Connecting mechanism for pole members

A connecting mechanism for pole members to surely connect the pole members together on the common axis thereof comprises a threaded member rotatably mounted on the pole member, a tubular member mounted on the other pole member rotatably and movably in the axial direction within a predetermined range, a projection from the tubular member and openings formed with the threaded member and a spring to secure the engagement of the tubular member and the threaded member.

BACKGROUND OF THE INVENTION 
(1) Field of the Invention 
The present invention relates to a connecting mechanism for pole members, 
such as pole members used for remote control and pipes or poles for 
setting up a scaffolding for building. 
(2) Description of the Prior Art 
This invention has been made to improve a connecting mechanism for pole 
members, disclosed in my invention filed on Sept. 14, 1982 under U.S. Ser. 
No. 417,940 now U.S. Pat. No. 4,489,037 which comprises a connecting 
mechanism for pole members which remotely operate an apparatus for 
automatically adjusting a channel box fitting position relative to a 
nuclear fuel assembly. A ten meter pole is necessary to remotely carry out 
the maintenance of nuclear fuel assemblies or any other aids disposed in 
the center of a reactor vessel or a nuclear fuel pool, from a fuel 
changing machine arranged above the reactor vessel or from the sides of 
the pool. As such a pole member, a plurality of short poles are connected 
to a single pole by means of bolts in the prior art. However, any work or 
operations in a nuclear reactor or power plant should be strictly carried 
out in view of safety. If the used parts are falling into the center of 
the nuclear vessel or the fuel pool while changing them to the 
corresponding new parts, the parts fallen onto the bottom of the reactor 
vessel or the fuel pool must be collected certainly even if the parts is 
only a small bolt or nut, otherwise the nuclear reactor cannot be 
operated. 
Accordingly, the connecting mechanism for the remote control pole member 
should be precisely and surely constructed even if it becomes somewhat 
expensive. Further, it is required to easily carry out a connecting 
operation of the pole members, otherwise the efficiency of parts changing 
work will be lowered. Therefore, such a connecting mechanism which surely 
connects pole members one another with a simple connecting action, was 
required. Then, I proposed to provide a threaded member with a pole member 
and to engage same with a male thread formed with another pole in the 
state that each of the ends of the pole members is contacted and fixedly 
connected each other in the direction of the common axis thereof, and to 
provide with each of the ends of the pole members a fittingly engaging 
portion which connects both the pole members to be integrally rotatable. 
This connecting mechanism is constructed to prevent the threaded member 
from releasing due to relative rotation of the pole members for operation 
by using a fitting engagement of the fittingly engaging portion formed 
with the ends of the pole members. However, there is provided a clearance 
for play between the fittingly engaging portions in order to easily make a 
fitting engagement in the direction of the common axis of the pole 
members. Therefore, when the pole members receive an external force due to 
vibration or hand operation, they are easily rotatable within the range of 
the clearance and thereby the threaded member of the pole member is 
rotated slightly relative to the other pole member. Accordingly, once the 
threaded member rotates slightly in the direction of release, the 
tightening force by the threaded member is remarkably reduced, and as, 
result the threaded the member is further easily totatable in the 
direction of release and if the pole members are used continuously, the 
connecting mechanism between the pole members becomes cranky and gets out 
of joint. 
SUMMARY OF THE INVENTION 
In view of the above mentioned circumstances, an object of the present 
invention is to easily carry out a fitting engagement between the pole 
members in the direction of the common axis thereof and to surely and 
fixedly connect the pole members without release and further to easily 
make a connecting operation. 
To achieve the above object, a connecting mechanism for pole members 
according to the present invention comprises a pole member having a male 
screw on the periphery of an end thereof and a fittingly engaging portion 
at the end face thereof, another pole member having a fittingly engaging 
portion at an end face thereof to engage with the fittingly engaging 
portion of the said pole member in the rotation axis thereof, a threaded 
member of tubular shape mounted on the said another pole member to be 
rotatable and within a predetermined range movable in the axial direction 
thereof, the threaded member being provided with, on the inner wall 
thereof, a screw engagable with the said male screw of the said pole 
member and a plurality of openings at an end face thereof, a tubular 
member mounted on the end of the said pole member to be rotatable and 
movable in the axial direction thereof within a predetermined range, the 
tubular member being provided with at least a pin engagable with the said 
openings, and a spring urging the said tubular member in the direction of 
engagement of the pin and in the direction of tightenning of the threaded 
member, whereby the said pole member and the another pole member are 
fixedly connected by selectively engaging the pin with one of the openings 
in the state that the tubular member is rotated against the urging force 
of the spring. 
