RU210459U1 - Electromechanical device for limiting torque in the electric drive of shut-off valves - Google Patents

Abstract

The utility model relates to pipeline valves and can be used to control shut-off valves equipped with electric drives. An electromechanical torque limiting device in an electric drive of shut-off valves contains a housing and a gearbox, one of the links of which is fixed against an elastic element to prevent rotation around its axis and is made with the ability to rotate this link around its axis and turn off the power supply of the electric drive as a result of this rotation at a limited torque, while the gearbox is a wave gearbox with intermediate rolling elements, containing an input rim, intermediate rolling elements, a generator and an output shaft - separator, fixed from rotation the link is the generator. The technical result is an increase in the reliability of the electromechanical torque limiting device with an increase in the maximum torque of the electric drive.

Description

The utility model relates to pipeline valves and can be used to control valves equipped with electric drives.

With a sharp braking of the valve valve, which occurs at the moment the valve reaches the extreme positions or emergency jamming during the movement of the valve to open or close, the torque on the output shaft of the electric drive increases due to the use of the kinetic energy of the electric motor rotor. Torque limitation by switching off the motor at a certain torque value prevents damage.

An electromechanical device for limiting torque in an electric drive of shutoff valves, adopted as a prototype, is known (RF patent No. 143478 for a utility model, publication 27.07.2014, IPC F16K 31/04), including a housing and a planetary gearbox containing an input central wheel, satellite, engaged with it, the carrier, fixed from rotation by an elastic element (compression spring) with the possibility of turning the carrier and disconnecting the power supply of the electric drive as a result of this rotation at a limited torque. In addition, the planetary gearbox contains an additional planet gear fixedly and coaxially connected to the first planet gear, having a different number of teeth, as well as an output central gear engaged with the additional satellite gear. When the electric motor of the electric drive is turned on, the input central wheel kinematically connected to the output shaft of the electric motor transmits rotation to the first satellite and additional satellite and further through the satellites and to the output central wheel kinematically connected to the input link of the electric drive transmission mechanism. In the event that a torque equal to the limited value occurs in the transmission mechanism of the electric drive, at which the output central wheel stops rotating, the rotation from the input central wheel through the satellites is transferred to the carrier. The carrier turns, deforms the elastic element (compression spring) and moves the rod longitudinally, spring-loaded by the compression spring. With the longitudinal movement of the spring-loaded rod, the nut located at its end will press the lever (button) of the electric motor switch and stop the operation of the electric drive.

The analogue has the disadvantage that during operation the satellites are affected by an uneven load due to errors in the manufacture and installation of parts and leading to premature disruption of the normal operation of the torque limiting device in the shutoff valve electric drive. The disadvantage is also the impossibility of increasing the maximum torque on the output shaft of the torque limiter without increasing the overall dimensions and, accordingly, the mass of the planetary gear in the torque limiter.

The technical objective of the utility model is to create a torque limiting device that allows increasing the maximum torque without increasing the dimensions of the electric drive.

The technical result achieved in the implementation of the proposed technical solution is to increase the reliability of the electromechanical torque limiting device in the electric drive of shut-off valves with an increase in the maximum torque of the electric drive.

The technical result is achieved by the fact that the electromechanical torque limiting device in the shutoff valve electric drive contains a housing and a gearbox, one of the links of which is fixed against the elastic element to prevent rotation around its axis and is configured to rotate this link around its axis and turn off the power supply to the electric drive as a result of this rotation at a limited torque, while the gearbox is a wave gearbox with intermediate rolling elements, containing an input rim, intermediate rolling elements, a generator and an output shaft - separator, the link fixed from rotation is the generator.

Compared to the planetary gear of the prototype, the wave gearbox with intermediate rolling elements provides a large torque with a minimum number of gear stages (2-3 stages). Since the dimensions of the wave reducer with intermediate rolling elements increase slightly with an increase in the maximum torque for which it is designed, the proposed electromechanical torque limiting device will also have smaller dimensions for large torques compared to the electromechanical torque limiting device, which uses planetary gear according to the prototype.

For a better understanding of the essence of the claimed utility model, graphic materials that do not limit the essence of the utility model are presented below, where:

figure 1 shows a longitudinal section of the electromechanical device for limiting torque in the actuator valves;

figure 2 shows a section A-A from figure 1;

figure 3 shows an enlarged view B of figure 2.

The electromechanical device is designed to limit the torque in the electric drive containing the electric motor 1 (figure 1) and the transmission mechanism 2 (figure 1), the input link of which is shown by position 3 in figure 1.

