CN206269985U - Machine Joint Surfaces normal stiffness test device - Google Patents

Abstract

The utility model discloses a testing device for the normal stiffness of a mechanical joint surface. The frame-shaped stand in the test device has a rectangular structure; the linear guide rail is arranged on the frame-shaped stand; the first test piece and the second test piece are slidably installed on the linear guide rail Above; the left frame and the right frame are provided with threaded holes for corresponding first bolts and second bolts to pass through; the first bolt is threaded with the threaded holes of the left frame, and the end passes through the left frame to connect to the left end of the first connecting shaft The second bolt is threadedly connected with the threaded hole of the right frame, and the end passes through the right frame to connect the right end of the second connecting shaft; the left end of the first test piece is provided with a first force sensor connected to the first connecting shaft, and the second test piece The right end of the piece is provided with a second force sensor connected to the second connecting shaft; the output ends of the first force sensor and the second force sensor are connected to the computer through the signal acquisition system. The device has a simple structure, is convenient to assemble and disassemble, and is easy to repeat the test, so that the normal stiffness of the mechanical joint surface can be better analyzed.

Description

Measuring device for normal stiffness of mechanical interface

technical field

The utility model belongs to the field of mechanical design and manufacture, in particular to a testing device for the normal stiffness of a mechanical joint surface.

Background technique

As an inherent structural form in the mechanical system, the mechanical joint surface has a significant impact on the overall dynamic performance of the mechanical system because it exhibits complex dynamic characteristics of both elasticity and damping under the action of an external load. Due to the contact stiffness and contact damping of the mechanical joint surface, there are many factors affecting the dynamic characteristics of the joint surface, and they are very complicated. These factors mainly include: the material of the joint surface, the processing method of the joint surface, the processing quality of the joint surface, and the joint surface. The conditions of the media, the size of the pre-tightening force of the joint surface, the nature and size of the dynamic load of the joint surface, the relative movement between the joint surfaces and other factors.

There are so many influencing factors, and their influencing laws are mostly non-linear, and the factors influence each other, so it is impossible to directly determine their influencing laws and degree of influence by means of theoretical analysis. Experimental research methods must be used to solve it.

In order to systematically study and ascertain the influence of the normal load on the mechanical joint surface on its normal stiffness, a complete set of testing devices is needed, but there is no relatively mature testing device in the prior art.

Utility model content

The purpose of the utility model is to provide a test device for the normal stiffness of a mechanical joint surface, so as to solve the above-mentioned technical problems. The utility model designs and fixes the joint interview piece, changes the stress state of the joint surface by adjusting the position of the bolt, and measures the normal stiffness of the mechanical joint surface by using multiple sets of basic experimental data and models.

In order to achieve the above object, the utility model has taken the following technical solutions:

A device for testing the normal stiffness of a mechanical joint, including: a first bolt, a first connecting shaft, a first force sensor, a first test piece, a second bolt, a second connecting shaft, a second force sensor, a second test piece, a straight line Guide rails, frame-shaped bench, signal acquisition system and computer; the frame-shaped bench has a rectangular structure, including left frame, right frame, upper frame and lower frame; linear guide rails are set on the frame-shaped bench; the first specimen and the second The second test piece is slidingly installed on the linear guide rail; the left frame and the right frame are provided with threaded holes for the corresponding first bolt and the second bolt to pass through; the first bolt is threaded with the threaded hole of the left frame, and the end passes through the left The frame is connected to the left end of the first connecting shaft; the second bolt is threadedly connected to the threaded hole of the right frame, and the end passes through the right frame to connect to the right end of the second connecting shaft; The right end of the first force sensor and the second test piece are provided with a second force sensor connected to the second connecting shaft; the output ends of the first force sensor and the second force sensor are connected to a computer through a signal acquisition system.

Further, it also includes a first thrust bearing, a first bearing seat, a second thrust bearing and a second bearing seat; the first connecting shaft is installed on the first bearing seat through the first thrust bearing, and the second connecting shaft passes through The second thrust bearing is installed on the second bearing seat; the first bearing seat and the second bearing seat are slidingly installed on the linear guide rail.

