Patent Description:
In daily life, cords, such as a lace or a thread, are usually used to tighten articles. The most common tightening method is to use the cord to reciprocately pass through holes on the article, e.g., eyelets of a shoe, and then tie a knot to secure the article. But in this kind of tightening method, the knot is loosened easily owing to an external force. Not only does the knot need to be tied again, but also lots of inconveniences come owing to the insecurity of the articles.

In order to solve such problems, some practitioners developed a simple fastening mechanism including a case, an engaging unit and a spring. The case includes holes configured for the lace to pass therethrough. Through the reaction force between the spring and the engaging unit, the lace can be clamped between the engaging unit and the case so as to be fastened. The length of the lace can be changed by pressing the spring to change the position of the engaging unit. However, in such fastening mechanism, the restoring force of the spring is served as the securing force; thus, the lace is easily to be released owing to vibrations or an external force. In addition, the fastening mechanism has no space for receiving the lace, and the exposure of the lace may bring danger.

Therefore, some practitioners developed another kind of buckle which can be rotated to tighten the lace, and the lace can be received inside the buckle. Through the interference between components inside the buckle, the length of the lace as well as the tightness can be adjusted. However, the structure of the buckle is complex; as a result, the manufacturing cost is increased, and the buckle has assembly and repair difficulty. <CIT> discloses a fastening device including a case, a knob, a locking unit and a spool. The case includes a central shaft inserting into the case to combine with a bolt. <CIT> discloses a reel assembly including a spool housing, a knob and a spool. The spool includes pawls selectively engaged with the pawl teeth of the spool housing. <CIT> discloses an apparatus for tightening and loosening a lace including a base, a lace tightening and loosening member, a releasing unit and an interlocking member. A temporary sliding portion is disposed between a first positioning portion and a second positioning portion. <CIT> discloses a fixture including a main body and a fastening unit, and the fastening unit includes a tension member and an adjusting member.

Based on the above-mentioned problems, how to simplify the structure of the fastening device, reduce the manufacturing cost and maintain the securing capability becomes a pursuit target for practitioners.

According to the appended claim <NUM> of the present disclosure, a fastening device includes a case unit, a knob and an engaging unit. The case unit includes a wall forming a receiving space and a plurality of mounting teeth located at the wall and facing toward the receiving space. The knob covers on the case unit. The engaging unit is within the receiving space. The engaging unit corresponds to the mounting teeth and is selectively coupled to the knob. The knob is switched between a first position and a second position along an axial direction. When the knob is in the first position to couple to the engaging unit, the engaging unit is linked up with the knob and the engaging unit is engaged with one of the mounting teeth to prohibit the knob from rotating in a first direction, and when the knob is in the second position to disengage from the engaging unit, the engaging unit is remained in an original position and does not prohibit the knob from rotating in the first direction.

In one example, the fastening device further includes a spool and a positioning shaft. The spool is within the receiving space and includes a flexible clamping portion. The positioning shaft inserts into the spool and is coupled with the flexible clamping portion. The positioning shaft has the axial direction and is linked up with the knob. When the knob is in the first position, the knob is coupled to the spool.

In one example, the spool includes a hollow body, an upper ring portion and a lower ring portion. The hollow body includes an inner surface forming a hollow space, and the hollow space is configured for the positioning shaft to insert therein. The upper ring portion protrudes outward from one of two ends of the hollow body, and the lower ring portion protrudes outward from the other one of the two ends of the hollow body. The winding track is formed between the upper ring portion and the lower ring portion, and the flexible clamping portion protrudes from the inner surface toward the hollow space to couple to the positioning shaft.

In one example, the positioning shaft includes a positioning protrusion. When the knob is in the first position, the positioning protrusion is located at one of two sides of the flexible clamping portion, and when the knob is switched from the first position to the second position along the axial direction, the flexible clamping portion is displaced by the positioning protrusion such that the positioning protrusion is switched to the other one of the two sides of the flexible clamping portion.

In one example, the case unit further includes a partition protruding radially from the wall to separate the receiving space into an upper chamber and a lower chamber, and the engaging unit is located at the upper chamber.

In one example, the case unit further includes a limiting portion located at the upper chamber and connected to the partition, and the limiting portion is configured to limit the engaging unit.

In one example, the case unit further includes a through hole located at the partition. The limiting portion includes four limiting arms spaced apart circumferentially around the through hole, and a free end of each of the limiting arms is configured to limit the engaging unit.

In one example, the knob includes a plurality of first driving teeth, and the engaging unit includes a plurality of first combining teeth. When the knob is in the first position, the first driving teeth are engaged with the first combining teeth, and when the knob is in the second position, the first driving teeth are disengaged from the first combining teeth.

In one example, the knob further includes a cap body covering on the case unit, a post disposed at the cap body and protruding into the through hole, and a plurality of second driving teeth located at a distal end of the post to couple to the spool.

In one example, the knob further includes a cap body covering on the case unit, a post disposed at the cap body and protruding into the through hole, and a plurality of second driving teeth located at a distal end of the post. The fastening device further includes a gear assembly. The gear assembly includes a sun gear engaged with the second driving teeth, and a plurality of planetary gears spaced away from each other. Each of the planetary gears is engaged with the sun gear. The case unit further includes a plurality of inner teeth located at the lower chamber and engaged with the planetary gears.

The disclosure can be more fully understood by reading the following detailed description of the embodiments, with reference made to the accompanying drawings as follows:.

It will be understood that when an element (or mechanism or module) is referred to as be "disposed on", "connected to" or "coupled to" another element, it can be directly disposed on, connected or coupled to the other one element, or it can be indirectly disposed on, connected or coupled to the other one element, that is, intervening elements may be present. In contrast, when an element is referred to as be "directly disposed on," "directly connected to" or "directly coupled to" another element, there are no intervening elements present.

In addition, the terms first, second, third, etc. is used herein to describe various elements or components, these elements or components should not be limited by these terms. Consequently, a first element or component discussed below could be termed a second element or component.

<FIG> shows a three dimensional schematic view of a fastening device <NUM> according to one embodiment of the present disclosure. <FIG> shows one exploded view of the fastening device <NUM> of <FIG>. <FIG> shows another exploded view of the fastening device <NUM> of <FIG>. <FIG> shows one cross-sectional view of the fastening device <NUM> of <FIG>. <FIG> shows another cross-sectional view of the fastening device <NUM> of <FIG>. As shown in <FIG>, the fastening device <NUM> includes a case unit <NUM>, a knob <NUM> and an engaging unit <NUM>.

The case unit <NUM> includes a wall <NUM> forming a receiving space (not labeled) and a plurality of mounting teeth <NUM> located at the wall <NUM> and facing toward the receiving space. The knob <NUM> covers on the case unit <NUM>. The engaging unit <NUM> is within the receiving space. The engaging unit <NUM> corresponds to the mounting teeth <NUM> and is selectively coupled to the knob <NUM>. The knob <NUM> is switched between a first position and a second position along an axial direction I1. When the knob <NUM> is in the first position to couple to the engaging unit <NUM>, the engaging unit <NUM> is linked up with the knob <NUM> and the engaging unit <NUM> is engaged with one of the mounting teeth <NUM> to prohibit the knob <NUM> from rotating in a first direction R1, and when the knob <NUM> is in the second position to disengage from the engaging unit <NUM>, the engaging unit <NUM> does not prohibit the knob <NUM> from rotating in the first direction R1.

Hence, since the knob <NUM> is the only one which moves along the axial direction I1, and the engaging unit <NUM> is remained in the original position, the structure reliability is increased. The details of the fastening device <NUM> will be described in the following paragraphs.

The case unit <NUM> can include the wall <NUM>, a partition <NUM> and the plurality of mounting teeth <NUM>. The partition <NUM> protrudes radially from the wall <NUM> to separate the receiving space into an upper chamber S11 and a lower chamber S12. The engaging unit <NUM> is located at the upper chamber S11. To be more specific, the case unit <NUM> can further include a base <NUM>, and the wall <NUM> can include an upper wall portion <NUM> and a lower wall portion <NUM>. The lower wall portion <NUM> is affixed to the base <NUM>, and the partition <NUM> is connected to a lower end of the upper wall portion <NUM>. The wall <NUM> can further include four positioning portions <NUM> and four positioning holes <NUM>. Each of the positioning portions <NUM> protrudes downward from the lower end of the upper wall portion <NUM>. Each of the positioning holes <NUM> is located at the lower wall portion <NUM>, and is configured to receive the positioning portion <NUM>. After the positioning portions <NUM> are engaged with the positioning holes <NUM>, the lower chamber S12 is formed by the base <NUM>, the lower wall portion <NUM> and the partition <NUM>, and the upper chamber S11 is formed by the upper wall portion <NUM> and the partition <NUM>.

The case unit <NUM> can further include a limiting portion <NUM>. The limiting portion <NUM> is located at the upper chamber S11 and connected to the partition <NUM>. The limiting potion <NUM> limits the engaging unit <NUM>. Through the configuration of the limiting portion <NUM>, the engaging unit <NUM> can be limited in the upper chamber S11 and is prohibited from separating from the case unit <NUM>. Preferably, the case unit <NUM> can include a through hole <NUM> located at the partition <NUM>. The limiting portion <NUM> includes four limiting arms <NUM> spaced apart circumferentially around the through hole <NUM>. Each of the limiting arms <NUM> has a free end <NUM> configured to limit the engaging unit <NUM>. The through hole <NUM> penetrating a center of the partition <NUM> along the axial direction I1 allows the lower chamber S12 to communicate with the upper chamber S11. The four limiting arms <NUM> protrude upward from a part of the partition <NUM>, which is near the through hole <NUM>, and form the free ends <NUM> of lipped structure. Therefore, the engaging unit <NUM> can be put downward into the upper chamber S11 along the axial direction I1, and the four limiting arms <NUM> will be displaced so as to pass through a central hole (not labeled) of the engaging unit <NUM>. After the engaging unit <NUM> is put into the upper chamber S11, the four limiting arms <NUM> are restored and the free ends <NUM> limit the engaging unit <NUM> such that the engaging unit <NUM> is limited in the upper chamber S11.

The fastening device <NUM> can further include a spool <NUM> and a positioning shaft <NUM>. The spool <NUM> is within the receiving space and includes a flexible clamping portion <NUM>. The positioning shaft <NUM> is inserted into the spool <NUM> to couple to the flexible clamping portion <NUM>. The positioning shaft <NUM> has the axial direction I1 and is linked up with the knob <NUM>. When the knob <NUM> is in the first position to couple to the engaging unit <NUM>, the engaging unit <NUM> is engaged with one of the mounting teeth <NUM> to prohibit the spool <NUM> from rotating in the first direction R1, and when the knob <NUM> is in the second position to disengage from the engaging unit <NUM>, the engaging unit <NUM> does not prohibit the spool <NUM> from rotating in the first direction R1.

The spool <NUM> can include a hollow body <NUM>, an upper ring portion <NUM> and a lower ring portion <NUM>. The hollow body <NUM> includes an inner surface <NUM> forming a hollow space T2 configured for the positioning shaft <NUM> to inert therein. The upper ring portion <NUM> protrudes outward from one of two ends of the hollow body <NUM>. The lower ring portion <NUM> protrudes outward from the other one of the two ends of the hollow body <NUM>. A winding track T1 is formed between the upper ring portion <NUM> and the lower ring portion <NUM>, and the flexible clamping portion <NUM> protrudes from the inner surface <NUM> toward the hollow space T2 to couple to the positioning shaft <NUM>. In addition, the positioning shaft <NUM> can include a positioning protrusion <NUM>. When the knob <NUM> is in the first position, the positioning protrusion <NUM> is located at one of two sides of the flexible clamping portion <NUM>, and when the knob <NUM> is switched from the first position to the second position along the axial direction I1, the flexible clamping portion <NUM> is displaced by the positioning protrusion <NUM> such that the positioning protrusion <NUM> is switched to the other one of the two sides of the flexible clamping portion <NUM>.

To be more specific, the inner surface <NUM> has an upper region <NUM> and a lower region <NUM>. The upper region <NUM> includes a vertical section (not labeled) and an inclined section (not labeled). The vertical section is connected to the inclined section, and the inclined section is connected to the lower region <NUM>. The flexible clamping portion <NUM> includes four clamping arms <NUM>, and each of the clamping arms <NUM> protrudes from the inclined section toward the hollow space T2 to form a clamping end <NUM> of lipped structure. The positioning shaft <NUM> can further include a base portion <NUM> and a shaft portion <NUM>. The shaft portion <NUM> is disposed at the base portion <NUM>, and the positioning protrusion <NUM> is located at the shaft portion <NUM>. Hence, the positioning shaft <NUM> can be put upward into the hollow space T2 to engage with the flexible engaging portion <NUM>, and the base portion <NUM> can be limited in the lower region <NUM>. The fastening device <NUM> can further include a screw member <NUM>. The screw member <NUM> connects the positioning shaft <NUM> to the knob <NUM> such that the positioning shaft <NUM> is linked up with the knob <NUM>.

When operation of the knob <NUM> causes the positioning shaft <NUM> to move upward along the axial direction I1, the positioning protrusion <NUM> pushes the four clamping arms <NUM> such that the four clamping arms <NUM> are displaced radially, and the positioning protrusion <NUM> can move from one of the two sides of the flexible clamping portion <NUM> to the other one of the two sides side of flexible clamping portion <NUM>. Subsequently, the four clamping arms <NUM> are restored such that the knob <NUM> can remain in the second position.

The winding track T1 is configured for a lace (not shown) to wind thereabout. The case unit <NUM> can further include two lace holes <NUM>. The two lace holes <NUM> are located at the lower wall portion <NUM>, and the lace holes <NUM> can communicate with the lower chamber S12. Consequently, the lace can go out or drawn back into the lower chamber S12 to be released from or wound about the winding track T1 via the two lace holes <NUM>.

The knob <NUM> can include a plurality of first driving teeth <NUM>, and the engaging unit <NUM> can include a plurality of first combining teeth <NUM>. When the knob <NUM> is in the first position, the first driving teeth <NUM> are engaged with the first combining teeth <NUM>, and when the knob <NUM> is in the second position, the first driving teeth <NUM> are disengaged from the first combining teeth <NUM>. Additionally, the knob <NUM> can further include a cap body <NUM> covering on the case unit <NUM>, a post <NUM> disposed at the cap body <NUM> and protruding into the through hole <NUM>, and a plurality of second driving teeth <NUM> located at a distal end of the post <NUM> to couple to the spool <NUM>.

The cap body <NUM> of the knob <NUM> includes an inner top surface (not shown), and the post <NUM> protrudes downward from the inner top surface. The second driving teeth <NUM> are located at an outer surface of the post <NUM>, and the first driving teeth <NUM> are located at the inner top surface and surround the post <NUM>. The engaging unit <NUM> can include a hollow ring body <NUM>, and the first combining teeth <NUM> are located at the top end of the hollow ring body <NUM>. When the cap body <NUM> and the case unit <NUM> are assembled, the post <NUM> can protrude into the through hole <NUM> such that the second driving teeth <NUM> are engaged with a plurality of second combining teeth (not shown) which are located at the upper region <NUM> to allow the knob <NUM> to couple to the spool <NUM>.

In the embodiment, the engaging unit <NUM> can further include a plurality of pawl arms <NUM>, and each of the pawl arms <NUM> protrudes outward from the hollow ring body <NUM>. Each of the pawl arms <NUM> is engaged with at least one of the mounting teeth <NUM> in the first direction R1 to prohibit the engaging unit <NUM> from rotating in the first direction R1. On the other hand, each of the pawl arms <NUM> is disengaged from the mounting teeth <NUM> in a second direction R2 opposite to the first direction R1, and the engaging unit <NUM> is allowed to rotate in the second direction R2 relative to the case unit <NUM>.

When the knob <NUM> is in the first position, as shown in <FIG>, the first driving teeth <NUM> of the knob <NUM> are engaged with the first combining teeth <NUM> of the engaging unit <NUM>, and the second driving teeth <NUM> of the knob <NUM> are engaged with the second combining teeth of the spool <NUM> such that rotation of the knob <NUM> by a user in the second direction R2 causes the pawl arms <NUM> to disengage from the mounting teeth <NUM>, and the spool <NUM> can be linked up with the knob <NUM> to retract the lace. On the contrary, when the knob <NUM> is released by the user, each of the pawl arms <NUM> can engage with at least one of the mounting teeth <NUM>, and rotation of the knob <NUM> is limited by the engaging unit <NUM>. Meanwhile, rotation of the spool <NUM> in the first direction R1 is inhibited, and the lace is fastened.

When the user is looking forward to release the lace, as shown in <FIG>, the knob <NUM> can be raised along the axial direction I1. The first driving teeth <NUM> of the knob <NUM> are disengaged from the first combining teeth <NUM> of the engaging unit <NUM>, and the second driving teeth <NUM> of the knob <NUM> are disengaged from the second combining teeth of the spool <NUM>. As a result, rotation of the knob <NUM> and the spool <NUM> are not inhibited by the engaging unit <NUM>. In other embodiment, when the knob is in the second position, the engagement between the second driving teeth of the knob and the second combining teeth of the spool can be remained, but the present disclosure is not limited thereto.

<FIG> shows a three dimensional schematic view of a fastening device 100a according to another embodiment of the present disclosure. <FIG> shows one exploded view of the fastening device 100a of <FIG>. <FIG> shows another exploded view of the fastening device 100a of <FIG>. <FIG> shows one cross-sectional view of the fastening device 100a of <FIG>. <FIG> shows another cross-sectional view of the fastening device 100a of <FIG>. The structure of the fastening device 100a is similar to the structure of the fastening device <NUM>, but the spool 300a is coupled to the knob 500a in a different way.

To be more specific, the knob 500a can further include a cap body 510a, a post 520a and a plurality of second driving teeth 530a. The cap body 510a covers on the case unit 200a. The post 520a is disposed at the cap body 510a and protrudes into the through hole (not labeled), and the second driving teeth 530a are located at a distal end of the post 520a. The fastening device 100a further includes a gear assembly 800a, and the gear assembly 800a includes a sun gear 810a and a plurality of planetary gears 820a. The sun gear 810a is engaged with the second driving teeth 530a. A number of the planetary gears 820a is four in the embodiment, and the planetary gears 820a are spaced away from each other. Each of the planetary gears 820a is engaged with the sun gear 810a. The case unit 200a can further include a plurality of inner teeth 280a located at the lower chamber S12 and engaged with the planetary gears 820a.

The post 520a include a cave (not labeled) located at the distal end. The second driving teeth 530a are located within the cave. The sun gear 810a is engaged with the cave to engage with the second driving teeth 530a. The spool 300a includes four pivotal shafts 350a configured for the planetary gears 820a to be pivoted thereon. The partition 230a protrudes inwardly from a middle part of the upper wall portion 221a. The upper wall portion 221a can be deemed to be separated by the partition 230a such that the upper chamber S11 can be formed by the upper section of the upper wall portion 221a, and the lower chamber S12 can be formed by the lower section of the upper wall portion 221a, the lower wall portion 222a and the base (not labeled). The inner teeth 280a can be disposed within the lower section of the upper wall portion 221a. When the knob 500a is rotated, the sun gear 810a is driven by the second driving teeth 530a, and the planetary gears 820a will rotate and move along the inner teeth 280a to rotate the spool 300a.

Therefore, as shown in <FIG>, when the knob 500a is in the first position, the first driving teeth 540a of the knob 500a are engaged with the first combining teeth 410a of the engaging unit 400a, and the second driving teeth 530a of the knob 500a are engaged with the gear assembly 800a such that rotation of the knob 500a by a user in a second direction causes the pawl arms 420a to disengage from the mounting teeth 240a, and the spool 300a can be linked up with the knob 500a to retract the lace. On the contrary, when the knob 500a is released by the user, each of the pawl arms 420a can be engaged with at least one of the mounting teeth 240a, and rotation of the knob 500a is limited by the engaging unit 400a. Meanwhile, rotation of the spool 300a in the first direction is inhibited, and the lace is fastened.

Claim 1:
A fastening device (<NUM>, 100a), comprising:
a case unit (<NUM>, 200a), comprising:
a wall (<NUM>) forming a receiving space; and
a plurality of mounting teeth (<NUM>, 240a) located at the wall (<NUM>) and facing toward the receiving space;
a knob (<NUM>, 500a) covering on the case unit (<NUM>, 200a); and
an engaging unit (<NUM>, 400a) within the receiving space, the engaging unit (<NUM>, 400a) corresponding to the mounting teeth (<NUM>, 240a) and selectively coupled to the knob (<NUM>, 500a);
wherein the knob (<NUM>, 500a) is switched between a first position and a second position along an axial direction (<NUM>), when the knob (<NUM>, 500a) is in the first position to couple to the engaging unit (<NUM>, 400a), the engaging unit (<NUM>, 400a) is linked up with the knob (<NUM>, 500a) and the engaging unit (<NUM>, 400a) is engaged with one of the mounting teeth (<NUM>, 240a) to prohibit the knob (<NUM>, 500a) from rotating in a first direction (R1);
characterized by,
wherein when the knob (<NUM>, 500a) is in the second position to disengage from the engaging unit (<NUM>, 400a), the engaging unit (<NUM>, 400a) is remained in an original position and does not prohibit the knob (<NUM>, 500a) from rotating in the first direction (R1).