US3589384A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flow rate-responsive fuel mixture control device with servomechanism
Assignee: Robert Bosch GmbH
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Filing: 1968-12-10
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Granted: 1971-06-29
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Expires: 1988-12-10
Abstract
Abstract In the air suction tube of a fuel injection system associated with an internal combustion engine, there is displaceably held a control member which regulates a flow passage section for the air and meters the fuel in response to the change in the flow rate of air in the suction tube. The change in the static air pressure due to the change in the flow rate is utilized as an input force to control a servocircuit whose relatively large output force is used directly to displace said control member.
Inventors
- 👤 Konrad Eckert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:50
CPC Classifications
F; F02; F02M; F02M69/00; F02M69/16; F02M69/18; F02M69/22; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2499; Y10T137/3367; Y10T137/3421; Y10T137/7722; Y10T137/7758; Y10T137/7759; Y10T137/776
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
197 words
A fuel injection system associated with an internal combustion engine, comprising A. a suction tube for drawing air, B. a throttle in said suction tube for arbitrarily controlling the flow rate of air therein, C. a fuel metering device including a throttle, D. a control member at least partially disposed in said suction tube and held displaceably therein, said control member being displaced in response to changes in said flow rate; said control member, by virtue of its displacement, simultaneously varying an air flow passage section in said suction tube and controlling the throttle of said fuel metering device, E. a hydraulic servo mechanism for displacing said control member and including 1. displaceable means responsive to the changes in the static air pressure prevailing in the approximately narrowest part of said flow passage section, and 2. a servocircuit controlled by said displaceable means for moving said control member in a direction of decreasing said flow passage section when said static pressure increases and in a direction of increasing said flow passage section when said static pressure decreases; said servo mechanism tending to maintain constant said static pressure at the approximately narrowest portion of said flow passage section.
Claim 2
Dependent Claim
197 words
A fuel injection system associated with an internal combustion engine, comprising A. a suction tube for drawing air, B. a throttle in said suction tube for arbitrarily controlling the flow rate of air therein, C. a fuel metering device including a throttle, D. a control member at least partially disposed in said suction tube and held displaceably therein, said control member being displaced in response to changes in said flow rate; said control member, by virtue of its displacement, simultaneously varying an air flow passage section in said suction tube and controlling the throttle of said fuel metering device, E. a hydraulic servo mechanism for displacing said control member and including 1. displaceable means responsive to the changes in the static air pressure prevailing in the approximately narrowest part of said flow passage section, and 2. a servocircuit controlled by said displaceable means for moving said control member in a direction of decreasing said flow passage section when said static pressure increases and in a direction of increasing said flow passage section when said static pressure decreases; said servo mechanism tending to maintain constant said static pressure at the approximately narrowest portion of said flow passage section.
Claim 3
Dependent Claim
61 words
a servocircuit controlled by said displaceable means for moving said control member in a direction of decreasing said flow passage section when said static pressure increases and in a direction of increasing said flow passage section when said static pressure decreases; said servo mechanism tending to maintain constant said static pressure at the approximately narrowest portion of said flow passage section.
Claim 4
Dependent Claim
61 words
a servocircuit controlled by said displaceable means for moving said control member in a direction of decreasing said flow passage section when said static pressure increases and in a direction of increasing said flow passage section when said static pressure decreases; said servo mechanism tending to maintain constant said static pressure at the approximately narrowest portion of said flow passage section.
Claim 5
Dependent Claim
35 words
The improvement as defined in claim 1, wherein said displaceable means includes an actuator member directly affected by said static pressure and a servo element movable by said actuator member for controlling said servo circuit.
Claim 6
Dependent Claim
83 words
The improvement as defined in claim 2, wherein said suction tube includes a funnel-shaped portion, a guiding tube coaxially and fixedly held in said suction tube, said control member includes a hollow cylinder axially slidably held on said guiding tube and a piston fixedly secured to the inside of said cylinder and slidably received in said guiding tube, said piston is directly affected by the opposing forces of a hydraulic fluid in said servocircuit and of a spring disposed within said guiding tube.
Claim 7
Dependent Claim
42 words
The improvement as defined in claim 3, wherein said actuator member is a membrane, one side of which is exposed to said static air pressure, the other side of which is exposed to the total air pressure prevailing in said suction tube.
Claim 8
Dependent Claim
24 words
The improvement as defined in claim 4, wherein the force of said static pressure is aided by a spring in engagement with said membrane.
Claim 9
Dependent Claim
119 words
The improvement as defined in claim 3, wherein said servo element is formed by a piston plunger attached to and movable by said actuator member; said piston plunger is, when said static pressure increases, adapted to establish communication between the inside of said guiding tube and a means containing hydraulic fluid under pressure, causing thereby to displace said piston and said cylinder in an upstream direction to decrease said flow passage section; said piston plunger is, when said static pressure decreases, adapted to establish communication between the inside of said guiding tube and a tank means, causing thereby said piston and said cylinder to be displaced by said spring in a downstream direction to increase said flow passage section.
Claim 10
Dependent Claim
68 words
The improvement as defined in claim 6, wherein said piston plunger is adapted to interrupt communication both between the inside of said guiding tube and said means containing hydraulic fluid and between the inside of said guiding tube and said tank means to confine hydraulic fluid inside said guiding tube for arresting the motion of said piston and said cylinder when said static pressure assumes its original value.
Claim 11
Dependent Claim
61 words
The improvement as defined in claim 7, wherein said hydraulic fluid is fuel used for combustion in said engine, said tank means is constituted by a fuel tank and said means containing hydraulic fluid under pressure is a conduit communicating with said fuel tank and containing fuel pressurized by a fuel pump that simultaneously delivers fuel to said fuel metering device.
Claim 12
Dependent Claim
41 words
The improvement as defined in claim 3, wherein the outer face of said cylinder is, in its upstream portion, conically shaped and defines, together with said funnel-shaped portion of said suction tube, said flow passage section varied by said control member.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |