Tamper proof lock
First Claim
1. In a fire hydrant including a bonnet having an aperture, a housing having an internal chamber, a threaded operating rod extending within the housing chamber coupled to a yoke, and a plunger coupled to the yoke for opening and closing a valve, a tamperproof lock comprising:
- a spring mounted at one end on a housing;
power transmitting means threadedly mounted on a threaded operating rod extending within a housing chamber for transmitting power to said threaded rod againt said spring; and
a swivel plate freely mounted on said power transmitting means for rotational movement thereon, said swivel plate having a contoured hub portion adapted to fit within a bonnet aperture, said hub portion being exposed to the exterior of the bonnet.
0 Assignments
0 Petitions
Accused Products
Abstract
A tamperproof lock for a fire hydrant. A spring is mounted at one end on the fire hydrant housing. Power transmitting means are mounted on a threaded operating rod extending within the housing chamber. The power transmitting means transmit power to the threaded rod against the spring. A swivel plate is freely mounted on the power transmitting means for rotational movement thereon. The swivel plate has a contoured hub portion adapted to fit within an aperture within the fire hydrant bonnet. The hub portion is exposed to the exterior of the bonnet. Power means for applying power substantially along the axis of the threaded rod to move the rod against the spring are removably mounted on the bonnet. Means for preventing axial and rotational movement of the power means is pivotably connected thereto by means of a double pivot joint.
18 Citations
11 Claims
-
1. In a fire hydrant including a bonnet having an aperture, a housing having an internal chamber, a threaded operating rod extending within the housing chamber coupled to a yoke, and a plunger coupled to the yoke for opening and closing a valve, a tamperproof lock comprising:
-
a spring mounted at one end on a housing; power transmitting means threadedly mounted on a threaded operating rod extending within a housing chamber for transmitting power to said threaded rod againt said spring; and a swivel plate freely mounted on said power transmitting means for rotational movement thereon, said swivel plate having a contoured hub portion adapted to fit within a bonnet aperture, said hub portion being exposed to the exterior of the bonnet. - View Dependent Claims (2, 3, 4)
-
-
5. In a fire hydrant including a housing having an internal chamber and an internally threaded portion, a threaded operating rod extending within the housing chamber coupled to a yoke, and a plunger coupled to the yoke for opening and closing a valve, the combination comprising:
-
a modified retaining ring threadedly mounted on an internally threaded portion of a housing; an operating nut converter threadedly mounted on a threaded operating rod extending within a housing chamber; a pressure plate threadedly mounted on said operating nut converter, said pressure plate having an annular recess formed in its underside and a circular recess formed in its topside; a swivel plate freely mounted in said pressure plate circular recess for rotational movement therein, said swivel plate having a conically shaped central hub portion; and a spring mounted at one end on the housing and adapted to fit at the other end within said pressure plate annular recess whereby said spring exerts an upward force against the underside of said pressure plate. - View Dependent Claims (6, 7)
-
-
8. In a fire hydrant including a bonnet having an aperture, a housing having an internal chamber, a threaded operating rod extending within the housing chamber coupled to a yoke, and a plunger coupled to the yoke for opening and closing a valve, a tamperproof lock comprising:
-
a spring mounted at one end on a housing; power transmitting means threadedly mounted on a threaded operating rod extending within a housing chamber for transmitting power to said threaded rod against said spring; a swivel plate freely mounted on said power transmitting means for rotational movement thereon, said swivel plate having a contoured hub portion adapted to fit within a bonnet aperture, said hub portion being exposed to the exterior of the bonnet; and power applying means removably mounted on the bonnet for applying power substantially along the axis of the operating rod to move the rod against said spring by contacting the contoured hub portion of said swivel plate.
-
-
9. In a fire hydrant including a housing having an internal chamber and an internally threaded portion, a threaded operating rod extending within the housing chamber coupled to a yoke, and a plunger coupled to the yoke for opening and closing a valve, the combination comprising:
-
a modified retaining ring threadedly mounted on an internally threaded portion of a housing; an operating nut converter threadedly mounted on a threaded operating rod extending within a housing chamber; a pressure plate threadedly mounted on said operating nut converter, said pressure plate having an annular recess formed in its underside and a circular recess formed in its topside; a swivel plate freely mounted in said pressure plate circular recess for rotational movement therein, said swivel plate having a conically shaped central hub portion; a spring mounted at one end on the housing and adapted to fit at the other end within said pressure plate annular recess; a bonnet coupled to the housing, said bonnet having an aperture for receiving said conically shaped central hub portion of said swivel plate and a wall provided with a pair of holes in the exterior thereof; and means removably mounted on said bonnet for exerting a force substantially along the axis of the operating rod to move the rod against said spring by contacting the central hub portion of said swivel plate.
-
-
10. Apparatus, comprising:
-
a bonnet; a housing coupled to said bonnet having an internal chamber; a threaded operating rod extending within said housing chamber; a spring mounted at one end on said housing; power transmitting means threadedly mounted on said operating rod for transmitting power to said rod against said spring; and swivel means rotatably mounted on said power transmitting means, said swivel means having a contoured portion exposed to the exterior of said bonnet. - View Dependent Claims (11)
-
Specification