US3219214A

US3219214A - Excavator dipper door mounting

Info

Publication number: US3219214A
Application number: US191794A
Authority: US
Inventors: Baer Josef
Original assignee: Bucyrus Erie Co
Current assignee: Caterpillar Global Mining LLC
Priority date: 1962-05-02
Filing date: 1962-05-02
Publication date: 1965-11-23
Anticipated expiration: 1982-11-23
Also published as: GB982491A

Description

' Nov. 23, 1965 J. BAER EXCAVATOR DIPPER noon MOUNTING 3 Sheets-Sheet 1 Filed May 2, 1962 m m m m JOSEF BAER BY @972.

/M ATTORNEY NOV. 23, 1965 J, BAER 3,219,214

EXCAVATOR DIPPER DOOR MOUNTING Filed May 2, 1962 S Sheets-Sheet 2 FIG. 4

INVENTOR.

JOSEF BAER Nov. 23, 1965 J, BAER 3,219,214

EXCAVATOR DIPPER DOOR MOUNTING Filed May 2. 1962 3 Sheets-Sheet 3 INVENTOR:

JOSEF BAER I BY M574;

ATTORNEY United States Patent OfiFice 3,219,214 Patented Nov. 23, 1965 3,219,214 EXCAVATOR DIPPER DOOR MGUNTING Josef Baer, outl1 Milwaukee, Wis., assignor to Bucyrus- Erie Company, South Milwaukee, Wis., a corporation of Delaware Filed May 2, 1962, Ser. No. 191,794 6 Claims. (Cl. 214-145) This invention relates to the mounting of an excavator dipper door upon supporting hinge bars and more particularly to the pin connection which joins the dipper door to the hinge bars.

In excavator clippers, a dipper door is swingably attached thereto to open and close at the bottom thereof to discharge or contain materials excavated by the dipper as the use may be. The door is supported by laterallyspaced hinge bars pivotally secured to the rear portion of the dipper. A connection, either permanent or demountable, secures the dipper door to the hinge bars.

It has been a usual practice to form the dipper door and hinge bars as an integral unit by means of casting or by fabricating them as a weldment. During digging operations, the dipper door is subjected to high impact loads from rocks or like objects. The integral unit is a rigid structure and, as such, is unable to absorb impact loads of great magnitude and consequently damage frequently results, particularly at the juncture of the door and the hinge bars.

It has also been a practice to provide a demountable connection between the dipper door and the hinge bars in an attempt to overcome the inherent deficiencies of an integral unit. Many of the demountable connections require a number of accurately machined parts; others are unable to absorb impact loads and become loosened during operation of the dipper which results in damage to the hinge bars and a consequent loss in operating time required to repair and maintain these connections.

Accordingly, an object of this invention is to provide demountable pin connections between a dipper door and the supporting hinge bars wherein a shock absorbing resilient material is disposed between the components of the pin connections. Such construction allows impact loads to be absorbed within the connection and prevents the damage occasioned by the previously described rigid structures.

Another object of this invention is to provide a means for securing a dipper door to a hinge bar wherein a minimum number of machined parts are required.

Another object of this invention is to provide a pin connection between a dipper door and a hinge bar wherein the connection has cooperating tapered members adapted for movement relative to each other to tighten the connection, in which one of the members holds a resilient material, and is formed in such a manner that the resilient material is retained in the connection.

Another object of this invention is to provide an improved tapered resilient means for maintaining a pin connection in a dipper door when said door is subjected to impact loadings.

This invention consists of the novel parts and of the combination and arrangement thereof which are disclosed and described in the following specification and drawings of which:

FIGURE 1 is a side elevation view of an excavator dipper having a door mounted on a pair of laterallyspaced hinge bars, only one of which is shown;

FIGURE 2 is a cross-sectional view of the pin connection joining the door and a hinge bar taken at 22 of FIGURE 1;

4 FIGURE 3 is a similar cross-section-al view of a second embodiment of the pin connection;

FIGURE 4 is a similar cross-sectional view of a third embodiment of the pin connection;

FIGURE 5 is an end view of a fourth embodiment of the pin connection; and

FIGURE 6 is a cross-sectional view of the pin connection of FIGURE 5 taken at line 66 of FIGURE 5.

In FIGURE 1 an excavator dipper 20 is provided with a swingable door 21 adapted to close the bottom of the dipper. The door 21 is mounted to swing relative to the dipper 20 by means of a pair of laterally-spaced hinge bars 22 being pivotally connected to the dipper as at 24. A latch means 23 is provided at the front of the dipper 20 to hold the door 21 in a closed position.

Referring now to FIGURE 2, the door is supported on a surface 25 on the upper side of each hinge bar 22 along an axis of support normal to supporting surface 25. With multiple axes of support the support is along the resultant of the multiple axes. In actual practice the door supporting surface usually extends along the full length of that portion of the hinge bar adjacent the underside of the dipper door.

In a demountable connection between a dipper door and a hinge bar, it is desirable to maintain the door supporting surface 25 of the hinge bar in supporting relationship to the underside of the door and at the same time provide a resilient means between the door and the pin 29. In FIGURE 2, a pair of laterally-spaced

mounting lugs

26 and 27 depend from the underside of the dipper door 21. The lugs are spaced a sufficient distance to accommodate the width of the hinge bar 22.

Each of the

lugs

26 and 27 are provided with a suitable transverse opening 28 to receive a retaining pin 29 having a head 30, a central body 31 and a threaded shank 32. The transverse opening in each

mounting lug

26 and 27 is dimensioned to accommodate the corresponding end of the retaining pin 29, and the transverse openings 28 and the retaining pin 29 is rectangular. Both the head and threaded shank have a

lower surface

33 and 34 respectively which is furthest from the door and shaped to conform to the

surfaces

35 and 36, respectively, in the opening 28 in each of the mounting lugs. The relative dimensions of the retaining pin and the transverse openings in the mounting lugs are proportioned to permit' movement of the pin 29 along its longitudinal axis. The pin is locked by tightening threaded nut 37 against washer 38.

A transverse opening 45 is provided in each hinge bar 22 to permit the insertion of the central body 31 of the retaining pin 29 and to receive a metal Wedge member 40 which carries a block of resilient material 41, such as rubber of the like. The wedge member 40 is adapted to abut the head 30 of the retaining pin 29 for adjustable axial movement and wedging action upon tightening of the nut 37. The wedge member 40 may be a small casting or metal stamping having but one machined surface 42. The interior of the wedge member is adapted to receive the block of resilient material 41 and substantially enclose the block upon all sides except one thereby eliminating the need for bonding the resilient block 41 to the metal wedge member 40.

Each hinge bar 22 is provided with transverse opening having a tapered surface 43 adapted to wedge against the surface 42 of the wedge member 40. Accordingly, axial movement of the pin 29 to the right, as shown in the drawings, will force the hinge bar 22 into contact with the bottom of the dipper door 21 and compress the resilient block 41 through the wedging action of the tapered surface 43 against wedge member 40. The tightening of nut 37 compresses the resilient block 41 to provide a force to maintain the hinge bar 22 in contact with the door 21 thereby locking the pin connection during operation of the dipper and the door.

Coaction of the parts of the present invention permit the resilient material to absorb shocks from impact loads acting on the door, and, at the same time, take-up of the locking means, as by tightening nut 37, prevents loosening of the pin connection and biases said block 41.

As shown in FIGURE 2, both the resilient block 41 and the cooperating

tapered surfaces

42 and 43 are disposed in series between that surface 25 of the hinge bar in contact with the door 21 and

surfaces

33 and 34 which support the retaining pin 29 in the transverse openings 28 of the

mounting lugs

26 and 27. Accordingly, any compression of the resilient block member 41 resulting from impact loads transmitted by the door and the hinge bar will cause the components of the pin connection to be pressed together with added force.

The pin connection of the present invention also uses a minimum number of machined component parts. Only the cooperating

tapered surfaces

42 and 43 of the hinge bar and wedge members need be machined to provide a smooth surface for facilitating longitudinal adjustment of the pin to effect compression of the resilient block 41. Such adjustment will bias the hinge bar against the bottom surface of the door and maintain it by locking the pin connection, as by tightening nut 37.

In FIGURE 3 the door 21 is provided with

mounting lugs

26 and 27 depending from the underside thereof. Each of the

lugs

26 and 27 are provided with a suitable transverse opening 28 to receive retaining pin 29. Said pin comprises a head 30, a central body 31, and a threaded shank 32. The transverse opening 28 in each

mounting lug

26 and 27 is similar to that described in conjunction with FIGURE 2 and is dimensioned to accommodate the respective ends of the retaining pin 29.

The pin connection of FIGURE 3 is a subspecies of FIGURE 2 and differs from that disclosed in FIGURE 2 in that the transverse opening 50 in hinge bar 22 is sub stantially parallel to surface 25, and allows a sufficient opening for the insertion of a wedge 51 having a tapered surface 52 for engaging surface 42 of wedge member 40 which carries a block of resilient material 41. The transverse opening 50, having parallel surfaces is simpler to machine in the hinge bar 22 than the opening 45 of FIG- URE 2 which has a tapered surface 43.

Axial movement of the pin 29 to the right, as shown, by tightening nut 37 forces the hinge bar 22 into contact with the bottom of the dipper door 21 and compresses the resilient block 41 between wedge member 51 and pin 29.

Any compression of the resilient member 41 resulting from impact loads transmitted by the door and the hinge bar will cause the components of the pin connection to be pressed together with added force rather than causing a separation of those components.

Referring now to FIGURE 4, a third embodiment of the invention is shown wherein the depending

lugs

26 and 27 are provided with

transverse openings

61 and 62. Transverse opening 62 is preferably tapered to receive tapered surface 63 of pin 60. Located between

lugs

26 and 27 is hinge bars 22 provided with tapered transverse opening 64. The tapered surface of opening 64 is engaged by and wedged against tapered surface 63 of pin 60. Resilient mounting blocks 64 and 65 are located in

transverse openings

61 and 62 respectively with

resilient blocks

66 and 67 in engagement with

transverse openings

61 and 62 and the mounting blocks 64 and 65 in engagement with pin 60.

As nut 37 is tightened to move pin 60 axially toward washer 38, tapered surfaces 63 and Marc in engagement and

resilient blocks

66 and 67 are compressed against the

transverse openings

61 and 62 respectively, thereby resulting in the urging of hinge bar 22 against door 21. With the pin connection locked as by nut 37, impact loads striking the dipper and dipper door 21 do not loosen or otherwise impair the connection between the hinge bars and the dipper door.

In FIGURES 5 and 6 a fourth embodiment of the invention is shown. Specifically, depending

lugs

26 and 27 are provided with transverse openings 80. The openings have convergent tapered surfaces 81 for receiving pin 89 therethrough. The pin 89 comprises an enlarged central portion 82, two intermediate portions 83 having tapered surfaces which diverge toward central portion 82, and threaded end portions 84.

Hinge bar 22 is provided with a cylindrical opening 85 to receive the central portion 82 of pin 89. It should be noted that in the embodiment of FIGURES 5 and 6 there is no contact between the door 21 and the hinge bar 22.

To provide an impact absorbing means between the

lugs

26 and 27 and the hinge bar 22, tubular resilient members 86 are inserted in the openings between tapered openings and the tapered intermediate portions 83 of pin 89. The resilient members 86 are forced inwardly toward the hinge bar by the threading of nuts 87 against collars 88 to compress the resilient members between openings 80 and pin 89. In this manner the door is connected to the hinge bars so that impacts on the dipper or door do not act directly on pin 89, but rather are cushioned through resilient members 86. As a result, such impacts do not loosen the pin connection and the door is thereby secured to the hinge bars 22.

Thus various pin connections for a dipper door of an excavator have been described, and the construction of the pin connections is such that a resilient means is wedged or compressed to maintain the connection between the dipper door and the hinge bars wherein impacts do not occasion a loosening of the pin connection.

Having described and illustrated four embodiments of the invention, it is to be understood that this invention is not to be limited to the specific form or arrangement of parts herein described and shown, or specifically covered by the claims.

What is claimed is:

1. In a dipper door mounting the combination comprising:

a dipper door;

a hinge bar extending beneath the door;

a pair of mounting lugs attached to and depending from said door with one on each side of said hinge bar;

a pin extending through said lugs and said hinge bar with a tightening nut thereon;

a resilient member interposed between said pin and one of said members through which the pin extends, such resilient member being substantially enclosed on both axial and transverse sides with respect to said pin for constricted compression thereof in both said axial and transverse directions; and

Wedge means associated with said pin that compresses said resilient member between said axial and transverse enclosed sides upon bringing up said tightening nut.

2. A mounting as in claim 1, wherein said resilient member is disposed between said pin and said hinge bar,

said pin has a face that acts longitudinally upon said resilient member upon bringing up said tightening nut, and

said wedge means is interposed between the resilient member and said hinge bar to compress the resilient member upon longitudinal movement of the pin in response to bringing up said tightening nut.

3. A mounting as in claim 1 wherein said resilient member is disposed between said pin and a mounting lug, and

said wedge means is between the pin and hinge bar to urge the pin transversely against the resilient member upon bringing up the tightening nut.

4. A mounting as in claim 1 wherein said pin forms an annular space between itself and a lug through which it extends,

said resilient member is disposed in said annular space,

said wedge means comprises a tapered wall of said annular space, and

said tightening nut includes a collar bearing axially against said resilient member,

said collar being movable against the resilient member upon bringing up said tightening nut to thereby compress said resilient member .between the pin, lug and collar.

5. In a dipper door mounting the combination comprising:

a dipper door;

a hinge bar extending along side the door;

a pair of lugs on said door, one on each side of said hinge bar;

an axially movable pin joining said hinge bar and said lugs;

a cup shaped member having a wedge portion;

a resilient block within said cup shaped member, said block and cup shaped member being disposed between said pin and one of said members which it 101118;

wedge means acting upon said cup shaped member to compress said resilient block within said cup shaped member upon axial movement of said pin; and

tightening means on said pin to draw the pin axially against the action of said wedge means.

6. In a dipper door mounting the combination comprising:

a dipper door;

a hinge bar extending beneath the door;

a pair of mounting lugs attached to said door with one on each side of said hinge bar;

a pin in said hinge bar extending through openings in said lugs with spaces between the pin and each lug;

a resilient member in each of said spaces interposed between the pin and the associated lug;

an axially displaceable collar on each end of said pin facing axially inward and bearing against said resilient members; and

tightening means on said pin which move said collars against said resilient members and compress the same between said pin and lugs.

References Cited by the Examiner UNITED STATES PATENTS 1,735,716 11/1929 Anderson 214 1,883,915 10/1932 Holcomb 214145 1,981,267 11/1934 Heffelfinger 214145 2,180,348 11/1939 Daniels 214145 2,335,352 11/1943 Murtaugh 214146 2,561,518 7/1951 Larsen 214145 2,788,907 4/ 1957 Larsen 214145 3,034,820 5/ 1962 Schwartz et al. 214147 HUGO O. SCHULZ, Primary Examiner.

Claims

1. IN A DIPPER DOOR MOUNTING THE COMBINATION COMPRISING: A DIPPER DOOR; A HINGE BAR EXTENDING BENEATH THE DOOR; A PAIR OF MOUNTING LUGS ATTACHED TO AND DEPENDING FROM SAID DOOR WITH ONE ON EACH SIDE OF SAID HINGE BAR; A PIN EXTENDING THROUGH SAID LUGS AND SAID HINGE BAR WITH A TIGHTENING NUT THEREON; A RESILIENT MEMBER INTERPOSED BETWEEN SAID PIN AND ONE OF SAID MEMBERS THROUGH WHICH THE PIN EXTENDS, SUCH RESILIENT MEMBER BEING SUBSTANTIALLY ENCLOSED ON BOTH AXIAL AND TRANSVERSE SIDES WITH RESPECT TO SAID PIN FOR CONSTRICTED COMPRESSION THEREOF IN BOTH SAID AXIAL AND TRANSVERSE DIRECTIONS; AND WEDGE MEANS ASSOCIATED WITH SAID PIN THAT COMPRESSED SAID RESILIENT MEMBER BETWEEN SAID AXIAL AND TRANSVERSE ENCLOSED SIDES UPON BRINGING UP SAID TIGHTENING NUT.