CN105588711B - Distance rod bolt experimental rig - Google Patents

Abstract

The invention discloses a kind of distance rod bolt experimental rig, including：Test sleeve, experiment backing plate, two anti-rotation levers and fixing nut；And two anti-rotation levers are arranged on experiment sleeve by fixing nut；The experiment backing plate is arranged on two anti-rotation levers；Wherein, there is an opening above the experiment sleeve, and penetrated with its interior bone, multiple experiment backing plates can be installed on the anti-rotation lever, can not also be installed.The distance rod bolt experimental rig of the present invention can be according to the length of tested distance rod bolt, the different experiment backing plate of installation number, so as to adapt to the tested bolt of different length.

Description

Thrust rod bolt test device

technical field

The invention belongs to the field of mechanical design of non-standard parts, in particular to a test device for detecting the pretightening force of thrust rod bolts.

Background technique

Balanced suspension is widely used in heavy-duty vehicles. It improves the grounding performance of heavy-duty vehicles, especially heavy-duty special-purpose vehicle tires, and ensures the balance of loads between two or more bridges under various working conditions. In the two-bridge balanced suspension, the leaf spring distributes the load evenly to the middle and rear axles. It can only transmit vertical force and lateral force, but cannot transmit traction force, braking force and related moments. Therefore, the middle and rear axles are equipped with The upper thrust rod and the lower thrust rod are used to transmit longitudinal load and moment. With the implementation of the domestic axle load law and the implementation of "toll by weight", trucks are developing in the direction of heavy-duty, box-type, and traction-oriented.

At present, trucks mainly increase the carrying capacity by increasing the number of axles (axles) or the bearing capacity of axles (axles). The thrust rod of the guide mechanism is one of the three key components of the balanced suspension. Another function of the thrust rod in the balance suspension is to prevent the displacement of the axle. Generally, the straight thrust rod can only prevent the front and rear displacement of the middle and rear axles, while the V-shaped thrust rod can not only prevent the front and rear displacement of the middle and rear axles, but also prevent the displacement of the middle and rear axles. It can prevent left and right displacement, because when the car is turning, the middle and rear axles may have the problem of left and right displacement, which will cause friction between the leaf spring and the tire.

The lateral thrust bar, we also call it the anti-roll bar, is an auxiliary component in the suspension system. Its main function is to prevent too much lateral roll of the body when turning, causing unnecessary traffic accidents, so the main purpose of the lateral thrust rod is to prevent the lateral overturning of the car and improve the balance of the car. The lateral thrust rod is a torsion bar spring supported by spring steel, which is in the shape of a "U" and placed horizontally on the rear axle of the car. The middle part of the thrust rod body is hinged to the vehicle frame with a sleeve, and the two ends of the thrust rod are respectively fixed on the left and right suspensions. When the body moves vertically, the suspension on both sides deforms the same, and the lateral thrust rod does not work. When the body rolls, the suspension on both sides jumps inconsistently, the lateral thrust rod will be twisted, and the elastic force of the rod body will become the resistance to the car's roll, and finally play a role in lateral stability.

To sum up, the thrust rod can not only transmit the longitudinal force, withstand the reaction moment caused by the braking force, but also prevent the vehicle from overturning during the turning process, so its role in the suspension is very important. Because it is connected with the balance suspension, frame, axle and other parts through the thrust rod bolts, its assembly quality directly affects whether the thrust rod can work normally and plays a role in stabilizing the vehicle body.

In recent years, with the advancement of material science and the improvement of processing technology, the mechanical properties of thrust rod bolts have been significantly improved, and the traditional installation methods can no longer give full play to their potential mechanical properties. Therefore, it is necessary to test the torque and preload of the thrust rod bolts to understand their mechanical properties. However, there is currently a lack of equipment to detect the stress of the thrust rod bolts during the pre-tightening process, so it is impossible to effectively detect the stress state of the thrust rod bolts, so that it cannot effectively improve its assembly stress state and improve its reliability. Sex, which is very detrimental to improving the quality of assembly.

Contents of the invention

In order to solve the above problems, the present invention provides a test device that can conveniently detect the pretightening force on the thrust rod bolts during installation.

The technical scheme that the present invention adopts is as follows:

A thrust rod bolt test device, comprising: a test sleeve, a test backing plate, two anti-rotation levers and a fixing nut;

The main body of the test sleeve is a cylinder, and an internal through hole is drilled in the center to pass through the thrust rod bolts. At both ends of the test sleeve, an ear protrudes to both sides, and on the ear There is a through hole, the anti-rotation lever is installed in the through hole of the ear, an opening above the test sleeve is connected with the internal through hole, and the wire of the strain gauge can pass through;

The two anti-rotation gear rods are fixed on the test sleeve through the fixing nut, and are in the shape of a stepped shaft, consisting of two sections of cylinders with different diameters. The thinner section penetrates into the ear holes on both sides of the test sleeve , and its end is also designed with threads, which can be installed on the test sleeve with fixing nuts; the thicker section is used to install the test backing plate, and the anti-rotation rod passes through both sides of the test backing plate through holes, and prevent the test device from rotating during the test;

The test backing plate is installed on the two anti-rotation gear levers through the through holes on both sides. On the thick section of the two anti-rotation gear levers.

Preferably, it also includes two protective pads, which are in the shape of a ring, and are respectively installed on the two side end faces of the test sleeve or the test backing plate.

A plurality of test backing plates are installed on the anti-rotation gear lever.

The anti-rotation gear lever is installed on both sides of the tightening machine fixing nut sleeve.

The material of the test sleeve and the test backing plate is the same as that passed through the thrust rod.

Compared with the prior art, the thrust rod bolt test device of the present invention has the following advantages: due to the number of test backing plates can be adjusted according to different vehicle models, to adapt to thrust rod bolts of different lengths; There are openings, which can facilitate the detection equipment to collect the elongation of the thrust bolt during the tightening process through the corresponding sensor, and then obtain the change of the pretightening force on the bolt.

The present invention is applicable to all types of thrust rods. Since they are all connected by bolts, the quality of the bolt connection between the tested thrust rods and the brackets is problematic, so it has little relationship with the shape of the thrust rods.

Description of drawings

Fig. 1 is a schematic structural view of the thrust rod bolt testing device of the present invention.

Fig. 2 is a cross-sectional view of the thrust rod bolt testing device of the present invention.

Fig. 3 is the external schematic diagram of the test plate of the invention.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Fig. 1 is a schematic structural view of the thrust rod bolt testing device of the present invention.

As shown in Figure 1, the thrust rod bolt test device of the present invention is used to clamp the thrust rod bolt when utilizing relevant detection instruments to perform performance tests on the thrust rod bolt, that is, as a test platform during the detection test, it may include a test sleeve 2. Test backing plate 4, two anti-rotation gear levers 7 and fixed nut 1; the two anti-rotation gear levers 7 are installed on the test sleeve 2 through the fixing nut 1; the test backing plate 4 is installed on two On the anti-rotation lever 7.

The main body of the test sleeve 2 is a cylinder, and an internal through hole is drilled in the center for passing through the thrust rod bolts. At both ends of the test sleeve, an ear protrudes to both sides respectively. There is a through hole, the anti-rotation lever is installed in the through hole of the ear, an opening above the test sleeve is connected with the internal through hole, and the wire of the strain gauge can pass through;

The two anti-rotation gear rods 7 are installed on both sides of the fixing nut sleeve of the tightening machine, and are placed on the test sleeve through the fixing nut. It is in the shape of a stepped shaft and consists of two sections of cylinders with different diameters. The thinner section penetrates into the test sleeve. In the ear through holes on both sides of the test sleeve, the end is also designed with threads, which can be installed on the test sleeve with a fixing nut; the thick section is used to install the test backing plate, and the anti-slip The shift lever passes through the through holes on both sides of the test pad, so that multiple test pads can be installed at one time and prevent the test device from rotating during the test;

The main body of the test backing plate 4 is in the shape of a ring, with ears protruding from both sides, each of which has a through hole, and the through hole is installed on the thick section of the two anti-rotation gear levers.

