Specification
FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
AND
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2005
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION
A mechanical tripping apparatus for a circuit breaker.
APPLICANTS:
Crompton Greaves Limited, CG House, Dr Annie Besant Road, Worli, Mumbai 400 030, Maharashtra, India, an Indian Company
INVENTOR (S):
Rikame Ravindra Tukaram and Dahale Pravin Vasant, both of Crompton Greaves Ltd, A-3, MIDC, Ambad, Nasik - 422010, Maharashtra, India; both Indian Nationals.
PREAMBLE TO THE DESCRIPTION:
The following specification particularly describes the nature of this invention and the manner in which it is to be performed:
FIELD OF THE INVENTION:
This invention relates to the field of mechanical assemblies.
Particularly, this invention relates to locking mechanisms.
More particularly, this invention relates to a castle lock mechanism.
BACKGROUND OF THE INVENTION:
A lock is a mechanical device which is a security equipment for the purposes of enclosing, actuation, or the like.
Each lock has a key. In common locks, the key has a series of grooves on either side of the key (the key's blade), which limit the type of lock the key can slide into. As the key slides into the lock, the grooves on the blade of the key align with the wards in the keyway allowing or denying entry to a cylinder. Then, a series of pointed teeth and notches on the blade called bittings allow pins or wafers to move up and down until they are in line with the shear line of the inner and outer cylinder, allowing the cylinder or cam to rotate freely inside the lock and the lock to open.
Each lock has a shaft which may be operably used for a locking state or an unlocking state of the lock, depending upon the position of the shaft with respect to the lock housing. There are keys designed which are removable from the lock in both engaged and disengaged positions.
However, there are certain situations which require the use of a lock and key such that the key should be in an engaged position as long as the long is actuated or non-actuated depending upon the use. The key, should hence, remain in a locked position until the transfer of actuation state to non-actuation state, or it's vice versa, occurs.
Current equipment involves complex mechanism of machining and assembling of the same. It requires a person skilled in the art.
Hence, there is a need for an equipment which is robust and performs the intended actions in a unified uncomplicated manner.
OBJECTS OF THE INVENTION:
An object of the invention is to provide a castle lock mechanism.
Another object of the invention is to provide a lock with an actuating shaft for suitable purposes.
Yet another object of the invention is to provide a key operated lock in that the key remains engaged, in a fail-safe manner, until actuation.
Still another object of the invention is to provide a safe and robust key operated lock.
An additional object of the invention is to provide a key-engageable lock.
Yet an additional object of this invention is to provide a key operated mechanical lock and key which is easy to manufacture and assemble.
SUMMARY OF THE INVENTION:
According to this invention, there is provided a castle lock mechanism, said mechanism comprises:
a. a cam assembly which comprises an operative upper cam co-operating with
an operative lower cam, said upper cam being a slotted cylinder with a disc
base, said slot in said cylinder being adapted for allowing entry of an
external key in order to engage said cam assembly in order to actuate said
mechanism and said cam assembly being further adapted to be angularly
displaced by said external key which fits about said cam with a lever / pin in
said slot;
b. locking pin protruding from said slotted cylinder adapted to lock said
engaged key in a first operating position and further adapted to lock said
disengaged key in a second operating position;
c. at least a first pair of guided pins adapted to provide a first guided channel
for allowing movement of locking pin in an operative upward and an
operative downward direction in said first guided channel, said first pair of
guided pins located at a first position aligned with the engaged operating
position of said key;
d. at least a second pair of guided pins adapted to provide a second guided
channel for allowing movement of locking pin in an operative upward and
an operative downward direction in said second guided channel, said second pair of guided pins located at a second position aligned with the disengaged operating position of said key;
e. first screw adapted to connect said operative upper cam to said operative
lower cam at one end;
f. follower plate adapted to follow cam assembly motion, said follower plate
being inter-located between said operative upper cam and said operative
lower cam, said follower plate including a slot which receives a second
screw / projection inserted from said operative upper cam wherein, said
second screw / projection is adapted to slide from a first operative end of
said slot to a second operative end of said slot, as said operative upper cam
moves due to angular displacement of said key, thereby facilitating its
inward and outwards motion from its inter-located position between said
operative upper cam and said operative lower cam to an externally displaced
motion; and
g. shaft extending from said follower plate, said shaft adapted to follow inward
and outward movement of said follower plate, wherein said outwards
movement of said shaft is adapted to facilitate its mating external
mechanisms for purposes of locking.
Typically, said mechanism includes a pin inside said key which slides through said slot in ordered to couple the slotted cylinder of said upper cam for its engagement and further actuation.
Typically, said mechanism includes a locking plate which is located at the base of said operative upper cam and is located within a housing to receive said key.
Typically, said key is a hollow cylinder with an open base, said key being adapted to be co-axial and envelope said operative upper cam.
Typically, said mechanism includes a spring adapted to be enveloped about said operative upper cam in order to receive and absorb shock of said locking plate.
Typically, said mechanism includes an auxiliary shaft which is also actuated in an opposite direction from said shaft, in that, it extends out of said housing when said key is engaged and rotated.
Typically, said mechanism includes a spacer element in order to space said operative lower cam from the floor of said housing.
Typically, said mechanism includes spacer elements adapted to space apart upper cam from said lower cam.
Typically, said mechanism includes spacer element is placed in order to avoid the friction of the angular displacement onto the screw(s).
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
The invention will now be described in relation to the accompanying drawings, in which:
Figure 1 illustrates a front view with internal mechanisms of the castle lock mechanism;
Figure 2 illustrates a front isometric view with internal mechanisms of the castle lock mechanism;
Figure 3 illustrates a back isometric view with internal mechanisms of the castle lock mechanism;
Figure 4 illustrates an isometric view of the castle lock mechanism;
Figure 5 illustrates a front view of the castle lock mechanism;
Figure 5a illustrates a top view of the castle lock mechanism;
Figure 6 illustrates an isometric view of internal assembly of the castle lock mechanism;
Figure 7a illustrates front view of internal assembly of the castle lock mechanism;
Figure 7b illustrates side view of internal assembly of the castle lock mechanism; and
Figure 8 illustrates top view of internal assembly of the castle lock mechanism.
DETAILED DESCRIPTION OF THE ACCOMPANYING DRAWINGS:
According to this invention, there is provided a castle lock mechanism. This lock and key mechanism can be used in instances where an actuating shaft which operates between an external engaged position to an internal non-engaged position is required. Further, this lock is adapted to be used wherein the key should remain in a fail-safe engaged position, thereby disallowing its removal from the lock as long as the actuating position of the shaft is manually changed (by the key, itself). Thus, in certain instances, the same key can be operable over a plurality of lock, but can be removed from a first lock, only when its operating state is changed.
Figure 1 illustrates a front view with internal mechanisms of the castle lock mechanism.
Figure 2 illustrates a front isometric view with internal mechanisms of the castle lock mechanism.
Figure 3 illustrates a back isometric view with internal mechanisms of the castle lock mechanism.
Figure 4 illustrates an isometric view of the castle lock mechanism.
Figure 5 illustrates a front view of the castle lock mechanism.
Figure 5a illustrates a top view of the castle lock mechanism;
Figure 6 illustrates an isometric view of internal assembly of the castle lock mechanism.
Figure 7a illustrates front view of internal assembly of the castle lock mechanism.
Figure 7b illustrates side view of internal assembly of the castle lock mechanism.
Figure 8 illustrates top view of internal assembly of the castle lock mechanism.
In accordance with an embodiment of this invention, there is provided a cam assembly which comprises an operative upper cam (12) co-operating with an operative lower cam (14). The upper cam is a slotted cylinder with a disc base. The slot (18) in the cylinder is adapted to allow entry of a key (16) in the slot (18) in order to engage the cam assembly and operate the locking mechanism of the castle lock, in general. The key (16) is a hollow cylinder with a closed top and an open bottom through which it envelopes the slotted cylinder. There is a pin inside the key which slides through the slot (18) in ordered to couple the slotted cylinder of the upper cam (12) for its engagement and further actuation. This ensures that the key (16) is received over the upper cam (12) in one operative configuration only.
