HU216518B - Device for operating exhaust air equipment - Google Patents

Abstract

The present invention relates to a device for operating a ventilating device, which can be controlled or controlled by means of operating means, by means of which the flow rate of the flow of exhaust air can be inflated. The device according to the invention comprises: a) a one-speed operation, the flow velocity (V) of the outgoing air stream (LS) decreasing below a pre-lowered threshold value (Vmin) in the ventilation device (AA), or a binary flow sensor (SE) providing a binary signal thereof, b) a binary flow detector (SE) -based computer (SPS) computer, a first-aid control operated by a preprogrammed bayonet, guided by at least a binary sensor signal (BS) for binary flow sensing (SE), and having a flow of air flow control and / or air flow (LS) the reduction of the flow rate below the predetermined lower limit value (Vmin) is directed to the operating means of the venting device (AA) of the megacontroller outputs. ŕ

Description

The invention relates to a device for operating a ventilation device. Ventilators for the ventilation of small-scale workshops or industrial production equipment often need to remove heavily contaminated air with solid particles. For example, pottery, woodworking and processing workshops are exposed to heavy dust and wood chips emissions. Such clouds of particulate matter should be sucked off as directly as possible at the place of origin, primarily for occupational safety reasons (eg "Technische Regein für Gefahrenstoffe", Technical Regulations for Hazardous Substances).

GB 2 136560 A discloses a ventilation device for enclosed spaces or chambers, in particular for several draft cabinets. Here, closing of many draft cabinets may cause the pressure in the exhaust air manifold to drop too much. This condition is detected by a pressure sensor. As a result, the ventilation unit rotation speed is reduced to avoid, on the one hand, excessive power consumption of the ventilation unit and, on the other hand, excess cooling in the draft cabinets.

Finally, a control device for a ventilation device is known from CA 1 273 524. This known control device has a safety switch for evaluating the exhaust air flow, which switches off the ventilation unit in the event of an insufficient supply of exhaust air.

The exhaust air flow rate inside the unit should not be less than a minimum value to maintain the ventilation unit's functionality. Otherwise, there is a risk that impurities can accumulate inside the unit. As a result, conveyance performance may be adversely affected by cross-sectional congestion and, in the worst case, by congestion, so that the required extraction of contaminated air from the machinery is no longer ensured. For example, ventilation systems for the removal of wood and wood shavings require a minimum air velocity of more than 20 m / s in the case of dry shavings and 30 m / s in the case of wet shavings, according to the Technische Regein für Gefahrenstoffe (TRGS 553).

It is a problem that measurement of the actual value of the exhaust air flow rate in the exhaust air manifold or other suitable location in the duct system of the ventilation device is generally not possible for various reasons. A sensor built into the pipeline system would become unusable even after a short operating time without special, costly preventive measures due to contamination or mechanical damage. In addition, both the investment and the maintenance costs of a ventilating device with a reliable measuring device for measuring the velocity of the exhaust air flow would be high, so that the construction and operation of such a device would be a significant burden especially for small and medium-sized industrial and industrial plants.

The object of the present invention, on the other hand, is to provide a simple and robust device, which can be retrofitted, if necessary without much expense, to operate a ventilation device which maintains a predetermined minimum outflow velocity without directly observing the actual analogue current flow rate. .

According to the invention, this object is solved by providing a device for operating the ventilation device, which comprises controllable or controllable operating means for controlling the flow rate of the outgoing air stream.

(a) an electrically operated binary flow sensor which outputs a binary signal when the outgoing air flow rate through the ventilation system drops below or exceeds a predetermined lower limit; and

(b) a program-controlled computer, in particular a controller with programmable storage, having at least a binary sensor signal of the binary flow sensor and controlling the means for operating the ventilation device so that the outgoing air flow rate does not fall below a predetermined lower limit.

Preferably, the venting apparatus comprises a venting apparatus for generating an outgoing air stream as a controllable or controllable operating means, to which are programmed computer signals, in particular on and off signals and / or speed control signals.

The venting device includes, as a controllable or controllable operating means, electrically operated shut-off valves for the suction manifolds, preferably located at their suction-side ends and receiving signals from a program-controlled computer, in particular for opening or closing.

