FIELD AND BACKGROUND OF THE INVENTION

The invention relates to a footrest according to the introductory portion of claim 1 and to a footrest according to the introductory portion of claim 12.

Such a footrest is known from GB 2 275 183. The footrest has a footplate upon which the feet of the user can rest and foot operable means for unlocking and locking a height setting of the scissor structure supporting the footplate. A problem of such a footrest is that the crossing arms of the scissor structure can effectively operate as a scissor, in particular when the height of the footrest is lowered and thus causes a risk of injury to the user and in particular to feet and toes of the user. Also, operation of the operating member involves moving the operating member sideways against a spring biased return force, which is difficult to accomplish without leaning forward to see whether the operating member is operated as intended. While leaning forward a user is not in a normal sitting posture, so there is no direct feedback during adjustment of the height whether a current height setting is adequate and comfortable.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a height adjustable footrest with a height adjustable scissor structure which causes less risk of injury to a user, but which is of a simple construction and firmly supports a footplate at each selected height setting.

According to the invention, this object is achieved by providing a footrest according to claim 1.

Because the central hinge has at least a hinge body between the first and second arms, at least a first one of the first and second arms has at least a protrusion or recess, the protrusion or recess of the first one of the first and second arms engaging the hinge body so as to retain the hinge body positioned in longitudinal direction of the first one of the first and second arms, the hinge body has a recess or protrusion on a side facing away from the first one of the first and second arms, a recess or protrusion being provided on a side of the second one of the first and second arms facing the first one of the first and second arms, and the recess or protrusion of the hinge body is in hinging engagement with the protrusion or, respectively, recess provided on the side of the second one of the first and second arms facing the first one of the first and second arms, the first and second arm are maintained spaced from each other at the central hinge for reducing the risk of pinching of body parts of a user at the central hinge, while the hinge body also forms a bearing part of the central hinge, so that a simple construction is obtained which can be assembled efficiently.

It is another object of the invention to provide a height adjustable footrest of which the height adjustment can be operated more easily, yet is of simple construction.

According to the invention, this object is achieved by providing a footrest according to claim 12.

Because the operating member is guided for movement between an uppermost position projecting maximally from the footplate and a depressed position pressed-in towards the footplate relative to the uppermost position, it can easily be operated by foot.

Adjustability of the footrest is thereby achieved with a very simple construction, because the adjustment member and the anchoring member are arranged for mutual engagement if the adjustment member is in its upper position and for mutual disengagement allowing repositioning of the adjustment member relative to the anchoring member to another position for mutual engagement, if the adjustment member is in its lower position, and the operating member is arranged for urging the adjustment member from its upper position to its lower position if pressed-in towards its depressed position. In this construction, the only parts of the adjustment mechanism that are required to be movable are the adjustment member and the operating member. Also, the adjustment mechanism consists of a small number of parts.

Particular elaborations and embodiments of the invention are set forth in the dependent claims.

Further features, effects and details of the invention appear from the detailed description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of an example of a footrest according to the invention;

Fig. 2 is a side view of the footrest according to Fig. 1;

Fig. 3 is a perspective view from below of the footrest shown in Figs. 1 and 2;

Fig. 4 is an enlarged perspective view of a central hinge of a support structure of the footrest shown in Figs. 1-3;

Fig. 5 is a schematic cut-away view of the central hinge shown in Fig. 4;

Fig. 6 is a schematic cut-away view of a central hinge of a second example of a footrest according to the invention;

Fig. 7 is a further perspective view of the first example of a footrest according to the invention with a footplate pivoted away from a scissor structure of the footrest; and

Figs. 8 and 9 are further perspective views of a portion of the footrest in the position shown in Fig. 7.

DETAILED DESCRIPTION

In Figs. 1-5, a first example of a footrest according to the invention is shown. The footrest has a footplate 1 supported by a scissor structure 2. As shown in Figs. 7-9, the footplate 1 can be tilted relative to the scissor structure 2 about a tilting axis 66.

The scissor structure 2 has first arms 3 A, 3B and a second arm 4. The first and second arms 3A, 3B, 4 are hinged to each other at a central hinge 5 for mutual pivoting about a hinge axis 6 perpendicular to the first and second arms 3A, 3B, 4. In this example, the two first arms 3A, 3B form outer arms while the second arm 4 crosses the first arms 3A, 3B between the first arms 3A, 3B. However, other scissor structures with first and second arms are also conceivable, for instance a structure with single first and second arms or a structure with two first arms hinged to two second arms between the first arms or on the outside of the first arms. The first and second arms 3A, 3B, 4 are furthermore hinged to the footplate 1 at first end portions 7A, 7B, 8 of the first and second arms 3A, 3B, 4. The scissor structure 2 further has a base 9 to which the first and second arms 3A, 3B, 4 are hinged at second end portions 10A, 10B, 11 of the first and second arms 3 A, 3B, 4 opposite of the first end portions 7 A, 7B, 8 of the first and second arms 3A, 3B, 4.

The first end portion 8 of the second arm 4 is guided for movement along the footplate 1 towards and away from the first end portions 7 A, 7B of the first arms 3A, 3B and the second end portions 10A, 10B of the first arms 3A, 3B is guided for movement along the base 9 towards and away from the second end portion 11 of the second arm 4. In this example, the scissor structure 2 has movable hinge members 30A, 30B to which the first end 8 of the second arm 4 is articulated. The movable hinge members 30A, 30B are guided by and movable along upper guide rods 31 A, 3 IB mounted to cross beams 32, 33, to which the footplate 1 is mounted. For guiding the movable hinge members 34A, 34B to which the second ends 7 A, 7B of the second arm 4 are articulated, the base 9 has lower guide rods 35A, 35B mounted to cross beams 36, 37. Support feet 38 are mounted to lower outer ends of the cross beams 36, 37. At the second end portion 11, the second arm 4 is hinged relative to the base 9 for pivoting about a lower hinge axis 49 at a fixed position (not moveable along the lower guide rods 35A, 35B). To this end, lower fixed hinge members 51A, 51B are fixed to the guide rods 31A, 31B, in this example by means of locking pins. Other types of fixation, e.g. integral, locking or clamping, are conceivable as well.

Similarly, the first arms 3A, 3B are hinged relative to upper fixed hinge members 52A, 52B, and accordingly relative to the footplate 1, at the first end portions 7 A, 7B thereof about an upper hinge axis 50 in a fixed position. In this example, the upper fixed hinge members 52A, 52B are fixed against movement along the upper guide rods 31A, 31B by means of bolts. Other types of fixation, e.g. integral, locking or clamping, are conceivable as well.

Via the fixed hinge axes 49, 50, the footplate 1 is fixed relative to the base 9 against movement in longitudinal direction of the guide rods 31A, 3 IB, 35A, 35B. It is however also conceivable to provide that the hinge axes at the second end portion of the second arm or arms and at the first end portions of first arm or arms are also movable in longitudinal direction of the guides. This would allow lateral adjustability of the position of the footplate relative to the base in longitudinal direction of the guides within a range which increases with the height of the footplate above the base.

An adjustment member 12 of the scissor structure 2 holds the first (upper) end portions 7 A, 7B, 8 of the arms 3A, 3B, 4 at an adjustable distance. The adjustment member 12 is coupled to the first (upper) end portion 8 of the second arm 4, but may instead be mounted to the first (upper) end portion of one or both of the first arms or to the second (lower) end portion or portions of one or more of the arms. The adjustment member 12 is pivotably mounted to the first end portion 8 of the second arm 4 and pivotable vertically between an upper position and a lower position lower than the upper position.

An operating member 29 in the form of a knob projecting upwardly from a top side of the footplate 1 is coupled to the adjustment member 12 for disengaging the adjustment member 12 from one of the first end portions 7 A, 7B, 8 of the arms 3A, 3B, 4 and reengaging the adjustment member 12 with one of the first end portions 7 A, 7B, 8 of the arms 3A, 3B, 4 at a position associated with a selected height setting.

An anchoring member 57 is mounted in a fixed position relative to one of the upper hinge axes 50 about which the first arms 3A, 3B are pivotable relative to the footplate 1. In this example, this is achieved by providing the anchoring member 57 as a bridge fixed between the upper guide rods 31 A, 3 IB, so that the bridge is also in a fixed position relative to the fixed upper hinge axis 50. The adjustment member 12 and the anchoring member 57 are arranged for mutual engagement if the adjustment member 12 is in its upper position and for mutual disengagement allowing repositioning of the adjustment member 12 relative to the anchoring member 57 to another position for mutual engagement, if the adjustment member 12 is in its lower position. To this end, the adjustment member has a row of teeth 59 and the anchoring member 57 is provided with openings 61-65 each receiving one tooth of the row of teeth 59 if the adjustment member 12 is in its upper position.

