Method of dispensing metered portions of molten lead

A method of dispensing metered portions of molten lead comprises the steps of providing a heater body with a lead reservoir that produces sufficient heat to form molten lead and providing a lead dispensing shuttle plate with at least two lead metered cavities that are filled with molten lead in a fill position. The heater body is movable between a dispense position and a feed position. At least one of the metered cavities releases the molten lead when the heater body is moved to the dispense position. In one aspect, the method comprises supplying a strip of lead so that when the heater body moves to the feed position, it receives a portion of the strip of lead. In another aspect, the method comprises injecting inert gas over the lead reservoir and into the dispensing metered cavity to prevent air from entering the metered cavity.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to assembling lead acid batteries and more specifically to a battery assembling method which produces lead acid batteries which have many improvements over the prior art.

2. Discussion of the Prior Art

A present problem of lead acid battery manufacture is the rapid oxidation of molten lead which is exposed to the atmosphere when it is heated above the 625 degrees Fahrenheit melting point. The problem is greatly compounded when molten lead exposed to the atmosphere is further heated to nearly 1000 degrees Fahrenheit. Plate lugs of the battery cells enter such dispensed high temperature molten lead and fuse with it, the lugs further act as heat sinks for cooling the dispensed lead. At such elevated temperatures substantial drossing can occur which is wasteful, expensive, abrasive, clogging and toxic.

Accordingly, there is a clearly felt need in the art for a battery assembling machine which does not expose molten lead to the atmosphere, thus preventing drossing of the molten lead.

OBJECTS OF THE INVENTION

Accordingly, it is an object of the present invention to provide a battery assembling method which reduces the amount of equipment and manpower required.

It is a further object of the present invention to provide a battery assembling method which is rapid, efficient and relatively inexpensive.

It is yet a further object of the present invention to provide a battery assembling method which seals, but does not expose molten lead to the atmosphere, thus preventing drossing of the molten lead.

It is yet a further object of the present invention to provide a battery assembling method which does not require venting of an open lead pot.

It is yet a further object of the present invention to provide a battery assembling method which does not require lead to be pumped and a pumping device to be maintained.

Finally, it is another object of the present invention to provide a battery assembling method which does not require a large quantity of lead to be maintained at a molten temperature with the associated energy costs.

SUMMARY OF THE INVENTION

The present invention provides a battery assembling method which is more efficient than that of the prior art. The battery assembling method includes a lead dispenser/heater unit, cover positioner, container positioner, and lead feeder. A battery container with battery plates contained therein is initially retained by a horizontal container positioner.

Lug preparation is not required when utilizing some types of lead alloys. If needed, the lug preparation area includes at least one heating station. The lug preparation area may also include at least one fluxing station, and at least one tinning station. The inclusion of the fluxing and tinning stations is dependent upon the condition of the plate lugs of the battery, before insertion into the battery assembling device. The lug preparation area disclosed in this application is given by way of example and not by way of limitation. A lug preparation area may include any combination or order of the above disclosed stations.

The horizontal container positioner indexes the battery container over the lug heating station and the lugs of the battery plates are heated before fluxing. The horizontal container positioner then indexes the battery container over the fluxing station and flux is applied to the lugs of the battery plates. The horizontal container positioner next indexes the battery container over the tinning station and the lugs are tinned with solder.

The horizontal container positioner finally indexes the battery container over the lead dispenser/heater unit. The container positioner grips the battery container and the horizontal container positioner releases its grip on the battery container. The lead dispenser/heater unit includes a container heating platen, a cover heating platen, a heater body, a lead dispensing shuttle plate, a lead reservoir and an inert gas cavity. The container heating platen is disposed on a top of the heater body and the cover heating platen is disposed on a bottom thereof. The lead reservoir is disposed in a top of the heater body. A strip opening is formed in a lead reservoir cover plate which is attached to a top of the heater body above the lead reservoir. The inert gas cavity is disposed above the lead reservoir. The inert gas cavity is filled with inert gas from a supply tank. The inert gas displaces and prevents regular air from entering the lead reservoir and drossing the molten lead.

The lead dispensing shuttle plate is disposed in a middle of the heater body. The lead dispensing shuttle plate includes at least two lead metered cavities for dispensing molten lead which forms plate straps and terminals in the battery cover. The lead dispensing shuttle plate has a fill position for retaining molten lead and a dispense position for dispensing molten lead into the battery cover.

The container positioner lowers the battery container such that an edge of an open end thereof contacts a container heating platen and the cover positioner raises the battery cover such that an edge of an open end contacts the cover heating platen. The lead dispensing shuttle plate is slid into a dispense position to direct molten lead into plate strap mold wells in the battery cover and into terminal molds to form plate straps and terminals. A dispenser actuator pulls the lead dispenser/heating unit back such that the strip opening aligns with a lead strip of the lead feeder. The lead that was dispensed for previous battery is replaced with new lead from the lead feeder.