Includes a binary flow sensor

a) a swing damper, preferably located in the central exhaust air manifold of the ventilation device so that when there is no outgoing air flow, the outgoing air manifold is closed and automatically closed by an outgoing air stream,

(b) a binary sensing element, in particular a photocell or an inductive proximity switch, which, when the flap is open, transmits a binary sensing signal when it enters or exits the detection area of the sensor; and

(c) means for adjusting the binary sensor element to adjust the entry or exit of the swing damper into the detection area of the sensor to a predetermined lower limit of the exhaust air flow rate.

HU 216 518 Β

The invention will now be described in more detail with reference to the accompanying drawings, in which:

Figure 1 is a block diagram of an exemplary industrial production unit with ventilation equipment,

Figure 2 is a sectional view of a first preferred embodiment of a binary flow sensor in an operating device according to the invention,

Figure 3 is a sectional view of a second preferred embodiment of a binary flow sensor in an operating device according to the invention,

Figure 4 is a view of the second embodiment of the flow sensor of Figure 3, a

Figure 5 is a possible measurement sequence at the output of the flow sensor of the operating device according to the invention, a

Fig. 6 is a measurement sequence of Fig. 5 with additional signal filtering.

In the block diagram of Figure 1, there are, for example, three machines BM1, BM2 and BM3 in the industrial production unit. These can be planers, saws or grinders in a woodworking workshop. Under certain circumstances, these machines emit strong clouds of particulate matter, which, for safety reasons in particular, should be sucked in as directly as possible at source.

For this purpose the AA ventilation unit is used. According to the block diagram of Fig. 1, the ventilation device comprises, by way of example, the suction nozzles AB1, AB2 and AB3, which are directly assigned to the respective implement BM1, BM2 and BM3. The intake manifolds flow into the AR exhaust air manifold, in which, under certain conditions, an AG ventilation unit generates an outflow air stream of LS loaded with solids. The exhaust air flow LS has a flow velocity V and, for example, is discharged into the environment through the outlet nozzle AS, which serves as an air outlet LE, at the end of the exhaust air manifold AR. The venting device includes, finally, controllable or controllable operating means for controlling the value of the flow velocity V of the outgoing air flow LS.

In the example shown in the block diagram of Fig. 1, such controllable or adjustable actuating means in the ventilation unit AA are provided by the shut-off valves VS1, VS2 and VS3 belonging to the suction ports AB1, AB2 and AB3. These are preferably located at the suction end of the suction nozzles and can be locked, for example, when the appropriate implement is switched off. By closing and opening each of the shut-off valves at the end of the suction nozzles, the suction power of the ventilation device at the adjacent suction nozzles and the flow velocity V of the exhaust air flow LS as a whole can be easily controlled. As an additional controllable or controllable operating means for influencing the current value of the exhaust air flow rate, the ventilation unit AA in Fig. 1 comprises a ventilation unit AG which can be advantageously controlled.

The device according to the invention for operating such a venting device comprises an electrically operated binary SE flow sensor. The flow sensor SE outputs a sensor signal SA when the flow velocity V of the exhaust air flow LS in the ventilation unit AA falls below or exceeds a predetermined lower limit. In the block diagram of Fig. 1, such a binary flow sensor SE is located in the outlet nozzle AS at the end of the exhaust air manifold AR. Preferably, for the flow sensor, the current low limit Vmin of the outflow air flow rate LS is adjustable externally. The flow sensor SE on the ML measuring line provides a binary BS sensor signal.

This BS sensor signal is applied to the SPS program-controlled computer, which is another important element of the operating device of the present invention. The SPS program-controlled computer is preferably a low-power, programmable storage controller. Depending on the actual value of the binary BS sensor signal, the SPS program-controlled computer influences the controllable or controllable actuating means of the ventilation device AA on the ML measuring line so that the flow velocity V of the exhaust air flow LS does not fall below a predetermined lower limit Vmin.

