CN204114042U - A kind of two-freedom-degree parallel mechanism - Google Patents

Abstract

A two-degree-of-freedom parallel mechanism, which includes an operating platform, a driving motor, a guide rail, a guide sleeve, a slider, and a timing belt; a reversing bushing is installed on each of the two moving sliders, and the reversing bushing is The upper and lower guide sleeve structure; the operation platform is equipped with a drive shaft sleeve on both sides of the Y direction corresponding to the other end of the pulley; the timing belts are respectively connected to the two ends of the working slider, and each timing belt is reversed from one end of the working slider in turn. The shaft sleeve, pulley, transmission shaft sleeve, drive shaft sleeve on the opposite side, and reversing sleeve on the opposite side are bypassed, and then fixed on the other end of the working slider; the first synchronous belt and the second synchronous belt are installed on different level. The existing two reversing sleeves are replaced by a single reversing sleeve with upper and lower guide sleeve structures, which improves the layout of the synchronous belt in the parallel mechanism and greatly improves the working space of the XY transmission platform. share.

Description

A two-degree-of-freedom parallel mechanism

technical field

The utility model relates to a mechanical transmission structure, in particular to a two-degree-of-freedom parallel mechanism.

Background technique

In China, the research on parallel mechanism with few degrees of freedom has a history of 20 years, but the progress is very slow. Compared with the series mechanism, the parallel mechanism has many advantages such as low motion inertia, high stiffness, high dexterity, small size and high power-to-weight ratio. The two-degree-of-freedom parallel mechanism can be applied to 3D printers, CNC machine tools, laser cutting machines and other fields.

With the development of science and technology, and people's requirements for the precision and space occupancy of the mechanism are getting higher and higher, which is especially important for the optimization of the parallel mechanism. For example, the 3D printer MARK34 from a company in the Netherlands in 2013 uses the dynamic principle of the H-Bot mechanism on its plane, which is characterized by simple structure, high precision and fast speed, but the H-Bot mechanism is driven by a single synchronous belt. Its rotation error is large. Later, someone improved the H-Bot mechanism and named it the improved Core-XY mechanism, which improved the rotation error caused by the reverse movement of the H-Bot mechanism, but brought about the problem of low space utilization.

Contents of the invention

In order to solve the problems of the rotation error of the working slider in the existing two-degree-of-freedom parallel mechanism, the rigidity of the large-scale mechanism is not large, and the space occupancy rate is not high, a two-degree-of-freedom parallel mechanism is provided. The driving force is large, the speed is high, and the rotation error is small.

In order to solve the above problems, the utility model adopts the following technical solutions:

A two-degree-of-freedom parallel mechanism, which includes an operating platform, a driving motor, a guide rail, a guide sleeve, a slider, and a timing belt;

The drive motor is installed on both sides of the operation platform, and the output end of the drive motor is installed with pulleys; two Y guide rails are installed on both sides of the operation platform, and each of the two Y guide rails is equipped with a moving slider and two moving sliders. X-guiding rails are installed between them, and the working slider is installed on the X-guiding rails;

A reversing sleeve is installed on each of the two moving sliders, and the reversing sleeve is a two-layer guide sleeve structure; the operating platform is equipped with a transmission sleeve at the other end corresponding to the pulley in the Y direction on both sides;

The first synchronous belt is connected to both ends of the working slider. The first synchronous belt starts from one end of the working slider in turn from the lower guide bush of the reversing bushing on this side, the first pulley on the same side, and the transmission bushing on the same side. , The lower guide sleeve of the transmission bushing on the opposite side and the reversing bushing on the opposite side is bypassed, and then fixed on the other end of the working slider;

The second synchronous belt is connected to both ends of the working slider, and the second synchronous belt starts from one end of the working slider in turn from the upper guide bush of the reversing bushing on this side, the first pulley on the same side, and the transmission bushing on the same side. , The upper guide sleeve of the transmission bushing on the opposite side and the reversing bushing on the opposite side is bypassed, and then fixed on the other end of the working slider;

The first synchronous belt and the second synchronous belt are installed on different horizontal planes.

In the above-mentioned two-degree-of-freedom parallel mechanism, the operating platform is equipped with two transmission bushings at the other ends of the Y guide rails on both sides corresponding to the pulleys;

The first synchronous belt is connected to both ends of the working slider. The first synchronous belt starts from one end of the working slider in turn from the lower guide bush of the reversing bushing on this side, the first pulley on the same side, and the transmission bushing on the same side. The lower guide sleeve of the lower guide sleeve, the lower guide sleeve of the transmission bushing on the opposite side, and the lower guide sleeve of the reversing bushing on the opposite side are bypassed, and then fixed on the other end of the working slider;

The second synchronous belt is connected to both ends of the working slider, and the second synchronous belt starts from one end of the working slider in turn from the upper guide bush of the reversing bushing on this side, the first pulley on the same side, and the transmission bushing on the same side. The upper guide sleeve of the upper guide sleeve, the upper guide sleeve of the drive shaft sleeve on the opposite side, and the upper guide sleeve of the reversing sleeve on the opposite side are bypassed, and then fixed on the other end of the working slider.