In the present invention, two protective gaskets 5 are also included, which are respectively installed on the two side end faces of the test sleeve 2 or on the test backing plate. Effectively protect the end face of the protective sleeve and the test backing plate from the wear of the bolt or nut of the thrust rod under test, so that the test sleeve and the test backing plate can be reused, since a new protective gasket must be replaced in each test, Therefore, the accuracy of the test can be guaranteed. However, the protective gasket 5 needs to be replaced after each tightening process. At the same time, due to the corresponding treatment of the protective gasket 5, its roughness and surface hardness are relatively consistent, so that the consistency of the data obtained from the same batch of bolts and nuts is better, and the data obtained from different batches of bolts and nuts are comparable.

In the present invention, an opening 3 is processed on the upper side of the test sleeve 2 and communicates with the internal through hole. After the thrust rod bolt penetrates the test sleeve, it is exposed at the opening, and the strain gauge can be pasted more conveniently to measure the bolt pre-tightening force. The function of the strain gauge is to measure the elongated deformation of the thrust rod bolt after being stressed, and multiply the deformation by the elastic modulus of the material to obtain the stress value of the bolt. It is a commonly used method to measure the force of parts.

In the present invention, multiple test pads 4 may be installed on the anti-rotation gear lever 7 at a time, or may not be installed. The main reason for using the test pad is that the length of the thrust rod bolts to be tested is different, and the range of variation is large. In order to make a test sleeve suitable for thrust rod bolts of different lengths, a number of test pads with different thicknesses are correspondingly designed. plate. The end faces of these backing plates are identical in shape, differing only in thickness. During the test, gaskets of different thicknesses are combined and added to one side of the test sleeve according to the length of the bolts, and the total added thickness is subject to the normal tightening of the nuts. In order to make it easy to install and ensure that it will not rotate with the bolt or nut during the tightening process, the symmetrical holes on both sides, i.e. the ear through hole 8, are worn on the anti-rotation gear lever 7. The large hole in the center, that is, the internal through hole 9, is used for passing the measured bolt.

In the present invention, the anti-rotation gear lever 7 is installed on both sides of the tightening machine fixing nut sleeve 6 . Its end is processed with a nut, and after it is installed on the test sleeve 2, it is tightened by the nut 1.

In the present invention, the materials of the test sleeve and the test backing plate are selected according to the test requirements. Specifically, the selection is based on the material of the connected parts at the bolt installation position. The elastic modulus and hardness of the selected material should be consistent or similar. Due to the different manufacturing materials of different thrust rods, the material of the test sleeve needs to be consistent with the actual parts, and the choice of the material of the test backing plate is the same. For example, if the thrust rod is made of cast steel, then the test sleeve or test backing plate should also be cast steel.

When working, the two anti-rotation levers 7 are respectively mounted on both sides of the fixing nut sleeve 6 of the tightening machine. When the bolt tightening machine drives the bolts to rotate, the anti-rotation levers 7 will bear against the support arm on the tightening machine, thereby preventing the test The sleeve 2 rotates; the head of the thrust rod bolt to be tested is installed on the inner side of the fixing nut sleeve 6 of the tightening machine, and is pressed on the protective gasket 5 at the same time, so as to avoid contact with the end surface of the test sleeve 2 or the test backing plate 4 Direct contact also prevents its surface from being abraded. The detection equipment can detect the elongation of the thrust rod bolt during the tightening process through the opening 3 on the test sleeve 2, and then obtain the bolt pretightening force. During the test, strain gauges are pasted on the bolts of the thrust rod, and the strain of the bolts can be detected by corresponding equipment.

The state after the test device of the present invention is normally assembled with the tested thrust rod bolt is like this. A protective gasket, a test backing plate, a test sleeve, another protective gasket and a test nut are sequentially worn on the bolt of the thrust rod to be tested. At the same time, a strain gauge is pasted on the bolt of the thrust rod, and the wire of the strain gauge is drawn out from the opening on the test sleeve, and the other end of the wire is connected to the strain gauge.

During the test: place one or more test backing plates (or not) at one end of the test sleeve, and the number of test backing plates is determined by the length difference between the tested thrust rod bolt and the test sleeve. The greater the length difference, the more pads, and vice versa. The reason is that the thread length at the end of the thrust rod bolt is limited. If the length difference between it and the test sleeve is too large, it will not be able to compress the nut installed between it and the bolt head when it is screwed to the end of the thread. Each part, the thrust rod bolt is not stressed like this. Only by selecting an appropriate number of test pads can the normal installation of the thrust rod bolts and nuts be ensured, and the thrust rod bolt heads and nuts can tighten the various parts installed on them, such as protective gaskets, test pads and test sleeves. At this moment, the thrust rod bolt is under stress.

The specific test process is as follows: Put the above-mentioned normally installed thrust rod bolts, test nuts and test device on the bolt tightening machine, and at the same time, the anti-rotation levers on both sides of the test device are pinned to the nut sleeve of the tightening machine. At the same time, the bolt head of the thrust rod is also set in the fixing nut sleeve of the tightening machine, and the test nut at the other end is set on the rotating shaft of the tightening machine.

After the tightening machine is started, the tightening machine rotates the test nut, but the thrust rod bolt will not rotate because it is sleeved on the fixing nut sleeve of the tightening machine. The relative movement between the bolt and the nut will compress the parts of the test device mounted on it. After each part is compressed, a reaction force will be generated. This force will react on the thrust rod bolt. It is detected by the strain gauge, from which the stress on the bolt can be calculated.

The stress on the part is equal to the strain (elongation of the strain gauge) multiplied by the elastic modulus of the material, which can be considered as a constant for the steel elastic modulus. (Using strain gauges to measure stress is a common method in the mechanical field, and the elastic modulus can also be easily found in mechanical design manuals or textbooks.)

The main purpose of the test device designed by the present invention is to measure the stress suffered by the thrust rod bolts when different tightening torques are applied. Too much stress will break the bolt; too little stress will cause the bolt to loosen during use. Through this experiment, we can clearly understand whether the tightening torque set by the tightening machine is appropriate.

To sum up, the thrust rod bolt testing device of the present invention can conveniently utilize the tightening equipment on the production line to carry out the tightening and pre-tightening force measurement tests of various specifications of the thrust rod bolts, and can adapt to different lengths of thrust by adjusting the number of test backing plates 4 Rod bolts, thereby improving the convenience and accuracy of experimental work.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (5)

1. A thrust rod bolt test device is characterized in that, comprising: test sleeve, test backing plate, two anti-rotation gear levers and retaining nut, The main body of the test sleeve is a cylinder, and an internal through hole is drilled in the center to pass through the thrust rod bolts. At both ends of the test sleeve, an ear protrudes to both sides, and on the ear There is a through hole, the anti-rotation lever is installed in the through hole of the ear, an opening above the test sleeve is connected with the internal through hole, and the wire of the strain gauge can pass through; The two anti-rotation gear rods are installed on the test sleeve through fixing nuts, which are in the shape of stepped shafts and are composed of two sections of cylinders with different diameters. The thinner section penetrates the ear holes on both sides of the test sleeve At the same time, its end is also designed with threads, which are installed on the test sleeve with fixing nuts; the thicker section is used to install the test backing plate, and the anti-rotation gear rod passes through both sides of the test backing plate through holes, and prevent the test device from rotating during the test; The test backing plate is installed on the two anti-rotation gear levers through the through holes on both sides. On the thick section of the two anti-rotation gear levers. 2. The thrust rod bolt test device according to claim 1, characterized in that, it also includes two protective gaskets, which are in the shape of a ring, respectively installed on both sides of the test sleeve or the test backing plate superior. 3 . The thrust rod bolt testing device according to claim 1 , wherein a plurality of test backing plates are installed on the anti-rotation gear lever. 4 . 4. The thrust rod bolt testing device according to claim 1, characterized in that, the anti-rotation lever is installed on both sides of the tightening machine fixing nut sleeve. 5. The thrust rod bolt testing device according to claim 1, characterized in that, the material of the test sleeve and the test backing plate is the same as that of the thrust rod.