Patent Publication Number: US-11027761-B2

Title: Foldable carriage

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. Nonprovisional application Ser. No. 16/591,081, filed Oct. 2, 2019, which is a continuation of U.S. Nonprovisional application Ser. No. 15/634,461, filed Jun. 27, 2017, issued as U.S. Pat. No. 10,435,045 on Oct. 8, 2019, which is a continuation of U.S. Nonprovisional application Ser. No. 14/529,387, filed Oct. 31, 2014, issued as U.S. Pat. No. 9,718,488 on Aug. 1, 2017, which claims the benefit of U.S. Provisional Application No. 61/898,498, filed Nov. 1, 2013, the disclosures of which are hereby incorporated by reference in their entireties. 
    
    
     FIELD 
     A carriage, such as a stroller, and a method for folding a carriage. The carriage has a foldable frame comprising a plurality of elongated frame components and a pivot lock and can be folded between a use position and a storage position. The pivot lock is adapted to retain the frame of the carriage in the use position. 
     BACKGROUND 
     Foldable carriages, such as foldable strollers, have been developed to permit a user to reduce the size of the carriage, permitting easy storage and transportation when the carriage is not in use. Usually a foldable carriage can be folded between a use position in which the carriage can be used for transporting an object, and a storage position, in which the carriage has a reduced size permitting the carriage to be stored in an easy manner. 
     To retain a foldable carriage in a use position, the foldable carriage has a pivot lock. The pivot lock retains the foldable carriage in the use position but as a precaution needs to be unlocked before the foldable carriage can be folded to the storage position. 
     The German utility model No. DE 20218 521 U1 disclose a pushchair having a pivot lock operated via a rotateable handle. The handle is arranged to two wires which run inside of the tubular frame of the pushchair. The wires are in turn connected to a lock flange which after being displaced permits the pushchair to be folded. It has shown however that wires are subjected to wear and run the risk of being damaged due to such wear. As the wires generally tend to run inside of the tubular frame it is difficult to discover such wear in advance. Another solution is disclosed in the Chinese patent disclosure, publication No. CN 2730360Y. The latter document discloses a stroller with a pivot lock comprises a rotatable handle which cooperates with two rods. The rods assist in locking the stroller in a use position. Both the above mentioned solutions require components that run inside of frame components, hence they are still rather complex solutions. 
     There is a need to provide simple yet sturdy solutions which are suitable on different kinds of carriages, preferably strollers. 
     SUMMARY 
     It is an object of the present invention to remove or reduce at least one of the drawbacks of the mentioned prior art, or to provide for a useful alternative. The object is at least partly met by a carriage comprising a frame. The frame is foldable between a use position and a storage position. An attachment point for a plurality of elongated frame components, a pivot lock arranged at said attachment point for locking the frame in the use position, a pivot axis about which the frame can be folded. The pivot lock is operable by rotating at least a portion of at least one of said elongated frame components, preferably by rotating one of the elongated frame components. 
     The present invention provides for a pivot lock for elongated components, and a carriage comprising a pivot lock for elongated frame components, which reduces the risk for a user acquiring injury due to pinching or crushing in the joint or between elongated frame components. It removes, or at least reduces, the need for additional mechanisms inside of the elongated frame components, which reduces weight, costs and complexity of the end product. 
     The frame can be provided with a first and a second attachment point for elongated frame components. The pivot axis can in such a case extend between the first and the second attachment points for elongated frame components. The frame can thus be configured so that the frame is folded at the first and the second attachment points. In this case the attachment points are joints. 
     According to an aspect, an elongated frame component connects said first and said second attachment points for elongated frame components. In this embodiment, the first and the second attachment points shares an elongated frame component which enables both the first and the second attachment points to be manipulated using the mentioned elongated frame component. Both the first and the second attachment point can thus be provided with a pivot lock, which assures that the frame can be retained in the use position. The elongated frame component is preferably a transverse elongated frame component. Transverse in the sense that is has a substantially perpendicular extension with respect to at least some of the other elongated frame components connected at the attachment point. 