Namely, leaving an advantage of easily engaging the pole members together 
in the axial direction by providing a clearance of play between each of 
the fittingly engaging portions formed respectively on the end faces of 
the pole members, the present invention enables to give the threaded 
memebr an urging force in the direction of tightenning, by utilizing a 
return force of the spring, by selectively engaging the pin with the 
opening in the state that the tubular member is rotated against the urging 
force of the spring after tightenning of the threaded memeber. Therefore, 
even if vibration or operating force by hand acts on the pole members, the 
threaded member may not be rotated unexpectedly in the direction of 
release and the pole members are fixedly and surely connected each other. 
Further, by utilizing the operation of rotating and moving the tubular 
member in the axial direction, the pin is engaged or disengaged with the 
opening. Therefore, while obtaining the above mentioned advantages, the 
present invention simplifies the connecting operation of the pole members 
in comparison with the case of using a particular pin which prevent the 
engagement of the pole members from releasing. 
It will be understood in view of the above mentioned advantages of the 
present invention that the connecting mechanism of the present invention 
is preferable to the pole members which requireds reliability in operation 
or applicable to the pipes for setting up a scaffolding for building.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 shows an example of a hand operation pole having a mirror used in a 
water for detection. This pole is used to remotely carry out the 
maintenace of nuclear fuel assemblies or any other aids disposed in the 
center of a reactor vessel or a nuclear fuel pool, from a fuel changing 
machine arranged above the reactor vessel or the sides of the fuel pool. 
This pole comprises two pole members (A), (B) which may be fixedly 
connected and disconnected on the same axis. A gear box (D), to which a 
mirror (C) is pivoted, is detachably connected to an end of one of the 
pole members (A). Detachably connected to an end of the other pole member 
(B) is a handle (E) which operates the mirror (C) in a desired direction 
through remote control shafts (1), (2), described hereinafter, which are 
installed within the pole members (A), (B) and via a worm gear (not 
illustrated) arranged in the gear box (D). There are slight differences in 
the detailed construction of the connecting mechanism between the pole 
members (A), (B) or one of the pole member (A) and the gear box (D) or the 
other pole member (B) and the handle (E) since the objects to be connected 
are different. However, the essential construction of these connecting 
mechanisms are basically the same. Therefore, this embodiment only refers 
to the connecting mechanism between the pole members (A), (B). 
As shown in FIG. 2 through FIG. 9, the pole member (A) comprises a pole 
body (3) at an end of which a male screw member (5) is fixed and the other 
pole member (B) comprises a pole body (4) at an end of which a female 
screw member (6) is fixed. Connecting members (7), (8) of tubular shape 
which are attachable in the axial direction thereof, are screwedly 
connected to the male and female screw members (5), (6) respectively. The 
male screw member (5) is fixed to the connecting member (7) and the female 
screw member (6) to the other connecting member (8) by means of bolts (9) 
respectively. A threaded member (10) of tubular shape is mounted on the 
connecting member (8). The threaded member (10) has a ringlike projection 
(10a) which is contactable with a flange (8a) of the connecting member 
(8), and may be screwedly engaged with the male screw member (7a) of the 
other connecting member (7) so that the connecting members (7), (8) are 
fixedly connected each other on the same axis. Fittingly engaging portions 
(11), (12) in a trapezoid shape are respectively formed with the end of 
the connecting member (7) and the end of the other connecting member (8) 
facing the end of the said connecting member (7) so as to connect the 
connecting members (7), (8) to be integrally rotatable by making a fitting 
engagement in the axial direction. 
On the other connecting memebr (7) there is mounted a tubular member (15) 
to be slidable in the axial direction thereof and rotatable around the 
axis thereof. The tubular member (15) has at least a pin (14) which 
selectively fits into a plurality of openings (13) which are 
circumferentially bored on the end face of the threaded member (10). This 
tubular member (15) is separable into tubular members (15A), (15B) of gate 
form in section which are facingly opened to each other. These separate 
tubular members (15A), (15B) are screwed together and fixedly connected by 
means of screw means. 
The separate tubular member (15A) located on the side of the threaded 
member (10) is formed with a guide groove (17) which controls rotation and 
movement in the axial direction of the tubular member (15) by engaging 
with a projection fixedly screwed to the other connecting member (7). 