By operating the knob 29, the adjustment member 12 is disengaged from one of the first end portions 7 A, 7B, 8 of the arms 3A, 3B, 4 so that the distance between the first end portions 7 A, 7B, 8 of the arms 3A, 3B, 4 can be reduced for increasing the height of the top surface of the footplate 1 of the footrest or increased for lowering the top surface of the footplate 1. Once the desired height has been reached, the knob 29 can be released. The adjustment member 12 is then biased back into engagement with the one of the first end portions 7 A, 7B, 8 of the arms 3A, 3B, 4 at a position associated with a selected height setting. The re-engagement of the adjustment member 12 with the one of the first end portions 7 A, 7B, 8 of the arms 3A, 3B, 4 may involve a slight vertical movement of the footplate 1 towards the nearest selectable height at which the adjustment member 12 can be in engagement with the one of the first end portions 7 A, 7B, 8 of the arms 3A, 3B, 4. The knob 29 is guided relative to the anchoring member 57 for movement between an uppermost position projecting maximally from the footplate 1 and a depressed position (not shown) pressed-in towards the footplate 1 relative to the uppermost position. This allows the knob to be operated by foot very easily.

The knob 29 is arranged for urging the adjustment member 12 from its upper position to its lower position if pressed-in towards its depressed position. Thus, only the knob 29 and the adjustment member 12 need to be movably suspended in the scissor structure 2, so that the adjustment mechanism can be of a very simple construction.

For a simple construction, it is furthermore advantageous that a spring 58 mounted to the anchoring member 57 is provided for urging the adjustment member 12 towards its upper position.

For allowing the knob 29 to hold the adjustment member 12 in its lower position as its position is readjusted and it moves along the upper guide rods 31 A, 3 IB, the adjustment member 12 has an upwardly facing contact surface 60 extending along the row of teeth 59 and a projection 68 of the knob 29 extending through a passage 69 in the anchoring member 57 contacts the upwardly facing contact surface 60. Thus, the adjustment member 12 can slide along a downwardly facing contact surface of the knob 29 keeping the teeth free from the openings 61-65 in the anchoring member 57 as the height of the scissor structure 2 is readjusted. For keeping the contact surface 60 aligned with the projection 68 of the knob 29, the adjustment member 12 is guided to limit sideways movement by guides 67 mounted to the anchoring member 57. In this example, these guides are provided in the form of pins 67.

When the height setting of the footrest approaches a minimal height, the arms 3A, 3B, 4 become oriented almost parallel to each other. Thus, the vertical space between the first and second arms 3A, 3B, 4 reduces to a spacing small enough to pinch off body parts of a user, such as toes or fingers of a user. To reduce the risk of body parts being pinched off, a substantial horizontal spacing in axial direction of the central hinge 5 is provided. This horizontal spacing is preferably at least 1.5 cm and at most 6 cm and more preferably the spacing is about 2.5 cm.

The central hinge 5 has hinge bodies 13 A, 13B between the first arms 3A, 3B and the second arm 4. The first arms 3A, 3B each have a protrusion 17 (see Fig. 5) engaging the respective hinge body 13A, 13B so as to retain the hinge body 13 A, 13B positioned in longitudinal direction of the respective first arm 3A, 3B, the hinge body 13A, 13B has a recess 15 (see Fig. 5) on a side facing away from the respective first arm 3A, 3B. A protrusion 18 (see Fig. 5) is provided on a side of the second arm 4 facing the first arm 3A, 3B. The recess 15 of each hinge body 13A, 13B is in hinging engagement with the protrusion 18 provided on the side of the second arm 4 facing the respective first arm 3 A, 3B.

Thus, such a spacing is provided in an efficient manner, while allowing a clean uncluttered design of the central hinge 5. This can also be achieved with a scissor structure having single first and second arms or having the second arms on the outside of one or more first arms. Furthermore, instead of protrusions co-operating with recesses, the inverse, i.e. recesses co-operating with protrusions can be provided. A recess or protrusions retaining the hinge body positioned in longitudinal direction of the respective first arm can also engage the hinge body from the outside instead of engaging a protrusion or recess of the hinge body.

The recess 15 of the hinge body 13 A, 13B is in the form of a passage. The protrusions 17, 18 of the first and second arms 3 A, 3B, 4 project into that recess 15 from opposite sides. Furthermore, the protrusion 18 provided on the side of the second arm 4 facing the first arm 3A, 3B is in hinging engagement with the recess 15 of the hinge body 13 A, 13B. Thus, both the protrusion 17 projecting from the first arm 3 A, 3B and the protrusion 18 projecting from the second arm 4 project into the same passage in the hinge body 13 A, 13B. Thus, the first and second arms are hinged relative to each other directly in a robust and simple manner, which allows to keep play very limited in a simple manner.

For obtaining a robust central hinge 5 and for keeping costs low, it is furthermore advantageous that the hinge body 13 A, 13B is integrally formed.