     According to an aspect, the pivot lock is operable by rotating the transverse elongated frame component. The transverse elongated frame component can be operable to unlock the pivot lock so that the frame can be folded to the storage position. The transverse elongated frame component can be rotated about it longitudinal center line clock wise and/or counter clock wise. By using the transverse elongated frame component to unlock the pivot lock; one pivot lock can be operated or even two pivot locks can be operated simultaneously. Further, it provides for a rigid connection which is not depending on a mechanism arranged inside of the elongated frame component, as the elongated frame component itself is used to translate a rotational motion to a longitudinal motion with respect to the elongated frame component. 
     The carriage can comprise a first wheel side and the second wheel side. The first wheel side and the second wheel side are connected via the transverse elongated frame component. The transverse elongated frame component is thus substantially parallel, or parallel, with the wheel pivot axis of the frame. This permits the frame to be folded in a favourable position with respect to the wheel pivot axis. 
     According to an aspect, the carriage can comprise one or more pivot lock to lock the frame in a use position. The carriage can be provided with a first and a second pivot lock for example. Two pivot locks provides for a safe configuration. The first and the second pivot locks can be operable by an elongated frame component, preferably the transverse elongated frame component. This enables a simultaneous and rigid control of the pivot lock using relatively few components. 
     The pivot lock can be configured in different ways. The pivot lock can comprise a first and a second lock member, wherein the pivot lock comprises a first lock member and a translation member, the first lock member is adapted to engage and disengage an elongated frame component by a relative displacement of the first lock member. Specifically, if the first lock member is of a cogwheel type lock member, or if it is a cogwheel, the rotational motion of the transverse elongated frame component is translated via the translation member to displace the first lock member along a longitudinal center axis of the transverse elongated frame component. 
     The rotation of the at least a portion of at least one of the elongated frame components displaces the first lock member in direction along a longitudinal center axis of the transverse elongated frame component. The solution provides for a rigid configuration as a frame component is used to translate an imparted rotational motion by a user, to the displacement of the first lock member. 
     The transverse elongated frame component can be arranged in different ways to manipulate the first lock member. The transverse elongated frame component comprises a first and a second end, and the first end of the transverse elongated frame component can be cooperating with the first lock member. The cooperation can be directly or indirectly. A direct cooperation is a direct connection between the first end of the transverse elongated frame component and the first lock member. An indirect cooperation is an indirect connection with the first lock member e.g. via an intermediate member such a coupling member, translation member or similar. 
     According to an aspect, the transverse elongated frame component has a longitudinal center axis, and the displaceable lock member is displaced in a direction along the longitudinal center axis. 
     According to an aspect, the at least a portion of at least one of the elongated frame components can comprise a rotation lock. It is advantageous if the rotation of the elongated frame component is not actuated accidentally by a user. A rotation lock to the elongated frame component address this issue. The rotation lock is preferably arranged on the transverse elongated frame component, or at least associated with the transverse elongated frame component. The rotation lock is adapted to prevent the transverse elongated frame component from being accidentally rotated; hence the frame of the carriage can be configured with double lock mechanisms. 
     The rotation lock can comprise a handle, wherein the handle is operable to unlock the rotation lock and to rotate the transverse elongated frame component. This enables a user to unlock a two lock mechanisms using one grip and without changing grip between unlocking the first rotation lock and thereafter unlocking the pivot lock so that the frame can be folded to a storage position. 
     According to an aspect, the invention also relates to a method for folding a carriage to a storage position. The carriage comprises a frame which is foldable between a use position and a storage position, an attachment point for a plurality of elongated frame components. The frame further comprises a pivot lock arranged at the attachment point for locking the frame in the use position, and a pivot axis about which the frame can be folded. The method comprises the steps of unlocking the pivot lock by rotating a portion of at least one elongated frame component, so that the carriage is permitted to be folded to the storage position. 
     It is also within the boundaries of the present invention to provide a pivot lock for locking a first elongated component from pivoting with respect to a second elongated component about a pivot axis. The pivot lock is arranged in an attachment point for the first and the second elongated frame components and an additional third elongated component. The third elongated component has a longitudinal center axis. Wherein the pivot lock is operated by rotating the third elongated component about its longitudinal center axis and wherein the pivot axis and the longitudinal center axis are substantially parallel. The pivot lock is a sturdy lock with relatively few components. 
     The pivot axis and the longitudinal center axis are preferably aligned with each other. 
