The method of monitoring the strength of connections with mechanical pressing

 

(57) Abstract:

Usage: in mechanical manufacture for automatic Assembly responsible longitudinally extruded cylindrical joints. The inventive faulty connections are identified by comparison with the limit values of the values of the contact pressure defined for each elementary surface areas of the contact collect press-fit connection. Moreover, to determine the values of contact pressure on all the elementary areas of the contact surface of the connection use a derived Assembly force on the movement of the working body of the press, defined for each elementary step of pressing, and the difference of the diameters of the cylindrical Seating surface of one of the parts of the connection measured for each of the elementary parts of this surface. 3 Il.

The proposed method relates to mechanical engineering and can be used in machining and manufacturing for automatic Assembly responsible longitudinally-pressing cylindrical joints, strength and reliability which are increased requirements.

There is a method of Assembly of caterpillars road is imago connection is controlled by comparing the results of the current value of the pressing force with its maximum permissible values in control points idealized experimental diagrams power move. One control point corresponds to the end of the process apresski cheeks axle and the other end of the process apresski cheeks axle and bushing.

Used in this way to control the strength of the longitudinally-pressing cylindrical connection on the power of the shot at the end of the pressing process has a significant disadvantage in the absence of detection and evaluation of uneven distribution of the contact pressure on the contact surface of the collected compounds. The value of the pressing force at the end of the pressing process allow us to determine only the average value of the contact pressure over the whole formed contact surface. However, the average value of the contact pressure can be from pressure on some areas of the contact surface that is significantly different from the mean in the direction of overstatement and understatement. After Assembly in congested areas is accelerated process of spontaneous removal of excess stress, leading to loss of required strength press-fit connection as a whole, and thus to premature destruction of it in operation.

The closest the m press [2] for which a continuously measured value of the Assembly effort and movement of the working body of the press during pressing with the increase of the nominal surface area of contact is used to control the strength and uniformity of distribution of the contact pressure on the comparison of the continuously determined the values of the derivative of the Assembly's efforts to move the working body with its maximum permissible value, and at the stage of pressing, without changing the nominal surface area of contact is used to control the strength of the collected compounds by comparing the results of the Assembly's efforts with its maximum permissible values for this stage.

However, the control strength and the uniform distribution of the contact pressure, based on the fact that the value of contact pressure on any catchment area of the contact surface is judged only by the value of the derivative of the Assembly's efforts to move the working body at the time of formation of the catchment area of contact surface, and that the distribution of contact pressure over the entire contact surface does not undergo significant changes during pressing with a constant nominal surface area of contact, has the following disadvantage. This control is only valid if the form of a cylindrical Seating surface is close to perfect in the details of the connection, in which the surface longer. This takes into account the deviation of the longitudinal profile of the cylindrical Seating surface only have one connection details, specifically in which the landing surface is shorter. Therefore, the accuracy of control acessem pressing the more, the smaller the deviation of the longitudinal profile of the cylindrical Seating surface details, which this surface is longer, and Vice versa, the control error is significant to the extent that the landing surface of this part differs from the ideal cylindrical shape. Low precision control makes it low quality, because it leads to errors grading collected forging connections.

The objective of the invention is to improve the quality of monitoring the strength of press-fit connection by taking into account the influence of deviations of the longitudinal profile of the cylindrical Seating surfaces of the two parts of the connection on the magnitude and distribution of contact pressure on the contact surface in the axial direction.

This problem is solved due to the fact that the application of the method of monitoring the strength of connections with mechanical pressing, which consists in the continuous measurement of Assembly forces and movement of the working body of the press during the entire build process, and at the stage of pressing, with the increase of the nominal surface area of contact in the definition of the derived Assembly force on the movement of the working body of the press, in addition opredelennoi surface area of contact, break the whole stage of pressing, which results in the formation of the bearing surface contact connection, which is equal to the depth of crimp elementary stages. The value of the derivative of the Assembly force on the movement of the working body of the press is determined for each elementary step of pressing. The entire length of the cylindrical Seating surface of one of the components of the connection are broken down into elementary parts of equal length. Moreover, the length of the elementary section before Assembly set of conditions possible to neglect the deviations of the longitudinal profile of the cylindrical Seating surfaces of the two parts of the connection within this length and depth of the elementary phase offset is equal to the length of the elementary section. In addition, each elementary segment measure the diameter of the cylindrical Seating surface of one of the parts of the connection, determine the difference of diameters for different combinations of the elementary parts. For each elementary area of the contact surface of the connection corresponding to the particular elemental area Seating surface of one of the parts of the connection, determine the value of the contact pressure and the result is pre-built, identify faulty connection.

