JPH0720201Y2 - Swing brake device for construction machinery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a swing brake device applied to a swing bearing portion of a construction machine such as a hydraulic excavator or a crane.

[Prior Art] An example of a conventional slewing bearing portion of a construction machine will be described with reference to FIGS. 11 to 13. In FIG. 11, 1 is an upper revolving structure, 2 is a lower traveling structure, and 30 is a revolving bearing part. The revolving of this device is fixed to the upper revolving structure 1 around the inner ring 30b fixed to the lower traveling structure 2. This is performed by sliding the rotating outer ring 30a. Reference numeral 19 is a hydraulic motor that is a drive source for turning, and 4 is a turning speed reducer, the pinion shaft 22 of which meshes with a gear 40 formed on the inner peripheral surface of the inner ring 30b. Therefore, the operation of the hydraulic motor 19 causes the pinion shaft 22
Rotates, whereby the upper traveling body 1 turns around the axis X, X with respect to the lower traveling body 2. In FIG. 12, 5 is a ball bearing and 6 is a seal.

Next, as shown in the thirteenth, the swing brake and lock of the above-mentioned device are cut off of the swing drive hydraulic circuit including the switching valve 21, the relief valve 20, the hydraulic pipe 23, etc., which is connected to the hydraulic pump 18 and the hydraulic motor 19. Done by. That is, when the swing brake shuts off the hydraulic circuit by setting the switching valve 21 to the neutral position (state of FIG. 13), the inertial energy of the swing of the upper swing body 1 is transmitted to the hydraulic motor 19 via the speed reducer 4. When all the inertia energy is hydraulically relieved by the relief valve 20, the rotation of the motor 19 is stopped and the turning is stopped. Then, by maintaining this stopped state, the upper swing body 1 is locked to the inner wheel 30b, that is, the lower traveling body 2.

[Problems to be Solved by the Invention] However, at the time of the above-described turning brake, since it does not stop until all the inertia energy of the upper-part turning body 1 is hydraulically relieved, there is a problem that the brake stop time becomes long and the braking effect is poor. there were.

In addition, when the upper swing body 1 is completely stopped, the hydraulic motor 19
The output shaft of is not hydraulically locked due to the circuit shutoff of the switching valve 21, but the pinion shaft 22 and the inner ring in the swing reduction gear 4
Due to backlash due to the backlash of the gear 40 of 30b, the swing of the aircraft is large in the maximum turning radius part of the upper swing body 1 with respect to the lower traveling body 2, so that the operability of the fuselage and the contact, collision of the fuselage, etc. There was also a problem in terms of safety.

The present invention has been made in view of the above circumstances, and shortens the brake stop time to improve the effectiveness of the brake.
It is an object of the present invention to provide a swing brake device in which the lock is ensured and the shake of the machine body is eliminated.

[Means for Solving the Problems] In order to achieve the above object, a swing brake device for a construction machine or the like according to the present invention includes an outer ring fixed to a lower surface of an upper swing body,
An inner ring fixed to the upper surface of the undercarriage and having a gear engraved on the inner periphery thereof, a hydraulic motor for rotationally driving a pinion shaft meshing with the gear, a hydraulic pump, and an arrangement between the hydraulic pump and the hydraulic motor. A switching valve that is provided to switch the rotation direction of the hydraulic motor and shuts off the hydraulic circuit to the hydraulic motor, and connects the switching valve and the inlet / outlet pipe of the hydraulic motor to a pair of pipes in opposite directions. In a swing brake device for a construction machine or the like having a swing drive hydraulic circuit provided with a relief valve, the outer ring has an air chamber in which one communicates with the outside and a spring is provided, and the other has the hydraulic pressure. A piston chamber having an oil chamber connected in the middle of a pipe from the pump to the switching valve, and a piston chamber built in the piston chamber, the outer end of which is biased by the spring toward the inner ring and Piston and which separably to the inner race end protrudes from the inner circumferential surface of the outer ring, a plurality of pivoting brake more made is characterized in that it is arranged at equal intervals on a concentric circle.

[Operation] When the switching valve is set to the neutral position, the discharge circuit of the pump communicates with the oil tank, and the oil pressure decreases, so that the oil pressure in the oil chamber also decreases, and as a result, the piston advances toward the inner ring side by the urging force of the spring. Then, the end surface is pressed against the inner ring.
Therefore, since this frictional force acts as a brake, the outer wheel, that is, the upper revolving superstructure is swiftly stopped.

Further, when the turning is stopped, the piston is continuously pressed against the inner ring by the urging force of the spring, so that the frictional force securely locks the inner ring and the outer ring, that is, the upper revolving structure and the lower traveling structure.

Further, since the swing brake is housed in the outer ring, there is no portion protruding to the outer periphery of the swing bearing (outer ring).

[Embodiment] An embodiment of the present invention will be described below with reference to the accompanying drawings.

1 to 6 show an embodiment of the present invention.

In FIGS. 1, 4, and 5, 3a is an outer ring fixed to the upper swing body 1, 3b is an inner ring fixed to the lower traveling body 2,
A swivel bearing portion is formed together with the ball bearing 5 interposed between the two. In addition, a gear 31 is provided on the inner circumference of the inner ring 3b.
Is the same as that of the conventional device in that the gear 31 is meshed with the pinion shaft 22 (FIG. 11) of the turning speed reducer 4.

A ring 9 is fitted from the outer peripheral side to the lower part of the outer ring 3a,
Piston chambers 32 are formed in the inner circumferential side at equal four-divided positions (FIG. 5). A curved piston 7 as shown in FIG. 2 is housed in each piston chamber 32, and the inner end portion of the pin 7 projects from the inner peripheral surface of the outer ring 3a so as to be retractable. The piston 7 has an air chamber 33 formed on the outer peripheral side thereof.
Is urged toward the inner peripheral side by the spring 8 housed in the air chamber 33, and the air chamber 33 communicates with the outside through the air filter 25. An oil chamber 34 is formed on the inner peripheral side of the piston chamber 32, and this oil chamber 34 is connected to a swing drive hydraulic circuit 35 via a high pressure joint 17 and a pipe 24 (Fig. 6). The hydraulic circuit 35 includes an oil tank 26, a switching valve 21,
It is composed of relief valves 20, 20 and a pipe 23 connecting them, and is connected to a hydraulic motor 19 and a hydraulic pump 18. The pipe 24 is a pipe between the hydraulic pump 18 and the switching valve 21.
It is connected to the hydraulic pump 18 side of 23. In the figure, 27
Is an oil seal that prevents the ingress of lubricating oil grease enclosed in the ball bearing 5, 6 is a seal, 10, 11,
12 and 13 are O-rings, respectively.

7 to 10 show another embodiment of the present invention.

The piston 7 of the above-described embodiment has a cross section in which large and small rectangles are connected as shown in the drawing and has a shape curved in the longitudinal direction, but in another embodiment, the piston has a cylindrical shape as shown by 7a in FIG. The outer ring 3c is housed in cylindrical piston chambers 32a formed in the axial direction at positions (FIG. 9) in which the circumference of the outer ring 3c is evenly divided. The cylindrical inner end portion of the piston 7a projects from the inner peripheral surface of the outer ring 3c so as to be retractable. The piston chamber 32a is sealed by a piston cover 9a fitted from the outer peripheral side of the outer ring 3c and fastened to the outer ring 3c with bolts 14 and 15. The piston 7a is biased inward by a spring 8 housed in a cylindrical air chamber 33a formed on the outside thereof, and the air chamber 33a is connected to the outside via an air filter 25. A cylindrical oil chamber 34a is formed inside the piston chamber 32a. In addition, 11a and 12a are O-rings for sealing the piston 7a, 14 is a brake shoe, and 15 is a brake shoe.
a is an O-ring for sealing the cover 9a.

Except for the outer ring 3c, the piston 7a, the cover 9a and the parts related thereto described above, the structure is the same as that of the one embodiment described above.

Next, the operation of the above device will be described. () Shows the case of other Examples.

In the normal swing of the upper swing body 1, the switching valve 21 of FIG. 6 (FIG. 10) is switched to a predetermined swing direction to connect the circuit, and the discharge pressure of the hydraulic pump 18 is guided to the hydraulic motor 19 to rotate. . The driving force of the hydraulic motor 19 is transmitted to the swing speed reducer 4, the pinion shaft 22, and the gear 31 of the inner ring 3b shown in FIG. 11, and becomes the rotational force of the upper swing body 1. At this time, at the same time, the pump discharge pressure reaches the high pressure joint 17 through the hydraulic pipe 24 branched from between the hydraulic pump 18 and the switching valve 21, and acts as a force for retracting the piston 7 (7a) to the outer ring 3a (3c) side. That is, the piston 7 (7a) retracts while compressing the spring 8 by the pump discharge pressure flowing into the oil chamber 34 (34a), comes into contact with the ring 9 (cover 9a), and stops. As a result, the piston 7 (7a) stops at a position away from the inner ring 3b, the swing brake is released, and the hydraulic motor
The upper revolving structure 1 revolves by the driving force of 19. When the switching valve 21 is returned to the neutral position from this state, the pump discharge pressure is shut off by the switching valve 21, and the relief valve 20 works to brake as in the conventional device. Then, in this case, since the discharge circuit of the pump 18 communicates with the oil tank 26 and the hydraulic pressure is reduced,
The oil pressure in the oil chamber 34 (34a) also drops, and as a result, the piston 7 (7a) advances toward the inner ring 3b by the biasing force of the spring 8 and its end face is pressed against the inner ring 3b. Therefore,
Since this frictional force acts as a brake, the outer ring 3a (3
c) That is, the revolving of the upper revolving superstructure 1 stops immediately.

Further, when the turning is stopped, the piston 7 (7a) is continuously pressed against the inner ring 3b by the urging force of the spring 8,
The frictional force reliably locks the inner ring 3b and the outer ring 3a (3c), that is, the upper revolving structure 1 and the lower traveling structure 2. Therefore, it is possible to completely prevent the shake of the machine body due to the backlash due to the conventional backlash.

It should be noted that in the above-described embodiment, the piston 7 is provided at a plurality of locations on the outer ring 3a (equal four-divided positions in the embodiment), and in another embodiment, the piston 7a is provided at a plurality of locations on the outer ring 3c (equal eight-division positions in the embodiment). ), The pressing force on the inner ring 3b of the piston 7 (7a) is dispersed and balanced, and it is possible to avoid applying an excessive load in part and in one direction, thus improving the durability of the bearing part. To do.

In the structure of the one embodiment, since the portion of the piston 7 projecting from the inner peripheral surface of the outer ring 3a makes a circular arc-shaped surface contact with the outer side of the inner ring 3b, the braking force is strong and suitable for a relatively large model, The structure of the other embodiment is weaker in braking force than the former due to the point contact, so that it is suitable for a small model and the manufacturing cost is low.

[Effects of the Invention] As described above, according to the present invention, the turning brake stop time is shortened, the braking effectiveness is improved, the work efficiency is increased, and the hydraulic leaf by the relief valve is reduced, so that the oil temperature of the oil temperature is reduced. The rise can be reduced. Further, since the vehicle is reliably locked when the turning is stopped, the swinging of the machine body is eliminated, and the safety around the machine body is improved, and the linear workability is improved particularly in an excavating machine such as a hydraulic excavator.

Further, the present invention has the following effects because the swing brake is housed in the outer ring.

Since there is no protruding portion on the outer circumference of the slewing bearing (outer ring), the slewing brake device is not damaged by a falling object or the like from the outside.

In this type of crawler type construction machine, a crawler having a wide width is often mounted according to the needs of the customer. (Protrusion does not occur)
Since there is no, there is no interference with the crawler when installing the wide crawler. Moreover, since the external dimensions can be set to be the same as or the same as those of the standard specification bearings, the setting as an option instead of the standard specifications can be performed without affecting the body side.

Since the braking portion between the inner and outer races is sealed by the dust seal, dust or earth and sand do not enter the braking portion, and the life of both sliding parts can be increased.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention, and FIG.
FIG. 3 is a perspective view of a piston of an embodiment, FIG. 3 is a sectional view of the same, FIG. 4 is a longitudinal sectional view of an essential portion showing an embodiment of the present invention, and FIG. A plan view, FIG. 6 is a hydraulic circuit diagram for driving the same, FIG. 7 is a perspective view showing another embodiment of the present invention, FIG. 8 is a longitudinal sectional view of the same, and FIG. 9 is a main FIG. 10 is a plan view of the same, FIG. 10 is a hydraulic circuit diagram for driving the same, FIG. 11 is a partial sectional view of a conventional example, FIG. 12 is an enlarged sectional view of a main part of the conventional example, and FIG.
The figure is a conventional hydraulic circuit diagram for driving. 1 ... Upper revolving structure, 2 ... Lower revolving structure, 3a, 3c ... Outer ring, 3b ... Inner ring, 7,7a ... Piston, 8 ... Spring, 18 ... Hydraulic pump, 19 ... Hydraulic motor, 20 …… Relief valve, 21 …… Switching valve, 22 …… Pinion shaft, 23,2
4 …… Piping, 31 …… Gear, 32,32a …… Piston chamber, 33,33
a: Air chamber, 34, 34a: Oil chamber, 35: Hydraulic circuit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsue Nagao 2-5-1, Marunouchi, Chiyoda-ku, Tokyo Sanryo Heavy Industries Co., Ltd. (56) Reference JP-A-58-24627 (JP, A) JP 62-72081 (JP, A) Actual opening 60-129503 (JP, U) Actual opening 49-81601 (JP, U) Actual opening Sho 59-21132 (JP, U) Actual public 55-31096 (JP , Y2)

Claims (1)

[Scope of utility model registration request] 1. An outer ring fixed to a lower surface of an upper revolving structure, an inner ring fixed to an upper surface of a lower traveling structure and having a gear engraved on an inner periphery thereof, and a pinion shaft meshing with the gear, which are rotationally driven. A hydraulic motor, a hydraulic pump, a switching valve that is disposed between the hydraulic pump and the hydraulic motor, switches a rotational direction of the hydraulic motor, and shuts off a hydraulic circuit to the hydraulic motor, the switching valve, and the hydraulic motor. In a swing brake device such as a construction machine having a hydraulic circuit for swing drive in which a pair of pipes are provided with a pair of relief valves in opposite directions in communication with the inlet / outlet pipe, An air chamber communicating with the outside and provided with a spring, a piston chamber having an oil chamber connected to the other halfway of a pipe from the hydraulic pump to the switching valve, and a piston chamber built in the piston chamber. Plural turning brakes, each of which has an outer end urged toward the inner ring by the spring and an inner end protruding from the inner peripheral surface of the outer ring to be brought into contact with and separated from the inner ring, are arranged at equal intervals on a concentric circle. A swing brake device for construction machines, etc.