     According to an aspect, the third elongated component comprises an angled surface wherein by rotating the third elongated component about its longitudinal center axis, a lock member is displaced in a direction along the longitudinal center axis of the third elongated component. The lock member is disengaged from the first elongated component, permitting the first and the second elongated component to be pivoted with respect to each other. 
     According to an aspect, the invention relates to a carriage comprising a frame, the frame is foldable between a use position and a storage position. The frame comprises an attachment point for a plurality of frame components and a pivot lock for retaining the frame in the use position. The pivot lock is operated by rotating a portion of the frame of the carriage to unlock the pivot lock permitting the carriage to be folded to the storage position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Non-limiting embodiments of the present invention will be described with reference to the accompanying figures in which: 
         FIG. 1  shows the frame of a stroller arranged in a use position, the frame is foldable to a storage position; 
         FIG. 2 a    shows a cross section of a portion of the frame shown in  FIG. 1 , illustrating a first and a second pivot lock, and portions of elongated frame members connected to a first and a second attachment point, the pivot locks being in a locked position; 
         FIG. 2 b    shows a cross section of a portion of the frame shown in  FIG. 1 , illustrating a first and a second pivot lock, and portions of elongated frame members connected to a first and a second attachment point, the pivot locks being in an unlocked position; 
         FIG. 3  shows the cross section of the first pivot lock at the first attachment point in greater detail, the pivot lock, and the first lock member, is in a locked position, in which the carriage is prevented from being folded; and 
         FIG. 4  shows the cross section of the first pivot lock at the first attachment point in greater detail, the pivot lock, and the first lock member, is in an unlocked position, in which the carriage can be folded. 
         FIG. 5  shows an exploded view of a portion of the frame with the first attachment point. 
         FIG. 6  shows the first end of the transverse elongated frame component without the first and the second elongated frame components attached thereto. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a carriage  1 , in this case a stroller for a child. The carriage  1  comprises a frame  2 , in this case a load carrying frame, a handle  3 , and a child seat receiving site  4  adapted to receive an insert or a seat for a child. A first and a second rear wheel  5 ,  6  and a front wheel  7 . The illustrated stroller is a tri wheel stroller, although the present invention is not limited to tri wheel strollers but can be applied on any carriage such as four wheel strollers. The carriage  1  is foldable, or collapsible. The carriage  1  can be folded between a use position, shown in  FIG. 1 , and a storage position. In the use position, the carriage  1  can be used to transport a child while in the storage position; the carriage  1  can easily be tucked away for storage or for transport in the trunk of a car for example. 
     The frame  2  is formed by a plurality of elongated frame components  10 . The elongated frame components  10  are generally formed by extruded aluminum, but other materials are possible such as polymers, composites, wood, steel such as sheet steel, tubes formed by different materials, the like or combinations thereof. It is important however that the elongated frame components are selected so as to be able to safely carry the weight of load, especially in the cases of strollers. 
     As mentioned the carriage  1  is foldable. The carriage  1  comprises a pivot axis Pc about which the carriage  1  can be folded, or pivoted, between the use position and the storage position. The carriage  1  also comprises a pivot lock  20  to lock the carriage  1  in the use position. The carriage  1  further has a first wheel side  12  and a second wheel side  13  and a wheel pivot axis Pw extending there between. The wheel pivot axis Pw of course extends between a first and a second wheel. In the shown embodiment, the carriage  1  can be folded substantially parallel with the wheel pivot axis Pw. 
       FIG. 2 a    shows a cross section of a first and a second pivot lock  20 ,  20 ′ which are in the shown embodiment substantially identical in function and structural features. Hereafter only one of the pivot locks  20 ,  20 ′ will be described in greater detail.  FIG. 2 a    further shows a transverse elongated frame component  10 ′″ and a rotation lock which will be described in greater detail with reference to  FIG. 2 b   . A carriage  1  can be provided with one or two, or more such pivot locks dependent on how the carriage is intended to be folded. The shown carriage  1 , and the frame  2 , can be folded once about the pivot axis Pc and can thus be provided with either one or two pivot locks  20 . 
