CN105905828A - Electromagnetic brake device and elevator - Google Patents

Abstract

The present invention provides an electromagnetic brake device capable of improving the brake responsiveness based on a simple structure. By means of a second movable element (102) on the opposite side of a first movable element (101) and a second force applying part (15), the second movable member (102) is separated from a stator (8) before or during the separation of the first movable element (101) and the stator (8).

Description

Electromagnetic braking device and elevator

technical field

The present invention relates to an electromagnetic braking device and an elevator using the electromagnetic braking device.

Background technique

Generally, a hoist for raising and lowering an elevator car, a control device, and a governor for detecting an overspeed of the car are installed in a machine room provided in an upper part of a building. However, machine-room-less elevators that do not have a machine room are also gaining popularity among elevators that have a short lift stroke and a slow car lift-off speed.

In the case of an elevator without a machine room, equipment such as a hoist and a control device conventionally arranged in a machine room are arranged in the elevator shaft. Here, the space in the elevator shaft is limited, and there are various shapes and installation methods of the hoist. For example, there is an elevator in which the section of the hoist and the car overlaps in the lowermost or uppermost part of the elevator shaft, or an elevator in which the section of the hoist and the car do not overlap. Usually, the gap between the car and the elevator shaft is only about a few hundred millimeters. Therefore, in order to install the hoist in the gap, a flat hoist is required, and a so-called thin hoist is used.

For the above-mentioned thin hoist, a direct-acting electromagnetic brake device that presses a pad against a brake drum is widely used. For example, there is an electromagnetic brake device described in Patent Document 1 as an electromagnetic brake device that brakes by pressing the outer peripheral surface of a brake drum in a hoisting machine of an elevator. In addition, there is an electromagnetic brake device described in Patent Document 2 as an electromagnetic brake device that brakes by pressing the inner surface of a brake drum in an elevator hoisting machine. In addition, as a device related to a disc type electromagnetic brake device, there is an electromagnetic brake device described in Patent Document 3.

In the electromagnetic brakes of Patent Documents 1, 2, and 3, during emergency braking, the contacts of the circuit are disconnected to cut off the power supply, thereby reducing the current, thereby releasing the brake and obtaining a braking force. The braking force has a relationship of "braking force = brake spring force - electromagnetic force". Therefore, in order to sufficiently transmit the braking force to the brake drum during braking, it is necessary to sufficiently reduce the electromagnetic force. However, when the power is turned off, the magnetic flux on the magnetic pole surface changes to generate an eddy current. Due to the influence of the eddy current, it takes a long time to reduce the electromagnetic force, and thus the responsiveness of the braking force transmission decreases.

Therefore, there is a device described in Patent Document 4 as an electromagnetic brake device aimed at improving responsiveness. In Patent Document 4, it is described that a motion assisting unit is included. The time response of the motion assisting unit is faster than that of the braking electromagnet after receiving the braking command, that is, after the power is cut off. Reduce the electromagnetic force of the braking electromagnet before the braking action of the body starts.

Here, Patent Document 4 describes three methods as motion assisting means. The motion assisting unit of the first aspect is composed of a piezoelectric element provided in the fixed iron core to apply a reaction force to the movable iron core so that the movable iron core moves in a direction away from the fixed iron core. Before the moving electromagnet starts the braking action, it operates to expand the gap between the fixed iron core and the movable iron core of the braking electromagnet. The motion assisting unit of the second form is used to apply a reaction force to the movable iron core so that the movable iron core moves in a direction away from the fixed iron core, and is composed of a small electromagnet smaller than the braking electromagnet. Before the braking electromagnet starts the braking operation, it operates to widen the gap between the fixed iron core and the movable iron core of the braking electromagnet. The action assisting unit of the third mode is composed of a small electromagnet smaller than the braking electromagnet. With this small electromagnet, before the braking electromagnet starts the braking action, the brake is activated by the movable iron core installed on the small electromagnet. The fixed iron core of the electromagnet is connected with the movable iron core and operates so that the magnetic flux of the fixed iron core and the movable iron core of the braking electromagnet bypasses to the movable iron core of the small electromagnet.

prior art literature

patent documents

Patent Document 1: International Publication No. WO2011/004468

Patent Document 2: Japanese Patent Laid-Open No. 2002-284486

Patent Document 3: International Publication No. WO2010/143298

Patent Document 4: Japanese Patent Laid-Open No. 2008-286333

Contents of the invention

The technical problem to be solved by the invention

However, the motion assisting unit described in Patent Document 4 is composed of a piezoelectric element or a small electromagnet. Therefore, it is necessary to separately apply a voltage for driving the motion assisting unit, and there is a problem that the structure is complicated. In addition, when a small electromagnet is used, there is a problem that it is necessary to separately install the small electromagnet on the outside of the structural elements of the conventional electromagnetic brake device.

An object of the present invention is to provide an electromagnetic brake device that improves responsiveness during braking with a simple structure.

Technical solutions to technical problems

In order to achieve the above object, the electromagnetic braking device of the present invention includes, for example, a braked body, a brake pad that presses against the braked body, and a brake pad that separates the brake pad from the braked body. An electromagnet composed of a coil and a stator is characterized in that it has a first movable element, a first biasing part, a second movable element, and a second biasing part, and the first movable element and the brake The pads are connected to press the brake pads toward the braked body, and the first biasing portion is disposed between the first movable element and the stator and applies the first biasing portion The movable element is separated from the stator to apply a force that presses the brake pad toward the braked body, and the second movable element is arranged on the stator and the first movable element. On the opposite side of the element and does not have the function of pressing the brake pad toward the braked body, the second force applying part is arranged between the second movable element and the stator and applies A force that separates the second movable element from the stator, at the same time as or before the separation of the first movable element from the stator, at the start of braking, the second movable element from the stator Stator separation.

In addition, the elevator of the present invention includes, for example, a hoist including the electromagnetic brake device, and a car lifted and lowered by the hoist.

Invention effect

According to the present invention, with the second movable member and the second urging portion provided on the opposite side of the first movable member, at the start of braking, the second movable member is separated from the stator at the same time as or before the first movable member is separated from the stator. The movable element is separated from the stator, therefore, the reluctance of the magnetic circuit formed during braking can be increased, the time constant of the magnetic flux flowing in the magnetic circuit can be reduced, and the electromagnetic force can be shortened enough to become small Therefore, the responsiveness during braking can be improved. In addition, the above-mentioned effects can be achieved by a simple structure of adding a second movable element and a second urging portion provided on the opposite side of the first movable element.

Description of drawings

Fig. 1 is a sectional view showing an electromagnetic brake device according to Embodiment 1 of the present invention.

2 is a cross-sectional view illustrating the operation of the electromagnetic brake device and the magnetic circuit of the magnetic circuit according to the first embodiment.

3 is a graph showing the relationship between electromagnetic force and time (magnetic field analysis results) in Example 1 and a conventional example.

4 is a cross-sectional view illustrating the operation of the electromagnetic brake device and the magnetic circuit of the magnetic circuit according to Embodiment 2 of the present invention.

Fig. 5 is a sectional view showing an electromagnetic brake device according to Embodiment 3 of the present invention.

6 is a cross-sectional view illustrating the operation of the electromagnetic brake device according to the third embodiment.

7 is a cross-sectional view illustrating the operation of the electromagnetic brake device according to the third embodiment.

Fig. 8 is a perspective view illustrating an example of an elevator to which the present invention is applied.

Fig. 9 is a plan view and a cross-sectional view of a conventional electromagnetic brake device.

Fig. 10 is a sectional view illustrating the operation of a conventional electromagnetic brake device.

FIG. 11 is a diagram illustrating the operation of the conventional electromagnetic brake device and the magnetic circuit of the magnetic circuit.

detailed description

Embodiments of the present invention will be described below with reference to the drawings. In addition, in each drawing and each embodiment, the same or similar constituent elements are given the same reference numerals and their descriptions are omitted.

[Example 1]

Fig. 8 is a perspective view illustrating an example of an elevator to which the present invention is applied. In FIG. 8 , an elevator without a machine room is taken as an example for description. The elevator has a hoist 3 including an electromagnetic brake device 4 , and a car 1 raised and lowered by the hoist 3 . The car 1 is raised and lowered via a plurality of cables 5 wound around a pulley 6 of a hoist 3 . The pulley 6 is directly connected to the shaft of an unillustrated driving device, and is driven by the driving device. The brake drum 7 as the braked body is directly connected to the pulley 6 , and the brake drum 7 is braked by the electromagnetic brake device 4 , thereby controlling the movement of the car 1 . 2 is counterweight block.

First, before describing the electromagnetic brake device according to Embodiment 1 of the present invention, the configuration of a conventional electromagnetic brake device will be described. 9 is a top view and a cross-sectional view of a conventional electromagnetic braking device, FIG. 9( a ) is a top view, and FIG. 9( b ) is a cross-sectional view along line A-A of FIG. 9( a ). Using this FIG. 9 , the structure of the non-excitation operation type brake device will be described.

In Fig. 9, the electromagnetic braking device 4 includes a stator 8 made of magnetic bodies, a movable element 9, a coil 10, a spring 11, a gap adjustment mechanism with adjusting bolts 12a, 12b, brake shoes 13, and brake pads. 14. The spring 11 is attached in advance in a state compressed from a free length. In addition, an electromagnet is constituted by the coil 10 and the stator 8 .

Fig. 10 is a sectional view illustrating the operation of a conventional electromagnetic brake device.

FIG. 10( a ) shows a state in which the electromagnetic brake device 4 brakes the hoisting machine 3 . In the braking state, when braking, the pressing force of the spring 11 presses the brake pad 14 toward the brake drum 7 via the movable element 9 , thereby braking the pulley 6 .

Fig. 10(b) shows the state at the time of non-braking. When not braking, the stator 8 is magnetized by applying a current to the coil 10 . By magnetizing the stator 8, the movable element 9 is attracted to the stator 8 side, the brake pad 14 is separated from the brake drum 7, and the pressing force is released.

As described above, the braking action is performed mechanically by the spring 11, and the release of the braking force is performed electrically. In this way, when the power supply is stopped due to a power failure or the like, a fail-safe operation in which the car 1 stops is realized.

Fig. 1 is a sectional view showing an electromagnetic brake device according to Embodiment 1 of the present invention. The basic structure of the electromagnetic brake device 4 of the first embodiment is the same as that of the conventional non-excitation actuation type brake device, but as shown in FIG. The movable element located between the brake drum 7 and the stator 8 is set as the first movable element 101, and the movable element located on the other side (the opposite side of the stator 8 to the first movable element 101) sandwiches the stator 8 The movable element is set as the second movable element 102 . On the first movable element 101 there is a spring 11 which exerts a force in the direction of separation from the stator 8 and in the braking direction. That is, the electromagnetic brake device 4 of Embodiment 1 includes the brake drum 7 as the body to be braked, the brake pad 14 that presses the body to be braked, and the brake pad 14 that separates the body from the body to be braked. The electromagnet composed of the coil 10 and the stator 8 has a first movable element 101 that is connected to the brake pad 14 and presses the brake pad 14 toward the body to be braked, and is arranged on the first movable element. Between 101 and stator 8 , spring 11 is a first biasing portion that applies a force that presses brake pad 14 toward a body to be braked by applying a force that separates first movable element 101 from stator 8 .

On the other hand, between the second movable element 102 and the stator 8, there are springs 15 (15a, 15b) which are second urging parts that apply a force for separating the second movable element 102 from the stator 8 . In addition, the second movable element 102 does not have the function of pressing the brake pad 14 toward the body to be braked.

