JP2003222170A - Wet type multiple disk brake device, wet type multiple disk clutch device, and winding apparatus for crane therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a position gap of a spring provided between disks of a wet type multiple disk brake. <P>SOLUTION: Inner disks 12 are movably engaged with a carrier shaft 54 to an axial direction, and a coil spring 18 is provided between the inner disks 12. Outer disks 13 are provided between the inner disks 12. Outer disks 13 are movably engaged with a brake case 11 to an axial direction, and a coil spring 19 is provided between the outer disks 13. Rods 41 and 42 are pierced into the disks 12 and 13, respectively. The rods 41 and 42 pierces through the inside of the coil springs 18 and 19, and positions of the coil springs 18 and 19 are fixed by the rods 41 and 42. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet multi-plate brake device for exerting a braking force by pressing a plurality of friction plates engaged with a rotating body and a plurality of friction plates engaged with a case, and a clutch force. The present invention relates to a wet multi-plate clutch device, and a hoisting device for a crane including the brake device and the clutch device.

[0002]

2. Description of the Related Art A brake device of this type is disclosed in, for example, Japanese Patent Laid-Open No.
No. 000-16771. According to this, the multiple discs (inner discs) engaged with the carrier shaft and the multiple discs (outer discs) engaged with the brake case are alternately arranged in the brake case, and the inner discs and outer discs are A spring (wave spring) is inserted between the disks. And
Brake discs are placed beside these discs.
When the brake disc is pushed, the inner disc and the outer disc are brought into close contact with each other against the spring force, whereby the rotation of the carrier shaft is prohibited and the brake is activated. On the other hand, when the pushing motion of the brake disc is released,
The inner disc and the outer disc are pulled apart from each other by a spring force, whereby the rotation of the carrier shaft is allowed and the brake is released.

[0003]

In the device described in the above publication, when the position of the spring interposed between the discs is displaced, the spring force acting between the discs varies and the brake device operates properly. It may not be released. In particular, since the spring is built in the brake case, it is difficult to visually check the spring position from the outside, and it is necessary to reliably prevent displacement of the spring when assembling the brake device.

An object of the present invention relates to a wet multi-disc brake device capable of reliably preventing displacement of a spring, a wet multi-disc clutch device, and a hoisting device for a crane equipped with the brake device and the clutch device.

[0005]

