UMBRELLA CANOPY MECHANISM

FIELD OF THE INVENTION

This invention relates to the field of mechanisms for opening and closing umbrellas, more specifically strutless umbrellas.

BACKGROUND OF THE INVENTION

Strutless umbrella is a type of umbrella having canopy ribs with no struts supporting them to the umbrella stick. The appearance of strutless umbrellas is believed to be neater and more elegant comparing to that of conventional umbrellas i.e. umbrellas that do have struts. Furthermore strutless umbrellas provide for improved protection from rain and wind since they enable users lowering the canopy very close to the user's head.

One problem that should be addressed when designing strutless umbrellas is the dimensions of the folded umbrella, which should preferably not significantly exceed the dimensions of conventional umbrellas. It will thus be advantageous to have canopy deployment and closing mechanism which will provide for substantially normal diameter of the folded strutless umbrella.

Reduction in the weight of umbrellas, whether or not they are strutless, will also be welcomed by users. The motivation of umbrella designers to reduce the number and weight of umbrella components is obvious.

US 5,711,234 discloses a strutless umbrella which includes a central post, either an inner plunger or a tube, a canopy assembly including ribs pivotally mounted on the upper end of the central post. Links connect the ribs to the inner plunger or tube.

Movement of one of the ribs moves the plunger or tube which in turn moves the remaining ribs. A latch pin holds the umbrella in the open position.

US 5,638,846 discloses an umbrella having a simplified construction which dispenses with the stretcher members (struts) of conventional umbrellas and has one end hinged to the central portion of each rib. Said umbrella includes a runner (4) axially slidable along the umbrella pole (1) between a folded position in which the ribs (3, 3') can be folded against the pole, and an unfurled position in which the runner engages the ribs and holds them in the extended position. For this purpose, the runner comprises an upper frusto-conical portion (46) engageable with the ends (35) of the reinforcing portions (31) of the ribs.

US 4,736,761 illustrates umbrella mechanism inter-alia aimed at reducing the number of umbrella components from about 91 in conventional umbrellas to 43 in one of its embodiments as mentioned in column 5 lines 13-14.

SUMMARY OF THE INVENTION

The present invention relates to an umbrella canopy mechanism, to be mounted on an umbrella stick having a near canopy end (hereinafter will be referred to as 'upper end ¹ ) and a near handgrip end (hereinafter will be referred to as 'lower end'), the mechanism comprises a spindle having a limited extent of linear movement near the upper end of the stick; a plurality of angularly spaced umbrella ribs pivotally connected near the stick's upper end, such that a variable angular space between each rib and the stick is formed; an edge of each rib is substantially rounded about a radius centered at the pivot connection, and is engaged to the spindle in a tangential area between the spindle and the rounded edge, by friction or by mutually engagable series of teeth (this engagement between the spindle and the rounded edge of a rib will be referred to hereinafter in the term gearing); such that the linear movement of the spindle results in a correlated shift of the tangential area along both the spindle and the rounded edge, and in varying the angle between each rib and the stick .

According to some preferred embodiments the spindle has a general cylinder- like shape (having a horizontal cross section of a circular shape). According to other it has a general box shape having a plurality of planner side faces (having a horizontal

cross section of a polygonal shape) in a number according to the number of canopy ribs in the umbrella.

The gearing between the end of the rib and the spindle may be by a plurality of mutually engageable protrusions and recesses, by mutually engageable toothed surfaces, or by friction gearing. The outer surface of the cylinder-like or box-like spindle may thus have protrusions and grooves along its height, to face respective matching grooves protrusions located on the rounded edge of each rib.

The rib's rounded edge and the protrusions may be of the same piece of material from which the rest of the rib is formed, or a separate piece attached to the rest of the rib. For example, the whole rib including a rounded end having gearing teeth can be made of one piece of polymeric material. Alternatively, the rounded end with its gearing teeth can be made from a piece of metal attached to a plastic made rib's body together forming the rib. The piece of metal may further include hinge hole or hinge axis for the pivotal connection of the rib to the stick's upper end.

