Background of the Invention
1. Field of the Invention
This invention relates generally to cable connectors for electrical storage batteries, and more particularly to clamps used with such connectors.
2. Description of the Prior Art
The connector clamps of the prior art, as typified for example by those shown in U.S. Pat. Nos. 3,694,798 (Julian) and 3,936,134 (Piscionere), rely on the tightening of a nut on the threaded shank of a bolt to ensure lateral contact between the terminal of an electric storage battery and the laterally constrictable ears of the cable connector. However, several difficulties are associated with such arrangements. First, hand tools are required to disconnect the clamp, and such tools are not always readily available under emergency conditions, for example when the battery fails and requires replacement. Secondly, the terminal, connector and associated clamp elements are prone to chemical corrosion. Nuts and bolt heads are gradually eaten away, with the result that when wrenches are applied thereto, surfaces break off, making it difficult to loosen the bolts. These difficulties often translates into impossibility, at which point the bolts must be cut before clamp can be loosened and the connector removed from the terminal.
Summary of the Invention
The object of the present invention is to provide a connector clamp which may be released quickly, without having to employ wrenches or other like hand tools, and without regard to corrosive damage, if any, to the connector and/or clamp components.
A companion object of the present invention is the provision of a clamp which effectively ensures contact between the laterally constrictable ears of the cable connector and the battery terminal, again without having to resort to the use of hand tools.
These and other objects and advantages are achieved with a preferred embodiment of the invention to be described hereinafter in more detail with reference to the accompanying drawings, wherein:
Description of the Drawings
FIG. 1 is a top plan view, with portions broken away, of a cable connector together with quick release clamp in accordance with the present invention; and
FIG. 2 is a sectional view on an enlarged scale taken on line 2--2 of FIG. 1.
Detailed Description of Preferred Embodiment
Referring now to the drawings, one portion of conventional electric storage battery 10 is shown with a terminal 12 protruding vertically therefrom. A cable 14 is connected to the terminal by means of a cable connector 16 which includes a somewhat semicylindrical base portion 16a with integrally formed ears 16b, 16c extending in a generally parallel relationship therefrom. The ears 16b, 16c are spaced one from the other at 18 and are provided with mutually aligned holes 20. The ears 16b, 16c are laterally constrictable around and against the terminal 12 to electrically connect the cable 14 to the battery.
This lateral constriction is achieved by the clamp of the present invention, which includes a bolt 22 having a threaded shank 22a terminating at one end in an enlarged hexagonal head 22b. The shank 22a is dimensioned to extend through the aligned holes 20 in the ears 16c, 16c, with the head 22b being located on the outermost side of the ear 16b. The bolt 22 has a slit 24 extending axially through the head 22b into the shank 22a.
A cam lever 26 is received in the slit 24 and is rotatably connected to the bolt 22 by means of a pin 28 extending across the slit in a direction transverse to the longitudinal bolt axis. The cam lever has a cam surface 30 lying on a reference circle (not shown) whose center 32 is offset by a distance "d" with respect to the axis of the pin 28.
A pressure washer 34 is axially received on the bolt shank 22a at a location between the bolt head 22b and the outermost side of ear 16b. At least one and preferably both sides of washer 24 are countersunk. Either countersunk side of the washer can coact in engagement with the cam surface 30 of lever 26.
The cam lever 26 is rotatably adjustable about the axis of pin 28 between a "closed" position illustrated by the solid lines in the drawings, and an "open" position indicated by the dot-dash lines in FIG. 1. A nut 36 is threaded onto the shank 22a on the outermost side of ear 16c. When initially installing the clamp, the nut is merely hand-tightened to bring the pressure washer 34 lightly against the outermost surface of ear 16b and the nut lightly against the outermost surface of ear 16, with the cam lever 26 being adjusted to its open position. At this adjustment, the ears 16b, 16c are not being urged together to narrow the gap 18, thus allowing the connector to be easily placed onto or removed from the terminal 12.
Preferably, the bolt 22, lever 26, pin 28, washer 34 and nut 36 are stainless steel in order to minimize corrosion. When the cam lever is adjusted to the closed position, the cam surface 30 engages the adjacent countersunk side of the pressure washer 34, thereby pulling the bolt 22 through the pressure washer to the left as viewed in FIG. 2. This also pulls the nut 36 in the same direction, with the result that the pressure washer 34 and nut 36 act on their respectively adjacent ear surfaces to laterally constrict the ears 16b, 16c against and around the battery terminal. The net result is a secure clamping of the connector to the battery terminal, without having to resort to the use of hand tools. Should it become necessary to remove the connector from the terminal, one need only rotate the cam lever 26 to its open position. This relieves the constraining force on the ears 16b, 16c to an extent sufficient to allow the connector to be pulled off of the terminal. This can be accomplished in a rapid quick-disconnect manner without the use of hand tools, and despite any corrosion that might have taken place.