Removable upper tie plate

Claim 2

In a nuclear power reactor fuel bundle having tie rods for securing a pair of spring-biased fuel rod mounting upper And lower tie plates in assembled position, the improvement which comprises: a. a locking means attached to the end of each of said tie rods which engages said upper tie plate and moveable relative to said tie rod and an integral seat means within an opening in the upper one of said tie plates and facing away from said fuel rods for receiving said locking means and thereby locking said tie rods into said plates against the separating force of said fuel rod springs, said locking means comprising a cylindrical member coaxially moveable relative to said tie rod and having at least one cam means projecting radially outward from the surface of said cylindrical member; b. cam operator means disposed within said opening in said upper tie plate for rotating said cylindrical member by coacting with said cam means when said tie rod is moved through said opening in the upper tie plate until said locking means is above said seat means; and c. spring means for urging said locking means into locking engagement with said integral seat means in said upper tie plate after said locking means is above said seat means and thereby securing said tie rods to said tie plate, said spring means comprising a torsion spring attached at one end to said tie rod and at its opposite end to said cylindrical member whereby said torsion spring resists rotation of said cylindrical member relative to said tie rod.

Claim 3

A nuclear power reactor fuel bundle comprising: a. upper and lower tie plates having openings therein for receiving members positioned therebetween; b. fuel rods comprising hollow tubular members having both ends inserted into said openings in said tie plates; c. spring means associated with each of said fuel rods for contacting the upper tie plate whereby said upper tie plate is urged away from the bottom tie plate by compression of said spring; d. tie rods disposed between said tie plates and secured at one end to said bottom tie plate, the other end of said tie rods having a coaxially mounted locking assembly adjustably secured at one end to said tie rod and a moveable end interconnected to said fixed end by a torsion spring and rotatable relative to said tie rod and said secured end as restrained by said torsion spring, said locking assembly having at least one cam means mounted on said rotatable end and a cam means mounted on said rotatable end and a cam operator means disposed within the opening in said upper tie plate for rotating said rotatable end relative to said secured end against the resistance of said torsion spring; e. a cam seat means disposed within said opening in the upper tie plate which receives said tie rod, said cam seat disposed on the face of said upper tie plate opposite said fuel rods and relative to said cam operator means so as to receive said cam means after rotation by said cam operator means until said cam means is positioned to enter said seat and is urged into said seat by said torsion spring and thereby to restrain said upper tie plate against the urging of said spring means.

Claim 4

A nuclear power reactor fuel bundle comprising: a. upper and lower tie plates having openings therein for receiving members positioned therebetween; b. fuel rods comprising hollow tubular members having both ends inserted into said openings in said tie plates; c. spring means associated with each of said fuel rods for contacting the upper tie plate whereby said upper tie plate is urged away from the bottom tie plate by compression of said spring; d. tie rods disposed between said tie plates and secured at one end to said bottom tie plate, the other end of said tie rods having a coaxially mounted locking assembly adjustably secured at one end to said tie rod and a moveable end interconnected to said fixed end by a torsion spring and rotatable relative to said tie rod and said secured end as restrained by said torsion spring, said locking assembly having at least one cam means mounted on said rotatable end and a cam means mounted on said rotatable end and a cam operator means disposed within the opening in said upper tie plate for rotating said rotatable end relative to said secured end against the resistance of said torsion spring; e. a cam seat means disposed within said opening in the upper tie plate which receives said tie rod, said cam seat disposed on the face of said upper tie plate opposite said fuel rods and relative to said cam operator means so as to receive said cam means after rotation by said cam operator means until said cam means is positioned to enter said seat and is urged into said seat by said torsion spring and thereby to restrain said upper tie plate against the urging of said spring means.

Claim 5

The fuel bundle of claim 2 wherein two cams are mounted on said locking assembly on opposite sides thereof.

Claim 6

The fuel bundle of claim 2 further comprising a locking projection adjacent said cam seat whereby said cam means may be prevented from reentering inclined said passageway until said tie plate is moved in a direction opposite the urging of said spring means.

Claim 7

The fuel bundle of claim 3 wherein said locking assembly comprises an anti-rotation projection disposed between said cams so as to engage a corresponding opening in said tie plate and thereby prevent said tie rod from rotating once said cams engage their respective seats.

Claim 8

The fuel bundle of claim 2 wherein said locking assembly is secured to said tie rod by a nut and a crimping sleeve.