RU2791344C1 - Composite crankshaft (options) - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: group of inventions relates to the field of mechanical engineering, in particular to composite crankshafts. The composite crankshaft according to the first version contains a drive link, a connecting crank and a main journal of the last link of the crankshaft. The drive link of the crankshaft is made in a single piece in the form of a knee. The knee consists of a main journal, a crank and a crankpin. The crankpin is connected by means of clamps, a key and fasteners holding the fasteners of the crankshaft links to be fixed. The main journal of the last link of the crankshaft is made as a single part in the form of a half-knee, consisting of a pin with a crank. The knee and the half-knee are provided with protrusions and grooves for connection to each other. Composite crankshaft according to the second version contains the main journal of the last link of the crankshaft, which is the output shaft. The crankshaft is made of identical composite links, which are a single part made in the form of a half-knee. A half-knee comprises a main journal with a crank. Each half-knee and the output shaft are provided with protrusions and grooves for connection to each other.

EFFECT: reduction in the mass of the shaft is achieved.

2 cl, 6 dwg

Description

The invention relates to mechanical engineering, namely to composite crankshafts, mainly for drilling pumps and internal combustion engines.

The proposed technical solution can be used in mechanisms that convert rotational motion into reciprocating.

From the prior art, a composite crankshaft is known (RF patent
No. 2095647, IPC F16C 3/12), containing cheeks, at least one connecting rod and main journals connected to the cheeks, and a device for fixing the necks from rotation relative to the cheeks. Moreover, the necks are connected to the cheeks by means of fingers pressed into the end holes of the cheeks, or by means of a flange connection, and the fixing device is made in the form of at least one cylindrical protrusion located on the end surface of the neck eccentrically to its longitudinal axis and installed freely in the landing hole of the cheek.

The disadvantages of the specified composite crankshaft are its increased axial dimensions and weight, as well as insufficient rigidity and durability of the shaft.

Known composite crankshaft (RF patent No. 2588322,
IPC F16C 3/12), selected as a prototype, containing cheeks and at least one connecting rod and two main journals, each cheek is made in the form of a connecting rod and main caps fastened to two racks, and has a through mounting hole in which the connected between themselves, the connecting rod and main journals, as well as four half rings, fixing the necks from axial movement, while the connecting rod and main journals are combined with the corresponding connecting rod and main journals by means of keys, which simultaneously perform the function of transmitting torque to the shaft and the function of fixing the necks from turning relative to the cheeks , and the necks are additionally provided with protrusions and grooves for connecting them to each other to form a crankshaft.

The disadvantages of this composite crankshaft are a complex design with a large range of original parts, due to this - low maintainability, as well as insufficient rigidity and durability of the shaft.

The technical result of the claimed invention is to reduce the weight of the shaft, improve manufacturability, maintainability and durability by reducing the number of parts included in its composition and increasing its rigidity.

The technical result is achieved by the design features of the composite crankshaft, the drive link of which is made as a single part in the form of a knee, consisting of a root pin, a crank and a connecting rod. The drive link is connected by means of clamps with spacers installed between them, a key installed in a through bore, and fasteners holding the fasteners of the crankshaft links to be fixed, installed mutually perpendicular both relative to each other and relative to the axis of the shaft, with the root pin of the last link of the crankshaft , which is made as a single part in the form of a half-knee, consisting of a finger with a crank. In this case, the knee and half-knee are additionally provided with protrusions and grooves for connecting them to each other to form a crankshaft.

For the manufacture of the claimed crankshaft and its installation does not require high-precision equipment, and for its maintenance and repair does not require highly qualified personnel.

The claimed technical solution is illustrated by the following description and drawings, which show:

Fig.1 - Three-link composite crankshaft, built of knees;

Fig.2 - Section A-A;

Fig.3 - Section B-B;

Fig.4 - Section B-B;

Fig.5 - Three-link composite crankshaft, built from semi-knees;

Fig.6 - Section G-G.

There are two versions of the composite crankshaft.

In the first embodiment, the composite crankshaft
(see Fig. 1) may consist of at least three elbows 1 and one half-elbow 2, connected by means of two cranks (Fig. 3), each consisting of two clamps 3 and two spacers 4, tightening fitting bolt 5, two prismatic keys 6, as well as fasteners 7. Bearings 8 are installed on the fingers of the crankshaft links.

In the second embodiment, the composite crankshaft
(see Fig. 5) may consist of at least two semi-elbows 2 and one output shaft 9.

