US2375406A

US2375406A - Nonoverfill device

Info

Publication number: US2375406A
Application number: US444643A
Authority: US
Inventors: Lyle L Drown
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1942-05-27
Filing date: 1942-05-27
Publication date: 1945-05-08
Anticipated expiration: 1962-05-08

Description

May 8,, 1945. L. L. DRQWN Y NONOVERFILL DEVICE Filed May 27, 1942 wh/d wf $55 3 16;, ATTORNEYS.

Patented May 8, 1945 N ONOVERFILL DEVICE Lyle L. Drown, Iietroit, Mich., assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Application May 27, 1942, semi: No. 444,643

1 Claim.

This invention relates to improvement in nonoverfill devices for storage batteries and other electrolytic cells, and is especially useful in stor-, age batteries for 'automobileuse.

The primary object of the invention is to provide simple and reliable and inexpensive'means for automatically closing the filling opening when the plug is removed to permit the cell to be filled only to the required level .and insuring an adestorage battery electrolyte and said ball be forced through a restricted opening in the filler opening and expand to its normal size after it passesthrough the opening and adapted, when the vent plug is removed and the electrolyte level is raised 34 about the filler opening,

normally covered by electrolyte, the normal level of which is indicated at 23. The cell is provided with the usual internal shoulders, not shown, upon which rest a cell cover 24. The joint between the cell and cover is sealed with the usual sealing compound, not shown.

The cover in the present'instance is shown as having a filler opening having a boss 3| above the surface of the cover which is preferably internally threaded as at 32 for engagement with external threads of a vent cap 33. The cover 24 is formed to provide a tubular extension or skirt This tubular extension projects downwardly to a predetermined distance, but spacedfrom the top edges of the plates of the plate assembly 2|. The tubular extension 34' is provided with an internal ledge 35 defining a restricted opening 36. The under surface of the ledge serves as a valve seat for a floating ball 3l.. The ball is'made of any suitable substance capable. of floating, and resistant to the storage battery electrolyte. It may be made,

' for example, of soft rubber or other soft material.

to the proper level, to engage a seat and close.

the restricted opening. When the vent plugis attached to the cover the plug forces the floating panying drawing wherein a preferred embodiment of the present invention is clearly shown.

In the drawing: I Fig. l is a fragmentary sectional view of a cell cover showing a, floating rubber ball valve held in a closed position by the liquid, the filler plug or cap being removed.

Fig. 2 is a view similar to Fig. 1 but showing a vent plu screwed downinto its well for closing the latter.

The material should be such as to yield sufficiently to seal a seat when the electrolyte level in the cell has been reached so that the liquid will rise rapidly in the filling opening above the ball to give a signal to the operator that the filling opdimensions of the restricted opening 36 so as to provide for a sealing fit therebetween and the cross-dimensions of the ball are less than the cross dimensions of the tubular extension 31 so as to provide for considerable play of the ball within the confines of the tubular extension below the seat. When liquid is poured into the cell the electrolyte level will rise until the ball engages the seat to seal the restricted opening 36.

This ball together with the film-generally formed on the surface of the ball will seal the restricted opening that airwill be trapped below the seat and the level and also in the space exterior of the tubular extension and the underside of the Fig. 3 is a. fragmentary sectional view showing cover above the electrolyte level. I

The rubber ball is preferably assembled with thc'ell after all of the other elements ofthe cell have been assembled and sealed. The ball is first inserted into the filler opening and-rests upon the upper side of the ledge 35. The ball is then manner 'illustrated in Fig. 3.

forced through the opening by a tool 40 in the served that the upper surface 4| of the ledge 35 which merges with the walls of the restricted opening is rounded as at 42 in order to facilitate the forcing of the ball through the opening and also to prevent the ball from being marred while. it is being forced through the opening 36.

When the ball passes through the opening the ball will expand to its normal size due to itsown resiliency and occupy the space between the'seat and the upper edges of the plates of the plate: assembly 2| which extend across the lower end of the tubular extension. It will be observed that the space between the lower edge of the tubular extension is considerably less than the cross dimensions of the ball, thus the ball cannot pass from the confines of the tubular extension should the level of the liquid drop below the up-, per-edges of the plates 2 I. The ball in that case would rest upon the plates as indicated by the dot-and-dash circle in Fig. l. The lower edge of the ledge is preferably formed with tapered or cup-shaped surface 45, said surface acting as .a guide to direct positively the ball 3'! over the opening 36 as the electrolyte level rises, thus insuring that the opening 36 will be sealed by the ball float valve when the desired electrolyte level has been reached.

The ball is moved away from the seat by the vent plug 33 having an extension 46 adapted to project through the restricted opening 36 and engage the ball 3! forcing same downwardly into the electrolyte, as'in Fig. 3, and maintain same away from the seat permitting the trapped air and also gases to pass through the by-pass passages 38 and through the restricted opening 36 and thence through a duct 42 in the vvent plug 30 to the-atmosphere, i .It will be seen that the present structure is extremely simple and inexpensive. Further it simplifies the assembly and charging procedure at the factory in that the ball valve can be left It will be obas herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows: In combination with a container for liquid and including plates normally covered by the liquid;

a cover having a filling opening adapted to receive and retain a vent plug, said cover having a skirt depending therefrom about the filling opening and extending below the normal liquid level with the lower end thereof spaced from the plates, said skirt having an inwardly extending a rib defining an annular opening smaller than the out until the battery is complete and ready for shipment if so desired.

While the embodiment of the present invention skirt at a point above the normal liquid level, said rib joining the skirt with frusto-conical 'sur-' faces said skirt having a by-pass above the liquid level and below the smaller opening providing communication between the space outside the skirt and the space within the skirt above the level but below the smaller opening; a valve normally floating on the surface of the liquid and guided by the lower conical surface of the rib to seal the smaller opening to prevent communication from the space below the rib to outside atmosphere when the plug is removed and the liquid is at its normal level, said valve comprising a soft rubber ball having a cross dimension larger than the smaller opening and also the space between the lower edge of the skirt and. the 7 plates and adapted to be forced through the smaller opening under distortion and then expand to normal size below the rib and float on the liquid within the confines of the skirt, said ball contacting the upper conical surface of the .rib to facilitate distortion of the ball when same is being forced through the smaller opening; and a readily attachable and detachable vent plug having an extension projecting loosely through the smaller opening when the p u i attached d moving the ball into the liquid to open the smaller opening to establish communication between the spaces above'and below the rib and the atmosphere through the vent plug.

LYLE L. DROWN.