US3892079A

US3892079A - Control system for amphibious hydraulic excavator

Info

Publication number: US3892079A
Application number: US318700A
Authority: US
Inventors: Kinichi Hirano; Yoshiaki Metsugi
Original assignee: Hitachi Construction Machinery Co Ltd
Current assignee: Hitachi Construction Machinery Co Ltd
Priority date: 1971-12-27
Filing date: 1972-12-26
Publication date: 1975-07-01
Anticipated expiration: 1992-07-01
Also published as: FR2166032A1; JPS5238323B2; FR2166032B1; JPS4870302A

Abstract

An amphibious hydraulic excavator, comprising an amphibious crawling truck, a revolving platform rotatable on said crawling truck, a shovel assembly mounted on said revolving platform and composed of a boom, arm and bucket, hydraulic actuator means for driving said mentioned parts of the excavator, and a prime mover installed on said revolving platform, characterized in that said mentioned parts are fabricated water-tight while said prime mover being provided with a schnorkel or breathing mast for use of air suction and exhaust, thereby enabling the excavator to be operated under water.

Description

United States Patent Hirano et al. 1 Jul 1, 1975 CONTROL SYSTEM FOR AMPHIBIOUS 3.086.305 4/1963 WBSl 37/71 x HYDRAULIC EXCAVATOR 3.568.454 3/l97l ltami 37/56 X 3,583,585 6/l97l Joyce i 1 1 1 37/103 X [75] Inventors: Kinichi Hirano, Tsuchiura; Yoshiaki 3 59 3 7 1971 v Geuns 37 5 Metsugi, Tokyo. both of Japan 3.631362 1/1972 Fuzzell w i (ill/DIG. 2

. 3.672.725 6/l972 Johnson 1 1 1 i 1 v 37/DlGi 8 [731 Assgnw cmstrucm" Machmery 3.683.521 8/]972 Sloan Cl 111. i i 1 1 1 a M 37/56 -i Japan 3.706,]42 12/1972 Brunner 37/56 [22] Filed: Dec. 26, I972 Primary Examiner-Clifford D. Crowder [2.] Appl' 318700 Attorney. Agent, or Firm-Craig and Antonelli [30] Foreign Application Priority Data 57] ABSTRACT Dec. 27, l97l Japan 46405322 v An amph1b1ous hydraullc excavator. comprlsing an {52] U05 CL M 37/56; 37/71, 37/DIG amphibious crawling truck. a revolving platform rotatolDlG 9H4 91/459. able on said crawling truck, a shovel assembly 34/158 ZI'MDIO mounted on said revolving platform and composed of 511 1m. (:1. E02f 3/32; EOZf 5/28 and buckeh hydraulic actual means Field of Search 37/56. H. DIG. 8, DIG. l; 172/2, 3; 214/DlG. 2, 776, 138 R; 9l/459, 461, 414, 411; 60/DIG. 2; 180/82 R, 98

driving said mentioned parts of the excavator, and a prime mover installed on said revolving platform. characterized in that said mentioned parts are fabricated water-tight while said prime mover being provided with a schnorkel or breathing mast for use of air suction and exhaust, thereby enabling the excavator to be operated under water.

l Claim, 2 Drawing Figures SHEET FIG. 2

lllllll OIL RESERVIOR CONTROL SYSTEM FOR AMPHIBIOUS HYDRAULIC EXCAVATOR BACKGROUND OF THE INVENTION This invention relates to an amphibious hydraulic excavator, and more particularly to an amphibious hydraulic-driven excavating machine such as dozershovel or power-shovel which is capable of operating in water.

When carrying out various operations of excavatingshovelling or loading of the diggings at the bottom of a river or sea-bed especially of small depth of water. it has hitherto been a common practice that by applying the cofferdamming method the specific working area of the river-bed or sea-bed is provisionally dried up so as to enable the ordinary hydraulic excavator to be operated unobjectionably around the dried riveror seabed.

Also, for the working location where the depth of water is comparatively greater. dredgers and the like have been used to grab and bring up sand and mud excavated from the riveror sea-bed by means of a clamshell or such provided on board.

However. in the former method of temporarily damming up a necessary space in the river or sea wherein the hydraulic excavator can be operated. there involves the difficulty that it takes an extended period of time to settle the bottom of river or sea in a dried condition;

while the latter method using a clamshell-equipped boat being highly expensive with respect to necessary equipments.

