GB2537662A

GB2537662A - Leg adjuster

Info

Publication number: GB2537662A
Application number: GB1506866.1A
Authority: GB
Inventors: Hope Jamie; Humphries Todd
Original assignee: Preston Innovations Ltd
Current assignee: Preston Innovations Ltd
Priority date: 2015-04-22
Filing date: 2015-04-22
Publication date: 2016-10-26
Anticipated expiration: 2035-04-22
Also published as: GB2537662B; GB201506866D0

Abstract

A leg adjuster for a bar with first 11 and second 12 telescopic tubes comprising a sleeve like housing 10 arranged to be mounted over a joint between the tubes, a locking member 14 arranged to selectively restrict movement of one of the tubes, an actuation member 15 arranged to control the condition of the locking member and an externally positioned actuator to control the actuation member 15. The device may include an end stopper 23 and utilise a spring biased locking plate 14 with an aperture 22 shaped to engage a tube at an angle in a locked position using friction which can be straightened to release it through movement of a pin 15. The device is designed to be used on an item of furniture and in particular anglers tables, chairs and beds. The tubes may have square or circular cross sections.

Description

Leg Adjuster This invention relates to a telescopic leg adjuster, particularly, but not necessarily exclusively, for anglers' tables, chairs and beds.

Telescopic legs are common components of outdoor chairs and beds, such as those used by anglers, due to their ability to compensate for uneven ground and compact for travel and storage. Typically, telescopic leg components consist of one or more leg members that can slide relative to one another, adjusting the leg substantially vertically to any length between a minimum leg length (fully compressed state) and a maximum leg length (fully extended state).

For the sake of simplicity, further explanation shall refer to a leg composed of just two main members; the inner leg member and the outer leg member. In the fully compressed state, the inner leg member is enclosed within the outer leg member, whereas, in the fully extended state, the inner leg member is pulled out to the maximum length permitted.

The majority of adjustable legs used in anglers' accessories (such as chairs, beds and tables) operate via a standard design, utilising a spring loaded locking plate which is selectively movable between a locked configuration and a released configuration, in which the leg can be extended or retracted, as required, by sliding the inner leg member further into, or out of, the outer leg member. A bracket is mounted at the lower end of the outer leg member, such that it overlaps the joint between the outer and inner leg members, and an opening is provided on one side of the bracket to accommodate a spring biased locking plate, which extends through the gap and beyond the outer periphery of the adjacent bracket wall. The gap permits movement of the exposed edge of the locking plate between the above-mentioned locked and released configurations. An extension spring is affixed at the exposed edge of the locking plate, between the lower surface of the locking plate and the bracket, which acts to bias the exposed edge of the locking plate upwardly and secure it at an angle relative to the lateral axis of the leg. The plate has a generally central, substantially circular aperture through which the inner leg portion extends and, when the locking plate is in the above-mentioned angled configuration, the inner edge of the aperture is forced (by the spring bias against the exposed edge of the plate) against the outer surface of the inner leg member, thereby preventing movement of the inner leg member relative to the outer leg member, and holding the assembly in the above-mentioned locked configuration. An actuating pin is slidably mounted within the bracket and provided with a push button at its distal end. The proximal end thereof is located adjacent the upper surface of the exposed edge of the locking plate. If a downward force is applied to the push button, the actuating pin is caused to move longitudinally downward, thereby applying a downward force to the exposed edge of the locking plate to be moved downward such that the locking plate is effectively rotated into a substantially horizontal orientation, thereby removing the force from the outer surface of the inner leg member and allowing it to slide freely, in a longitudinal direction, within the central locking plate aperture and relative to the outer leg member. When the desired extension/contraction of the inner leg member has been achieved, release of the push button removes the force of the actuating pin from the upper face of the exposed edge of the locking plate, thereby releasing the spring and causing it to extend to its original configuration, pushing the exposed portion of the locking plate up and forcing the inner edge of the central aperture thereof against the outer surface of the inner leg member, to secure it once again at the desired extension.

