Gear box with controllable reverse driving force

Abstract

The utility model discloses a gear box with controllable reverse driving force, which relates to the technical field of gear box transmission and comprises a box body, a gear transmission mechanism, a transmission sleeve, an output shaft and a damping ring. The gear transmission mechanism comprises a plurality of stages of gears rotationally installed in the box body, and the last stage of gear is fixedly connected with the transmission sleeve. The output shaft is sleeved with the transmission sleeve, and an annular gap between the transmission sleeve and the output shaft is filled with the damping ring. The inner side and the outer side of the damping ring make close contact with the output shaft and the transmission sleeve correspondingly, so that when the reverse drive force does not exceed the threshold value, torque is transmitted through static friction. And when the reverse driving force exceeds a threshold value, at least one of the inner side and the outer side is converted into sliding friction from static friction. Compared with the prior art, the gear box with the controllable reverse driving force has the advantages that the controllable reverse driving force can be realized, and adverse effects caused by backlash can be reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to gear box drive technical field, in particular to a gear box of controllable counter drive force. BACKGROUND

[0002] In recent years, with the rapid development and iterative upgrading of automation and robot industry, the requirements for related transmission devices are continuously improved. Higher requirements are put forward in reducing the backlash influence of gear box transmission related products and controlling the size of mechanism counter drive force.

[0003] The prior art generally adopts the method of reducing the gear center distance to reduce the backlash, which will accelerate the wear of the gear, resulting in the shortening of the service life of the gear box. The counter drive is realized through the reverse transmission of the gear box, but the size of the counter drive force cannot be accurately controlled. UTILITY MODEL CONTENT

[0004] The utility model aims at providing a gear box of controllable counter drive force, realizing the controllable counter drive force.

[0005] To achieve the above-mentioned purpose, the utility model provides the following scheme:

[0006] The utility model discloses a gear box of controllable counter drive force, including the box, gear drive mechanism, transmission sleeve, output shaft and damping ring, gear drive mechanism includes the gear of several stages that rotates and installs in the box, and the last stage gear is fixedly connected with transmission sleeve, transmission sleeve is set up in the output shaft outside, and the annular gap between transmission sleeve and output shaft is filled to the damping ring, and the damping ring is cylindrical ring,

[0007] The inside and outside of the damping ring are in close contact with the output shaft and the transmission sleeve respectively, so as to transmit torque through static friction when the counter drive force does not exceed the threshold value, and at least one side of the inside and outside is changed from static friction to sliding friction when the counter drive force exceeds the threshold value.

[0008] The gear box of controllable counter drive force further includes a rotary damper and a magnetic encoder, the power input end of the rotary damper is fixedly connected with the output shaft, and the shell of the rotary damper is fixedly connected with the box, the magnetic ring of the magnetic encoder is fixedly connected with the output shaft, and the circuit board of the magnetic encoder is fixedly connected with the box.

[0009] Preferably, the gear box of controllable counter drive force further includes a worm, which is rotatably installed in the box, and the worm is matched with the first stage gear of the gear drive mechanism.

[0010] Preferably, the gear box of controllable counter drive force further includes a driving motor, and the rotor of the driving motor is fixedly connected with the worm.

[0011] Preferably, the mounting flange of the driving motor is fixedly connected with the box body, and a buffer pad is arranged between the mounting flange and the box body.

[0012] Preferably, the gear of the gear transmission mechanism is N-stage, N is a positive integer not less than 3, and at least the first N-1 gears are double gears; the large gear of the first gear is matched with the worm, the large gear of the second gear is matched with the small gear of the first gear, and the small gear of the last gear is matched with the small gear of the second gear.

[0013] Preferably, the box body is spliced by a box shell one and a box shell two, and the box shell one and the box shell two are detachably fixedly connected through screws.

[0014] Preferably, one end of the output shaft is provided with a threaded hole, so as to be connected with a load through a screw.

[0015] Preferably, the output shaft is provided with a ring groove for embedding the damping ring.

[0016] The utility model discloses relative to relevant technologies has obtained following technical effect:

[0017] In the utility model, when the counter driving force does not exceed the threshold value, the outside of the transmission sleeve and the damping ring is static friction, and the inside of the output shaft and the damping ring is static friction, and the output shaft will rotate synchronously with the transmission sleeve. When the counter driving force exceeds the threshold value, at least one side of the inside and the outside of the damping ring changes from static friction to sliding friction, and the output shaft and the transmission sleeve rotate relatively. Due to the characteristics that the sliding friction force remains unchanged, the maximum value of the counter driving force is limited, so that the load of the gear transmission mechanism is limited within a certain range, and the gear transmission mechanism is prevented from being damaged due to the excessive counter driving force. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme in the embodiments of the utility model or related technologies, the drawings needed in the embodiments will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can also be obtained according to these drawings without creative labor for those skilled in the art.

[0019] Figure 1 It is a perspective view of the gear box with controllable counter driving force according to an embodiment of the utility model;

[0020] Figure 2 It is another perspective view of the gear box with controllable counter driving force according to an embodiment of the utility model;

[0021] Figure 3 It is a partial structure schematic view of the gear box with controllable counter driving force according to an embodiment of the utility model;

[0022] Figure 4 For Figure 3 Schematic view of another perspective of the structure;

[0023] Figure 5 For Figure 3 Partial schematic view of the structure;

[0024] Figure 6 Schematic view of the output shaft;

[0025] Figure 7 Schematic view of the transmission sleeve.

[0026] In the figure: 1 - box; 2 - gear transmission mechanism; 3 - transmission sleeve; 4 - output shaft; 5 - rotary damper; 6 - worm; 7 - drive motor; 8 - magnetic encoder; 9 - bearing; 11 - box shell one; 12 - box shell two; 21 - primary gear; 22 - secondary gear; 23 - tertiary gear; 31 - cylinder; 32 - flange; 41 - flat shaft end; 42 - magnetic ring mounting end; 43 - ring groove; 61 - light pole end; 71 - mounting flange; 72 - buffer pad; 81 - magnetic ring; 82 - circuit board; 91 - bearing one; 92 - bearing two. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0028] The purpose of the present application is to provide a gear box with controllable counter driving force, so as to realize controllable counter driving force.

[0029] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be described in further detail below with reference to the drawings and specific embodiments.

[0030] With reference to Figures 1-7 The present embodiment provides a gear box with controllable counter driving force, which comprises a box 1, a gear transmission mechanism 2, a transmission sleeve 3, an output shaft 4 and a damping ring. The gear transmission mechanism 2 comprises several levels of gears rotatably installed in the box 1, and the last level of gears is fixedly connected with the transmission sleeve 3. The transmission sleeve 3 is sleeved outside the output shaft 4, and the damping ring fills the annular gap between the transmission sleeve 3 and the output shaft 4. The damping ring is a cylindrical ring.

[0031] The inner and outer sides of the damping ring are in close contact with the output shaft 4 and the transmission sleeve 3, so as to transmit torque through static friction when the counter driving force is less than the threshold value. When the counter driving force exceeds the threshold value, at least one of the inner and outer sides is changed from static friction to sliding friction.

[0032] The counter driving force controllable gearbox further comprises a rotary damper 5 and a magnetic encoder 8. The power input end of the rotary damper 5 is fixedly connected with the output shaft 4, and the shell of the rotary damper 5 is fixedly connected with the box body 1 through screws. The magnetic ring 81 of the magnetic encoder 8 is fixedly connected with the output shaft 4, and the circuit board 82 of the magnetic encoder 8 is fixedly connected with the box body 1.

[0033] The working principle of the counter driving force controllable gearbox in this embodiment is as follows:

[0034] After the power is transmitted to the last stage gear of the gear transmission mechanism 2, the last stage gear is fixedly connected with the transmission sleeve 3, so that the last stage gear drives the transmission sleeve 3 to rotate synchronously.

[0035] When the counter driving force is less than the threshold value, the transmission sleeve 3 and the outer side of the damping ring are in static friction, and the output shaft 4 and the inner side of the damping ring are in static friction, so that the output shaft 4 rotates synchronously with the transmission sleeve 3.

[0036] When the counter driving force exceeds the threshold value, at least one of the inner and outer sides of the damping ring is changed from static friction to sliding friction, and the output shaft 4 and the transmission sleeve 3 rotate relatively. Due to the characteristic that the sliding friction force remains unchanged, the maximum value of the counter driving force is limited, so as to limit the load of the gear transmission mechanism 2 within a certain range, thereby avoiding damage of the gear transmission mechanism 2 due to excessive counter driving force.

[0037] For example, the transmission sleeve 3 has a cylinder 31 and a flange 32 connected to the cylinder 31. The cylinder 31 is externally provided with a bearing 9, and the outer ring of the bearing 9 is fixed to the box body 1. The bearing 9 comprises a bearing one 91 and a bearing two 92, and the flange 32 is located between the bearing one 91 and the bearing two 92. The damping ring is provided with a cut seam at a circumferential position, so as to facilitate assembly. The last stage gear of the gear transmission mechanism 2 is fixedly connected with the flange 32 through screws.

[0038] In this embodiment, the damping ring is not directly arranged between the last stage gear (i.e. the third stage gear 23) and the output shaft 4, but a transmission sleeve 3 is added. The purpose of arranging the transmission sleeve 3 is:

[0039] 1) The length of the transmission sleeve 3 is greater than the length of the last-stage gear, and the damping ring is a cylindrical ring. By providing a greater axial length than the last-stage gear, the arrangement length of the damping ring is not limited by the length of the gear itself, so that a greater number and longer cylindrical ring-shaped damping ring can be assembled. Since the damping ring is a cylindrical ring, the inner and outer sides are in surface contact, which not only solves the problem of gear instability and ensures the coaxiality between the last-stage gear and the output shaft, but also solves the problem of the existing polygonal elastic wire affecting the control of the counterforce due to elastic changes.

[0040] 2) Avoiding slotting on the last-stage gear to avoid stress concentration and ensure the structural strength of the gear;

[0041] 3) The damping ring has a greater contact area with the output shaft 4, thereby better conducting heat to the output shaft 4 and improving the heat dissipation performance.

[0042] It should be noted that when the static friction at the damping ring changes to sliding friction, some associated technical problems also arise, including vibration due to the feeling of frustration when sliding friction occurs, and the problem of monitoring the rotation state of the output shaft.

[0043] The rotary damper 5 can absorb and consume these vibration energies through its own damping action, making the movement of the gear more stable and reducing the vibration and noise caused by the backlash.

[0044] For example, one end of the output shaft 4 is a non-circular cross-section (specifically a flat shaft end 41), and the power input end of the rotary damper 5 is a corresponding non-circular hole, which are inserted and fitted to achieve synchronous rotation. In order to make the drawings more concise, the rotary damper 5 is drawn as a whole and the details are not shown.

[0045] By installing the magnetic ring 81 of the magnetic encoder 8 on the output shaft 4, the control accuracy of the output shaft 4 will not be affected in the case of controllable counterforce.

[0046] For example, the magnetic ring 81 is sleeved on the end of the output shaft 4 away from the rotary damper 5, which extends out of the box 1 and has a stage for installing the magnetic ring 81.

[0047] As a possible example, in this embodiment, the controllable counterforce gearbox further includes a worm 6, which is rotatably installed in the box 1, and the worm 6 cooperates with the first-stage gear of the gear transmission mechanism 2. The cooperation between the worm 6 and the first-stage gear is similar to the cooperation between the worm 6 and the worm gear, which realizes the power input of the gear transmission mechanism 2. At this time, the controllable counterforce gearbox is used as a reduction gearbox.

[0048] It should be noted that when the lead angle of the worm 6 is less than the equivalent friction angle between the meshing teeth, the worm 6 has self-locking property, and if the gear transmission mechanism 2 reverses rotation, it will inevitably cause damage to the gear transmission mechanism 2 or the worm 6. In the embodiment, the damping ring is arranged to eliminate the synchronous rotation of the transmission sleeve 3 and the output shaft 4, so as to protect the gear transmission mechanism 2 and the worm 6 when the output shaft 4 reverses rotation.

[0049] As a possible example, in the embodiment, the gear box with controllable counter driving force further comprises a driving motor 7, and a rotor of the driving motor 7 is fixedly connected with the worm 6.

[0050] For example, an end of the worm 6 away from the driving motor 7 is a light pole end 61, the light pole end 61 extends into the limiting groove and is matched with the shaft sleeve in the limiting groove.

[0051] As a possible example, in the embodiment, a mounting flange 71 of the driving motor 7 is fixedly connected with the box body 1, and a buffer pad 72 is arranged between the mounting flange 71 and the box body 1.

[0052] The buffer pad 72 can absorb the vibration energy generated when the driving motor 7 works, so that the movement of the driving motor 7 is more stable, and the vibration and noise caused by the driving motor 7 are reduced.

[0053] As a possible example, in the embodiment, the gear of the gear transmission mechanism 2 is N levels, N is a positive integer not less than 3, and at least the first N-1 gears are double gears. The large gear of the first gear is matched with the worm 6, the large gear of the second gear is matched with the small gear of the first gear, and the last gear is matched with the small gear of the first gear.

