RU2181322C2 - Apparatus for finishing and strengthening journals of crank shafts - Google Patents

Abstract

FIELD: machine engineering, possibly repairing operations such as finishing journals of crank shafts after their regrinding for repairing size or after restoring their metallic coating. SUBSTANCE: apparatus includes mandrel with jointly mounted fork-like holder carrying deforming members. Fork-like holder is spring-loaded and it is provided with two heads with deforming members in the form of balls arranged in spherical grooves of inserts and hold in said grooves by means of rests and single-side asymmetrical protrusions of head bodies. Said rests are secured to head bodies which are joined with ends of fork-like holder with possibility of adjustment. There are adjusting grooves in rests and on ends of fork. Axes of articulation joint of one head are shifted relative to axes of articulation joints of other head by value a=(0.1-1)R. Distance between protruding balls of one head and end faces of body of other head is determined according to relation b=(0.1-0.9)R, where R - ball radius. Apparatus allows to significantly enhance quality of worked surfaces due to applying regular microrelief onto them. EFFECT: enhanced operational parameters of crank shaft, improved efficiency of apparatus. 2 cl, 4 dwg

Description

 The invention relates to the field of mechanical engineering and can also be used in repair production during the finishing processing of crankshaft necks after regrinding to a repair size or after restoration with metal coatings.

 A device for processing crankshaft necks by microfinishing is known, consisting of a mandrel, heads in which two abrasive blocks are installed, the abutment bars abutment against the crankshaft neck by a spiral spring located inside the mandrel. To improve the quality of the machined surface, the mandrel, together with the grinding bars, oscillates along the axis of the neck of the rotating crankshaft [1].

 However, the device for finishing the processing of the crankshaft is designed to smooth surface scallops and does not allow hardening of the surface layer of the neck of the crankshaft, applying regular microrelief on it, which improves the operational properties of the shaft.

 Known devices for finishing the outer surfaces of bodies of revolution, in which a ball is used as a finishing element, the support for which is a ball bearing installed in the housing, the ball is kept from falling out of the separator [2].

 During the rotation of the workpiece, the ball is also provided with an ascending motion in addition to the feed, which, along with hardening the part, provides a regular microrelief on its surface that improves the operational properties of the part.

 However, such devices do not allow the processing of the surfaces of the necks of the crankshaft due to the presence of fillets and channels for lubrication, in the opening of which a dropping of the finishing element (ball) is possible.

 A device is known for processing flat surfaces of parts by vibro-rolling, comprising a housing, a drive cage with an eccentric shaft, a separator with deforming elements provided with additional eccentrics, one axis of which is fixed in the cage and the other in the body, while their eccentricity is equal to the shaft eccentricity and coincides with him in the direction of [3].

 The disadvantage of this device is the inability to use it to process bodies of revolution and create a regular microrelief on the surface.

 Closest to the proposed invention in terms of features is a device for the finishing and hardening of the necks of the crankshafts, containing a mandrel with a pivotally mounted and spring-loaded fork-like holder carrying deforming elements [4].

 However, the known device does not provide high performance and does not allow to obtain a surface with regular microrelief, as it has only two deforming rollers installed in one horizontal plane.

 The objective of the invention is to increase the productivity and quality of surface treatment due to the rational placement of balls.

 This object is achieved in that the device for the finishing and hardening of the necks of the crankshafts containing a mandrel with a pivotally mounted and spring-loaded fork-like holder carrying deforming elements, according to the invention it is equipped with two heads with inserts having spherical grooves, stops fixed on the head housings, one of the ends of each of which is made in the form of a protrusion, the deforming elements are made in the form of balls and are located in the spherical grooves of the inserts with the possibility of Erzhanov from falling out by said abutments and protrusions housings, the heads are mounted on the ends of the fork holder adjustably positioned with their housings protrusions asymmetrically to each other, and in the stops and the ends of the fork holder made adjustment slots.

 In addition, the axes of the balls of one head are offset relative to the axes of the balls of the other head by a = (0,1 ... 1) R, and the distance between the extreme protruding balls of one head and the ends of the body of the other head is determined from the relation b = (0,1 ... 0.9) R, where R is the radius of the ball.

 When a is the distance between the axes of two adjacent balls is equal to the radius of the ball R, only then the proposed device provides the highest performance. And the path of the longitudinal supply of the device along the neck of the crankshaft is equal to the minimum value - the radius of the ball R.

 With a decrease or increase in a, the distance between the axes of two adjacent balls from the value of the radius of the ball R by Δ will need to increase by the same value Δ the path of the longitudinal supply of the device for complete surface treatment with balls, which will reduce productivity.

