RU2509221C1 - Device for fan start-up - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: device comprises a sensitive element made from ferromagnetic material with Curie point equal to critical temperature of cooling liquid placed into a body from non-magnetic material and a permanent cylindrical magnet placed in it with the possibility of free movement inside the cavity, besides, the ends of the sensitive element and the permanent cylindrical magnet are connected with a spring, and the second end of the permanent cylindrical magnet rests against the body of the switch with magnetically controlled contacts, and the second end of the sensitive element has contact with the cooled medium.

EFFECT: higher reliability of device operation and simplified design of fan drive.

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Description

The invention relates to the field of engineering and can be used to turn on and off the fan of the cooling system of internal combustion engines.

A device [1] for turning on a fan is known, which is equipped with a hydraulic coupling transmitting rotation due to the adhesion of a highly viscous fluid. The working and backup cavities of the hydraulic coupling are separated by a partition mounted rotatably around a central axis. Depending on the ambient temperature, a bimetallic spiral acts on the specified partition, which stops the viscous fluid from entering the working cavity of the coupling, ensuring its shutdown.

The disadvantage of this device is the low reliability of the coupling due to the possible leakage of the working fluid, and the temperature sensitive element is affected by the ambient temperature and the fan turns on or off prematurely.

Known hydraulic fan drive [2] with automatic maintenance of the optimum temperature of the engine, containing a fluid coupling and a regulator-switch mode of operation. The fan drive fluid coupling provides torque transmission from the crankshaft to the fan. It allows automatic control of the fan speed by changing the flow rate of oil passing through the working cavity of the coupling due to the regulator-switch, and therefore its performance. Depending on the temperature of the liquid in the engine cooling system, the change in the amount of oil in the fluid coupling body is regulated, respectively, the fan is turned on and off.

The disadvantages of this fan drive are the design complexity, low reliability of the regulator-switch due to the frequent activation of the spool in the regulator, wear of the rubber seal collar and oil leakage in the fluid coupling housing.

A device [3] for turning on a fan is known, which is equipped with a sensor made of a shape memory material having the form of a stepped bellows, a spring is located between the driven and drive disks, and the ends of the pulleys associated with the hubs are opposite to each other and made in the form of a helical gearing.

The disadvantages of this device are the design complexity, the appearance of wear of the ball bearings and the teeth of the driving and driven pulleys and the rather slow gear engagement due to the fact that the sensor is made of material with a shape memory in the form of a stepped bellows.

The present invention solves the problem of creating a device for automatically turning on the fan and maintaining the optimum temperature of the engine cooling with high reliability and simplified design.

The technical result is to increase the reliability and simplify the design of the device.

The specified technical result is achieved in that the device for turning on the fan contains a sensor and a spring.

A feature of the device is that it is equipped with a sensitive element made of a ferromagnetic material with a Curie point, placed in a housing made of a non-magnetic metal alloy with a permanent cylindrical magnet placed in it with the possibility of free movement inside the cavity of the body, the ends of the sensitive element and a permanent cylindrical magnet with a spring, and the second end of the permanent cylindrical magnet abuts against the switch housing with magnetically controlled contacts, and the second ec sensing element is in contact with a cooled medium.

The essence of the invention is illustrated by drawings, where Fig. 1 shows a schematic diagram of a device for turning on a fan, and Fig. 2 shows a diagram of a fastening device for turning on a fan of an engine cooling system.

The device contains a sensing element 1 (Fig. 1) made of ferromagnetic material with a Curie point equal to the critical temperature of the liquid in the radiator 2 for turning on the fan, and rigidly fixed inside the upper tank 3 of the radiator 2 (Fig. 2) so that it is free the end had contact with the cooled medium; the sensing element 1 is placed in a housing 4 made of a non-magnetic metal alloy, inside which a cylindrical permanent magnet 5 is placed with the possibility of free movement inside the cavity of the housing 4, and the ends of the cylindrical permanent magnet 5 and the sensing element 1 are connected by a spring 6; the second end of the cylindrical permanent magnet 5 abuts against the housing 4 with a switch 7 with magnetically controlled normally open contacts and is rigidly attached to the housing 4.

The device operates as follows. In the initial state, when the coolant temperature t ° inside the upper barrel 3 of the radiator 2 is below critical, the sensitive element 1 having ferromagnetic properties attracts a cylindrical permanent magnet 5, compressing the spring 6. In this position, the cylindrical permanent magnet 5 does not affect its magnetic field to the normally open contacts of the switch 7 and the electromagnetic clutch of the fan is switched off. The force of magnetic attraction of the sensing element 1 and magnet 5 exceeds the compression force of the spring 6.

When the temperature of the coolant reaches more than 80 ° C, the sensitive element 1 is heated in the tank 3 of the radiator 2 and due to the transition of the Curie point loses ferromagnetic properties, the attractive force of the permanent cylindrical magnet 5 disappears and the spring 6 located between them pushes the cylindrical permanent magnet 5 , which by its magnetic field acts on the switch 7, and the contacts are closed in the power circuit of the electromagnetic clutch of the fan drive, including the fan for cooling.

The use of a device in the engine cooling system, the sensitive element of which is made of ferromagnetic material with a Curie point equal to the critical temperature of the coolant, will significantly simplify the design and increase its reliability.

LITERATURE

1. Application No. 59-27453, IPC F16B 35/00, Japan, publ. 05.-7.1984.

2. Medvedev V.I., Bilyk S.T., Grishin G.A. Cars KamAZ-5320, KamAZ 4310, Ural-4320. M .: DOSAF, USSR, 1987.

3. Patent No. 2432471, IPC F16B 35/00, 2011.

Claims (1)

A device for turning on a fan, comprising a temperature sensor and a spring, characterized in that it is provided with a sensing element made of a ferromagnetic material with a Curie point equal to the critical temperature of the coolant, placed in a non-magnetic metal alloy housing with a permanent cylindrical magnet placed in it with the possibility free movement inside the cavity of the housing, with the ends of the sensing element and a permanent cylindrical magnet connected to the spring, the second end along a stationary cylindrical magnet abuts against the switch housing with magnetically controlled contacts, and the second end of the sensing element has contact with the cooled medium.

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