JP2006199479A - Winch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a winch having a brake system which hardly causes any secular change, and is free from troubles such as heat generation and waste oil processing, capable of suppressing energy consumption, and excellent in safety. <P>SOLUTION: The winch to vertically move the load by winding wire ropes 9, 33 around a winding part 1 comprises a main brake 3 consisting of an electromagnetic brake which is in a released state from the rotational motion of the winding part when a motor is driven, and put into motion to apply the braking force to the winding part when stopping the input in the motor, and an auxiliary brake 5 consisting of an electromagnetic brake which is in a released state from the rotational motion of the winding part when the motor is driven, and put into motion to apply the braking force to the winding part when stopping the input in the motor in addition to the main brake. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a winch, and more particularly, to a winch having a brake mechanism with little temporal change.

  For example, in an electric winch (friction winding type winch) used for a gondola, an electromagnetic brake is incorporated in order to hold a load at the time of stopping. Further, in the case of the above-mentioned gondola, according to Article 30 of the Gondola Structural Standard No. 120 of the Ministry of Labor Notification No. 120 (December 25, 2000), the gondola is (a1) a speed of 1.3 corresponding to a predetermined allowable lowering speed. A device that automatically controls the speed before exceeding twice, or (a2) When the speed corresponding to the allowable lowering speed reaches 1.4 times, the work floor is automatically lowered. It is necessary to provide a device for stopping the movement (Non-Patent Document 1).

  A winch used for a gondola or the like is provided with an auxiliary brake in addition to the main electromagnetic brake. This auxiliary brake plays a role of a speed control device for complying with the above-mentioned regulations (a1) and (a2).

Conventionally, the following types of automatic brakes have been used as auxiliary brakes. Each of these auxiliary brakes has the following problems. These automatic brakes forming the auxiliary brake are included in the category of the friction brake mechanism, and a detailed description of the mechanism is given (see Non-Patent Document 2). Hereinafter, the problems of the automatic brakes (B1) to (B4) will be briefly described.
(B1) Screw brake Since the brake is intermittently activated during the descent operation, it generates heat. This heat generation reduces the friction coefficient of the brake lining, making it difficult to obtain a normal braking force. In particular, in recent years, winches tend to be miniaturized, and the temperature rise due to heat generation has increased and is regarded as important. The problem of temperature rise due to heat generation accompanying the downsizing is a problem common to a disc brake using a one-way clutch, which will be described below.

In general, grease is applied to the brake lining portion or immersed in lubricating oil. For this reason, it is necessary to periodically replace the lubricating oil, and it is necessary to treat the waste oil in consideration of environmental problems.
(B2) Claw wheel and claw (disc brake using one-way clutch)
During the descent operation, heat is generated because the brake is always in the activated state. Even in this brake, the friction coefficient of the brake lining decreases due to heat generation, and it is difficult to obtain a normal braking force. The application of grease, the use of lubricating oil, its periodic replacement, and the treatment of waste oil are problematic as in (B1).
(B3) Centrifugal brake Although the load can be suspended and lowered at a constant speed by adjusting the brake force of the centrifugal brake, the load cannot be held in the air fishing state. Application of grease, use of lubricating oil, periodic replacement thereof, and disposal of waste oil are problematic as in (B1) and (B2).
(B4) Self-locking The self-locking function can be obtained only in a reduction gear using a worm gear. In this case, since the mechanical efficiency is poor, it is necessary to attach a motor having a larger output than a spur gear reducer or the like. As a result, unnecessary power consumption occurs.
Gondola Safety Rules and Gondola Structural Standards, page 123, April 20, 2001, first edition, 3rd edition, edited by the Japan Crane Association Nobuo Nakane "Machine Design / Vol.7 Spring / Buffer / Brake" Seikodo Shinkosha (published April 30, 1966, 1st edition)

  The above-mentioned auxiliary brakes (B1), (B2) and (B3) all utilize the frictional force of the brake lining, and structurally exert a braking force on the winding part constantly or continuously during descending operation. Yes. That is, the brake is applied. For this reason, it is easy to produce a change with time.

  As described above, the auxiliary brake has a problem more than that of the main brake even though it is an auxiliary brake, and a solution to the above problem has been desired.

