RU2595993C1 - Device for varying crank radius of crank mechanism - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates to machine building, particularly to piston machines. Crank mechanism, containing crankshaft consisting of crankshaft necks and crank pins, connected by crankshaft webs, characterized by the fact that crankshaft webs have guide slots, where steady bushes of the crank pins are installed, rings are placed near the crankshaft webs on crank pins, rings are in contact with additional rings, two rings are installed inside the main ring, which is located inside the guide ring, the auxiliary ring is installed between the main and guide rings, guide ring is arranged in the housing guide slots and rests on the assembly of said ring movement and fixation. Crank radius varying from zero to maximum value enables reaching full operation mode of pistons machines with low starting torque.

EFFECT: disconnecting some pistons from the crankshaft, at simultaneous disconnecting the fuel supply, enables using the piston machine with power save mode under various operating conditions; easier engine starting conditions in winter period.

1 cl, 4 dwg

Description

The proposed device relates to mechanical engineering, in particular to piston machines: ICE (internal combustion engines), compressors, pumps, including multi-cylinder; and also SK (rocking machines) using KShM (crank mechanism).

A device is known - ICE, the basis of which is a KShM, which converts the reciprocating motion of the piston into rotational motion of the crankshaft (1. Internal combustion engines: Design and operation of reciprocating and combined engines. / VP Alekseev and others; Under the general. Edited by A.S. Orlin, M.G. Kruglov. - M.: Mechanical Engineering, 1990. - 288 p.).

KShM is used as the basis for some SKs (2. Patent for invention RU No. 2450161. Bull. No. 13 of 05/10/2012. Authors: V.I. Nekrasov, VV Novoselov - Appendix). Currently, R&D (development work) of this invention is being carried out.

It is known that the crankshaft consists of cranks formed by the main and connecting rod necks of the crankshaft connected by the cheeks, as well as connecting rods mounted on the connecting rod necks. Pistons are located on the connecting rods, and in some cases (for example, mud pumps) crossheads (sliders in the guides) are used, which exclude the transfer of high lateral loads to the pistons and cylinders.

However, the KShM has significant drawbacks: lateral loads, which reduce the efficiency of the piston machine, a fixed piston stroke, which limits operational capabilities.

The problem to which the claimed technical solution is directed is to expand the capabilities of the piston machine and SK.

The essence of the proposed device lies in the fact that the crank mechanism comprises a crankshaft consisting of main and connecting rod necks connected by crank cheeks, while the crank cheeks have guide grooves in which supporting bushings of the connecting rod necks are installed, crank cranks are located on the connecting rod necks rings in contact with additional rings, two rings are installed inside the main ring, which is located inside the guide ring, between the main and guide rings installed mogatelnoe ring, guide ring device disposed in the guide grooves and the housing rests on movable assembly and fixing of the ring.

The proposed technical solution significantly expands the capabilities of the piston machine. Changing the radius of the crank from zero to the maximum value allows the SC to enter the operating mode with a low starting torque. Disconnecting a part of the pistons from the crankshaft, while shutting off the fuel supply to the cylinders of these pistons, allows the piston machine to be operated in an economical mode under various operating conditions; easier conditions for starting the engine in winter.

In FIG. 1 shows a simplified cross section of a piston machine in a state when the piston is in its highest position: at TDC (top dead center), the piston is at the maximum distance from the axis of the crankshaft. BDC (bottom dead center) - the piston at a minimum distance from the axis of the crankshaft. Piston rings, bearings for rotation of the crankshaft journals, etc. are not shown. Designations: OK - axis of rotation of the crankshaft (the axis of the main journals), Osh - axis of the crank pin, OOS - axis of the main ring, He - axis of the guide ring, Od - axis of the additional ring , Ov is the axis of the auxiliary ring. The dashed line indicates the movement of the connecting rod journal when the crankshaft rotates. Numbers 1-4 show the position of the connecting rod journal in extreme states.

In FIG. 2 shows a simplified longitudinal section of a piston machine. Three cranks with different radii are shown: on the left, R = 0, the axes of the main and connecting rod necks coincide; in the center R = 0.5 R _max ; R = R _max on the right, corresponds to FIG. 1. Cheeks of cranks are turned on 180 °, average - down; extreme up.

In FIG. 3 shows the arrangement of the rings of the device for changing the radius of the crank at R = 0.5 R _max , which corresponds to the average crank of FIG. 2.

In FIG. 4 shows the arrangement of the rings of the device for changing the radius of the crank at R = 0, which corresponds to the left crank of FIG. 2.

