This invention relates to an automatic foldable umbrella, more particularly to an automatic foldable umbrella which is operable effortlessly.

Referring to Fig. 1, a conventional automatic foldable umbrella as disclosed in U.S. Patent No. 6,684,893 B2 is shown to include a handgrip 1, an operating unit 2, a central shaft unit 3, a central spring 4, a top hub 5, a runner 6, a rib-and-stretcher unit 7, and a cord unit 8. The operating unit 2 has a retained protrusion 202 disposed on a movable ring 201 to be retained in a retaining hole 602 in the runner 6 so as to hold the central shaft unit 3 in a folded position while the central spring 4 is in a compressed state, a spring-biased actuator 203 pivotably mounted on the movable ring 201 to be turnable to disengage from or engage a retained block 801, and a push button 204 manually operable to move the movable ring 201. The central shaft unit 3 includes lower, middle and upper shafts 301, 302, 303 telescopically coupled to one another. The cord unit 8 has a connected end secured to the top hub 5, and extends to be wound on a pulley 601 mounted on the runner 6 and a pulley 501 mounted on the top hub 5 to terminate at an anchoring end that is secured with the retained block 801. The retained block 801 is retained at a retaining region 301' of the lower shaft 301 to hold the cord unit 8 in a tensed state so as to maintain the rib-and-stretcher unit 7 in a spread position when the central shaft unit 3 is moved to an extended position by the biasing action of the central spring 4, as shown in Fig. 2, and is removed from the retaining region 301' upon a movement of the actuator 203 initiated by operation of the button 204 so as to release the tensed cord unit 8 to thereby permit the runner 6 and the rib-and-stretcher unit 7 to displace to a collapsed position, as shown in Fig. 3.

However, since the central spring 4 must be made to have a biasing force sufficient to move the central shaft unit 3, the runner 6, and the rib-and-stretcher unit 7 to open the umbrella, a relatively large manual force is required to compress the central spring 4 for folding the central shaft unit 3, which is inconvenient to the user, especially for a woman or a child, and which may cause injury to the user once the user inadvertently lets the umbrella slips from his/her grasp during folding.

An object of the present invention is to provide an automatic foldable umbrella which can be operated easily and effortlessly so as to reduce the risk of the umbrella slipping from a user's grasp during folding.

According to this invention, the automatic foldable umbrella includes: a central shaft unit having upper and lower shafts which are telescopically coupled to each other along an axis, and which respectively have top and bottom ends; at least one middle shaft having upper and lower ends which are respectively inserted into and sleeved on the upper and lower shafts; and an inner tube which has an attachment end that is disposed to be moved with one of the upper and middle shafts and which extends downwardly to terminate at an abutment end. The lower shaft has a retaining region. A central spring is disposed in the lower shaft to bias the middle shaft to move relative to the lower shaft from a folded position to an extended position. A top hub is disposed on the top end of the upper shaft. A runner is sleeved on and movable relative to the upper shaft between distal and proximate positions relative to the top hub. A rib-and-stretcher assembly pivotally interconnects the top hub and the runner so as to be moved from a collapsed position to a spread position when the runner is displaced from the distal position to the proximate position. A first force transmitting unit includes: a first direction reversing member disposed on the upper shaft and distal from the top end; a second direction reversing member disposed on the middle shaft adjacent to the upper end; a first cord having a first connected end tensely moved with the top end of the upper shaft, a first cord segment which extends downwardly from the first connected end in the upper shaft to be wound on the first and second direction reversing members, and further downwardly into the inner tube, and which terminates at an anchoring end; and a retained member which is connected with the anchoring end and which is displaceable between retained and released states, where the retained member is retained with and removed from the retaining region, respectively. When the middle shaft is biased to move from the folded position to the extended position, and when the retained member is kept in the retained state, the first direction reversing member is pulled up by the first cord segment to move toward the second direction reversing member so as to displace the upper shaft to a stretched-out position. When the retained member is displaced to the released states, the first direction reversing member is set free and is allowed to descend, thereby permitting the upper shaft to move downward relative to the middle shaft to a retracted position while the rib-and-stretcher assembly is displaced to the collapsed position. A second force transmitting unit includes: a third direction reversing member disposed on the upper shaft adjacent to the top end, and a second cord having a second connected end tensely moved with the middle shaft, and a second cord segment which extends upwardly from the second connected end to be wound on the third direction reversing member and which is led downwardly to terminate at a third connected end that is connected to the runner. The runner is moved from the distal position to the proximate position when the upper shaft is displaced from the retracted position to the stretched-out position.