Some gearing options between the round rib ends and the spindle can be taught from publications relating to cork extractors of the type disclosed by e.g. US 5,934,160 and US 6,799,490. Methods how to pivotally connect the ribs about the stick can also be taught from such publications. The umbrella ribs in the mechanism of the present invention are analogous to the levers (handles) existing in cork extractors of said type, for example item 16 in the figures of US 6,799,490, or items 30, 36, 230, 236 in the figures of US 5,934,160.

Some basic differences exist, however, between the mechanism of said type of cork extractor and that of the canopy mechanism of the present invention. These should be considered by umbrella designers.

One example of a basic difference is the direction of acting forces. While in the cork extractor mechanism the levers (handles) are aimed to force the spindle (rack) upwardly by man power acting on them, in the canopy mechanism of the present invention the ribs (that are analogous to said levers or handles) are driven up or down by respective linear motion of the spindle.

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Another difference is in that the force required for extracting a normal cork is significantly greater than the force required for controlling umbrella ribs. On the other hand, the lever advantage (measured as the ratio between the length of umbrella's rib or extractor's handle and the radius of its rounded end) will normally be much greater in umbrella than in cork extractor. Furthermore, umbrellas usually contain between six and ten ribs while cork extractors contain between one and two handles.

An additional difference is that in cork extractors the spindle is normally aimed to revolve (additionally to is capability of linear movement) for driving the corkscrew into the bottle plug, while in the canopy mechanism of the present invention the spindle need not be capable of revolving (although it may, if so desired).

It should also be noticed that while the pivoting angle of umbrella rib is normally less than 90 degrees, the pivoting angle commonly applicable for levers (handles) of cork extractors of the above indicated type is about 180 degrees. This may influence the design of the rounded end (which in case of a canopy rib may extend about only a quarter of a circle), and - the extent of linear motion of the spindle, respectively.

It is noted however that 180 degree pivoting may be provided in canopy mechanism if so required. This may be of help e.g. for allowing the option of folding the umbrella in reverse mode as suggested by JP 11164717 publication for setting the wet surface of the umbrella internally, or e.g. for facilitating mounting a canopy cloth on the ribs either during manufacturing process or for the purpose of cloth replacement.

The definition of "rounded" when relating to the rib end means that the end of the rib is arched in a radius about the axis about which the rib pivots when opening or closing the umbrella, so as to maintain gearing between the rib end and the spindle during pivoting of the ribs.

Linear motion of the spindle may be generated by e.g. manual power either directly or through a spring, by force of electrical motor, or by force of compressed gas.

In case the origin of driving force is through circular motion e.g. of user's hands or of a revolving motor, the circular motion can be converted to respective linear motion of the spindle, e.g. by means of helical drive shaft or threaded shaft.

The present invention further relates to an umbrella including umbrella stick having a near canopy end (hereinafter will be referred to as 'upper end ¹ ) and a near handgrip end (hereinafter will be referred to as lower end'), and a canopy mechanism comprising a spindle capable of a linear motion of predetermined extent near the stick's upper end (e.g. by a driving mechanism located in a handle of the umbrella and coupled to the spindle by a shaft passing through the inner space of a hollow umbrella stick), a plurality of umbrella ribs angularly spaced and pivotally connected about the stick's upper end, each rib has a rounded end geared to the spindle such that a linear motion of the spindle between extremes of said predetermined extent forces the rib pivoting between closed and deployed states of the ribs.

The present invention relates also to a method for producing umbrellas based on the invented canopy mechanism, comprising providing a canopy cloth having a central opening and a plurality of radial rib receiving sleeves spaced angularly about the central opening; providing a plurality of umbrella ribs each having a rounded end configured for gearing to a spindle; providing a hub comprising a plurality of angularly spaced seats each configured for a pivotal connection of one umbrella rib; providing a top closure connectable to the hub; inserting a plurality of umbrella ribs to a corresponding plurality of rib sleeves; connecting the top closure to the hub with the canopy containing the ribs pivotally attached between the hub and the top closure, with the central opening concealed by the top closure and with the spindle geared to the rounded ends of the ribs.

