US3703127A - Rigid base earth compactor - Google Patents

Rigid base earth compactor Download PDF

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Publication number
US3703127A
US3703127A US98328A US3703127DA US3703127A US 3703127 A US3703127 A US 3703127A US 98328 A US98328 A US 98328A US 3703127D A US3703127D A US 3703127DA US 3703127 A US3703127 A US 3703127A
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weight
weights
compacting machine
earth
base plate
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US98328A
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English (en)
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Benno Kaltenegger
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    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D3/00—Improving or preserving soil or rock, e.g. preserving permafrost soil
    • E02D3/02—Improving by compacting
    • E02D3/046—Improving by compacting by tamping or vibrating, e.g. with auxiliary watering of the soil
    • E02D3/074—Vibrating apparatus operating with systems involving rotary unbalanced masses

Definitions

  • impacts exerted on the earth by this machine have a complex waveform, including a band of frequencies which provide for optimum compacting of earth of various particle sizes and consistencies.
  • the slower rotating weight has a greater mass than the faster rotating weight.
  • the portion of the base associated with the slower rotating heavier weight is heavier than the portion of the base associated with the lighter faster rotating weight.
  • Earth compacting machine in which a base or base plate is vibrated by an unbalanced shaft carrying eccentrically mounted weights are known in the art. Usually, such machines have a single vibrator and a base plate with a relatively small compacting area.
  • the present invention relates to an earth compacting machine in which the base of the machine is in one piece and has at least two shafts each provided with an unbalanced eccentric weight.
  • the base takes the form of a shell or plate having two con vex bottom surface portions, one adjacent the other in the longitudinal direction of the machine, and an unbalanced weight is associated with each convex surface.
  • the base provides a high specific surface pressure even though the area of the base is large.
  • the high surface pressure is provided in part by the convex bottom surfaces of the base plate. These convex surfaces are arranged one after the other in the longitudinal direction of the machine and correspond in number to the number of shaft and weight assemblies on the rigid base.
  • earths of different consistencies and types should be compacted at different vibrational frequencies for optimum compacting efficiency.
  • gravel is most efficiently compacted at a different vibrational frequency from soft loamy soil.
  • one to compact gravel for example, and one to compact soft loamy soil.
  • only one machine is required because the machine produces a wide band of frequencies within predetermined limits and these frequencies are constantly repeated. Since these different frequencies occur repeatedly, and since different earth particle sizes respond differently to different vibrational frequencies, substantially all the particle sizes in the earth are vibrated and compacted with equal efficiency.
  • earths of different consistencies are compacted as efficiently as if an optimum frequency were selected for compacting the particular earth.
  • a single machine in accordance with this invention is suitable for compacting earth of various consistencies with the same optimum operating action.
  • optimum vibrational and impacting characteristics are attained by rotating the weights at different rotational speeds relative to each other to provide frequencies and amplitudes for optimum compacting action.
  • the construction of the earth compacting machine of the invention is such that even though the 'base plate is rigid and of unitary construction, the individual convex surface portions of the base plate are subjected to vibrations of different frequencies. Such vibrations are transmitted to the earth through the associated bottom surface portion of the base. For example, if one weight is rotated to vibrate at a frequency of 60 cycles per second and the other weight is rotated to vibrate at cycles per second, the result is that one convex bottom surface impacts the earth with the lower primary frequency. By rotating one shaft so its associated weight vibrates at one frequency, and rotating another shaft so its associated weight vibrates at a different frequency, but related to the first frequency, the vibrational impacts on the earth are displaced from each other in time but occur in a predetermined sequence.
  • the shafts and the associated unblanced or eccentric weights are so selected as to provide the desired frequency ranges.
  • the weight on one shaft can be heavier than the weight on another shaft and the heavier weight will be rotated at a speed so its frequency of vibration is lower than the frequency of vibration of the shaft with the lighter weight.
  • the shaft with the lower frequency larger weight can be associated with a heavier bottom surface portion of the base with, for example, the ratio of the mass of the heavier bottom surface to the mass of the lighter bottom surface in the same ratio as the mass of the larger weight to the mass of the smaller weight.
  • the intensity of the vibration from either the high frequency weight or the low frequency weight can be carefully regulated.
  • the proper frequency range for the earth to be compacted can be obtained quite simply by varying the mass of the weights, changing the rotational speed of the weights, or using base portions in which the convex surfaces are of different mass.
  • FIG. 1 is a diagrammatic partial sectional view in side elevation showing one embodiment of earth compacting machine according to this invention
  • FIG. 2 is a partial view corresponding to FIG. 1 and showing a different embodiment
  • FIG. 3 is a view corresponding to FIG. 2 and showing another embodiment of the invention.