In consideration of those facts described, it has become an urgent necessity. in the art of excavating and loading operations around the riverand sea-bed. to provide a novel type of hydraulic excavator which can perform its function even in water.

SUMMARY OF THE INVENTION An object of the invention is to obviate the above described prior art defects by providing an amphibious hydraulic excavator which can be unobjectionably operated even in water.

Another object of the invention is to provide an amphibious hydraulic excavator which can be remote radie-controlled.

Still another object is to provide an amphibious hy draulic excavator which makes it possible to practice manual operations by the operator aboard as well as remote radio-control.

The amphibious hydraulic-driven shovel according to the invention comprises: an amphibious crawlermounted truck; hydraulic motors for driving said truck; a revolving platform mounted rotatably on said truck; a further hydraulic motor for rotatingly driving said revolving platform; a shovel assembly consisting of a boom. an arm and a bucket, each being actuated by a respective hydraulic cylinder; at prime mover installed on said revolving platform; hydraulic pumps to be driven by said prime mover for producing necessary pressure fluid; directional control valves for controlling the flows of the pressure fluid to be fed to and for said hydraulic motors and cylinders. respectively; and means for actuating said directional control valves. characterized in that all the parts of the hydraulic excavator are fabricated water-tight while said prime mover being provided with a schnorkel apparatus or breathing mast for use of air suction and exhaust.

The objects and features of the invention will become more apparent by the following description of an embodiment taken in conjunction with the accompanying drawings. wherein:

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a schematic elevation of an amphibious hydraulic excavator of the invention; and

FIG. 2 is a hydraulic circuit diagram showing how the excavator is hydraulically operated according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2. reference numeral I indicates an amphibious crawler-mounted truck; 2 indicates a revolving platform mounted on the truck I for turning movement thereon through a water-tight pintle 3; 4 indicates a boom connected to the revolving platform 2 and adapted for upward and downward swingable movement; 5 indicates an arm provided in connection at the extreme end of said boom 4; 6 indicates a bucket mounted at the extreme end of said arm; 7 and 8 indicate left-and right-side traction hydraulic motors. respectively; 9 indicates a hydraulic motor for driving the revolving platform 2; and

numerals

10, 11 and 12 indicate hydraulic cylinders for actuating the boom 4, arm 5 and bucket 6, respectively. All of the parts described above are driven or actuated by hydraulic pressure.

Numeral 13 indicates an engine room installed on the revolving platform 2. in which room 13 are provided a prime mover l4 and its associated parts including a radiator etc.. all in a water-tight arrangement. 15 indicates a schnorkel or breathing mast extending upwardly from the engine room 13 and it serves as an air intake and exhaust conduit for the prime mover l4. Numeral 17 shows a radio receiver which is stored in a water-tight container 19 provided at the front portion of the revolving platform 2; and 16 shows its antenna. It is arranged that the antenna 16 receives radio signals sent from a radio transmitter 18 actuated by the operator who controls the submerged excavator from ashore.

Numerals

20 and 21 show hydraulic fluid pumps. respectively. driven by the prime mover l4, and 22 shows an auxiliary pump which serves to supply a pilot pressure for two three-valve assemblies. as will be described hereinafter. 23 indicates a universal joint coupler for prevention of undesirable twisting or flexture in the lead lines to the traction fluid motors; and 24 indicates an oil or fluid reservior.

Numeral 25 shows a 3-valve assembly composed of pilot-operated

directional control valves

25a, 25b and 250 juxtaposed to one another. in which the valve 250 is for a fluid line to the hydraulic motor 9, the valve 25b for that to the cylinder 11 for actuation of the arm, and the valve 250 is for that to the left-sided traction fluid motor 7. Another 3valve assembly is shown at 26 as composed of pilot-operated directional control valves 26a. 26b and 26c also arranged in juxtaposition. which valves being connected on respective lines to the rightsided traction fluid motor 8, the cylinder 12 for the bucket and the cylinder I0 for the boom.