     The pivot lock  20  is operated using one of the elongated frame components  10  and more precisely by rotating at least one of the elongated frame components. The elongated frame component is rotated about its longitudinal center line L, and can be rotated a predetermined amount of angular degrees, preferably from 1-360°, more preferably from 10-270°, even more preferably from 20-180°, even more preferably from 20-90°. 
     As is noticeable, the carriage  1  comprises a first and a second attachment point  30 ,  40  for elongated frame components  10 ′,  10 ″,  10 ′″. The pivot axis Pc intersects with the first and the second attachment point  30 ,  40  and a transverse elongated frame component  10 ′″ extends between and connects the first and the second attachment points  30 ,  40 . In the shown embodiment, each attachment point  30 ,  40  have three elongated frame components  10 ′,  10 ″,  10 ′″ attached thereto. As is noticed, the first and the second attachment points  30 ,  40  shares the transverse elongated frame component  10 ′″. Except for the transverse elongated frame component  10 ′″, a first elongated frame component  10 ′ and a second elongated frame component  10 ″ is attached to the attachment points  30 ,  40 . 
     The pivot lock  20  is configured for locking a first elongated component, in this case an elongated frame component  10 ′, from pivoting with respect to a second elongated component, in this case a second elongated frame component  10 ″, about a pivot axis Pc. The pivot lock is arranged in an attachment point  30 ,  40  for the mentioned first and the second elongated components and an additional third elongated component, in this case the transverse elongated component  10 ′″. The third elongated component has a longitudinal center axis L. The pivot lock is operated by rotating the third elongated component about its longitudinal center axis L, wherein the pivot axis Pc and the longitudinal center axis L are substantially parallel, and preferably aligned with each other. 
     The attachment points  30 ,  40  are joints  30 ′,  40 ′ at which the load carrying frame  2  can be folded. Each of the attachment points  30 ,  40  comprises a pivot lock  20  which is operated using the transverse elongated frame component  10 ′″. Any elongated frame component  10 ′,  10 ″,  10 ′″ connected to the attachment point could however be used to operate the pivot lock  20  dependent on the configuration of the pivot lock  20 . An advantage of using a transverse elongated frame component extending between the first and the second attachment points  30 ,  40 , is that the pivot locks  20 ,  20 ′ can be simultaneously operated, e.g. unlocked. 
     The pivot lock  20  comprises a first lock member  21  which can be displaced via a translation member  22 . The first lock member  21  engages both the first elongated frame component  10 ′ and the second elongated frame component  10 ″ when being in a lock position. When the first lock member  21  is engaged, the first and the second elongated frame components  10 ′,  10 ″ are prevented from being pivoted with respect to each other i.e. the frame  2  cannot be folded to a storage position. When the first lock member  21  is displaced from engagement using the translation member  22 , the first and the second elongated frame components  10 ′,  10 ″ are permitted to be pivoted with respect to each other i.e. the frame  2  can be folded to a storage position. 
     The transverse elongated frame component  10 ′″ comprises a first and a second end  10   a ,  10   b . Each end  10   a ,  10   b  is associated with a first lock member  21 . The first lock member  21  is substantially disc shaped and can be displaced between a first and a second position. The first position is also referred to as the lock position. In the first position, the first lock member  21  fixates the first elongated frame component  10 ′ with respect to the second elongated frame component  10 ″ by engaging both the first and the second elongated frame components  10 ′,  10 ″ via the attachment point  30 . The first attachment point  30  is effectively prevented from functioning as a joint, i.e. the first elongated frame component  10 ′ cannot be pivoted with respect to the second elongated frame component  10 ″. When the first lock member  21  is in the second position (shown in  FIG. 4 ), the first attachment point  30  is effectively functioning as a joint, i.e. the first elongated frame component  10 ′ can be pivoted with respect to the second elongated frame component  10 ″. 
     The pivot lock  20  will be described in greater detail with reference to  FIGS. 3 and 4 . 