  • FIGS. 4-7 are diagrammatical views in side elevation showing the respective positions of the unbalanced weights relative to each other during a complete cycle of rotation of one of the weights for a particular embodiment of the invention.
  • earth compacting machine 1 includes a unitary one piece base member or plate 2 on which a common frame 4 of the machine is supported and which frame is mounted on the base by sets of springs 5 and 6 adjacent opposite ends of base 2.
  • base 2 mounted on base 2 are two vibrating assemblies 7 and 8.
  • Assembly 7 includes a shaft 9 journalled for rotation on the base and to which an eccentrically mounted weight 11 is fixed so it rotates with the shaft.
  • Assembly 8 includes a shaft 10 also journalled for rotation on the base and to which an eccentrically mounted weight 12 is fixed so it rotates with the shaft.
  • the weights 11 and 12 have the same mass, shafts 9 and 10 are parallel, and the shafts 9 and 10 extend transversely of the machine.
  • the drive arrangement includes a pulley 14 keyed to the motor shaft, and a pulley l5 keyed to shaft 9, and a drive belt 16 which extends around the pulleys.
  • a spring loaded belt tensioning device 19, mounted on frame 4 engages the belt 16 and maintains proper tension in the belt even though base 2 vibrates relative to frame 4 and the motor 13.
  • Shaft 10 is driven by shaft 9.
  • the drive includes a drive belt extending around a pulley a keyed to shaft 9 and a pulley 18 keyed to shaft 10.
  • pulley 18 has a larger diameter than pulley 15a so shaft 10 and its associated weight 12 rotate at a slower speed than shaft 9 and its associated weight 11.
  • the diameter of pulley 15a is one-half the diameter of pulley 18 and correspondingly, shaft 9 rotates at a speed which is twice the speed of rotation of shaft 10.
  • weights 1] and 12 are 90 out of phase and hence, the vibrational forces of the weights do not act in the same direction. Because weight 12 rotates at half the speed of weight 11, the frequency of vibration of assembly 8 is half the frequency of vibration of assembly 7.
  • Base 2 is advantageously formed from metal such as cast iron or steel and takes the form of a rigid one piece shell. As shown at FIG. 1, the base has a pair of curved bottom portions each integral with the base which provide downwardly facing convex bottom surfaces 3a and 3b arranged one after the other in the longitudinal or fore and aft direction of the earth compacting machine. Convex surfaces 3a and 3b are each arcuately curved as viewed in side elevation at FIG. 1, and are elongated in a direction transeversely of the machine so each surface is cylindrical. Convex surface 30 is associated with.
  • vibration assembly 7 whereas convex surface 317 is associated with vibration assembly 8.
  • the axis 21 of the center of curvature of surface 3a is perpendicular to a vertical line 22 perpendicular to the axis of shaft 9.
  • the axis 23 of the center of curvature of convex surface 3b is perpendicular to a vertical line 24 perpendicular to the axis of shaft 10.
  • the axes 21 and 23 are above the axes of rotation of the respective shafts 9 and 10 so the machine 1 has a low profile.
  • the portion of base 2 on which surface 3a is formed is essentially the mirror image of the portion of the base on which surface 3b is formed, these portions are of essentially the same radius of curvature and have the same wall thickness, and correspondingly, these portions are of essentially equal mass and weight.
  • the embodiment of the invention shown at FIG. 2 is basically similar to that of FIG. 1 since the bases 2 are identical.
  • the eccentric or unbalanced weight on the shaft 10 of the embodiment of FIG. 2 is heavier than the weight 12 on the shaft 10 of the embodiment of FIG. 1.
  • each weight could in fact be a plurality of weights spaced along the respective shafts 9 and 10.
  • the heavier weight 12 is rotated at a lower speed than the lighter weight 11, and correspondingly, the frequency of vibration of the vibration assembly including shaft 10 and weight 12a is lower than the frequency of vibration of the assembly including shaft 9 and weight 11.
  • weight 12a is of a greater mass than the weight 11, the amplitude or force of vibration resulting from the rotation of weight 12a is greater than the amplitude or force of vibration resulting from the rotation of weight 11.
  • the embodiment of FIG. 3 includes the weight 12a explained with regard to FIG. 2.
  • a convex surface 3a on one portion of the base identical to the convex surface 3a previously explained for the embodiments of FIGS. 1 and 2.
  • a convex surface 3c is formed on a portion of the base, of greater thickness than the portion of the base on which surface 3b is formed.
  • the heavier slower rotating weight 12a on the shaft 10 vibrates the heavier portion of the base on which surface 3c is formed, whereas, the lighter weight 1 1 rotatable with shaft 9, vibrates the lighter portion of the base on which the surface 3a is formed, but at a higher frequency.
  • heavier springs 6 can be used on the portion of the base 3c to support the machine frame 4.
  • the ratio of the speed of rotation of the shafts 9 and 10 can be any desired value most suitable for the conditions of the earth to be compacted.
  • weight 12a could of course be of smaller mass than weight 11 without departing from the contemplated scope of this invention.
  • FIGS. l-3 show only two vibrating assemblies 7 and 8 associated with the respective convex surfaces 3a and 3b
  • additional vibrating assemblies each associated with an additional portion of the base on which a convex surface is formed can also be provided.
  • These additional convex surfaces will, of course be rigid with the base portions on which surfaces 3a and 3b are formed.
  • the base is formed with portions having, for example, three convex surfaces
  • one of the surfaces can be on a portion of the base with a wall thickness like that on which surface 3a is formed
  • another surface can be on a thicker wall portion like that on which surface 3c is formed
  • the third portion of the base could have a wall portion that is even thicker than the wall portion for surface 30.
  • shafts 9 and 10 each rotate in a clockwise direction.
