US3867987A

US3867987A - Vibratory bulldozer blade

Info

Publication number: US3867987A
Application number: US378869A
Authority: US
Inventors: David H Seaberg
Original assignee: JI Case Co
Current assignee: Case LLC
Priority date: 1973-07-13
Filing date: 1973-07-13
Publication date: 1975-02-25
Anticipated expiration: 1992-02-25
Also published as: CA1002753A

Abstract

A vibratory plow for bulldozers and the like, having a blade supported on two fixed pivot axes and a vibrator connected to the blade between the pivot axes. The disclosed plow includes a boxlike moldboard enclosure supported in transverse relation on a vehicle, such as a bulldozer, and a blade having a lower cutting edge and a plurality of resiliently flexible arms extending upwardly within the moldboard enclosure and supported on the fixed pivot axes. The vibrator resiliently flexes the arms about the fixed axes, preferably within the natural or resonate frequency of the blade.

Description

nite States Patent [191 Seaberg [451 Feb. 25, 1975 VIBRATORY BULLDOZER BLADE [75] Inventor: David H. Seaberg, Davenport, Iowa [73] Assignee: J. 1. Case Company, Racine, Wis.

[22] Filed: July 13, 1973 [21] Appl. No.: 378,869

[52] US. Cl. 172/40, 172/802 [51] Int. Cl A01b 35/32 [58] Field of Search 172/802, 40, 101, 108,

[56] References Cited UNITED STATES PATENTS 11/1969 Cunningham 172/40 X 9/1970 Den Bleyker 172/802 2/1971 Fryrear 172/802 Primary ExaminerStephen C. Pellegrino Attorney, Agent, or Firm-Cullen, Settle, Sloman & Cantor [57] ABSTRACT A vibratory plow for bulldozers and the like, having a blade supported on two fixed pivot axes and a vibrator connected to the blade between the pivot axes. The disclosed plow includes a box-like moldboard enclosure supported in transverse relation on a vehicle, such as a bulldozer, and a blade having a lower cutting edge and a plurality of resiliently flexible arms extending upwardly within the moldboard enclosure and supported on the fixed pivot axes. The vibrator resiliently flexes the arms about the fixed axes, preferably within the natural or resonate frequency of the blade.

25 Claims, 4 Drawing Figures 1 VIBRATORY BULLDOZER BLADE FIELD OF THE INVENTION ciprocating the blade of an earth working tool has long been recognized and. various means have been suggested to vibrate the blade. For example, the prior art includes reciprocating plows wherein the upper edge of the blade is pivotally supported and the lower edge is reciprocated or vibrated by mechanical means to reduce the required tractive force. Pneumatic and electric vibrators have also been suggested by the prior art for bulldozer plow blades.

In a transverse plow blade, however, the energy re quired to vibrate or reciprocate the bulldozer blade may off-set the advantages. In an effort to reduce the energy required for such vibratory plows, the prior art has suggested that the amplitude of vibration is preferably the natural or resonate frequency of the blade. When the resonate frequency is achieved, the required energy is substantially reduced. The problem has been to design a vibratory plow, particularly a transverse plow, wherein resonate frequency can be achieved in the blade.

SUMMARY OF THE INVENTION The plow blade in the vibratory plow of this invention includes a relatively rigid lower cutting edge portion and a plurality of separate, upwardly extending resilient arms integral with the lower edge portion. The arms include a first common fixed pivot adjacent the upper distal ends and a second common fixed pivot spaced between the first pivot and the lower edge portion. In the preferred embodiment, the blade is supported on a moldboard, generally transverse to the axis of the supporting vehicle. The moldboard in the disclosed embodiment is a box-like enclosure having side walls which support the blade.

The vibrator is connected to theblade arms between the first and second pivot axis and resiliently flexes the blade arms about the fixed pivot axes" to vibrate the lower cutting edge, preferably within the resonate frequency of the blade. In the disclosed embodiment, the vibrator includes a fluid cylinder supported on the rear wall of the moldboard, a reciprocating piston and a piston rod pivotally connected to the blade. The disclosed embodiment includes a vibrator connected to each of the resilient blade arms. A frequency control and valve is provided, connected to a source of fluid pressure and the fluid cylinder, which controls the amplitude of vibration by controling the fluid into and out of the cylinder.

