A backlash-free stepless pitch-changing mechanism

Abstract

The present invention belongs to the technical field of spacing adjustment, and specifically relates to a backlash-free stepless pitch-changing mechanism, including a base plate, a power plate, a power mechanism and a pitch-changing module; the power plate is provided with n mutually parallel first guide rails, and the base plate is provided with a second guide rail; the pitch-changing module includes: n inclined wedge blocks, fixed workstations, movable workstations slidably connected to different first guide rails, and a tensioning block, respectively, and the tensioning block is attracted to the output magnetic ring in the magnetic coupling cylinder; the front end of the inclined wedge block has a pitch-changing inclined surface, the front end of the inclined wedge block is located between two adjacent workstations, and the lower side of the nth inclined wedge block has a receiving cavity capable of accommodating the n-1th inclined wedge block. The present invention drives the inclined wedge block to press the workstations on both sides through the power mechanism, and the magnetic coupling cylinder squeezes the workstations toward the middle, and there is no backlash, so as to ensure the smooth and stepless adjustment of the spacing between the workstations, and the pitch-changing adjustment has high precision, which can meet the stepless pitch-changing requirements in high-precision occasions.

Description

Technical Field

[0001] The invention belongs to the technical field of spacing adjustment, and in particular relates to a backlash-free stepless spacing mechanism. Background Art

[0002] In the industrial field, the distance between different workstations is usually adjusted. Traditional distance variable mechanisms are generally divided into: fixed-distance distance variable mechanism, stepped distance variable mechanism and stepless distance variable mechanism. The fixed-distance distance variable mechanism can only adjust the distance of one distance; the stepped distance variable mechanism can adjust the distance of multiple discrete data distances, and the stepless distance variable mechanism can continuously adjust the distance between workstations.

[0003] The stepless pitch-changing mechanism can achieve any distance within the pitch-changing range. Figure 1 The guide groove type stepless pitch changing mechanism shown is achieved by setting a plurality of guide grooves 12 which converge and tilt toward the middle on the guide plate 11, and the guide rod 13 fixed on the slider moves in the guide groove 12. The guide plate 11 is driven to move by the screw nut pair 42 to adjust the distance between the sliders. In order to ensure smooth pitch change, there is a gap between the slider and the guide groove 12. When the mechanism changes direction, backlash will be generated, resulting in shaking and jittering, and the stepless pitch changing accuracy is low.

[0004] Likewise Figure 2 In the shear frame 21 type stepless distance variable mechanism shown, the workstation is fixed at the intersection of the two connecting rods 22 of the shear frame 21 by a connecting rod 22, and the stepless distance variable between the workstations is achieved by pulling or compressing the shear frame 21; there is still a gap between the connecting rod 22 and the connecting rod 22 pin, which will cause backlash, resulting in low precision and cumulative errors.

[0005] The above two stepless pitch-changing mechanisms cannot meet the stepless pitch-changing requirements in high-precision occasions. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the prior art that the stepless pitch change is prone to backlash, shaking, jittering and low precision, and to provide a backlash-free stepless pitch change mechanism that can meet the needs of high-precision occasions.

[0007] The technical solution adopted by the present invention to solve its technical problem is:

[0008] A backlash-free stepless pitch-changing mechanism, characterized in that it comprises a base plate, a power plate slidably connected to the base plate, a power mechanism for pushing the power plate to move, and a pitch-changing module; the power plate is provided with n first guide rails arranged parallel to each other, and the base plate is provided with second guide rails parallel to the first guide rails; the pitch-changing module comprises: n inclined wedge blocks slidably connected to different first guide rails, respectively, a fixed station fixed to the base plate, n movable stations slidably connected to the second guide rails, and a tensioning block slidably connected to the second guide rails and resting against the outer side surface of the outermost movable station, the tensioning block being attracted to the output magnetic ring in the magnetic coupling cylinder; the front end of the inclined wedge block has a pitch-changing inclined surface in contact with the station, the front end of the inclined wedge block is pressed between two adjacent stations, and the lower side of the nth inclined wedge block has a accommodating cavity that can accommodate the n-1th inclined wedge block.

[0009] Furthermore, the power mechanism includes: a servo motor mounted on the base plate and a lead screw nut pair connected to an output end of the servo motor, and a nut of the lead screw nut pair is connected to the power plate.

[0010] Furthermore, the power mechanism is a hydraulic cylinder, and the output end of the hydraulic cylinder is connected to the power plate.

[0011] Furthermore, the bottom plate has a third guide rail vertically arranged with respect to the first guide rail, and the power plate is slidably connected to the third guide rail.

[0012] Furthermore, the second guide rails are two arranged in parallel, and adjacent movable workstations are slidably connected to different second guide rails respectively.

[0013] Furthermore, two variable pitch modules are arranged on the power plate, and the two variable pitch modules share a fixed station in the middle.

[0014] Furthermore, the pitch-changing module has four inclined wedges, wherein the fourth inclined wedge of one pitch-changing module abuts against the middle fixed station, and the first inclined wedge of another pitch-changing module abuts against the middle fixed station.

[0015] Furthermore, the inclined wedge block is bilaterally symmetrically provided with variable pitch inclined surfaces.

[0016] Furthermore, a variable pitch inclined surface is provided on one side of the inclined wedge block.

[0017] Furthermore, the inclination angles of the variable pitch inclined surfaces of the plurality of inclined wedge blocks are the same.

[0018] The beneficial effects of the backlash-free stepless pitch-changing mechanism of the present invention are:

[0019] 1. By pushing the power plate to drive the variable pitch inclined surface at the front end of the inclined wedge block to extend into different depths between two adjacent workstations, the distance between the workstations can be adjusted steplessly. At the same time, by adjusting the air pressure of the magnetic coupling cylinder, the tensioning block is guaranteed to press the movable workstation with constant force. The power mechanism drives the inclined wedge block to press the workstation on both sides, while the magnetic coupling cylinder squeezes the workstation toward the middle. There is no backlash, ensuring a smooth and stepless adjustment of the spacing between the workstations. The variable pitch adjustment has high precision and can meet the stepless variable pitch requirements in high-precision occasions.

[0020] 2. By changing the inclination angle of the pitch-changing inclined plane, the pitch-changing speed between the workstations can be changed, and by setting the pitch-changing inclined planes of different inclined wedge blocks to different inclination angles, stepless pitch changes of different spacings between different workstations can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0022] Figure 1 This is the structural diagram of the guide groove type stepless pitch change mechanism;

[0023] Figure 2 This is the structural diagram of the scissor-type stepless pitch-changing mechanism;

[0024] Figure 3 This is a three-dimensional diagram of a backlash-free stepless pitch-changing mechanism according to Embodiment 1 of the present invention;

[0025] Figure 4 1 is a top view of a backlash-free stepless pitch-changing mechanism according to embodiment 1 of the present invention;

[0026] Figure 5 It is a right side view of the stepless pitch-changing mechanism without backlash in Embodiment 1 of the present invention;

[0027] Figure 6 This is a state diagram of the backlash-free stepless pitch-changing mechanism after pitch change in Embodiment 1 of the present invention;

[0028] Figure 7 is a structural diagram of an oblique wedge block according to Embodiment 1 of the present invention;

[0029] Figure 8 is a structural diagram of Embodiment 2 of the present invention;

[0030] Fig. 9 is a structural diagram of Embodiment 3 of the present invention;

[0031] Fig.10 It is a structural diagram of the oblique wedge block of embodiment 4 of the present invention.

[0032] In the figure: 11, guide plate, 12, guide groove, 13, guide rod, 21, shear frame, 22, connecting rod, 31, bottom plate, 32, power plate, 33, first guide rail, 34, second guide rail, 35, inclined wedge block, 351, variable pitch inclined plane, 352, accommodating chamber, 36, tensioning block, 37, magnetically coupled cylinder, 38, fixed station, 39, movable station, 40, third guide rail, 41, servo motor, 42, screw nut pair. DETAILED DESCRIPTION

[0033] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0034] Example 1

[0035] like Figure 3-Figure 7 The embodiment 1 of a backlash-free stepless pitch-changing mechanism of the present invention shown includes a base plate 31, a power plate 32 slidably connected to the base plate 31, a power mechanism for pushing the power plate 32 to move, and a pitch-changing module.

[0036] In order to guide the power plate 32, the bottom plate 31 is provided with a third guide rail 40, and a slider is fixed on the power plate 32, and is slidably mounted on the third guide rail 40 through the slider. The power mechanism mainly pushes the power plate 32 to move along the third guide rail 40. In this embodiment, the power mechanism is: a servo motor 41 installed on the bottom plate 31 and a screw nut pair 42 connected to the output end of the servo motor 41, and the nut of the screw nut pair 42 is connected to the power plate 32. In addition, the power mechanism can also be a hydraulic cylinder, and the output end of the hydraulic cylinder is connected to the power plate 32.