The proposed method is characterized by a new set of essential features that provide technical result. Split landing surface along its entire length at one of the details of the connection at the elementary parts of equal length, within which we can neglect the deviations of the longitudinal profile of the cylindrical Seating surfaces of the two parts, and split phase offset, which is the coupling on a cylindrical Seating surfaces, at the elementary stages with the same depth offset, equal to the length of the elementary area, allow us to consider the ideal form of a cylindrical Seating surfaces of the parts of the connection within the length of the elementary section, and consequently to idealize the process of fitting within the elementary stage, i.e., to assume a linear dependence of the power Assembly from movement of the working body of the press within each of the elementary stages of pressing.

Traits such as determination of the values of the derivative of the Assembly force on the movement of the working body of the press for each elementary step of pressing on the whole stage m of its elementary parts and the determination of the difference of diameters for different combinations of the elementary parts allow during Assembly to determine the value of the contact pressure for each elementary surface area of contact, within each of which the uniformity of the contact pressure is considered ideal due to the assumptions of ideality form a cylindrical Seating surfaces of the two parts of the connection within the length of the elementary section.

It should be noted that in the prototype with the aim of monitoring the strength of the collected compounds determine the value of the derivative of the Assembly force on the movement of the working body press, but only on the first part of the stage of pressing, but rather at the stage of pressing, with the increase of the nominal surface area of contact. However, due to the fact that the formation of the bearing surface of the contact is carried out at all stages of pressing, the formation of such features quality press-fit connection as strength continues in the second part of this phase, i.e. at the stage of pressing, without changing the nominal surface area of contact. Therefore, the definition of the derivative of the Assembly force on the movement of the working body of the press during pressing without changing the nominal surface area of contact also neophoto Assembly force F of the displacement l of the working body press (or depth offset); in Fig. 2 is a longitudinal section of the safety device with sensor diameter and details of the connection with a schematic depiction of a cylindrical Seating surfaces before pressing, and Fig. 3 is a structural diagram of an automatic press.

The method consists in the following.

Before the start of production of forging connections of this construction aggregate parameters deviations of the longitudinal profile of the cylindrical Seating surfaces of the two parts are press-fit connection. According to the results of statistical processing on the basis of the requirements for the accuracy of monitoring the strength of the connections determine the length l of the elementary area Seating surfaces of the conditions negligibly small influence of deviations of the longitudinal profile of the cylindrical Seating surfaces of the two parts of the connection within the length l of the elementary area on the value of contact pressure. Moreover, the minimum value of the length of the elementary area limited by technical means, the size of the increments used displacement sensor.

The process of manufacturing a cylindrical longitudinal press-fit connection is divided into five stages I V Assembly (Fig. 1).

On SUB>to. Because at this stage there is convergence of the parts without contact with each other, the Assembly force F must satisfy the condition F 0. If the value of assembling a force F is zero, then the build process is aborted.

Phase II build, starting from point Ltoand ending in the point with coordinates of Laboutis centering parts collect connection through their interaction with each other chamfers. As a result of this phase II current value of the Assembly force F will be different from zero and must satisfy the condition Ftowhere Ftothe maximum value of the power Assembly, which may occur when the mutual sliding parts of the compound on the surface of the chamfer. In the case of non-compliance with this condition, the Assembly process is interrupted, and the details collected by press-fit connection rejected.

Phase III Assembly is press-fit to a depth equal to the length of the cylindrical Seating surface of the connection details, which this surface is less long. In the process of pressing is forming a bearing surface contact due to the coupling parts of the connection cylindrical Seating surface is tx2">

At stage IV Assembly pressing continues, but without changing the nominal surface area of contact is equal to the nominal area mounting surface of the connection details, which this surface is less long. Pressing at this stage is carried out to a depth equal to the difference of the lengths of more or less long cylindrical Seating surfaces of the parts of the connection, and ends with the formation of the bearing surface contact.

Thus, the phase offset bounded by the following coordinates: Loand L1consists of stages III and IV Assembly. At this stage produces a simultaneous measurement of the diameter of the cylindrical Seating surface connection details, which this surface is shorter, and the derivative of the Assembly force on the movement of the working body of the press. That these measurements are performed through the same intervals of movement of the working body of the press, equal to the length l of the elementary area is split less long cylindrical surface at the elementary parts of equal length l, and the phase offset at the elementary stages, the depth of pressing each of which is identical and equal to the length l of the elementary section.

For simplicity phoneentry steps 1 to 5 with the same depth l of embedding, and less long cylindrical Seating surface of the sleeve 6 is divided into three basic plot of the same length l (Fig. 2). Therefore, more long cylindrical Seating surface of the shaft 7 can also be divided into elementary parts of equal length l, the number of which equals the number of elementary steps of pressing, i.e. five. When such compositions are phase offset and a cylindrical Seating surface of the sleeve 6 phase III Assembly consists of three basic steps 1 to 3, stage IV Assembly of two basic stages 4 and 5 (Fig. 1).

Until the early elementary stage 1 in the point with coordinates of Landmeasure the diameter of D1the first elemental area of the cylindrical Seating surface of the sleeve 6 (Fig. 1 and 2).

At the elementary stage 1 pressing, limited to points with coordinates Loand l1, there is a pair of elementary sections with diameters of d1and D1cylindrical Seating surfaces respectively of the shaft 7 and the sleeve 6. Change Assembly forces F1at this elementary stage occurs only at the expense of increasing the nominal surface area contact:

F1=DlkTrq11< / BR>
where D is the nominal diameter of the settlement of the kTrcoefficient of friction;

q11the contact pressure at the elementary surface area of contact formed in the pair of the first elementary parts with diameters d1and D1cylindrical Seating surfaces respectively of the shaft 7 and the sleeve 6 connection:

< / BR>
where the stiffness parameter of the details of the connection;

< / BR>
where E1and E2the moduli of elasticity of the material, respectively, the shaft 7 and the sleeve 6;

1and2the Poisson's ratios of the materials respectively of the shaft 7 and the sleeve 6;

dothe diameter of the inner surface of the shaft 7;

Dothe diameter of the outer surface of the sleeve 6.

Due to the possibility of the assumption of the perfect cylindrical shape of the landing surfaces of the parts of the connection within the length l of their elementary parts valid for each elementary step of pressing to equate the ratio F/l to the value of the derivative dF/dl Assembly force on the movement of the working body of the press. With this in mind, the contact pressure is determined using the following expression:

< / BR>
where the value of the derivative of the Assembly force on the movement of the working body of the press, which is set at the elementary stage 1 sapres the exploration of the surface of the sleeve 6 and determine the difference12=D1-D2between the values of the diameters D1and D2accordingly, the first and second elementary parts mounting surface of the sleeve 6. In addition, determine the value of the contact pressure q12at the elementary surface area of contact, which will be established at the elementary stage 2 fitting in the pair of the first elementary area Seating surface of the shaft 7 with a diameter of d1and second elementary area Seating surface of the sleeve 6 with a diameter of D2:

< / BR>
Values of q11and q12compare with the top edge of Qmaxfield tolerance to the contact pressure. If these values of contact pressure q does not satisfy the condition qmaxthe Assembly process is interrupted, and collect the connection is rejected.

At the elementary stage 2 pressing, limited to points with coordinates l1and l2, there is a pair of elementary sections with diameters of d1and D2d2and D1cylindrical Seating surfaces respectively of the shaft 7 and the sleeve 6. Change Assembly forces F2at this elementary stage occurs at the expense of increasing the nominal surface area of contact of Yes is th surface of the sleeve 6 with a diameter of D1with the values of q11the value of q21:

< / BR>
where q21the contact pressure at the elementary surface area of contact formed in the pair of the second elementary area Seating surface of the shaft 7 with a diameter of d2and the first elementary area Seating surface of the sleeve with a diameter of D1:

< / BR>
q22the contact pressure at the elementary surface area of contact, which will be established at the elementary stage 3 fitting in the pair of second elementary parts with diameters d2and D2Seating surfaces respectively of the shaft 7 and the sleeve 6:

< / BR>
At this elementary stage, determine the value of the derivative of the Assembly force on the movement of the working body press, measure the diameter of D3the third basic area Seating surface of the sleeve 6, which are used to determine the difference 13and23between its value and the values of the diameters D1and D2accordingly, the first and second elementary parts mounting surface of the bushing 6:

23=D2-D3;

13=D1-D3=23.

Then specify the following values kontak contact which will be established at the elementary stage 3 fitting in the pair of the first elementary area Seating surface of the shaft 7 with a diameter of d1and the third basic area Seating surface of the sleeve 6 with a diameter of D3:

< / BR>
where q23the contact pressure at the elementary surface area of contact, which will be established at the elementary stage 4 fitting in the pair of the second elementary area Seating surface of the shaft 7 with a diameter of d2and the third basic area Seating surface of the sleeve 6 with a diameter of D3.

Values of q22, q21, q13, q23the contact pressure q must satisfy the condition qmax. In case of failure to fulfill this condition the Assembly process is interrupted and collect the connection is discarded.

