What is claimed is:
1. A lockout device for use with an energy controlling apparatus, having a rotatable shaft, such as a valve or regulator, the shaft being manually set at a desired position to control the flow of energy through said apparatus, the lockout device selectively preventing further rotation of the shaft, comprising:
a handle body and a central bore in said handle body comprising a shoulder;
a first locking means mounted in said handle body;
a second locking means comprising a lockout cap comprising:
a flat plate of generally similar configuration to the upper surface of the handle body and overlying said upper surface, said plate having an upwardly projecting cylindrical housing fixed thereto, said housing having a transversely extending opening;
a shaft also having a transverse cylindrical opening, said shaft receiving in said upwardly projecting housing and including a shaft portion projecting downwardly through said plate and to which is affixed an eccentrically mounted locking collar receivable in the central bore of the handle body;
whereby when the transversely oriented openings are aligned, the collar engages the shoulder in the central bore in the handle body so as to prevent the locking cap from removal so as to prevent access to said first locking means; and
at least one lock with a bail received in said transverse openings.
2. The lockout device of claim 1 wherein said lock with a bail comprises a padlock with a bail received in said transverse openings so as when in the locked position, to prevent rotation of said shaft relative to said upwardly projecting housing of said plate, thereby preventing disengagement of said collar from said shoulder and preventing access to said first locking means.
3. The lockout device of claim 1 wherein said lock with a bail comprises a scissors-like bail comprising a pair of pivotally connected arms each having at one end one half of a ring that is insertable in said transverse openings and at the other end an enlarged end portion with a plurality of holes which when the scissors-like bail is closed, with the ring end halves closed and engaged in said transverse openings, the holes in the enlarged end portions are aligned so that each hole may receive the bail of a separate padlock.
4. A lockout device for use with an energy controlling apparatus having a rotatable shaft, such as a valve or regulator, the shaft being manually set at a desired position to control the flow of energy through said apparatus, the lockout device selectively preventing further rotation of the shaft, comprising:
a handle body;
a central bore in said handle body comprising a shoulder;
a first locking means mounted in said handle body; and
a second locking means for receiving a plurality of personal locking devices selectively mountable on said handle body so as to prevent access to the said first locking mechanism, said second locking means comprising:
a first flat plate of generally similar configuration to the upper surface of the handle body, said plate having a arcuate section with a plurality of openings, said plate having a downwardly depending cylindrical housing for receiving a shaft;
a second flat plate of generally similar configuration to the first flat plate including the arcuate section and the plurality of openings, said second flat plate having a fixedly mounted shaft projecting through said first flat plate cylindrical housing and having a locking collar fixedly mounted to the shaft with its axis offset from the axis of said first flat plate cylindrical housing and said handle bore; and
whereby when said first and second flat plates are rotated so that said openings are in registry, said locking collar engages said shoulder in said core of said handle so as to prevent the locking cap from removal, thereby preventing access to said first locking means.
5. The lockout device of claim 4 further comprising at least one padlock with a bail received in one of said plurality of openings in said arcuate sections of said first and second plates to prevent relative rotation of said first and second plates, thereby preventing disengagement of said collar from said shoulder and preventing removal of said locking cap, thereby preventing access to said first locking means.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
That which is claimed is:
1. A glitch filter comprising:
a storage means for storing a current state, which is the output of the said filter,
the output of said storage means is connected to one input of a state comparator and the other input of the said state comparator is connected to the input signal,
a programmable clock delay means for any required duration which is independent of technology of implementation, is connected between the said state comparator and said storage means,
the arrangement being such that the input signal is stored as the new current state in the said storage means only if the input signal changes and then remains unchanged for the programmed duration.
2. A glitch filter as claimed in claim 1 wherein the said means for providing a programmable clock delay comprising:
a counter for counting clock pulses to provide a time delay, the control input of the said counter being connected to the output of the said state comparator,
the output of the said counter is connected to one input of a digital delay comparator, the other input of the said delay comparator receives a digital value corresponding to the maximum glitch width to be filtered,
the output of the said delay comparator is connected to the input of the said storage means.
3. A glitch filter as claimed in claim 2 wherein the counter is enabled only if the input to the said glitch filter is not equal to the output of said storage means and the said counter is initialized when the input of the said glitch filter is equal to the output of said storage means
4. A glitch filter as claimed in claim 1 wherein a multiplexer is provided at the output of the said storage means, which also receives the input signal at its other input and the programmable digital value for the desired maximum glitch width at its control input, the arrangement being such that when the programmed digital value is zero, the input signal is fed to the output of the multiplexer and when the value is not zero, the storage means output is fed to the output of the multiplexer.
5. A glitch filter as claimed in claim 2 wherein the number of bits used for the said counter and said digital delay comparator depends upon the desired range of programmable digital values for maximum glitch width.
6. A method for filtering glitches comprising:
storing a current state, which is the final output,
comparing the said current state with the input signal,
enabling a programmable delay whenever the input signal is different from the stored current state and initializing the programmable delay whenever the input signal is same as the stored current state,
making the stored current state equal to the input signal if the programmed delay is complete.
7. A method as claimed in claim 6 wherein programmable delay is obtained by:
counting clock pulses
comparing the counted clock pulses with a digital value corresponding to the maximum glitch width,
generating a signal indicating completion of programmed delay when the counted clock pulses become equal to the said digital value.
8. A method as claimed in claim 7 wherein the counting is enabled only if the input signal is not equal to the stored output state and counting is initialized whenever the input signal is equal to the stored output state.
9. A method as claimed in claim 6 wherein the filtering of glitches is enabled only when the digital value for desired glitch width is non-zero and is disabled when the digital value is zero.