# US 4,377,994 A · Rpm Governor for fuel-injected interval combustion engines, especially a centrifugal governor of an injection pump for diesel motor vehicle engines > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,377,994 A - Document ID: US4377994A - Status: Granted - Kind: A - Application number: 06/389,342 - Filed: 1982-06-17 - Granted: 1983-03-29 - Earliest claimed: 1979-01-25 - Assignees: Robert Bosch GmbH - Inventors: Thomas Lang - Web page: https://patentgrep.com/patent/US4377994A ## CPC - F02D 1/08: Transmission of control impulse to pump control, e.g. with power drive or power assistance - F02D 1/10: mechanical - F02B 3/06: with compression ignition (compression ignition engines using air or gas for blowing fuel into compressed air in cylinder F02B13/02) - F02D: CONTROLLING COMBUSTION ENGINES (vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed B60K31/00; conjoint control of vehicle sub-units of different type or different function, road vehicle drive control systems for purposes other than the control of a single sub-unit B60W) - F02B: INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL (gas-turbine plants F02C; hot-gas or combustion-product positive-displacement engine plants F02G) ## Abstract An rpm governor for fuel-injected internal combustion engines is proposed, in particular a centrifugal rpm governor of an injection pump for Diesel motor vehicles, in which the idling rpm is also held constant when the engine is cold or loaded by additional consumers, in order to assure smooth running of the engine and the most favorable values for fuel consumption and exhaust emissions. The governor contains an idling correction apparatus with an electromagnet, which transmits an additional adjustment force, which is preferably independent of travel distance and variable only by the energizing current of a control circuit, onto the governor member via a transmission element. By means of varying or switching on or off of the adjustment force, the idling rpm which is fixed by the initial stress of an idling spring for the warm and unloaded engine is also held constant under changing operational conditions. ## Claims ### Claim 1 An rpm governor for a fuel-injected internal combustion engine, in particular, a centrifugal rpm governor of an injection pump for a Diesel motor vehicle engine, having a housing, a governor member which adjusts in accordance with rpm, a supply quantity adjustment member, at least one intermediate lever wherein control movements of said governor member are transmissible via said at least one intermediate lever onto said supply quantity adjustment member of said injection pump, and an idling spring wherein said governor member operates within an idling sleeve path of travel against the force of said idling spring, said rpm governor having an idling correction apparatus including an electromagnet having a coil, an armature and a pressure pin which is firmly connected to said armature and in pressure contact with said idling spring which influences the idling operation and said electromagnet is triggered in accordance with at least one engine parameter by means of a control circuit characterized in that said governor member can be acted upon additionally by an adjustment force of said electromagnet, which said adjustment force is variable by means of an energizing current of said control circuit in accordance with at least said one engine parameter and is independent of an adjustment path within which said electromagnet operates in order to maintain the idling rpm. ### Claim 2 (depends on 1) An rpm governor in accordance with claim 1, further characterized wherein said armature engages said governor member by means of a transmitting element movable in accordance with rpm by said governor member. ### Claim 3 (depends on 2) An rpm governor in accordance with claim 2 which further includes a guide lever supported on a rotary axis attached to said housing and arranged to guide one end of said governor member, further characterized wherein said guide lever acts as said transmitting element. ### Claim 4 (depends on 3) An rpm governor in accordance with claim 3, characterized wherein said guide lever is further provided with a coupler part which is engaged by a pressure pin actuated by said armature of said electromagnet. ### Claim 5 (depends on 4) An rpm governor in accordance with claim 4, characterized wherein said pressure pin further comprises a telescopable casing containing a deflection spring means. ### Claim 6 (depends on 2) An rpm governor in accordance with claim 2, further including a force transmitting member subject to the restoring force of a main control spring and arranged to contact a stop attached to the housing further characterized wherein said force transmitting element further includes a pressure pin. ### Claim 7 (depends on 6) An rpm governor in accordance with claim 6, characterized wherein said pressure pin is slidably guided in a bore of a stroke stop means therein. ### Claim 8 (depends on 7) An rpm governor in accordance with claim 7, further characterized wherein said electromagnet and said pressure pin have axes coincident with said governor member. ### Claim 9 (depends on 2) An rpm governor in accordance with claim 2, further characterized wherein said armature engages said governor via a yieldable deflection member provided with a deflection spring means. ### Claim 10 (depends on 1) An rpm governor in accordance with claim 1, characterized wherein said control circuit further contains at least one control member which functions in accordance with time. ### Claim 11 (depends on 1) An rpm governor in accordance with claim 1, characterized wherein said control circuit further includes a control element having a switch means disposed in series with said coil of said electromagnet and said control circuits further arranged to function in accordance with temperature. ### Claim 12 (depends on 11) An rpm governor in accordance with claim 11, wherein said temperature-dependent control element further includes at least one preliminary resistor, said resistor being adapted to an additional load on said engine and capable of being switched in parallel with a temperature-dependent control element. ### Claim 13 (depends on 1) An rpm governor in accordance with claim 1, further characterized wherein said control circuit is fed an engine parameter by an rpm transducer and after comparison with a desired rpm value is converted into an energizing current which determines the adjustment force of said corrective final control element. ### Claim 14 (depends on 1) An rpm governor in accordance with claim 1, characterized wherein said control circuit further includes a control element having a switch disposed in series with said coil of said electromagnet and said control circuit is further arranged to function in accordance with one engine parameter.