(1) A wet multi-plate brake device according to a first aspect of the invention includes a plurality of first friction plates axially movably engaged with an outer peripheral surface of a rotating body, A plurality of second friction plates axially movably engaged with the inner peripheral surface of the case that accommodates the rotating body, and arranged alternately with the first friction plates in the axial direction; Plate and the second friction plate are pushed in the axial direction to exert a pressure contact force on the first friction plate and the second friction plate, and a pressure contact force for driving the push member to adjust the pressure contact force. The adjusting means is interposed between the first friction plates and between the second friction plates, and the first friction plates are connected to each other and the second friction plates are interposed.
And the spring fixing means for fixing the coil springs at predetermined positions with respect to the first friction plate and the second friction plate. To achieve. (2) According to the invention of claim 2, in the wet multi-plate brake device according to claim 1, the spring fixing means axially penetrates the first friction plate and the second friction plate, respectively, and a coil spring. It has a rod member penetrating the inside of. (3) The invention of claim 3 is the wet multi-plate brake device according to claim 1, wherein the spring fixing means corresponds to the outer peripheral shape of the coil spring on the surfaces of the first friction plate and the second friction plate, respectively. The coil spring is provided in this recess. (4) According to the invention of claim 4, in the wet multi-plate brake device according to claim 1, the spring fixing means has an inner peripheral shape of a coil spring on the surfaces of the first friction plate and the second friction plate, respectively. The coil spring has a correspondingly formed protrusion, and the coil spring is provided on this protrusion. (5) According to the invention of claim 5, in the wet multi-plate brake device according to claim 1, the spring fixing means are respectively interposed between the first friction plates and move axially to the outer peripheral surface of the rotating body. A first ring member that is movably engaged and a second ring member that is interposed between the second friction plates and that is axially movably engaged with the inner peripheral surface of the case. , The coil spring interposed between the first friction plates penetrates the first ring member, and the coil spring interposed between the second friction plates penetrates the second ring member. It is provided. (6) The wet multi-plate clutch device according to the invention of claim 6 is
The first friction plate according to any one of claims 1 to 5, a second friction plate, a pushing member, a pressure adjusting means, a coil spring, and a spring fixing means, and the first friction plate. Friction plate and second
The above-mentioned object is achieved by transmitting / non-transmitting the power of the rotating body to the case via the friction plate. (7) A hoisting device for a crane according to the invention of claim 7 achieves the above-mentioned object by including the wet multi-plate brake device according to any one of claims 1 to 5. (8) The hoisting device for a crane according to the invention of claim 8 achieves the above-mentioned object by including the wet multi-plate clutch device of claim 6.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment Hereinafter, a first embodiment of a wet multi-plate brake device according to the present invention will be described with reference to FIGS. 1 to 5 and 12. FIG. 1 is a hydraulic circuit diagram of a winch having a wet multi-plate brake device according to an embodiment of the present invention.
[Fig. 3] is a side view of a crane equipped with this brake device. As shown in FIG. 12, the crane is a traveling body 101.
And a revolving revolving structure 10 mounted on the traveling structure 101.
2 and the boom 10 supported by the revolving structure 102 so as to be able to rise and fall.
3 and 3. The winch drum 1 is mounted on the revolving structure 102, and the wire rope 1 is driven by driving the winch drum 1.
04 is hoisted or hoisted down, and the hanging load 106 is hoisted by the hook 105 connected to the wire rope 104. An undulating drum 107 is mounted on the revolving structure 102, and the undulating rope 10 is driven by driving the undulating drum 107.
8 is wound up or down, and the boom 103 is undulated.

As shown in FIG. 1, a winch includes a winch drum 1 and a hydraulic motor 2 for driving the winch drum 1.
And a hydraulic pump 3 that supplies driving pressure oil to the hydraulic motor 2.
A directional control valve 4 for controlling the flow of pressure oil from the hydraulic pump 3 to the hydraulic motor 2, and a planetary speed reduction mechanism 5 for transmitting or not transmitting the driving force of the hydraulic motor 2 to the winch drum 1.
A wet multi-plate type brake device 10 that controls the drive of the winch drum 1 is provided.

The output shaft 2a of the hydraulic motor 2 is connected to the sun gear 51 of the planetary reduction mechanism 5. A planetary gear 52 is meshed with the sun gear 51, and the planetary gear 52 is provided with a ring gear 53 provided inside the winch drum 1.
Are meshed. Planetary gear 52 is carrier shaft 5
4, the carrier shaft 54 is supported by the brake case 1
1 penetrates the side wall and reaches the inside of the case 11.

FIG. 2 is a sectional view showing the structure of the brake device 10, and FIG. 3 is an enlarged view of the main parts of FIG. 2 and 3 show the released state of the brake device 10. Figures 2 and 3
As shown in FIG. 5, a plurality of inner discs 12 are engaged with the carrier shaft 54 by spline coupling so as to be movable in the axial direction, and the inner disc 12 is rotatable integrally with the carrier shaft 54. A plurality of outer disks 13 are engaged with the inner peripheral surface of the brake case 11 by spline coupling so as to be movable in the axial direction. Outer disk 1
3 and the inner disc 12 are arranged alternately in the axial direction. An outer disc 13 is arranged on the outermost side in the axial direction, and the outermost outer disc 13 is in contact with the inner wall surface 11d of the brake case and the end surface 14a of the brake disc 14, respectively.