As the dispenser actuator pulls the combination lead dispenser/heating unit, the container positioner is lowered and the cover positioner raised such that the edge of the open end of the battery container is attached to the edge of the open end of the battery cover. The container and cover heating platens heat the open end of the container and the open end of the cover such that the cover may be sealed to the container. Once the lead in plate straps and terminals solidify, the battery is grasped by a conveyer gripper and aligned with a conveyor by a conveyer actuator. A vertical conveyer actuator is raised to meet the battery. The conveyer gripper is released and the conveyer transports the completed battery to an external location. The battery assembling method is capable of producing batteries disclosed in U.S. Pat. Nos. 5,885,731 and 6,059,848.

DETAILED DESCRIPTION OF THE INVENTION

With reference now to the drawings, and particularly toFIG. 1, there is shown a cross sectional view of a battery assembling method. With reference toFIGS. 2–14, the battery assembling method includes a lead dispenser/heater unit12, cover positioner14, container positioner16, and lead feeder18. A first battery container200with battery plates202contained therein is retained by a horizontal container positioner20. The horizontal container positioner20includes a horizontal container actuator21and gripper fingers23. The above items are preferably retained in some type of frame22.

A lug preparation area10is not required when utilizing some types of lead alloys. If needed, the lug preparation area includes at least one heating station24. The at least one heating station24preferably includes a heating actuation device26, a mounting plate28, and at least one heating element30. Preferably, an inductive heating element is used, but other types of heating devices may also be used. The lug preparation area10may also include at least one fluxing station, and at least one tinning station. The inclusion of the fluxing and tinning stations is dependent upon the condition of the plate lugs of the battery and the lead alloy used in the battery, before insertion into the battery assembling device1.

The lug preparation area10disclosed in this application is given by way of example and not by way of limitation. A lug preparation area may include any combination or order of the above disclosed stations. As disclosed by example in this application, a lug actuator32is used to provide vertical movement to a lug plate34. A fluxing pan36is attached to a top of the lug plate34and contains a quantity of flux204. A tinning pan38is attached to a top of the lug plate34and contains a quantity of molten solder206. At least one heater element40is used to maintain the solder at a molten temperature. The container positioner16includes a container actuator17and container gripping fingers19which are attached to a moving end of the container actuator17.

With reference toFIG. 2, the lead dispenser/heater unit12includes a heater body42, a container heating platen44, a cover heating platen46, a lead dispensing shuttle plate48, and a dispenser actuator50. The container heating platen44is attached to a top of the heater body42with a cover insulator52inserted therebetween. The lead dispensing shuttle plate48preferably includes a top plate49and a bottom plate51. At least two lead entrance openings53are formed through the top plate49. At least two lead metered cavities55are formed in the lead dispensing shuttle plate48in line with the at least two lead entrance openings53. A lead exit opening57is formed through a bottom of each lead metered cavity55. A shuttle slot54is formed in a bottom of the heater body42. The shuttle slot54is sized to slidably receive the lead dispensing shuttle plate48.

A shuttle retention plate56retains the lead dispensing shuttle plate48under spring force. At least two spring loaded bolts58force a top of the shuttle retention plate56against a bottom of the lead dispensing shuttle plate48and a top of the lead dispensing shuttle plate48against a top of the shuttle slot54. The force fit between the top and bottom of the lead dispensing shuttle plate48is required to prevent molten lead from leaving the lead metered cavities55and smearing on the top or bottom of the lead dispensing shuttle plate48. The cover heating platen46is attached to a bottom of the shuttle retention plate56with a container insulator60inserted therebetween. The container and cover insulators allow the container and cover heating platens to be maintained at a different temperature than the heater body42.

A lead reservoir cover plate62covers a top of a lead reservoir64formed in a top of the heater body42. A lead strip opening66is formed through the lead reservoir cover plate62, adjacent the lead reservoir64. A lead passage65is formed adjacent the lead reservoir64. At least one lead cross passage67is formed adjacent the lead passage65. At least two lead feed openings69are supplied with molten lead210from the lead passage65or at least one lead cross passage67. An inert gas reservoir passage68is formed over the lead reservoir64. The inert gas reservoir passage68receives inert gas through an inlet pipe70. An inert gas tank72supplies the inert gas208. The inert gas208prevents drossing of the molten lead210in the lead reservoir64. An inert gas passage71is formed in a bottom of the container heater platen44. At least two inert gas passage openings74are formed through the container insulator52and the heater body42. A shuttle actuator76is used to slide the lead dispensing shuttle plate48from a fill position to a dispensing position. An end of the shuttle plate48is attached to a moving end of the shuttle actuator76.

At least two lead dispense openings78are formed through the shuttle retention plate56, container insulator60, and cover heating platen46in line with the at least two lead metered cavities55when in a dispense position. Preferably, a lead dispense bushing80is formed partially through the shuttle retention plate56, and through the container insulator60, and cover heating platen46. When the lead dispensing shuttle plate48is in a dispense position inert gas flows behind the molten lead210through the lead dispense openings78.

