JPH08259185A - Electric hoist - Google Patents

Abstract

PURPOSE: To provide an electric hoist devised to endure high frequency use and to improve working performance. CONSTITUTION: A wire drum 2 is supported in the inside of a drum case 7 through a bearing 58 free to rotate. A rotor shaft 10 of a main motor M1 for low speed is spline connected to one end 3a of a connecting shaft 3 inserted into this wire drum 2. Additionally, a rotor shaft 50 of an auxiliary motor M2 for high speed is spline connected to the other end 3b of the connecting shaft 3. Furthermore, fan members 52, 23 are installed on each of the auxiliary motor M2 and the main motor M1, an air intake port 28 and an air exhaust port 29 are provided on an outline of the main motor M1, and an air intake port 55 and an air exhaust port 56 are provided on a motor frame 47 of the auxiliary motor M2. One of the motors is cooled at the time when either of the motors is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric hoist capable of improving work efficiency under light load and capable of withstanding frequent use.

[0002]

2. Description of the Related Art Conventionally, as an electric hoist for selectively changing the number of poles for low-speed rotation or high-speed rotation, an invention as disclosed in, for example, Japanese Utility Model Publication 5-12232 is proposed. is there. This invention detects the load applied to an electric hoist and converts the number of poles of one pole number conversion type motor to a low speed pole (8 poles) at heavy load and a high speed pole (4 poles) at light load. ) To control the speed of the electric hoist.

[0003]

In such a conventional electric hoist, there is only one hoisting motor regardless of heavy load or light load. There is a problem that the motor is burned or the bearing is burned due to the heat generated from the device.

The present invention has been made in order to solve such a problem. When a light load is applied, an auxiliary motor having a high speed pole is driven, and at this time, the main motor is rotated by the auxiliary motor to self-cool and a heavy load is applied. At times, the main motor of the low speed pole is driven, and at this time, the auxiliary motor is rotated by the main motor to self-cool so that it can withstand high frequency use, and to provide an electric hoist that improves work efficiency. To do.

[0005]

According to a first aspect of the invention, one end of a connecting shaft that rotatably supports a wire drum inside a drum case via a bearing and is inserted in the axial direction of the wire drum is provided. A rotor shaft of a low-speed main motor is coupled to, and a rotor shaft of a high-speed auxiliary motor is coupled to the other end, and a fan member is provided for each of the auxiliary motor and the main motor. The casing is provided with an intake hole and an exhaust hole.

According to a second aspect of the present invention, the casing of the main motor is formed by connecting a drum side motor frame part of which is inside the wire drum and a brake side motor frame connected to the drum side motor frame. The drum side motor frame is provided with an intake hole for introducing air in the vicinity of the rotor shaft of the main motor, the brake side motor frame is provided with an exhaust hole, and the rotor shaft is provided in the vicinity of the exhaust hole. It is characterized in that a mounted fan member is provided.

According to a third aspect of the present invention, an intake hole is provided in the casing of the auxiliary motor near the rotor shaft, and
An exhaust hole is provided near a connecting portion of a gear case accommodating the speed reducer, and a fan member is attached to a rotor shaft of the auxiliary motor.

According to a fourth aspect of the present invention, the low-speed main motor coupled to one end of the connecting shaft of the wire drum is configured to operate under heavy load, and the high-speed main motor coupled to the other end of the connecting shaft. The auxiliary motor for vehicle is characterized in that it is configured to operate at light load or no load.

[0009]

According to the first aspect of the present invention, when the load is heavy, the main motor (low speed pole) is energized to drive the wire drum at a low speed. At this time, the auxiliary motor (high-speed pole) is caused to follow the main motor, the fan member is rotated, and the auxiliary motor is self-cooled. When the load is light, the auxiliary motor is energized to drive the wire drum at high speed. At this time, the main motor is caused to follow the auxiliary motor, the fan member is rotated, and the main motor is self-cooled.

According to the second aspect of the present invention, the fan member provided in the vicinity of the exhaust hole of the main motor is rotated by the auxiliary motor rotated at the time of light load, and air is sucked into the casing of the main motor to drive the motor. Cool the inside of the frame.
Air is taken in through an intake hole formed near the rotor shaft of the drum-side motor frame and formed in the inside of the wire drum, and is exhausted through an exhaust hole provided in the brake-side motor frame.

