OIL PRESSURE CONTROL DEVICE

• US 20150139815A1
• Filed: 11/14/2014
• Published: 05/21/2015
• Est. Priority Date: 11/15/2013
• Status: Active Grant

• Current Assignee: Okuma Corporation
• Original Assignee: Okuma Corporation
• Inventors: Shibata, Tomohiro
• Granted Patent: US 9,932,979 B2
• Time in Patent Office: Days
• US Class Current: 417/42
• CPC Class Codes: F04B 49/065 and making use of computers
• CPC Class Codes: F04B 49/20 by changing the driving speed

Abstract

An oil pressure control device for supplying oil pressure by rotating a hydraulic pump, by means of a motor, comprises an oil pressure sensor; a speed instruction operation unit for outputting a speed instruction value, based on a difference between an oil pressure determination value from the oil pressure sensor and an oil pressure instruction value; a torque instruction value operation unit for calculating a torque instruction value, based on a difference between a speed determination value and the speed instruction value; and a current control unit for controlling a current of the motor, based on the torque instruction value, and adds the load variation compensation speed outputted from the load variation compensation unit and the speed instruction value.

Claims

1. An oil pressure control device for supplying oil pressure by rotating a hydraulic pump, using a motor, comprising:

an oil pressure sensor operatively placed between the hydraulic pump and a load;

a speed instruction operation unit configured to output a speed instruction value, based on a difference between an oil pressure determination value output from the oil pressure sensor and an oil pressure instruction value;

a load variation compensation unit configured to output a load variation compensation speed for compensating the speed instruction value outputted from the speed instruction operation unit, depending on variation of the load;

a torque instruction value operation unit configured to output a torque instruction value, based on a difference between a speed determination value obtained by differentiating a position determination value output from a motor position determination unit mounted on the motor and a sum of the speed instruction value and the load variation compensation speed; and

a current control unit adapted to control a current of the motor, based on the torque instruction value.

2. The oil pressure control device according to claim 1, wherein the load variation compensation unit is configured to output the load variation compensation speed, based on the oil pressure determination value.

3. The oil pressure control device according to claim 1, wherein the load variation compensation unit is configured to output the load variation compensation speed in response to a signal indicating a load operation pattern outputted from a superior control device.

4. The oil pressure control device according to claim 1, wherein the load variation compensation unit is configured to output as the load variation compensation speed the larger of:

(i) a load variation compensation speed calculated based on the oil pressure determination value; and

(ii) a load variation compensation speed calculated based on a signal indicating a load operation pattern outputted from a superior control device.