RU2214585C1 - Gear wheel test stand - Google Patents

Abstract

FIELD: mechanical engineering; testing facilities. SUBSTANCE: invention relates to stands for testing of machine parts and studying of materials by determining their chemical or physical properties, namely testing of oils. Proposed stand contains two coaxially installed central gear wheels, and carrier with gang of planet pinions. One central gear wheel is rigidly secured on post. Other central gear wheel is installed on post for rotation. Gang of planet pinions contains two gear wheels rigidly secured on shaft and it is installed for rotation of carrier installed for rotation of post coaxially with central gear wheels. Load lever is rigidly connected to movable central gear wheel. Said lever can be loaded electromagnetically, hydraulically, muscularly and also by elastic or gravity forces. Invention provides control, changing measuring of torque, changing direction of action and "sign" of torque action, both when stand is stopped and is in operation at working speeds of shafts. EFFECT: enlarged operating capabilities. 1 dwg

Description

 The invention relates to tests of various designs, namely to stands for testing machine parts, as well as to research materials by determining their chemical or physical properties, namely the testing of oils.

 A well-known bench for testing gears, containing a closed loop formed by two parallel shafts that are mounted to rotate on racks. At the ends of each shaft, identical gears are fixed in pairs. They are equal in terms of the number of teeth and in modulus. One of the shafts has a coupling, which allows you to twist the shafts, loading the gears with torque [1].

 The disadvantage of this stand is the difficulty of obtaining a given torque, as well as the low reliability of its fixation due to self-loosening when tightening the coupling. However, it is impossible to adjust the amount of torque during the rotation of the shafts. All this leads to a distortion of the experimental results.

 There is also a stand for calibrating dynamometer shafts, containing pairwise interacting with each other two pairs of gears, which are rigidly fixed at the ends of two shafts, and the gears are the same. One pair of gears is fixed in the housing, which is rotatably mounted on a rack with a certain angle relative to the horizontal plane, and one of the shafts contains a front and a ball joint with a finger, which allows turning the case of a pair of gears relative to the rack [2].

 The main disadvantage of this stand is the complexity of the design and processes for obtaining, measuring and changing the required torque. It is necessary to additionally measure the reactions of the supports and the moment bending the shaft. Unable to create alternating moment.

 Closest to the invention in design is a planetary gear reducer. It contains two coaxially mounted, central gears, one of which is rigidly mounted on the rack, and the other is mounted rotatably on the rack. A satellite block interacts with them, which contains two other gears rigidly mounted on a shaft mounted for rotation on the carrier, and the carrier is mounted for rotation on a rack coaxially with the central gears [3].

 The purpose of the invention is the regulation, change, measurement of the magnitude of the torque, changing the direction of action and changing the "sign" of the action of torque both on a stopped and on a working stand at working speed of rotation of the shafts.

This goal is achieved in that the central gears are equal to each other in terms of the number of teeth z ₁ = z ₂ and modulo m ₁ = m ₂ , as well as the satellites are equal in modulus and in number of teeth, i.e. there is no transmission of movement from the input link to the output, provided that the input link is a carrier.

 The drawing shows a schematic diagram of a bench for testing gears.

 The stand contains two coaxially mounted, central gears. The Central gear 1 is rigidly mounted on the rack, and the Central gear 2 is mounted to rotate on the rack. The satellite block 3 interacts with them, which contains two other gear wheels rigidly fixed to the shaft. The satellite block 3 is mounted rotatably on the carrier 4. The carrier 4 is mounted rotatably on the rack, coaxially with the central gears 1 and 2. The load lever 5 is rigidly fixed to the central gear 2. The method of loading the lever does not matter. This can be electromagnetic, hydraulic, muscle loading, as well as loading by elastic forces or gravitational forces.

Stand for testing gears works as follows. The carrier 4 is supplied with a torque T _n , telling him the movement with a rotation frequency ω _n . Accordingly, the movement is transmitted to the satellite block 3, which begins to rotate around a stationary central gear wheel 1 with a rotation frequency of ω _n , and around its own axis with a frequency of ω _s .

Since the central gears 1 and 2 are the same (m ₁ = m ₂ , z ₁ = z ₂ ), the rotational speed of the movable central gear 2 will be equal to the rotational speed of the stationary central gear 1, i.e. wheels will not spin. Thus, carrier 4 will rotate idle, i.e. without transmitting movement to the central movable gear 2.

Now, if you apply a torque T ₅ to the load lever 5, then the movable central gear 2 will rotate within a certain angle and the moment M will appear on the shaft of the satellite block 3.

The force on the load lever can be created both when the stand is stopped and when it is working. In the stand of this design, it is possible to change both the magnitude of the torque T ₅ and its direction, as well as the moment T ₅ can be alternating.

You can control the torque T _{5 by} adding a dynamometer to the load lever 5.

Thus, it can be seen from the diagram that the power from the torque T _{n is} spent only on overcoming the forces of resistance to movement (in particular, friction forces) and on communicating the movement to the links of the stand and is not spent on creating torque M on the shaft of the satellite block 3, and
M • ω _s > T _n • ω _n ,
where M • ω _s - power in a closed loop (closed power), W;
T _n • ω _n - power on carrier 4, W,
respectively, M> T _n [3].

The stand can also be used for calibration of dynamometer shafts. In this case, the dynamometer shaft will be the shaft of the satellite unit 3, and only the torque T ₅ will be sufficient to measure.
LITERATURE
1. Reshchikov V.F. Friction and wear of heavily loaded gears. - M.: Mechanical Engineering, 1975 .-- 232 p.

 2. A.S. 412497, manual gearbox G 01 L 1/04, METHOD FOR DYNOMETRIC SHAFT TARGING.

 3. Krainev A.F. Dictionary reference to mechanisms. - 2nd ed., Revised. and add. - M.: Mechanical Engineering, 1987 .-- 560 p.

Claims (1)

 A gear test bench, comprising two coaxially mounted central gears, one of which is rigidly mounted on a strut, and the other is rotatably mounted on a strut, and a satellite gear pair interacting with them, which contains two other gears, rigidly mounted on a shaft mounted rotatably on a carrier mounted rotatably on a strut coaxially with central gears, characterized in that the central gears are equal to each other in and the number of teeth, and on the central gear mounted rotatably on the rack, the load lever is rigidly fixed, and the gears of the satellite block are equal in absolute value and in the number of teeth, and the gearing of the satellites with the central gears must either only external, or only internal.