 The distance between the protruding balls of one head and the ends of the body of the other head is determined from the ratio of = (0.1 ... 0.9) R, which allows on the one hand to prevent the ball from falling out of the head body, and on the other to ensure complete processing of the fillet and cheek the neck of the crankshaft without touching the end of the head housing over the surface of the cheek.

 In the case where the distance is ≥ R, the ball may fall out of the head housing.

 In the case where the distance is <0.1R, contact will occur between the cheeks of the neck of the crankshaft and the end of the head housing.

 The inventive geometric parameters of the device allow you to create a regular microrelief on the surface to be treated, thereby improving its quality.

The invention is illustrated by drawings, where:
figure 1 shows a General view of the device with a partial section;
figure 2 - a view of figure 1;
figure 3 is a section along aa in figure 1;
figure 4 is a section along BB in figure 3.

 The device consists of a mandrel 1, on which a fork-shaped holder 2 is pivotally mounted, inside which a spring 3 is installed. At the ends of the holder 2 two head housings 4 with inserts 5 are fixed, balls 6 are laid in the spherical grooves of them. The balls 6 are prevented from falling out by stops 7, and also the protrusions on the head housings 4. The stops 7 are attached to the head housings 4 with bolts 8 with washers 9, and the head housings 4 are attached to the ends of the fork holder 2 with nuts 10 and washers 11. Adjusting grooves are made at the ends of the fork holder 2. The axis of the balls 6 are parallel to the axis of the neck of the crankshaft, and the balls of one head are offset relative to the axes of the balls of the other head by an amount "a", and the ends of the heads are offset from the extreme balls processing the fillets by an amount of "b".

 Self-alignment of the ball heads 4 relative to the neck of the crankshaft is provided by turning the fork-shaped holder 2 on the cylindrical part of the mandrel 1. It is advisable to select the radius of the balls 6 not exceeding the radius of the fillet of the neck of the crankshaft.

 The installation of the heads 4 parallel to the axis of the neck of the crankshaft is carried out using special gaskets 12 installed between the ends of the yoke holder 2 and the head housing 4. To offset the ball heads, adjustment grooves are provided (Fig. 4). To facilitate the manufacture and increase durability in the ball heads provides the installation of inserts 5 with spherical grooves.

 A device for finishing and hardening processing of the necks of the crankshafts works as follows.

 The heads with balls 6 are pressed against the surface of the neck of the crankshaft using a spring 3. When the crankshaft rotates, the heads with balls 6 make a reciprocating motion along the axis of the neck. Moreover, when moving the heads with balls 6 to the left (Fig. 3), the extreme ball of the upper head is pressed against the fillet of the neck of the crankshaft, while moving to the right - the extreme ball of the lower head. This is ensured by the displacement of the balls in adjacent heads relative to the ends of the bodies 4 by a value of "in". Thus, the fillets of the crankshaft neck are run-in with simultaneous roll-in of its cylindrical surface.

 Using the proposed solution in comparison with the prototype can significantly improve the performance of the device and the quality of the processed surfaces by applying regular microrelief to the surface, which improves the operational properties of the crankshaft.

Sources of information
1. V. V. Sasov et al. Technology of automotive engineering. - M.: Mechanical Engineering, 1968, p. 73-74.

 2. Yu. G. Schneider. The formation of regular microreliefs on the details and their operational properties. - L .: Engineering, 1972, p. 44-57.

 3. A.S. 808253, MKI 24 V 39/00, publ. in B.I. 8, 1981.

 4. A.S. 508391, MKI V 24 V 39/04, 05/21/1976 - the prototype.

Claims (2)

 1. A device for the finishing and hardening of the necks of the crankshafts, comprising a mandrel with a pivotally mounted and spring-loaded fork-shaped holder carrying deforming elements, characterized in that it is equipped with two heads with inserts having spherical grooves, stops fixed to the head housings, one of the ends of each of which is made in the form of a protrusion, the deforming elements are made in the form of balls and are located in the spherical grooves of the liners with the possibility of keeping the said stops from falling out and protrusions of the housings, the heads being mounted at the ends of the fork-shaped holder with the possibility of regulation with the arrangement of the protrusions of their housings asymmetrically to each other, and in the stops and at the ends of the fork-shaped holder, adjustment grooves are made.  2. The device according to p. 1, characterized in that the axis of the balls of one head are offset relative to the axis of the balls of the other head by a = (0.1-1) R, and the distance between the extreme protruding balls of one head and the ends of the body of the other head is determined from relations b = (0.1-0.9) R, where R is the radius of the ball.

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