Motor-drive unit having heat radiator

• US 9,155,231 B2
• Filed: 01/14/2014
• Issued: 10/06/2015
• Est. Priority Date: 01/15/2013
• Status: Active Grant

• Current Assignee: Fanuc Corporation
• Original Assignee: Fanuc Corporation
• Inventors: Masuda, Naoki, Inaba, Kiichi
• Primary Examiner(s): Datskovskiy, Michail V
• Application Number:
  US14/154,311
• Publication Number:
  US 20140198455A1
• Time in Patent Office: 630 Days
• Field of Search: 36167946-67954, 361704-712, 361715-723, 361/732, 361/756, 361/760, 165/80.2, 165/80.3, 165/80.4, 165/104.33, 165/185, 257722-726, 174/15.1, 174/16.3, 174/252, 363/89, 363 95- 98, 363/131, 363/132, 363/123, 363/141, 363/144, 363/321, 310/67.R, 310/68.R, 310/89, 318/781, 318/784, 318/795
• US Class Current: 1/1
• CPC Class Codes: G06F 1/20 Cooling means
• CPC Class Codes: H02M 7/00 Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
• CPC Class Codes: H05K 7/20845 for automotive electronic casings H05K7/2089 takes precedence
• CPC Class Codes: H05K 7/2089 for power electronics, e.g. for inverters for controlling motor
• CPC Class Codes: H05K 7/209 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20909 takes precedence

Abstract

A compact motor-drive unit wherein each component can be stably fixed to the unit. A motor-drive unit has a plurality of substrates each having a circuit for driving a motor; semiconductor devices mounted on the respective substrates; at least one smoothing capacitor mounted on at least one of the substrates; and a heat radiator having a heat-transferring surface adjacent to the semiconductors. The smoothing capacitor is positioned within a swept area formed by moving the first substrate arranged generally parallel to a base surface, in a counter-front direction, so that the smoothing capacitor is separated from the first substrate.

Claims

1. A motor-drive unit comprising:

a first substrate and a second substrate wherein a circuit for driving a motor is divided and divided sections of the circuit are formed on the first and second substrates;

a connecting part which connects the first and second substrates so that the first and second substrates intersect with each other;

a semiconductor device mounted on each of the first and second substrates;

a heat radiator having a first heat-transferring surface adjacent to the semiconductor device mounted on the first substrate and a second heat-transferring surface having a surface direction different from a surface direction of the first heat-transferring surface; and

a capacitor positioned within a swept area formed by moving the first substrate in a direction perpendicular to the first heat-transferring surface, the capacitor being separated from the first substrate, wherein the semiconductor devices are positioned adjacent to at least the first and second heat transferring surfaces, respectively.

4. The motor-drive unit as set forth in claim 1, wherein the capacitor is mounted on an extended portion formed by extending the second substrate in a direction perpendicular to the first substrate.

5. The motor-drive unit as set forth in claim 1, wherein the heat radiator has a plurality of heat-releasing fins extending parallel to each other at an inclined angle relative to the first heat-transferring surface and at an inclined angle relative to the second heat-transferring surface.

6. The motor-drive unit as set forth in claim 1, wherein the heat radiator has a plurality of heat-releasing fins including fins extending perpendicular to the first heat-transferring surface and including fins extending perpendicular to the second heat-transferring surface.

2. A motor-drive unit comprising:

a first substrate and a second substrate wherein a circuit for driving a motor is divided and divided sections of the circuit are formed on the first and second substrates;

a connecting part which connects the first and second substrates so that the first and second substrates intersect with each other;

a semiconductor device mounted on each of the first and second substrates;

a heat radiator having a first heat-transferring surface adjacent to the semiconductor device mounted on the first substrate and a second heat-transferring surface having a surface direction different from a surface direction of the first heat-transferring surface; and

a capacitor, wherein the capacitor is a screw-fastening-type capacitor which is fastened to a first conductive arm member extending from the first substrate by means of a screw.

3. A motor-drive unit comprising:

a first substrate and a second substrate wherein a circuit for driving a motor is divided and divided sections of the circuit are formed on the first and second substrates;

a connecting part which connects the first and second substrates so that the first and second substrates intersect with each other;

a semiconductor device mounted on each of the first and second substrates;

a heat radiator having a first heat-transferring surface adjacent to the semiconductor device mounted on the first substrate and a second heat-transferring surface having a surface direction different from a surface direction of the first heat-transferring surface; and

a capacitor, wherein the capacitor is mounted on a capacitor substrate attached to a second conductive arm member extending from the first substrate.

7. A motor-drive unit comprising:

a first substrate and a second substrate wherein a circuit for driving a motor is divided and divided sections of the circuit are formed on the first and second substrates;

a connecting part which connects the first and second substrates so that the first and second substrates intersect with each other;

a semiconductor device mounted on each of the first and second substrates;

a heat radiator having a first heat-transferring surface adjacent to the semiconductor device mounted on the first substrate; and

a capacitor positioned within a swept area formed by moving the first substrate in a direction perpendicular to the first heat-transferring surface, the capacitor being separated from the first substrate,

wherein a part of the heat radiator has a projecting portion extending in a direction perpendicular to the first heat-transferring surface, and the semiconductor device is attached to the projecting portion.