In the above-mentioned two-degree-of-freedom parallel mechanism, the operating platform is equipped with a transmission bush at the other end of the Y guide rail on both sides corresponding to the pulley, and the two transmission bushes are two-layer guide bush structure;

The first synchronous belt is connected to both ends of the working slider. The first synchronous belt starts from one end of the working slider in turn from the lower guide bush of the reversing bushing on this side, the first pulley on the same side, and the transmission bushing on the same side. The lower guide sleeve of the lower guide sleeve, the lower guide sleeve of the transmission bushing on the opposite side, and the lower guide sleeve of the reversing bushing on the opposite side are bypassed, and then fixed on the other end of the working slider;

The second synchronous belt is connected to both ends of the working slider, and the second synchronous belt starts from one end of the working slider in turn from the upper guide bush of the reversing bushing on this side, the first pulley on the same side, and the transmission bushing on the same side. The upper guide sleeve of the upper guide sleeve, the upper guide sleeve of the drive shaft sleeve on the opposite side, and the upper guide sleeve of the reversing sleeve on the opposite side are bypassed, and then fixed on the other end of the working slider.

The above-mentioned two-degree-of-freedom parallel mechanism is characterized in that the operating platform is processed from a whole plate.

In the aforementioned two-degree-of-freedom parallel mechanism, the plate is made of aluminum.

The two driving motors each drive a synchronous belt and control the working slider at the same time, which solves the rotation error caused by a synchronous belt driving the working slider in the previous parallel mechanism, and improves the driving force and stability of the mechanism.

The workbench is processed with a whole piece of aluminum alloy material, which improves the rigidity of the mechanism and reduces the noise of the mechanism at the same cost. The workbench is made of aluminum alloy material, which reduces the noise during the movement of the mechanism, improves the rigidity of the mechanism, and greatly improves the heat dissipation of the drive motor, which is conducive to the long-term stable operation of the mechanism.

A single reversing bushing with an upper and lower guide sleeve structure replaces the existing two reversing bushings, which improves the layout of the synchronous belt in the parallel mechanism and greatly improves the working space of the X-Y transmission platform. occupancy rate.

Compared with the improved Core-XY mechanism, the two drive bushes on the same side can be combined into one drive bush with upper and lower guide bush structures, which can also increase the space occupation.

Attached Figure 1 is the schematic diagram of the H-Bot mechanism. It can be seen from the figure that the H-Bot mechanism is a parallel mechanism, and the X and Y axis movements require two motors to move synchronously to ensure the normal operation of the mechanism. This mechanism solves the problems of lack of driving ability, low speed, large size of the mechanism, and difficulty in realizing small-angle routes in the previous planar series mechanism. rotation error.

Attached Figure 2 is the schematic diagram of the improved Core-XY mechanism. It can be seen from the figure that the mechanism has made corresponding improvements on the basis of the H-Bot mechanism, and the layout of the timing belt has been improved while the kinematics mapping remains unchanged. A synchronous belt is connected by a single motor respectively, and the two synchronous belts are divided into upper and lower layers, and control the moving slider at the same time. In this way, the rotation error of the mechanism is improved, but it brings about the problem that the working space occupation rate is not large.

We set the synchronous pulley and the radius of the bearing sleeve as r; we calculate the space utilization rate of the XY plane of the Core-XY mechanism according to the following steps:

As shown in Figure 2, the XY plane area of the workbench is:

S1=(ω ₁ +2r _)* (h ₁ +2r ₎

In the formula, ω ₁ is the distance between the two outer drive shaft sleeves, h ₁ is the distance from the outer drive shaft to the pulley,

The effective area of the workbench is:

S11=(ω ₂ -2r-ω _1)* (h ₁ -2r-d1-h3 ₎

In the formula, ω ₂ is the distance between the two inner drive bushings, h ₃ is the height of the working slider,

Among them, d1 is the distance between the center of the bottom shaft sleeve in the Y direction,

In the end, the space utilization rate of the XY plane of the Core-XY mechanism workbench is:

Q1= S11/ S1

Fig. 3 is the schematic diagram of the utility model A-Bot. It can be seen from the figure that one side of the reversing bushing in the X-axis direction of the mechanism is reduced, and the layout of the limit bearing at the bottom is slightly adjusted. Since the assembly configuration of the modified transmission mechanism is similar to the letter "A", it is called the A-Bot mechanism.