Between the separate tubular member (15A) and the other connecting member 
(7) there is disposed a compressed and slightly tapered spring (18) which 
urges the tubular member (15) in the direction of engagement of the pin 
(14) and in the direction of tightenning of the threaded member (10). 
The guide groove (17) comprises a cam face (17a) and a slanted cam face 
(17b). The cam face (17a) is formed to be capable of keeping the pin (14), 
by contacting the projection (16), in the disengaging position in which 
the pin is released from the opening (13) against the urging force of the 
spring (18) in the direction of engagement of the pin when the tubular 
member (15) is rotated maximally toward the returning direction of the 
spring (18), as shown in FIG. 7. The slanted cam face (17b) is formed to 
be capable of producing, by contacting the projection (16), a component 
force (F'2) in the direction of tightenning of the threaded member (10) by 
the urging force (F2) of the tubular member (15) in the direction of 
engagement of the pin (14) when the pin (14) is selectively fittingly 
engaged with the opening (13) in the state that the tubular member (15) is 
rotated against the urging force of the spring (18), as shown in FIG. 8 
through FIG. 10. 
Accordingly, when the pin (14) is selectively engaged with the opening 
(13), as shown in FIGS. 9 and 10, it is possible to surely and powerfully 
stop the rotation of the threaded member (10) in the direction of 
releasing by utilizing a resultant force (F3) totally the urging force 
(F1) of the spring (18) in the direction of tightenning of the threaded 
member (10) and the component force (F'2). 
When the pin (14) does not fit into the opening (13) in the state that the 
tubular member (15) is rotated maximally against the urging force of the 
spring (18), it is necessary to fit the pin (14) into the opening (13) by 
slightly rotating the tubular member (15) in the direction of releasing. 
However, the slanted cam face (17b) is formed to cover a range 
corresponding to a pitch of the openings (13) so as to produce the 
component force (F'2) in the said situation. 
The pin (14) is constructed by utilizing an end of the spring (18). 
Supposed that the projection (16) is located in a position indicated with a 
phantom line as shown in FIG. 10, the spring (18) may be designed to have 
no urging force in the direction of tightenning of the threaded member 
(10) and in the direction of engagement of the pin (14), or may be 
designed to have beforehand a suitable urging force in both the directions 
of engagement of the pin and tightenning of the threaded member. 
Next, it is described about the remote control shafts (1), (2) installed in 
the pole members (A), (B) respectively. Screwedly fixed to, via a spring 
pin, a female screw member (19) provided with an end of the remote control 
shaft (2), is a hollow female joint (20) which is contactable with the 
inside walls of the connecting members (7), (8) so as to accord an axis of 
the connecting member (7) with an axis of the other connecting member (8). 
Screwedly fixed to, via a spring pin, a female screw member (21) provided 
with an end of the other remote control shaft (1), is a male joint (22) 
which is inserted into a cornered bore (20a) of the female joint (20) in 
the axial direction and engaged therewith in the state of integrally 
rotating. 
Further, on the peripheries of the joints (20), (22) there are formed 
circumferential grooves (23), (23) which stop the joints from moving in 
the axial direction thereof, but allows same to be rotated by fittingly 
engaging the tip ends of the screws (9). 
There is disposed respectively a seal member (24) such as a O-ring between 
the female joint (20) and the inner wall of the connecting member (8) 
facing the said peripheral face or the peripheral face of the connecting 
member (8) and the inner wall of the female screw member (6) facing the 
said peripheral face, or the peripheral face of the male joint (22) and 
the inner wall of the male screw member (5) facing the said peripheral 
face. 
Both the remote control shafts (1), (2) are the same in construction. Each 
of the ends of the shafts (1), (2) near the female joint (20) has an 
opening (25) respectively which checks a sealing effect of the seal member 
(24) by flowing an air from the cornered bore (20a) of the female joint 
(20) into a ringlike space between the pole bodies (3), (4) and the remote 
control shafts (1) (2). 
After checking of the sealing effect, a plug is screwed to a 
tapered-connecting screw member (20b) for a blowing tube (not illustrated) 
formed inside the female joint (20) to close the tube. 