For this purpose, in the example shown in FIG. 1, the SPS program-controlled computer is connected by control SL wires to the electrically controlled shut-off valves VS1, VS2 and VS3 at the suction end of the suction ports AB1, AB2 and AB3. To this end, the SPS program-controlled computer in the example of Figure 1 is connected by an additional SM control and measurement signal line to an advantageously controllable speed AG ventilation unit.

For further explanation, in the example of Fig. 1, the implement BM1 and BM2 are in operation, and thus the electrically controlled shut-off valves VS1, VS2 are open at the respective suction nozzles AB1, AB2. In contrast, the BM3 machine is switched off and the shut-off valve VS3 is closed at the respective inlet manifold AB 3. If, in this operating state, the binary SE flow sensor detects, via an active binary BS sensor signal, that the outflow airflow V of the LS has fallen below the permissible lower limit Vmin, the SPS program-controlled computer-controlled and adjustable operating devices. In the example of Fig. 1, for example, the shut-off valve VS3 on the suction port AB3 of the currently inactive BM3 can be opened by the control provided by the control signal line SL. If this step alone is not sufficient to increase the value of the flow velocity V of the exhaust air LS, so that it exceeds the predetermined lower limit Vmin,

In the example of Figure 1, the SPS program-controlled computer is the speed of the AG ventilation unit

EN 216 518 Β increases it sufficiently through the SM control and measurement cable.

Figure 2 is a sectional view of a first preferred embodiment of a binary SE flow sensor of the operating device according to the invention. This flow sensor has a swing damper R, which is preferably located in the central AR recirculation manifold AR of the ventilation unit AA so that when there is no outflow air LS, the outflow manifold AR is almost closed in cross section and the open air flow LS is self-acting. remains. Accordingly, Fig. 2 shows the initial position P1 of the swing damper R, which closes the exhaust air collector tube AR almost completely, and the operating position P2 of the swing damper, in which an outflow of air LS keeps the swing damper open.

A stable initial position P1 at a flow rate of approximately 0 m / s can be achieved either by the deadweight of the swing damper R or by a low tensile return spring. In the example of Fig. 2, the swing damper R is disposed through a axis of rotation, preferably in a separate receiving box K, at the exhaust air outlet LE of the ventilation device AA. When the exhaust air flow LS exits, the flap R moves away from the initial position P1. Each degree of deflection of the swing damper can be assigned to a specific value of flow rate.

According to the invention, the binary flow sensor SE comprises an electrically actuated binary sensor element B which outputs a binary sensor signal BS when the flip flap P2 enters or exits the sensor detection area when open. With additional controls, the binary sensor B can be adjusted such that the flip flap R, when open, enters the sensor's detection area or exits when the flow velocity V of the outgoing air flow LS exceeds or falls below a predetermined minimum Vmin. .

In the example shown in Fig. 2, the binary sensor element B of the flow sensor SE is designed, for example, as an BERO inductive proximity switch or a photocell and recessed into a portion K of the venting apparatus AA comprising a flip-flap R. This part K may be the AR air intake manifold or a special K receiver for the swing damper. If flip-flop R is sufficiently deflected in operating position P2, that is, when airflow LS is flowing sufficiently high, flip-flop R will approach the binary sensor element B enough to reach its detection area, and the active level of the binary BS sensor signal will reach the ML measurement line. operating tool SPS program guides to your computer. In the example of Fig. 2, the sensor element B is adjusted so that its "trigger threshold" for the desired minimum flow velocity of the airflow LS is, for example,> = 20 m / s by changing the screw depth H of the sensor element B K in the wall of the wardrobe.

Preferably, the binary sensor element B is adjusted during commissioning of the actuator by, for example, measuring a different flow rate with an anemometer and determining the associated flap positions. The inclination angle of the swing damper is preferably 70 ° greater than the initial position at flow velocities equal to or greater than 20 m / s. With the help of such an anemometer, the binary sensor element B in the binary SE flow sensor of the actuator of the present invention can be easily adjusted so that the rocker damper R enters the detection area of the binary sensor element B when the lower flow velocity Vmin is reached. During this setting, the exhaust air stream is not yet loaded with solids when the ventilation unit is commissioned. Finally, in the example of Fig. 2, there is also a stop AN for limiting the opening angle of the swing damper, which also serves to mechanically protect the sensor element B which protrudes into the interior of the receiving cabinet K.