An object of the present invention is to reduce the power input to the vibrator by adjusting the frequency control to achieve resonate frequency of the blade. The resonate or natural frequency will also change with the conditions of use, including temperature, soil conditions and the like. In the disclosed embodiment, the arms are resiliently flexible, permitting flexure of the arms, and the lower cutting edge is relatively rigid, permitting vibration of the blade without reducing the structural requirements of the cutting edge.

Other advantages and meritorious features of the disclosed invention will be more fully understood from the following description of the preferred embodiment, the drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation ofa bulldozer having the im proved vibratory plow of this invention;

FIG. 2 is a top elevation of the vibratory plow shown in FIG. 1;

FIG. 3 is a front view of the vibratory plow shown in FIGS. 1 and 2; and

FIG. 4 is a cross-sectional view of the vibratory plow shown in FIG. 3, in the direction of view arrows 4-4, including a circuit diagram of the hydraulic control.

DESCRIPTION OF THE PREFERRED EMBODIMENT shown in FIG. 1. The disclosed embodiment of the vibratory plow is mounted in a box-like moldboard enclosure 24 on the push arms 26 of a conventional bulldozer. The moldboard is pivotally supported on the push arms by pivotal connections 28. The push arms are supported on the bulldozer by lift cylinders 30 having a cylinder rod 32 connected to the pivotal connection 28. Tilt cylinders 34 are also connected to the moldboard 24 by rod 32 pivotally connected to the moldboard at 38. The tilt cylinder is pivotally connected to the push arms 26 at 40. It is understood that the vibratory plow of this invention is not limited to the bulldozer construction shown in. FIG. 1 and that the bulldozer 20 is shown for illustrative purposes only.

The vibratory plow shown in FIG. 1 includes a vibratory blade 44 having a cutting edge substantially continuous with the plow face 50 of the moldboard 24 and a vibratory 46 on the rearward wall of the moldboard. The details of the disclosed embodiment of the vibratory plow of this invention are best shown in FIGS. 2

to 4, wherein FIG. 4 includes the hydraulic circuit 88 of the vibrator 46.

As shown in FIG. 4, the moldboard enclosure 24 includes a forward plow face 50, side walls 52, top and

bottom walls

54 and 56 respectively and a rearward wall 58 opposed to the plowface 50. The moldboard in the preferred embodiment encloses the vibratory plow blade 44, as described below.

The vibratory blade 44 includes a relatively rigid lower end or edge 62 and a plurality of upwardly extending resilient arms 64, as shown in FIGS. 3 and 4. A separate cutting edge or plate 66 is secured to the lower end 62 of the blade by screws 68 or other suitable means including welding. The blade is supported within the moldboard enclosure by an upper pivot rod 70 extending through the upper distal ends of the arms and secured to the side walls 52 of the moldboard as shown in FIG. 3. A second pivot rod 72 extends through the arms 64 below the mid-portion of the blade, as shown in FIG. 4, which is secured to the side walls 52 of the moldboard as shown in FIG. 3. The upper and lower pivot rods, 70 and 72, define fixed pivot axes for the resilient blade arms as described hereinbelow. The blade is preferably curved or arcuate, as shown in FIG. 4, having a reduced width at 74 to provide additional resiliency. An enlarged end portion is defined around the pivot rod 70 to provide additional strength.

The vibrators 46 in the disclosed embodiment include a fluid or hydraulic cylinder 78, as shown in FIG.

4, apiston 80 slidingly disposed within the cylinder the reciprocating motion and a piston rod 82 connected to the blade between the upper and

lower pivot axes

70 and 72. In the disclosed embodiment, a separate vibrator 46 is provided for each of the blade arms 46, as shown in FIG. 2, and each of the piston rods 82 are pivotally connected to an arm 64 by pivotal connection 84, as shown in FIG. 4. Each of the arms are provided with a boss 86 which may be bifurcated to receive the pivot rods, as shown.

It will be seen from FIG. 4 that reciprocating motion of the piston rods 82 resiliently flexes the arms 64 of the blade, vibrating the cutting'edge 66, as shown in phantom at 67. In the preferred embodiment, the amplitude of vibration is adjusted to the harmonic or natural frequency of the blade, substantially reducing the required power input. The frequency of vibration is controlled by the hydraulic circuitry 88 shown diagrammatically in FIG. 4.