Fig. 2 is a sectional view illustrating the operation of the electromagnetic brake device and the magnetic circuit of the magnetic circuit according to the first embodiment of the present invention. Fig. 2(a) is the brake release state, and shows the state transfer to the braking action in the order of (a), (b) and (c). When the brake starts, the power supply is cut off from the brake release state (Fig. 2(a)), the electromagnetic force drops, and the active force of the spring 15 acting on the second movable element 102 exceeds the electromagnetic force, so that the second movable element 102 Element 102 is separated from stator 8 (Fig. 2(b)). Then, or substantially simultaneously with the action of the second movable element 102, the electromagnetic force acting on the first movable element 101 is lower than the biasing force of the spring 11, so that the first movable element 101 moves in the braking direction (Fig. 2(c)).

Next, the action of Example 1 will be described. In Example 1, as shown in FIG. 2 , the flow of the magnetic flux flowing through the magnetic circuit changes like the magnetic circuits 17 a , 17 b , and 17 c indicated by dotted arrows. The magnetic circuit 17 a in FIG. 2( a ) passes through the stator 8 , the first movable element 101 and the second movable element 102 . Next, in the state of FIG. 2( b), the second movable element 102 is separated from the stator 8, thereby creating a gap, and therefore, the magnetic circuit 17b is divided into a magnetic circuit passing through the upper side of the coil 10 inside the stator 8, and There are two magnetic circuits that pass through the gap in the stator 8 and then pass through the second movable element 102 and then return to the stator 8 through the gap. Since the magnetic circuit passes through the gap on the second movable element side, the magnetic resistance at this time is larger than that of the magnetic circuit 17a in FIG. 2( a ). In addition, in the state shown in FIG. 2( c ), a gap is formed between the first movable element 101 side and the stator 8 , and as a result, the magnetic resistance is further increased.

In contrast, FIG. 11 is a diagram illustrating the operation of the conventional electromagnetic brake device and the magnetic circuit of the magnetic circuit. FIG. 11(a) is in the same state as FIG. 10(b), and FIG. 11(b) is the same as The state of Fig. 10(a) is the same. As shown in FIG. 11( b ), the magnetic circuit 18 of the magnetic circuit of the existing structure is a path that passes through the gap in the stator 8 and returns to the stator 8 through the movable element 9 .

Fig. 2(d) shows a state where the first movable element 101 is separated from the stator 8 earlier than the second movable element 102, and the magnetic circuit 17d of the magnetic circuit becomes a state similar to that of Fig. 11(b) of the conventional example. . Assuming that the sum of the thickness of the stator 8 in Fig. 2 and the thickness of the second movable element 102 is the same as the thickness of the stator 8 of Fig. 11 (b), then Fig. 2 (d) and Fig. 11 (b) become equivalent states, The same applies to magnetic resistance. In addition, the magnetic resistance in the state of FIG. 2( d ) is larger than that in the state of FIG. 2( a ) because it passes through the gap on the side of the first movable element 101 .

Here, if the magnetic resistance is large, the time constant T of the magnetic flux change becomes small, and the responsiveness of the magnetic flux becomes good. Furthermore, since the electromagnetic force is proportional to the square of the flowing magnetic flux, it is possible to shorten the fall time of the electromagnetic force by improving the responsiveness of the magnetic flux. As a result, assuming that the sum of the thickness of the stator 8 in Fig. 2 and the thickness of the second movable element 102 is the same as the thickness of the stator 8 of Fig. 11 (b), then in the state of Fig. 2 (b), the conventional Compared with Fig. 11(b) of Fig. 2 and Fig. 2(d) in which the first movable element 101 is separated first, the first movable element 101 can be separated from the stator 8 quickly, and the braking response is better. In addition, even in the transient state after the first movable element 101 is separated from the stator 8 as shown in FIG. Responsiveness is also better.