Figures 3 and 4 show a second preferred embodiment of the binary SE flow sensor of the operating device according to the invention. Figure 3 is a sectional view of a swing damper R formed in the same manner as in Figure 2. In contrast, in the second preferred embodiment shown in the view of Figure 4, the binary sensor element B of the flow sensor SE is located on the outside of the wall K of the receiving box K containing the swing damper R. In this embodiment, an indicator ST is provided which is rigidly connected to the swinging damper R, and the portion containing the swinging damper R is formed on the outer wall of the receiving cabinet K.

In the embodiment of Fig. 4, the indicator ST is formed by a marker rod which is guided through the axis of rotation TP on the wall of the receiving cabinet K and is rigidly connected to the swing damper R. Outside the receiving cabinet K, the indicating device ST makes the same movements as the swinging damper R therein, so that the desired degree of opening can be detected as in the embodiment of Fig. 2. To this end, an additional flag F is preferably provided at the head end of the beacon to cause a defined change in the active signal level of the binary BS signal when it enters the detection area of the sensor. The flag F is preferably extended in the direction of the closing flap R. In a further embodiment of Fig. 4, the binary sensor element B is displaceably disposed in the alignment arc JB on the outside of the receiver cabinet K. In this way, it is easy to fine tune the detection area of the sensor and the current deflection of the swing damper R and its associated ST indicator.

Vibration of the swing damper, which can be caused, for example, by bumps of larger solids, can be prevented or rendered ineffective by mechanical damping of the swing damper or by electrical filtering of the binary BS sensor signal. For this purpose, in the block diagram of FIG. 1, an ML filter line F between the flow sensor SE and the SPS prog4 controlled computer has an additional filtering device F, e.g. The filtering apparatus F may also be implemented as software in a SPS program-controlled computer. The filtering apparatus F of the present invention delays by at least one change of the binary BS signal from the active signal level, which indicates that the current flow rate V has exceeded the lower limit, to an inactive signal level by an adjustable TF filtering time, indicating that the inactive signal level the current flow rate V has dropped below the lower limit. This is illustrated in more detail by the example of the following Figures 5 and 6.

Figure 5 shows an exemplary evolution of the binary BS signal. Here, for example, the signal level at time S1 changes from the inactive signal level 0 to the active signal level 1. The pivoting damper thus entered the detection area of the yeast element, indicating that the current flow rate exceeded the lower limit as desired. At point S2, the outgoing air flow rate again drops below the lower limit so that the binary BS sensor signal switches from the active signal level to the inactive signal level 0. Figure 6 below illustrates the corresponding evolution of the sensor signal BS at the output of a filter apparatus F. It can be seen that the signal change from 1 to 0 is transmitted only after the filtering time TF has elapsed.

At time S3, the sensor signal BS briefly switches to active signal level 1 again, and at time S4, it drops again to inactive signal level 0. The evolution of the filtered sensor signal below shows that the transition from the inactive signal level to the active signal level is transmitted at time S3 without filtering, while the drop to the inactive signal level at time S4 appears only after the filtering time TF has elapsed. This function of the filtering apparatus F has the advantage that the transient deflections of the swinging damper, which are caused, for example, by the cracking of solid particles, can be suppressed by the binary sensor signal. This is clearly seen at the right of Figures 5 and 6. Figure 5 illustrates short-term successive transitions of KP between the levels of the binary sensor signal. These oscillations are not mapped to the filtered binary sensor signal which maintains the active signal level 1 as shown in FIG. 6 below. Thus, the filtered BS sensor signal at time S5 in FIG. 6 follows the transition from the inactive signal level to the non-active signal level. The downturn to the inactive level immediately after S6 is suppressed by the TF filtering time course in the signal of FIG. The downturn is ineffective because in Fig. 5, the sensor signal returns to the active signal level 1 at time S7 before the filtering time TF has expired.

Thus, transient transitions of the binary sensor signal from the active signal level to the inactive signal level are suppressed by the filtering apparatus F. As a result, the controllable or controllable actuators of the ventilation device do not cause disturbing short circuits due to the SPS program controllers computer of the actuator of the present invention.