  • FIGS. 4-7 the preferred rotational displacement of the weights will now be explained.
  • weight 11 which has the smaller mass, and weight 12a which has the larger mass simultaneously occupy positions wherein the center of gravity of these weights are directly above or on top of the respective axes of the shafts 9 and 10.
  • shaft 9 rotates at a speed which is twice the speed of rotation of shaft 10.
  • weight 12a has only rotated 90 so its center of gravity is directly to the right of the axis of shaft 10.
  • speed ratios between shafts 9 and 10 in addition to the ratio of 2:] previously described, may be 3:1 or 4:1 or virtually any integer ratio. It will also be appreciated that ratios of 1:2, 1:3 etc, in the speed ratio of shafts 9 and 10 will also provide similar advantages.
  • convex surface 30 is not vibrated at precisely the same frequency of vibration as vibration assembly 7, and surface 3b is not vibrated at precisely the same frequency of vibration as vibration assembly 8. Instead, some of vibration from vibration assembly 8 is received by the surface 3b of the base.
  • the impacts delivered to the earth by the surface 3a are of a frequency and amplitude which depend in part on the frequency and amplitude of vibration of vibration assembly 7 and depend in part on the frequency and amplitude of vibration of vibration assembly 8.
  • the amplitude and frequency of vibration of the impacts on surface 3b on the earth similarly depend on both the amplitudes and frequencies of vibration of the vibration assemblies 7 and 8. In the case of the embodiment of FIG.
  • each surface vibrates in a range of varying frequencies in a recurring pattern above and below the primary frequency of vibration for the surface, and these varying frequencies provide the frequency and amplitude of impact required to compact soils of varying consistencies with a single machine.
  • varying frequencies occur even though weights l1 and 12a are rotated at constant, although different speeds.
  • a vibratory earth compacting machine including a rigid base plate comprising:
  • said rotating means including drive means for simultaneously rotating said weights in a predetermined periodically recurring pattem such that both weights occupy the same angular position on their respective axes at least once during several revolutions of one of the weights;
  • said weights cooperating to vibrate said first surface of said rigid base plate at frequencies including a band of periodically recurring frequencies; and j. said weights cooperating to vibrate said second surface of said base plate at frequencies including a band of periodically recurring second frequencies different from said first frequencies.
  • a vibratory earth compacting machine according to claim I wherein said first weight is adapted to rotate at an essentially constant speed;
  • said second weight is adapted to rotate at an essentially constant speed which is one-half the speed of rotation of said first weight; and both weights occupy the same vertical position on their respective axes at least once during several revolutions of one of the weights.
  • said first surface of said base plate is convex; said second surface of said base plate is convex; and said second weight has a greater mass than said first weight.
  • said second surface is on a portion of the base plate having a greater mass than the portion of the base plate having said first surface. 5.
  • a vibratory earth compacting machine comprismg:
  • a rigid base plate having a plurality of arcuate convex bottom portions formed in said plate and arranged to contact the earth for compaction, said arcuate portions extending transversely to the machine and being disposed longitudinally with respect to each other, vibrating means mounted on said base plate for vibrating said plate, and said vibrating means being disposed in spaced relation above said arcuate portions.
  • said arcuate portions include a first arcuate portion having a greater mass than a second arcuate portion.
  • said vibrating means includes a first vibrating means and a second vibrating means, said first vibrating means includes a first weight eccentrically mounted for rotation about a first axis, and said second vibrating means includes a second weight eccentrically mounted for rotation about a second axis.
  • said vibrating means includes a first and second vibrating means, and means for operating said second vibrating means at a higher frequency than said-first vibrating means.
  • said vibrating means includes a first vibrating means and a second vibrating means, and means to operate said first and second vibrating means at different frequencies.
  • said first frequency is approximately one-half second frequency. 16.
  • An earth compacting machine wherein said first means includes a first weight mounted eccentrically for rotation; said second means includes a second weight mounted eccentrically for rotation; and said operating means includes means to rotate said weights at different speeds relative to each other. 17.
  • An earth compacting machine according to claim 0 10 wherein said first weight has a mass greater than the mass of said second weight. 18.
  • An earth compacting machine according to claim 17 including means to rotate said second weight at a speed greater than said first weight.
  • An earth compacting machine is mounted on a first shaft; said second weight is mounted on a second shaft; motor means rotates one of said shafts; and drive means between said shafts for rotating said other shaft in response to rotation of said one shaft. 20.
  • An earth compacting machine wherein said weights are rotated and positioned relative to each other such that both weights occupy a top vertical position simultaneously during each complete revolution of one of said weights; whereby, an upwardly directed force simultaneously acts on the portions of the base of both said convex surfaces to provide an unweighting action facilitating movement of the compacting machine.
  • An earth compacting machine including means for rotating one of said weights at a speed which is a multiple of the speed of rotation of the other of said weigths.

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  • Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Soil Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Agronomy & Crop Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Road Paving Machines (AREA)
  • Motorcycle And Bicycle Frame (AREA)
  • Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)
US98328A 1970-01-17 1970-12-15 Rigid base earth compactor Expired - Lifetime US3703127A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19702001987 DE2001987A1 (de) 1970-01-17 1970-01-17 Bodenverdichtungsgeraet

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US3703127A true US3703127A (en) 1972-11-21

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US98328A Expired - Lifetime US3703127A (en) 1970-01-17 1970-12-15 Rigid base earth compactor

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US (1) US3703127A (US08066781-20111129-C00013.png)
JP (1) JPS4835764B1 (US08066781-20111129-C00013.png)
AT (1) AT317967B (US08066781-20111129-C00013.png)
AU (1) AU2272270A (US08066781-20111129-C00013.png)
BE (1) BE760630A (US08066781-20111129-C00013.png)
CA (1) CA954362A (US08066781-20111129-C00013.png)
CH (1) CH525340A (US08066781-20111129-C00013.png)
DE (1) DE2001987A1 (US08066781-20111129-C00013.png)
ES (1) ES386296A1 (US08066781-20111129-C00013.png)
FR (1) FR2075439A5 (US08066781-20111129-C00013.png)
GB (1) GB1310748A (US08066781-20111129-C00013.png)
NL (1) NL7100295A (US08066781-20111129-C00013.png)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3945748A (en) * 1974-05-13 1976-03-23 Compaction Technology (Proprietary) Limited Compaction by superimposing impact forces on a preloaded area of soil
WO1993025762A1 (en) * 1992-06-05 1993-12-23 M-B-W, Inc. Improved drive mechanism for a vibratory compactor
US5387052A (en) * 1993-03-09 1995-02-07 M-B-W Inc. Drive mechanism for a vibratory compactor
EP0854239A2 (de) * 1997-01-17 1998-07-22 BOMAG GmbH Grundplatte für einen Plattenverdichter
US5934825A (en) * 1997-01-28 1999-08-10 Wacker Corporation Vibratory plate machine
WO1999041461A1 (de) * 1998-02-10 1999-08-19 Wacker-Werke Gmbh & Co. Kg Von hand führbare selbstfahrende vibrationsplatte
EP1164223A2 (de) * 2000-06-16 2001-12-19 BOMAG GmbH & Co. OHG Verfahren und Vorrichtung zur Bestimmung des Verdichtungsgrades bei der Bodenverdichtung
US20060283052A1 (en) * 2005-02-11 2006-12-21 Klaus Kremer Snow surface compactor and track apparatus
CN112663446A (zh) * 2020-12-21 2021-04-16 李鹏涛 一种道路施工用路面压平装置

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2001988A1 (de) * 1970-01-17 1971-07-22 Benno Kaltenegger Strassenwalze
JPS5246581U (US08066781-20111129-C00013.png) * 1975-09-30 1977-04-01
DE2802648C2 (de) * 1978-01-21 1984-08-30 Günther Weber Herstellung und Vertrieb von Baumaschinen, 5928 Laasphe In der Marschrichtung umsteuerbare Rüttelplatte

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2453510A (en) * 1945-09-17 1948-11-09 Jackson Vibrators Screeding and compacting machine for concrete slabs and the like
US2643595A (en) * 1947-11-03 1953-06-30 Jackson Corwill Machine for compacting granular mass material
GB944922A (en) * 1959-01-16 1963-12-18 Losenhausenwerk Duesseldorfer Road construction
US3342118A (en) * 1961-05-25 1967-09-19 Beierlein Bernhard Tamping device
US3383992A (en) * 1965-06-26 1968-05-21 Kaltenegger Benno Self-propelled road roller
US3435741A (en) * 1966-12-09 1969-04-01 Bopparder Maschinenbau Gmbh Double vibration roller
US3580147A (en) * 1967-08-25 1971-05-25 Benno Kaltenegger Vibratory road roller

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2453510A (en) * 1945-09-17 1948-11-09 Jackson Vibrators Screeding and compacting machine for concrete slabs and the like
US2643595A (en) * 1947-11-03 1953-06-30 Jackson Corwill Machine for compacting granular mass material
GB944922A (en) * 1959-01-16 1963-12-18 Losenhausenwerk Duesseldorfer Road construction
US3342118A (en) * 1961-05-25 1967-09-19 Beierlein Bernhard Tamping device
US3383992A (en) * 1965-06-26 1968-05-21 Kaltenegger Benno Self-propelled road roller
US3435741A (en) * 1966-12-09 1969-04-01 Bopparder Maschinenbau Gmbh Double vibration roller
US3580147A (en) * 1967-08-25 1971-05-25 Benno Kaltenegger Vibratory road roller

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3945748A (en) * 1974-05-13 1976-03-23 Compaction Technology (Proprietary) Limited Compaction by superimposing impact forces on a preloaded area of soil
WO1993025762A1 (en) * 1992-06-05 1993-12-23 M-B-W, Inc. Improved drive mechanism for a vibratory compactor
US5320448A (en) * 1992-06-05 1994-06-14 M-B-W, Inc. Drive mechanism for a vibratory compactor
US5387052A (en) * 1993-03-09 1995-02-07 M-B-W Inc. Drive mechanism for a vibratory compactor
EP0854239A2 (de) * 1997-01-17 1998-07-22 BOMAG GmbH Grundplatte für einen Plattenverdichter
EP0854239A3 (de) * 1997-01-17 2000-10-04 BOMAG GmbH Grundplatte für einen Plattenverdichter
US5934825A (en) * 1997-01-28 1999-08-10 Wacker Corporation Vibratory plate machine
WO1999041461A1 (de) * 1998-02-10 1999-08-19 Wacker-Werke Gmbh & Co. Kg Von hand führbare selbstfahrende vibrationsplatte
EP1164223A2 (de) * 2000-06-16 2001-12-19 BOMAG GmbH & Co. OHG Verfahren und Vorrichtung zur Bestimmung des Verdichtungsgrades bei der Bodenverdichtung
EP1164223A3 (de) * 2000-06-16 2003-09-17 BOMAG GmbH & Co. OHG Verfahren und Vorrichtung zur Bestimmung des Verdichtungsgrades bei der Bodenverdichtung
US20060283052A1 (en) * 2005-02-11 2006-12-21 Klaus Kremer Snow surface compactor and track apparatus
CN112663446A (zh) * 2020-12-21 2021-04-16 李鹏涛 一种道路施工用路面压平装置

Also Published As

Publication number Publication date
GB1310748A (en) 1973-03-21
JPS4835764B1 (US08066781-20111129-C00013.png) 1973-10-30
BE760630A (fr) 1971-06-21
FR2075439A5 (US08066781-20111129-C00013.png) 1971-10-08
AU2272270A (en) 1972-06-01
DE2001987A1 (de) 1971-07-29
ES386296A1 (es) 1973-03-16
AT317967B (de) 1974-09-25
NL7100295A (US08066781-20111129-C00013.png) 1971-07-20
CH525340A (de) 1972-07-15
CA954362A (en) 1974-09-10

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