Since the upper shaft can be moved downward relative to the middle shaft when the rib-and-stretcher assembly is collapsed, a compression force required to displace the central shaft unit to the folded position is significantly reduced. Hence, the folding operation of the central shaft unit can be conducted in a convenient and effortless manner.

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments of the invention, with reference to the accompanying drawings, in which:

• Fig. 1 is a sectional view of a conventional automatic foldable umbrella in a folded state;
• Fig. 2 is a sectional view of the conventional automatic foldable umbrella in a spread state;
• Fig. 3 is a sectional view of the conventional automatic foldable umbrella in a collapsed but extended state;
• Fig. 4 is a sectional view of the first embodiment of an automatic foldable umbrella according to this invention in a folded state;
• Fig. 5 is a sectional view of the first embodiment in a spread state;
• Fig. 6 is a sectional view of the first embodiment in a collapsed but extended state;
• Fig. 7 is an exploded perspective view of a portion of a central shaft unit of the first embodiment;
• Fig. 8 is a sectional view of the second embodiment of an automatic foldable umbrella according to this invention in a folded state;
• Fig. 9 is a sectional view of the second embodiment in a spread state; and
• Fig. 10 is a sectional view of the second embodiment in a collapsed but extended state.

Before the present invention is described in greater detail, it should be noted that same reference numerals have been used to denote like elements throughout the specification.

Referring to Figs. 4 and 5, the first embodiment of an automatic foldable umbrella according to the present invention is shown to comprise an operating unit 10, a central shaft unit 30, a central spring 40, a top hub 50, a runner 60, a rib-and-stretcher assembly 70, a first force transmitting unit 80, and a second force transmitting unit 90.

The operating unit 10 has a mounting shell 11, a spring-biased push button 12 which is manually movable relative to the mounting shell 11 and which has a retaining portion 121, an actuator 13 which is pivota by mounted on the push button 12 and which has an engageable end 131 that is turnable between non-actuatable and actuatable positions, and a torsion spring 14 disposed to bias the actuator 13 to the actuatable position.

The central shaft unit 30 includes upper and lower shafts 32, 31 which are telescopically coupled to each other along an axis (L), and which respectively have top and bottom ends 320, 310 that are respectively mounted in the top hub 50 and the mounting shell 11, at least one middle shaft 33 having upper and lower ends 334, 335 which are respectively inserted into and sleeved on the upper and lower shafts 32, 31, and an inner tube 34 which has an attachment end 343 that is secured to the top hub 50 and which extends downwardly to terminate at an abutment end 344 that is not beyond the upper shaft 32 . In particular, the retaining portion 121 and the actuator 13 of the operating unit 10 are disposed opposite to each other in terms of the axis (L). Further, the lower shaft 31 has a retaining region 311 adjacent to the bottom end 310, and an abutment region 312 located above the retaining region 311.

With reference to Fig. 7, the upper shaft 32 has an outer passage 321 disposed offset from the axis (L) . The middle shaft 33 has a plug 331 which is disposed in the upper end 334 and which has a through hole 333 that extends along the axis (L) such that the inner tube 34 is slidably fitted through the through hole 333. The inner tube 34 surrounds the axis (L) to define an inner passage 341, and an axial slot 342 configured to communicate the outer passage 321 with the inner passage 341.

The central spring 40 is a compression spring 40 which is disposed in the lower shaft 31 and which abuts against the abutment region 312 and the plug 331 to bias the middle shaft 33 to move upwardly relative to the lower shaft 31 from a folded position to an extended position.

The runner 60 is sleeved on and movable relative to the upper shaft 32 between distal and proximate positions relative to the top hub 50.

The rib-and-stretcher assembly 70 pivotally interconnects the top hub 50 and the runner 60 so as to be moved from a collapsed position to a spread position when the runner 60 is displaced from the distal position to the proximate position.

The first force transmitting unit 80 includes a first direction reversing member 83 disposed in the outer passage 321 of the upper shaft 32 and distal from the top end 320, a second direction reversing member 84 disposed on the plug 331 of the middle shaft 33, a first cord 81 having a first connected end 811 which is secured in the outer passage 321 adjacent to the top end 320, a first cord segment 813 which is disposed in the outer passage 321, which extends downwardly from the first connected end 811 to be wound on the first and second direction reversing members 83, 84, and further downwardly through the axial slot 342 into the inner passage 341 of the inner tube 34, and which terminates at an anchoring end 812, and a retained member 82 which is connected with the anchoring end 812.

