Small-size large-magnetic-force electromagnetic brake

Abstract

The electromagnetic brake comprises a brake disc, an armature, a stator, an electromagnetic coil and a compressed spring, the stator is provided with a stator inner cavity, a stator protruding column protruding towards the direction close to the armature is arranged in the middle of the cavity wall of one side of the stator inner cavity, and the stator protruding column is provided with a protruding column through hole. The electromagnetic coil is arranged in the stator inner cavity and sleeved on the stator protruding column, the compression spring is sleeved outside the stator protruding column and located in a central through hole of the electromagnetic coil, an armature protruding ring is arranged in the middle of the surface of one side of the armature, part or all of the armature protruding ring is arranged in the protruding column through hole, and the armature and the brake disc are both located in the stator inner cavity. The electromagnetic force of the electromagnetic coil to the armature is increased on the premise that the volumes of the electromagnetic coil and the brake are not increased, the requirements of small volume and large magnetic force can be met at the same time, enough distance between the armature and the stator can be ensured, the armature and the brake disc can be thoroughly separated when the brake is released, and the service life of the brake is prolonged. And friction noise between the brake disc and the armature is eliminated.

Description

Technical Field

[0001] The utility model belongs to the technical field of electromagnetic brake production, and in particular relates to an electromagnetic brake with small volume and large magnetic force. Background Art

[0002] An electromagnetic brake is a brake that uses electromagnetic force to achieve a braking function. Its basic structure includes a brake disc, an armature, a stator, an electromagnetic coil and a spring. The brake disc is connected to a rotating shaft or a transmission shaft. The electromagnetic coil and the spring are respectively installed in the stator. The spring generates a thrust (or a pull) on the armature, thereby achieving the armature's function of clamping the brake (or releasing the brake) on the brake disc. The electromagnetic coil generates a magnetic field when energized. The magnetic field generates an electromagnetic force on the armature that is opposite to the spring force. The electromagnetic force overcomes the spring force and generates a pulling force (or a thrust) on the armature, thereby achieving the armature's function of releasing the brake (or clamping the brake) on the brake disc.

[0003] The electromagnetic force of the electromagnetic coil of the electromagnetic brake on the armature must be greater than the elastic force of the spring, and the elastic force of the spring is closely related to the braking effect. There is a certain gap between the armature and the stator of the traditional electromagnetic brake and there is no overlapping part. The electromagnetic force of the electromagnetic coil on the armature is inversely proportional to the distance between the two. If the distance between the armature and the stator is too small, it is difficult to ensure that the armature and the brake disc are completely separated when the brake is released. If the armature and the brake disc are not completely separated, it may cause increased equipment operation resistance and noise. If the distance between the armature and the stator is too large, the brake volume will increase due to the increase in the coil, and the braking efficiency will also be reduced. Therefore, it is difficult for traditional electromagnetic brakes to meet the requirements of small volume and large magnetic force at the same time.

[0004] In addition, in some specific applications, the braking time needs to be limited, that is, it must have a high braking efficiency and a small brake volume. The braking efficiency of the electromagnetic brake is inversely proportional to the braking time, that is, the smaller the braking time, the higher the braking efficiency. The armature and the brake disc of the traditional electromagnetic brake are in plane contact and the direction of the spring force is perpendicular to the plane. The rotation of the brake disc has no limiting structure. Under the premise of a certain friction coefficient, improving the braking efficiency can only be achieved by increasing the braking torque, which will inevitably increase the spring force and electromagnetic force, so it will inevitably lead to an increase in the brake volume. Therefore, it is difficult for traditional electromagnetic brakes to simultaneously meet the requirements of small volume and high braking efficiency. Utility Model Content

[0005] The purpose of the utility model is to provide a small-volume and large-magnetic-force electromagnetic brake with a small electromagnetic coil but large electromagnetic force in order to solve the above problems.

