Measuring and testing – Instrument proving or calibrating – Volume of flow – speed of flow – volume rate of flow – or mass...
Patent
1991-01-03
1993-03-30
Raevis, Robert
Measuring and testing
Instrument proving or calibrating
Volume of flow, speed of flow, volume rate of flow, or mass...
G01P 2100
Patent
active
051973219
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a control device having a movable operating element for introducing and forwarding an input command to control systems, particularly of machines, plant or the like
Most of the control devices which can be found on the market convert the input commands introduced into their operating element, for example push buttons, switching bar, switching plate and so forth into other physical quantities such as electrical signals, pressures, flows and the like which are then forwarded in this form to control systems, particularly of machines or plant.
If the mechanically movable operating element or if movable parts forming a functional unit with the latter (which are also designated as operating element in the text which follows), such as internal plungers, levers and so forth of such control devices are blocked without being noticed or if they lose adequate mobility as result of jamming, corrosion in the bearings, wedging or other influences, an input command introduced will not be accepted and, in consequence, also not be forwarded and processed. This is particularly hazardous if these are commands for stopping or for preventing the starting of machines and plant.
It is the object of the invention to design a control device with operating element in which the mobility of the mechanically movable operating element is continuously automatically monitored and when adequate mobility is lost, the same output signal is generated which would also be generated by the introduction of an input command in undisturbed operation.
The object is achieved by the fact that an oscillating movement is imparted to the operating element by a drive, this movement is forwarded by the operating element to a sensor and is detected by the latter, in which arrangement the introduction of an input command damps the oscillating movement According to the invention, a continuous oscillating movement of a particular amplitude is imparted by a suitable drive to the operating element to be mechanically moved by the input command for as long as no input command is introduced and adequate mobility exists. In this arrangement, for example, a magnetic system can be used as a drive which consists, in particular, of an electromagnet and an armature connected to the movable operating element. Similarly, pneumatic, hydraulic, capacitive or piezoelectric forms of drive are conceivable In this arrangement, the direction of the movement, which is dependent on the input command relative to the oscillating movement, can be arbitrary.
The oscillating movement of the mechanically movable operating element is appropriately detected by a suitable sensor, for example an electromechanically, pneumatically, hydraulically, capacitively, piezoelectrically or otherwise acting system and emitted as sensor signal which, for example after discrimination in an amplitude discriminator, can be emitted as binary output signal to the subsequent control system of the machine or plant.
The drive can be fed with external excitation by its own oscillator or with self-excitation by feeding back the sensor signal into the drive.
If an input command is introduced into the operating element, it is subjected itself (and all oscillating components of it), for example by coming to rest against a friction surface or a fixed stop, to a restriction of mobility, so that no signal or only a small signal is introduced into the sensor. This damping can also be effected additionally or only by emitting vibration energy into the medium introducing the input command, for example, the hand of a person or the rising of a fluid, whereby the medium surrounding the operating element changes from gaseous to liquid; the same effect occurs if the mobility is reduced unintentionally by internal or external influences such as corrosion in the bearing points, fracture of the parts carrying the mechanically movable operating element, such as springs and so forth.
The reduction in the amplitude of the sensor signal thus caused indicates that the operating element has been loaded by an int
REFERENCES:
patent: 3045476 (1962-07-01), Bell
patent: 3100292 (1963-08-01), Warner, Jr. et al.
patent: 3100393 (1963-08-01), Bell
patent: 3224245 (1965-12-01), Alibrandi et al.
patent: 3768832 (1973-10-01), Schmidt
patent: 3830091 (1974-08-01), Sinsky
patent: 3937913 (1976-02-01), Soulas et al.
patent: 4644315 (1987-02-01), Hodges
patent: 4754644 (1988-07-01), Valentini
Dunn Michael L.
Raevis Robert
Simpson Robert P.
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