CN114619140A

CN114619140A - Isolated motion

Info

Publication number: CN114619140A
Application number: CN202210347773.1A
Authority: CN
Inventors: 王玉林
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-04-01
Filing date: 2022-04-01
Publication date: 2022-06-14

Abstract

The invention discloses an isolated motion mechanism, which comprises the following preparation steps: (1) the method comprises the steps of changing the original mode of directly processing guide rails and rack mounting surfaces on an aluminum cross beam, adding strip steel on a main guide rail, a rack mounting surface and an auxiliary guide rail mounting surface, processing corresponding mounting surfaces on the strip steel, fastening the corresponding processed strip steel mounting surfaces on the aluminum cross beam by using a group of bolts, and processing the guide rails and the rack mounting surfaces on the strip steel respectively; (2) the bottom plates at two ends of the aluminum beam and the aluminum beam are integrated are removed, and are made into steel bottom plates, all functions of the original aluminum bottom plates are kept, and the corresponding connecting surfaces of the aluminum beam and the steel bottom plates are designed and fastened by bolts. Compared with the prior art, the invention has the advantages that: the adverse effect of the aluminum product on the cutting precision caused by the fact that the linear expansion coefficient of the aluminum product is far larger than that of steel is avoided, and the advantage of light weight of the aluminum beam is fully played.

Description

Isolated motion

Technical Field

The invention relates to the technical field of laser cutting machines, in particular to an isolated motion mechanism.

Background

The main structure of the laser cutting machine generally adopts a carbon steel welding lathe bed and a cast aluminum or aluminum profile welding beam. The carbon steel welding lathe bed well meets the requirements of rigidity and stability of the laser cutting machine; the aluminum beam has light weight and small inertia, and can well meet the requirements of high-speed cutting and quick steering. Therefore, the carbon steel welding bed body and the aluminum beam form the standard configuration of the laser cutting machine. However, the main structure of the steel and aluminum matching is not only advantageous, but also has obvious defects, and if the main structure is not properly processed, the cutting precision and the operation stability of the laser cutting machine are affected very adversely.

It is well known that almost all material dimensions change with temperature, i.e. expansion and contraction, and that steel and aluminium products are naturally no exception. The linear expansion coefficients of the steel and aluminum products changing along with the temperature have larger difference, and the reference can be found out: the linear expansion coefficient of the steel material is about 11 multiplied by 10 < -6 >/DEG C, and the linear expansion coefficient of the aluminum material is about 23 multiplied by 10 < -6 >/DEG C, which is close to twice of the linear expansion coefficient of the steel. The linear size expansion and contraction quantity of the steel product along with the temperature change is abbreviated as: 1 degree 1 silk 1 meter, the flexible volume of aluminium product then is: 1 meter 1 degree 2 silk. The relative expansion and contraction of the steel and aluminum products is about 1 meter and 1 degree and 1 wire. That is to say in same temperature variation range, the flexible volume of aluminium product is the twice of steel product, and when ambient temperature changed, steel, aluminium fitting piece can produce relative displacement because of actual flexible volume difference, and the displacement appears and can produce adverse effect to work precision and security in the key position.

The beam is the main moving part of the cutting machine. The crossbeam main part is the aluminum alloy material, and the guide rail and the rack of installation are the steel on the crossbeam. The beam length is usually more than 2 meters, the guide rail is slightly shorter than the beam, the racks are spliced, and the standard length of each common rack is 1 meter. As mentioned above, there is a significant difference in the expansion and contraction rate of steel and aluminum products when the temperature changes. The day and night temperature difference is above 10 ℃, the relative stretching amount generated by the guide rail and the cross beam on the whole length range of the cross beam reaches 20 threads, and the relative stretching amount generated by each rack also has 10 threads. In the early stage, because the guide rail and the rack are tightly fastened on the cross beam by bolts, the relative expansion amount does not completely generate actual relative displacement, and only alternating stress exists. However, the fastening bolt is repeatedly subjected to interaction forces in two directions due to the alternation of day and night for a long time, so that the bolt is inevitably loosened, and finally the guide rail and the rack are displaced, thereby bringing adverse effects to the operation precision. After the rack fastening bolt is loosened, the relative expansion amount of the rack can be intensively reflected at the butt joint of the rack, the day and night temperature difference can cause the variation of more than 10 threads of the rack butt joint gap, and the extreme temperature difference of cold and hot is more than 40 ℃, so that the variation of the rack butt joint gap of more than 40 threads can be caused, which is enough to cause serious influence on the positioning precision and the operation stability of an X axis.