In the housing 1 of the piston machine (Figs. 1 and 2), wet cylinder liners 2 are fixed (seals not shown). It is possible to use a monoblock - the sleeves are made together with the housing 1. Inside the cylinders 2, pistons 3 are installed, which piston fingers 4 connect the pistons 3 with the upper heads of the connecting rods 5. The lower heads of the connecting rods 5 with the connecting rod covers 6 are movably located on the connecting rod necks 7. At the ends of the connecting rod necks 7, support sleeves are made 8. The connecting rods 9 are installed from the ends of the lower head of the connecting rod 5, they can be made similarly to the support sleeves 8 directly on the connecting rod neck 7. The main journals 10 are movably mounted in the rotation supports I, formed by the housing 1 and covers 11. Inserts - bearings of rotation of the main 10 and 7 connecting rod journals are not shown. The crank cheek 12 is fixed on the main neck 10, guide grooves 13 are made in the cheeks 12, in which the support sleeves 8 of the connecting rod journals 7 are located. The connecting rod ring 9 is in contact with the additional ring 14, both rings are located inside the main ring 15. The main ring 15 is located inside the guide rings 16, between the main 15 and the guide rings 16 installed auxiliary ring 17. Guide rings 16 with the rings 9, 14, 15, 17 placed in them are installed in the guide grooves 18 of the housing 1. The direction of the grooves 18 can be any in relative axis of the crankshaft. The guide ring 16 is supported by a displacement and fixing assembly 19.

The proposed device for changing the radius of the crank of the crank mechanism works as follows.

To bring the SC to operating mode, a high starting torque is required - the load for the operation of the SHGN (sucker rod pump) can reach several tons. In addition to the mass of the rod string, the hydraulic load has a significant effect. The torque required for this depends on the product of the fluid pressure and the pump displacement. The displacement of the pump depends on the radius of the crank. At R = 0, the hydraulic load is excluded. At R = R _max this load will be maximum.

To bring the SC to the operating mode, it is advisable to use the state R = 0 (Fig. 2 on the left and Fig. 4). The movement and fixing unit 19 fixes the rings of the device for changing the radius of the crank of the crank mechanism at the maximum distance from the axis of the crankshaft. The axis of the root neck of Oak coincides with the axis of the connecting rod neck of Osh. Idling is ensured - the force is not transmitted to the rod string of the SHGN drive. This state of the crankshaft can be used to turn off the engine cylinders from work.

For a step-by-step gradual withdrawal of SC to the operating mode, the displacement and fixing unit 19 shifts the ring system and fixes them in an intermediate position R = 0.5 R _max (Fig. 2 in the center and Fig. 3). The axis of the root neck of the Oak coincides with the axis of the main Oos ring. The axis of the connecting rod neck Osh is located above the axis of the radical neck Ok and is indicated by the number 1. The dotted line indicates the path of movement of the connecting rod neck when the crankshaft rotates. Numbers 1-4 show the position of the connecting rod journal in extreme states. The connecting rod 9 and the additional 14 rings rotate inside the main ring 15. The torque, for example, from the left main neck 10 by the cheek of the crank 12, by the guide groove 13 at a radius of R = 0.5 R _max transfers force to the supporting sleeve 8 of the left end of the connecting rod neck 7, further along the connecting rod neck to the other, the right end of the connecting rod neck, along the guide groove of the adjacent cheek of the right root neck.

The maximum load occurs at R = R _max , for this, the displacement and fixing unit 19 shifts the ring system and fixes them in the extreme upper position R = R _max (Fig. 1 and Fig. 2 to the right). The axis of the root of the neck Ok coincides with the axis of the guide ring He. The axis of the connecting rod neck Osh is located at the maximum distance from the axis of the radical neck Ok and is indicated by the number 1. The dotted line indicates the path of movement of the connecting rod neck when the crankshaft rotates. Numbers 1-4 show the position of the connecting rod journal in extreme states. The connecting rod 9 and the additional ring 14 together with the main ring 15 and the auxiliary ring 17 rotate inside the guide ring 16. The increased torque is transmitted similarly to the previous case, while the support bushings 8 of the connecting rod journal 7 have a large contact area with the guide grooves 13 of the crank 12 of the crank 12.

Designations:

1 - the body of the piston machine;

2 - wet cylinder liner;

3 - the piston;

4 - a piston finger;

5 - a rod;

6 - a cover of the lower head of a rod 5;

7 - a connecting rod neck;

8 - supporting bushings of the connecting rod journal 7;

9 - connecting rod rings;

10 - a radical neck;

11 - cover of the support of rotation of the root neck 10;

12 - crank cheek;

13 - guide groove of the cheek crank 12;

14 - an additional ring;

15 - the main ring;

16 - a directing ring;

17 - auxiliary ring

18 - guide grooves of the housing 1;

19 - node moving and fixing the guide ring 16.

Claims (1)

A crank mechanism containing a crankshaft, consisting of main and connecting rod necks connected by crank cheeks, characterized in that the crank cheeks have guide grooves in which support bushings of the crank journals are installed, rings contacting additional cranks are located on the crank cheeks rings, two rings are installed inside the main ring, which is located inside the guide ring, between the main and guide rings there is an auxiliary ring, a guide ring stroystva arranged in the guide grooves and the housing rests on movable assembly and fixing of the ring.

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