According to the third aspect of the present invention, the fan member provided on the rotor shaft of the auxiliary motor is rotated by the main motor rotated at the time of heavy load, and the air is sucked into the casing through the intake hole to move the inside of the motor frame. Allow to cool. Air is taken in through an intake hole near the rotor shaft of the casing, and is exhausted through an exhaust hole provided near a connection portion with a gear case housing the reduction gear.

In a fourth aspect of the present invention, a low speed main motor coupled to one end of the connecting shaft of the wire drum is connected so as to operate under heavy load, and the wire drum is rotated at low speed during heavy load. And slowly hoist or unwind the load. In addition, by connecting a high speed auxiliary motor connected to the other end of the connecting shaft so that it will operate at light load or no load, rotate the wire drum at high speed at low load or no load to Wind up or down quickly.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of the electric hoist 1 of the present invention, and FIG. 2 is a schematic view of the electric hoist 1. As shown in the figure, the drive section of the electric hoist 1 is roughly composed of a main motor M1 and an auxiliary motor M2, and a brake device B is provided on the main motor M1 side.
Are integrally connected, and a speed reducer G is connected to the auxiliary motor M2 side. The main motor M1, the speed reducer G, and the auxiliary motor M2 are integrally connected by a connecting shaft 3 that passes through the shaft core of the wire drum 2.

Individual members constituting the electric hoist 1 will be described. First, a low-speed (low-speed pole, for example, 4-pole) main motor M1 provided on one side of the wire drum 2
The brake device B will be described. The casing of the main motor M1 is roughly constituted by a drum side motor frame 4 partly inside the side surface of the wire drum 2 and a brake side motor frame 5 located on the brake device B side. Flange portion 4a of the drum side motor frame 4
And one side flange portion 5a of the brake side motor frame 5
Is integrally fixed to the ring member 8 of the drum case 7 that covers the wire drum 2 by the mounting bolt 6.

A stator core 9 is fixed inside the casing of the main motor M1 as described above.
A rotor shaft 10 rotatably supported by bearings described later and a rotor core 11 attached to the outer periphery of the rotor shaft 10 are housed inside the. Reference numeral 12 is a stator coil.

The rotor shaft 10 has an end 10 on the wire drum 2 side.
a is the bracket part at the center of the drum-side motor frame 4
It is rotatably supported by a bearing 14 provided at 13, and an end 10b on the side of the brake device B is rotatably supported by a bearing 16 provided at a bracket portion 15 at the center of the brake side motor frame 5. There is.

A brake case 17 of the brake device B is attached to the brake-side motor frame 5. That is, the flange portion 17a of the brake case 17 and the other flange portion 5b of the brake side motor frame 5 are
Four screw guide rods 18 at both ends and nuts 19 screwed together
Are fixed together by and.

Next, the brake mechanism of the brake device B will be described. Main motor M facing the brake case 17
The end portion of the first rotor shaft 10 is formed in a slightly tapered shape, and a brake wheel 22 is integrally fixed to the rotor shaft 10 via a key 20 and a fastening nut 21. This brake wheel 22
As shown in FIG. 3, a plurality of fan members 23 are integrally formed so as to radially project.

A brake lining 24 is fitted on the fan member 23. Therefore, the brake lining 24 can rotate together with the rotor shaft 10 and can slide a small distance in the axial direction.

A fixed iron core 25 is provided on the circular bracket portion 17b at the center of the wall of the brake case 17.
An iron brake shoe 26 is provided between the fixed iron core 25 and the brake wheel 22 of the rotor shaft 10.
The vicinity of the outer peripheral portion of the brake shoe 26 faces the brake lining 24.

Further, notches (not shown) are formed at four positions on the outer edge of the brake shoe 26, and the notches are engaged with the guide rod 18 with the both ends threaded (FIG. 1).
(See above brake shoe 26). Therefore, although the rotation of the brake shoe 26 is restricted, the brake shoe 26 can slide in the axial direction by a minute distance d.

In addition, the brake shoe 26 and the brake case
A spring 27 is interposed between the spring 17 and the spring 17. The spring 27 constantly urges the brake shoe 26 toward the brake lining 24 side so that the brake lining 24 is pressed and sandwiched between the brake shoe 26 and the other flange portion 5b of the brake side motor frame 5. .