We make the synchronous pulley and the shaft sleeve radius r; we calculate the space utilization rate of the XY plane of the A-Bot mechanism of the utility model according to the following calculation steps:

As shown in Figure 3, the XY plane area of the workbench is:

S2=(ω ₁ +2r _)* (h ₁ +2r ₎

The effective area of the workbench is:

S21=(ω ₂ -2r-ω _{3 )*} (h ₁ -2r-d2-h3 ₎

Where d2 is the distance between the centers of the bottom bushing in the Y direction.

Finally, the space utilization rate of the XY plane of the A-Bot mechanism workbench of the utility model is:

Q2= S21/ S2

Assuming that the improved Core-XY mechanism and the utility model A-Bot mechanism have the same external dimensions of the workbench, and the dimensions of each bushing and synchronous pulley, it can be seen that the difference lies in the distance in the Y direction of the working platform. In the new X direction, one reversing bushing replaces the original two reversing bushings, so the utility model is at least 2 r shorter than the Core-XY mechanism. Therefore, our space usage Q2 is larger.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described.

Figure 1 is a schematic diagram of the H-Bot mechanism.

Figure 2 is a schematic diagram of the improved Core-XY mechanism.

Fig. 3 is a schematic diagram of the A-Bot mechanism of the utility model.

Fig. 4 is a structural schematic diagram of Embodiment 1 of the utility model.

Fig. 5 is a schematic structural diagram of Embodiment 2 of the present invention.

The marks in the figure are: 21, 22 synchronous pulley, 31, 32 synchronous belt, 41, 46 reversing bushing, 42, 43, 44, 45 transmission bushing, 423, 445 transmission bushing, 51, 52 moving slider , 53 working sliders, 61, 61Y guide rails, 63, 64X guide rails, 71, 72 motors.

Detailed ways

Embodiment one

Referring to the accompanying drawings, a two-degree-of-freedom parallel mechanism includes an operating platform, a drive motor, guide rails, bushings, sliders, and timing belts; the operating platform is processed from a single piece of aluminum plate;

Drive motor 71,72 is installed on both sides of the operation platform, and the output end of the drive motor is equipped with synchronous pulley 21,22; Two Y guide rails 61,62 are installed on both sides of the operation platform, and a Only move the sliders 51, 52, X-guiding rails 63, 64 are installed between the two moving sliders, and the working slider 53 is installed on the X-guiding rails;

A reversing shaft sleeve 41, 46 is respectively installed on the two moving sliders 51, 52, and the reversing shaft sleeve is a two-layer guide sleeve structure; Drive shaft sleeves 42, 43 and 44, 45;

The first synchronous belt 31 is connected to the two ends of the working slider 53, and the first synchronous belt starts from the right end of the working slider successively from the lower guide sleeve of the reversing bushing 41 on this side, the first pulley 21 on the same side, and the first pulley 21 on the same side. The transmission shaft sleeve 43, the transmission shaft sleeve 44 on the opposite side, and the lower guide sleeve of the reversing shaft sleeve 46 on the opposite side are bypassed, and then fixed on the other end of the working slider;

The second synchronous belt 32 is connected to the two ends of the working slider, and the second synchronous belt starts from the left end of the working slider successively from the upper guide sleeve of the reversing shaft sleeve 46 on this side, the first pulley 22 on the same side, and the first pulley 22 on the same side. The transmission shaft sleeve 45, the transmission shaft sleeve 42 on the opposite side, and the upper guide sleeve of the reversing shaft sleeve 41 on the opposite side are bypassed, and then fixed on the other end of the working slider; the first synchronous belt and the second synchronous belt are installed on different level.

Embodiment two

The difference from Embodiment 1 is that in this embodiment, the two drive bushes on the same side in the Y direction are combined into a single drive bush 423, 445 with upper and lower guide bush structures;

The first synchronous belt 31 is connected to the two ends of the working slider 53, and the first synchronous belt starts from the right end of the working slider successively from the lower guide sleeve of the reversing bushing 41 on this side, the first pulley 21 on the same side, and the first pulley 21 on the same side. The lower guide sleeve of the drive shaft sleeve 423, the lower guide sleeve of the drive shaft sleeve 445 on the opposite side, and the lower guide sleeve of the reversing sleeve 46 on the opposite side are bypassed, and then fixed on the other end of the working slider;

The second synchronous belt 32 is connected to both ends of the working slider 53, and the second synchronous belt starts from the left end of the working slider successively from the upper guide sleeve of the reversing bushing 46 on this side, the first pulley 22 on the same side, and the same side. The upper-level guide sleeve of the drive shaft sleeve 445, the upper-level guide sleeve of the transmission shaft sleeve 423 of the different side, and the upper-level guide sleeve of the reversing shaft sleeve 41 of the different side are bypassed, and then fixed on the other end of the working slide block.