The second force transmitting unit 90 includes a third direction reversing member 94 disposed on the upper shaft 32 adjacent to the top end 320, and a second cord 95 having a second connected end 91 secured to the plug 331 of the middle shaft 33, and a second cord segment 93 which extends upwardly from the second connected end 91 to be wound on the third direction reversing member 94 and which is led downwardly to terminate at a third connected end 92 that is connected to the runner 60.

In this embodiment, the first, second and third direction reversing members 83, 84, 94 are pulleys which are pivotally mounted on a lower portion of the upper shaft 32, the upper end 334 of the middle shaft 33, and an upper portion of the upper shaft 32, respectively.

As shown in Fig. 4, when the automatic foldable umbrella according to this embodiment is in a folded state, the runner 60 is held in the distal position by engagement of the retaining portion 121 in a retained hole 61 thereof to thereby place the central spring 40 in a compressed state, while the retained member 82 is in a retained state to be retained with the retaining region 311. In the meantime, the actuator 13 is kept by the lower end 335 of the middle shaft 33 in the non-actuatable position where the engageable end 131 is disengaged from the retained member 82.

As shown in Fig. 5, when it is desired to open the umbrella, the push button 12 is pressed manually to remove the retaining portion 121 from the retained hole 61 so as to release the runner 60. At this time, the middle shaft 33 is forced by the central spring 40 to move from the folded position to the extended position. Meanwhile, as a result of the retained member 82 being kept in the retained state, the first direction reversing member 83 is pulled up by the first cord segment 813 to move toward the second direction reversing member 84 so as to displace the upper shaft 32 to a stretched-out position, while the runner 60 is displaced from the distal position to the proximate position, thereby spreading the rib-and-stretcher assembly 70.

At this stage, the actuator 13 is turned to the actuatable position by means of the torsion spring 14 where the engageable end 131 is engaged with the retained member 82.

Referring to Fig. 6, when it is desired to close the umbrella, the push button 12 is pressed manually to move the actuator 13 to remove the retained member 82 from the retaining region 311 so as to place the retainedmember 82 in a released state. In the absence of a counteracting force exerted on the first cord segment 813 by the retained member 82, the first direction reversing member 83 is set free and is allowed to descend so as to permit the upper shaft 32 to move downward relative to the middle shaft 33 to a retracted position, while the rib-and-stretcher assembly 70 is displaced to the collapsed position. Further, the inner tube 34 is moved downward to permit the abutment end 344 to abut against the retained member 82.

When a manually pressing force is applied to move the top hub 50 and the mounting shell 11 toward each other for displacing the middle shaft 33 relative to the lower shaft 31 to the folded position, the inner tube 34 is pushed downward with the retained member 82 so as to being the retained member 82 back to the retained state. In the meantime, the middle shaft 33 is moved to displace the actuator 13 to the non-actuatable position, and the runner 60 is moved to and held in the distal position. Thus, the umbrella is locked in the folded state as shown in Fig. 4.

Referring to Fig. 6, since the upper shaft 32 can be moved downward relative to the middle shaft 33 when the rib-and-stretcher assembly 70 is collapsed, the compression force required to displace the central shaft unit 30 to the folded position is significantly reduced. Hence, the folding operation of the central shaft unit 30 can be conducted in a convenient and effortless manner, and the risk of the umbrella inadvertently slipping from a user's grasp during folding can be minimized. Furthermore, since only a smaller biasing force is needed for the central spring 40 to displace the middle shaft 33 relative to the lower shaft 31 to the extended position, possible injury to the user can be avoided.

Furthermore, since the first cord segment 813 is guided by and extends through the axial slot 342, the first direction reversing member 83 can be smoothly pulled without interfering with the movement of the middle and upper shafts 33, 32 and the central spring 40.

Referring to Figs. 8 to 10, the second embodiment of the automatic foldable umbrella according to this invention is shown to be similar to the first embodiment in construction. In the second embodiment, the attachment end 343' of the inner tube 34' is secured to the plug 331' of the middle shaft 33' and extends downwardly in the middle shaft 33' such that the abutment end 344' is not beyond the lower end 335' of the middle shaft 33'.