[0006] The utility model achieves the above-mentioned purpose through the following technical solutions:

[0007] A small-volume, high-magnetic-force electromagnetic brake comprises a brake disc, an armature, a stator, an electromagnetic coil and a compression spring, wherein the armature is located between the brake disc and the stator, the electromagnetic coil and the compression spring are installed in the stator, one end of the compression spring contacts the armature, the armature can move in the direction of approaching and moving away from the stator and cannot rotate relative to the stator, the stator is provided with a stator inner cavity, a side of the stator inner cavity close to the armature is opened, a stator boss protruding in the direction close to the armature is provided in the middle of the cavity wall on the side of the stator inner cavity away from the armature, the stator boss is provided with a boss through hole with two ends penetrating, the electromagnetic coil is placed in the stator The stator is in the inner cavity of the stator and is sleeved on the stator boss through its own central through hole. A side cavity wall of the stator inner cavity is provided with a lead through hole that passes through the inside and outside, and the lead of the electromagnetic coil passes through the lead through hole. The spiral compression spring is sleeved on the outside of the stator boss and is located in the central through hole of the electromagnetic coil. An armature convex ring is provided in the middle of the side surface of the armature close to the stator, and the armature through hole passes through the armature convex ring. Part or all of the armature convex ring is placed in the boss through hole and can slide axially in the boss through hole. The circumferential outer wall of the armature convex ring contacts with the hole wall of the boss through hole. The armature and the brake disc are both located in the stator inner cavity.

[0008] Preferably, in order to more stably and reliably install the compression spring under the premise of ensuring normal axial movement of the armature, the armature convex ring includes a small-diameter convex ring and a large-diameter convex ring that are integrally formed and axially arranged, the outer diameter of the small-diameter convex ring is smaller than the outer diameter of the large-diameter convex ring, the large-diameter convex ring is connected to the armature and is integrally formed, the small-diameter convex ring is placed in the boss through hole and can slide axially in the boss through hole, the circumferential outer wall of the small-diameter convex ring is in contact with the hole wall of the boss through hole, the outer diameter of the large-diameter convex ring is larger than the hole diameter of the boss through hole, and the compression spring is simultaneously mounted on the outside of the stator boss and the outside of the large-diameter convex ring.

[0009] Preferably, in order to prevent the compression spring from affecting the installation of the electromagnetic coil, a concave annular step is provided on the circumferential outer wall of the stator boss and the compression spring is sleeved outside the annular step.

[0010] Preferably, in order to facilitate the installation of the brake disc and other components and reduce the axial dimension to reduce the volume of the brake, and at the same time to reliably position the armature to avoid its rotation relative to the stator, the small-volume, high-magnetic-force electromagnetic brake also includes a mounting seat and a brake shaft, the brake shaft is rotatably mounted on the mounting seat, the brake disc is mounted on the brake shaft through its own center through hole and cannot rotate relative to the brake shaft, the armature is provided with an armature through hole for the brake shaft to pass through, the four corners of the armature are respectively provided with positioning notches, the four corners of the stator are respectively provided with connecting through holes, the screws of the four connecting bolts respectively pass through the four connecting through holes and the four positioning notches and are connected to the four corresponding screw holes on the mounting seat.

[0011] Preferably, in order to prevent the brake disc and the brake shaft from rotating relative to each other, the circumferential outer wall surface of the brake shaft and the wall surface of the central through hole of the brake disc are respectively provided with a mutually matching plane.

[0012] Preferably, in order to quickly connect the brake disc and the brake shaft, an annular groove is provided on the circumferential outer wall of the brake shaft, and a clamping ring is placed in the groove to achieve axial positioning of the brake disc.

[0013] Preferably, in order to precisely control the braking efficiency, a surface on one side of the armature close to the brake disc is provided with a plurality of bosses evenly distributed along the circumferential direction, the outer circumferential surface of the bosses is a conical surface, a surface on one side of the brake disc close to the armature is provided with a plurality of arc grooves evenly distributed along the circumferential direction, the center of the circle where the arc groove is located overlaps with the center of the brake disc, the groove wall surface of the arc groove is a conical surface and has the same taper as the outer circumferential surface of the bosses, the plurality of bosses are respectively placed in a corresponding plurality of the arc grooves, the bosses are in close contact with the groove walls of the corresponding arc grooves or in close contact with the friction plates provided on the groove walls of the corresponding arc grooves.

