US 6,474,752 B2 · Rotary pump and braking device using same

Abstract

In a rotary pump, an outer rotor and an inner rotor are assembled in a casing such that, when a clearance between an inner teeth portion of the outer rotor and an outer teeth portion of the inner rotor is substantially nullified at a first closed gap portion having a maximum volume formed between the inner teeth portion and the outer teeth portion, a clearance between the outer rotor and the casing on a side of the first closed gap portion and a clearance between the outer rotor and the casing on a side of a second closed gap portion having a minimum volume, become substantially an equivalent interval. As a result, the outer rotor and the casing can be brought into contact with each other on the side of the second closed gap portion rather than the central axis of the inner rotor. Even in a high pressure discharge operation, the outer rotor is not locked by being squeezed between the inner rotor and the casing.

Drawings

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Drawings

Claims16

Dependent claims

A rotary pump comprising:

a drive shaft;
a rotating unit constituted by an outer rotor having an inner teeth portion on its inner periphery and an inner rotor having an outer teeth portion on its outer periphery, said inner rotor being rotated by said drive shaft, wherein a plurality of gap portions are formed between said inner teeth portion and said outer teeth portion by mesh thereof and each of said gap portions changes from a large volume to a small volume and vice versa when said rotating unit rotates;
and
a casing for containing said rotating unit, said casing having an opening for allowing said drive shaft to be inserted thereinto, an intake port extending along a side surface of said rotating unit perpendicular to an axis of said drive shaft over a part of said gap portions for introducing brake fluid in said part of the gap portions, and a discharge port extending along said side surface of said rotating unit perpendicular to said axis of the drive shaft over another part of said gap portions for discharging brake fluid from said another part of the gap portions, wherein a differential pressure between a pressure at said intake port and a pressure at said discharge port is maintained by a first closed gap portion of which a volume becomes a maximum and a second closed gap portion of which a volume becomes a minimum among said gap portions whereby the gap portions coming just after the second closed gap portion to the first closed gap portion perform a suction stroke and the gap portions coming just after the first closed gap portion to the second gap portion perform a discharge stroke;
a low pressure side communicating path formed in said casing so as to extend from said intake port to an outer periphery of said outer rotor on a side of said intake port;
a high pressure side communicating path formed in said casing so as to extend from said discharge port to the outer periphery of said outer rotor on a side of said discharge port;
a first seal device for restraining flow of a fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said the outer rotor on a side where said first closed gap portion is formed;
and
a second seal device for restraining flow of the fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said outer rotor on a side where said second closed gap portion is formed.

6 more elements

A rotary pump comprising:

a drive shaft;
a rotating unit constituted by an outer rotor having an inner teeth portion on its inner periphery and an inner rotor having an outer teeth portion on its outer periphery, said inner rotor being rotated by said drive shaft, wherein a plurality of gap portions are formed between said inner teeth portion and said outer teeth portion by mesh thereof and each of said gap portions changes from a large volume to a small volume and vice versa when said rotating unit rotates;
and
a casing for containing said rotating unit, said casing having an opening for allowing said drive shaft to be inserted thereinto, an intake port for introducing brake fluid in said gap portions, and a discharge port for discharging brake fluid from said gap portions, wherein a differential pressure between a pressure at said intake port and a pressure at said discharge port is maintained by a first closed gap portion of which a volume becomes a maximum and a second closed gap portion of which a volume becomes a minimum among said gap portions;
a low pressure side communicating path formed in said casing for communicating an outer periphery of said outer rotor on a side of said intake port with said intake port;
a high pressure side communicating path formed in said casing for communicating the outer periphery of said outer rotor on a side of said discharge port with said discharge port;
a first seal device disposed on the outer periphery of said the outer rotor on a side where said first closed gap portion is formed between said high pressure side communicating path and said low pressure side communicating path, for restraining flow of a fluid therebetween,
wherein said first seal device is formed at a position such that said outer rotor is moved in a direction that said inner teeth portion pushes said outer teeth portion at said first closed gap portion by a high pressure fluid introduced into the outer periphery of said outer rotor from said high pressure side communicating path.