The drive link of the crankshaft is a knee 1 containing a root pin, a connecting rod pin and a crank, made of the same material and representing a single piece. This design allows to reduce the number of independent original parts used in the crankshaft in comparison with the prototype.

The half-knee 2 or the crankshaft main link pin is a cylindrical pin made together with the crank, which includes the clamp 3. With the help of the clamp 3, the connecting rod pin of the crankshaft link - the knee 1 is fixed. The advantage of this proposal is the absence of an extra connection, which allows increase the rigidity of the crankshaft.

The connecting crank of the crankshaft (see Fig. 3) differs from the prototype in the absence of four semicircular keys, and for uniform fixing, one fixing bolt is used - a tightening fitting bolt 5, which is also a cylindrical key that holds the fixed fingers of the crankshaft links in alignment. So, in the proposed design of the crank, the fastening of the fingers of the crankshaft links (Fig. 1) is carried out in two opposite directions with the help of fasteners 7, which increases the degree of fastening of the fingers and increases the rigidity of the crankshaft.

The proposed solution differs from the prototype in the absence of forces that distort the threaded holes in the racks.
(see Fig. 2 to patent No. RU 2588322 C1), and fewer original parts.

For example, a single-link crankshaft consists of one elbow 1, one half-elbow 2, one clamp 3, a fixing fastener - a fitting bolt 5 (standard products are not indicated).

The crank of the above crankshaft, in contrast to the prototype, does not have four semi-rings (see Fig.2 to patent No. RU 2588322C1), which act as annular keys, and the proposed fitting bolt 5 eliminates the misalignment of the axes of the fasteners of the clamps 3 and at the same time is a cylindrical key that prevents axial movements of the connected links of the crankshaft.

A set of parts for building a composite crankshaft is recruited depending on the number of connecting rod pins.

When assembling a single-link crankshaft, the drive root of the link (knee 1) must be placed on the same axis as the root pin of the half-elbow 2. In this case, it is necessary to align the keyways with the key 6 in the clamp 3 and the connecting rod pin of the link (knee 1) and fix it with a fitting bolt 5 and fasteners 7. Assembly can be performed with bearings 8 already installed on the fingers both in the technological device and at the place of installation of the mechanism.

When assembling a multi-link crankshaft (see Fig. 1), for example, a three-link one, it is necessary to set the main pins of the drive links (elbows 1) in the amount of three pieces coaxially with the main pin of the last link (half-elbow 2), while aligning the splines on the main pins. Connect the connecting rod pins of the drive links and the root pins of the next drive link using a connecting crank (see Fig. 3), putting the connecting rod and main pins into the corresponding holes in the cranks, and, tightening the fasteners on the clamps 3, fix with a fitting bolt 5.

As a second option (see Fig. 5), it is proposed to perform a composite crankshaft, consisting of semi-elbows 2 connected to each other in series without using spacers 4 between clamps 3. Each subsequent semi-elbow 2 is connected to the previous semi-elbow 2 using a key 6 and a clamp 3. Thus, the number of parts is significantly reduced (both spacers 4 and two clamps 3, as well as half of the fasteners for fastening the clamps 3 are excluded), which ensures greater structural rigidity and assembly accuracy.

Claims (2)

1. A composite crankshaft containing a drive link, a connecting crank, and a root pin of the last link of the crankshaft, characterized in that the drive link of the crankshaft is made as a single piece in the form of a knee, consisting of a main pin, a crank and a connecting rod connected by means of clamps with spacers installed between them, a key installed in a through bore, and fasteners holding fastened fingers of the crankshaft links, installed mutually perpendicular both relative to each other and relative to the axis of the shaft, with the root pin of the last link of the crankshaft, which is made as a single piece in in the form of a half-knee, consisting of a finger with a crank, and the knee and half-knee are additionally provided with protrusions and grooves for connecting them together to form a crankshaft. 2. A composite crankshaft containing a drive link, a connecting crank and a root pin of the last link of the crankshaft, which is the output shaft, characterized in that the crankshaft is made of identical composite links, which are a single part in the form of a half-elbow, consisting of a root pin with a crank , connected by a clamp, a key installed in a through bore, and fasteners holding fastened fingers of the crankshaft links, installed mutually perpendicular both relative to each other and relative to the axis of the shaft, with the output shaft, each half-elbow and the output shaft are additionally provided with protrusions and grooves for connecting them together to form a crankshaft.

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