[0014] Preferably, in order to ensure smooth braking while improving braking efficiency, there are two bosses and two arc-shaped grooves.

[0015] The beneficial effects of the utility model are:

[0016] The utility model arranges an axial sliding structure in which a convex ring and a through hole cooperate between the armature and the stator. On the one hand, the positioning installation of the armature is realized without increasing the axial size of the brake. On the other hand, the armature convex ring and the electromagnetic coil form a partially overlapping structure, which increases the electromagnetic force of the electromagnetic coil on the armature without increasing the volume of the electromagnetic coil and the brake. The requirements of small volume and large magnetic force can be met at the same time, and it can be ensured that there is a sufficient distance between the armature and the stator under the premise that the brake can be released normally, so as to ensure that the armature and the brake disc are completely separated when the brake is released, reduce the running resistance of the equipment, and eliminate the friction noise between the brake disc and the armature.

[0017] In addition, the utility model provides a plurality of bosses with conical outer surfaces on the armature, and a plurality of arc-shaped grooves with conical groove wall surfaces on the brake disc. When braking, the plurality of bosses are respectively placed in the plurality of arc-shaped grooves and are in close contact through the conical surfaces. Under the pressure of the compression spring, the conical surface cooperation can realize rapid braking of the brake disc. At the same time, by utilizing the limiting structure of the arc-shaped groove, after the brake disc rotates a certain angle and significantly decelerates, rapid and accurate braking is realized by utilizing the limiting cooperation of the boss and the arc-shaped groove, and finally the purpose of improving the braking efficiency is achieved without increasing the friction coefficient and the volume of the brake, and the requirements of smaller volume and higher braking efficiency can be met at the same time. At the same time, the conical surface cooperation between the boss and the arc-shaped groove can avoid the problem of the boss and the arc-shaped groove being stuck when the brake is released, and ensure that the electromagnetic force generated by the electromagnetic coil can attract the armature to release it tightly from the stator, completely release the brake, facilitate the free rotation of the brake disc and completely eliminate the friction noise with the armature during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a three-dimensional exploded view of the small-volume and high-magnetic-force electromagnetic brake of the utility model before assembly;

[0019] Figure 2 This is a three-dimensional diagram of the armature of the small-volume and large-magnetic-force electromagnetic brake of the utility model. Figure 1 Different and proportionally larger;

[0020] Figure 3 This is a three-dimensional diagram of the stator of the small-volume and large-magnetic-force electromagnetic brake of the utility model. Figure 1 Different and proportionally larger;

[0021] Figure 4 This is one of the partially cutaway stereoscopic views of the small-volume and large-magnetic-force electromagnetic brake of the utility model after assembly, in which the brake is in a braking state;

[0022] Figure 5 This is the second partially cutaway stereoscopic view of the small-volume, high-magnetic-force electromagnetic brake of the utility model after assembly, in which the brake is in a released state. DETAILED DESCRIPTION

[0023] The utility model is further described below in conjunction with the accompanying drawings:

[0024] like Figure 1-Figure 5 As shown, the small-volume and high-magnetic-force electromagnetic brake of the utility model comprises a brake disc 14, an armature 10, a stator 2, an electromagnetic coil 6 and a compression spring 7, the armature 10 is located between the brake disc 14 and the stator 2, the electromagnetic coil 6 and the compression spring 7 are installed in the stator 2, one end of the compression spring 7 is in contact with the armature 10, the armature 10 can move in the direction of approaching and moving away from the stator 2 and cannot rotate relative to the stator 2, the stator 2 is provided with a stator inner cavity 18, a side of the stator inner cavity 18 close to the armature 10 is opened, a stator boss 19 protruding toward the direction close to the armature 10 is provided in the middle of the cavity wall on the side of the stator inner cavity 18 away from the armature 10, the stator boss 19 is provided with a boss through hole 4 with two ends penetrating, and the electromagnetic coil 6 is placed in the stator inner cavity 18. And it is sleeved on the stator boss 19 through its own central through hole, one side cavity wall of the stator inner cavity 18 is provided with a lead through hole 5 that passes through the inside and outside, and the lead wire of the electromagnetic coil 6 (not marked in the figure) passes through the lead through hole 5, the spiral compression spring 7 is sleeved on the outside of the stator boss 19 and is located in the central through hole of the electromagnetic coil 6, an armature convex ring (refer to the small diameter convex ring 8 and the large diameter convex ring 9 described below) is provided in the middle of the side surface of the armature 10 close to the stator 2, and the armature through hole passes through the armature convex ring, part or all of the armature convex ring is placed in the boss through hole 4 and can slide axially in the boss through hole 4, the circumferential outer wall of the armature convex ring is in contact with the hole wall of the boss through hole 4, and the armature 10 and the brake disc 14 are both located in the stator inner cavity 18.

[0025] like Figure 1-Figure 5 As shown, the utility model also discloses the following more optimized specific structures:

[0026] In order to install the compression spring 7 more stably and reliably under the premise of ensuring the normal axial movement of the armature 10, the armature convex ring includes a small-diameter convex ring 8 and a large-diameter convex ring 9 that are integrally formed and axially arranged. The outer diameter of the small-diameter convex ring 8 is smaller than the outer diameter of the large-diameter convex ring 9. The large-diameter convex ring 9 is connected to the armature 10 and is integrally formed. The small-diameter convex ring 8 is placed in the boss through hole 4 and can slide axially in the boss through hole 4. The circumferential outer wall of the small-diameter convex ring 8 is in contact with the hole wall of the boss through hole 4. The outer diameter of the large-diameter convex ring 9 is larger than the hole diameter of the boss through hole 4. The compression spring 7 is simultaneously mounted on the outside of the stator boss 19 and the outside of the large-diameter convex ring 9.

[0027] In order to prevent the compression spring 7 from affecting the installation of the electromagnetic coil 6, an inwardly concave annular step (not marked in the figure) is provided on the circumferential outer wall of the stator boss 19 and the compression spring 7 is sleeved outside the annular step.

[0028] In order to facilitate the installation of the brake disc 14 and other components and reduce the axial dimension to reduce the volume of the brake, and at the same time to reliably position the armature 10 to avoid its rotation relative to the stator 2, the small-volume electromagnetic brake with high-efficiency braking also includes a mounting seat 16 and a brake shaft 15. The brake shaft 15 is rotatably mounted on the mounting seat 16, and the brake disc 14 is mounted on the brake shaft 15 through its own center through hole and cannot rotate relative to the brake shaft 15. The armature 10 is provided with an armature through hole (not marked in the figure) for the brake shaft 15 to pass through, and the four corners of the armature 10 are respectively provided with positioning notches 11, and the four corners of the stator 2 are respectively provided with connecting through holes 3, and the screws of the four connecting bolts 1 are respectively connected to the four corresponding screw holes on the mounting seat 16 after passing through the four connecting through holes 3 and the four positioning notches 11.

[0029] In order to prevent the brake disc 14 and the brake shaft 15 from rotating relative to each other, the circumferential outer wall surface of the brake shaft 15 and the wall surface of the central through hole of the brake disc 14 are respectively provided with a mutually matching plane (not marked in the figure).

[0030] In order to quickly connect the brake disc 14 and the brake shaft 15 , an annular groove (not marked in the figure) is provided on the circumferential outer wall of the brake shaft 15 , and the clamping ring 12 is placed in the groove (not marked in the figure) to achieve axial positioning of the brake disc 14 .