5 more elements

A rotary pump comprising:

a drive shaft;
a rotating unit constituted by an outer rotor having an inner teeth portion on its inner periphery and an inner rotor having an outer teeth portion on its outer periphery, said inner rotor being rotated by said drive shaft, wherein a plurality of gap portions are formed between said inner teeth portion and said outer teeth portion by mesh thereof and each of said gap portions changes from a large volume to a small volume and vice versa when said rotating unit rotates;
and
a casing for containing said rotating unit, said casing having an opening for allowing said drive shaft to be inserted thereinto, an intake port for introducing brake fluid in said gap portions, and a discharge port for discharging brake fluid from said gap portions, wherein a differential pressure between a pressure at said intake port and a pressure at said discharge port is maintained by a first closed gap portion of which a volume becomes a maximum and a second closed gap portion of which a volume becomes a minimum among said gap portions;
a low pressure side communicating path formed in said casing for communicating an outer periphery of said outer rotor on a side of said intake port with said intake port;
a high pressure side communicating path formed in said casing for communicating the outer periphery of said outer rotor on a side of said discharge port with said discharge port;
a first seal device for restraining flow of a fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said the outer rotor on a side where said first closed gap portion is formed;
and
a second seal device for restraining flow of the fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said outer rotor on a side where said second closed gap portion is formed;
wherein:
said communicating paths between each of the intake port and the discharge port and the outer periphery of said outer rotor are recessed portions formed on a face opposed to the outer peripheral face of said outer rotor in wall faces of said casing constituting a chamber for containing said rotating unit.

8 more elements

A rotary pump comprising:

a drive shaft;
a rotating unit constituted by an outer rotor having an inner teeth portion on its inner periphery and an inner rotor having an outer teeth portion on its outer periphery, said inner rotor being rotated by said drive shaft, wherein a plurality of gap portions are formed between said inner teeth portion and said outer teeth portion by mesh thereof and each of said gap portions changes from a large volume to a small volume and vice versa when said rotating unit rotates;
and
a casing for containing said rotating unit, said casing having an opening for allowing said drive shaft to be inserted thereinto, an intake port for introducing brake fluid in said gap portions, and a discharge port for discharging brake fluid from said gap portions, wherein a differential pressure between a pressure at said intake port and a pressure at said discharge port is maintained by a first closed gap portion of which a volume becomes a maximum and a second closed gap portion of which a volume becomes a minimum among said gap portions;
a low pressure side communicating path formed in said casing for communicating an outer periphery of said outer rotor on a side of said intake port with said intake port;
a high pressure side communicating path formed in said casing for communicating the outer periphery of said outer rotor on a side of said discharge port with said discharge port;
a first seal device for restraining flow of a fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said the outer rotor on a side where said first closed gap portion is formed;
and
a second seal device for restraining flow of the fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said outer rotor on a side where said second closed gap portion is formed;
wherein said casing comprises:
a central plate having a hole for containing said rotating unit;
and
first and second side plates interposing said center plate;
wherein said communicating paths are formed in said casing by chamfering corner portions of an inner wall forming a hole in said central plate.

11 more elements

A rotary pump comprising:

a drive shaft;
a rotating unit constituted by an outer rotor having an inner teeth portion on its inner periphery and an inner rotor having an outer teeth portion on its outer periphery, said inner rotor being rotated by said drive shaft, wherein a plurality of gap portions are formed between said inner teeth portion and said outer teeth portion by mesh thereof and each of said gap portions changes from a large volume to a small volume and vice versa when said rotating unit rotates;
and
a casing for containing said rotating unit, said casing having an opening for allowing said drive shaft to be inserted thereinto, an intake port for introducing brake fluid in said gap portions, and a discharge port for discharging brake fluid from said gap portions, wherein a differential pressure between a pressure at said intake port and a pressure at said discharge port is maintained by a first closed gap portion of which a volume becomes a maximum and a second closed gap portion of which a volume becomes a minimum among said gap portions;
a low pressure side communicating path formed in said casing for communicating an outer periphery of said outer rotor on a side of said intake port with said intake port;
a high pressure side communicating path formed in said casing for communicating the outer periphery of said outer rotor on a side of said discharge port with said discharge port;
a first seal device for restraining flow of a fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said the outer rotor on a side where said first closed gap portion is formed;
a second seal device for restraining flow of the fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said outer rotor on a side where said second closed gap portion is formed;
wherein said casing comprises:
a central plate having a hole for containing said rotating unit;
and
first and second side plates interposing said center plate;
wherein said communicating paths are formed in said casing by forming a groove portion in a peripheral direction of said hole on an inner wall forming said hole in said central plate.

10 more elements

A brake apparatus comprising:

a brake fluid pressure generating device which generates brake fluid pressure in accordance with a braking operation carried out by a driver;
a braking force producing device which produces braking force on a wheel when receiving brake fluid pressure;
a main conduit connecting said brake fluid pressure generating device to the braking force producing device for transmitting said brake fluid pressure generated by said brake fluid pressure generating device to said braking force producing device;
an auxiliary conduit connecting said brake fluid pressure generating device to a midway point of said main conduit;
a rotary pump disposed in said auxiliary conduit for sucking brake fluid from a side of said brake fluid pressure generating device and discharging pressurized brake fluid into said main conduit;
and
a restriction device disposed in said main conduit between said brake fluid pressure generating device and said midway point of said main conduit, for restricting flow of brake fluid heading for said brake fluid pressure generating device;
wherein said rotary pump comprises:
a drive shaft;
a rotating unit constituted by an outer rotor having an inner teeth portion on its inner periphery and an inner rotor having an outer teeth portion on its outer periphery, said inner rotor being rotated by said drive shaft, wherein a plurality of gap portions are formed between said inner teeth portion and said outer teeth portion by mesh thereof and each of said gap portions changes from a large volume to a small volume and vice versa when said rotating unit rotates;
and
a casing for containing said rotating unit, said casing having an opening for allowing said drive shaft to be inserted thereinto, an intake port extending along a side surface of said rotating unit perpendicular to an axis of said drive shaft over a part of said gap portions for introducing brake fluid in said part of the gap portions, and a discharge port extending along said side surface of said rotating unit perpendicular to said axis of the drive shaft over another part of said gap portions for discharging brake fluid from said another part of the gap portions, wherein a differential pressure between a pressure at said intake port and a pressure at said discharge port is maintained by a first closed gap portion of which a volume becomes a maximum and a second closed gap portion of which a volume becomes a minimum among said gap portions whereby the gap portions coming just after the second closed gap portion to the first closed gap portion perform a suction stroke and the gap portions coming just after the first closed gap portion to the second gap portion perform a discharge stroke;
a low pressure side communicating path formed in said casing so as to extend from said intake port to an outer periphery of said outer rotor on a side of said intake port;
a high pressure side communicating path formed in said casing so as to extend from said discharge port to the outer periphery of said outer rotor on a side of said discharge port;
a first seal device for restraining flow of a fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said the outer rotor on a side where said first closed gap portion is formed;
and
a second seal device for restraining flow of the fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said outer rotor on a side where said second closed gap portion is formed.

14 more elements

A rotary pump comprising:

a drive shaft;
a rotating unit constituted by an outer rotor having an inner teeth portion on its inner periphery and an inner rotor having an outer teeth portion on its outer periphery, said inner rotor being rotated by said drive shaft, wherein a plurality of gap portions are formed between said inner teeth portion and said outer teeth portion by mesh thereof and each of said gap portions changes from a large volume to a small volume and vice versa when said rotating unit rotates;
and
a casing for containing said rotating unit, said casing having an opening for allowing said drive shaft to be inserted thereinto, an intake port for introducing brake fluid in said gap portions, and a discharge port for discharging brake fluid from said gap portions, wherein a differential pressure between a pressure at said intake port and a pressure at said discharge port is maintained by a first closed gap portion of which a volume becomes a maximum and a second closed gap portion of which a volume becomes a minimum among said gap portions;
a low pressure side communicating path formed in said casing for communicating an outer periphery of said outer rotor on a side of said intake port with said intake port;
a high pressure side communicating path formed in said casing for communicating the outer periphery of said outer rotor on a side of said discharge port with said discharge port;
a first seal device for restraining flow of a fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said the outer rotor on a side where said first closed gap portion is formed;
and
a second seal device for restraining flow of the fluid between said high pressure side communicating path and said low pressure side communicating path on the outer periphery of said outer rotor on a side where said second closed gap portion is formed;
wherein:
each of said first and second seal devices includes a first seal member arranged on a side of said casing and second seal member arranged on a side of said outer rotor, and said first seal member is formed by a material having a hardness softer than that of said second seal member.

8 more elements

Dependencies are inferred from the claim text.

Description17,605 words

Summary4,300 words

#1. Field of the Invention

#The present invention relates to a rotary pump for sucking and discharging fluid and a braking apparatus using the rotary pump. In particular, the present invention is preferably applied to an internal gear pump such as a trochoid pump or the like.

#2. Description of Related Art

Brief description of the drawings15 figures

#Other features and advantages of the present invention will be appreciated, as well as methods of operation and the function of the related parts, from a study of the following detailed description, the appended claims, and the drawings, all of which form a part of this application. In the drawings:

#FIG. 1 is a schematic view of a brake apparatus to which a rotary pump 10 is applied;

#FIG. 2A is a schematic view of the rotary pump 10 and FIG. 2B is a sectional view taken from a line IIB—IIB of FIG. 2A;

Detailed description12,967 words

#FIG. 1 shows an outline structure of a brake apparatus to which a trochoid pump is applied as a rotary pump. The basic constitution of the brake apparatus will be described with reference to FIG. 1. In this embodiment, a brake apparatus is applied to a vehicle provided with a hydraulic circuit of a diagonal conduit system having a first conduit connecting wheel cylinders of a front right wheel and a rear left wheel and a second conduit connecting wheel cylinders of a front left wheel and a rear right wheel. The vehicle is a four wheel vehicle of front wheel drive.

#As shown in FIG. 1, a brake pedal 1 is connected to a booster 2. Brake depression force (brake pedal stroke) is boosted by the booster 2.

#Further, the booster 2 is provided with a rod for transmitting boosted depression force to a master cylinder 3. In detail, the master cylinder 3 generates master cylinder pressure when the rod pushes a master piston arranged in the master cylinder 3. The brake pedal 1, the booster 2 and the master cylinder 3 correspond to a brake fluid pressure generating device.

Facts

Application

09/897,024Filed 3 Jul 2001 · division

Priority

JP 9-28066014 Oct 1997

Published

US 2002/0030402 A114 Mar 2002

Granted

5 Nov 2002

Term ended

13 Oct 2018

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification9 codes

B60T 8/4275
Having expanding chambers for controlling pressure , i.e. closed systems: pump-back systems
B60T 8/4031
Comprising an additional fluid circuit including fluid pressurising means for modifying the pressure of the braking fluid, e.g. including wheel…:…
B60T 8/4872
Closed systems: pump-back systems
F04C 2/102
Of internal-axis type with the outer member having more teeth or tooth-equivalents, e.g. rollers, than the inner member: the two members rotating…

Rotary pump and braking device using same

Life of this patent

Rotary pump and braking device using same

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims16

Description17,605 words

Drawings

Classification9 codes

Life of this patent

Description17,605 words