Abstract:
A well-filler of variable width for a drop-center wheel including a band for circumposing the wheel rim in the well in engagement with a plurality of segments, the fist and second ends of the band being attached to mutually engageable connectors that are adjustable for tightening the band. When the band is fitted it tightens in the well and the segments are urged in directions transverse to the direction of the band so that the width of the well-filler matches that of the well.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a well-filler for retaining a tire on a drop-center wheel rim. 
     A common wheel design of has a rim (known as a drop-center rim) in which there is a comparatively narrow well which effectively reduces the diameter of the wheel all around its circumference. Such a well facilitates the mounting of a pneumatic tire on the wheel. One inextensible bead of a tire is slipped over the lip of a side flange of the rim and into the well and then the diametrically opposite part of that bead of the tire is then able to be passed over the flange and be mounted on the rim. Inflation of the tire forces the beads into their correct position with their feet engaged on slightly conical seats adjacent the flanges. 
     A major problem with wheels with drop-center rims is that without a device to fill the well there is a danger of the tire detaching itself upon a loss of air pressure, for example after a puncture. One of the beads may slip into the well and the mounting procedure for the tire be effectively reversed. This loss of concentricity involves loss of control, and is dangerous if it happens on a vehicle travelling at high speed. 
     Band devices for filling wheel wells are known. However, well-fillers of current designs have to be made individually for different types of wheel of different diameter and especially for wells of different effective widths. None of the known well-fillers is adjustable in width. In addition, current designs have to be made in different materials to suit steel and alloy wheels the properties of which vary differently with temperature and load changes. 
     SUMMARY OF THE INVENTION 
     According to the present invention there is provided a well-filler of variable width for a well of a drop-center wheel rim, the well-filler having a band for circumposing the rim in the well in engagement with a plurality of obstructor segments, and mutually engageable connector means at first and second ends of the band, the connector means being adjustable for tightening of the band in the well around the rim, engagement of the band with the segments being such that when the band is tightened in the well of a wheel rim the segments are urged in directions transverse to the band so that the width of the well-filler matches that of the well. 
     Preferably, the band extends through a channel in a body portion of each segment, the channel having an engagement surface to engage with a corresponding surface of the band, the engagement and corresponding surfaces being angled such that tightening of the band around the rim causes the segment support to be urged in a direction transverse to the band axis. The engagement surface on the band is preferably one of a pair of equally-inclined surfaces forming a V-shape in cross-section; these may respectively engage with an inclined engagement surface of the segments which is one of a pair of surfaces forming an equally inclined V-shape in cross-section. 
     Preferably, the segments are arranged so that alternate ones are urged towards opposite transverse directions. The segments may be substantially identical to each other but be oriented in opposite senses to achieve relative motion in opposite directions. 
     Preferably the obstructor segments are flexible so that they may curve to follow the arc of the band around the rim. 
     The connector means may be pivotally attached at the ends of the band and the position of their attachment to the band may be varied. This gives accommodation to the diameter of the wheel to which the device is to be applied. The connector means may be mutually engaged via a socket head screw and locking nut. The attachment of the connector means at the ends of the band then facilitates location of the screw in the nut. 
     In an alternative embodiment the band has a slot to receive a cable. When the slot is on an outer peripheral surface of the band it should be of sufficient depth so that the cable does not protrude from the band. At first and second ends of the cable, mutually engageable connector means may be rotatably attached, and the position of the connector means on the cable may be variable to provide a band whose length is adjustable according to the circumference of the well to which it is going to fit. 
     Preferably the connector means are provided with a shaped base portion to fit in the bottom of the channel in the end segments. This assists the correct alignment of the connector means, both during fitting and use, and stabilizes the ends of the band in use. 
     In a preferred embodiment, a top portion of the obstructor segments adjacent the connector means is absent to expose the bottom of the channel and further accommodate the connector means if they are too large to fit inside the channel as well as to facilitate fitting and removal of the well filler band. 
