Connection structure and connection fitting for an electrode post of a battery

An electrode post connection structure for connecting a connection conductor to an electrode post of a battery through a connection fitting, which includes a lock stage portion formed on a circumference of the electrode post, a tapered portion formed at a top portion of the electrode post, a lock spring inserted in the connection fitting so as to engage with the lock stage portion to thereby lock the electrode post and the connection fitting with each other, and a hollow elastic body accommodated in the connection fitting so as to press the connection conductor to thereby connect the electrode post and the connection conductor to each other. Thus, work for connecting a connection conductor to an electrode post of a battery is simplified, and the electric characteristic and reliability of the connection are improved greatly.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an electrode post connection structure and 
a fitting thereof when an electric conductor is connected to an electrode 
post of a battery. 
2. Background 
Conventionally, when two batteries or more are to be connected to each 
other, a plate-like connection terminal c is interposed between electrode 
posts b and b' of two batteries a and a' and fastened to the electrode 
posts b and b' by a device of nuts d and d' respectively, for example, as 
shown in FIG. 12 as disclosed in Unexamined Japanese Patent Publication 
No. Hei. 6-140020. 
In this conventional connection structure, however, there is a problem that 
since it is necessary to perform such troublesome work to fit and fasten 
the nuts d and d' onto the electrode posts b and b' respectively in 
connecting operation, considerably much labor and long time are required 
in the case of connecting a large number of batteries to each other so 
that the productivity is remarkably reduced. 
SUMMARY OF THE INVENTION 
In view of the foregoing problem, it is an object of the present invention 
to provide an electrode post connection structure and a connection fitting 
thereof, in which a work for connecting a connection conductor to an 
electrode post of a battery is simplified, and an electric characteristic 
and reliability of the connection are improved greatly. 
In order to achieve the above object, according to a first aspect of the 
present invention, an electrode post connection structure for connecting a 
connection conductor to an electrode post of a battery through a 
connection fitting, includes a lock stage portion formed on a 
circumference of the electrode post, a tapered portion formed at a top 
portion of the electrode post, a lock spring inserted in the connection 
fitting so as to engage with the lock stage portion to thereby lock the 
electrode post and the connection fitting with each other, and a hollow 
elastic body accommodated in the connection fitting so as to press the 
connection conductor to thereby connect the electrode post and the 
connection conductor to each other. 
In the above electrode post connection structure, preferably, the hollow 
elastic body is a coil spring. 
According to a second aspect of the present invention, an electrode post 
connection fitting includes a fitting cylinder having an electrode 
insertion hole formed in its bottom wall, lock windows formed in its head 
portion, and a conductor insertion opening formed in its circumferential; 
a flexible hollow elastic body accommodated in the fitting cylinder; and a 
lock spring having openable/closable grasping arms; an unlock button 
having spring holding portions provided with guide slopes respectively, 
the lock spring being inserted into the lock windows so as to be mounted 
on the spring holding portions of the unlock button to thereby movably 
support the unlock button. 
In the above electrode post connection fitting, preferably, the hollow 
elastic body is a coil spring. 
In the above electrode post connection fitting, preferably, an outside of 
the fitting cylinder is covered with an insulation cover having an 
operation hole. 
According to the present invention, the lock spring is made to engage with 
the lock stage portion of the electrode post by only one step of operation 
to fit the cylinder of the connection fitting onto the electrode post. 
Further, unlock of the cylinder from the electrode post can be performed 
also by only one step of operation to push the unlock button. 
Consequently, the connection and separation work is simplified so that the 
workability can be remarkably improved in the case of connecting a large 
number of batteries to each other. 
Moreover, the connection conductor is normally urged against the electrode 
post by the device of the hollow elastic body such as a coil spring, or 
the like, accommodated in the cylinder and, therefore, the electric 
connection can be surely performed to thereby is obtain high reliability.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
FIG. 1 is a vertical sectional view showing an electrode post connection 
fitting A according to a first embodiment of the present invention, and 
FIG. 2 is a front view showing an electrode post B. 
The electrode post connection fitting A includes a fitting cylinder 1 made 
of a thin conductive metal plate, a coil spring 2 which is a hollow 
elastic body accommodated in the fitting cylinder 1, a lock spring 3 
formed from elastic metal wire through bending work, an unlock button 4 of 
synthetic resin, and an insulation cover 5 applied to the outside of the 
fitting cylinder 1. 
The electrode post B includes a cylindrical electrode base 6 mounted on a 
battery. The cylindrical electrode base 6 has a top portion 6a, a tapered 
portion 6b formed on a circumference of the top portion 6a of the 
electrode base 6, a lock stage portion 6c formed in the vicinity of and 
under the tapered portion 6b, and a connection portion 6e formed at a base 
portion 6d so as to come into contact with a connection conductor such as 
a bus bar or the like. 
In the fitting cylinder 1 of the electrode post connection fitting A, a 
head portion 1a is reduced in diameter and an electrode fitting opening 7 
which is to be fitted onto the electrode post B is formed in a bottom wall 
1b. The head portion 1a is provided for accommodating the top portion 6a 
of the electrode post B, and has, at its opposite sides, a pair of lock 
windows 8 through which the lock spring 3 is inserted. A conductor 
insertion opening 9 is formed in a portion of a peripheral wall 1c at a 
position in the vicinity of the bottom wall 1b so as to communicate with 
the electrode fitting opening 7 as shown also in FIG. 3. 
The lock spring 3 is made from metal wire which is bent at its center 
portion to form a pair of openable/closable grasping arms 10 and 10 which 
extend to the opposite end portions as shown in FIG. 4. 
The unlock button 4 has a supporting wall 11 for covering the head portion 
1a of the fitting cylinder 1, and spring holding portions 12 and 12 formed 
in the lower end portion of the supporting wall 11 so as to have guide 
slopes 12a and 12a which are formed by cutting opposite edges of the 
supporting wall 11. 
The unlock button 4 is supported in such a manner that the respective 
grasping arms 10 and 10 of the lock spring 3 are inserted through the lock 
windows 8 and 8 located at the opposite sides of the fitting cylinder 1 
and the respective spring holding portions 12 and 12 of the unlock button 
4 are grasped between end portions 10a and 10a of the grasping arms 10 and 
10. 
The insulation cover 5 is formed through molding with a synthetic resin 
material so as to have a cylindrical shape. An operation hole 5a is opened 
in a top portion of the insulation cover 5 so that the unlock button 4 can 
be pushed through the operation hole 5a. 
Next, description will be made as to the operations of the above parts when 
the foregoing electrode post connection fitting A is to be fitted onto the 
electrode post B of the battery. 
First, the connection conductor 13 is inserted into the conductor insertion 
opening 9 of the electrode post connection fitting A so that the 
connection conductor 13 is slightly pressed by the coil spring 2 so as to 
be held between the bottom wall 1b of the fitting cylinder 1 and the coil 
spring 2. 
When the electrode fitting opening 7 of the electrode post connection 
fitting A is fitted and pressed onto the top portion 6a of the electrode 
base 6 of the electrode post B, the top portion 6a of the electrode base 6 
is inserted into the head portion 1a of the fitting cylinder 1 while 
compressing the coil spring 2. When the insertion onto the electrode post 
B is advanced, the lock spring 3 abuts on the tapered portion 6b of the 
electrode base 6 so that the grasping arms 10 and 10 of the lock spring 3 
are mutually opened along the tapered portion 6b and led into the lock 
stage portion 6c of the electrode base 6. As a result, the fitting 
cylinder 1 is locked to the electrode base 6 as shown in FIG. 5. 
At this time, the connection portion 6e of the electrode base 6 and the 
connection conductor 13 are electrically surely connected to each other 
because both of them are urged against each other by the coil spring 2. 
FIG. 6 is a perspective view showing the exterior of batteries 14 and 14' 
which are connected to each other through the electrode post connection 
fitting A. 
When the electrode post connection fitting A is to be separated from the 
electrode post B, the unlock button 4 is pushed through the operation hole 
5a of the insulation cover 5 as shown by an arrow in FIG. 7. 
When the unlock button 4 is pushed, the supporting wall 11 of the unlock 
button 4 descends and the grasping arms 10 and 10 of the lock spring 3 
located at the spring holding portions 12 and 12 move along the guide 
slopes 12a and 12a so that the interval between the grasping arms 10 and 
10 is increased as shown in FIG. 8. As a result, the grasping arms 10 and 
10 are separated from the lock stage portion 6c of the electrode base 6 
and the lock between the electrode base 6 and the fitting cylinder 1 is 
released so that the electrode post connection fitting A is separated from 
the electrode post B. 
FIG. 9 is a sectional view showing an electrode post connection fitting A' 
according to a second embodiment of the present invention. In this 
embodiment, as the hollow elastic body of the electrode post connection 
fitting A', a plate-spring elastic body 15 including a plurality of plate 
springs is used in place of the foregoing coil spring 2. Other members and 
structure are the same as those of the foregoing electrode post connection 
fitting A. 
The plate-spring elastic body 15 includes an annular supporting portion 16 
and a plurality of spring portions 17 formed on the periphery of a lower 
edge 16a of the annular supporting portion 16 as shown in FIG. 10, so that 
when the plate-spring elastic body 15 is accommodated in a fitting 
cylinder 1, an upper edge 16b of the supporting portion 16 comes into 
contact with an upper inner wall 1d of the fitting cylinder 1 and free end 
portions 17a of the respective spring portions 17 come into contact with 
an electric connection conductor 13. 
When the electrode post connection fitting A' is fitted onto an electrode 
post B, the spring portions 17 are bent so as to press the connection 
conductor 13 so that the electrode post B and the connection conductor 13 
are electrically surely connected to each other as shown in FIG. 11. 
The operation for separating the electrode post connection fitting A' can 
be performed by pushing an unlock button 4 in the same manner as in the 
foregoing embodiment. 
According to the present invention, the locking and unlocking between the 
cylinder of the connection fitting and an electrode post of a battery can 
be performed by only one step of operation. Therefore, the work of 
connection and separation of the electrode post can be simplified and the 
workability in the case of connecting a large number of batteries to each 
other can be remarkably improved. Further, since the connection conductor 
is made to be in contact with the electrode post in the state where the 
former is normally urged against the latter by the device of the hollow 
elastic body such as a coil spring or the like accommodated in the 
cylinder of the connection fitting, there is such an advantage that sure 
electrical connection can be realized to obtain high reliability.