  It is an object of the present invention to provide a winch having a brake system that is less likely to change with time, has no problems such as heat generation and waste oil treatment, and has excellent energy efficiency, and has excellent safety.

  The winch of the present invention is a winch in which a wire rope is wound around a winding portion, and the winding portion is rotationally driven by an electric motor to move the load up and down. The winch is in a released state with respect to the rotational movement of the winding portion when the electric motor is driven, and enters the operation of applying a braking force to the winding portion when the input to the electric motor is stopped. In addition to the first electromagnetic brake, when the motor is driven, it is in a released state with respect to the rotational movement of the winding portion, and exerts a braking force on the winding portion when the input to the motor is stopped. And a second electromagnetic brake that enters operation.

  According to the above configuration, the first and second electromagnetic brakes are always in the released state while the load is moved up and down, so that heat is not generated due to friction at the brake lining portion or the like. For this reason, there is no reduction in the friction coefficient due to heat generation. Further, in the case of an electromagnetic brake, since the electromagnetic brake is in a released state that does not exert a braking force on the winding portion during operation of the electric motor, lubrication with grease, oil, or the like is unnecessary. For this reason, problems such as waste oil treatment do not occur.

  Here, “being in a released state with respect to the rotational motion of the winding portion” means that the rotational motion of the winding portion driven by the electric motor does not exert a restraining force, resistance force, restraining force, or the like. In addition, “entering an operation of applying a braking force to the winding portion when the input to the electric motor is stopped” refers to the following operation. When the input to the electric motor is stopped, such as turning off the power switch, the electric motor itself is rotated by a load caused by attractive force (gravity). This state means that the load is in a state of starting free fall. The brake provided to prevent free fall operates at this time, and applies a braking force to the winding portion so that the load does not fall freely. The above-described operation means that the electromagnetic brake enters an operation of applying a braking force to the winding portion.

  In the first and second electromagnetic brakes, the load force may actually be borne by either one or both of the first and second electromagnetic brakes. For example, if the timing for applying the braking force to the winding portion of one electromagnetic brake is earlier than the timing for the other electromagnetic brake and the load is loaded first, the load is actually loaded first. The electromagnetic brake that has started to operate in the above-mentioned manner, and the electromagnetic brake that has subsequently entered the above-described operation, although performing the same operation, does not actually bear the load. In some cases, both electromagnetic brakes simultaneously bear the load. In this case, the load is actually borne by both electromagnetic brakes.

  Therefore, when a sudden drop occurs, for example, when the electric motor stops and a free fall occurs, the first and / or second electromagnetic brakes enter an operation for holding the load and actually bear the load. At this time, even if the first electromagnetic brake is unlikely to operate, the second electromagnetic brake prevents the gondola from dropping. As a result, both the provisions of Article 30 (a1) and (a2) of the gondola structure standard of the Ministry of Labor Notification No. 120 (December 25, 2000) can be satisfied.

  In the second electromagnetic brake, the timing at which the braking force is applied to the winding portion when the input to the motor is stopped is the same as that of the winding portion when the input to the motor is stopped in the first electromagnetic brake. It can be made later than the timing at which the braking force is applied.

  In the above case, when the input to the electric motor is stopped, the load is first held by the first electromagnetic brake. That is, the first electromagnetic brake is the main brake. Next, the second electromagnetic brake (auxiliary brake) for assisting the first electromagnetic brake starts its operation and enters the operation for applying the braking force. As long as the main brake operates normally, the second electromagnetic brake, which is an auxiliary brake, does not bear a load, but actually bears a load only when the main brake fails and functions as a brake. As a result, the burden on the auxiliary brake is limited only when the main brake fails, and an efficient and lean auxiliary brake can be obtained. Moreover, the auxiliary brake excellent in durability can be obtained.

  By using the present invention, a winch provided with a brake system that suppresses secular change and has excellent safety after solving the problems of heat generation and waste oil, which have been problems in the past, and the problem of high power consumption. Can be provided.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a winch in an embodiment of the present invention. In the winch 10, the hanging wire rope 9 is wound around the winding portion 1 and moves up and down with a load according to the rotation direction of the electric motor (motor) 7. The main brake 3 composed of an electromagnetic brake is disposed in the vicinity of the electric motor 7, and the auxiliary brake 5 composed of an electromagnetic brake is positioned so as to sandwich the winding portion at a position on the opposite side. Between the electric motor 7 and the winding part 1, the reduction gear 8 which decelerates the rotational speed of an electric motor and transmits to the winding part 1 is arrange | positioned. The positional relationship between the main brake 3 and the auxiliary brake 5 may take any arrangement.

  FIG. 2 is a cross-sectional configuration diagram of the auxiliary brake 5. In FIG. 2, when no current flows through the coil 27 and the electromagnet does not operate, the armature 21 is pressed by the brake spring 25 to press the brake disk 23, and the brake disk 23 is pressed against the side plate 31 to be in a braking state. In this state, when the electric motor is not operating and the main brake cannot hold a load, the auxiliary brake 5 can hold the load.

  When power is supplied to the auxiliary brake 5, the coil 27 is excited and the armature 21 overcomes the force of the braking spring 25 and is attracted to the field core 29. When the armature 21 is sucked by the field core 29, the brake disk 23 pressed against the side plate 31 is released, and braking is released. That is, in the above-mentioned “released state”, a current flows through the electromagnet of the electromagnetic brake, and this corresponds to a state where the armature 21 is attracted to the electromagnet. Further, the state in which the braking force is applied to the wound portion corresponds to the state in which the supply of current to the electromagnet is cut off and the armature 21 is pressed against the brake disc 23 by the braking spring 25. Further, “entering an operation of applying a braking force to the winding portion” refers to an operation of interrupting the supply of current to the electromagnet.

  Next, a circuit including the electric motor 7, the main brake 3, and the auxiliary brake 5 will be described. As described above, in the released state, a direct current is passed through the coil of the electromagnetic brake to operate the electromagnet. Usually, a three-phase AC motor is used as the motor 7, but a single-phase motor or other electric motor may be used. For this reason, when using an electromagnetic brake for a winch and taking an electric current from the alternating current power supply of a motor, an alternating current direct current converter is used. In FIG. 3, the AC / DC converter (P1) 11 of the main brake (B1) 3 is powered from the upstream side of the switch 15 with respect to the motor 7, and the AC / DC converter (P2) 13 of the auxiliary brake (B2) 5 is The power source is taken from the downstream side of the switch 15. However, the AC / DC converter (P1) 11 of the main brake (B1) 3 may be powered from the downstream side of the switch 15 with respect to the motor 7.

  Referring to FIG. 3, when input to motor 7 is stopped, for example, when switch 15 is opened and turned off, relay switch 17 is also opened and turned off. Therefore, when the switch 15 is turned off, the power to both the main brake 3 and the auxiliary brake 5 is cut off. However, in the main brake 3, the relay switch 17 is located on the downstream side of the AC / DC converter 11, and therefore cuts off DC. On the other hand, on the auxiliary brake 5 side, the AC / DC converter 13 is interrupted by a switch 15 for AC that is located upstream of the AC / DC converter 13. For this reason, the main brake 3 is interrupted by direct current and the auxiliary brake 5 is interrupted by alternating current. DC interruption is referred to as “DC switching” and AC interruption is referred to as “AC switching”. In particular, in AC interruption, the simultaneous interruption of the motor power supply is referred to as “AC simultaneous interruption”.

  The above-described DC switching and AC switching simultaneously for the electromagnetic brake results in the following release time difference. As soon as the switch 15 is turned off, the armature 21 is pushed by the braking spring 25 and the main brake 3 enters a system for holding a load. As shown in FIG. 4, the release time of the DC switching is, for example, 0.03 seconds. Here, the release time refers to the time from when the switch 15 is turned off until the action of the braking spring begins to occur. Further, in the case of simultaneous AC switching, the release time is 0.25 seconds, which requires 8 times longer than DC switching. As a result, the main brake enters the winch braking with a short release time, and substantially holds the load and the weight of the winch itself, while the auxiliary brake enters the winch braking system at a later timing. enter. For this reason, even if the armature or the like is pressed against the braking position, the auxiliary brake is not substantially subjected to the braking load because the load is borne by the main brake. The auxiliary brake substantially bears the load only when the main brake does not bear the load before the auxiliary brake due to a failure or the like. However, if the main brake and the auxiliary brake are shut off at the same release time, both brakes may partially bear the load.

  Next, a brake operation flowchart in the present embodiment will be described with reference to FIGS. First, the case where the winch performs the ascending operation will be described with reference to FIG. First, the switch 15 is turned on to operate the motor, current is supplied to the main brake (B1) and the auxiliary brake (B2), the braking is released, and the brake is released. The motor rolls up and moves up. If the switch 15 is turned off during this ascent, the main brake, which has a release time of 0.03 seconds, enters braking as described above. The motor stops rotating at a later transition time. When the motor is stopped, the main brake is already in effect, so there is no risk of free fall. After the switch 15 is turned off, the auxiliary brake is activated with a release time of 0.25 seconds.

  According to the above flow chart, as long as the main brake maintains normal operation, the auxiliary brake does not function as a brake to hold a load. However, once the main brake has failed and braking by the main brake is not performed, braking by the auxiliary brake is realized. For this reason, since it operates when it should operate as an auxiliary brake and does not usually bear a load, durability can be improved.

  FIG. 6 is a flowchart in a case where the winch performs a descending operation. First, the switch 15 is turned on to operate the motor, current is supplied to the main brake (B1) and the auxiliary brake (B2), the braking is released, and the brake is released. The motor rotates downward and descends. If the switch 15 is turned off during this lowering, as described above, the main brake with a release time of 0.03 seconds is put into braking. The motor stops rotating at a later transition time. When the motor is stopped, the main brake is already in effect, so there is no risk of free fall. After the switch 15 is turned off, the auxiliary brake is activated with a release time of 0.25 seconds.

  According to the above flow chart, as long as the main brake maintains normal operation, the auxiliary brake does not function as a brake to hold a load. However, once the main brake has failed and braking by the main brake is not performed, braking by the auxiliary brake is realized.

  As described above, since the auxiliary brake actually bears the load only when the main brake fails, it is necessary to consider a procedure for confirming whether the auxiliary brake operates normally. FIG. 7 is a flowchart for confirming the operation of the auxiliary brake. First, the main brake 3 is forcibly released. Next, the switch 15 is turned on to start the descent operation. At this time, the main brake 3 is forcibly released and the auxiliary brake 5 is released according to the switch-on state. When the winch is descending, turn the switch off. After this, the main brake with a short release time tries to operate, but does not operate because it is forcibly released. During this time (within the release time of the auxiliary brake), the motor is not in an electrically operated state, but continues to rotate in the descending direction due to the load. Thereafter, when the release time of the auxiliary brake has elapsed, the auxiliary brake enters the braking state. As a result, the load is held by the auxiliary brake, and the rotation of the motor stops. By executing the above program, it is possible to confirm whether the auxiliary brake operates normally.

  Next, a connection method different from the above for the main brake 3, the auxiliary brake 5, and the motor will be described. FIG. 8 is a circuit diagram in which the main brake 3 is switched off by alternating current and the auxiliary brake 5 is switched off simultaneously. As shown in FIG. 8, the AC separate cut is an AC side of the AC / DC converter 11 on the main brake 3 side, and an input is cut off by a relay switch 17 different from the power supply switch 15 to the motor. The simultaneous AC switching in the auxiliary brake 5 is different from the above AC separate switching in that the AC side of the AC / DC converter 13 is blocked by the power supply switch 15 to the motor. In the case of simultaneous AC disconnection, the release time will be longer than in the case of AC separate disconnection.

  FIG. 9 is a diagram showing the release time for the above-mentioned AC switching in comparison with the other two blocking methods. The release time for AC switching is a value between DC switching and AC simultaneous switching. That is, the release time for DC switching was 0.03 seconds, which was the shortest, and AC simultaneous switching was 0.25 seconds, but for AC switching, it was 0.12 seconds. It has become. For this reason, the release time of the main brake 0.12 seconds is almost half of the release time of the auxiliary brake 0.25 seconds, and after the main brake holds the load, the auxiliary brake operates to hold the load. . For this reason, as long as the main brake operates normally, the auxiliary brake does not actually bear the load. Note that the release time shown in FIG. 4 and FIG. 9 differs depending on the model of the motor and the AC / DC converter, and is shown only as an example.

  FIG. 10 is a diagram showing still another method of connecting the main brake 3, the auxiliary brake 5, and the motor. In the example of FIG. 10, DC switching is performed on the main brake 3 side, while AC switching is switched on the auxiliary brake 5 side. Therefore, the release time of the main brake 3 is 0.03 seconds, the release time of the auxiliary brake 5 is 0.12 seconds, and the release time of the main brake 3 can also be shortened.

  As described above, by configuring both the main brake and the auxiliary brake with electromagnetic brakes, it is possible to solve the problems that have conventionally occurred. (B1) Screw brake, (B2) Claw wheel and claw (disc brake using a one-way clutch), (B3) Centrifugal brake, etc. (1) Brake heat generation during descent operation and brake lining caused by this heat generation Problems such as a decrease in the coefficient of friction and (2) periodic replacement of lubricating oil and disposal of waste oil can be solved. Further, (B4) it is possible to prevent an increase in power consumption of the worm gear used for the self-locking reduction gear.

  11 to 13 are perspective views showing a winch according to an embodiment of the present invention. FIG. 11 is a diagram showing a gondola 35 that moves up and down with workers on the outer walls and windows of a high-rise building. An operator rides on the gondola 35, operates and stops the winch 10 by the operation panel 37, and the gondola including the winch moves up and down and stops while winding the wire rope 33 around the winch. As described above, both the main brake and the auxiliary brake of the electromagnetic brake are incorporated in the winch 10, and the main brake normally operates. However, if the main brake does not operate, the auxiliary brake loads the load. It can bear and maintain a stop state. In other words, the double arrangement of electromagnetic brakes can ensure excellent safety while eliminating the problems of conventional heat generation and waste oil.

  FIG. 12 is a diagram showing a winch that moves the load up and down. In this case, unlike the winch of FIG. 11, the winch 10 itself does not move but rotates the winding portion while being fixed at a predetermined position, and feeds and winds the wire rope 33 to move the load up and down. Can do. In the case of this winch, both the main brake and auxiliary brake of the electromagnetic brake are incorporated, and the above-described effects can be obtained.

  FIG. 13 shows a winch 10 in which the winch 10 moves up and down while winding the wire rope 33. A load is attached to the winch and moves up and down according to the up and down movement of the winch. This winch also incorporates two electromagnetic brakes constituting a main brake and an auxiliary brake. In this case, the main brake normally operates, but if the main brake does not operate, the auxiliary brake can bear the load and maintain the stopped state. As a result, the double arrangement of the electromagnetic brakes can ensure excellent safety while solving the problems of conventional heat generation and waste oil.

  14 to 18 are diagrams showing the arrangement of the winding unit 1, the motor 7, the main brake 3, and the auxiliary brake 5. FIGS. 14A to 18A are front views, and FIGS. 14B to 18B are partial cross-sectional views. In the configuration shown in FIGS. 14A and 14B, the main brake 3 and the auxiliary brake 5 are arranged so as to sandwich the winding portion 1 and the motor 7 from the outside. In the winches shown in FIGS. 14A and 14B, two electromagnetic brakes are divided into left and right with the emphasis on the difficulty of transferring heat generated from the main brake to the auxiliary brake.

  The winches shown in FIGS. 15A and 15B are views showing winches used as shown in FIG. 11 or FIG. A reduction gear 8 is provided, and a winding unit 1, a motor 7, a main brake 3, and an auxiliary brake 5 are provided. The winch is suspended from the wire rope 33 and ascends or descends as the wire rope is wound. 15 (a) and 15 (b), the motor 7 is disposed on one side of the wire rope winding portion, and the two electromagnetic brakes 3 and 5 are disposed on the other side, with an emphasis on balance in the horizontal plane. .

  16 (a) and 16 (b) are winches similar to FIGS. 15 (a) and 15 (b), but the main brake 3 and the auxiliary brake 5 are arranged separately on the left and right. For this reason, the heat generated by the main brake is not easily transmitted to the auxiliary brake. In addition, the volume inside the gondola can be increased by arranging the auxiliary brake 5 so as to face the inside of the gondola.