The control circuit for the vibrator 46 in the disclosed embodiment includes an electro-hydraulic control valve 90 connected by

lines

92 and 94 to the opposed sides of the piston 80. The control valve 90 is adapted to pulsate the fluid entering and leaving the cylinder 78 to vibrate the piston rods 82 and blade arms 64 in a controlled frequency. A suitable electrohydraulic control valve is manufactured by Moog, Inc. and identified as a Series 72 Flow Control Servo Valve. Other suitable valves may also be utilized. The Moog Series 72 Control Valve is a pilot operated closed center four-way sliding spool valve, wherein the output flow to the constant load is proportional to the electrical input current. The valve preferably includes an electric torque motor.

The control valve 90 is connected to a suitable pump 96 through line 98 and a source of hydraulic fluid, such as a reservoir 100, through line 102. A suitable pump is a pressure compensated pump, such as sold by Vickers, Division of Sperry-Rand Corporation. A pressure compensated pump is a piston pump with a constant pressure output, such as VickerDivision pump, P15.

Other suitable pressure compensated pumps may also be utilized.

In the disclosed embodiment, a frequency control 104 is provided and connected to valve 90 through the line 106. Any suitable frequency control may be utilized, such as a rheostat-type control.

In the disclosed hydraulic circuit, the pump 96 delivers fluid pressure from reservoir 100 to valve 90 which controls the fluid input and output to the cylinder 78 through

lines

92 and 94. The output from the cylinder is delivered to the valve through line 92 and from the valve to the reservoir through line 102. As will be understood by those skilled in the art, the amplitude of vibration may be controlled by adjusting the control 104. The amplitude may be separately adjusted by adjusting the amplitude of the pulsations to the hydraulic cylinder 78. The frequency control would normally be mounted on the bulldozer control panel, permitting the operator to adjust the amplitude of vibration, preferably within the natural or resonate frequency of the blade. The resonate frequency will be known to the operator by the power requirements for vibration. The power input is minimal at the resonate frequency, however the natural or resonate frequency may change with the conditions. For example, the resonate frequency will be dependent upon the temperature of the blade, the conditions of the soil and the depth of the cut. In the preferred embodiment, therefore, the amplitude of vibration may be adjusted to within the natural or resonate frequency by adjusting the frequency control 104 provided on the operators control panel.

The vibrators 46 in the disclosed embodiment are preferably connected in parallel to the control circuit 88, as shown, to vibrate in the same frequency, which is preferably the natural frequency of the blade. The reciprocating motion of the piston rods 82 resiliently flex the blade arms 64 about the common fixed axes and 72, as shown in FIG. 4. When the resonate frequency is achieved, the resilient arms vibrate similar to a tuning fork, vibrating the lower edge 62 and the cutting edge 67. The lower edge is relatively rigid to permit plowing with the blade, and the arms, which are preferably integral with the blade edge, are relatively flexible. A suitable material for the blade is a high carbon, heat treated steel, such as SAE 8620. Other materials may also be utilized having the requisite strength and flexibility.

It will be understood that other means may be utilized to vibrate the blade, provided the vibrators are connected between the fixed pivot axes 70 and 72. F urther, a single vibrator may be utilized to vibrate the arms, wherein the vibrator is connected to a common pivotal connection to the arms between the fixed pivot axes 70 and 72. The moldboard enclosure 24 is provided to protect the resilient vibrating arm 64 and to prevent build-up of dirt and debris. The bottom wall 56 or rear wall 58 of the moldboard enclosure would normally be provided with apertures to permit the escape of water and other contaminants or the bottom of the moldboard may be open. The rearward wall 58 of the moldboard supports the vibrators and provides the base for vibration. The moldboard is supported on the push arms 26 of the bulldozer 20, as shown in FIG. 1. It will be understood, however, that the moldboard may be modified depending upon the conditions of use.

In the disclosed embodiment, the moldboard 24 is enclosed and includes a plurality of transverse slots 108 in the forward wall '50 adjacent the lower end, as shown in FIG. 3. The plow may be assembled by inserting the arm 64 of the blade within the slots and securing the arms by

pivot rods

70 and 72. The blade is removed by simply releasing the

rods

70 and 72 and disconnecting the piston rods. The lower end 62 of the blade and cutting edge 66 is then supported against the moldboard, between the slots 108. The disclosed embodiment of the moldboard and the blade assembly is therefore relatively simple in design and provides several advantages in the vibratory plow of this invention.