Reference numerals 27 through 32 indicate solenoid valves for use in the operation of remote radio-control.

and each solenoid valve is specifically fabricated in a water-tight design or housed within a water-tight protective container. The solenoid valves 27 through 32 are in communication, via respective shuttle valves 33, with the corresponding directional control valves 25a through 25c in the assembly 25 and those 26a through 26c in the assembly 26, in that order mentioned.

In this arrangement, the solenoid valves 27 through 32 are adapted to be energized by electric signals sent from the radio receiver 17 through respective watertight cables 34 so that pilot pressure fluid from the auxiliary pump 22 be supplied to the directional control valves in the 3-

valve assemblies

25 and 26. Numerals 35 through 40 indicate manual flow control valves to be used by the operator riding on the excavator, and these manual flow control valves are in connection, through the respective shuttle alves 33, with the directional control valves 250 through 25c and 26a through 260 of the 3-

valve assemblies

25 and 26, in a corresponding manner.

It is also arranged that the manual flow control valves 35 through 40 serve to meter the flow of pilot pressure fluid from the auxiliary pump 22 to the directional control valves of the 3-

valve assemblies

25 and 26, in response to the angular displacement of their respective levers.

In another word, it is possible with this arrangement that the displacement of the valve spool to be attained in each directional control valve in the 3-valve assemblies varies depending on the degree of angular displacement effected in the operating lever of the associated manual flow control valve so that flow-metering effect is attainable to the hydraulic actuators hence controlling their working speeds in a desired manner.

The invention will now be described of its mode of operation again with reference to the drawings.

First, the mode of operation according to the invention will be described for the applied case in which the hydraulic excavator positioned at the bottom of sea or river is remote radio-controlled for the operation of raising or lowering its boom, for example, from land or aboard,

The radio transmitter 18 sends a triggering signal specified for the operation of raising the boom 4 to the radio receiver 17, which receiver 17 then responds to energize the solenoid valve associated with the boom cylinder so that the pilot pressure fluid from the auxiliary pump 22 is delivered to the respective shuttle valve 33.

As the pilot pressure fluid from the auxiliary pump 22 is then directed to the directional control valve 26c, the latter valve changes its position such that pressure fluid delivered from the hydraulic pump 21 is applied upon the working surface of the piston head in the boom cylinder 10. Thus, the piston rod in the boom cylinder 10 extends from the cylinder to raise the boom.

When it is desired to lower the boom 4, the similar step will be taken in that a different signal specified for lowering ofthe boom is sent to the receiver 17 from the transmitter 18; then the solenoid valve 32 is actuated to change its position so that the directional control valve 26c is supplied with the pilot pressure fluid from the auxiliary pump 22 through the associated shuttle valve 33; the valve 26c changes its position to direct the flow of pressure fluid from the pump 21 to the side of the piston rod in the boom cylinder 10; and thus the piston rod yields to lower the boom 4.

As apparent from the foregoing, it will be appreciated that by sending specified triggering signals through the radio transmitter and

receiver

18 and 17, the corresponding directional valves 250 through 25c and 26a through 26c are actuated to operate their respective hydraulic actuators such as the hydraulic motor 9, arm cylinder 11, traction motors 7 and 8, bucket cylinder 12, and boom cylinder 10, through cooperation of the associated solenoid valves 27 to 32 and shuttle valves 33, so that the remote radio-controlled operation of all the working elements including the boom 4, arm 5, etc can be accomplished in an efiicient manner.

Secondly, the mode of manual operation by the operator riding on the hydraulic excavator will be described by way of referring to actuating the boom.

Raising or lowering the boom 4 is attained through the function of the manual flow control valve 40. Namely, when the lever of the manual valve 40 is rotated, the directional control valve 260 is supplied increasingly with the pilot pressure fluid from the auxiliary pump 22 to change its position so that the pressure fluid from the hydraulic pump 21 is applied upon the piston head in the boom cylinder 10, thus extending the piston rod to raise the boom 4.

When actuating further the lever of the manual valve, the pilot-operated directional control valve changes its position, due to the function of the shuttle valve, such that the pressure fluid from the pump is directed to the side of the piston rod in the boom cylinder, thus the piston rod being yielded to lower the boom.

Therefore, the operator riding on the excavator can carry out the necessary operations in the same manner as in the ordinary shovel, by actuating the manual control valves 35 through 40.