The inventive device includes a housing 4 (figure 1, 2), which has a wave gear with intermediate rolling elements, containing the input crown 5 (figure 1), intermediate rolling elements (rollers) 6 (figure 1), generator 7 (figure 1). .1), output shaft - separator 8 (Fig.1). The input ring 5 is connected to the rotor of the electric motor 1. The gear 3 of the output shaft - separator 8 is the input link of the transmission mechanism 2. The generator 7 is fixed against the elastic element 9 (figure 2) to prevent rotation around its axis with the possibility of turning the generator 7 around its axis and turning off the power supply of the electric drive as a result of this rotation at limited torque.

The inventive device is installed between the electric motor 1 of the drive and its transmission mechanism 2, while the input ring 5 is kinematically connected to the electric motor 1, and the gear mounted on the output shaft - the separator 8 - with the input link of the transmission mechanism 2 of the electric drive.

The elastic element 9 is mounted with support on the housing 4 and against the clamp 10 (figure 2) attached to the generator 7. The modulus of elasticity of the element 9 is chosen in such a way that, with a limited torque, the generator 7 would deform the element 9, turn and due to its turn initiated a power outage to the drive.

A compression spring can be used as the elastic element 9. Inside the spring 9 there is a rod 11 (figure 2) with the possibility of longitudinal movement when turning the generator 7 under the action of a limited torque. The rod 11 can rest with one end against the stop of the clamp 10 in the direction that prevents the rotation of the generator 7 when the electric motor 1 is turned on. clamp 10. The end of the spring 9, facing the stop of the clamp 10, rests on the protrusion on the rod 11. The opposite end of the spring 9 rests on the housing 4. To control the torque value at which the electric motor 1 must be turned off, the second end of the rod 11 has screw 13 (figure 2) with a nut 14 (figure 2) installed with the possibility of changing its position on the screw 13. The screw 13 can be made hollow, loosely seated at the end of the rod 11 with the possibility of rotation and secured from longitudinal movement along the rod 11 using the protrusion 15 (figure 2) on the rod 11 and the retaining ring 16 (figure 2). The nut 14 is secured against rotation due to the protrusion 17 (figure 2) made on the nut 14 and sliding in the longitudinal groove on the sleeve 18 (figure 2) fixedly attached to the body 4. The nut 14 is installed in such a way that it can act on the lever switch 12 of the electric motor 1 when turning the generator 7 and turn off the power supply of the electric motor 1. When the screw 13 is rotated, the nut 14 moves along it, approaching or moving away from the switch 12. Thus, the degree of deformation of the elastic element 9 (spring) decreases or increases accordingly and, therefore, decreases or the limited torque increases. On the sleeve 18 there is a torque setting scale 19 (figure 3). To set the limited torque, the mark on the nut 14 is combined by turning the screw 13 with the mark of the torque value on the scale 19.

To stop the rod 11, spring-loaded by the spring 9 on the generator 7 can be fixed clamp 10 with a ledge 20 (figure 2).

For the operation of the claimed device in conditions of changing the direction of rotation (reverse) of the electric motor 1, a second elastic element 9 is provided, for example, a spring mounted on the other side of the protrusion 20 of the clamp 10 fixed on the generator 7.

The device works as follows.

When the electric motor 1 of the electric drive is turned on, the crown 5, which is kinematically connected to the output shaft of the electric motor 1 (in a specific version, the crown 5 is installed on it), transmits rotation through the rollers 6 to the output shaft - separator 8, which is kinematically connected to the input link of the transmission mechanism 2 of the electric drive (in a specific gear 3 mounted on the output shaft - separator 8 is kinematically connected to the gear wheel of the input shaft of the transmission mechanism 2).

In the event of a torque in the transmission mechanism 2 of the electric drive equal to the limited value at which the output shaft of the separator 8 stops rotating, the rotation from the crown 5 through the rollers 6 is transmitted to the generator 7, which rotates in the bearings 21 (figure 1) fixed in the housing 4. When turning the generator 7, the protrusion 20 of the clamp 10 deforms the elastic element 9 (compression spring) and moves the rod 11 longitudinally. When the spring-loaded rod 11 moves longitudinally, the nut 14 located at its end will press the lever (button) of the switch 12 of the electric motor 1 and stop the drive.

Thus, the uniformity of loading of the gear elements contributes to an increase in the durability and operational reliability of the proposed torque limiting device. The inventive design also provides increased torque operation in a very compact manner without destroying the components of the electromechanical torque limiting device.

Claims (1)

An electromechanical device for limiting torque in an electric drive of shutoff valves, including a housing and a gearbox, one of the links of which is fixed against an elastic element to prevent rotation around its axis and is configured to rotate this link around its axis and turn off the power supply to the electric drive as a result of this rotation when limited torque, characterized in that the gearbox is a wave gearbox with intermediate rolling elements, containing an input rim, intermediate rolling elements, a generator and an output shaft - separator, while the link is fixed from rotation is the generator.

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