US3173561A

US3173561A - Boom construction for a mechanical excavator

Info

Publication number: US3173561A
Application number: US304585A
Authority: US
Inventors: Brocklebank Norman; Scott Gordon
Original assignee: Priestman Brothers Ltd
Current assignee: Priestman Brothers Ltd
Priority date: 1962-08-28
Filing date: 1963-08-26
Publication date: 1965-03-16
Anticipated expiration: 1982-03-16
Also published as: GB980137A

Description

March 1955 N. BROCKLEBANK ETAL 3,173,551

BOOM CONSTRUCTION FOR A MECHANICAL. EXCAVATOR Filed Aug. 26, 196-3 4 Sheets-$heet 1 Inventors /V Brock/elven G Scot f Attorneys March 1965 N. BROCKLEBANK ETAL 3,173,561

BOOM CONSTRUCTION FOR A MECHANICAL EXCAVATOR Filed Aug. 26, 1963 4 Sheets-Sheet 2 Invenlors /V, 5 rock/962M144 G. sco't March 15, 1955 N. BROCKLEBANK ETAL 3,173,551

BOOM CONSTRUCTION FOR A MECHANICAL EXCAVATOR Filed Aug. 26, 1963 4 Sheets-Sheet I5 Mamh 1965 N. BROCKLEBANK ETAL 3,173,561

BOOM CONSTRUCTION FOR A MECHANICAL. EXCAVATOR Filed Aug. 26, 1965 4 Sheets-Sheet 4 By kw Wrney 3 United States Patent 3,173,561 BOOM CONSTRUCTION FOR A MECHANICAL EXCAVATOR Norman Brocklebank, New Walk, Beverley, and Gordon Scott, Hull, England, assignors to Priestrnan Brothers Limited, Yorkshire, England, a British company Filed Aug. 26, 1963, Ser. No. 304,585 Claims priority, application Great Britain, Aug. 28, 1962, 33,005/ 62 Claims. (Cl. 214-138) This invention relates to hydraulically operated excavators, such as drag shovels and face showels, of the kind which have a boom and an arm pivoted together with a digging bucket mounted on the outer end of the arm. The boom and the arm are rocked relatively to each other and the bucket may be rocked on the outer end of the arm by means of hydraulic rams.

When a drag shovel of this kind is used for digging a trench, it is customary for the machine to stand in line with the trench and move backwards as it digs the trench towards itself. It is difiicult therefore to use a conventional drag shovel for excavating a trench which is very close to a wall or other construction because there is not room for the machine to align itself with the trench. Similar problems arise when using a conventional face shovel in a similar position.

According to the present invention the boom of such an excavator is in two pants which are detachably fixed together by a mounting which allows the outer part to slew from side to side relatively to the inner part and to be fixed to the inner part in any one of three different positions, in the first of which the two parts of the boom are aligned with each other so that the axis of the boom is straight as seen from above, and in the other two of which the outer part of the boom is set at an angle laterally as seen from above to the inner part of the boom, the outer part being offset in opposite directions in these two positions.

When the two parts of the boom are fixed together in the first position, that is to say with the whole boom straight, the evcavator can be used in the usual way. Thus if the excavator is a drag shovel it can be used in line with the trench which it is digging. However the arrangement enables the machine to dig a trench parallel and close to an obstruction such as a wall by slewing the superstructure of the machine in one sense on the chassis of the machine and slewing the outer upper part of the boom in the other sense relatively to the inner lower part of the boom and locking the two parts together in this relative position. When this is done the vertical plane containing the outer part of the boom is laterally offset from the central longitudinal line of the chassis so that a trench can be dug which is in line with the side edge of or even outside the wheel base of the chassis.

Preferably, the means for connecting the two parts of the boom to one another comprises a pivot pin which passes through tubular sockets in the two parts of the boom. The outer part of the boom can then swing relatively to the inner part about this pivot pin and can be fixed in any one of the three positions by bolts which pass through both parts of the boom. The boom pants are preferably steel plate box girder construction.

As well as being arranged to slew relatively to one another, the two parts of the boom may also be arranged telescopically as described in our co-pending application No. 304,586, filed August 26, 1962. In this case the two parts of the boom will be able to slew relatively to one another only when the boom is in its extended position.

One example of an excavator constructed in accordance 3,173,561 Patented Mar. 16, 1965 with the present invention is illustrated in the accompanying drawings, in which:

FIGURE I is a side elevation;

FIGURE 11 is a plan showing the excavator digging a trench in line with the right hand edge of its tracks;

FIGURE III is a side elevation of the boom per se with the outer part shown in one lateral position relative to the inner part;

FIGURE IV is a plan of the boom as shown in FIG- URE III;

FIGURE V is an enlarged plan of the connection between the two boom pants when they are aligned with one another;

FIGURE VI is a section taken on the lines VIVI in FIGURE IV;

FIGURE VII is a section taken on the line VII-VII in FIGURE IV; and,

FIGURE VIII is a section of the inner boom part only taken on the line VIII-VIII in FIGURE IV.

FIGURE IX is a section taken on the line IX-IX of FIGURE IV.

The excavator, which is the same machine as that illustrated and described in our copending applicatlon No. 304,586 filed August 26, 1962, consists of a superstructure 1 which is carried through a turntable 2 on a track laying chassis 3. An inner part 4 of a steel plated box shaped boom is pivoted at its lower end to a bracket 5 of the superstructure 1. The boom can be raised and lowered by means of a pair of hydraulic rams 6 which extend between lugs 7 on the superstructure 1 and lugs 8 at the outer end of the inner boom art 4. P The upper or outer part of the boom 9, which can telescope within the inner boom part 4, is arranged when extended to slew relatively to the inner part 4 and to be fixed in any one of three different positions relatively to the inner part 4. A digging arm 10 having a plate 11 at each side is pivoted by means of the brackets at 12 to the upper end of the boom part 9 to enable the digging arm 10 to swing backwards and forwards on the upper end of the boom. This swinging movement is controlled by a hydraulic ram 13 one end of which is anchored between lugs 14 on the inner end of the outer boom part 9 and the other end of which is anchored to a bracket 15 carried between the plates 11. A digging bucket 16 is pivotally mounted on the outer end of the arm 10 and can be rocked backwards and forwards on the end of the arm by a hydraulic ram 17. One end of the ram 17 is anchored to the plates 11 and the other end is connected to flanges 18 on the back of the bucket through a swivel link 19. The bucket has two alternative connections 20 and 21 by either of which it can be connected to the end of the arm 10. The arrangement is such that the bucket can be disconnected from the end of the arm 10, swung around through on the swivel 19 and reconnected by the other connection 20 or 21 to the arm 10. In this way the excavator can be converted from a drag shovel or back-actor to a face shovel and vice versa easily. This arrangement is fully described and claimed in our copending application No 294,658 filed July 12, 1963.

The construction of the two boom parts 4 and 9 which enables the outer part 9 to slew relatively to the inner part and to telescope into the inner part is shown most clearly in FIGURES III to VIII. The inner boom part 4 consists of two box sections 22 arranged side by side and connected by .a bottom plate 23 which is welded to them. The two box sections increase in depth from a minimum at the inner end to a maximum a short dis tance away from the outer end. The inner boom part is therefore substantially U-shaped in section and the outer and beneath inturned lips 23a on the inner walls of thebox sections. These inner walls of the box sections 22 extend above the sections asthey taper. in a direction towards the inner end of the boom to provide a channel of constant height to receive the inner end of the outer boom parts as it telescopes within the inner part. At their extreme inner ends, the boxisections 22 terminate in tubular sockets 24 for receiving the pivot pin which connects the inner end of the boom to the bracket 5.

At its extreme outer end, the boom part 4 is strengthened with upper .and

lower plates

25 and 26 respectively which define between them an enlarged housing 27 which enables the extreme inner end of the outer part 9 to move from side to side when the outer boom part 9 is slewed relatively to the inner part 4. The bottom plate 26 extends across the run width of the boom 'but the upper plate has its centre and rear portion cut away to provide access to the housing 27. The lugs 8 for the rams 6 are welded to the top plate 25..

The outer boom part 9 is also of boxconstruction and.

consists of four plates welded together at each corner of the section. There is .a portion 28 of constant height at the inner end of the boom part 9 but beyond this the rest of the boom part tapers towards its outer end. At its extreme outer end the part '9 is formed with a tubular socket 29 for receiving a pivot pin which connects the plate brackets 11 to theen'd of the boom.

Adjacent its inner end the outer boom part9 is formed with a tubular socket 30 and adjacent its outer end it is formed with another tubular socket 31 of similar shape and size to the first. The socket 31 'is supported by a Web 32 where it'projects above the tapering boxsection of the boom part 9' so that it has the same height as the socket 30. When the boom is in its fully extended. position as shown in FIGURES III and IV, a pivot pin; 33 extends down through the socket' 30 and through aligned tubular sockets 34 and 35 in the upper plate 25 and in the lower plates 23'and 26 vrespectively to connect the two boom parts together. The outer boom part 9 is free to slew about the pivot pin 33 but it can 'be bolted in any one of three positions in which it extends straight forwards in alignment with the inner boom part '4 as shown in FIGURE V or at anangle of 25 to one end of the outer part 9 is also secured by means of the

bolts

36, 37 and 38 which now pass through ,holes'. 5 2,

53 and 54 respectively in the plate 23 and in a strengthening plate 55 immediately beneath the plate 23 .at the inner' end of the boom part 4. The outer boom part 9 cannot of course slew from side t'o's ide relatively to the innerpart 4 when'it is retracted in this way. This retraction of the boom is-fullydescribed and claimed .in our cop'ending application No. 304,586, filed August 26, 1962.

The construction of the boom and the mounting of the bucket 16 on the end of the arm 10 enable the excavator 'to be very adaptable and to be used for a wide variety of ,functions: If the bucket is mounted as shown in FIGURES I and II, the machine is ready for use as a back-actor or drag shovel. If the two boom parts are locked in the straight ahead positions as illustrated in FIGURE V, a trench can be dug in line with the central longitudinal lineof the chassis. the super-structu-re'l is slewed to one side or the other through 25, for example clockwise as seen from above and as shown in FIGURE II, and the outer boom part 9 is slewed in an anti-clockwise direction relatively to venient to retractthe outer boom part 9 within the inner part 4 to reduce the lengthof the boom. With the boom retracted in this way, the excavator is also ready for transporting a We'clairn: v I t I 1. In an excavator of the kind having a chassis, asu- J perstructure, turntable meansrotatably mounting said fixed in the straight ahead position shown in FIGURE 7 V by means of three

bolts

36, 37 and, 38 which pass through sockets in the inner end of the outer boom part 9 and through holes 39, 40 and '41 respectively formed in the

bottom plates

23 and 26 of the inner boom part 4. When the outer boom part 9 is slewed to, the left, as seen from above and in the direction in which the boom points, the

bolts

37 and 38 are transferred to holes 42 and 43 in the

bottom plates

23 and 26 and the bolts 36 are replaced by a pair of bolts 44 and 45 which pass through tubular sockets 46 at the extreme inner 'end of the outer boom part 9 and through sockets -47 and 48 respectively in one side wall of the housing 27. Similarly, when the outer boom part is slewed in the other direction the

bolts

37 and 38 are transferred to holes 42 and 49 'in the base plates23 and 26 and the bolts' superstructure on said chassis for'slewing movements relative thereto, a boom, means pivot-ally mounting ,said boomon-said superstructure, a digging arm, means pivotally mounting said digging arm on said boonnand a digging bucket mounted on said digging arm; the improved arm' rocking means and boom which comprises an inner boom part mounted on said superstructure, an outer boom part carrying said digging arm, a hydraulic ram connected between said outer boom part and digging arm to rock said arm on said boom, means connecting a said inner and outer boom parts together whereby. said said outer boom parts are aligned with each otherso that the. axis of said boom is straight as seen from above,

44 and 45 pass through the sockets 46 anduthrough sockets 50 and 51 respectively in the other side wall ofend -from.the bottom plates .or side walls of the housing 7 27 and removing the pivot pin 33. The outer boom part 9 is then retracted through the housing 27 until the socket 31 is aligned with the sockets 34 and 35. It is.

then secured in position by reinse'rting the pivot pin33 27 and through the 599149; 31 in thepart 9. The inner through the tubular sockets 34 and 35 in the housing said second position being defined when said outer boom part is set at an angle to one side as seen from above to said inner boom part,'saicl third position being defined when said outer boom part is set at an angle to the other side as seen from above to said inner boom part; and means forffixing said outer boom part in any one of said three positions. V

2. An excavator according to claim 1, in which said means for pivotally connecting said boom parts together comprises tubular sockets in said inner and outer boom parts and a pivot pin passing through said tubular sockets.

3. An excavator according to claim 2, in which said means for fixing said outer boompart in each of said three positions comprises holes in both of said boom parts, at least one hole in each boom part being positioned to register with at least one hole in the other boom part when said outer boom occupies each of its said three positions, and bolt means passing through said registering holes. I v 3 t 4, An "excavator according to claim 1, in which the inner boom-partcomprises two closed box sections ar- However, if

ranged side by side, a bottom plate extending between two said box sections, a top plate extending between said two box sections at the outer end thereof to define a housing adapted to receive the inner end of said outer boom part, said means for fixing said outer boom part in each of its three positions being provided within said housing.

5. In an excavator of the kind having a chassis, a superstructure, turntable means rotatably mounting said superstructure on said chassis for slewing movements relative thereto, a boom, means pivotally mounting said boom on said superstructure, a digging arm, means pivotally mounting said digging arm on said boom, and a digging bucket mounted on said digging arm; the improved arm rocking means and boom which comprises an inner boom part mounted on said superstructure, an outer boom part carrying said digging arm, a hydraulic rain connected between said outer boom part and said digging arm to rock said arm on said boom, and means for fixing said inner and outer boom parts to each other in any one of three positions; said positions including a first position defined when said inner and said outer boom parts are aligned with each other so that the axis of said boom is straight as seen from above, a second position defined when said outer boom part is set at an angle to one side as seen from above to said inner boom part, and a third position defined when said outer boom part is set at an angle to the other side as seen from above to said inner boom part.

References Cited by the Examiner UNITED STATES PATENTS 3,027,026 3/62 Conquet 2l4l38 FOREIGN PATENTS 556,535 2/57 Italy.

HUGO O. SCHULZ, Primary Examiner.

Claims

1. IN AN EXCAVATOR OF THE KIND HAVING A CHASSIS, A SUPERSTRUCTURE, TURNTABLE MEANS ROTATABLY MOUNTING SAID SUPERSTRUCTURE ON SAID CHASSIS FOR SLEWING MOVEMENTS RELATIVE THERETO, A BOOM, MEANS PIVOTALLY MOUNTING SAID BOOM ON SAID SUPERSTRUCTURE, A DIGGING ARM, MEANS PIVOTALLY MOUNTING SAID DIGGING ARM ON SAID BOOM, AND A DIGGING BUCKET MOUNTED ON SAID DIGGING ARM; THE IMPROVED ARM ROCKING MEANS AND BOOM WHICH COMPRISES AN INNER BOOM PART MOUNTED ON SAID SUPERSTRUCTURE, AN OUTER BOOM CARRYING SAID DIGGING ARM, A HYDRAULIC RAM CONNECTED BETWEEN SAID OUTER BOOM PART AND DIGGING ARM TO ROCK SAID ARM ON SAID BOOM, MEANS CONNECTIN G SAID INNER AND OUTER BOOM PARTS TOGETHER WHEREBY SAID OUTER BOOM PART IS ADAPTED TO SLEW FROM SIDE TO SIDE RELATIVELY TO SAID INNER BOOM PART BETWEEN THREE POSITIONS; SAID FIRST POSITION BEING DEFINED WHEN SAID INNER AND SAID OUTER BOOM PARTS ARE ALIGNED WITH EACH OTHER SO THAT THE AXIS OF SAID BOOM IS STRAIGHT AS SEEN FROM ABOVE, SAID SECOND POSITION BEIND DEFINED WHEN SAID OUTER BOOM PART IS SET AT AN ANGLE TO ONE SIDE AS SEEN FROM ABOVE TO SAID INNER BOOM PART, SAID THIRD POSITION BEIND DEFINED WHEN SAID OUTER BOOM PART IS SET AT AN ANGLE TO THE OTHER SIDE AS SEEN FROM ABOVE TO SAID INNER BOOM PART; AND MEANS FOR FIXING SAID OUTER BOOM PART IN ANY ONE OF SAID THREE POSITIONS.