Method of producing permanent joint

FIELD: process engineering.

SUBSTANCE: external part inner surface is furnished with 2 to 5 mm-pitch teeth. Assembly is carried out to make a clearance between external and internal parts. Internal part is subjected to upsetting.

EFFECT: higher quality and strength of joint, simplified assembly.

4 dwg, 1 ex

 

The invention relates to the automotive industry and is used in the manufacture of blanks for the hubs domestic cars or other parts, transmission torque.

There is a method of Assembly of the parts is carried out by setting with a gap of one part into the hole of the other, followed by heating of a covered part to compensate for the gap between the parts. In the zone of contact between the mating parts perform cylindrical holes and set them in the elastic fixing elements (SU 353808 A1, 09.10.1972).

The disadvantage of this method is the low quality of the Assembly.

Also known way fixed connection of parts, which consists in the fact that the mating surface of one of the connected details place of core elements, which are oriented along the axis of the joined parts and fixed in this position, then assemble the parts by pressing, which provide the implementation of the core elements in the body of the two joined parts. To improve the accuracy of centering of the shaft and sleeve use an even number of beam elements, and the elements of each pair are placed diametrically opposite relative to the axis of the joined parts. Orientation and fixation is carried out, for example, by fixing rod elements in the holes or the PoWPA the descent washer, which is mounted on the end surface of one of the joined parts (EN 2093334 C1, 20.10.1997).

The disadvantages of this method are the most labor intensive method, and hence the high cost of connection and low build quality.

Closest to the proposed invention is a method of permanent connection, namely, that one item is inserted into the other and covering the item compresses by exposure to high pressure working environment. On the inner surface of the covered items are simultaneously affected by the pressure of the working environment, equal in magnitude and oppositely directed pressure exerted on the covering part (SU 389906 A1, 11.07.1993).

The disadvantage of this method is also low build quality, not allowing torque to be transmitted.

The objective of the proposed invention is to provide such a method of permanent connection, which would rule out the shortcomings listed above, and would allow us to create a connection for transmission of large torques.

The technical result achieved by the invention is to provide a permanent connection made in the conditions of stress (over the limit of elasticity) of the status of all components and capable of transmitting torque of 700 N/m (70 KGM), when h is com the quality and strength of the Assembly, and to simplify Assembly and improve the economic performance of the connection.

This technical result is achieved in that in the way of permanent connection for transmitting torque, comprising an Assembly with a gap covering and covered parts and subsequent subsidence covered in detail, while prior to Assembly on the inner mating surface of the covering parts are teeth module 2-5 mm.

The invention is confirmed by the drawings, in which figure 1 shows covered in detail; figure 2 - covering part; figure 3 - connection after precipitation; figure 4 is a photograph connection after precipitation.

The claimed method begins with the preparation of the Assembly parts: 2 covered and cover 1 parts. Covered by item 2 is made from a metal rod, which is cut-to-length harvesting. Covering part 1 are cut from steel sheet in the form of a washer with a hole.

The size of the hole depends on the transmitted connection torque.

On the inner surface of the mating covering parts 1 cut teeth with large module. The size of a tooth depends on the torque and is determined by the empirical formula for crushing spline connection:

where

σcm- voltage failure, kg/mm2 ;

cm] allowable voltage failure, 8-12 kg/mm2;

Mkraj- torque transmitted by the connection kg·mm;

Ψ - coefficient taking into account the uneven distribution of effort (Ψ=1);

F - the area of the side surface of one tooth on one side, mm2;

the number of teeth in the connection units;

rcf.- the average radius of application of force, mm.

The rod is installed in the washer 1 with certain small clearance relative to each other. The prepared compound is placed under a press, such as the stamp of a hydraulic press, and rebuff the rod 2. The force developed by the pressure in welding rod should be sufficient to fill the metal of the tooth at 90-100%. The height of the rod is determined from the condition factor of precipitation 50% and besieged the hub of a specific product.

When more effort is required during bilateral compression occurs disconnection during precipitation. At lower pressures does not fully fill the tooth that later if further processing will lead to the destruction of the connection.

Sludge is carried out in conditions of stress and strain components, in excess of the limit of elasticity. When the strain in the process of precipitation of the workpiece, the average diameter of the rod increases, and p the ducks takes a barrel-shaped. The rod material is distributed in the radial direction on both sides of the washers in the depressions between the teeth up until the contact will not take all the inner mating surface of the washer and the connection will not accept the estimated size of the final product.

The result is a connection 3, which by means of the teeth on the washer and distributed rod material provides strength and ability to transfer torque more than 700 N/m (70 KGM).

When correctly calculated the size of the teeth covering parts, the diameter of the hole and the gap does not fully fill the tooth covered items that drastically reduces the strength of the connections or leads to the destruction of the connection.

Next, the compound obtained is sent for further mechanical processing.

Example. Assembling the detachable connection for the manufacture of the hub.

Cut dimensional procurement covered parts of steel rod - structural steel - circle.

From structural steel sheet cut down covering the workpiece in the form of a washer with a hole 2-4 mm On the inner surface of the washer is cut into large teeth module 2-4 mm.

Details set each other with a certain gap between them and placed the stamp of a hydraulic press.

When the force 180,0 force is sludge rod is emetrol 36 mm in the radial direction on both sides of the washer, when the average diameter is increased to the estimated size and fills in the spaces between the teeth. Thus, a workpiece for the manufacture of the hub.

Next, the resulting billet is directed for further mechanical processing, which resulted in the end product 4 (figure 4).

Correctly calculated size of the hole covered in detail, the size of the teeth and the gap allows permanent connection, obtained by the claimed method, to transmit large torques over 700 N/m (70 KGM), as well as to carry out the claimed method without destroying the parts, i.e. without rejection connection that improves economic performance.

This method simplifies the manufacturing technology of permanent connections, designed for transmission of large torques, excluding preheating of parts or the use of additional parts such as beam elements, which also affects the reduction of the cost price of the finished product.

Simplicity and economic feasibility of the claimed method allows to find a wide application in industry, particularly in the automotive industry, in the manufacture of the hub clutch for domestic cars.

The method of permanent connection, comprising an Assembly with a gap on waywayway and covered parts and subsequent subsidence covered parts thus, before Assembly on the inner mating surface of the covering parts are teeth module 2-5 mm.



 

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1 ex, 1 tbl

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FIELD: machine building.

SUBSTANCE: invention is related to machine building and instrument making, and may be used in performance of machine assembly works. Method for interference fit of parts by means of press fitting with application of material that strengthens the joint includes partial press fitting of parts with measurement of press fitting force and their further additional press fitting. According to method partial press fitting of parts is carried out. Then material that strengthens joint is applied on free sections of joined surfaces of one or both parts. After that their further additional press fitting is realised.

EFFECT: simplification of assembly process and reduction of costs for joint strengthening.

2 dwg

FIELD: process engineering.

SUBSTANCE: external part inner surface is furnished with 2 to 5 mm-pitch teeth. Assembly is carried out to make a clearance between external and internal parts. Internal part is subjected to upsetting.

EFFECT: higher quality and strength of joint, simplified assembly.

4 dwg, 1 ex

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