  FIGS. 17A and 17B and FIGS. 18A and 18B are views showing winches in which the rotation axis of the motor 7 is arranged in parallel with the direction of the wire rope. 17A and 17B, the main brake and the auxiliary brake are arranged so as to be vertically divided. For this reason, when the protrusion of the motor becomes a problem in the winches of FIGS. 15 and 16, the worm reducer 8 changes the direction of power transmission by 90 ° and the motor can be mounted so as to be parallel to the wire rope. it can. Therefore, the protrusion of the motor can be solved.

  In the structure shown in FIGS. 17A and 17B, the heat of the main brake is not easily transmitted to the auxiliary brake by attaching the main brake and the auxiliary brake separately. Even if the shaft of the main brake is broken, the load can be held because the shaft of the auxiliary brake is coupled.

  Further, as shown in FIG. 18, when the main brake and the auxiliary brake are attached at the same place, there is an advantage that the size can be made compact.

  Although the embodiments of the present invention have been described above, the embodiments of the present invention disclosed above are merely examples, and the scope of the present invention is not limited to these embodiments. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

It is a figure which shows the winch in embodiment of this invention. It is a figure which shows the electromagnetic brake used for the winch of FIG. It is a circuit diagram of the part containing the main brake and auxiliary brake of the winch shown in FIG. It is a figure which shows the difference in the release time by the power supply collection site | parts of an electromagnetic brake. It is a flowchart of winch operation in the case of ascending operation. It is a flowchart of winch operation in the case of descent operation. It is a flowchart of the operation confirmation method of an auxiliary brake. It is a circuit diagram of a portion including a main brake and an auxiliary brake in another embodiment of the present invention. It is a figure which shows the difference in the release time by the power supply collection site | parts of an electromagnetic brake. FIG. 6 is a circuit diagram of a portion including a main brake and an auxiliary brake in still another embodiment of the present invention. It is a figure which shows the aspect by which the winch of an example of this invention is used for the gondola. It is a figure which shows the aspect in which the winch of an example of this invention is used for raising / lowering a load. It is a figure which shows the aspect in which the winch of an example of this invention is used for raising / lowering a load. It is a figure which shows the winch of an example of this invention, (a) is a front view, (b) is a fragmentary sectional view. It is a figure which shows the winch of the other example of this invention, (a) is a front view, (b) is a fragmentary sectional view. It is a figure which shows the winch of another example of this invention, (a) is a front view, (b) is a fragmentary sectional view. It is a figure which shows the winch of the example different from the above of this invention, (a) is a front view, (b) is a fragmentary sectional view. It is a figure which shows the winch of another example from the above of this invention, (a) is a front view, (b) is a fragmentary sectional view.

Explanation of symbols

  1 winding part, 3 main brake (first electromagnetic brake), 5 auxiliary brake (second electromagnetic brake), 7 electric motor (motor), 8 speed reducer, 9 hanging wire rope, 10 winch, 11 main brake side AC / DC converter, 13 AC / DC converter on auxiliary brake side, 15 Power supply switch to motor, 17, 19 Relay switch, 21 Armature, 23 Brake disc, 25 Brake spring, 27 Coil, 29 Field core, 31 Side plate, 33 wire rope, 35 gondola, 37 control panel.

Claims (2)

A winch that winds a wire rope around a winding part and rotates the winding part by an electric motor to move the load up and down,
A first electromagnetic brake which is in a released state with respect to the rotational motion of the winding portion when the motor is driven and enters an operation of applying a braking force to the winding portion when the input to the motor is stopped; When,
In addition to the first electromagnetic brake, when the electric motor is driven, it is in a released state with respect to the rotational movement of the winding portion, and when the input to the electric motor is stopped, the braking force is applied to the winding portion. A winch comprising a second electromagnetic brake that enters an action of exerting a force.   In the second electromagnetic brake, when the input to the electric motor is stopped, the timing of applying a braking force to the winding portion is set to the winding portion when the input to the electric motor is stopped in the first electromagnetic brake. The winch according to claim 1, which is later than a timing at which a braking force is exerted on the winch.

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