DK150837B - PULSE DOES - Google Patents

Description

in 150837

The invention relates to an impulse generator of the kind specified in the preamble of claim 1.

Photoelectric pulse sensors are used in many connections for the operation of binary counting devices to indicate measured quantities, such as weight and space, by means of measuring means, and to indicate the price of the measured quantity. However, the pulse sensors are mechanically coupled to the measuring devices, which switch transmits vibrations from drive means such as pumps, pistons, motors and ineffective locking means to the pulse sensor, which vibrations at e.g. interrupting the encoder causes it to pass through its connection and interrupt positions and thereby continue to emit impulses, which causes error indication on the counter.

The object of the invention is to provide an impulse generator which substantially reduces this problem.

The object according to the invention is achieved in that the impulse encoder initially stated is characterized by the characteristic part of claim 1.

The invention will now be described in more detail with reference to the drawing, in which 1 shows a hollow disc for an impulse sensor according to the invention, and FIG. 2 shows a circuit diagram of the encoder.

For the sake of simplicity, it is assumed in the following that the described embodiment is adapted for connection to a flow meter in a liquid delivery system with a pump, whereby the pulses from the impulse can be utilized to indicate the volume of the liquid delivered by the pump 150837 2. / or price.

For this purpose, the impulse sensor comprises a circular disc 1 of light-impermeable material which, with a center opening 2, must be secured to a shaft rotatable by means of the flow meter. In known manner, the disc 1 has with its center aperture a coaxial row of identical, equidistant holes 3a, which is limited by posts 3b in the disc, and is adapted to be inserted into a photoelectric sensing system, i.e. In between, a solid, light-emitting element and a fixed, light-sensitive element such that the hollow row is level with these elements. In the example, the holes 3a are square and tapering towards the center of the disc.

According to the invention, the disc 1 has a concentric second row of identical, square and equidistant holes 4a with said hole row 15, which is limited by posts 4b in the disc. In the example shown, the second row of holes is positioned within the first mentioned row of holes, and its holes 4a are substantially equal and in number equal to 20, but seen in the direction of rotation narrower than the first row of holes 3a. The axes of symmetry in the radial direction for each hole 3a and the inside hole 4a lie on one and the same radius of slices.

The second row leads in the same way as the first 25. holes for a photoelectric sensing system, i.e., it is arranged to be positioned between and level with a fixed, light-emitting element and a fixed, light-sensitive element.

In FIG. 2 shows a circuit diagram of the encoder where the holes are represented by dashed lines 3 and 4. The light emitting element of these holes, e.g. a LED, the reference numerals 5 and 6 respectively have.

The corresponding photosensitive element 7 and 8, e.g. a photodiode, transistor or resistor provides inputs to an amplifier 9 of a type known per se, e.g. SIEMENS TCA 105, which has a digital direct output 10 and a digital inverted output 11. The direct output 10, from which the pulses are passed to the volume / price indicator, is connected by means of a conductor 12 to the light emitting element 5, and the in-10 digested output 11 is connected by means of a conductor 13 to the light emitting element 6. These light emitting elements 5 and 6 are supplied from a DC source 14.

With the photosensitive element 7 of such type which is sensitive to transition from light to dark, i.e. from a hole 3a to a post 3b, and the photosensitive element 8 of such type which is sensitive to the transition from dark to light, i.e. from a post 4b to a hole 4a, the function of the impulse sensor becomes immediately clear and the following:

By switching the light from hole 3a to pole 3b, the direct output 10 goes from state 0 to 1, whereby this impulse via the conductor 12 inactivates the light-emitting element 5. The inverted output 11 thereby undergoes the state change 1 to 0 and activates, via the conductor 13 , the light-emitting element 6. The inactivated state of the element 5 and the activated state of the element 6 last until the light from the light-emitting element 6 subsequently hits - in the rotational direction of the disc 1 - hole 4a in the inner hole row, whereby the outputs 10 and 11 are subjected. the state change 1 to 0 and 0 to 1, respectively, so that the element 5 is activated and the element 6 is inactivated until the light from the light emitting element 5 associated with the outer cavity.

'4 turns over the transition from hole 3a to post 3b.

The above functional description immediately indicates that if the disc 1 after the pump is switched off, vibrations e.g. from the pump motor, so that in its plane 5 it rotates back and forth about its center axis, it can, as the light from the element 5 swings over a hole 3a to the nearest post 3b, rotate in the angular region a, i.e.. the angular region, which is limited by a pole 4b, without any impulse being obtained on the direct output 10. Similarly, when the light from the element 6 is pivoted from a pole 4b to the nearest hole 4a, the disc can rotate in the angular region β, i.e. the angular range, which is limited by the restriction sides of a hole 3a, without obtaining a signal at the direct output 10.

The pulse sensor according to the invention is in fact an effective complement to occurring sluggish return barriers, i.e. barriers which are intended to prevent disc rotation against the intended opposite direction and thereby error indication.

The invention may e.g. is modified in such a way that the wafer may consist of a light-permeable wafer with blemishes instead of posts to obtain light-impervious field. Alternatively, light-permeable and light-emitting equal fields arranged in succession 25 are often called, as in the claims, breaks.

Of course, the grids do not need to be circular or arranged on a circular disc, they may as well be band-shaped and placed on a strip which can move past the photoelectric scanning elements.

Claims (2)

Patent Claims: An impulse sensor comprising a first screen (3) for movement relative to a first light emitting means (5) and a cooperating first light-sensitive element 3 (7) which is connected in an electronic circuit (9) with a digital pulse output (10), characterized in that a second screen (4) is spaced apart from the first screen (3) for movement relative to a second light-emitting means (6) and one cooperating with said member (6) second light-sensitive means (8) and the electronic circuit (9) is designed such that passage through the second screen (4) of light from the second light-emitting means (6) to the second light-sensitive means (8) causes inactivation of the second light emitting means (6) and activating said first light emitting means (5) by impulses from said output (10), and blocking light transmittance to said first light sensitive means (7) by said first light emitting means (5) by using the first raster 20 (3) causes activation of it a the light emitting means (6) and inactivation of the first light emitting means (5) by pulses from said output (10). Pulse sensor according to claim 1, characterized in that the grids (3,4) are concentric and the first grating (3) has identical equidistant light-permeable fields (3a) and the second grating has identical identical equidistant light permeable fields (4a) of smaller width, seen in the direction of rotation, 30 than the light-permeable fields of the first frame, wherein the second-frame light-permeable fields lie amid the extensions of the first-frame light-permeable fields.