Further, the left end of the first test piece is provided with a groove, and the first force sensor is installed in the groove at the left end of the first test piece; the right end of the second test piece is provided with a groove, and the second force sensor is installed in the second test piece. into the groove at the right end of the piece.

Further, the linear guide rail includes an upper guide rail and a lower guide rail arranged in parallel, the upper guide rail is fixed on the upper frame, and the lower guide rail is fixed on the lower frame.

Further, the first test piece is in contact with the second test piece.

Further, interference fit between the first connecting shaft and the first thrust bearing; interference fit between the second connecting shaft and the second thrust bearing.

Further, the left end of the first connecting shaft is provided with an internally threaded hole, and the end of the first bolt is threadedly connected with the first connecting shaft through the internally threaded hole at the left end of the first connecting shaft; the right end of the second connecting shaft is provided with an internally threaded hole , the end of the second bolt is threadedly connected with the second connecting shaft through the internally threaded hole at the right end of the second connecting shaft.

Further, the axis centers of the first bolt, the first connecting shaft, the first force sensor, the first test piece, the second bolt, the second connecting shaft, the second force sensor and the second test piece are all located on the same straight line.

Further, the left frame and the right frame are arranged in parallel, the upper frame and the lower frame are arranged in parallel, the upper end of the left frame is vertically connected with the left end of the upper frame, the lower end of the left frame is vertically connected with the left end of the lower frame, and the upper end of the right frame is vertically connected with the right end of the upper frame Connection, the lower end of the right frame is vertically connected with the right end of the lower frame.

Further, the thrust bearing adopts a grease lubrication method, and the inner ring of the thrust bearing is positioned by a sleeve, and the outer ring is positioned by a bearing end cover.

Compared with the prior art, the utility model has the advantages of:

(1) It can be seen from the experimental device that there is only one variable in the whole experimental process, that is, the normal load, which is obtained by direct measurement with a force sensor, and then using the modeling method of the normal stiffness of the mechanical joint surface, the joint surface method can be accurately obtained. The effect of vertical load on its normal stiffness.

(2) In order to facilitate the research on the basic influencing factors affecting the normal stiffness of the joint surface, the experimental device has a simple structure, easy replacement, easy positioning, and can be used for repeated tests.

(3) The experimental device adopts the method of arranging the force sensors symmetrically on both sides, and the final experimental data takes the average value of the readings of the two force sensors, which reduces the measurement error.

(4) The experimental device is arranged with linear guide rails up and down. The first test piece, the second test piece, and the bearing housing can be directly slid in from both sides of the linear guide rail. The assembly is relatively easy, and the coaxiality between them can be guaranteed.

(5) In this experimental device, the connecting shaft is installed on the bearing seat through a thrust bearing. The thrust bearing can not only convert the radial force in the loading process into an axial force, but also ensure that the bolts, the connecting shaft, and the first specimen , the coaxiality between the second specimens.

Description of drawings

Fig. 1 is a schematic diagram of the device for testing the normal stiffness of the mechanical joint surface of the present invention.

Fig. 2 is a schematic diagram of the first test piece and the second test piece of the test device, wherein Fig. 2(a) is a front view, and Fig. 2(b) is a left side view.

detailed description

The following is a further detailed description of the mechanical joint surface normal stiffness testing device of the present invention in combination with the working principle and the structural drawings.

As shown in Figures 1 to 2, a device for testing the normal stiffness of a mechanical joint surface includes: a bolt 1, a connecting shaft 2, a thrust bearing 3, a bearing seat 4, a force sensor 5, a first test piece 6, a second Test piece 7, linear guide rail 8, frame-type bench 9, signal acquisition system and computer.

Due to the symmetrical arrangement of the measuring devices, for the convenience of explanation, the utility model patent only describes the working principle of the left device, and the principle of the right device is the same. The bolt 1 is connected to the left side of the connecting shaft 2, the connecting shaft 2 is installed on the bearing seat 4 through the thrust bearing 3, the right side of the connecting shaft is connected to the force sensor 5, the force sensor 5 is placed in the first test piece 6, and the frame-shaped table A vertically symmetrical linear guide rail 8 is arranged on the frame 9. The bearing housing 4 and the first test piece slide in from the left end of the linear guide rail 8. After installation, screw the bolts 1 on both sides to make the first test piece and the second test piece contact. The force sensor 5 is externally connected to a signal acquisition system, and transmits the normal load on the joint surface to the computer.