[0037] The power plate 32 is provided with n first guide rails 33 arranged in parallel with each other, the first guide rails 33 and the third guide rails 40 are perpendicular to each other, and the bottom plate 31 is provided with a second guide rail 34 parallel to the first guide rail 33; the variable pitch module comprises: n inclined wedge blocks 35 respectively slidably connected to different first guide rails 33, a fixed station 38 fixed to the bottom plate 31, n movable stations 39 slidably connected to the second guide rails 34, and a tensioning block 36 slidably connected to the second guide rails 34 and abutting against the outer side of the outermost movable station 39, the tensioning block 36 and the magnetic coupling gas The output magnetic rings in the cylinder 37 are attracted to each other; the magnetic coupling cylinder 37 is a rodless cylinder, and an output magnetic ring is fixed on the piston of the magnetic coupling cylinder 37. The tensioning block is attracted to the output magnetic ring in the cylinder on the outer wall surface of the magnetic coupling cylinder 37. By adjusting the pressure on the piston in the cylinder, the tensioning block is kept in a constant force state to always press the active workstation. The front end of the air bevel wedge block 35 has a variable pitch inclined surface 351 in contact with the workstation, and the front end of the bevel wedge block 35 is pressed between two adjacent workstations. The lower side of the nth bevel wedge block 35 has a accommodating cavity 352 that can accommodate the n-1th bevel wedge block 35.

[0038] In this embodiment, two pitch-changing modules are arranged on the power plate 32, and the two pitch-changing modules share the middle fixed station 38. The number of the inclined wedge blocks 35 can be infinitely increased as needed. In this embodiment, each pitch-changing module has four inclined wedge blocks 35 as an example, and the first inclined wedge block 35 is considered to be the smallest-sized inclined wedge block, and the fourth inclined wedge block 35 is considered to be the largest-sized inclined wedge block. Then, the first inclined wedge block 35 can be drilled into the accommodating cavity 352 on the lower side of the second inclined wedge block 35, and so on. The third inclined wedge block 35 can be drilled into the accommodating cavity 352 on the lower side of the fourth inclined wedge block 35.

[0039] In this embodiment, the fourth inclined wedge block 35 of one variable pitch module abuts against the middle fixed station 38, and the first inclined wedge block 35 of the other variable pitch module abuts against the middle fixed station 38, that is, the middle fixed station 38 is respectively provided with a largest-sized inclined wedge block 35 and a smallest-sized inclined wedge block 35 on both sides. For a variable pitch module, each inclined wedge block 35 corresponds to a first guide rail 33, and the largest-sized inclined wedge block 35 is slidably connected to the first guide rail 33 farthest from the station through a slider, and the smallest-sized inclined wedge block 35 is slidably connected to the first guide rail 33 closest to the station through a slider.

[0040] See also Figure 4 In order to adjust the minimum distance between workstations and prevent the sliders under the movable workstation 39 from interfering with each other and affecting the adjustment distance, two parallel second guide rails 34 are provided, and the sliders under adjacent movable workstations 39 are slidably connected to different second guide rails 34 respectively.

[0041] See also Figure 7The inclined wedge block 35 in this embodiment is symmetrically provided with variable pitch inclined surfaces 351. The variable pitch speed between the workstations can be changed by changing the inclination angle of the variable pitch inclined surfaces 351. For example, the larger the angle between the variable pitch inclined surfaces 351 on both sides of the inclined wedge block 35, the faster the distance between the workstations is when the power plate 32 is pushed, and vice versa.

[0042] The position where each station contacts the pitch-changing inclined plane 351 has a guiding inclined plane corresponding to and fitting with the pitch-changing inclined plane 351 , so that the pitch-changing inclined plane 351 can move smoothly within the guiding inclined plane.

[0043] The pitch-changing inclined surfaces 351 of the plurality of inclined wedge blocks 35 in this embodiment have the same inclination angle. Similarly, the pitch-changing inclined surfaces 351 of different inclined wedge blocks 35 can be set to different inclination angles, so as to realize stepless pitch change of different spacings between different workstations.

[0044] The specific working process of Example 1 of the present invention is as follows:

[0045] If you need to adjust the distance between the workstations steplessly, Figure 3 Adjust the status to Figure 5 State, start the servo motor 41, the servo motor 41 rotates to drive the screw of the screw nut pair 42 to rotate, and then drives the nut of the screw nut pair 42 and the power plate 32 fixed on the nut to pull the power plate 32 backward, and under the constant force of the tensioning block 36 squeezing the outermost movable station 39, the guide inclined surface of the movable station 39 is always in contact with the pitch-changing inclined surface 351, and the movable station 39 is constantly gathered toward the middle, and at the same time, multiple inclined wedge blocks 35 are also constantly gathered toward the middle, the inclined wedge block 35 of the pitch-changing module on one side gradually drills into the accommodating cavity 352 of the largest inclined wedge block 35 in the middle, and the inclined wedge block 35 of the pitch-changing module on the other side gradually presses the smallest inclined wedge block 35 in the middle to the bottom, and finally the movable stations 39 gather toward the fixed station 38 in the middle, and the distance between the stations becomes smaller.

[0046] Example 2

[0047] See also Figure 8 In this embodiment, only one variable pitch module can be set on the power plate 32, and the fixed station 38 is on one side. The servo motor 41 drives the power plate 32 to move through the screw nut pair 42, driving each inclined wedge block 35 to move forward and backward. The small inclined wedge block 35 is drilled under the large inclined wedge block 35, so as to realize the gathering and dispersion of multiple movable stations 39 to the fixed station 38 on one side.

[0048] Example 3

[0049] See also Fig. 9 In this embodiment, the fixed workstation 38 is set in the middle, and two sets of variable distance modules are symmetrically arranged with the fixed workstation 38 as the center, so that multiple movable workstations 39 can be gathered to the middle or dispersed to both sides at the same time.

[0050] Example 4

[0051] See also Fig.10 A variable pitch inclined surface 351 is provided on one side of the front end of the inclined wedge block 35, which can also push the movable station 39 to move left and right and adjust the distance between the stations.

[0052] It should be understood that the specific embodiments described above are only used to explain the present invention, and are not used to limit the present invention. Obvious changes or modifications derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A backlash-free stepless pitch-changing mechanism, characterized in that: The invention comprises a base plate (31), a power plate (32) slidably connected to the base plate (31), a power mechanism for pushing the power plate (32) to move, and a pitch-changing module; the power plate (32) is provided with n first guide rails (33) arranged in parallel with each other, and the base plate (31) is provided with second guide rails (34) parallel to the first guide rails (33); the pitch-changing module comprises: n inclined wedge blocks (35) slidably connected to different first guide rails (33), a fixed station (38) fixed to the base plate (31), a sliding connection n movable workstations (39) on the second guide rail (34) and a tensioning block (36) slidably connected to the second guide rail (34) and resting against the outer side surface of the outermost movable workstation (39), the tensioning block (36) being attracted to the output magnetic ring in the magnetic coupling cylinder (37); the front end of the inclined wedge block (35) having a variable pitch inclined surface (351) in contact with the workstation, the front end of the inclined wedge block (35) being pressed between two adjacent workstations, and the lower side of the nth inclined wedge block (35) having a receiving cavity (352) capable of accommodating the n-1th inclined wedge block (35).

2. A backlash-free stepless pitch-changing mechanism according to claim 1, characterized in that: The power mechanism comprises: a servo motor (41) mounted on the base plate (31) and a lead screw nut pair (42) connected to the output end of the servo motor (41), wherein the nut of the lead screw nut pair (42) is connected to the power plate (32).

3. A backlash-free stepless pitch-changing mechanism according to claim 1, characterized in that: The power mechanism is a hydraulic cylinder, and the output end of the hydraulic cylinder is connected to the power plate (32).

4. A backlash-free stepless pitch-changing mechanism according to claim 2 or 3, characterized in that: The bottom plate (31) is provided with a third guide rail (40) which is arranged perpendicularly to the first guide rail (33), and the power plate (32) is slidably connected to the third guide rail (40).

5. The backlash-free stepless pitch-changing mechanism according to claim 1, characterized in that: The second guide rails (34) are two rails arranged in parallel, and adjacent movable workstations (39) are slidably connected to different second guide rails (34).

6. A backlash-free stepless pitch-changing mechanism according to claim 1, characterized in that: Two variable pitch modules are arranged on the power plate (32), and the two variable pitch modules share a fixed station (38) in the middle.

7. A backlash-free stepless pitch-changing mechanism according to claim 6, characterized in that: The pitch-changing module has four inclined wedges (35), wherein the fourth inclined wedge (35) of one pitch-changing module abuts against a fixed station (38) in the middle, and the first inclined wedge (35) of another pitch-changing module abuts against a fixed station (38) in the middle.

8. The backlash-free stepless pitch-changing mechanism according to claim 1, characterized in that: The inclined wedge block (35) is symmetrically provided with variable pitch inclined surfaces (351).

9. The backlash-free stepless pitch-changing mechanism according to claim 1, characterized in that: A variable pitch inclined surface (351) is provided on one side of the inclined wedge block (35).

10. A backlash-free stepless pitch-changing mechanism according to any one of claims 1 to 9, characterized in that: The inclination angles of the variable pitch inclined surfaces (351) of the plurality of inclined wedge blocks (35) are the same.

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