Home

Primary Examiner: Shaw, Gareth D.
Assistant Examiner: Rhoads, Jan E.
Attorney: Lorin; C. M.

Next ten patents ordered by date:

Byte-by-byte type processor circuit
Microcomputerized electronic postage meter system
Selectively erasable optical memory system utilizing a photo excitable ferroelectric storage plate
High density MOS memory array
Temperature indicating device for fluids
Three wire detection circuit
Oscillator energized liquid level indicator
Means for sensing change in the amount of fluent material in a reservoir
Line isolation monitor
Alarm system including remote signalling means

Translate:
En
De
Es
Fr
It
Pt
Ja
Ko
Zh

Title: System and method for programmable sequence control

Abstract: A programmable sequence controller for controlling a machine or process operation including a main low-security programmed sequencer and a high-security programmed sequencer through which selected outputs from the main sequencer must pass before being allowed to control the machine or process operation. This high-security sequencer generates a sequence of steps which relate to machine or process commands under conditions critical to the operation of the machine or process and is controlled in a predetermined order. Any critical output requested by the main sequencer is caused to initiate sequencing by the high-security sequencer and is tested by the high-security sequencer as to the propriety of the generation of a permitted output to the machine or process. The high-security sequencer in this manner effects an improved interlocking between the various critical output commands and actual operative conditions.

Do you think this is a good invention? Vote now:

Votes so far: For:(0) Against:(0)
Other info:

Inventors: Willard, Frank G. (Monroeville, PA, US)

Application Number: 481267
Filing Date: 1974-06-20
Publication_date: 1976-08-31
Assignee: Westinghouse Electric Corporation (Pittsburgh, PA)
Primary Class(es): 700/1
Other Classes:
US Patent Ref:

3514758	May, 1970	Bennett	340/172.
3585603	Jun, 1971	Ross et al.	340/172.
3651482	Mar, 1972	Benson	340/172.
3701113	Oct, 1972	Chace et al.	340/172.
3707703	Dec, 1972	Sakai	340/172.
3719931	Mar, 1973	Schroeder	340/172.
3741246	Jun, 1973	Brantenbah	340/172.
3753243	Aug, 1973	Ricketts et al.	340/172.
3763474	Oct, 1973	Freeman et al.	340/172.
3764995	Oct, 1973	Helf et al.	340/172.
3783251	Jan, 1974	Pavkovich	340/172.
3825901	Jul, 1974	Golnek et al.	340/172.
3875391	Apr, 1975	Shapiro et al.	340/172.

Other Refs: Other References: "Programmable Logic Controllers--An Update", N. Andreiev Control Engineering, Sept. 1972, pp. 45-47.
"Programmable Logic Controllers--Painless Programming to Replace the Relay Bank", G. Lapidus, Control Engineering, Apr. 1971, pp. 49-60.