# US 4,396,874 A · Magnetic apparatus for producing movement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,396,874 A - Document ID: US4396874A - Status: Granted - Kind: A - Application number: 06/344,270 - Filed: 1982-01-28 - Granted: 1983-08-02 - Earliest claimed: 1982-01-28 - Inventors: J. William Putt - Web page: https://patentgrep.com/patent/US4396874A ## CPC - H02K 33/00: Motors with reciprocating, oscillating or vibrating magnet, armature or coil system (arrangements for handling mechanical energy structurally associated with motors H02K7/00, e.g. H02K7/06) - H01F 7/1805: {Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current (for holding relay armature in attracted position with reduced energising current H01H47/04; quick energising of electro-dynamic machines H02P9/08; for quickly de-energising of dynamo-electric generators H02P9/123)} - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES ## Abstract Apparatus for providing movement includes an electromagnet. The time required to attain a given value of current flow in a magnet coil is shortened by initially providing a higher voltage to attain quickly the desired current flow, and then providing a lower voltage. ## Claims ### Claim 1 Apparatus for producing movement, comprising, a pair of paramagnetic members which are relatively movable from mutually distant positions to mutually proximate positions, said members being separated by a gap which opens and closes as the members move relatively away from and toward each other, electrical windings including at least a first coil and a second coil on one of said paramagnetic members, said windings when energized being operable to provide a magnetic field which pulls the paramagnetic members together and closes the gap between them, energizing means for applying electrical potentials to said windings, causing an electrical current to flow therethrough creating a magnetomotive force in the respective paramagnetic member, said energizing means including the following: (a) means for applying a first electrical potential to said first coil to produce the flow of electric current therethrough; and, (b) means for applying a second electrical potential to said second coil, said second electrical potential being less than said first electrical potential; said means (a) being operable to shorten the time required for current in the second coil to reach a given value. ### Claim 2 (depends on 1) The apparatus of claim 1 wherein the energizing means includes at least first and second electrical sources, and means (a) is operable to connect the first and second electrical sources in series to the first coil. ### Claim 3 (depends on 2) The apparatus of claim 2 wherein the means (b) of the control means connects one of said first and second electrical sources to the second coil. ### Claim 4 (depends on 1) The apparatus of claim 1 wherein the energizing means includes at least first and second electrical sources, and the means (a) is operable to connect the first and second electrical sources in series to the first coil; said means (b) being operable to connect the second coil in parallel to at least one of said electrical sources. ### Claim 5 (depends on 1) The apparatus of claim 1 wherein the energizing means includes at least first and second electrical sources, and the means (a) of the control means is operable to connect the first and second electrical sources in series to the first coil; and means (b) being operable to connect said first and second electrical sources in parallel to the second coil. ### Claim 6 (depends on 1, 2, 3, 4, 5) The apparatus of any one of claims 1-5 wherein the first means is operable for a time interval which is less than the time required to establish in the first coil a current of I.sub.max =E.sub.1 /R.sub.1 wherein E.sub.1 is the first electrical potential and R.sub.1 is the electrical resistance of the coil. ### Claim 7 Apparatus for producing movement, comprising, a pair of paramagnetic members which are relatively movable from mutually distant positions to mutually proximate positions, said members being separated by a gap which opens and closes as the members move relatively away from and toward each other, an electrical coil on one of said paramagnetic members, said coil when energized being operable to provide a magnetic field which pulls the paramagnetic members together and closes the gap between them, energizing means for applying electrical potentials to said coil, causing an electrical current to flow therethrough creating a magnetomotive force in the respective paramagnetic member, said energizing means including the following: (a) first means for applying a first electrical potential to said coil to establish the flow of electrical current therethrough, said first means being operable for a time interval which is less than the time required to establish a current of I.sub.max =E.sub.1 /R.sub.1 wherein E.sub.1 is the first electrical potential and R.sub.1 is the electrical resistance of the coil; (b) second means, operable after said flow of current is established, for applying a second electrical potential to said coil, said second electrical potential being less than said first electrical potential and being effective to maintain said flow of electrical current in the coil.