     Preferably, the connector means are such that once they are engaged and the band is tightened there is enough clearance between them for the valve of a tubed tire to protrude into the wheel well. 
     The connector means should desirably have no sharp edges or protrusions so that the well-filler is suitable for use with tubed and tubeless tires. 
     Preferably the device has alignment means to keep the segments in circumferential alignment on the band prior to tightening of the band. A protrusion on the segments may be engageable with a recess or groove in the band for this purpose. Alternatively, a protrusion on the band may be engageable with a recess or groove in the segments. Preferably the alignment means disengage automatically when the band is tightened. Each segment may have a hole through which tool may be inserted to facilitate disengagement of the alignment means. The tool may be a screwdriver. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings: 
     FIG. 1 shows a well-filler which is a first embodiment of the invention; 
     FIG. 2 shows a side view of the band seen in FIG. 1; 
     FIGS. 3 and 4 show cross-sections through the band on lines 3--3 and 4--4 of FIG. 2 respectively; 
     FIGS. 5 and 6 show connectors of the embodiment from above and from the side respectively; 
     FIG. 7 shows a cross-section through a drop-center wheel rim and the embodiment of a well-filler positioned in the well of the rim; 
     FIG. 8 shows a perspective cross-sectional elevation of a wheel rim and a well-filler which is a second embodiment of the present invention; 
     FIG. 9 shows a cross-section through the second embodiment with an obstructor segment and band alignment means; 
     FIG. 10 is a plan partial view of adjacent ends of the band and the connector means with the top portion absent; 
     FIG. 11 shows a perspective view of a connector in a variant of the present invention; 
     FIG. 12 shows the end view of the connector in FIG. 10; 
     FIG. 13 shows a perspective view of the complete connector and cable; 
     FIG. 14 shows the connector of FIG. 13 in an alternative condition; 
     FIG. 15 shows a perspective view of the end portion of an obstructor segment of FIG. 14; 
     FIG. 16 shows a fixing bolt, locking nut and rollers; and 
     FIG. 17 shows a roller. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In FIGS. 1-7, a well-filler according to an embodiment of the present invention, has a band 1 obstructor segments 2 and connector means 3 and 4. FIGS. 2, 3 and 4 show that the band has a pair of engagement surfaces 5 and 6 forming a V-shape in cross-section, with the V-shape being broader in a region at an end of the band than at a point between end regions. 
     In use, a well-filler is placed around a drop-center wheel rim 10 in well 11 of the rim. Connector means 3 and 4 are engaged and the band tightened. FIG. 7 shows a cross-section through a rim 10 with a well-filler in position in the well 11. 
     Band 1 extends through channel 12. Inclined surface 5 of the band is in sliding engagement with corresponding surface 7 of the channel so that force in the dissection of arrow X due to the tightening of the band 1 causes obstructor segment 2 to be urged in the direction of arrow Y transverse to the band 1. The obstructor segments 2 and 2&#39; are identical but are oriented in opposite senses so that they are urged in opposite directions on tightening of the band 1. Force in the direction of arrow X due to tightening of the band 1 causes obstructor segment 2&#39; to be urged in the direction of arrow Z. Alternate segments around the rim 10 are oriented so as to be urged in opposite directions towards opposite sides of the well 11. 
     Tightening of the band then causes the well-filler to expand width-wise until its width matches that of the well 11. 
     FIGS. 5 and 6 shows that the connector means 3 and 4 are pivotally attached at the ends of the band 1 by pins 13. The connector means 3 and 4 have several holes 14 through which a pin 13 may pass so that the position of attachment of the connector means 3 and 4 may be varied according to the diameter of the wheel to which the well-filler is to be applied. Connector 4 holds a socket cap screw 15 which engages with &#34;Nylock&#34; locking nut 16 contained in connector 3. The connector means 3 and 4 are moulded with no sharp edges or protrusions so that the well-filler is suitable for use with tubed and tubeless tires. 
     FIGS. 8 and 9 show a well-filler according to a second embodiment of the present invention which includes alignment means to keep obstructor segments 22 in alignment on the band 21 prior to tightening. The alignment means comprises a protrusion 23 on the segments 22 which is engageable with a slot 24 on the band 21. FIG. 8 shows the well-filler in the well 11 of rim 10 after tightening of the band 21. Segments 22 are urged transversely to the band 21 so that the width of the well-filler matches that of the well. Alternate segments 22 are urged in opposite directions towards opposite sides of the well 11. Gaps between the segments and sides of the well away from which they have moved are too narrow and cover too little of the circumference of the rim 1 for a tire to fall into them. Any forge from a tire bead falling even slightly into a gap will only push the associated segment harder into the opposite side of the well, so a segment cannot be dislodged by such a force. FIG. 9 shows the alignment means of band 21 and a segment 22 engaged prior to tightening of the band 21. In this embodiment, the segments have a hole 25 for insertion of a tool to facilitate disengagement of the alignment means on tightening of the band 21. The band 21 has bevelled surfaces 26 for engagement with a tool for this purpose. 
     FIG. 10 shows a partial plan view of adjacent ends 27,28 of a second embodiment of band 1&#39; and connector means 30,40. The connector means 30,40 are attached to a cable 31, which is itself received in a slot 20 along the length of the band 1&#39;. The connector means 30,40 are provided with rollers 32,33 which are rotatably received in said connector means 30,40 at right angles to the direction of the band 1&#39; and have apertures to allow a fixing bolt 35 to pass through and secure the band 1&#39; by means of a locking nut 34. The rollers 32,33 allow the fixing bolt 35 to articulate to compensate for the curvature of the drop center wheel rim 10. 
     The connector means 30,40 are provided with a V-shaped base 36 at the same inclination as the base 42 of the channel 12 through the obstructor segment 22. This helps to stabilize the connector means 30,40 in the base 42 of the channel 12 and allows free access to the connector means 30,40 for fitting and removal. 
     FIGS. 11 and 12 show respectively a perspective and an end view of the connector means 30,40. The V-shaped base 36 stabilizes the connector means 30,40 in the Base of the channel 12. FIG. 15 shows how a top portion of an obstructor segment 22 can be absent, exposing the channel 12 underneath. This permits the connector means 30,40 to be stabilized in the base 42 of the channel 12 and assists the correct alignment of the connector means 30,40 both during fitting and use. 
     The cable 31 is received in a slot 43 in the connector means 30,40 and retained there by an end stop 44. The roller 32 is rotatably received in the connecting means 30,40 at right angles to the direction of the well filler band 1&#39;. The fixing bolt 35 is pivotally retained in the aperture 48 in the curved face of the roller 32, to allow the connector means 30,40 to articulate to fit the curvature of the well 11. 
     FIGS. 13 and 14 show perspective views of the connector means 30,40 and cable 31. The cable 31 is provided with several stops 44,45 and so the length of the cable 31 can be varied by selecting the appropriate stop 44,45 for abutment against the connector end, to fit wheel rims of different circumference. 
     FIG. 16 shows the locking nut 34 and fixing bolt 35 used to secure the well filler band, together with rollers 32 to fit the connecting means 30,40. The locking nut 34 is fixed in position in a recess 50 in the roller 32,33 allowing the fixing bolt 35 to be adjusted with an allen key. FIG. 17 shows a perspective view of the roller 32,33 with an aperture and cutaway portion or recess 50 to receive a nut 34. 
     Well-fillers according to the present invention will retain a tire on a drop-center rim after loss of air pressure in the tire. They are suitable for use with tubed and tubeless tires, on steel and alloy wheels and are adjustable to fit a wide range of diameters of wheel and width of well. Unlike conventional well-fillers, they adjust to fit the rim to which they are applied. 
     Normal tire fitter&#39;s lubricant may be applied to the base of the wheel well prior to fitting of the well-filler to facilitate the motion of the obstructor segments as the band is tightened. Normal water and vegetable based tire fitter&#39;s lubricant evaporates quickly so this will not increase the likelihood of slippage of the well-filler in service.