[0031] In order to accurately control the braking efficiency, a side surface of the armature 10 close to the brake disc 14 is provided with a plurality of bosses 17 evenly distributed in the circumferential direction, and the outer peripheral surface of the boss 17 is a conical surface. A side surface of the brake disc 14 close to the armature 10 is provided with a plurality of arc grooves 13 evenly distributed in the circumferential direction, and a partition portion is provided between two adjacent arc grooves 13. The bottom of the arc groove 13 is closed or passes through the brake disc 14, and the center of the circle where the arc groove 13 is located overlaps with the center of the brake disc 14. The groove wall surface of the arc groove 13 is a conical surface and has the same taper as the outer peripheral surface of the boss 17. The plurality of bosses 17 are respectively placed in a plurality of arc grooves 13 corresponding to each other, and the bosses 17 are in close contact with the groove walls of the corresponding arc grooves 13 (and can also be in close contact with the friction plate provided on the groove walls of the corresponding arc grooves 13).

[0032] In order to ensure smooth braking while improving braking efficiency, there are two bosses 17 and two arc-shaped grooves 13 .

[0033] like Figure 1-Figure 5As shown, when in use, the brake shaft 15 is connected to the rotating shaft of the braking device. During normal operation, the brake needs to be released, the electromagnetic coil 6 is energized, an electromagnetic field is generated, and an electromagnetic attraction is generated on the armature 10 and the armature convex ring. Because the electromagnetic coil 6 overlaps with a part of the armature convex ring and the distance is very close, the electromagnetic attraction generated is very large, which can completely overcome the elastic force of the compression spring 7 to separate the boss 17 from the arc groove 13, and move the armature 10 close to the stator 2, the brake disc 14 is completely separated from the armature 10, and the brake is in a released state; when braking is required, the electromagnetic coil 6 loses power, the electromagnetic attraction disappears, and the compression spring 7 pushes the armature 10 to move in the direction close to the brake disc 14. If the boss 17 corresponds to the partition between two adjacent arc grooves 13, because the brake disc 14 is in a high-speed rotation state, the boss 17 can quickly correspond to the arc groove 13 and enter the arc groove 13, and the conical surface between the two. Under the cooperation, the boss 17 and the groove wall of the arc groove 13 (or the corresponding friction plate) are quickly squeezed to form a strong friction force, and the rotation speed of the brake disc 14 drops rapidly. If the speed of the brake disc 14 is not very fast, or the rotational inertia of the corresponding equipment shaft (related to the driven load mass) is not very large, it is very likely that the boss 17 is still in contact with the end groove wall of the arc groove 13 to complete the braking. If the speed of the brake disc 14 is faster, or the rotational inertia of the corresponding equipment shaft is larger, then after the speed of the brake disc 14 drops rapidly, the boss 17 is still required to contact the end groove wall of the arc groove 13 to complete the braking. Since the arc groove 13 limits the rotation of the boss 17, forced rapid braking can be achieved (after the speed of the brake disc 14 drops rapidly, there will not be too much impact force between the boss 17 and the end groove wall of the arc groove 13, and the relevant components will not be damaged), so compared with the traditional structure, the braking time is reduced and the braking efficiency is improved.

[0034] The above embodiments are only preferred embodiments of the present utility model and are not limitations on the technical solutions of the present utility model. Any technical solution that can be implemented on the basis of the above embodiments without creative work should be deemed to fall within the scope of protection of the patent of the present utility model.