The pole bodies (3), (4) and the remote control shafts (1), (2) are made of 
aluminium pipes and the connecting portions thereof are made of stainless 
steel. Further, sealing of the above construction gives a great buoyancy 
to the pole members (A), (B) when the mirror is used in a water so that 
the mirror may be easily operated in a water. As shown in FIG. 7 through 
FIG. 10, in the case that the guide groove (17) comprises a cam face (17a) 
formed to be capable of keeping the pin (14) in the disengaging position 
in which the pin (14) is released from the opening (13) against the urging 
force of the spring (18) in the direction of engagement of the pin when 
the tubular member (15) is rotated maximally toward the returning 
direction of the spring (18), and a slanted cam face (17b) formed to be 
capable of producing, by contacting the projection (16), the component 
force (F'2) in the direction of tightenning of the threaded member (10) by 
the urging force (F2) of the tubular member (15) in the direction of 
engagement of the pin (14) when the pin (14) is selectively fittingly 
engaged with the opening (13) in the state that the tubular member (15) is 
rotated against the urging force of the spring (18), it is not necessary 
to keep the tubular member (15) in a disengaging position against the 
urging force of the spring (18) whenever the pole members (A), (B) are 
connected fixedly and as the result a connecting operation is further 
simplified and quickened. 
Further, a part of the urging force of the spring (18) in the direction of 
engagement of the pin, is utilized as the urging force for tightenning the 
threaded member (10), so that the pole members (A), (B) are powerfully 
fixed though the spring (18) is small one. 
FIG. 11 shows another embodiment which installs in the pole members (A), 
(B) pipes (1'), (2'), for fluid for operating actuators such as air 
cylinders instead of the remote control shafts (1), (2). In this 
embodiment, the above mentioned first embodiment is partly modified as 
follows: 
(A) The male joint (22) is formed hollowly. 
(B) The opening (25), the plug and the spring pin are omitted and liquid 
for preventing the threaded member from releasing is coated therewith. 
(C) A seal member (24) such as a O-ring is disposed respectively between 
the engaging faces of the joints (20), (22) or between the engaging faces 
of the female joints (20) and the female screw member (19) of a pipe (2') 
for fluid or between the engaging faces of the male joint (22) and the 
male screw member (21) of the other pipe (1') for fluid. 
(D) In the joints (20), (22) tapered screw member (20b), (22b) are formed 
for an air blowing tibe (not illustrated) for sealing check. 
FIG. 12 shows another embodiment utilizing the pole members (A), (B) as 
operating shafts. In this embodiment, the essential construction is the 
same as those of the above first and second embodiments. Since there is 
disposed no remote control shaft (1), (2) or pipes (1'), (2') for fluid, 
the connecting members (7), (8) are fixed, via spring pins (26), to the 
tubular members (29), (30) fixed to the pole bodies (3), (4). Further, the 
guide pin (27) for centering an axis disposed in the connecting member 
(8), is fixedly connected to the other connecting member (7) via the 
spring pin (28). 
The guide groove (17) may be formed in the shapes as shown in FIG. 13a 
through FIG. 13d. 
In the embodiment of FIG. 13a, the tubular member (15) cannot be kept in a 
disengaged position against the urging force of the spring (18) in the 
axial direction thereof. 
In the embodiment of FIG. 13b, when the tubular member (15) is rotated 
maximally against the urging force of the spring (18) and where the pin 
(14) does not fit the opening (13), it is necessary to operate the 
threaded member (10) in the direction of releasing within a pitch of the 
opening (13). 
In the embodiment of FIG. 13c, as is the same case of each of the 
embodiments of FIGS. 13a and 13b, the above mentioned component force 
(F'2) is not produced and release of the threaded member (10) is stopped 
only by the urging force (F1) of the spring (18) in the direction of 
tightenning of the threaded member. 
In the embodiment of FIG. 13d, the cam face (17a) extends towards the 
terminal portion of the slanted cam face (17b). 
Further, the above constructions may be partly modified as follows: 
(a) A plurality of openings (13) may be formed with the tubular member (15) 
and a pin (14) is provided with the threaded member (10). 
(b) The guide groove (17) may be concaved within the thickness of the 
tubular member (15). 
(c) The guide groove (17) may be formed with a third member such as a 
projection connection to the tubular member (15). 
(d) The guide groove (17) may be formed with the other connecting member 
(7) and the projection (16) may be provided with the tubular member (15). 
Although the above embodiments refer to the connecting mechanism for the 
remote control members in relation to the nuclear fields, the present 
invention of course applies to any kinds of pipes such as those used for 
setting up a scaffolding for building.