The portions of the cam assembly i.e. the operative upper cam (12) and the operative lower cam (14) are spaced apart by means of spacer elements (20). The cam assembly (12, 14) is adapted to be angularly displaced by the external key (16) which fits and engageably coupled about the upper cam (12) with a lever / pin in the slot. The slot, hence, facilitates the angular displacement. A screw (22) connects the operative upper cam to the operative lower cam at one end. A spacer
element is placed in order to avoid the friction of the angular displacement onto the screw(s). The slotted cylinder (16) includes an externally protruding locking pin (17) (as seen in Figures 2, 3 and 5a of the accompanying drawings).
In accordance with another embodiment of this invention, there are provided at least two pairs of guide pins (21, 23) and (25, 27). These are seen in a top view in Figure 5a of the accompanying drawings. The guide pins extend from the roof of the housing of the lock, but remain spaced apart from the operative upper cam (12). The locking pin (17) is adapted to be received in between the guide pins. Each pair of guide pins form a guide channel to allow movement of locking pin in an operative upward and an operative downward direction in the guide channels. As the key (16) slides into the slotted cylinder, and as the key presses the locking plate (32), the locking pin (17) slides downwards in a first guide channel with respect to a first pair of guide pins (21, 23). Since the guide pins only traverse a certain height from the roof of the housing, further depression of the key and the slotted cylinder of the operative upper cam render the locking pin free from the guide channel in order to be angularly displaced. While the locking pin (and hence the key) was in a first position in a first guide channel between the first pair of guiding pins, no angular displacement was possible. Further, as the key and slotted cylinder now move in an anticlockwise direction, the locking pin enters the second guide channel defined by a second pair of guide pins (25, 27) at an angularly displaced location of the slotted cylinder. The locking pin can now be raised, in the second guide channel, away from the operative upper cam in the guided channel of the second pair of guide pins. The rising of the locking pin indicates rising of the key and the key can then be removed.
In accordance with another embodiment of this invention, there is provided a follower plate (24) adapted to follow cam assembly motion. The follower plate is inter-located between the operative upper cam and the operative lower cam. The follower plate includes a slot (26) which receives a screw (28) inserted from the operative upper cam. The screw is adapted to slide from a first operative end of the slot to a second operative end of the slot, thereby facilitating its inward and outwards motion i.e. from its inter-located position between the operative upper cam and the operative lower cam to an externally displaced motion. A cam is generally adapted to convert angular motion to linear motion. Here too, the cam assembly is angularly displaced by a key, and the follower plate moves laterally (linearly).
In accordance with yet another embodiment of this invention, there is provided a shaft (30) extending from the follower plate. As the follower plate extends out, the shaft extends out. The shaft is adapted to extend out of the housing of the equipment. The emergence of the shaft mates with a lever or a female part or a plunger depending upon the use and installation of the castle lock mechanism. According to one example, it may be used in circuit breakers for manual tripping due to actuation of the shaft.
In accordance with still another embodiment of this invention, there is provided a locking plate (32) located within a housing to receive the key. The key is a hollow cylinder with an open base. This key is adapted to be co-axial and envelope the operative upper cam.
In accordance with an additional embodiment of this invention, there is provided a spring (34) adapted to be enveloped about the operative upper cam in order to receive and absorb shock of said locking plate.
During the entire operation, the key is designed to remain engaged in the slotted upper cam.
By rotating key in anticlockwise direction shaft operates outward, preferably by 15mm. The key should remain engaged. And after rotating key in clockwise direction, shaft operates inward, preferably by 15mm. Key can be removed.
As seen in Figure 4 of the accompanying drawings, another follower (36) is provided which is also actuated, in that, it extends out of said housing when the key is engaged and rotated in order to actuate some other auxiliary mechanism. It is placed upon a spacer element (38) in order to provide appropriate height to the follower.
The lower cam is also placed on a spacer element (40) in order to space the lower cam from the floor of the housing.
While this detailed description has disclosed certain specific embodiments of the present invention for illustrative purposes, various modifications will be apparent to those skilled in the art which do not constitute departures from the spirit and scope of the invention as defined in the following claims, and it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation.
We claim,
1. A castle lock mechanism, said mechanism comprising:
a. a cam assembly which comprises an operative upper cam co-operating with
an operative lower cam, said upper cam being a slotted cylinder with a disc
base, said slot in said cylinder being adapted for allowing entry of an
external key in order to engage said cam assembly in order to actuate said
mechanism and said cam assembly being further adapted to be angularly
displaced by said external key which fits about said cam with a lever / pin in
said slot;
b. locking pin protruding from said slotted cylinder adapted to lock said
engaged key in a first operating position and further adapted to lock said
disengaged key in a second operating position;
c. at least a first pair of guided pins adapted to provide a first guided channel
for allowing movement of locking pin in an operative upward and an
operative downward direction in said first guided channel, said first pair of
guided pins located at a first position aligned with the engaged operating
position of said key;
d. at least a second pair of guided pins adapted to provide a second guided
channel for allowing movement of locking pin in an operative upward and
an operative downward direction in said second guided channel, said second
pair of guided pins located at a second position aligned with the disengaged
operating position of said key;
e. first screw adapted to connect said operative upper cam to said operative
lower cam at one end;
f. follower plate adapted to follow cam assembly motion, said follower plate
being inter-located between said operative upper cam and said operative
lower cam, said follower plate including a slot which receives a second screw / projection inserted from said operative upper cam wherein, said second screw / projection is adapted to slide from a first operative end of said slot to a second operative end of said slot, as said operative upper cam moves due to angular displacement of said key, thereby facilitating its inward and outwards motion from its inter-located position between said operative upper cam and said operative lower cam to an externally displaced motion; and g. shaft extending from said follower plate, said shaft adapted to follow inward and outward movement of said follower plate, wherein said outwards movement of said shaft is adapted to facilitate its mating external mechanisms for purposes of locking.
2. A mechanism as claimed in claim 1 wherein, said mechanism includes a pin inside said key which slides through said slot in ordered to couple the slotted cylinder of said upper cam for its engagement and further actuation.
3. An mechanism as claimed in claim 1 wherein, said mechanism includes a locking plate which is located at the base of said operative upper cam and is located within a housing to receive said key.
4. An mechanism as claimed in claim 1 wherein, said key is a hollow cylinder with an open base, said key being adapted to be co-axial and envelope said operative upper cam.
5. An mechanism as claimed in claim 1 wherein, said mechanism includes a spring adapted to be enveloped about said operative upper cam in order to receive and absorb shock of said locking plate.
6. An mechanism as claimed in claim 1 wherein, said mechanism includes an auxiliary shaft which is also actuated in an opposite direction from said shaft, in that, it extends out of said housing when said key is engaged and rotated.
7. An mechanism as claimed in claim 1 wherein, said mechanism includes a spacer element in order to space said operative lower cam from the floor of said housing.
8. An mechanism as claimed in claim 1 wherein, said mechanism includes spacer elements adapted to space apart upper cam from said lower cam.
9. An mechanism as claimed m claim 1 wherein, said mechanism includes spacer element is placed in order to avoid the friction of the angular displacement onto the screw(s).
ABSTRACT
A castle lock mechanism, said mechanism comprising: a cam assembly which comprises an operative upper cam co-operating with an operative lower cam, said upper cam being a slotted cylinder with a disc base, said slot in said cylinder being adapted for allowing entry of an external key in order to engage said cam assembly in order to actuate said mechanism and said cam assembly being further adapted to be angularly displaced by said external key which fits about said cam with a lever / pin in said slot; locking pin, a first pair of guided pins, a second pair of guided pins; follower plate adapted to follow cam assembly motion, said follower plate being inter-located between said operative upper cam and said operative lower cam, said follower plate including a slot which receives a second screw / projection inserted from said operative upper cam wherein, said second screw / projection is adapted to slide from a first operative end of said slot to a second operative end of said slot, as said operative upper cam moves due to angular displacement of said key, thereby facilitating its inward and outwards motion from its inter-located position between said operative upper cam and said operative lower cam to an externally displaced motion; and shaft extending from said follower plate, said shaft adapted to follow inward and outward movement of said follower plate, wherein said outwards movement of said shaft is adapted to facilitate its mating external mechanisms for purposes of locking