3 is a graph showing the relationship between electromagnetic force and time (magnetic field analysis results) in Example 1 and a conventional example. It is the result of analyzing the change of the electromagnetic force under the following conditions by simulation: the sum of the thickness of the stator 8 in Fig. 2 and the thickness of the second movable element 102 and the thickness of the stator 8 of Fig. 11 (b) Under the same conditions, Embodiment 1 fixes the size of the gap in the state of FIG. 2(c), and the existing structure fixes the gap as the first movable element 101 in FIG. 2(c) in FIG. 11(b). The same size as the side, set the electromagnetic force at time zero as 1, and cut off the power supply to the electromagnet at the moment of time 0.05 seconds. It can be seen from FIG. 3 that, compared with the existing structure, the electromagnetic force of Embodiment 1 decreases faster. As a result, the responsiveness of braking at the start of braking can be improved.

Next, the case of shifting to the brake release state will be described. When the brake is released, the state can also be transferred in the order of Figure 2(c), (b), (a), but in this case, compared with Figure 2(d), the reluctance is larger, so, The response of the electromagnetic force is late, creating a new problem of time-consuming brake release. There is no problem if the response time is within the allowable range, but if the response time cannot be tolerated, a large magnetomotive force is required when the brake is released to increase the size of the electromagnetic brake device 4 .

Therefore, in Embodiment 1, preferably when the brake is released, the states are transferred in the order of Fig. 2(c), (d), (a), that is, the first movable element 101 and the second movable element 101 are connected by electromagnets. The movable element 102 is attracted to the stator 8 , and the second movable element 102 abuts on the stator 8 earlier than the first movable element 101 . Thereby, the reluctance can be reduced to a state close to that of the conventional FIG. 11( b ), and the responsiveness at the time of brake release can be maintained at the same level as the conventional one.

In addition, regarding the timing at which the first movable element 101 and the second movable element 102 are respectively activated when the brake is started and when the brake is released, that is, which movable element is to be activated first, the spring 11 , the active force of 15, the size of the gap, the thickness of the magnetic body of the stator 8 between the coil 10 and the second movable element 102, etc. are all related, but basically, the springs 11, 15 can be set properly The force to set the action timing. Therefore, it can also be set to transfer in the order of Fig. 2 (a), (b), (c) when the brake starts, and transfer according to the sequence of Fig. 2 (c), (d) and (c) when the brake is released. a) Sequential transfer. Here, regarding the urging force of the spring 11, the set value required to generate the required braking force according to the specifications of the elevator is determined to some extent, and the degree of freedom in setting is small. On the other hand, regarding the active force of the spring 15, since the second movable element 102 does not press the brake pad 14 toward the braked body, it has no influence on the braking force after the transient response ends, so the setting degree of freedom is greater.

As described above, according to Embodiment 1, the responsiveness at the time of braking can be improved with a simple structure. In addition, when the operation at the time of brake release is appropriately set, a decrease in responsiveness at the time of brake release can be suppressed.

[Example 2]

4 is a cross-sectional view illustrating the operation of the electromagnetic brake device and the magnetic circuit of the magnetic circuit according to Embodiment 2 of the present invention. Embodiment 2 differs from Embodiment 1 in that a non-magnetic material such as a non-magnetic material bar 20 is provided in a region of the stator 8 between the coil 10 and the second movable element 102 .

Fig. 4 (a), Fig. 4 (b), Fig. 4 (c) correspond to Fig. 2 (a), Fig. 2 (b), Fig. 2 (c) respectively, in Fig. 4 (c), the magnetic circuit 19 is not The magnetic body 20 does not pass through the inside of the stator 8, but only becomes a path passing through the second movable element 102 from the gap. As a result, compared with the case of the first embodiment, the magnetic resistance at the start of braking can be increased, and the responsiveness can be further improved. Others are basically the same as those in Embodiment 1, and therefore descriptions thereof are omitted.

[Example 3]

Fig. 5 is a sectional view showing an electromagnetic brake device according to Embodiment 3 of the present invention. In Embodiments 1 and 2, the body to be braked is a brake drum, and braking force is generated by pressing in a direction perpendicular to the rotating shaft. In contrast, Example 3 is a structure in which braking is performed by pinching the brake disc 22 as a braked body.

In FIG. 5 , 23 a and 23 b are brake pads, 13 a and 13 b are brake shoes, 30 is a slide pin, 25 is a main body, 21 is a fixing part, and 28 is a restricting member fixed to the fixing part 21 . As shown in FIG. 5 , brake pads 23 a and 23 b are arranged so as to sandwich the brake disc 22 , one of which is supported by the first movable element 101 , and the other is supported by the main body 25 by the connecting pin 24 . In addition, the main body 25 is connected to the core body 31 by bolts 26 . In addition, the core body 31 corresponds to the stator 8 in the first and second embodiments.

Next, the operation of the third embodiment will be described using FIGS. 5 , 6 , and 7 . Figure 5 is the brake release state, which is equivalent to the state in Figure 2(a), Figure 6 is the transition state after the brake starts, which is equivalent to the state in Figure 2(b), and Figure 7 is the braking state, which is equivalent to the state in Figure 2(b). 2(c) status. Since the operations and effects of the basic parts are the same as those of the first embodiment, description thereof will be omitted. In addition, the structure of the non-magnetic strip 20 of the second embodiment can also be applied to the third embodiment.

As mentioned above, although the Example of this invention was described, the structure demonstrated in each Example so far is an example only, and this invention can be changed suitably within the range which does not deviate from a technical idea. In addition, the configurations described in the respective embodiments may be used in combination as long as they do not contradict each other.

Label description

1 car

2 pairs of weights

3 hoists

4 Electromagnetic brake device

5 cables

6 pulleys

7 brake drum

8 stator

9 movable elements

10 coils

11 springs

12a, 12b Adjusting bolts

13, 13a, 13b brake shoe

14 Brake pads

15, 15a, 15b spring

17a, 17b, 17c, 17d The magnetic circuit of the magnetic circuit of Embodiment 1

18 The magnetic circuit of the magnetic circuit of the existing structure

19 The magnetic circuit of the magnetic circuit of embodiment 2

20 non-magnetic strips

21 fixed part

22 brake disc

23a, 23b Brake pads

24 link pin

25 subjects

26 bolts

27 elastic member

28 Limiting member

29 bearings

30 sliding pin

31 Core

101 First movable element

102 Second movable element

Claims (7)

1. an electro-magnetic braking device, this electro-magnetic braking device includes braked body, is braked towards described The Brake pad of body pressing and make that described Brake pad separates with described braked body by coil and fixed The electromagnet that son is constituted, described electro-magnetic braking device is characterised by,

There is the first moving element, the first force section, the second moving element and the second force section, described First moving element links with described Brake pad and is pressed towards described braked body by described Brake pad Pressure, described first force section is arranged between described first moving element and described stator and by applying The power making described first moving element separate with described stator applies described Brake pad towards described quilt The power of brake body pressing, described second moving element is arranged in the movable with described first first of described stator Side that part is contrary and not there is the effect pressed towards described braked body by described Brake pad, described Second force section is arranged between described second moving element and described stator and apply to make described second can The power that dynamic element separates with described stator,

Braking start time, while described first moving element separates with described stator or before, Described second moving element separates with described stator.

2. electro-magnetic braking device as claimed in claim 1, it is characterised in that

When braking is unclamped, utilize described electromagnet by movable to described first moving element and described second unit Part is attracted to described stator, and described second moving element is than described first moving element elder generation and institute State stator to abut.

3. electro-magnetic braking device as claimed in claim 1, it is characterised in that

Described stator, region between described coil and described second moving element is provided with Nonmagnetic material.

4. electro-magnetic braking device as claimed in claim 1, it is characterised in that

Described first force section and described second force section are spring.

5. electro-magnetic braking device as claimed in claim 1, it is characterised in that

Described braked body is brake drum.

6. electro-magnetic braking device as claimed in claim 1, it is characterised in that

Described braked body is brake disc.

7. an elevator, it is characterised in that

Have include the electro-magnetic braking device as described in any one of claim 1 to 6 hoist engine and The car lifted is carried out by described hoist engine.