[0054] By adopting the arrangement mode of the gear transmission mechanism 2, the gear transmission mechanism 2 can achieve the effect of speed reduction. It can be understood that those skilled in the art can also select other forms of gear transmission mechanism 2 according to different actual needs.

[0055] For example, the gear of the gear transmission mechanism 2 is three levels (i.e. N=3), which are a first gear 21, a second gear 22 and a third gear 23, and the first gear 21 and the second gear 22 are double gears.

[0056] As a possible example, in the embodiment, the box body 1 is spliced by a box shell one 11 and a box shell two 12, and the box shell one 11 and the box shell two 12 are fixedly connected by screws in a detachable manner.

[0057] As a possible example, in the embodiment, one end of the output shaft 4 is provided with a threaded hole, so as to connect a load by a screw, and realize the synchronous rotation of the output shaft 4 and the load.

[0058] As a possible example, in the embodiment, the output shaft 4 is provided with ring grooves 43 for embedding the damping rings, and the ring grooves 43 can limit the axial position of the damping rings.

[0059] Exemplarily, the number of the ring grooves 43 is two, and one damping ring is arranged in each of the two ring grooves 43.

[0060] Exemplarily, the length of the transmission sleeve 3 is less than the length of the output shaft 4, and the part of the output shaft 4 located in the box 1 is not inserted into the transmission sleeve 3, but is inserted into a corresponding shaft sleeve in the box 1, and the shaft sleeve is positioned by a corresponding positioning groove in the box 1. The shaft sleeve is separated from the transmission sleeve 3 by a gasket to avoid direct friction between the shaft sleeve and the end face of the transmission sleeve 3.

[0061] The principle and implementation mode of the present application are described by using specific examples in the present application, and the above embodiment is only used to help understand the method and core idea of the present application. Meanwhile, for the general skilled in the art, the specific implementation mode and application range will be changed according to the idea of the present application. In conclusion, the content of the present application should not be understood as a limitation of the present application.

Claims

1. A backdrivable gearbox, characterized in that, The gear box comprises a box body, a gear transmission mechanism, a transmission sleeve, an output shaft and a damping ring; the gear transmission mechanism comprises several stages of gears rotatably installed in the box body, and the last stage of gears is fixedly connected with the transmission sleeve; the transmission sleeve is sleeved outside the output shaft, and the damping ring fills the annular gap between the transmission sleeve and the output shaft; the damping ring is a cylindrical ring; The inner and outer sides of the damping ring are in close contact with the output shaft and the transmission sleeve respectively, so as to transmit torque through static friction when the counter driving force does not exceed the threshold value; when the counter driving force exceeds the threshold value, at least one of the inner and outer sides is changed from static friction to sliding friction; The gear box with controllable counter driving force further comprises a rotary damper and a magnetic encoder; the power input end of the rotary damper is fixedly connected with the output shaft, and the shell of the rotary damper is fixedly connected with the box body; the magnetic ring of the magnetic encoder is fixedly connected with the output shaft, and the circuit board of the magnetic encoder is fixedly connected with the box body.

2. The backdrivable gearbox of claim 1, wherein: Further comprising a worm, which is rotatably installed in the box body and cooperates with the first stage of gears of the gear transmission mechanism.

3. The backdrivability controllable gearbox of claim 2, wherein: Further comprising a driving motor, the rotor of which is fixedly connected with the worm.

4. The backdrivable gearbox of claim 3, wherein: The mounting flange of the driving motor is fixedly connected with the box body, and a buffer pad is arranged between the mounting flange and the box body.

5. The backdrivability controllable gearbox of claim 2, wherein: The gears of the gear transmission mechanism are N stages, N is a positive integer not less than 3, and at least the first N-1 stages of gears are double gears; the large gear of the first stage of gears cooperates with the worm, the large gear of the next stage of gears cooperates with the pinion of the previous stage of gears, and the last stage of gears cooperates with the pinion of the previous stage of gears.

6. The backdrivability controllable gearbox of claim 1, wherein: The box body is composed of a box shell one and a box shell two, and the box shell one and the box shell two are fixedly connected by screws.

7. The backdrivability controllable gearbox of claim 1, wherein: One end of the output shaft is provided with a threaded hole to connect the load by screws.

8. The backdrivability controllable gearbox of claim 1, wherein: An annular groove is arranged on the output shaft for embedding the damping ring.

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