Strap fastening device

A strap fastening device includes two fastening straps and a tightness adjusting unit. The fastening straps each have a fixing end and an opposing free end. The tightness adjusting unit includes an assembling box and two locating members. The assembling box is provided at a left and a right half with at least one non-return retaining tooth each. The two locating members are slidably mounted to the assembling box and connected to the free ends of the two fastening straps, such that the free ends of the fastening straps are not turned back to expose from the assembling box. The slidable locating members respectively have a raised locating rib releasably engaging with the at least one non-return retaining tooth at the left and the right half of the assembling box. The two locating members can be conveniently slid with one hand to adjust the tightness of the fastening straps.

FIELD OF THE INVENTION

The present invention relates to a strap fastening device, and more particularly to a strap fastening device that is configured for connecting to two opposite ends of an object and is adjustable to provide different levels of tightness thereof.

BACKGROUND OF THE INVENTION

A fastening strap is frequently connected to an object, such as a diving mask, a pair of swimming goggles, a fin, or a pair of snow goggles, for tightly holding the object to a wearer. Generally, the fastening strap is connected to and between two opposite ends of the object and is adjustable in tightness, allowing the object to be comfortably worn on the wearer's body area, such as the wearer's head or feet, to where the object is fitted.

Conventionally, the fastening strap is usually integrally formed using an elastic material, such as silicon rubber or rubber. Two opposite free ends of the fastening strap are movably extended through, for example, two buckles connected to two opposite ends of the object and turned back to be held to the buckles. By pulling the turn-back free ends of the fastening strap, the tightness of the object against the wearer's body area can be adjusted.

The above conventional fastening strap has the disadvantages of inconvenient to handle, uneven tightness, and tending to interfere with other nearby devices. Among others, Taiwan Patent Publication No. 239925 discloses an improved fastening strap, which includes a curved assembling plate, two straps, and two push plates. The curved assembling plate is provided on an outer surface near two opposite ends with two laterally symmetrical slots, and two opposite ends of the curved assembling plate are formed into two open entrances equipped with a shaft each. The curved assembling plate is provided at predetermined positions with retaining holes for engaging with retaining hooks provided on the push plates. The straps are made of an elastic material to thereby provide a certain degree of lengthwise elasticity. Each of the straps is provided with a plurality of non-return retaining teeth protruded from an outer surface of the strap. The non-return retaining teeth allow the straps under pressure to be pulled outward but stop the outward pulled straps from retracting reversely. The straps are movably connected at respective fixing ends to two opposite sides of a frame of an object. The free ends of the straps are separately extended through the two slots on the curved assembling plate to wind around the shaft each before being outward turned back to expose from an outer side of the assembling plate to form two turn-back sections. Meanwhile, the non-return retaining teeth on the straps passing the shafts are stuck at the shaft. The push plates are connected to the curved assembling plate through engagement of the retaining hooks on the push plates with the retaining holes on the curved assembling plate. The push plates are of an elastic structure, so that outer sections or operating sections of the push plates can be compressed inward and elastically extend outward, allowing the push plates to be elastically pulled. A raised non-return retaining rib having similar structure as the non-return retaining teeth on the straps is provided on an inner side of the operating section of each of the two push plates for controlling the tightening and the loosening of the turn-back sections. With these arrangements, the fastening strap disclosed in Taiwan Patent Publication No. 239925 can be more easily adjusted to different levels of tightness, compared to other conventional fastening straps.

However, the following disadvantages are found in the fastening strap disclosed in

Taiwan Patent Publication No. 239925:(1) The two turn-back sections are exposed from the curved assembling plate to result in an unpleasant appearance and tend to tangle with other objects to adversely affect the smooth installation and operation of other nearby devices; and(2) Particularly, the two turn-back sections are separately oriented to two opposite directions, and a user has to pull the two turn-back sections with two hands in two opposite directions in order to tighten the straps. That is, the two turn-back sections could not be handled with only one hand. Therefore, for a user, such as a diver, who usually holds some other device, such as a diving torch, with one hand, it would be inconvenient or even difficult to operate the turn-back sections with two hands to adjust the tightness of the straps.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a strap fastening device, with which it is not necessary to turn back the free ends of two fastening straps to expose the free ends from the strap fastening device.

Another object of the present invention is to provide a strap fastening device that can be easily and conveniently operated.

A further object of the present invention is to provide a strap fastening device that provides good applicability.

To achieve the above and other objects, the strap fastening device according to an embodiment of the present invention includes two elastic fastening straps and a tightness adjusting unit. The two elastic fastening straps each have a fixing end and an opposing free end. The fastening straps are pivotally connected at the fixing ends to two opposite lateral sides of the object. The tightness adjusting unit includes an assembling box and two slidable locating members. The assembling box is correspondingly provided on a left and a right half with at least one non-return retaining tooth each. The two locating members are separately slidably mounted on the assembling box and connected to the free ends of the two fastening straps. The two locating members each are provided at a predetermined position with a raised locating rib for releasably engaging with the non-return retaining teeth on the left and the right half of the assembling box. Therefore, by manipulating the two slidable locating members, the two fastening straps can be pulled, tensioned, and held in place related to the locating members. The free ends of the two fastening straps are located in the assembling box to separately connect to the two slidable locating members without being turned back to expose from the tightness adjusting unit. Thus, unlike the conventional strap fastening devices, the strap fastening device of the present invention has not exposed turn-back strap free ends to thereby avoid any interference with the smooth installation and operation of other nearby devices. That is, the fastening straps would not tangle with other nearby devices to cause any inconvenience. Furthermore, the two locating members can be conveniently slid with only one hand to adjust the tightness of the fastening straps.

According to an embodiment of the present invention, the assembling box includes a box body and a cover plate closed to each other. The box body is provided on a front face with two spaced and lengthwise extended elongated slots arranged side by side on a left and a right half of the box body, the non-return retaining teeth are separately located on an inner side of the front face above and below each of the two elongated slots, and the non-return retaining teeth located on the left and the right half of the box body are inclined in the same angle toward a central area between the left and the right half. Two opposite lateral ends of the box body are formed into two open entrances. The cover plate is closed onto a rear side of the box body opposite to the front face with the two elongated slots to thereby define a receiving space between the cover plate and the box body. The two slidable locating members respectively include a substantially U-shaped base plate and an operating plate. The U-shaped base plates provide a certain degree of elasticity and are received in the receiving space. The raised locating ribs are provided on an outer surface of the U-shaped base plates facing toward the non-return retaining teeth. The operating plates are separately perpendicularly extended from an end of the U-shaped base plates to outward project from the two elongated slots. And, the free ends of the two fastening straps are separately extended through the two open entrances of the box body into the receiving space to connect to the two slidable locating members.

According to an embodiment of the present invention, each of two the U-shaped base plates includes a rear plate portion and a front plate portion that are connected to each other and together define a sideward opened recess having an open end facing toward the central area of the box body and an opposing connected end, a notch is formed at the connected end to communicate with the sideward opened recess, and two plate-side mounting holes are formed at upper and lower ends of the connected end to separately locate above and below the notch. The operating plate is perpendicularly extended from the front plate portion at the open end of the U-shaped base plate, and the raised locating rib is formed on an outer surface of the front plate portion. The free end of each of the two fastening straps is formed into a post, in which an axially extended strap-side mounting hole is provided. By correspondingly disposing the posts at the free ends of the fastening straps in the sideward opened recesses via the notches and extending a pin through the plate-side mounting holes and the strap-side mounting hole on each of the U-shaped base plates, the two fastening straps are connected at the free ends to the two slidable locating members.

According to an embodiment of the present invention, the cover plate is provided with a plurality of retaining hooks and the box body is correspondingly provided with a plurality of retaining holes for engaging with the retaining hooks to thereby connect and close the cover plate to the box body.

According to an embodiment of the present invention, an elastic element is provided between the rear plate portion and the front plate portion of each of the slidable locating members to increase an elastic restoring force of the U-shaped base plates and ensure exact engagement of the locating ribs with the non-return retaining teeth.

According to an embodiment of the present invention, the elastic element is a spring that has sufficient elasticity to provide the U-shaped base plate with an elastic restoring force.

According to an embodiment of the present invention, the assembling box includes a first assembling box and a second assembling box arranged side by side, and a joining unit located between the first and the second assembling box to connect them to each other, such that the first and second assembling boxes can be turned about the joining unit to adjust an angle contained therebetween, allowing the assembling box to adapt to a configuration at the user's body area, to where the strap fastening device is fitted.

According to an embodiment of the present invention, the joining unit is a flexible soft pad provided on one surface of the cover plate facing away from the box body. The flexible soft pad connects the first assembling box and the second assembling box to each other and allows adjustment of an angle contained between the first and the second assembling box to ensure a comfortable contact of the first and second assembling boxes with the user's body area to where the strap fastening device is fitted.

According to an embodiment of the present invention, the joining unit includes a plurality of alternate lugs and recesses formed on two adjacent ends of the first and second assembling boxes and a first pivot shaft. The lugs on the first assembling box and the second assembling box are arranged in a staggered relation relative to one another. Each of the lugs being provided with a pivot hole, and the first pivot shaft is sequentially extended through the pivot holes on the lugs of the first and the second assembling box, such that the first and second assembling boxes can be connected together and turned about the first pivot shaft to adjust an angle contained therebetween.

According to an embodiment of the present invention, the joining unit includes a locking hook and a locking bar separately located at two adjacent inner ends of the first and second assembling boxes. The locking hook defines at an inner side thereof a locking space and is provided at a predetermined position with a notch, which communicates with the locking space. The locking bar includes a horizontally projected neck section and a retaining section perpendicularly connected to a distal end of the neck section; the retaining section is configured for rotatably fitting in the locking space with the neck section engaged with the notch, such that the first and second assembling boxes can be connected together and turned about the joint of the locking hook and the locking bar to adjust an angle contained therebetween.

According to an embodiment of the present invention, the joining unit includes a female fastener and a male fastener respectively located at two adjacent inner ends of the first and second assembling boxes. The female fastener is correspondingly provided on upper and lower sides thereof with a push element and a notch each, and the push element is located outside the notch; and the male fastener includes an upper and a lower lug, such that when the male fastener is inserted into the female fastener, the lugs are engaged with and outward projected from the notches. An angle contained between the first and the second assembling box can be adjusted at the joint of the female and the male fastener.

According to an embodiment of the present invention, the female fastener and the male fastener are pivotally turnably connected to the first assembling box and the second assembling box, respectively, via a second pivot shaft each, such that an angle contained between the first and the second assembling box can be adjusted at the joint of the female and the male fastener as well as at the second pivot shafts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described with some preferred embodiments thereof. For the purpose of easy to understand, elements that are the same in the preferred embodiments are denoted by the same reference numerals.

Please refer toFIGS. 1 to 5, in which a strap fastening device according to a first embodiment of the present invention is shown. The strap fastening device is connected to two opposite lateral ends of an object, such as a diving mask600as shown inFIG. 1or a fin700as shown inFIG. 5, and includes two fastening straps100and a tightness adjusting unit200.

The two fastening straps100are elastic fastening straps to provide a lengthwise elasticity. Each of the two fastening straps100has a fixing end110and an opposing free end120. The strap fastening device is pivotally connected at the fixing ends of the two fastening straps100to the two opposite lateral ends of an object, such as two opposite lateral ends of a diving mask600shown inFIG. 1or two opposite lateral sides at a rear end of a fin700as shown inFIG. 5.

The tightness adjusting unit200includes an assembling box300and two slidable locating members400. The assembling box300includes a box body310and a cover plate320.

The box body310is provided at a front face with two spaced and lengthwise extended elongated slots311, which are arranged side by side on a left and a right half of the box body. Two rows of continuously arranged non-return retaining teeth312are provided on an inner side of the front face separately along upper and lower edges of each of the two elongated slots311. The non-return retaining teeth312in the rows corresponding to the left and right elongated slots311are inclined in the same angle toward a central area between the left and the right half of the box body310. Two opposite lateral ends of the box body310each define an open entrance313.

The cover plate320is connected to the box body310from a rear side thereof, such that a receiving space314is defined between the cover plate320and the box body310. In practical implementation, the cover plate320and the box body310can be connected and closed to each other through engagement of a plurality of retaining hooks321provided on the cover plate320with a plurality of retaining holes315correspondingly provided on the box body310.

Each of the two slidable locating members400includes a base plate430and an operating plate410. The base plate430is bent into a substantially U-shaped configuration to provide a certain degree of elasticity. The U-shaped base plate430is disposed in the receiving space314defined between the box body310and the cover plate320, and includes a rear plate portion431and a front plate portion432that are connected to each other and together define a sideward opened recess433having an open end435facing toward the central area of the box body310and an opposing connected end434. Thus, the front plate portion432of the U-shaped base plate430can be elastically moved toward the rear plate portion431under an external force and automatically return to an original position away from the rear plate portion431when the external force is removed. The front plate portion432of the U-shaped base plate430is provided on an outer surface thereof with a raised locating rib420for releasably engaging with the non-return retaining teeth312above and below a corresponding one of the two elongated slots311. The operating plate410is perpendicularly extended outward from the front plate portion432at the open end435of the U-shaped base plate430, and is outward extended through a corresponding one of the two elongated slots311, such that a user can manipulate the operating plate410from outside of the assembling box300to slide the whole locating member400in the receiving space314of the assembling box300.

In practical implementation of the present invention, the rows of non-return retaining teeth312are not necessarily provided on the inner side of the box body310. For example, the rows of non-return retaining teeth312can be otherwise provided on an inner side of the cover plate320or other suitable positions. Similarly, the raised locating ribs420can be correspondingly provided on the slidable locating members400at positions facing toward the non-return retaining teeth312.

The free ends120of the two fastening straps100are separately extended into the receiving space314via the two open entrances313of the assembling box300to connect to the slidable locating members400. To connect the free ends120of the fastening straps100to the slidable locating members400, each of the two U-shaped base plates430is formed at the connected end434with a notch437communicating with the sideward opened recess433, and at upper and lower ends of the connected end434with two plate-side mounting holes436, which are separately located above and below the notch437; meanwhile, the free end120of each of the fastening straps100is formed into a post121, in which an axially extended strap-side mounting hole122is provided. By correspondingly disposing the free end120of each of the fastening straps100in the sideward opened recess433via the notch437and extending a pin440through the plate-side mounting holes436and the strap-side mounting hole122, the two fastening straps100are connected at the free ends120to the two slidable locating members400.

With the strap fastening device of the present invention, the free ends120of the two fastening straps100are located in the assembling box300to separately connect to the two slidable locating members400without being turned back to expose from the tightness adjusting unit200. Thus, unlike the conventional strap fastening devices, the strap fastening device of the present invention has an integral appearance without exposed turn-back strap free ends to thereby avoid any interference with the smooth installation and operation of other nearby devices. That is, the free ends120of the fastening straps100would not tangle with other nearby devices to cause any inconvenience.

Please particularly refer toFIG. 4. When the strap fastening device of the present invention has been fitted to a desired position on the user's body and the user wants to tighten the straps100, the user needs only to push the two operating plates410inward to release the raised locating ribs420from the non-return retaining teeth312in the assembling box300. At this point, the two operating plates410can be moved toward the central area of the box body310of the assembling box300while pulling the free ends120of the two fastening straps100further into the assembling box300, gradually bringing the fastening straps100into a tensioned state. When the fastening straps100have reached a desired tension to suitably tighten against the user's body, the two operating plates410can be released and the raised locating ribs420thereof would naturally engage with corresponding non-return retaining teeth312due to an elastic restoring force of the U-shaped base plates430. Similarly, when it is desired to loosen the two fastening straps100, the user needs only to push the two operating plates410inward to release the raised locating ribs420from the non-return retaining teeth312in the assembling box300. At this point, the two fastening straps100along with the two slidable locating members400are gradually pulled outward by a restoring force of the previously tensioned fastening straps100and become relaxed. When the fastening straps100have reached a desired relaxed state, the two operating plates410can be released and the raised locating ribs420thereof would naturally engage with corresponding non-return retaining teeth312to hold the slidable locating members400in place in the assembling box300due to the elastic restoring force of the U-shaped base plates430. To enable the above-described tightening/loosening and locating operations, the user needs only to inward push and release the two slidable locating members400with two fingers of one hand. Thus, the strap fastening device of the present invention is very easy and convenient to manipulate.

The non-return retaining teeth312are not necessarily limited to a certain fixed number. In the case there is only one non-return retaining tooth312provided above and below each of the two elongated slots311, the fastening straps100can be adjusted to only one different tightness. In the case there is a plurality of non-return retaining teeth312provided above and below each of the two elongated slots311, the fastening straps100can be accordingly adjusted to several different degrees of tightness.

FIG. 6is a sectional view of a strap fastening device according to a second embodiment of the present invention. The second embodiment is generally structurally similar to the first embodiment, except for an elastic element450, such as a spring, which is further provided between the rear plate portion431and the front plate portion432of each of the two U-shaped base plates430of the slidable locating members400, so as to increase the elastic restoring force of the U-shaped base plates430and ensure exact engagement of the raised locating ribs420with the non-return retaining teeth312.