I claim:

1. A vibratory plow, comprising, in combination, a plow blade having a relatively rigid lower cutting edge portion and a plurality of separate, upwardly extending resilient arms integral with said lower edge portion, a structural support on opposed sides of said blade pivotally supporting said arms on first and second common fixed pivot axes, said first common fixed pivot axis located adjacent the upper distal ends of said arms and said second common fixed pivot axis spaced between said first pivot axis and said lower blade edge portion, and a vibrator means connected to said blade between said first and second blade pivot axes adapted to vibrate said arms and said lower cutting edge portion about said common axes.

2. The vibratory plow defined inclaim 1, characterized in that said support comprising a moldboard having an upper plow face substantially continuous with said lower edge portion of said blade and said moldboard supported in transverse relation on a vehicle.

3. The vibratory plow defined in claim 2, characterized in that said moldboard includes side walls structurally supporting said blade on said fixed pivot axes.

4. The vibratory plow defined in claim 3, characterized in that said first pivot axis comprises a rod disposed through said arms and secured to said moldboard side walls.

5. The vibratory plow defined in claim 4, characterized in that saidsecond pivot axis comprises a rod disposed through said arms and secured to said moldboard side walls below the mid-portion of said blade, and said vibrator means connected to said arms adjacent said mid-portion of said blade.

6. The vibratory plow defined in claim 5, characterized in that said moldboard includes a back wall opposed to said plow face and enclosing said blade arms.

7. The vibratory plow defined in claim 6, characterized in that said vibrator means includes a fluid pressure cylinder having a fluid cylinder supported on said moldboard back wall and a piston having a rod pivotally connected to said blade.

8. The vibratory plow defined in claim 7, characterized in that each of said resilient blade arms includes a separate vibrator means.

9. The vibratory plow defined in claim 2, characterized in that said moldboard is a box-like enclosure, including a rearward wall opposed to said plow face and side walls enclosing said blade arms, said moldboard having a plurality of spaced elongated slots generally parallel to said blade cutting edge receiving said arms within said moldboard.

10. The vibratory plow defined in claim 1, characterized in that said vibrator means includes a fluid pressure cylinder connected to said support for said blade and a piston rod pivotally connected to said blade and a frequency control means connected to said cylinder and a source of fluid pressure, said control means adapted to adjust the amplitude of vibration of said blade to within the natural frequency of said blade.

11. A vibratory plow, comprising, in combination, a moldboard supported on a vehicle, a plow blade having a lower edge and a plurality of resilient, relatively flexible arms integral with said lower blade edge and extending upwardly from said lower edge is spaced relation, said blade structurally supported on said moldboard on two spaced fixed pivot axes, including a first pivot axis adjacent the upper distal end of said arms and a second pivot axis spaced below the mid-portion of said arms, and a vibrator means connected to said arms near said mid-portion of said blade and between said first and second pivot axes, said vibrator means adapted to resiliently flex said blade about said fixed pivot axes and vibrate said lower blade edge.

12. The vibratory plow defined in claim 11, characterized in that said moldboard has side walls, and said fixed pivot axes including two rods extending through said arms and supported on said moldboard side walls.

13. The vibratory plow defined in claim 11, characterized in that said moldboard is a box-like enclosure supported on said vehicle in transverse relation, and said blade arms are supported within said moldboard enclosure.

14. The vibratory plow defined in claim 13, characterized in that said moldboard includes an upper plow face substantially continuous with said blade lower edge and a plurality of-transverse slots receiving said blade arms and supporting said lower edge.

15. The vibratory plow defined in claim 14, characterized in that said vibrator means includes a fluid pressure cylinder supported on the rearward wall of said moldboard and a fluid piston having a piston rod pivotally connected to said plow blade arms.

16. The vibratory plow defined in claim 13, characterized in that each of said arms has a vibrator means, comprising a plurality of fluid pressure cylinders supported on the rearward moldboard wall, opposite each of said arms and a piston disposed within each of said cylinders for reciprocating motion, said pistons each having a piston rod pivotally connected to one of said blade arms.

17. The vibratory plow defined in claim 15, characterized in said vibrator means having a frequency con trol means connected to said fluid pressure cylinder and a source of fluid pressure, said control means adapted to adjust the amplitude of vibration to within the resinate frequency of said blade.

