriage along. 
         [0104]    The safety arrangement is described above in conjunction with a baby carriage. It will be appreciated that the safety arrangement according to the invention can also be used for other types of carriage, wheel chairs, rollator walking frames on wheels or the like. The safety arrangement can also be used for similar purposes on other types of vehicles and machines where it is desirable for the vehicle to be braked if the operator loses control of the vehicle. Examples of such arrangements include lawn mowers, snowmobiles, jet-skis, hand tools, processing machines, trains, boats, etc. 
         [0105]    In the embodiment described with reference to  FIGS. 8-14 , the second part  22  exhibits a portion where the second part  22  does not enclose the first part  21 . In an alternative embodiment, the second part  22  can also enclose the first part  21  in this area. In this case, the second part  22  has an opening, into which the locking means can be introduced for engagement with the actuating means and an opening for the handle part  13 . Similarly to previously described embodiments, the first part  21  and the second part  22  do not form a groove in this area. 
         [0106]    A plurality of modifications and variations are accordingly possible, for which reason the scope of the invention is thus defined exclusively by the accompanying claims. It will be appreciated, for example, that the first and the second part of the actuating means can have different relative positions, which can mean that the first part, which carries the handle part, radially encloses the second part.