Thus, existing telescopic leg adjusters have a gap on the front face of the bracket through which a portion of the locking plate is exposed, and that portion thereof extends beyond the can be hazardous, in outer periphery of the leg and/or bracket. However, when the push button is depressed and the exposed end of the locking plate is forced from the raised, locked configuration to the lower, released configuration (and vice versa) it can pose a potential pinch point between the metal locking plate and the bracket. The gap and the space around the exposed edge of the locking plate may also become filled, and potentially jammed, with debris, preventing the locking plate from depressing fully, and therefore, adversely affecting the overall performance of the adjuster. Furthermore, exposure of the spring to atmospheric elements such as water and air may cause the spring to rust or otherwise corrode or becoming damaged, thereby adversely affecting performance and durability.

Aspects of the present invention seek to address at least some of these issues, and, in accordance with one aspect of the present invention, there is provided a leg adjuster for an adjustable bar, said bar comprising a first substantially tubular member and a second substantially tubular member telescopically mounted for longitudinal, slidable movement within, and relative to, said first tubular member, said leg adjuster comprising a selectively releasable locking member configured to be mounted proximal said first and/or second tubular member so as to secure said first and second tubular members to prevent relative movement thereof and including a selectively actuatable release member for selectively releasing said first and/or second tubular member and permitting manual slidable relative adjustment thereof so as to selectively adjust the length of said bar, a sleeve-like housing configured to be affixed around the outer peripheral wall of the bar and over an overlapping joint between said first and second tubular members, said housing being configured to enclose said locking member and including an actuation member therein, wherein selective operation of said actuation member causes corresponding actuation of said release member, and an actuator provided externally of said housing and communicably coupled to said actuation member within said housing for selective operation thereof.

Whilst some exemplary embodiments of the present invention may still employ the above-described spring loaded locking plate mechanism to switch the adjustable leg between fixed and released configurations, some aspects of the invention provide a sliding front cover that protects, and fully encases, the spring loaded locking plate that is exposed on the standard design, without affecting the operability thereof. This sliding cover may run inside two vertical grooves along either side of the bracket and double up as, or incorporate, a push button to depress one edge of the spring loaded locking plate, allowing the inner leg member to slide freely within, and relative to the outer leg member, so as to adjust the length of the leg.

The tubular members described above may be of a substantially square cross-section or a substantially circular cross-section.

In an exemplary embodiment of the invention the leg adjuster may comprise an end stopper consisting of a neck portion located within an end of the second tubular member, and, a head portion located over said end of the second tubular member, wherein the head portion may have substantially the same shape, configuration and/or dimensions as the internal cross-section of the first tubular member.

According to another exemplary embodiment of the invention, the actuation member comprises an actuating pin, communicably coupled to the release member wherein, in use, downward movement of said actuation member causes operation of said release member. The actuation member may be slidably mounted in a longitudinal channel provided in said housing.

The release member may be a spring biased locking plate operable by downward movement of the actuating pin.

The leg adjuster may comprise a housing comprising a main body incorporating an opening within which at least a portion of the release member is housed, and including a channel for receiving the actuation member, and the housing may further comprise a cover slidably mounted on said main body, over said opening, and incorporating said actuation member, wherein downward movement of the cover relative to the main body causes corresponding actuation of said release member. The cover and said actuation member may be integrally moulded to form an actuator. A projecting ridge may be formed at an upper edge of said cover.

There may be provided an opening in said cover to accommodate an elongate stop member which extends from the outer surface of the main body into the channel and is configured to limit upward movement of the cover. Accordingly, the actuating pin may include an elongate, longitudinal cut-out portion into which said stop member extends, the cut-out portion having opposing end walls defining the limit of travel of said cover.

According to another aspect of the present invention, there is provided an item of furniture including at least one leg comprising a first substantially tubular member and a second substantially tubular member telescopically mounted for longitudinal, slidable movement within, and relative to, said first tubular member, and a leg adjuster substantially as described above mounted over an overlapping joint between said first and second tubular members.

Whilst the invention has been described above, it extends to any inventive combination of the features set out above, or in the following description. Other aspects of the present invention will be apparent to a person skilled in the art from the following specific description in which embodiments of the present invention are described, by way of examples only, and with reference to the accompanying drawings, in which: Figure 1 is a front view of a leg adjuster according to an exemplary embodiment of the invention; Figure 2 is a side cross-sectional view of a leg adjuster according to an exemplary embodiment of the invention when in a locked configuration; and Figure 3 is a side cross-sectional view of a leg adjuster according to an exemplary embodiment of the invention when in a released configuration.

Referring to Figures 1 to 3, the leg adjuster is maintained across the joint of a pair of telescopic leg members, 11 and 12. The main body 10 of the leg adjuster is mounted at the lower end of the outer leg member 11, such that it overlaps the joint between the outer leg member 11 and the inner leg member 12.

Referring to Figures 2 and 3, there is an opening provided on one side of the main body 10 of the leg adjuster within which a metal locking plate 14 is housed. The opening extends into the main body of the leg adjuster to form a tapered recess 13 therein. The locking plate 14 is a rigid metal locking plate with a generally central, substantially circular aperture 22 of roughly the same diameter as that of the inner leg member 12, through which the inner leg portion extends. It is the interaction between the inner leg member 12 and the locking plate aperture 22 that determines whether the leg adjuster is in the locked or released configuration. The locking plate 14 has a fixed edge 14b located at the narrow portion of the recess 13, that is maintained in a lowered position, and a free edge 14a located at the opposite, wider portion of the recess 13, permitting movement of the free edge between locked and released configurations.

As seen in Figures 2 and 3, an extension spring 18 is affixed to the free edge 14a of the locking plate 14, between the lower surface of the locking plate 14 and the main body 10 of the leg adjuster. This acts to bias the free edge 14a of the locking plate 14 upwardly and secure it at an angle relative to the lateral axis of the leg. When the locking plate 14 is in this angled configuration, the inner edge of the aperture 22 is forced (by the spring bias against the free edge 14a of the locking plate 14) against the outer surface of the inner leg member 12, acting as a friction locking device to prevent movement of the inner leg member 12 relative to the outer leg member 11, and holding the assembly in the locked configuration.

There is a longitudinal channel 20 inside the main body 10 of the leg adjuster. A moulded cover 17 is provided over the front face of the main body 10, covering the open portion of the recess 13. The cover 17 includes, on the inner surface thereof, an actuating pin 15 which is slidably mounted in the longitudinal channel 20. The cover 17 is further provided with an upper ridge 16 at its distal end, located externally above the main body 10 of the leg adjuster. The proximal end of the actuating pin 15 is located adjacent to the upper surface of the free edge 14a of the locking plate 14, within the main body 10.

Referring to Figures 2 and 3, the cover 17 may provide an opening 19 to accommodate an elongate stop member 24, such as a screw. The actuating pin 15 includes an elongate, longitudinal cut-out portion 21 into which said stop member 24 extends, the cut-out portion 21 having opposing end walls defining the limit of travel of the cover 17. The elongate stop member 24 extends from the outer surface of the main body 10 into the cut-out portion 21, preventing the end walls of the cut-out portion 21 from passing, thereby limiting the upward and downward movement of the cover 17. The upper limit prevents the cover 17 from detaching from the main body 10 of the leg adjuster. The front face of the main body 10 comprises a pair of longitudinal ridges on opposing edges, and the opposing side edges of the cover 17 cooperate with the respective ridges to define a sliding engagement therebetween.

As seen in Figure 3, if a downward force is applied to the upper ridge 16, the cover 17 and the actuating pin 15 are caused to move longitudinally downward, relative to the main body 10, such that the activating pin 15 pushes the free edge 14a of the locking plate 14 downwards and the locking plate 14 is effectively rotated into a substantially horizontal orientation, thereby compressing the spring 18, and relieving the friction between the locking plate aperture 22 and the inner leg member 12. This enables the inner leg member 12 to slide freely, in a longitudinal direction, within the central locking plate aperture and relative to the outer leg member 11, enabling the user to adjust the length of the leg.

As seen in Figure 2, release of the upper ridge 16 removes the force of the actuating pin from the upper face of the free edge 14a of the locking plate 14, thereby releasing the spring 18 and causing it to extend to its original configuration, elevating the free edge 14a of the locking plate 14. This pushes the free edge 14a of the locking plate 14 up, forcing the inner edge of the central aperture 22 against the outer surface of the inner leg member to secure it in the locked configuration at the desired extension. In addition, the actuating pin 15 is pushed upwardly by the locking plate 14 and the cover 17 thus springs back to its original confirmation.

Referring to Figures 2 and 3, there is provided an end stopper 23 comprising a neck 23a and a wider head 23b. The neck 23a of the end stopper is located in the upper end of the inner leg member 12. The head member 23b thereof is located adjacent to and externally of the upper edge of the inner leg member 12, and is roughly the same shape, configuration and/or dimensions as the internal cross-section of the outer leg member 11. This reduces or eliminates play between the inner leg member 12 and the outer leg member 11, resulting in a reduction of wobble and an increased stability of the leg.

It will be apparent to a person skilled in the art, from the foregoing description, that modifications and variations can be made to the described embodiments without departing from the scope of the invention as defined by the appended claims.

Claims

CLAIMS1. A leg adjuster for an adjustable bar, said bar comprising a first substantially tubular member and a second substantially tubular member telescopically mounted for longitudinal, slidable movement within, and relative to, said first tubular member, said leg adjuster comprising a selectively releasable locking member configured to be mounted proximal said first and/or second tubular member so as to secure said first and second tubular members to prevent relative movement thereof and including a selectively actuatable release member for selectively releasing said first and/or second tubular member and permitting manual slidable relative adjustment thereof so as to selectively adjust the length of said bar, a sleeve-like housing configured to be affixed around the outer peripheral wall of the bar and over an overlapping joint between said first and second tubular members, said housing being configured to enclose said locking member and including an actuation member therein, wherein selective operation of said actuation member causes corresponding actuation of said release member, and an actuator provided externally of said housing and communicably coupled to said actuation member within said housing for selective operation thereof.
2. A leg adjuster according to Claim 1, wherein said tubular members are of a substantially square cross-section.
3. A leg adjuster according to Claim 1, wherein said tubular members are of a substantially circular cross-section.
4. A leg adjuster according to any of the preceding Claims, wherein said leg adjuster further comprises an end stopper consisting of a neck portion located within an end of the second tubular member, and, a head portion located over said end of the second tubular member, the head portion having substantially the same shape, configuration and/or dimensions as the internal cross-section of the first tubular member.
5. A leg adjuster according to any of the preceding Claims, wherein the actuation member comprises an actuating pin, communicably coupled to the release member wherein, in use, downward movement of said actuation member causes operation of said release member.
6. A leg adjuster according to Claim 5, wherein the actuating pin is slidably mounted in a longitudinal channel provided in said housing.
7. A leg adjuster according to Claim 5 or Claim 6, wherein said release member is a spring biased locking plate operable by downward movement of the actuating pin.
8. A leg adjuster according to any of the preceding Claims, including a housing comprising a main body incorporating an opening within which at least a portion of the release member is housed, and including a channel for receiving the actuation member, the housing further comprising a cover slidably mounted on said main body, over said opening, and incorporating said actuation member, wherein downward movement of the cover relative to the main body causes corresponding actuation of said release member.
9. A leg adjuster according to Claim 8, wherein said cover and said actuation member are integrally moulded to form an actuator.
10. A leg adjuster according to Claim 8 or Claim 9, comprising a projecting ridge formed at an upper edge of said cover.
11. A leg adjuster according to any one of Claims 8 to 10, wherein said cover includes an opening to accommodate an elongate stop member which extends from the outer surface of the main body into the channel and is configured to limit upward movement of the cover.
12. A leg adjuster according to Claim 11, wherein the actuating pin includes an elongate, longitudinal cut-out portion into which said stop member extends, the cut-out portion having opposing end walls defining the limit of travel of said cover.
13. A leg adjuster substantially as herein described and/or with reference to the accompanying drawings.
14. An item of furniture comprising at least one leg including a first substantially tubular member and a second substantially tubular member telescopically mounted for longitudinal, slidable movement within, and relative to, said first tubular member, and a leg adjuster according to any of the preceding Claims mounted over an overlapping joint between said first and second tubular members.