The inert gas208prevents air from entering through the at least two lead dispense openings78until the lead dispensing shuttle plate48is moved to a fill position. The inert gas208bubbles through the molten lead210to the inert gas reservoir passage68as the at least two lead metered cavities55are filled with molten lead210. If air were allowed to fill the at least two lead metered cavities78, the air would dross the molten lead210.

At least two container heaters82are formed in the container heating platen44. At least two cover heaters84are formed in the cover heating platen46. At least two retainer heaters86are formed in the shuttle retention plate56. At least two body heaters88are formed in the heater body42. A plurality of lug clearance openings90are formed in a top of the container heating platen44.

With reference toFIG. 1, the cover positioner14includes a cover base92, a cover actuator93, a mold actuator94, and at least two terminal molds96. A bottom of the cover base92is attached to a moving end of the cover actuator93. The cover actuator93provides vertical motion to the cover base92. A cover cavity98is formed on a top of the cover base92to receive the battery cover212.

A retainer plate100is attached to a moving end of the mold actuator94. Terminal cavity102is formed in a top of each terminal mold96. Each terminal mold96is slidably retained on a slide rod106and urged upward with a spring104. The retainer plate100restricts the upward movement of the terminal mold96. At least one liquid coolant path108and at least one mold heater109are formed in the body of each terminal mold96.

Gripper fingers110extend from a moving end of a conveyor actuator112. A battery conveyor114includes a vertical conveyor actuator116, stationary conveyor base118, moveable conveyor section120, and a coolant spray122. The moveable conveyor section120is attached to a moving end of the vertical conveyor actuator116. The coolant spray122is attached to a bottom of the moveable conveyor section120.

The battery assembling method preferably operates in the following manner. With reference toFIG. 1, if the lug preparation area10is required, the horizontal container positioner20indexes the battery container200over the lug heating station24and the lugs209of the battery plates202are heated before fluxing by the at least one heating element30. With reference toFIG. 5, the horizontal container positioner20then indexes the battery container200over the fluxing pan36. With reference toFIG. 6, the lug actuator32raises the fluxing pan36to coat the lugs209with flux204. With reference toFIGS. 7 and 8, the lug actuator32lowers the fluxing pan36so that the horizontal container positioner20may index the battery container200over the tinning pan38. With reference toFIG. 9, the lug actuator32raises the tinning pan38to tin the lugs209with solder206. With reference toFIGS. 11 and 12, the lug actuator32lowers the tinning pan38and the horizontal container positioner20indexes the battery container200over the lead dispenser/heater unit12.

The container gripping fingers19grasp the battery container200and then the gripping fingers23release thereof. With reference toFIG. 3, the container actuator17lowers the battery container200such that an edge of an open end thereof contacts a heating surface45of the container heating platen44. The cover actuator93raises the battery cover212such that an edge of an open end contacts the heating surface47of the cover heating platen46. With reference toFIG. 4, the mold actuator94raises the retainer plate100such that the at least two terminal molds96rise to contact terminal openings in the battery cover212. Each terminal mold96is heated with the heater109. With reference toFIG. 5, the lead dispensing shuttle plate48is slid into a dispense position by the shuttle actuator76. The molten lead210descends through the lead exit openings57, the openings in the shuttle retaining plate56, and the lead bushings80. The molten lead drops into plate strap mold wells in the battery cover212and the terminal molds96form plate straps and terminals.

After the molten lead has filled the plate strap mold wells and terminal molds96, the shuttle actuator76pulls the dispensing shuttle plate48back to the fill position. With reference toFIG. 9, the dispenser actuator50pulls the lead dispenser/heater unit12back such that the strip opening66aligns with a lead strip124of the lead feeder18. The lead210that was dispensed for previous battery is replaced with new lead from the lead feeder18. With reference toFIG. 8, the battery container201is raised and the battery cover212lowered and the lead dispenser/heater unit12pulled toward the lead feeder18.

With reference toFIG. 10, after the lead dispenser/heater unit12is cleared away, the battery container201is lowered and the battery cover212raised such that the edge of the open end of the battery container201is attached to the edge of the open end of the battery cover212. The container and cover edge heating platens heat the open ends of the battery container and cover such that the battery cover212may be sealed to the battery container201. The at least two plate straps and terminals are substantially simultaneously cast as the battery cover is sealed to the battery container.

The mold heater109is turned-off and coolant is run through the at least one coolant path108. With reference toFIG. 13, once the lead in plate straps and terminals solidify, the assembled battery214is grasped by the conveyer gripper110and aligned with the conveyor114by a conveyer actuator112. The moveable conveyor section120is raised by the vertical conveyer actuator116to meet the assembled battery214. The assembled battery214is sprayed with coolant123from a coolant spray device122. With reference toFIG. 14, the conveyer gripper110is released and the moveable conveyor section120lowers the assembled battery214even with the stationary conveyor base118. The conveyer114transports the assembled battery214to an external location where the assembled battery214is ready to be filled with electrolyte.