In the present example, the central hinge 5 further has, in addition to the first hinge bodies 13A, 13B, second hinge bodies 14A, 14B. The protrusions 18 of the second arm 4 each engage one of the second hinge bodies 14A, 14B so as to retain that second hinge body 14A, 14B positioned in longitudinal direction of the second arm 4. The second hinge bodies 14A, 14B in contact with the first hinge bodies 13A, 13B support the first hinge bodies 13A, 13B against tilting about the first arms 3A, 3B, while adding spacing between the first and second arms 3A, 3B and 4.

A passage 16 extends through the second hinge body 14A, 14B and the protrusion 18 on the side of the second arm 4 facing the first arm 3 A, 3B projects through the passage 16 extending through the second hinge body 14A, 14B. Thus, the protrusion 18 retains the second hinge body 14A, 14B in position in longitudinal direction of the second arm 4 and forms a hinge pin about which the first and second arms 3A, 3B and 4 are hinged relative to each other at the central hinge 5.

The hinge bodies 13 A, 13B, 14A, 14B have annular filler disc portions 23, 24 of a combined total thickness ti + t2 substantially filling up a spacing in the direction of the hinge axis 6 at which the first and second arms 3A, 3B and 4 cross each other. The disc portion 24 of the second hinge body 14A, 14B is of a thickness t2 while the protrusion 17 of the first arm 3 A, 3B projects towards the second arm 4 over a distance d. Because the distance d over which the protrusion 17 of the first arm 3 A, 3B projects towards the second arm 4 is smaller than or equal to the thickness t2 of the disc portion 24 of the second hinge body 14A, 14B, the first hinge body 13A, 13B has a thickness ti smaller than the remaining distance between the protrusion 17 and the second arm 4, so the first hinge body 13 A, 13B can first be mounted over the protrusion 18 on the side of the second arm 4 facing the first arm 3A, 3B, then the arms 3A, 3B, 4 can been hinged to bring the protrusions 17, 18 in generally coaxial positions, during which movement the first hinge body 13 A, 13B passes along the protrusion 17 in a direction perpendicular to the hinge axis 6, and subsequently, the first hinge body 13A, 13B can be moved in the direction of the hinge axis 6 to a position over the first protrusion 17.

The thickness ti of the disc portion 23 of the first hinge body 13A, 13B is larger than the thickness t2 of the disc portion 24 of the second hinge body 14A, 14B. Thus, a bearing surface of a large axial length in overlap with the protrusions 17, 18 of the first arm 3a, 3B and the second arm 4 is available for keeping the protrusions 17, 18 of the first arm 3a, 3B and the second arm 4 aligned.

The second hinge bodies 14A, 14B are each formed of two hinge body parts 25, 26 mounted to each other. All of these hinge body parts 25, 26 are identical, which reduces manufacturing costs. The hinge body parts 25, 26 have surface portions 27 bounding the passage 16 through that hinge body 14A, 14B from opposite sides for allowing the hinge body parts 25, 26 to be mounted around the protrusion 18 provided on the second arm 4 in a direction perpendicular to the hinge axis 6. Thus, the second hinge bodies 14A, 14B can be assembled around the protrusion 18 provided on the second arm 4 after the respective first hinge bodies 13 A, 13B have been shifted radially to a position coaxial with the protrusion 17 of the respective first arm 3 A, 3B and shifted axially over that protrusion 17. The hinge body parts 25, 26 are mounted to each other by means of bolts 39.

The first and second hinge bodies 13 A, 13B, 14A, 14B have circular outer circumferences 21, 22 coaxial with the hinge axis 6, so that the risk of body parts of the user or other objects are entrained around the hinge axis 6 during adjustment of the height of the footrest is very small.

For smooth hinging movement and for reducing wear, bearing bushes 55, 56 are mounted over the first and second protrusions 17, 18. The bearing bushes have cylindrical outer surface facing cylindrical inner surfaces of the first and second hinge bodies 13 A, 13B, 14A, 14B. This also allows the first and second protrusions 17, 18 to be of a non-cylindrical shape without adversely affecting smooth hinging movement and durability of the hinge 5. In this example, the first and second protrusions 17, 18 have rectangular crosssections which allows each of the first and second legs 3A, 3B, 4 including the first and second protrusions 17, 18 to be stamped of plate steel material as an integral part. The passages 15, 18 in the bushings 55, 56 are also of a non- cylindrical shape and fit around the first and second protrusions 17, 18 so as to prevent rotation of the bushings 55, 56 around the first and second protrusions 17, 18. Thus, wear of the bushings 55, 56 by movement relative to the first and second protrusions 17, 18 is substantially avoided. In this example, the passages 15, 18 in the bushings 55, 56 have a rectangular cross-section closely fitting to the first and second protrusions 17, 18. However, other shapes preventing rotation of the bushings about the protrusions can also be provided.

