Parking brake device in caliper brake device for railway vehicle

Patent metadata

Field	Value
Publication number	US-10240650-B2
Application number	US-201414898494-A
Country	US
Kind code	B2
Filing date	Jun 19, 2014
Priority date	Jun 19, 2013
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

A parking brake reduced in size and simplified is installed on a rod-protruding side of a cylinder of a caliper braking device. A second piston is provided within the second cylinder that is coaxially coupled with the cylinder and movable coaxially relative to the rod. A one-way clutch is provided to switch ON/OFF due to a releasing/pressing by the second piston with respect to a switch disposed facing a cylinder side surface of the second piston. A parking operation auxiliary spring is provided on the side of the cylinder within a second cylinder, and a manual release piston is provided in a space of the second cylinder. A parking release lever pushes a manual release rod at the tip end of the manual release piston, pushing the second piston in the direction of retraction of the rod, at the same time as the manual release rod pushes into the rod.

First claim

The invention claimed is:

1. A parking brake device in a caliper brake device for a railway vehicle disposed on a rod protruding side of a rod of a piston provided to move freely within a brake cylinder, for decelerating or stopping a railway vehicle while traveling,
the parking brake device comprising a structure for holding the rod protruded from the bake cylinder and for preventing the rod from retracting, the structure being achieved by switching a one-way clutch from OFF to ON by turning a switch, which is installed on an inner peripheral side portion of a side wall of the brake cylinder, from OFF to ON by a spring force of a parking operation auxiliary spring disposed in a second cylinder coupled in series and coaxially with the brake cylinder, the OFF position of the one-way clutch not constraining a protruding/retracting movement of the rod and the ON position of the one-way clutch allowing protruding movement of the rod but preventing retracting movement.

2. The parking brake device according to claim 1 , wherein the structure for holding the rod protruded from the brake cylinder and for preventing the rod from retracting comprises:
the second cylinder;
a second piston that protrudes outwardly from a side wall of the second cylinder having a front end surface on the rod protruding side, the second piston provided within the second cylinder coaxially with the rod and movable relative to the rod;
the switch disposed in a position facing a side surface of the second piston which faces a side wall of the brake cylinder,
the switch being turned ON when it is released from a pressure from the second piston, and being turned OFF when it is pressed by the second piston;
the one-way clutch preventing the rod from retracting into the brake cylinder when the switch is turned ON;
the parking operation auxiliary spring disposed in a space on the brake cylinder side within the second cylinder which is partitioned by the second piston, and that pushes the second piston in a rod-protrusion direction, so as to release the pressure of the second piston on the switch during normal operation; and a release mechanism that presses the switch so that the second piston is pushed from outside of the second cylinder toward the rod-retraction direction.

3. The parking brake device according to claim 2 , wherein the release mechanism that presses the switch so that the second piston is pushed from outside of the second cylinder toward the rod-retraction direction comprises:
a manual release piston disposed in a space within the second cylinder on a side opposite from the brake cylinder and having a tip end protruding to the outside of the second cylinder, and which is positionable in a specified position;
a manual release rod affixed at the tip end of the manual release piston that protrudes to the outside of the second cylinder and pushes the manual release piston in the rod-retraction direction;
a parking release lever that pushes the second piston in the rod-retraction direction, against a spring force of the parking operation auxiliary spring, at the same time as the manual release rod pushes in the rod-retraction direction.

4. The parking brake device according to claim 3 , wherein the manual release piston is positioned by having a plurality of positioning indentations formed in an axial direction on an outer periphery of a shank portion of the manual release piston, and having a positioning elastic projection that engages with one of the indentations in an axial direction on the side wall of the second cylinder through which passes the shank portion on which the indentations are formed.

5. The parking brake device according to claim 1 , wherein the one-way clutch is provided on the inner peripheral side portion of the side wall of the brake cylinder.

Assignees

• Nippon Steel & Sumitomo Metal Corp

Inventors

• Kimura Ryouichi
• Fujita Kazuaki

Classifications

• F16D2125/582

  Flexible element, e.g. spring, other than the main force generating element · CPC title

• F16D2121/04

  acting on a piston-type actuator, e.g. for liquid pressure · CPC title

• B60T17/228

  for railway vehicles · CPC title

• F16D2121/16

  for releasing a normally applied brake · CPC title

• B61H5/00

  Applications or arrangements of brakes with substantially radial braking surfaces pressed together in axial direction, e.g. disc brakes · CPC title