A brake disc 14 is disposed on the side of the discs 12 and 13, and the brake disc 14 is slidable in the brake case 11 in the axial direction. An oil chamber 15a is provided between the brake disc 14 and the brake case side wall 11a, and the oil chamber 15a communicates with the pipe line 31 (see FIG. 1) through the opening 15b. A spring seat 16 is fixed to the inner peripheral surface of the brake case 11, and the spring seat 1
A spring 17 is interposed between 6 and the brake disc 14. The hydraulic pressure in the oil chamber 15a and the biasing force of the spring 17 act mainly on the brake disc 14, and the brake disc 14 moves according to the difference between the two forces. The brake case 11 is provided with an oil supply hole 11b and an oil discharge hole 11c, and cooling oil flows through the case 11 via the oil supply hole 11b and the oil discharge hole 11c.

Between the outer discs 13, the coil springs 1 are arranged on the outer diameter side of the outer peripheral surface of the inner disc 12.
8 is interposed. Coil springs 19 are provided between the inner discs 12 on the inner diameter side of the inner peripheral surface of the outer disc 13. On the outer peripheral surface of the carrier shaft 54, a spring seat 21 is detachably fixed to the outer side of the inner disc 12 in the axial direction, and a spring 19 is also interposed between the spring seat 21 and the innermost disc 12 in the axial direction. ing.

The coil springs 18 and 19 have the same shape and are arranged at equal intervals circumferentially (see FIG. 5). The coil springs 18 and 19 exert a separating force between the disks 12 and 13 to separate the disks 12 and 13. At this time, the positions of the side end surface 11d of the brake case 11, the side end surface 14a of the brake disk 14, and the spring seat 21 are set so that the gaps between the inner disc 12 and the outer disc 13 are all equal as shown in the figure. Has been adjusted. The spring force of the coil springs 18 and 19 is set to a value sufficient to separate the disks 12 and 13 in the close contact state. The mounting structure of the coil springs 18 and 19 will be described later.

As shown in FIG. 1, the oil chamber 15a of the hydraulic cylinder 15 has a hydraulic pressure source (for example, via a conduit 31, a pressure reducing valve 32 and an electromagnetic switching valve 33 or via a conduit 31 and an electromagnetic switching valve 33). Hydraulic pump) 34. The solenoid of the electromagnetic switching valve 33 is connected to the free fall switch 36. The free fall switch 36 is switched by operation in the driver's cab, and when the free fall switch 36 is turned on, the solenoid valve 33 is switched to position b. As a result, the pressure oil from the hydraulic pressure source 34 is supplied to the pressure reducing valve 32. When the free fall switch 36 is off,
The electromagnetic switching valve 33 is switched to the position A, and the pressure oil from the hydraulic pressure source 34 is directly supplied to the oil chamber 15a.

The pressure reducing valve 32 is a variable pressure reducing valve, and the degree of pressure reduction is changed according to the depression amount of the brake pedal 35. That is, the degree of pressure reduction is maximum when the pedal is not operated (the secondary pressure is the tank pressure), the degree of pressure reduction decreases (the secondary pressure increases) as the pedal stroke increases, and the degree of pressure reduction increases when the pedal 35 is fully depressed. Is minimum (secondary pressure is maximum). The figure shows the pedal non-operation state.

When a maximum secondary pressure acts on the oil chamber 15a,
The hydraulic cylinder 15 extends against the biasing force of the spring 17,
The brake disc 14 is pushed toward the discs 12 and 13. As a result, the inner disc 12 and the outer disc 13 are pressed against the separating force of the coil springs 18 and 19, and the inner disc 12 and the outer disc 13 are brought into close contact with each other to be in the brake operating state. On the other hand, when the oil chamber 15a is under tank pressure, the hydraulic cylinder 15 contracts due to the urging force of the spring 17, and the pressure contact force from the brake disc 14 is released. As a result, the inner disc 12 and the outer disc 13 are separated by the separating force of the coil springs 18 and 19, and the brake is released.

Here, the mounting structure of the coil springs 18 and 19 will be described. FIG. 5 is a perspective view of the disks 12 and 13. Through holes 12 are provided in the disks 12 and 13, respectively.
a, 13a are provided, and all inner discs 12 or outer discs 13 are provided through the through holes 12a, 13a.
Rods 41 and 42 pass through the respective parts. Each rod 41, 42 passes through the inside of a coil spring 18, 19 respectively, whereby the spring 18,
The position of 19 is fixed. As shown in FIG. 3, the rod 4
One end surface of No. 1 is in contact with the side end surface 11a of the brake case 11, and the other end surface is in contact with the spring seat 16. Rod 42
Both end surfaces of the are contacted with the spring seat 21, respectively.