18. A vibratory plow, comprising, in combination, an enclosed box-like moldboard having a forward plow face and supported on a vehicle generally transverseto the axis of said vehicle, a plow blade having a lower cutting edge substantially continuous with said moldboard plow face and a plurality of resilient, upwardly extending arms within said moldboard enclosure structurally supported on said moldboard on two fixed axes generally parallel to said plow face, including a first axis adjacent the distal ends of said arms and a second axis below the mid-portion of said blade, said moldboard having a plurality of slots receiving said arms therethrough and said moldboard supporting said cutting edge between said slots, and a. vibrator means connected to said resilient arms, adjacent said mid-portion of said blade, between said first and second axes, resiliently flexing said blade within its harmonic frequency to vibrate said cutting edge.

19. The vibratory plow defined in claim 18, characterized in said vibrator means having a fluid cylinder, connected to said moldboard, a piston reciprocally supported within said cylinder and a piston rod pivotally connected to said blade, and a frequency control means connected to said cylinder and a source of fluid pressure adapted to vary the amplitude of vibration of 'said blade within said harmonic frequency.

20. The vibratory plow defined in claim 19 characterized in that each of said blade arms includes a fluid pressure cylinder connected to said moldboard, piston and piston rod pivotally connected to each of said arms.

21. The vibratory plow defined in claim 19 characterized in said fluid cylinders supported on said moldboard on a wall opposed to said plow face.

22. The vibratory plow defined in claim 18, characterized in that said plow blade is arcuate having an axis of curvature generally parallel to said cutting edge forward of said plow face.

23. The vibratory plow defined :in claim 22, characterized in said plow blade having a reduced thickness between said first and second fixed axes.

24. The vibratory plow defined in claim 22, characterized in that said fixed blade axes each comprising a terized in said plow blade arms having a thickness less rod disposed through said arms and supported on the then the thickness of said cutting edge. side walls of said box-like moldboard enclosure.

25. The vibratory plow defined in claim 18, charac-

Claims

2. The vibratory plow defined in claim 1, characterized in that said support comprising a moldboard having an upper plow face substantially continuous with said lower edge portion of said blade and said moldboard supported in transverse relation on a vehicle.

5. The vibratory plow defined in claim 4, characterized in that said second pivot axis comprises a rod disposed through said arms and secured to said moldboard side walls below the mid-portion of said blade, and said vibrator means connected to said arms adjacent said mid-portion of said blade.

14. The vibratory plow defined in claim 13, characterized in that said moldboard includes an upper plow face substantially continuous with said blade lower edge and a plurality of transverse slots receiving said blade arms and supporting said lower edge.

17. The vibratory plow defined in claim 15, characterized in said vibrator means having a frequency control means connected to said fluid pressure cylinder and a source of fluid pressure, said control means adapted to adjust the amplitude of vibration to within the resinate frequency of said blade.

18. A vibratory plow, comprising, in combination, an enclosed box-like moldboard having a forward plow face and supported on a vehicle generally transverse to the axis of said vehicle, a plow blade having a lower cutting edge substantially continuous with said moldboard plow face and a plurality of resilient, upwardly extending arms within said moldboard enclosure structurally supported on said moldboard on two fixed axes generally parallel to said plow face, including a first axis adjacent the distal ends of said arms and a second axis below the mid-portion of said blade, said moldboard having a plurality of slots receiving said arms therethrough and said moldboard supporting said cutting edge between said slots, and a vibrator means connected to said resilient arms, adjacent said mid-portion of said blade, between said first and second axes, resiliently flexing said blade Within its harmonic frequency to vibrate said cutting edge.

19. The vibratory plow defined in claim 18, characterized in said vibrator means having a fluid cylinder, connected to said moldboard, a piston reciprocally supported within said cylinder and a piston rod pivotally connected to said blade, and a frequency control means connected to said cylinder and a source of fluid pressure adapted to vary the amplitude of vibration of said blade within said harmonic frequency.

23. The vibratory plow defined in claim 22, characterized in said plow blade having a reduced thickness between said first and second fixed axes.

24. The vibratory plow defined in claim 22, characterized in said plow blade arms having a thickness less then the thickness of said cutting edge.

25. The vibratory plow defined in claim 18, characterized in that said fixed blade axes each comprising a rod disposed through said arms and supported on the side walls of said box-like moldboard enclosure.