The beam is not only matched with the guide rail and the rack of the beam, but also matched with the linear guide rails and the racks arranged on two sides of the lathe bed to complete Y-axis movement through the driving motor. When the ambient temperature changes, the aluminum beam and the welding lathe bed have the same expansion difference, the span size is larger, and the relative expansion amount caused by the temperature change is also larger. The relative expansion and contraction caused by the temperature difference between day and night can cause loosening of fastening bolts at the relevant parts and deviation of fixing positions of fixing parts; extreme temperature differences in chills and hot weather can cause a shift in the fixed position of the limit. The span of the Y-axis driving motors at two ends of the beam is generally more than 2 meters, the generated limit relative expansion amount can reach more than 80 wires, 40 wires of displacement can be generated when the Y-axis driving motors are equally divided to the ends (almost impossible to equally divide in practical situations), the Y-axis positioning precision can be seriously reduced corresponding to 40 wires of gear/rack meshing gaps, impact is generated when the Y-axis is reversed at high speed due to the fact that the Y-axis driving motors exceed 40 wires of meshing gaps, and the service life of the gear and the rack is seriously shortened.

Therefore, the relative expansion and contraction caused by frequent day and night temperature difference can cause the fastening bolt at the joint of the steel and the aluminum to gradually loosen; the temperature difference along with seasonal variation can cause obvious relative displacement of steel and aluminum matching pieces, and when the displacement is accumulated to a certain degree, the displacement is enough to bring non-negligible influence on the working precision of equipment, and even has potential safety hazard.

In general, the adverse effect of the difference in linear expansion coefficients of steel and aluminum on the accuracy of the laser cutting machine is gradually increased, because the ambient temperature is also changed slowly with the change of seasons. However, when the difference between the production place of the device and the latitude degree of the user is large and the difference between the climate temperature is large, the relative expansion and contraction amount caused by the temperature difference between the device and the user in the field environment can bring a remarkable influence on the cutting precision and even influence the normal operation of the device. In addition, the longer the beam is made, the greater the relative amount of expansion and contraction is, and the greater the adverse effect on the accuracy is.

Disclosure of Invention

The invention aims to overcome the technical defects, provides an isolated motion mechanism, avoids the adverse effect on the cutting precision caused by the fact that the linear expansion coefficient of an aluminum product is far larger than that of steel, and simultaneously gives full play to the advantage of light weight of an aluminum beam.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: an isolated motion mechanism comprises the following preparation steps: (1) the method comprises the steps of changing the original mode of directly processing guide rails and rack mounting surfaces on an aluminum cross beam, adding strip steel on a main guide rail, a rack mounting surface and an auxiliary guide rail mounting surface, processing corresponding mounting surfaces on the strip steel, fastening the corresponding processed strip steel mounting surfaces on the aluminum cross beam by a group of bolts, and processing the main guide rail and the rack mounting surfaces on the strip steel respectively;

(2) the bottom plates at two ends of the aluminum beam and the aluminum beam are integrated are removed, and are made into steel bottom plates, all functions of the original aluminum bottom plates are kept, and the corresponding connecting surfaces of the aluminum beam and the steel bottom plates are designed and fastened by bolts.

Further, the specific preparation steps of the step (1) are as follows:

firstly, processing an installation surface on an aluminum cross beam into a shallow groove with the depth of about 3mm, wherein the width is determined according to actual needs and is matched with the width of strip steel, clearance fit is adopted in the matching, the tolerance is not lower than H8/H8, the matching surface of the aluminum cross beam and the strip steel is subjected to finish machining, the roughness is not less than 3.2, the installation precision is ensured, and the transverse displacement in operation is reduced;

the main guide rail and the rack on the strip steel are fastened on the aluminum cross beam by bolts and then are processed so as to ensure the overall assembly precision, and in order to reduce the processing deformation and the processing stress, the strip steel is roughly processed before being installed and enough finishing allowance is reserved;

the auxiliary guide rail has less influence on the processing precision, when the aluminum cross beam is short in length and does not need to be spliced with the guide rail, strip steel can be omitted, the original structure is kept, when the aluminum cross beam is long and the guide rail needs to be spliced, the strip steel structure needs to be increased, otherwise, the relative expansion amount can cause the increase of a gap at the butt joint part, and the operation stability and the service life of the guide rail are reduced.

Further, the specific preparation steps of the step (2) are as follows:

firstly, the connecting surface of the steel bottom plate and the aluminum cross beam is designed into a shallow groove, the width of the shallow groove is matched with that of the aluminum cross beam, clearance fit is adopted, the matching tolerance is not lower than H8/H8, and the aluminum cross beam is prevented from shifting back and forth on the steel bottom plate in the operation process;

finish machining is carried out on the connecting surface of the aluminum beam and the steel bottom plate, the roughness is not less than 3.2, and the requirement of geometric tolerance required by assembly is guaranteed;

and thirdly, the steel base plate is used as an independent part and processed to the required precision without being connected with the aluminum cross beam and then processed, the steel base plate is firstly assembled on the guide rail sliding block of the lathe bed during equipment assembly, and the aluminum cross beam is then assembled on the steel base plate and fastened by bolts.

Furthermore, the main guide rail is a guide rail close to the rack, and the main guide rail and the rack are made of the same strip steel, namely the main guide rail and the rack are respectively processed on the same strip steel, so that the relative position of the main guide rail and the rack can be prevented from changing, and the cutting precision can be kept.

Compared with the prior art, the invention has the advantages that: the invention separates the relative expansion amount generated by the different linear expansion coefficients of the aluminum product and the steel product when the environmental temperature changes from the key component of the laser cutting machine through an additional structure, so that when the temperature changes, the relative expansion amount still exists, but the cutting precision and the safety are not influenced, the adverse influence on the cutting precision caused by the fact that the linear expansion coefficient of the aluminum product is far larger than that of the steel product is avoided, and the advantage of light weight of the aluminum beam is fully exerted.

Drawings

Fig. 1 is a schematic structural view of an aluminum cross beam of the present invention.

Fig. 2 is a schematic structural view of the machine bed of the present invention.

As shown in the figure: 1. the device comprises an aluminum beam, 2, a lathe bed, 3, a steel bottom plate, 4, first mounting surfaces, 5, second mounting surfaces, 6 and guide rails.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

As shown in fig. 1-2, an isolated motion mechanism comprises the following preparation steps: (1) the method comprises the steps of changing the original mode of directly processing guide rails and rack mounting surfaces on an aluminum cross beam, adding strip steel on a main guide rail, a rack mounting surface and an auxiliary guide rail mounting surface, processing corresponding mounting surfaces on the strip steel, fastening the corresponding processed strip steel mounting surfaces on the aluminum cross beam by a group of bolts, and processing the main guide rail and the rack mounting surfaces on the strip steel respectively; the concrete requirements are as follows: firstly, processing an installation surface on an aluminum cross beam into a shallow groove with the depth of about 3mm, wherein the width is determined according to actual needs and is matched with the width of strip steel, clearance fit is adopted in the matching, the tolerance is not lower than H8/H8, the matching surface of the aluminum cross beam and the strip steel is subjected to finish machining, the roughness is not less than 3.2, the installation precision is ensured, and the transverse displacement in operation is reduced;

(2) Removing the bottom plates at two ends of the aluminum beam and integrating the aluminum beam with the aluminum beam, manufacturing a steel bottom plate, keeping all functions of the original aluminum bottom plate, designing corresponding connecting surfaces on the aluminum beam and the steel bottom plate respectively, and connecting and fastening by using bolts; the concrete requirements are as follows: firstly, the connecting surface of the steel bottom plate and the aluminum cross beam is designed into a shallow groove, the width of the shallow groove is matched with that of the aluminum cross beam, clearance fit is adopted, the matching tolerance is not lower than H8/H8, and the aluminum cross beam is prevented from shifting back and forth on the steel bottom plate in the operation process;

the steel bottom plate is used as an independent part, the required precision is achieved through processing, the steel bottom plate does not need to be connected with the aluminum cross beam and then processed, the steel bottom plate is assembled on the guide rail sliding block of the lathe bed during equipment assembly, and the aluminum cross beam is assembled on the steel bottom plate and fastened through bolts.

The present invention and its embodiments have been described above, and the description is not intended to be limiting, and the drawings are only one embodiment of the present invention, and the actual structure is not limited thereto. In summary, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. An isolated motion mechanism, characterized in that: the preparation method comprises the following preparation steps: (1) the method comprises the steps of changing the original mode of directly processing guide rails and rack mounting surfaces on an aluminum cross beam, adding strip steel on a main guide rail, a rack mounting surface and an auxiliary guide rail mounting surface, processing corresponding mounting surfaces on the strip steel, fastening the corresponding processed strip steel mounting surfaces on the aluminum cross beam by a group of bolts, and processing the main guide rail and the rack mounting surfaces on the same strip steel respectively;

2. An isolated motion mechanism according to claim 1, wherein: the specific preparation steps of the step (1) are as follows:

firstly, processing an installation surface on an aluminum cross beam into a shallow groove with the depth of 3mm, wherein the width is determined according to actual needs and is matched with the width of strip steel, clearance fit is adopted in the matching, the tolerance is not lower than H8/H8, the matching surface of the aluminum cross beam and the strip steel is subjected to finish machining, the roughness is not less than 3.2, the installation precision is ensured, and the transverse displacement in operation is reduced;

3. An isolated motion mechanism according to claim 1, wherein: the specific preparation steps of the step (2) are as follows: