DE2700928A1 - ACTUATOR FOR AIR AND THROTTLE VALVES, MIXING TAPS AND THE LIKE. IN HEATING AND VENTILATION SYSTEMS - Google Patents

Description

Actuator for air and throttle valves, mixer taps and the like in heating and ventilation systems

The invention relates to an actuator for air and Throttle valves, mixer taps and the like in heating and ventilation systems, which is designed as an electric motor with gear and on a flap or. Acts valve axis.

Actuators of the type mentioned at the beginning are known become, in which the gear motor is connected to one of his Housing protruding axis produces a rotating movement, which is transferred to a flap or valve axis by means of joints and rods.

There is also an actuator known that hydraulically or works pneumatically and generates a pushing movement by a piston, which is via a linkage with joint and levers e.g. transferred to an air damper axis

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will. The pushing movement can also be generated by a gear unit and a threaded spindle.

The known designs have the disadvantage that the power transmission to the axis of rotation is only indirect. With the piston principle, the full lifting force can only be used if the lever arm on which the piston rod is attached attacks, is exactly perpendicular to the piston rod. However, this only applies to a single position to. In all other positions the angle of the direction of force on the lever is such that the effective force component is smaller than the Schubkriut. The transfer is also not linear. In the case of the rotation principle mentioned first, this phenomenon is compensated for in the effect by the same Angle between the lever on the motor and the linkage compensates for the lack of linearity. However, the Forces on the linkage are very large, so that the joints, which are generally designed as simple ball joints Due to their low level of efficiency, they reduce the power transmitted and are easily damaged.

The object of the invention is to create an actuator that is simple to manufacture and easy to assemble works with good efficiency.

This object is achieved according to the invention in that the last transmission gear is provided with a hollow axle and is plugged directly onto the flap or valve axis to be driven.

The actuator can therefore, for example by the hollow axle 3 rigidly connected to the axle to be driven, of the axis to be driven be carried and with stationary Parts should only be connected to prevent rotation.

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Da3 gear of the last gear stage is preferably used as Segment formed, since an angle of rotation of Q0 to 105 ° is generally sufficient. To limit this angle of rotation one or two fixed or adjustable stops are preferably used. By suitable choice of the electric motor and the gearbox is designed accordingly, the motor can remain energized even when the end position is reached. This has the advantage that on the one hand the regulation or control is simplified and on the other hand a Spring element can be present that guides the axis into a defined position when the motor is switched off. the The motor is switched off, for example, in the event of a power failure or when the entire heating system is switched off Ventilation system. The flap or the valve is then brought into a defined safety position by the peder element, whereby safety conditions can automatically be met in the event of cheers, risk of fire or the like.

According to a further feature of the invention, the power transmission from a reversible drive, which contains a synchronous electric motor with gear, to air dampers, Throttle valves, mixer taps or the like, the end positions of which are defined by mechanical stops or the like, via a torque-limiting clutch take place. When air conditioning buildings, especially with so-called parapet or ceiling units, the heat or Cooling energy primarily metered through air flaps. These air flaps are adjusted by actuators, which in turn receive the control signal from temperature controllers, either as pneumatic or electrical ones Signals. A room to be air-conditioned usually needs multiple devices. However, all devices in the same room must be controlled by the same controller,

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otherwise there is a risk that energy losses will occur due to mutual influences (e.g. simultaneous Heating and cooling). However, the flaps must run as parallel or synchronously as possible.

This synchronous operation is possible with pneumatic drives. In the case of electric actuators, the synchronous operation is after achieved in two different ways in the prior art. By scanning the flap position e.g. by means of a potentiometer coupled to the flap is controlled by a so-called control relays in each individual actuator, the damper position is compared with the controller signal and at Corrected needs. This method is structurally very complex. Another method is that in the actuators Synchronous motors are used. These synchronous motors enable very good synchronous operation. Reversible Synchronous motors require a capacitor that is matched to the motor to generate a rotating field. As soon as the actuator has reached an end position, it must go through suitable means are completely separated electrically from the other motors, because otherwise it would be uncontrolled by reverse currents Executes movements and in turn affects the other motors and disrupts synchronous operation. Serve electrical Separation cannot be achieved with Reluis because of their differences the Synchroni.'Mif of the drives. Either a more genuine synchronization must be accepted or it is so-called separation electronics are necessary, which in turn is expensive. For this reason, the pneumatic control has hitherto been used Often preferred to electrical control.

By dan Qg. According to the invention, it is now possible, in a simpler way ^{, to operate the actuators for several flaps, valves, etc.} electrically synchronously and thus to be able to utilize the basic advantages of electrical control.

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After reaching one of the two end positions, the torque is limited by the coupling without the motors have to be switched off and influence each other.

The clutch can be designed so that the same maximum torque is always transmitted. This is possible. It has also been found that the service life of the clutch can cope with continuous operation is. Different types of couplings are possible. The version with the intermediate coupling is Also conceivable with actuators, which are, for example, on threaded spindles for actuating flap or valve axes act.

Further preferred features of the invention emerge from the claims and the description in connection with FIG Drawing. Embodiments of the invention are shown in the drawing and will be described in more detail below explained. Show it:

Fig. 1 is a front view of an actuator according to the invention with part of an air flap,

Pig. 2 shows a side view of FIG. 1,

Fig. 3 is a side view of another embodiment
and

FIG. 4 shows an enlarged part from FIG.

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In the pig. 1 and 2, an actuator 11 is shown, which drives the axis 12 of an air damper 13 for heating or ventilation systems. The actuator 11 has a Base plate 14, to which a gear bridge 15 is attached parallel at some distance. This carries an electric motor 16, the shaft of which drives a gear reduction gear 18 via a pinion 17. It contains im illustrated example two gear / pinion combinations 19 »20. The last pinion 21 is in mesh with one Toothed segment 22 of relatively large diameter, for example 150 mm. Since usually only an angle of rotation between 90 and 105 is required, it also includes only this angle. It is mounted on the base plate 14 and has a hollow axis firmly connected, which in the example shown is screwed or welded to the tooth segment Socket is formed. The axis 12 of the air flap protrudes through the hollow axis and is over the screws 24 firmly connected to the hollow axle and thus the toothed segment.

The pivot angle of the tooth segment 22 is set by a stop 25 which runs in a slot in the segment limited to a defined angle between 90 and 150 °. From Pig. 1 can be seen a lever 26, which is by a Spring 27 is loaded counterclockwise.

The assembly of the actuator is extremely easy. It is plugged onto the axis 12 with its hollow axis 23 and is carried by the axle 12. It is only by a screw 28 in the opposite axis 12 End of the base plate 14 secured against rotation. The axis 12 also protrudes through the base plate 14 and is mounted in this indirectly via the hollow axis 23, so that the actuator can be positioned anywhere on the valve axis can be attached.

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The toothed segment 22 is via the electric motor 16 and the reduction gear 18 optionally driven in one direction or the other. The motor is dimensioned in such a way that that it can remain under tension even when the end position is reached. In the event of a power failure, the spring pulls 27, via the lever 26, moves the air flap 13 into a defined end position limited by the stop 25.

Due to the type of flap drive according to the invention become the disadvantages of complicated power transmission avoided by means of rods, ball joints and flap levers. In addition, the maximum Transfer torque without loss of linkage. The last stage of the transmission leaves at a radius of for example 75 mm of the segment 22 to a very large translation of for example 10: 1. As a result, the forces to be transmitted through the teeth are relatively small. Pur is the setting of a torque of 1.5 mkp this version requires a tangential force of only 20 kp on the teeth of the last gear stage. This means that inexpensive manufacturing methods are available for the gears, for example punching, possible. The transmission can be constructed simply and easily. The time consuming Assembly of flap consoles, rods, ball joints and flap levers with the appropriate Alignment and adjustment are not required.

Another embodiment is shown in FIGS. Identical or similar parts are given the same reference symbols. The actuator 11 carries on its base plate 14, the motor 16. The reduction gear 18 is located between the base plate 14 and the gear bridge 15 stored, which in turn consists of the drive pinion 17 and two gear / pinion combinations 19,20. The pinion 21

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of the last transmission wheel 20 is engaged with a strong gear 30 with a large diameter which is rotatably mounted on a sleeve 31. The combination of gear / bush 30, 31 is designed as a mechanical slip clutch, as indicated in FIG. 4 on a larger scale. The spur gear 30, designed as a ring, sits slidingly on the hub 31. At the side, prestressed steel disks 32 are riveted firmly to the hub 31 on their inner circumference. On the outside, the steel disks 32 press with a defined force on the gear wheel 30, which is advantageously made of a plastic whose static friction is not or only insignificantly greater than the sliding friction. The pretensioning of the steel disks is selected so that the frictional force resulting from the pressure of the steel disks 32 on the gear 30 under the static or sliding friction coefficient of the two surfaces meeting one another corresponds to the desired maximum transmission force. The frictional force acting per unit area is selected so that it does not exceed a certain level in order to avoid excessive heating or premature wear in continuous operation. These conditions are met, for example, by an advantageous embodiment in which the hub has an outside diameter of 16 mm and the friction disk 32 has a thickness of 0.3 mm and a preload of 0.5 mm for diameters of 26 mm outside and 14 mm inside. With a spur gear of 29 »5 mm pitch circle diameter and a total line
achieved.

A total friction surface of 80 mm results in a torque of 1.5 cmkp

In the example according to FIGS. 3 and 4, the hub 31 is rotatably mounted in the two plates 14 and 15 and is on its inside an axially extending toothing into which

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a corresponding toothing of the axle 12 engages. The attachment of the bushing on the axle can, however can also be done differently, for example by means of tongue and groove or, as in the example described above, by clamping o. The like. It is also possible to give the socket an internal thread. In this case the axle would be used as a traction and pressure spindle formed.

The motor is a reversible synchronous electric motor, and preferably in the manner of a capacitor two-phase alternating current motor educated. When a flap driven by the axis 12 its by a mechanical Stop, which in the present case is formed by the air flap itself, has reached the limited end position, so increase it The counterforce increases the torque in the transmission until the gear wheel 30, hub 31 and friction disks Coupling 33 formed 32 slips. Through this execution of the actuator with torque-limiting coupling, limit switches are not required. It becomes an actuator created, which can be installed in the simplest way without setting travel-dependent limit switches Need to become. Above all, it is possible to have other drives operated in parallel from the same controller, without the motors influencing each other due to the parallel connection of the reversible capacitor motors. By starting the coupling against the end stops, for example by the closing Flaps can be formed, the motors connected in parallel and thus the air flaps always synchronized anew in their position. In this version, too, the current is required when the end position is reached not to be switched off, so that expensive feedback systems are not required.

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Claims (13)

A 16 308 - MC - Expectations M. Actuator for air and throttle valves, mixer taps and the like in heating and ventilation systems, which is designed as an electric motor with gear and acts on a flap or valve axis, characterized in that the last transmission gear (22, 30) provided with a hollow axle (23, 31) and directly on the flap or valve to be driven. Valve axis (12) is inserted. 2. Actuator according to claim 1, characterized in that the angle of rotation of the last gear (22) through End stops (25) is limited. 3. Actuator according to claim 2, characterized in that the angle of rotation is limited to 90 to 105 °. 4. Actuator according to one of the preceding claims, characterized in that the motor (16) such is designed and dimensioned so that it remains switched on even after reaching the end stops (25) can. 5. Actuator according to one of the preceding claims, characterized in that the gear wheel (22) as a segment is trained. 6. Actuator according to one of the preceding claims, characterized in that a spring element (10) is provided is that when the motor (16) is switched off, the axis (12) moves into a defined position. - 11 - 709829/0921 ORIGINAL INSPECTED 27-0928 A 16 308 7. Actuator according to one of the preceding claims, characterized in that the last Gear stage (21, 22) has a very high reduction ratio and the rest of the gear (17, 19 »20) is to be designed for a low load. 8. Actuator according to one of the preceding claims, characterized in that it is of the to be driven axle (12) is carried and with stationary parts only to prevent rotation (18) is connectable. 9. Actuator, in particular according to one of the preceding claims, characterized in that the power transmission from the drive, which is a reversible synchronous electric motor (16) with gear (18) contains, to the air and throttle valves (13), mixer taps o. The like., Whose end positions by mechanical Stops or the like are defined, takes place via a torque-limiting clutch (33). 10. Actuator according to claim 9, characterized in that the mechanical stops on the flaps, valves or their axes are provided. 11. Actuator according to claim 9 or 10, characterized in that the torque-limiting clutch (33) is designed as a mechanical Priktionskupplung. 12. Actuator according to one of claims 9 to 11, characterized in that several with capacitor synchronous motors (16) equipped actuators (11) are electrically connected directly in parallel. - 12 - 703829/0 ^ 2 1 27-0928 A 16 308 13. Actuator according to one of claims 9 to 12, characterized in that several flaps (13), Taps or the like driven by actuators (11) with motors connected electrically in parallel are, can be automatically synchronized by their stops. 7 0 "° 29/0921