This invention relates to a device that allows for adjustment of the position of straps on a device. In particular, the invention relates to a device that allows the user to adjust the space between two straps on an article.
Straps on luggage and backpacks typically have set positions on the luggage or backpack, so that the distance between the straps is always fixed. This can make the backpack difficult to use for people whose bodies do not exactly fit the set width between the straps. This requires manufacturers to produce the items in several different sizes to fit different body types. It would be desirable to devise a system where the spacing between two straps on a device can be adjusted to account for users of different sizes.
It is therefore an object of the invention to provide a device for attaching a strap to an article, in which the lateral positioning of the strap on the article can be adjusted in a simple manner, so that the straps can be positioned wider or narrower relative to each other, depending on the size of the user. This object is accomplished by a strap adjustment device formed from a retaining body into which a strap connector is adjustably secured. The retaining body comprises a front wall, a rear wall, side walls, an interior cavity and a top opening extending in a horizontal direction. At least one of the front wall or rear wall contains at least one protrusion extending into the cavity. The strap connector comprises a strap connecting portion with at least one strap connecting element, and an adjustment portion disposed inside the cavity of the retaining body. The adjustment portion has at least one lower locking element and a distal end with a spring mounted on the distal end. The spring is preferably a coil spring. The spring is arranged so that the strap connector can be moved lower into the cavity by pressing on the strap connector against the force of the spring, toward the distal end. Releasing the downward pressure on the strap connector moves the strap connector back into a raised position, with the spring in a relaxed state. When the spring is in a relaxed state, the at least one protrusion on the retaining body prevents movement of the strap connector in the horizontal direction by blocking the at least one lower locking element from passing by the protrusion. Pressing the strap connector against the force of the spring moves the lower locking element below the protrusion, so that the strap connector can be moved in the horizontal direction to a new position within the retaining body, wherein the spring can then be released to position the strap connector in its new position.
Preferably, there are at least two protrusions disposed along a horizontal extent of the retaining body, such that the strap connector can be moved between three different positions in the cavity by pressing the strap connector to compress the spring and sliding the strap connector within the cavity, to clear the protrusions.
To lock the strap connector more securely in place, the strap connector can have two lower locking elements, with one of the lower locking elements being disposed on a side facing the front wall and another of the lower locking elements being disposed on a side facing the rear wall. The retaining body then has two protrusions on each of the front wall and rear wall for each of the horizontal locations, with the protrusions on the front wall facing the protrusions on the rear wall. In the preferred embodiment, there are thus four protrusions, with the two protrusions on the front wall facing the two protrusions on the rear wall.
In order to keep the strap connector from being pulled out of the retaining body when it is under tension from a strap, there is at least one lower locking ledge on the adjustment portion that interacts with the at least one lower locking element when the strap connector is pulled in a direction opposite the spring, to prevent the strap connector from being removed from the retaining body. The lower locking ledge extends across the entire width of the retaining body, so that it prevents inadvertent disengagement of the strap connector when the strap connector is in any of the positions along the retaining body. Preferably, there are two lower locking ledges that extend inward from each of the front and rear walls of the retaining body, and two lower locking elements on the strap connector. The protrusions on the retaining body extend downward from the lower locking ledges.
To add even more stability and strength under tension, the strap connector can have an upper locking element that interacts with at least one upper locking protrusion on the retaining body. Preferably, the upper locking element is an indentation in the adjustment portion, and the at least one upper locking protrusion seats in the indentation and further prevents removal of the strap connector from the retaining body when the strap connector is pulled in the direction opposite the spring. The two levels of locking from the lower locking elements and lower locking ledge, as well as from the upper locking protrusion and upper locking element make the device according to the invention able to withstand large amounts of tension, and prevents the strap connector from being pulled out of the retaining body, even when the tension is applied at various different angles. In fact, the greater the tension from a strap, the tighter the upper locking protrusion is pressed into the indentation in the strap connector, which then creates and even more secure connection.
The spring tension also keeps the strap connector securely connected to the retaining body because in the relaxed state, the spring presses the upper locking elements against the upper locking protrusions, and presses the lower locking elements against the lower locking ledges, to prevent movement of the strap connector within the retaining body. This also prevents any horizontal movement of the strap connector during use due to the friction between the parts.
Preferably, there is a cap covering the spring. The cap slides along the adjustment portion during compression and release of the spring.
The strap connecting element can take any suitable form. For example, the strap connecting element could be formed from a single bar separated from the rest of the strap connector by a slot, it could be formed by multiple bars and slots, or could form a D-ring. Other types of strap connecting devices could also be used.
The retaining body is configured to be permanently attached to a strap or article. In one embodiment, the rear wall of the retaining body extends beyond the perimeter of the front wall and is formed of a sewable material, so that it can be sewn directly to a strap or fabric article. In another embodiment, the rear wall has at least one slot for attachment of webbing, that can be sewn into a closed loop or closed by another buckle.
In order to have a simple assembly of the strap adjustment device, the front wall and side walls of the retaining body can be formed from a single piece unitary housing part that is snapped onto the rear wall after insertion of the strap connector. This way, the device can be disassembled by snapping off the front wall from the rear wall, yet after assembly keeps the strap connector securely within the retaining body. In another embodiment, the front and rear walls can be formed of a single piece, with a bottom cover that can be snapped on and off to allow for insertion of the strap connector.
The invention also relates to an article having two of the strap adjustment devices described above. The strap adjustment devices are arranged on the article in such a manner that a spacing of the strap connectors relative to each other, and thus the straps to which they are connected, is adjustable by moving the strap connectors in the horizontal direction within the retaining bodies. The article can be any suitable article, such as a backpack, infant carrier, luggage or other item that requires carrying.
Other objects and features of the present invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention.
In the drawings, wherein similar reference characters denote similar elements throughout the several views:
Referring now in detail to the drawings,
The assembled strap adjustment device 1 is shown in
As can be seen in the cross-sectional view in
The horizontal adjustment of strap adjustment device 1 is shown in
Alternative embodiments of the strap adjustment device are shown in
The present invention provides a simple, effective and reliable device that allows for the connection of two straps or other articles together, while providing a unique horizontal adjustability to accommodate users of all sizes.
Accordingly, while only a few embodiments of the present invention have been shown and described, it is obvious that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.