According to a first embodiment of the production method the insertion of the ribs to the sleeves is performed before the ribs are seated in the hub. According to this embodiment the canopy cloth containing the ribs situated in the sleeves is then brought as a whole to a position on the hub by positioning each rib in a seat in the hub. According to some variations of this embodiment the spindle is provided in the center of the hub first, then the canopy containing the ribs is brought to a connection with the hub. According to other variations of this embodiment the canopy containing the ribs is brought first to a position on the hub, thereafter the spindle is provided in the center of the hub for becoming geared to the rounded ends of the ribs. According to some additional variations of this embodiment the spindle is first brought to a contact with the

rounded ends of the ribs, then the canopy containing the ribs in its sleeves and the spindle in the center between the ribs are brought to a position on the hub.

According to another embodiment of the production method the insertion of the ribs to the sleeves is performed after the ribs has already been seated in the hub and are geared to the spindle. According to this embodiment the insertion of the ribs into the canopy sleeves is by first rotating the ribs to a reverse position in which each rib will form an angle of about 180 degrees with the stick of the umbrella (which at this stage has not necessarily been mounted), then by guiding the free end of each rib to an opening of respective canopy sleeve (or equivalently be guiding the opening of the sleeves towards the free end of respective ribs) and by pulling the canopy cloth about the ribs such that the ribs being simultaneously inserted into the canopy sleeves. Thereafter, the ribs are rotated back to a normal position and the top closure is mounted on the hub covering the central opening of the canopy while sandwiching the cloth which surrounds the opening between the hub and the top closure.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Fig. 1 is a vertical cross sectional view through the axis of symmetry of an exemplary embodiment of canopy mechanism according to the present invention in deployed state.

Fig. 2 is a vertical cross sectional view through the axis of symmetry of an exemplary embodiment of canopy mechanism according to the present invention in closed state.

Fig. 3 is a top view over a ribs hub of the mechanism of Fig. 1 before positioning its top closure.

Fig. 4 is a partial exploded isometric view of an exemplary embodiment of the canopy mechanism according to the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Fig. 1 is a vertical cross sectional view through the axis of symmetry S of an exemplary embodiment of canopy mechanism 1 according to the present invention in a deployed state of the umbrella. The canopy mechanism is mounted on an umbrella stick 4 having upper and lower ends (23 and 3 respectively), and includes a spindle 9 configured to a predetermined extent X of linear movement near the stick's upper end 23, a plurality of umbrella ribs 5 pivotally connected near the stick's upper end 23 and angularly spaced from each other, each having a rounded end 13 geared to the spindle 9 such that the rib 5 forms a variable angle with the stick 4 responsive to changes in a position of the spindle 9 within the extent of movement X (i.e. the angle between the rib and the stick is in correlation with the position of the spindle within the extent, thus being controllable by the spindle).

The spindle's movement extent can be measured e.g. respective to the upper edge of the spindle as a reference, which according to the illustrated example can vary its location between the lines 11 and 21 delimiting its predetermined extent X of linear movement.

Further in the illustrated example rib hub 2 is connected to the upper end 23 of the umbrella stick 4. A plurality of umbrella ribs 5 are connected pivotally to a respective plurality of pairs of rib holders 6 such that each rib is hinged between two holders 6. The hinging is by a pair of protrusions 7 located from both rib sides (only one can be seen in each of the illustrated ribs in this figure) to form a pivot axis near the proximal end of each rib. The radius of the rounded section 13 with which each rib ends is marked R and is centered at a mid point between the pair of protrusions 7. The protrusions are situated in respective pair of recesses (referred to also as seats) 16, not shown in this figure, made in the rib holders 6. The rounded section 13 is provided with gearing teeth 8 on its outer surface. The teeth 8 are geared to the spindle 9. The spindle is configured to an up and down vertical movement along a predetermined extent of the axis S. In this Fig. the spindle is seen in its extreme down position, which corresponds to the illustrated deployed position of the ribs 5. As long as the spindle is maintained in

this position the ribs will remain deployed since they are barred from pivoting due to their gearing teeth 8 interlocked within matching gearing grooves 10 spaced from one another along the length of the spindle 9. By moving the spindle upwards toward an extreme upper position marked by line 11, the ribs 5 will be forced to pivot downwards as indicated by arrows 12 until reaching a closed position juxtapose the stick when the spindle has reached its max up position. The latter state is illustrated by Fig. 2.

