Extensible dipper stick for backhoe

Claim 2

A digging mechanism adapted for connection to a vehicle comprising a boom; a dipper stick pivotally connected to one end of said boom; a bucket pivotally connected to a free end of said dipper stick and a fluid ram having extensible and retractable elements respectively cooperating with said dipper stick and said bucket for pivoting said bucket on said dipper stick, the improvement of said dipper stick including an outer tubular member pivoted to said boom; an inner tubular member telescoped within said outer tubular member and having said bucket pivoted on the free end thereof; drive means for extending and retracting said inner member relative to said outer member; and support means for one of said elements, said support means encompassing said outer member and connected to said inner member whereby said support means moves with said inner member.

Claim 3

A digging mechanism as defined in claim 1, in which said support means comprises a sleeve encircling said outer tubular member, said sleeve having an opening corresponding in configuration to the peripheral surface of said outer member.

Claim 4

A digging mechanism as defined in claim 2, in which the connection to said inner member includes an arm extending beyond an end of said outer tubular member and in juxtaposed relation to said inner tubular member and means for interconnecting said arm and said inner tubular member.

Claim 5

A dipper stick having first and second telescoping members, one of said members adapted to be pivoted on one end of a boom and the other of said members having a bucket pivoted on the free end thereof; and fluid motor means having first and second elements for pivoting said bucket, the improvement of bracket means connected to said other of said members and having a support portion surrounding said one of said members, with one of said elements connected to said support portion, the other of said elements cooperating with said bucket whereby said support portion moves with said other of said members duriNg telescoping movement of said members.

Claim 6

A dipper stick having first and second telescoping members, one of said members adapted to be pivoted on one end of a boom and the other of said members having a bucket pivoted on the free end thereof; and fluid motor means having first and second elements for pivoting said bucket, the improvement of bracket means connected to said other of said members and having a support portion surrounding said one of said members, with one of said elements connected to said support portion, the other of said elements cooperating with said bucket whereby said support portion moves with said other of said members duriNg telescoping movement of said members.

Claim 7

A dipper stick as defined in claim 4, in which said members are polygonal in cross-sectional configuration; and said support portion has a corresponding cross-sectional configuration.

Claim 8

A dipper stick as defined in claim 5, in which said bracket means includes an arm extending from said support portion towards said bucket, said arm being connected to said other of said members adjacent said free end.

Claim 9

A dipper stick as defined in claim 4, in which said one of said members is an outer polygonal tubular member and said other of said members is an inner polygonal tubular member, and in which said dipper stick includes a cylinder and piston rod within said members and respectively having free ends connected to said outer and inner tubular members, the further improvement of said support portion comprising a corresponding polygonal ring surrounding said outer tubular member and said bracket means including first and second arms fixed to said ring and extending towards said bucket, said arms having free ends connected to said inner tubular member whereby extension and retraction of said piston rod will cause said ring to move with said inner tubular member.

Claim 10

A digging mechanism adapted for connection to a vehicle and comprising a boom; a dipper stick assembly including an outer, rectangular tubular member pivotally connected at one end to said boom, an inner, rectangular tubular member telescoped in said outer tubular member, and a first fluid ram within said tubular members and having opposite ends respectively connected to said outer and inner tubular members for extending and retracting said inner tubular member; a bucket pivotally supported on the outer end of said inner tubular member; bracket means including first and second arms located on opposite sides of said tubular members and having opposite ends, one end of said arms being connected to said inner tubular member adjacent said outer end, and a ring encompassing said outer tubular member and integral with said opposite ends of said arms; and a second fluid ram having one end supported on said ring and an opposite end operatively connected with said bucket for pivoting said bucket whereby said ring will support said second ram a predetermined distance from the pivot for said bucket and said support will move with said inner tubular member.

Claim 11

A digging mechanism adapted for connection to a vehicle and comprising a boom; a dipper stick assembly including an outer, rectangular tubular member pivotally connected at one end to said boom, an inner, rectangular tubular member telescoped in said outer tubular member, and a first fluid ram within said tubular members and having opposite ends respectively connected to said outer and inner tubular members for extending and retracting said inner tubular member; a bucket pivotally supported on the outer end of said inner tubular member; bracket means including first and second arms located on opposite sides of said tubular members and having opposite ends, one end of said arms being connected to said inner tubular member adjacent said outer end, and a ring encompassing said outer tubular member and integral with said opposite ends of said arms; and a second fluid ram having one end supported on said ring and an opposite end operatively connected with said bucket for pivoting said bucket whereby said ring will support said second ram a predetermined distance from the pivot for said bucket and said support will move with said inner tubular member.

Claim 12

A digging mechanism as defined in claim 8, including the further improvement of antifriction means on the opposite overlapping ends of said tubular members, said antifriction means respectively engaging a juxtaposed surface of the adjacent tubular member.

Claim 13

A digging mechanism as defined in claim 8, including the further improvement of linkage means pivoted on said opposite end of said second ram to said inner tubular member and said bucket at points spaced from the pivotal connection between said bucket and said inner tubular member; and in which said first fluid ram, said one end of said arms and said linkage means are connected to said inner member by a common connection.

Claim 14

A digging mechanism as defined in claim 8, further including a channel member extending from said ring and having a free end terminating adjacent said one end of said outer member when said members are in a retracted position; and hose receiving rings connected to said free end of said channel member.

Claim 15

A digging mechanism as defined in claim 8, further including a limit stop secured to said outer tubular member adjacent its opposite end, said limit stop being disposed in the path of movement of said ring during extension of said inner member and defining the maximum extended position for said inner member.

Claim 16

A digging mechanism as defined in claim 8, in which said arms have integral projections disposed in the path of movement of said operative connection between said bucket and said second fluid ram for limiting the extent of retraction of said second fluid ram.

Claim 17

A digging mechanism as defined in claim 8, including the further improvement of anti-friction means between said tubular members consisting of narrow elongated wear strips secured to the outer periphery of said inner tubular member at circumferentially spaced locations; and wear plates on the outer periphery of said outer tubular member engaging an inner surface of said ring.

Claim 18

A digging mechanism as defined in claim 8, in which said first fluid ram is between fully extended and retracted positions when said tubular members are in their fully extended and fully retracted positions and said second fluid ram is between fully extended and retracted positions when said bucket is in either of two extreme positions.

Claim 19

A digging mechanism as defined in claim 2, further including hose guide means integral with said sleeve and extending away from said free end of said inner tubular member.

Claim 20

A dipper stick as defined in claim 4, in which said bracket means includes a hose supporting means connected to said support portion, said hose supporting means extending away from said bucket having hose receiving rings on the free end thereof.