Fig. 2-4 of the binary SE flow sensor. In particular, the non-return flap at the end of the venting device AA, in many cases at the outlet air outlet LE, is particularly advantageous as a swing damper. The device according to the invention thus makes it possible in a simple and robust manner to continuously monitor the flow rate of the outflow air in order to comply with a lower limit. The unit can be cheaply installed and, if necessary, can be retrofitted to existing ventilation units at no additional cost.

Claims (11)

PATENT CLAIMS An apparatus for operating a ventilation device comprising controllable or controllable operating means for controlling the flow rate of an outflow air stream, comprising: (a) a binary flow sensor (SE), which provides a binary signal when the electrically operated flow rate (V) of the exhaust air stream (LS) in the ventilation unit (AA) falls below or exceeds a predetermined lower limit (Vmin); (b) a program controlled computer (SPS) connected to the binary flow sensor (SE), in particular a programmable storage controller, having at least the binary sensor signal (BS) of the binary flow sensor (SE) and controlling the outgoing air flow; the outputs of the exhaust air flow (LS) which prevent the flow rate from falling below the predetermined lower limit (Vmin) are routed to the operating means of the ventilation unit (AA). Device according to Claim 1, characterized in that the ventilation device (AA) comprises a ventilation unit (AG) for generating an outflow air stream (LS) as a controllable or controllable operating means, to which signals from a program-controlled computer (PSP), in particular switch-off signals and / or speed control signals are provided. Device according to Claim 1 or 2, characterized in that the ventilation device (AA) comprises electrically controlled shut-off valves (VS1, VS2, VS3) connected to suction nozzles (AB1, AB2, AB3) as controllable or controllable operating means, which preferably, they are located at the suction side ends thereof and on which are programmed computer (PSP) signals, in particular open and close signals (SL). 4. A device according to any one of claims 1 to 3, characterized in that the binary flow sensor (SE) comprises a sub) in the absence of an exhaust air stream (LS) located in the central exhaust air manifold (AR) of the ventilation device (AA); that is, in the initial position (P1), and in the case of the exhaust air flow (LS), the swing damper (R), which is automatically open, ie in operating position (P2), is electrically actuated when the swing damper (R) is open; a binary sensor element (B), which emits a binary sensor signal (BS) when entering or exiting the sensor detection area, and in particular a photocell or an inductive proximity switch; and a3) entering or exiting the sensor detection zone to adjust the binary sensor element (B); air flow (LS) flow rate vocal adjustment device to a predetermined lower limit (Vmin). Device according to Claim 4, characterized in that the binary sensor element (B) of the flow sensor (SE) is embedded in a part of the ventilation device formed as a receiving cabinet (K), in particular in a supply air collection pipe (AR). 6. A device according to claim 4, characterized in that (a) the binary sensor element (B) of the flow sensor (SE) is disposed on the outside of the wall of the section containing the swing damper (R), which is formed as a receiving cabinet (K), and b) comprising a signaling device (ST) which is rigidly connected to the swing damper (R) and is led to the outside of the wall of the part containing the swing damper (R), which is formed as a receiving cabinet (K). Apparatus according to claim 6, characterized in that the indicating device (ST) is formed by a marker connected to the axis of rotation (DP) of the swinging damper (R) having a flag (F) at its head end. Device according to Claim 6 or 7, characterized in that it comprises an adjustment curve (JB) on which the binary sensor element (B) is slidably placed. 9. Device according to any one of claims 1 to 3, characterized in that the active signal level (1) below the binary flow sensor (SE) at the current flow rate (V) above the lower limit (Vmin) of the binary sensor signal (BS) is the lower limit (Vmin). A filtering device (F) delaying at least one change of the filtering time (TF) to an inactive signal level (0) at the current flow rate (V), which is lower than 1V, is provided. Apparatus according to claim 9, characterized in that the filtering device (F) is integrated into the program-controlled computer. 11. Device according to any one of claims 1 to 3, characterized in that the non-return valve at the end of the ventilation device (AA) at the exhaust air outlet (LE) serves as a swing damper.