Torque test sensor for electric valve actuator

Abstract

The utility model relates to the technical field of valve control devices, in particular to a torque test sensor for an electric valve actuator, which is mounted on the outer wall of a machine body of a test device for the electric valve actuator and comprises four resistance strain gauges. The included angles between the directions of the resistance strain gauges and the transmission shaft of the testing device of the valve electric device are positive 45 degrees and negative 45 degrees, the four resistance strain gauges are connected in series to form a bridge, one group of opposite sides of the bridge is positive 45 degrees, the other group of opposite sides of the bridge is negative 45 degrees, and a direct-current power supply is applied to vertexes of two opposite angles of the bridge; and voltage signals are output at the other two diagonal vertexes of the bridge. A new thought is adopted, according to the Newton's law, acting force and counter-acting force are equal in magnitude and opposite in direction, the resistance strain gauges are not attached to the rotating shaft or attached to the external machine body, the electric bridge is directly connected with the circuit board, transmission is not conducted through a sliding ring or wireless, and therefore the measuring precision is improved, and faults are reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of valve control devices, and particularly relates to a torque test sensor for a valve electric device. Background Art

[0002] At present, there are two main categories of torque sensors commonly used for valve electric devices:

[0003] One category is that resistance strain gauges are pasted on the outer circumference of the torque test drive shaft (rotating shaft), and the directions of the strain gauges form an angle of +45 degrees and -45 degrees with the drive shaft. Four strain gauges are connected in series to form a "bridge". The opposite sides of the bridge are at +45 degrees, and the other two sides are at -45 degrees. The four vertices of the bridge are connected to an electrical signal through slip rings.

[0004] The other category is that resistance strain gauges are pasted on the outer circumference of the torque test drive shaft (rotating shaft), and the directions of the strain gauges form an angle of +45 degrees and -45 degrees with the drive shaft. Four strain gauges are connected in series to form a "bridge". The opposite sides of the bridge are at +45 degrees, and the other two sides are at -45 degrees. The four vertices of the bridge are connected to a circuit board fixed on the drive shaft. The circuit board receives a wireless signal from an external circuit board, converts this signal into a DC power supply, provides it to the bridge, and the output signal of the bridge is converted into a wireless signal through the circuit board on the rotating shaft and supplied to the external circuit board to achieve torque measurement.

[0005] For the first type of the above sensors, since slip rings are used to transmit electrical signals, the slip rings themselves have contact resistance, which affects the measurement accuracy.

[0006] The second type has a complex structure, many circuit components, and many possible faults. Content of the Utility Model

[0007] Aiming at the problems existing in the prior art, the utility model provides a torque test sensor for a valve electric device with a simple structure, high precision, and low failure rate.

[0008] The utility model is implemented as follows:

[0009] A torque test sensor for a valve electric device, the torque test sensor is installed on the outer wall of the body of the test device of the valve electric device, and includes four resistance strain gauges pasted. The directions of the respective resistance strain gauges form an angle of +45 degrees and -45 degrees with the drive shaft of the test device of the valve electric device. The four resistance strain gauges are connected in series to form a bridge. One set of opposite sides of the bridge is at +45 degrees, and the other set of opposite sides is at -45 degrees. A DC power supply is applied to two of the diagonal vertices of the bridge, and a voltage signal is output at the other two diagonal vertices of the bridge.

[0010] Preferably, the DC power supply is a 3V or 5V DC power supply.

[0011] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0012] The utility model adopts a new idea. According to Newton's law, the acting force and the reaction force are equal in magnitude and opposite in direction. In the utility model, the resistance strain gauges are not attached to the rotating shaft but to the external body. The bridge is directly connected to the circuit board without passing through a slip ring or wireless transmission, thereby improving the measurement accuracy and reducing faults. Description of the Drawings

[0013] Figure 1 is a schematic structural diagram of the torque test sensor of the valve electric device of the utility model;

[0014] Figure 2 is an unfolded view of each resistance strain gauge attached to the utility model;

[0015] Figure 3 is a connection schematic diagram of each resistance strain gauge attached to the utility model. Detailed Embodiment

[0016] In order to further understand the content, features and effects of the utility model, the following embodiments are listed and described in detail with reference to the drawings as follows.

[0017] The structure of the utility model will be described in detail below with reference to the drawings.

[0018] As Figures 1-3 shown, a torque test sensor of a valve electric device, the torque test sensor is installed on the outer wall of the body 1 of the test device of the valve electric device, and includes four resistance strain gauges 3 attached. The directions of the resistance strain gauges 3 are at positive 45 degrees and negative 45 degrees with respect to the transmission shaft 2 of the test device 1 of the valve electric device. The four resistance strain gauges 3 are connected in series to form a bridge. The four diagonal vertices of the bridge are A, B, C, and D respectively. One set of opposite sides of the bridge is at positive 45 degrees ( Figure 3 the AD and BC opposite sides in Figure 3 ), and the other set of opposite sides is at negative 45 degrees (

[0019] the AB and AC opposite sides in

[0020] ). A DC power supply of 3V or 5V is applied to two of the diagonal vertices A and C of the bridge, and voltage signals are output at the other two diagonal vertices B and D of the bridge and provided to a dedicated circuit to display the torque value output by the valve electric device.

[0020] The basic principle, main features and advantages of the present utility model have been shown and described above. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and all these changes and improvements fall within the scope of the present utility model claimed.

Claims

1. A torque test sensor for a valve electric device, characterized in that: The torque test sensor is installed on the outer wall of the body of the test device of the valve electric device, including four resistor strain gauges, each of which is at an angle of positive 45 degrees and negative 45 degrees to the transmission shaft of the test device of the valve electric device. The four resistor strain gauges are connected in series to form a bridge, one group of opposite sides of the bridge is positive 45 degrees, and the other group of opposite sides is negative 45 degrees. A DC power supply is applied to two of the diagonal vertices of the bridge, and voltage signals are output at the other two diagonal vertices of the bridge.

2. A torque test sensor for a valve electric device as claimed in claim 1, characterized in that: The DC power supply is a 3V or 5V DC power supply.

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