Also, with this mode of operation by the operator riding on the machine, there is provided an advantage that by adjusting the rotating stroke of the lever in each manual flow control valve, the operator can control the flow rate of pressure fluid to the corresponding hydraulic actuator thereby attaining a desired rate of its working speed.

According to the amphibious hydraulic excavator of the invention, it is made possible to perform various works under water such as river or harbor excavating works including digging up the bottom of river or sea and loading the diggings onto the dump boat, in a remarkably easy manner, by virtue of the improved re' mote radio-controlled operation, Additionally, the invention also makes it possible, again thanks to its featured operation of remote radio-controlling, to perform such excavating operations at a working field on land with adverse environmental conditions such as an obstructed view, hazard in operation, presence of noxious gasses, unbearble heat, etc.

Since the hydraulic excavator of the invention can be operated either in a radio-controlled manner or in an ordinary manner by the operator riding on the machine, there will conveniently be provided free choice on the operating system well adapted for the working conditions, thus making contribution to significantly alleviating the physical fatigue of the operator as well as bettering the working conditions.

What is claimed is:

I. An amphibious hydraulic excavator comprising: an amphibious crawling truck; hydraulic motors for driving said crawling truck; a revolving platform mounted rotatably on said truck; a further hydraulic motor for rotating said revolving platform; a shovel assembly mounted on said revolving platform and composed of a boom, an arm and a bucket which are actuated by respective hydraulic cylinders; an engine room mounted on said revolving platform; a prime mover installed in said engine room; hydraulic pumps driven by said prime mover for delivering pressure fluid; pilot operated directional control valves for controlling the flows of pressure fluid to and from said hydraulic motors and said hydraulic cylinders, respectively; a snorkle means extending upwardly from the engine room for serving as an air suction and exhaust conduit for said prime movers; means for actuating said directional control valves, said actuating means being activated by radio signals and including a radio receiver for receiving triggering signals; a source of pilot pressure fluid; fluid lines connecting said source of pilot pressure fluid with the respective directional control valve; solenoid valves provided on the respective fluid line for actuation in re sponse to the triggering signals received by said receiver so as to control the flows of pilot pressure fluid to said directional control valves, respectively; shuttle valves positioned on the respective fluid lines downstream of said solenoid valves; by-pass fluid lines connecting between said source of pilot pressure fluid and the respective shuttle valves; and manual control valve means provided on the respective by-pass fluid lines for controlling the flows of pilot pressure fluid to said directional control valves, said manual control valve means being provided for adjusting the flow rate of pilot pressure fluid to said respective directional control valve; and wherein every part of said excavator is fabricated water-tight whereby said hydraulic excavator can be operated either in a remote radio-controlled manner or by normal manual operation.

Claims

1. An amphibious hydraulic excavator comprising: an amphibious crawling truck; hydraulic motors for driving said crawling truck; a revolving platform mounted rotatably on said truck; a further hydraulic motor for rotating said revolving platform; a shovel assembly mounted on said revolving platform and composed of a boom, an arm and a bucket which are actuated by respective hydraulic cylinders; an engine room mounted on said revolving platform; a prime mover installed in said engine room; hydraulic pumps driven by said prime mover for delivering pressure fluid; pilot operated directional control valves for controlling the flows of pressure fluid to and from said hydraulic motors and said hydraulic cylinders, respectively; a snorkle means extending upwardly from the engine room for serving as an air suction and exhaust conduit for said prime movers; means for actuating said directional control valves, said actuating means being activated by radio signals and including a radio receiver for receiving triggering signals; a source of pilot pressure fluid; fluid lines connecting said source of pilot pressure fluid with the respective directional control valve; solenoid valves provided on the respective fluid line for actuation in response to the triggering signals received by said receiver so as to control the flows of pilot pressure fluid to said directional control valves, respectively; shuttle Valves positioned on the respective fluid lines downstream of said solenoid valves; by-pass fluid lines connecting between said source of pilot pressure fluid and the respective shuttle valves; and manual control valve means provided on the respective by-pass fluid lines for controlling the flows of pilot pressure fluid to said directional control valves, said manual control valve means being provided for adjusting the flow rate of pilot pressure fluid to said respective directional control valve; and wherein every part of said excavator is fabricated water-tight whereby said hydraulic excavator can be operated either in a remote radio-controlled manner or by normal manual operation.