Angle sensor

Abstract

FIELD: measuring equipment.SUBSTANCE: invention is intended for measuring angles during automation of CNC machines and for studying the mechanics of human movement. An angle sensor, containing a screw with a fixed beam and a nut with a movable beam, a fixed beam with a monolithic bridge of semiconductor strain gauges, with a force-input unit, is characterized by the fact that the fixed beam is made integral with the screw in the form of a cup, inside which the beam is attached to the bottom, and the force-input unit rests on an annular step made on the bottom of the nut. In this case, when the nut moves along the screw thread, the force-input unit moves synchronously with it, which leads to deformation of the beam with a monolithic bridge of semiconductor strain gauge. A monolithic bridge of semiconductor strain gauges is fixed on the back side of the beam near its termination, the leads from it are soldered to the contacts of the transition board fixed next to the monolithic bridge of semiconductor strain gauges, on the other side the leads of the “ПЭКФ”-0.1 wire are soldered to the board, passing through the hole in the bottom of the screw and then designed as a microcable laid in the groove.EFFECT: possibility of manufacturing reliable and inexpensive low-height angle sensors capable of operating in harsh conditions and measuring angles in the ranges ±165° and ±330°.3 cl, 3 dwg

Description

[0001] The invention relates to measuring equipment and is intended for measuring angles in CNC machines, robotics and measuring angular parameters of human movement.

[0002] Angle sensors (hereinafter referred to as ATS) are known to use various measurement principles. These ATS are complex to manufacture and expensive. Potentiometric ATS are widely used, but due to their low reliability and accuracy, they are unsuitable for use in harsh environments subject to impact, vibration, etc. [1].

[0003] The well-known strain gauge method appears to be a promising basis for measuring angles, as it is more reliable, accurate and cheaper.

[0004] The closest in technical essence to the proposed method is D, described in RU Patent No. 2860158, BI No. 1 [2]. Here, the beam's displacement is transmitted via a force-input unit (FIU) from a cup-shaped nut, to which the beam (B) with a monolithic strain gauge bridge (MMG) is attached. Considering that the nut rotates during angle measurements, the measuring cable connected to the connector attached to the nut will also rotate and, in doing so, additionally swing, leading to a decrease in cable reliability and the reliability of angle measurements.

[0005] The objectives of the invention are: to create a reliable, simple in design, inexpensive remote control capable of operating in harsh conditions.

[0006] The stated objectives are achieved by the fact that B is fixed on the bottom of the screw, and the SU rests on the step on the bottom of the nut and when it moves along the screw thread, the SU moves synchronously with it, which leads to the deformation of B and MMT; and by the fact that MMT is fixed on the back side of B near its termination, the leads from it are soldered to the contacts of the transition board fixed next to MMT, on the other side, the leads of the PECF-0.1 wire are soldered to the board, passing through the hole in the bottom of the screw, and then designed as a microcable laid in a groove of depth h2, width b1, connecting this hole with the hole for the connector, which is fixed on the fixed beam from the front side, the ends of the microcable wires are connected to it by soldering; and also by the fact that in a nut with an outer diameter D1, on its bottom with a diameter D2, an annular step of height h1 is formed as a single unit between the diameters d1 and d2, which, when the nut rotates, moves vertically and, at the same time, presses on the SU, which causes deformation of the B and MMT.

[0007] The description and essence of the invention are as follows. To measure an angle in biometrics, for example, when moving an arm, a fixed beam is fixed to the upper arm, and a movable beam is fixed to the elbow.

[0008] When the hand moves, the angle φ will change, the nut will rotate and move vertically, the power unit will also move, and the beam and MMT will be deformed, as a result, an electrical signal proportional to the measured angle φ will be generated on the output diagonal of the bridge.

[0009] Two limiters serve to restrict the nut's movements beyond the permissible limits: a clamp to prevent upward movements, and a support washer to prevent downward movements.

[0010] Fig. 1 shows a section of the proposed D along A-A, where the fixed beam is made integral with the screw in the form of a cup, inside which the sealing unit B is attached to the bottom, and its SU rests against the annular step of the nut bottom with an external D1 = 36 mm; two nut travel limiters, a microcable laid in a groove and a connector on the fixed beam are also visible. Fig. 2 is a view of the D from above, a cutout is made to show the beam fixed to the bottom of the screw. Fig. 3 is a view along arrow B onto the groove with a cable laid in it.

[0011] The following designations are used in the figures: 1 - screw M 30x0.5 with a fixed beam; 2 - a movable beam connected to a nut M 30x0.5 and an annular step 2a at its bottom with D2 = 32 mm; 3 - a clamped beam with dimensions lxbxh = 16x7x4 mm 3 and power input unit 3a; 4 - MMT measuring 3x3 mm 2 from silicon p +type; 4a - transition board; 5 - subminiature connector type PC-4, connected by wires to the board; 6 - six holes ∅ 2 mm for attaching the beams to the object: two - for a movable and four - for a fixed; 7,8 - limiters of movement of the nuts "up" and "down"; 9 - mini-cable ∅ 2 mm; 10 - groove with a cross-sectional size of 1xh2 = 3x2 mm 2 ; O - O' axis of rotation of the movable beam and nut; φ - angle of rotation of the movable beam; d1=18 mm, d2=22 mm - step diameters.

[0012] The operation of the D is as follows: the movable and fixed beams are attached to the object being measured, and a DC voltage of 5...7 V is applied to the MMT. As the angle φ changes, the beam and MMT are deformed, resulting in an electrical signal proportional to the measured angle φ being generated at the bridge output. The range of measured angles is determined by the location of the "zero" setting: in the middle or at the beginning of the measurement range, and can be ±165° or ±330°, respectively. The advantages of the proposed D include the ability to manufacture reliable, simple-design, and inexpensive DMTs capable of operating in harsh operating conditions.

[0013] Sources of information used by the author:

[0014] 1. Elements of instrumentation devices, part 2, edited by O.F. Tishchenko, M., Higher School, 1982.

[0015] 2. Patent RU No. 2860158; BI No. 1 dated April 14, 2026

Claims

1. An angle sensor (D) comprising a screw with a fixed beam and a nut with a movable beam, a fixed beam (B) with a monolithic bridge of semiconductor strain gauges (MMT), with a force-inputting unit (FU), characterized in that the fixed beam is made integral with the screw in the form of a cup, inside which the beam (B) is attached to the bottom, and the force-inputting unit (FU) rests on an annular step made on the bottom of the nut, wherein when the nut moves along the thread of the screw, the force-inputting unit (FU) moves synchronously with it, which leads to deformation of the beam (B) with a monolithic bridge of semiconductor strain gauges (MMT).

2. An angle sensor according to paragraph 1, characterized in that a monolithic bridge of semiconductor strain gauges (MMT) is fixed on the back side of the beam (B) at its termination, the leads from it are soldered to the contacts of the transition board fixed next to the MMT, on the other side, the leads of the PECF-0.1 wire are soldered to the board, passing through the hole in the bottom of the screw and then designed in the form of a microcable laid in a groove of depth h2, width b1, connecting this hole with the hole for the connector, which is fixed on the fixed beam from the front side, the ends of the wires of the microcable are connected to it by soldering.

3. An angle sensor according to paragraph 1, characterized in that in a nut with an outer diameter D1, on its bottom with a diameter D2, an annular step of height h1 is formed in one piece between diameters d1 and d2, which, when the nut rotates, moves vertically and at the same time presses on the force-input unit (FIU), which causes deformation of the beam (B) with a monolithic bridge of semiconductor strain gauges (MMT).

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