Claims (5)

1. a two-freedom-degree parallel mechanism, this mechanism comprises operating platform, drive motor, guide rail, guide pin bushing, slide block, and Timing Belt, it is characterized in that:

Drive motor is arranged on operating platform both sides, and drive motor output terminal is provided with belt wheel; Two Y-direction guide rails assemblings, in operating platform both sides, two Y-direction guide rails are respectively provided with a moving slider, are provided with X direction guiding rail between two moving sliders, and work slide block is arranged on X direction guiding rail;

Two moving sliders are respectively provided with a commutation axle sleeve, and commutation axle sleeve is upper and lower two-layer guide sleeve structure; The other end that operating platform corresponds to belt wheel in both sides Y-direction is provided with driving sleeve;

First Timing Belt is connected to work slide block two ends, first Timing Belt is walked around from lower floor's guide pin bushing of the commutation axle sleeve of the driving sleeve of the driving sleeve of the first belt wheel of lower floor's guide pin bushing of the commutation axle sleeve of this side, homonymy, homonymy, heteropleural, heteropleural successively from work slide block one end, then is fixed on the other end of work slide block;

Second Timing Belt is connected to work slide block two ends, second Timing Belt is walked around from the upper strata guide pin bushing of the commutation axle sleeve of the driving sleeve of the driving sleeve of the first belt wheel of the upper strata guide pin bushing of the commutation axle sleeve of this side, homonymy, homonymy, heteropleural, heteropleural successively from work slide block one end, then is fixed on the other end of work slide block;

First Timing Belt is installed on different horizontal planes from the second Timing Belt.

2. a kind of two-freedom-degree parallel mechanism as claimed in claim 1, is characterized in that: the other end that operating platform corresponds to belt wheel at both sides Y-direction guide rail is separately installed with two driving sleeves;

First Timing Belt is connected to work slide block two ends, first Timing Belt is walked around from lower floor's guide pin bushing of the commutation axle sleeve of lower floor's guide pin bushing of the driving sleeve of lower floor's guide pin bushing of the driving sleeve of the first belt wheel of lower floor's guide pin bushing of the commutation axle sleeve of this side, homonymy, homonymy, heteropleural, heteropleural successively from work slide block one end, then is fixed on the other end of work slide block;

Second Timing Belt is connected to work slide block two ends, second Timing Belt is walked around from the upper strata guide pin bushing of the commutation axle sleeve of the upper strata guide pin bushing of the driving sleeve of the upper strata guide pin bushing of the driving sleeve of the first belt wheel of the upper strata guide pin bushing of the commutation axle sleeve of this side, homonymy, homonymy, heteropleural, heteropleural successively from work slide block one end, then is fixed on the other end of work slide block.

3. a kind of two-freedom-degree parallel mechanism as claimed in claim 1, is characterized in that: the other end that operating platform corresponds to belt wheel at both sides Y-direction guide rail is separately installed with a driving sleeve, and these two driving sleeves are upper and lower two-layer guide sleeve structure;

First Timing Belt is connected to work slide block two ends, first Timing Belt is walked around from lower floor's guide pin bushing of the commutation axle sleeve of lower floor's guide pin bushing of the driving sleeve of lower floor's guide pin bushing of the driving sleeve of the first belt wheel of lower floor's guide pin bushing of the commutation axle sleeve of this side, homonymy, homonymy, heteropleural, heteropleural successively from work slide block one end, then is fixed on the other end of work slide block;

Second Timing Belt is connected to work slide block two ends, second Timing Belt is walked around from the upper strata guide pin bushing of the commutation axle sleeve of the upper strata guide pin bushing of the driving sleeve of the upper strata guide pin bushing of the driving sleeve of the first belt wheel of the upper strata guide pin bushing of the commutation axle sleeve of this side, homonymy, homonymy, heteropleural, heteropleural successively from work slide block one end, then is fixed on the other end of work slide block.

4. a kind of two-freedom-degree parallel mechanism as claimed in claim 1, is characterized in that operating platform is processed by monoblock sheet material.

5. a kind of two-freedom-degree parallel mechanism as claimed in claim 4, is characterized in that described sheet material is aluminum material.