Tamper-proof rotary plug valve

Claim 2

A tamper-proof rotary plug valve capable of being locked in a selected position by an elongated plunger-type lock member having a first enlarged head on a reduced shank and a second separate enlarged cup-shaped head arranged to receive and be locked to the shank and released from the shank by key means axially inserted into the shank, said rotary plug valve comprising a body member having a plug seat and provided with a flow passageway therethrough intercepted by the plug seat, a skirtlike extension on said body member and surrounding an open end of said plug seat, said skirtlike extension having a bore therethrough transverse to the axis of the plug seat and of a diameter to receive the heads of the plunger-type lock member, said bore in said skirtlike extension having a length at least as great as the length of the plunger-type lock member whereby the heads of said plunger-type lock member do not extend beyond the exterior of said skirtlike extension, a plug member having a flow passage therethrough, said plug member being rotatable in said plug seat between an open position in which its flow passage is in registration with the flow passageway in said body member and a closed position, said plug member having an end portion extending into the skirtlike extension and terminating no greater than flush with the outer end of said skirtlike extension, a noncircular socket in the end portion of said plug member for reception of a device to rotate said plug member, said plug member having a transverse bore in its end portion intersecting said socket and arranged to be aligned with the bore in said skirtlike extension when the plug member is in the selected position for locking, said bore in said plug member having at least a portion thereof with a diameter less than the diameter of the heads of said plunger-type lock member, but sufficient to receive the shank of the same.

Claim 3

A tamper-proof rotary plug valve as claimed in claim 1, including a handle member removably supported by said plug member, said handle member having a noncircular end portion complementary in shape to said socket in the end portion in said plug member for reception therein.

Claim 4

A tamper-proof rotary plug valve as claimed in claim 2, including means to fixedly retain said handle member against axial movement relative to said plug member.

Claim 5

A tamper-proof rotary plug valve as claimed in claim 3, in which said last mentioned means includes a set screw threadedly received in a threaded bore provided in the end portion of said plug member, said set screw engaging the noncircular end portion of said handle and said set screw being accessible through the transverse bore in said skirtlike extension.

Claim 6

A tamper-proof rotary plug valve as claimed in claim 1, in which said end portion of said plug member terminates at a predetermined distance below the end portion of said skirtlike extension and including a closure plug having an enlarged head portion and a reduced end portion of noncircular cross section complementary to the socket in said plug member, said head portion being received in said skirtlike extension and lying substantially flush with the end of the same when the end portion of said closure plug is inserted into said socket, said end portion of said closure plug having a bore therethrough arranged to be aligned with the bore in the end portion of said plug member for reception of a portion of the plunger type lock member.

Claim 7

A tamper-proof rotary plug valve as claimed in claim 1 in which said bore in the end portion of said plug member is arranged to align with said bore in said sleevelike extension when said valve is in said closed position.

Claim 8

In combination: an elongated plunger type lock member comprising a first enlarged head, a reduced shank integral with said head, and a second enlarged cup-shaped head arranged to receive and be locked to the shank and released from the shank by key means axially inserted into the shank, and a tamper-proof rotary plug valve comprising a body member having a plug seat and provided with a flow passage therethrough intersected by the seat, an annular skirtlike extension on said body member and surrounding an open end of said plug seat, said skirtlike extension having a bore therethrough transverse to the axis of the plug seat and of a diameter to receive the heads of the plunger-type lock member, said bore in said skirtlike extension having a length at least as great as the length of the plunger-type lock member whereby the heads of said plunger-type lock member do not extend beyond the exterior of the skirtlike extension, a plug member having a flow passage therethrough, said plug member being rotatable in said plug seat between an open position and a closed position for said valve, said plug member having an end portion extending into said skirtlike extension and terminating no greater than flush with the outer end of the skirtlike extension, said end portion of said plug member having a transverse bore therethrough arranged to be axially aligned with the bore through said skirtlike extension when said valve is in the closed position, said bore in said end portion of said plug member having at least a portion of its length with a diameter less than the diameter of the heads of said plunger lock, but at least as great as the diameter of the shank of the same whereby, when said valve is in said closed position, said plunger-type lock may be inserted from opposite directions into the aligned bores and locked with the heads abutting an area around the reduced portion of the bore in said end portion of said plug member to prevent axial movement of the lock member with respect to the valve plug member.

Claim 9

In combination: an elongated plunger type lock member comprising a first enlarged head, a reduced shank integral with said head, and a second enlarged cup-shaped head arranged to receive and be locked to the shank and released from the shank by key means axially inserted into the shank, and a tamper-proof rotary plug valve comprising a body member having a plug seat and provided with a flow passage therethrough intersected by the seat, an annular skirtlike extension on said body member and surrounding an open end of said plug seat, said skirtlike extension having a bore therethrough transverse to the axis of the plug seat and of a diameter to receive the heads of the plunger-type lock member, said bore in said skirtlike extension having a length at least as great as the length of the plunger-type lock member whereby the heads of said plunger-type lock member do not extend beyond the exterior of the skirtlike extension, a plug member having a flow passage therethrough, said plug member being rotatable in said plug seat between an open position and a closed position for said valve, said plug member having an end portion extending into said skirtlike extension and terminating no greater than flush with the outer end of the skirtlike extension, said end portion of said plug member having a transverse bore therethrough arranged to be axially aligned with the bore through said skirtlike extension when said valve is in the closed position, said bore in said end portion of said plug member having at least a portion of its length with a diameter less than the diameter of the heads of said plunger lock, but at least as great as the diameter of the shank of the same whereby, when said valve is in said closed position, said plunger-type lock may be inserted from opposite directions into the aligned bores and locked with the heads abutting an area around the reduced portion of the bore in said end portion of said plug member to prevent axial movement of the lock member with respect to the valve plug member.

Claim 10

The combination as claimed in claim 7, including an axially extending noncircular socket in the end portion of said plug member intersecting the bore therethrough, a closure plug having at least an end portion of noncircular cross section complementary to said socket, said end portion of said closure plug having a transverse bore therethrough arranged to be aligned with the bore in the end portion of said plug member, the bore in said closure plug having a diameter sufficient to receive at least a portion of said plunger-type lock member.

Claim 11

A combination as claimed in claim 8 in which the end portion of said plug member terminates at a predetermined distance below the end portion of said skirtlike extension and in which said closure plug includes an enlarged head on its end portion, the head being received in said skirtlike extension and lying substantially flush with the end of the same.