At the elementary stage 3 pressing, limited to points with coordinates l2and l3, there is a pair of elementary sections with diameters of d1and D3d2and D2d3and D1cylindrical Seating surfaces respectively of the shaft 7 and the sleeve 6. Change Assembly forces F3at this elementary stage there's lots of contact surface, corresponding to the first and second elemental areas of the Seating surface of the sleeve 6, with a value of q21for q31and with the values of q12and q22respectively:

< / BR>
where q31the contact pressure at the elementary surface area of contact formed in the pair of the third elementary area Seating surface of the shaft 7 with a diameter of d3and the first elementary area Seating surface of the sleeve 6 with a diameter of D1:

< / BR>
q33the contact pressure at the elementary surface area of contact, which will be established at the elementary stage 5 offset in the pair of third elementary parts with diameters d3and D3cylindrical Seating surfaces respectively of the shaft 7 and the sleeve 6:

< / BR>
At this elementary stage, determine the value of the derivative of the Assembly force on the movement of the working body of the press, which are used to determine the following values of contact pressure:

< / BR>
< / BR>
< / BR>
where q32the contact pressure at the elementary surface area of contact, which will be established at the elementary stage 4 fitting in the pairing of the third element of the second surface of the bushing 6 with a diameter of D2.

Values of q33, q31, q32the contact pressure q must satisfy the condition qmax. In addition, the value of q33compared even with a lower bound of Qminfield tolerance to the contact pressure and must satisfy the condition q33Qmin. In case of failure to meet these conditions, the Assembly process is interrupted, and collect the connection is rejected.

At the elementary stage 4 pressing, limited to points with coordinates l3and l4, there is a pair of elementary sections with diameters of d2and D3d3and D2d4and D1cylindrical Seating surfaces respectively of the shaft 7 and the sleeve 6. Change Assembly forces F4at this elementary stage only occurs due to a change in contact pressure at the elementary areas of contact surface corresponding to the first, second and third elementary areas of the Seating surface of the sleeve 6, with a value of q31for q11with the values of q22for q32and with the values of q13for q23respectively:

< / BR>
or

< / BR>
where q41the contact pressure at the elementary surface area of contact formed in resultelements area Seating surface of the sleeve 6 with a diameter of D1:

< / BR>
the value of the derivative of the Assembly force on the movement of the working body of the press at the elementary stage 4 fitting.

Defined at this elementary stage, the value of the derivative is used to determine the following values of contact pressure:

< / BR>
< / BR>
where q42the contact pressure at the elementary surface area of contact, which will be established at the elementary stage 5 offset in the pair of the fourth elementary area Seating surface of the shaft 7 with a diameter of d4and second elementary area Seating surface of the sleeve 6 with a diameter of D2.

The value of the contact pressure q41must satisfy the condition q41Qmaxand the value of q42the condition Qminq42Qmax. In case of failure to meet these conditions, the Assembly process is interrupted, and collect the connection is rejected.

At the elementary stage 5 pressing, limited to points with coordinates l4and L1, there is a pair of elementary sections with diameters of d3and D3d4and D2d5and D1cylindrical Seating surfaces respectively of the shaft 7 and the sleeve 6. Change with the elementary parts of the surface of contact, corresponding to the first, second and third elementary areas of the Seating surface of the sleeve 6 with the values of q41for q51with the values of q32for q42and with the values of q23for q33.

< / BR>
or

< / BR>
where q51the contact pressure at the elementary surface area of contact formed in the pair of the fifth elementary area Seating surface of the shaft 7 with a diameter and the first elementary area Seating surface of the sleeve 6 with a diameter of D1:

< / BR>
the value of the derivative of the Assembly force on the movement of the working body of the press at the elementary stage 5 offset.

Defined at this elementary stage, the value of the derivative is used to determine the value of the contact pressure q51:

< / BR>
The value of the contact pressure q51must satisfy the condition Qminq51Qmax. In case of failure to fulfill this condition the Assembly process is interrupted, and collect the connection is rejected.

Thus, to determine the values of contact pressure at all elementary stages of pressing, use the following mathematical relationship is recorded in the General form:

< / BR>
mu elementary section of the Seating surface of the sleeve 6 and is formed in the pairing of this part of the sleeve 6 and the i-th elementary area Seating surface of the shaft 7 to (i+j-1)-th elementary phase offset;

the value of the derivative of the Assembly force on the movement of the working body press on the i-th elementary phase offset;

Bijthe value of the auxiliary values corresponding to the value of the contact pressure qij;

indexes;

n the number of elementary steps of pressing, or the number of elementary segments on the cylindrical Seating surface of the shaft 7;

m number of elementary segments on the cylindrical Seating surface of the sleeve 6.

The auxiliary value is determined using one of the following dependencies:

< / BR>
whereij=Di-Djthe difference between the diameters respectively of the i-th and j-th elementary parts mounting surface of the sleeve 6;

q(i-m)jthe contact pressure at the elementary surface area of contact formed in the pair (i, m)-th elementary area Seating surface of the shaft 7 with a diameter of d(i-m)and the j-th elementary area Seating surface of the sleeve 6 with a diameter of Dj.

All values of contact pressure compared to the upper bound Qmaxfield tolerance to it. The values of contact pressure qijfor indexes which true equality i what arnom stage of pressing, additionally compare and with a lower bound of Qminfield tolerance to the contact pressure. If the values of the contact pressure does not go beyond established for them the boundaries, then the build process continues.