Claims

1. An electromagnetic brake with a small volume and large magnetic force, comprising a brake disc, an armature, a stator, an electromagnetic coil and a compression spring, wherein the armature is located between the brake disc and the stator, the electromagnetic coil and the compression spring are installed in the stator, one end of the compression spring contacts the armature, the armature can move in a direction close to and away from the stator and cannot rotate relative to the stator, and is characterized in that: The stator is provided with a stator inner cavity, a side of the stator inner cavity close to the armature is opened, a stator boss protruding in the direction close to the armature is provided in the middle of the cavity wall on the side of the stator inner cavity away from the armature, the stator boss is provided with a boss through hole with two ends penetrating, the electromagnetic coil is placed in the stator inner cavity and is sleeved on the stator boss through its own center through hole, a cavity wall on one side of the stator inner cavity is provided with a lead through hole penetrating inside and outside, and the lead of the electromagnetic coil passes through the lead through hole, the spiral compression spring is sleeved outside the stator boss and is located in the center through hole of the electromagnetic coil, an armature convex ring is provided in the middle of the surface of one side of the armature close to the stator, and the armature through hole passes through the armature convex ring, part or all of the armature convex ring is placed in the convex through hole and can slide axially in the convex through hole, the circumferential outer wall of the armature convex ring is in contact with the hole wall of the convex through hole, and the armature and the brake disc are both located in the stator inner cavity.

2. The small-volume and large-magnetic-force electromagnetic brake according to claim 1 is characterized in that: The armature convex ring includes a small-diameter convex ring and a large-diameter convex ring that are integrally formed and axially arranged, the outer diameter of the small-diameter convex ring is smaller than the outer diameter of the large-diameter convex ring, the large-diameter convex ring is connected to the armature and is integrally formed, the small-diameter convex ring is placed in the boss through hole and can slide axially in the boss through hole, the circumferential outer wall of the small-diameter convex ring is in contact with the hole wall of the boss through hole, the outer diameter of the large-diameter convex ring is larger than the hole diameter of the boss through hole, and the compression spring is simultaneously mounted on the outside of the stator boss and the outside of the large-diameter convex ring.

3. The small-volume and large-magnetic-force electromagnetic brake according to claim 2 is characterized in that: An inwardly concave annular step is arranged on the circumferential outer wall of the stator boss and the compression spring is sleeved outside the annular step.

4. The small-volume and high-magnetic-force electromagnetic brake according to claim 1, 2 or 3, characterized in that: The small-volume, high-magnetic-force electromagnetic brake also includes a mounting seat and a brake shaft, the brake shaft is rotatably mounted on the mounting seat, the brake disc is sleeved on the brake shaft through its own center through hole and cannot rotate relative to the brake shaft, the armature is provided with an armature through hole for the brake shaft to pass through, the four corners of the armature are respectively provided with positioning notches, the four corners of the stator are respectively provided with connecting through holes, the screw rods of the four connecting bolts respectively pass through the four connecting through holes and the four positioning notches and are connected to the four corresponding screw holes on the mounting seat.

5. The small-volume and large-magnetic-force electromagnetic brake according to claim 4 is characterized in that: The circumferential outer wall surface of the brake shaft and the wall surface of the central through hole of the brake disc are respectively provided with a plane that matches with each other.

6. The small-volume and large-magnetic-force electromagnetic brake according to claim 5, characterized in that: An annular clamping groove is arranged on the circumferential outer wall of the brake shaft, and a clamping ring is arranged in the clamping groove to realize axial positioning of the brake disc.

7. The small-volume and high-magnetic-force electromagnetic brake according to claim 1, 2 or 3, characterized in that: A plurality of bosses evenly distributed along the circumferential direction are provided on one side surface of the armature close to the brake disc, and the outer peripheral surface of the bosses is a conical surface. A plurality of arc grooves evenly distributed along the circumferential direction are provided on one side surface of the brake disc close to the armature, and the center of the circle where the arc groove is located overlaps with the center of the brake disc. The groove wall surface of the arc groove is a conical surface and has the same taper as the outer peripheral surface of the bosses. The plurality of bosses are respectively placed in a plurality of corresponding arc grooves, and the bosses are in close contact with the groove walls of the corresponding arc grooves or in close contact with the friction plates provided on the groove walls of the corresponding arc grooves.

8. The small-volume and large-magnetic-force electromagnetic brake according to claim 7, characterized in that: There are two bosses and two arc-shaped grooves.

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