Moving the spindle may be performed by a shaft (not illustrated) passing along the inner space of the stick 4. The shaft may be secured to the bottom end 37 of the spindle e.g. by means of threading 38 matching an inner threading made inside the top end of the shaft. The shaft may have a polygonal cross section having outer dimensions slightly smaller than the inner dimensions of a matching polygonal tunnel 39 made through the hub collar 18. The polygonal shape allows for linear movement of the shaft (and thus of the spindle) while preventing shaft's rotation thus securing its threading connection with the spindle from unintentional opening by relative rotation between these parts. In the illustrated embodiment the collar comprises an insert 19 through which a hexagonal tunnel 39 is formed. The wall of the top end 23 of the stick 4 is stressed between the insert 19 and the collar 18. The connection between the stick and the collar may be further secured by gluing or by a wedge crossing transverse the stick's wall and the collar.

According to another embodiment the shaft and the spindle are formed as one integral unit, i.e. the bottom end of the spindle extends through the inner space 39 of the hub collar 18 and down the inner space of the stick 4.

The linear motion of the shaft may be achieved e.g. by electrical motor located in a handgrip of the umbrella and coupled to the shaft through a screw drive or helical drive for converting motor rotation to linear motion of the shaft and the spindle. Alternatively, the movement of the shaft can be made manually by either a manual helical drive configured to convert manual rotation to a linear motion of the shaft or by a manual push-handle connected to the bottom end of the shaft.

It can be appreciated that since teeth 8 are always interlocked within grooves 10 of the spindle, there will be provided a substantial correlation between a current location of the spindle 9 along its permitted extent of linear movement and a respective current

angle the ribs 5 form with the stick 4. The canopy may thus be maintained in any desired degree of deployment by holding the spindle immovable in a corresponding position along its vertical movement path. Accordingly, a user is able to pass with the umbrella through narrow passage ways e.g. through a car door, with a partially deployed umbrella, then continue opening the umbrella outside the car. Furthermore, in windy weather the umbrella can be used in a partial deployment in order to avoid inverting the canopy by wind as usually happen during the use of conventional umbrellas.

The hub 2 is closed from above by a top closure 22. The top closure has a tunnel 24 extending along the umbrella axis S, for accommodating the upper portions of the spindle during its linear movement. The inner diameter of the tunnel is made similar to the outer diameter of the spindle such that it guards the spindle from dirt while keeping it straight and avoiding its bending under high forces which might be acting on it during operation. The umbrella further comprises a cover 32 covering the center of the umbrella cloth 33. The cover 32 has a top opening through which passes an upper end 25 of the hub's top closure 22. The upper end 25 of the top closure terminates the tunnel 24 and is provided with a threading 26, so as to allow a tip cap 27 having inner threading matching the threading 26 to secure the cover 32 on top of the hub's top closure 22 with the central portion of umbrella cloth 33 covered by the cover 32.

Fig. 2 is a vertical cross sectional view through the axis of symmetry of the same exemplary embodiment of the canopy mechanism 1 illustrated by Fig. 1, this time in a closed state of the canopy (the canopy cloth is not illustrated in this figure). The spindle 9 is seen in its uppermost position which corresponds to a lowermost position of the ribs 5 which in this figure are shown closed against the stick 4.

As can be noticed in this Figure, the tangential area where the spindle and the rounded end of the rib are in contact (hereinafter will be referred to also as 'the gearing point') is more particularly between a lower region of the spindle and a lower region of the round section 13, while in Fig. 1 the gearing point between the spindle and the rib involves an upper region of the spindle and an upper region of the round section 13. It can accordingly be appreciated that when the spindle moves through mid positions

between the extremes of its linear movement, the tangential area is shifted such that mid portions of the spindle will be brought to a contact with respective mid portions of the round section 13 thus pivoting the rib respectively about its pivot axis protrusions 7.

Fig. 3 is a top view of the mechanism of Figure 1 with an open hub, i.e. before the positioning of the top closure 22 on the hub 2. A plurality of ribs 5 angularly spaced about umbrella's stick (not seen in this Fig.) are shown in deployed position (due to scale limitations only a proximal end of each rib is actually shown). Each rib 5 being pivotally connected to the stick through a rib hub 2 connected to the upper end of the stick. The pivot connection is by pairs of protrusions 7 made from both rib sides near the rib's proximal end (i.e. its end connected to the stick) to form a pivot axis. The pairs of protrusions 7 are situated in respective pairs of recesses 16 made in the rib holders 6 which in this example being formed as elevated members of the hub 2. Each rib holder

6 contains two recesses 16 each for receiving a respective protrusion 7 of a separate adjacent umbrella rib 5.