On the V stage of Assembly, located between the points with coordinates L1and L2is finish pressing, which is due to the interaction of parts to be assembled, 6 and 7 the ends is characterized by a sharp increase in the Assembly of the force F to its maximum permissible values of Fmax. As soon as the Assembly force reaches its maximum value, Fmaxfor mounting, the Assembly process ends. The working body of the press must be within this stage of Assembly, i.e., must run the following condition:

< / BR>
If this condition is not met, then the collected press-fit connection rejected.

The proposed method can be implemented, for example, by means of an automatic press. Automatic press (Fig. 3) consists of a block of 8 job status, block 9 set the interval, block 10 task forces, block 11 job pressure, four blocks 12 15 comparison unit 16 of differentiation, the counting block 17, block 18 controls that can realitytv 2C 42. Technical description 1 LANG. 035.080. THEN; computer electronics 60" 15 VM 16. Technical description 2.791.004. THEN, the actuator 19, for example ST, engine 20 DC, for example, the WSP 112L, sensor 21 moves, such as electro-optic rotation sensor IRC 111, mechanism 22 moves, for example, transmission screw-nut rolling, the working body of the press in the form of a plug 23, a sensor 24 of a diameter, for example of the Converter with two probes (see Roundmeter type KD, model 290. Technical description 290.0.00.00. PS; the Converter. Technical description 290.7.00.0.00. THEN, the sensor 25 forces, for example magnetoelastic sensor compressive efforts, the DMA-1, the transducer 26, such as rack "CAMAS", device 27, the receiving element 28 of the force sensor (Fig. 2).

The sensor 24 diameter stationary mounted in the device 27, which is spring-loaded and movable in the axial direction relative to the receiving element 28 of the force sensor. The outputs of the sensor 24 in diameter and sensor 25 power connected respectively to first and second inputs of the Converter 26. The first output of the Converter 26 is connected to the third input of the counting unit 17, and the second input with the second input of the second unit 13 comparison unit 16 of differentiation. The output of the sensor 21 move connected with PE is to be placed. The output unit 8 to set the position connected to a second input of the first unit 12 comparisons. The output unit 9 set the interval connected with a second input of the third block 14 comparisons. The first output of the first block 12 comparison connected to the first input unit 18 of the control, the second output with the input unit 10 task forces, the third output to the first input of the third block 14 of the comparison, the output of which is connected to the first input of the counting unit 17. The output of block 10 task forces connected to the first input of the second unit 13 of the comparison, the output of which is connected to the second input of the control block 18. The outputs of the counting unit 17 and unit 11 job pressure connected respectively with the first and second inputs of the fourth comparison unit 15, the output of which is connected with the third control block 18. The output of the control block 18 is connected to the input of the actuator 19. The output of the drive 19 is connected to the engine 20 DC. The motor shaft 20 is kinematically connected with the shaft of the sensor 21 of the moving mechanism 22 moves, for linearly moving element are rigidly mounted punch 23. Through the shaft 7 and the sleeve 6 collect connection plug 23 kinetically associated with the receptive element 28 of the sensor 25 forces, and through the shaft 7 with the safety device 27. The landing surface is with works as follows.

