DE1814785A1 - Counting arrangement - Google Patents

Description

Counting arrangement The invention relates to an electronic counter with incremental length or angle measuring systems.

Incremental position measuring systems are known to be based on the Pulse increment method, each change in the value of the measurand in pulses counts. With incremental measuring systems there is no fixed relationship to the original starting position, so that z. B. lost the reference position in the event of a power failure goes. Another disadvantage of known incremental measuring systems is the danger the scattering of standard pulses or in the swallowing of counting pulses.

Incremental position measuring systems have also become known, where a reference pulse is used for error protection or error detection whose position in relation to the grid division of the incremental measuring system is absolutely determined is.

In these measuring systems, the electronic counter is from one Operator stopped at the reference pulse and, if necessary, from Hrnd set to the target number fixed with the reference pulse. This error checking is not only uncomfortable, but a self fraught with insecurities.

The object of the invention is to provide the Nschteile known incremental To fix measuring systems with reference pulse and by measures sm counter of the incremental Measuring system an extremely convenient, fast and reliable error check as well as such To achieve elimination of errors.

The invention is the task set in that in the counter of the Incriental measuring system scolding means are provided, each of which is one of the following Operating modes of the counter allow: 8) automatic stopping of the counter when it occurs a reference pulse used for error checking, the position of which is used to divide the Measuring system is absolutly fixed, b) automatic setting of a target number in the counter at the reference pulse and, if necessary, c) counting the incremental measuring system supplied counting pulses without taking into account those used in operating modes a) and b) Reference pulse.

An exemplary embodiment of the invention is shown schematically in the drawing shown. It shows Figure 1 is designed according to the invention incremental measuring system, FIG. 2 enlarges a marking from FIG. 1 for generating of a reference pulse, FIG. 3 shows a signal curve for FIG. 2.

Figure 1 shows a. photoelectric grating scanner for Measuring lengths. A lattice scale 10 and a lattice grating plate sliding over it 11 are illuminated by means of a lamp 12 and a condenser 15. Lenses 14 and 1, concentrate the light rays penetrating the grids 10/11 on photo elements 16 and 17. In addition to the counting track 10 '/ 1' of the grids 10/11, one from alternately Marking 18/19 provided for transparent and non-transparent fields his (Figure 2), en which a reference pulse is generated, its position in relation to the counting track 10 'of the grid 10 is absolutely fixed. A lens 20 concentrates the Marking 18/19 penetrating light beam on a downstream photo element 21. Be moving the grid 10/11 in the direction of arrow 22 is at the marker 18/19 generates a signal S (Figure 3).

The electrical signals emitted by the photo elements 16, 17 and 21 are amplified in amplifiers 23, 24 and 25 and in pulse shaping stages 26, 27 and 28 converted into square wave signals. Control the signals from photo elements 16 and 17 a direction discriminator 29, via the output 31 "forward pulses" V and via its output 30 "reverse pulses "R to an electronic Counter 32 are delivered. Those given off by the photo elements 16, 17 and 21 electrical signals are also fed to an AND gate 33. This circuit causes that the decoded reference pulse IR occurs at output 34, d. H. that the reference pulse Coincides exactly with a counting pulse in time. The reference pulse can e.g. Illumination of a lamp 35 can be perceived.

Switching means are provided in the electronic counter 32 and are shown in FIG Depending on the operating mode set, a) the counter 32 is included Occurrence of the reference pulse supplied via line 34 is stopped, so that the counter stend is held when the reference pulse is reached, b) the Counter 32 is set to the desired target number each time with the reference pulse (in Figure n connected to a u counter 32 by emitting a reference pulse electronic memory 36 in which the target number is set), c) the counter 32 the pulses generated at the counting track 10 '/ 11' of the grids 10/11 counts, and twar without Consideration of the reference pulse used in operating modes a) and b).

The respectively required operating mode a) or b) or c) of the counter 32 can be activated by operating a switch in counter 32 can be set. In the exemplary embodiment, the aforementioned operating mode is activated by actuating the switch 37 a) of the counter 32 is set, that is to say the "stop" operating mode for the reference pulse. By operating the switch 38, the operating mode b) of the counter 32 is set, this is the "setting" mode of operation for the target number for the Roferenz impulse. By pressing of the switch 39, the operating mode c) of the counter 32 is set, in which in Usually the incoming pulses without taking a reference pulse into account are counted. By operating the switch 40, the counter 32 can be switched to any Position of the object to be positioned.

The arrangement according to the invention can be used as follows: For the time being, the counter 32 is in the starting position by actuating the switch 40 of the object to be positioned is zeroed. Then by pressing the switch 37 the "stop" mode is set in the counter 32. Then the reference pulse The value stopped in the counter 32 is programmed into the memory 36. At the same time ksnn through Actuation of the switch 38 of the counter 32 to the "set" mode of operation in the memory 36 set target counter can be switched over for the reference pulse. Votes on renewed The actual number appearing in the counter 32 and the im Memory 36 set target number does not match, then each time the reference pulse the counter 32 automatically suf the f3oll-Zshl taken over from the memory 36 set, so that the reference position is restored.

This can be the right starting point, especially after a work break can be restored for further processing.

The invention is of course not only the photoelectric one shown Lattice spacing is limited, but it can also be used to generate the reference pulses magnetic, inductive, capacitive arrangements or the like.

to be used.

Several markings can be created on the measuring graduation 10 a reference pulse can be provided. In this case, the one used to control the Counter 32 or the memory 36 used marking, e.g. by means of a locking cam selected from the remaining markings.

Claims (2)

Expectations 1.) Electronic counter for incremental length or angle measuring systems, characterized in that switching means are provided in the counter (32), each allow one of the following operating modes: a) automatic stop of the counter (32) when a reference pulse used for error checking occurs, its position for the division (10 ') of the measuring system is absolutely fixed, b) automatic setting a target number in the counter (32) with the reference pulse and, if necessary, c) counting of the counting pulses supplied by the incremental measuring system (10 '/ 11') without taking into account of the reference pulse used in operating modes a) and b). 2.) Electronic counter according to claim 1, characterized by that in the counter (32) besides the usual switch (40) for zeroing the counter reading still switches (37, 38, 39) for setting the required operating mode "Stop." with reference pulse "or" Setting a target number with reference pulse "or" Counting without taking into account the reference pulse "are provided. L e r s e i t e