JP2007170543A - Brake mechanism of hydraulic motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce energy loss caused by a brake disc attached to a cylinder block and improve energy efficiency of a hydraulic motor. <P>SOLUTION: The block side brake disc 14 is attached so as to move in the axial direction at the outer periphery of the cylinder block 12 and rotate together with the cylinder block 12. A case side brake disc 15 is arranged so as to engage with the block side brake disc 14 and is attached so as to move in the axial direction at the inner periphery of a case 11. A brake piston 16 generates energizing force so as to bring an abutting face 21 of the block side brake disc 14 and an abutting face 22 of the case side brake disc 15 into pressure-contact mutually. The abutting face 21 has lower degree of roughness than that of the abutting face 22 and is formed into a smooth condition. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  According to the present invention, in a hydraulic motor that outputs rotational force by rotation of a cylinder block that is housed in a case and in which a plurality of pistons are inserted, a brake disk attached to each of the cylinder block side and the case side makes contact. The present invention relates to a brake mechanism that generates a braking force.

  Conventionally, a case in which oil is sealed, a cylinder block that is housed in the case and in which a plurality of pistons are inserted, and an output shaft that is rotatably held in the case and outputs a rotational force generated by the rotation of the cylinder block are provided. A brake mechanism that generates a braking force by a disc brake in a hydraulic motor is known (see, for example, Patent Document 1). The brake mechanism of the hydraulic motor described in Patent Document 1 is configured to generate a braking force by pressing a brake disc attached to the cylinder block so as to rotate together with the case by the brake drive mechanism. .

Japanese Patent Laid-Open No. 2004-60508

  However, in the brake mechanism of a conventional hydraulic motor such as the brake mechanism described in Patent Document 1, the surface of the brake disk attached to the cylinder block is formed to have a high roughness to ensure frictional force. Has been. For this reason, it is conceivable that the stirring resistance generated by stirring the oil in the case when the brake disk rotates with the cylinder block increases as the surface roughness increases. As a result of conducting researches focusing on this point for the first time, the present inventors have found that energy loss due to the stirring resistance of the brake disk attached to the cylinder block reaches 25% of the resistance loss of the motor depending on the condition setting. I found out.

  In view of the above circumstances, the present invention provides a brake mechanism that can reduce energy loss caused by a brake disk attached to a cylinder block and improve the energy efficiency of a hydraulic motor. With the goal.

Means and effects for solving the problems

  In order to achieve the above object, a hydraulic motor brake mechanism according to the present invention includes a case in which oil is sealed, a cylinder block that is housed in the case and in which a plurality of pistons are inserted, and rotation by rotation of the cylinder block. An output shaft that outputs force and is rotatably held with respect to the case, and is movable with respect to the cylinder block so as to be movable in the axial direction on the outer periphery of the cylinder block and to rotate with the cylinder block. An attached block-side brake disc, a case-side brake disc arranged to be engageable with the block-side brake disc and attached to the case so as to be movable in the axial direction on the inner periphery of the case, and the block side Brake disc contact surface and case-side brake disc contact surface A brake piston for generating an urging force so as to press-contact the brake mechanism, wherein the contact surface of the block-side brake disk has a lower roughness than the contact surface of the case-side brake disk It is formed so as to be in a smooth state.

  According to this configuration, the contact surface of the block-side brake disk is formed to be smoother with a lower roughness than the contact surface of the case-side brake disk. For this reason, a high frictional force can be ensured by the contact surface of the case-side brake disc. On the other hand, even if the block-side brake disc rotates with the cylinder block and stirs the oil in the case, the stirring resistance is reduced. Will be. Therefore, energy loss caused by the brake disk attached to the cylinder block can be reduced, and the energy efficiency of the hydraulic motor can be improved.

  In the brake mechanism of the hydraulic motor according to the present invention, it is desirable that the contact surface of the case-side brake disk is formed in an uneven shape.

  According to this configuration, the contact surface of the case-side brake disc is formed in a concave-convex shape, thereby ensuring a higher frictional force with a simple structure without causing a decrease in energy efficiency due to the brake disc. Can do.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a brake mechanism 1 (hereinafter also simply referred to as “brake mechanism 1”) of a hydraulic motor according to an embodiment of the present invention. The brake mechanism 1 according to the present embodiment can be applied to, for example, a hydraulic motor used as a driving device such as a crawler type traveling device such as a traveling device of a construction machine. Any motor can be widely applied. FIG. 1 is a cutaway cross-sectional view showing an extracted portion of the brake mechanism 1 in the hydraulic motor.

  As shown in FIG. 1, the brake mechanism 1 includes a case 11, a cylinder block 12, an output shaft 13, a block-side brake disc 14, a case-side brake disc 15, a brake piston 16, and the like.

  The case 11 is attached to a main body of a crawler type traveling device or the like (not shown), and oil is enclosed in the case 11. The cylinder block 12 is accommodated in the case 11. A plurality of cylinders 17 are formed in the cylinder block 12, and pistons 18 are inserted into the cylinders 17 so as to be reciprocally movable. The cylinder block 12 is rotated by the reciprocating motion of the piston 18 in contact with the swash plate 19 by the pressure oil supplied to and discharged from each cylinder 17. The output shaft 13 is rotatably held at one end side with respect to the case 11 and outputs a rotational force generated by the rotation of the cylinder block 12. The other end of the output shaft 13 is connected to a speed reduction mechanism (not shown), and a crawler type traveling device or the like can be driven to rotate through the speed reduction mechanism.

  As shown in the plan view of FIG. 3, the block-side brake disk 14 is formed in a ring shape. As shown in FIG. 1, two block side brake disks 14 (14 a, 14 b) are attached to the cylinder block 12, and rotate together with the cylinder block 12. The block-side brake disc 14 is disposed on the inner peripheral side of the block-side brake disk 14 so as to be movable in the axial direction (axial direction of the output shaft 13) on the outer periphery of the cylinder block 12 via spline coupling.

  Further, as shown in the plan view of FIG. 4, the case-side brake disk 15 is also formed in a ring shape. As shown in FIG. 1, two case side brake disks 15 (15 a, 15 b) are attached to the case 11, and are arranged to be able to engage with the block side brake disk 14. Further, the case-side brake disk 15 is disposed on the outer peripheral side thereof so as to be movable in the axial direction via spline coupling on the inner periphery of the case 11.

  As shown in FIG. 1, the brake piston 16 is formed in a ring shape and is disposed so as to be inserted into the opening on one end side of the case 11. The brake piston 16 is formed between the inner periphery of the case 11 and the outer periphery of the cylinder block 12. It is arrange | positioned so that reciprocation is possible between them. The brake piston 16 can form a hydraulic chamber 23 to which pressure oil is supplied between the brake piston 16 and a step portion formed on the inner periphery of the case 11. The brake piston 16 is biased toward the case 11 by a plurality of springs 20 arranged along the circumferential direction of the brake piston 16, An urging force is generated so that the contact surface 21 (see FIG. 3) and the contact surfaces 22 (see FIG. 4) on both sides of the case-side brake disk 15 are pressed against each other.

  The contact surface 22 of the case-side brake disc 15 is in a state in which the lining material is attached and the surface finish is performed. Thereby, the contact surface 21 of the block side brake disc 14 is formed to be smoother with a lower roughness than the contact surface 22 of the case side brake disc 15. Further, the contact surface 22 of the case side brake disk 15 is formed in an uneven shape (see FIG. 4). In addition, according to forming the contact surface 21 of the block side brake disk 14 in a smooth state, the surface roughness of the contact surface 22 of the case side brake disk 15 is appropriately increased in order to ensure a necessary frictional force. You may set so that.

  Next, the operation of the brake mechanism 1 will be described. The brake mechanism 1 is used, for example, as a parking brake that exerts a braking force when a construction machine or the like to which the brake mechanism 1 is applied is parked and the hydraulic motor is not operating. The cross-sectional view of FIG. 1 shows a state where the hydraulic motor is operating and the cylinder block 12 is rotating. On the other hand, the cross-sectional view of FIG. 2 shows a state in which the rotation of the hydraulic motor is stopped and the brake mechanism 1 operates as a parking brake to exert a braking force.

  In the state shown in FIG. 1, pressure oil discharged from a hydraulic pump (not shown) is supplied to the hydraulic chamber 23, whereby the brake piston 16 moves against the biasing force of the spring 20 and is expanded. A hydraulic chamber 23 is formed. For this reason, the urging force which press-contacts the contact surface 21 of the block side brake disk 14 and the contact surface 22 of the case side brake disk 15 does not generate | occur | produce between the block side brake disk 14 and the case side brake disk 15. No braking force is generated. And since the surface (namely, contact surface 21) of the block side brake disk 14 which rotates with the cylinder block 12 has a low roughness and is in a smooth state, the block side brake disk 14 rotates and is enclosed in the case 11. The agitation resistance generated when agitating the oil used is very small.

  On the other hand, the rotation of the cylinder block 12 is stopped in a state where the supply and discharge of the pressure oil to each cylinder 17 is stopped and the hydraulic motor is not operated. When the brake mechanism 1 as a parking brake is operated, the pressure oil in the hydraulic chamber 23 is discharged in a state where the rotation of the cylinder block 12 is stopped. For this reason, the brake piston 16 moves toward the brake disc (14, 15) side by the urging force from the spring 20, and the contact surface 21 of the block side brake disc 14 and the contact surface of the case side brake disc 15 are moved. Therefore, an urging force is generated so as to press-contact with 22. As a result, a braking force is generated between the block-side brake disc 14 and the case-side brake disc 15, and the function as a parking brake is performed.

  As described above, according to the brake mechanism 1 of the hydraulic motor according to the present embodiment, the contact surface 21 of the block-side brake disk 14 has a lower roughness and is smoother than the contact surface 22 of the case-side brake disk 15. It is formed to become. For this reason, a high frictional force can be ensured by the contact surface 22 of the case side brake disc 15, while the block side brake disc 14 rotates with the cylinder block 12 and stirs the oil in the case 11. Agitation resistance will be reduced. Therefore, energy loss caused by the brake disk attached to the cylinder block can be reduced, and the energy efficiency of the hydraulic motor can be improved.

  In addition, according to the brake mechanism 1 of the hydraulic motor, the contact surface 22 of the case-side brake disk 15 is formed in a concavo-convex shape. A higher frictional force can be ensured.

  Further, according to the brake mechanism 1 of the hydraulic motor, for example, when used in a construction machine, the hydraulic energy necessary for the operation of the construction machine can be reduced by improving the energy efficiency of the hydraulic motor. For this reason, it is possible to reduce the size of the engine for generating hydraulic energy.

  Further, according to the brake mechanism 1 of the hydraulic motor, the agitation resistance caused by the rotation of the block side brake disc 14 in the oil during the rotation of the cylinder block 12 can be made extremely small. It is possible to suppress the disk 14 from rotating while slightly swinging so as to wave. Further, by suppressing the undulating rotation in this way, it is possible to prevent the block side brake disk 14 from coming into contact with the case side brake disk 15 during the rotation and generating a frictional resistance. The energy efficiency of the hydraulic motor can be improved.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. For example, in this embodiment, the lining material is attached to the contact surface of the block side brake disc so that the roughness is higher than that of the contact surface of the case side brake disc. However, this is not necessarily the case. Alternatively, the roughness of the contact surface of the block-side brake disk may be increased by other methods. Further, the contact surface of the block-side brake disk does not necessarily have to be formed in an uneven shape. Further, the number of arrangement of the block-side brake disc and the case-side brake disc may not be as in the present embodiment, and can be changed as appropriate. It can also be used as a brake for purposes other than parking brakes.

It is sectional drawing of the brake mechanism of the hydraulic motor which concerns on one embodiment of this invention. It is sectional drawing of the brake mechanism of the hydraulic motor which concerns on one embodiment of this invention. It is a top view of the block side brake disc in the brake mechanism shown in FIG. It is a top view of the case side brake disc in the brake mechanism shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hydraulic motor brake mechanism 11 Case 12 Cylinder block 13 Output shaft 14, 14a, 14b Block side brake disk 15, 15a, 15b Case side brake disk 16 Brake piston 18 Piston 21 Contact surface of block side brake disk 22 Case side brake Disc contact surface

Claims (2)

A case filled with oil,
A cylinder block housed in the case and having a plurality of pistons inserted therein;
An output shaft that outputs rotational force due to rotation of the cylinder block and is held rotatably with respect to the case;
A block-side brake disc attached to the cylinder block so as to be movable in the axial direction on the outer periphery of the cylinder block and to rotate with the cylinder block;
A case-side brake disc that is arranged to be engageable with the block-side brake disc and is attached to the case so as to be movable in the axial direction on the inner periphery of the case;
A brake piston that generates a biasing force so as to press-contact the contact surface of the block-side brake disc and the contact surface of the case-side brake disc;
A brake mechanism of a hydraulic motor comprising:
A brake mechanism for a hydraulic motor, wherein the contact surface of the block-side brake disk is formed to have a lower roughness and a smoother state than the contact surface of the case-side brake disk.   The brake mechanism for a hydraulic motor according to claim 1, wherein the contact surface of the case-side brake disk is formed in an uneven shape.

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