RU2052637C1 - Driving gear for distributing shaft of internal combustion engine - Google Patents

Abstract

FIELD: engine engineering. SUBSTANCE: gear has hub and toothing. Two circular torus-like passageways are made concentrically with respect to the axis of rotation between the shaft and toothing. Steel springs are received in the passageways. Two side rings close the faces of the gear from left and right sides. The side rings has shaped chamferings. The ring ports are interposed between the chamferings. Locating members for springs are received in the torus- like passageways. The locating members are secured to the side rings. EFFECT: improved design. 3 dwg

Description

 The invention relates to gas distribution mechanisms of internal combustion engines, in particular piston engines of automobiles, and can be used in mechanical engineering and in the operation of a country's fleet.

 It is known that modern gas distribution systems of mass-produced piston engines have a significant drawback, namely: when the engine speed changes, the gas distribution phases remain unchanged.

 While engine operating conditions continuously change with an increase (decrease) in the number of its revolutions, car plants are forced to select the optimal valve timing for average engine revolutions. This negatively affects the operation of the latter at idle, during a set of revolutions and in braking mode. The duration of opening the valves in each particular machine will have some specific value. This phenomenon is associated with the features of the inlet and outlet channels, the shape and diameter of the valves, the shape and volume of the combustion chamber, and other factors.

 There are many technical solutions at the level of inventions that relate to changes in valve timing in an internal combustion engine depending on the speed.

Only Mercedes systems found practical application in industry, in which the gas distribution phases are changed by electric motors controlled by electronic devices, which brings 12-15% fuel economy. The system of the company Mercedes allows you to adjust the valve timing by changing the angle of rotation of the engine camshaft. This is also described in the book of K.Sh. Gigauri, D.N. Javashvili. Timing and exhaust gas toxicity of gasoline engines. Tbilisi: Metznasreba. 1985. The authors indicate that at idle engine speed, phase changes ahead of 20 ^° can reduce the emission of harmful exhaust gases by 40% or more and reduce fuel consumption by 20%.

In another book (see A.I. Kolchin, V. P. Dementyev. Calculation of automobile and tractor engines. M. Higher School, 1980, p. 47), it is concluded that the angle of rotation of the camshaft of the gas distribution mechanism, taking into account the timing and delay should be 40-60 ^about . For each specific engine, this value will be different.

 If the opening and closing of the valves is delayed at speeds above average, the inertia of the mixtures or air will be used, which is very effective not only in terms of economy, reduction of exhaust toxicity, but also in terms of increasing power and torque. The latter will increase not only the characteristic of this engine, but also the characteristic of the drive of the engine, automobile, tractor.

 The arrangement and operation of the gas distribution mechanism is also described in the book by V.I. Anokhin. Domestic cars. M: Mechanical Engineering, 1964, p. 69-78. Thus, the relevance of the task is obvious. The UK patent N 1095017, class. F 01 L 1/34 publ. 1967. The patent describes a camshaft gear of a gas distribution mechanism of an internal combustion engine. In the gear, the crown can be rotated relative to the hub by a limited angle of rotation due to spiral and leaf springs and clamps of various kinds of springs and crowns relative to the hub.

 The disadvantages of the prototype are the small angle of rotation of the crown relative to the hub, an increase in the size of the gear compared to the standard gear, the difficulty of placing the mechanism on the gear, the difficulty of transmitting a fairly significant torque using these mechanisms.

 The above disadvantages make the patent of practical value.

 For the purpose of practical application, the proposed camshaft drive gear of an internal combustion engine is made with toroidal channels located inside the crown and outside the hub, the channels are guides for coil springs, spiral springs, in turn, are guides for the crown and hub.

 A design of the drive gear of the camshaft drive is proposed, characterized in that toroidal channels are made inside the crown and outside the hub, which are guides for coil springs, the latter, in turn, serve as guides for the crown and hub.

The essence of the invention is that due to the limited angular rotation of the crown relative to the hub, to achieve a change in the gas distribution phases depending on the increase (decrease) in the number of engine revolutions, which reduces the exhaust gas emission and leads to significant fuel economy of at least 10%
In FIG. 1 shows a gear, side view; in FIG. 2, 3 shows sections aa and bb in FIG. 1 respectively.

 The gear drive of the internal combustion engine of a car consists of a hub 1 and a crown 2, which are made mutually movable. The hub 1 is mounted on a camshaft (not shown) in a known manner. In the hub and crown housings, channels 3 and 4 of a toroidal profile are made, in which steel coil springs 5 and 6 are installed. Channels 3 and 4 are parallel to each other and equally spaced from the shaft axis.

 The gear also has side rings 7 and 8 mounted respectively on the hub and crown, on their side surfaces by means of fastening elements 9. The side rings 7 and 8 have profile bevels 10, and between them there are annular windows 11.

 In the toroidal channels 3 and 4, spring clamps 12 and 13 are installed. For the convenience of manufacturing, they are fixed on the side rings 7 and 8, but they can also be installed in the crown and hub housings.

The springs 12 and 13 are set symmetrical with respect to the camshaft sections covering canals circumference 120 ^of CL so that between them can be areas without springs 60 ^about the angle of maximum rotation relative to the hub ring.

In the proposed form, the gear is almost no different from the regular gear of any car. When replacing factory gear alignment mark should shift about ²⁰ ° ahead of the engine.

 The work of the proposed gear is as follows.

 When starting the engine at first, at its first revolutions, the gear does not functionally affect the gas distribution mechanism, since the force required to move the hub relative to the crown is perceived by steel springs 5 and 6. With an increase in the number of revolutions, the force required to rotate the camshaft increases the fact that to overcome the resistance of the valve springs (not shown) by one revolution requires a very definite force. With a further increase in the engine speed, the indicated force increases linearly. If the selected springs 5, 6 change their length linearly, with a change in the pressure force on them, they will be compressed with fairly high accuracy.

 Crown 2 begins to lag in strict accordance with the law of increasing engine speed. The higher the number of revolutions, the greater the angle of delay of the crown 2. At maximum speeds, it will be maximum.

 Since the valves and, accordingly, the valve block springs do not work simultaneously, the change in the angle of rotation of the crown relative to the hub will be smooth and will depend in direct proportion to the number of revolutions. Slight vibration will be suppressed by both the springs 5 and 6, and the valve springs. The essence of the invention is to uniformly increase the torque depending on the increase in the number of revolutions of the engine. This is due to the one-time resistance of the spring complex with increasing speed. The higher the revolutions, the higher the integrated resistance of the springs, the more the valve timing corresponds to the actual engine operation cycle. This is very significant and unusual in the concept of a piston internal combustion engine. The higher the engine speed, the greater the angle of shift of the gear crown relative to the hub, the greater the angle of the valve operation delay.

 Thus, the operation of the proposed device meets the theoretical and practical prerequisites for regulating the gas distribution mechanism during engine operation in order to reduce toxicity and increase engine efficiency.

 With a decrease in the engine speed, the valve lag angle or the shift angle between crown 2 and hub 1 will decrease accordingly.

The proposed device will be especially effective when driving around the city, where the toxicity of exhaust gases will decrease by no less than 20% and the economy will increase by no less than 10%
If springs are made of calibrated steel, and then they are processed using grinding wheels after heat treatment on a circular grinding machine, then, taking into account the small number of springs and their thickness in comparison with the gas distribution mechanism springs, they will simultaneously serve as guides between the crown and gear hub, especially considering that gears have significant tolerances, i.e. almost the springs themselves, the crown and the hub will completely cope with the high accuracy of gearing of the gears of the gas distribution mechanism, or chain or belt transmission. At the same time, it is necessary to manufacture the proposed gear with sufficiently high accuracy.

Claims (1)

 INTERNAL COMBUSTION ENGINE DRIVING SHAFT GEAR, containing a crown and a hub mounted on the shaft with the possibility of limited angular rotation relative to each other using coil springs and clamps, characterized in that toroidal channels are made inside the crown and outside the hub, which are guides for spiral springs the latter, in turn, serve as guides for the crown and hub.

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