GB1598797A

GB1598797A - System for producing self-healing tyres

Info

Publication number: GB1598797A
Application number: GB4896477A
Authority: GB
Original assignee: Rockcor Inc
Current assignee: Rockcor Inc
Priority date: 1976-11-26
Filing date: 1977-11-24
Publication date: 1981-09-23
Also published as: IT1090702B; FR2372020B1; FR2372020A1; JPS53111378A; CA1116395A

Description

(54) SYSTEM FOR PRODUCING SELF-HEALING TYRES (71) We, ROCKCOR, INC. (formerly Rocket Research Corporation), a corporation organised under the laws of the State of Washington, U.S.A., of 11441 Willows Road, York Center, Redmond, Washington 98052, U.S.A., do hereby declare the invention, for which we pray that a patent may be granted to us and the method by which it is to be performed. to be particularly described in and by the following statement: This invention relates to a system for producing a self-healing tyre with a selfhealing sealant composition bonded to the interior of the tyre; to an applicator for applying a sealant composition to the interior of a tyre; and to methods of applying the sealant composition and of producing a tyre having a sealant composition applied to its interior surface.

Tyre cleaners are used in the production of self-healing tyres to remove mould release compounds and contaminants from the interior surfaces of the tyre in preparation for application of an air barrier coating or sealant. Self-healing tyres typically include a sealant or air barrier composition which is applied to the tyre interior by spray application to the interior tyre surfaces underlying the tread area, usually with gradual feathering into the sidewalls.

However, such tyres have been fabricated using uneconomical application techniques which did not afford automatic or mass production treatment of a large number of tyres.

According to this invention a system for producing a self-healing tyre with a selfhealing sealant composition bonded to the interior of the tyre is characterised by a sealant application means located at a sealant application station for applying sealant to the interior of a tyre and tyre conveying means associated with the sealant application station for carrying a plurality of tyres in side-to-side adjacency with their axes substantially coaxial, the tyre conveying means including means for transporting the tyre from the sealant application station to a tyre unloading station while continuously rotating the tyre about its axis from the time that sealant is applied to the tyre interior until the tyre reaches the unloading station.

The invention also includes a tyre sealant applicator for applying a sealant composition to the interior of a tyre and transporting the tyre from a loading station to an unloading station while continuously rotating the tyre about its axis from the time that a sealant composition is applied to the tyre interior until the tyre reaches the unloading station, which applicator comprises tyre conveyor means for carrying a plurality of tyres in side-to-side adjacency with their axes substantially coaxial from the loading station to the unloading station and for simultaneously rotating the tyres about their axes; and sealant application means for applying a sealant composition to the interior of a tyre when it is positioned at the loading station and rotated about its axis by the tyre conveyor means.

The invention also includes a tyre sealant application method which comprises positioning a tyre at a loading station; continuously rotating the tyre about its axis; applying a sealant composition to the interior of the tyre when positioned at the loading station during rotation thereof; and moving the tyre in an axial direction from the loading station toward an unloading station while continuing to rotate the tyre about its axis from the time that the sealant applying step is completed until the tyre reaches the unloading station, the tyre being moved axially upon completion of the sealant applying step a distance sufficient to clear the loading station to accept a fresh tyre; positioning a fresh tyre at the loading station following such axial tyre movement; and continuously rotating the tyres, includ ing the fresh tyre, and applying a sealant composition to the interior of the fresh tyre when positioned at the loading station during rotation of the tyres.

The invention also provides a method for producing tyres having a sealant composition applied to the interior surface of each tyre, the method comprising: applying a fluid sealant composition to the interior surface of a tyre while rotating the tyre to ensure even application of sealant; and conveying the tyre during a subsequent processing step in an axial direction while simultaneously rotating the tyre about its axis during a portion of the processing of the sealant composition to minimise flow of the sealant composition, the step of conveying the tyre in an axial direction including moving the tyre in sideto-side adjacency with at least one other tyre while simultaneously rotating the other tyre about its axis.

The invention will now be described by way of example with reference to the drawings in which: Figure I is a rear perspective view of the system for producing self-healing tyres; Figure 2 is a perspective view of the tyre cleaner with parts broken away; Figure 3 is a front end elevation of the Figure 2 cleaner; Figure 4 is a rear perspective view in enlarged scale of the cleaning head of the Figure 2 cleaner; Figure 5 is a rear side elevation of the Figure 4 cleaning head, depicting a tire in position for cleaning; Figure 6 is a schematic outline of the Figure 2 cleaner, depicting the tire drawer open and supporting a fresh tire, with the elevator lowered; Figure 7 is a schematic outline generally similar to Figure 6, depicting the tire drawer closed, and supporting a fresh tire in coaxial alignment with the cleaning head, with the elevator lowered; Figure 8 is a schematic outline generally similar to Figure 6, depicting the tire drawer closed, with the elevator raised and supporting a tire in position for cleaning with the cleaning head admitted into the tire between spread apart tire beads.

Figure 9 is a schematic block diagram of the control system of the Figure 2 cleaner; Figure 10 is a timing diagram depicting operation of the Figure 2 cleaner.

Figure 11 is a perspective view of the tire sealant applicator of this invention with parts broken away, together with a block diagram representation of the system for producing self-healing tires according to this invention; Figure 12 is a side elevation of the Figure 11 applicator, with parts broken away; Figure 13 is a fragmentary side elevation generally similar to Figure 12 but partially in section and on enlarged scale; Figure 14A is a fragmentary perspective on an enlarged scale of the spray applicator of the Figure 11 applicator, depicting the spray applicator in its lowered advanced application position; Figure 14B is a fragmentary perspective generally similar to Figure 14A, depicting the spray applicator in its raised advanced position; Figure 14C is a fragmentary perspective generally similar to Figure 14A, depicting the spray applicator in its raised retracted rest position; Figure 14D is a fragmentary perspective generally similar to Figure 14A, depicting the spray applicator in its lowered retracted purge position; Figure 15 is a section taken along the line 5-5 in Figure 12; Figure 16 is a schematic block diagram of the control system of the Figure 11 applicator; Figure 17 is a timing diagram depicting operation of the Figure 11 applicator.

The system and method for producing self-healing tires according to this invention, together with the tire cleaner for use therewith, are illustrated in Figure 1 of the drawings. The Figure 1 cleaner removes mold release agents, band ply lubricants and other contaminants from the interior surface or surfaces of a tire in preparation for subsequent sealant application. In the illustrated example, tires are manually loaded into a horizontally movable tire drawer (generally referenced by numeral 10) in which a tire is supported vertically between opposed vertical support plates 12, 14 and rests upon fixed horizontal support member 16 and rectractable horizontal stop 18. (The tire drawer is illustrated in Figure 1 in its open or retracted position, and is illustrated in Figure 2 with parts broken away in its closed or advanced position.) In the open position of drawer 10, the tire is spaced from but aligned coaxially with a stationary cleaning head generally referenced by numeral 20, and depicted schematically in Figure 6; in the closed position of drawer 10, the cleaning head is inserted within the tire wheel opening in coaxial alignment therewith and is spaced radially from the tire beads and adjacent interior surfaces.

Although the drawer is movable manually between its open and closed positions, it could be moved correspondingly by suitable automatic drive means if desired.

Following loading of a fresh tire and closure of the tire drawer as illustrated schematically in Figures 6 and 7, an elevator (generally referenced by numeral 22) lifts the tire from the tire drawer and moves it vertically toward the stationary cleaning head, as depicted schematically in Figure 8.

The cleaning head 20 is mounted in fixed vertical alignment with elevator 22. It includes two movable spreader rollers 24. 26 (Figure 4) for engaging and spreading the tire beads a distance sufficient to admit a powered cleaning brush 28, along with cleaning fluid application and removal apparatus, into the tire interior during such vertical movement of the tire by the elevator. (The spreader rollers are illustrated in Figure 4 in position ready for engagement with a tire and are illustrated in Figure 5 in their spread apart position.) The elevator further supports and rotates the tire with respect to the brush during cleaning while the spreader rollers, together with four additional fixed guide rollers, 30, 32, 34, 36, maintain the tire vertical and in alignment with the brush while preventing translational movement of the tire along the elevator.

Following tire cleaning. the elevator lowers the cleaned tire and repositions it upon the tire drawer which thereupon may be moved back toward its open or retracted position of Figure 1. The tire then may be discharged by retracting stop 18 manually and allowing the tire to drop upon an inclined discharge ramp 38 (partially shown in Figure 2) along which the tire rolls downward (to the right as illustrated in Figure 2) and out the rear discharge end of the cleaner. To accommodate tires of different sizes, the position of stop 18 may be varied along elongated slot 39. The stop 18, of course, could be retracted automatically or appropriately automated tire unloading apparatus substituted for stop 18, or ramp 38, or both.

In a system for producing a self-healing tires, the Figure 1 cleaner may be combined with appropriate sealant application apparatus 40. If required by the type of cleaning agent used. sealant used, temperature conditions and other factors, of course, appropriate heating apparatus 41 may be provided for heating the tires subsequent to cleaning and prior to sealant application. Likewise, additional heating apparatus 43 may be provided for heating the tire subsequent to sealant application. The applicator provides a sealant application station adjacent one end thereof. a tire unloading station adjacent the other end thereof, and an intervening sealant cure station. The applicator includes two elongated conveyor rollers 210, 212 arranged in parallel alignment and inclined from the application station toward the unloading station. These rollers simultaneously rotate a series of tires (referenced T1-T10 in Figures 11, 12) in the same direction about a common axis in side-byside engagement with one end tire adjacent the application station and the other end tire adjacent the unloading station. A movable sealant applicator (generally referenced by numeral 214) is located adjacent the application station for effecting airless spray application of a suitable tire sealant to end tire T1 during rotation thereof. A movable tire unloader or kicker assembly (generally referenced by numeral 216) is located adjacent the unloading station for unloading end tire T10 by engaging and moving it transversely to the common tire axis out of coaxial alignment with remaining tires T1- T9. Following unloading of tire T10, tires T1-T9 advance in series toward the position previously occupied by tire T10 and in this way make room along side now-advanced tire T1 for loading of a fresh tire adjacent the application station in the position formerly occupied by tire T1. In the example, fresh tires are positioned or loaded manually at the application station, although automatic loading apparatus could be used, if desired.

Thus, it will be appreciated that the sealant applied to the respective tires T1- T10 will be in various stages of set-up or cure, depending upon the position of a certain tire between the sealant application station and the unloading station during passage thereof through the sealant cure station. It is possible, therefore, by unloading tires T1-T10 at predetermined time intervals, to effectively control the time during which each tire is advanced from the sealant application station to the unloading station through the sealant cure station. In the illustrated example, the tires are conveyed from the application station to the unloading station for a time period which is sufficient to allow the sealant applied to set-up or substantially cure and which preferably represents a certain multiple of the time required to effect sealant application and advancement with respect to each tire.

In the example, ten tires are treated simultaneously for a period of about ten (10) minutes -- sealant application and tire advancement each consuming about thirty (30) seconds elapsed time. In other instances, of course, these time periods could vary, depending upon tire size, sealant application time required, type of sealant and other factors.

In a system for producing self-heating tires, the applicator may be combined with the tire cleaning apparatus and, if required by the type of cleaning apparatus or sealant used, appropriate pre-heat apparatus 41. In this instance, each tire may be maintained under coaxial rotational conditions therein with respect to a series of tires using conveyor rollers 210', 212' generally similar to rollers 210, 212. For use with liquid cleaning apparatus, the apparatus 40 effects removal of residual water and cleansers from the now cleaned tire in preparation for sealant application. The preheated cleaned tire is thereupon delivered by suitable means to the sealant application station.

Upon completion of the aforementioned sealant application, cure and unloading operations, each tire may be delivered to an additional heating apparatus 43, depending upon the condition of the sealant upon completion of the aforementioned operations and maintained under coaxial rotational conditions therein with respect to a series of tires using conveyor rollers 210", 212" generally similar to rollers 210, 212.

In the illustrated example, the applicator additionally maintains the tires in side-byside engagement, as shown (Figures 11, 12), except during the advancement following unloading of end tire T10. During such advancement, the remaining tires T1-T9 undulate transversely and, in effect, "walk" down the inclined rollers 210, 212 toward the unloading station. At other times, therefore, the tires define a coaxial gas passage for axial alignment with duct 224 through which evaporated solvent, if any may be extracted, discharged and/or recovered by suitable solvent recovery apparatus 226 (Figure 11). Such solvent recovery additionally may be effected with respect to heating apparatus 41, as indicated schematically.