After the reset command on the beginning of the Assembly, the actuator 19 includes a motor 20, a rotation shaft which is transmitted to the shaft sensor 21 move and is converted by the mechanism 22 to move in the forward movement of the plunger 23 with the installed shaft 7 collect connection. During Assembly, the shaft 7 with its end acts on the end face of a spring-loaded safety lock 27, moving it together with mounted therein a sensor 24 of a diameter relative to the sleeve 6 of the connection in the axial direction. When the probe sensor 24 diameter slide on a cylindrical Seating surface of the sleeve 6 from one cross section to another. In addition, since the probe shaft 7 and the sleeve 6 of the Assembly force F developed by the punch 23 press through the shaft 7 and the sleeve 6 pre-mounted on the receiving element 28 of the sensor 25 force acts on the elastic element of the sensor 25. Analog signals from the sensor 24 in diameter and sensor 25 forces are transferred by the Converter 26 into a digital form, acting on its first and second outputs, respectively. The rotation sensor 21 movement causes its output signal, which carries information about the current value of the position l of the plug 23 of the press. In the first the seven units of the provisions of the punch 23, the corresponding coordinates of points Ln, Lto, Lo, L1, L2boundaries of Assembly steps and point Lnthe measurement of the diameter of the sleeve 6 (Fig. 1). Information about the meaning of these settings is entered in block 8 job position prior to Assembly. In moments equality sensor signal 21 position with the setpoint position of the plug 23 of the first block 12 comparison generates control signals. The signal from the second output unit 12 in the block 10 task force will use one of three settings maximum allowable Assembly forces. Phase I of the build process uses the setpoint is zero, phase II Assembly with a value of Ftothat combined phases II, IV and V of the Assembly with a value of Fmax. In the second block 13 compare the current value of the Assembly of the force F, which is supplied from the second output of the Converter 26, compared with involved at this time, by setting the maximum allowable value of the Assembly force. When enabled, the setpoint becomes smaller, the second block 13 comparison sends a signal to the control block 18, which in turn signals the presence of marriage and submits to the actuator 19 a stop and reverse the motor 20. At the moment of equality signee internal diameter of the sleeve 6, the first block 12 comparison in the third block 14 comparison comes allowing his work team. In turn, the third block 14 of the comparison is sent to the counting unit 17, the signal recording information about the value of inner diameter received in the counting unit 17 from the first output transducer 26. Previously entered in block 9 set the interval setpoint corresponding to the interval l of movement of the punch 23, in the third block 14 comparison are compared with the signal of the sensor 21 is moved. At equality this setpoint value change of the sensor signal 21 move since the start of the third block 14 compare it sends a signal that allows the recording of information about the values of the internal diameter of the sleeve 6 and the derivative of the Assembly force on the movement of the punch 23. Further, a similar signal is sent to the counting unit 17 at equality setpoint interval l move the plug 23 with the change of the sensor signal 21 move from the submission of the previous signal, the third block 14 comparisons. The current value of the derivative dF/dl is determined in block 16 of differentiation on the basis of information on the movement l of the punch 23 and the current value of the Assembly force F received by the block 16, respectively, and the unit 17. In the counting unit 17 determines all the difference in values of the internal diameter of the sleeve 6 and the values of contact pressure that can be calculated using the information recorded in this block 17 to this point in time. In the fourth block 15 comparison of each of the specific values of the contact pressure is compared with a setpoint corresponding to the boundary values of Qminand Qmaxfield tolerance to the contact pressure and entered in block 11 of the set pressure before the build. If the value of the contact pressure is outside the tolerance limits on it, the fourth comparison unit 15 sends a signal to the control block 18, and he, in turn, signals the presence of marriage and submits to the actuator 19 a stop and reverse the motor 20. A similar command is a control block 18 after enrolling in this unit 18 of the first block 12 comparison at the moment of equality sensor signal 21 move with setpoint corresponding to the coordinate of the extreme points of L2the operating position of the plunger 23. Moreover, the unit 18 of the control signals the validity of the collected connection only if the signal from the second block 13 comparison of exceeding the current value of the Assembly force F above the maximum allowable value is sa within the boundaries of L1and L2phase V of the Assembly.

When reverse rotation of the motor shaft 20 and the drain plug 23 to the initial position in the first block 12 comparing the sensor signal 21 position is compared with the setpoint corresponding to the coordinate of the Lnthe initial position of the punch 23, and at the moment of equality of the first block 12 comparison unit 18 of the control signal. On the basis of this signal, the control block 18 gives a command to the actuator 19 to the stop of the engine 20. In the Assembly process the next connection cycle automatic press repeats.

The use of the proposed method of monitoring the strength of connections with mechanical injection compared with the prototype allows to increase the accuracy of determining the contact pressure due to the accounting impact on its magnitude and pattern of distribution along the length of the contact surface deviations of the longitudinal profile of the cylindrical Seating surfaces of the two parts of the connection. Increase quality control strength longitudinally extruded cylindrical connections, because the reduced number of cases of inadequate design in the form of manufactured marriage and erroneously rejected accepted connections. In addition to that is you can use it and for those compounds, have the two parts, not one, have a cylindrical Seating surfaces with deviations of the longitudinal profile, significantly affecting the contact pressure. Therefore, the way you do not have to spend time and money on advanced precision machining parts with a longer cylindrical Seating surface to obtain this surface with minor deviations of the longitudinal profile.

The method of monitoring the strength of connections with mechanical pressing parts with a cylindrical Seating surface, which consists in the fact that the Assembly process is continuously measured values of the Assembly effort and movement of the working body of the press, characterized in that it further cylindrical Seating surface of one of the joined parts throughout its length divided into elementary parts of equal length, which is pre-set from the condition of possibility of neglecting the deviations of the longitudinal profile of the cylindrical Seating surfaces of the two parts of the connection within this length, measure the diameter of each of the elementary areas cylindrical Seating surfaces, determine the difference of the diameters for the difference is awnie depth of crimp elementary stages, the depth of fitting of each of which are equal to the length of the elementary section of the cylindrical Seating surface, the derivative of the Assembly's efforts to move the working body of the press is determined for each of the elementary stages of pressing, for each elementary area of contact surface corresponding to a particular elemental area of the cylindrical Seating surface connection details, and the derivative determines the contact pressure, which is compared with its maximum permissible values.

 

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FIELD: repairing equipment of shops, namely of locomotive depots of railway road transport vehicles.

SUBSTANCE: movable installation includes lifting table having lower wheeled platform and jointly mounted on it upper stand; mechanism for lifting and descending said stand; power hydraulic cylinder mounted on upper stand and communicated by means of hydraulic lines through control unit with high-pressure pump system; clamping device for mounting-dismounting bearing assemblies. High pressure pump system includes tank, pump aggregate, draining pipeline, suction pipeline connecting inlet of pump aggregate with tank. Lifting and descending mechanism is in the form of hydraulic cylinder and it is mounted on lower platform. Pump aggregate is arranged on upper lid of tank and it is in the form of displacement hydraulic pump with electric motor. Filter is mounted in suction pipeline. Control unit is in the form of body having two built-in safety valves, tap distributor and built-in non-return valve. Manometer and additional filter connected with draining pipeline and having pouring hole are connected with control unit. Hydraulic lines are in the form of flexible hoses. Installation is provided with additional power hydraulic cylinder that forms together with connected in parallel main hydraulic cylinder unit of power hydraulic cylinders. Said unit of power hydraulic cylinders is placed on supporting sheet-plate mounted on upper stand with possibility of rotation or removal from upper stand and with possibility of moving in range of length of flexible hoses. Similar cavities of hydraulic cylinders are mutually communicated. Clamping device includes movable and stationary plates mounted respectively on rods and back lids of hydraulic cylinders and designed for joining tie rods of attachment.

EFFECT: enhanced reliability, no-failure operation of installation.

10 dwg

FIELD: assembling of precise units of instruments by pressing-in with use of calibrated effort, by riveting and expanding with use of precession tool.

SUBSTANCE: press includes П-shaped housing; adjustable table mounted in struts of housing and fixed to said struts by means of pins; power hydraulic cylinder with axial motion of rod; rotation drive of precession head; pumping station of hydraulic drive unit. Rotation drive of precession head includes electric motor and belt transmission. Power hydraulic cylinder is rigidly mounted on cross piece of housing and it carries plate on end of spring-loaded rod. Said plate supports two plungers spaced in parallel relative to axis of rod and spring-loaded relative to housing. Pulleys of belt transmission of rotation drive are mounted in casing. The last is secured to plate in such a way that driven pulley is mounted on spindle coaxially relative to rod of hydraulic cylinder and driving pulley is mounted on the same axis as shaft of electric motor placed in cross piece of housing. Driving pulley and shaft of electric motor are kinematically joined by means of other shaft whose one end is mounted in shaft of electric motor and whose other end is joined by means of sliding dowel with opening of supporting axle of driving pulley. Spindle of driven pulley is joined with precession head.

EFFECT: improved design providing enhanced rigidity and working accuracy of press.

4 dwg

FIELD: mechanical assembling procedures, namely equipment for assembling aggregates of caterpillar transport vehicles, for example semiautomatic machines for assembling caterpillar tracks.

SUBSTANCE: in apparatus for assembling chain stop plate is mounted in such a way that its working surface is arranged in plane normal relative to pressing in plane. Upper non-working portion of stop plate at side of ending pressing-in cycle is inclined in horizontal plane to side from rotor type conveyer. Lower non-working portion of plate in vertical plane is inclined relative to vertical line to side from rotor type conveyer. Stop part of pusher exceeds diameter of head of pin. Rigid guides are arranged in plane parallel to pressing-in plane; said guides are in the form of roller tables with pitch between rollers of roller table less than pitch of chain links. Guides embrace upper branch of conveyer from downwards and branch of chain from upwards at least along the whole length of it. Drive unit is provided in addition with back-stroke mechanism. Splitter is in the form of plate that is jointly mounted in its mean portion along lateral sides on supporting surface in horizontal plane along motion direction of conveyer for moving pins and it forms two-arm lever. One end of said lever is spring-loaded from downwards with possibility of engaging with dents of conveyer for moving pins. Other end of said lever is Г-shaped one and it may engage by free end with pins on inclined trough. Horizontal axes of articulation joints in vertical plane are provided with holding levers rigidly joined with plate and mounted with possibility of engaging with pins on inclined trough.

EFFECT: enlarged manufacturing possibilities, enhanced operational reliability.

7 dwg

Mandrel // 2258591

FIELD: mechanical engineering.

SUBSTANCE: mandrel has guide, working part made of deformable teeth, calibration parts, and diverging groove made in the guide and working parts. The expanded end of the groove is in coincident with the origin of the guiding part. The groove that ends at the last deformable tooth of the working part has radius-shaped cross-section.

EFFECT: enhanced quality of the press joint and expanded functional capability.

2 dwg

FIELD: machine engineering, namely equipment for dismounting press-fit joints, possibly restoration of electric machines.