A spring 40 is encapsulated between each pair of the associated ones of the first hinge bodies 13 A, 13B and second hinge bodies 14A, 14B, in this example in an annular cavity in the respective first hinge body 13A, 13B. The first hinge bodies 13A, 13B are each fixed against rotation about the hinge axis 6 relative to the first arm 3 A, 3B by means of protrusions 41. The second hinge bodies 14A, 14B are each fixed against rotation about the hinge axis 6 relative to the second arm 4 by means of protrusions 44. The springs 40 are each coupled to the associated first hinge body 13 A, 13B and to the associated second hinge body 14A, 14B for biasing the first hinge body 13 A, 13B relative to the second hinge body 14A, 14B in a sense of rotation for increasing the height of the scissor structure 2. The torque exerted by the springs 40 contributes to lifting of the footplate 1 when the adjustment member 12 is uncoupled from the first and second arms 3A, 3B, 4. Because the springs 40 are encapsulated, the risk of injury to the user upon failure of one of the springs 40 or due to pinching between windings of the spring 40 or between the spring 40 and the first or second hinge body 13A, 13B, 14A, 14B is absent or very small. The encapsulated springs 40 are also shielded from dirt and dust, which reduces the risk of malfunctioning. The springs 40 can easily be mounted together with the second hinge bodies 14A, 14B while the scissor structure 2 is held in or near its highest height setting. In this example, the springs 40 are helical springs of which ends 45, 46 are anchored in bores 47, 48 in the hinge bodies 13A, 13B, 14A, 14B.

For urging the scissor structure 2 towards a position in which the footplate 1 is in its uppermost position, the scissor structure 2 further includes a tension spring 53 connected to an upper end 7B of one of the first arms 3B and to an upper end 8 of the second arm 4. The tension spring 53 pulls the upper end 7B of one of the first arms 3B and the upper end 8 of the second arm 4 towards each other, which also contributes to urging the footplate towards its upper position.

In axial direction of the hinge axis 6, the first arms 3A, 3B are on opposite sides, of the second arm 4 and mutually connected by bridge portions 42, 43 preventing the first arms 3A, 3B from moving apart in axial direction of the hinge axis 6. Thus, a shaft holding the first arms 3A, 3B together at the hinge axis 6 can be dispensed with, which allows a particularly clean design without axial projections beyond the outermost first arms 3 A, 3B at the hinge 5. In the present example, the bridge portions 42, 43 are integrally formed with the first arms 3A, 3B. However, the bridge portions may also be attached to the first arms or coupled to the first arms, for instance via the hinges at the ends of the first arms.

In Fig. 6, a central hinge 105 of a second example of a footrest according to the invention is shown. The scissor structure of this footrest has first arms 103 (of which only one is shown in Fig. 6) on opposite sides of a second arm 104. The arms are mutually hinged at the central hinge 105.

The central hinge 105 has hinge bodies 113 and the first arms 103 each have protrusions 117 engaging recesses 154 in the respective hinge body 113 so as to retain the hinge body 113 positioned in longitudinal direction of the respective first arm 103. The hinge bodies 113 each have a projection 115 on a side facing away from the first arm 103 with which it is in engagement. A recess 118 is provided on a side of the second arm 104 facing the first arm 103. The projection 115 of each hinge body 113 is in hinging engagement with the recess 118 provided on the side of the second arm 104 facing the respective first arm 103.

The central hinge 105 further has, in addition to the first hinge bodies 113, second hinge bodies 114 in which the recess 118 is provided. The recesses 118 on the second arm 104 each form a trunnion about which the first and second arms 103 and 104 are hinged relative to each other at the central hinge 105. The second arm 104 has projections 141 engaging recesses 116 in the second hinge bodies 114 for retaining the second hinge bodies 114 against displacement in axial direction of the second arm 104.

The second hinge bodies 114 are each formed of two hinge body parts 126 mounted to each other. The second hinge bodies 114 can be assembled around the protrusion 115 of the respective first hinge bodies 113. The hinge body parts 126 are mounted to each other by means of bolts 139.

The first hinge bodies 113 are fixed against rotation about the hinge axis 6 relative to the first arm 103 by means of protrusions 141. The second hinge bodies 114 are fixed against rotation about the hinge axis 6 relative to the second arm 104 by means of protrusions 144.