The ribs hub 2 (when closed by its top closure 22) prevents escape or separation of the ribs from the spindle, thus secures the gearing between the spindle 9 and the toothed end of each rib, such that the only substantial motion the ribs are capable of is pivoting about their protrusions 7 as a response to linear motion of the spindle 9 in a direction perpendicularly to the drawing plane. In the illustrated example the gearing teeth 8 are made tapered in their lateral dimension as approaching the spindle 9. This is in order to allow nesting the ends of eight ribs about a spindle of a relatively small diameter. The linear motion of the spindle is by a shaft (not illustrated) connected to or integral with the bottom end of the spindle. The shaft passes through a hexagonal tunnel 39 formed in the insert 19, to join a driving mechanism either manual or electrical, located in a handgrip of the umbrella.

For the purpose of description only five of a total of eight umbrella ribs 5 are illustrated in this Figure, while spaces in the hub for receiving the three remaining ribs are illustrated empty. Each rib receiving space in the hub contains a gap 15 formed between two rib holders 6 which are hub members elevating from the hub collar 18. The

gaps 15 extend downwards the hub in order to allow the ribs approaching near the stick when pivoting towards a closed state of the umbrella.

The hub 2 further has bores 36 made in the top surface of the rib holders 6, for receiving corresponding protrusions made in the bottom of the top closure 22. The connection between the bores 36 and the corresponding protrusions may be reinforced by screws each passing through a respective pair of protrusion and bore.

Fig. 4 is a partial exploded isometric view of an exemplary embodiment of the canopy mechanism according to the present invention. The mechanism includes a rib hub 2 having a collar 18 for connection on top of umbrella stick. The stick is to be secured to the hub's collar 18 by means of an insert 19 to be inserted into the inner space of the stick's end, with the stick's wall stressed between the inside of the collar 18 and the outside of the insert 19 (as noticeable in Fig. 1). The insert 19 includes protrusions 20 matching respective bores made in the hub. Eight canopy ribs 5 (only 2 are illustrated) each having a pair of protrusions 7 on opposite sides thereof, are to be pivotally connected to the stick's upper end by positioning the protrusions 7 in respective pairs of recesses (16 in Fig. 3) made in the rib holders 6.

After the protrusions 7 of all the eight ribs are situated in the respective recesses with their rounded surfaces geared to the spindle 9, the hub's top closure 22 may be connected to the hub 2 so as to secure the ribs by closing the recesses 16 from above thus preventing escape of the protrusions 7 from the recesses 16. Closing the hub by the top closure 22 may be executed with the ribs maintained in their closed position wherein each is filling the gap 15 made between its rib holders 6. Alternatively, the ribs may be maintained in any other desired position within their pivoting extent, during umbrella's assemblage.

The spindle's bottom end 37 is extended by a shaft (not shown) being either one piece with the spindle or an extension connected to it (e.g. through matching outer and inner threading made respectively on the shaft and on the bottom end of the spindle). The shaft passes through a tunnel 39 formed in the insert 19, and further extends

througli the inner space of the stick to reach at a driving mechanism located in a handgrip (not shown) of the umbrella connected to the lower end of the stick.

The driving mechanism may comprise a motor coupled to the shaft through a helical drive or through screw so that the revolutions of the motor are converted to a linear motion of the shaft and in turn of the spindle. The canopy would thus can be opened or closed, according the revolving direction of the motor. The revolving direction of the motor can be switched by a three options switching unit configured to switch the power and the polarity of a DC battery located in the handgrip and connected to the motor through the switching unit.

The exemplary canopy mechanism embodiment illustrated in Figures 1 — 4 is appropriate for producing plastic umbrellas, having strutless canopy ribs. It can be manufactured however from metal or from combination of metals, plastics, carbon-fiber reinforced plastics or other composite materials, without departing from the scope of the present invention.

It is adapted for either electrically powered umbrellas or manually operated umbrellas. Furthermore, both options (i.e. the electrical and the manual) may be integrated and implemented in one device so as to allow manual operation in case of any kind of failure of the electrical system.