       FIG. 2 b    shows the cross section of  FIG. 2 a    but with the pivot locks  20 ,  20 ′ in an unlocked position, i.e. the lock member  21  displaced to the second position, i.e. the unlocked position.  FIG. 2 b    further shows the rotation lock comprising a handle  70  and a lock mechanism  71 . The handle  70  is biased using a spring  72  from left to right. When a user counteracts the spring  72  and pushes the handle  70  from right to left as indicated by the arrow in  FIG. 2 b   , a pin  74  is displaced permitting the transverse elongated frame component  10 ′″ to be rotated about its longitudinal center line L. Due to the configuration of the handle  70 , the transverse elongated frame component  10 ′″ can be rotated about its longitudinal center line L using the handle  70 . Hence the carriage  1  can be folded using a two step lock mechanism in which a user first unlocks a rotational lock by a sliding motion of the handle  70 , and then using the same handle, and with no need to change grip, the user unlocks the pivot lock by rotating the handle  70  and thus rotates the transverse elongated frame component  10 ′″. 
       FIG. 3  shows the first lock member  21  in the first position, i.e. a locked position. In  FIG. 3 , the first end  10   a  of the transverse elongated frame component  10 ′″ is arranged to a coupling member  50  having a central bore  51  and a rim  52  arranged around the bore  51 . The rim is engaged with the second lock member so that if the transverse elongated frame component  10 ′″ is rotated about its longitudinal axis L, the coupling member  50  and the translation member  22  rotates synchronously with it. The first lock member  21  is biased towards the translation member  22  using a biasing member, in the shown embodiment in the form of a helical spring  55 . The spring  55  braces against an interior surface of a housing  56  of the attachment point  30 . A screw  57  extends through the housing  56  and connects the first lock member  21  via a sleeve  58  about which the translation member  22  can rotate. The sleeve  58  further provides a shelf  58 ′ against which the translation member  22  can rest. 
     As can be noticed in  FIG. 3 , the housing  56  is formed by a first portion  56   a  of the attachment point  30  and a second portion  56   b  of the attachment point  30 , which each portions are connected to an elongated frame component. A slip surface  59  is arranged on both the first and second portions  56   a ,  56   b  of the attachment point  30 , and can be said to divide the housing  56  in two halves. The slip surfaces  59  of the housing  56  are flat and configured so that the first and the second portions  56   a ,  56   b  of the housing  56  can slip against each other during folding of the frame  2  between the use position and the storage position. The first elongated frame component  10 ′ is attached to first portion  56   a  of the attachment point  30 , and the second elongated frame component  10 ″ is attached to the second portion  56   b  of the attachment point  30 . The slip surfaces  59  of each portion  56   a ,  56   b  of the housing  56  together define a plane Ps which is substantially perpendicular with respect to the pivot axis Pc of the frame  2  and the longitudinal center line L of the transverse elongated frame component  10 ′″. 
     As can be seen, the first lock member  21  is intersecting the slip surfaces  59  of the housing  56  and the plane Ps when the first lock member is in the first position. The first lock member  21  is a cogwheel (shown in greater detail in  FIG. 5 ). The teeth of the first lock member  21  engages the interior surface of the housing  56  and in in the lock position as shown in  FIG. 3 , the first lock member  21  engages both the first portion  56   a  of the housing  56  and the second portion  56   b  housing  56 . The first lock member  21  extends across the slip surfaces  59  of the housing and thus prevents the first elongated frame component  10 ′ and the second elongated frame component  10 ″ from pivoting with respect to each other. As mentioned above, the first lock member  21  is a cogwheel having teeth which interacts with the interior surface of the housing  56 . The interior surface of the housing  56  has corresponding grooves, adapted to engage with the teeth of the first lock member  21 . It should be noted that the interior surface of the housing  56  can be provided with teeth and the first lock member  21  with grooves instead. 
     Instead of using a cogwheel, the first lock member  21  can have substantially any polygonal form providing locking surfaces. For example, the first lock member could be pentagonal, hexagonal, heptagonal or the like. 
       FIG. 4  shows the pivot lock of  FIG. 3  with the first lock member  21  in the second position, i.e. an unlocked position. As can be seen in  FIG. 4 , the translation member  22  comprises tooth shaped protrusions  60  which engage the first lock member  21 . The tooth shaped protrusions  60  extend in a direction corresponding to the longitudinal center line L of the transverse elongated frame component  10 ′″. Each protrusion  60  comprises an angled surface  61 , forming the tooth shaped protrusions  60 . 
     When the translation member  22  is rotated, as a consequence of the rotation of the transverse frame component  10 ′″, the angled surfaces  61  of the protrusion  60  slips on a surface of the first lock member  21 , preferably formed by grooves, and push the first lock member  21  in a direction away from the translation member  22  and the first end  10   a  of the transverse elongated frame component  10 ′″. At one point, the protrusions  60  of the translation member  22  has pushed the first lock member  21  past the plane Ps formed by the slip surfaces  59  of the housing  56 , so that the first lock member  21  disengages from the second portion  56   b  of the housing  56  and its corresponding grooves, permitting the first frame component  10 ′ to be pivoted with respect to the second frame component  10 ″. It should be noted that in an embodiment, the transverse elongated frame component  10 ′″ can be provided with angled surfaces just as the protrusions  60  of the translation member  22 , i.e. the translation member  22  can be integrally formed with the transverse elongated frame component  10 ′″. 
     In  FIG. 4 , the slip surfaces  59  of the housing  56  is arranged to the left of the first lock member  21 , i.e. the first lock member  21  is displaced from the slip surfaces  59  and the plane Ps which they define. The first lock member  21  is thus disengaged from the second elongated frame component  10 ″ permitting the first elongated frame component  10 ′ and the second elongated frame component  10 ″ to pivot with respect to each other. 
     Each elongated frame component  10 ′,  10 ″,  10 ′″ is formed by a hollow tubular component formed by extruded aluminum, while the attachment point  30 ,  40 , and the housing  56 , in this case the joints  30 ′,  40 ′ are formed by a plastic material such as polypropylene. 
       FIG. 5  shows an exploded view of a portion of the frame  2  comprising the first attachment point  30 .  FIG. 5  shows from left to right; the second attachment point  40 , the transverse elongated frame component  10 ′″, the slidable handle  70  and the lock mechanism  71  providing a rotation lock for the transverse elongated frame component  10 ′″, a protective sleeve  73  comprising a gripping surface, the coupling member  50 , a first portion  56   a  of the housing  56  comprising the slip surface  59 , the translation member  22 , the first lock member  21 , the spring  55 , the second portion  56   b  of the housing  56 , and the screw  57  connecting the first portion  56   a  of the housing  56  with the second portion  56   b  of the housing  56  and indirectly the transverse elongated frame component  10 ′″. In the inside of the first portion  56   a  of the housing  56  grooves can be seen which cooperate with the teeth of the first lock member  21 . Similar grooves are arranged on the inside of the second portion  56   b  of the housing  56 . 
       FIG. 6  shows the first end  10   a  of the transverse elongated frame component  10 ′″ in greater detail without the first and the second elongated frame components  10 ′,  10 ″ attached thereto.  FIG. 6  specifically show the translation member  22  and the protrusions  60  with their angled surfaces  61 , adapted to interact with grooves arranged in the first lock member  21 . It should be noted that the transverse elongated frame component  10 ′″ can be rotated counter clock wise or clock wise dependent on which side the angled surfaces  61  is arranged on the protrusions  60 . If the protrusions  60  comprises angled surfaces  61  on two sides, it may be possible that the transverse elongated frame component  10 ′″ can be rotated about its longitudinal center line L in both a clock wise and in a counter clock wise direction, as indicated with the arrows CW (clock wise) and CCW (counter clock wise). The important feature is that the rotational motion of the transverse elongated frame component  10 ′″ can be translated to a motion in a direction along the longitudinal center line L of the transverse elongated frame component  10 ′″ so that the first lock member  21  can be displaced. 
     It is possible that instead of rotating an elongated frame component  10 ′,  10 ″,  10 ′″ as described above, only a portion of the elongated frame component is rotated. For example, the elongated frame component  10 ′″ can be formed by a first and a second elongated frame component which are rotatably connected together using e.g. a swivel connection between the first and the second ends  10   a ,  10   b . The position of such swivel connection is illustrated in  FIG. 2  with the reference SC. 
     According to a second aspect, the present invention also relates to a method for folding a carriage, such as a stroller, to a storage position. The carriage comprises a frame foldable between a use position and a storage position. An attachment point for a plurality of elongated frame components, a pivot lock arranged at the attachment point for locking the frame in the use position, a pivot axis about which the frame can be folded. The method comprises the steps of;—unlocking the pivot lock by rotating at least a portion of at least one elongated frame component, so that the carriage is permitted to be folded to the storage position.