In the illustrated example, the tire sealant or fluid air barrier is formed by a two component catalyzed sealant, the components being referenced generally in Figure 11 as sealant A and sealant B. These components are routed via separate control valves 228, 230 and manifold 232 to a mixing chamber 234 in which they are mixed immediately prior to spray application. The now mixed sealant components are then fed by a high pressure hose 235 via spray valve 236 (Figure 14A) to applicator 214 which effects airless spray application thereof.

Following application to the tire interior, the sealant is maintained in position until it gels by centrifugal force produced by tire rotation, thereby yielding a uniform coating inside the tire which does not tend to alter tire balance. The rotational velocity of the tire during such sealant application, of course should be selected to maintain the sealant in position until it gels and, in the illustrated example, the tire is therefore rotated through multiple revolutions during each spray cycle. Consequently, multiple thin coats of sealant are applied to the tire interior surfaces. Although a two component or two-part sealant is depicted in the illustrated example, it will be recognized that other appropriate sealants or liquid air barriers may be used in this invention, if desired.

In those applications in which one or both components of the sealant utilized require application of heat thereto prior to mixing or application thereof to a tire, a heat exchanger or other appropriate heating means may be provided. In the illustrated example, a tubular heat exchanger 237 of conventional design and construction is positioned adjacent the Figure 11 applicator with its output end adjacent the application station. The illustrated heat exchanger causes heat to be transferred from input steam to sealant component A in conventional fashion. Sealant component A first is delivered under pressure to the heat exchanger input indicated and, following passage through the heat exchanger, is in turn routed to valve 228, as shown (Figure 12).

In those applications requiring solvent and/ or air purge, an additional input valve 239 may be provided in communication with manifold 232 for receipt of solvent and/or air for purging the sealant system made up of the manifold 232, mixer 234, hose 234, and applicator 214, as will be described presently.

Referring now in particular to Figures 2 and 3, the cleaner includes a base structure made up of two reduced height vertical corner members 40, 42; two full-height vertical corner members 44, 46; and horizontal transverse brace members 47 therebetween. Upper and lower horizontal mounting members 49, 51 are secured between corner members 44, 46 and support a mount 48 which mounts the cleaning head 20 in the fixed position illustrated. The upper end of ramp 38 is mounted from L-shaped member 49 secured to the base structure, as shown (Figures 2, 3). The lower end of ramp 38 (not shown) is similarly supported.

Still referring to Figures 2 and 3, tire drawer 10 includes a tire supporting frame made up of vertical members 52, 54, 56, 58; upper and lower horizontal side members 60, 62; member 16; and upper horizontal end members 64, 66 respectively projecting toward one another from the upper ends of members 54 and 56, as shown (Figure 2).

End members 64, 66 terminate at sufficient transverse spacing that a tire may pass therebetween as it rolls down and off the ramp 38. The tire support frame is mounted upon lower horizontal drawer slide members 68, 70 secured to the lower ends of members 52, 54, 56 and 58, as shown (Figure 2). Horizontal V-guides 72, 74 are respectively secured by bolt connectors 76 or other appropriate means to members 68, 70. Horizontal roller mounting members 78, 80 project transversely from the aforementioned base structure and mount opposed pairs of V-type guide rollers 82 which engage and rotatively support the guide rails for horizontal reciprocative movement of the drawer.

Still referring to Figures 2 and 3, the elevator is constituted by a movable endless belt 84, the upper run of which forms a horizontal tire support surface corresponding in width approximately to the width of the tire tread, as shown (Figure 5). The belt is mounted by and is movable rotatively by two horizontally spaced guide rollers 86, 88.

The guide rollers 86, 88 are supported rotatively for rotational movement about respective transverse horizontal axes by mounting shafts 90, 92, the ends of which are mounted between two transversely spaced apart horizontal elevator support members 94 (one member not shown) by opposed pairs of pillow blocks 96. The belt 84 is driven about rollers 86, 88 by drive motor 97 which is connected with roller 86 by a drive belt 99, as shown (Figure 2). A suitable pneumatic clutch controls the driving effort applied by motor 97 to belt 84.

The elevator belt and attendant support members are movable vertically between a lowered position (Figure 7) and an elevated position (Figure 8). The support members 94 are mounted by intermediate inclined connector structure 95 from a movable carriage made up of vertical members 98, 100, 102, 104; lower horizontal members 105, 107; upper inclined members 106, 108; and connecting brace member 110 secured to structure 95. Members 105, 106, 107, 108 rotatively support appropriate V-type guide rollers 112. These rollers ride up- and down along respective vertical V-type guide rails 114, 116 which are mounted by vertical elevator slide members 118, 120 upstanding from members 78 and 80. The upper ends of members 118, 120 are secured to members 44, 46 by braces 122, 124. The belt and its attendant support members are movable vertically along guide rails 114, 116 by a double acting reciprocative actuator 126 (Figure 3) mounted vertically by the base frame underneath and connected to member 110. At the elevated position of Figure 8, the upper surface of member 110 engages and is positioned by a stationary stop 128 (Figure 2) threadably mounted by member 122, as shown (Figure 2). Stop 128 limits and, hence, effectively determines the elevated position of the elevator. In order to accommodate tires of varying sizes, this stop is adjustable vertically in order to adjust the elevated position of the elevator accordingly.

During cleaning, the tire is rotated by the drive belt at a selected rotational velocity, depending upon the type and size of the tire being cleaned. The spreader rollers, in combination with the guide rollers, maintain the tire vertical and in proper alignment with the brush during cleaning. These rollers further maintain the tire in a fixed translational position with respect to the cleaning head brush 28; yet permit the tire to rotate with respect to the brush during cleaning. The tire support surface formed by the illustrated belt construction further affords stable support for the tire in underlying relation to the point of contact of brush 28 with the tire interior surface being cleaned.

The cleaning head of this invention will now be described in further detail with reference to Figures 4 and 5. Referring first to Figure 4, the movable spreader rollers 24, 26 are supported by a scissors linkage made up of support arms 130, 132 respectively secured rotatively thereto. The upper ends of these arms are pivotally mounted adjacent the rear interior face of mount 48 be respective pins 134 and associated pivot blocks 135 secured to mount 48 by bolts 137 through slot 144 (mount associated with arm 132 not shown). Arms 130, 132 are thus movable relatively about spaced pivot points along respective substantially coincident vertical planes. The intermediate portions of these arms include elongated slots 136, 138. A pin connector 140 extends through these slots and maintains them in adjacent registry so that, when rollers 24, 26 are subjected to respective vertical forces in response to engagement with respective opposed tire beads during elevation of a tire, the rollers and their respective support arms will swing oppositely about connector 140 along respective arcuate paths, thereby spreading the tire beads toward the fully spread position illustrated in Figure 5. At this position, the guide rollers 30, 32, 34, 36 engage the upper edges of the tire beads and positively position the tire adjacent the cleaning head. These rollers are supported in pairs from the end faces of mount 48 by fixed double arm supports 142 secured to mount 48 by bolts 143 (Figure 5). To accommodate tires of varying sizes, the spreader roller support pins 134 may be secured at selected positions by adjustment of blocks 135 and bolts 137 along slots 144 (one slot not shown) in order to vary the arcuate paths travelled by rollers 24, 26, or the guide rollers may be secured at selected vertical positions along vertical slots 146 by adjustment of supports 142 and bolts 143.

The brush 28 is suspended pivotally below mount 48 to swing with respect thereto about a horizontal pivot axis substantially perpendicular to the axis of rotation of a tire adjacent the cleaning head. A motor 148 drives the brush about a rotational axis below and parallel to this pivot axis. In the illustrated example, the brush is so suspended by a double acting reciprocative actuator 150. The upper end of actuator 150 is pivotally supported from the top surface of mount 48 by a horizontal pivot shaft 152, the ends of which are supported rotatively by pillow blocks 154, 156. The actuator 150 extends vertically downward through an appropriate opening (not shown) in mount 48 and is secured to the brush motor 148.

This actuator applies a downward force to the brush for selectively controlling the brush scrubbing or contact pressure applied to the interior tire surface being cleaned.

The brush is moved arcuately about the pivot axis of shaft 152 by a double acting reciprocative actuator 158 mounted underneath mount 48 in transverse alignment with and connected to actuator 150. In the illustrated example, actuators 150 and 158 are constituted by double acting reciprocative air cylinders, and motor 148 is constituted by a reversible air motor. Actuators 150 and 158 and motor 148 are supplied with pressurized air by lines 159 (Figure 1).

Referring now to Figure 5 in particular, the brush as thus supported can be swung transversely by actuator 158 within a tire along the aforementioned arcuate path in contact with the tire interior surface at a contact pressure which is selectively controllable by appropriate operation of actuator 150. The brush is swung back and forth within the tire as depicted in Figure 5.

To this end, actuator 158 is extended and contracted in alternate sequence. A piston rod position indicator 160 (Figure 3) is mounted for conjoint movement by arm 162 with the actuator piston rod. Spaced apart sensors 164, 166 depend from mount 48 and sense the position of the indicator 160 and, in combination with the Figure 9 control system, cause the aforementioned operation of actuator 158. To control or adjust the extent of such arcuate movement of the brush, the positions of sensors, 164, 166 may be adjustable with respect to actuator 158 by securing them to mount 48 selected positions using slotted bolt attachments 168, as shown (Figure 3) -- the greater the spacing between sensors 164, 166, the greater the arc travelled by the brush, and vice versa.

In the illustrated example, the brush further is driven alternately in opposite directions of rotation, depending upon the direction in which the brush is moving within the tire. Preferably, the brush is driven in a direction of rotation which corresponds to the direction of movement of the brush within the tire so that the brush in effect "walks" along the interior tire surface. Upon completion of each transverse brush path, the limits of which are depicted in broken lines in Figure 5, the direction of brush rotation is reversed and the brush is "walked" in a reverse direction towards the opposite side of the tire.

The cleaning fluid application and removal apparatus first applies a detergent-water solution to the interior tire surface prior to initiation of the scrubbing process by brush 28. This solution suspends the material being removed from the tire interior and at the same time provides brush lubrication.

The apparatus further, upon completion of the scrubbing process, removes the now dirty solution and then automatically rinses the tire interior with fresh water. Both fluids are removed from the tire interior by vacuum application.

Referring now in particular to Figures 4 and 5, the detergent-water solution is delivered to the tire interior via a detergent addition line 170. Rinse water is delivered to the tire interior via line 172 and is applied thereto by spaced apart nozzles 174, 176 adjacent the brush. The aforementioned detergent-water solution and rinse water are stored in appropriate containers (not shown) which are connected with lines 170 and 172, respectively.

As illustrated in Figure 4, the detergentwater solution or rinse water, as the case may be, is evacuated from the tire interior via a vacuum nozzle 178 and four vacuum lines 180 (two lines not shown) which are attached to motor 148 by support 182 and mounting bolts 184 for conjoint movement with the brushes. The vacuum nozzle is positionable at appropriate vertical spacing with the tire interior surface and preferably is positioned at close clearance therewith by appropriate adjustment of the vacuum line support 182 along vertical adjustment slots 186 with respect to mounting bolts 184. In the illustrated example, therefore, the vacuum nozzle can sweep transversely inside the tire along an arcuate path generally parallel to the path of the brush 28 described previously by operating actuator 158 in a generally similar manner. During such movement of the vacuum nozzle, tire rotation is continued so that the vacuum nozzle removes fluid as it colle generally in schematic block diagram form and described hereinafter.

The Figure 9 control system includes a sequence control logic circuit which provides sequential multiple channel output signals at appropriate time intervals during the cleaning cycle, as depicted in Figure 10.

In the illustrated example, the sequence control logic circuit accomplishes one operational control cycle on a thirty (30) second basis, although the actual cycle time is some what longer than thirty (30) seconds due to a dwell time period during certain steps. In the illustrated example, the control system is semi-automatic in nature, although the system could be fully automated if desired.

In the example, therefore, the tire drawer is first withdrawn manually to its Figure 6 position and a tire is loaded thereon. The tire drawer then is advanced to its Figure 7 closed position, at which an appropriate drawer position or fault sensor produces a signal indicative that the tire drawer is closed. Following is a brief description of the channel output signal logic functions effected by the sequence control logic circuit which will be further understood with reference to Figure 10 of drawings.

Channel 1 - Fault Check: A sequence control logic circuit 190 now receives signals from the drawer position sensor, together with signals from additional system condition or fault sensors 192. Among these additional signals are signals indicative of detergent solution and rinse water supply.

The tire drawer position sensor is illustrated schematically at 192 and is illustrated in further detail in Figure 2 in which it is referenced by numeral 194. Sensor 194 responds to the proximity of probe 196 which projects from the end of the mounted drawer slide. If any of the aforementioned sensors present a fault indication, a fault logic circuit 193 is actuated in response to delivery of an appropriate logic signal from the sequence control logic circuit. The fault logic circuit in turn operates an appropriate fault indicator 200, or causes the logic circuit to proceed through a fault loop and return to channel 1 without actuation of any system components. The circuit will remain in this fault loop until the fault condition is corrected. If the fault sensors all provide a no-fault indication, the sequence control logic circuit proceeds automatically through remaining channels 2-8 in sequence.

Channel 2 - Elevator: The sequence control logic circuit now causes the elevator to be raised to its Figure 8 position by appropriate actuation of cylinder 126.

Channel 3 - Tire Position Check: The sequence control logic circuit repeats the aformentioned fault test with respect to sensor 202 (Figure 4) to determine whether a tire is in position adjacent the cleaning head. This sensor responds to the position of arm 130 and produces a signal indicative of the presence of a tire when that arm has been swung to its elevated position during spreading of the tire beads. A fault indication at this point, indicative that a tire is not in the proper position, will produce an appropriate fault indication and again cause the sequence control logic circuit to enter into its fault loop. In this instance, circuit 190 further causes the elevator to be lowered to its Figure 7 position.

Channel 4 - Belt Drive: The circuit 190 causes the drive belt to begin rotational movement by appropriate actuation of motor 97 and clutch 101.

Channel5 - Soap: The circuit 190 causes the detergent-water solution to be applied to the tire interior surface via inlet line 172 by opening valve 204. This valve controls flow of the detergent-water solution through line 172.

Channel 6 - Apply Scrub Pressure: The circuit 190 causes the brush to be engaged with the tire interior surface at a selected contact pressure by appropriate actuation of cylinder 150 and simultaneously causes the brush to begin rotating by appropriate acutation of motor 148.

Channel 7 - Scrub Cycle Start: The circuit 190 now causes the brush to begin to sweep arcuately within the tire by appropriate actuation of cylinder 158.

Channel 8 - Automatic Sequence Stop Circuit 190 thereupon stops the automatic control sequence as indicated in Figure 10. A timing control circuit 206 (Figure 9) controls the time duration of the ensuing scrub, vacuum, rinse and vacuum operations as follows. Circuit 206 causes the brush motor 97 to shut down at the end of the desired scrub time period. Thereupon, vacuum is applied to the tire interior via nozzle 178 by opening valve 208 associated therewith for a second time period in order to remove the now dirty detergent solution while cylinder 158 continues to sweep nozzle 178 transversely within the still rotating tire.

At the end of the second time period, rinse water is applied to the tire interior surface via nozzles 174, 176 by opening valve 210 associated therewith for a third time period.

At the end of the third time period, the vacuum procedure is repeated in order to remove rinse water.

Channel 9 - Fault Reset: Circuit 190 resumes sequencing upon completion of the aforementioned time operations and routes an appropriate reset logic signal to the fault logic circuit 198. The fault logic circuit alternately may be reset by curing the fault condition, or manual reset by means is now shown.

Channel 10 - Manual Sequence Stop The circuit 190 causes the elevator and the noww clean tire to be lowered to the Figure 7 position.

To adjust the Figure 9 control system for tires which require varying cleaning time, circuit 206 may be adjusted so that the four time periods determined thereby afford the desired scrub time, first vacuum time, rinse time, and second vacuum time, as the case may be.

The applicator of this invention will now be described in additional detail, first with reference to Figures 11 and 12. The applicator includes an applicator end section constituted by a supporting end frame structure made up of four vertical corner support members 238, 240, 242, 244; upper, immediate and lower transverse side members 246, 247, 248; upper, immediate and lower transverse end members 250, 251, 252; vertical end panels 254, 256; and horizontal end panel 258, as shown (Figure 11). The applicator further includes an unloading end section constituted by a second supporting end frame made up of vertical inverted U-shaped members 260, 262; and transverse side and end members 264 and 266. Longitudinal side rails 268, 270 (side rail 270 shown in Figure 15) connect the aforementioned end frame structures.

The conveyor rollers 210 and 212 are supported rotatively at their ends by respective journal blocks 272 mounted by the aforementioned end frame structures, as shown (Figures 11, 15). A variable speed drive motor 273 (Figure 11) is operatively connected by means not shown to drive roller 210 while roller 212 acts as an idler.

The rollers are of sufficient lengths to support and simultaneously rotate a predetermined number of tires, the number depending upon sealant cure or set-up time, sealant application time, tire size, type of the kicker assembly used, and other factors.

In a specific practical example, the conveyor rollers are of sufficient length to support and simultaneously rotate ten automotive tires in side-by-side contact in a clockwise direction as indicated by the arrow in Figure 11.

In this example, the conveyor rollers are driven at sufficient rotational velocity that the tires are rotated simultaneously at about 30-40 RPM. For use with a specific sealant which has a gel time of about three to four minutes and which requires the application of about sixteen coats to achieve desirable results, the spray application process with respect to a tire T1 consumes approximately thirty (30) seconds of time. Consequently, upon advancement of the T1 to the position occupied by tire T5 in the drawings, the sealant applied to tire T1 should be set-up or gelled. With continued advancement toward the unloading station, the sealant, of course, will continue to cure and should be substantially or completely cured upon arrival at the unloading station, depending upon temperature, sealant used and other factors. It will be understood, of course, that the Figure 11 applicator may be utilized with a fewer number of tires while achieving the desired result. The total number of tires which are treated simultaneously by the Figure 11 applicator, of course, should not cause an excessive force to be applied to the end tire T10 which could tend to overload the kicker assembly.

Still referring to the Figure 11 and 12, conveyor rollers 210, 212 -- in the illustrated example -- are inclined about 3 toward the unloading station with respect to horizontal, although this angle may be varied, depend- ing upon the tire size and other factors. For example, if this angle is too small, tire T1 tends to fall backwards against the spray applicator. If this angle is too large, proper alignment and positioning of the applicator 214 could be affected adversely. The roller angle further should be selected to encourage tire undulation during advancement. It will be recognized, of course, that other conveyor means could be utilized to convey the tires from the application station toward the unloading station in order to achieve desired results. For example, the conveyor rollers could be horizontal and utilized in combination with a ram device for applying a force parallel to the common tire axis in a direction toward the unloading station, or one or both rollers could be formed with appropriate auger threads for applying a force to the tires in a direction toward the unloading station, or the rollers could be positioned in divergent relationship to one another proceeding toward the unloading station. The illustrated parallel and inclined roller construction, however, is preferred in many practical applications because that construction prevents or substantially minimizes relative movement between the tires during intervals between tire unloading cycles, yet allows the tires to undulate transversely during tire advancement while preventing or substantially minimizing the likelihood that tire T1 will fall backward against the applicator.

Referring now to Figures 11 and 15, the kicker assembly includes a kicker arm 278, one end of which is supported pivotally by transverse members 277, 279 mounted between rails 268, 270 by opposed pairs of mounting members 285. 287 as shown (Figure 15). A double acting reciprocative actuator 280, preferably a double acting air cylinder, is mounted by members 281, 283 below members 277, 279 for selectively moving the kicker arm. Members 285. 287 are secured to end frame members 260. 262, by slot and pin adjustment 289 (Figure 12) which permit the kicker assembly to be secured at selected positions along the common tire axis with the kicker arm in underlying relation to tire T10. Members 285, 287 further mount a vertical backplate 274 which includes a central aperature in coaxial communication with duct 224. Duct 224 is supported by end frame members 260, 262, as shown (Figure 12). The backplate 274 rotatively mounts a plurality of support rollers 276 which are adapted to bear against the face of the adjacent end tire T10.

Consequently, the backplate, in combination with the support rollers 276, serves to fix the position of the end tire T10 with respect to the common tire axis, while permitting rotational movement thereof, in order to maintain the tires in their illustrated side-by-side engagement when rotated by rollers 210, 212. To accommodate varying numbers of tires, or tires of varying widths, or both, the positions of the kicker assembly and backplate are adjustable conjointly along the tire axis by adjustment 289 (Figure 12).

Still referring to Figure 15, the kicker arm 278 is rotatable by actuator 280 between a horizontal retracted position (depicted in solid lines) and an upright advanced position (depicted in broken lines) at which it engages and is positioned by L-shaped stop 291 mounted by members 277, 279. During movement from its retracted position toward its advanced position, arm 278 engages and lifts the T10 toward roller 212. Tire T10 thereupon rolls over roller 212 and is unloaded. If the direction of rotation of rollers 210, 212 is reversed, of course, the kicker arm should be mounted for pivotal movement about a pivot point adjacent roller 210.

The sealant applicator of this invention will now be described in detail with reference to Figures 11, 13 and 14A-14D. Referring first to Figure 11, the applicator includes a spray arm 282, the upper end of which depends from a transverse pivot member 284, the ends of which are pivotally mounted by frame members 238 and 242, respectively. A carriage assembly 286 is mounted for reciprocative movement with respect to the arm by opposed rollers 287, as shown (Figure 13). The carriage mounts a trasverse roller support arm 288 and a perpendicular nozzle support arm 290. Arm 288 mounts inclined tire positioning rollers 292 (Figure 14A). Arm 290 mounts a spray applicator 293, together with inclined spreader rollers 294, 295. The carriage assembly is movable reciprocatively with respect to arm 282 by a double acting reciprocative actuator 296 attached between member 284 and assembly 286. The arm 282 is movable pivotally in a vertical plane with respect to the supporting frame (sometimes referred to hereinafter as "sweep" movement) by a double acting reciprocative actuator 298 attached between transverse member 250 and arm 282, as shown (Figure 11). The actuators 296, 298 are generally similar and preferably are constituted by double acting air cylinders. The applicator assembly is thereby movable between a lowered advanced application position (Figure 14A), a raised advanced position (Figure 14B), a raised retracted rest position (Figure 14C), and a lowered retracted purge position (Figure 14D). In the Figure 14A, 14B positions, a U-shaped stop 299 mounted by panel 258 engages and positions the lower end of arm 282. In the Figure 14D position, the applicator 293 registers with the upper end of an inclined purge tube 300 for purposes of purging the sealant system, as will be described presently. The lower end of tube 300 is insertable within an appropriate receptacle 302 for receiving the purge and contents of the applicator via tube 300.

The spray applicator is illustrated in Figure 13 in its lowered advanced application position. In this position, the spreader rollers 294, 295 engage and spread respective sidewalls of the tire T1. The nozzle 293 is adjustably positionable by adjustable connector 304 at sufficient height from the lower interior surface of the tire in order to obtain the desired sealant distribution. In most practical applications, the nozzle is so positioned that sealant is applied heaviest adjacent the tread area with gradual feathering into the sidewalls of the tire. In the illustrated example, the nozzle effects airless spray application of liquid sealant by ejecting the sealant composition at high pressure against a deflector plate 306. The nozzle height with respect to the tire surface is therefore selected with respect to the spray pattern obtained and may be varied, depending upon tire size, in order to obtain desired sealant distribution. If the nozzle is positioned too high, for example, it tends to spray the tire sidewalls excessively so that, in order to obtain the desired sealant thickness adjacent the thread area, it is necessary to apply uneconomical amounts of sealant.

Conversely, if the nozzle is positioned too low, sealant tends to build up adjacent the center of the tread area. It will be recognized, of course, that instead of adjusting the nozzle to accommodate various tire sizes, specific nozzles could be correlated for each tire size and these nozzles substituted for one another and mounted at a corresponding fixed position with respect to the tire surface.

Referring now to Figures 14A-14D, 16 and 17, the Figure 11 spray applicator is automatically moved between the position illustrated in Figures 14A-14D by the automatic control system depicted schematically in Figures 16 and 17. Appropriate position sensors sense the position of the arm and carriage while additional sensors monitor other system conditions and produce appropriate fault indications, if necessary.

The control system additionally effects automatic purge of the sealant system if a sealant application is not effected within a predetermined time period corresponding to the sealant gel time period. The control system depicted schematically in Figure 16 is made up of conventional pneumatic and electrical components. Certain of the sensors depicted in Figure 16 are illustrated in further detail in Figures 14A-14D, with the remaining sensors and other schematically represented control system components being illustrated generally in schematic block diagram form and described hereinafter.

The Figure 16 control system includes a sequence control logic circuit which provides sequential multiple channel output signals at appropriate time intervals during the application and curing cycles, as depicted in Figure 17. In the illustrated example, the sequence control logic circuit accomplishes one operational control cycle on a thirty (30) second basis, although the actual cycle time is somewhat longer than thirty (30) seconds due to a dwell time period during sealant application. Following is a brief description of the channel output signal logic functions effected by the sequence control logic circuit which will be further understood with reference to Figure 17 ot tne drawings.

Channel 1-Fault Test: The sequence control logic circuit 306 receives signals from appropriate system condition or fault sensors 308 during the time interval 0.0-1.5 seconds of the aforementioned sequence or cycle. In the example, circuit 306 receives and processes signals from sensors responsive to steam temperature, sealant temperature, sealant supply, spray applicator carriage position, spray applicator arm position, sealant B supply, solvent recovery air flow, and tire presence. Sensors responsive to carriage position and arm position are illustrated in further detail in Figure 14A14D and are referenced respectively by numerals 310, 312. An additional sensor 315 (Figure 14a-14D) detects the presence of a fresh tire at the application station. If any of the aforementioned sensors present a fault indication, a fault logic circuit 314 is actuated in response to delivery of an appropriate logic signal from the sequence control logic circuit. The fault logic circuit in turn operates an appropriate fault indicator 316, or causes the Figure 11 sealant valves 228, 230 and actuators to be de-energized, or both. At the same time, the sequence control logic circuit initiates an idle mode whereby no further control functions are effected until the fault condition is corrected. If the fault sensors all provide a no fault indication, the sequence control logic circuit proceeds to the remaining channels in sequence.

Channel 2-Arm lit mid Down: The sequence control circuit, during the time period 6.35-9.0 seconds, repeats the aforementioned fault test with respect to sensor 310 to determine whether the spray applicator is in its lowered advanced application position of Figure 14A. A fault indication at this point, indicative that the spray applicator is at some other position, will produce an appropriate fault indication and again cause the sequence control logic circuit to assume its idle mode.

Channel 3-Oven Position Clear: The sequence control logic circuit, during the time 9.75-11.25 seconds, receives logic signals from an appropriate sensor operatively associated with the post dry oven or heat apparatus (referenced 43 in Figure 1) in order to determine whether the oven is clear to accept a tire for completion of sealant cure. If the logic signals from that sensor indicate that the oven is not clear to accept a fresh tire, the sequence control logic circuit will repeat the aforementioned fault indication and idle functions until the fault condition is corrected.

Channel 4-Start Sealant Spray: The sequence control logic circuit 306 automatically assumes its idle mode at time 7.75 seconds and will remain in its idle mode until the sealant application process is completed, in the illustrated example after about thirty (30) seconds elapsed time. The circuit 306 now routes appropriate logic signals to valves 228, 230 which thereupon are opened to admit sealant components A and B into the chamber 234 (Figure 11).

Simultaneously therewith circuit 306 routes an appropriate logic signal to 236 which, when opened, allows the now-mixed sealant components A and B to be applied in spray form to the tire, as described previously.

Channel 5-Vertical Actuation: Upon completion of the spray application cycle, circuit 306 resumes sequencing and causes the carriage to be moved from its Figure 14A position to its Figure 14B position by appropriate actuation of cylinder 296.

Channel 6-Sweep Actuaton: The circuit 306 now causes the spray applicator arm to swing from its 14B to 14C position by appropriate actuation of the sweep cylinder 298.

Channel 7-Tire Eject: During the time period 15-16 seconds, circuit 306 causes the eject cylinder 280 to move the Figure 15 kicker arm to its upright position in order to eject tire T10.

Channel 8-Fault Circuit Reset: The circuit 306 now routes an appropriate reset logic signal to the fault logic circuit 314. The fault logic circuit alternatively may be reset by curing the fault condition, or manual reset by means not shown.

Channels 9-12--Purge: The circuit 306 further effects automatic purging of the sealant system by forcing solvent and then air through the sealant fluid system mentioned previously if sealant application is not effected within a predetermined time period after completion of the previous spraying cycle. In the example, this time period is less than the sealant gel time.

Consequently, the channels 9-12 effect a purge operation only at machine shutdown or in the event of a mishap. A purge timer 318 is started each time sealant valves 228, 230 are opened and presents logic signals indicative of elapsed time from initiation of sealant application to a purge control logic circuit 320. This circuit in turn delivers appropriate logic signals to the sequence control logic circuit to effect operation of channels 9-12, as follows.

Channel 9 controls operation of the spray valve 236 (Figure 14A) by opening that valve from time period 15-24.5 seconds.

Channel 10 controls operation of the Figure 11 solvent valve 239 (Figure 11) to allow solvent flushing of the system from an appropriate supply of solvent (not shown).

Channel 11 controls operation of an air valve which delivers dry air for purging solvent from the system.

Channel 12 resets the Figure 16 control system following purge after it has been established that all system faults are corrected and that the next operational step of the process will be that of sealant application. Operation of Channel 12 further causes an appropriate reset signal to be routed to the purge timer.

WHAT WE CLAIM IS: 1. A system for producing a self-healing tyre with a self-healing sealant composition bonded to the interior of the tyre, characterised by a sealant application means located at a sealant application station for applying sealant to the interior of a tyre and tyre conveying means associated with the sealant application station for carrying a plurality of tyres in side-to-side adjacency with the their axes substantially coaxial, the tyre conveying means including means for transporting the tyre from the sealant application station to a tyre unloading station while continuously rotating the tyre about its axis from the time that sealant is applied to the tyre interior until the tyre reaches the unloading station.

2. The system of claim 1 including means for providing a clean tyre in which a sealant is to be applied, comprising means for advancing a tyre into juxtapostion with tyre cleaning means by elevating the tyre and admitting the tyre cleaning means into the tyre interior during elevation thereof, and means for rotating the elevated tyre during operation of the tyre cleaning means to clean the inner periphery of the tyre.

3. The system of claim 2 including conveyor means for transporting the tyre from the tyre cleaning means to the sealant application station and for preheating and drying the tyre during such transport.

4. The system of claim 1 wherein the tyre conveying means includes means for transporting the tyre to the sealant application station and for preheating the tyre during such transport, and means for transporting the tyre from the sealant application station and for heating the tyre during such transport.

5. A tyre sealant applicator for applying a sealant composition to the interior of a tyre and transporting the tyre from a loading station to an unloading station while continuously rotating the tyre about its axis from the time that a sealant composition is applied to the tyre interior until the tyre reaches the unloading station, which applicator comprises tyre conveyor means for carrying a plurality of tyres in side-to-side adjacency with their axes substantially coaxial from the loading station to the unloading station and for simultaneously rotating the tyres about their axes; and sealant application means for applying a sealant composition to the interior of a tyre when it is positioned at the loading station and rotated about its axis by the tyre conveyor means.

6. The applicator of claim 5, wherein the tyre conveyor means supports the plurality of tyres in side-by-side engagement when a tyre is positioned at the loading station.

7. The applicator of claim 6, comprising means located adjacent the unloading station for extracting gas from a coaxial gas passage formed by the tyres.

8. The applicator of claim 5, wherein the tyre conveyor means includes tyre support means located adjacent the unloading station for engaging and supporting a tyre positioned at the unloading station during rotational movement thereof.

9. The applicator of claim 8, comprising means for adjusting the position of the support means along the said axis.

10. The applicator of claim 9, wherein the tyre conveyor means includes a conveyor assembly operative upon the unloading means unloading a tyre from the tyre conveyor means to advance the tyres to free the loading station to accept another tyre while simultaneously maintaining rotation of the tyres.

11. The applicator of claim 5, wherein the tyre conveyor means include a conveyor assembly comprising two spaced apart elon

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. fault logic circuit alternatively may be reset by curing the fault condition, or manual reset by means not shown. Channels 9-12--Purge: The circuit 306 further effects automatic purging of the sealant system by forcing solvent and then air through the sealant fluid system mentioned previously if sealant application is not effected within a predetermined time period after completion of the previous spraying cycle. In the example, this time period is less than the sealant gel time. Consequently, the channels 9-12 effect a purge operation only at machine shutdown or in the event of a mishap. A purge timer 318 is started each time sealant valves 228, 230 are opened and presents logic signals indicative of elapsed time from initiation of sealant application to a purge control logic circuit 320. This circuit in turn delivers appropriate logic signals to the sequence control logic circuit to effect operation of channels 9-12, as follows. Channel 9 controls operation of the spray valve 236 (Figure 14A) by opening that valve from time period 15-24.5 seconds. Channel 10 controls operation of the Figure 11 solvent valve 239 (Figure 11) to allow solvent flushing of the system from an appropriate supply of solvent (not shown). Channel 11 controls operation of an air valve which delivers dry air for purging solvent from the system. Channel 12 resets the Figure 16 control system following purge after it has been established that all system faults are corrected and that the next operational step of the process will be that of sealant application. Operation of Channel 12 further causes an appropriate reset signal to be routed to the purge timer. WHAT WE CLAIM IS:

1. A system for producing a self-healing tyre with a self-healing sealant composition bonded to the interior of the tyre, characterised by a sealant application means located at a sealant application station for applying sealant to the interior of a tyre and tyre conveying means associated with the sealant application station for carrying a plurality of tyres in side-to-side adjacency with the their axes substantially coaxial, the tyre conveying means including means for transporting the tyre from the sealant application station to a tyre unloading station while continuously rotating the tyre about its axis from the time that sealant is applied to the tyre interior until the tyre reaches the unloading station.

gate rollers extending between the loading station and the unloading station for supporting the plurality of tyres in side-by-side engagement when a tyre is positioned at the loading station, and drive means for rotating at least one of the rollers to effect tyre rotation.

12. The applicator of claim 5, wherein the sealant application means include a sealant dispensing nozzle, sealant feed means for feeding sealant to the nozzle, and means for causing the nozzle and the feed means to be purged of sealant upon expiration of a predetermined time during which no sealant application is effected.

13. The applicator of claim 5, where the sealant application means includes sealant dispensing means and support means for supporting the sealant dispensing means to locate the latter into a sealant dispensing position after a tyre has been positiond at the loading station and commenced rotation about its axis.

14. The applicator of claim 13, wherein the sealant application means includes first sensor means for sensing the position of the support means, second sensor means for sensing whether a tyre has been positioned at the loading station, and control logic means operatively associated with the first and second sensor means for causing the support means to locate the sealant dispensing means at its sealant dispensing position when a tyre is positioned at the loading station.

15. The applicator of claim 13, wherein the support means include a frame, arm means pivotally mounted by the frame, carriage means mounted reciprocatively by the arm means for mounting the sealant dispensing means, means for pivotally moving the arm means with respect to the frame, and means for reciprocatively moving the carriage means with respect to the arm means.

16. A tyre sealant application method which comprises : positioning a tyre at a loading station; continuously rotating the tyre about its axis; applying a sealant composition to the interior of the tyre when positioned at the loading station during rotation thereof; and moving the tyre in an axial direction from the loading station toward an unloading station while continuing to rotate the tyre about its axis from the time that the sealant applying step is completed until the tyre reaches the unloading station, the tyre being moved axially upon completion of the sealant applying step a distance sufficient to clear the loading station to accept a fresh tyre; positioning a fresh tyre at the loading station following such axial tyre movement; and continuously rotating the tyres, including the fresh tyre, and applying a sealant composition to the interior of the fresh tyre when positioned at the loading station during rotation of the tyres.

17. The method of claim 16, including supporting the tyres in side-by-side engagement when a tyre is positioned at the loading station.

18. The method of claim 17, comprising the step of extracting gas from a gas passage formed by the tyres.

19. A method for producing tyres having a sealant composition applied to the interior surface of each tyre, the method comprising: applying a fluid sealant composition to the interior surface of a tyre while rotating the tyre to ensure even application of sealant; and conveying the tyre during a subsequent processing step in an axial direction while simultaneously rotating the tyre about its axis during a portion of the processing of the sealant composition to minimize flow of the sealant composition, the step of conveying the tyre in an axial direction including moving the tyre in sideto-side adjacency with at least one other tyre while simultaneously rotating the other tyre about its axis.

20. The method of claim 19, comprising the step of extracting gas from a gas passage through the tyres while rotating them about their axes.

21. A system for producing a selfhealing tyre the system being substantially as herein described and shown in the drawings.

22. A tyre sealant applicator constructed and arranged substantially as herein described and shown in the drawings.

23. A tyre sealant application method substantially as herein described with reference to the drawings.