The brake device 10 is assembled as follows. First, the brake case 11 is provided in an upright state, for example, so that the carrier shaft 54 is vertically downward. In this state, the outer disk 13 is engaged with the spline on the inner circumference of the brake case, the inner disk 12 is engaged with the spline on the outer circumference of the carrier shaft, and the disks 12, 13 are alternately stacked. At this time, the coil springs 18 and 19 are interposed between the disks 12 and 13, respectively.
The rods 41 and 42 are inserted into the respective coil springs 18 and 19 through the coil 13. This fixes the spring position. Next, the spring seats 16 and 21 are fixed to the brake case 11 and the carrier shaft 54, respectively, and the axial positions of the rods 41 and 42 are restricted. The rods 41 and 42 penetrate through the through holes 12a and 13a provided in the disks 12 and 13,
This allows the rods 41,4 to the disks 12,13
Two positions are defined. Subsequently, the spring 17 and the brake disc 14 are set in the case 11, and the case side wall 11a is attached to the brake case 11.

The main operation of the wet multi-plate brake device according to the first embodiment configured as described above will be described. (1) Free fall switch off When the free switch 36 is off, the electromagnetic switching valve 33 is switched to position a. By this switching, the pressure oil from the hydraulic pressure source 34 is transferred to the oil chamber 15 via the electromagnetic switching valve 33 and the conduit 31.
As a result, the brake disc 14 is pushed toward the discs 12 and 13 against the biasing force of the spring 17. As a result, as shown in FIG. 4, the outer disc 13 and the inner disc 12 are pressed against each other against the separating force of the coil springs 18 and 19, and a frictional force acts on the inner disc 12 to rotate the inner disc 12. Is blocked (brake operation).

When the brake device 10 operates, the rotation of the carrier shaft 54 is blocked, and the rotation of the hydraulic motor 2 can be transmitted to the winch drum 1 via the sun gear 51, the planetary gear 52, and the ring gear 53. Here, when the operating lever 6 is hoisted or hoisted to apply pilot pressure oil to the pilot port of the direction switching valve 4, the direction switching valve 4 is switched from the neutral position, and the hydraulic motor 2 is hoisted or wound. Rotate downward. As a result, the winch drum 1 is driven to wind up or wind down, and a hoisting operation of a suspended load can be performed. When the operation lever 6 is returned to the neutral position, the direction switching valve 4 is returned to the neutral position, and the supply of pressure oil from the hydraulic pump 3 to the hydraulic motor 2 is stopped. As a result, the rotation of the hydraulic motor 2 is stopped and the winch drum 1
Stops rotating. The hydraulic motor 2 is provided with a brake device 7 as shown in FIG.
The rotation of the hydraulic motor 2 can also be stopped by.

(2) Free fall switch ON The lever 6 is returned to the neutral position to stop the hydraulic motor 2 or the brake device 7 is operated to stop the hydraulic motor 2 and then the free fall switch 36 is turned on. When turned on, the electromagnetic switching valve 33 is switched to position b.
As a result, the pressure oil from the hydraulic pressure source 34 is supplied to the pressure reducing valve 32 via the electromagnetic switching valve 33, and the secondary pressure according to the operation amount of the brake pedal 35 acts on the oil chamber 15a. When the brake pedal 35 is not operated, the secondary pressure becomes the tank pressure, and the urging force of the spring 17 presses the brake disc 14 against the case side wall 11a. This makes the disc 1
The pressure contact force acting on 2, 13 is removed, and the inner disc 12 becomes rotatable (brake release).

When the brake device 10 is released, the carrier shaft 54 is allowed to rotate, and the winch drum 1 is brought into a free rotation state by the load of the suspended load, so that the suspended load can be free fall. At this time, as shown in FIG. 3, the disc 1 is moved by the separating force of the coil springs 18 and 19.
2, 13 are pulled away from each other. In this case, since the coil springs 18 and 19 are held by the rods 41 and 42,
The gap between the disks 12 and 13 expands and the disks 12 and 1
3 and the coil springs 18 and 19 are in a reduced contact force (even if the contact force is 0), the springs 18 and 1
It is possible to reliably prevent the position shift of 9. As a result, a uniform separating force acts between the disks 12 and 13, and the disks 12 and 13 can be separated at equal intervals. As a result, the drag resistance can be reduced to the maximum and the free fall can be favorably performed even in the case of a light load such as an empty hook.

When the brake pedal 35 is depressed during the free fall, the secondary pressure increases in accordance with the pedal operation amount, and the secondary pressure becomes maximum during the maximum depression operation. As a result, the brake disc 1 is resisted against the biasing force of the spring 17.
4 is pushed and the disks 12 and 13 are pressed against each other.
As a result, the braking force acts on the winch drum 1, and the rotation of the winch drum 1 can be stopped.

As described above, the hydraulic brake device according to this embodiment functions as a brake device for stopping the rotation of the drum 1 at the time of free fall, and
It also functions as a hydraulic clutch device that transmits / non-transmits the rotation of the hydraulic motor 2 to the winch drum 1.

As described above, according to the first embodiment, since the coil springs 18 and 19 are interposed between the disks 12 and 13, respectively, the disk 1 is free-falled.
A separating force can be applied between 2 and 13. Also,
Since the rods 41 and 42 penetrate the discs 12 and 13 and the rods 41 and 42 are inserted into the coil springs 18 and 19, the positions of the coil springs 18 and 19 with respect to the discs 12 and 13 are fixed, and the discs 12 and 13 are fixed. An even spring force can be applied between them. As a result, the disk 12,
The drag resistance acting on 13 can be reduced as much as possible, and the descent of the suspended load at the time of free fall can be improved.

Further, since the coil springs 18 and 19 are interposed between the disks 12 and 13, the disk spacing can be set larger and the degree of freedom in design is improved as compared with the web spring and the disc spring. . Coil spring 1
Since 8 and 19 have high fatigue strength against repeated loading,
The durability and reliability of the device can be secured. Disk 1
The through holes 12a and 13a are opened in the rods 2 and 13 and the rods 41 and 4 are
Since it is only necessary to insert 2, it is applicable to other wet multi-disc brakes.

-Second Embodiment- A second embodiment of the wet multi-plate brake device according to the present invention will be described with reference to FIGS. The second embodiment differs from the first embodiment in that the coil spring 18,
19 is a mounting structure. FIG. 6 is a cross-sectional view showing the structure of the brake device 10 according to the second embodiment, and FIG. 7 is an enlarged view of the main parts of FIG. 6 and 7 show the released state of the brake device 10. The same parts as those in FIG. 3 are designated by the same reference numerals, and the differences will be mainly described below. The spring mounting structure on the inner disk 12 side is the same as the spring mounting structure on the outer disk 13 side, and only one (outer disk side) is shown in FIG. 7.

As shown in FIGS. 6 and 7, in the second embodiment, the coil spring 1 is formed on the surfaces of the disks 12 and 13.
Plural circular spot facing 1 corresponding to the mounting positions of 8 and 19
2b and 13b are formed. This spot facing 12b, 13
The outer peripheral surfaces of the coil springs 18 and 19 are loosely inserted into b, respectively, whereby the coil springs 18 and 19 are fixed.
Thus, in the second embodiment, the disks 12, 13 are
Coil spring 1 on counterbore 12b, 13b formed on the surface of
Since 8 and 19 are fixed, it is not necessary to provide rods 41 and 42, and the positional displacement of the coil springs 18 and 19 can be prevented without increasing the number of parts.

-Third Embodiment- A third embodiment of the wet multi-plate brake device according to the present invention will be described with reference to FIGS. The third embodiment differs from the second embodiment in that the coil spring 18,
19 is a mounting structure. FIG. 8 is a cross-sectional view showing the structure of the brake device 10 according to the third embodiment, and FIG. 9 is an enlarged view of the essential parts of FIG. 8 and 9 show the released state of the brake device 10. The same parts as those in FIGS. 6 and 7 are designated by the same reference numerals, and the differences will be mainly described below. The spring mounting structure on the inner disc 12 side is similar to the spring mounting structure on the outer disc 13 side, and only one (outer disc side) is shown in FIG.

As shown in FIGS. 8 and 9, in the third embodiment, a plurality of cylindrical projections 1 are formed on the surfaces of the disks 12 and 13 corresponding to the mounting positions of the coil springs 18 and 19.
2c and 13c are projected. This convex portion 12c, 13c
The inner peripheral surfaces of the coil springs 18 and 19 are loosely inserted into the coil springs 18 and 19, whereby the coil springs 18 and 19 are fixed. As described above, in the third embodiment, the coil springs 18 and 19 are fixed to the convex portions 12c and 13c formed on the surfaces of the disks 12 and 13, so that the coil springs are thin even when the disks 12 and 13 are thin. 18, 19 can be easily fixed.

-Fourth Embodiment- A fourth embodiment of the wet multi-plate brake device according to the present invention will be described with reference to FIGS. The fourth embodiment differs from the second embodiment in that the springs 18 and 1 are
9 is a mounting structure. FIG. 10 is a sectional view showing the structure of the brake device 10 according to the fourth embodiment.
11 is an enlarged view of a main part of FIG. 10. 10 and 11 show the released state of the brake device 10. The same parts as those in FIGS. 6 and 7 are designated by the same reference numerals, and the differences will be mainly described below. The spring mounting structure on the inner disc 12 side is the same as the spring mounting structure on the outer disc 13 side.
FIG. 11 shows only one of them (outer disc side).

As shown in FIGS. 10 and 11, in the third embodiment, ring members 43 and 44 are arranged between the disks 12 and 13, respectively. The ring member 43 is engaged with the carrier shaft 54 by spline coupling so as to be axially movable, and the ring member 44 is engaged with the brake case 11 by spline coupling so as to be axially movable.
A plurality of through holes 43a, 44a are opened in the ring members 43, 44 corresponding to the mounting positions of the coil springs 18, 19, respectively.
19 is inserted. As a result, the coil spring 1
8 and 19 are fixed. Thus, in the fourth embodiment, the ring members 43, 4 interposed between the disks 12, 13 are provided.
Since the coil springs 18 and 19 are fixed by means of No. 4, the coil springs 18 and 19 can be easily applied to the existing brake device 10 without any additional work on the disks 12 and 13.

Although the above embodiment is applied to the crane, it may be used for another working machine or as a brake device for braking a drive device other than the winch. The hydraulic pressure from the hydraulic pressure source 34 is used as the brake operating pressure, but the hydraulic pressure from the hydraulic pressure source 34 may be used as the brake release pressure by operating the brake by the biasing force of the spring 17. In the above-described embodiment, the planetary speed reduction mechanism 5 is used for both the braking device and the clutch device, but the present invention can be similarly applied to a brake-only device or a clutch-only device that does not have the planetary speed reduction mechanism 5.

In the correspondence between the above embodiment and the claims, the inner disc 12 is the first friction plate, the outer disc 13 is the second friction plate, the carrier shaft 54 is the rotating body, and the brake disc 14 is the same. The hydraulic pressure source 34, the pressure reducing valve 32, and the hydraulic cylinder 15 constitute the pressing member, and form the pressure contact force adjusting means. Also, the rods 41 and 42 and the counterbore 12
b, 13b, convex portions 12c, 13c, and ring members 43, 44
Respectively constitute spring fixing means.

[0034]

As described above in detail, according to the present invention, the coil springs for exerting the separating force are respectively interposed between the first friction plates and the second friction plates, and the coil springs are Since the first friction plate and the second friction plate are fixed at predetermined positions, the displacement of the spring can be prevented. As a result, the gaps between the friction plates can be made uniform, and the drag resistance acting on the friction plates can be reduced as much as possible.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of a winch having a wet multi-plate brake device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the configuration of the brake device according to the first embodiment of the present invention.

FIG. 3 is an enlarged view of a main part of FIG. 2, showing a brake released state.

FIG. 4 is an enlarged view of a main part of FIG. 2, showing a brake operating state.

FIG. 5 is a perspective view of an inner disc and an outer disc that constitute the brake device according to the first embodiment of the present invention.

FIG. 6 is a sectional view showing a configuration of a brake device according to a second embodiment of the present invention.

7 is an enlarged view of a main part of FIG.

FIG. 8 is a cross-sectional view showing the configuration of a brake device according to a third embodiment of the present invention.

9 is an enlarged view of a main part of FIG.

FIG. 10 is a cross-sectional view showing the configuration of a brake device according to a fourth embodiment of the present invention.

11 is an enlarged view of a main part of FIG.

FIG. 12 is a side view of a crane to which the present invention is applied.

[Explanation of symbols]

11 Brake Case 12 Inner Disc 13 Outer Disc 14 Brake Disc 15 Hydraulic Cylinder 18, 19 Coil Spring 32 Pressure Reducing Valve 33 Electromagnetic Changeover Valve 34 Hydraulic Source 36 Freefall Switch 54 Carrier Shaft 41, 42 Rod 12b, 13b Spot facing 12c, 13c Convex Part 43,44 ring member

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3J057 AA04 BB04 CA09 DC05 GA49                       GA80 HH10 JJ01                 3J058 AA44 AA48 AA53 AA59 AA77                       AA83 AA87 BA16 CC03 CC76                       FA39

Claims (8)

[Claims] 1. A plurality of first friction plates axially movably engaged with an outer peripheral surface of a rotating body, and axially movably engaged with an inner peripheral surface of a case accommodating the rotating body. And a plurality of second friction plates arranged alternately with the first friction plate in the axial direction, and by pushing the first friction plate and the second friction plate in the axial direction, A pressing member that exerts a pressing force on the first friction plate and the second friction plate; a pressing force adjusting unit that drives the pressing member to adjust the pressing force; and between the first friction plates and the first friction plate. A coil spring that is interposed between two friction plates and that applies a separating force to the first friction plates and the second friction plates, and the first friction plate and the second friction plate. And a spring fixing means for fixing the coil spring at a predetermined position. 2. The wet multi-plate brake device according to claim 1, wherein the spring fixing means axially penetrates the first friction plate and the second friction plate, and the inside of the coil spring. A wet multi-plate brake device having a rod member penetrating through the. 3. The wet multi-plate brake device according to claim 1, wherein the spring fixing means corresponds to an outer peripheral shape of the coil spring on the surfaces of the first friction plate and the second friction plate, respectively. A wet multi-plate brake device having a recess formed therein, wherein the coil spring is provided in the recess. 4. The wet multi-plate brake device according to claim 1, wherein the spring fixing means corresponds to an inner peripheral shape of the coil spring on the surfaces of the first friction plate and the second friction plate, respectively. A wet multi-plate brake device, characterized in that the coil spring is provided on the convex portion. 5. The wet multi-plate brake device according to claim 1, wherein the spring fixing means is respectively interposed between the first friction plates and is movable axially on the outer peripheral surface of the rotating body. A first ring member engaged with the second friction plate, and a second ring member interposed between the second friction plates and axially movably engaged with the inner peripheral surface of the case. The coil spring interposed between the first friction plates is the first
The wet multi-plate brake device, wherein the coil spring is provided so as to penetrate through the second ring member, and the coil spring interposed between the second friction plates is provided through the second ring member. 6. The first according to any one of claims 1 to 5.
The friction plate, the second friction plate, the pushing member, the pressure adjusting means, the coil spring, and the spring fixing means.
The wet multi-plate clutch device, wherein the power of the rotating body is transmitted / non-transmitted to the case via the friction plate and the second friction plate. 7. A hoisting device for a crane, comprising the wet multi-plate brake device according to claim 1. Description: 8. A hoisting device for a crane, comprising the wet multi-plate clutch device according to claim 6.