# US 7,070,005 B2 · Soil aerator assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,070,005 B2 - Document ID: US7070005B2 - Status: Granted - Kind: B2 - Application number: 10/776,007 - Filed: 2004-02-10 - Published: 2005-08-11 - Granted: 2006-07-04 - Earliest claimed: 2004-02-10 - Assignees: PlanetAir Turf Products, LLC - Inventors: David R. Maas; Scott W. Bjorge - Web page: https://patentgrep.com/patent/US7070005B2 ## CPC - A01B 45/026: {Scarifiers comprising a knife reel actively driven around a substantially horizontal shaft} - A01B: SOIL WORKING IN AGRICULTURE OR FORESTRY; PARTS, DETAILS, OR ACCESSORIES OF AGRICULTURAL MACHINES OR IMPLEMENTS, IN GENERAL (making or covering furrows or holes for sowing, planting or manuring A01C5/00; mowers convertible to soil working apparatus or capable of soil working A01D42/04; mowers combined with soil working implements A01D43/12; soil working for engineering purposes E01, E02, E21) ## Abstract In certain embodiments a soil aerator may include a hinged frame assembly that cooperates with one or more weight transferring systems adapted to permit an aeration subassembly to lift off the ground when an aeration tine impacts a hard obstacle such as a rock in the soil. The weight transferring systems may in the preferred embodiments be calibrated so that only minimal upward force, such as that caused by impact of an aeration tine with a rock, may cause the aeration subassembly to lift thereby significantly reducing or preventing damage to the aeration tines and drive assemblies and substantially prolonging the life of the aerator. ## Claims ### Claim 1 A soil aerator, comprising: a frame assembly having a front end and a rear end; an aeration device coupled to the frame assembly; a front axle member to support the frame assembly, the front axle member located forward of the aeration device; a rear axle member to support the frame assembly, the rear axle member located aft of the aeration device; a weight transfer system coupled to the frame assembly, the weight transfer system having a biasing member that applies a moment to the frame assembly to transfer a portion of the frame assembly and aeration device's combined weight to the front axle member or the rear axle member, wherein the frame assembly is hinged and the aeration device is urged about the hinge axis by the weight transfer system. ### Claim 2 (depends on 1) The soil aerator of claim 1, wherein the front axle member is coupled to a roller. ### Claim 3 (depends on 2) The soil aerator of claim 2, further comprising a second rear axle member and wherein each rear axle member is coupled to a wheel. ### Claim 4 (depends on 1) The soil aerator of claim 1, wherein the weight transfer system includes a first spring member coupled to the frame assembly. ### Claim 5 (depends on 4) The soil aerator of claim 4, wherein the weight transfer system further includes a second spring member coupled to the rear axle member and the frame assembly. ### Claim 6 (depends on 1) The soil aeration of claim 1, wherein the weight transfer system is adapted to transfer a variable fraction of the weight of the aeration device to at least one of the front axle member and the rear axle member such that a head weight of the aeration device can be varied. ### Claim 7 (depends on 1) The soil aerator of claim 1, comprising at least two rear axle members each coupled to the frame by a separate suspension system. ### Claim 8 (depends on 1) The soil aerator of claim 1, wherein the weight transfer system includes at least two spring members that apply opposite moments to the frame assembly. ### Claim 9 (depends on 1) The soil aerator of claim 1, wherein the weight transfer system includes a constant force spring. ### Claim 10 (depends on 1) The soil aerator of claim 1, wherein the aeration device includes a planetary gear system to rotate and translate a plurality of tine shafts bearing aeration tines. ### Claim 11 (depends on 10) The soil aerator of claim 10, wherein each aeration tine includes an arcuate soil fracturing edge. ### Claim 12 A soil aerator, comprising: a frame assembly having a front end and rear end; means for aerating soil coupled to the frame assembly; front support means to support the frame assembly as it travels across a ground surface, the front frame support means located forward of the aerating means; rear support means to support the frame assembly as it travels across the ground surface, the rear support means located aft of the aerating means; weight transfer means for applying a moment to the frame assembly, the weight transfer means including a biasing means that applies a moment to the frame assembly to transfer a portion of the combined weight of the frame assembly and the aerating means to the front support means or the rear support means, wherein the frame assembly is hinged and the aerating means is urged about the hinge axis by the weight transfer means. ### Claim 13 (depends on 12) The soil aerator of claim 12, wherein the front support means includes a roller. ### Claim 14 (depends on 13) The soil aerator of claim 13, wherein the rear support means comprises at least two rear axle members and wherein the rear axle members are coupled to separate wheels. ### Claim 15 (depends on 12) The soil aerator of claim 12, wherein the weight transfer means includes a first spring member coupled to the frame assembly. ### Claim 16 (depends on 15) The soil aerator of claim 15, wherein the weight transfer means further includes a second spring member coupled to the rear support means and the frame assembly. ### Claim 17 (depends on 12) The soil aerator of claim 12, wherein the weight transfer means is adapted to transfer a variable fraction of the weight of the aerating means to the front support means or the rear support means such that a head weight of the aerating means can be varied. ### Claim 18 (depends on 12) The soil aerator of claim 12, comprising at least two rear axle members each coupled to the frame assembly-by a separate suspension system. ### Claim 19 (depends on 12) The soil aerator of claim 12, wherein the weight transfer means includes at least two spring members that apply opposite moments to the frame assembly. ### Claim 20 (depends on 12) The soil aerator of claim 12, wherein the aerating means includes a planetary gear system to rotate and translate a plurality of tine shafts bearing aeration tines. ### Claim 21 (depends on 20) The soil aerator of claim 20, wherein each aeration tine includes an arcuate soil fracturing edge. ### Claim 22 A soil aerator, comprising: a frame assembly having a front end and a rear end; an aeration device coupled to the frame assembly; a front axle member to support the frame assembly, the front axle member located forward of the aeration device; a rear axle member to support the frame assembly, the rear axle member located aft of the aeration device; a weight transfer system coupled to the frame assembly, the weight transfer system having a biasing member that applies a moment to the frame assembly to transfer a portion of the frame assembly and aeration device's combined weight to the front axle member or the rear axle member, wherein the weight transfer system includes a constant force spring.