JPS6429504U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a part of a first embodiment of the present invention using circuit symbols. FIG. 2 is a sectional view showing a part of a second embodiment of the present invention using circuit symbols. FIG. 3 is a sectional view showing a third embodiment of the present invention. 1... Hydraulic motor, 2... Main switching valve, 3... Pilot pump, 4... Brake cylinder, 5...
...Switching valve, 6...Pilot control valve, 7...Piston, 9...Pressure compensation spool, 11...First throttle, 12...Pressure compensation spring, 20...Brake, 21...Output shaft, 22 ...Spring, 29...Second
aperture.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A brake that brakes and releases the output shaft of a hydraulic motor, and a built-in spring that applies the brake using pressure oil from a pilot hydraulic pump that acts in opposition to the output of the spring. A main switching valve that switches the supply and discharge of pressure oil that drives the hydraulic motor, a pilot control valve that switches the main switching valve using pressure oil from a pilot pump, and In a brake device for a hydraulic motor consisting of a first throttle that controls the flow rate of pressure oil discharged to a pressure oil, and a pressure compensation spool that maintains a constant pressure difference before and after the first throttle, a pressure compensation spool provided coaxially with the pressure compensation spool is used. a piston having a pressure compensating spring sandwiched between the piston and the spool; a switching valve that supplies or cuts off pressure oil of the pilot pump to the brake cylinder, the pressure compensating spool, and the back of the piston according to switching of the pilot control valve;
A brake device for a hydraulic motor, characterized in that a second throttle is provided between the back surface of the piston and the downstream side of the first throttle. 2. A brake device for a hydraulic motor according to claim 1, characterized in that the first throttle is built into the pressure compensating spool. 3. A brake device for a hydraulic motor according to claim 1 or 2, characterized in that the second throttle is built into the piston. 4 Utility model registration claims 1 and 2, characterized in that the switching valve is a spring center 3-position switching valve in which both pilot connection ports for switching the valve are respectively connected to the pilot pressure oil of the main switching valve. Or a brake device for a hydraulic motor according to item 3. 5. Claims 1 and 2 for registration of a utility model in which the switching valve is a spring offset two-position switching valve in which the pilot connection port for switching the valve is connected to both pilot pipes of the main switching valve via a shuttle valve. Or a brake device for a hydraulic motor according to item 3. 6. A brake device for a hydraulic motor according to claim 4 or 5, wherein the first throttle, the second throttle, the pressure compensating spool, and the piston are built into the case of the hydraulic motor.