Drum side motor frame 4 of the main motor M1
In the vicinity of the bearing 14 that supports the end portion 10a of the rotor shaft 10, a required number of intake holes 28 for introducing air are provided. Further, a required number of exhaust holes 29 for exhausting the air in the casing of the main motor M1 are provided at the contact portion between the flange portion 17a of the brake case 17 and the other flange portion 5b of the brake side motor frame 5. ing.

Further, an air circulation groove 30 is provided in parallel with the rotor shaft 10 in a portion where the stator core 9 is fixed in the casing of the main motor M1. Further, a required number of air circulation holes 31 through which air flows from the inside of the casing of the main motor M1 to the inside of the brake casing are provided in the wall portion of the brake side motor frame 5 near the fan member 23. In addition, the brake lining of the brake shoe 26
On the brake lining 24 side of the other side flange portion 5b of the 24 side and the brake side motor frame 5, a required number of air circulation grooves 32 are radially formed.

The air flow groove 32 is formed in a concave shape so as not to interfere with the rotating brake lining 24. A series of air flows generated by the rotation of the fan member 23 deprives Joule heat generated from the main motor M1 and frictional heat generated from the brake device B.

Next, the speed reducer G provided on the other side of the wire drum 2 and the auxiliary motor M2 for high speed (high speed pole, for example, 2 poles) will be described. The speed reducer G has a casing composed of a gear case 33 located on the side of the auxiliary motor M2 and a gear case cover 34 located on the side of the wire drum 2 in which a plurality of reduction gears 35 are housed.
The rotations of the auxiliary motor M2 and the main motor M1 are reduced to a desired reduction ratio.

The gear case cover 34 and the gear case 33 of the speed reducer G are integrally mounted and fixed to the ring member 8 of the drum case 7 by mounting bolts 36. The speed reducer G is provided with an input shaft 37.
The bearing 37 is rotatably supported by a bearing 38 attached to the center of the gear case cover 34 and the gear case 33.

A first gear 39 is engraved on the peripheral surface of the input shaft 37 on the side of the auxiliary motor M2. The first gear 39 has a second gear.
40 meshed. A third gear 41, which is formed coaxially with the second gear 40, meshes with a fourth gear 42 rotatably provided outside the input shaft 37. Further, the fifth gear 43 coaxially provided on the fourth gear 42 includes a second gear 40 and a third gear 40.
A sixth gear 44 provided coaxially with the gear 41 meshes.

The final gear 45 provided coaxially with the sixth gear 44 meshes with the internal gear 46 of the wire drum 2. As a result, the rotational forces of the auxiliary motor M2 and the main motor M1 are transmitted to the wire drum 2. In addition, although the reduction gear 35 is set to 8 stages for deceleration, the deceleration may be set for an appropriate number of stages.

A motor frame 47, which is a casing of the auxiliary motor M2, is connected to the gear case 33 of the speed reducer G. The motor frame 47 is attached by fixing the flange portion 47a to the gear case 33 with bolts 48. Inside the motor frame 47 is a stator core.
A rotor shaft 50 and a rotor core 51 mounted on the outer periphery thereof are housed inside the rotor shaft 50.

A fan member 52 for introducing and discharging air into the motor frame 47 of the auxiliary motor M2 is mounted on the outer periphery of the rotor shaft 50 on the speed reducer G side. Code 53
Shown by is a stator coil.

The rotor shaft 50 is rotatably supported by bearings 54 provided on the gear case 33 and the motor frame 47. The rotor shaft 50 of the auxiliary motor M2 and the input shaft 37 of the speed reducer G are connected by spline fitting.

A fan member provided on the auxiliary motor M2
A required number of intake holes 55 for introducing air are provided near the bearing 54 supporting the rotor shaft 50 on the wall portion of the motor frame 47 on the side opposite to 52. Further, the motor frame 47 on the fan member 52 side is provided with an exhaust hole 56 for exhausting air. Reference numeral 57 is a motor frame of the auxiliary motor M2.
In the part of 47 that fixes stator core 49,
The air circulation groove is provided in parallel with 50.

Finally, the wire drum 2 provided at the center will be described. The wire drum 2 is disposed inside the drum case 7 described above, and one side 2a of the wire drum 2 is attached to a bracket portion 4b at the center of the drum side motor frame 4,
On the other hand, 2b is a bracket portion 34 at the center of the gear case cover 34.
It is rotatably supported by bearings 58 attached to b.

As shown in FIG. 2, a wire rope 59 having one end fixed to the outer peripheral surface is wound around the outer peripheral portion of the wire drum 2. The other end of the wire rope 59 is connected to the drum case 7 via the hook block 60 and the load detection mechanism LC.
It is stuck to.

The load detection mechanism LC is composed of, for example, a load limiter and the like, and the switch mechanism inside thereof has the light load switch 61 on the H side at the time of light load or no load, and the heavy load switch 62 at the time of heavy load. It is composed of contacts for on / off control such as the L side. In FIG. 1, reference numeral 63 is a wire holding plate. Further, reference numeral 64 is a small screw for fixing the wire pressing plate.

A ventilation groove 65 for introducing outside air into the casing of the main motor M1 is provided between the end surface of the wire drum 2 on the main motor M1 side and the flange portion 4a of the drum side motor frame 4. . Air is introduced into the drum case 7 through an opening through which the wire rope 59 is inserted.

Further, one side 3a of the connecting shaft 3 disposed through the wire drum 2 is spline-fitted to the rotor shaft 10 of the main motor M1, and the other side 3b is an input shaft of the speed reducer G. 37
It is fitted with a spline. By this, the main motor M
The rotor shaft 10 of 1 and the rotor shaft 50 of the auxiliary motor M2 are connected via the connecting shaft 3 and the input shaft 37.

Next, the control circuit of the electric hoist 1 shown in FIGS. 1 and 2 will be described with reference to FIG. This circuit is a simplified description of the three-phase circuit. To the three-phase power supply terminal 66, the ascending coil 69 of the magnet switch is connected via the ascending switch 68 of the push button switch 67, and the descending coil 71 of the magnet switch is connected via the descending switch 70. There is.

The light load switch 61 of the load detection mechanism LC
The light load coil 72 of the magnet switch is connected via the, and the heavy load coil 73 of the magnet switch is connected via the heavy load switch 62.

Further, the heavy load coil 73 is excited through the anti-parallel connection circuit of the main contact 74 which is closed by exciting the ascending coil 69 and the main contact 75 which is closed by exciting the descending coil 71. Each of the contacts 76 closed by and the contact 77 closed by the excitation of the light load coil 72, and the brake device B are connected in parallel.

The main motor M1 is connected to the contact 76,
An auxiliary motor M2 is connected to 77. When the brake device B is energized, the brake shoe 26 is attracted to the fixed iron core 25, the brake shoe 26 and the brake lining 24 are separated, and the brake is released.
When the energization is released, the spring 27 produces a braking force.

The operation of the electric hoist 1 thus constructed will be described. Now, assuming that the worker presses the ascending switch 68 of the push button switch 67, the ascending coil 69 is excited to close the main contact 74 and release the brake device B. When the load detection mechanism LC detects the load state applied to the hook block 60 and the heavy load switch 62 of the load detection mechanism LC is in the closed state (L side), the heavy load coil 73 is excited. Contact 76 closes,
As a result, the main motor M1 is energized and the wire drum 2
Is rotated at a low speed, and the hook block 60 is wound at a low speed and with a large force.

Next, the push button switch 67 descending switch 70
When is pressed, the descending coil 71 is excited, so the main contact 75
Is closed and the heavy load switch 62 is in the closed state (L side) in the same manner as described above, the heavy load coil 73 is excited, and the contact 76 is closed.
The main motor M1 connected via 76 rotates in the opposite direction. This causes the hook block 60 to be lowered at a low speed.

The rotation of the main motor M1 is transmitted from the rotor shaft 10 through the connecting shaft 3 to the input shaft 37 of the speed reducer G,
The wire drum 2 is driven by being transmitted from the reduction gear 35 to the internal gear 46 of the wire drum 2. The rotation of the main motor M1 is also transmitted to the rotor shaft 50 of the auxiliary motor M2 via the input shaft 37 of the reduction gear G. Therefore, when the wire drum 2 is rotating, the rotor shaft 50 of the auxiliary motor M2 rotates following the main motor M1 and the fan member 52 mounted on the rotor shaft 50 rotates.

As a result, air is sucked into the motor frame 47 of the auxiliary motor M2 from the air intake hole 55, and the air is discharged from the exhaust hole 56 through the air circulation groove 57 as shown by the arrow. This air circulation cools the inside of the motor frame 47 of the auxiliary motor M2, in particular, the stator coil 53 and the bearing 54 of the rotor shaft 50.

When no load is applied to the hook block 60, the light load switch 61 of the load detection mechanism LC is closed (H side), whereby the light load coil 72 is excited and the contact 77 is closed. . Then, when the ascending switch 68 of the push button switch 67 is pressed, the ascending coil 69 is excited to close the main contact 74. As a result, the brake device B is released and the auxiliary motor M
2 is energized, the wire drum 2 rotates at high speed, and the hook block 60 is wound up at high speed. When the descending switch 70 is pressed, the hook block 60 is unwound at high speed.

The rotational force of the rotor shaft 50 of the auxiliary motor M2 is transmitted to the input shaft 37 and the reduction gear 35 of the reduction gear G to drive the wire drum 2 in rotation, and the rotor shaft of the main motor M1 is rotated via the connecting shaft 3. Transmitted to 10. Therefore, the main motor M1 rotates following the auxiliary motor M2, and the rotor shaft 10
The fan member 23 attached to the fan rotates. As a result, air is sucked into the casing of the main motor M1 through the intake hole 28, and the air circulation groove 30 and the air circulation hole 3 are indicated by arrows.
1. A series of air flows discharged from the exhaust holes 29 through the air circulation groove 32. Due to this air flow, the inside of the casing of the main motor M1, in particular, the stator coil 12 and the bearings 14 and 16 of the rotor shaft 10 are air-cooled, and the brake device B is also air-cooled.

[0049]

As described above, according to the present invention, the main motor and the auxiliary motor are selected and driven according to the load condition.
Moreover, when the motor on one side is being driven, the motor on the non-driving side is caused to rotate following the motor being driven, and the fan member provided for each motor is used for self-cooling. Therefore, the temperature rise of the motor and the bearing is suppressed, and it is possible to endure high frequency use.

In the electric hoist, the light load operation occupies about 70% of the total operation time. Since the high speed auxiliary motor is driven during the light load operation, the work efficiency can be improved. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an electric hoist showing an embodiment of the present invention.

FIG. 2 is a diagram schematically showing that of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a circuit diagram for operating the electric hoist of FIG. 1.

[Explanation of symbols]

 1 Electric Hoist 2 Wire Drum 3 Connection Shaft 4 Drum Side Motor Frame 5 Brake Side Motor Frame 7 Drum Case 10 Rotor Shaft 22 Brake Wheel 23 Fan Member 28 Intake Hole 29 Exhaust Hole 30 Air Circulation Groove 31 Air Circulation Hole 32 Air Circulation Groove 33 Gear case 34 Gear case cover 47 Motor frame 50 Rotor shaft 52 Fan member 55 Intake hole 56 Exhaust hole 57 Air circulation groove 58 Bearing B Brake device G Reduction gear M1 Main motor M2 Auxiliary motor

Claims (4)

[Claims] 1. A wire drum is rotatably supported inside a drum case via a bearing, and a rotor shaft of a low-speed main motor is connected to one end of a connecting shaft inserted in the axial direction of the wire drum. , A rotor shaft of a high-speed auxiliary motor is coupled to the other end, fan members are provided in each of the auxiliary motor and the main motor, and intake holes and exhaust holes are provided in casings of the main motor and the auxiliary motor. And an electric hoist. 2. The main motor casing is formed by combining a drum side motor frame, a portion of which is inside the wire drum, and a brake side motor frame connected to the drum side motor frame. An intake hole for introducing air is provided in the frame near the rotor shaft of the main motor, an exhaust hole is provided in the brake-side motor frame, and a fan member mounted on the rotor shaft is provided near the exhaust hole. The electric hoist according to claim 1, wherein the electric hoist is formed. 3. An auxiliary motor casing is provided with an intake hole near a rotor shaft, an exhaust hole is provided near a connecting portion of a gear case accommodating a speed reducer, and a fan member is attached to a rotor shaft of the auxiliary motor. The electric hoist according to claim 1, wherein: 4. A low-speed main motor connected to one end of a wire drum connecting shaft is configured to operate at a heavy load, and a high-speed auxiliary motor connected to the other end of the connecting shaft has a light load. The electric hoist according to claim 1, wherein the electric hoist is configured to operate at a load or without a load.