FIG. 7is an assembled perspective view of a strap fastening device according to a third embodiment of the present invention, which is generally structurally similar to the previous two embodiments, except that the assembling box300is configured to be angularly adjustable to adapt to a configuration of the user's body area to where the strap fastening device is fitted. To do so, the assembling box300includes a first assembling box300aand a second assembling box300barranged side by side and connected to each other via a joining unit500located between them. With these arrangements, the assembling box300can be bent at the joining unit500, and an angle contained between the first and the second assembling box300a,300bcan be adjusted to adapt to the configuration of the user's body area, to which the strap fastening device is fitted.

The joining unit500can be in the form of, for example, a flexible soft pad, a pivot joint, a locking hook assembly, a side-release buckle, and so on. In the third embodiment illustrated inFIG. 7, the joining unit500is a flexible soft pad510attached to one surface of the cover plate320facing away from the box body310.

The flexible soft pad510connects the first assembling box300aand the second assembling box300bto each other and allows adjustment of an angle contained between the first and the second assembling box300a,300bto ensure a comfortable contact of the first and second assembling boxes with the user's body area.

FIG. 8is an exploded perspective view of a strap fastening device according to a fourth embodiment of the present invention, which is structurally similar to the third embodiment, except that the joining unit500thereof includes a plurality of alternate lugs520and recesses530formed on two adjacent ends of the two assembling boxes300a,300b.The lugs520formed on the first assembling box300aand on the second assembling box300bare arranged in a staggered relation relative to one another, so that the recesses530on the first assembling box300aand on the second assembling box300bare also arranged in a staggered relation relative to one another. Each of the lugs520is provided with a pivot hole521. By aligning the pivot holes521with one another and extending a first pivot shaft522through the aligned pivot holes521, the first and the second assembling boxes300a,300bare connected to each other and can be pivotally turned about the first pivot shaft522relative to each other to adjust an angle contained therebetween.

FIG. 9is an exploded perspective view of a strap fastening device according to a fifth embodiment of the present invention, which is structurally similar to the third embodiment, except that the joining unit500thereof includes a locking hook540and a locking bar550separately located at two adjacent inner ends of the first and second assembling boxes300a,300b.The locking hook540defines at an inner side thereof a locking space541, and is provided at a predetermined position with a notch542, which communicates with the locking space541. The locking bar550includes a horizontally projected neck section551and a retaining section552perpendicularly connected to a distal end of the neck section551. The retaining section552is configured for rotatably fitting in the locking space541with the neck section551engaged with the notch542. With these arrangements, the first and the second assembling boxes300a,300bare connected to each other via the joining unit500and can be pivotally turned relative to each other at a joint of the locking hook540and the locking bar550to adjust an angle contained therebetween.

FIG. 10is an exploded perspective view of a strap fastening device according to a sixth embodiment of the present invention, which is structurally similar to the third embodiment, except that the joining unit500thereof includes a female fastener560and a male fastener570separately located at two adjacent inner ends of the first and second assembling boxes300a,300b.The female fastener560is correspondingly provided on upper and lower sides thereof with a push element561and a notch562each, and the push element561is located outside the notch562; and the male fastener570includes an upper and a lower lug571. When the male fastener570is inserted into the female fastener560, the lugs571are engaged with and outward projected from the notches562. And, when the push elements561are pushed, the lugs571are released from the notches562to separate the first and the second assembling box300a,300bfrom each other. An angle contained between the first and the second assembling box300a,300bcan be adjusted at a joint of the female and the male fastener560,570.

FIG. 11is an exploded perspective view of a strap fastening device according to a seventh embodiment of the present invention, which is structurally similar to the sixth embodiment, except that the female fastener560and the male fastener570of the joining unit500are separately pivotally connected via a second pivot shaft572to two adjacent inner ends of the first assembling box300aand the second assembling box300b.Therefore, the first assembling box300aand the second assembling box300bcan be pivotally turned relative to each other at a joint of the female fastener560and the male fastener570as well as at the second pivot shafts572to thereby adjust an angle contained therebetween.

According to the present invention, each of the above-described fourth to seventh embodiments can be further provided on one surface of the cover plate320facing away from the box body310with the flexible soft pad510to enable a comfortable contact of the first and second assembling boxes300a,300bwith the user's body area.