SUBSTANCE: apparatus includes housing with platforms for horizontal and vertical motions. Part to be dismounted is placed on horizontal motion platform and it is fed to stripping mechanism. The last is joined with vertical motion platform by means of fastening members and it is provided with adjusted grips supporting heating members with possibility of their axial movement. Heating members are in the form of nozzles for alternating feed of hot and cooled air.

EFFECT: reduced axial errors between dismounted part and stripping mechanism, lowered efforts for stripping parts.

5 cl, 5 dwg

FIELD: mechanical engineering.

SUBSTANCE: device comprises the mechanism for locking pressed parts made of an extensible sleeve. The first power hydraulic cylinder is used for moving parts and can rotate between two vertical unmovable pillars. The pillars are pivotally connected in pair with movable vertical pillars through the top and bottom horizontal clamps. The extensible spring-loaded stop with the drive and the first hydraulic cylinder are axially aligned. The first power hydraulic cylinder receives the second power hydraulic cylinder whose rod is provided with first center and spring. One end of the spring co-operates with the piston, and other end of the spring co-operates with the face of the extensible sleeve. The extensible stop receives the second center with the stack of plate springs that is coaxial to the first center. The bottom clams are provided with a lifting-rotating device.

EFFECT: reduced labor consumption for making and simplified structure.

1 cl, 2 dwg

Crank stripper // 2267397

FIELD: devices designed for simplifying procedures of assembling/disassembling units.

SUBSTANCE: crank stripper includes cross piece 1 supporting power mechanism in the form of one-way telescopic hydraulic cylinder 2 having thrust rod 3 for shaft of crank 14; mechanism for forced closing of foots having cylindrical discs 8, 9, paired plates 10 and double-arm levers 4,5. One arm is used for engaging with crank; other arm of is cone one and it may rest upon lateral surface of cylindrical disc secured to lateral side of cross piece. Double-arm lever whose arms are mutually inclined by obtuse angle is jointly mounted through paired plates in center of disc. Articulation joint of lever is mounted in edge portion of second lever arm on line of inner surface of first lever arm.

EFFECT: intensified clamping of part by foots, enhanced efficiency, lowered cost price of working operations.

2 dwg

FIELD: mechanical engineering.

SUBSTANCE: method comprises gripping the part to be dismounted and applying axial load by means of at least two ties and, e.g., hydraulic cylinder. The rod of the hydraulic cylinder cooperates with the face of the shaft. The ties are interconnected via a plate opposite to the end of the part to be dismounted. Each of the ties is provided with the eccentric groove. The ties are set in the openings in the part to be dismounted for permitting engagement by their step defined by the eccentric groove. Between the wall of the opening of the part to be dismounted and each tie is sickle-shaped bushing member. The hydraulic cylinder abuts against the plate so that to provide relationships D1 ≤ D2, b ≥ H, e = h, where D1 is the outer diameter of the tie, D2 is the diameter of the opening in the part to be dismounted, b is the width of the eccentric groove, H is the thickness of the part, e is the eccentricity of the groove with respect to the axis of the tie, and h is the maximum thickness of the sickle-shaped bushing member.

EFFECT: expanded functional capabilities.

1 cl, 2 dwg

Stripper // 2271922

FIELD: machine engineering, namely mechanical strippers.

SUBSTANCE: stripper includes traverse bar with grips, screw having two outer threads with different pitches; main detachable sleeve mounted by thread whose pitch is less than that of said screw; additional threaded sleeve mounted by second thread of said screw; holder embracing both sleeves, fixed relative to them in angular direction and resting by its inner shoulder upon end of main sleeve. Inner shoulder is formed on one end of holder; other open end of holder is arranged in through opening of traverse bar and it is rigidly joined with said bar. Threads of powerful screw have similar sign; additional sleeve has outer flange spaced from open end of holder by interval determined according to relation K = B1(H2/H1 - 1), where K - interval between outer flange of additional sleeve and open end of holder; B1 - displacement (caused by main sleeve) of part stripped by means of stripper; H2 - thread pitch of additional sleeve; H1 - thread pitch of main sleeve. Sleeves are mutually spaced by interval T exceeding value of mutual convergence of sleeves.

EFFECT: simplified usage of stripper.

1 dwg

FIELD: railway road machine engineering, possibly repairing of railroad machines.

SUBSTANCE: press includes frame having base and two struts mutually joined by means of two columns; working cylinder mounted on one of said struts; force and supporting traverse bars with rollers. Said traverse bars are arranged between struts of press frame and they are mounted with possibility motion on rollers along columns of power frame. Force traverse bar is mounted with possibility of fixing it to columns.

EFFECT: enlarged manufacturing possibilities, improved quality of combining wheel pairs, simplified design of press.

6 cl

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