During the test, the connecting shaft 2 is first installed on the bearing housing 4 through the thrust bearing 3, and then both sides of the connecting shaft are respectively connected with bolts and force sensors. For the contact between the specimens, set the normal load of the joint surface as the only variable, apply multiple sets of normal loads to the joint surface sequentially through the bolts on both sides, and carry out the test of the normal stiffness of the mechanical joint surface, extract the experimental data during the experiment, and use The modeling method of the normal stiffness of the mechanical joint surface, from which the influence of the normal load on the joint surface on its normal stiffness is obtained.

Claims (9)

1. Machine Joint Surfaces normal stiffness test device, it is characterised in that including：First bolt, the first connecting shaft, the first power are passed Sensor, the first test specimen (6), the second bolt, the second connecting shaft, the second force snesor, the second test specimen (7), line slideway (8), frame Type stand (9), signal acquiring system and computer；

Frame-type stand is rectangular configuration, including left frame, left frame, upper side frame and lower frame；

Line slideway is arranged on frame-type stand；

First test specimen and the second test specimen are slidably mounted on line slideway；

Left frame, left frame are provided with the screwed hole passed through for the first bolt, the second bolt；The screw thread of the first bolt and left frame Hole is threadedly coupled, and end connects the left end of the first connecting shaft through left frame；Second bolt connects with the screwed hole screw thread of left frame Connect, end connects the right-hand member of the second connecting shaft through left frame；

The left end of the first test specimen is provided with the first force snesor of the first connecting shaft of connection, and the right-hand member of the second test specimen is provided with connection Second force snesor of the second connecting shaft；

The output end of the first force snesor and the second force snesor connects computer by signal acquiring system.

2. Machine Joint Surfaces normal stiffness test device according to claim 1, it is characterised in that also including the first thrust Bearing, first bearing seat, the second thrust bearing and second bearing seat；First connecting shaft is arranged on first by the first thrust bearing On bearing block, the second connecting shaft is arranged in second bearing seat by the second thrust bearing；First bearing seat and second bearing seat It is slidably mounted on line slideway.

3. Machine Joint Surfaces normal stiffness test device according to claim 1, it is characterised in that the left end of the first test specimen Groove is provided with, the first force snesor is installed in the groove of the first test specimen left end；The right-hand member of the second test specimen is provided with groove, the second power Sensor is installed in the groove of the second test specimen right-hand member.

4. Machine Joint Surfaces normal stiffness test device according to claim 1, it is characterised in that line slideway (8) is wrapped The upper rail and lower guideway be arrangeding in parallel are included, upper rail is fixed on upper frame, and lower guideway is fixed on underframe.

5. Machine Joint Surfaces normal stiffness test device according to claim 1, it is characterised in that the first test specimen and second Test specimen is contacted.

6. Machine Joint Surfaces normal stiffness test device according to claim 2, it is characterised in that the first connecting shaft and the Interference fit between one thrust bearing；Interference fit between second connecting shaft and the second thrust bearing.

7. Machine Joint Surfaces normal stiffness test device according to claim 2, it is characterised in that the first thrust bearing, Using the lubricating system of grease lubrication, inner ring is positioned second thrust bearing by sleeve, and outer ring is positioned by bearing (ball) cover.

8. Machine Joint Surfaces normal stiffness test device according to claim 1 a, it is characterised in that left side for the first connecting shaft End is provided with internal thread hole, and the end of the first bolt is connected axle thread with first and connects by the internal thread hole of the first connecting shaft left end Connect；The right-hand member of the second connecting shaft is provided with internal thread hole, the end of the second bolt by the internal thread hole of the second connecting shaft right-hand member with Second connecting shaft is threadedly coupled.

9. Machine Joint Surfaces normal stiffness test device according to claim 1, it is characterised in that the first bolt, first The axle center of connecting shaft, the first force snesor, the first test specimen, the second bolt, the second connecting shaft, the second force snesor and the second test specimen It is respectively positioned on same straight line.